WorldWideScience

Sample records for biologically harmful radiation

  1. Evaluation of DNA dosimetry to assess ozone-mediated variability of biologically harmful radiation in Antarctica

    NARCIS (Netherlands)

    George, AL; Peat, HJ; Buma, AGJ

    In this study we investigated the use of a DNA dosimeter to accurately measure changes in ultraviolet B radiation (UVBR; 280-315 nm) under Antarctic ozone hole conditions. Naked DNA solution in quartz tubes was exposed to ambient solar radiation at Rothera Research Station, Antarctica, between

  2. Radiation biology

    International Nuclear Information System (INIS)

    Neumeister, K.

    1977-01-01

    This chapter is included in a textbook which is primarily intended for medical students. The following topics are dealt with: radiation effects on molecules; chemical and biochemical radiation effects; modification of radiation effects and radiosensitivity; radiation-induced pathomorphological and pathophysiological effects in organs and organ systems; radiation syndrome; radiation effects in embryos and fetuses; genetic radiation effects; carcinogenesis and leukemogenesis after irradiation; and radiation effects after intake of radionuclides

  3. Biological Effects of Radiation

    International Nuclear Information System (INIS)

    Jatau, B.D.; Garba, N.N.; Yusuf, A.M.; Yamusa, Y. A.; Musa, Y.

    2013-01-01

    In earlier studies, researchers aimed a single particle at the nucleus of the cell where DNA is located. Eighty percent of the cells shot through the nucleus survived. This contradicts the belief that if radiation slams through the nucleus, the cell will die. But the bad news is that the surviving cells contained mutations. Cells have a great capacity to repair DNA, but they cannot do it perfectly. The damage left behind in these studies from a single particle of alpha radiation doubled the damage that is already there. This proved, beyond a shadow of doubt, those there biological effects occur as a result of exposure to radiation, Radiation is harmful to living tissue because of its ionizing power in matter. This ionization can damage living cells directly, by breaking the chemical bonds of important biological molecules (particularly DNA), or indirectly, by creating chemical radicals from water molecules in the cells, which can then attack the biological molecules chemically. At some extent these molecules are repaired by natural biological processes, however, the effectiveness of this repair depends on the extent of the damage. The interaction of ionizing with the human body, arising either from external sources outside the body or from internal contamination of the body by radioactive materials, leads to the biological effects which may later show up as a clinical symptoms. Basically, this formed the baseline of this research to serve as a yardstick for creating awareness about radiation and its resulting effects.

  4. Radiation sterilization of harmful algae in water

    International Nuclear Information System (INIS)

    Byung Chull An; Jae-Sung Kim; Seung Sik Lee; Shyamkumar Barampuram; Eun Mi Lee; Byung Yeoup Chung

    2007-01-01

    Complete text of publication follows. Objective: Drinking water, water used in food production and for irrigation, water for fish farming, waste water, surface water, and recreational water have been recently recognized as a vector for the transmission of harmful micro-organisms. The human and animal harmful algae is a waterborne risk to public health and economy because the algae are ubiquitous and persistent in water and wastewater, not completely removed by physical-chemical treatment processes, and relatively resistant to chemical disinfection. Gamma and electron beam radiation technology is of growing in the water industry since it was demonstrated that gamma and electron beam radiation is very effective against harmful algae. Materials and Methods: Harmful algae (Scenedesmus quadricauda(Turpin) Brebisson 1835 (AG10003), Chlorella vulgaris Beijerinck 1896 (AG30007) and Chlamydomonas sp. (AG10061)) were distributed from Korean collection for type cultures (KCTC). Strains were cultured aerobically in Allen's medium at 25□ and 300 umol/m2s for 1 week using bioreactor. We investigated the disinfection efficiency of harmful algae irradiated with gamma (0.05 to 10 kGy for 30 min) and electron beam (1 to 19 kGy for 5 sec) rays. Results and Conclusion: We investigated the disinfection efficiency of harmful algae irradiated with gamma and electron beam rays of 50 to 19000 Gy. We established the optimum sterilization condition which use the gamma and electron beam radiation. Gamma ray disinfected harmful algae at 400 Gy for 30 min. Also, electron beam disinfected at 1000 Gy for 5 sec. This alternative disinfection practice had powerful disinfection efficiency. Hence, the multi-barrier approach for drinking water treatment in which a combination of various disinfectants and filtration technologies are applied for removal and inactivation of different microbial pathogens will guarantee a lower risk of microbial contamination.

  5. Protective role of plants against harmful radiation

    International Nuclear Information System (INIS)

    Gautam, Shreesh Kumar; Kumar, Pawan; Singh, Abhishek; Kumar, Vikas; Bharti, Navaldey

    2012-01-01

    The rapid technological advancement has increased human exposure to ionizing radiations enormously. Ionizing radiations produces deleterious effects in the living organisms. Widespread use of radiation in diagnosis therapy, industry, energy sector and inadvertent exposure during air and space travel, nuclear accidents and nuclear terror attacks requires safeguard against human exposures. Lead shielding and other physical measures can be used in such situations but with difficulty to manage; thus pharmacological intervention could be the most prudent strategy to protect humans against the harmful effect of ionizing radiations. These pharmacological agents are radioprotectives; The development of radioprotective agents has been the subject of intense research in view of their potential for use within a radiation environment. However, no ideal, safe synthetic radio protectors are available to date, so the search for alternative sources including plants has been ongoing. In Ayurveda, the traditional Indian system of medicine, several plants have been used to treat free radical-mediated ailments and, therefore, it is logical to expect that such plants may also render some protection against radiation damage. This all is due to antioxidant enzymes, nitroxides, and melatonin, antiemetic, anti-inflammatory. haemopoitic and immunostimulant compounds. Some of the plants which are found to be radioprotective are Centella asiatica, Ginkgo biloba, Hippophae rhamnoides, Ocimum sanctum, Podophyllurn hexandrum, Tinospora cordifolia, Emblica officinalis, Phyllanthus amarus, etc. So there is an urgent need to identify and characterize the many of the plants in relation to the radioprotection. Besides these medicinal plants there are also some fruits and vegetables which are having good response against harmful radiations such as Kiwifruit Actinidia deliciosa (Actinidaceae), Cape Gooseberry Physalis peruviana (Solanaceae). They protect against the radiation-induced damage by

  6. [Harmful biological agents at museum workposts].

    Science.gov (United States)

    Skóra, Justyna; Zduniak, Katarzyna; Gutarowska, Beata; Rembisz, Daria

    2012-01-01

    The aim of the studies was to determine the level and kind of microbiological contamination of air and surfaces in museum premises with various collection specificities. In addition, the criteria for selecting indicators of contamination with harmful biological agents at museum workposts are proposed. The analysis of microbial contamination was carried out in 14 museum premises (storehouses, restoration workshops, exhibition hall). Microbiological air purity was measured with a MAS-100 Eco Air Sampler. Surface samples were collected using contact plates RODAC Envirocheck. Biochemical API tests were used to identify bacteria and yeasts. Fungi were diagnosed with taxonomic keys, based on macro- and microscopic mycelia assessment. The levels of microbiological contamination in museums varied and ranged from 2.1 x 10(2) to 7.0 x 10(3) cfu/m3 in the air and from 1.4 x 10(2) to 1.7 x 10(4) cfu/100 cm2 on surfaces. The dominant microorganisms were fungi, which accounted respectively for 18-98% and 23-100% of all isolates from tested sites and surfaces. It was found that the amount of fungi in the indoor air of the Museum of Archeology and Ethnography and the Museum of Independence Traditions equaled respectively 4.2 x 10(2) cfu/m3 and 1.4 x 10(4) cfu/m3, which means that they exceeded the recommended reference value of 2.0 x 10(2) cfu/m3. Having analyzed the frequency of strain isolation, the source of microorganisms and the hazard to human health, 10 fungal species were isolated, which may be regarded as indicators of contamination with harmful biological agents at museum workposts. They are: Aspergillus (A. niger, A. versicolor), Cladosporium (C. herbarum, C. macrocarpum), Penicillium (P. carneum, P. digitatum, P. italicum, P. paneum, P. polonicum), Rhizopus nigricans.

  7. Introduction to radiation biology

    International Nuclear Information System (INIS)

    Gensicke, F.

    1977-01-01

    The textbook is written with special regard to radiation protection of man. It shall enable the reader to assess the potential radiation risks to living organisms and lead him to an insight into radiation protection measures. The following topics are covered: physical fundamentals of ionizing radiations; physical and chemical fundamentals of biological radiation effects; radiation effects on cells, organs, organ systems, and whole animal organisms focussing on mammals and man; modification of radiation effects; chemical radiation protection; therapy of radiation injuries; radionuclide kinetics; biological radiation effects in connection with radiation hazards and with the limitation of radiation exposure. It is intended for vocational education of medical personnel

  8. Biological effects of radiation

    International Nuclear Information System (INIS)

    2013-01-01

    This fourth chapter presents: cell structure and metabolism; radiation interaction with biological tissues; steps of the production of biological effect of radiation; radiosensitivity of tissues; classification of biological effects; reversibility, transmissivity and influence factors; pre-natal biological effects; biological effects in therapy and syndrome of acute irradiation

  9. Biologic effects of electromagnetic radiation and microwave

    International Nuclear Information System (INIS)

    Deng Hua

    2002-01-01

    Electromagnetic radiation and microwave exist mankind's environment widely. People realize they disserve authors' health when authors make use of them. Electromagnetic radiation is one of the major physic factors which injure people's health. A review of the biologic mechanism about electromagnetic radiation and microwave, their harmful effects to human body, problems in authors' research and the prospect

  10. Advances in radiation biology

    International Nuclear Information System (INIS)

    Lett, J.T.; Ehmann, U.K.; Cox, A.B.

    1987-01-01

    The classical period of radiation biology is coming to a close. Such change always occurs at a time when the ideas and concepts that promoted the burgeoning of an infant science are no longer adequate. This volume covers a number of areas in which new ideas and research are playing a vital role, including cellular radiation sensitivity, radioactive waste disposal, and space radiation biology

  11. Radiation interactions with biological systems.

    Science.gov (United States)

    Islam, Muhammad Torequl

    2017-05-01

    The use of radiation, especially ionizing radiation (IR), is currently attracting great attention in the field of medical sciences. However, it should be mentioned that IR has both beneficial and harmful effects in biological systems. This review aims to focus on IR-mediated physiological events in a mechanistic way. Evidence from the databases, mainly from PUBMED and SCIENCE DIRECT were considered. IR directly and/or with their lyses products (indirect) causes oxidative stresses to biological systems. These activities may be localized and systematic. Otherwise, IR-induced non-/multi-targeted effects are also evident. IR in diagnosis and cancer radiotherapy is well-known. Reactive species produced by IR are not only beneficial, but also can exert harmful effects in a biological system such as aging, genetic instability and mutagenicity, membrane lysis and cell death, alteration of enzymatic activity and metabolic events, mitochondrial dysfunction, and even cancer. Additionally, DNA adducts formation, after IR-induced DNA breakage, is a cause of blockage of DNA repair capability with an increase in cellular radiosensitivity. These may allow cellular ruin even at low IR levels. Dependent on the dose, duration of action and quality, IR plays diverse roles in biological systems.

  12. Biological Effects of Ionizing Radiation

    Science.gov (United States)

    Ingram, M.; Mason, W. B.; Whipple, G. H.; Howland, J. W.

    1952-04-07

    This report presents a review of present knowledge and concepts of the biological effects of ionizing radiations. Among the topics discussed are the physical and chemical effects of ionizing radiation on biological systems, morphological and physiological changes observed in biological systems subjected to ionizing radiations, physiological changes in the intact animal, latent changes following exposure of biological systems to ionizing radiations, factors influencing the biological response to ionizing radiation, relative effects of various ionizing radiations, and biological dosimetry.

  13. Radiation biology at CRNL

    International Nuclear Information System (INIS)

    Myers, D.K.

    1986-01-01

    This paper gives a broad overview of radiation biology at Chalk River Nuclear Laboratories (CRNL). The research group consists of 8 professionals and approximately 12 support staff. Objectives of the group are listed. Current research programs discussed are: 1) recombinant dna technology; 2) the hyperthermia program; 3) cancer-prone families; 4) animal studies; and 5) assessment of radiation hazards

  14. Integrative radiation systems biology

    International Nuclear Information System (INIS)

    Unger, Kristian

    2014-01-01

    Maximisation of the ratio of normal tissue preservation and tumour cell reduction is the main concept of radiotherapy alone or combined with chemo-, immuno- or biologically targeted therapy. The foremost parameter influencing this ratio is radiation sensitivity and its modulation towards a more efficient killing of tumour cells and a better preservation of normal tissue at the same time is the overall aim of modern therapy schemas. Nevertheless, this requires a deep understanding of the molecular mechanisms of radiation sensitivity in order to identify its key players as potential therapeutic targets. Moreover, the success of conventional approaches that tried to statistically associate altered radiation sensitivity with any molecular phenotype such as gene expression proofed to be somewhat limited since the number of clinically used targets is rather sparse. However, currently a paradigm shift is taking place from pure frequentistic association analysis to the rather holistic systems biology approach that seeks to mathematically model the system to be investigated and to allow the prediction of an altered phenotype as the function of one single or a signature of biomarkers. Integrative systems biology also considers the data from different molecular levels such as the genome, transcriptome or proteome in order to partially or fully comprehend the causal chain of molecular mechanisms. An example for the application of this concept currently carried out at the Clinical Cooperation Group “Personalized Radiotherapy in Head and Neck Cancer” of the Helmholtz-Zentrum München and the LMU Munich is described. This review article strives for providing a compact overview on the state of the art of systems biology, its actual challenges, potential applications, chances and limitations in radiation oncology research working towards improved personalised therapy concepts using this relatively new methodology

  15. Development trend of radiation biology research-systems radiation biology

    International Nuclear Information System (INIS)

    Min Rui

    2010-01-01

    Radiation biology research has past 80 years. We have known much more about fundamentals, processes and results of biology effects induced by radiation and various factors that influence biology effects wide and deep, however many old and new scientific problems occurring in the field of radiation biology research remain to be illustrated. To explore and figure these scientific problems need systemic concept, methods and multi dimension view on the base of considerations of complexity of biology system, diversity of biology response, temporal and spatial process of biological effects during occurrence, and complex feed back network of biological regulations. (authors)

  16. Radiation chemistry comes before radiation biology.

    Science.gov (United States)

    O'Neill, Peter; Wardman, Peter

    2009-01-01

    This article seeks to illustrate some contributions of radiation chemistry to radiobiology and related science, and to draw attention to examples where radiation chemistry is central to our knowledge of specific aspects. Radiation chemistry is a mature branch of radiation science which is continually evolving and finding wider applications. This is particularly apparent in the study of the roles of free radicals in biology generally, and radiation biology specifically. The chemical viewpoint helps unite the spatial and temporal insight coming from radiation physics with the diversity of biological responses. While historically, the main application of radiation chemistry of relevance to radiation biology has been investigations of the free-radical processes leading to radiation-induced DNA damage and its chemical characterization, two features of radiation chemistry point to its wider importance. First, its emphasis on quantification and characterization at the molecular level helps provide links between DNA damage, biochemical repair processes, and mutagenicity and radiosensitivity. Second, its central pillar of chemical kinetics aids understanding of the roles of 'reactive oxygen species' in cell signalling and diverse biological effects more generally, and application of radiation chemistry in the development of drugs to enhance radiotherapy and as hypoxia-specific cytotoxins or diagnostic agents. The illustrations of the broader applications of radiation chemistry in this article focus on their relevance to radiation biology and demonstrate the importance of synergy in the radiation sciences. The past contributions of radiation chemistry to radiation biology are evident, but there remains considerable potential to help advance future biological understanding using the knowledge and techniques of radiation chemistry.

  17. Integrative Radiation Biology

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos-Hoff, Mary Helen [New York University School of Medicine, NY (United States)

    2015-02-27

    We plan to study tissue-level mechanisms important to human breast radiation carcinogenesis. We propose that the cell biology of irradiated tissues reveals a coordinated multicellular damage response program in which individual cell contributions are primarily directed towards suppression of carcinogenesis and reestablishment of homeostasis. We identified transforming growth factor β1 (TGFβ) as a pivotal signal. Notably, we have discovered that TGFβ suppresses genomic instability by controlling the intrinsic DNA damage response and centrosome integrity. However, TGFβ also mediates disruption of microenvironment interactions, which drive epithelial to mesenchymal transition in irradiated human mammary epithelial cells. This apparent paradox of positive and negative controls by TGFβ is the topic of the present proposal. First, we postulate that these phenotypes manifest differentially following fractionated or chronic exposures; second, that the interactions of multiple cell types in tissues modify the responses evident in this single cell type culture models. The goals are to: 1) study the effect of low dose rate and fractionated radiation exposure in combination with TGFβ on the irradiated phenotype and genomic instability of non-malignant human epithelial cells; and 2) determine whether stromal-epithelial interactions suppress the irradiated phenotype in cell culture and the humanized mammary mouse model. These data will be used to 3) develop a systems biology model that integrates radiation effects across multiple levels of tissue organization and time. Modeling multicellular radiation responses coordinated via extracellular signaling could have a significant impact on the extrapolation of human health risks from high dose to low dose/rate radiation exposure.

  18. Radiation biology: a century of hopes and disappointments

    International Nuclear Information System (INIS)

    Singh, B.B.

    1998-01-01

    In the history of science, radiation biology will rank perhaps as the most popular subject to have attracted researchers from many disciplines of basic as well as applied sciences. Apart from the excitement arising in clinics relating to radiation treatment of cancers the tragedies in Hiroshima and Nagasaki brought numerous scientists together to investigate the harmful biological effects of ionizing radiation. It is then radiation biology picked up a great momentum. It started developing in two different directions what may be called basic radiation biology and radiation biology applied to radiotherapy of cancer. While great strides were being made in basic radiation biology trying to understand the biological effects of radiation and mechanisms thereof, clinical aspect remained confined mainly to the medical fraternity where empiricalism became the rule

  19. Biology of ionizing radiation effects

    International Nuclear Information System (INIS)

    Ferradini, C.; Pucheault, J.

    1983-01-01

    The present trends in biology of ionizing radiation are reviewed. The following topics are investigated: interaction of ionizing radiations with matter; the radiolysis of water and aqueous solutions; properties of the free radicals intervening in the couples O 2 /H 2 O and H 2 O/H 2 ; radiation chemistry of biological compounds; biological effects of ionizing radiations; biochemical mechanisms involving free radicals as intermediates; applications (biotechnological applications, origins of life) [fr

  20. Biological radiation effects

    International Nuclear Information System (INIS)

    Sejourne, Michele.

    1977-01-01

    This work examines ionizing radiations: what they are, where they come from, their actions and consequences, finally the norms and preventive measures necessary to avoid serious contamination, whether the individual or the population in general is involved. Man has always been exposed to natural irradiation, but owing to the growing use of ionizing radiations both in medicine and in industry, not to mention nuclear tests and their use as an argument of dissuasion, the irradiation of human beings is increasing daily. Radioactive contamination does remain latent, apart from acute cases, but this is where the danger lies since the consequences may not appear until long after the irradiation. Of all biological effects due to the action of radioelements the genetic risk is one of the most important, affecting the entire population and especially the generations to come. The risk of cancer and leukemia induction plays a substantial part also since a large number of people may be concerned, depending on the mode of contamination involved. All these long-term dangers do not of course exclude the various general or local effects to which the individual alone may be exposed and which sometimes constitute a threat to life. As a result the use of ionizing radiations must be limited and should only be involved if no other process can serve instead. The regulations governing radioelements must be stringent and their application strictly supervised for the better protection of man. This protection must be not only individual but also collective since pollution exists in air, water and land passes to plants and animals and finally reaches the last link in the food chain, man [fr

  1. Radiation protection standards: a summary of the biological effects of ionising radiation and principles of radiation protection

    International Nuclear Information System (INIS)

    1994-01-01

    This leaflet in the NRPB At-a-Glance-Series briefly summarises the biological effects of radiation, harm and sensitivity to radiation, radiation protection principles, acceptability of risk and the control of doses to workers, the public and in medical procedures in the UK. (UK)

  2. Biological effects of ionizing radiation

    International Nuclear Information System (INIS)

    Marko, A.M.

    1981-05-01

    In this review radiation produced by the nuclear industry is placed into context with other sources of radiation in our world. Human health effects of radiation, derivation of standards and risk estimates are reviewed in this document. The implications of exposing the worker and the general population to radiation generated by nuclear power are assessed. Effects of radiation are also reviewed. Finally, gaps in our knowledge concerning radiation are identified and current research on biological effects, on environmental aspects, and on dosimetry of radiation within AECL and Canada is documented in this report. (author)

  3. Biological implications of radiation

    International Nuclear Information System (INIS)

    Bond, V.P.

    1977-01-01

    Some topics discussed are as follows: effects of diagnostic and therapeutic radiation on dividing cells, DNA, and blood cells; radiation sickness in relation to dose; early and late effects of radiation; effects of low dose irradiation; dose-effect curves; radioinduction of tumors in animals; and incidence of cancer in children following in utero exposure to diagnostic x rays

  4. Biological radiation effects

    International Nuclear Information System (INIS)

    Gomes, R.A.

    1976-01-01

    The stages of processes leading to radiation damage are studied, as well as, the direct and indirect mechanics of its production. The radiation effects on nucleic acid and protein macro moleculas are treated. The physical and chemical factors that modify radiosensibility are analysed, in particular the oxygen effects, the sensibilization by analogues of nitrogen bases, post-effects, chemical protection and inherent cell factors. Consideration is given to restoration processes by excision of injured fragments, the bloching of the excision restoration processes, the restoration of lesions caused by ionizing radiations and to the restoration by genetic recombination. Referring to somatic effects of radiation, the early ones and the acute syndrome of radiation are discussed. The difference of radiosensibility observed in mammalian cells and main observable alterations in tissues and organs are commented. Referring to delayed radiation effects, carcinogeneses, alterations of life span, effects on growth and development, as well as localized effects, are also discussed [pt

  5. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    Hall, E.J.; Zaider, M.

    1991-05-01

    Research at the Radiological Research Laboratory is a blend of physics, chemistry, and biology, involving research at the basic level with the admixture of a small proportion of pragmatic or applied research in support of radiation protection and/or radiotherapy. Current research topics include: oncogenic transformation assays, mutation studies involving interactions between radiation and environmental contaminants, isolation, characterization and sequencing of a human repair gene, characterization of a dominant transforming gene found in C3H 10T1/2 cells, characterize ab initio the interaction of DNA and radiation, refine estimates of the radiation quality factor Q, a new mechanistic model of oncogenesis showing the role of long-term low dose medium LET radiation, and time dependent modeling of radiation induced chromosome damage and subsequent repair or misrepair

  6. Review of domestic radiation biology research

    International Nuclear Information System (INIS)

    Zheng Chun; Song Lingli; Ai Zihui

    2011-01-01

    Radiation biology research in China during the past ten years are reviewed. It should be noticed that radiation-biology should focus on microdosimetry, microbeam application, and radiation biological mechanism. (authors)

  7. The biological effects of radiation

    International Nuclear Information System (INIS)

    Sykes, D.A.

    1979-01-01

    The hazards of radiations to man are briefly covered in this paper. The natural background sources of radiations are stated and their resulting doses are compared to those received voluntarily by man. The basis of how radiations cause biological damage is given and the resulting somatic effects are shown for varying magnitude of dose. Risk estimates are given for cancer induction and genetic effects are briefly discussed. Finally four case studies of radiation damage to humans are examined exemplifying the symptoms of large doses of radiations [af

  8. Radiation chemistry in development and research of radiation biology

    International Nuclear Information System (INIS)

    Min Rui

    2010-01-01

    During the establishment and development of radiation biology, radiation chemistry acts like bridge which units the spatial and temporal insight coming from radiation physics with radiation biology. The theory, model, and methodology of radiation chemistry play an important role in promoting research and development of radiation biology. Following research development of radiation biology effects towards systems radiation biology the illustration and exploration both diversity of biological responses and complex process of biological effect occurring remain to need the theory, model, and methodology come from radiation chemistry. (authors)

  9. Biology relevant to space radiation

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1996-01-01

    The biological effects of the radiations to which mankind on earth are exposed are becoming known with an increasing degree of detail. This knowledge is the basis of the estimates of risk that, in turn, fosters a comprehensive and evolving radiation protection system. The substantial body of information has been, and is being, applied to questions about the biological effects of radiation is space and the associated risk estimates. The purpose of this paper is not to recount all the biological effect of radiation but to concentrate on those that may occur as a result from exposure to the radiations encountered in space. In general, the biological effects of radiation in space are the same as those on earth. However, the evidence that the effects on certain tissues by the heaviest-charged particles can be interpreted on the basis of our knowledge about other high-LET radiation is equivocal. This specific question will be discussed in greater detail later. It is important to point out the that there are only limited data about the effects on humans of two components of the radiations in space, namely protons and heavy ions. Thus predictions of effects on space crews are based on experimental systems exposed on earth at rates and fluences that are higher than those in space and one the effects of gamma or x rays with estimates of the equivalent doses using quality factors

  10. Biological protection against nuclear radiation

    International Nuclear Information System (INIS)

    Mateescu, Silvia; Stanciu, Marcela

    2001-01-01

    This monograph is addressed to physicists, chemists, engineers, under-, graduated and enrolled towards PhD degree students, wishing to orient their activity towards research, design, education or production in nuclear power and nuclear technology field. Specifically, the work deals with the biological protection against nuclear radiations. The chapter 1 presents selectively the nuclear radiation types, the interaction of neutrons, gamma radiations and charged particles with matter. Particularly focused is the issue of biological effects of nuclear radiations and the implied permissible limits of irradiation. Chapter 2 describes one of the most intense sources of nuclear radiation, namely, the reactor core; reviewed are the reactor neutron spectra, as well as, the spectra of primary and secondary radiations. Chapter 3 deals with the activation process as a source of nuclear radiations; analyzed are the processes of activation of coolant, structural elements and soils, as well as the tritium production. Chapter 4 treats the nuclear fission process and formation of fission products, another major source of radiations. The principal features of fission products are mentioned such as: decay characteristics, fission yields, fission product activity, decay heat. Chapter 5 tackles the problem of influence of geometric form of the source upon radiation flux spatial distribution. In chapter 6 briefly are described the elements of neutron transport theory, diffusion equation, neutron slowing-down, age theory, i.e. all the knowledge implied in neutron attenuation calculation in shields. Chapter 7 deals with gamma radiation attenuation in shields, namely, spatial distribution of gamma-ray dose rates from point-like sources in an infinite medium, gamma radiation build-up factors, etc. In chapter 8 the phenomenon of heating of biological shields due to nuclear radiation is described. Calculation of heat rate generated by gamma and neutron radiation is sketched. Chapter 9 treats

  11. Biological monitoring of radiation exposure

    Science.gov (United States)

    Horneck, G.

    1998-11-01

    Complementary to physical dosimetry, biological dosimetry systems have been developed and applied which weight the different components of environmental radiation according to their biological efficacy. They generally give a record of the accumulated exposure of individuals with high sensitivity and specificity for the toxic agent under consideration. Basically three different types of biological detecting/monitoring systems are available: (i) intrinsic biological dosimeters that record the individual radiation exposure (humans, plants, animals) in measurable units. For monitoring ionizing radiation exposure, in situ biomarkers for genetic (e.g. chromosomal aberrations in human lymphocytes, germ line minisatellite mutation rates) or metabolic changes in serum, plasma and blood (e.g. serum lipids, lipoproteins, lipid peroxides, melatonin, antibody titer) have been used. (ii) Extrinsic biological dosimeters/indicators that record the accumulated dose in biological model systems. Their application includes long-term monitoring of changes in environmental UV radiation and its biological implications as well as dosimetry of personal UV exposure. (iii) Biological detectors/biosensors for genotoxic substances and agents such as bacterial assays (e.g. Ames test, SOS-type test) that are highly sensitive to genotoxins with high specificity. They may be applicable for different aspects in environmental monitoring including the International Space Station.

  12. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood ''biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons

  13. Radiation physics, biophysics, and radiation biology

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  14. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    Hall, E.J.

    1992-05-01

    The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent

  15. Radiation biology of mosquitoes.

    Science.gov (United States)

    Helinski, Michelle E H; Parker, Andrew G; Knols, Bart G J

    2009-11-16

    There is currently renewed interest in assessing the feasibility of the sterile insect technique (SIT) to control African malaria vectors in designated areas. The SIT relies on the sterilization of males before mass release, with sterilization currently being achieved through the use of ionizing radiation. This paper reviews previous work on radiation sterilization of Anopheles mosquitoes. In general, the pupal stage was irradiated due to ease of handling compared to the adult stage. The dose-response curve between the induced sterility and log (dose) was shown to be sigmoid, and there was a marked species difference in radiation sensitivity. Mating competitiveness studies have generally been performed under laboratory conditions. The competitiveness of males irradiated at high doses was relatively poor, but with increasing ratios of sterile males, egg hatch could be lowered effectively. Males irradiated as pupae had a lower competitiveness compared to males irradiated as adults, but the use of partially-sterilizing doses has not been studied extensively. Methods to reduce somatic damage during the irradiation process as well as the use of other agents or techniques to induce sterility are discussed. It is concluded that the optimal radiation dose chosen for insects that are to be released during an SIT programme should ensure a balance between induced sterility of males and their field competitiveness, with competitiveness being determined under (semi-) field conditions. Self-contained 60Co research irradiators remain the most practical irradiators but these are likely to be replaced in the future by a new generation of high output X ray irradiators.

  16. Radiation biology of mosquitoes

    Directory of Open Access Journals (Sweden)

    Knols Bart GJ

    2009-11-01

    Full Text Available Abstract There is currently renewed interest in assessing the feasibility of the sterile insect technique (SIT to control African malaria vectors in designated areas. The SIT relies on the sterilization of males before mass release, with sterilization currently being achieved through the use of ionizing radiation. This paper reviews previous work on radiation sterilization of Anopheles mosquitoes. In general, the pupal stage was irradiated due to ease of handling compared to the adult stage. The dose-response curve between the induced sterility and log (dose was shown to be sigmoid, and there was a marked species difference in radiation sensitivity. Mating competitiveness studies have generally been performed under laboratory conditions. The competitiveness of males irradiated at high doses was relatively poor, but with increasing ratios of sterile males, egg hatch could be lowered effectively. Males irradiated as pupae had a lower competitiveness compared to males irradiated as adults, but the use of partially-sterilizing doses has not been studied extensively. Methods to reduce somatic damage during the irradiation process as well as the use of other agents or techniques to induce sterility are discussed. It is concluded that the optimal radiation dose chosen for insects that are to be released during an SIT programme should ensure a balance between induced sterility of males and their field competitiveness, with competitiveness being determined under (semi- field conditions. Self-contained 60Co research irradiators remain the most practical irradiators but these are likely to be replaced in the future by a new generation of high output X ray irradiators.

  17. Occurrence, Biology and Harmfulness of Byctiscus betulae (L. (Coleoptera, Rhynchitidae

    Directory of Open Access Journals (Sweden)

    Jaroslav Urban

    2015-01-01

    Full Text Available In 2012 and 2013, was studied the occurrence, biology and harmfulness of Byctiscus betulae (L. (Rhynchitidae on forest woody plants in the Brno region. Leaf rolls were found on 13 species (and 10 genera of woody plants. Most frequently, they occurred on Fagus sylvatica, Tilia spp. (namely on T. cordata, Salix caprea and Populus tremula. The beetles hibernate in ground pupal chambers and appear on woody plants in the last decade of April. After hibernation, females live on average seven (males five weeks, and damage on average 40 (males 25 cm2 of leaves. The females create leaf rolls on annual shoots they have gnawed, exceptionally (in 2% on leaves with damaged petioles. In the rolls on F. sylvatica, they roll on average 5.6 leaves whose total average area is 49.5 cm2 and lay on average 5.1 eggs. In the rolls on Tilia spp., they roll on average 3.3 leaves whose total area is 63.2 cm2 and lay on average 4.9 eggs. In the rolls on S. caprea, they roll on average 3.3 leaves whose total area is 38.3 cm2 and lay on average 3.5 eggs. The maximum number of laid eggs (on average 8.0 was observed in the leaf rolls on Vitis vinifera. The average number of eggs in the leaf rolls was decreasing from May to July. The number of eggs was increasing with the increasing total leaf area rolled. The females lay on average 50 eggs. On P. tremula, S. caprea and Pyrus pyraster they create about 15 leaf rolls, on F. sylvatica and Tilia spp. about 10 leaf rolls and on V. vinifera ca. 8 leaf rolls. Embryogenesis lasts from 8 to 9 days. Larvae develop over 3 instars and damage ca. 300 mm2 of leaves. Coming of age within 4−7 weeks, they leave the leaf rolls from mid-June to the beginning of September.

  18. Biological Sensors for Solar Ultraviolet Radiation

    Directory of Open Access Journals (Sweden)

    André P. Schuch

    2011-04-01

    Full Text Available Solar ultraviolet (UV radiation is widely known as a genotoxic environmental agent that affects Earth ecosystems and the human population. As a primary consequence of the stratospheric ozone layer depletion observed over the last decades, the increasing UV incidence levels have heightened the concern regarding deleterious consequences affecting both the biosphere and humans, thereby leading to an increase in scientific efforts to understand the role of sunlight in the induction of DNA damage, mutagenesis, and cell death. In fact, the various UV-wavelengths evoke characteristic biological impacts that greatly depend on light absorption of biomolecules, especially DNA, in living organisms, thereby justifying the increasing importance of developing biological sensors for monitoring the harmful impact of solar UV radiation under various environmental conditions. In this review, several types of biosensors proposed for laboratory and field application, that measure the biological effects of the UV component of sunlight, are described. Basically, the applicability of sensors based on DNA, bacteria or even mammalian cells are presented and compared. Data are also presented showing that on using DNA-based sensors, the various types of damage produced differ when this molecule is exposed in either an aqueous buffer or a dry solution. Apart from the data thus generated, the development of novel biosensors could help in evaluating the biological effects of sunlight on the environment. They also emerge as alternative tools for using live animals in the search for protective sunscreen products.

  19. Biological Sensors for Solar Ultraviolet Radiation

    Science.gov (United States)

    Yagura, Teiti; Makita, Kazuo; Yamamoto, Hiromasa; Menck, Carlos F.M.; Schuch, André P.

    2011-01-01

    Solar ultraviolet (UV) radiation is widely known as a genotoxic environmental agent that affects Earth ecosystems and the human population. As a primary consequence of the stratospheric ozone layer depletion observed over the last decades, the increasing UV incidence levels have heightened the concern regarding deleterious consequences affecting both the biosphere and humans, thereby leading to an increase in scientific efforts to understand the role of sunlight in the induction of DNA damage, mutagenesis, and cell death. In fact, the various UV-wavelengths evoke characteristic biological impacts that greatly depend on light absorption of biomolecules, especially DNA, in living organisms, thereby justifying the increasing importance of developing biological sensors for monitoring the harmful impact of solar UV radiation under various environmental conditions. In this review, several types of biosensors proposed for laboratory and field application, that measure the biological effects of the UV component of sunlight, are described. Basically, the applicability of sensors based on DNA, bacteria or even mammalian cells are presented and compared. Data are also presented showing that on using DNA-based sensors, the various types of damage produced differ when this molecule is exposed in either an aqueous buffer or a dry solution. Apart from the data thus generated, the development of novel biosensors could help in evaluating the biological effects of sunlight on the environment. They also emerge as alternative tools for using live animals in the search for protective sunscreen products. PMID:22163847

  20. Biological control of Microcystis dominated harmful algal blooms ...

    African Journals Online (AJOL)

    Freshwater resources are now threatened by the presence and increase of harmful algal blooms (HAB) all over the world. The HABs are sometimes a direct result of anthropogenic pollution entering water bodies, such as partially treated nutrient-rich effluents and the leaching of fertilisers and animal wastes. The impact of ...

  1. Biology with neutron radiation

    International Nuclear Information System (INIS)

    Zaccai, Giuseppe

    1993-01-01

    Neutron diffraction, elastic and inelastic neutron scattering experiments provide important information on the structure, interactions and dynamics of biological molecules. This arises from the unique properties of the neutron and of its interaction with matter. Coherent and incoherent neutron scattering amplitudes and cross-sections are very different for H and 2 H (deuterium). Deuterium labelling by chemical or biochemical methods and H 2 O: 2 H 2 O exchange is the basis of high resolution crystallography experiments to locate functionally important H-atoms in protein molecules. It is also very important in low resolution crystallography and small angle scattering experiments to solve large complex structures, such as protein-nucleic acid complexes or biological membrane systems, by using contrast variation techniques. The energies of neutrons with a wavelength of the order of 1 - 10 A are similar to thermal energies and inelastic neutron scattering experiments have been done with different energy resolutions (≥∼ 1 μeV) to characterise the functional dynamics of proteins in solution and in membranes. (author)

  2. Progress in radiation biology

    International Nuclear Information System (INIS)

    Masuda, Koji; Zingu, Kenichi; Matsuura, Keiichi; Aramaki, Ryoji; Yoshinaga, Haruma

    1980-01-01

    Possible mechanism of differences in radiosensitivity of malignant tumors in vivo was reviewed. The magnitude of repair of potentially lethal damage after X- or gamma-ray was relatively large for melanoma, osteosarcoma and glioblastoma multiform cultured in vitro. The proportion of hypoxic cells in malignant melanoma was relatively high and the Dq value of the dose response curves was relatively large, implying that these two factors also play important role for making malignant melanoma radioresistant. Recurrent tumor cells in vitro has relatively high amount of non-protein SH, which can protect cells from radiation. Except for these limited data, no experimental results has been reported which can explain the radiobiological mechanism of each radioresistant tumor. It was stressed that assessment of the radiobiological mechanism of the relatively radioresistant malignant tumors in vivo and new treatment protocol based on this assessment will improve the local control rate of malignant tumors in vivo as well as doing best in treating relatively radiosensitive tumors. (author)

  3. Biological physics and synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Filhol, J.M.; Chavanne, J. [European Synchrotron Radiation Facility, 38 - Grenoble (France); Weckert, E. [Hasylab at Desy, Hamburg (Germany)] [and others

    2001-07-01

    This conference deals with the applications of synchrotron radiation to current problems in biology and medicine. Seven sessions take stock on the subject: sources and detectors; inelastic scattering and dynamics; muscle diffraction; reaction mechanisms; macromolecular assemblies; medical applications; imaging and spectroscopy. The document presents the papers abstracts. (A.L.B.)

  4. Biological physics and synchrotron radiation

    International Nuclear Information System (INIS)

    Filhol, J.M.; Chavanne, J.; Weckert, E.

    2001-01-01

    This conference deals with the applications of synchrotron radiation to current problems in biology and medicine. Seven sessions take stock on the subject: sources and detectors; inelastic scattering and dynamics; muscle diffraction; reaction mechanisms; macromolecular assemblies; medical applications; imaging and spectroscopy. The document presents the papers abstracts. (A.L.B.)

  5. Emerging frontiers in radiation biology

    International Nuclear Information System (INIS)

    Singh, B.B.

    1996-01-01

    Radiation biology owes its origin to the spectacular success in the treatment of human diseases by x-rays and radium, just after their respective discoveries in 1895-96. From the very inception it has attracted researchers from all disciplines of science. The target and hit theory developed by physicists, dominated the scene till the advent of radiation chemistry concepts which offered an entirely different perspective to the mechanisms involved in biological effects of radiations and their modification by endogenous and exogenous agents like radioprotectors and radiosensitisers including hyperthermia. The applied aspect of radiation biology mainly relates to radiation therapy of cancer which, in spite of its long existence, is still to achieve scientific perfection. Nevertheless, it did not wait -and fortunately so-, for its radiobiological rationality but continued its development to be the main modality for cancer treatment today. Several approaches are now being attempted to improve its efficacy by selectively damaging the cancerous cells while sparing the normal tissues and also by devising suitable predictive assays for radioresponse of different tumours to enable individualisation of treatment schedules. (author). 99 refs., 1 fig., 2 tabs

  6. Biological Research for Radiation Protection

    International Nuclear Information System (INIS)

    Kim, In Gyu; Kim, Kug Chan; Jung, Il Lae; Choi, Yong Ho; Kim, Jin Sik; Moon, Myung Sook; Byun, Hee Sun; Phyo, Ki Heon; Kim, Sung Keun

    2005-04-01

    The work scope of 'Biological Research for the Radiation Protection' had contained the research about ornithine decarboxylase and its controlling proteins, thioredoxin, peroxiredoxin, S-adenosymethionine decarboxylase, and glutamate decarboxylase 67KD effect on the cell death triggered ionizing radiation and H 2 O 2 (toxic agents). In this study, to elucidate the role of these proteins in the ionizing radiation (or H 2 O 2 )-induced apoptotic cell death, we utilized sensesed (or antisensed) cells, which overexpress (or down-regulate) RNAs associated with these proteins biosynthesis, and investigated the effects of these genes on the cytotoxicity caused by ionizing radiation and H 2 O 2 (or paraquat). We also investigated whether genisteine(or thiamine) may enhance the cytotoxic efficacy of tumor cells caused by ionizing radiation (may enhance the preventing effect radiation or paraquat-induced damage) because such compounds are able to potentiate the cell-killing or cell protecting effects. Based on the above result, we suggest that the express regulation of theses genes have potentially importance for sensitizing the efficiency of radiation therapy of cancer or for protecting the radiation-induced damage of normal cells

  7. Biological Research for Radiation Protection

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Gyu; Kim, Kug Chan; Jung, Il Lae; Choi, Yong Ho; Kim, Jin Sik; Moon, Myung Sook; Byun, Hee Sun; Phyo, Ki Heon; Kim, Sung Keun

    2005-04-15

    The work scope of 'Biological Research for the Radiation Protection' had contained the research about ornithine decarboxylase and its controlling proteins, thioredoxin, peroxiredoxin, S-adenosymethionine decarboxylase, and glutamate decarboxylase 67KD effect on the cell death triggered ionizing radiation and H{sub 2}O{sub 2}(toxic agents). In this study, to elucidate the role of these proteins in the ionizing radiation (or H{sub 2}O{sub 2})-induced apoptotic cell death, we utilized sensesed (or antisensed) cells, which overexpress (or down-regulate) RNAs associated with these proteins biosynthesis, and investigated the effects of these genes on the cytotoxicity caused by ionizing radiation and H{sub 2}O{sub 2}(or paraquat). We also investigated whether genisteine(or thiamine) may enhance the cytotoxic efficacy of tumor cells caused by ionizing radiation (may enhance the preventing effect radiation or paraquat-induced damage) because such compounds are able to potentiate the cell-killing or cell protecting effects. Based on the above result, we suggest that the express regulation of theses genes have potentially importance for sensitizing the efficiency of radiation therapy of cancer or for protecting the radiation-induced damage of normal cells.

  8. Clinical oncology based upon radiation biology

    International Nuclear Information System (INIS)

    Hirata, Hideki

    2016-01-01

    This paper discussed the biological effects of radiation as physical energy, especially those of X-ray as electromagnetic radiation, by associating the position of clinical oncology with classical radiation cell biology as well as recent molecular biology. First, it described the physical and biological effects of radiation, cell death due to radiation and recovery, radiation effects at tissue level, and location information and dosage information in the radiotherapy of cancer. It also described the territories unresolved through radiation biology, such as low-dose high-sensitivity, bystander effects, etc. (A.O.)

  9. Biological effects of ionizing radiation

    International Nuclear Information System (INIS)

    Gisone, Pablo; Perez, Maria R.

    2001-01-01

    It has been emphasised the importance of DNA as the main target for ionizing radiation, that can induce damage by its direct action on this molecule or by an indirect effect mediated by free-radicals generated by water radiolysis. Biological effects of ionizing radiation are influenced not only by the dose but also by the dose-rate and the radiation quality. Radiation induced damage, mainly DNA single and double strand breaks, is detected by molecular sensors which in turn trigger signalling cascades leading to cell cycle arrest to allow DNA repair or programmed cell death (apoptosis). Those effects related with cell death, named deterministic, exhibits a dose-threshold below which they are not observed. Acute radiation syndrome and radiological burns are examples of this kind of effects. Other radiation induced effects, called stochastic, are the consequence of cell transformation and do not exhibit a dose-threshold. This is the case of cancer induction and hereditary effects. The aim of this presentation is briefly describe the main aspects of deterministic and stochastic effects from the point of view of radiobiology and radio pathology. (author)

  10. Can the ionizing radiation and sunlight be harmful to health?

    International Nuclear Information System (INIS)

    Pesmen, Curt

    2008-01-01

    We're all exposed to radiation sources: the sun, X-rays, mammograms, CT scans, dental exams, even soil and we're just now finding out whether those rays, combined, are dangerous. Scientists are still figuring that out and they tend to disagree about the risks. But they recently found worrying signs that radiation exposure is on the rise, thanks largely to the popularity of high-tech medical exams such as CT scans. So it's wise to limit exposure as possible. The odds of developing cancer from radiation exposure are very small, but risks do rise the younger a person is radiated. There is a radiation footprint for every person. Some scientists do not believe any level of radiation is necessarily safe. At some time in life anyone will need a radiation-based medical treatment or diagnostic test. Radiation therapy may be the best way to shrink a cancer or save a life. A recent study warned that up to one-third of all CT scans may be medically unnecessary. Frequent flying theoretically ups cancer risks. After all, seven miles above sea level, there is much less atmosphere to absorb radiation from the sun.

  11. Biology relevant to space radiation

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1997-01-01

    There are only very limited data on the health effects to humans from the two major components of the radiations in space, namely protons and heavy ions. As a result, predictions of the accompanying effects must be based either on (1) data generated through studies of experimental systems exposed on earth at rates and fluences higher than those in space, or (2) extrapolations from studies of gamma and x rays. Better information is needed about the doses, dose rates, and the energy and LET spectra of the radiations at the organ level that are anticipated to be encountered during extended space missions. In particular, there is a need for better estimates of the relationship between radiation quality and biological effects. In the case of deterministic effects, it is the threshold that is important. The possibility of the occurrence of a large solar particle event (SPE) requires that such effects be considered during extended space missions. Analyses suggest, however, that it is feasible to provide sufficient shielding so as to reduce such effects to acceptable levels, particularly if the dose rates can be limited. If these analyses prove correct, the primary biological risks will be the stochastic effects (latent cancer induction). The contribution of one large SPE to the risk of stochastic effects while undesirable will not be large in comparison to the potential total dose on a mission of long duration

  12. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    Hall, E.J.; Zaider, M.; Delegianis, M.J.

    1989-07-01

    An important event of the year was the designation of our Laboratory as a Center for Radiological Research by the Dean of the Faculty of Medicine and Vice-President for Health Sciences. Center status acknowledges the size and importance of the research efforts in this area, and allows a greater measure of independence in administrative matters. While the name has changed from a Laboratory to a Center within the Medical School, the mission and charge remain the same. The efforts of the Center are a multidisciplinary mix of physics, chemistry, and biology, mostly at a basic level, with the admixture of a small proportion of pragmatic or applied research in support of radiation protection or radiation therapy. About a quarter of our funding, mostly individual research awards, could be regarded as in direct support of radiotherapy, with the remainder (an NCI program project grant and DOE grants) being in support of research addressing more basic issues. An important effort currently underway concerns ab-initio calculations of the dielectric response function of condensed water. This investigation has received the coveted designation, ''Grand Challenge Project,'' awarded by DOE to research work which represents ''distinct advance on a major scientific or engineering problem that is broadly recognized as important within the mission of the Department.''

  13. Development of radiation biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil; Son, Young Sook; Kim, Soo Kwan; Jang, Won Suk; Le, Sun Joo; Jee, Young Heun; Jung, Woo Jung

    1999-04-01

    Up until now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline (triage) to be able to be treated the victims as fast as possible. We established the premature chromosome condensation assay and apoptotic fragment assay which was the significant relationship between dose and cell damages to evaluate the irradiation dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with conventional chromosome aberration assay and micronuclei assay.

  14. A Model for Protective Behavior against the Harmful Effects of Radiation based on Medical Institution Classifications

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Ok; Kwon, Deok Mun [Daegu Health College, Daegu (Korea, Republic of); Dong, Kyung Rae [Gwangju Health College University, Gwangju (Korea, Republic of); Han, Seung Moo [Kyung Hee University, Seoul (Korea, Republic of)

    2010-12-15

    This study surveyed a total of 1,322 radiation technologist in health care institutions throughout Korea. This is a comparative study conducted on the levels of protective behavior against the harmful effects of radiation in heath care institutions which indicated that university hospitals and general hospitals showed higher level of protective behavior than for medical practitioners. This study found university hospitals have the following 7 characteristics to manage protective behavior against the harmful effects of radiation, protective environment, self-efficacy by distinction of task , self-efficacy, expectation of the protective behavior, the number of patients, level of the education related to the protection of the harmful effects of radiation and protective attitude. While general hospitals have the following 3 characteristics protective environment, expectation of the protective behavior and protective attitude. Hospitals have the following 4 characteristics protective environment, expectation of the protective behavior, protective attitude and self-efficacy and medical clinics have characteristics protective environment.

  15. A Model for Protective Behavior against the Harmful Effects of Radiation based on Medical Institution Classifications

    International Nuclear Information System (INIS)

    Han, Eun Ok; Kwon, Deok Mun; Dong, Kyung Rae; Han, Seung Moo

    2010-01-01

    This study surveyed a total of 1,322 radiation technologist in health care institutions throughout Korea. This is a comparative study conducted on the levels of protective behavior against the harmful effects of radiation in heath care institutions which indicated that university hospitals and general hospitals showed higher level of protective behavior than for medical practitioners. This study found university hospitals have the following 7 characteristics to manage protective behavior against the harmful effects of radiation, protective environment, self-efficacy by distinction of task , self-efficacy, expectation of the protective behavior, the number of patients, level of the education related to the protection of the harmful effects of radiation and protective attitude. While general hospitals have the following 3 characteristics protective environment, expectation of the protective behavior and protective attitude. Hospitals have the following 4 characteristics protective environment, expectation of the protective behavior, protective attitude and self-efficacy and medical clinics have characteristics protective environment

  16. Radiation is not always harmful to human health

    International Nuclear Information System (INIS)

    Thomas, R.G.

    1995-01-01

    The U.S. populace seems to associate the word radiation synonymously with the word doom. There is good reason for this as the media, special-interest groups, our regulatory agencies, and the ever-present litigious atmosphere exude doom whenever radiation is mentioned. The organizations that establish our radiation guidelines are also at fault as they continue to set levels that are coincident with the mood of the populace. Some of the most extensive epidemiological studies of the effects of ionizing radiation in humans have failed to conclude that there are health effects below whole-body equivalent radiation doses of 0.2 Gy (20 rads). This has been demonstrated in the study of survivors of the bombings in Japan; in the cases of radium dial painters (luminizers) studied in the United States, this value is 10 Gy (1000 rads). The luminizer data comprise the major portion of the discussion in this paper, but it must be emphasized that agency support for this program was severed in 1993, and these valuable data records currently lie unavailable for scientific use

  17. Biological research for radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Gyu; Kim, Kug Chan; Shim, Hae Won; Oh, Tae Jeong; Park, Seon Young; Lee, Kang Suk

    2000-04-01

    The work scope of Biological research for the radiation protection had contained the search of biological microanalytic methods for assessing the health effect by {gamma}-radiation and toxic agents, the standardization of human T-lymphocyte cell culture and polymerase chain reaction, T-cell clonal assay, and the quantification of mutation frequency in the hypoxanthine (guanine) phosphoribosyl transferase (HPRT) gene locus by single exposure or combined exposure. Especially, the polymerase chain reaction methods using reverse transcriptase has been developed to analyze the mutant gene induced by {gamma}-radiation and chemical (pentachlorophenol) agent exposure, and to investigate the point mutations in the HPRT gene locus of T-lymphocytes. The HPRT T-cell clonal assay revealed that it could not differentiate {gamma}-irradiation from pentachlorophenol, because the frequency of somatic mutations induced by both damaging agents increased in a dose-dependent manner. The analysis of DNA sequence alterations of HPRT mutant clones clearly showed that both damaging agents induced different mutational spectra in the HPRT locus of T-cells. The large deletions, which account for 75 percent of the analyzed mutants, are characteristic mutations induced by {gamma}-irradiation. By contrast, point mutations such as base substitutions and insertion, come up to 97 percent in the case of pentachlorophenol-treated cells. The point mutation frequencies at 190 base pair and 444 base pair positions are 3-6 folds as high as in those at other mutation positions. It may be that these mutation sites are hot spots induced by pentachlorophenol. These results suggest that the HPRT mutation spectrum can be used as a potential bio marker for assessing a specific environmental risk. (author)

  18. E. Biological effects of radiation on man

    International Nuclear Information System (INIS)

    1976-01-01

    This report firstly summarises information on the biological hazards of radiation and their relation to radiation dose, and hence estimates the biological risks associated with nuclear power production. Secondly, it describes the basis and present status of radiation protection standards in the nuclear power industry

  19. Infrared Radiography: Modeling X-ray Imaging without Harmful Radiation

    Science.gov (United States)

    Zietz, Otto; Mylott, Elliot; Widenhorn, Ralf

    2015-01-01

    Planar x-ray imaging is a ubiquitous diagnostic tool and is routinely performed to diagnose conditions as varied as bone fractures and pneumonia. The underlying principle is that the varying attenuation coefficients of air, water, tissue, bone, or metal implants within the body result in non-uniform transmission of x-ray radiation. Through the…

  20. Biological improvement of radiation resistance

    Energy Technology Data Exchange (ETDEWEB)

    Chun, K. J.; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J

    2000-08-01

    To investigate the mechanisms of gene action related to the radiation resistance in microorganisms could be essentially helpful for the development of radiation protectants and hormeric effects of low dose radiation. This book described isolation of radiation-resistant microorganisms, induction of radiation-resistant and functionally improved mutants by gamma-ray radiation, cloning and analysis of the radiation resistance related genes and analysis of the expressed proteins of the radiation resistant related genes.

  1. Biological improvement of radiation resistance

    International Nuclear Information System (INIS)

    Chun, K. J.; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.

    2000-08-01

    To investigate the mechanisms of gene action related to the radiation resistance in microorganisms could be essentially helpful for the development of radiation protectants and hormeric effects of low dose radiation. This book described isolation of radiation-resistant microorganisms, induction of radiation-resistant and functionally improved mutants by gamma-ray radiation, cloning and analysis of the radiation resistance related genes and analysis of the expressed proteins of the radiation resistant related genes

  2. Radiation biology for the non-biologist

    International Nuclear Information System (INIS)

    Myers, D.K.

    1978-06-01

    This colloquium introduces some of the general concepts used in cell biology and in the study of the effects of ionizing radiation on living organisms. The present research activities in radiation biology in the Biology Branch at the Chalk River Nuclear Laboratories cover a broad range of interests in the entire chain of events by which the initial radiation-induced changes in the living cell are translated into significant biological effects, including the eventual production of cancers and hereditary defects. The main theme of these research activities is an understanding of the mechanisms by which radiation damage to DNA (the carrier of hereditary information in all living organisms) can be actively repaired by the living cell. Advances in our understanding of these processes have broad implications for other areas of biology but also bear directly on the assessment of the biological hazards of ionizing radiation. The colloquium concludes with a brief discussion of the hazards of low-level radiation. (author)

  3. Detection of Sources of Harmful Radiation using Portable Sensors

    Science.gov (United States)

    2016-05-01

    background radiation. This is a common circumstance in cluttered urban envi- ronments. It is also in these environments where weapons such as dirty bombs...nuclear materials is key in preventing the proliferation of nuclear weapons and nuclear terror attacks. Terrorist organizations and even certain...countries acquiring nuclear weapons is a dangerous situation for the entire international community[12]. The smuggling of weapons such as tactical nuclear

  4. Radiation biology for pediatric radiologists

    International Nuclear Information System (INIS)

    Hall, Eric J.

    2009-01-01

    The biological effects of radiation result primarily from damage to DNA. There are three effects of concern to the radiologist that determine the need for radiation protection and the dose principle of ALARA (As Low As Reasonably Achievable). (1) Heritable effects. These were thought to be most important in the 1950s, but concern has declined in recent years. The current ICRP risk estimate is very small at 0.2%/Sv. (2) Effects on the developing embryo and fetus include weight retardation, congenital anomalies, microcephaly and mental retardation. During the sensitive period of 8 to 15 weeks of gestation, the risk estimate for mental retardation is very high at 40%/Sv, but because it is a deterministic effect, there is likely to be a threshold of about 200 mSv. (3) Carcinogenesis is considered to be the most important consequence of low doses of radiation, with a risk of fatal cancer of about 5%/Sv, and is therefore of most concern in radiology. Our knowledge of radiation carcinogenesis comes principally from the 60-year study of the A-bomb survivors. The use of radiation for diagnostic purposes has increased dramatically in recent years. The annual collective population dose has increased by 750% since 1980 to 930,000 person Sv. One of the principal reasons is the burgeoning use of CT scans. In 2006, more than 60 million CT scans were performed in the U.S., with about 6 million of them in children. As a rule of thumb, an abdominal CT scan in a 1-year-old child results in a life-time mortality risk of about one in a thousand. While the risk to the individual is small and acceptable when the scan is clinically justified, even a small risk when multiplied by an increasingly large number is likely to produce a significant public health concern. It is for this reason that every effort should be made to reduce the doses associated with procedures such as CT scans, particularly in children, in the spirit of ALARA. (orig.)

  5. Biological Effects of Ionizing Radiation

    International Nuclear Information System (INIS)

    Durand, J.L.

    2000-01-01

    The aim of this work is to verify the existence of the adaptive response phenomenon induced by low doses of ionizing radiation in living cells.A wild-type yeast Saccharomyces cerevisiae (Baker's yeast) was chosen as the biological target.As a parameter to quantify the sensibility of the target to radiation, the Lethal Dose 50 (LD50 ) was observed. In our experimental condition a value of (60 ± 1) Gy was measured for LD50 with Dose Rate of (0.44 ± 0.03) Gy/min. The method employed to show up the adaptive response phenomenon consisted in exposing the sample to low ''conditioning'' doses, which would initiate these mechanisms. Later the samples with and without conditioning were exposed to higher ''challenging'' doses (such as LD50), and the surviving fractions were compared. In order to maximize the differences, the doses and the time between irradiations were varied. The best results were obtained with both a conditioning dose of (0.44 ± 0.03) Gy and a waiting time of 2 hs until the application of the challenging dose. Following this procedures the 80% of the conditioned samples has survived, after receiving the application of the LD50. The adaptive response phenomenon was also verified for a wide range of challenging doses

  6. Optical Protection Filters for Harmful Laser Beams and UV Radiation

    Science.gov (United States)

    Azim M., Osama A.

    2007-02-01

    Due to the rapid growth of radiation protection applications in various devices and instruments, it is essential to use suitable filters for eye protection of the personal working in the radiation field. Different protection filters were produced to protect from four laser beam wavelengths (at 532nm, 632.8nm, 694nm and 1064nm) and block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters used optical thin film technology. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production filter processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Dralo (mixture of oxides TiO2/Al2O3), and Lima (mixture of oxides SiO2/Al2O3); deposition by an electron beam gun. The output transmittance curves for both theoretical and experimental values of all filters are presented. To validate the suitability for use in a `real world', rather than laboratory test application, full environmental assessment was also carried out. These filters exhibited high endurance after exposing them to the durability tests (adhesion, abrasion resistance and humidity) according to military standards MIL-C-675C and MIL-C-48497A.

  7. Optical Protection Filters for Harmful Laser Beams and UV Radiation

    International Nuclear Information System (INIS)

    Azim M, Osama A.

    2007-01-01

    Due to the rapid growth of radiation protection applications in various devices and instruments, it is essential to use suitable filters for eye protection of the personal working in the radiation field. Different protection filters were produced to protect from four laser beam wavelengths (at 532nm, 632.8nm, 694nm and 1064nm) and block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters used optical thin film technology. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production filter processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Dralo (mixture of oxides TiO2/Al2O3), and Lima (mixture of oxides SiO2/Al2O3); deposition by an electron beam gun. The output transmittance curves for both theoretical and experimental values of all filters are presented. To validate the suitability for use in a 'real world', rather than laboratory test application, full environmental assessment was also carried out. These filters exhibited high endurance after exposing them to the durability tests (adhesion, abrasion resistance and humidity) according to military standards MIL-C-675C and MIL-C-48497A

  8. Radioisotopes and ionizing radiations in biological research

    International Nuclear Information System (INIS)

    1984-01-01

    This book deals with the use of radioisotopes and ionizing radiations in the various aspects of biological research. The following topics were presented: labelled compounds; conformation-function relationships of hormonal polypeptides and their spectroscopic study; neutron scattering and neutron diffraction for biological studies; high resolution autoradiography; radioimmunoassay; nuclear medicine; transfer of excitation energy in photosynthesis; radioagronomy; radiation preservation of food [fr

  9. Biological effects of ionising radiation

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    The paper reports the proceedings of a conference organised jointly by Friends of the Earth (U.K.) and Greenpeace (International). The aim of the conference was to discuss the effects of low level radiation, particularly on man, within the terms of dose/risk relationships. The topics discussed included: sources of radiation, radiation discharges from nuclear establishments, predictive modelling of radiation hazards, radiation effects at Hiroshima, low dose effects and ICRP dose limits, variation in sensitivity to radiation, and the link between childhood cancer and nuclear power. (U.K.)

  10. Biological aspects of nuclear technology: nuclear technology potent medicine against malignancy care required to guard against harmful aspects

    International Nuclear Information System (INIS)

    Jain, V.K.

    2005-01-01

    Nuclear technology while producing energy is also used to produce Radioisotopes, so called artificial radioactivity. Radiations emitted by radioisotopes are very helpful in the diagnosis and treatment of malignant diseases. The subject of Radiation Biology developed with the need to study the effects of radiations on specific organs and areas of the human body. Along with the radioisotopes, instruments like Scanners, Cameras and Teletherapy machines were also developed to scan, map, deliver, and treat the specific parts of the body. A very large number of radioisotopes are now made, many of which are used for labeling compounds (radiopharmaceuticals) for targeting specific body organs in the sense that they tend to concentrate in those organs. Thus by scanning the organ, its condition is mapped or seen. This can then be treated by suitable amounts of the radioisotope delivered in a specific manner. Thus new disciplines of Nuclear Medicine and Medical Physics, developed as it became necessary to mark the cancerous area and calculate precisely the dose to be delivered and map its distribution. The other side of radioisotopes applications is their harmful effects on biological material which are also well known and well documented. Maximum limits of dose have been prescribed by National and International Organs to safeguard the health of the users. (author)

  11. Postgraduate studies in radiation biology in Europe

    International Nuclear Information System (INIS)

    Trott, K.R.; Lohmann, P.H.M.; Zeeland, A.A. van; Natarajan, A.T.; Schibilla, H.; Chadwick, K.; Kellerer, A.M.; Steinhaeusler, F.

    1998-01-01

    The present system of radiobiological research in universities and research centres is no longer able to train radiobiologists who have a comprehensive understanding of the entire field of radiation biology including both 'classical' and molecular radiation biology. However, such experts are needed in view of the role radiation protection plays in our societies. No single institution in Europe could now run a 1-year, full-time course which covers all aspects of the radiobiological basis of radiation protection. Therefore, a cooperative action of several universities from different EU member states has been developed and is described herein. (orig.)

  12. Biological effects of high LET radiations

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Masami [Nagasaki Univ. (Japan). Faculty of Pharmaceutical Sciences

    1997-03-01

    Biological effect of radiation is different by a kind of it greatly. Heavy ions were generally more effective in cell inactivation, chromosome aberration induction, mutation induction and neoplastic cell transformation induction than {gamma}-rays in SHE cells. (author)

  13. Radiation biology of medical imaging

    CERN Document Server

    Kelsey, Charles A; Sandoval, Daniel J; Chambers, Gregory D; Adolphi, Natalie L; Paffett, Kimberly S

    2014-01-01

    This book provides a thorough yet concise introduction to quantitative radiobiology and radiation physics, particularly the practical and medical application. Beginning with a discussion of the basic science of radiobiology, the book explains the fast processes that initiate damage in irradiated tissue and the kinetic patterns in which such damage is expressed at the cellular level. The final section is presented in a highly practical handbook style and offers application-based discussions in radiation oncology, fractionated radiotherapy, and protracted radiation among others. The text is also supplemented by a Web site.

