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Transmission scanning II

Description: From nuclear science symposium; San Francisco, California, USA (14 Nov 1973). Work has been continued on the development of techniques for imaging spatial elemental distributions by means of differential absorption about the K- absorption edge of the particular element Z. A method to correct for spurious effects due to differential absorption in overlying absorber is described. Initial clinical studies of thyroid iodine images on patierts are presented. Application of absorption edge transmission scanning to measurements of Ca cortent in thin in-vitro samples of rat bone is also discussed. An x-ray source with a broad energy spectrum was used. (CH)
Date: January 1, 1973
Creator: Alberi, J.L.; Kraner, H.W.; Bradley-Moore, P. & Atkins, H.L.
Partner: UNT Libraries Government Documents Department

Natural iodine and iodine-129 in mammalian thyroids and environmental samples taken from locations in the United States

Description: From symposium on enviromnental surveillance around nuclear installation; Warsaw, Poland (5 Nov 1973). Bovine and other mammalian thyroids, air, precipitation, water, grass, and milk samples from selected locations were analyzed for their natural iodine and iodine-129 content. Particle filters and activated charcoal beds were used to collect the particulate and gaseous iodine fractions from the air. Anion exchange was used for the separation of iodine from liquid samples. Cumbustion methods were used for iodine separation from solid samples, anlon exchange resins, and air filters. Iodine-129 and natural iodine concentrations were determined by neutron activation analysis with a detection limit of about 10/sup 8/ atoms of iodine-129 per sample. Analytical results of both /sup 129/I concentrations and ratios of atoms of /sup 129/I per atom of /sup 127/I for these samples are summarized. The small radiation doses to human thyroids projected from these low /sup 129/I concentrations are also discussed. (auth)
Date: January 1, 1973
Creator: Brauer, F.P.; Soldat, J.K.; Tenny, H. & Strebin, R.S. Jr.
Partner: UNT Libraries Government Documents Department

Medical status of Marshallese accidentally exposed to 1954 Bravo fallout radiation: January 1988 through December 1991

Description: The purpose of this report is to disseminate information concerning the medical status of 253 Marshallese exposed to fallout radiation in 1954. This report discusses the medical care provided and the medical findings for the