  14. Roles of radiation chemistry in development and research of radiation biology

    International Nuclear Information System (INIS)

    Min Rui

    2009-01-01

    Radiation chemistry acts as a bridge connecting radiation physics with radiation biology in spatial and temporal insight. The theory, model, and methodology coming from radiation chemistry play an important role in the research and development of radiation biology. The chemical changes induced by ionizing radiation are involved not only in early event of biological effects caused by ionizing radiation but in function radiation biology, such as DNA damage and repair, sensitive modification, metabolism and function of active oxygen and so on. Following the research development of radiation biology, systems radiation biology, accurate quality and quantity of radiation biology effects need more methods and perfect tools from radiation chemistry. (authors)

  15. Biological radiation effects and radioprotection standards

    International Nuclear Information System (INIS)

    Clerc, H.

    1991-03-01

    In this report, after recalling the mode of action of ionizing radiations, the notions of dose, dose equivalents and the values of natural irradiation, the author describes the biological radiation effects. Then he presents the ICRP recommendations and their applications to the french radioprotection system

  16. Areas of research in radiation chemistry fundamental to radiation biology

    International Nuclear Information System (INIS)

    Powers, E.L.

    1980-01-01

    Among all the environmental hazards to which man is exposed, ionizing radiation is the most thoroughly investigated and the most responsibly monitored and controlled. Nevertheless, because of the importance of radiation in modern society from both the hazard as well as the utilitarian standpoints, much more information concerning the biological effects induced and their modification and reversal is required. Together with radiation physics, an understanding of radiation chemistry is necessary for full appreciation of biological effects of high and low energy radiations, and for the development of prophylactic, therapeutic and potentiating methods and techniques in biological organisms. The necessity of understanding the chemistry of any system, biological or not, that is to be manipulated and controlled, is so obvious as to make trivial a statement to that effect. If any natural phenomenon is to be put to our use, surely the elements of it must be studied and appreciated fully. In the preliminary statements of the various panels of this general group, the need for additional information on the basic radiation chemistry concerned in radiation-induced biological effects pervades throughout

  17. Biological effects of radiation and health risks from exposure to low levels of ionizing radiation

    International Nuclear Information System (INIS)

    Kotian, Rahul P.; Kotian, Sahana Rahul; Sukumar, Suresh

    2013-01-01

    The very fact that ionizing radiation produces biological effects is known from many years. The first case of injury reported by Sir Roentgen was reported just after a few months after discovery of X-rays in 1895. As early as 1902, the first case of X-ray induced cancer was reported in the literature. Early human evidence of harmful effects as a result of exposure to radiation in large amounts existed in the 1920s and 1930s, based upon the experience of early radiologists, miners exposed to airborne radioactivity underground, persons working in the radium industry, and other special occupational groups. The long-term biological significance of smaller, repeated doses of radiation, however, was not widely appreciated until relatively recently, and most of our knowledge of the biological effects of radiation has been accumulated since World War II. The mechanisms that lead to adverse health effects after exposure to ionizing radiation are still not fully understood. Ionizing radiation has sufficient energy to change the structure of molecules, including DNA, within the cells of the body. Some of these molecular changes are so complex that it may be difficult for the body's repair mechanisms to mend them correctly. However, the evidence is that only a small fraction of such changes would be expected to result in cancer or other health effects. The most thoroughly studied individuals for the evaluation of health effects of ionizing radiation are the survivors of the Hiroshima and Nagasaki atomic bombings, a large population that includes all ages and both sexes.The Radiation Effects Research Foundation (RERF) in Japan has conducted followup studies on these survivors for more than 50 years. An important finding from these studies is that the occurrence of solid cancers increases in proportion to radiation dose. More than 60% of exposed survivors received a dose of radiation of less than 100 mSv (the definition of low dose used by the BEIR VII report). (author)

  18. Biological effects of nuclear radiation

    International Nuclear Information System (INIS)

    Hotz, G.

    1975-01-01

    After a brief survey about the main radiobiological effects caused by ionizing radiation, human symptoms after irradiation and incorporation are shown. The special radiotoxic effect of radionuclides which are chemically associated with metabolism-specific elements such as calcium and potassium is shown and methods of treatment are indicated. (ORU) [de

  19. Sunscreens: topical and systemic approaches for protection of human skin against harmful effects of solar radiation

    International Nuclear Information System (INIS)

    Pathak, M.A.

    1982-01-01

    This review deals with topical and systemic approaches for protection of human skin against the harmful effects of solar radiation. Two concerns about the deleterious effects of sun exposure involve: (1) acute effects (e.g., sunburn and drug-induced phototoxicity) and (2) potential long-term risks of repeated sun exposures leading to development of solar elastosis, keratoses, induction of both nonmelanoma and melanoma skin cancer, and alteration of immune responses and functions. Action spectra of normal and abnormal reactions of human skin to acute and chronic effects of solar radiation are presented with a view to helping the physician prescribe the appropriate sunscreens. Factors that influence acute effects of sunburn are reviewed. Various artificial methods effective in minimizing or preventing harmful effects of solar radiation, both in normal individuals and in patients with photosensitivity-related problems, are discussed. Emphasis is placed on the commercially available chemical sunscreens and their properties. Sun protection factor (SPF) values of several brand-name formulations determined with a solar simulator under indoor conditions (laboratory) and with solar radiation under natural, field conditions are presented. Factors responsible for variations of SPF values observed under indoor and outdoor conditions are reviewed. Systemic photoprotective agents and their limitations are outlined. The photobiology of melanin pigmentation (the tanning reaction) is briefly discussed, with emphasis on the dangers of using quick-tanning lotions for stimulation of the tanning reaction

  20. Biological aspects of radiation carcinogenesis

    International Nuclear Information System (INIS)

    Upton, A.C.

    1984-01-01

    Ionizing radiation has been observed to increase the incidence of virtually every type of neoplasm, and carcinogenic effects have been noted in all species investigated. Susceptibility varies markedly, however, with species, strain, organ, cell type, sex, age at irradiation, physiological condition, exposure to other physical or chemical agents, and additional variables. Because of the multicausal, multistage nature of the cancer process, and the diversity of mechanisms through which carcinogenesis may be influenced by irradiation, the variety of observed dose-incidence relationships is not unexpected. The data are consistent with the concept that cancer arises from a single transformed cell, through a stepwise succession of undefined changes, and that the process of transformation may be initiated by radiation-induced damage to the DNA of the affected cell. There is also evidence that intercellular interactions may play an important role in the evolution of the neoplastic process, the nature and radiobiology of which remain to be determined

  1. Biological responses to ionizing radiation

    International Nuclear Information System (INIS)

    Hutchinson, T.C.; Harwell, M.A.; Cropper, W.P. Jr.; Grover, H.D.; Harwell, C.C.; Hacas, M.; Limburg, K.; Walton, D.W.H.; Worrest, R.C.

    1985-01-01

    Post-nuclear war local and global fall-out distribution and levels are discussed in relation to fission products and neutron activation radionuclides. Tables are presented of the sensitivities of the major ecosystems to ionising radiations, of the sensitivity of dormant seed, of small animals and birds, and of the main factors affecting plant sensitivity to radiation. Representative bioconcentration factors for Co, Cs and Sr for various species are listed, together with whole-body dose estimates to marine biota from 10,000 MT nuclear war. Internal doses, and pathways to humans are discussed. It is concluded that the direct effects of fallout on humans would far exceed the indirect effects resulting from destruction or disturbance of ecological systems. (UK)

  2. Biological consequences of radiation: risk factors

    International Nuclear Information System (INIS)

    1985-01-01

    This publication is a syllabus of a course on Radiation Protection. The publication offers an overview of the biological radiation effects at cellular level. For that purpose, different forms of cancers and their incidence are first discussed; structure and functioning of normal cells are considered and an introduction in genetics is given. Finally, an overview is presented of the character of tissue damage after high-dose irradiation. (G.J.P.)

  3. Synchrotron Radiation in Biology and Medicine

    International Nuclear Information System (INIS)

    Pelka, J.B.

    2008-01-01

    This work is focused on a present status of synchrotron radiation X-ray applications in medicine and biology to imaging, diagnostics, and radio- therapy. Properties of X-ray beams generated by synchrotron sources are compared with radiation produced by classical laboratory X-ray tubes. A list of operating and planned synchrotron facilities applicable to biomedical purposes is given, together with their basic characteristics. A concise overview of typical X-ray synchrotron techniques in biology and medicine is carried out with discussion of their specific properties and examples of typical results. (author)

  4. The influence of low doses of ionizing radiation on biological systems

    International Nuclear Information System (INIS)

    Kwiecinska, T.

    1986-11-01

    Recent results concerning possible beneficial effects of low doses of ionizing radiation on biological systems are summarized. It is also pointed out on the basis of existing evidence that harmful effects on living organisms take place not only in the case of excess but also in the case of deficiency of ionizing radiation. Possibility of using radio-enhanced ultralow luminescence for studying hormesis phenomena is discussed. 24 refs., 4 figs. (author)

  5. [Biological effects of non-ionizing electromagnetic radiation].

    Science.gov (United States)

    Fedorowski, A; Steciwko, A

    1998-01-01

    Since the mid 1970's, when Adey discovered that extremely-low-frequency electromagnetic field (ELF EMF) may affect the calcium ions efflux from various cells, bioeffects of non-ionizing radiation (NIR) have become the subject of growing interest and numerous research projects. At present, the fact that NIR exerts both stimulatory and inhibitory effects on different physiological cellular parameters is rather unquestionable. At the same time, some epidemiological studies suggest that exposure to EMF is potentially harmful even if its intensity is very low. It has been proved that thermal factors are not responsible for these effects, therefore nowadays, they are called 'non-thermal effects'. Our paper deals with three different aspects of biological effects of non-ionizing radiation, bioelectromagnetism, electromagnetobiology and electromagnetic bioinformation. Firstly, we describe how EMF and photons can be produced within a living cell, how biological cycles are controlled, and what are the features of endogenous electromagnetic radiation. Secondly, we discuss various facets of external EMF interactions with living matter, focusing on extremely-low-frequencies, radio- and microwaves. Possible mechanisms of these interactions are also mentioned. Finally, we present a short overview of current theories which explain how electromagnetic couplings may control an open and dissipative structure, namely the living organism. The theory of electromagnetic bioinformation seems to explain how different physiological processes are triggered and controlled, as well as how long-range interactions may possibly occur within the complex biological system. The review points out that the presented research data must be assessed very carefully since its evaluation is crucial to set the proper limits of EMF exposure, both occupational and environmental. The study of biological effects of non-ioinizing radiation may also contribute to the development of new diagnostic and therapeutic

  6. A Therapeutic Role for Survivin in Mitigating the Harmful Effects of Ionizing Radiation

    Directory of Open Access Journals (Sweden)

    Katherine H. Carruthers

    2016-01-01

    Full Text Available Background. Radiation therapy is a form of adjuvant care used in many oncological treatment protocols. However, nonmalignant neighboring tissues are harmed as a result of this treatment. Therefore, the goal of this study was to induce the production of survivin, an antiapoptotic protein, to determine if this protein could provide protection to noncancerous cells during radiation exposure. Methods. Using a murine model, a recombinant adenoassociated virus (rAAV was used to deliver survivin to the treatment group and yellow fluorescence protein (YFP to the control group. Both groups received targeted radiation. Visual inspection, gait analysis, and tissue histology were used to determine the extent of damage caused by the radiation. Results. The YFP group demonstrated ulceration of the irradiated area while the survivin treated mice exhibited only hair loss. Histology showed that the YFP treated mice experienced dermal thickening, as well as an increase in collagen that was not present in the survivin treated mice. Gait analysis demonstrated a difference between the two groups, with the YFP mice averaging a lower speed. Conclusions. The use of gene-modification to induce survivin expression in normal tissues allows for the protection of nontarget areas from the negative side effects normally associated with ionizing radiation.

  7. Radiation biology in Canada 1962-63

    International Nuclear Information System (INIS)

    Thacker, D.G.

    1963-02-01

    A survey of the research projects in radiation biology being carried out in Canada during the fiscal year 1962-63. The report includes the names of the investigators, their location, a brief description of the projects and information on the financial support being provided. A classification of the projects into areas of specific interest is also included. (author)

  8. Notions of radiation chemistry in biological systems

    International Nuclear Information System (INIS)

    Mastro, N.L. del.

    1989-10-01

    The present paper examines some aspects of the direct and indirect biological radiation effects: pair formation, free radicals, superoxide ion, hydrogen peroxide, hydroxyl radical, oxygen singlet together with the endogen radioprotector mechanisms of organisms and the ways in which an improved radioresistance of biochemical systems can be achieved. (author) [pt

  9. Breast cancer biology for the radiation oncologist

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Jonathan [Northwestern Univ., Chicago, IL (United States). Dept. of Radiation Oncology; Small, William [Loyola Univ. Chicago, Maywood, IL (United States). Stritch School of Medicine, Cardianl Bernardin Cancer Center; Woloschak, Gayle E. (ed.) [Northwestern Univ. Feinberg, Chicago, IL (United States). School of Medicine

    2015-10-01

    This is the first textbook of its kind devoted to describing the biological complexities of breast cancer in a way that is relevant to the radiation oncologist. Radiation Oncology has long treated breast cancer as a single biological entity, with all treatment decisions being based on clinical and pathologic risk factors. We are now beginning to understand that biological subtypes of breast cancer may have different risks of recurrence as well as different intrinsic sensitivity to radiotherapy. Multi-gene arrays that have for years been used to predict the risk of distant recurrence and the value of systemic chemotherapy may also have utility in predicting the risk of local recurrence. Additionally, the targeted agents used to treat breast cancer may interact with radiotherapy in ways that can be beneficial or undesirable. All of these emerging issues are extensively discussed in this book, and practical evidence-based treatment recommendations are presented whenever possible.

  10. Breast cancer biology for the radiation oncologist

    International Nuclear Information System (INIS)

    Strauss, Jonathan; Small, William; Woloschak, Gayle E.

    2015-01-01

    This is the first textbook of its kind devoted to describing the biological complexities of breast cancer in a way that is relevant to the radiation oncologist. Radiation Oncology has long treated breast cancer as a single biological entity, with all treatment decisions being based on clinical and pathologic risk factors. We are now beginning to understand that biological subtypes of breast cancer may have different risks of recurrence as well as different intrinsic sensitivity to radiotherapy. Multi-gene arrays that have for years been used to predict the risk of distant recurrence and the value of systemic chemotherapy may also have utility in predicting the risk of local recurrence. Additionally, the targeted agents used to treat breast cancer may interact with radiotherapy in ways that can be beneficial or undesirable. All of these emerging issues are extensively discussed in this book, and practical evidence-based treatment recommendations are presented whenever possible.

  11. Radon and radiation biology of the lung

    International Nuclear Information System (INIS)

    Crameri, R.; Burkart, W.

    1989-01-01

    The main papers presented at the meeting dealt with the behaviour of radon and the indoor environment, radiation biology of the lung, lung dosis and the possible cancer risk caused by radon in homes, contamination of the room air. A series of special papers treated the radon problem in detail: sources and transport mechanisms of radon, geological aspects of the radon radiation burden in Switzerland, radon in homes, search for radon sources, and the Swiss radon-programme RAPROS. 67 figs., 13 tabs., 75 refs

  12. Department of Radiation and Environmental Biology - overview

    International Nuclear Information System (INIS)

    Cebulska-Wasilewska, A.

    1994-01-01

    This year the Department of Radiation and Environmental Biology has been engaged in cytogenetic studies and continuation of our basic research into the genotoxic effects of ionizing and nonionizing radiation, chemicals mutagenic in the environment and their interaction with radiation. The relationship between the amount of energy deposited and the various types of damage that result from the exposure to fast neutrons and X-rays has been investigated. The second line of investigation - environmental studies has concentrated on the genotoxic effects of organic chemicals related to pesticides using the gene mutation in Tradescantia assay. The third line of research of Department is more linked to the possible improvement that might be achieved in clinical cancer therapy

  13. The molecular theory of radiation biology

    International Nuclear Information System (INIS)

    Chadwick, K.H.; Leenhouts, H.P.

    1981-01-01

    In this book we have tried to gather, in a logical sequence, the thoughts and reasoning which have led us from the raw and primitive beginning to the broader, more generally applicable, model. In doing this, it has been necessary to cover a wide range of topics in both cellular biology and radiation physics, and we apologize now to the reader who finds that we have gone into too much detail in one area and made too rough an approximation in the other. We have written what we feel is essential for the physicist to follow the influence exerted on the model by the biology, and for the biologist to follow the mathematical definition of the biological effect. (orig./VJ)

  14. Biological research for the radiation protection

    International Nuclear Information System (INIS)

    Kim, In Gyu; Kim, Chan Kug; Shim, Hae Won; Jung, Il Lae; Byun, Hee Sun; Moon, Myung Sook; Cho, Hye Jeong; Kim, Jin Sik

    2003-04-01

    The work scope of 'Biological Research for the Radiation Protection' had contained the research about polyamine effect on cell death triggered ionizing radiation, H 2 O 2 and toxic agents. In this paper, to elucidate the role of polyamines as mediator in lysosomal damage and stress(H 2 O 2 )- induced apoptosis, we utilized α-DiFluoroMethylOrnithine (DFMO), which inhibited ornithine decarboxylase and depleted intracellular putrescine, and investigated the effects of polyamine on the apoptosis caused by H 2 O 2 , ionizing radiation and paraquat. We also showed that MGBG, inhibitor of polyamine biosynthesis, treatment affected intracellular redox steady states, intracellular ROS levels and protein oxidation. Thereafter we also investigated whether MGBG may enhance the cytotoxic efficacy of tumor cells caused by ionizing radiation or H 2 O 2 because such compounds are able to potentiate the cell-killing effects. In addition, ceruloplasmin and thioredoxin, possible antioxidant proteins, were shown to have protective effect on radiation- or H 2 O 2 (or chemicals)-induced macromolecular damage or cell death

  15. Biological research for the radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Gyu; Kim, Chan Kug; Shim, Hae Won; Jung, Il Lae; Byun, Hee Sun; Moon, Myung Sook; Cho, Hye Jeong; Kim, Jin Sik

    2003-04-01

    The work scope of 'Biological Research for the Radiation Protection' had contained the research about polyamine effect on cell death triggered ionizing radiation, H{sub 2}O{sub 2} and toxic agents. In this paper, to elucidate the role of polyamines as mediator in lysosomal damage and stress(H{sub 2}O{sub 2})- induced apoptosis, we utilized {alpha}-DiFluoroMethylOrnithine (DFMO), which inhibited ornithine decarboxylase and depleted intracellular putrescine, and investigated the effects of polyamine on the apoptosis caused by H{sub 2}O{sub 2}, ionizing radiation and paraquat. We also showed that MGBG, inhibitor of polyamine biosynthesis, treatment affected intracellular redox steady states, intracellular ROS levels and protein oxidation. Thereafter we also investigated whether MGBG may enhance the cytotoxic efficacy of tumor cells caused by ionizing radiation or H{sub 2}O{sub 2} because such compounds are able to potentiate the cell-killing effects. In addition, ceruloplasmin and thioredoxin, possible antioxidant proteins, were shown to have protective effect on radiation- or H{sub 2}O{sub 2}(or chemicals)-induced macromolecular damage or cell death.

  16. Biological effects of low-dose ionizing radiation exposure

    International Nuclear Information System (INIS)

    Reinoehl-Kompa, Sabine; Baldauf, Daniela; Heller, Horst

    2009-01-01

    The report on the meeting of the Strahlenschutzkommission 2007 concerning biological effects of low-dose ionizing radiation exposure includes the following contributions: Adaptive response. The importance of DNA damage mechanisms for the biological efficiency of low-energy photons. Radiation effects in mammography: the relative biological radiation effects of low-energy photons. Radiation-induced cataracts. Carcinomas following prenatal radiation exposure. Intercellular apoptosis induction and low-dose irradiation: possible consequences for the oncogenesis control. Mechanistic models for the carcinogenesis with radiation-induced cell inactivation: application to all solid tumors in the Japanese atomic bomb survivors. Microarrays at low radiation doses. Mouse models for the analysis of biological effects of low-dose ionizing radiation. The bystander effect: observations, mechanisms and implications. Lung carcinoma risk of Majak workers - modeling of carcinogenesis and the bystander effect. Microbeam studies in radiation biology - an overview. Carcinogenesis models with radiation-induced genomic instability. Application to two epidemiological cohorts.

  17. Department of Radiation and Environmental Biology - Overview

    International Nuclear Information System (INIS)

    Cebulska-Wasilewska, A.

    2001-01-01

    Full text: In the year 2000 we completed our study of the genotoxic influence of occupational exposure to pesticides on human cells, and their susceptibility to radiation in particular. Examining blood samples from four countries: Greece, Hungary, Poland and Spain we found that exposure to pesticides usually resulted in an increased susceptibility to the UV-C radiation, although statistical significance could only be concluded for inhabitants of Poland. In Spain, exposure to pesticides was proved to impair the lymphocyte DNA repair capability, while for the Polish group this repair capability appeared enhanced in people exposed to pesticides (see the research reports below). The possible influence of lifestyle or particular diet on the observed national differences would probably be worth analyzing. We also investigate the biological effectiveness of therapeutic beams (neutrons and X-rays). Experimental part of such study, concerning neutrons of different mean energies, is over and the results are now being processed. Our work covers hot issues of environmental and radiation biology making us research partners to many domestic and foreign scientific institutions. Our proficiency in the field is also reflected by membership in various expert boards (e.g. evaluating research applications for the Fifth EU Framework Programme for RTD and Demonstration Activities in the field 'Environment and Health', lecturing in the 2000 NATO IOS Life Science Books). We have entered the 5 th EU Programme Scheme within the EXPAH project starting January 1, 2001. (author)

  18. Biological aspects of radiation in nuclear medicine

    International Nuclear Information System (INIS)

    Kotzerke, J.; Universitaetsklinikum Dresden; Forschungszentrum Dresden-Rossendorf e.V.; Oehme, L.; Forschungszentrum Dresden-Rossendorf e.V.

    2010-01-01

    Radiotherapy with unsealed radionuclides differs from external radiotherapy with regard to the radiation quality and energy range, the regional dose uniformity and the time course of irradiation regimen. External radiotherapy is planned precisely and can be applied to a target volume independently from blood flow during a course of irradiation fractions. In contrary, administered radiopharmaceuticals distribute according to their pharmacokinetic properties and generate a continuous irradiation corresponding to the effective halflife. The resulting dose rates are approximately 1 Gy/min and 1 Gy/h, respectively. The bio-kinetics of radiopharmaceuticals involves cellular accumulation and retention with highly variable affinity to specific organs that can be modulated as well. A remarkable dose gradient is found at the edge of volumes with enhanced uptake. The biological effect of an irradiation with decreasing intensity can be compared with the radiation effect caused by conventional fractionation with 2 Gy a day in external beam therapy by means of the linear-quadratic model. However, the experimental validation of this translation is still under investigation. Radionuclide therapy is usually performed in several cycles some month apart. This procedure fails to meet external radiotherapy. The vision of a combined external-internal radiotherapy requires efforts for a common dosimetry approach both in vitro and in vivo with a physical and biological verification of the results. (orig.)

  19. Department of Radiation and Environmental Biology - Overview

    International Nuclear Information System (INIS)

    Cebulska-Wasilewska, A.

    2000-01-01

    Full text:The year 1999 we devoted mainly to the activities concerning our basic research, and requirements and expectations of three research projects. The environmental project from the European Community was supporting our research in the issues of human monitoring of occupational exposure to pesticides. The two other radiobiology projects from the State Committee of Research were supporting our search on the biological efficiency and its enhancement of radio-therapeutic sources of various LET radiation. We succeeded fruitful co-operation with colleagues from Academy of Mining and Metallurgy that let us go faster with modernization of our laboratory by automation of our methods for screening cytogenetic damages. A lot of efforts were paid to modify our work by automatic reports of the coordinates of aberrant metaphases, and to make a smooth work of our new and own metaphase finder. We are sure that our new and unique research tool will not only enhance the accuracy and speed of measurements, but will also be useful for the purpose of the retrospective biological dosimetry of absorbed doses. We have applied fluorescent in situ hybridization (FISH) for cytogenetic studies of biological effects induced by neutrons. Now, we are looking forward to apply this technique in a combination with the DNA damage measures done by SCGE assay, to our research on mechanisms of the induction and repair, or interaction of the lesions induced by genotoxic agents. Understanding of the regulation of these processes could be a good goal for the new century to come. (author)

  20. Proceedings of the symposium on molecular biology and radiation protection

    International Nuclear Information System (INIS)

    Marko, A.M.

    1996-02-01

    The symposium on molecular biology and radiation protection was organized in sessions with the following titles: Radiation protection and the human genome; Molecular changes in DNA induced by radiation; Incidence of genetic changes - pre-existing, spontaneous and radiation-induced; Research directions and ethical implications. The ten papers in the symposium have been abstracted individually

  1. Ionizing radiation induced biological response and its public health implication

    International Nuclear Information System (INIS)

    Koeteles, Gy.

    1994-01-01

    Several sources of ionizing radiation exist in natural and artificial environment of humanity. An overview of their biological effects and the biological response of man is present. Emphasize is given to the differences caused by high and low doses. The interrelation of radiology, radiation hygiene and public health is pointed out. Especially, the physical and biological effects of radiation on cells and their responses are discussed in more detail. (R.P.)

  2. Biologically based multistage modeling of radiation effects

    Energy Technology Data Exchange (ETDEWEB)

    William Hazelton; Suresh Moolgavkar; E. Georg Luebeck

    2005-08-30

    This past year we have made substantial progress in modeling the contribution of homeostatic regulation to low-dose radiation effects and carcinogenesis. We have worked to refine and apply our multistage carcinogenesis models to explicitly incorporate cell cycle states, simple and complex damage, checkpoint delay, slow and fast repair, differentiation, and apoptosis to study the effects of low-dose ionizing radiation in mouse intestinal crypts, as well as in other tissues. We have one paper accepted for publication in ''Advances in Space Research'', and another manuscript in preparation describing this work. I also wrote a chapter describing our combined cell-cycle and multistage carcinogenesis model that will be published in a book on stochastic carcinogenesis models edited by Wei-Yuan Tan. In addition, we organized and held a workshop on ''Biologically Based Modeling of Human Health Effects of Low dose Ionizing Radiation'', July 28-29, 2005 at Fred Hutchinson Cancer Research Center in Seattle, Washington. We had over 20 participants, including Mary Helen Barcellos-Hoff as keynote speaker, talks by most of the low-dose modelers in the DOE low-dose program, experimentalists including Les Redpath (and Mary Helen), Noelle Metting from DOE, and Tony Brooks. It appears that homeostatic regulation may be central to understanding low-dose radiation phenomena. The primary effects of ionizing radiation (IR) are cell killing, delayed cell cycling, and induction of mutations. However, homeostatic regulation causes cells that are killed or damaged by IR to eventually be replaced. Cells with an initiating mutation may have a replacement advantage, leading to clonal expansion of these initiated cells. Thus we have focused particularly on modeling effects that disturb homeostatic regulation as early steps in the carcinogenic process. There are two primary considerations that support our focus on homeostatic regulation. First, a number of

  3. European Society for Radiation Biology 21. annual meeting

    International Nuclear Information System (INIS)

    1988-01-01

    The volume contains about 100 abstracts of lectures presented to the conference covering a large variety of topics like: Radiobiology as a base for radiotherapy, radiation carcinogenesis and cellular effects, late and secondary effects of radiotherapy, radioprotection and radiosensitization, heavy ions in radiobiology and space research, microdosimetry and biological dosimetry, radiation effects on the mature and the developing central nervous system, DNA damage and repair and cellular mutations, the imact of radiation on the environment, free radicals in radiation biology

  4. Activities in biological radiation research at the AGF

    International Nuclear Information System (INIS)

    1984-01-01

    The AGF is working on a wide spectrum of biological radiation research, with the different scientific disciplines contributing different methodologies to long-term research projects. The following fields are studied: 1. Molecular and cellular modes of action of radiation. 2. Detection and characterisation of biological radiation damage, especially in humans. 3. Medical applications of radiation effects. 4. Concepts and methods of radiation protection. The studies will lead to suggestions for radiation protection and improved radiotherapy. They may also contribute to the development of environmental protection strategies. (orig./MG) [de

  5. Applications of synchrotron radiation in biology and medicine

    International Nuclear Information System (INIS)

    Khole, V.

    1988-01-01

    This paper discusses the important role of synchrotron radiation in dealing with problems in various branches of biology and medicine, viz. molecular biology, molecular biophysics, biochemistry, cell biology, X-ray microscopy, molecular surgery, medical diagnostics (angiography, X-ray radiography, forensic medicine, element analysis), environmental biology, pollution control and photobiology. (author). 15 refs., 9 figs

  6. Topical Day on Biological Effects of Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Baatout, S.; Jacquet, P.

    1997-05-15

    The topical day has been focussed on the potential effects of ionizing radiation on human health. A general overview on molecular and biophysical aspects of radiation, its effects on cells and organisms, and the contribution of radiobiology to radiation protection and risk assessment is given. The genetic effects of radiation and its effects on the developing organism, the effects of radiation on the cell cycle and the mechanisms of radiation induced apoptosis were also discussed.

  7. Topical Day on Biological Effects of Radiation

    International Nuclear Information System (INIS)

    Baatout, S.; Jacquet, P.

    1997-01-01

    The topical day has been focussed on the potential effects of ionizing radiation on human health. A general overview on molecular and biophysical aspects of radiation, its effects on cells and organisms, and the contribution of radiobiology to radiation protection and risk assessment is given. The genetic effects of radiation and its effects on the developing organism, the effects of radiation on the cell cycle and the mechanisms of radiation induced apoptosis were also discussed

  8. The progress of molecular biology in radiation research

    International Nuclear Information System (INIS)

    Wei Kang

    1989-01-01

    The recent progress in application of molecular biology techniques in the study of radiation biology is reviewed. The three sections are as follows: (1) the study of DNA damage on molecular level, (2) the molecular mechanism of radiation cell genetics, including chromosome abberation and cell mutation, (3) the study on DNA repair gene with DNA mediated gene transfer techniques

  9. Biological Effects of Space Radiation and Development of Effective Countermeasures

    OpenAIRE

    Kennedy, Ann R.

    2014-01-01

    As part of a program to assess the adverse biological effects expected from astronaut exposure to space radiation, numerous different biological effects relating to astronaut health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death an...

  10. Outcome of radiation biology in radiotherapy. Past and future directions

    International Nuclear Information System (INIS)

    Hennequin, C.; Favaudon, V.

    2000-01-01

    Over the last ten years the impact of fundamental radiation biology into daily radiotherapy has been of concern chiefly to fractionation, prediction of radiation response, tumour oxygenation, intrinsic radiosensitivity including genetic approaches, and the determinants of the outcome of chemoradiotherapy combinations. Future goals will rely on sophisticated approaches, based on the progress of molecular and cellular biology and the characterization of new targets for radiation. Some of these novel advances will be discussed. (authors)

  11. Department of Radiation and Environmental Biology - Overview

    International Nuclear Information System (INIS)

    Cebulska-Wasilewska, A.

    2002-01-01

    Full text: The year 2001 started for us with new demanding tasks connected with participation in a new research project performed in collaboration with a excellent teams from six countries under the 5 th EU the Quality of Life Programme. The aim of the project EXPAH is to propose methods of molecular epidemiology for the risk assessment of exposure to polycyclic aromatic hydrocarbons in the air. The exploration of cause-effect relationships for carcinogenic agents will be based on the study of exogenous and endogenous influence on DNA damage in exposed population, and will determine the relationship between biomarkers of exposure, effects and susceptibility in the exposed populations. Analysis of this damage is carried out using highly specialising multidisciplinary techniques brought together by seven laboratories specialised in chemical, biochemical and biological techniques for analysing DNA damage and repair, together with access to populations exposed to environmental pollution and experience in collecting samples. In the year 2001 all the members of the department put much effort in co-organizing 12. Meeting of the Maria Sklodowska-Curie Polish Radiation Research Society. The Meeting was held in the September in Cracow and rewarded hard work of everybody with many applauding comments for the high scientific and organization level. Our parallel activities were concentrated on arrangement and preparation of the forthcoming Course on Human Monitoring for Genetic Effects proposed to us by the Alexander Hollaender Committee of the International Environmental Mutagenesis Society. The Alexander Hollaender ''HUMOGEF'' Course will concentrate on the commonly measured biomarkers (chromosome aberrations; micronuclei; DNA damage), but others (p53 protein levels; metabolic genotypes) will also be addressed. Scientists of international standing from the fields of toxicology, molecular biology, cytogenetics, mutation, and epidemiology, will present and discuss the state

  12. A Paradigm Shift in Low Dose Radiation Biology

    Directory of Open Access Journals (Sweden)

    Z. Alatas

    2015-08-01

    Full Text Available When ionizing radiation traverses biological material, some energy depositions occur and ionize directly deoxyribonucleic acid (DNA molecules, the critical target. A classical paradigm in radiobiology is that the deposition of energy in the cell nucleus and the resulting damage to DNA are responsible for the detrimental biological effects of radiation. It is presumed that no radiation effect would be expected in cells that receive no direct radiation exposure through nucleus. The risks of exposure to low dose ionizing radiation are estimated by extrapolating from data obtained after exposure to high dose radiation. However, the validity of using this dose-response model is controversial because evidence accumulated over the past decade has indicated that living organisms, including humans, respond differently to low dose radiation than they do to high dose radiation. Moreover, recent experimental evidences from many laboratories reveal the fact that radiation effects also occur in cells that were not exposed to radiation and in the progeny of irradiated cells at delayed times after radiation exposure where cells do not encounter direct DNA damage. Recently, the classical paradigm in radiobiology has been shifted from the nucleus, specifically the DNA, as the principal target for the biological effects of radiation to cells. The universality of target theory has been challenged by phenomena of radiation-induced genomic instability, bystander effect and adaptive response. The new radiation biology paradigm would cover both targeted and non-targeted effects of ionizing radiation. The mechanisms underlying these responses involve biochemical/molecular signals that respond to targeted and non-targeted events. These results brought in understanding that the biological response to low dose radiation at tissue or organism level is a complex process of integrated response of cellular targets as well as extra-cellular factors. Biological understanding of

  13. Human · mouse genome analysis and radiation biology. Proceedings

    International Nuclear Information System (INIS)

    Hori, Tada-aki

    1994-03-01

    This issue is the collection of the papers presented at the 25th NIRS symposium on Human, Mouse Genome Analysis and Radiation Biology. The 14 of the presented papers are indexed individually. (J.P.N.)

  14. AINSE conference on radiation biology and chemistry. Conference handbook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The conference handbook contains 60 oral and poster presentations dealing with recent advances in radiation chemistry applied to biological studies, radiopharmaceuticals, radiosensitizers as well as to solid state chemical physics.

  15. Role of cytogenetic techniques in biological dosimetry of absorbed radiation

    International Nuclear Information System (INIS)

    Rao, B.S.

    2016-01-01

    In most of the radiation accidents, physical dosimetric information is rarely available. Further, most of the accidental exposures are non-uniform involving either partial body or localized exposure to significant doses. In such situations, physical dosimetry does not provide reliable dose estimate. It has now been realized that biological dosimetric techniques can play an important role in the assessment of absorbed dose. In recent years, a number of biological indicators of radiation have been identified. These include the kinetics of onset and persistence of prodromal syndromes (radiation sickness), cytogenetic changes in peripheral blood lymphocytes, hematological changes, biochemical indicators, ESR spectroscopy of biological samples, induction of gene mutations in red blood cells, cytogenetic and physiological changes in skin and neurophysiological changes. In general, dosimetric information is derived by a combination of several different methods, as they have potential to serve as prognostic indicators. The role of cytogenetic techniques in peripheral blood lymphocytes (PBL) as biological indicators of absorbed radiation is reviewed here

  16. AINSE conference on radiation biology and chemistry. Conference handbook

    International Nuclear Information System (INIS)

    1994-01-01

    The conference handbook contains 60 oral and poster presentations dealing with recent advances in radiation chemistry applied to biological studies, radiopharmaceuticals, radiosensitizers as well as to solid state chemical physics

  17. Current research in Canada on biological effects of ionizing radiation

    International Nuclear Information System (INIS)

    Marko, A.M.

    1980-05-01

    A survey of current research in Canada on the biological effects of ionizing radiation has been compiled. The list of projects has been classified according to structure (organizational state of the test system) as well as according to the type of effects. Using several assumptions, ballpark estimates of expenditures on these activities have been made. Agencies funding these research activities have been tabulated and the break-down of research in government laboratories and in academic institutions has been designated. Wherever possible, comparisons have been made outlining differences or similarities that exist between the United States and Canada concerning biological radiation research. It has been concluded that relevant research in this area in Canada is inadequate. Wherever possible, strengths and weaknesses in radiation biology programs have been indicated. The most promising course for Canada to follow is to support adequately fundamental studies of the biological effects of radiation. (auth)

  18. The use of nuclear reactor in radiation biology

    International Nuclear Information System (INIS)

    Ujeno, Yowri

    1991-01-01

    The Kyoto University Reactor (KUR) is widely used not only in biology, but also in applied biology, today. These studies were surveyed in the present paper and the future possibility to use KUR in radiation biology was discussed. The researches on the effects of thermal neutrons on various normal tissues, the biological effects of neutrons except thermal neutrons, especially intermediate neutrons between thermal and high speed neutrons or cold neutrons, the adaptive response of cells to thermal neutron radiation, the application of nuclear reactor-produced radionuclides including 195m Pt to biology, and the mutation in botanical science and so on, should be continued using nuclear reactor. The necessity of nuclear reactor in biology and applied biology is emphasized. (author)

  19. Acute Radiation Syndrome (ARS) and its harmful effects on human health

    International Nuclear Information System (INIS)

    Khanam, Yasmin; Singh, Yogender

    2012-01-01

    After radiation exposure a series of many clinical syndromes appear that is called as Acute Radiation Syndrome (ARS). ARS also known as radiation toxicology or radiation sickness. Both low and higher doses radiation exposure on human body cause different types of radiation syndromes. These radiations may be ionizing radiations. X-rays and gamma rays etc. some times neutrons or radionuclides may also be deposited in human body and their effective doses cause major injuries or abnormalities even sometimes death also. ARS consist of a sequence of phased symptoms. These symptoms appear after the radiation exposure for several days to several months or sometimes for a long period or years. ARS depends on the quantity of absorbed radiation dose (rad0). ARS is characterized by an initial prodromal stage of malaise, nausea, vomiting, and diarrhea. Critical effects of ARS are Hematologic, that results infections to low white blood cells (WBC), bleeding due to low platelets and anemia due to low red blood cells (RBC), Gastrointestinal results nausea, vomiting, loss of appetite and abdominal pain (exposure doses of 600-1000 rad) and Neurovascular depending on the exposure dose. Neurovascular syndrome typically occurs at exposure doses greater than 1000 rad. It presents with neurological symptoms such as dizziness, headache, or decreased level of consciousness with an absence of vomiting. The clinical course of radiation sickness following a single intensive exposure to whole body radiation is characterized by three successive phases; a prodromal phase, which develops within minutes or hours after exposure, an ensuring latent period, which is relatively asymptomatic; and the main phase of the illness. Complete Blood Count (CBC) are helpful for the diagnosis for ARS. ARS may cause skin damage or loss of epidermis. Person suffering from nausea, vomiting, diarrhea should be admitted to well equipped hospitals or clinics. High exposured persons should be analysed CBC. Their

  20. Biological effect of radiation on human

    International Nuclear Information System (INIS)

    Lee, Yun Sil; Cho, Chul Koo; Lee, Su Jae

    2000-04-01

    1. Adaptive response when 0.01 Gy was preirradiated before high challenging dose is induced in normal cell types such normal lymphocytes, primary keratinocytes, and L929 fibroblast cells but not in neoplastic cells such as L5178Y lymphoma cells, EL-4 lymphoma cells and 308 papilloma cells. 2. Heat shock protein (HSP) 25 and inducible HSP70 is responsible for the induction of adaptive response and radioresistance - cell cycle regulation, antiapoptotic molecule and PKC activation were involved. 3. Apoptosis was induced at most 5. hrs after irradiation in primary keratinocytes, in v-rasHa transformed keratinocytes, the maximum interval was 16 hrs, and in 308 papilloma cells, the maximum was 48 hrs. 4. PKC response by radiation is correlated with induction of apoptosis. 5. Rapid induction PKCdelta in primary keratinocytes and no response of PKC epsilon may involved in radiation induced apoptosis. 6. The rate of resorption was increased when radiation was given at 2.5 days after gestation. Early death including foetal death were highly expressed when radiation was given at 7.5 days after gestation. There are no difference in incidence of late death including embryonic death. 7. 2 Gy is the most effective dose in radiation induced teratogenesis in mouse model. 8. Growth retardation and small head was present when radiation was given at 5.5, 7.5, 11.5 and 15.5 days after gestation and small head showed high incidence at 11.5 days after gestation. 9. External malformation, internal malformation and skeletal malformation was induced when radiation was given at 7.5 days after gestation. 10. OGG1-mutated cells induced radiosensitive by G2/M cell cycle arrest. 11. Radiation induced G2/M phase cell cycle and correlated with radiosensitivity. 12. PKCalpha induced differentiation. 13. Radiation exposed cells showed carcinogenic effect. 14. Organ specific radiosensitivity was shown and protein expression was involved

  1. Biological effect of radiation on human

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yun Sil; Cho, Chul Koo; Lee, Su Jae [and others

    2000-04-01

    1. Adaptive response when 0.01 Gy was preirradiated before high challenging dose is induced in normal cell types such normal lymphocytes, primary keratinocytes, and L929 fibroblast cells but not in neoplastic cells such as L5178Y lymphoma cells, EL-4 lymphoma cells and 308 papilloma cells. 2. Heat shock protein (HSP) 25 and inducible HSP70 is responsible for the induction of adaptive response and radioresistance - cell cycle regulation, antiapoptotic molecule and PKC activation were involved. 3. Apoptosis was induced at most 5. hrs after irradiation in primary keratinocytes, in v-rasHa transformed keratinocytes, the maximum interval was 16 hrs, and in 308 papilloma cells, the maximum was 48 hrs. 4. PKC response by radiation is correlated with induction of apoptosis. 5. Rapid induction PKCdelta in primary keratinocytes and no response of PKC epsilon may involved in radiation induced apoptosis. 6. The rate of resorption was increased when radiation was given at 2.5 days after gestation. Early death including foetal death were highly expressed when radiation was given at 7.5 days after gestation. There are no difference in incidence of late death including embryonic death. 7. 2 Gy is the most effective dose in radiation induced teratogenesis in mouse model. 8. Growth retardation and small head was present when radiation was given at 5.5, 7.5, 11.5 and 15.5 days after gestation and small head showed high incidence at 11.5 days after gestation. 9. External malformation, internal malformation and skeletal malformation was induced when radiation was given at 7.5 days after gestation. 10. OGG1-mutated cells induced radiosensitive by G2/M cell cycle arrest. 11. Radiation induced G2/M phase cell cycle and correlated with radiosensitivity. 12. PKCalpha induced differentiation. 13. Radiation exposed cells showed carcinogenic effect. 14. Organ specific radiosensitivity was shown and protein expression was involved.

  2. Cells, targets, and molecules in radiation biology

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1979-01-01

    Cellular damage and repair are discussed with regard to inactivation models, dose-effect curves and cancer research, repair relative to damage accumulation, potentially lethal damage, repair of potentially lethal vs. sublethal damage, cell killing and DNA damage due to nonionizing radiation, and anisotonicity vs. lethality due to nonionizing radiation. Other topics discussed are DNA damage and repair in cells exposed to ionizing radiation, kinetics of repair of single-strand DNA breaks, effects of actinomycin D on x-ray survival curve of hamster cells, misrepair and lethality, and perspective and prospects

  3. Current research in Radiation Biology and Biochemistry Division

    International Nuclear Information System (INIS)

    Tarachand, U.; Singh, B.B.

    1995-01-01

    The Radiation Biology and Biochemistry Division, Bhabha Atomic Research Centre, Bombay has been engaged in research in the frontier areas of (i) radiation biology related to tumour therapy and injury caused by free radicals; (ii) molecular basis of diseases of physiological origin; (iii) molecular aspects of chemical carcinogenesis and (iv) structure of genome and genome related functions. The gist of research and development activities carried out in the Division during the last two years are documented

  4. European activities in space radiation biology and exobiology

    International Nuclear Information System (INIS)

    Horneck, G.

    1996-01-01

    In view of the space station era, the European Space Agency has initiated a review and planning document for space life sciences. Radiation biology includes dosimetry of the radiation field and its modification by mass shielding, studies on the biological responses to radiation in space, on the potential impact of space flight environment on radiation effects, and assessing the radiation risks and establishing radiation protection guidelines. To reach a better understanding of the processes leading to the origin, evolution and distribution of life, exobiological activities include the exploration of the solar system, the collection and analysis of extraterrestrial samples and the utilization of space as a tool for testing the impact of space environment on organics and resistant life forms. (author)

  5. Biophysical interpretation on the biological actions of radiations

    International Nuclear Information System (INIS)

    Nishiwaki, Yasushi

    1960-01-01

    It is known that nuclear radiations such as alpha, beta, gamma, x-rays and neutron, proton and other heavy ion beams have many different actions on living cells; as killing, delaying growth, abnormal cell divisions and various genetical mutations and chromosomal aberrations. This document describes the mechanisms and kinetics of biological effects of ionizing radiation

  6. Biological effects and hazards of radiation exposure

    International Nuclear Information System (INIS)

    Boas, J.F.; Solomon, S.B.

    1990-01-01

    Radiation induced carcinogenesis and mutagenesis form the main risk to health from exposure to low levels of radiation. This risk effects can be at least qualitatively understood by considering the effects of radiation on cell DNA. Whilst exposure to high levels of radiation results in a number of identifiable effects, exposure to low levels of radiation may result in effects which only manifest themselves after many years. Risk estimates for low levels of radiation have been derived on the basis of a number of assumptions. In the case of uranium mine workers a major hazard arises from the inhalation of radon daughters. Whilst the correlation between radon daughter exposure and lung cancer incidence is well established, the numerical value of the risk factor is the subject of controversy. ICRP 50 gives a value of 10 cases per 10 6 person-years at risk per WLM (range 5-15 x 10 -6 PYR -1 WLM -1 ). The effect of smoking on lung cancer incidence rates amongst miners is also controversial. Nevertheless, smoking by miners should be discouraged

  7. A contribution to the knowledge of biology and harmfulness of Deporaus betulae (L. (Coleoptera, Attelabidae

    Directory of Open Access Journals (Sweden)

    Jaroslav Urban

    2012-01-01

    Full Text Available The paper deals with the occurrence, development and harmfulness of Deporaus betulae (L.. The majority of field studies was carried out at Training Forest Enterprise (TFE Masaryk Forest in Křtiny (District Brno-venkov in 2010 and 2011. In addition to this, the species was studied in detail also in a laboratory. It occurred mostly on Betula pendula and Carpinus betulus. Rarely, the species was found on Alnus glutinosa and Corylus avellana and only sporadically on Fagus sylvatica, Quercus petraea, Tilia cordata and T. platyphyllos. In the studied area, larvae and pupae hibernate. Beetles occur on trees from the end of April to the beginning of July, sporadically later. Females lay on average 2.5 (in the laboratory 4.4 eggs into rolls on B. pendula, on C. betulus 2.2 eggs. During two months, they damage on average 5.3 cm2 leaves creating 14 rolls and laying 35 eggs into the rolls. Larvae consume only 1.7 cm2 leaf blade. The development of the species takes three to four months from egg laying to the departure of larvae into soil. On leaves of B. pendula of an average area of 14.2 cm2, females roll up the same area (about 11.2 cm2 as on leaves of C. betulus of an area of 21.7 cm2. Into the rolls, they lay on average the same number of eggs. The average number of eggs in rolls increases with the increased area of B. pendula leaf blade. Trees partly compensate for the reduction of assimilatory area also by the growth of the area of neighbouring undamaged leaves (on average by 12.7 %.

  8. Gene Expression Profiling of Biological Pathway Alterations by Radiation Exposure

    Directory of Open Access Journals (Sweden)

    Kuei-Fang Lee

    2014-01-01

    Full Text Available Though damage caused by radiation has been the focus of rigorous research, the mechanisms through which radiation exerts harmful effects on cells are complex and not well-understood. In particular, the influence of low dose radiation exposure on the regulation of genes and pathways remains unclear. In an attempt to investigate the molecular alterations induced by varying doses of radiation, a genome-wide expression analysis was conducted. Peripheral blood mononuclear cells were collected from five participants and each sample was subjected to 0.5 Gy, 1 Gy, 2.5 Gy, and 5 Gy of cobalt 60 radiation, followed by array-based expression profiling. Gene set enrichment analysis indicated that the immune system and cancer development pathways appeared to be the major affected targets by radiation exposure. Therefore, 1 Gy radioactive exposure seemed to be a critical threshold dosage. In fact, after 1 Gy radiation exposure, expression levels of several genes including FADD, TNFRSF10B, TNFRSF8, TNFRSF10A, TNFSF10, TNFSF8, CASP1, and CASP4 that are associated with carcinogenesis and metabolic disorders showed significant alterations. Our results suggest that exposure to low-dose radiation may elicit changes in metabolic and immune pathways, potentially increasing the risk of immune dysfunctions and metabolic disorders.

  9. Biological Bases for Radiation Adaptive Responses in the Lung

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Bobby R. [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Lin, Yong [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Wilder, Julie [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Belinsky, Steven [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States)

    2015-03-01

    Our main research objective was to determine the biological bases for low-dose, radiation-induced adaptive responses in the lung, and use the knowledge gained to produce an improved risk model for radiation-induced lung cancer that accounts for activated natural protection, genetic influences, and the role of epigenetic regulation (epiregulation). Currently, low-dose radiation risk assessment is based on the linear-no-threshold hypothesis, which now is known to be unsupported by a large volume of data.

  10. Biological effects of the ionizing radiation. Press breakfast

    International Nuclear Information System (INIS)

    Flury-Herard, A.; Boiteux, S.; Dutrillaux, B.; Toledano, M.

    2000-06-01

    This document brings together the subjects discussed during the Press breakfast of 29 june 2000 on the biological effects of the ionizing radiations, with scientists of the CEA and the CNRS. It presents the research programs and provides inquiries on the NDA operating to introduce the NDA damages by ionizing radiations, the possible repairs and the repair efficiency facing the carcinogenesis. Those researches allow the scientists to define laws on radiation protection. (A.L.B.)

  11. Biological effects of ionizing radiation - changing worker attitudes

    International Nuclear Information System (INIS)

    Johnson, N.; Schenley, C.

    1989-01-01

    Training Resources and Data Exchange (TRADE) Radiation Protection Training Special Interest Group has taken an innovative approach to providing DOE contractors with radiation worker training material information. Newly-hired radiation workers may be afraid to work near radiation and long-term radiation workers may become indifferent to the biological hazard of radiation. Commercially available training material is often presented at an inappropriate technical level or in an uninteresting style. These training problems have been addressed in the DOE system through development of a training videotape and supporting material package entitled Understanding Ionizing Radiation and its Biological Effects. The training package, developed and distributed by TRADE specifically to meet the needs of DOE contractor facilities, contains the videotape and accompanying paper supporting materials designed to assist the instructor. Learning objectives, presentation suggestion for the instructor, trainee worksheets, guided discussion questions, and trainee self-evaluation sheets are included in the training package. DOE contractors have agreed that incorporating this training module into radiation worker training programs enhances the quality of the training and increase worker understanding of the biological effects of ionizing radiation

  12. Research in radiation biology, in the environment, and in radiation protection at CRNL

    International Nuclear Information System (INIS)

    Marko, A.M.; Myers, D.K.; Ophel, I.L.; Cowper, G.; Newcombe, H.B.

    1978-01-01

    Research in radiation biology at CRNL is concerned with: evaluation of the effects of low doses of radiation upon humans and other living organisms; the development of new methods for detecting the effects of radiation exposure in large populations; the continued development of improved methods by which radiation levels can be measured accurately and reliably; and evaluation of the effects of nuclear power use upon the environment. The present report summarizes our background knowledge of radiation hazards and describes current research activities in Biology and Health Physics Division at CRNL. (author)

  13. Do Good Without Causing Undue Harm. Experts Tackle Patient Radiation Safety During IAEA's Scientific Forum

    International Nuclear Information System (INIS)

    Henriques, Sasha

    2011-01-01

    Worldwide, about four billion X-ray exams, 35 million nuclear medicine exams and eight million radiation therapy treatment courses are undertaken each year. With millions exposed to ionizing radiation for medical purposes, and developing countries acquiring more machines to treat and diagnose cancer, the safety of patients is an ever-increasing concern. During the IAEA´s Scientific Forum, cancer experts and regulators put their heads together to explore the problems and possible solutions relating to the safe and appropriate use of new radiation medicine technology in developed and developing countries

  14. Biological effects of radiation human health and safety

    International Nuclear Information System (INIS)

    1977-05-01

    The biological hazards of nuclear energy usage are a growing source of public concern. The medical profession may well be expected to contribute to public debate on the issue. This document, therefore, attempts a balanced review of the known and suspected human biological consequences of exposure to different types of ionizing radiation, emphasizing in particular the nuclear industry

  15. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1993--November 30, 1994

    International Nuclear Information System (INIS)

    Hall, E.J.; Zaider, M.

    1994-05-01

    Research at the Center for Radiological Research is a blend of physics, chemistry and biology and epitomizes the multidisciplinary approach towards understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. To an increasing extent, the focus of attention is on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights from the past year are briefly described

  16. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1993--November 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1994-05-01

    Research at the Center for Radiological Research is a blend of physics, chemistry and biology and epitomizes the multidisciplinary approach towards understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. To an increasing extent, the focus of attention is on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights from the past year are briefly described.

  17. MEDICAL ASPECTS AND HARMFUL EFFECTS OF 50HZ ELECTROMAGNETIC FILED ON BIOLOGICAL SISTEMS

    Directory of Open Access Journals (Sweden)

    Dušan Sokolović

    2003-10-01

    Full Text Available Exposure to electromagnetic field (EMF with extremely low frequency (ELF of 50Hz is very frequent nowadays. All frequency range of these fields are called electromagnetic smog.The aim of this experimental investigation was determination of ELF EMP influence on animals behavior, reproductive ability and oxidative stress as possible biological marker for EMP exposition.Wistar rats 4 months old were divided in experimental (4 female and 6 male animal and control group (4 female and 5 male. The experimental group was 45 days exposed to an electromagnetic field frequency 50 Hz, magnetic induction B=48 mT and intensity of electric field of E=50 V/m. Fertility is measured by number of newborn and biological effects were determined by observation of individual and collective behavior. Determination of increased oxidative stress was measured by quantity of malondialdehyde in brain homogenate.Aggresive behavior and visible panic reaction, disorientation and anxiosity were registered in experimental group. Increased oxydative stress was measured by significantly higher concentration of malondialdehyde in brain homogenate of experimental animals (4,89±0,65 nmol/mg prot. vs. control 2,72±0,42 nmol/mg prot., p<0.01. Impaired fertility was manifested through unsuccessful pregnancy of experimental animals. Exposition to ELF EMF induces disorders of central nervous sistem functions, increasing oxydative stress and impaired reproductive functions.

  18. Request for Travel Funds for Systems Radiation Biology Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos-Hoff, Mary Helen [NYU School of Medicine

    2014-03-22

    The 3rd International Systems Radiation Biology Workshop brought together the major European, US and Japanese research programs on radiation risk as well as selected experts representing systems biological approaches to discuss how the new methodologies could be best exploited for low dose research. A significant part of the workshop was devoted to discussions organised as breakout group sessions. To facilitate discussions number of participants was limited to 60 persons. To achieve the goals of this symposium in this international conference, support from DOE is vital. Hence, this proposal requested support in the amount of $15,000 to cover the travel expenses of international experts and radiation biology scientists from the United States. This supporting mechanism was clearly identified to the selected US participants as a conference support award from the DOE (See attached PDF). The workshop was an outstanding opportunity to strengthen interactions between leading experts in the emerging areas of radiation sciences, and will also provide opportunities for younger scientists to meet with experts and discuss their results. This workshop was designed to endorse active engagement in international collaboration. A major objective of this conference was to effectively communicate research results, in order to ensure that current thinking reflects sound science of radiation biology. Further, this international event addressed the use and success of scientific initiatives in radiation biology for policymakers, standard-setters, and the general public.

  19. Concentration of biological molecules with radiation crosslinked hydrogels

    International Nuclear Information System (INIS)

    Acharya, Anjali; Sabharwal, S.

    2001-01-01

    Radiation crosslinked temperature sensitive Poly(N-isopropylacrylamide) hydrogels have been synthesised and utilised to concentrate biological molecules from dilute aqueous solutions. Both gamma radiation and electron beam radiation technique have been used to form crosslinked hydrogels. The solutes used for this study include biological macromolecules of varying molecular weights such as bovine serum albumin, chicken egg albumin, lysozyme and a-amylase. The effect of synthesis conditions of hydrogel namely radiation dose, solute concentration and pH of solution on the exclusion efficiencies of hydrogels have been investigated for these macromolecules. The reversible volume phase transition of the gels at 34 degC has been exploited for regeneration of the gels. The results show that biological macromolecules with M w > 40000 call be suitably concentrated using such hydrogels

  20. Radiation biology as a basis for multidisciplinary cancer therapy

    International Nuclear Information System (INIS)

    Hosoya, N.

    2017-01-01

    The research field of radiation biology has progressed greatly thanks to the advances in molecular biology. DNA in the cell nucleus is the principal target of radiation. The biological effect of radiation can be determined by how the DNA damage is processed in the cell. In order to prevent deleterious biological effects due to DNA damage, the cells possess a system termed 'DNA damage response'. The DNA damage response finally induces cell cycle arrest, activation of DNA repair pathways, or cell death. If accurately repaired, DNA damage will result in survival of cells with no biological effects. If inaccurately repaired, DNA damage may result in survival of cells exhibiting genetic alterations, which can lead to the development of various diseases including cancer. If unrepaired, fatal DNA damage such as the DNA double-strand break will result in cell depth. Since radiation therapy and chemotherapy are designed to specifically kill cancer cells by inducing DNA double-strand breaks, it is important to take advantage of cancer-specific abnormalities in DNA damage response. In this review, I describe the impact of targeting DNA damage response in cancer therapy and show how progress in radiation biology has contributed to the development of novel therapeutic strategies. (author)

  1. Radiations at the physics-biology interface. Utilization of radiations for research

    International Nuclear Information System (INIS)

    Douzou, P.

    1997-01-01

    Structural biology, which study the relation between the structure of biomolecules and their function, is at the interface between physics and biology. With the help of large radiation instruments such as X ray diffraction and neutron scattering, important advancements have been accomplished in the understanding of specific biological functions and led to the development of protein engineering (such as directed mutagenesis)

  2. [Biological effects of microwave radiation of low nonthermal intensity (regarding the maximal admissible values)].

    Science.gov (United States)

    Grigor'ev, Iu G; Shafirkin, A V; Vasin, A L

    2005-01-01

    There is still much controversy in scientific approaches to setting limits of exposure to radio-frequency electromagnetic radiation in Russia, Europe and USA. The stumbling stone is recognition or denial of potential risk of biological effects from nonthermal electromagnetic radiation (to 1 mW/cm2). The authors review results of experimental investigations performed in Russia over the years since 1960s to study the direct and delayed effects of ultra-high and microwave frequencies of low non-thermal intensity EMR, and delayed negative effects in employees based on the data of several follow-up epidemiological studies. This evidence was used as a baseline for establishing the Russian limits for chronic exposure to, thresholds of harmful effects and the maximal admissible values of EMR within the above frequencies.

  3. Radiation carcinogenesis: Epidemiology and biological significance

    International Nuclear Information System (INIS)

    Boice, J.D.; Fraumeni, J.F.

    1984-01-01

    Epidemiologic studies of populations exposed to radiation have led to the identification of a preventable cause of cancer, but in the long run perhaps the most important contribution of radiation studies will be to provide insights into the basic processes of human carcinogenesis. In this volume, key investigators of major epidemiologic projects summarize their observations to date, including information to help assess the effects of low-level exposures. Experimentalists and theorists emphasize the relevance of laboratory and epidemiologic data in elucidating carcinogenic risks and mechanisms in man. This volume was prepared with several objectives in mind: (a) organize and synthesize knowledge on radiation carcinogenesis through epidemiologic and experimental approaches; (b) illustrate and explore ways of utilizing this information to gain insights into the fundamental mechanisms of cancer development; (c) stimulate the formation of hypotheses suited to experimental or epidemiologic testing, theoretical modeling, and multidisciplinary approaches; and (d) identify recent advances that clarify dose-response relationships and the influence of low-dose exposures, provide leads to carcinogenic mechanisms and host-environmental interactions, and suggest strategies for future research and preventive action

  4. Rhagoletis cerasi Loew (Diptera: Tephritidae – Biological Characteristics, Harmfulness, and Control

    Directory of Open Access Journals (Sweden)

    Svetomir Stamenković

    2012-01-01

    Full Text Available The European cherry fruit fly, Rhagoletis cerasi Loew (Diptera: Tephritidae, is a highlydestructive pest in sweet and sour cherry orchards with a distribution area throughoutEurope and the temperate regions of Asia. It occurs regularly in all production regions ofthese fruit species in Serbia, damaging up to 10% of cherries in commercial production,while damage can go up to 100% in orchards and on solitary threes unprotected by controlmeasures.In Serbia, European cherry fruit fly most often attacks and damages fruits of the lateripeningcultivars of sweet cherry (Van, Stela, Hedelfinger, Bing, Lambert, Drogan’s Yellow.After a sweet cherry harvest, adults migrate to sour cherry where they continue feedingand ovipositing in half-mature sour cherries (prevailingly the domestic ecotype Oblačinska.During their activity period, larvae damage the fruits, so that they can no longer be consumedeither fresh or processed. The high percentage of sour cherries damaged by R. cerasihas become a factor limiting exports because the intensity of infestation of this fruitexceeds permissible limits. Pesticide use for controlling this pest, especially in integratedproduction, is based on a very poor selection of insecticides which cause problems withresidual ecotoxicity. Consequently, alternative measures for controlling European cherryfruit fly have been intensively studied over the past few years.This work surveys up-to-date results of various studies on the European cherry fruit flyas a very important pest in Serbia and other South and Mid-European countries. The workcontains detailed descriptions of its biological characteristics, flight phenology, infestationintensity and possibilities of fly control in sweet and sour cherry production areas.

  5. TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists

    International Nuclear Information System (INIS)

    Orton, C; Borras, C; Carlson, D

    2014-01-01

    Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protection will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 20–40 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples of how

  6. TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists

    Energy Technology Data Exchange (ETDEWEB)

    Orton, C [Wayne State University, Grosse Pointe, MI (United States); Borras, C [Radiological Physics and Health Services, Washington, DC (United States); Carlson, D [Yale University School of Medicine, New Haven, CT (United States)

    2014-06-15

    Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protection will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 20–40 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples of how

  7. Prevalence and Correlates of Worry About the Health Harms of Medical Imaging Radiation in the General Population.

    Science.gov (United States)

    Hay, Jennifer L; Gold, Geoffrey S; Baser, Raymond E; Hricak, Hedvig; Dauer, Lawrence T

    2016-10-01

    In recent years, there have been dramatic increases in medical imaging use and increasing media attention to increased exposure to ionizing radiation in the United States. Patient perspectives on medical imaging radiation (MIR) use is understudied, but could guide primary care discussions. This study examines prevalence of worry about the health harms from MIR in the US general population. This cross-sectional study used the 2012-2013 Health Information National Trends Survey conducted by the National Cancer Institute. A nationally representative sample (N = 3532) was drawn from the US general population to observe prevalence of worry about MIR as well as potential covariates, including demographic, medical, and psychological factors, health information-seeking, physician trust in providing cancer information, and cancer fatalism. About 65% of the sample population reported experiencing at least some worry about MIR. Univariable and multivariable logistic regressions indicate higher rates of MIR worry among women, racial/ethnic minorities, those with lower educational attainment, foreign-born Americans, those who self-report poorer health, and those with a personal history of cancer. Lower trust in cancer information from physicians and greater attention to cancer information from popular media were each associated with higher rates of worry about health harms of MIR. An accurate assessment of public worry about MIR will aid primary care providers' efforts to understand patient responses to medical imaging and identify addressable knowledge gaps regarding benefits and risks of medical imaging. These data may improve risk communication regarding medical imaging among referring primary care physicians, radiologists, and patients. © The Author(s) 2016.

  8. Light scattering on PHA granules protects bacterial cells against the harmful effects of UV radiation.

    Science.gov (United States)

    Slaninova, Eva; Sedlacek, Petr; Mravec, Filip; Mullerova, Lucie; Samek, Ota; Koller, Martin; Hesko, Ondrej; Kucera, Dan; Marova, Ivana; Obruca, Stanislav

    2018-02-01

    Numerous prokaryotes accumulate polyhydroxyalkanoates (PHA) in the form of intracellular granules. The primary function of PHA is the storage of carbon and energy. Nevertheless, there are numerous reports that the presence of PHA granules in microbial cells enhances their stress resistance and fitness when exposed to various stress factors. In this work, we studied the protective mechanism of PHA granules against UV irradiation employing Cupriavidus necator as a model bacterial strain. The PHA-accumulating wild type strain showed substantially higher UV radiation resistance than the PHA non-accumulating mutant. Furthermore, the differences in UV-Vis radiation interactions with both cell types were studied using various spectroscopic approaches (turbidimetry, absorption spectroscopy, and nephelometry). Our results clearly demonstrate that intracellular PHA granules efficiently scatter UV radiation, which provides a substantial UV-protective effect for bacterial cells and, moreover, decreases the intracellular level of reactive oxygen species in UV-challenged cells. The protective properties of the PHA granules are enhanced by the fact that granules specifically bind to DNA, which in turn provides shield-like protection of DNA as the most UV-sensitive molecule. To conclude, the UV-protective action of PHA granules adds considerable value to their primary storage function, which can be beneficial in numerous environments.

  9. Prototype Biology-Based Radiation Risk Module Project

    Science.gov (United States)

    Terrier, Douglas; Clayton, Ronald G.; Patel, Zarana; Hu, Shaowen; Huff, Janice

    2015-01-01

    Biological effects of space radiation and risk mitigation are strategic knowledge gaps for the Evolvable Mars Campaign. The current epidemiology-based NASA Space Cancer Risk (NSCR) model contains large uncertainties (HAT #6.5a) due to lack of information on the radiobiology of galactic cosmic rays (GCR) and lack of human data. The use of experimental models that most accurately replicate the response of human tissues is critical for precision in risk projections. Our proposed study will compare DNA damage, histological, and cell kinetic parameters after irradiation in normal 2D human cells versus 3D tissue models, and it will use a multi-scale computational model (CHASTE) to investigate various biological processes that may contribute to carcinogenesis, including radiation-induced cellular signaling pathways. This cross-disciplinary work, with biological validation of an evolvable mathematical computational model, will help reduce uncertainties within NSCR and aid risk mitigation for radiation-induced carcinogenesis.

  10. Cell kinetics and radiation biology (review)

    International Nuclear Information System (INIS)

    Denekamp, J.

    1986-01-01

    Variation in radiosensitivity around the cell cycle, and the extent of radiation-induced delay in cell cycle progression result in variable time of expression of radiation injury in normal tissues, ranging from a few days in intestine to weeks, months or years in slowly proliferating tissues. Radiosensitivity of tumours, to single doses, is dominated by hypoxic cells arising from the imbalance between tumour cell production and the proliferation and branching of blood vessels needed to bring oxygen and other nutrients to each cell. Response to fractionated radiotherapy schedules is also influenced by the cell kinetic parameters of the cells comprising each tissue or tumour. Slowly cycling cells show much more dramatic changes with fractionation, dose rate or l.e.t. Rapidly cycling cells redistribute around the cell cycle when the cells in sensitive phases have been killed, experiencing less mitotic delay than slowly proliferating cells. Reoxygenation seems more effective in tumours with rapidly cycling cells and high natural cell loss rates. Compensatory repopulation within a treatment schedule may spare skin and mucosa but not slowly proliferating tissues. Tumour cell proliferation during fractionated radiotherapy may be an important limiting factor of treatment success. (U.K.)

  11. Oxygen effect in radiation biology: caffeine and serendipity

    International Nuclear Information System (INIS)

    Kesavan, P.C.

    2005-01-01

    The 'hit theory' developed in 1920s to explain the actions of ionizing radiation on cells and organisms was purely physical, and its limitation was its inadequacy to address the contemporary findings such as the oxygen enhancement of radiobiological damage, and the increased radio- sensitivity of dividing compared to non-dividing cells. The textbooks written prior to 1970s did not either refer at all to oxygen as a radiosensitizer, or had mentioned it only in a passing manner; yet 'oxygen effect' was emerging as the central dogma in radiation biology. The oxygen effect in radiation biology is highly interdisciplinary encompassing atomic physics (i.e. interaction of photon with matter), radiation chemistry (formation of reactive oxygen species), molecular signalling, gene expression and genetic alterations in cells (mutation, cancer) or the cell death (apoptosis, necrosis, mitotic catastrophe, etc.). Cell death in higher organisms is now recognized as the precursor of possible error-free cell replacement repair. (author)

  12. Radiation physics, biophysics and radiation biology. Progress report, October 1, 1980-September 30, 1981

    International Nuclear Information System (INIS)

    1981-07-01

    Separate abstracts were prepared for the 29 papers in this progress report which deal with radiobiological physics, the biological effects of ionizing radiations, and the modification of these effects by chemical and pharmacological agents

  13. Radiation-resistant composite for biological shield of personnel

    Science.gov (United States)

    Barabash, D. E.; Barabash, A. D.; Potapov, Yu B.; Panfilov, D. V.; Perekalskiy, O. E.

    2017-10-01

    This article presents the results of theoretical and practical justification for the use of polymer concrete based on nonisocyanate polyurethanes in biological shield structures. We have identified the impact of ratio: polymer - radiation-resistant filling compound on the durability and protection properties of polymer concrete. The article expounds regression dependence of the change of basic properties of the aforementioned polymer concrete on the absorbed radiation dose rate. Synergy effect in attenuation of radioactivity release in case of conjoint use of hydrogenous polymer base and radiation-resistant powder is also addressed herein.

  14. Biological indicators for radiation absorbed dose: a review

    International Nuclear Information System (INIS)

    Paul, S.F.D.; Venkatachalam, P.; Jeevanram, R.K.

    1996-01-01

    Biological dosimetry has an important role to play in assessing the cumulative radiation exposure of persons working with radiation and also in estimating the true dose received during accidents involving external and internal exposure. Various biodosimetric methods have been tried to estimate radiation dose for the above purposes. Biodosimetric methods include cytogenetic, immunological and mutational assays. Each technique has certain advantages and disadvantages. We present here a review of each technique, the actual method used for detection of dose, the sensitivity of detection and its use in long term studies. (author)

  15. Environmental radiation: basic principles, biological facts, potential risks

    International Nuclear Information System (INIS)

    Rodemann, H.P.

    2000-01-01

    This book describes the complex processes that underlie the effects of different types of radiation at the cellular, organ and organismic level. Technical terms central to the subject matter are printed in italicize and explained in a glossary along with all physical quantities and dimensional units referred to. Through a systematic presentation of various aspects of the effects of environmental radiation on humans the author has endeavoured to make it clear that any discussion on potential health hazards must be conducted specific to the type of radiation in question. Furthermore, to study these issues meaningfully one must have a knowledge of the scientific basis of interactions between the various types of radiation and biological systems and be able to assess the relative impact of environmental radiation compared with other environmental health hazards

  16. Space Radiation and Manned Mission: Interface Between Physics and Biology

    Science.gov (United States)

    Hei, Tom

    2012-07-01

    The natural radiation environment in space consists of a mixed field of high energy protons, heavy ions, electrons and alpha particles. Interplanetary travel to the International Space Station and any planned establishment of satellite colonies on other solar system implies radiation exposure to the crew and is a major concern to space agencies. With shielding, the radiation exposure level in manned space missions is likely to be chronic, low dose irradiation. Traditionally, our knowledge of biological effects of cosmic radiation in deep space is almost exclusively derived from ground-based accelerator experiments with heavy ions in animal or in vitro models. Radiobiological effects of low doses of ionizing radiation are subjected to modulations by various parameters including bystander effects, adaptive response, genomic instability and genetic susceptibility of the exposed individuals. Radiation dosimetry and modeling will provide conformational input in areas where data are difficult to acquire experimentally. However, modeling is only as good as the quality of input data. This lecture will discuss the interdependent nature of physics and biology in assessing the radiobiological response to space radiation.

  17. Physics fundamentals and biological effects of synchrotron radiation therapy

    International Nuclear Information System (INIS)

    Prezado, Y.

    2010-01-01

    The main goal of radiation therapy is to deposit a curative dose in the tumor without exceeding the tolerances in the nearby healthy tissues. For some radioresistant tumors, like gliomas, requiring high doses for complete sterilization, the major obstacle for curative treatment with ionizing radiation remains the limited tolerance of the surrounding healthy tissue. This limitation is particularly severe for brain tumors and, especially important in children, due to the high risk of complications in the development of the central nervous system. In addition, the treatment of tumors close to an organ at risk, like the spinal cord, is also restricted. One possible solution is the development of new radiation therapy techniques exploiting radically different irradiation modes and modifying, in this way, the biological equivalent doses. This is the case of synchrotron radiation therapy (SRT). In this work the three new radiation therapy techniques under development at the European Synchrotron Radiation Facility (ESRF), in Grenoble (France) will be described, namely: synchrotron stereotactic radiation therapy (SSRT), microbeam radiation therapy (MRT) and minibeam radiation therapy. The promising results in the treatment of the high grade brain tumors obtained in preclinical studies have paved the way to the clinical trials. The first patients are expected in the fall of 2010. (Author).

  18. Biological radiation effects of Radon in Drosophila

    International Nuclear Information System (INIS)

    Pimentel P, A.E.

    1995-01-01

    In order to contribute to the knowledge on the effects of radon and its decay products, the aim of this investigation is to study the biological effects of radon using Drosophila melanogaster throught the somatic mutation and recombination test (SMART) and the analysis of some adaptative factors exposing larvaes to controlled radon atmosphers, considering that this insect could be used as biological monitor. Using the somatic mutation test a mutagenic effect was observed proportional to radon concentration, into an interval of 1 ± 0.3 to 111 ± 7.4 KBq/m 3 equivalent to doses under 0.0106 Gy. The correlation analysis gives a linear (r=0.80) relationship with a positive slope of 0.2217. The same happens when gamma rays are used in the interval of 1 to 20 Gy, given a linear dose-dependent effect (r=0.878) is obtained; nevetheless the slop is smaller (m=0.003) than for radon. Analysing the results of adaptative factors of the nine exposed generations, it was found that probably radon exposition induced dominant lethals during gametogenesis or/and a selection of the more component gamets of the treated individuals in larval state. It was reflected in the significant decrease on fecundity of the generation exposed. Nevertheless the laying eggs had an increase in egg-to-adult viability and the develop velocity was higher than in control for 3 KBq/m 3 , this suggest that radon concentrations used were able to induce repair mechanisms. These data agree with the Hormesis hypothesis that says: low doses have positive effects on health. It was not possible to obtain a dose-effect relationship except with the develop velocity where it was found a dose-effect inverse proportion. In conclusion, Drosophila melanogaster could be a good system to obtain in vivo damaged induction concentration dependent of radon and its decay products, as well as to study the effects in an exposed population by the analysis of adaptative factors. (Author)

  19. Sterilization of biological tissues with ionizing radiation

    International Nuclear Information System (INIS)

    Reyes F, M.L.; Martinez P, M.E.; Luna Z, D.

    1997-01-01

    On June 1994, the National Institute of Nuclear Research (ININ) and the South Central Hospital for High Specialty of PEMEX (HCSAE) began a joint work with the finality to obtain radio sterilized amniotic membranes for to be used as cover (biological bandage) in burnt patients. Subsequently the Chemistry Faculty of UNAM and the National Institute of Cardiology began to collaborate this last with interest on cardiac valves for graft. Starting from 1997, the International Atomic Energy Agency (IAEA) supports this project (MEX/7/008) whose main objective is to set up the basis to establish in Mexico a Radio sterilized Tissue Bank (amniotic membranes, skin, bones, tendons, cardiac valves, etc.) to be used with therapeutic purposes (grafts). The IAEA support has consisted in the equipment acquisition which is fundamental for the Tissue Bank performance such as an experimental irradiator, laminar flow bell, lyophilizer, vacuum sealer and special knives for tissues. Also visits to Mexico of experts have been authorized with the aim of advising to the personnel which participate in the project and scientific visits of this personnel to another tissue banks (Sri Lanka and Argentine). The establishment in Mexico of a Tissue bank will be a great benefit because it will have availability of distinct tissues for grafts and it will reduce the synthetic materials importation which is very expensive. (Author)

  20. Biological effects of space radiation and development of effective countermeasures

    Science.gov (United States)

    Kennedy, Ann R.

    2014-04-01

    As part of a program to assess the adverse biological effects expected from astronauts' exposure to space radiation, numerous different biological effects relating to astronauts' health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death and extracellular matrix (ECM) remodeling), oxidative stress, gastrointestinal tract bacterial translocation and immune system activation, peripheral hematopoietic cell counts, emesis, blood coagulation, skin, behavior/fatigue (including social exploration, submaximal exercise treadmill and spontaneous locomotor activity), heart functions, alterations in biological endpoints related to astronauts' vision problems (lumbar puncture/intracranial pressure, ocular ultrasound and histopathology studies), and survival, as well as long-term effects such as cancer and cataract development. A number of different countermeasures have been identified that can potentially mitigate or prevent the adverse biological effects resulting from exposure to space radiation.

  1. Solar ultraviolet radiation from cancer induction to cancer prevention: solar ultraviolet radiation and cell biology.

    Science.gov (United States)

    Tuorkey, Muobarak J

    2015-09-01

    Although decades have elapsed, researchers still debate the benefits and hazards of solar ultraviolet radiation (UVR) exposure. On the one hand, humans derive most of their serum 25-hydroxycholecalciferol [25(OH)D3], which has potent anticancer activity, from solar UVB radiation. On the other hand, people are more aware of the risk of cancer incidence associated with harmful levels of solar UVR from daily sunlight exposure. Epidemiological data strongly implicate UV radiation exposure as a major cause of melanoma and other cancers, as UVR promotes mutations in oncogenes and tumor-suppressor genes. This review highlights the impact of the different mutagenic effects of solar UVR, along with the cellular and carcinogenic challenges with respect to sun exposure.

  2. Biological shielding design calculation for agricultural radiation processing facility

    International Nuclear Information System (INIS)

    Petwal, V.C.; Sandha, R.S.; Soni, H.C.; Subbaiah, K.V.

    2005-01-01

    An electron beam radiation processing facility for agricultural products is being set-up at Centre for Advanced Technology Indore. The facility will be based on a pulsed linear accelerator and will be used in electron and photon modes to process various products e.g. onion, potato, home-pack items and medical products. When electron beam interact with structural components of accelerator or high Z-target used in photon mode, it generates intense Bremsstrahlung radiation field, which poses radiation protection problem. Biological shielding has been designed to provide protection against the generated radiation. Different conveying schemes and hence design of irradiation cell have been studied and results are presented for two promising designs. (author)

  3. Far infrared radiation (FIR): its biological effects and medical applications.

    Science.gov (United States)

    Vatansever, Fatma; Hamblin, Michael R

    2012-11-01

    Far infrared (FIR) radiation (λ = 3-100 μm) is a subdivision of the electromagnetic spectrum that has been investigated for biological effects. The goal of this review is to cover the use of a further sub-division (3- 12 μm) of this waveband, that has been observed in both in vitro and in vivo studies, to stimulate cells and tissue, and is considered a promising treatment modality for certain medical conditions. Technological advances have provided new techniques for delivering FIR radiation to the human body. Specialty lamps and saunas, delivering pure FIR radiation (eliminating completely the near and mid infrared bands), have became safe, effective, and widely used sources to generate therapeutic effects. Fibers impregnated with FIR emitting ceramic nanoparticles and woven into fabrics, are being used as garments and wraps to generate FIR radiation, and attain health benefits from its effects.

  4. The enhancement of biological ocular UV radiation on beaches compared to the radiation on grass.

    Science.gov (United States)

    Liu, Guang-Cong; Wang, Fang; Gao, Yan-Yan; Yang, Zheng; Hu, Li-Wen; Gao, Qian; Ri, Jun-Chol; Liu, Yang

    2014-12-01

    The influence of albedo on ocular UV exposure has seldom been reported. This paper aimed to explore the enhancement effect on measured ocular UV radiation due to a sand surface compared to measured ocular UV radiation due to a grass surface. We measured ambient and ocular UV radiation over the beach and grass surface in Sanya City of China (18.4°N, 109.7°E). The experimental apparatus was composed of a manikin and a dual-detector spectrometer. Integration of both UVA and UVB radiation was used to denote UV radiation. Then biologically effective ocular UVB radiation (UVBE) and the ratios of UVBE of two surfaces were calculated. Maximum of ocular UV radiation versus time over the two surfaces is bimodal. UVBE on the beach is significantly larger than UVBE on the sand, and UVBE peaked at different solar elevation angle (SEA) over the two surfaces (about 53° and 40° on the beach and grass, respectively, according to Bayesian regression). The maximum of ocular UVBE ratios is greater than two, which peaked SEA was about 50°. One hour's cumulative radiation under sunny weather exceeds thresholds for photokeratitis, conjunctivitis and lens damage. Higher albedo significantly increased biological ocular UV radiation. Tourists on tropical beaches should take protective measures and avoid facing the sun directly, especially when SEA is around 50°. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Advances in Physical and Biological Radiation Detectors. Proceedings of a Symposium on New Developments in Physical and Biological Radiation Detectors

    International Nuclear Information System (INIS)

    1971-01-01

    Radiation dosimetry is a fundamental part of all radiation protection work. The measurements are made with a variety of instruments, and health physicists, after professional interpretation of the data, can assess the levels of exposure which might be encountered in a given area or the individual doses received by workers, visitors and others at places where the possibility of radiation exposure exists. The types of radiation concerned here are photon radiations, ranging from soft X-rays to gamma rays, and particulate radiations such as β-rays, α-particles, protons, neutrons and fission fragments. The type of technique used depends not only on the type of radiation but also on such factors as whether the radiation is from a source internal or external to the body. Radiation dosimetry is not only used at nuclear facilities; it has diverse applications, for example in determining doses when radiation sources are employed for medical diagnostics and therapy, in safeguarding workers in any industry where isotopes are used, and in assessing the effect of both naturally occurring and man-made radiations on the general public and the environment. The advances of modern technology have increased the variety of sources; an example can be given from colour television, where the high potential necessary in certain colour cathode-ray tubes generates a non-negligible amount of X-rays. The Symposium on New Developments in Physical and Biological Radiation Detectors was one of a continuing series of meetings in which the International Atomic Energy Agency furthers the exchange of information on all aspects of personnel and area dosimetry. The Symposium was devoted in particular to a study of the dose meters themselves - their radiation-sensitive elements (both physical and biological),their instrumentation, and calibration and standardization. Several speakers suggested that the situation in the standardization and calibration of measuring equipment and sources was

  6. Assessment of the biological effects of 'strange' radiation

    International Nuclear Information System (INIS)

    Pryakhin, E.A.; Tryapitsina, G.A.; Urutskoyev, L.I.; Akleyev, A.V.

    2006-01-01

    The results from studies of the effects produced by electrical explosions of foils made from super pure materials in water point to the emergence of new chemical elements. An additional finding was the discharge of 'strange' radiation accompanying the transformation of chemical elements. However, currently, the mechanism involved in the interaction between 'strange' radiation and a substance or a biological entity remains obscure. Therefore, the aim of the present research is to investigate the biological effects of the 'strange' radiation. Pilot studies were performed at the RECOM RRC 'Kurchatov Institute' in April-May of 2004. The animals used in the experiment were female mice of C57Bl/6 line aged 80 days with body weight 16-18 g. The animals were exposed to radiation discharged during explosions of Ti foils in water and aqueous solutions. The cages with animals were placed at 1 m from the epicenter of the explosion. Explosions were carried out on the 19. (3 explosions), 20. (4 explosions) and 22. (3 explosions) of April, 2004 (explosions No1373 - No1382, respectively). The animals were assigned to 4 experimental groups comprised of 17-20 mice per group. The animals received experimental exposure within 1, 2 and 3 days of the experiment. In total, the experimental groups were exposed to 3, 7 and 10 explosions, respectively. In order to identify the biological reactions, the following parameters were estimated: number of nucleated cells in the bone marrow, number of CFU in the spleen after additional gamma-irradiation (6 Gy), cell composition of the bone marrow, the rate of erythrocytes with the different level of maturation in the bone marrow, the rate of erythrocytes with the micronuclei in the bone marrow, the reaction of bone marrow cells to additional gamma-irradiation (2 Gy), number of leucocytes in the peripheral blood, and cell composition of the peripheral blood. The following conclusions were drawn from these studies: 1. 'strange' radiation resulting

  7. View of environmental radiation effects from the study of radiation biology in C. elegans

    International Nuclear Information System (INIS)

    Sakashita, Tetsuya

    2011-01-01

    Caenorhabditis (C.) elegans is a non-parasitic soil nematode and is well-known as a unique model organism, because of its complete cell-lineage, nervous network and genome sequences. Also, C. elegans can be easily manipulated in the laboratory. These advantages make C. elegans as a good in vivo model system in the field of radiation biology. Radiation effects in C. elegans have been studied for three decades. Here, I briefly review the current knowledge of the biological effects of ionizing irradiation in C. elegans with a scope of environmental radiation effects. Firstly, basic information of C. elegans as a model organism is described. Secondly, historical view is reported on the study of radiation biology in C. elegans. Thirdly, our research on learning behavior is presented. Finally, an opinion of the use of C. elegans for environmental radiation protection is referred. I believe that C. elegans may be a good promising in vivo model system in the field of environmental radiation biology. (author)

  8. Cell phone radiation exposure on brain and associated biological systems.

    Science.gov (United States)

    Kesari, Kavindra Kumar; Siddiqui, Mohd Haris; Meena, Ramovatar; Verma, H N; Kumar, Shivendra

    2013-03-01

    Wireless technologies are ubiquitous today and the mobile phones are one of the prodigious output of this technology. Although the familiarization and dependency of mobile phones is growing at an alarming pace, the biological effects due to the exposure of radiations have become a subject of intense debate. The present evidence on mobile phone radiation exposure is based on scientific research and public policy initiative to give an overview of what is known of biological effects that occur at radiofrequency (RF)/ electromagnetic fields (EMFs) exposure. The conflict in conclusions is mainly because of difficulty in controlling the affecting parameters. Biological effects are dependent not only on the distance and size of the object (with respect to the object) but also on the environmental parameters. Health endpoints reported to be associated with RF include childhood leukemia, brain tumors, genotoxic effects, neurological effects and neurodegenerative diseases, immune system deregulation, allergic and inflammatory responses, infertility and some cardiovascular effects. Most of the reports conclude a reasonable suspicion of mobile phone risk that exists based on clear evidence of bio-effects which with prolonged exposures may reasonably be presumed to result in health impacts. The present study summarizes the public issue based on mobile phone radiation exposure and their biological effects. This review concludes that the regular and long term use of microwave devices (mobile phone, microwave oven) at domestic level can have negative impact upon biological system especially on brain. It also suggests that increased reactive oxygen species (ROS) play an important role by enhancing the effect of microwave radiations which may cause neurodegenerative diseases.

  9. Synchrotron radiation. 4. Analyses of biological samples using synchrotron radiation. 3. Research on radiation damage to DNA using synchrotron radiation

    International Nuclear Information System (INIS)

    Takakura, Kaoru

    1998-01-01

    This review described how the synchrotron radiation (SR) is used to solve problems unknown hitherto in radiation biology. Historically, the target substance of UV light in bacterial death was suggested to be nucleic acid in 1930. Researches on the radiation damage to DNA were begun at around 1960 and have mainly used UV light, X-ray and γray. Soft X-ray and vacuum UV whose energy covering from several eV to scores of keV have not been used since UV and X-ray lack the energy of this range. This is one of reasons why detailed process leading to radiation-induced death, carcinogenicity and mutation has not been known hitherto. RS possesses wide range of energy, i.e., from UV to hard X-ray, of high intensity, which is helpful for studying the unknown problems. The RS studies were begun in nineteen-seventies. Those include the action spectrum studies and atomic target studies. In the former, the course of the effect, e.g., the mechanism of DNA double strand breakage, can be elucidated. In the latter, photon of known energy can be irradiated to the specified atom like phosphorus in DNA which elucidating the precise physicochemical process of the breakage. Use of RS in these studies is thought still meaningful in future. (K.H.) 62 refs

  10. 5. Conference cycle. The radiations and the Biological Sciences

    International Nuclear Information System (INIS)

    Balcazar G, M.; Chavez B, A.

    1991-06-01

    Nuclear technologies and their development have influenced many aspects of modern life. Besides used for electricity production nuclear technologies are applied in many other fields, especially in biological sciences. In genetics and molecular biology they enable research resulting in increased food production and better food preservation. Usage in material sciences lead to new varieties of plastics or improved characteristics. Nuclear applications are used in pe troleum industries and in forecasting geothermic power. Radiobiology and radiotherapy enable diagnosis and therapy of several diseases, e.g. cancer. Nuclear technologies also contribute to preserve the environment. They offer methods to analyse as well as decrease the environmental impacts. The 5. conference cyle entitled 'The Radiations and the Biological Sciences' aims to inform students of biological sciences about new nuclear technologies applied in their field of interest

  11. Biological Complexities in Radiation Carcinogenesis and Cancer Radiotherapy: Impact of New Biological Paradigms

    Directory of Open Access Journals (Sweden)

    Hossein Mozdarani

    2012-01-01

    Full Text Available Although radiation carcinogenesis has been shown both experimentally and epidemiologically, the use of ionizing radiation is also one of the major modalities in cancer treatment. Various known cellular and molecular events are involved in carcinogenesis. Apart from the known phenomena, there could be implications for carcinogenesis and cancer prevention due to other biological processes such as the bystander effect, the abscopal effect, intrinsic radiosensitivity and radioadaptation. Bystander effects have consequences for mutation initiated cancer paradigms of radiation carcinogenesis, which provide the mechanistic justification for low-dose risk estimates. The abscopal effect is potentially important for tumor control and is mediated through cytokines and/or the immune system (mainly cell-mediated immunity. It results from loss of growth and stimulatory and/or immunosuppressive factors from the tumor. Intrinsic radiosensitivity is a feature of some cancer prone chromosomal breakage syndromes such as ataxia telangectiasia. Radiosensitivity is manifested as higher chromosomal aberrations and DNA repair impairment is now known as a good biomarker for breast cancer screening and prediction of prognosis. However, it is not yet known whether this effect is good or bad for those receiving radiation or radiomimetic agents for treatment. Radiation hormesis is another major concern for carcinogenesis. This process which protects cells from higher doses of radiation or radio mimic chemicals, may lead to the escape of cells from mitotic death or apoptosis and put cells with a lower amount of damage into the process of cancer induction. Therefore, any of these biological phenomena could have impact on another process giving rise to genome instability of cells which are not in the field of radiation but still receiving a lower amount of radiation. For prevention of radiation induced carcinogenesis or risk assessment as well as for successful radiation

  12. Radiation Biology: A Handbook for Teachers and Students

    International Nuclear Information System (INIS)

    2010-01-01

    Knowledge of the radiobiology of normal tissues and tumours is a core prerequisite for the practice of radiation oncology. As such the study of radiobiology is mandatory for gaining qualification as a radiation oncologist in most countries. Teaching is done partly by qualified radiobiologists in some countries, and this is supplemented by teaching from knowledgeable radiation oncologists. In low and middle income (LMI) countries the teachers are often radiation oncologists and/or medical physicists. In Europe, a master's course on radiobiology is taught jointly by a consortium of five European Universities. This is aimed at young scientists from both Western and Eastern Europe, training in this discipline. Recently the European Society for Therapeutic Radiology and Oncology (ESTRO) initiated the launch of a radiobiology teaching course outside Europe (Beijing, 2007; Shanghai, 2009). Radiation protection activities are governed by many regulations and recommendations. These are based on knowledge gained from epidemiological studies of health effects from low as well as from high dose radiation exposures. Organizations like the International Commission on Radiological Protection (ICRP) have put a lot of effort into reviewing and evaluating the biological basis to radiological protection practices. Personnel being trained as future radiation protection personnel should have a basic understanding of the biological and clinical basis to the exposure limitations that they are subject to and that they implement for industrial workers and the public at large. It is for these reasons that aspects of Radiobiology related to protection issues are included in this teaching syllabus. In LMI countries, many more teachers are needed in radiobiology, and the establishment of regional training centres or special regional training courses in radiobiology, are really the only options to solve the obvious deficit in knowledge of radiobiology in such countries. Radiobiology teaching

  13. Effects of UV and microwave radiation on biological material

    International Nuclear Information System (INIS)

    Fielitz, J.; Boegl, W.; Stockhausen, K.; Kossel, F.

    1977-01-01

    For the present study, ten publications on the effect of UV radiation were analyzed. In vitro tests were carried out with one biological substance and seven different human or animal organs and biocytocultures. In vivo, three bacterial strains were irradiated and four irradiation experiments were carried out on mice. As to the effect of microwave radiation, eleven publications were analyzed. In vitro tests were carried out with one biological substance and three animal organs. In vivo, one bacterial strain was irradiated and eight irradiation experiments were carried out on different types of animals. The study's aim was to obtain a survey on biochemical changes of the organisms. Phenomenological changes were given only when the corresponding articles contained further investigation results. Behavioral changes were not taken into account. The results published by the authors of the original papers were compiled in a kind of dictionary. All relevant data are listed in a defined order. (orig.) [de

  14. Environmental mutagenesis and radiation biology: The legacy of William Morgan.

    Science.gov (United States)

    Schwartz, Jeffrey L

    2017-12-01

    A symposium entitled Environmental Mutagenesis and Radiation Biology was held on September 27, 2016 to honor the memory of Dr. William F. Morgan who passed away unexpectedly on November 13, 2015. The speakers presented the latest reviews on homologous recombination repair, induced genetic instability, bystander effects, and risk estimate development. Their presentations are presented following the introduction. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Radiation processing of biological tissues for nuclear disaster management

    International Nuclear Information System (INIS)

    Singh, Rita

    2012-01-01

    A number of surgical procedures require tissue substitutes to repair or replace damaged or diseased tissues. Biological tissues from human donor like bone, skin, amniotic membrane and other soft tissues can be used for repair or reconstruction of the injured part of the body. Tissues from human donor can be processed and banked for orthopaedic, spinal, trauma and other surgical procedures. Allograft tissues provide an excellent alternative to autografts. The use of allograft tissue avoids the donor site morbidity and reduces the operating time, expense and trauma associated with the acquisition of autografts. Further, allografts have the added advantage of being available in large quantities. This has led to a global increase in allogeneic transplantation and development of tissue banking. However, the risk of infectious disease transmission via tissue allografts is a major concern. Therefore, tissue allografts should be sterilized to make them safe for clinical use. Radiation processing has well appreciated technological advantages and is the most suitable method for sterilization of biological tissues. Radiation processed biological tissues can be provided by the tissue banks for the management of injuries due to a nuclear disaster. A nuclear detonation will result in a large number of casualties due to the heat, blast and radiation effects of the weapon. Skin dressings or skin substitutes like allograft skin, xenograft skin and amniotic membrane can be used for the treatment of thermal burns and radiation induced skin injuries. Bone grafts can be employed for repairing fracture defects, filling in destroyed regions of bone, management of open fractures and joint injuries. Radiation processed tissues have the potential to repair or reconstruct damaged tissues and can be of great assistance in the treatment of injuries due to the nuclear weapon. (author)

  16. Overview. Department of Radiation and Environmental Biology. Section 7

    Energy Technology Data Exchange (ETDEWEB)

    Cebulska-Wasilewska, A. [Institute of Nuclear Physics, Cracow (Poland)

    1995-12-31

    The activities of the Department of Radiation and Environmental Biology in 1994 cover the following goals: application of fission neutrons to cancer therapy, studies on neutron efficiency to induce mutation and chromosomal damage, study on the formula for alteration of the repair process observed in case of gene mutation in TSH assay, investigation of new methods for more accurate measurements of molecular and cellular damage caused by radiation and environmental agents and studies on possible improvement in the application of different radiation sources to clinical cancer therapy. In this section of the Annual Report, the description of the mentioned activities as well as the information about personnel employed in the Department, papers and reports published in 1994, contribution to conferences and grants are also given.

  17. Biological monitors for low levels of ionising radiation

    International Nuclear Information System (INIS)

    Mohankumar, M.N.; Jeevanram, R.K.

    1995-01-01

    The biological effects of high doses of ionising radiation are well understood and the methods of measurement of these doses well established. However the effects due to extremely low doses remain by and large uncertain. This is because of the fact that at such low doses no gross symptoms are seen. In fact, at these levels the occurrence of double strand breaks leading to the formation of chromosomal aberrations like dicentrics is rare and chances of mutation due to base damage are negligible. Hence neither chromosomal aberration studies nor mutational assays are useful for detecting doses of the order of a few milligray. Results of exhaustive work done by various laboratories indicate that below 20 mGy the chromosomal aberration technique based on scoring of dicentrics cannot distinguish between a linear or a threshold model. However indirect methods like unscheduled DNA synthesis (UDS) and sister chromatid exchanges (SCEs) appear to be promising for the detection of radiation exposures due to low levels of radiation. This report reviews the available literature on the biological effects of low levels of ionising radiation and highlights the merits and demerits of the various methods employed in the measurement of UDS and SCE. The phenomenon of radio-adaptive response (RAR) and its relation to DNA repair is also discussed. (author)

  18. Radiation damage and repair in cells and cell components. Part 2. Physical radiations and biological significance. Final report

    International Nuclear Information System (INIS)

    Fluke, D.J.

    1984-08-01

    The report comprises a teaching text, encompassing all physical radiations likely to be of biological interest, and the relevant biological effects and their significance. Topics include human radiobiology, delayed effects, radiation absorption in organisms, aqueous radiation chemistry, cell radiobiology, mutagenesis, and photobiology

  19. Personal recollections of radiation biology research at Hanford

    International Nuclear Information System (INIS)

    Thompson, R.C.

    1995-01-01

    This paper traces the evolution of the Hanford biology programme over a period of nearly five decades. The programme began in the 1940s with a focus on understanding the potential health effects of radionuclides such as 131 I associated with fallout from the atomic bomb. These studies were extended in the 1950s to experiments on the toxicity and metabolism of plutonium and fission products such as 90 Sr and 137 Cs. In the 1960s, a major long term project was initiated on the inhalation toxicology and carcinogenic effects of plutonium oxide and plutonium nitrate in dogs and rodents. The project remained a major effort within the overall Hanford biology programme throughout the 1970s and 1980s, during which time a broad range of new projects on energy-related pollutants, radon health effects, and basic radiation biology were initiated. Despite the many evolutionary changes that have occurred in the Hanford biology programme, the fundamental mission of understanding the effects of radiation on human health has endured for nearly five decades. (author)

  20. Breast Cancer Biology: Clinical Implications for Breast Radiation Therapy.

    Science.gov (United States)

    Horton, Janet K; Jagsi, Reshma; Woodward, Wendy A; Ho, Alice

    2018-01-01

    Historically, prognosis and treatment decision making for breast cancer patients have been dictated by the anatomic extent of tumor spread. However, in recent years, "breast cancer" has proven to be a collection of unique phenotypes with distinct prognoses, patterns of failure, and treatment responses. Recent advances in biologically based assays and targeted therapies designed to exploit these unique phenotypes have profoundly altered systemic therapy practice patterns and treatment outcomes. Data associating locoregional outcomes with tumor biology are emerging. However, the likelihood of obtaining level I evidence for fundamental radiation therapy questions within each of the specific subtypes in the immediate future is low. As such, this review aims to summarize the existing data and provide practical context for the incorporation of breast tumor biology into clinical practice. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1992--November 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood ``biological fingerprint`` of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  2. Complex systems of biological interest stability under ionising radiations

    International Nuclear Information System (INIS)

    Maclot, Sylvain

    2014-01-01

    This PhD work presents the study of stability of molecular systems of biological interest in the gas phase after interaction with ionising radiations. The use of ionising radiation can probe the physical chemistry of complex systems at the molecular scale and thus consider their intrinsic properties. Beyond the fundamental aspect, this work is part of the overall understanding of radiation effects on living organisms and in particular the use of ionizing radiation in radiotherapy. Specifically, this study focused on the use of low-energy multiply charged ions (tens of keV) provided by the GANIL (Caen), which includes most of the experiments presented. In addition, experiments using VUV photons were also conducted at synchrotron ELETTRA (Trieste, Italy). The bio-molecular systems studied are amino acids and nucleic acid constituents. Using an experimental crossed beams device allows interaction between biomolecules and ionising radiation leads mainly to the ionization and fragmentation of the system. The study of its relaxation dynamics is by time-of-flight mass spectrometry coupled to a coincidences measurements method. It is shown that an approach combining experiment and theory allows a detailed study of the fragmentation dynamics of complex systems. The results indicate that fragmentation is generally governed by the Coulomb repulsion but the intramolecular rearrangements involve specific relaxation mechanisms. (author) [fr

  3. The biological effects of exposure to ionising radiation

    International Nuclear Information System (INIS)

    Higson, D.J.

    2016-01-01

    Scenarios for exposure to ionising radiation range from natural background radiation (chronic) to the explosions of atomic bombs (acute), with some medical, industrial and research exposures lying between these extremes. Biological responses to radiation that predominate at high doses incurred at high dose rates are different from those that predominate at low doses and low dose rates. Single doses from bomb explosions ranged up to many thousand mGy. Acute doses greater than about 1000 mGy cause acute radiation syndrome (ARS). Below this threshold, radiation has a variety of potential latent health effects: Change to the incidence of cancer is the most usual subject of attention but change to longevity may be the best overall measure because decreased incidences of non-cancer mortality have been observed to coincide with increased incidence of cancer mortality. Acute doses greater than 500 mGy cause increased risks of cancer and decreased life expectancy. For doses less than 100 mGy, beneficial overall health effects ('radiation hormesis') have been observed. At the other end of the spectrum, chronic exposure to natural radiation has occurred throughout evolution and is necessary for the normal life and health of current species. Dose rates greater than the present global average of about 2 mGy per year have either no discernible health effect or beneficial health effects up to several hundred mGy per year. It is clearly not credible that a single health effects model -- such as the linear no-threshold (LNT) model of risk estimation -- could fit all latent health effects. A more realistic model is suggested.

  4. Radiation physics, biophysics, and radiation biology: Progress report, December 1, 1987-November 30, 1988

    International Nuclear Information System (INIS)

    Hall, E.J.; Zaider, M.; Delegianis, M.J.

    1988-07-01

    Research at the Radiological Research Laboratory is a blend of physics, chemistry, and biology, involving research at the basic level with the admixture of a small proportion of pragmatic or applied research in support of radiation protection and/or radiation therapy. At the current level of funding, approximately one quarter of the research of the Laboratory could be regarded as in support of radiotherapy, with the remainder addressing more basic issues. The new initiatives have been in two directions. First, there has been an increased emphasis on research in radiation chemistry, inasmuch as this subject which involves the study of free radicals and fast radiation chemistry processes starts to bridge the gap between physics and biology, between the initial deposition of radiant energy and its final expression in terms of biological consequences. Second, the emphasis in the biological research has moved towards studies at the molecular level, with the appointment of new members of staff with expertise in this area. Individual chapters were processed separately for the data base

  5. Biological effects of low-dose ionizing radiation exposure; Biologische Wirkungen niedriger Dosen ionisierender Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Reinoehl-Kompa, Sabine; Baldauf, Daniela; Heller, Horst (comps.)

    2009-07-01

    The report on the meeting of the Strahlenschutzkommission 2007 concerning biological effects of low-dose ionizing radiation exposure includes the following contributions: Adaptive response. The importance of DNA damage mechanisms for the biological efficiency of low-energy photons. Radiation effects in mammography: the relative biological radiation effects of low-energy photons. Radiation-induced cataracts. Carcinomas following prenatal radiation exposure. Intercellular apoptosis induction and low-dose irradiation: possible consequences for the oncogenesis control. Mechanistic models for the carcinogenesis with radiation-induced cell inactivation: application to all solid tumors in the Japanese atomic bomb survivors. Microarrays at low radiation doses. Mouse models for the analysis of biological effects of low-dose ionizing radiation. The bystander effect: observations, mechanisms and implications. Lung carcinoma risk of Majak workers - modeling of carcinogenesis and the bystander effect. Microbeam studies in radiation biology - an overview. Carcinogenesis models with radiation-induced genomic instability. Application to two epidemiological cohorts.

  6. American Society for Radiation Oncology (ASTRO) Survey of Radiation Biology Educators in U.S. and Canadian Radiation Oncology Residency Programs

    International Nuclear Information System (INIS)

    Rosenstein, Barry S.; Held, Kathryn D.; Rockwell, Sara; Williams, Jacqueline P.; Zeman, Elaine M.

    2009-01-01

    Purpose: To obtain, in a survey-based study, detailed information on the faculty currently responsible for teaching radiation biology courses to radiation oncology residents in the United States and Canada. Methods and Materials: In March-December 2007 a survey questionnaire was sent to faculty having primary responsibility for teaching radiation biology to residents in 93 radiation oncology residency programs in the United States and Canada. Results: The responses to this survey document the aging of the faculty who have primary responsibility for teaching radiation biology to radiation oncology residents. The survey found a dramatic decline with time in the percentage of educators whose graduate training was in radiation biology. A significant number of the educators responsible for teaching radiation biology were not fully acquainted with the radiation sciences, either through training or practical application. In addition, many were unfamiliar with some of the organizations setting policies and requirements for resident education. Freely available tools, such as the American Society for Radiation Oncology (ASTRO) Radiation and Cancer Biology Practice Examination and Study Guides, were widely used by residents and educators. Consolidation of resident courses or use of a national radiation biology review course was viewed as unlikely by most programs. Conclusions: A high priority should be given to the development of comprehensive teaching tools to assist those individuals who have responsibility for teaching radiation biology courses but who do not have an extensive background in critical areas of radiobiology related to radiation oncology. These findings also suggest a need for new graduate programs in radiobiology.

  7. Exotic harmful algae in marine ecosystems: an integrated biological-economic-legal analysis of impacts and policies

    NARCIS (Netherlands)

    van den Bergh, J.C.J.M.; Nunes, P.A.L.D.; Dottinga, H.M.; Kooistra, W.H.C.F.; Vrieling, E.G.; Peperzak, L.

    2002-01-01

    Harmful algal blooms (HABs) are the cause of important damages to marine living resources and human beings. HABs are generated by micro-algae. These marine species are primarily introduced through ballast water of ships and, to a lesser extent, through import of living fish, in particular shellfish.

  8. Exotic harmful algae in marine ecosystems : an integrated biological-economic-legal analysis of impacts and policies

    NARCIS (Netherlands)

    van den Bergh, JCJM; Nunes, PALD; Dotinga, HM; Kooistra, WHCF; Vrieling, EG; Peperzak, L

    Harmful algal blooms (HABs) are the cause of important damages to marine living resources and human beings. HABs are generated by micro-algae. These marine species are primarily introduced through ballast water of ships and, to a lesser extent, through import of living fish, in particular shellfish.

  9. Studies on the Promotion of Biological Application by Radiation

    International Nuclear Information System (INIS)

    No, Y. C.; Kuk, I. H.; Song, H. S.

    2006-03-01

    Radiation Technology (RT) has been widely used in most of all fields of industries, medical, bioresources, food and agriculture, public hygiene, and environment. Therefore, its application has been also researched in various parts. For industrialization of the developed technology, not only the application technology will be developed, but the accurate dosimetry and improvement of the services of irradiation practice should be performed as soon as possible. Evaluation of effects and reaction mechanism of biological materials by irradiation was performed in this year in the long term research planning. The researches and experiments were well performed and the good results were obtained. The results may be donated in the progress of radiation biology and the new establishment on the application of RT. Also, one of the results was the evaluation of the structural changes of biomolecules and its application in the fields of food and biotechnology industries. Advanced Radiation Technology Institute (ARTI) will be well settled down and promotion of research activity of newly established institute by the fundamental support of KAERI. And, ARTI can get the goal where the vision of the hub of RT in Asia/Pacific region by 2020

  10. Biological effects and medical applications of infrared radiation.

    Science.gov (United States)

    Tsai, Shang-Ru; Hamblin, Michael R

    2017-05-01

    Infrared (IR) radiation is electromagnetic radiation with wavelengths between 760nm and 100,000nm. Low-level light therapy (LLLT) or photobiomodulation (PBM) therapy generally employs light at red and near-infrared wavelengths (600-100nm) to modulate biological activity. Many factors, conditions, and parameters influence the therapeutic effects of IR, including fluence, irradiance, treatment timing and repetition, pulsing, and wavelength. Increasing evidence suggests that IR can carry out photostimulation and photobiomodulation effects particularly benefiting neural stimulation, wound healing, and cancer treatment. Nerve cells respond particularly well to IR, which has been proposed for a range of neurostimulation and neuromodulation applications, and recent progress in neural stimulation and regeneration are discussed in this review. The applications of IR therapy have moved on rapidly in recent years. For example, IR therapy has been developed that does not actually require an external power source, such as IR-emitting materials, and garments that can be powered by body heat alone. Another area of interest is the possible involvement of solar IR radiation in photoaging or photorejuvenation as opposites sides of the coin, and whether sunscreens should protect against solar IR? A better understanding of new developments and biological implications of IR could help us to improve therapeutic effectiveness or develop new methods of PBM using IR wavelengths. Copyright © 2016. Published by Elsevier B.V.

  11. Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects

    Science.gov (United States)

    Kennedy, Ann

    The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-β1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together

  12. The biological effects of ionising radiation on Crustaceans: A review

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Neil; Lerebours, Adélaïde [Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth, Ferry Road, Portsmouth, Hampshire PO4 9LY (United Kingdom); Smith, Jim T. [School of Earth & Environmental Sciences, University of Portsmouth, Burnaby Building, Burnaby Road, Portsmouth, Hampshire PO1 3QL (United Kingdom); Ford, Alex T., E-mail: alex.ford@port.ac.uk [Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth, Ferry Road, Portsmouth, Hampshire PO4 9LY (United Kingdom)

    2015-10-15

    Highlights: • We comprehensively review the effects of ionising radiation in crustaceans. • Current environmental radioprotection levels found to be inadequate in some cases. • Mutation is shown to be a sensitive endpoint of radiation exposure. • Lowest observed effect dose rate varies by orders of magnitude. - Abstract: Historic approaches to radiation protection are founded on the conjecture that measures to safeguard humans are adequate to protect non-human organisms. This view is disparate with other toxicants wherein well-developed frameworks exist to minimise exposure of biota. Significant data gaps for many organisms, coupled with high profile nuclear incidents such as Chernobyl and Fukushima, have prompted the re-evaluation of our approach toward environmental radioprotection. Elucidating the impacts of radiation on biota has been identified as priority area for future research within both scientific and regulatory communities. The crustaceans are ubiquitous in aquatic ecosystems, comprising greater than 66,000 species of ecological and commercial importance. This paper aims to assess the available literature of radiation-induced effects within this subphylum and identify knowledge gaps. A literature search was conducted pertaining to radiation effects on four endpoints as stipulated by a number of regulatory bodies: mortality, morbidity, reproduction and mutation. A major finding of this review was the paucity of data regarding the effects of environmentally relevant radiation doses on crustacean biology. Extremely few studies utilising chronic exposure durations or wild populations were found across all four endpoints. The dose levels at which effects occur was found to vary by orders of magnitude thus presenting difficulties in developing phyla-specific benchmark values and reference levels for radioprotection. Based on the limited data, mutation was found to be the most sensitive endpoint of radiation exposure, with mortality the least sensitive

  13. Towards Space Exploration of Moon, Mars Neos: Radiation Biological Basis

    Science.gov (United States)

    Hellweg, Christine; Baumstark-Khan, Christa; Berger, Thomas; Reitz, Guenther

    2016-07-01

    Radiation has emerged as the most critical issue to be resolved for long-term missions both orbital and interplanetary. Astronauts are constantly exposed to galactic cosmic radiation (GCR) of various energies with a low dose rate. Primarily late tissue sequels like genetic alterations, cancer and non-cancer effects, i.e. cataracts and degenerative diseases of e.g. the central nervous system or the cardiovascular system, are the potential risks. Cataracts were observed to occur earlier and more often in astronauts exposed to higher proportions of galactic ions (Cucinotta et al., 2001). Predictions of cancer risk and acceptable radiation exposure in space are subject to many uncertainties including the relative biological effectiveness (RBE) of space radiation especially heavy ions, dose-rate effects and possible interaction with microgravity and other spaceflight environmental factors. The initial cellular response to radiation exposure paves the way to late sequelae and starts with damage to the DNA which complexity depends on the linear energy transfer (LET) of the radiation. Repair of such complex DNA damage is more challenging and requires more time than the repair of simple DNA double strand breaks (DSB) which can be visualized by immunofluorescence staining of the phosphorylated histone 2AX (γH2AX) and might explain the observed prolonged cell cycle arrests induced by high-LET in comparison to low-LET irradiation. Unrepaired or mis-repaired DNA DSB are proposed to be responsible for cell death, mutations, chromosomal aberrations and oncogenic cell transformation. Cell killing and mutation induction are most efficient in an LET range of 90-200 keV/µm. Also the activation of transcription factors such as Nuclear Factor κB (NF-κB) and gene expression shaping the cellular radiation response depend on the LET with a peak RBE between 90 and 300 keV/µm. Such LET-RBE relationships were observed for cataract and cancer induction by heavy ions in laboratory animals

  14. Radiation exposure and the woman worker: biological and legal parameters

    International Nuclear Information System (INIS)

    Carver, J.S.

    1976-01-01

    The interpretation of federal and state legislation and regulations concerning the radiation protection of women in the workplace has not been a clear and straightforward procedure. On one hand, the safety of all workers, independent of sex, imposes a specific directive for the enforcement of working standards in general. On the other hand, must allowance be made in setting radiation standards for the particular biological characteristics of workers, some of whom are women. Title VII of the Civil Rights Act provides equal employment opportunity for women and is now being enforced. All legal questions aside, men and women are decidedly different in one aspect; only women can conceive and carry a fetus and studies have shown that, in humans, the most radiosensitive stage of the fetus is during the first trimester of pregnancy. Possible legal and socio-economic aspects of questions posed by the employment of women by the nuclear industry are considered

  15. Biological efficiency of interaction between various radiation and chemicals

    International Nuclear Information System (INIS)

    Kim, Jin Kyu; Yu, Dong Han; Lee, Byoung Hun; Petin, Vladislav G.; Geras'kin, Stanislav A.; Cebulska-Wasilewska, Antonina; Panek, Agnieszka; Wiechec, Anna

    2004-06-01

    This research project has been carried out jointly with INP (Poland) to develop technologies to assess the biological efficiency of interaction between radiation and chemicals. Through the cooperative project, KAERI and INP have established wide variety of bioassay techniques applicable to radiation bioscience, human monitoring, molecular epidemiology and environmental science. The joint experiment, in special, made it possible to utilize the merits of both institutes and to upgrade and verify KAERI's current technology level. All results of the cooperative research will be jointly published in high standard scientific journals listed in the Science Citation Index (SCI), which can make the role of fundamental basis for improving relationship between Korea and Poland. Research skills such as Trad-MCN assay, SCGE assay, immunohistochemical assay and molecular assay developed through joint research will be further elaborated and will be continuously used for the collaboration between two institutes

  16. Biological Effects of EM Radiations from Mobile Phones

    Directory of Open Access Journals (Sweden)

    Adel A. Ali

    2002-06-01

    Full Text Available Direct health effects could result following exposure to RF by thermal (heating effects. Recent Studies have shown that there are public fears on effects that can be caused mainly by holding mobile phones close to the body, or as a result of possible non-thermal effects from both phones and base stations.  This paper offers an overview on the biological effects of electromagnetic radiation caused by mobile phones. Exposures of individuals to RF radiation from these sources will depend upon their proximity and may be above those from mobile phone base stations, although still well below guidelines. From a review of the scientific literature, it is concluded that there were no established health effects from exposure to the RF fields from mobile phones. However, there are gaps in knowledge requiring further research, but current knowledge suggests that RF exposure to levels below the guidelines were not a risk to health.

  17. Harm reduction

    OpenAIRE

    Normand, Jacques; Li, Jih-Heng; Thomson, Nicholas; Jarlais, Don Des

    2013-01-01

    The “Harm Reduction” session was chaired by Dr. Jacques Normand, Director of the AIDS Research Program of the U.S. National Institute on Drug Abuse. The three presenters (and their presentation topics) were: Dr. Don Des Jarlais (High Coverage Needle/Syringe Programs for People Who Inject Drugs in Low and Middle Income Countries: A Systematic Review), Dr. Nicholas Thomson (Harm Reduction History, Response, and Current Trends in Asia), and Dr. Jih-Heng Li (Harm Reduction Strategies in Taiwan).

  18. Biological dosimetry of ionizing radiation by chromosomal aberration analysis

    International Nuclear Information System (INIS)

    Gonzalez-Castano, S.; Silva, A.; Navlet, J.

    1990-01-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study ol chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 degree celsius has been produced. Experimental data is fitted to model Y =α + β 1 D + β 2 D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 14 refs

  19. Biological rhythms for rehabilitation of radiation damage of population

    International Nuclear Information System (INIS)

    Goncharova, T.G.; Vasil'eva, G.S.; Efimov, M.L.

    1999-01-01

    Considerable disturbances in biological eurhythmycal structure of redoracu were discovered for people living in Borodulikha area of the Semipalatinsk test site. The deep desynchronise may result in a development of the cardiovascular, bronco-pulmonary, endocrine, oncologic, neuro psychic diseases. A method to correct the biological eurhythmycal structure was developed. Homeopathic doses of melatonin ('rhythm driver' managing the most regenerating and immune systems) and uthynol (promoting production of dehydroepiandrosterone of maternal prehormone of 27 hormones) were used to provide the general correction. The endocrine diseases are not practically subjected to the homeopathic correction. The sub correction was sometimes carried out after 5 months. The developed methods of rehabilitation of the radiation damages are unique, since they allow performing the homeopathic correction using the acupuncture monitoring

  20. Biological dosimetry of ionizing radiation by chromosomal aberration analysis

    International Nuclear Information System (INIS)

    Navlet Armenta, J.M.; Gonzalez, S.; Silva, A.

    1990-01-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haemathological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study of chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 o C has been produced. Experimental data is fitted to model Y = α+β 1 D+β 2 D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author)

  1. Advances in radiation biology: Relative radiation sensitivities of human organ systems. Volume 12

    Energy Technology Data Exchange (ETDEWEB)

    Lett, J.T.; Altman, K.I.; Ehmann, U.K.; Cox, A.B.

    1987-01-01

    This volume is a thematically focused issue of Advances in Radiation Biology. The topic surveyed is relative radiosensitivity of human organ systems. Topics considered include relative radiosensitivities of the thymus, spleen, and lymphohemopoietic systems; relative radiosensitivities of the small and large intestine; relative rediosensitivities of the oral cavity, larynx, pharynx, and esophagus; relative radiation sensitivity of the integumentary system; dose response of the epidermal; microvascular, and dermal populations; relative radiosensitivity of the human lung; relative radiosensitivity of fetal tissues; and tolerance of the central and peripheral nervous system to therapeutic irradiation.

  2. Which benefits and harms of preoperative radiotherapy should be addressed? A Delphi consensus study among rectal cancer patients and radiation oncologists

    International Nuclear Information System (INIS)

    Kunneman, Marleen; Pieterse, Arwen H.; Stiggelbout, Anne M.; Marijnen, Corrie A.M.

    2015-01-01

    Background and purpose: We previously found considerable variation in information provision on preoperative radiotherapy (PRT) in rectal cancer. Our aims were to reach consensus among patients and oncologists on which benefits/harms of PRT should be addressed during the consultation, and to assess congruence with daily clinical practice. Materials and methods: A four-round Delphi-study was conducted with two expert panels: (1) 31 treated rectal cancer patients and (2) 35 radiation oncologists. Thirty-seven possible benefits/harms were shown. Participants indicated whether addressing the benefit/harm was (1) essential, (2) desired, (3) not necessary, or (4) to be avoided. Consensus was assumed when ⩾80% of the panel agreed. Results were compared to 81 audio-taped consultations. Results: The panels reached consensus that six topics should be addressed in all patients (local control, survival, long term altered defecation pattern and faecal incontinence, perineal wound healing problems, advice to avoid pregnancy), three in male patients (erectile dysfunction, ejaculation disorder, infertility), and four in female patients (vaginal dryness, pain during intercourse, menopause, infertility). On average, less than half of these topics were addressed in daily clinical practice. Conclusions: This study showed substantial overlap between benefits/harms that patients and oncologists consider important to address during the consultation, and at the same time poor congruence with daily clinical practice

  3. Which benefits and harms of preoperative radiotherapy should be addressed? A Delphi consensus study among rectal cancer patients and radiation oncologists.

    Science.gov (United States)

    Kunneman, Marleen; Pieterse, Arwen H; Stiggelbout, Anne M; Marijnen, Corrie A M

    2015-02-01

    We previously found considerable variation in information provision on preoperative radiotherapy (PRT) in rectal cancer. Our aims were to reach consensus among patients and oncologists on which benefits/harms of PRT should be addressed during the consultation, and to assess congruence with daily clinical practice. A four-round Delphi-study was conducted with two expert panels: (1) 31 treated rectal cancer patients and (2) 35 radiation oncologists. Thirty-seven possible benefits/harms were shown. Participants indicated whether addressing the benefit/harm was (1) essential, (2) desired, (3) not necessary, or (4) to be avoided. Consensus was assumed when ⩾80% of the panel agreed. Results were compared to 81 audio-taped consultations. The panels reached consensus that six topics should be addressed in all patients (local control, survival, long term altered defecation pattern and faecal incontinence, perineal wound healing problems, advice to avoid pregnancy), three in male patients (erectile dysfunction, ejaculation disorder, infertility), and four in female patients (vaginal dryness, pain during intercourse, menopause, infertility). On average, less than half of these topics were addressed in daily clinical practice. This study showed substantial overlap between benefits/harms that patients and oncologists consider important to address during the consultation, and at the same time poor congruence with daily clinical practice. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  4. BIOLOGICAL EFFECTS OF MICROWAVE RADIATION ON BRAIN TISSUE IN RATS

    Directory of Open Access Journals (Sweden)

    Boris Đinđić

    2003-04-01

    Full Text Available Exposure to microwave radiation induces multiple organ dysfunctions, especially in CNS.The aim of this work was investigation of biological effects of microwave radiation on rats' brain and determination of increased oxidative stress as a possible pathogenetic's mechanism.Wis tar rats 3 months old were divided in experimental (4 female and 4 male animal and control group (5 female and 4 male. This experimental group was constantly exposed to a magnetic field of 5 mG. We simulated using of mobile phones 30 min every day. The source of NIR emitted MF that was similar to mobile phones at 900 MHz. The rats were killed after 2 months. Biological effects were determined by observation of individual and collective behavior and body mass changes. Lipid per oxidation was determined by measuring quantity of malondialdehyde (MDA in brain homogenate.The animals in experimental group exposed to EMF showed les weight gain. The most important observations were changing of basic behavior models and expression of aggressive or panic behavior. The content of MDA in brain tissue is singificantly higher (1.42 times in rats exposed to electromagnetic fields (3,82±0.65 vs. control 2.69±0.42 nmol/mg proteins, p<0.01.Increased oxidative stress and lipid peroxidation after exposition in EM fields induced disorders of function and structure of brain.

  5. Comparative biological hazards of chemical pollutants and radiation

    International Nuclear Information System (INIS)

    Mukherjee, R.N.

    1978-01-01

    Chemical pollutants from conventional energy and industrial sources released to the environment presumably pose a hazard to man's health and environmental resources. Insufficient knowledge of their detailed mechanisms of interaction with the biological systems seems to provide the greatest drawback in current attempts for realistic assessment of the health risks of chemical pollutants in the short and long terms. Nevertheless, their detrimental health consequences are becoming more and more apparent as a result of recent epidemiological surveys of workers in conventional energy installations and of the chronically exposed general public. So far nuclear power has succeeded in achieving a remarkable health safety record. In view of its projected expansion, research on biological effects of low-level radiation and radionuclides should continue to re-evaluate the health safety consequences. However, a projection from past experiences together with continued efforts to improvements of health safety aspects seem to justify an expectation that the proposed expansions in the nuclear power programme should not have an unfavourable impact on the environment. The potential hazards and challenges from the associated radiation in man's environment have proved manageable. More attention now needs to be paid urgently to safeguard human health and environment against the chemical pollutants

  6. Radiation degradation of carbohydrates and their biological activities for plants

    International Nuclear Information System (INIS)

    Kume, T.; Nagasawa, N.; Matsuhashi, S.

    2000-01-01

    Radiation effects on carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated to improve the biological activities. These carbohydrates were easily degraded by irradiation and induced various kinds of biological activities such as anti-bacterial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction. Pectic fragments obtained from degraded pectin induced the phytoalexins such as glyceollins in soybean and pisatin in pea. The irradiated chitosan shows the higher elicitor activity for pisatin than that of pectin. For the plant growth promotion, alginate derived from brown marine algae, chitosan and ligno-cellulosic extracts show a strong activity. Kappa and iota carrageenan derived from red marine algae can promote growth of rice and the highest effect was obtained with kappa irradiated at 100 kGy. Some radiation degraded carbohydrates suppressed the damage of heavy metals on plants. The effects of irradiated carbohydrates on transportation of heavy metals have been investigated by PETIS (Positron Emitting Tracer Imaging System) and autoradiography using 48 V and 62 Zn. (author)

  7. Radiation degradation of carbohydrates and their biological activities for plants

    Energy Technology Data Exchange (ETDEWEB)

    Kume, T.; Nagasawa, N.; Matsuhashi, S. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment] [and others

    2000-03-01

    Radiation effects on carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated to improve the biological activities. These carbohydrates were easily degraded by irradiation and induced various kinds of biological activities such as anti-bacterial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction. Pectic fragments obtained from degraded pectin induced the phytoalexins such as glyceollins in soybean and pisatin in pea. The irradiated chitosan shows the higher elicitor activity for pisatin than that of pectin. For the plant growth promotion, alginate derived from brown marine algae, chitosan and ligno-cellulosic extracts show a strong activity. Kappa and iota carrageenan derived from red marine algae can promote growth of rice and the highest effect was obtained with kappa irradiated at 100 kGy. Some radiation degraded carbohydrates suppressed the damage of heavy metals on plants. The effects of irradiated carbohydrates on transportation of heavy metals have been investigated by PETIS (Positron Emitting Tracer Imaging System) and autoradiography using {sup 48}V and {sup 62}Zn. (author)

  8. Radioprotection, biological effects of the radiations and security in the handling of radioactive material

    CERN Document Server

    Teran, M

    2000-01-01

    The development of the philosophy of the radioprotection is dependent on the understanding of the effects of the radiation in the man. Behind the fact that the radiation is able to produce biological damages there are certain factors with regard to the biological effects of the radiations that determine the boarding of the radioprotection topics.

  9. Radiation physics, biophysics and radiation biology. Progress report, October 1, 1982-November 1983

    International Nuclear Information System (INIS)

    1983-07-01

    A wide range of research is carried out at the Radiological Research Laboratory, from computer simulation of particle tracks to the determination of oncogenic transformation in mammalian cells. Mechanistic studies remain the central mission in an attempt to understand the biological action of ionizing radiations. Collaborative research is carried out on the use of radiosensitizers on chemosensitizers on the effect of hormones on oncogenic transformation and on cataractogenesis

  10. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1985-November 30, 1986

    International Nuclear Information System (INIS)

    Hall, E.J.

    1986-07-01

    This is the annual report of the Radiological Research Laboratory of the Department of Radiation Oncology, Columbia University. The bulk of the research of the Laboratory involves basic and fundamental aims, not confined to radiotherapy. Research carried out in the Laboratory covers the determination of microdosimetry quantities, computer simulation of particle tracks, determination of oncogenic transformation, and the transfection of DNA into cells. The Hallmark of the Laboratory is the interaction between physics and biology

  11. Potential of biological images for radiation therapy of cancer

    International Nuclear Information System (INIS)

    Ling, C.

    2001-01-01

    Full text: Recent technical advances in 3D conformal and intensity modulated radiotherapy (3DCRT and IMRT) based, on patient-specific CT and MRI images, have the potential of delivering exquisitely conformal dose distributions to the target volume while avoiding critical structures. Emerging clinical results in terms of reducing treatment-related morbidity and increasing local control appear promising. Recent developments in imaging have suggested that biological images may further positively impact cancer diagnosis, characterization and therapy. While in the past radiological images are largely anatomical, the new types of images can provide metabolic, biochemical, physiological, functional and molecular (genotypic and phenotypic) information. For radiation therapy, images that give information about factors (e.g. tumor hypoxia, T pot ) that influence radiosensitivity and treatment outcome can be regarded as radiobiological images. The ability of IMRT to 'paint' (in 2D) or 'sculpt' (in 3D) the dose, and produce exquisitely conformal dose distributions begs the '64 million dollar question' as to how to paint or sculpt, and whether biological imaging may provide the pertinent information. Can this new approach provide 'radiobiological phenotypes' non-invasively, and incrementally improve upon the predictive assays of radiobiological characteristics such as proliferative activity (T pot - the potential doubling time), radiosensitivity (SF 2 - the surviving fraction at a dose of 2 Gy), energy status (relative to sublethal damage repair), pH (a possible surrogate of hypoxia), tumor hypoxia, etc. as prognosticator(s) of radiation treatment outcome. Important for IMRT, the spatial (geometrical) distribution of the radiobiological phenotypes provide the basis for dose distribution design to conform to both the physical (geometrical) and the biological attributes. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

  12. Health and biological effects of non-ionizing radiations

    International Nuclear Information System (INIS)

    De Seze, R.; Souques, M.; Aurengo, A.; Bach, V.; Burais, N.; Cesarini, J.P.; Cherin, A.; Decobert, V.; Dubois, G.; Hours, M.; Lagroye, I.; Leveque, Ph.; Libert, J.P.; Lombard, J.; Loos, N.; Mir, L.; Perrin, A.; Poulletier De Gannes, F.; Thuroczy, G.; Wiart, J.; Lehericy, St.; Pelletier, A.; Marc-Vergnes, J.P.; Douki, Th.; Guibal, F.; Tordjman, I.; Gaillot de Saintignon, J.; Collard, J.F.; Scoretti, R.; Magne, I.; Veyret, B.; Katrib, J.

    2011-01-01

    This document gathers the slides of the available presentations given during this conference day on the biological and health effects of non-ionizing radiations. Sixteen presentations out of 17 are assembled in the document and deal with: 1 - NMR: biological effects and implications of Directive 2004/40 on electromagnetic fields (S. Lehericy); 2 - impact of RF frequencies from mobile telephone antennas on body homeostasis (A. Pelletier); 3 - expression of stress markers in the brain and blood of rats exposed in-utero to a Wi-Fi signal (I. Lagroye); 4 - people exposure to electromagnetic waves: the challenge of variability and the contribution of statistics to dosimetry (J. Wiart); 5 - status of knowledge about electromagnetic fields hyper-sensitivity (J.P. Marc-Vergnes; 6 - geno-toxicity of UV radiation: respective impact of UVB and UVA (T. Douki); 7 - National day of prevention and screening for skin cancers (F. Guibal); 8 - UV tan devices: status of knowledge about cancer risks (I. Tordjman, and J. Gaillot de Saintignon); 9 - modulation of brain activity during a tapping task after exposure to a 3000 μT magnetic field at 60 Hz (M. Souques and A. Legros); 10 - calculation of ELF electromagnetic fields in the human body by the finite elements method (R. Scoretti); 11 - French population exposure to the 50 Hz magnetic field (I. Magne); 12 - LF and static fields, new ICNIRP recommendations: what has changed, what remains (B. Veyret); 13 - risk assessment of low energy lighting systems - DELs and CFLs (J.P. Cesarini); 14 - biological effects to the rat of a chronic exposure to high power microwaves (R. De Seze); 15 - theoretical and experimental electromagnetic compatibility approaches of active medical implants in the 10-50 Hz frequency range: the case of implantable cardiac defibrillators (J. Katrib); French physicians and electromagnetic fields (M. Souques). (J.S.)

  13. 13th AINSE radiation biology conference: conference handbook

    International Nuclear Information System (INIS)

    1991-01-01

    The forty one papers presented at this conference covered the areas of radiation induced lesions, apoptosis, genetics and radiobiological consequences of low level radiation exposure, clinical applications of radiation, mammalian cells radiosensitivity and radiation-activated proteins

  14. Continuing training program in radiation protection in biological research centers

    International Nuclear Information System (INIS)

    Escudero, R.; Hidalgo, R.M.; Usera, F.; Macias, M.T.; Mirpuri, E.; Perez, J.; Sanchez, A.

    2008-01-01

    The use of ionizing radiation in biological research has many specific characteristics. A great variety of radioisotopic techniques involve unsealed radioactive sources, and their use not only carries a risk of irradiation, but also a significant risk of contamination. Moreover, a high proportion of researchers are in training and the labor mobility rate is therefore high. Furthermore, most newly incorporated personnel have little or no previous training in radiological protection, since most academic qualifications do not include training in this discipline. In a biological research center, in addition to personnel whose work is directly associated with the radioactive facility (scientific-technical personnel, operators, supervisors), there are also groups of support personnel The use of ionizing radiation in biological research has many specific characteristics. A great variety of radioisotopic techniques involve unsealed radioactive sources, and their use not only carries a risk of irradiation, but also a significant risk of contamination. Moreover, a high proportion of researchers are in training and the labor mobility rate is therefore high. Furthermore, most newly incorporated personnel have little or no previous training in radiological protection, since most academic qualifications do not include training in this discipline. In a biological research center, in addition to personnel whose work is directly associated with the radioactive facility (scientific-technical personnel, operators, supervisors), there are also groups of support personnel maintenance and instrumentation workers, cleaners, administrative personnel, etc. who are associated with the radioactive facility indirectly. These workers are affected by the work in the radioactive facility to varying degrees, and they therefore also require information and training in radiological protection tailored to their level of interaction with the installation. The aim of this study was to design a

  15. Biology panel: coming to a clinic near you. Translational research in radiation biology

    International Nuclear Information System (INIS)

    Travis, Elizabeth L.; Thames, Howard D.

    1996-01-01

    The explosion of knowledge in molecular biology coupled with the rapid and continuing development of molecular techniques allow a new level of research in radiation biology aimed at understanding the processes that govern radiation damage and response in both tumors and normal tissues. The challenge to radiation biologists and radiation oncologists is to use this knowledge to improve the therapeutic ratio in the management of human tumors by rapidly translating these new findings into clinical practice. This panel will focus on both sides of the therapeutic ratio coin, the manipulation of tumor control by manipulating the processes that control cell cycle regulation and apoptosis, and the reduction of normal tissue morbidity by applying the emerging information on the genetic basis of radiosensitivity. Apoptosis is a form of cell death believed to represent a minor component of the clinical effects of radiation. However, if apoptosis is regulated by anti-apoptotic mechanisms, then it may be possible to produce a pro-apoptotic phenotype in the tumor cell population by modulating the balance between pro- and anti-apoptotic mechanisms by pharmacological intervention. Thus signaling-based apoptosis therapy, designed to overcome the relative resistance to radiation-induced apoptosis, may improve the therapeutic ratio in the management of human tumors. The explosion of information concerning cell cycle regulation in both normal and tumor cells has provided the opportunity for insights into the mechanism of action of chemotherapeutic agents that can act as radiosensitizers. The second talk will explore the hypothesis that the dysregulation of cell cycle checkpoints in some cancers can be exploited to improve the therapeutic index of radiation sensitizers, specifically the fluoropyrimidines which appear to act at the G1/S transition. Finally, efforts to increase tumor control will be translated into clinical practice only if such treatments do not increase the complication

  16. Biological dose assessment of 15 victims in Haerbin radiation accident

    International Nuclear Information System (INIS)

    Liu, Jian-xiang; Huang, Min-yan; Ruan, Jian-lei; Bai, Yu-shu; Xu, Su

    2008-01-01

    Full text: a) On July 5 and 8, 2005, Two patients with bone marrow suppression were successively hospitalized by the First Affiliated Hospital of Haerbin Medical University. Examination results showed that the patients seemed to get suspicious radiation disease. On July 13, 2005, a radioactive source was found in the patients' dwelling. The radiation source is Iridium-192 with 0.5 Ci(1.85 x 10 10 Bq) radioactivity. The radiation source is a metal bar which is a kind of radioactive industrial detection source for welding. The source is currently stored in the urban radioactive waste storehouse of Heilongjiang province. After finding the radioactive source on July 13, The Haerbin municipal government initiated an emergency response plan and developed medical rescue, radioactive source examination and case detection through organizing ministries involving health, environmental protection and public security. After receiving a report at 17:00 on July 14, 2005, Chinese Ministry of Health immediately sent experts to the spot for investigation, dose estimation and direction of patients' rescue. Health authority carried out physical examination twice on 113 residents within 30 meters to the source, among which 4 got radiation sickness, 5 showed abnormal hemotogram, and others showed no abnormal response. Of 4 patients with radiation sickness, one 81 year old patient has died of severe bone marrow form of sub acute radiation sickness coupled with lung infection and prostrate apparatus at 13:00 on Oct., 20. Two children have been treated in Beitaiping Road Hospital in Beijing, another patient has been treated in local hospital. b) Biological dosimetry using conventional chromosome aberration analysis in human peripheral blood lymphocytes has been shown as a reliable and useful tool in medical management of radiation accident victims. Peripheral blood lymphocytes of the victims were cultured using conventional culture medium with colchicine added at the beginning. Chromosome

  17. Radiation physics, biophysics, and radiation biology. Final report, October 1, 1971--September 30, 1977

    International Nuclear Information System (INIS)

    Rossi, H.H.; Hall, E.J.

    1978-02-01

    Research under Contract EY-76-C-02-3243 has been carried out in the area of Radiation Physics, Biophysics and Radiation Biology. During the period of this contract the major accomplishments include, in Physics, the refinement of tissue equivalent dosimetry, the formulation of the concepts of microdosimetry, the development of apparatus used in microdosimetry, and the development of ionization chambers with internal gas multiplication. Principal contributions in Radiobiology have included the determination of RBE and OER as a function of neutron energy, the study of combined effects of radiation and a variety of other agents, and the investigation of the transformation of cells in tissue culture. Theoretical research centered around the development of the theoretical framework of microdosimetry and the establishment of the Theory of Dual Radiation Action. In a cooperative effort with Brookhaven National Laboratory, a major accelerator facility dedicated exclusively to Radiobiology and Radiation Physics, has been developed. Members of the laboratory have performed extensive service to national and international organizations

  18. Low-level radiation: biological interactions, risks, and benefits. A bibliography

    International Nuclear Information System (INIS)

    1978-09-01

    The bibliography contains 3294 references that were selected from the Department of Energy's data base (EDB). The subjects covered are lower-level radiation effects on man, environmental radiation, and other biological interactions of radiation that appear to be applicable to the low-level radiation problem

  19. Low-level radiation: biological interactions, risks, and benefits. A bibliography

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-09-01

    The bibliography contains 3294 references that were selected from the Department of Energy's data base (EDB). The subjects covered are lower-level radiation effects on man, environmental radiation, and other biological interactions of radiation that appear to be applicable to the low-level radiation problem.

  20. Low Level Laser Therapy: laser radiation absorption in biological tissues

    Science.gov (United States)

    Di Giacomo, Paola; Orlando, Stefano; Dell'Ariccia, Marco; Brandimarte, Bruno

    2013-07-01

    In this paper we report the results of an experimental study in which we have measured the transmitted laser radiation through dead biological tissues of various animals (chicken, adult and young bovine, pig) in order to evaluate the maximum thickness through which the power density could still produce a reparative cellular effect. In our experiments we have utilized a pulsed laser IRL1 ISO model (based on an infrared diode GaAs, λ=904 nm) produced by BIOMEDICA s.r.l. commonly used in Low Level Laser Therapy. Some of the laser characteristics have been accurately studied and reported in this paper. The transmission results suggest that even with tissue thicknesses of several centimeters the power density is still sufficient to produce a cell reparative effect.

  1. The relative biological effectiveness of radiations of different quality

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    This paper is a review of the literature relevant to the selection of relative biological effectiveness (RBE) values for use in arriving at values of the quality factor (Q). Emphasis is placed on response to small ( M . In a wide variety of systems, the RBE M for fast (fission) neutrons, with low doses and dose rates, appears to be of the order of 20 or more compared to moderately filtered 250 kVp x rays and 40 or more compared to higher energy gamma rays. These values, which are much larger than those observed with large doses delivered at high dose rates, are due mainly, but not entirely, to a decrease in the slope of the curve for the ow-LET reference radiation at low dose

  2. Scientific projection paper on biologic effects of ionizing radiation

    International Nuclear Information System (INIS)

    Matanoski, G.

    1980-01-01

    There is widespread knowledge about the effects of radiation in human populations but the studies have had some limitations which have left gaps in our knowledge. Most populations have had exposure to high doses with little information on the effect of dose rate. The characteristics of the populations have been restricted by the location of the disaster, the occupational limitations, or the basic risks associated with the under-lying disease for which radiation was given. All doses have been estimated and such values are subject to marked variability particularly when they rely on sources of data such as hospital records. The biological data although extensive have several deficits in information. Which are the sites in which cancer is produced by irradiation and what are the cell types which are produced. The sensitivity of various tissues and organs are not similar and it is important to rank them according to susceptibility. This has been done in the past but the results are not complete for all cell types and organs. The temporal patterns for tumor development, the latent period, the period of expressed excess, the life-time risks need to be defined more precisely for the cancers. Many populations have not been followed long enough to express the complete risk

  3. Study on the radiation-induced biological responses based on the analysis of metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Sungkee; Jung, Uhee; Park, Haeran; Roh, Changhyun; Shin, Heejune; Ryu, Dongkyoung

    2013-01-15

    1. Objectives □ Establishment of basis of biological radiation response study by metabolite analysis 2. Project results □ Establishment of analytical basis of radiation-responsive metabolites in biological samples - Large scale collection of tissue samples from irradiated animal for radiation metabolomics research - Establishment of mass spectromety (GC MS, LC MS-MS) analysis methods of biological samples - 3 Standard Operation Protocols (SOP) for ultra high resolution mass spectrometry (FT-ICR MS, Q-TOF MS) analysis of metabolites from biological samples - Establishment of database for radiation metabolites □ Basic research on radiation-responsive metabolites and the interpretation of their functions - Validation of spermidine as a candidate biomarker of acute radiation response in mouse blood - Verification of 5 radiation-responsive steroid hormones and alteration of their metabolic enzyme activities in mouse blood - Verification of 13 radiation-responsive amino acids (related to oxidative stress, neurotransmission, energy metabolism) in regional mouse brain -Verification of 10 radiation-responsive amino acids (related to oxidative stress, neurotransmission, energy metabolism) in regional mouse brain - Verification of 74 radiation-responsive metabolites in whole rat brain by ultra high resolution FT-ICR MS and Q-TOF MS analysis 3. Expected benefits and plan of application □ Establishment of research basis of radiation metabolomics in Korea □ Provision of core technology in radiation bioscience and safety field by application of radiation metabolomics results to the technology development in radiation biodosimetry, and radiation response evaluation and modulation.

  4. Radiation efficacy and biological risk from whole-breast irradiation via intensity modulated radiation therapy (IMRT)

    Science.gov (United States)

    Desantis, David M.

    Radiotherapy is an established modality for women with breast cancer. During the delivery of external beam radiation to the breast, leakage, scattered x-rays from the patient and the linear accelerator also expose healthy tissues and organs outside of the breast, thereby increasing the patient's whole-body dose, which then increases the chance of developing a secondary, radiation-induced cancer. Generally, there are three IntensityModulated Radiotherapy (IMRT) delivery techniques from a conventional linear accelerator; forward planned (FMLC), inverse planned 'sliding window' (DMLC), and inverse planned 'step-and-shoot' (SMLC). The goal of this study was to determine which of these three techniques delivers an optimal dose to the breast with the least chance of causing a fatal, secondary, radiation-induced cancer. A conventional, non-IMRT, 'Wedge' plan also was compared. Computerized Tomography (CT) data sets for both a large and small sized patient were used in this study. With Varian's Eclipse AAA algorithm, the organ doses specified in the revised ICRP 60 publication were used to calculate the whole-body dose. Also, an anthropomorphic phantom was irradiated with thermoluminescent dosimeters (TLD) at each organ site for measured doses. The risk coefficient from the Biological Effects of Ionizing Radiation (BEIR) VII report of 4.69 x 10-2 deaths per Gy was used to convert whole-body dose to risk of a fatal, secondary, radiation-induced cancer. The FMLC IMRT delivered superior tumor coverage over the 3D conventional plan and the inverse DMLC or SMLC treatment plans delivered clinically equivalent tumor coverage. However, the FMLC plan had the least likelihood of inadvertently causing a fatal, secondary, radiation-induced cancer compared to the inverse DMLC, SMLC, and Wedge plans.

  5. Development of radiation biological dosimetry and treatment of radiation-induced damaged tissue

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil [and others

    2000-04-01

    Util now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline(triage) to be able to be treated the victims as fast as possible. We established the apoptotic fragment assay, PCC, comet assay, and micronucleus assay which was the significant relationship between dose and cell damages to evaluate the irradiated dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with chromosome dosimetry and micronucleus assay.

  6. Development of radiation biological dosimetry and treatment of radiation-induced damaged tissue

    International Nuclear Information System (INIS)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil

    2000-04-01

    Util now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline(triage) to be able to be treated the victims as fast as possible. We established the apoptotic fragment assay, PCC, comet assay, and micronucleus assay which was the significant relationship between dose and cell damages to evaluate the irradiated dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with chromosome dosimetry and micronucleus assay

  7. Current Status and Recommendations for the Future of Research, Teaching, and Testing in the Biological Sciences of Radiation Oncology: Report of the American Society for Radiation Oncology Cancer Biology/Radiation Biology Task Force, Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Wallner, Paul E., E-mail: pwallner@theabr.org [21st Century Oncology, LLC, and the American Board of Radiology, Bethesda, Maryland (United States); Anscher, Mitchell S. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Barker, Christopher A. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Bassetti, Michael [Department of Human Oncology, University of Wisconsin Carbone Cancer Center, Madison, Wisconsin (United States); Bristow, Robert G. [Departments of Radiation Oncology and Medical Biophysics, Princess Margaret Cancer Center/University of Toronto, Toronto, Ontario (Canada); Cha, Yong I. [Department of Radiation Oncology, Norton Cancer Center, Louisville, Kentucky (United States); Dicker, Adam P. [Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Formenti, Silvia C. [Department of Radiation Oncology, New York University, New York, New York (United States); Graves, Edward E. [Departments of Radiation Oncology and Radiology, Stanford University, Stanford, California (United States); Hahn, Stephen M. [Department of Radiation Oncology, University of Pennsylvania (United States); Hei, Tom K. [Center for Radiation Research, Columbia University, New York, New York (United States); Kimmelman, Alec C. [Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Kirsch, David G. [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Kozak, Kevin R. [Department of Human Oncology, University of Wisconsin (United States); Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan (United States); Marples, Brian [Department of Radiation Oncology, Oakland University, Oakland, California (United States); and others

    2014-01-01

    In early 2011, a dialogue was initiated within the Board of Directors (BOD) of the American Society for Radiation Oncology (ASTRO) regarding the future of the basic sciences of the specialty, primarily focused on the current state and potential future direction of basic research within radiation oncology. After consideration of the complexity of the issues involved and the precise nature of the undertaking, in August 2011, the BOD empanelled a Cancer Biology/Radiation Biology Task Force (TF). The TF was charged with developing an accurate snapshot of the current state of basic (preclinical) research in radiation oncology from the perspective of relevance to the modern clinical practice of radiation oncology as well as the education of our trainees and attending physicians in the biological sciences. The TF was further charged with making suggestions as to critical areas of biological basic research investigation that might be most likely to maintain and build further the scientific foundation and vitality of radiation oncology as an independent and vibrant medical specialty. It was not within the scope of service of the TF to consider the quality of ongoing research efforts within the broader radiation oncology space, to presume to consider their future potential, or to discourage in any way the investigators committed to areas of interest other than those targeted. The TF charge specifically precluded consideration of research issues related to technology, physics, or clinical investigations. This document represents an Executive Summary of the Task Force report.

  8. Current status and recommendations for the future of research, teaching, and testing in the biological sciences of radiation oncology: report of the American Society for Radiation Oncology Cancer Biology/Radiation Biology Task Force, executive summary.

    Science.gov (United States)

    Wallner, Paul E; Anscher, Mitchell S; Barker, Christopher A; Bassetti, Michael; Bristow, Robert G; Cha, Yong I; Dicker, Adam P; Formenti, Silvia C; Graves, Edward E; Hahn, Stephen M; Hei, Tom K; Kimmelman, Alec C; Kirsch, David G; Kozak, Kevin R; Lawrence, Theodore S; Marples, Brian; McBride, William H; Mikkelsen, Ross B; Park, Catherine C; Weidhaas, Joanne B; Zietman, Anthony L; Steinberg, Michael

    2014-01-01

    In early 2011, a dialogue was initiated within the Board of Directors (BOD) of the American Society for Radiation Oncology (ASTRO) regarding the future of the basic sciences of the specialty, primarily focused on the current state and potential future direction of basic research within radiation oncology. After consideration of the complexity of the issues involved and the precise nature of the undertaking, in August 2011, the BOD empanelled a Cancer Biology/Radiation Biology Task Force (TF). The TF was charged with developing an accurate snapshot of the current state of basic (preclinical) research in radiation oncology from the perspective of relevance to the modern clinical practice of radiation oncology as well as the education of our trainees and attending physicians in the biological sciences. The TF was further charged with making suggestions as to critical areas of biological basic research investigation that might be most likely to maintain and build further the scientific foundation and vitality of radiation oncology as an independent and vibrant medical specialty. It was not within the scope of service of the TF to consider the quality of ongoing research efforts within the broader radiation oncology space, to presume to consider their future potential, or to discourage in any way the investigators committed to areas of interest other than those targeted. The TF charge specifically precluded consideration of research issues related to technology, physics, or clinical investigations. This document represents an Executive Summary of the Task Force report. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Biological and sanitary effects of non ionizing radiations

    International Nuclear Information System (INIS)

    Brugere, H.; Hours, M.; Seze, R. de; Bernier, M.; Letertre, Th.; Aurengo, A.; Burais, N.; Bedja, M.; Merckel, O.; Decat, G.; Lagroye, I.; Perrin, A.; Poulletier de Gannes, F.; Aurengo, A.; Souques, M.; Cesarini, J.P.; Lagroye, I.; Aurengo, A.; Cesarini, J.P.

    2008-01-01

    The objective of this day was to encourage the collaborations, especially multidisciplinary, on the biological, clinical, epidemiological and dosimetry aspects. The different presentations are as follow: the magneto reception among animals; the health and radio frequencies foundation; expo-metry to radio frequency fields: dosemeters evaluation; the electro-optical probes as tool of hyper frequency dosimetry; characterisation of emissions produced by the low consumption fluo-compact lamps in the perspective of persons exposure; strong and weak points of epidemiology; numerical dosimetry in low frequency magnetic and/or electric field; exposure of the French population to the 50 Hz magnetic field: first results for the Ile-de-france and Rhone alpes areas; characterisation of the exposure to the very low frequency magnetic fields in the town of Champlan; measurement of the residential exposure of children to the extremely low frequency, very low frequency and radiofrequency (E.L.F., V.L.F. and R.F.) fields and modeling of the high voltage magnetic field face to the child leukemia; effects of radiofrequency signals of wireless communications on the young animals; study of combined effects of 2.45 GHz microwaves and a known mutagen on DNA by two different approaches; effects on the oxidizing stress of nervous cells exposure to an (enhanced data rates for GSM evolution) E.D.G.E. signal; is environmental epidemiology still a science; cardiac implants and exposure to 50 Hz electromagnetic fields in occupational environment; the tanning by artificial UV radiation: norms and legislation; mobiles phones, Wi Fi and other wireless communications; effects on health of 50-60 Hz electromagnetic fields; natural and artificial ultraviolet radiations: a proved risk. (N.C.)

  10. Biological dosimetry by the radiation effects on the skin

    International Nuclear Information System (INIS)

    Bessho, Yuko

    1994-01-01

    In cases of partial body over-exposure, the dose estimation with personal monitors or with reconstruction of exposed conditions is often impossible without considerable error. Clinical signs of irradiated skin, such as epilation or moist desquamation have been used as the indicators of doses in the radiological accidents, because each sign has the threshold dose. As hair growth is known to be sensitive to radiation, the dose-effect relationship of the delay of hair regrowth and the reduction in hair length of mice after irradiation were examined to investigate if they can be used as biological dosimeters. Hairs on the dorsal skin of 290 ICR mice (8 weeks old) were shaved and irradiated with a Sr-90/Y-90 β-ray source in the early anagen and the midanagen stages of the hair cycle. Skin doses were from 0.5 to 10 Gy. The time of hair regrowth and the hair length were examined with the scaling loupe. Dose-effect relationship of the delay of hair regrowth and reduction in hair length were both clearly dose dependent, fitting the L-Q or L function depending on the stage. Dose estimation functions were derived from the dose-effect relationship curves. The histological observations suggested that hair growth retardation caused by irradiation in midanagen might be due to the cell death and the depression of mitosis in the hair matrix cells. This dose estimation method was applied to the case who was over-exposed to X-ray on his hand and fingers. The findings showed that hair regrowth delay was a sensitive biological dosimeter in the case of partial body over-exposure, which could be applied as early as a few days after over-exposure. The method was simple and non-invasive to the exposed patient. (author)

  11. Influence of vitamins on cytostatic drugs: radiation-chemical and radiation-biological investigations in vitro

    International Nuclear Information System (INIS)

    Heinrich, E.

    2002-03-01

    Many environmental burdens (air pollution, formation of ozone etc.), humans nowadays are exposed to, in connection with unhealthy way of living promote the formation of free radicals e.g. OH and peroxylradicals in the organism. Those show an enormous cell-damaging effect, and can weaken the immune system or cause cancer diseases. The number of humans suffering from different forms of cancer is rising world-wide. Therefore it is necessary to find new and better therapy forms for this illness. The organism has its own protective system, which is able to capture free radicals and make them innocuous to a large extent. Apart from various enzyme systems the antioxidizing vitamins C (ascorbic acid), E (α-tocopherol) and β-carotin play an important role in this process. Now it was of interest whether vitamin B1 (thiamine) also possesses the ability to work as a radiation protector or to influence the effect of different cytostatic drugs. In the context of this thesis the radiation-chemical and radiation-biological behaviour of vitamin B1 was examined under different conditions (in presence and absence of oxygen as well as in media saturated with N 2 O). HPLC analysis were performed to establish radiolysis products. Furthermore the synergistic effect of vitamin B1 on cytostatic drugs (sanazole, mitomycin C) was studied alone or in combination with other vitamins (C, E and β-carotin) by using two different E. coli bacteria strains as a model for living systems. (author)

  12. Molecular biology in radiation oncology. Radiation oncology perspective of BRCA1 and BRCA2

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, C.N. [Harvard Medical School (United States). Joint Center for Radiation Therapy

    1999-07-01

    The breast cancer susceptibility genes, BRCA1 and BRCA2, are used to illustrate the application of molecular biology to clinical radiation oncology. Identified by linkage analysis and cloned, the structure of the genes and the numerous mutations are determined by molecular biology techniques that examine the structure of the DNA and the proteins made by the normal and mutant alleles. Mutations in the non-transcribed portion of the gene will not be found in protein structure assays and may be important in gene function. In addition to potential deleterious mutations, normal polymorphisms of the gene will also be detected, therefore not all differences in gene sequence may represent important mutations, a finding that complicates genetic screening and counseling. The localization of the protein in the nucleus, the expression in relation to cell cycle and the association with RAD51 led to the discovery that the two BRCA genes may be involved in transcriptional regulation and DNA repair. The defect in DNA repair can increase radiosensitivity which might improve local control using breast-conserving treatment in a tumor which is homozygous for the loss of the gene (i.e., BRCA1 and BRCA2 are tumor suppressor genes). This is supported by the early reports of a high rate of local control with breast-conserving therapy. Nonetheless, this radiosensitivity theoretically may also lead to increased susceptibility to carcinogenic effects in surviving cells, a finding that might not be observed for decades. The susceptibility to radiation-induced DNA damage appears also to make the cells more sensitive to chemotherapy. Understanding the role of the normal BRCA genes in DNA repair might help define a novel mechanism for radiation sensitization by interfering with the normal gene function using a variety of molecular or biochemical therapies.

  13. Study on the biological effect of cosmic radiation and the development of radiation protection technology (L-11)

    Science.gov (United States)

    Nagaoka, Shunji

    1993-01-01

    NASDA is now participating in a series of flight experiments on Spacelab missions. The first experiment was carried out on the first International Microgravity Laboratory Mission (IML-1) January 1992, and the second experiment will be conducted on the Spacelab-J Mission, First Materials Processing Test (FMPT). The equipment or Radiation Monitoring Container Devices (RMCD) includes passive dosimeter systems and biological specimens. The experiments using this hardware are designed by NASDA to measure and investigate the radiation levels inside spacecraft like space shuttle and to look at the basic effects of the space environment from the aspect of radiation biology. The data gathered will be analyzed to understand the details of biological effects as well as the physical nature of space radiation registered in the sensitive Solid-State Track Detectors (SSTD).

  14. Towards biologically conformal radiation therapy (BCRT): Selective IMRT dose escalation under the guidance of spatial biology distribution

    International Nuclear Information System (INIS)

    Yang Yong; Xing Lei

    2005-01-01

    It is well known that the spatial biology distribution (e.g., clonogen density, radiosensitivity, tumor proliferation rate, functional importance) in most tumors and sensitive structures is heterogeneous. Recent progress in biological imaging is making the mapping of this distribution increasingly possible. The purpose of this work is to establish a theoretical framework to quantitatively incorporate the spatial biology data into intensity modulated radiation therapy (IMRT) inverse planning. In order to implement this, we first derive a general formula for determining the desired dose to each tumor voxel for a known biology distribution of the tumor based on a linear-quadratic model. The desired target dose distribution is then used as the prescription for inverse planning. An objective function with the voxel-dependent prescription is constructed with incorporation of the nonuniform dose prescription. The functional unit density distribution in a sensitive structure is also considered phenomenologically when constructing the objective function. Two cases with different hypothetical biology distributions are used to illustrate the new inverse planning formalism. For comparison, treatments with a few uniform dose prescriptions and a simultaneous integrated boost are also planned. The biological indices, tumor control probability (TCP) and normal tissue complication probability (NTCP), are calculated for both types of plans and the superiority of the proposed technique over the conventional dose escalation scheme is demonstrated. Our calculations revealed that it is technically feasible to produce deliberately nonuniform dose distributions with consideration of biological information. Compared with the conventional dose escalation schemes, the new technique is capable of generating biologically conformal IMRT plans that significantly improve the TCP while reducing or keeping the NTCPs at their current levels. Biologically conformal radiation therapy (BCRT

  15. The need for and the importance of biological indicators of radiation effects with special reference to injuries in radiation accidents

    International Nuclear Information System (INIS)

    Koeteles, G.J.; Bianco, A.

    1982-01-01

    The need for further research on the existing and new biological indicators of radiation injury has been expressed. The studies on the radiation-induced alterations of membrane structure and function stimulated investigations aiming to develop an indicator based on membrane-phenomena. The co-ordinated research programme on ''Cell Membrane Probes as Biological Indicators of Radiation Injury in Radiation Accidents'' was initiated in mid 1977 and terminated in 1980. Within this programme many basic observations were made in connection with altered features of various animal and human cell membranes. Molecular, biophysical, biochemical and cell biological approaches were performed. The rapid reaction within minutes or hours of membranes against relatively low doses of various types of irradiations were described and the effects proved to be transitory, i.e. membrane regeneration occurred within hours. These dose- and timedependent alterations suggest the possibility of developing a biological indicator which would give signals at the earliest period after radiation injury when no other biological informations are available. The importance of a system of biological indicators is emphasized. (author)

  16. Cytogenetic techniques as biological indicator and dosimeter of radiation damage

    International Nuclear Information System (INIS)

    Hadjidekova, V.; Hristova, R.

    2006-01-01

    Full text: The cytogenetic methods are established techniques for bio monitoring and bio dosimetry of professionally and accidentally exposed to ionizing radiation subjects. They are applied to continue the evaluation of the physical dosimetry and to consider the individual radiosensitivity. The results of cytogenetic monitoring and dosimetry of radiation exposed subjects carried out during the last 5 years in laboratory of Radiation Genetics, NCRRP is reported. Laboratory of Radiation genetics performs cytogenetic monitoring of low dose radiation professionally or medically exposed subjects: workers in Kozloduy NPP, radioactive waste repository workers, X-rays diagnostically exposed patients, and radiotherapy exposed as well. Three cytogenetic indicators are applied as the most sensitive indicators for human radiation exposure: analysis of micronuclei (MN), chromosomal aberrations (CA) and stable translocations (FISH). The optimized methodology for application of different cytogenetic techniques for radiation estimation is discussed

  17. The radiation biology of Boron Neutron Capture Therapy

    International Nuclear Information System (INIS)

    Coderre, J.A.

    2003-01-01

    Boron Neutron Capture Therapy (BNCT) produces a complex mixture of high and low-LET radiations in tissue. Using data on the biological effectiveness of these various dose components, derived primarily in small animals irradiated with thermal neutrons, it has been possible to express clinical BNCT doses in photon-equivalent units. The accuracy of these calculated doses in normal tissue and tumor will be reviewed. Clinical trials are underway at a number of centers. There are differences in the neutron beams at these centers, and differences in the details of the clinical protocols. Ideally, data from all centers using similar boron compounds and treatment protocols should be compared and combined, if appropriate, in a multi-institutional study in order to strengthen statistical analysis. An international dosimetry exchange is underway that will allow the physical doses from the various treatment centers to be quantitatively compared. As a first step towards the comparison of the clinical data, the normal brain tolerance data from the patients treated in the initial Brookhaven National Laboratory and the Harvard/MIT BNCT clinical trials have been compared. The data provide a good estimate of the normal brain tolerance for a somnolence syndrome endpoint, and provide guidance for setting normal brain tolerance limits in ongoing and future clinical trials. Escalation of the dose in BNCT can be accomplished by increasing the amount of the boron compound administered, increasing the duration of the neutron exposure, or both. The dose escalations that have been carried out to date at the various treatment centers will be compared and contrasted. Possible future clinical trials using BNCT in combination with other modalities will be discussed

  18. Reproductive biology of the great capricorn beetle, Cerambyx cerdo (Coleoptera: Cerambycidae): a protected but occasionally harmful species.

    Science.gov (United States)

    Torres-Vila, L M

    2017-12-01

    Cerambyx cerdo (Cc) is a protected saproxylic beetle in Europe, although it is increasingly reported as an oak 'pest'. Cc ecological features are relatively well known, but, its reproductive biology is still poorly understood. Hence, we investigated the reproductive traits of Cc under laboratory conditions. In females, body length was 44.1 ± 0.9 mm, 28-53 (mean ± SE, range); fecundity 143 ± 11 eggs, 33-347; fertility 78 ± 1%, 65-93; oviposition period 44 ± 3 days, 13-128 and longevity 59 ± 5 days, 16-157. Fecundity was positively correlated with female size, longevity and oviposition period. Daily fecundity was 3.5 ± 0.2 eggs/day, 0.9-6.5 showing a fluctuating synovigenic pattern with a slight decreasing trend over time. Egg length was 3.74 ± 0.01 mm, 2.3-6.0 and egg volume 5.45 ± 0.04 mm3, 2.4-9.6. Egg size was correlated with female size, but, the relative size of eggs was larger in smaller females. Incubation time was 13.5 ± 0.1 days, 7-28. Hatching was superior in larger eggs and neonate size was positively correlated to egg volume. Females were polyandrous (up to 19 matings), but, multiple mating did not enhance fecundity or fertility. In males, body length was 41.8 ± 0.8 mm, 29-53 and longevity 49 ± 3 days, 9-124. Male longevity was unrelated to body size. Males were polygynous (up to 16 matings) and mating number did not affect male longevity. Overall, females were larger and lived longer than males. Cc reproductive traits are compared with those other Cerambycidae, especially with the congeneric pest Cerambyx welensii. Our data may be valuable to improve the protection/management measures of Cc in dehesa woodlands and other oak forests.

  19. Confronting actual influence of radiation on human bodies and biological defense mechanism

    International Nuclear Information System (INIS)

    Matsubara, Junko

    2012-01-01

    After the accident at Fukushima Daiichi Nuclear Power Plant of Tokyo Electric Power Company, social, economical, psychological pressures on local residents and fears of radiation among the general public have not been resolved. Based on the assumption that the negligence of specialists to clearly explain the influence of radiation on human bodies to the general public is the factor for above mentioned pressures and fears, the influence of radiation from a realistic view was discussed. The topics covered are: (1) understanding the meaning of radiation regulation, (2) radiation and threshold values, (3) actual influence of low-dose radiation, (4) chemical and biological defense in defense mechanism against radiation, (5) problems raised by Fukushima Daiichi nuclear accident. Furthermore, the article explains the principles and the applications of biological defense function activation, and suggested that self-help efforts to fight against stress are from now on. (S.K.)

  20. Radiations from GSM Base Stations and its Biological Effects

    African Journals Online (AJOL)

    Michael Horsfall

    0.05) higher than the RF radiations (59mV/m) in the control stations where no base stations were located within 300m radius. Comparison of these values to the International. Commission on Non-Ionizing Radiation Protection. (ICNIRP) guideline ...

  1. Radiation damage with biological specimens and organic materials

    International Nuclear Information System (INIS)

    Glaeser, R.M.

    1979-01-01

    The radiation damage referred to in this chapter is defined as any changes in the physical structure or chemical makeup of the specimen which occur as a result of exposure to the electron beam. Radiation damage occurs in organic materials predominantly as a consequence of inelastic scattering of the incident electrons which frequently results in molecular ionization and radiolysis. Other types of radiation damage which can occur are specimen etching, which occurs as the result of synergistic action of electron irradiation and the presence of certain residual gasses, and specimen heating which occurs only at electron current densities that are large on the scale of ionization damage. The primary events in radiation physics and radiation chemistry and signal-to-noise considerations are also discussed in some detail

  2. Epidemiology Without Biology: False Paradigms, Unfounded Assumptions, and Specious Statistics in Radiation Science (with Commentaries by Inge Schmitz-Feuerhake and Christopher Busby and a Reply by the Authors).

    Science.gov (United States)

    Sacks, Bill; Meyerson, Gregory; Siegel, Jeffry A

    Radiation science is dominated by a paradigm based on an assumption without empirical foundation. Known as the linear no-threshold (LNT) hypothesis, it holds that all ionizing radiation is harmful no matter how low the dose or dose rate. Epidemiological studies that claim to confirm LNT either neglect experimental and/or observational discoveries at the cellular, tissue, and organismal levels, or mention them only to distort or dismiss them. The appearance of validity in these studies rests on circular reasoning, cherry picking, faulty experimental design, and/or misleading inferences from weak statistical evidence. In contrast, studies based on biological discoveries demonstrate the reality of hormesis: the stimulation of biological responses that defend the organism against damage from environmental agents. Normal metabolic processes are far more damaging than all but the most extreme exposures to radiation. However, evolution has provided all extant plants and animals with defenses that repair such damage or remove the damaged cells, conferring on the organism even greater ability to defend against subsequent damage. Editors of medical journals now admit that perhaps half of the scientific literature may be untrue. Radiation science falls into that category. Belief in LNT informs the practice of radiology, radiation regulatory policies, and popular culture through the media. The result is mass radiophobia and harmful outcomes, including forced relocations of populations near nuclear power plant accidents, reluctance to avail oneself of needed medical imaging studies, and aversion to nuclear energy-all unwarranted and all harmful to millions of people.

  3. A Model for Protective Behavior Against the Harmful Effects of Radiation for Radiological Technologists in Medical Radiological Technologists in Medical Centers

    International Nuclear Information System (INIS)

    Han, Eun Ok; Moon, In Ok

    2009-01-01

    Protective behavior of radiological technologists against radiation exposure is important to achieve reduction of the patient doses without compromising medical achievements. This study attempts to provide a basic model for the sophisticated intervention strategy that increases the level of the protective behavior of the technologists. The model was applied to real situations in Korea to demonstrate its utility. The results of this study are summarized as follows: First, the protective environment showed the highest relationship in the factors considered, r=0.637 (p<0.01). Secondly, the important factors were protective environment in environment characteristics, expectation for the protective behavior 0.228 (p<0.001), self efficacy 0.142 (p<0.001), and attitude for the protective behavior 0.178 (p<0.001) in personal characteristics, and daily patient -0.112 (p<0.001) and number of the participation in the education session for the protective behavior 0.074 (p<0.05). Thirdly, the final protective behavior model by a path analysis method had direct influence on the attitude 0.171 (p<0.01) and environment 0.405 (p<0.01) for the protective behavior, self efficacy 0.122 (p<0.01), expectation for the protective behavior 0.16 (p<0.01), and self-efficacy in the specialty of projects 0.154 (p<0.01). The acceptance of the model determined by the absolute fit index (GFI), 0.969, and by the incremental fit index (CFI), 0.943, showed very significant levels. Value of 2/df that is a factor applied to verify the acceptance of the model was 37, which implies that the result can be accepted in the desirable range. In addition, the parsimonious fit index configured by AGFI (0.890) and TLI (0.852) was also considered as a scale that accepts the model in practical applications. In case of the establishment of some specific intervention strategies based on the protective behavior model against harmful radiation effects proposed in this study, the strategy will provide an effective way

  4. A Model for Protective Behavior Against the Harmful Effects of Radiation for Radiological Technologists in Medical Radiological Technologists in Medical Centers

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Ok [Daegu Health College, Daegu (Korea, Republic of); Moon, In Ok [Ewha Woman' s University, Seoul (Korea, Republic of)

    2009-09-15

    Protective behavior of radiological technologists against radiation exposure is important to achieve reduction of the patient doses without compromising medical achievements. This study attempts to provide a basic model for the sophisticated intervention strategy that increases the level of the protective behavior of the technologists. The model was applied to real situations in Korea to demonstrate its utility. The results of this study are summarized as follows: First, the protective environment showed the highest relationship in the factors considered, r=0.637 (p<0.01). Secondly, the important factors were protective environment in environment characteristics, expectation for the protective behavior 0.228 (p<0.001), self efficacy 0.142 (p<0.001), and attitude for the protective behavior 0.178 (p<0.001) in personal characteristics, and daily patient -0.112 (p<0.001) and number of the participation in the education session for the protective behavior 0.074 (p<0.05). Thirdly, the final protective behavior model by a path analysis method had direct influence on the attitude 0.171 (p<0.01) and environment 0.405 (p<0.01) for the protective behavior, self efficacy 0.122 (p<0.01), expectation for the protective behavior 0.16 (p<0.01), and self-efficacy in the specialty of projects 0.154 (p<0.01). The acceptance of the model determined by the absolute fit index (GFI), 0.969, and by the incremental fit index (CFI), 0.943, showed very significant levels. Value of 2/df that is a factor applied to verify the acceptance of the model was 37, which implies that the result can be accepted in the desirable range. In addition, the parsimonious fit index configured by AGFI (0.890) and TLI (0.852) was also considered as a scale that accepts the model in practical applications. In case of the establishment of some specific intervention strategies based on the protective behavior model against harmful radiation effects proposed in this study, the strategy will provide an effective way

  5. Radiation physics and biology: Progress report for period December 1, 1986-November 30, 1987

    International Nuclear Information System (INIS)

    Rubin, J.S.

    1987-04-01

    This annual report describes progress made on 14 individual research projects. These projects fall naturally into theoretical biophysics, experimental microdosimetry and radiation biology. Each project has been separately abstracted for the Energy Data Base

  6. Life sciences: Nuclear medicine, radiation biology, medical physics, 1980-1994. International Atomic Energy Agency Publications

    International Nuclear Information System (INIS)

    1994-11-01

    The catalogue lists all sales publications of the IAEA dealing with Life Sciences issued during the period 1980-1994. The publications are grouped in the following chapters: Nuclear Medicine (including Radiopharmaceuticals), Radiation Biology and Medical Physics (including Dosimetry)

  7. Treatment of Radiation Induced Biological Changes by Bone Marrow Transplantation

    International Nuclear Information System (INIS)

    El-Missiry, M.A.; Shehata, G.; Roushdy, H.M; Fayed, Th.A.

    1999-01-01

    Preventing the propagation of radiation induced oxidative damage has been a subject of considerable investigations. The ultimate goal of the present study is to use bone marrow cells to ameliorate or to treat the radiation sickness. Transplantation of bone marrow cell has shown promising results in the present experimental radiation treatment. In this report, suspension of bone marrow cells was injected into rats 12 h. after exposure to 4.5 Gy whole body gamma irradiation. Significant results were recorded on the successful control of the radiation induced disorders in a number of biochemical parameters including certain enzymatic and nonenzymatic antioxidants (superoxide dismutase and glutathione) and certain parameters related to kidney function including creatinine, urea as well as Atpase Activity in blood serum, urine and kidney tissue

  8. Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

    International Nuclear Information System (INIS)

    1997-11-01

    The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference

  9. Exposures at low doses and biological effects of ionizing radiations

    International Nuclear Information System (INIS)

    Masse, R.

    2000-01-01

    Everyone is exposed to radiation from natural, man-made and medical sources, and world-wide average annual exposure can be set at about 3.5 mSv. Exposure to natural sources is characterised by very large fluctuations, not excluding a range covering two orders of magnitude. Millions of inhabitants are continuously exposed to external doses as high as 10 mSv per year, delivered at low dose rates, very few workers are exposed above the legal limit of 50 mSv/year, and referring to accidental exposures, only 5% of the 116 000 people evacuated following the Chernobyl disaster encountered doses above 100 mSv. Epidemiological survey of accidentally, occupationally or medically exposed groups have revealed radio-induced cancers, mostly following high dose-rate exposure levels, only above 100 mSv. Risk coefficients were derived from these studies and projected into linear models of risk (linear non-threshold hypothesis: LNT), for the purpose of risk management following exposures at low doses and low dose-rates. The legitimacy of this approach has been questioned, by the Academy of sciences and the Academy of medicine in France, arguing: that LNT was not supported by Hiroshima and Nagasaki studies when neutron dose was revisited; that linear modelling failed to explain why so many site-related cancers were obviously nonlinearly related to the dose, and especially when theory predicted they ought to be; that no evidence could be found of radio-induced cancers related to natural exposures or to low exposures at the work place; and that no evidence of genetic disease could be shown from any of the exposed groups. Arguments were provided from cellular and molecular biology helping to solve this issue, all resulting in dismissing the LNT hypothesis. These arguments included: different mechanisms of DNA repair at high and low dose rate; influence of inducible stress responses modifying mutagenesis and lethality; bystander effects allowing it to be considered that individual

  10. Biological fingerprint of high LET radiation. Brenner hypothesis

    International Nuclear Information System (INIS)

    Kodama, Yoshiaki; Awa, Akio; Nakamura, Nori

    1997-01-01

    Hypothesis by Brenner et al. (1994) that in chromosome aberrations in human peripheral lymphocytes induced by radiation exposure, F value (dicentrics/rings) differs dependently on the LET and can be a biomarker of high LET radiation like neutron and α-ray was reviewed and evaluated as follows. Radiation and chromosome aberrations; in this section, unstable aberrations like dicentric and rings (r) and stable ones like translocation and pericentric inversions were described. F value. Brenner hypothesis. Bauchinger's refutation. F value determined by FISH method; here, FISH is fluorescence in situ hybridization. F value in studies by author's Radiation Effect Research Facility. Frequency of chromosome aberration in A-bomb survivors and ESR (ESR: electron spin resonance). The cause for fluctuation of F values. The Brenner hypothesis could not be supported by studies by author's facility, suggesting that the rate of inter-chromosomal and intra-chromosomal exchange abnormalities can not be distinguishable by the radiation LET. This might be derived from the difference in detection technology of r rather than in LET. (K.H.)

  11. Somatic cell genetics and the radiation biology of mammalian cells

    International Nuclear Information System (INIS)

    Puck, T.T.

    1984-01-01

    Early application of somatic cell genetics to mammalian cell radiobiology provided a definitive measurement of the mean lethal dose of ionizing radiation for mammalian cells and re-defined cellular radiosensitivity in a quantitative fashion with important implications in radiotherapy. These studies demonstrated that the killing of mammalian cells by ionizing radiation is due to damage to the DNA. They first established the fundamental role of cell turnover in determining some of the major pathological effects of the mammalian radiation syndrome. They made possible production and study of many kinds of mutant and hybrid cells including radiation-repair deficient mutants. Methods of genetic-biochemical analysis of mutants and hybrids have been devised which make possible identification of specific metabolic effects resulting from irradiation and similar actions. These studies have demonstrated that X-irradiated cells can be used as feeder layers for nourishing other cells dependent on specific cell-cell interactions for their growth. More recently, new applications have provided improved detection and quantitation of effects of low levels of radiation and other mutagens, and have made possible fine structure mapping of human genes

  12. Progress in hprt mutation assay and its application in radiation biology

    International Nuclear Information System (INIS)

    He Jing; Li Qiang

    2008-01-01

    hprt gene is an X-linked locus that has been well studied and widely used as a bio-marker in mutation detection, hprt mutation assay is a gene mutation test system in mammalian cells in vitro which has been used as a biological dosimeter. In this paper, the biological characteristics of hprt gene, hprt mutation detection methodology and the application of hprt mutation assay in radiation biology are comprehensively reviewed. (authors)

  13. The role of ionizing radiation in biological control of agricultural pests

    International Nuclear Information System (INIS)

    Mansour, M.

    2011-01-01

    Although the commercial biological control industry is growing, it still represents only a small portion of the international market of pest control sales (about 3%). This low ratio is due to several factors including high cost of production of biological control agents and technical and regulatory difficulties that complicate the shipping procedures and create trade barriers. This article summarizes the role of ionizing radiation in supporting the use of biological control agents in insect pest control and concentrates on its role in the production, transport, distribution, and release of parasites and predators and the advantages that ionizing radiation can offer, in comparison with traditional techniques. (author)

  14. Long-term biological effects induced by ionizing radiation--implications for dose mediated risk.

    Science.gov (United States)

    Miron, S D; Astărăstoae, V

    2014-01-01

    Ionizing radiations are considered to be risk agents that are responsible for the effects on interaction with living matter. The occurring biological effects are due to various factors such as: dose, type of radiation, exposure time, type of biological tissue, health condition and the age of the person exposed. The mechanisms involved in the direct modifications of nuclear DNA and mitochondrial DNA are reviewed. Classical target theory of energy deposition in the nucleus that causes DNA damages, in particular DNA double-strand breaks and that explanation of the biological consequences of ionizing radiation exposure is a paradigm in radiobiology. Recent experimental evidences have demonstrated the existence of a molecular mechanism that explains the non-targeted effects of ionizing radiation exposure. Among these novel data, genomic instability and a variety of bystander effects are discussed here. Those bystander effects of ionizing radiation are fulfilled by cellular communication systems that give rise to non-targeted effects in the neighboring non irradiated cells. This paper provides also a commentary on the synergistic effects induced by the co-exposures to ionizing radiation and various physical agents such as electromagnetic fields and the co-exposures to ionizing radiation and chemical environmental contaminants such as metals. The biological effects of multiple stressors on genomic instability and bystander effects are also discussed. Moreover, a brief presentation of the methods used to characterize cyto- and genotoxic damages is offered.

  15. Introduction to the special issue on molecular imaging in radiation biology.

    Science.gov (United States)

    Humm, John L; Dewhirst, Mark W; Bhujwalla, Zaver M

    2012-04-01

    Molecular imaging is an evolving science that is concerned with the development of novel imaging probes and biomarkers that can be used to non-invasively image molecular and cellular processes. This special issue approaches molecular imaging in the context of radiation research, focusing on biomarkers and imaging methods that provide measurable signals that can assist in the quantification of radiation-induced effects of living systems at the physical, chemical and biological levels. The potential to image molecular changes in response to a radiation insult opens new and exciting opportunities for a more profound understanding of radiation biology, with the possibility of translation of these techniques to radiotherapy practice. This special issue brings together 14 reviews dedicated to the use of molecular imaging in the field of radiation research. The initial three reviews are introductory overviews of the key molecular imaging modalities: magnetic resonance, nuclear and optical. This is followed by 11 reviews each focusing on a specialist area within the field of radiation research. These include: hypoxia and perfusion, tissue metabolism, normal tissue injury, cell death and viability, receptor targeting and nanotechnology, reporter genes, reactive oxygen species (ROS), and biological dosimetry. Over the preceding decade, molecular imaging brought significant new advances to our understanding of every area of radiation biology. This special issue shows us these advances and points to the vibrant future of our field armed with these new capabilities.

  16. Significancy of radiation biology for basic and advanced training in radiation protection

    International Nuclear Information System (INIS)

    Neumeister, K.

    1976-02-01

    Within the scope of training in radiation protection the conveyance of radiobiological knowledge is intended to promote the understanding of radiation protection measures. The paper deals with the main aspects of the radiobiological training, the use of model tests to illustrate radiation injuries and general methodic questions of instruction. (author)

  17. 14. annual meeting of the European Society of Radiation Biology

    International Nuclear Information System (INIS)

    1978-01-01

    Under the aspect of clinical application, findings of fundamental experiments on animals and cells are reported in which highly different radiation sources and doses were used. Novel and interesting results were obtained, in particular, with the application of pions and fast neutrons in the irradiation of tumour cells. (AJ) [de

  18. Basics of Radiation Biology When Treating Hyperproliferative Benign Diseases

    Directory of Open Access Journals (Sweden)

    Franz Rödel

    2017-05-01

    Full Text Available For decades, low- and moderate-dose radiation therapy (RT has been shown to exert a beneficial therapeutic effect in a multitude of non-malignant conditions including painful degenerative muscoloskeletal and hyperproliferative disorders. Dupuytren and Ledderhose diseases are benign fibroproliferative diseases of the hand/foot with fibrotic nodules and fascial cords, which determine debilitating contractures and deformities of fingers/toes, while keloids are exuberant scar formations following burn damage, surgery, and trauma. Although RT has become an established and effective option in the management of these diseases, experimental studies to illustrate cellular composites and factors involved remain to be elucidated. More recent findings, however, indicate the involvement of radiation-sensitive targets like mitotic fibroblasts/myofibroblasts as well as inflammatory cells. Radiation-related molecular mechanisms affecting these target cells include the production of free radicals to hamper proliferative activity and interference with growth factors and cytokines. Moreover, an impairment of activated immune cells involved in both myofibroblast proliferative and inflammatory processes may further contribute to the clinical effects. We here aim at briefly describing mechanisms contributing to a modulation of proliferative and inflammatory processes and to summarize current concepts of treating hyperproliferative diseases by low and moderate doses of ionizing radiation.

  19. 4. Berder Meeting - Biology of ionizing radiation - Booklet

    International Nuclear Information System (INIS)

    2013-01-01

    This conference has been organized around 5 sessions: 1) radioimmunotherapy and signaling, 2) external radiotherapy and signaling, 3) dosimetry and radiobiology, 4) early events induced by radiation, and 5) radiotherapy and tumor response. This document gathers 50 short papers the 2 first are dedicated respectively to the presentation of the 'Canceropole Grand Ouest' and the story of radioimmunotherapy

  20. Radiation protection in biological investigation centers. Problematic, development and perspectives

    International Nuclear Information System (INIS)

    Macias, M.T.; Pina, R.; Usera, F.

    1998-01-01

    The radiological risk derivatives from the radioisotope techniques accomplished in the different investigation lines developed in the Centers object of this work, have necessary made establishing an organization that assure some adequate protection conditions in the use of the ionizing radiations

  1. Effect of Infrared Laser Radiation on Biological Systems.

    Science.gov (United States)

    1973-06-01

    Streptococcus faecium . The deactivation obtained in 60 seconds in the CO2 beam was the equivalent to that produced by a radiation dose of 2.5 M rad...laser pulse of the order of 10-2 seconds duration if all the energy absorbed were taken up by specific vibrational modes of the irradiated molecules

  2. Radiation and cancer in Wales. The biological consequences of low-level radiation

    International Nuclear Information System (INIS)

    Busby, C.C.

    1994-01-01

    recent developments have made necessary the revision of the original booklet. Chapter 1 of this second edition is an updating of the first edition. Chapter 2 covers in more detail the effects of low-level radiation in Wales, including discussion of the increases in bone cancer and the effects of Chernobyl. The second-event theory is reproduced as Chapter 3, which also includes a copy of the original paper to the International Journal of Radiation Biology and some of the responses which have been made to it, both by the referees for this journal and other authorities in the field

  3. [The indicators of biological age and accelerated aging in liquidators of the consequences of radiation accidents].

    Science.gov (United States)

    Puchkova, E I; Alishev, N V

    2011-01-01

    The biological age (BA) of the majority of the liquidators of the consequences of the radiation accidents in the Navy and of the liquidators of the Chernobyl' APS accident exceeds the medium standard and the DBA (due BA). The index of the BA can be a characteristic of the influence of the social-hygienic factors on the health condition of the Special Risk Subunit--the liquidators of the consequences of the radiation accidents. It was established, that the radiation influence concerns to the factors dramatically increasing the BA and the rate of senescence of the liquidators of the consequences of the radiation accidents.

  4. Biological effectiveness and application of heavy ions in radiation therapy described by a physical and biological model

    International Nuclear Information System (INIS)

    Olsen, K.J.; Hansen, J.W.

    1982-12-01

    A description is given of the physical basis for applying track structure theory in the determination of the effectiveness of heavy-ion irradiation of single- and multi-hit target systems. It will be shown that for applying the theory to biological systems the effectiveness of heavy-ion irradiation is inadequately described by an RBE-factor, whereas the complete formulation of the probability of survival must be used, as survival depends on both radiation quality and dose. The theoretical model of track structure can be used in dose-effect calculations for neutron-, high-LET, and low-LET radiation applied simultaneously in therapy. (author)

  5. Thalassiosira mala (Bacillariophyta), a potentially harmful, marine ...

    Indian Academy of Sciences (India)

    Thalassiosira malaitalic> (Bacillariophyta), a potentially harmful, marine diatom from Chilka Lake and other coastal localities of Odisha, India: Nomenclature, ... Department of Biological Science, Florida State University, Tallahassee, FL 32306–4370, USA; Department of Biology, Valdosta State University, Valdosta, GA ...

  6. Study on biological response to space radiation and its countermeasure

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong Il; Lee, Ju Woon; Kim, Dong Ho; Kim, Jae Hun; Song, Beom Suk; Kim, Jae Kyung; Park, Jong Heum; Kim, Jin Kyu [KAERI, Daejeon (Korea, Republic of)

    2011-12-15

    The purpose is to develop the core technologies for the advanced life supporting system based on radiation technology by 2015 and to be a member of G7 in the space technology research field. And it is the final aim that contribution for establishment of the self-supporting technology and national strength by 2020. To simulate the space environment of microgravity and expose to space radiation, denervation model was established in Gamma Phytotron. The changes in microflora population in animal model was shown. The effect of simulated microgravity and long-term exposure to irradiation was investigated. In the experiment of MARS 500, crews for expedition to Mars had been served by Korean space foods (Bulgogi, Bibimbap, Seaweed soup, Mulberry beverage, Kimchi, Sujeonggwa) for 120 days, then their immunity will be examined and compared with it on the ground.

  7. Study on biological response to space radiation and its countermeasure

    International Nuclear Information System (INIS)

    Choi, Jong Il; Lee, Ju Woon; Kim, Dong Ho; Kim, Jae Hun; Song, Beom Suk; Kim, Jae Kyung; Park, Jong Heum; Kim, Jin Kyu

    2011-12-01

    The purpose is to develop the core technologies for the advanced life supporting system based on radiation technology by 2015 and to be a member of G7 in the space technology research field. And it is the final aim that contribution for establishment of the self-supporting technology and national strength by 2020. To simulate the space environment of microgravity and expose to space radiation, denervation model was established in Gamma Phytotron. The changes in microflora population in animal model was shown. The effect of simulated microgravity and long-term exposure to irradiation was investigated. In the experiment of MARS 500, crews for expedition to Mars had been served by Korean space foods (Bulgogi, Bibimbap, Seaweed soup, Mulberry beverage, Kimchi, Sujeonggwa) for 120 days, then their immunity will be examined and compared with it on the ground

  8. Biological and medical effects of UV radiation on human health

    International Nuclear Information System (INIS)

    Piazena, H.

    1994-01-01

    Effecsts of UV radiation on human health are discussed. UV radiation is taken up through the skin and eyes. In the case of the eyes, the only known effects are damaging ones (e.g. cataracts). Irradiation of the skin, on the other hand, may either have a prophylactic and therapeutic effect or cause health problems if the exposure is too frequent and/or the dose too high. Positive effects are: Stimulation of the vitamin-D-3 synthesis and the autoimmune system, economisation of blood circulation, higher fitness, and the development of a UV protection system in the skin. Negative effects are: UV erythema, disturbances of the unspecific resistance and the immune system, and photocarcinogenesis. (orig.) [de

  9. Space radiation-induced bystander effect: kinetics of biologic responses, mechanisms, and significance of secondary radiations

    International Nuclear Information System (INIS)

    Gonon, Geraldine

    2011-01-01

    Widespread evidence indicates that exposure of cell cultures to a particles results in significant biological changes in both the irradiated and non-irradiated bystander cells in the population. The induction of non-targeted biological responses in cell cultures exposed to low fluences of high charge (Z) and high energy (E) particles is relevant to estimates of the health risks of space radiation and to radiotherapy. Here, we investigated the mechanisms underlying the induction of stressful effects in confluent normal human fibroblast cultures exposed to low fluences of 1000 MeV/u iron ions (linear energy transfer (LET) 151 keV/μm), 600 MeV/u silicon ions (LET 50 keV/μm) or 290 MeV/u carbon ions (LET 13 keV/μm). We compared the results with those obtained in cell cultures exposed, in parallel, to low fluences of 0.92 MeV/u a particles (LET 109 keV/μm). Induction of DNA damage, changes in gene expression, protein carbonylation and lipid peroxidation during 24 h after exposure of confluent cultures to mean doses as low as 0.2 cGy of iron or silicon ions strongly supported the propagation of stressful effects from irradiated to bystander cells. At a mean dose of 0.2 cGy, only 1 and 3 % of the cells would be targeted through the nucleus by an iron or silicon ion, respectively. Within 24 h post-irradiation, immunoblot analyses revealed significant increases in the levels of phospho-TP53 (serine 15), p21Waf1 (also known as CDKN1A), HDM2, phospho-ERK1/2, protein carbonylation and lipid peroxidation. The magnitude of the responses suggested participation of non-targeted cells in the response. Furthermore, when the irradiated cell populations were subcultured in fresh medium shortly after irradiation, greater than expected increases in the levels of these markers were also observed during 24 h. Together, the results imply a rapidly propagated and persistent bystander effect. In situ analyses in confluent cultures showed 53BP1 foci formation, a marker of DNA damage, in

  10. Working group 6: Health. 2. Biological radiation effects

    International Nuclear Information System (INIS)

    Maisin, J.R.

    1976-01-01

    Health hazards associated with the increasing development of nuclear energy have been evaluated for the Belgian population. Nuclear industry has been shown to be safer than conventional industry, epidemiological and toxicological data connected with the nuclear energy being more complete than those related to the conventional energy. Somatic and genetic effects of small and high doses of ionizing radiations on the Belgian population have been estimated. Small doses of ionizing radiations are expected to promote only carcinogenic effects. The latent period of cancers, the plateau region (period of high risk) and the absolute and relative risk expressed per rem per 10 6 people per year for leukaemia (having the highest risk) and for the ''other cancers'' have been also estimated. These estimations were obtained by linear extrapolation to the 1 rem level from observations made after irradiation at relatively high dose levels and much higher dose rates. Strict protective regulations have been recommended in order to reduce to a minimum the exposure of population to ionizing radiations as well as to get more information on the radioactive genetic and somatic consequences on population. (G.C.)

  11. Some progress on radiation chemistry of substances of biological interests and biological applications of radiation technology in China

    International Nuclear Information System (INIS)

    Wu Jilan; Fang Xingwang

    1995-01-01

    Studies in China on the detection method of irradiated food, mechanism of DNA damage induced by peroxidation, radiolysis of natural products and herbs are reviewed on the update open literature, and some progress on applications of radiation technology is summarized. (author)

  12. Ionizing radiation - one of the most important link of the energetic chain in biological cell

    Energy Technology Data Exchange (ETDEWEB)

    Goraczko, W. [Technical Univ. Poznan, Radio- and Photochemistry Dept., Poznan (Poland)

    1999-09-01

    High (large) and low (small) doses of ionizing radiation consistently induce opposite physiologic effects in biological systems. The effects of low doses cannot be inferred by interpolation between the result from groups exposed to high doses and controls irradiated only by Natural Background Radiation. Stimulation ('bio-positive') effects by low-level doses of ionizing radiation are called radiation hormesis. It is still controversial idea, however it was found that some biological objects (yeast, seeds, animals) after gamma irradiation by low-level doses (10-50 times more NBR) can increase their development. The result of present researches demonstrate that the excitation of living system by gamma quanta (high energy) initiates prolonged secondary emission that influences biota and activates many important processes in biological systems. According to the excitation theory of bio-molecules the author suggests that gamma irradiation in low-level doses excites such molecules as DNA and proteins, and this being followed by a long-termed secondary coherent radiation. The spectral analysis of this secondary emission confirmed the contribution of the UV component to the total emission. The data obtaining by using SPC method (single photon counting) make possible a partial understanding of the radiation hormesis phenomenon and suggest closer relationship to UV emission from biological systems during mitotic processes. The experiments with humic acid (high doses) and glycine (low doses) confirm the author hypothesis that gamma-irradiated organic compounds are capable to emit secondary radiation. This secondary radiation probably plays very significant role in the intercellular communication inside the living systems. In conclusion the author proposed de-excitation processes in bio-molecules as a common denominator of UV and ionizing radiation interacting with living cells. Finally he refers to the Cerenkov radiation which is created inside the biological cells

  13. Ionizing radiation - one of the most important link of the energetic chain in biological cell

    International Nuclear Information System (INIS)

    Goraczko, W.

    1999-01-01

    High (large) and low (small) doses of ionizing radiation consistently induce opposite physiologic effects in biological systems. The effects of low doses cannot be inferred by interpolation between the result from groups exposed to high doses and controls irradiated only by Natural Background Radiation. Stimulation ('bio-positive') effects by low-level doses of ionizing radiation are called radiation hormesis. It is still controversial idea, however it was found that some biological objects (yeast, seeds, animals) after gamma irradiation by low-level doses (10-50 times more NBR) can increase their development. The result of present researches demonstrate that the excitation of living system by gamma quanta (high energy) initiates prolonged secondary emission that influences biota and activates many important processes in biological systems. According to the excitation theory of bio-molecules the author suggests that gamma irradiation in low-level doses excites such molecules as DNA and proteins, and this being followed by a long-termed secondary coherent radiation. The spectral analysis of this secondary emission confirmed the contribution of the UV component to the total emission. The data obtaining by using SPC method (single photon counting) make possible a partial understanding of the radiation hormesis phenomenon and suggest closer relationship to UV emission from biological systems during mitotic processes. The experiments with humic acid (high doses) and glycine (low doses) confirm the author hypothesis that gamma-irradiated organic compounds are capable to emit secondary radiation. This secondary radiation probably plays very significant role in the intercellular communication inside the living systems. In conclusion the author proposed de-excitation processes in bio-molecules as a common denominator of UV and ionizing radiation interacting with living cells. Finally he refers to the Cerenkov radiation which is created inside the biological cells. Because

  14. The effects on populations of exposure to low levels of ionizing radiation. Report of the Advisory Committee on the Biological Effects of Ionizing Radiations

    International Nuclear Information System (INIS)

    1972-11-01

    In the summer of 1970, the Federal Radiation Council (whose activities have since been transferred to the Radiation Office of the EPA) asked the National Academy of Sciences for information relevant to an evaluation of present radiation protection guides. This report is in response to that request. It presents a summary and analysis, by members of the Advisory Committee on the Biological Effects of Ionizing Radiations and its subcommittees, of current knowledge relating to risks from exposure to ionizing radiation. In many respects, the report is a sequel to the reports of the Committee on the Biological Effects of Atomic Radiation, published by the NAS-NRC from 1956 to 1961

  15. Biological effect of non-ionizing radiations on microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Kikuo; Yamamoto, Takayoshi [Osaka Univ., Radioisotope Research Center, Suita, Osaka (Japan); Nakaoka, Yasuo [Osaka Univ., Graduate School of Engineering Science, Department of Biophysical Engineering, Toyonaka, Osaka (Japan)

    2000-05-01

    We studied the effect of extremely low frequency magnetic fields (ELF-MF) of 60-Hz and 500 mT on the growth and the mutation frequency of the budding yeast S.cerevisiae and on the behavior of the ciliate Paramecium multimicronucleatum. The growth rate and mutation frequencies of several strains of S.cerevisiae (wild type and radiation sensitive mutants, rad or rev) were examined but no significant difference was observed. Moreover, the behavior of P.multimicronucleatum under the ELF-MF was examined. When exposed to a vertical field of 0.6 T, the cells accumulated at the upper end of the cuvette. (author)

  16. Biological effect of non-ionizing radiations on microorganisms

    International Nuclear Information System (INIS)

    Shimizu, Kikuo; Yamamoto, Takayoshi; Nakaoka, Yasuo

    2000-01-01

    We studied the effect of extremely low frequency magnetic fields (ELF-MF) of 60-Hz and 500 mT on the growth and the mutation frequency of the budding yeast S.cerevisiae and on the behavior of the ciliate Paramecium multimicronucleatum. The growth rate and mutation frequencies of several strains of S.cerevisiae (wild type and radiation sensitive mutants, rad or rev) were examined but no significant difference was observed. Moreover, the behavior of P.multimicronucleatum under the ELF-MF was examined. When exposed to a vertical field of 0.6 T, the cells accumulated at the upper end of the cuvette. (author)

  17. Advances in dosimetry and biological predictors of radiation-induced esophagitis

    Directory of Open Access Journals (Sweden)

    Yu Y

    2016-01-01

    Full Text Available Yang Yu,1 Hui Guan,1 Yuanli Dong,1 Ligang Xing,2 Xiaolin Li2 1School of Medicine and Life Sciences, Shandong Academy of Medical Sciences, University of Jinan, Jinan, 2Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong Province, People’s Republic of China Objective: To summarize the research progress about the dosimetry and biological predictors of radiation-induced esophagitis.Methods: We performed a systematic literature review addressing radiation esophagitis in the treatment of lung cancer published between January 2009 and May 2015 in the PubMed full-text database index systems.Results: Twenty-eight eligible documents were included in the final analysis. Many clinical factors were related to the risk of radiation esophagitis, such as elder patients, concurrent chemoradiotherapy, and the intense radiotherapy regimen (hyperfractionated radiotherapy or stereotactic body radiotherapy. The parameters including Dmax, Dmean, V20, V30, V50, and V55 may be valuable in predicting the occurrence of radiation esophagitis in patients receiving concurrent chemoradiotherapy. Genetic variants in inflammation-related genes are also associated with radiation-induced toxicity.Conclusion: Dosimetry and biological factors of radiation-induced esophagitis provide clinical information to decrease its occurrence and grade during radiotherapy. More prospective studies are warranted to confirm their prediction efficacy. Keywords: lung cancer, esophagitis, radiation injuries, predictors

  18. Basic molecular biology in radiation-induced carcinogenesis

    International Nuclear Information System (INIS)

    Rytoemaa, T.

    1992-01-01

    The tumour suppressor gene p53 is 'guardian of the genome'. If a DNA molecule (each chromosome has one DNA molecule) is damaged by an external factor, such as ionizing radiation, the protein product of the p53 gene stops the cell's proliferative activity until the damage is repaired. If the repair fails, the p53 gene product normally triggers programmed death of the cell. P53 gene itself is commonly damaged by radiation (or by another DNA-damaging factor). The altered gene product fails to control the integrity of the genome, and it also prevents the guardian action of the protein which is produced by the intact allele (each cell has two p53 genes). Under these circumstances any subsequent damage to DNA, induced e.g. by a chemical, is easily 'fixed'. Potentially critical sites for an additional DNA damage are the proto-oncogens (when damaged these genes are called oncogens), which commonly act as components of the regulatory network in a cell. Permanent malfunction of the signal network may then lead to uncontrolled cell growth, resulting in a malignant clone (=cancer). This simplified molecular model seems to be the common mechanism in many (or most) human cancers. (orig.)

  19. Biological Effects of Laser Radiation. Volume II. Review of Our Studies on Biological Effects of Laser Radiation-1965-1971.

    Science.gov (United States)

    1978-10-17

    improve dental therapy and provide improved methods for prevention of dental caries and for prophylaxis. -39- DENTISTRY 1. Lobene, R and Fine, S...alter the immunological capability/virulence ratio of influenza virus; gross and microscopic descriptions of lesions, their natural history, and...Clinical Studies 22 Chapter 7 Ultraviolet Studies - Eyes and Skin 24 Chapter 8 Dental Studies 35 Chapter 9 Mechanisms of Interaction of Laser Radiation

  20. Combining Radiation Epidemiology With Molecular Biology-Changing From Health Risk Estimates to Therapeutic Intervention.

    Science.gov (United States)

    Abend, Michael; Port, Matthias

    2016-08-01

    The authors herein summarize six presentations dedicated to the key session "molecular radiation epidemiology" of the ConRad meeting 2015. These presentations were chosen in order to highlight the promise when combining conventional radiation epidemiology with molecular biology. Conventional radiation epidemiology uses dose estimates for risk predictions on health. However, combined with molecular biology, dose-dependent bioindicators of effect hold the promise to improve clinical diagnostics and to provide target molecules for potential therapeutic intervention. One out of the six presentations exemplified the use of radiation-induced molecular changes as biomarkers of exposure by measuring stabile chromosomal translocations. The remaining five presentations focused on molecular changes used as bioindicators of the effect. These bioindicators of the effect could be used for diagnostic purposes on colon cancers (genomic instability), thyroid cancer (CLIP2), or head and neck squamous cell cancers. Therapeutic implications of gene expression changes were examined in Chernobyl thyroid cancer victims and Mayak workers.

  1. Facilities for external radiation accessible for investigation on biological studies - progress report may 2004

    International Nuclear Information System (INIS)

    Gaillard-Lecanu, E.; Authier, N.; Verrey, B.; Bailly, I.; Bordy, J.M.; Coffigny, H.; Cortela, L.; Duval, D.; Leplat, J.J.; Poncy, J.L.; Testard, I.; Thuret, J.Y.

    2004-01-01

    The Life Science Division of the Atomic Energy Commission is making an inventory of the various radiation sources accessible for investigation on the biological effects of ionizing radiation. In this field, a wide range of studies is being carried out at the Life Science Division, attempting to characterize the kind of lesions with their early biological consequences (on the various cell compartments) and their late biological consequences (deterministic or stochastic effects), in relation to the radiation type and dose, especially at low doses. Several experimental models are available: plants, bacteria, eukaryotic cells from yeast up to mammalian cells and in vivo studies, mostly on rodents, in order to characterize the somatic late effects and the hereditary effects. Due to the significant cost of these facilities, also to their specific properties (nature of the radiation, dose and dose rate, possible accuracy of the irradiation at the molecular level), the closeness is no longer the only criteria for biologists to make a choice. The current evolution is to set up irradiation infrastructures combining ionizing radiation sources themselves and specific tools dedicated to biological studies: cell or molecular biology laboratories, animal facilities. The purpose, in this new frame, is to provide biologists with the most suitable facilities, and, if possible, to change these facilities according to requirements in radiobiology. In this report, the basics of interactions of ionizing radiation with biological tissues are briefly introduced, followed by a presentation of some of the facilities available at the CEA for radiobiological studies. This panorama is not a comprehensive one, new data will be included as they advance, whether reporting existing facilities or if a new one is developed. (authors)

  2. Biological effect of low-dose application beta-radiation on the gingival mucosa of dogs

    International Nuclear Information System (INIS)

    Ippolitov, Yu.A.; Kovtun, N.N.; Timofeev, L.V.

    1999-01-01

    Biological effect of low-dose application beta-radiation on the gingival mucosa of dogs is studied. Obtained data illustrate the interactions between tissues in local exposure of live tissue to beta-radiation and determine the threshold total dose as 400 sGy. Higher doses lead to secondary changes in the gingival mucosa after which the tissue barrier does not recover [ru

  3. The risk of small radiation doses from the point of view of molecular biology

    International Nuclear Information System (INIS)

    Pfeiffer, H.; Stoll, E.

    2001-01-01

    A recent publication in 'Nature' reported that the selective inactivation of a single specific gene in mice increases life expectancy as well as resistance against noxious H 2 O 2 or UV irradiation. These results can be explained by different mechanisms and it should be possible to get further experimental evidence for or against these explanations. With respect to radiation protection these results indicate, that molecular biology will help to clarify controversial topics related to radiation risk. (orig.) [de

  4. Biological impact of high-dose and dose-rate radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Maliev, V.; Popov, D. [Russian Academy of Science, Vladicaucas (Russian Federation); Jones, J.; Gonda, S. [NASA -Johnson Space Center, Houston (United States); Prasad, K.; Viliam, C.; Haase, G. [Antioxida nt Research Institute, Premier Micronutrient Corporation, Novato (United States); Kirchin, V. [Moscow State Veterinary and Biotechnology Acade my, Moscow (Russian Federation); Rachael, C. [University Space Research Association, Colorado (United States)

    2006-07-01

    Experimental anti-radiation vaccine is a power tool of immune - prophylaxis of the acute radiation disease. Existing principles of treatment of the acute radiation dis ease are based on a correction of developing patho-physiological and biochemical processes within the first days after irradiation. Protection from radiation is built on the general principles of immunology and has two main forms - active and passive immunization. Active immunization by the essential radiation toxins of specific radiation determinant (S.D.R.) group allows significantly reduce the lethality and increase duration of life among animals that are irradiated by lethal and sub-lethal doses of gamma radiation.The radiation toxins of S.D.R. group have antigenic properties that are specific for different forms of acute radiation disease. Development of the specific and active immune reaction after intramuscular injection of radiation toxins allows optimize a manifestation of a clinical picture and stabilize laboratory parameters of the acute radiation syndromes. Passive immunization by the anti-radiation serum or preparations of immune-globulins gives a manifestation of the radioprotection effects immediately after this kind of preparation are injected into organisms of mammals. Providing passive immunization by preparations of anti-radiations immune-globulins is possible in different periods of time after radiation. Providing active immunization by preparations of S.D.R. group is possible only to achieve a prophylaxis goal and form the protection effects that start to work in 18 - 35 days after an injection of biological active S.D.R. substance has been administrated. However active and passive immunizations by essential anti-radiation toxins and preparations of gamma-globulins extracted from a hyper-immune serum of a horse have significantly different medical prescriptions for application and depend on many factors like a type of radiation, a power of radiation, absorption doses, a time of

  5. Biological impact of high-dose and dose-rate radiation exposure

    International Nuclear Information System (INIS)

    Maliev, V.; Popov, D.; Jones, J.; Gonda, S.; Prasad, K.; Viliam, C.; Haase, G.; Kirchin, V.; Rachael, C.

    2006-01-01

    Experimental anti-radiation vaccine is a power tool of immune - prophylaxis of the acute radiation disease. Existing principles of treatment of the acute radiation dis ease are based on a correction of developing patho-physiological and biochemical processes within the first days after irradiation. Protection from radiation is built on the general principles of immunology and has two main forms - active and passive immunization. Active immunization by the essential radiation toxins of specific radiation determinant (S.D.R.) group allows significantly reduce the lethality and increase duration of life among animals that are irradiated by lethal and sub-lethal doses of gamma radiation.The radiation toxins of S.D.R. group have antigenic properties that are specific for different forms of acute radiation disease. Development of the specific and active immune reaction after intramuscular injection of radiation toxins allows optimize a manifestation of a clinical picture and stabilize laboratory parameters of the acute radiation syndromes. Passive immunization by the anti-radiation serum or preparations of immune-globulins gives a manifestation of the radioprotection effects immediately after this kind of preparation are injected into organisms of mammals. Providing passive immunization by preparations of anti-radiations immune-globulins is possible in different periods of time after radiation. Providing active immunization by preparations of S.D.R. group is possible only to achieve a prophylaxis goal and form the protection effects that start to work in 18 - 35 days after an injection of biological active S.D.R. substance has been administrated. However active and passive immunizations by essential anti-radiation toxins and preparations of gamma-globulins extracted from a hyper-immune serum of a horse have significantly different medical prescriptions for application and depend on many factors like a type of radiation, a power of radiation, absorption doses, a time of

  6. Information on biological health effects of ionizing radiation and radionuclides: the rule of a web site

    International Nuclear Information System (INIS)

    Comte, A.; Gaillard-Lecanu, E.; Flury-Herard, A.; Ourly, F.; Hemidy, P.; Lallemand, J.

    2006-01-01

    The purpose of this project is to provide a source of information on biological and health effects of radionuclides and ionizing radiation in an easy to use format. Reported work is made up of two distinct parts: data sheets for selected radionuclides and a web file. Data sheets: Specific radiation data sheets provide an overview of the properties, the environmental behaviour, the different pathways of human exposure and the biological and health consequences of selected radionuclides. Radionuclides that have been selected are those commonly dealt with in nuclear industry (and in other areas such as medicine) and released to the environment or naturally occurring (plutonium, tritium, carbon 14). Data sheets corresponding to the different radionuclides are based on the main sources of scientific information in dosimetry, epidemiology, radiobiology and radiation protection. These data sheets are intended for radiation protection specialists and physicians. They include: main physical and chemical characteristics, main radiation protection data: dose coefficients (public, workers), dose limits sources, total released estimate (nuclear industry, atmospheric tests, main pathway of human exposure and biological behaviour, biological and health effects, medical supervision, treatment a list of the main references, appendix providing accurate information. Web file: http://www-dsv.cea.fr/doc/carmin_ext/fond.php This web file provides a source of information on biological and health effects of ionizing radiation and biological basic knowledge of radiation protection. Available for consultation via Internet, compiled information provides, in a same file, subjects as varied as biological mechanisms, ionizing radiations action, biological and health effects, risk assessment This file is mainly intended to assist in informing and training of non-specialist readership (students, teaching on radiation protection basic knowledge. This electronic document is divided in three

  7. Book review: The relative biological effectiveness of radiations of different quality

    International Nuclear Information System (INIS)

    Kerr, G.D.

    1991-01-01

    The Relative Biological Effectiveness of Radiations of Different Quality is a survey of the literature relevant to the selection of relative biological effectiveness values for use in arriving at values of Q for neutrons and other particles with a high rate of linear energy transfer. Except for internal emitters, there is no data on which RBE for high-LET radiations can be estimated for humans. The focus of this report is on RBE data from plant and animal studies to the almost total exclusion of RBE data from human studies

  8. Considerations on hypoxic conditions. On the past setback of classic radiation biology

    International Nuclear Information System (INIS)

    Nakatsugawa, Shigekazu; Klimova, S.V.; Tamasu, Shogo; Nakamura, Hideaki; Murayama, Chieko

    2002-01-01

    Considerations on hypoxic cancer cell environment are made on classic radiation biology concept and on a new proposal of the anti-cancer strategy. Classic radiation biology knowledge of hypoxic cancer cells has produced many of clinical trials, which, however, have failed after all. This is because the knowledge is that the cells are recognized to be in a rather static hypoxic condition. Based on authors' investigations, made is the proposal that improvement of dynamic, acute hypoxic conditions yielded via blood circulation between the heterogeneous malignant cancer cells and the dynamic homeostatic systems of normal cells including immunity is important as one of cancer therapy approaches. (N.I.)

  9. Medical-biological aspects of radiation effects in Daphnia magna

    International Nuclear Information System (INIS)

    Sarapultseva, E; Ustenko, K; Uskalova, D; Savina, N

    2017-01-01

    We have shown that γ-irradiation at doses of 100 and 1000 mGy significantly compromised fecundity and reproductive success of the directly exposed D. magna . These effects were also observed among the non-exposed first-generation progeny of irradiated parents, thus implying the manifestation of transgenerational effects in Daphnia . We have also shown that compromised viability of irradiated D. magna can be attributed cytotoxic effects of irradiation. It would therefore appear that the compromised viability may be attributed to the cytotoxic effects resulted from epigenetic changes affecting some metabolic pathways involved in detoxification of free-radicals. Additionally we have analyzed more distant progeny of irradiated at doses of 10, 100 and 1000 mGy Daphnia . Our data demonstrated that multicellular crustacean D. magna represent a very useful experimental model for analyse of long-term effects of ionising radiation at the organismal level. (paper)

  10. Ablation of biological tissues by radiation of strontium vapor laser

    Energy Technology Data Exchange (ETDEWEB)

    Soldatov, A. N., E-mail: general@tic.tsu.ru; Vasilieva, A. V., E-mail: anita-tomsk@mail.ru [National Research Tomsk State University, Lenin ave., 36, 634050, Tomsk (Russian Federation)

    2015-11-17

    A two-stage laser system consisting of a master oscillator and a power amplifier based on sources of self- contained transitions in pairs SrI and SrII has been developed. The radiation spectrum contains 8 laser lines generating in the range of 1 – 6.45 μm, with a generation pulse length of 50 – 150 ns, and pulse energy of ∼ 2.5 mJ. The divergence of the output beam was close to the diffraction and did not exceed 0.5 mrad. The control range of the laser pulse repetition rate varied from 10 to 15 000 Hz. The given laser system has allowed to perform ablation of bone tissue samples without visible thermal damage.

  11. Medical-biological aspects of radiation effects in Daphnia magna

    Science.gov (United States)

    Sarapultseva, E.; Uskalova, D.; Savina, N.; Ustenko, K.

    2017-01-01

    We have shown that γ-irradiation at doses of 100 and 1000 mGy significantly compromised fecundity and reproductive success of the directly exposed D. magna. These effects were also observed among the non-exposed first-generation progeny of irradiated parents, thus implying the manifestation of transgenerational effects in Daphnia. We have also shown that compromised viability of irradiated D. magna can be attributed cytotoxic effects of irradiation. It would therefore appear that the compromised viability may be attributed to the cytotoxic effects resulted from epigenetic changes affecting some metabolic pathways involved in detoxification of free-radicals. Additionally we have analyzed more distant progeny of irradiated at doses of 10, 100 and 1000 mGy Daphnia. Our data demonstrated that multicellular crustacean D. magna represent a very useful experimental model for analyse of long-term effects of ionising radiation at the organismal level.

  12. Radiation degradation of biological waste (aflatoxins) produced in food laboratory

    International Nuclear Information System (INIS)

    Rogovschi, Vladimir Dias

    2009-01-01

    Many filamentous fungi can produce secondary metabolites, called mycotoxins, which can be found in food and agricultural products. One of the main genera of myco toxigenic fungi related to the food chain is the Aspergillus spp. There are over 400 mycotoxins described in the literature, the most common the aflatoxins B1, B2, G1 and G2. The mycotoxins are commonly found in foods and are considered one of the most dangerous contaminants. The aflatoxin B1 is classified in group one by the International Agency of Research on Cancer. Aflatoxins resisting for more than one hour in autoclave making it necessary to other means of degradation of these toxins. This work aimed to observe the effects of gamma radiation of 60 Co and electron beams in the degradation of aflatoxins and compare the damage caused on the morphology of the Aspergillus flavus. The fungus was grown on potato dextrose agar (PDA) for 10 days and was subsequently transferred to coconut agar medium, and maintained for 14 days at 25 degree C. After this step the coconut agar was ground to become a homogeneous pasty and was irradiated with doses of 2.5, 5.0, 10 and 20 kGy. The samples used in scanning electron microscopy were irradiated with doses of 0, 2.5, 5.0, 10 and 20 kGy with sources of 60 Co and electron beams. Irradiation with electron accelerator showed a slightly higher degradation to gamma radiation, reducing 29.93 %, 34.50 %, 52.63 % and 72.30 % for doses of 2.5, 5.0, 10 and 20 kGy, respectively. The Scanning Electron Microscopy showed that doses of 2.5 to 10 kGy did not cause damage to the fungus, but with a dose of 20 kGy it can be observed fungal damage to structures. (author)

  13. Clinical, biological, histological features and treatment of oral mucositis induced by radiation therapy: a literature review

    International Nuclear Information System (INIS)

    Bonan, Paulo Rogerio Ferreti; Lopes, Marcio Ajudarte; Almeida, Oslei Paes de; Alves, Fabio de Abreu

    2005-01-01

    The oral mucositis is a main side effect of radiotherapy on head and neck, initiating two weeks after the beginning of the treatment. It is characterized by sensation of local burning to intense pain, leading in several cases, to the interruption of the treatment. The purpose of this work is to review the main published studies that discuss the clinical, biological and histopathological features of oral mucositis induced by radiation therapy and to describe the main approaches recommended to prevent or to treat it. Although the clinical features of mucositis are intensively described in the literature, few studies address the histopathological alterations in oral mucositis and only recently, its biological processes have been investigated. The biological mechanisms involved in the radiation tissue damage have been only recently discussed and there is no consensus among treatment modalities. Yet, the progressive knowledge in the histopathology and biological characteristics of oral mucositis probably will lead to more effective in prevention and control strategies. (author)

  14. Gamma-irradiated onions as a biological indicator of radiation dose

    International Nuclear Information System (INIS)

    Vaijapurkar, S.G.; Agarwal, Deepshikha; Chaudhuri, S.K.; Ram Senwar, Kana; Bhatnagar, P.K.

    2001-01-01

    Post-irradiation identification and dose estimation are required to assess the radiation-induced effects on living things in any nuclear emergency. In this study, radiation-induced morphological/cytological changes i.e., number of root formation and its length, shooting length, reduction in mitotic index, micronuclei formation and chromosomal aberrations in the root tip cells of gamma-irradiated onions at lower doses (50-2000 cGy) are reported. The capabilities of this biological species to store the radiation-induced information are also studied

  15. Pioneer 10 jovian encounter: radiation dose and implications for biological lethality.

    Science.gov (United States)

    Miller, M W; Kaufman, G E; Maillie, H D

    1975-02-28

    In its recent Jupiter flyby Pioneer 10 passed through a belt of intense particulate radiation. The radiation dose on the outer surface of the spacecraft was at least 4.9 x 10(5) rads from electrons plus 2.9 x 10(6) rads from protons, sufficient to cause significant microbial decontamination. The radiation dose inside Pioneer 10, approximately 2.8 x 10(5) rads, was less likely to cause microbial decontamination but would be lethal to man and to most multicellular biological organisms.

  16. Laboratory of Radiation Biology progress report, August 15, 1975--August 14, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Powers, E.L.

    1976-05-01

    Studies on action of inorganic radiation sensitizers included the following: roles of e/sup -/aq.OH and H/sub 2/O/sub 2/; metal ions and biological radiation sensitivity; iron as a sensitizer; and cellular uptake of solutes. Studies on organic sensitizers and protectors included the following: anoxic protection; anoxic desensitization when PNAP is present; effects of additives in air; and oxygen-dependent sensitization. Studies were also conducted on radioinduced mutations in spores of Bacillus megaterium and effects of radiation on inactivation of DNA in Bacillus Subtilis. (HLW)

  17. Laboratory of Radiation Biology progress report, August 15, 1975--August 14, 1976

    International Nuclear Information System (INIS)

    Powers, E.L.

    1976-05-01

    Studies on action of inorganic radiation sensitizers included the following: roles of e - aq.OH and H 2 O 2 ; metal ions and biological radiation sensitivity; iron as a sensitizer; and cellular uptake of solutes. Studies on organic sensitizers and protectors included the following: anoxic protection; anoxic desensitization when PNAP is present; effects of additives in air; and oxygen-dependent sensitization. Studies were also conducted on radioinduced mutations in spores of Bacillus megaterium and effects of radiation on inactivation of DNA in Bacillus Subtilis

  18. Radiation degradation of alginate and some results of biological effect of degraded alginate on plants

    Energy Technology Data Exchange (ETDEWEB)

    Hien, N.Q.; Hai, L.; Luan, L.Q.; Hanh, T.T. [Nuclear Research Institute, Dalat (Viet Nam); Nagasawa, Naotsugu; Yoshii, Fumio; Makuuchi, Keizo; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2000-03-01

    Radiation degradation yields (Gd) of alginate in aqueous solution with different concentration were determined by viscometry method. The relationship between Gd and the alginate concentration was found out as: Gd=33.5 x C{sup -0.68}, with C% (w/v) and dry alginate referred to C=100%. An empirical equation for preparing degraded alginate with the desired low viscometry average molecular weight (Mv) by radiation was proposed. Alginate extracted directly horn seaweed'Sagassum, degraded by radiation was used for field experiments and results of the biological effect on plants (tea, carrot, chrysanthemum) were presented. (author)

  19. Application of biological dosimetry in accidental radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Nosal, M.; Batora, I.; Kolesar, D.; Stojkovic, J. (Komenskeho Univ., Bratislava (Czechoslovakia). Lekarska Fakulta); Gaal, P.; Sklovsky, A. (Krajska Hygienicka Stanica, Bratislava (Czechoslovakia)); Cizova, O. (Sexuologicka Ambulancia KUNZ, Bratislava (Czechoslovakia))

    1982-03-01

    The case is described of accidental irradiation of a male person with /sup 137/Cs of an activity of 24.71 GBq. The first estimate induced a reasonable suspicion that the absorbed dose could be very high and life-threatening. On the other hand the clinical picture, usual laboratory examinations, findings in the fluorescent blood count, the analysis of chromosomal count of lymphocytes in the peripheral blood, the spermiogram, and the negative post-irradiation porphyrinuria suggested that the absorbed dose could be much lower than the original estimate. The results of dosimetry obtained after the reconstruction of the accident by measuring on a phantom revealed that the actual dose was very close to that presumed from the results of biological dosimetry during the first days of examination of the patient.

  20. Application of biological dosimetry in accident radiation exposure

    International Nuclear Information System (INIS)

    Nosal, M.; Batora, I.; Kolesar, D.; Stojkovic, J.; Cizova, O.

    1982-01-01

    The case is described of accidental irradiation of a male person with 137 Cs of an activity of 24.71 GBq. The first estimate induced a reasonable suspicion that the absorbed dose could be very high and life-threatening. On the other hand the clinical picture, usual laboratory examinations, findings in the fluorescent blood count, the analysis of chromosomal count of lymphocytes in the peripheral blood, the spermiogram, and the negative post-irradiation porphyrinuria suggested that the absorbed dose could be much lower than the original estimate. The results of dosimetry obtained after the reconstruction of the accident by measuring on a phantom revealed that the actual dose was very close to that presumed from the results of biological dosimetry during the first days of examination of the patient. (author)

  1. Radiation degradation of polysaccharides and induced biological activity

    Energy Technology Data Exchange (ETDEWEB)

    Nagasawa, Naotsugu; Yoshii, Fumio; Makuuchi Keizo; Kume Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Mitomo, Hiroshi [Gunma Univ., Kiryu (Japan). Faculty of Engineering

    1999-09-01

    Relationship between irradiation effect of polysaccharides and induced biological activity for plants has been investigated. Sodium alginate was irradiated by gamma-rays from a Co-60 source in liquid state (aqueous solution) and in solid state (powder form). Measurement of molecular weight and analysis of UV spectra of irradiated sodium alginate have been carried out. The molecular weight was decreased by irradiation in both conditions. New absorbance peak derived from double bond or/and carbonyl group was appeared at close to 267 nm by irradiation in UV spectra. It was found that alginate having molecular weight about 10,000 is most suitable to used as growth promoter in plants. To obtain the molecular weight of 10,000 by irradiation, the necessary doses are 100 kGy in liquid state and 500 kGy in solid state, respectively. (author)

  2. Genetic determination of the biological radiation response in inbred mice lines

    International Nuclear Information System (INIS)

    Gomolka, M.; Hornhardt, S.; Jung, T.

    2000-01-01

    Variation in radiation sensitivity and radiation resistance is influenced by the genetic constitution of an individual. Loss of function of genes involved in DNA repair, cell cycle or controlled cell death can have serious consequences on individual radiation sensitivity. For example, individuals suffering on the clinical syndrome of Ataxia telangiectasia exhibit radiation sensitivity in the order of 2-3 magnitudes higher than other cancer patients. For radiation protection it is important to clarify the role of genetic predisposition for radiation sensitivity in clinical healthy people. Therefore, data were collected from the literature describing the genetic variation (heritability) of radiation sensitivity in the mouse model. A heritability of 30-50% was calculated for 27 inbred mice lines by Roderick (1963) based on days of survival after a daily dose of 1 Gy γ-irradiation. The following inbred lines were described in the literature as radiation sensitive (phenotypical markers were e.g., time of survival, mortality, reduction in fertility post exposure): SWR, RIII, NC, K, HLG, DBA, CBA, BALB/c, A, AKR. Radiation resistance was demonstrated in SJL, SEC, RF, MA, C58, C57BR, BDP and 129. Parameter of longevity, some physiological, biochemical and immunological parameters as given in the data bank of the Jackson Laboratory, U.S.A., were compared between radiation sensitive and radiation resistant inbred strains. No correlation was seen for the most of the parameters except for the development of breast cancer. In 6 out of 10 radiosensitive inbred strains breast cancer is described while only 1 of 8 strains exhibits breast cancer. The higher heritability of 30-50% in spite of a very complex phenotype like survival and the correlation between radiosensitivity and tumour incidence show that individual genetic susceptibility is important on the biological radiation reaction. (orig.) [de

  3. Uses of chemotherapy together with radiation, and its biological basis

    International Nuclear Information System (INIS)

    Watanabe, Ikuo; Terashima, Toyozo

    1978-01-01

    Effect of use of anticancer drugs together with radiation, especially effects of Actinomycin D (AMD), Bleomycin (BLM), and Adriamycin (Ad) which seemed to have synergistic effect, and other substances which have possibility to have synergistic effect were described. It was clarified that AMD out of them showed synergistic effect to inhibit repair of sublethel damage induced by irradiation in addition to anticancer effect itself. Therefore, it is thought that use of AMD is effective especially to cancer with high radioresistance and it is better to administer this drug just before or just after irradiation. It seems to be better to administer at one time with high concentration in the allowable range. It is difficult to come to a conclusion as to BLM and Ad, generalized as well as the conclusion of AMD, but it seems to be better to use BLM and Ad together with irradiation at the same time. As BLM is highly effective especially to epithelial cells, it must be necessary to investigate whether there is a difference of characteristics between cells. In any case, there are two great factors, the concentration and action time (containing the time remaining in vivo) of drugs, and moreover, another factor, time relation to irradiation is added. Therefore, an experiment schedule is complicated so much, and it is important to study quantitatively on the basis of systematic experimental plan. As to clinical application of them, it is necessary to perform an experiment in vitro which is exullent in estimation and an experiment in vivo which certified the effects in keeping organic cooperation. (Tsunoda, M.)

  4. Biological effects of radiation in combination with other physical, chemical or biological agents. Annex L

    International Nuclear Information System (INIS)

    1982-01-01

    This Annex considers the combined action of radiation with potentially important environmental conditions. Since there is a scarcity of systematic data on which an analysis of combined effects can be based, this Annex will be more hypothetical and will attempt to suggest definitions, to identify suitable methods of analysis, to select from a large amount of diffuse information the conditions and the data of importance for further consideration and to provide suggestions for future research. For humans in environmental circumstances the UNSCEAR Committee has been unable to document any clear case of synergistic interaction between radiation and other agents, which could lead to substantial modifications of the risk estimates for significant sections of the population.

  5. Non-Directional Radiation Spread Modeling and Non-Invasive Estimating the Radiation Scattering and Absorption Parameters in Biological Tissue

    Directory of Open Access Journals (Sweden)

    S. Yu. Makarov

    2015-01-01

    Full Text Available The article dwells on a development of new non-invasive measurement methods of optical parameters of biological tissues, which are responsible for the scattering and absorption of monochromatic radiation. It is known from the theory of radiation transfer [1] that for strongly scattering media, to which many biological tissues pertain, such parameters are parameters of diffusion approximation, as well as a scattering coefficient and an anisotropy parameter.Based on statistical modeling the paper examines a spread of non-directional radiation from a Lambert light beam with the natural polarization that illuminates a surface of the biological tissue. Statistical modeling is based on the Monte Carlo method [2]. Thus, to have the correct energy coefficient values of Fresnel reflection and transmission in simulation of such radiation by Monte Carlo method the author uses his finding that is a function of the statistical representation for the incidence of model photons [3]. The paper describes in detail a principle of fixing the power transmitted by the non-directional radiation into biological tissue [3], and the equations of a power balance in this case.Further, the paper describes the diffusion approximation of a radiation transfer theory, often used in simulation of radiation propagation in strongly scattering media and shows its application in case of fixing the power transmitted into the tissue. Thus, to represent an uneven power distribution is used an approximating expression in conditions of fixing a total input power. The paper reveals behavior peculiarities of solution on the surface of the biological tissue inside and outside of the incident beam. It is shown that the solution in the region outside of the incident beam (especially far away from it, essentially, depends neither on the particular power distribution across the surface, being a part of the tissue, nor on the refractive index of the biological tissue. It is determined only by

  6. Attenuation of biologically effective UV radiation in tropical Atlantic waters measured with a biochemical DNA dosimeter

    NARCIS (Netherlands)

    Boelen, P.; Obernosterer, I; Vink, A.A; Buma, A.G.J.

    A biochemical dosimeter was developed to study the attenuation of biologically effective UV radiation in marine tropical waters. Small quartz vials were used containing a solution of DNA molecules; the vials were incubated at discrete water depths. Subsequently, DNA damage was determined in these

  7. Attenuation of biologically effective UV radiation in tropical atlantic waters measured with a biochemical DNA dosimeter

    NARCIS (Netherlands)

    Boelen, P.; Obernosterer, I.; Vink, A.A.; Buma, A.G.J.

    1999-01-01

    A biochemical dosimeter was developed to study the attenuation of biologically effective UV radiation in marine tropical waters. Small quartz vials were used containing a solution of DNA molecules; the vials were incubated at discrete water depths. Subsequently, DNA damage was determined in these

  8. Physical, chemical, and biological properties of radiocerium relevant to radiation protection guidelines

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Present knowledge of the relevant physical, chemical, and biological properties of radiocerium as a basis for establishing radiation protection guidelines is summarized. The first section of the report reviews the chemical and physical properties of radiocerium relative to the biological behavior of internally-deposited cerium and other lanthanides. The second section of the report gives the sources of radiocerium in the environment and the pathways to man. The third section of the report describes the metabolic fate of cerium in several mammalian species as a basis for predicting its metabolic fate in man. The fourth section of the report considers the biomedical effects of radiocerium in light of extensive animal experimentation. The last two sections of the report describe the history of radiation protection guidelines for radiocerium and summarize data required for evaluating the adequacy of current radiation protection guidelines. Each section begins with a summary of the most important findings that follow

  9. WE-DE-202-00: Connecting Radiation Physics with Computational Biology

    International Nuclear Information System (INIS)

    2016-01-01

    Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are the most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological

  10. WE-DE-202-00: Connecting Radiation Physics with Computational Biology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are the most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological

  11. 'K' contribution to the biological effect of ionizing radiations

    International Nuclear Information System (INIS)

    Boissiere, Arnaud

    2004-01-01

    The aim of this work is to determine the importance of 'K' ionizations on DNA as critical physical events initiating the biological effects of ionizing radiation, in particular in human cells. Ultra-soft X-rays are used as a probe of core ionization events. A decisive test consists in comparing the biological effects at 250 eV and 350 eV (before and after the carbon K - threshold). The results show a sharp increase of the biological efficiency for both cellular inactivation and chromosomal exchange aberration above the carbon K-threshold, correlated with the one of core events occurring in DNA atoms. The heavy ion irradiation displays again the paradoxical behaviour of cellular inactivation cross sections as a function of LET. Finally, the 'K' event contribution to cellular inactivation of usual low LET radiation is estimated to be about 75%. (author) [fr

  12. Biological Effects of Laser Radiation. Volume IV. Optical Second Harmonic Generation in Biological Tissues.

    Science.gov (United States)

    1978-10-17

    harmonic generation in ocular tissue may be of significance to vision (Fine and Hansen, 1971). Although second-harmonic radiation was observed from...efficiency of CC1 4 . The parameter values used in this computacion are listed below. -30 9/2 -1/2a) 8-6.24 x 10 cm erg for f - 1, and assuming imaginary...sise Lt La a moorfeW, coLlsmme Usmwu ad, La imma, sight be sopmed to 1ase wediaeto. tou~saie ~ the eve am bo -~atm tow Visions (YOLIM60 eg at, * .5

  13. Radiation 2006. In association with the Polymer Division, Royal Australian Chemical Institute. Incorporating the 21st AINSE Radiation Chemistry Conference and the 18th Radiation Biology Conference, conference handbook

    International Nuclear Information System (INIS)

    2006-04-01

    This conference facilitates a meeting of scientists and researchers to present and discuss their newest areas of research and investigation. It incorporates presentations on medical radiation therapies, biological effects of radiation, future areas of concern and nanotechnology

  14. Pioneer 10 and 11 Jovian encounters: radiation dose and biological lethality.

    Science.gov (United States)

    Miller, M W; Kaufman, G E; Maillie, H D

    1976-01-01

    In their recent Jupiter flybys Pioneer 10 and Pioneer 11 passed through a belt of intense particulate radiation. For Pioneer 10 the radiation dose on the craft's outer surface was at least 5 x 10(5) rads from electrons plus 1.0 x 10(6) rads from protons; the radiation dose inside the craft (0.3 cm aluminum) was approximately 4.5 x 10(5) rads. For Pioneer 11 the surface dose was at least 1.3 x 10(5) rads from electrons plus 3 x 10(5) rads from protons; the interior radiation dose was approximately 1.2 x 10(5) rads. Significant survival of microbial spores would be possible at these calculated doses; however, even the interior dose of Pioneer 11 would be lethal to man and most multicellular biological organisms.

  15. Biological effects of low-dose radiation on human population living in high-background radiation areas of Kerala coast

    International Nuclear Information System (INIS)

    Das, Birajalaxmi

    2016-01-01

    High-level natural radiation areas (HLNRA) of Kerala coast is densely populated and known for its wide variation in background radiation dose levels due to uneven distribution of monazite in the beach sand. The background radiation dose varies from 1 to 45 mGv/y. The areas with >1.5mGy/y is considered as HLNRA. Human population inhabiting in this area are exposed to low-dose chronic radiation since generations. Hence, this population provides an ideal situation to study dose response and adaptive response, if any, due to natural chronic low-dose exposure. It has been investigated extensively to study the biological and health effects of long-term low-dose/low-dose radiation exposure. So far over 150, 000 newborns monitored from hospital-based study did not reveal any significant difference in the incidence of any of the malformations and stillbirth between HLNRA and adjacent control areas. A case-control study on cleft lip/palate and mental retardation did not show any association with background radiation dose. Cytogenetic investigation of over 27,000 newborns did not show any significant increase in the frequency of chromosome aberrations and karyotype anomalies. DNA damage endpoints, such as micronuclei, telomere length and DNA strand breaks, did not reveal any significant difference between control and exposed population. Studies on DNA damage and repair revealed efficient repair of DNA strand breaks in HLNRA individuals. Molecular studies using high throughput microarray analysis indicated a large number of genes involved in various molecular and cellular pathways. Indications of in vivo radioadaptive response due to natural chronic low-dose exposure in this population have important implications to human health. (author)

  16. At the Crossroads of Cancer Stem Cells, Radiation Biology, and Radiation Oncology.

    Science.gov (United States)

    Gerweck, Leo E; Wakimoto, Hiroaki

    2016-03-01

    Reports that a small subset of tumor cells initiate and sustain tumor growth, are resistant to radiation and drugs, and bear specific markers have led to an explosion of cancer stem cell research. These reports imply that the evaluation of therapeutic response by changes in tumor volume is misleading, as volume changes reflect the response of the sensitive rather than the resistant tumorigenic cell population. The reports further suggest that the marker-based selection of the tumor cell population will facilitate the development of radiation treatment schedules, sensitizers, and drugs that specifically target the resistant tumorigenic cells that give rise to treatment failure. This review presents evidence that contests the observations that cancer stem cell markers reliably identify the subset of tumor cells that sustain tumor growth and that the marker-identified population is radioresistant relative to the marker-negative cells. Experimental studies show that cells and tumors that survive large radiation doses are not more radioresistant than unirradiated cells and tumors, and also show that the intrinsic radiosensitivity of unsorted colony-forming tumor cells, in combination with the fraction of unsorted tumor cells that are tumor initiating, predicts tumor radiocurability. ©2016 American Association for Cancer Research.

  17. Bibliographical database of radiation biological dosimetry and risk assessment: Part 1, through June 1988

    Energy Technology Data Exchange (ETDEWEB)

    Straume, T.; Ricker, Y.; Thut, M.

    1988-08-29

    This database was constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on publication number, authors, key words, title, year, and journal name. Photocopies of all publications contained in the database are maintained in a file that is numerically arranged by citation number. This report of the database is provided as a useful reference and overview. It should be emphasized that the database will grow as new citations are added to it. With that in mind, we arranged this report in order of ascending citation number so that follow-up reports will simply extend this document. The database cite 1212 publications. Publications are from 119 different scientific journals, 27 of these journals are cited at least 5 times. It also contains reference to 42 books and published symposia, and 129 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed among the scientific literature, although a few journals clearly dominate. The four journals publishing the largest number of relevant papers are Health Physics, Mutation Research, Radiation Research, and International Journal of Radiation Biology. Publications in Health Physics make up almost 10% of the current database.

  18. Bibliographical database of radiation biological dosimetry and risk assessment: Part 1, through June 1988

    International Nuclear Information System (INIS)

    Straume, T.; Ricker, Y.; Thut, M.

    1988-01-01

    This database was constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on publication number, authors, key words, title, year, and journal name. Photocopies of all publications contained in the database are maintained in a file that is numerically arranged by citation number. This report of the database is provided as a useful reference and overview. It should be emphasized that the database will grow as new citations are added to it. With that in mind, we arranged this report in order of ascending citation number so that follow-up reports will simply extend this document. The database cite 1212 publications. Publications are from 119 different scientific journals, 27 of these journals are cited at least 5 times. It also contains reference to 42 books and published symposia, and 129 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed among the scientific literature, although a few journals clearly dominate. The four journals publishing the largest number of relevant papers are Health Physics, Mutation Research, Radiation Research, and International Journal of Radiation Biology. Publications in Health Physics make up almost 10% of the current database

  19. Cellular response to ionizing radiations: a study of the roles of physics and biology

    International Nuclear Information System (INIS)

    DeWyngaert, J.K.

    1982-01-01

    A study of the complementary roles of physics and biology in determining the response of cellular systems to ionizing radiations has been conducted. Upon exposure to radiation, a cell responds in a binary (yes/no) manner in terms of its proliferative ability (survival). The relationship between the survival probability and absorbed dose may then be examined in terms of relevant physical and biological parameters. The approach to these studies was to vary the physics and biology independently and observe separately their influences upon the measured effect. Unique to these studies was the use of heterogeneous tumor systems. These are solid tumors found to consist of genetically related but identifiably distinct populations of cells. The two heterogeneous systems studied, a murine system consisting of four subpopulations and a human tumor system with two subpopulations, were exposed to graded doses of 14 MeV neutrons or x-rays and their effectiveness in inducing cell lethality compared. A further examination of the radiation effect involved a study at the chemical level, measuring the ability of oxygen to potentiate the damage produced by photon irradiation. To summarize, the physics, biology and the environment have all been varied, and the systematics of the responses studied. The data were analyzed within the formalisms of the dual theory of radiation action, the repair-misrepair model, and the repair saturation model of cell killing. The change in survival curve shape and the increased effectiveness in cell killing for higher Linear Energy Transfer (LET) radiations (neutrons vs. x-rays) are discussed in relation to explanations in terms of either physical or biochemical processes

  20. Response of biological uv dosimeters to the simulated extraterrestrial uv radiation

    Science.gov (United States)

    Bérces, A.; Rontó, G.; Kerékgyártó, T.; Kovács, G.; Lammer, H.

    In the Laboratory polycrystalline uracil thin layer and bacteriophage T7 detectors have been developed for UV dosimetry on the EarthSs surface. Exponential response of the uracil polycrystal has been detected both by absorption spectroscopy and measurements of the refractive index under the influence of terrestrial solar radiation or using UV-C sources. In UV biological dosimetry the UV dose scale is additive starting at a value of zero according to the definition of CIE (Technical Report TC-6-18). The biological dose can be defined by a measured end-effect. In our dosimeters (phage T7 and uracil dosimeter) exposed to natural (terrestrial) UV radiation the proportion of pyrimidin photoproducts among the total photoproducts is smaller than 0.1 and the linear correlation between the biological and physical dose is higher than 0.9. According to the experimental data this linear relationship is often not valid. We observed that UV radiation did not only induce dimerisation but shorter wavelengths caused monomerisation of pyrimidin dimers. Performing the irradiation in oxygen free environment and using a Deuterium lamp as UV source, we could increase monomerisation against dimerisation thus the DNA-based dosimetrySs additivity rule is not fulfilled in these conditions. In this study we will demonstrate those non-linear experiments which constitute the basis of our biological experiments on the International Space Station.

  1. Biological Effects of Sunlight, Ultraviolet Radiation, Visible Light, Infrared Radiation and Vitamin D for Health.

    Science.gov (United States)

    Holick, Michael F

    2016-03-01

    Humans evolved in sunlight and had depended on sunlight for its life giving properties that was appreciated by our early ancestors. However, for more than 40 years the lay press and various medical and dermatology associations have denounced sun exposure because of its association with increased risk for skin cancer. The goal of this review is to put into perspective the many health benefits that have been associated with exposure to sunlight, ultraviolet A (UVA) ultraviolet B (UVB), visible and infrared radiation. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  2. Biological effects of electromagnetic radiations - 7. International Conference, La Valette, Malta, 8-12 October 2012

    International Nuclear Information System (INIS)

    Demaret, P.

    2013-01-01

    This document proposes a synthesis of a conference on the biological effects of electromagnetic radiations. With reference to epidemiological studies, different issues have been addressed: pathological effects (either of static fields, or of extremely low frequencies, or of radio-frequencies), biological effects (methodological issues, case of extremely low frequencies and of radio-frequencies), medical applications of electromagnetic fields (tumour removal, neurological disorders, consolidation, wound healing and recovery), assessment of electromagnetic fields (existing directives and regulations, case of electric lines and of radio-frequencies), exposure to electromagnetic fields (occupational exposure in medical or industrial applications, specific devices such as telephones, regulation)

  3. A new model for biological effects of radiation and the driven force of molecular evolution

    Science.gov (United States)

    Wada, Takahiro; Manabe, Yuichiro; Nakajima, Hiroo; Tsunoyama, Yuichi; Bando, Masako

    We proposed a new mathematical model to estimate biological effects of radiation, which we call Whack-A-Mole (WAM) model. A special feature of WAM model is that it involves the dose rate of radiation as a key ingredient. We succeeded to reproduce the experimental data of various species concerning the radiation induced mutation frequencies. From the analysis of the mega-mouse experiments, we obtained the mutation rate per base-pair per year for mice which is consistent with the so-called molecular clock in evolution genetics, 10-9 mutation/base-pair/year. Another important quantity is the equivalent dose rate for the whole spontaneous mutation, deff. The value of deff for mice is 1.1*10-3 Gy/hour which is much larger than the dose rate of natural radiation (10- (6 - 7) Gy/hour) by several orders of magnitude. We also analyzed Drosophila data and obtained essentially the same numbers. This clearly indicates that the natural radiation is not the dominant driving force of the molecular evolution, but we should look for other factors, such as miscopy of DNA in duplication process. We believe this is the first quantitative proof of the small contribution of the natural radiation in the molecular evolution.

  4. The impact of advances in human molecular biology on radiation genetic risk estimation in man

    International Nuclear Information System (INIS)

    Sankaranarayanan, K.

    1996-01-01

    This paper provides an overview of the conceptual framework, the data base, methods and assumptions used thus far to assess the genetic risks of exposure of human populations to ionising radiation. These are then re-examined in the contemporary context of the rapidly expanding knowledge of the molecular biology of human mendelian diseases. This re-examination reveals that (i) many of the assumptions used thus far in radiation genetic risk estimation may not be fully valid and (ii) the current genetic risk estimates are probably conservative, but provide an adequate margin of safety for radiological protection. The view is expressed that further advances in the field of genetic risk estimation will be largely driven by advances in the molecular biology of human genetic diseases. (author). 37 refs., 5 tabs

  5. Characterization of Radiation Fields for Assessing Concrete Degradation in Biological Shields of NPPs

    Directory of Open Access Journals (Sweden)

    Remec Igor

    2017-01-01

    Full Text Available Life extensions of nuclear power plants (NPPs to 60 years of operation and the possibility of subsequent license renewal to 80 years have renewed interest in long-term material degradation in NPPs. Large irreplaceable sections of most nuclear generating stations are constructed from concrete, including safety-related structures such as biological shields and containment buildings; therefore, concrete degradation is being considered with particular focus on radiation-induced effects. Based on the projected neutron fluence values (E > 0.1 MeV in the concrete biological shields of the US pressurized water reactor fleet and the currently available data on radiation effects on concrete, some decrease in mechanical properties of concrete cannot be ruled out during extended operation beyond 60 years. An expansion of the irradiated concrete database is desirable to ensure reliable risk assessment for extended operation of nuclear power plants.

  6. Biological effects and physics of solar and galactic cosmic radiation, Part B; Proceedings of a NATO Advanced Study Institute on Biological Effects and Physics of Solar and Galactic Cosmic Radiation, Algarve, Portugal, Oct. 13-23, 1991

    Science.gov (United States)

    Swenberg, Charles E. (Editor); Horneck, Gerda (Editor); Stassinopoulos, E. G. (Editor)

    1993-01-01

    Since there is an increasing interest in establishing lunar bases and exploring Mars by manned missions, it is important to develop appropriate risk estimates and radiation protection guidelines. The biological effects and physics of solar and galactic cosmic radiation are examined with respect to the following: the radiation environment of interplanetary space, the biological responses to radiation in space, and the risk estimates for deep space missions. There is a need for a long-term program where ground-based studies can be augmented by flight experiments and an international standardization with respect to data collection, protocol comparison, and formulation of guidelines for future missions.

  7. Biological effects and radiation protection in veterinary radiology: a literature review

    International Nuclear Information System (INIS)

    Rosa, P.C.; Siqueira, D.; Barros, F.S.

    2017-01-01

    Veterinary radiology is a tool of excellent diagnostic support. Besides X--ray, it counts on technological advances such as computed tomography, nuclear medicine and interventional radiology . It is common during X-ray practice to use exposure parameters with short times to avoid blurring by the movement of the animal, but the fact that the animals need to be immobilized during the exposures contribute significantly with the increase of the dose received by the professionals, whose biological risks are not yet well established as a result of exposure to other factors harmful to health, such as anesthetic gases, insecticides, zoonoses and others. For this reason, we sought to verify the main radiological risks to which veterinarians are exposed and the best means to guarantee radiological protection

  8. Spectroscopic research of interaction between pulsed laser radiation and some biological objects

    Science.gov (United States)

    Loschenov, Victor B.; Betin, A. J.; Volkova, Anna I.; Konov, Vitali I.; Kramarenko, T. A.; Silenok, Alexander S.

    1990-09-01

    This research is dedicated to spectral analysis methods of i&raction of high enerciy laser radiation with biological objects like humain vessel affected by atheroscie rosis (investigated immediately after its surgical removal) and gallstones of diffe rent kinds. In our work ie used laser sources jithA3fl8 nm (Eximer laser Xe-Cl), A532 nm andlO64 nm ( YAG:Nd3).

  9. Current status of biological indicators to detect and quantify previous exposures to radiation

    International Nuclear Information System (INIS)

    Lushbaugh, C.; Eisele, G.; Burr, W. Jr.; Hubner, K.; Wachholz, B.

    1991-01-01

    As noted in the text of this paper, immunological concepts are in a state of rapid development, and it is possible that improved methods for applying immunologic procedures as biological indicators of radiation may be developed in the future. However, at the present time, immunological indicators are not useful, even in an early time period, for quantitating radiation dose after total-body irradiation. A semiquantitative effect is observable in the early phase after total-body irradiation over a period of days to weeks, but there is little data available to indicate whether any of the immunological parameters can be indicative of a dose when the test is applied several years after radiation exposure. More detailed information regarding immunological indicators for estimating irradiation dose has been summarized elsewhere

  10. Applications of Synchrotron Radiation Micro Beams in Cell Micro Biology and Medicine

    CERN Document Server

    Ide-Ektessabi, Ari

    2007-01-01

    This book demonstrates the applications of synchrotron radiation in certain aspects of cell microbiology, specifically non-destructive elemental analyses, chemical-state analyses and imaging (distribution) of the elements within a cell. The basics for understanding and applications of synchrotron radiation are also described to make the contents easier to be understood for a wide group of researchers in medical and biological sciences who might not be familiar with the physics of synchrotron radiation. The two main techniques that are discussed in this book are the x-ray fluorescence spectroscopy (XRF) and the x-ray fine structure analysis (XAFS). Application of these techniques in investigations of several important scientific fields, such as neurodegeneration and other diseases related to cell malfunctioning, are demonstrated in this book.

  11. Epigenetics Meets Radiation Biology as a New Approach in Cancer Treatment

    Directory of Open Access Journals (Sweden)

    Joo Mi Yi

    2013-07-01

    Full Text Available Cancer is a disease that results from both genetic and epigenetic changes. In recent decades, a number of people have investigated the disparities in gene expression resulting from variable DNA methylation alteration and chromatin structure modification in response to the environment. Especially, colon cancer is a great model system for investigating the epigenetic mechanism for aberrant gene expression alteration. Ionizing radiation (IR could affect a variety of processes within exposed cells and, in particular, cause changes in gene expression, disruption of cell cycle arrest, and apoptotic cell death. Even though there is growing evidence on the importance of epigenetics and biological processes induced by radiation exposure in various cancer types including colon cancer, specific epigenetic alterations induced by radiation at the molecular level are incompletely defined. This review focuses on discussing possible IR-mediated changes of DNA methylation and histone modification in cancer.

  12. Radiation effects analysis in a group of interventional radiologists using biological and physical dosimetry methods

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, M., E-mail: WEMLmirapas@iqn.upv.e [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Montoro, A.; Almonacid, M. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Ferrer, S. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Barquinero, J.F. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Tortosa, R. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Verdu, G. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Rodriguez, P. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Barrios, L.L. [Department of Physiology and Cellular Biology, Unit of Cellular Biology (UAB) (Spain); Villaescusa, J.I. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain)

    2010-08-15

    Interventional radiologists and staff members are frequently exposed to protracted and fractionated low doses of ionizing radiation, which extend during all their professional activities. These exposures can derive, due to the effects of direct and scattered radiation, in deterministic effects (radiodermitis, aged skin, cataracts, telangiectasia in nasal region, vasocellular epitelioms, hands depilation) and/or stochastic ones (cancer incidence). A methodology has been proposed for estimating the radiation risk or detriment from a group of six exposed interventional radiologists of the Hospital Universitario La Fe (Valencia, Spain), which had developed general exposition symptoms attributable to deterministic effects of ionizing radiation. Equivalent doses have been periodically registered using TLD's and wrist dosimeters, H{sub p}(10) and H{sub p}(0.07), respectively, and estimated through the observation of translocations in lymphocytes of peripheral blood (biological methods), by extrapolating the yield of translocations to their respective dose-effect curves. The software RADRISK has been applied for estimating radiation risks in these occupational radiation exposures. This software is based on transport models from epidemiological studies of population exposed to external sources of ionizing radiation, such as Hiroshima and Nagasaki atomic bomb survivors [UNSCEAR, Sources and effects of ionizing radiation: 2006 report to the general assembly, with scientific annexes. New York: United Nations; 2006]. The minimum and maximum average excess ratio for skin cancer has been, using wrist physical doses, of [1.03x10{sup -3}, 5.06x10{sup -2}], concluding that there is not an increased risk of skin cancer incidence. The minimum and maximum average excess ratio for leukemia has been, using TLD physical doses, of [7.84x10{sup -2}, 3.36x10{sup -1}], and using biological doses, of [1.40x10{sup -1}, 1.51], which is considerably higher than incidence rates, showing an

  13. Harmful Algal Blooms (HABs)

    Science.gov (United States)

    ... toxins that may harm or kill fish and marine animals. Humans who eat shellfish contaminated with HAB toxins ... toxins that may harm or kill fish and marine animals. Humans who eat shellfish containing toxins produced by ...

  14. Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO

    Science.gov (United States)

    Cucinotta, F. A.; Wilson, J. W.; Williams, J. R.; Dicello, J. F.

    2000-01-01

    We compare models of radiation transport and biological response to physical and biological dosimetry results from astronauts on the Mir space station. Transport models are shown to be in good agreement with physical measurements and indicate that the ratio of equivalent dose from the Galactic Cosmic Rays (GCR) to protons is about 3/2:1 and that this ratio will increase for exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cells; a track-structure model and the linear-quadratic model with linear energy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement with data for aberrations in lymphocytes of Mir crew members: however there are differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major difference in the models is the increased effectiveness predicted by the track model for low charge and energy ions with LET near 10 keV/micrometers. The results of our calculations indicate that aluminum shielding, although providing important mitigation of the effects of trapped radiation, provides no protective effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measure until about 100 g/cm 2 of material is used.

  15. Future development of biological understanding of radiation protection: implications of nonstochastic effects

    International Nuclear Information System (INIS)

    Hahn, F.F.; McClellan, R.O.; Boecker, B.B.; Muggenburg, B.A.

    1988-01-01

    Radiation-protection standards are based on minimizing or preventing biological effects in exposed populations. Radiation-induced biological effects can be classified as stochastic--malignant and hereditary diseases for which the probability of an effect occurring is a function of dose without threshold--and nonstochastic--inflammatory and degenerative diseases for which the severity and frequency of the effect varies with the dose and for which a threshold is present. The current International Commission on Radiation Protection (ICRP) approach for setting limits for intakes of radionuclides by workers, which accounts for doses to significantly exposed organs of the body, is based on limitation of stochastic effects in most situations. When setting exposure limits, nonstochastic effects are generally considered to be unlikely at the limits for stochastic effects. In some situations, limits based on prevention of nonstochastic effects are lower than for stochastic effects. This review considers the threshold radiation doses for thyroid, bone, liver and lung and their relationship to the limits recommended by the ICRP and the cancer risks at the limits. This review indicates that the threshold dose for nonstochastic effects in thyroid and lung is much above the dose limit as advocated by ICRP. The threshold dose for nonstochastic effects in bone and liver is much closer to the dose limit, but protection from nonstochastic effects should still be afforded by the dose limits

  16. Systems Biology Modeling of the Radiation Sensitivity Network: A Biomarker Discovery Platform

    International Nuclear Information System (INIS)

    Eschrich, Steven; Zhang Hongling; Zhao Haiyan; Boulware, David; Lee, Ji-Hyun; Bloom, Gregory; Torres-Roca, Javier F.

    2009-01-01

    Purpose: The discovery of effective biomarkers is a fundamental goal of molecular medicine. Developing a systems-biology understanding of radiosensitivity can enhance our ability of identifying radiation-specific biomarkers. Methods and Materials: Radiosensitivity, as represented by the survival fraction at 2 Gy was modeled in 48 human cancer cell lines. We applied a linear regression algorithm that integrates gene expression with biological variables, including ras status (mut/wt), tissue of origin and p53 status (mut/wt). Results: The biomarker discovery platform is a network representation of the top 500 genes identified by linear regression analysis. This network was reduced to a 10-hub network that includes c-Jun, HDAC1, RELA (p65 subunit of NFKB), PKC-beta, SUMO-1, c-Abl, STAT1, AR, CDK1, and IRF1. Nine targets associated with radiosensitization drugs are linked to the network, demonstrating clinical relevance. Furthermore, the model identified four significant radiosensitivity clusters of terms and genes. Ras was a dominant variable in the analysis, as was the tissue of origin, and their interaction with gene expression but not p53. Overrepresented biological pathways differed between clusters but included DNA repair, cell cycle, apoptosis, and metabolism. The c-Jun network hub was validated using a knockdown approach in 8 human cell lines representing lung, colon, and breast cancers. Conclusion: We have developed a novel radiation-biomarker discovery platform using a systems biology modeling approach. We believe this platform will play a central role in the integration of biology into clinical radiation oncology practice.

  17. The SCID-hu mouse and its application to human radiation biology

    International Nuclear Information System (INIS)

    Kyoizumi, Seishi; Akiyama, Mitoshi; McCune, J.M.; Namikawa, Reiko.

    1993-01-01

    The radiobiological study of humans has been hampered by a lack of suitable in vivo experimental models. Of course, acute and chronic radiation effects in humans have been documented in the studies of atomic bomb (A-bomb) survivors and patients irradiated either by therapeutic intent or by accident. However, the information gained from these studies has been limited by the difficulties in estimating precise radiation doses and in obtaining biological samples for directly analyzing the processes of radiation-induced pathogenesis. With these issues in mind, we propose that the severe combined immunodeficient mouse-human chimera can be used as an in vivo experimental model for human radiation biology. We have developed techniques by which normal human bone marrow can be implanted into immunodeficient C.B-17 scid/scid (SCID) mice (S. Kyoizumi et al, Blood 79, 1704, 1992). We have report that this in vivo model can be used for the analysis of radiation damage to human bone marrow. After whole-body irradiation of the engrafted animals, human progenitor cells within the human marrow were destroyed in a dose-dependent manner (D 0 = 0.7-1.0Gy, n = 1.0). Acute hematotoxicity was reduced when the radioprotective agent (WR-2721) was administered prior to irradiation. After low dose irradiation, the recovery of human progenitor activity was accelerated by treatment with human granulocyte-colony stimulating factor (G-CSF). This small animal model may prove amenable for the risk analysis of human radiation exposure as well as for the development of new modalities for the prevention and treatment of radiotoxic damage to the human hematopoietic system. (author)

  18. Effects of radio frequency identification-related radiation on in vitro biologics.

    Science.gov (United States)

    Uysal, Ismail; Hohberger, Clive; Rasmussen, R Scott; Ulrich, David A; Emond, Jean-Pierre; Gutierrez, Alfonso

    2012-01-01

    The recent developments on the use of e-pedigree to identify the chain of custody of drugs suggests the use of advanced track and trace technologies such as two-dimensional barcodes and radio frequency identification (RFID) tags. RFID technology is used mainly for valuable commodities such as pharmaceutical products while incorporating additional functionalities like monitoring environmental variables to ensure product safety and quality. In its guidance for the use of RFID technologies for drugs (Compliance Policy Guide Section 400.210), the Food and Drug Administration outlined multiple parameters that would apply to any study or application using RFID. However, drugs approved under a Biologics License Application or protein drugs covered by a New Drug Application were excluded mainly due to concerns about the effects of radio frequency radiation (thermal and/or non-thermal) on biologics. Even though the thermal effects of radio frequency on biologics are relatively well understood, there are few studies in the literature about the non-thermal effects of radio frequency with regards to the protein structure integrity. In this paper, we analyze the non-thermal effects of radio frequency radiation by exposing a wide variety of biologics including biopharmaceuticals with vaccines, hormones, and immunoglobulins, as well as cellular blood products such as red blood cells and whole blood-derived platelets as well as fresh frozen plasma. In order to represent the majority of the frequency spectrum used in RFID applications, five different frequencies (13.56 MHz, 433 MHz, 868 MHz, 915 MHz, and 2.4 GHz) are used to account for the most commonly used international frequency bands for RFID. With the help of specialized radio frequency signal-generating hardware, magnetic and electromagnetic fields are created around the exposed products with power levels greater than Federal Communications Commission-regulated limits. The in vitro test results on more than 100

  19. [Harmful algae and health].

    Science.gov (United States)

    Kankaanpää, Harri T

    2011-01-01

    Harmful algae are a worldwide problem. Phycotoxins is a general term for toxic compounds produced by harmful species of the phytoplankton. This review deals with the occurrence of harmful algae and phycotoxins in the Baltic Sea and other domestic waters, the ways of getting exposed to them, and their effects. Advice on how to avoid the exposure is provided.

  20. Quantum solid state mechanisms of biological effects of electromagnetic radiation with emphasis on local superconductivity

    Science.gov (United States)

    Achimowicz, J.

    1982-01-01

    The aim of the paper is to review quantum solid state mechanisms of nonthermal (specific) bioeffects of nonionizing radiation and to present the author's own hypothesis concerning mechanisms based on biological superconductivity. Classical and quantum mechanisms of bioeffects are compared stressing the necessity of not only considering quantum absorption, transfer, and conversion of radiation energy in biological systems, but also of appropriate systems modeling. The need is stressed for developing quantum models of the biological solid state on the supramolecular level to fill the gap between molecular and cell biology. The supramolecular models of macromolecules and enzyme complexes will be reviewed. The high-temperature superconductivity problem in organic systems will be discussed with stress on the importance of system structure and the excitation quasi-particle (phonon and electron) spectra relationship. New mechanisms of enzymatic activity assuming enzyme-substrate complex electron spectrum instability induced by electron- and phonon-mediated electron-electron interaction are proposed. Since this quantum cooperative phenomenon is the possible origin of specificity and efficiency of enzyme action it is extremely sensitive to system-generated electromagnetic fields, which gives the possibility of enzymatic regulation and also may explain some nonthermal resonant bioeffects. Local superconductivity (coherent electron states) and Josephson effects as the possible mechanisms of bioeffects are discussed.

  1. Biological effect of radiation. Basis for understanding the risk of Fukushima nuclear accident

    International Nuclear Information System (INIS)

    Imaoka, Tatsuhiko

    2011-01-01

    The radionuclide release in the Fukushima Nuclear Accident has induced a tremendous anxiety on possible health effects of low dose radiation. When radiation hits a cell in an organism, it may induce DNA damages which, if not repaired properly, lead to either cell death or genetic mutation. If function of the tissue is lost as a result of cell death, various tissue responses including dysfunction of hematopoietic tissues, sterility and skin responses may occur; these responses are not manifested if the radiation dose is low enough. Genetic mutation is considered to occur, albeit at a low frequency, even if the radiation dose is very small. Cancer is a result of genetic mutation and its probability is considered to rise, albeit slightly, if radiation induces a small amount of additional mutations. These assumptions lead to a notion that there is no 'safety dose' below which radiation does not cause any cancer. On the other hand, the study of atomic bomb survivors of Hiroshima and Nagasaki provides the most reliable quantitative information on the relationship between radiation dose and accompanying increase in cancer risk. The analysis so far indicates that cancer risk increases by 0.5-fold, compared to a background level, if a human body is exposed to 1 sievert of radiation; at lower doses, the risk is proportional to the dose, but it is impossible to detect cancer risk associated with 100 milli sievert of exposure because of statistical limitations. Although exposure to atomic bomb radiation occurred in a very little instance, the current situation poses a prolonged (i.e., low dose rate) exposure, probably resulting in still lower cancer risk. Still, since current radiation exposure has no benefit, unlike that in medical situations, it is important to reduce it to a level as low as reasonably achievable. I will explain the biological effect of radiation, including its mechanistic basis and effects on the human body, and wish to help the audience to

  2. Carbon Heavy-ion Radiation Induced Biological effects on Oryza sativa L.

    Science.gov (United States)

    Zhang, Meng; Sun, Yeqing; Li, Xishan; Gong, Ning; Meng, Qingmei; Liu, Jiawei; Wang, Ting

    2016-07-01

    Large number of researches on rice after spaceflights indicated that rice was a favorable model organism to study biological effects induced by space radiation. The stimulative effect could often be found on rice seedlings after irradiation by low-dose energetic heavy-ion radiation. Spaceflight also could induce stimulative effect on kinds of seeds. To further understand the mechanism of low-dose radiation biological effects and the dose range, the germinated rice seeds which were irradiated by different doses of carbon heavy-ion (0, 0.02, 0.1, 0.2, 1, 2, 5, 10, 15 and 20Gy, LET=27.3keV/µm) were used as materials to study. By investigating the variation of rice phenotype under different doses, we found that 2Gy radiation dose was a dividing point of the phenotypic variation. Transmission electron microscopy was used to observe the variation of mitochondria, chloroplast, endoplasmic reticulum, ribosome and nucleus in mesophyll cell of rice apical meristem at 24 hours after radiation with different doses. The cells were not apparently physiologically damaged when the dose of radiation was less than 2Gy. The number of chloroplast did not change significantly, but the number of mitochondria was significantly increased, and gathered around in the chloroplast and endoplasmic reticulum; the obvious lesion of chloroplast and mitochondria were found at the mesophyll cells when radiation dose was higher than 2Gy. The mitochondria were swelling and appearing blurred crest. The chloroplast and mitochondrial mutation rate increased significantly (p<0.01). These phenomena showed that cell biological changes may be the reasons of the stimulation and inhibition effects with the boundary of 2Gy. Since mitochondrial was an important organelle involved in the antioxidative systems, its dysfunction could result in the increase of reactive oxygen species and lipid peroxidation. We found that the growth stimulation induced by low-dose radiation mainly occurred at three-leaf stage along

  3. Biological effects of in vitro THz radiation exposure in human foetal fibroblasts.

    Science.gov (United States)

    De Amicis, Andrea; Sanctis, Stefania De; Cristofaro, Sara Di; Franchini, Valeria; Lista, Florigio; Regalbuto, Elisa; Giovenale, Emilio; Gallerano, Gian Piero; Nenzi, Paolo; Bei, Roberto; Fantini, Massimo; Benvenuto, Monica; Masuelli, Laura; Coluzzi, Elisa; Cicia, Cristina; Sgura, Antonella

    2015-11-01

    In recent years, terahertz (THz) radiation has been widely used in a variety of applications: medical, security, telecommunications and military areas. However, few data are available on the biological effects of this type of electromagnetic radiation and the reported results, using different genetic or cellular assays, are quite discordant. This multidisciplinary study focuses on potential genotoxic and cytotoxic effects, evaluated by several end-points, associated with THz radiation. For this purpose, in vitro exposure of human foetal fibroblasts to low frequency THz radiation (0.1-0.15THz) was performed using a Compact Free Electron Laser. We did not observe an induction of DNA damage evaluated by Comet assay, phosphorylation of H2AX histone or telomere length modulation. In addiction, no induction of apoptosis or changes in pro-survival signalling proteins were detected. Moreover, our results indicated an increase in the total number of micronuclei and centromere positive micronuclei induction evaluated by CREST analysis, indicating that THz radiation could induce aneugenic rather than clastogenic effects, probably leading to chromosome loss. Furthermore, an increase of actin polymerization observed by ultrastructural analysis after THz irradiation, supports the hypothesis that an abnormal assembly of spindle proteins could lead to the observed chromosomal malsegregation. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Transient impedance changes in venous endothelial monolayers as a biological radiation dosimetry response

    Directory of Open Access Journals (Sweden)

    Erik Fossum Young

    2012-10-01

    Full Text Available In March of 2011, a magnitude 9.0 earthquake and subsequent 14 m-high tsunami caused major damage to the Fukushima Daiichi nuclear power plant in Japan.  While cancer incidence in the radiation-exposed population is a logical concern, the complex effects of radiation on the heart and cardiovascular system are also of interest.  Immediate and early vascular radiation effects could be exploited as a dosimetry modality.  To test whether non-coronary vasculature exhibited transient perturbation in barrier function, video microscopy studies and Electric Cell Substrate Impedance Sensing technology were used to probe very subtle changes in primary human vascular endothelium.  Human umbilical vein endothelial cell (HUVEC monolayers exhibit a transient, statistically significant decrease (P = 0.017 in monolayer resistance 3 h after irradiation with 5.0 Gy of g rays.  Radiation induced perturbations in HUVEC monolayer permeability are similar in magnitude and kinetics to those observed in coronary arterial endothelium.  Therefore, at least two types of vasculature respond to radiation on ECIS arrays with an early transient disruption in permeability.  The finding supports the use of early passage HUVECs for use in bioelectric dosimetry studies of vasculature and suggests that permeability of vessels could potentially serve as a biological dosimetry tool.

  5. Biologically-based mechanistic models of radiation-related carcinogenesis applied to epidemiological data.

    Science.gov (United States)

    Rühm, Werner; Eidemüller, Markus; Kaiser, Jan Christian

    2017-10-01

    Biologically-based mechanistic models that are used in combining current understanding of human carcinogenesis with epidemiological studies were reviewed. Assessment was made of how well they fit the data, whether they account for non-linear radiobiological low-dose effects, and whether they suggest any implications for the dose response at low doses and dose rates. However, the present paper does not make an attempt to provide a complete review of the existing literature on biologically-based models and their application to epidemiological data. In most studies the two-stage clonal expansion (TSCE) model of carcinogenesis was used. The model provided robust estimates of identifiable parameters and radiation risk. While relatively simple, it is flexible, so that more stages can easily be added, and tests made of various types of radiation action. In general, the model performed similarly or better than descriptive excess absolute and excess relative risk models, in terms of quality of fit and number of parameters. Only very rarely the shape of dose-response predicted by the models was investigated. For some tumors, when more detailed biological information was known, additional pathways were included in the model. The future development of these models will benefit from growing knowledge on carcinogenesis processes, and in particular from use of biobank tissue samples and advances in omics technologies. Their use appears a promising approach to investigate the radiation risk at low doses and low dose rates. However, the uncertainties involved are still considerable, and the models provide only a simplified description of the underlying complexity of carcinogenesis. Current assumptions in radiation protection including the linear-non-threshold (LNT) model are not in contradiction to what is presently known on the process of cancer development.

  6. Bibliographical database of radiation biological dosimetry and risk assessment: Part 2

    International Nuclear Information System (INIS)

    Straume, T.; Ricker, Y.; Thut, M.

    1990-09-01

    This is part 11 of a database constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on authors, key words, title, year, journal name, or publication number. Photocopies of the publications contained in the database are maintained in a file that is numerically arranged by our publication acquisition numbers. This volume contains 1048 additional entries, which are listed in alphabetical order by author. The computer software used for the database is a simple but sophisticated relational database program that permits quick information access, high flexibility, and the creation of customized reports. This program is inexpensive and is commercially available for the Macintosh and the IBM PC. Although the database entries were made using a Macintosh computer, we have the capability to convert the files into the IBM PC version. As of this date, the database cites 2260 publications. Citations in the database are from 200 different scientific journals. There are also references to 80 books and published symposia, and 158 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed within the scientific literature, although a few journals clearly predominate. The journals publishing the largest number of relevant papers are Health Physics, with a total of 242 citations in the database, and Mutation Research, with 185 citations. Other journals with over 100 citations in the database, are Radiation Research, with 136, and International Journal of Radiation Biology, with 132

  7. Deliberate Self Harm Behavior

    Directory of Open Access Journals (Sweden)

    Fatma Gul Helvaci Celik

    2017-06-01

    Full Text Available The deliberate self-harm behaviour which defined as attempting to own body resulting in tisue damage without conscious desire of peolple to die, is a major public health problem worldwide. The causes of deliberate self- harm, risk factors, the relationship between mental disorders and treatment strategies are not fully known. Deliberate self- harm can be observed together with psychiatric disorders such as borderline personality disorder, histrionic personality disorder, eating disorders and mood disorders. Also, deliberate self-harm must be distinguished from suicidal behavior. Psychologi-cal trauma has been suggested as a risk factor for deliberate self- harm behavior. Trauma and traumatic events have long been associated with deliberate self- harm behavior. The aim of this review article is to investigate the etiology and epidemiology of deliberate self-harm behaviour and relationship between psychiatric disorders. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2017; 9(2.000: 209-226

  8. Beneficial radiation?

    International Nuclear Information System (INIS)

    Roth, E.; Feinendegen, E.

    1996-01-01

    Ionizing radiation is harmful and may cause cancer, as is well known. However, again and again, low doses of ionizing radiation, under certain conditions, are said to have beneficial effects on human health and, in particular, may reduce the cancer rate. This effect, which is discussed controversially in the technical and scientific literature, is called 'hormesis'. Studies of possible positive effects of ionizing radiation are becoming increasingly more important in scientific research. The article is an attempt to show, by the model case of cancer, under what conditions such positive health effects can occur, at least in principle, and will also contain rough plausibility assessments of the existence of such conditions. Aspects not covered include other existing or presumed positive biological effects of ionizing radiation, such as acceleration of growth, or general increase in the life expectancy of organisms. Also genetic damage will not be discussed in greater detail, despite the existence of some parallels with cancer, both cases constituting lesions to the genetic material of the cells, in one case, germ cells and, in the case of cancer, somatic cells. Also, acute radiation effect will be excluded which occur only at high radiation doses and, as such, always cause damage which, in therapeutic application to cancer, may again be lifesaving. It should be emphasized that the article is limited to a greatly restricted range of biological effects of ionizing radiation which, consequently, are of limited value for overall assessment. (orig.) [de

  9. Radiation protection in nuclear reactors

    International Nuclear Information System (INIS)

    El-Ashkar, Mohamed

    2008-01-01

    Full text: People are exposed to ionizing radiation in many different forms: cosmic rays that penetrate earth atmosphere or radiation from soil and mineral resources are natural forms of ionizing radiation. Other forms are produced artificially using radioactive materials for various beneficial applications in medicine, industry and other fields. The greatest concerns about ionizing radiation are tied to its potential health effects and a system of radiation protection has been developed to protect people from harmful radiation. The promotion of radiation protection is one of the International Atomic Energy Agency main activities. Radiation protection concerns the protection of workers, members of public, and patients undergoing diagnosis and therapy against the harmful effects of ionizing radiation. The report covers the responsibility of radiation protection officer in Egypt Second Research Reactor (ETRR-2) in Inshas - Egypt, also presents the protection against ionizing radiation from external sources, including types of radiation, sources of radiation (natural - artificial), and measuring units of dose equivalent rate. Also covers the biological effects of ionizing radiation, personal monitoring and radiation survey instruments and safe transport of radioactive materials. The report describes the Egypt Second Research Reactor (ETRR-2), the survey instruments used, also presents the results obtained and gave a relations between different categories of data. (author)

  10. The REPAIR Project: Examining the Biological Impacts of Sub-Background Radiation Exposure within SNOLAB, a Deep Underground Laboratory.

    Science.gov (United States)

    Thome, Christopher; Tharmalingam, Sujeenthar; Pirkkanen, Jake; Zarnke, Andrew; Laframboise, Taylor; Boreham, Douglas R

    2017-10-01

    Considerable attention has been given to understanding the biological effects of low-dose ionizing radiation exposure at levels slightly above background. However, relatively few studies have been performed to examine the inverse, where natural background radiation is removed. The limited available data suggest that organisms exposed to sub-background radiation environments undergo reduced growth and an impaired capacity to repair genetic damage. Shielding from background radiation is inherently difficult due to high-energy cosmic radiation. SNOLAB, located in Sudbury, Ontario, Canada, is a unique facility for examining the effects of sub-background radiation exposure. Originally constructed for astroparticle physics research, the laboratory is located within an active nickel mine at a depth of over 2,000 m. The rock overburden provides shielding equivalent to 6,000 m of water, thereby almost completely eliminating cosmic radiation. Additional features of the facility help to reduce radiological contamination from the surrounding rock. We are currently establishing a biological research program within SNOLAB: Researching the Effects of the Presence and Absence of Ionizing Radiation (REPAIR project). We hypothesize that natural background radiation is essential for life and maintains genomic stability, and that prolonged exposure to sub-background radiation environments will be detrimental to biological systems. Using a combination of whole organism and cell culture model systems, the effects of exposure to a sub-background environment will be examined on growth and development, as well as markers of genomic damage, DNA repair capacity and oxidative stress. The results of this research will provide further insight into the biological effects of low-dose radiation exposure as well as elucidate some of the processes that may drive evolution and selection in living systems. This Radiation Research focus issue contains reviews and original articles, which relate to the

  11. A literature survey of the biological effects and mechanics of electromagnetic radiation

    International Nuclear Information System (INIS)

    Zeh, K.A.

    1985-01-01

    The following report discusses the very controversial subject of electromagnetic interaction with the human body. The project was undertaken in the form of a literature survey to investigate the biological mechanisms responsible for the interaction, the theoretical models and associated mathematical techniques required to model the human body, the resulting energy deposition in the human and the factors which effect this. It was established that at present the most realistic model of man can be obtained using a block model and moment method technique with improved methods such as conjugate gradients or band approximation for the necessary matrix inversion. The impedance method of modelling could be very promising for future research. From the literature studied on biological effects no scientific evidence was found which definitely proves or disproves hazardous effects exist at low field intensities ( -2 ). The testes and the lens of the eye can be harmed, however, if the intensity is sufficient to cause a temperature rise of 1 degree Celsius in these organs

  12. Evaluation of the processing of dry biological ferment for gamma radiation

    International Nuclear Information System (INIS)

    Sabundjian, Ingrid Traete

    2007-01-01

    The developed work had with objectives to demonstrate if it had alteration in the growth of UFC in plate and in the viability of yeasts and total bacteria when dry biological ferment was dealt with by different doses to gamma radiation and under different times storage, to determine the D10 dose for total bacteria and yeasts in this product and to analyzed the processing of this product it promoted some benefit without causing unfeasibility of exactly. The different samples of dry biological ferment had been irradiated at IPEN in a Gammacell - 220 source at 0.5; 1; 2 and 3 kGy doses (dose rate of 3.51 kGy/h). This procedure referring samples to each dose of radiation had been after destined to the microbiological analysis and the test of viability while excessively the samples had been stored the ambient temperature (23 degree C). The increase of the dose of radiation caused a reduction in the counting of yeasts growth, of total bacteria growth and also in the frequency of viable yeast cells, demonstrated by FDA-EB fluorescent method. Beyond of radiation the storage time also it influenced in counting reduction of total bacteria and reduction of frequency of viable cells. According with the analysis of simple linear regression, the dose of radiation necessary to eliminate 90% of the yeast population was between 1.10 and 2.23 kGy and for the bacterial population varied between 2.31 and 2.95 kGy. These results demonstrated clearly the negative points of the application of ionizing radiation in dry biological ferment; therefore the interval of D10 found for total bacteria is superior to found for yeasts. Being thus, the use of this resource for the improvement of the product quality becomes impracticable, since to reduce significantly the bacterial population necessarily we have that to diminish the population of yeasts. With yeasts reduction of we will go significantly to modify the quality and the viability of product. (author)

  13. Gamma radiation effect on biological activity and enzymatic properties of snake venoms

    International Nuclear Information System (INIS)

    Herrera, E.; Yarleque, A.; Campos, S.; Zavaleta, A.

    1986-01-01

    The effect of gamma radiation, from Co-60, on the biological activity and on some enzymatic activities, present in the venoms of Lachesis muta and Bothrops atrox, using samples of dried venom that had been irradiated at a dose of 0.1, 0.5 and 1.0 Mrad have been studied. Variations in the degree of hemorrhage and local necrosis were observed in albino mice injected subcutaneously with venoms of both types. The reduction of the biological activity was greater for the local hemorrhagic effect and was dependent on the doses of irradiation. The specific activity of various enzymes, present in both venoms, is affected by the gamma radiation, at a dose of 0.1 Mrad the order of increasing inactivation being: exonuclease (4%), phospholipase (24%), caseinolytic enzyme (20%), tamesterase (33%), a thrombine-like enzyme (40%), fibrinolytic enzyme (41%), 5'-nucleotidase (50%) and endonuclease (55%). The enzymatic inactivation was augmented by 0.5 and 1.0 Mrad, without maintaining an arithmetic relation. The enzyme of major resistance to the radiation was exonuclease, whereas 5'-nucleotidase and endonuclease were the most sensitive. No significant changes were observed in the spectrum of UV absorbtion (range 260 to 290 nm) nor in the contents of L-tyrosine in the irradiated venoms

  14. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes

    International Nuclear Information System (INIS)

    Menz, R.; Andres, R.; Larsson, B.; Ozsahin, M.; Crompton, N.E.A.; Trott, K.

    1997-01-01

    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% ± 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. (orig.)

  15. A perspective on dose limits and biological effects of radiation on the foetus

    International Nuclear Information System (INIS)

    Myers, D.K.; Gordon, K.

    1992-01-01

    The potential biological effects of radiation doses to pregnant workers consistent with Canadian regulations and ICRP recommendations are reviewed. These hazards are in general very small compared to the normal hazards associated with human development. Potential carcinogenic effects may well be the major biological problem associated with foetal exposures. Radiation hazards to the embryo are essentially zero for exposures occurring during the first four weeks after conception. The new ICRP recommendations on exposures of pregnant women suggest a number of problems to be solved. These include (a) improvements in current methods of measuring both external radiation doses and intakes of certain radionuclides in Canada, (b) further research on the metabolism of radionuclides in pregnant women, including concentrations of certain radionuclides in foetal/embryonic tissues and also in adjacent tissues of the mother; and (c) socio-economic problems that may be involved in the implementation of the recommendations on exposures of pregnant workers, particularly in small facilities such as nuclear medicine departments in hospitals. (Author) 3 tabs., 21 refs

  16. Biological Effects of Ionising Radiation and Countermeasures (Les effets biologiques des rayonnements ionisants et leurs contre-mesures)

    Science.gov (United States)

    2018-01-01

    blood of pet dogs living in areas highly contaminated by organochlorine pesticides [10]. Aim: • To evaluate the effectiveness of using military...REPORT TR-HFM-222 Biological Effects of Ionising Radiation and Countermeasures (Les effets biologiques des rayonnements ionisants et leurs contre...REPORT TR-HFM-222 Biological Effects of Ionising Radiation and Countermeasures (Les effets biologiques des rayonnements ionisants et leurs contre

  17. Biological effects of exposure to non-ionising electromagnetic fields and radiation: III radiofrequency and microwave radiation

    International Nuclear Information System (INIS)

    Saunders, R.D.; Kowalczuk, C.I.; Sienkiewicz, Z.J.

    1991-12-01

    The biological effects of experimental exposure to radiofrequency (RF) and microwave radiation above 100 kHz are reviewed with the intention of providing a summary of effects directly relevant to considerations of the health and safety of exposed people. The biological bases for restricting exposures are also briefly discussed. Studies of the possible effects of electromagnetic field exposure on human populations are described in a separate report. The majority of the biological effects of acute exposure to radiofrequency (RF) and microwave radiation are consistent with responses to induced heating, resulting either from frank rises in tissue or body temperature of about 1 0 C or more, or from responses involved in minimising the total heat load. Most responses have been reported at specific energy absorption rates (SARs) above about 1-2 W kg -1 in different animal species exposed under various environmental conditions. These animal, particularly primate, data indicate the sorts of responses that are likely to occur in humans subject to a sufficient heat load. In addition, most animal and cell culture data indicate that RF and microwave exposure is not mutagenic and so will not result in somatic mutation or in hereditary effects; such exposure is therefore unlikely to initiate cancers. With some exceptions that are described below, restrictions on the acute exposure of humans to RF or microwave radiation should be based on the acute responses to raised body temperature. It seems probable that healthy people can tolerate short-term (minute-hour) rises in body temperature of up to about 1 0 C. This rise is well below the maximum tolerable increase but nevertheless represents a significant thermal load. The evidence suggests that the exposure of resting humans in moderate environments at whole-body SARs of 1 W kg -1 , and up to 4 W kg -1 for short periods, will result in body temperature rises of less than 1 0 C. A restriction of whole-body SAR for healthy people to 0

  18. Effects of Ionizing Radiation on Biological Molecules—Mechanisms of Damage and Emerging Methods of Detection

    Science.gov (United States)

    Reisz, Julie A.; Bansal, Nidhi; Qian, Jiang; Zhao, Weiling

    2014-01-01

    Abstract Significance: The detrimental effects of ionizing radiation (IR) involve a highly orchestrated series of events that are amplified by endogenous signaling and culminating in oxidative damage to DNA, lipids, proteins, and many metabolites. Despite the global impact of IR, the molecular mechanisms underlying tissue damage reveal that many biomolecules are chemoselectively modified by IR. Recent Advances: The development of high-throughput “omics” technologies for mapping DNA and protein modifications have revolutionized the study of IR effects on biological systems. Studies in cells, tissues, and biological fluids are used to identify molecular features or biomarkers of IR exposure and response and the molecular mechanisms that regulate their expression or synthesis. Critical Issues: In this review, chemical mechanisms are described for IR-induced modifications of biomolecules along with methods for their detection. Included with the detection methods are crucial experimental considerations and caveats for their use. Additional factors critical to the cellular response to radiation, including alterations in protein expression, metabolomics, and epigenetic factors, are also discussed. Future Directions: Throughout the review, the synergy of combined “omics” technologies such as genomics and epigenomics, proteomics, and metabolomics is highlighted. These are anticipated to lead to new hypotheses to understand IR effects on biological systems and improve IR-based therapies. Antioxid. Redox Signal. 21: 260–292. PMID:24382094

  19. Statistical Modeling of Radiative Transfer and Transient Characteristics for Multilayer Biological Tissue

    Directory of Open Access Journals (Sweden)

    S. Yu. Makarov

    2014-01-01

    Full Text Available The Monte-Carlo method [1] already long ago proved itself as a powerful and universal tool for mathematical modelling in various areas of science and engineering. Researchers often choose this method when it is difficult to find a solution by other ways (or impossible at all, e.g. because of sophisticated analytical dependences, area of modelling or boundary conditions. Certainly, this necessarily statistical and flexible method requires significant computation time, but a continuously increasing computation capability makes it more and more attractive for a choice in specific situation.One of the promising areas to use the method of statistical modelling is description of light propagation in the turbid (scattering media. A high motivation for development of this approach is widely used lasers in biomedicine [3]. Besides, owing to its flexibility, the Monte-Carlo method is also of importance in theoretical researches, in particular, to estimate a degree of adequacy of the offered approximation methods for solving a radiative transfer equation [4].It is known that key parameters of turbid media are an absorption coefficient (characterizes absorption probability of a photon per unit of path length and a scattering coefficient (characterizes scattering probability of a photon per unit of path length. The ratio of each of the coefficients to their sum (extinction defines a probability of "death" or "survival" of a photon, respectively, in interaction with lenses. Generally, in the scattering medium there is a non-coherent radiation component, which in turbid media such as biological tissues, already at the insignificant depth becomes prevailing over the coherent one (residual of the incident laser beam [5].The author used the Monte-Carlo method to simulate optical radiation propagation in the multilayer biological tissues with their optical characteristics corresponding to the skin and subcutaneous tissues. Such a biological tissue is the absorbing

  20. Oxidative mechanisms of biological activity of low-intensity radiofrequency radiation.

    Science.gov (United States)

    Yakymenko, Igor; Tsybulin, Olexandr; Sidorik, Evgeniy; Henshel, Diane; Kyrylenko, Olga; Kyrylenko, Sergiy

    2016-01-01

    This review aims to cover experimental data on oxidative effects of low-intensity radiofrequency radiation (RFR) in living cells. Analysis of the currently available peer-reviewed scientific literature reveals molecular effects induced by low-intensity RFR in living cells; this includes significant activation of key pathways generating reactive oxygen species (ROS), activation of peroxidation, oxidative damage of DNA and changes in the activity of antioxidant enzymes. It indicates that among 100 currently available peer-reviewed studies dealing with oxidative effects of low-intensity RFR, in general, 93 confirmed that RFR induces oxidative effects in biological systems. A wide pathogenic potential of the induced ROS and their involvement in cell signaling pathways explains a range of biological/health effects of low-intensity RFR, which include both cancer and non-cancer pathologies. In conclusion, our analysis demonstrates that low-intensity RFR is an expressive oxidative agent for living cells with a high pathogenic potential and that the oxidative stress induced by RFR exposure should be recognized as one of the primary mechanisms of the biological activity of this kind of radiation.

  1. Effects of gamma radiations on some aspects of the biology of salmonella

    International Nuclear Information System (INIS)

    Ben Miloud, Najla

    2007-01-01

    This work aimed at the study of the effect of gamma radiation on certain aspects of the biology of Salmonella, few works joined this type and gamma radiations. The lethal effect of ionizing radiations was associated at other bacterial types, to an oxidative stress due to the presence of reactive spices of oxygen and leading to deteriorations of membrane cells, proteins and nucleic acids.Thus, we proceeded to an analysis of the viability of four Salmonella serovars subject to different radiation doses going from 0.5 to 2 KGy. The results showed a viability reduction dose dependent with a differential behavior, statistically significant. In order to detect possible radio induced changes at the restriction site of the enzymes XbaI and BlnI usually used for the typing of Salmonella, we carried out a DNA restriction profile analyse of the four serovars by pulsed filed gel electrophoresis. The results showed that no change appeared on the level of these restriction sites for the used enzymes following an irradiation of 2KGy. The study of the sensitivity of Salmonella to antibiotics after a gamma radiation showed that gamma radiation has increased the sensitivity of Salmonella isolates to porin associated antibiotics. Statistical analyses showed that the effect of different irradiation dose treatment on the antibiotic sensitivity is increasingly significant. The irradiation didn't induce modifications of the sensitivity to other antibiotics, probably because of their nature, of their penetration mode inside the cell or their action way. To tray to explain the differential behavior of different serovars to irradiation. We analyzed by Quantitative real time PCR (RT- PCR), the expression level of the ARNm of the genes KATN (catalase non-hemique), DNAK (protein of thermal shock), RNA polymerase as well as of the 16S rRNA. The results showed either a repression or an induction of certain genes under the effect of an irradiation of 2 KGy. (Author)

  2. Biological effects of ionizing radiations. Radiological accident from Goiania, GO, Brazil; Efeitos biologicos das radiacoes ionizantes. Acidente radiologico de Goiania

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, Emico, E-mail: emico.okuno@if.usp.br [Instituto de Fisica da Universidade de Sao Paulo (IF-USP), SP (Brazil)

    2013-01-15

    This article presents the fundaments of radiation physics, the natural and artificial sources, biological effects, radiation protection. We also examine the sequence of events that resulted in Goiania accident with a source of caesium-137 from abandoned radiotherapy equipment and its terrible consequences. (author)

  3. Biological effects of the ionizing radiation. Press breakfast; Effets biologiques des rayonnements ionisants. Petit dejeuner de presse

    Energy Technology Data Exchange (ETDEWEB)

    Flury-Herard, A. [CEA, Direction des Sciences du Vivant, DSV, 75 - Paris (France); Boiteux, S.; Dutrillaux, B. [CEA/Fontenay-aux-Roses, Direction des Sciences du Vivant, DSV, 92 (France); Toledano, M. [CEA Saclay, Direction des Sciences du Vivant, DSV, 91 - Gif-sur-Yvette (France)

    2000-06-01

    This document brings together the subjects discussed during the Press breakfast of 29 june 2000 on the biological effects of the ionizing radiations, with scientists of the CEA and the CNRS. It presents the research programs and provides inquiries on the NDA operating to introduce the NDA damages by ionizing radiations, the possible repairs and the repair efficiency facing the carcinogenesis. Those researches allow the scientists to define laws on radiation protection. (A.L.B.)

  4. Atmospheric ions and probable indirect biological effect of low-level radiation

    International Nuclear Information System (INIS)

    Spurny, Z.

    1984-01-01

    The problem is discussed of the health consequences of low radiation doses (of less than 0.01 Gy). Owing to natural radioactivity and cosmic radiation, ions are formed in the atmosphere which may thus indirectly mediate the effects of ionizing radiation on the organism. The rate of ion formation is approximately 6.1 ion pairs/cm 3 .s and their number will not exceed 10 3 ions/cm 3 . In an environment where artificial radioactive sources are used, the ion concentration may reach up to 10 5 ions/cm 3 . The effect of ions on man may be divided into several types: 1. effect on mental state (behaviour, fatigue, headaches); 2. effect on the cardiovascular system; 3. effect on the bronchial system;and 4. effect on physiological processes, e.g., secretion by endocrine glands. It is not yet known whether the biological effect of small (fast) ions is a function of their electric charge only or of their kinetic energy as well. The view is discussed that low radiation doses through indirect effects have favourable and beneficial influence on the human organism. (M.D.)

  5. Changes in number and function of the lymphocyte populations as a biological indicator for ionizing radiation

    International Nuclear Information System (INIS)

    Dehos, A.; Hinz, G.; Schwarz, E.R.

    1986-01-01

    Siegal and Siegal reported that the number of immunoglobulin producing cells, especially after higher doses of ionizing radiation on isolated mononuclear cells decreases considerably. However, if non-irradiated B cells are cultivated with irradiated (16 Gy) T cells, a significant increase of immunoglobulin production due to the non-irradiated B cells can be observed. Siegal and Siegal described a similar result when they combined and cultivated non-irradiated with irradiated mononuclear cells. The immunoglobulin producing cells decreased in a lower and increased in a higher dose range. The two results can be explained by the fact that Tg cells which act as suppressor cells are relatively sensitive to radiation while Tm cells which are helper cells in this test are relatively resistant. According to these results, B lymphocytes are the most sensitive of the lymphocyte subpopulations. The aim of the project is to clarify whether the mentioned effects are suitable for 'biological dosimetry'. (orig./MG)

  6. The Martian and extraterrestrial UV radiation environment--1. Biological and closed-loop ecosystem considerations.

    Science.gov (United States)

    Cockell, C S; Andrady, A L

    1999-01-01

    The Martian surface is exposed to both UVC radiation (life support systems that use ambient sunlight, must address this problem. Here we examine the UV radiation environment of Mars with respect to biological systems. Action spectra and UV surface fluxes are used to estimate the UV stress that both DNA and chloroplasts would experience. From this vantage point it is possible to consider appropriate measures to address the problem of the Martian UV environment for future long term human exploration and settlement strategies. Some prospects for improving the UV tolerance of organisms are also discussed. Existing artificial ecosystems such as Biosphere 2 can provide some insights into design strategies pertinent to high UV environments. Some prospects for improving the UV tolerance of organisms are also discussed. The data also have implications for the establishment of closed-loop ecosystems using natural sunlight on the lunar surface and elsewhere in the Solar System.

  7. Characterization of Radiation Fields in Biological Shields of Nuclear Power Plants for Assessing Concrete Degradation*

    Directory of Open Access Journals (Sweden)

    Remec Igor

    2016-01-01

    Full Text Available Life extensions of nuclear power plants to 60 and potentially 80 years of operation have renewed interest in long-term material degradation. One material being considered is concrete, with a particular focus on radiation-induced effects. Based on the projected neutron fluence values (E > 0.1 MeV in the concrete biological shields of the US pressurized water reactor fleet and the available data on radiation effects on concrete, some decrease in mechanical properties of concrete cannot be ruled out during extended operation beyond 60 years. An expansion of the irradiated concrete database and a reliable determination of relevant neutron fluence energy cutoff value are necessary to ensure reliable risk assessment for extended operation of nuclear power plants.

  8. Characterization of Radiation Fields in Biological Shields of Nuclear Power Plants for Assessing Concrete Degradationa

    Energy Technology Data Exchange (ETDEWEB)

    Remec, Igor [ORNL; Rosseel, Thomas M [ORNL; Field, Kevin G [ORNL; Le Pape, Yann [ORNL

    2016-01-01

    Life extensions of nuclear power plants to 60 and potentially 80 years of operation have renewed interest in long-term material degradation. One material being considered is concrete, with a particular focus on radiation-induced effects. Based on the projected neutron fluence values (E > 0.1 MeV) in the concrete biological shields of the US pressurized water reactor fleet and the available data on radiation effects on concrete, some decrease in mechanical properties of concrete cannot be ruled out during extended operation beyond 60 years. An expansion of the irradiated concrete database and a reliable determination of relevant neutron fluence energy cutoff value are necessary to ensure reliable risk assessment for extended operation of nuclear power plants.

  9. Low doses of ionizing radiation: Biological effects and regulatory control. Invited papers and discussions. Proceedings of an international conference

    International Nuclear Information System (INIS)

    1998-01-01

    The levels and biological effects resulting from exposure to ionizing radiation are continuously reviewed by the United Nations Committee on the Effects of Atomic Radiation (UNSCEAR). Since its creation in 1928, the International Commission on Radiological Protection (ICRP) has issued recommendations on protection against ionizing radiation. The UNSCEAR estimates and the ICRP recommendations have served as the basis for national and international safety standards on radiation safety, including those developed by the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO). Concerning health effects of low doses of ionizing radiation, the international standards are based on the plausible assumption that, above the unavoidable background radiation dose, the probability of effects increases linearly with dose, i.e. on a 'linear, no threshold' (LNT) assumption. However, in recent years the biological estimates of health effects of low doses of ionizing radiation and the regulatory approach to the control of low level radiation exposure have been much debated. To foster information exchange on the relevant issues, an International Conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, jointly sponsored by the IAEA and WHO in co-operation with UNSCEAR, was held from 17-21 November 1997 at Seville, Spain. These Proceedings contain the invited special reports, keynote papers, summaries of discussions, session summaries and addresses presented at the opening and closing of the Conference

  10. Evaluation of experimental animal biological state at exposure to low-dose ionizing radiation

    International Nuclear Information System (INIS)

    Rozanov, V.A.; Rejtarova, T.Je.; Chernyikov, G.B.; Timoshevs'ka, Je.V.; Kozozojeva, O.O.

    1997-01-01

    New approaches to quantitative evaluation of ionizing radiation absorbed dose within the low-dose range (up to 400 mGy) according to the degree of the organism biological response was developed. The purpose of the stage of the work published in Communication 1 is to evaluate the shifts in the animal behaviour and cellular composition of the blood at irradiation by the dose of 100,200 and 400 mGy. Distinct dose dependence of behaviour reactions and hematological indices within the dose range of 100-400 mGy was not noted

  11. Biological assessment of radiation damage of ATP by soft X-rays

    International Nuclear Information System (INIS)

    Akimitsu, Nobuyoshi; Fujii, Shin-ichiro; Fujii, Kentaro; Tsukimoto, Mitsutoshi; Kojima, Shuji

    2011-01-01

    ATP (Adenosine tri-phosphate), one of ribonucleic acids, acts as an intracellular energy transfer. ATP is used as a substrate to synthesized messenger RNA and as a ligand of inter-cellular signaling. SPring-8 beam line BL23SU can produce high resolution monochromatic soft X-rays. In this study, we analyzed the soft X-ray induced radiation damage of ATP by various biological assessments, such as energy donor activity, genetic information transfer activity and inter-cellular signaling activity. (author)

  12. Study on the Chinese traditional drugs' sterilization and disinfestation by radiation and their biological effects

    International Nuclear Information System (INIS)

    Ma Shouxiang; Yang Ruikun; Liu Desheng

    1987-01-01

    The study of the sterilization and disinfestation by 60 Co γ-radiation and their biological effects on tuber of elevated gastrodia, Chinese angelica and Dangshen have been carried out. The experimental results show that optimal dose was 2 x 10 5 - 4 x 10 5 rad to kill insect in the three Chinese traditional drugs. The results also show that the content of the chemical composition of irradiated group is similar to control group under 6 x 10 5 rad. The thin-layer chromatography colour-maculae are almost the same. They have the same Rf exponent

  13. [Experience of the development special medical technical laboratory for studies of effects caused by potent electromagnetic radiation in biologic objects].

    Science.gov (United States)

    Gorodetsky, B N; Kalyada, T V; Petrov, S V

    2015-01-01

    This article covers topics of creating special medical technical laboratory for medial and biologic studies concerning influence of potent high-frequency elecromagnetic radiation on various biologic objects. The authors gave example of such laboratory, described its construction features, purpose and main characteristics of the included devices.

  14. Multidisciplinary approach of early breast cancer: The biology applied to radiation oncology

    Directory of Open Access Journals (Sweden)

    Azria David

    2010-01-01

    Full Text Available Abstract Early breast cancer treatment is based on a multimodality approach with the application of clinical and histological prognostic factors to determine locoregional and systemic treatments. The entire scientific community is strongly involved in the management of this disease: radiologists for screening and early diagnosis, gynecologists, surgical oncologists and radiation oncologists for locoregional treatment, pathologists and biologists for personalized characterization, genetic counselors for BRCA mutation history and medical oncologists for systemic therapies. Recently, new biological tools have established various prognostic subsets of breast cancer and developed predictive markers for miscellaneous treatments. The aim of this article is to highlight the contribution of biological tools in the locoregional management of early breast cancer.

  15. In Silico Nanodosimetry: New Insights into Nontargeted Biological Responses to Radiation

    Directory of Open Access Journals (Sweden)

    Zdenka Kuncic

    2012-01-01

    nontargeted responses cannot be understood in the framework of DNA-centric radiobiological models; what is needed are new physically motivated models that address the damage-sensing signalling pathways triggered by the production of reactive free radicals. To this end, we have conducted a series of in silico experiments aimed at elucidating the underlying physical processes responsible for nontargeted biological responses to radiation. Our simulation studies implement new results on very low-energy electromagnetic interactions in liquid water (applicable down to nanoscales and we also consider a realistic simulation of extranuclear microbeam irradiation of a cell. Our results support the idea that organelles with important functional roles, such as mitochondria and lysosomes, as well as membranes, are viable targets for ionizations and excitations, and their chemical composition and density are critical to determining the free radical yield and ensuing biological responses.

  16. The use of the dicentric assay for biological dosimetry for radiation accidents in Bulgaria.

    Science.gov (United States)

    Hadjidekova, Valeria; Hristova, Rositsa; Ainsbury, Elizabeth A; Atanasova, Petya; Popova, Ljubomira; Staynova, Albena

    2010-02-01

    This paper details the construction of a 137Cs gamma calibration curve that has been established for dicentric assay and the testing and validation of the curve through biological dosimetry in three situations of suspected workplace overexposure that arose accidentally or through negligence or lack of appropriate safety measures. The three situations were: (1) suspected 137Cs contamination in a factory air supply; (2) suspected exposure to an industrial 192Ir source; and (3) accidental exposure of construction workers to radiation from a 60Co radiotherapy source in a hospital medical physics department. From a total of 24 potentially-exposed subjects, only one worker was found to have a statistically significant dose (0.16 Gy, 95% confidence intervals 0.02-0.43 Gy). In all other cases, the main function of the biological dosimetry was to reassure the subjects that any dose received was low.

  17. Self-Harm

    Science.gov (United States)

    ... Obsessive-Compulsive Disorder Posttraumatic Stress Disorder Schizoaffective Disorder Schizophrenia Related Conditions Anosognosia Dual Diagnosis Psychosis Self-harm Sleep Disorders Suicide About Us ...

  18. [Medico-biological effects of natural UV-radiation: global consequences of the destruction of the ozone layer].

    Science.gov (United States)

    Strzhizhovskiĭ, A D; D'iakonov, A S; Belousov, V V

    1991-01-01

    The effect of UV-B-radiation of high intensity on terrestrial microorganisms, aqueous ecosystems, and plants is described. The effect of UV-B-radiation on humans and animals is discussed and quantitative evaluation of ozone layer destruction is given. It is indicated that potential changes will grow continuously, producing a significant effect on the biosphere. It is concluded that UV-B-radiation as a stimulating agent should be applied with caution in general biology and medicine and in space biology and medicine.

  19. Characterisation of radiation field for irradiation of biological samples at nuclear reactor-comparison of twin detector and recombination methods.

    Science.gov (United States)

    Golnik, N; Gryziński, M A; Kowalska, M; Meronka, K; Tulik, P

    2014-10-01

    Central Laboratory for Radiological Protection is involved in achieving scientific project on biological dosimetry. The project includes irradiation of blood samples in radiation fields of nuclear reactor. A simple facility for irradiation of biological samples has been prepared at horizontal channel of the nuclear reactor MARIA in NCBJ in Poland. The radiation field, composed mainly of gamma radiation and thermal neutrons, has been characterised in terms of tissue kerma using twin-detector technique and recombination chambers. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Proceedings of the Scientific Meeting on Application of Isotopes and Radiation, Book I, Agricultural, Animal and Biology

    International Nuclear Information System (INIS)

    Suhadi, F.; Sisworo, E.L.; Maha, M.; Ismachin, M.; Hilmy, N.; Sumatra, M.; Mugiono; Wandowo; Soebianto, Y.S

    1998-01-01

    The aim of the 10 t h Meeting of the Isotope and Radiation Application is to disseminate the result of research on application of nuclear techniques on agriculture, animal, biology, chemistry, environment, radiation process and industry. The meeting was held in Jakarta, 18-19 February 1998, and there were 6 invited papers and 52 papers indexed individually. This proceeding is divided by two volumes. Volume I and volume II consists of agriculture, animal, biology and chemistry, environment, radiation process and industry, respectively.(ID)

  1. Application of Advanced Functional Maps to the Radiation Treatment Plan for Biological Clinical Target Volumes

    International Nuclear Information System (INIS)

    Park, Ji Yeon; Jung, Won Gyun; Suh, Tae Suk; Lee, Jeong Woo; Ahn, Kook Jin

    2010-01-01

    Anatomical images including computerized tomography (CT) and T1-weighted magnetic resonance (T1-MR) images have been generally used to determine target volumes in radiation treatment plan (RTP). As only conventional images were referenced, tumors have tendency not to be enhanced by administrating agents depending on the tumor grade and patients. Recent advanced MR images, however, could guide physiologically and pathologically significant tumor characteristics. Furthermore, if the multi-functional images are employed, errors from using only one type of image will be complemented and distinct biological parameters can be applied as histological activity index. In this study, biological clinical target volumes (bCTVs) considered vascularity and cellularity can be determined based on multifunctional parametric maps using the in-house software for image registration and analysis. Using the developed software, rCBV and ADC maps were analyzed and bCTVs can be resolved considering vascularity and cellularity. In result, the bCTVs are exported on conventional images for biological RTP using image registration. Based on the multi-functional parametric maps of overlapped tumor regions, malignant sub-volumes can be determined. Multi-functional parametric maps would contribute to the detection of physiological and pathological tumor characteristics which are not be found in conventional images. They would reflect individual tumor biological characteristics to RTP for local tumor control.

  2. Free radicals in biology: oxidative stress and the effects of ionizing radiation.

    Science.gov (United States)

    Riley, P A

    1994-01-01

    The most important electron acceptor in the biosphere is molecular oxygen which, by virtue of its bi-radical nature, readily accepts unpaired electrons to give rise to a series of partially reduced species collectively known as reduced (or 'reactive') oxygen species (ROS). These include superoxide (O.2-), hydrogen peroxide (H2O2), hydroxyl radical (HO.) and peroxyl (ROO.) and alkoxyl (RO.) radicals which may be involved in the initiation and propagation of free radical chain reactions and which are potentially highly damaging to cells. Mechanisms have evolved to restrict and control such processes, partly by compartmentation, and partly by antioxidant defences such as chain-breaking antioxidant compounds capable forming stable free radicals (e.g. ascorbate, alpha-tocopherol) and the evolution of enzyme systems (e.g. superoxide dismutase, catalase, peroxidases) that diminish the intracellular concentration of the ROS. Although some ROS perform useful functions, the production of ROS exceeding the ability of the organism to mount an antioxidant defence results in oxidative stress and the ensuing tissue damage may be involved in certain disease processes. Evidence that ROS are involved in primary pathological mechanisms is a feature mainly of extraneous physical or chemical perturbations of which radiation is perhaps the major contributor. One of the important radiation-induced free-radical species is the hydroxyl radical which indiscriminately attacks neighbouring molecules often at near diffusion-controlled rates. Hydroxyl radicals are generated by ionizing radiation either directly by oxidation of water, or indirectly by the formation of secondary partially ROS. These may be subsequently converted to hydroxyl radicals by further reduction ('activation') by metabolic processes in the cell. Secondary radiation injury is therefore influenced by the cellular antioxidant status and the amount and availability of activating mechanisms. The biological response to

  3. Heavy ion radiation biology research facility and ongoing activities at the Inter-University Accelerator Centre, New Delhi

    International Nuclear Information System (INIS)

    Sarma, Asitikantha

    2014-01-01

    Heavy Ion Radiation Biology is an interdisciplinary science involving use of charged particle accelerator in the study of molecular biology. It is the study of the interaction of a beam of swift heavy ions with a biological system. In contrast to the sparsely ionizing photon or electron radiation, the high velocity charged heavy ions leave a track of densely populated ionization sites resulting in clustered DNA damage. The growing interest in this field encompasses the studies in gene expression, mechanisms of cell death, DNA damage and repair, signal transduction etc. induced because of this unique assault on the genetic material. IUAC radiation biology programme is focused on the in-vitro studies of different effects of heavy ion irradiation on eukaryotic cells. The facility provides a laboratory for pre and post irradiation treatment of samples. The irradiation system called ASPIRE (Automatic Sample Positioning for Irradiation in Radiation Biology Experiments) is installed at the dedicated Radiation Biology Beam line. It produces a nearly uniform flux distribution over a irradiation field of 40 mm diameter. The particle doses can be preselected and repeated within inherent statistical accuracy. The particle energy can also be measured. The facility is at present utilized by the University researchers of India. A few results obtained by the investigators would be presented. The outcome of the research in heavy ion radiation biology would be of immense use in augmenting the efficacy of Hadron therapy of cancer. The results would also contribute to the field of space radiation protection. It would also help in understanding the phenomena subsequent to complex DNA damage. (author)

  4. Ordinance on protection from the harmful effects of X-radiation (X-ray Ordinance). As of January 8, 1987. 3. ed.

    International Nuclear Information System (INIS)

    Hinrichs, O.

    1992-01-01

    The German X-ray Ordinance (Roentgenverordnung) contains the main protective provisions applying to the field of X-ray equipment and sources of unwanted X radiation. It thus forms a complement to the German Radiation Protection Ordinance (Strahlenschutzverordnung). The X-ray Ordinance is based, as is the Radiation Protection Ordinance, on the German Nuclear Energy Act (Atomgesetz). It transposes the same Euratom Directives into national law, through which above all the limit values are defined. The current state of the X-ray Ordinance is that of the text promulgated on 8.01.1987 with the subsequent amendments, the last of which was adopted on 19.12.1990. The brochure also reproduces the Official Memorandum to the X-ray Ordinance, as this gives important indications for the legal construction of the Ordinance. (orig./HSCH) [de

  5. Enhancement of transmission of laser and other radiation by soft turbid physical and biological media

    Science.gov (United States)

    Askar'yan, G. A.

    1982-07-01

    An analysis is made and experimental results are reported of studies of the transmission of laser and other radiation by turbid physical and biological media, such as layers of a scattering medium or human tissue of thickness much greater than the characteristic attenuation length. It is reported that the transmission increases strongly as a result of depression and piercing of soft scattering media. A local pressure applied to a biological tissue produces a transmission enhancement considerably greater than compression of a layer of a physically turbid medium: this is due to the displacement of blood and of muscle out of the compressed region. A reduction in the scattering and absorption is expected to occur also in the case of rf and ionizing radiations, such as charged particles, x rays, gamma rays, etc. It is pointed out that this could be useful in deep irradiation carried out with the aim of inhibiting internal morbid processes (for example, in the spinal cord) and in treatment of neuroinfectious diseases (amyotrophic lateral sclerosis, multiple sclerosis, poliomyelitis, etc.), as well as in oncological conditions, ulcers, etc.

  6. Applications of 'Ultraweak Photon-Emission' from organism in biological radiation-dosimetry

    International Nuclear Information System (INIS)

    Rattemeyer, M.

    1984-05-01

    An important question in radiation-dosimetry is the real effect of ionizing radiation on biological systems. This effect is determined here by measurements of the 'Ultraweak Photon-Emission' (PE) from organism after irradiation with gamma-sources. As biological test objects plant seedlings are used, in this case cucumber seeds (cucumis sativus) after 3-4 d germination in darkness. The PE is measured by a photon-counting- system. The irradiations are carried out either in a TLD-calebrated arrangement with 60 Co/ 137 Cs-sources at low dose-rate (409 μGy.s -1 ) in the range 0-45 Gy, or with a 60 Co-source in a therapeutic apparatus at high dose-rate (95mGy.s -1 ) in the range 50-300 Gy. After irradiation PE-measurements show an increased PE from the seeds; an ozone-effect is tested and can be excluded. In the high dose-range this increase occurs in the spectral range 550-650 nm, and a linear correlation to the applied dose can be ascertained. In the low dose-range there is only found a Biostimulation, but with additional treatment (ethidium-bromide) also a PE-increase occurs, linear correlated to the dose (presumable call membrane damages become visible). By the aid of PE a 'cucumber dosimeter' is calebrated. (Author)

  7. Space experiment "Cellular Responses to Radiation in Space (CELLRAD)": Hardware and biological system tests

    Science.gov (United States)

    Hellweg, Christine E.; Dilruba, Shahana; Adrian, Astrid; Feles, Sebastian; Schmitz, Claudia; Berger, Thomas; Przybyla, Bartos; Briganti, Luca; Franz, Markus; Segerer, Jürgen; Spitta, Luis F.; Henschenmacher, Bernd; Konda, Bikash; Diegeler, Sebastian; Baumstark-Khan, Christa; Panitz, Corinna; Reitz, Günther

    2015-11-01

    One factor contributing to the high uncertainty in radiation risk assessment for long-term space missions is the insufficient knowledge about possible interactions of radiation with other spaceflight environmental factors. Such factors, e.g. microgravity, have to be considered as possibly additive or even synergistic factors in cancerogenesis. Regarding the effects of microgravity on signal transduction, it cannot be excluded that microgravity alters the cellular response to cosmic radiation, which comprises a complex network of signaling pathways. The purpose of the experiment ;Cellular Responses to Radiation in Space; (CELLRAD, formerly CERASP) is to study the effects of combined exposure to microgravity, radiation and general space flight conditions on mammalian cells, in particular Human Embryonic Kidney (HEK) cells that are stably transfected with different plasmids allowing monitoring of proliferation and the Nuclear Factor κB (NF-κB) pathway by means of fluorescent proteins. The cells will be seeded on ground in multiwell plate units (MPUs), transported to the ISS, and irradiated by an artificial radiation source after an adaptation period at 0 × g and 1 × g. After different incubation periods, the cells will be fixed by pumping a formaldehyde solution into the MPUs. Ground control samples will be treated in the same way. For implementation of CELLRAD in the Biolab on the International Space Station (ISS), tests of the hardware and the biological systems were performed. The sequence of different steps in MPU fabrication (cutting, drilling, cleaning, growth surface coating, and sterilization) was optimized in order to reach full biocompatibility. Different coatings of the foil used as growth surface revealed that coating with 0.1 mg/ml poly-D-lysine supports cell attachment better than collagen type I. The tests of prototype hardware (Science Model) proved its full functionality for automated medium change, irradiation and fixation of cells. Exposure of

  8. Biological response to radiation. Studies of model organism, C. elegans, with micro-ion beam

    International Nuclear Information System (INIS)

    Higashitani, Atsushi

    2006-01-01

    Described are mainly author's studies on radiation response and its biological significance in a nematode, C. elegans, particularly focusing its germ cells. The model organism is bisexual and the mature one is suitable to observe the development, differentiation and concomitant chromosome dynamics of male and female germ cells, and accordingly, the responses occurring in those cells at different stages post irradiation of the whole worm. Authors have shown in the organism irradiated by 100 Gy X-ray that pachytene cells in meiosis have high radio-resistance due to their increased expression of enzymes related with homologous recombination. They have also presented the apoptotic cascade in germ cells triggered by radiation by comparison of wild type and ab1-1-gene-deleted worms. Micro-beam of 12 C 5+ ion in Takasaki Ion Accelerators for Advanced Radiation Application (TIARA) has been used to irradiate the body parts of the worm to study the bystander effects, which has revealed that germ cells are shielded from the effect in the worm. It is thought important to use the micro-beam, with which the irradiation area can be precisely controllable, for studying the bystander effect in a body of higher animals like a mouse as well as in worm somatic cells. (T.I.)

  9. Conventional radiation-biological dosimetry using frequencies of unstable chromosome aberrations

    International Nuclear Information System (INIS)

    Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S.

    1998-01-01

    Frequency of chromosome aberrations detected by conventional cytogenetics is a very useful parameter in biological radiodosimetry. It can be used for estimating absorbed doses in individuals working with radioactive sources and individuals accidentally exposed to radiation. In the first case subjects wear physical dosimeters as a routine safety habit. The laboratory at the Institute of Radioprotection and Dosimetry (IRD, Brazil) has been using conventional cytogenetic analysis to complement data obtained by physical dosimetry since 1983. Until now, more than one hundred cases were investigated where individual physical dosimeters detected occupational exposure (above the safety limits allowed). In total, only 34% of these cases were confirmed by conventional cytogenetic dosimetry. Also, conventional cytogenetic analysis following the radiation accident of Goiania (Brazil) in 1987 have been used. Peripheral lymphocytes from 129 exposed or potentially exposed individuals were analyzed for the frequencies of unstable chromosomal aberrations (dicentrics, centric rings and acentrics fragments) to estimate absorbed radiation doses. During the emergency period, doses were estimated to help immediate medical treatment using in vitro calibration curves produced before the accident. Later on, doses were assessed once more using new in vitro calibration curves. A drawback of this technique is that unstable aberrations are lost after exposure. To investigate the mean lifespan of lymphocytes containing dicentric and ring aberrations, we have followed 15 victims of the Goiania accident over all these years. Results suggest that the disappearance of unstable aberrations is dose-dependent. This could explain the variation in the results found among studies in this field

  10. Mechanism of action for anti-radiation vaccine in reducing the biological impact of high-dose gamma irradiation

    Science.gov (United States)

    Maliev, Vladislav; Popov, Dmitri; Jones, Jeffrey A.; Casey, Rachael C.

    Ionizing radiation is a major health risk of long-term space travel, the biological consequences of which include genetic and oxidative damage. In this study, we propose an original mechanism by which high doses of ionizing radiation induce acute toxicity. We identified biological components that appear in the lymphatic vessels shortly after high-dose gamma irradiation. These radiation-induced toxins, which we have named specific radiation determinants (SRD), were generated in the irradiated tissues and then circulated throughout the body via the lymph circulation and bloodstream. Depending on the type of SRD elicited, different syndromes of acute radiation sickness (ARS) were expressed. The SRDs were developed into a vaccine used to confer active immunity against acute radiation toxicity in immunologically naïve animals. Animals that were pretreated with SRDs exhibited resistance to lethal doses of gamma radiation, as measured by increased survival times and survival rates. In comparison, untreated animals that were exposed to similar large doses of gamma radiation developed acute radiation sickness and died within days. This phenomenon was observed in a number of mammalian species. Initial analysis of the biochemical characteristics indicated that the SRDs were large molecular weight (200-250 kDa) molecules that were comprised of a mixture of protein, lipid, carbohydrate, and mineral. Further analysis is required to further identify the SRD molecules and the biological mechanism by which they mediate the toxicity associated with acute radiation sickness. By doing so, we may develop an effective specific immunoprophylaxis as a countermeasure against the acute effects of ionizing radiation.

  11. Mechanism of Action for Anti-Radiation Vaccine in Reducing the Biological Impact of High-Dose Irradiation

    Science.gov (United States)

    Maliev, Vladislav; Popov, Dmitri; Jones, Jeffrey A.; Casey, Rachael C.

    2006-01-01

    Ionizing radiation is a major health risk of long-term space travel, the biological consequences of which include genetic and oxidative damage. In this study, we propose an original mechanism by which high doses of ionizing radiation induce acute toxicity. We identified biological components that appear in the lymphatic vessels shortly after gamma irradiation. These radiation-induced toxins, which we have named specific radiation determinants (SRD), were generated in the irradiated tissues and then collected and circulated throughout the body via the lymph circulation and bloodstream. Depending on the type of SRD elicited, different syndromes of acute radiation sickness (ARS) were expressed. The SRDs were developed into a vaccine used to confer active immunity against acute radiation toxicity in immunologically naive animals. Animals that were pretreated with SRDs exhibited resistance to lethal doses of gamma radiation, as measured by increased survival times and survival rates. In comparison, untreated animals that were exposed to similar large doses of gamma radiation developed acute radiation sickness and died within days. This phenomenon was observed in a number of mammalian species. We partially analyzed the biochemical characteristics of the SRDs. The SRDs were large molecular weight (200-250 kDa) molecules that were comprised of a mixture of protein, lipid, carbohydrate, and mineral. Further analysis is required to further identify the SRD molecules and the biological mechanism by which the mediate the toxicity associated with acute radiation sickness. By doing so, we may develop an effective specific immunoprophylaxis as a countermeasure against the acute effects of ionizing radiation.

  12. Mechanism of Action for Anti-radiation Vaccine in Reducing the Biological Impact of High-dose Gamma Irradiation

    Science.gov (United States)

    Maliev, Vladislav; Popov, Dmitri; Jones, Jeffrey A.; Casey, Rachael C.

    2007-01-01

    Ionizing radiation is a major health risk of long-term space travel, the biological consequences of which include genetic and oxidative damage. In this study, we propose an original mechanism by which high doses of ionizing radiation induce acute toxicity. We identified biological components that appear in the lymphatic vessels shortly after gamma irradiation. These radiation-induced toxins, which we have named specific radiation determinants (SRD), were generated in the irradiated tissues and then collected and circulated throughout the body via the lymph circulation and bloodstream. Depending on the type of SRD elicited, different syndromes of acute radiation sickness (ARS) were expressed. The SRDs were developed into a vaccine used to confer active immunity against acute radiation toxicity in immunologically naive animals. Animals that were pretreated with SRDs exhibited resistance to lethal doses of gamma radiation, as measured by increased survival times and survival rates. In comparison, untreated animals that were exposed to similar large doses of gamma radiation developed acute radiation sickness and died within days. This phenomenon was observed in a number of mammalian species. Initial analysis of the biochemical characteristics indicated that the SRDs were large molecular weight (200-250 kDa) molecules that were comprised of a mixture of protein, lipid, carbohydrate, and mineral. Further analysis is required to further identify the SRD molecules and the biological mechanism by which the mediate the toxicity associated with acute radiation sickness. By doing so, we may develop an effective specific immunoprophylaxis as a countermeasure against the acute effects of ionizing radiation.

  13. Novel Biological Approaches for Testing the Contributions of Single DSBs and DSB Clusters to the Biological Effects of High LET Radiation.

    Science.gov (United States)

    Mladenova, Veronika; Mladenov, Emil; Iliakis, George

    2016-01-01

    The adverse biological effects of ionizing radiation (IR) are commonly attributed to the generation of DNA double-strand breaks (DSBs). IR-induced DSBs are generated by clusters of ionizations, bear damaged terminal nucleotides, and frequently comprise base damages and single-strand breaks in the vicinity generating a unique DNA damage-clustering effect that increases DSB "complexity." The number of ionizations in clusters of different radiation modalities increases with increasing linear energy transfer (LET), and is thought to determine the long-known LET-dependence of the relative biological effectiveness (RBE). Multiple ionizations may also lead to the formation of DSB clusters, comprising two or more DSBs that destabilize chromatin further and compromise overall processing. DSB complexity and DSB-cluster formation are increasingly considered in the development of mathematical models of radiation action, which are then "tested" by fitting available experimental data. Despite a plethora of such mathematical models the ultimate goal, i.e., the "a priori" prediction of the radiation effect, has not yet been achieved. The difficulty partly arises from unsurmountable difficulties in testing the fundamental assumptions of such mathematical models in defined biological model systems capable of providing conclusive answers. Recently, revolutionary advances in methods allowing the generation of enzymatic DSBs at random or in well-defined locations in the genome, generate unique testing opportunities for several key assumptions frequently fed into mathematical modeling - including the role of DSB clusters in the overall effect. Here, we review the problematic of DSB-cluster formation in radiation action and present novel biological technologies that promise to revolutionize the way we address the biological consequences of such lesions. We describe new ways of exploiting the I-SceI endonuclease to generate DSB-clusters at random locations in the genome and describe the

  14. Spinal cordd biological safety comparison of intensity modulated radiotherapy and conventional radiation therapy

    International Nuclear Information System (INIS)

    Xilinbaoleri; Xu Wanlong; Chen Gang; Liu Hao; Wang Ruozheng; Bai Jingping

    2010-01-01

    Objective: To compare the spine intensity modulated radiation therapy (IMRT) and the conventional radiation therapy on the beagle spinal cord neurons, in order to prove the biological safety of IMRT of the spinal cord. Methods: Twelve selected purebred beagles were randomly divided into 2 groups. A beagle clinical model of tumor was mimiced in the ninth and tenth thoracic vertebrae. Then the beagles were irradiated by 2 different models of intensity modulated radiotherapy and conventional radiation therapy, with the total irradiation doses of 50 and 70 Gy. The samples of spinal cord were taken out from the same position of the nine and tenth thoracic vertebrae at the third month after radiation.All the samples were observed by the electron microscope, and the Fas and HSP70 expression in spinal cord neurons were evaluated by immunohistochemistry method. Terminal deoxynucleatidyl transferase mediated dUTP nick and labeling (TUNEL) technique was used to examine the apoptotic cells in the spinal cord. Results: The neurons in the spinal cord of IMRT group were mainly reversible injury, and those in the conventional radiation therapy were mainly apoptosis. Compared with the conventional radiation therapy group [50 Gy group, (7.3 ± 1.1)%; 70 Gy group, (11.3 ± 1.4)%], the apoptosis rate of the spinal cord neurons of the intensity modulated radiotherapy group [50 Gy group, (1.2 ± 0.7)%; 70 Gy group (2.5 ± 0.8)%] was much lower[(50 Gy group, t=0.022, P<0.05; 70 Gy group, t=0.017, P<0.05)]. The expression levels of Fas in the IMPT group (50 Gy group, 4.6 ± 0.8; 70 Gy group, 7.4 ± 1.1) were also much lowerthan those in the other group (50 Gy group, 15.1 ± 6.4; 70 Gy group, 19.3 ± 7.6. 50 Gy group, t=0.231, P<0.05; 70 Gy group, t=0.457, P<0.05), while the expression levels of HSP70 in the IMPT group (50 Gy group, 9.1 ± 0.8; 70 Gy group, 7.3 ± 1.4)were much higher than those in the conventional radiation therapy group (50 Gy group, 2.1 ± 0.9; 70 Gy group, 1.7 ± 0

  15. Physical and biological data collected along the Texas, Mississippi, and Florida Gulf coasts in the Gulf of Mexico as part of the Harmful Algal BloomS Observing System from 19 Aug 1953 to 11 July 2014 (NODC Accession 0120767)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — HABSOS (Harmful Algal BloomS Observing System) is a data collection and distribution system for harmful algal bloom (HAB) information in the Gulf of Mexico. The goal...

  16. Proceedings of the colloquium on the biological and health effects of non-ionizing radiations

    International Nuclear Information System (INIS)

    Point, Sebastien; Boulenguez, Pierre; Martinsons, Christophe; Carre, Samuel; Torriglia, Alicia; Jaadane, Imene; Behar-Cohenz, Francine; Savoldelliz, Michele; Jonetz, Laurent; Chahory, Sabine; Dore, Jean-Francois; Clavel, Jacqueline; Boniol, Mathieu; Greinert, Ruediger; Gandini, Sara; Cesarini, Jean-Pierre; Dieudonne, Mael; Lagroye, Isabelle; Poulletier de Gannes, Florence; Veyret, Bernard; Macrez, Nathalie; Ruffie, Gilles; Haro, Emmanuelle; Hurtier, Annabelle; Taxile, Murielle; Masuda, Hiroshi; Bontempi, Bruno; Nicole, Olivier; Seze, Rene de; Cagnon, Patrice; Thuroczy, Georges; Mauger, Samuel; Mazet, Paul; Agnani, Jean-Benoit; Gaudaire, Francois; Caudeville, Julien; Selmaoui, Brahim; Percherancier, Yann; Veyret, B.; Kohler, Sophie; Leveque, P.; Legros, Alexandre; Modolo, Julien; Thomas, Alex W.; Goulet, Daniel; Plante, Michel; Ostiguy, Genevieve; Souques, Martine; Lambrozo, Jacques; Deschamps, Francois; Magne, Isabelle; Remy, Emmanuel; Souques, Martine; Duburcq, Anne; Bureau, Isabelle; Gercek, Cihan; Kourtiche, Djilali; Scmitt, Pierre; Roth, Patrice; Nadi, Mustapha; Korpinen, Leena

    2014-10-01

    This colloquium was organized by the 'non-ionizing radiations section' of the French Society of Radiation Protection (SFRP). Its goal is to review the works carried out in France regarding the electromagnetic fields risk, the wave-matter interactions and the medical applications. This conference day is the occasion for the scientific actors of the domain to exchange and encourage the pluri-disciplinary collaborations on the biological, clinical, epidemiological, dosimetric and regulatory aspects of the exposure to non-ionizing radiations. This document brings together the available presentations (slides) together with their corresponding abstracts (in French) and dealing with: 1 - Retinal risk in blue light: standard requirements for LED lighting systems (S. Point); 2 - RETINALED: in-vivo study of blue light-related risk - towards a better understanding of retinal pathologies and a better risk assessment (P. Boulenguez); 3 - Can solar UV radiations have a beneficial effect for some cancers? The HeLME-UV project: domestic exposure to solar UV light and malignant lymphoid homeopathies of the child (J.F. Dore); 4 - A major public health problem: UV tanning devices should be prohibited (J.F. Dore); 5 - Is electro-hypersensitivity the result of a nocebo effect? (M. Dieudonne); 6 - Effects of repeated Wi-Fi signal exposure on glial and micro-glial activation in the mouse (I. Lagroye); 7 - RF residential exposure measurements in the French program of the Operative Committee (R. De Seze); 8 - Real-time study of RF fields global cellular effects (Y. Percherencier); 9 - Electromagnetic fields and neuro-degenerative diseases (I. Lagroye); 10 - Example of direct biophysical effect in the domain of ultra-low frequencies: the perception of magnetic phosphenes (A. Legros); 11 - French population exposure to the 50 Hz magnetic field: update of the Expers study (I. Magne); 12 - Cardiac implants immunity with respect to 50/60 Hz electric fields (C. Gercek); 13 - Cardiac implants and

  17. Action spectra affect variability of the climatology of biologically effective ultraviolet radiation on cloud-free days

    International Nuclear Information System (INIS)

    Grifoni, D.; Zipoli, G.; Sabatini, F.; Messeri, G.; Bacci, L.

    2013-01-01

    Action spectrum (AS) describes the relative effectiveness of ultraviolet (UV) radiation in producing biological effects and allows spectral UV irradiance to be weighted in order to compute biologically effective UV radiation (UVBE). The aim of this research was to study the seasonal and latitudinal distribution over Europe of daily UVBE doses responsible for various biological effects on humans and plants. Clear sky UV radiation spectra were computed at 30-min time intervals for the first day of each month of the year for Rome, Potsdam and Trondheim using a radiative transfer model fed with climatological data. Spectral data were weighted using AS for erythema, vitamin D synthesis, cataract and photo-keratitis for humans, while the generalised plant damage and the plant damage AS were used for plants. The daily UVBE doses for the above-mentioned biological processes were computed and are analysed in this study. The patterns of variation due to season (for each location) and latitude (for each date) resulted as being specific for each adopted AS. The biological implications of these results are briefly discussed highlighting the importance of a specific UVBE climatology for each biological process. (authors)

  18. Low doses of ionizing radiation: Relationship between biological benefit and damage induction. A synopsis

    International Nuclear Information System (INIS)

    Feinendegen, L.E.

    2005-01-01

    Absorption of ionizing radiation in biological tissue stochastically interacts with constituent atoms and molecules and always generates energy deposition (track) events accompanied by bursts of reactive oxygen species (ROS). These ROS are quite similar to those ROS that arise abundantly and constantly by normal oxidative metabolism. ROS effects from either source need attention when assessing radiation-induced alterations in biological structure and function. Endogenous ROS alone induce about 10 6 DNA oxyadducts per cell per day compared to about 5x10 -3 total DNA damage per average cell per day from background radiation exposure (1 mGy per year). At this background level, the corresponding ratio of probabilities of endogenous versus radiogenic DNA double strand breaks (DSBs) per cell per day is about 103 with some 25-40 % of low-LET caused radiogenic DNA-DSBs being of the multi-damage-site type. Radiogenic DNA damage increases in proportion to absorbed dose over a certain dose range. By evolution, tissues possess physiological mechanisms of protection against an array of potentially toxic agents, externally from the environment and endogenously from metabolism, mainly against the abundantly and constantly produced ROS. Ad hoc protection operates at a level that is genetically determined. Following small to moderate perturbation of cell-tissue homeostasis by a toxic impact, adaptive responses develop with a delay and may last from hours to weeks, even months, and aim at protecting the system against renewed insults. Protective responses encompass defense by scavenging mechanisms, DNA repair, damage removal largely by apoptosis and immune responses, as well as changes in cell proliferation. Acute low-dose irradiation below about 0.2 Gy can not only disturb cell-tissue homeostasis but also initiate adaptived protection that appears with a delay of hours and may last from less than a day to months. The balance between damage production and adaptive protection favors

  19. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  20. Status of human chromosome aberrations as a biological radiation dosimeter in the nuclear industry

    Energy Technology Data Exchange (ETDEWEB)

    Bender, M.A.

    1978-01-01

    It seems that the determination of peripheral lymphocyte chriomosome aberration levels is now firmly established as a means of biological dosimetry of great value in many phases of the nuclear industry. In the case of large external exposure it can provide valuable quantitative estimates, as well as information on dose distribution and radiation quality. In the case of routine occupational exposures the technique is more qualitative, but is of value particularly in resolving uncertainties as to whether suspected overexposures did in fact occur. Where workers accumulate burdens of internal emitters, aberration analysis provides a valuable, though at present quite qualitative indicator. In spite of the expense of cytogenetic analyses, they are of sufficient value to justify much more widespread application, particularly in high risk situations.

  1. Status of human chromosome aberrations as a biological radiation dosimeter in the nuclear industry

    International Nuclear Information System (INIS)

    Bender, M.A.

    1978-01-01

    It seems that the determination of peripheral lymphocyte chriomosome aberration levels is now firmly established as a means of biological dosimetry of great value in many phases of the nuclear industry. In the case of large external exposure it can provide valuable quantitative estimates, as well as information on dose distribution and radiation quality. In the case of routine occupational exposures the technique is more qualitative, but is of value particularly in resolving uncertainties as to whether suspected overexposures did in fact occur. Where workers accumulate burdens of internal emitters, aberration analysis provides a valuable, though at present quite qualitative indicator. In spite of the expense of cytogenetic analyses, they are of sufficient value to justify much more widespread application, particularly in high risk situations

  2. Biological effect produced by ionizing radiations on occupational workers in Carlos Andrade Marin Hospital

    International Nuclear Information System (INIS)

    Arias Pullaguari, Ines Yolanda

    2003-01-01

    The objective of this study was to establish the biological effects on occupational workers. In this study, have made a bibliographic review of the changes on skin of 217 professionals; between 21 and 70 years radiologists, X-ray technicians, radioisotope workers, nurses and others, which were exposed to ionizing radiation, in the departments of Diagnosis and Treatment of the Hospital Carlos Andrade Marin of the Quito city. From this universe 133 workers were excluded of the analysis. From the totality of lesions produced on the skin; the depilation constituted 40.18%, hyper pigmentation 19.34%, hypo pigmentation 9 %, capillary fragility 13.39%, erythema 13.39%, alopecia 5.37%. From the totality of lesions produced in blood: the leukopenia constituted 20.23% between all workers. The percentage method was used for statical calculation. A bibliographic update is done and the most relevant clinical aspects are reviewed. (The author)

  3. effect of gamma radiation and heat stress on some biological aspects of Spodoptera Littoralis (Boisd)

    International Nuclear Information System (INIS)

    Hazaa, M.A.M.

    2002-01-01

    the present study dealt with the effects of exposure of full - grown pupa of the cotton leaf worm, spodoptera littoralis (Boise) to different high temperatures and/or substerilizing doss of gamma radiation on certain biological and histological aspects of the parental (P 1 ) and first filial (F 1 ) generations. it included the effect on adult longevity and malformation, mating, insemination, fecundity and egg hatchability; beside larval survival till adult emergence and sex ratio of produced adults at different mating crosses between treated and untreated or treated other sex.special attention was given to inherited sterility as well as to the mating competitiveness ability of treated males. the histological changes in testes and ovaries of produced adults were included

  4. Biological effects of high level natural background radiation on human population residing in Kerala coast, South West India

    International Nuclear Information System (INIS)

    Seshadri, M.

    2010-01-01

    The populations residing in Kerala coast are exposed to elevated natural background radiation since many generations. Extensive studies conducted by Bio-Medical group, Bhabha Atomic Research Center have generated wealth of data from this area dealing with epidemiology, monitoring the newborns for malformations, Health Audit Survey, Dosimetry and biological studies using cytogenetic and molecular biology techniques. Our studies on congenital malformations and chromosomal anomalies in children born to parents residing in High Level Natural Radiation Areas in Kerala have not shown any significant difference from normal radiation areas. Screening of over 1,25,000 consecutively born children showed an incidence rate which is comparable in both areas. Other factors such as consanguinity, maternal age and gravida status are more significant contributors than radiation dose to the risk for having malformation in child. Radiation prevalent in the HLNRA is in the dose range of above 1.5 to about 50 mGy per year which translates to doses in the range of nGy per hour. This clearly indicate the number of cells exposed to radiations will be one in few thousand or ten thousands. This throws up challenges in our capability to investigate the effects of radiation on cells. It has become imperative to develop and exploit techniques which will detect responses in single cells and would be able screen large number of cells at a time. Developments in cell biology and molecular biology are now giving us these capabilities. Use of flowcytometer and next generation sequencing would enable us to address many of these questions and provide meaningful approaches to understand the effects of such low dose radiation

  5. Results of the studies of radiation ecology and radiation biology at the Institute of Biology of Komi Science Centre, Ural Division of Russian Academy of Sciences. (On the 40th anniversary of the radiation ecology department)

    International Nuclear Information System (INIS)

    Taskaev, A.I.; Kudyasheva, A.G.; Popova, O.N.; Materij, L.D.; Shuktomova, I.I.; Frolova, N.P.; Kozubov, G.M.; Zajnullin, V.G.; Ermakova, O.V.; Rakin, A.O.; Bashlykova, L.A.

    2000-01-01

    Materials on the history of foundation of the radiation Ecology Department at the Institute of Biology of the Komi Science Centre of the Russian Academy of Sciences on the occasion of its 40-th anniversary are presented. The results of studies on radiation effects in low doses on the plant and animal populations as well as on radionuclide migration in natural biogeocenoses by increased radiation levels are analyzed. The performed complex studies were used as the basis for developing methodological approaches to the solution of a number of problems on the surface radioecology. Multiyear studies on the biogeocenoses of increased radioactivity of different origin made it possible to obtain multiple materials, indicating high diversity and specificity of reaction of living organisms in response to the background low level chronic irradiation. Attention was paid to studies on the Komi contamination by atmospheric radioactive fall-outs as well as to studies on the consequences of radioactive contamination of the Ukrainian Polesje due to the Chernobyl accident [ru

  6. Application of TSH bioindicator for studying the biological efficiency of radiation

    International Nuclear Information System (INIS)

    Cebulska-Wasilewska, A.; Rekas, K.; Kim, J.K.

    1999-01-01

    The effectiveness of neutrons from a californium-252 source in the induction of various abnormalities in the Tradescantia clone 4430 stamen hair cells (TSH assay) was studied. Special attention was paid to check whether any enhancement in effects caused by the process of boron neutron capture is visible in the cells enriched with boron ions. Two chemicals (borax and BSH) were applied to introduce boron-10 ions into cells. Inflorescences, normal or prepared with chemicals containing boron, were irradiated in the air with neutrons from the 252 Cf source at KOREI, Taejon, Korea. To estimate the relative biological effectiveness (RBE) of the boron under the study, Tradescantia inflorescences without chemical pretreatment were irradiated with various doses of X-rays. The ranges of radiation doses for neutrons were 0-0.1Gy and for X-rays 0-0.5 Gy. After time needed to complete the postirradiation repair tradescantia cuttings were transported to Cracow were screening of gene and lethal mutations in somatic cells of stamen hairs have been done and dose response relationships were plotted. In two independent experimental studies an alternation of dose-response curves was observed, probably due to slight changes in the postexposure plant treatment. However, it has not results in the change of the maximal RBE values, which for the induction of gene mutations were estimated as 5.6 in the pilot studies and 5.8 one year later. Inflorescences pretreated with borax and BSH responded to neutrons differently. The values of RBE have changed from 5.6 to 7.9 in the case of plants pretreated with 240 ppm of B-10 from borax, and 5.8 to 7.2 in the case of 400 ppm of B-10 from BSH. The results showed an increase, although statistically insignificant, in biological efficiency of radiation from the 252 Cf source in the samples pretreated with boron containing chemicals. (author)

  7. Physical interaction of ionising radiations with the intracellular macromolecular target DNA and its biological consequences

    International Nuclear Information System (INIS)

    Geard, C.R.; Loucas, B.D.

    1995-01-01

    Chromosomal DNA breaks were evaluated in normal human fibroblasts after irradiation of non-cycling G1 phase cells with 90 keV·μm -1 α particles and 250 kV p X rays. Yields were measured using the premature chromosome condensation technique in interphase cells, straight after and 24 h after irradiation, and by mitotic scoring of terminal deletions following cellular release at 24 h and progression through the cell cycle. Yields were related to the frequencies of energy deposition events per cell nucleus estimated microdosimetrically for X rays and by relating fluence to nuclear cross-sectional areas for the α particles. Linear relationships were found for both radiations and at all three times post-irradiation. Initial break yields of 1.3 x 10 o and 1.6 x 10 -2 per energy deposition event for α particles and X rays respectively, changed to residual yields (24 h) of 4.0 x 10 -1 and 1.3 x 10 -3 , and for terminal deletions at mitosis to 6.0 x 10 -3 and 4.0 x 10 -5 per energy deposition event. That is, one 90 keV·μm -1 α particle is about 100 times more biologically effective than an electron track from 250 kV p X rays and greater than 99% of initially induced chromosomal DNA breaks are repaired/misrepaired before the next mitosis. Misrepair will involve illegitimate interactions and combinations of pairs of lesions, entities which pre-dominate at mitosis, while a failure to repair/misrepair resulting in relic DNA double strand breaks is likely to be of minimal consequence. Lesion interaction, proximity dependent, and largely irrespective of LET dependent lesion severity will then be the principal basis for the unwanted biological sequelae from ionising radiations. (Author)

  8. Investigation of the effect of ionizing radiation on gene expression variation by the 'DNA chips': feasibility of a biological dosimeter

    International Nuclear Information System (INIS)

    Gruel, G.

    2005-01-01

    After having described the different biological effects of ionizing radiation and the different approaches to biological dosimetry, and introduced 'DNA chips' or DNA micro-arrays, the author reports the characterization of gene expression variations in the response of cells to a gamma irradiation. Both main aspects of the use DNA chips are investigated: fundamental research and diagnosis. This research thesis thus proposes an analysis of the effect of ionizing radiation using DNA chips, notably by comparing gene expression modifications measured in mouse irradiated lung, heart and kidney. It reports a feasibility study of bio-dosimeter based on expression profiles

  9. Risk of ocular exposure to biologically effective UV radiation in different geographical directions.

    Science.gov (United States)

    Wang, Fang; Hu, Liwen; Gao, Qian; Gao, Yanyan; Liu, Guangcong; Zheng, Yang; Liu, Yang

    2014-01-01

    To quantify ocular exposure to solar ultraviolet radiation (UVR) and to assess the risk of eye damage in different geographical directions due to UVR exposure, we used a spectrometer and a manikin to measure horizontal ambient and ocular exposure UVR in different geographical directions at four different locations at the Northern Hemisphere. Describing the relationship of exposure to risk of eye damage requires the availability of UV hazard weighting function. So, we used the UV hazard weighting function (ICNIRP) proposed by International Commission on Non-Ionizing Radiation Protection to determine the biologically effective UV irradiance (UVBEeye ) and then cumulative effective radiant exposure (Heye ) to shown the risk of eye. We found that in different geographical directions, distributions of ocular exposure to UVR were markedly different from those of horizontal ambient UVR. When the midday maximum SEA > 50°, eye received more UVR from the east and west directions during the morning and evening hours, respectively. However, when the midday maximum SEA eye received more UVR from the south direction at noon. The results of this research indicate that the higher risk of eye caused by UVR varies according to the midday maximum SEA corresponding to different geographical direction. © 2014 The American Society of Photobiology.

  10. Simulated studies on the biological effects of space radiation on quiescent human fibroblasts

    Science.gov (United States)

    Ding, Nan; Pei, Hailong; He, Jinpeng; Furusawa, Yoshiya; Hirayama, Ryoichi; Liu, Cuihua; Matsumoto, Yoshitaka; Li, He; Hu, Wentao; Li, Yinghui; Wang, Jufang; Wang, Tieshan; Zhou, Guangming

    2013-10-01

    High charge and energy (HZE) particles are severe risk to manned long-term outer space exploration. Studies on the biological effects of space HZE particles and the underlying mechanisms are essential to the accurate risk assessment and the development of efficient countermeasure. Since majority of the cells in human body stay quiescent (G0 phase), in this study, we established G0 cell and G1 cell models by releasing human normal embryonic lung fibroblast cells from contact inhibition and studied the radiation toxicity of various kinds of HZE particles. Results showed that all of the particles were dose-dependently lethal and G0 cells were more radioresistant than G1 cells. We also found that 53BP1 foci were induced in a LET- and fluence-dependent manner and fewer foci were induced in G0 cells than G1 cells, however, the decrease of foci in 24 h after irradiation was highly relevant to the type of particles. These results imply that even though health risk of space radiation is probably overestimated by the data obtained with exponentially growing cells, whose radiosensitivity is similar to G1 cells, the risk of space HZE particles is un-ignorable and accurate assessment and mechanistic studies should be deepened. The diverse abilities of G0 cells and G1 cells in repairing DNA damages induced by HZE particles emphasize the importance in studying the impact of HZE particles on DNA damage repair pathways.

  11. THz near-field imaging of biological tissues employing synchrotron radiation

    International Nuclear Information System (INIS)

    Schade, Ulrich; Holldack, Karsten; Martin, Michael C.; Fried, Daniel

    2004-01-01

    Terahertz scanning near-field infrared microscopy (SNIM) below 1 THz is demonstrated. The near-field technique benefits from the broadband and highly brilliant coherent synchrotron radiation (CSR) from an electron storage ring and from a detection method based on locking onto the intrinsic time structure of the synchrotron radiation. The scanning microscope utilizes conical wave guides as near-field probes with apertures smaller than the wavelength. Different cone approaches have been investigated to obtain maximum transmittance. Together with a Martin-Puplett spectrometer the set-up enables spectroscopic mapping of the transmittance of samples well below the diffraction limit. Spatial resolution down to about lambda/40 at 2 wavenumbers (0.06 THz) is derived from the transmittance spectra of the near-field probes. The potential of the technique is exemplified by imaging biological samples. Strongly absorbing living leaves have been imaged in transmittance with a spatial resolution of 130 mu-m at about 12 wave numbers (0.36 THz). The THz near-field images reveal distinct structural differences of leaves from different plants investigated. The technique presented also allows spectral imaging of bulky organic tissues. Human teeth samples of various thicknesses have been imaged between 2 and 20 wavenumbers (between 0.06and 0.6 THz). Regions of enamel and dentin within tooth samples are spatially and spectrally resolved, and buried caries lesions are imaged through both the outer enamel and into the underlying dentin

  12. Biological Effectiveness and Application of Heavy Ions in Radiation Therapy Described by a Physical and Biological Model

    DEFF Research Database (Denmark)

    Olsen, Kjeld J.; Hansen, Johnny W.

    is inadequately described by an RBE-factor, whereas the complete formulation of the probability of survival must be used, as survival depends on both radiation quality and dose. The theoretical model of track structure can be used in dose-effect calculations for neutron-, high-LET, and low-LET radiation applied...... simultaneously in therapy....

  13. Cutting and Self-Harm

    Science.gov (United States)

    ... Your feelings Feeling sad Cutting and self-harm Cutting and self-harm Self-harm, sometimes called self- ... There are many types of self-injury, and cutting is one type that you may have heard ...

  14. Probing droplets with biological colloidal suspensions on smart surfaces by synchrotron radiation micro- and nano-beams

    KAUST Repository

    Marinaro, Giovanni

    2015-03-01

    Droplets with colloidal biological suspensions evaporating on substrates with defined wetting properties generate confined environments for initiating aggregation and self-assembly processes. We describe smart micro- and nanostructured surfaces, optimized for probing single droplets and residues by synchrotron radiation micro- and nanobeam diffraction techniques. Applications are presented for Ac-IVD and β-amyloid (1-42) peptides capable of forming cross-β sheet structures. Complementary synchrotron radiation FTIR microspectroscopy addresses secondary structure formation. The high synchrotron radiation source brilliance enables fast raster-scan experiments. © 2015 Elsevier Ltd.

  15. Biological-based optimization and volumetric modulated arc therapy delivery for stereotactic body radiation therapy

    International Nuclear Information System (INIS)

    Diot, Quentin; Kavanagh, Brian; Timmerman, Robert; Miften, Moyed

    2012-01-01

    Purpose: To describe biological-based optimization and Monte Carlo (MC) dose calculation-based treatment planning for volumetric modulated arc therapy (VMAT) delivery of stereotactic body radiation therapy (SBRT) in lung, liver, and prostate patients. Methods: Optimization strategies and VMAT planning parameters using a biological-based optimization MC planning system were analyzed for 24 SBRT patients. Patients received a median dose of 45 Gy [range, 34-54 Gy] for lung tumors in 1-5 fxs and a median dose of 52 Gy [range, 48-60 Gy] for liver tumors in 3-6 fxs. Prostate patients received a fractional dose of 10 Gy in 5 fxs. Biological-cost functions were used for plan optimization, and its dosimetric quality was evaluated using the conformity index (CI), the conformation number (CN), the ratio of the volume receiving 50% of the prescription dose over the planning target volume (Rx/PTV50). The quality and efficiency of the delivery were assessed according to measured quality assurance (QA) passing rates and delivery times. For each disease site, one patient was replanned using physical cost function and compared to the corresponding biological plan. Results: Median CI, CN, and Rx/PTV50 for all 24 patients were 1.13 (1.02-1.28), 0.79 (0.70-0.88), and 5.3 (3.1-10.8), respectively. The median delivery rate for all patients was 410 MU/min with a maximum possible rate of 480 MU/min (85%). Median QA passing rate was 96.7%, and it did not significantly vary with the tumor site. Conclusions: VMAT delivery of SBRT plans optimized using biological-motivated cost-functions result in highly conformal dose distributions. Plans offer shorter treatment-time benefits and provide efficient dose delivery without compromising the plan conformity for tumors in the prostate, lung, and liver, thereby improving patient comfort and clinical throughput. The short delivery times minimize the risk of patient setup and intrafraction motion errors often associated with long SBRT treatment

  16. Physics fundamentals and biological effects of synchrotron radiation therapy; Fundamentos fisicos y efectos biologicos de la radioterapia con radiacion sincrotron

    Energy Technology Data Exchange (ETDEWEB)

    Prezado, Y.

    2010-07-01

    The main goal of radiation therapy is to deposit a curative dose in the tumor without exceeding the tolerances in the nearby healthy tissues. For some radioresistant tumors, like gliomas, requiring high doses for complete sterilization, the major obstacle for curative treatment with ionizing radiation remains the limited tolerance of the surrounding healthy tissue. This limitation is particularly severe for brain tumors and, especially important in children, due to the high risk of complications in the development of the central nervous system. In addition, the treatment of tumors close to an organ at risk, like the spinal cord, is also restricted. One possible solution is the development of new radiation therapy techniques exploiting radically different irradiation modes and modifying, in this way, the biological equivalent doses. This is the case of synchrotron radiation therapy (SR T). In this work the three new radiation therapy techniques under development at the European Synchrotron Radiation Facility (ESR F), in Grenoble (France) will be described, namely: synchrotron stereotactic radiation therapy (Ssr), microbeam radiation therapy (MR T) and mini beam radiation therapy. The promising results in the treatment of the high grade brain tumors obtained in preclinical studies have paved the way to the clinical trials. The first patients are expected in the fall of 2010. (Author).

  17. Low dose effects of ionizing radiations in in vitro and in vivo biological systems: a multi-scale approach study

    International Nuclear Information System (INIS)

    Antoccia, A.; Berardinelli, F.; Argazzi, E.; Balata, M.; Bedogni, R.

    2011-01-01

    Long-term biological effects of low-dose radiation are little known nowadays and its carcinogenic risk is estimated on the assumption that risk remains linearly proportional to the radiation dose down to low-dose levels. However in the last 20 years this hypothesis has gradually begun to seem in contrast with a huge collection of experimental evidences, which has shown the presence of plethora of non-linear phenomena (including hypersensitivity and induced radioresistance, adaptive response, and non-targeted phenomena like bystander effect and genomic instability) occurring after low-dose irradiation. These phenomena might imply a non-linear behaviour of cancer risk curves in the low-dose region and question the validity of the Linear No-Threshold (LNT) model currently used for cancer risk assessment through extrapolation from existing high-dose data. Moreover only few information is available regarding the effects induced on cryo preserved cells by multi-year background radiation exposure, which might induce a radiation-damage accumulation, due to the inhibition of cellular repair mechanisms. In this framework, the multi-year Excalibur (Exposure effects at low doses of ionizing radiation in biological culture) experiment, funded by INFN-CNS5, has undertaken a multi-scale approach investigation on the biological effects induced in in vitro and in vivo biological systems, in culture and cryo preserved conditions, as a function of radiation quality (X/γ-rays, protons, He-4 ions of various energies) and dose, with particular emphasis on the low-dose region and non-linear phenomena, in terms of different biological endpoints.

  18. Prognostic cell biological markers in cervical cancer patients primarily treated with (chemo)radiation : a systematic review

    NARCIS (Netherlands)

    Noordhuis, Maartje G; Eijsink, Jasper J H; Roossink, Frank; de Graeff, Pauline; Pras, Elisabeth; Schuuring, Ed; Wisman, G Bea A; de Bock, Geertruida H; van der Zee, Ate G J

    2011-01-01

    The aim of this study was to systematically review the prognostic and predictive significance of cell biological markers in cervical cancer patients primarily treated with (chemo)radiation. A PubMed, Embase, and Cochrane literature search was performed. Studies describing a relation between a cell

  19. The impact of biology on risk assessment -- Workshop of the National Research Council's board on radiation effects research. Meeting report

    International Nuclear Information System (INIS)

    Fry, R.J.M.; Grosovsky, A.; Hanawalt, P.C.; Ullrich, R.L.

    1997-01-01

    The linear, nonthreshold extrapolation from a dose-response relationship for ionizing radiation derived at higher doses to doses for which regulatory standards are proposed is being challenged by some scientists and defended by others. It appears that the risks associated with exposures to doses of interest are below the risks that can be measured with epidemiologic studies. Therefore, many have looked to biology to provide information relevant to risk assessment. The workshop reported here, ''The Impact of biology on Risk Assessment,'' was planned to address the need for further information by bringing together scientists who have been working in key fields of biology and others who have been contemplating the issues associated specifically with this question. The goals of the workshop were to summarize and review the status of the relevant biology, to determine how the reported biologic data might influence risk assessment, and to identify subjects on which more data is needed

  20. Amylase and blood cell-count hematological radiation-injury biomarkers in a rhesus monkey radiation model-use of multiparameter and integrated biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Blakely, W.F. [Uniformed Services University, Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)], E-mail: blakely@afrri.usuhs.mil; Ossetrova, N.I.; Manglapus, G.L.; Salter, C.A.; Levine, I.H.; Jackson, W.E.; Grace, M.B.; Prasanna, P.G.S.; Sandgren, D.J.; Ledney, G.D. [Uniformed Services University, Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)

    2007-07-15

    Effective medical management of suspected radiation exposure incidents requires the recording of dynamic medical data (clinical signs and symptoms), biological assessments of radiation exposure, and physical dosimetry in order to provide diagnostic information to the treating physician and dose assessment for personnel radiation protection records. The need to rapidly assess radiation dose in mass-casualty and population-monitoring scenarios prompted an evaluation of suitable biomarkers that can provide early diagnostic information after exposure. We investigated the utility of serum amylase and hematological blood-cell count biomarkers to provide early assessment of severe radiation exposures in a non-human primate model (i.e., rhesus macaques; n=8) exposed to whole-body radiation of {sup 60}Co-gamma rays (6.5 Gy, 40cGymin{sup -1}). Serum amylase activity was significantly elevated (12.3{+-}3.27- and 2.6{+-}0.058-fold of day zero samples) at 1 and 2-days, respectively, after radiation. Lymphocyte cell counts decreased ({<=}15% of day zero samples) 1 and 2 days after radiation exposure. Neutrophil cell counts increased at day one by 1.9({+-}0.38)-fold compared with levels before irradiation. The ratios of neutrophil to lymphocyte cell counts increased by 13({+-}2.66)- and 4.23({+-}0.95)-fold at 1 and 2 days, respectively, after irradiation. These results demonstrate that increases in serum amylase activity along with decreases of lymphocyte counts, increases in neutrophil cell counts, and increases in the ratio of neutrophil to lymphocyte counts 1 day after irradiation can provide enhanced early triage discrimination of individuals with severe radiation exposure and injury. Use of the biodosimetry assessment tool (BAT) application is encouraged to permit dynamic recording of medical data in the management of a suspected radiological casualty.

  1. Nanosilver – Harmful effects of biological activity

    Directory of Open Access Journals (Sweden)

    Anna Maria Świdwińska-Gajewska

    2014-12-01

    Full Text Available Nanosilver, also identified as colloidal silver, has been known and used for ages to combat diseases or prolong food freshness. It usually occurs in the form of a suspension consisting of particles of size < 100 nm. Due to its specific properties, silver nanoparticles are used in many technologies to produce medical devices, textiles, conductive materials or photovoltaic cells. The growing popularity of nanosilver applications increases the number of people occupationally exposed to this substance. Potential exposure routes for silver nanoparticles are through dermal, oral and inhalation pathways. Silver nanoparticles may be absorbed through the lungs, intestine, and through the skin into circulation and thus may reach such organs as the liver, kidney, spleen, brain, heart and testes. Nanosilver may cause mild eyes and skin irritations. It can also act as a mild skin allergen. Inhalation of silver nanoparticles mainly affects the lungs and liver. It has been demonstrated that silver nanoparticles may be genotoxic to mammalian cells. There are some alarming reports on the adverse effects of silver nanoparticles on reproduction of experimental animals. Exposure to silver nanoparticles may exert a neurotoxic effect and affect cognitive functions, causing the impairment of short-term and working memory. Maximum admissible concentration (MAC for the inhalable fraction of silver of 0.05 mg/m3 is currently binding in Poland. In light of toxicological studies of silver nanoparticles it seems reasonable to update the hygiene standards for silver with nanoparticles as a separate fraction. Med Pr 2014;65(6:831–845

  2. Nanosilver – Harmful effects of biological activity

    OpenAIRE

    Anna Maria Świdwińska-Gajewska; Sławomir Czerczak

    2014-01-01

    Nanosilver, also identified as colloidal silver, has been known and used for ages to combat diseases or prolong food freshness. It usually occurs in the form of a suspension consisting of particles of size < 100 nm. Due to its specific properties, silver nanoparticles are used in many technologies to produce medical devices, textiles, conductive materials or photovoltaic cells. The growing popularity of nanosilver applications increases the number of people occupationally exposed to this subs...

  3. Effects of low power microwave radiation on biological activity of Collagenase enzyme and growth rate of S. Cerevisiae yeast

    Science.gov (United States)

    Alsuhaim, Hamad S.; Vojisavljevic, Vuk; Pirogova, E.

    2013-12-01

    Recently, microwave radiation, a type/subset of non-ionizing electromagnetic radiation (EMR) has been widely used in industry, medicine, as well as food technology and mobile communication. Use of mobile phones is rapidly growing. Four years from now, 5.1 billion people will be mobile phone users around the globe - almost 1 billion more mobile users than the 4.3 billion people worldwide using them now. Consequently, exposure to weak radiofrequency/microwave radiation generated by these devices is markedly increasing. Accordingly, public concern about potential hazards on human health is mounting [1]. Thermal effects of radiofrequency/microwave radiation are very well-known and extensively studied. Of particular interest are non-thermal effects of microwave exposures on biological systems. Nonthermal effects are described as changes in cellular metabolism caused by both resonance absorption and induced EMR and are often accompanied by a specific biological response. Non-thermal biological effects are measurable changes in biological systems that may or may not be associated with adverse health effects. In this study we studied non-thermal effects of low power microwave exposures on kinetics of L-lactate dehydrogenase enzyme and growth rate of yeast Saccharomyces Cerevisiae strains type II. The selected model systems were continuously exposed to microwave radiation at the frequency of 968MHz and power of 10dBm using the designed and constructed (custom made) Transverse Electro-Magnetic (TEM) cell [2]. The findings reveal that microwave radiation at 968MHz and power of 10dBm inhibits L-lactate dehydrogenase enzyme activity by 26% and increases significantly (15%) the proliferation rate of yeast cells.

  4. Proceedings of the international conference on emerging frontiers and challenges in radiation biology: abstracts

    International Nuclear Information System (INIS)

    Purohit, R.K.; Chakrawarti, Aruna; Agarwal, Manisha; Arora, Anil

    2012-01-01

    This abstract volume includes abstracts related to six technical sessions of the conference viz., Radiation induced genomic instability and bystander effects, Radiation dosimetry and dose limits, Radiation protection and nuclear technology application, Molecular diagnosis and targeted therapy for cancer, cancer care and chemoradiotherapy, health hazards of radiation and protection. Papers relevant to INIS are indexed separately

  5. Association Between Radiation Necrosis and Tumor Biology After Stereotactic Radiosurgery for Brain Metastasis

    International Nuclear Information System (INIS)

    Miller, Jacob A.; Bennett, Elizabeth E.; Xiao, Roy; Kotecha, Rupesh; Chao, Samuel T.; Vogelbaum, Michael A.; Barnett, Gene H.; Angelov, Lilyana; Murphy, Erin S.; Yu, Jennifer S.; Ahluwalia, Manmeet S.

    2016-01-01

    Background: The primary dose-limiting toxicity of stereotactic radiosurgery (SRS) is radiation necrosis (RN), which occurs after approximately 5% to 10% of treatments. This adverse event may worsen neurologic deficits, increase the frequency and cost of imaging, and necessitate prolonged treatment with steroids or antiangiogenic agents. Previous investigations have primarily identified lesion size and dosimetric constraints as risk factors for RN in small populations. We hypothesized that disease histology, receptor status, and mutational status are associated with RN. Methods and Materials: All patients presenting with brain metastasis between 1997 and 2015 who underwent SRS and subsequent radiographic follow-up at a single tertiary-care institution were eligible for inclusion. The primary outcome was the cumulative incidence of radiographic RN. Multivariate competing risks regression was used to identify biological risk factors for RN. Results: 1939 patients (5747 lesions) were eligible for inclusion; 285 patients (15%) experienced radiographic RN after the treatment of 427 (7%) lesions. After SRS, the median time to RN was 7.6 months. After multivariate analysis, graded prognostic assessment, renal pathology, lesion diameter, and the heterogeneity index remained independently predictive of RN in the pooled cohort. In subset analyses of individual pathologies, HER2-amplified status (hazard ratio [HR] 2.05, P=.02), BRAF V600+ mutational status (HR 0.33, P=.04), lung adenocarcinoma histology (HR 1.89, P=.04), and ALK rearrangement (HR 6.36, P<.01) were also associated with RN. Conclusions: In the present investigation constituting the largest series of RN, several novel risk factors were identified, including renal histology, lung adenocarcinoma histology, HER2 amplification, and ALK/BRAF mutational status. These risk factors may be used to guide clinical trial design incorporating biological risk stratification or dose escalation. Future studies determining the

  6. Association Between Radiation Necrosis and Tumor Biology After Stereotactic Radiosurgery for Brain Metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Jacob A. [Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio (United States); Bennett, Elizabeth E. [Department of Neurological Surgery, Neurological Institute, Cleveland Clinic, Cleveland, Ohio (United States); Xiao, Roy [Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio (United States); Kotecha, Rupesh [Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Chao, Samuel T. [Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio (United States); Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Vogelbaum, Michael A.; Barnett, Gene H.; Angelov, Lilyana [Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio (United States); Department of Neurological Surgery, Neurological Institute, Cleveland Clinic, Cleveland, Ohio (United States); Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Murphy, Erin S.; Yu, Jennifer S. [Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio (United States); Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Ahluwalia, Manmeet S. [Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio (United States); Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); and others

    2016-12-01

    Background: The primary dose-limiting toxicity of stereotactic radiosurgery (SRS) is radiation necrosis (RN), which occurs after approximately 5% to 10% of treatments. This adverse event may worsen neurologic deficits, increase the frequency and cost of imaging, and necessitate prolonged treatment with steroids or antiangiogenic agents. Previous investigations have primarily identified lesion size and dosimetric constraints as risk factors for RN in small populations. We hypothesized that disease histology, receptor status, and mutational status are associated with RN. Methods and Materials: All patients presenting with brain metastasis between 1997 and 2015 who underwent SRS and subsequent radiographic follow-up at a single tertiary-care institution were eligible for inclusion. The primary outcome was the cumulative incidence of radiographic RN. Multivariate competing risks regression was used to identify biological risk factors for RN. Results: 1939 patients (5747 lesions) were eligible for inclusion; 285 patients (15%) experienced radiographic RN after the treatment of 427 (7%) lesions. After SRS, the median time to RN was 7.6 months. After multivariate analysis, graded prognostic assessment, renal pathology, lesion diameter, and the heterogeneity index remained independently predictive of RN in the pooled cohort. In subset analyses of individual pathologies, HER2-amplified status (hazard ratio [HR] 2.05, P=.02), BRAF V600+ mutational status (HR 0.33, P=.04), lung adenocarcinoma histology (HR 1.89, P=.04), and ALK rearrangement (HR 6.36, P<.01) were also associated with RN. Conclusions: In the present investigation constituting the largest series of RN, several novel risk factors were identified, including renal histology, lung adenocarcinoma histology, HER2 amplification, and ALK/BRAF mutational status. These risk factors may be used to guide clinical trial design incorporating biological risk stratification or dose escalation. Future studies determining the

  7. Developing point of care and high-throughput biological assays for determining absorbed radiation dose

    International Nuclear Information System (INIS)

    Joiner, Michael C.; Thomas, Robert A.; Grever, William E.; Smolinski, Joseph M.; Divine, George W.; Konski, Andre A.; Auner, Gregory W.; Tucker, James D.

    2011-01-01

    Background and purpose: Systems are being developed to assess radiation exposure based on leukocyte mRNA levels obtained by finger-stick sampling. The goal is to provide accurate detection of dose exposures up to 10 Gy for up to 1 week following exposure. We previously showed that specific mRNA sequences increase expression within an hour of exposure, and some genes continue to show elevated expression for at least 24 h. Full duration and dose-dependence of this persistence remain to be determined. In the present study, real-time quantitative PCR (qPCR) was used to determine changes in gene expression. qPCR can rapidly analyze small blood samples and could be adopted into a field-portable instrument that provides a radiation dose readout within 30 min. Materials and methods: From previous microarray analysis of 21,000 genes expressed in human lymphoblastoid cells 4 h post-irradiation (0–4 Gy), 118 genes were selected for evaluation by qPCR of gene expression in the leukocytes of human blood irradiated in vitro with doses of 0–10 Gy from a Co-60 gamma source at a dose rate of 30 cGy/min. Results: Blood from 20 normal healthy human donors yielded many mRNA sequences that could be used for radiation dosimetry. We observed four genes with large and persistent responses following exposure: ASTN2, CDKN1A, GADD45A, and GDF15. Five genes were identified as reliably non-responsive and were suitable for use as endogenous controls: DPM1, ITFG1, MAP4, PGK1, and SLC25A36; of these, ITFG1 was used for the analyses presented here. A significant dose-responsive increase in expression occurred for CDKN1A that was >16-fold at 10 Gy and 3-fold at 0.5 Gy compared to pre-irradiation values. Conclusions: These data show large, selective increases in mRNA transcript levels that persist for at least 48 h after single exposures between 0.5 and 10 Gy. Stable, non-responsive mRNA sequences for use as endogenous controls were also identified. These results indicate that following further

  8. Cutting Class Harms Grades

    Science.gov (United States)

    Taylor, Lewis A., III

    2012-01-01

    An accessible business school population of undergraduate students was investigated in three independent, but related studies to determine effects on grades due to cutting class and failing to take advantage of optional reviews and study quizzes. It was hypothesized that cutting classes harms exam scores, attending preexam reviews helps exam…

  9. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  10. Modelling of harmful effect of the combined environmental impacts of physical and chemical factors

    International Nuclear Information System (INIS)

    Paskalev, Z.

    1995-01-01

    Bio-physico-chemical mechanisms leading to pathological state of human organism caused by several simultaneously introduced harmful factors are discussed. A scheme of combined effect of two factors is proposed. An important element in determining the resulting effect is the conjuction of the development of biological effect and recovery process. An equation describing the change in biological system state is given taking into account the duration of impact, time interval, function of recovery and number of repetition of impacts. Two kind of investigations are considered for establishing the degree of harmful impacts: experimental and epidemiological. The results are given of author's experiments on rats with phosalon pesticide (chemical factor) and internal irradiation from the beta emitters 89 Sr and 144 Ce (physical factors), introduced separately and in combination. The change in the serum cholinesterase and amylase have been used as criteria for harmful impacts. Data from epidemiological studies in Bulgaria are also presented showing an increase in morbidity of the population connected with the combined influence of various radiation and non radiation factors. 3 tabs., 6 figs., 8 refs

  11. ASPIRE: An automated sample positioning and irradiation system for radiation biology experiments at Inter University Accelerator Centre, New Delhi

    International Nuclear Information System (INIS)

    Kothari, Ashok; Barua, P.; Archunan, M.; Rani, Kusum; Subramanian, E.T.; Pujari, Geetanjali; Kaur, Harminder; Satyanarayanan, V.V.V.; Sarma, Asitikantha; Avasthi, D.K.

    2015-01-01

    An automated irradiation setup for biology samples has been built at Inter University Accelerator Centre (IUAC), New Delhi, India. It can automatically load and unload 20 biology samples in a run of experiment. It takes about 20 min [2% of the cell doubling time] to irradiate all the 20 samples. Cell doubling time is the time taken by the cells (kept in the medium) to grow double in numbers. The cells in the samples keep growing during entire of the experiment. The fluence irradiated to the samples is measured with two silicon surface barrier detectors. Tests show that the uniformity of fluence and dose of heavy ions reaches to 2% at the sample area in diameter of 40 mm. The accuracy of mean fluence at the center of the target area is within 1%. The irradiation setup can be used to the studies of radiation therapy, radiation dosimetry and molecular biology at the heavy ion accelerator. - Highlights: • Automated positioning and irradiation setup for biology samples at IUAC is built. • Loading and unloading of 20 biology samples can be automatically carried out. • Biologicals cells keep growing during entire experiment. • Fluence and dose of heavy ions are measured by two silicon barrier detectors. • Uniformity of fluence and dose of heavy ions at sample position reaches to 2%

  12. RBE [relative biological effectiveness] of tritium beta radiation to gamma radiation and x-rays analyzed by both molecular and genetic methods

    International Nuclear Information System (INIS)

    Lee, W.R.

    1988-01-01

    The relative biological effectiveness (RBE) of tritium beta radiation to 60 Co gamma radiation was determined using sex-linked recessive lethals (SLRL) induced in Drosophila melanogaster spermatozoa as the biological effect. The SLRL test, a measure of mutations induced in germ cells transmitted through successive generations, yields a linear dose-response curve in the range used in these experiments. From these ratios of the slopes of the 3 H beta and the 60 Co gamma radiation linear dose response curves, an RBE of 2.7 is observed. When sources of error are considered, this observation suggests that the tritium beta particle is 2.7 ± 0.3 times more effective per unit of energy absorbed in inducing gene mutations transmitted to successive generation than 60 Co gamma radiation. Ion tracks with a high density of ions (high LET) are more efficient than tracks with a low ion density (low LET) in inducing transmissible mutations, suggesting interaction among products of ionization. Molecular analysis of x-ray induced mutations shows that most mutations are deletions ranging from a few base pairs as determined from sequence data to multi locus deletions as determined from complementation tests and Southern blots. 14 refs., 1 fig

  13. Modeling marrow damage from response data: Morphallaxis from radiation biology to benzene toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Jones, T.D.; Morris, M.D.; Hasan, J.S.

    1995-12-01

    Consensus principles from radiation biology were used to describe a generic set of nonlinear, first-order differential equations for modeling of toxicity-induced compensatory cell kinetics in terms of sublethal injury, repair, direct killing, killing of cells with unrepaired sublethal injury, and repopulation. This cellular model was linked to a probit model of hematopoietic mortality that describes death from infection and/or hemorrhage between {approximately} 5 and 30 days. Mortality data from 27 experiments with 851 doseresponse groups, in which doses were protracted by rate and/or fractionation, were used to simultaneously estimate all rate constants by maximum-likelihood methods. Data used represented 18,940 test animals distributed according to: (mice, 12,827); (rats, 2,925); (sheep, 1,676); (swine, 829); (dogs, 479); and (burros, 204). Although a long-term, repopulating hematopoietic stem cell is ancestral to all lineages needed to restore normal homeostasis, the dose-response data from the protracted irradiations indicate clearly that the particular lineage that is ``critical`` to hematopoietic recovery does not resemble stem-like cells with regard to radiosensitivity and repopulation rates. Instead, the weakest link in the chain of hematopoiesis was found to have an intrinsic radioresistance equal to or greater than stromal cells and to repopulate at the same rates. Model validation has been achieved by predicting the LD{sub 50} and/or fractional group mortality in 38 protracted-dose experiments (rats and mice) that were not used in the fitting of model coefficients.

  14. Green algae in alpine biological soil crust communities: acclimation strategies against ultraviolet radiation and dehydration.

    Science.gov (United States)

    Karsten, Ulf; Holzinger, Andreas

    2014-01-01

    Green algae are major components of biological soil crusts in alpine habitats. Together with cyanobacteria, fungi and lichens, green algae form a pioneer community important for the organisms that will succeed them. In their high altitudinal habitat these algae are exposed to harsh and strongly fluctuating environmental conditions, mainly intense irradiation, including ultraviolet radiation, and lack of water leading to desiccation. Therefore, green algae surviving in these environments must have evolved with either avoidance or protective strategies, as well as repair mechanisms for damage. In this review we have highlighted these mechanisms, which include photoprotection, photochemical quenching, and high osmotic values to avoid water loss, and in some groups flexibility of secondary cell walls to maintain turgor pressure even in water-limited situations. These highly specialized green algae will serve as good model organisms to study desiccation tolerance or photoprotective mechanisms, due to their natural capacity to withstand unfavorable conditions. We point out the urgent need for modern phylogenetic approaches in characterizing these organisms, and molecular methods for analyzing the metabolic changes involved in their adaptive strategies.

  15. Modeling marrow damage from response data: Morphallaxis from radiation biology to benzene toxicity

    International Nuclear Information System (INIS)

    Jones, T.D.; Morris, M.D.; Hasan, J.S.

    1995-01-01

    Consensus principles from radiation biology were used to describe a generic set of nonlinear, first-order differential equations for modeling of toxicity-induced compensatory cell kinetics in terms of sublethal injury, repair, direct killing, killing of cells with unrepaired sublethal injury, and repopulation. This cellular model was linked to a probit model of hematopoietic mortality that describes death from infection and/or hemorrhage between ∼ 5 and 30 days. Mortality data from 27 experiments with 851 doseresponse groups, in which doses were protracted by rate and/or fractionation, were used to simultaneously estimate all rate constants by maximum-likelihood methods. Data used represented 18,940 test animals distributed according to: (mice, 12,827); (rats, 2,925); (sheep, 1,676); (swine, 829); (dogs, 479); and (burros, 204). Although a long-term, repopulating hematopoietic stem cell is ancestral to all lineages needed to restore normal homeostasis, the dose-response data from the protracted irradiations indicate clearly that the particular lineage that is ''critical'' to hematopoietic recovery does not resemble stem-like cells with regard to radiosensitivity and repopulation rates. Instead, the weakest link in the chain of hematopoiesis was found to have an intrinsic radioresistance equal to or greater than stromal cells and to repopulate at the same rates. Model validation has been achieved by predicting the LD 50 and/or fractional group mortality in 38 protracted-dose experiments (rats and mice) that were not used in the fitting of model coefficients

  16. Biosensors for Real-Time Monitoring of Radiation-Induced Biologic Effects in Space

    Science.gov (United States)

    Baker, James R.; Balogh, Lajos; Majoros, Istvan; Keszler, Balazs; Myc, Andrzej; Kukowska-Latallo, Jolanta; Norris, Theodore; delaiglesia, Felix; Beeson, Nicholas W. (Compiler)

    2002-01-01

    This work seeks to develop cellular biosensors based on dendritic polymers. Nanoscale polymer structures less than 20 nm in diameter will be used as the basis of the biosensors. The structures will be designed to target into specific cells of an astronaut and be able to monitor health issues such as exposure to radiation. Multiple components can be assembled on the polymers including target directors, analytical devices (such as molecular probes), and reporting agents. The reporting will be accomplished through fluorescence signal monitoring, with the use of multispectral analysis for signal interpretation. These nanosensors could facilitate the success and increase the safety of extended space flight. The design and assembly of these devices has been pioneered at the Center for Biologic Nanotechnology in the University of Michigan. This period, synthesis of the test-bed biosensors continued. Studies were performed on the candidate fluorescent dyes to determine which might be suitable for the biosensor under development. Development continued on producing an artificial capillary bed as a tool for the use in the production of the fluorescence signal monitor. Work was also done on the in vitro multispectral analysis system, which uses the robotic microscope.

  17. Master of Science (MSc Program in Radiation Biology: An Interdepartmental Course Bridging the Gap between Radiation-Related Preclinical and Clinical Disciplines to Prepare Next-Generation Medical Scientists

    Directory of Open Access Journals (Sweden)

    Stephanie E. Combs

    2017-09-01

    Full Text Available Radiation biology is a highly interdisciplinary field at the interface of biology, physics, and medicine. It is characterized by rapid advances in biological and technical knowledge. The potential for using these advances to optimize medical care, radiation protection, and related fields can be exploited only with complementary activities to support the education of young academics. A small number of academic institutions have committed resources into radiation-related courses and curricula; however, few offer a comprehensive interdepartmental research and training program. At the Technical University of Munich (TUM, a full Master of Science (MSc course in radiation biology has been established. This article describes the TUM MSc radiation biology program, discusses the scope of the field, the teaching goals, and the interdisciplinary curriculum. Detailed information on the full MSc program can be found continuously updated at www.radonc.med.tum.de/masterradiationbiology.

  18. Master of Science (MSc) Program in Radiation Biology: An Interdepartmental Course Bridging the Gap between Radiation-Related Preclinical and Clinical Disciplines to Prepare Next-Generation Medical Scientists.

    Science.gov (United States)

    Combs, Stephanie E; Kessel, Carmen; Wilkens, Jan J; Multhoff, Gabriele; Schmid, Thomas E; Vaupel, Peter; Trott, Klaus-Rüdiger; Berberat, Pascal; Atkinson, Michael J

    2017-01-01

    Radiation biology is a highly interdisciplinary field at the interface of biology, physics, and medicine. It is characterized by rapid advances in biological and technical knowledge. The potential for using these advances to optimize medical care, radiation protection, and related fields can be exploited only with complementary activities to support the education of young academics. A small number of academic institutions have committed resources into radiation-related courses and curricula; however, few offer a comprehensive interdepartmental research and training program. At the Technical University of Munich (TUM), a full Master of Science (MSc) course in radiation biology has been established. This article describes the TUM MSc radiation biology program, discusses the scope of the field, the teaching goals, and the interdisciplinary curriculum. Detailed information on the full MSc program can be found continuously updated at www.radonc.med.tum.de/masterradiationbiology.

  19. Outcome of radiation biology in radiotherapy. Past and future directions; Applications cliniques des recherches en radiobiologie. Etat des lieux et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Hennequin, C. [Hopital Saint-Louis, Service d' Oncologie-Radiotherapie, 75 - Paris (France); Favaudon, V. [Centre Universitaire d' Orsay, Institut Curie, Section de Recherche, Lab. Raymond-Latarjet, Unite 350 Inserm, 91 (France)

    2000-10-01

    Over the last ten years the impact of fundamental radiation biology into daily radiotherapy has been of concern chiefly to fractionation, prediction of radiation response, tumour oxygenation, intrinsic radiosensitivity including genetic approaches, and the determinants of the outcome of chemoradiotherapy combinations. Future goals will rely on sophisticated approaches, based on the progress of molecular and cellular biology and the characterization of new targets for radiation. Some of these novel advances will be discussed. (authors)

  20. Microbeam radiation therapy. Physical and biological aspects of a new cancer therapy and development of a treatment planning system

    Energy Technology Data Exchange (ETDEWEB)

    Bartzsch, Stefan

    2014-11-05

    Microbeam Radiation Therapy (MRT) is a novel treatment strategy against cancer. Highly brilliant synchrotron radiation is collimated to parallel, a few micrometre wide, planar beams and used to irradiate malignant tissues with high doses. The applied peak doses are considerably higher than in conventional radiotherapy, but valley doses between the beams remain underneath the established tissue tolerance. Previous research has shown that these beam geometries spare normal tissue, while being effective in tumour ablation. In this work physical and biological aspects of the therapy were investigated. A therapy planning system was developed for the first clinical treatments at the European Synchrotron Radiation Facility in Grenoble (France) and a dosimetry method based on radiochromic films was created to validate planned doses with measurements on a micrometre scale. Finally, experiments were carried out on a cellular level in order to correlate the physically planned doses with the biological damage caused in the tissue. The differences between Monte Carlo dose and dosimetry are less than 10% in the valley and 5% in the peak regions. Developed alternative faster dose calculation methods deviate from the computational intensive MC simulations by less than 15% and are able to determine the dose within a few minutes. The experiments in cell biology revealed an significant influence of intercellular signalling on the survival of cells close to radiation boundaries. These observations may not only be important for MRT but also for conventional radiotherapy.

  1. Backscatter radiation at tissue-titanium interfaces; Biological effects from diagnostic 65 kVp X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Rosengren, B. (Department of Radiation Sciences, Uppsala University (Sweden) Dept. of Oncology, University Hospital, Bergen (Norway)); Wulff, L. (Dept. of Oral and Maxillofacial Surgery, Central Hospital, Boden (Sweden)); Carlsson, E. (Department of Radiation Sciences, Uppsala University (Sweden)); Carlsson, J. (Department of Radiation Sciences, Uppsala University (Sweden)); Strid, K.G. (Dept. of Handicap Research, Goeteborg Univ. (Sweden)); Montelius, A. (Dept. of Hospital Physics, University Hospital, Uppsala (Sweden))

    1993-01-01

    The induced secondary electrons from a metal surface by diagnostic X-rays are thought to contribute to cell damage near the tissue-metal boundaries of metal implants. Titanium implants are becoming increasingly more popular for tissue reconstructions and it is rather often desirable to take radiographs of the operated area. In this study we compared the biological effects of radiation on cultured mammalian test cells grown on titanium plates with the radiation effects on cells that were grown on plastic control plates. In order to study the acute radiation effects on cell growth it was necessary to work with rather high radiation doses (0.7-5 Gy). Photon energies, suitable for diagnostic radiography in odontology, 65 kV, were applied. We found that the cells grown on titanium plates were, in terms of the applied dose in the surrounding culture medium, more sensitive to the irradiations than the cells growing on plastic plates. The survival curve for the cells on titanium had a steeper slope, showed no shoulder in the low-dose region and looked like curves normally obtained for high LET radiation. It was not possible to resolve to what degree the titanium-dependent changes were due to an increased dose near the titanium surface or to a change in the radiobiological effectiveness. Although there was a significant decrease in cellular survival near the metal, postoperative intraoral radiography after titanium implantations need not be excluded. The maximal doses given in odontological X-ray examinations are less than 1 mGy and, if the results in this study are applied, the biological effects near the titanium implant will correspond to biological effects in soft tissue of doses less than 20 mGy which is lower than the doses that give acute effects. The risk of acute healing disturbances are significant only at much higher radiation doses. (orig.).

  2. Mathematical model for evaluation of dose-rate effect on biological responses to low dose γ-radiation

    International Nuclear Information System (INIS)

    Ogata, H.; Kawakami, Y.; Magae, J.

    2003-01-01

    Full text: To evaluate quantitative dose-response relationship on the biological response to radiation, it is necessary to consider a model including cumulative dose, dose-rate and irradiation time. In this study, we measured micronucleus formation and [ 3 H] thymidine uptake in human cells as indices of biological response to gamma radiation, and analyzed mathematically and statistically the data for quantitative evaluation of radiation risk at low dose/low dose-rate. Effective dose (ED x ) was mathematically estimated by fitting a general function of logistic model to the dose-response relationship. Assuming that biological response depends on not only cumulative dose but also dose-rate and irradiation time, a multiple logistic function was applied to express the relationship of the three variables. Moreover, to estimate the effect of radiation at very low dose, we proposed a modified exponential model. From the results of fitting curves to the inhibition of [ 3 H] thymidine uptake and micronucleus formation, it was obvious that ED 50 in proportion of inhibition of [ 3 H] thymidine uptake increased with longer irradiation time. As for the micronuclei, ED 30 also increased with longer irradiation times. These results suggest that the biological response depends on not only total dose but also irradiation time. The estimated response surface using the three variables showed that the biological response declined sharply when the dose-rate was less than 0.01 Gy/h. These results suggest that the response does not depend on total cumulative dose at very low dose-rates. Further, to investigate the effect of dose-rate within a wider range, we analyzed the relationship between ED x and dose-rate. Fitted curves indicated that ED x increased sharply when dose-rate was less than 10 -2 Gy/h. The increase of ED x signifies the decline of the response or the risk and suggests that the risk approaches to 0 at infinitely low dose-rate

  3. 5. Conference cycle. The radiations and the Biological Sciences; 5. Ciclo de conferencias. Las radiaciones y las Ciencias Biologicas

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar G, M.; Chavez B, A

    1991-06-15

    Nuclear technologies and their development have influenced many aspects of modern life. Besides used for electricity production nuclear technologies are applied in many other fields, especially in biological sciences. In genetics and molecular biology they enable research resulting in increased food production and better food preservation. Usage in material sciences lead to new varieties of plastics or improved characteristics. Nuclear applications are used in pe troleum industries and in forecasting geothermic power. Radiobiology and radiotherapy enable diagnosis and therapy of several diseases, e.g. cancer. Nuclear technologies also contribute to preserve the environment. They offer methods to analyse as well as decrease the environmental impacts. The 5. conference cyle entitled 'The Radiations and the Biological Sciences' aims to inform students of biological sciences about new nuclear technologies applied in their field of interest.

  4. Islam and harm reduction.

    Science.gov (United States)

    Kamarulzaman, A; Saifuddeen, S M

    2010-03-01

    Although drugs are haram and therefore prohibited in Islam, illicit drug use is widespread in many Islamic countries throughout the world. In the last several years increased prevalence of this problem has been observed in many of these countries which has in turn led to increasing injecting drug use driven HIV/AIDS epidemic across the Islamic world. Whilst some countries have recently responded to the threat through the implementation of harm reduction programmes, many others have been slow to respond. In Islam, The Quran and the Prophetic traditions or the Sunnah are the central sources of references for the laws and principles that guide the Muslims' way of life and by which policies and guidelines for responses including that of contemporary social and health problems can be derived. The preservation and protection of the dignity of man, and steering mankind away from harm and destruction are central to the teachings of Islam. When viewed through the Islamic principles of the preservation and protection of the faith, life, intellect, progeny and wealth, harm reduction programmes are permissible and in fact provide a practical solution to a problem that could result in far greater damage to the society at large if left unaddressed. Copyright (c) 2009. Published by Elsevier B.V.

  5. Mammography screening. Benefits, harms, and informed choice

    DEFF Research Database (Denmark)

    Jørgensen, Karsten Juhl

    2013-01-01

    the justification of breast screening is therefore not a simple question of whether screening reduces breast cancer mortality. This dissertation quantifies the primary benefits and harms of screening mammography. Denmark has an unscreened "control group" because only two geographical regions offered screening over...... are overdiagnosed. An effect on breast cancer mortality is doubtful in today's setting, and overdiagnosis causes an increase in the use of mastectomies. These findings are discussed in the context of tumour biology and stage at diagnosis. The information provided to women in invitations and on the Internet...... exaggerates benefits, participation is directly recommended, and the harms are downplayed or left out, despite agreement that the objective is informed choice. This raises an ethical discussion concerning autonomy versus paternalism, and the difficulty in weighing benefits against harms. Finally, financial...

  6. Sensible biological models to be exposed to VDT (Video Display Terminal) radiations in human male reproduction

    International Nuclear Information System (INIS)

    Tritto, J.; North, M.-O.; Laverdure, A.M.; Surbeck, J.

    1999-01-01

    Temperature and environmental effects, particularly endocrine disrupters and EMF radiations, are actively investigated in human and non-human reproduction experimental models. Sensitivity and specificity of the different cell types of the testes seminiferous tubules in animals and in human are evaluated, showing a specific responsiveness of spermatogonia (SPG) and resting pachytene spermatocytes (SPC). At 32 o C the 24 h short-term cultures of biopsies of normal human testis show an expected low occurrence of apoptotic SPG (1 %) that increases to 3,4 % in peer samples exposed to VDT for the same period, with the appearance of apoptotic SPC (4,6 %). In samples from a thermically-impaired testis of the same subject the apoptotic occurrence of SPG is 2,6 % with 15,4 % for SPC after 24 h cultures. After 24 h exposure to VDT the apoptotic score is 7,6 % for SPG and 18,5 % for SPC in thermically impaired peer samples. With EMF-bioshields the apoptotic score for SPG is 0,8 % in normal 2,2 % for SPG and 13,8 % for SPC in T-impaired peer-samples. NMRS of the cultures fluids show a proportional production of lactate, corresponding to the different degrees of histopathological impairment of the samples. IVOS (Integrated Visual Optic System) analysis of sperm samples from thermically-impaired, not-repaired and repaired testes exposed to VDT shows sensible variations on straightness (STR), linearity (LIN) and lateral head displacement (LHD) parameters. To evaluate the thermic and non-thermic potential bioeffects of VDT on human spermatogenesis the specificity, the sensitivity and the reproducibility of the biological models on one side and the specificity of the methodologies on the other side must be provided. (author)

  7. Multi-mutational model for cancer based on age-time patterns of radiation effects: 2. Biological aspects

    Energy Technology Data Exchange (ETDEWEB)

    Mendelsohn, M.L.; Pierce, P.A.

    1997-09-04

    Biological properties of relevance when modeling cancers induced in the atom bomb survivors include the wide distribution of the induced cancers across all organs, their biological indistinguishability from background cancers, their rates being proportional to background cancer rates, their rates steadily increasing over at least 50 years as the survivors age, and their radiation dose response being linear. We have successfully described this array of properties with a modified Armitage-Doll model using 5 to 6 somatic mutations, no intermediate growth, and the dose-related replacement of any one of these time-driven mutations by a radiation-induced mutation. Such a model is contrasted to prevailing models that use fewer mutations combined with intervening growth. While the rationale and effectiveness of our model is compelling for carcinogenesis in the atom bomb survivors, the lack of a promotional component may limit the generality of the model for other types of human carcinogenesis.

  8. Human exposure to radiation following the release of radioactivity from a reactor accident: a quantitative assessment of the biological consequences

    International Nuclear Information System (INIS)

    Smith, H.; Stather, J.W.

    1976-11-01

    The objective of this review is to provide a biological basis upon which to assess the consequences of the exposure of a population to radioactivity released after a reactor accident. Depending upon the radiation dose, both early and late somatic damage could occur in the exposed population and hereditary effects may occur in their descendants. The development of dose-effect relationships has been based upon the limited amount of information available on humans, supplemented by data obtained from experiments on animals. (author)

  9. Overview of research in radiation biology and protective measures in the Manhattan Project during the war years, 1942-1946

    International Nuclear Information System (INIS)

    Friedell, H.L.

    The objecitve was to present a cohesive view of the general biological research program associated with the Manhattan Project. The material is arrangd in chronological order. Each of the major research sites is identified and the general nature of their research program indicated. A section is devoted to the question of the various radiation limits which were used in the operational approach to hazard controls

  10. Absorption coefficient measurrement of monochromatized synchrotron radiation at 0.65 - 1.3 A interval for some biological objects

    International Nuclear Information System (INIS)

    Avakian, Ts.M.; Karabekov, I.P.; Martirossian, M.A.

    1977-01-01

    The results of the measurement of absorption coefficients for some biological objects such as pea (Pissum sativum), wheat (Triticum aestivum), tobacco (Nicotiana-tabacum-α) seeds, as well as the distilled water are presented. The measurement has been carried out on the Erevan Physical Institute Electron Accelerator synchrotron radiation beam. The good agreement of experimental and calculated data for water confirms the accuracy of the results related to other objects

  11. A review of biological effects and potential risks associated with ultraviolet radiation as used in dentistry. Technical report

    International Nuclear Information System (INIS)

    Mills, L.F.; Lytle, C.D.; Andersen, F.A.; Hellman, K.B.; Bockstahler, L.E.

    1975-10-01

    Several dental procedures, recently developed and currently in use by the dental profession, involve the use of near or far ultraviolet (UV) radiation in the oral cavity. Recent studies on the biological effects of near and far UV radiation suggest potential risks to individuals from excessive UV exposure. In this paper the dental procedures are briefly described, the bases for UV safety standards are reviewed, effects of UV exposure to the skin and eyes and how these effects may relate to oral mucosa exposure are considered, potential modes of action by UV radiation on oral tissues as suggested by cell culture studies are summarized, and potential risks from UV exposure of individuals which might result from the dental procedures are discussed

  12. Analysis behaviour of free radicals produced by ionizing radiations in human blood by EPR for biological dosimetry in patients

    International Nuclear Information System (INIS)

    Mendoza, O. O.; Almanza, A.; Plazas, M. M. C.

    2006-01-01

    In this work is analyzed the biological dosimetry of the free radicals produced by ionizing radiations in human blood obtained by EPR and the biological behaviour of samples In-Vitro, with Rh: O+, in tubes with EDTA (Acid Etilen Diamino Tetracetic) the samples was extracted of the main investigator, these samples were radiated with gammas of ''60Co of a Theratron 780 between plates of PMMA to a depth of Z m ax of 0.5 cm and between doses 1 to 25 Gy. In these results the behaviors of signal the free radicals presented a increasing a their intensity depending on applied dose, of equal way are results of the biologic dosimetry displayed in sanguineous populations like. White Globules, Red. Platelets etc, to being compared with Resonance Paramagnetic Electronic (EPR). The results show changes in sanguineous populations in high doses (D>10 Gy) in the case of lymphocytes, granulocitos, macusanita, plaquetas, hemoglobina, haematocrit with change similarly in medium and low doses (D>10Gy) in linfocites, platelets, granulocytes, monocytes and the haematocrit. A sanguineous sample without radiating analyzes by EPR giving the presence of signals with values of g=2.13 2,41 in blood. For the first certain value of g authors have associated it to free radicals like: globin (Fe(IV)=0) or Cu''+ incorporated to the ceruloplasmin molecule. (Author)

  13. Biological in situ Dose Painting for Image-Guided Radiation Therapy Using Drug-Loaded Implantable Devices

    International Nuclear Information System (INIS)

    Cormack, Robert A.; Sridhar, Srinivas; Suh, W. Warren; D'Amico, Anthony V.; Makrigiorgos, G. Mike

    2010-01-01

    Purpose: Implantable devices routinely used for increasing spatial accuracy in modern image-guided radiation treatments (IGRT), such as fiducials or brachytherapy spacers, encompass the potential for in situ release of biologically active drugs, providing an opportunity to enhance the therapeutic ratio. We model this new approach for two types of treatment. Methods and Materials: Radiopaque fiducials used in IGRT, or prostate brachytherapy spacers ('eluters'), were assumed to be loaded with radiosensitizer for in situ drug slow release. An analytic function describing the concentration of radiosensitizer versus distance from eluters, depending on diffusion-elimination properties of the drug in tissue, was developed. Tumor coverage by the drug was modeled for tumors typical of lung stereotactic body radiation therapy treatments for various eluter dimensions and drug properties. Six prostate 125 I brachytherapy cases were analyzed by assuming implantation of drug-loaded spacers. Radiosensitizer-induced subvolume boost was simulated from which biologically effective doses for typical radiosensitizers were calculated in one example. Results: Drug distributions from three-dimensional arrangements of drug eluters versus eluter size and drug properties were tabulated. Four radiosensitizer-loaded fiducials provide adequate radiosensitization for ∼4-cm-diameter lung tumors, thus potentially boosting biologically equivalent doses in centrally located stereotactic body treated lesions. Similarly, multiple drug-loaded spacers provide prostate brachytherapy with flexible shaping of 'biologically equivalent doses' to fit requirements difficult to meet by using radiation alone, e.g., boosting a high-risk region juxtaposed to the urethra while respecting normal tissue tolerance of both the urethra and the rectum. Conclusions: Drug loading of implantable devices routinely used in IGRT provides new opportunities for therapy modulation via biological in situ dose painting.

  14. Ionizing radiation

    International Nuclear Information System (INIS)

    Kruger, J.

    1989-01-01

    Ionizing radiation results in biological damage that differs from other hazardous substances and is highly dangerous to man. Ionizing radiation cannot be perceived by man's sense organs and the biological damage cannot be detected immediately afterwards (except in very high doses). Every human being is exposed to low doses of radiation. The structure of the atom; sources of ionizing radiation; radiation units; biological effects; norms for radiation protection; and the national control in South Africa are discussed. 1 fig., 5 refs

  15. Radiation effects and radioprotectors

    International Nuclear Information System (INIS)

    Purohit, R.K.; Bugalia, Saroj; Dakshene, Monika

    2012-01-01

    Radiation exposure causes damage to biological systems and these damages are mediated by the generation of free radicals and reactive oxygen species targeting vital cellular components such as DNA and membranes. DNA repair systems and the endogenous cellular biochemical defense mechanisms against reactive oxygen species and antioxidants enzymes like reduced Glutathione (GSH), Superoxide dismutase, Glutathione peroxidase catalase etc. fail upon exposures to higher as well as chronic radiation doses leading to alterations in cell functions, cell death or mutations. Radioprotectors prevent these alterations and protect cells and tissues from the deleterious effects of radiations. Radioprotectors are of great importance due to their possible and potential application during planned radiation exposures such as radiotherapy, diagnostic scanning, clean up operations in nuclear accidents, space expeditions etc. and Unplanned radiations exposures such as accidents in nuclear industry, nuclear terrorism, natural background radiation etc. Many of the available synthetic radioprotectors are toxic to mammalian system at doses required to be effective as radioprotector. Increasing uses of ionizing radiation have drawn the attention of many radiobiologists towards their undesired side effects produced in various tissues and for modifying them to facilitate the beneficial uses of radiation. Modification of radiation response is obtained by means of chemical substances that can significantly decrease the magnitude of response when present in a biological system during irradiation. Radioprotectors are chemicals that modify a cell's response to radiation. Radioprotectors are drugs that protect normal (non cancerous) cells from the damage caused by radiation therapy. These agents promote the repair of normal cells that are exposed to radiation. Various chemicals, like Cysteamine, MPG , WR-2721 have been tested for the protection against harmful effects of radiation. These radio

  16. THE HIGH BACKGROUND RADIATION AREA IN RAMSAR IRAN: GEOLOGY, NORM, BIOLOGY, LNT, AND POSSIBLE REGULATORY FUN

    Energy Technology Data Exchange (ETDEWEB)

    Karam, P. A.

    2002-02-25

    The city of Ramsar Iran hosts some of the highest natural radiation levels on earth, and over 2000 people are exposed to radiation doses ranging from 1 to 26 rem per year. Curiously, inhabitants of this region seem to have no greater incidence of cancer than those in neighboring areas of normal background radiation levels, and preliminary studies suggest their blood cells experience fewer induced chromosomal abnormalities when exposed to 150 rem ''challenge'' doses of radiation than do the blood cells of their neighbors. This paper will briefly describe the unique geology that gives Ramsar its extraordinarily high background radiation levels. It will then summarize the studies performed to date and will conclude by suggesting ways to incorporate these findings (if they are borne out by further testing) into future radiation protection standards.

  17. Cancer and non-cancer risk at low doses of radiation: biological basis of radiation-environment interplay

    International Nuclear Information System (INIS)

    Sasaki, Masao S.

    2013-01-01

    Cancer and non-cancer risk at low doses of ionizing radiation remains poorly defined due to ambiguity at low doses caused by limitations in statistical power and information available on interplay with environment. To deal with these problems, a novel non-parametric statistics was developed based on artificial neural networks theorem and applied to cancer and non-cancer risk in A-bomb survivors. The analysis revealed several unique features at low doses that could not be accounted for by nominal radiation dose alone. They include (1) threshold that varies with organ, gender and age, including cardiovascular diseases, (2) prevalence of infectious diseases, and (3) suppression of pathogenesis of HTLV1. The threshold is unique as it is manifested as negative excess relative risk, a reduction of spontaneous rate at low doses. The response is consistent with currently emerging laboratory data on DNA double-strand break (DSB) repair pathway choice and its sustainability as epigenetic memory in accordance with histone code theory. In response to DSB, of radiation or DNA replication arrest origin, distinct and competitively operating repair pathways are instigated. Activation by low doses of restitution-directed canonical non-homologous end-joining (C-NHEJ) suppresses both error-prone alternative end-joining (Alt-NHEJ) and homologous recombination (HR). The latter two present major pathways to mutagenesis at stalled replication folk associated with endogenous and exogenous genotoxin such as tobacco smoke metabolites and AID-associated somatic hypermutation and class switch recombination in Ig gene. Suppression of these error-prone pathways by low doses of low LET radiation is consistent with the reduction of cancer occurrence by environmental genotoxin, immunodiversity and stable integration of retrovirus DNA, providing a significant modulator of dose linearity at low doses. Whole picture may bring about a new landscape of cancer and non-cancer molecular epidemiology which

  18. Radiation biophysicl study of biological molecules. Progress report, February 1, 1975--June 30, 1976

    International Nuclear Information System (INIS)

    Fluke, D.J.

    1976-01-01

    Progress is reported on the following research projects: direct action target investigation of molecular weights of enzymes exposed to fast electrons; direct action gamma radiation dosimetry with T 1 bacteriophage; uv radiation sensitivity of T 1 bacteriophage on various host strains of E. coli; temperature dependence of uv radiation direct action on dry T 1 bacteriophage; investigation of light and temperature effects during incubation of T 1 bacteriophage exposed to fast electrons; test of superoxide anion as a radiation intermediate in cellular radiobiology; uv action spectra related to error-prone repair; uv-reactivation experiments with T 1 and lambda bacteriophages; and split-dose uv mutagenesis in E. coli

  19. Macrophage biology plays a central role during ionizing radiation-elicited tumor response

    Directory of Open Access Journals (Sweden)

    Qiuji Wu

    2017-08-01

    Full Text Available Radiation therapy is one of the major therapeutic modalities for most solid tumors. The anti-tumor effect of radiation therapy consists of the direct tumor cell killing, as well as the modulation of tumor microenvironment and the activation of immune response against tumors. Radiation therapy has been shown to promote immunogenic cells death, activate dendritic cells and enhance tumor antigen presentation and anti-tumor T cell activation. Radiation therapy also programs innate immune cells such as macrophages that leads to either radiosensitization or radioresistance, according to different tumors and different radiation regimen studied. The mechanisms underlying radiation-induced macrophage activation remain largely elusive. Various molecular players such as NF-κB, MAPKs, p53, reactive oxygen species, inflammasomes have been involved in these processes. The skewing to a pro-inflammatory phenotype thus results in the activation of anti-tumor immune response and enhanced radiotherapy effect. Therefore, a comprehensive understanding of the mechanism of radiation-induced macrophage activation and its role in tumor response to radiation therapy is crucial for the development of new therapeutic strategies to enhance radiation therapy efficacy.

  20. Casting light on harm reduction

    DEFF Research Database (Denmark)

    Jourdan, Michael

    2009-01-01

    Background: Harm reduction is commonly regarded as complementary to other drug problem responses - as the fourth tier. Yet even core examples of harm reduction such as the provision of injection equipment and methadone treatment has over and over encountered considerable opposition, and harm...

  1. Alcohol harm reduction in Europe

    DEFF Research Database (Denmark)

    Herring, Rachel; Betsy, Thom; Beccaria, Franca

    2010-01-01

    The EMCDDA’s 10th scientific monograph, entitled Harm reduction: evidence, impacts and challenges provides a comprehensive overview of the harm reduction field. Part I of the monograph looks back at the emergence of harm reduction approaches and their diffusion, and explores the concept from diff...

  2. The principles of dose limitation in radiation protection

    International Nuclear Information System (INIS)

    Kaul, A.

    1988-01-01

    The aim of radiation protection is to protect individuals, their offspring and the population as a whole against harmful effects from ionizing radiation and radioactive substances. Harmful effects may be either somatic, i.e. occurring in the exposed person himself/herself, or hereditary, i.e. occurring in the exposed person's offspring. Successful radiation protection involves (a) protective measures based on the results of research into the biological and biophysical effects of radiation and (b) ensuring that activities necessitating exposure are justified and that the degree of exposure is minimal. This benefit/risk principle ceases to apply if a radiation source is out of control, since the main aim is then to introduce risk limitation measures, provided that these are of positive net benefit to the individual and the population as a whole. This paper discusses the principles of dose limitation as a function of exposure conditions, i.e. controlled or uncontrolled exposure to a source of radiation

  3. Biology

    Indian Academy of Sciences (India)

    I am particularly happy that the Academy is bringing out this document by Professor M S. Valiathan on Ayurvedic Biology. It is an effort to place before the scientific community, especially that of India, the unique scientific opportunities that arise out of viewing Ayurveda from the perspective of contemporary science, its tools ...

  4. Adverse event reporting and developments in radiation biology after normal tissue injury: International Atomic Energy Agency consultation

    International Nuclear Information System (INIS)

    Chen Yuhchyau; Trotti, Andy; Coleman, C. Norman; Machtay, Mitchell; Mirimanoff, Rene O.; Hay, John; O'Brien, Peter C.; El-Gueddari, Brahim; Salvajoli, Joao V.; Jeremic, Branislav

    2006-01-01

    Purpose: Recent research has enhanced our understanding of radiation injury at the molecular-cellular and tissue levels; significant strides have occurred in standardization of adverse event reporting in clinical trials. In response, the International Atomic Energy Agency, through its Division of Human Health and its section for Applied Radiation Biology and Radiotherapy, organized a consultation meeting in Atlanta (October 2, 2004) to discuss developments in radiobiology, normal tissue reactions, and adverse event reporting. Methods and Materials: Representatives from cooperative groups of African Radiation Oncology Group, Curriculo Radioterapeutica Ibero Latino Americana, European Organization for Research and Treatment of Cancer, National Cancer Institute of Canada Clinical Trials Group, Radiation Therapy Oncology Group, and Trans-Tasman Radiation Oncology Group held the meeting discussion. Results: Representatives of major radiotherapy groups/organizations and prominent leaders in radiotherapy discussed current understanding of normal tissue radiobiologic effects, the design and implementation of future clinical and translational projects for normal tissue injury, and the standardization of adverse-event reporting worldwide. Conclusions: The consensus was to adopt NCI comprehensive adverse event reporting terminology and grading system (CTCAE v3.0) as the new standard for all cooperative group trials. Future plans included the implementation of coordinated research projects focusing on normal tissue biomarkers and data collection methods

  5. MO-F-BRCD-01: Stereotactic Body Radiation Therapy: Updates on Clinical, Biological, and Physics/QA:SBRT (Part 1): Biological and Clinical Updates.

    Science.gov (United States)

    Read, P

    2012-06-01

    Stereotactic Body Radiation Therapy (SBRT) is an important form of cancer therapy with increasingly broad application across a spectrum of tumor types in primary and metastatic settings. In this presentation the radiation biology, clinical experience from various trials, and cautionary updates on normal tissue tolerances will be presented. The effective radiobiology of SBRT and hypofractionated courses of therapy has become more evident with the increasing reports of retrospective clinical outcomes and prospective clinical trial results. Current open multi-institutional national cooperative trials will be reviewed. Accumulating clinical experiences are yielding new insights into practical aspects of tumor and normal tissue responses to high dose per fraction treatment. Indeed, SBRT has produced profound tumoricidal and ablative effects, however there is potential for grave toxicity and this demands that clinicians be knowledgeable regarding normal tissue tolerances for various hypofractionated courses. As a final note, the technology associated with SBRT has evolved remarkably in the last decade, and procedures that originally required hours to plan, with cumbersome quality assurance methods, arduous set-up times, and long protracted deliveries can now be performed in ever shorter time periods. Given these technology improvements and recognizing the great palliative potential of hypofractionated radiation therapy to relieve cancer symptoms quickly and efficiently, a new strategy to deliver SBRT in a single session called STAT RAD is presented for discussion. © 2012 American Association of Physicists in Medicine.

  6. Comments on the theory of radiation risk II Experiments in biology and the assessment of radiation risk

    CERN Document Server

    Neufeld, J

    1974-01-01

    For pt. I see ibid., vol. 26, no.3, 229-37 (March 1974). An experimental program and a computational program are outlined for obtaining a relationship between transfer, L. Q and linear energy using biological data for critical effects and sets of linear equations can be obtained in which the coefficients are the doses delivered in intervals of L, and the unknowns are 'biological weighting factors', lambda . From these equations one can derive lambda 's for various L's as they relate to critical effects in animals. Using value judgment and combining the calculated results with data observed on men, one can obtain a Q-L relationship which is more directly based on experimental evidence than that which is currently used. (36 refs).

  7. The biological response of plucked human hair to low-dose radiation: a measure of individual radiosensitivity and a technique for biological dosimetry

    International Nuclear Information System (INIS)

    Swain, D.

    1997-01-01

    It is often assumed that the effects of radiation are linear with dose and that high dose effects can be extrapolated to low dose levels. However, there are a variety of mechanisms which can alter the response at low doses. The most important of these relate to induced sensitivity or induced repair mechanisms. It is therefore important that this area is studied in more depth by looking at the molecular effects and damage to cells at low doses. It is well known that there are certain rare genetic syndromes which predispose individuals to cancer, e.g. ataxia telangiectasia. It is also probable that there is a large range of sensitivity in the natural variation of individuals to the risk of radiation-induced cancer. It is proposed that radiosensitivity is studied using stimulated lymphocytes from whole blood and the technique extended to look at the effects in cell cultures established from human hair. Radiation treatment of cell cultures established from plucked human hair has been previously advocated as a non-invasive technique for non-uniform biological dosimetry and it is proposed that these techniques are adapted to the use of hair to estimate individual radiosensitivity. The aim is to establish and optimize these techniques for culturing keratinocytes from plucked human hair follicles with a view to study biological markers for the subsequent assessment of radiosensitivity. Preliminary results are promising and suggest that the technique for culturing keratinocytes from hair presents a feasible approach. Results from this primary cell culture technique and results from the comparison of the micronuclei data obtained from the cell cultures and stimulated lymphocytes will be presented. (author)

  8. Use of a biological marker in monitoring exposures among radiation workers

    International Nuclear Information System (INIS)

    Yulo-Nazarea, M.T.; Cobar, M.L.C.; Dy, R.

    1993-01-01

    With the introduction of more modern nuclear technology in nuclear medicine, there is an increased possibility for radiation exposure among workers handling nuclear materials which calls for the autoradiographic assay of Albertini's mutation assay for hypoxanthine guanine phosphoribosyl transferase (HGPRT). An in vivo somatic mutation of HGPRT gene due to radiation exposure could be assessed using this protocol. Favorable growth of lymphocytes in culture requires activated fetal bovine serum (FBS) in RPMI 1640 medium. Phytohemagglutinin (PHA) specifically stimulates maximum proliferation of lymphocytes. Thioguanine, an anti proliferative agent, was used to screen for the presence of mutation at the HGPRT gene in which cells having mutation at the HGPRT gene locus survive the inhibitive condition. Twenty-three samples were analyzed from radiation (14) and non-radiation (9) workers. Mutation index values greater than 0.4 have been found to be higher among radiation workers (21%) than among non-radiation workers (11%). The study will facilitate the screening procedure for radiation workers and thus prevent overexposure to radiation among workers. (author.). 8 refs.; 4 tabs

  9. Quantification of ultraviolet photon emission from interaction of charged particles in materials of interest in radiation biology research

    Science.gov (United States)

    Ahmad, Syed Bilal; McNeill, Fiona E.; Prestwich, William V.; Byun, Soo Hyun; Seymour, Colin; Mothersill, Carmel E.

    2014-01-01

    In radiation biology experiments often cells are irradiated using charged particles with the intention that only a specified number of cells are hit by the primary ion track. However, in doing so several other materials such as the cell container and the growth media etc. are also irradiated, and UV radiation emitted from these materials can potentially interact with the cells. We have hypothesized that some "bystander effects" that are thought to be chemically mediated, may be, in fact, a physical effect, where UV is interacting with non-targeted cells. Based upon our hypothesis we quantified the emission of UV from Polypropylene, Mylar, Teflon, and Cellophane which are all commonly used materials in radiation biology experiments. Additionally we measured the NIST standard materials of Oyster tissue and Citrus leaves as these powdered materials are derived from living cells. Protons accelerated up to an energy of 2.2 MeV, in a 3 MV Van de Graff accelerator, were used for irradiation. Beam current was kept to 10 nA, which corresponds to a proton fluence rate of 2.7 × 1010 protons mm-2 s-1. All the materials were found to emit light at UV frequencies and intensities that were significant enough to conduct a further investigation for their biological consequences. Mylar and polypropylene are commonly used in radiation induced bystander effect studies and are considered to be non-fluorescent. However our study showed that this is not the case. Significant luminescence observed from the irradiated NIST standard reference materials for Oyster tissue and Citrus leaves verified that the luminescence emission is not restricted only to the polymeric materials that are used to contain cells. It can also occur from ion interactions within the cells as well.

  10. Quantification of ultraviolet photon emission from interaction of charged particles in materials of interest in radiation biology research

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Syed Bilal, E-mail: ahmadsb@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Department of Physics and Applied Mathematics, Pakistan Institute of Engineering and Applied Sciences, Islamabad (Pakistan); McNeill, Fiona E., E-mail: fmcneill@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Prestwich, William V., E-mail: prestwic@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Byun, Soo Hyun, E-mail: soohyun@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Seymour, Colin, E-mail: seymouc@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Mothersill, Carmel E., E-mail: mothers@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada)

    2014-01-15

    In radiation biology experiments often cells are irradiated using charged particles with the intention that only a specified number of cells are hit by the primary ion track. However, in doing so several other materials such as the cell container and the growth media etc. are also irradiated, and UV radiation emitted from these materials can potentially interact with the cells. We have hypothesized that some “bystander effects” that are thought to be chemically mediated, may be, in fact, a physical effect, where UV is interacting with non-targeted cells. Based upon our hypothesis we quantified the emission of UV from Polypropylene, Mylar, Teflon, and Cellophane which are all commonly used materials in radiation biology experiments. Additionally we measured the NIST standard materials of Oyster tissue and Citrus leaves as these powdered materials are derived from living cells. Protons accelerated up to an energy of 2.2 MeV, in a 3 MV Van de Graff accelerator, were used for irradiation. Beam current was kept to 10 nA, which corresponds to a proton fluence rate of 2.7 × 10{sup 10} protons mm{sup −2} s{sup −1}. All the materials were found to emit light at UV frequencies and intensities that were significant enough to conduct a further investigation for their biological consequences. Mylar and polypropylene are commonly used in radiation induced bystander effect studies and are considered to be non-fluorescent. However our study showed that this is not the case. Significant luminescence observed from the irradiated NIST standard reference materials for Oyster tissue and Citrus leaves verified that the luminescence emission is not restricted only to the polymeric materials that are used to contain cells. It can also occur from ion interactions within the cells as well.

  11. Occupational cosmic radiation exposure in Portuguese airline pilots: study of a possible correlation with oxidative biological markers.

    Science.gov (United States)

    Silva, Rodrigo; Folgosa, Filipe; Soares, Paulo; Pereira, Alice S; Garcia, Raquel; Gestal-Otero, Juan Jesus; Tavares, Pedro; Gomes da Silva, Marco D R

    2013-05-01

    Several studies have sought to understand the health effects of occupational exposure to cosmic radiation. However, only few biologic markers or associations with disease outcomes have so far been identified. In the present study, 22 long- and 26 medium-haul male Portuguese airline pilots and 36 factory workers who did not fly regularly were investigated. The two groups were comparable in age and diet, were non-smokers, never treated with ionizing radiation and other factors. Cosmic radiation exposure in pilots was quantified based on direct monitoring of 51 flights within Europe, and from Europe to North and South America, and to Africa. Indirect dose estimates in pilots were performed based on the SIEVERT (Système informatisé d'évaluation par vol de l'exposition au rayonnement cosmique dans les transports aériens) software for 6,039 medium- and 1,366 long-haul flights. Medium-haul pilots had a higher cosmic radiation dose rate than long-haul pilots, that is, 3.3 ± 0.2 μSv/h and 2.7 ± 0.3 μSv/h, respectively. Biological tests for oxidative stress on blood and urine, as appropriate, at two time periods separated by 1 year, included measurements of antioxidant capacity, total protein, ferritin, hemoglobin, creatinine and 8-hydroxy-2-deoxyguanosine (8OHdG). Principal components analysis was used to discriminate between the exposed and unexposed groups based on all the biological tests. According to this analysis, creatinine and 8OHdG levels were different for the pilots and the unexposed group, but no distinctions could be made among the medium- and the long-haul pilots. While hemoglobin levels seem to be comparable between the studied groups, they were directly correlated with ferritin values, which were lower for the airline pilots.

  12. Late health effects of radiation exposure: new statistical, epidemiological, and biological approaches.

    Science.gov (United States)

    Jacob, Peter; Stram, Daniel O

    2013-08-01

    The 2012 Conference on Radiation and Health in Kennebunkport, Maine, USA, brought together epidemiologists, statisticians, basic scientists, and clinical scientists interested in the health effects of radiation exposure due to medical, diagnostic, occupational, and non-medical sources, to review the current status of epidemiologic and clinical research on radiation exposure in relation to risk of breast, thyroid cancer, and leukemia, cardiopulmonary events, and other late effects. Topics discussed included synergy between radiation exposure and genetic background; late effects of radiation therapy in childhood cancer survivors and several other medically exposed cohorts; leukemia risk seen in Russian and Chernobyl studies, and leukemia risk from computed tomography scans in childhood. This report summarizes the presentations at the meeting and discusses their significance in light of earlier studies and of other ongoing research.

  13. Radiation and noise exposures elicit biological and behavioural effects in the rat

    International Nuclear Information System (INIS)

    Trivedi, A.; Michaud, D.S.; Ferrarotto, C.; Keith, S.E.; Miller, S.M.; Bowers, W.J.; Kumarathsan, P.

    2003-01-01

    The presence of radiation and noise is ubiquitous in a living environment. Therefore, the effect of these sources alone and together on the body has the potential for public health consequences. We have examined the physiological and behavioural effects of separate and combined exposures to radiation and noise in adult male Sprague-Dawley rats. For three weeks animals were exposed to the following conditions: 1) daily exposure to x-rays (cumulative whole body dose = 5Gy); 2) random intermittent noise band-limited between 400Hz-20 kHz; 2 h/day 90 dB lin and 3) combined exposures. Control animals were housed under ambient noise conditions (∼ 55-60 dBA) and sham-exposed to x-rays. The mean body weight gain (initial avg. ∼ 250g) appeared to be affected by the treatments; control (88g); noise (76g); radiation (60g) and noise/radiation (43g). Compared to control and noise only animals, plasma levels of 8-hydroxy-2'-deoxyguanosine increased significantly in animals exposed to both radiation alone and radiation with noise, while big-endothelin-1 was significantly reduced in both groups exposed to radiation. There were no noticeable changes in the levels of adrenocorticotrophic hormone and the variability in plasma norepinephrine and epinephrine precluded conclusions with respect to changes in sympathetic activity. No groups showed any consistent changes in plasma levels of interleukin-1, corticotrophin releasing hormone or urocortin. Plasma corticosterone increased in animals exposed to only noise, but this hormone was significantly reduced in animals exposed to only radiation. Behavioural endpoints revealed that startle amplitude (105dB) was highest in animals exposed to only noise and lowest in animals exposed to both noise and radiation, compared to the control animals. These results suggest that radiation exposure might alter systems activated by stressor exposure and/or act independently to influence health outcomes

  14. More than a century of research of the biological effects of ionizing radiation; Mehr als ein Jahrhundert Forschung zu den biologischen Wirkungen ionisierender Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, W.U. [Universitaetsklinikum Essen (Germany). Inst. fuer Medizinische Strahlenbiologie

    2016-07-01

    Already shortly after the discovery of ionising radiation in 1895 it became obvious, that this type of radiation is able to cause severe health effects. In the beginning, deterministic effects were observed, like hair loss and skin burns and somewhat later stochastic effects like leukaemia and skin tumours. Soon studies started why this happens; not only because of protection against the harmful effects of ionising radiation, but also against the background of the therapeutic application of this type of radiation. The studies were initially done in animal experiments, subsequently experiments on the cellular and chromosomal level dominated, until research turned to the molecular level. It is increasingly obvious that the complete organism should be considered, because the complex interactions in the organism are not reflected on the molecular or the cellular level. In the remote future, even the inclusion of the total ecosphere may be necessary for risk considerations.

  15. Metformin: A Novel Biological Modifier of Tumor Response to Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Koritzinsky, Marianne, E-mail: mkoritzi@uhnresearch.ca

    2015-10-01

    Over the last decade, evidence has emerged to support a role for the antidiabetic drug metformin in the prevention and treatment of cancer. In particular, recent studies demonstrate that metformin enhances tumor response to radiation in experimental models, and retrospective analyses have shown that diabetic cancer patients treated with radiation therapy have improved outcomes if they take metformin to control their diabetes. Metformin may therefore be of utility for nondiabetic cancer patients treated with radiation therapy. The purpose of this review is to examine the data pertaining to an interaction between metformin and radiation, highlighting the essential steps needed to advance our current knowledge. There is also a focus on key biomarkers that should accompany prospective clinical trials in which metformin is being examined as a modifying agent with radiation therapy. Existing evidence supports that the mechanism underlying the ability of metformin to enhance radiation response is multifaceted, and includes direct radiosensitization as well as a reduction in tumor stem cell fraction, proliferation, and tumor hypoxia. Interestingly, metformin may enhance radiation response specifically in certain genetic backgrounds, such as in cells with loss of the tumor suppressors p53 and LKB1, giving rise to a therapeutic ratio and potential predictive biomarkers.

  16. physical, chemical, technological and biological properties of some mutant oil seeds induced by gamma radiation

    International Nuclear Information System (INIS)

    Ali, H.G.M.

    2003-01-01

    The present study has been undertaken to evaluated sesame, sunflower and safflower seeds induced by gamma rays, as plant breeding unit, plant research department, radioisotope application division, nuclear research center, atomic energy authority Inshas. the obtained results indicate the following : chemical composition of mutant seeds: the radiation mutation caused a significant increase in both oil and ash content total carbohydrates showed a significant decreased in sesame seeds. radiation mutation induced significant increase in oil and protein content of sunflower and safflower seeds. while the total carbohydrate showed a significant decrease. physiochemical properties of oils extracted mutant seeds: the radiation mutation had no real effect on the refractive index and A.V of oils extracted from control and mutant sesame, sunflower and safflower seeds. while it caused a slight increase in red color and P.V. of sesame oil, the thiobarbituric acid (TBA) value of mutant sesame oil was not alter upon radiation mutation, but it induced a slight decrease in TBA of mutant sunflower and safflower oils. the unsaponifiable matter percentage of oils extracted from mutant sesame, sunflower and safflower seeds were slightly increased by radiation mutation .radiation mutation of seeds had no real effect on the total SFA and USFA of sesame oil. however, radiation mutation induced a remarkable changes in fatty acid profiles of sunflower and safflower oil as total SFA decreased, while USFA increased. Uric acid was only detected in oil extracted from mutant sunflower seeds

  17. Paradigm Shift in Radiation Biology/Radiation Oncology-Exploitation of the "H₂O₂ Effect" for Radiotherapy Using Low-LET (Linear Energy Transfer) Radiation such as X-rays and High-Energy Electrons.

    Science.gov (United States)

    Ogawa, Yasuhiro

    2016-02-25

    Most radiation biologists/radiation oncologists have long accepted the concept that the biologic effects of radiation principally involve damage to deoxyribonucleic acid (DNA), which is the critical target, as described in "Radiobiology for the Radiologist", by E.J. Hall and A.J. Giaccia [1]. Although the concepts of direct and indirect effects of radiation are fully applicable to low-LET (linear energy transfer) radioresistant tumor cells/normal tissues such as osteosarcoma cells and chondrocytes, it is believed that radiation-associated damage to DNA does not play a major role in the mechanism of cell death in low-LET radiosensitive tumors/normal tissues such as malignant lymphoma cells and lymphocytes. Hall and Giaccia describe lymphocytes as very radiosensitive, based largely on apoptosis subsequent to irradiation. As described in this review, apoptosis of lymphocytes and lymphoma cells is actually induced by the "hydrogen peroxide (H₂O₂) effect", which I propose in this review article for the first time. The mechanism of lymphocyte death via the H₂O₂ effect represents an ideal model to develop the enhancement method of radiosensitivity for radiation therapy of malignant neoplasms. In terms of imitating the high radiosensitivity of lymphocytes, osteosarcoma cells (representative of low-LET radioresistant cells) might be the ideal model for indicating the conversion of cells from radioresistant to radiosensitive utilizing the H₂O₂ effect. External beam radiation such as X-rays and high-energy electrons for use in modern radiotherapy are generally produced using a linear accelerator. We theorized that when tumors are irradiated in the presence of H₂O₂, the activities of anti-oxidative enzymes such as peroxidases and catalase are blocked and oxygen molecules are produced at the same time via the H₂O₂ effect, resulting in oxidative damage to low-LET radioresistant tumor cells, thereby rendering them highly sensitive to irradiation. In this

  18. Paradigm Shift in Radiation Biology/Radiation Oncology—Exploitation of the “H2O2 Effect” for Radiotherapy Using Low-LET (Linear Energy Transfer Radiation such as X-rays and High-Energy Electrons

    Directory of Open Access Journals (Sweden)

    Yasuhiro Ogawa

    2016-02-01

    Full Text Available Most radiation biologists/radiation oncologists have long accepted the concept that the biologic effects of radiation principally involve damage to deoxyribonucleic acid (DNA, which is the critical target, as described in “Radiobiology for the Radiologist”, by E.J. Hall and A.J. Giaccia [1]. Although the concepts of direct and indirect effects of radiation are fully applicable to low-LET (linear energy transfer radioresistant tumor cells/normal tissues such as osteosarcoma cells and chondrocytes, it is believed that radiation-associated damage to DNA does not play a major role in the mechanism of cell death in low-LET radiosensitive tumors/normal tissues such as malignant lymphoma cells and lymphocytes. Hall and Giaccia describe lymphocytes as very radiosensitive, based largely on apoptosis subsequent to irradiation. As described in this review, apoptosis of lymphocytes and lymphoma cells is actually induced by the “hydrogen peroxide (H2O2 effect”, which I propose in this review article for the first time. The mechanism of lymphocyte death via the H2O2 effect represents an ideal model to develop the enhancement method of radiosensitivity for radiation therapy of malignant neoplasms. In terms of imitating the high radiosensitivity of lymphocytes, osteosarcoma cells (representative of low-LET radioresistant cells might be the ideal model for indicating the conversion of cells from radioresistant to radiosensitive utilizing the H2O2 effect. External beam radiation such as X-rays and high-energy electrons for use in modern radiotherapy are generally produced using a linear accelerator. We theorized that when tumors are irradiated in the presence of H2O2, the activities of anti-oxidative enzymes such as peroxidases and catalase are blocked and oxygen molecules are produced at the same time via the H2O2 effect, resulting in oxidative damage to low-LET radioresistant tumor cells, thereby rendering them highly sensitive to irradiation. In this

  19. Review of the controversy on risks from low levels of radiation

    International Nuclear Information System (INIS)

    Higson, D.

    2001-01-01

    The need for regulation of low levels of radiation exposure, and the estimation of risks from such exposures, are based on the assumption that risk is proportional to dose without a threshold, the 'linear no-threshold (LNT) hypothesis'. This assumption is not supported by scientific data. There is no clear evidence of harm from low levels of exposure, up to at least 20 mSv (acute dose) or total dose rates of at least 50 mSv per year. Even allowing for reasonable extrapolation from radiation levels at which harmful effects have been observed, the LNT assumption should not be used to estimate risks from doses less than 100 mSv. Laboratory and epidemiological evidence, and evolutionary expectations of biological effects from low level radiation, suggest that beneficial health effects (sometimes called 'radiation hormesis') are at least as likely as harmful effects from such exposures. Controversy on this matter strikes at the basis of radiation protection practice

  20. Modification of primary radiation injuries of biological systems by into compounds

    International Nuclear Information System (INIS)

    Kuropteva, Z.V.; Shprints, Kh.; Zhumbaeva, T.T.; Kudryavtsev, M.E.

    1990-01-01

    The presebted results revealed that nitrocompounds decreased level of primary radiation injuries of biomacromolecules. Different mechanisms of radiosensitization with nitrocompounds were supposed to occur. A mechanism was suggested in which the main factor in radiosensitizing effect turned out to be radiation-induced formation of intermediate products of incomplete reduction of nitro group. They intensify radiation cytogentic effect on the tumor. The products were shown to occur in further reduction of anion-radical nitrocompounds in tissues under irradiation. 9 refs.; 7 figs.; 1 tab

  1. Cardiovascular diseases induced by low level ionizing radiation. Current status and proposal of future directions of the biological studies

    International Nuclear Information System (INIS)

    Iwasaki, Toshiyasu; Nomura, Takaharu; Ishii, Keiichiro

    2013-01-01

    In the publication on tissue reactions of the International Commission on Radiological Protection (ICRP), the risk of cardiovascular diseases (CVD) was calculated based on linear non-threshold model, without taking account of dose-rate effect. To evaluate the validity of this estimation, we analyzed recent epidemiological and biological findings on CVD at low dose or low dose-rate. Though epidemiological data suggested that radiation would have a causal association with CVD by inducing atherosclerosis, it was limited by heterogeneity among studies, and the contribution of other pathways was also suggested. As biological mechanisms, inflammation is considered as the critical factor of radiation induced CVD. However, the inflammatory responses at low dose were inconsistent among studies, and there were few data at low dose-rate. Furthermore, because those responses were transient, it was very difficult to link them to CVD with long latency. We proposed a concept for the analysis of these long latency diseases by focusing the premonitory symptoms of CVD which could be affected by radiation. As the premonitory symptoms recruitment of white blood cells to inflamed blood vessels and/or tissues would have the highest priority to investigate. To elucidate the dose-rate effect and reflect the results on the radiological protection, it would be important to examine the premonitory symptoms after long term exposure mimicking the actual situation, such as chronic exposure or fractionated exposure of very small dose. (author)

  2. Measurement of Relative Biological Effectiveness (RBE) for the Radiation Beam from Neutron Source Reactor YAYOI -Comparisons with Cyclotron Neutron and 60Co Gamma Ray-

    OpenAIRE

    HIROAKI, WAKABAYASHI; SHOZO, SUZUKI; AKIRA, ITO; Nuclear Engineering Research Laboratory, Faculty of Engineering, the University of Tokyo; Institute of Medical Science, the University of Tokyo; Institute of Medical Science, the University of Tokyo

    1983-01-01

    Radiation biology and/or therapy research and development for a research reactor beam need specific RBEs of neutrons as well as of specific reactions. RBEs for reactor beams measured in situ condition are interesting because actual radiation effects on each biological system are different depending on detailed conditions of irradiation. A small powered research reactor (Fast Neutron Source Reactor: YAYOI) was examined here as a neutron beam source for obtaining survival curves in a manner usu...

  3. NOTE: Implementation of biologically conformal radiation therapy (BCRT) in an algorithmic segmentation-based inverse planning approach

    Science.gov (United States)

    Vanderstraeten, Barbara; DeGersem, Werner; Duthoy, Wim; DeNeve, Wilfried; Thierens, Hubert

    2006-08-01

    The development of new biological imaging technologies offers the opportunity to further individualize radiotherapy. Biologically conformal radiation therapy (BCRT) implies the use of the spatial distribution of one or more radiobiological parameters to guide the IMRT dose prescription. Our aim was to implement BCRT in an algorithmic segmentation-based planning approach. A biology-based segmentation tool was developed to generate initial beam segments that reflect the biological signal intensity pattern. The weights and shapes of the initial segments are optimized by means of an objective function that minimizes the root mean square deviation between the actual and intended dose values within the PTV. As proof of principle, [18F]FDG-PET-guided BCRT plans for two different levels of dose escalation were created for an oropharyngeal cancer patient. Both plans proved to be dosimetrically feasible without violating the planning constraints for the expanded spinal cord and the contralateral parotid gland as organs at risk. The obtained biological conformity was better for the first (2.5 Gy per fraction) than for the second (3 Gy per fraction) dose escalation level.

  4. The use of apoptosis in human lymphocytes peripheral as alternative methods in biological dosimetry of radiation effects from cobalt-60

    International Nuclear Information System (INIS)

    Lemes, Marisa

    1997-01-01

    Gamma rays affect cells in dose-response manner, resulting in cell death, as in cancer radiotherapy. The ionizing radiation acts by transferring energy, mainly by free radicals from water radiolysis that result in nucleic acid damage and other effects in lipids and proteins, The level of exposure is indirectly estimated by physical dosimetry, but the biological dosimetry can measure the direct radiation effect, mainly in post-dividing cells by classical cytogenetic approach. Recently, it was reported that irradiated cells develop an induced programmed death or apoptosis. With a biological dosimetric technique, we measured apoptotic cell fraction in 60 Co in vitro irradiated blood cells from voluntary healthy donors. The agarose gel electrophoresis showed a low sensitivity, because cell DNA presented the characteristic pattern only when the cells were exposed to 100 c Gy or more. Using a terminal DNA labeling technique we observed that the apoptotic cell fraction proportionally increases with irradiation. Similar sensitivity was observed when compared to classical cytogenetics (3 c Gy minimum detection level). These techniques are easier to perform, do not need cell culture and all cells, including interphase ones, can be analyzed, providing a good tool in biological dosimetry. (author)

  5. Biological effects of low doses of radiation at low dose rate

    International Nuclear Information System (INIS)

    1996-05-01

    The purpose of this report was to examine available scientific data and models relevant to the hypothesis that induction of genetic changes and cancers by low doses of ionizing radiation at low dose rate is a stochastic process with no threshold or apparent threshold. Assessment of the effects of higher doses of radiation is based on a wealth of data from both humans and other organisms. 234 refs., 26 figs., 14 tabs

  6. Are biological effects of space radiation really altered under the microgravity environment?

    Science.gov (United States)

    Yatagai, Fumio; Ishioka, Noriaki

    2014-10-01

    Two major factors of space environment are space radiation and microgravity. It is generally considered that a high level of ionizing radiation (IR) in space has an influence on living organisms including humans; therefore, the possible alteration of space-radiation influences by the microgravity environment is of great concern. In fact, examination of such a possibility has been extensively conducted since the early days of space experiments, suggesting a possible synergistic effect of radiation and microgravity in some experiments but a negative observation in others. Because these complicated results remain not well understood, we propose a solution to this problem. Gene expression analysis is one of the solutions to the problem. In fact, gene expression may be changed by microgravity, and further modification may be possible through IR. This result could reveal an interactive effect of both factors on the cellular responses, which could in turn reveal whether the human-health abnormalities expected under the microgravity environment can be altered by space radiation. We believe that this is a new aspect in the study of the interactive effect of radiation and microgravity. However, further improvements in space experimental technologies are required for future studies.

  7. Biological effects of neutron radiation and their implications for the nuclear power industry

    International Nuclear Information System (INIS)

    Dennis, J.A.

    1983-01-01

    Stimulated biophysical theories of the action of radiation on the cells of mammalian tissues, research on the effects of neutrons has been interpreted as implying that neutron radiation is about 60 times more effective than gamma radiation for the induction of tumours in rodents and for shortening their lives. This contrasts with the assumption made for protection purposes that it is only about ten times as effective. However, the same experiments can be interpreted also as implying that gamma radiation at the dose rates encountered in the workplace is five to ten times less effective than is generally assumed. Taken together these observations suggest that the real risks to humans from neutrons are comparable with the assumed risks from X- and gamma radiation. Further data are required to confirm these observations and their interpretation, and in the short term there is no need to change the current practices of radiological protection as regards neutron radiation. Nevertheless, it might be wise for long-term planning purposes to anticipate a reduction in the maximum permissible fluences of neutrons by a factor of about 3. (author)

  8. Manhattan transfer: lethal radiation, bone marrow transplantation, and the birth of stem cell biology, ca. 1942-1961.

    Science.gov (United States)

    Kraft, Alison

    2009-01-01

    This study investigates how, in the late 1940s and 1950s, fears of nuclear accidents and nuclear warfare shaped postwar radiobiology. The new and intense forms of radiation generated by nuclear reactor technology, and which would be released in the event of a nuclear war, created concerns about a public-health hazard unprecedented in form and scale. Fears of inadvertent exposure to acute and potentially lethal radiation launched a search for anti-radiation therapies, out of which emerged the new technique of bone marrow transplantation (BMT). This study analyzes the use of BMT first as a research tool to explore the biological effects of ionizing radiation, and then as an adjunct to radiotherapy for the treatment of cancer. In highlighting how BMT became the province of different research and clinical constituencies, this study develops an understanding of the forces and contingencies that shaped its development. Exploring the emergence of BMT and the uses to which it was put, it reveals that BMT remained a technique in the making -- unstable and far from standardized, even as it became both a widely used research tool and rapidly made its way into the clinic. More broadly, it casts new light on one route through which the Manhattan Project influenced postwar radiobiology; it also affords new insights into one means by which radiobiology came to serve the interests of the Cold War state. In its focus on BMT this paper provides a new perspective on the evolving relationship between radiobiology and biomedicine in the postwar period.

  9. Prostate radiation in non-metastatic castrate refractory prostate cancer provides an interesting insight into biology of prostate cancer

    Directory of Open Access Journals (Sweden)

    Pascoe Abigail C

    2012-03-01

    Full Text Available Abstract Background The natural history of non-metastatic castrate refractory prostate cancer is unknown and treatment options are limited. We present a retrospective review of 13 patients with locally advanced or high risk prostate cancer, initially treated with hormone monotherapy and then treated with prostate radiation after becoming castration refractory. Findings Median PSA response following prostate radiation was 67.4%. Median time to biochemical progression following radiotherapy was 15 months and to detection of metastatic disease was 18.5 months. Median survival from castration resistance (to date of death or November 2011 was 60 months, with median survival from RT 42 months. Conclusion Prostate radiation appears to be beneficial even in patients with potential micrometastatic disease, which supports the hypothesis that the primary tumour is important in the progression of prostate cancer. These results are an interesting addition to the literature on the biology of prostate cancer especially as this data is unlikely to be available in the future due to combined prostate radiation and androgen deprivation therapy now being the standard of care.

  10. Geant4-DNA simulation of DNA damage caused by direct and indirect radiation effects and comparison with biological data.

    Science.gov (United States)

    Villagrasa, Carmen; Meylan, Sylvain; Gonon, Geraldine; Gruel, Gaëtan; Giesen, Ulrich; Bueno, Marta; Rabus, Hans

    2017-09-01

    In this work we present results obtained in the frame of the BioQuaRT project. The objective of the study was the correlation between the number of radiation-induced double strand breaks (DSB) of the DNA molecule and the probability of detecting nuclear foci after targeted microbeam irradiation of cells with protons and alpha particles of different LET. The former were obtained by simulation with new methods integrated into Geant4-DNA that permit calculating the number of DSB in a DNA target model induced by direct and indirect radiation effects. A particular focus was laid in this work on evaluating the influence of different criteria applied to the simulated results for predicting the formation of a direct SSB. Indeed, these criteria have an important impact on the predicted number of DSB per particle track and its dependence with LET. Among the criteria tested in this work, the case that a direct radiation interaction leads to a strand break if the cumulative energy deposited in the backbone part of one nucleotide exceeds a threshold of 17.5 eV leads to the best agreement with the relative LET dependence of number of radiation induced foci. Further calculations and experimental data are nevertheless needed in order to fix the simulation parameters and to help interpreting the biological experimental data observed by immunofluorescence in terms of the DSB complexity.

  11. The combined effect of gamma radiation and heat on some biological aspects of onion bulb fly Eumerus amoenus Loew

    International Nuclear Information System (INIS)

    El-Orabi, M.N.; Gharieb, O.H.; Hamza, A.F.H.; El-Saeadi, A.A.; Hussain, A.E.

    2010-01-01

    The effect of sub-sterilizing doses of gamma radiation, in combination with three degrees of temperature (20, 25 and 30 degree C). on some biological parameters of Eumerus Amoenus Loew were studied. The combined effect of radiation and heat were carried out on developmental stages namely; larval, pupal stages. Larval duration decreased significantly by increasing rearing temperature and increased by raising heat regardless larval instar. The same trend was observed in percent pupation, percent emergence. Irradiation of larvae decreases the adult emergence percentage under all temperatures. The results indicate that no adult male emergence when irradiated 4-d-old larvae at all doses when kept at 20 and 25 degree C. life-span of adults emerged from pupae irradiated as 5 and 7 day-old with sterilizing and sub-sterilizing doses was affected depending upon the dose level, temperatures and age of pupae at the time of irradiation. Fecundity of a female decreased by decreasing temperature degree or increasing radiation dose. Also, fertility of males decreased by radiation dose and by mating to irradiated females, this decrease was increased by increasing age of male and by decreasing temperature

  12. Breeding biology of tree swallows and house wrens in a gradient of gamma radiation

    International Nuclear Information System (INIS)

    Zach, R.; Mayoh, K.R.

    1982-01-01

    In a gradient of gamma radiation ranging from 38.7 mC.kg -1 .d -1 to background levels of 0.05 μC.kg -1 .d -1 , Tree Swallows (Iridoprocne bicolor) and House Wrens (Troglodytes aedon) avoided nesting in areas of high radiation. Nest boxes selected by swallows and wrens had a mean exposure rate of only 9.3 and 6.6 μC.kg -1 .d -1 , respectively. Lateral and canopy vegetation indices and nest hole height and direction could not explain the observed pattern of box selection. Of the boxes with low exposure rates, swallows selected those with little vegetation cover, whereas wrens chose boxes with heavy cover. It appears that the birds responded to radiaton levels as low as 100 times background but it is not clear whether they actually detected radiation or simply responded to secondary clues. The number of swallows and wrens fledged per box was unrelated to radiation exposure. The same was true for number of eggs, hatching success, fledging success, incubation time, and nestling time. Breeding success was reduced because of infertile eggs, eggs with dead embryos, cracked eggs, predation, adverse weather, abandonment, and parasites. The logistic model was ideally suited for describing gains in mass in nestling swallows and wrens. Growth of nestlings was not related to radiation exposure as indicated by the growth rate constant, asymptotic mass, and the proportion of variation explained by the logistic model. The data show that birds avoided adverse effects of radiation by judicious box selection. However, there were indications that at higher breeding densities birds may use high-exposure boxes, where breeding success or growth of nestlings may become reduced due to radiation

  13. Breeding biology of Tree Swallows and House Wrens in a gradient of gamma radiation

    International Nuclear Information System (INIS)

    Zach, R.; Mayoh, K.R.

    1982-01-01

    In a gradient of gamma radiation from 38.7 mC kg - 1 .d - 1 to background levels of 0.05 μC. kg - 1 . d - 1 to background levels of 0.05 μC . kg - 1 . d - 1 , Tree Swallows (Iridoprocne bicolor) and House Wrens (Troglodytes aedon) avoided nesting in areas of high radiation. Nest boxes selected by swallows and wrens had a mean exposure rate of only 9.3 and 6.6 μC . kg - 1 . d - 1 , respectively. Lateral and canopy vegetation indices and nest hole height and direction could not explain the observed pattern of box selection. Of the boxes with low exposure rates, swallows selected those with little vegetation cover, whereas wrens chose boxes and heavy cover. It appears that the birds responded to radiation levels as low as 100 times background, but it is not clear whether they actually detected radiation or simply responded to secondary clues. The number of swallows and wrens fledged per box was unrelated to radiation exposure. The same was true for number of eggs, hatching success, fledging success, incubation time, and nestling time. Breeding success was reduced because of infertile eggs, eggs with dead embryos, cracked eggs, predation, adverse weather, abandonment, and parasites. The logistic model was ideally suited for describing gains in mass in nestling swallows and wrens. Growth of nestlings was not related to radiation exposure as indicated by the growth rate constant, asymptotic mass, and the proportion of variation explained by the logistic model. Breeding and growth performance were similar in studies not involving experimental radiation

  14. [What is self-harm?].

    Science.gov (United States)

    Sommerfeldt, Bente; Skårderud, Finn

    2009-04-16

    The aim with this article is to provide an introduction to self-harm as a clinical phenomenon, with phenomenological descriptions and definitions, and by presenting risk factors, epidemiological data and functions of self-harm. The basis for the article is a non-systematic literature search of the electronic databases Medline, PsychInfo and EMBASE (1985 - 2008). and our own archive of literature on self-harm. There is some evidence for an increase in the prevalence of self-harm. Among possible risk factors are childhood abuse, abandonment, neglect, trauma and separation, and the affective quality of the attachment bonds in childhood. A common factor is self-harm as a bodily practice for affect regulation, and as such, it can be understood as a dysfunctional competence. To search for understanding of self-harm in individual, familiar and cultural contexts contributes to meet individuals with such tendencies with empathy and beneficial interventions.

  15. Radiation protection

    International Nuclear Information System (INIS)

    Ures Pantazi, M.

    1994-01-01

    This work define procedures and controls about ionizing radiations. Between some definitions it found the following topics: radiation dose, risk, biological effects, international radioprotection bodies, workers exposure, accidental exposure, emergencies and radiation protection

  16. Biological effects of low-level ionizing and non-ionizing radiation

    International Nuclear Information System (INIS)

    Upton, A.C.

    1986-01-01

    Early in this century it was recognized that large doses of ionizing radiation could injure almost any tissue in the body, but small doses were generally thought to be harmless. By the middle of the century however it came to be suspected that even the smallest doses of ionizing radiation to the gonads might increase the risk of hereditary disease in subsequently-conceived offspring. Since then the hypothesis that carcinogenic and teratogenic effects also have no threshold has been adopted for purposes of radiological protection. It is estimated nevertheless that the risks that may be associated with natural background levels of ionizing irradiation are too small to be detectable. Hence validation of such risk estimates will depend on further elucidation of the dose-effect relationships and mechanisms of the effects in question, through studies at higher dose levels. In contrast to the situation with ionizing radiation, exposure to natural background levels of ultraviolet radiation has been implicated definitively in the etiology of skin cancers in fair-skinned individuals. Persons with inherited effects in DNA repair capacity are particularly susceptible. Non-ionizing radiations of other types can also affect health at high dose levels, but whether they can cause injury at low levels of exposure is not known

  17. Evaluation of the protective and curative role of curcumin and venoruton against biological effects of radiation

    International Nuclear Information System (INIS)

    El-Sayed, N.M.

    2006-01-01

    Curcumin (diferuloyl methane) and venoruton [O-(beta-hydroxyethyl)-rutosides] are powerful antioxidants and are important in protecting the cells from damage. The present study aims to evaluate the role of curcumin alone and curcumin with venoruton on radiation-induced changes in male rats exposed to a dose of 5 Gy gamma irradiation. Experimental analyses were performed 1, 7 and 14 days post-irradiation in all animal groups. Exposure to ionizing radiation resulted in decrease in glutathione content and SOD, G6PD and CPK activities and increase in lactate dehydrogenase and GOT activities and creatinine level. The results obtained showed that treatment of rats with olive oil pre and post-irradiation has significantly minimized radiation-induced changes. Curcumin dissolved in olive oil pre and post-irradiation significantly improved the radiation-induced changes while administration of venoruton with curcumin in olive oil provided a better amelioration. It could be concluded that, curcumin in olive oil plus venoruton showed an obvious protective and curative role against the hazards of gamma radiation in male rats

  18. Cytogenetic techniques for biological indications and dosimetry of of radiation damages in humans

    International Nuclear Information System (INIS)

    Hadjidekova, V.

    2003-01-01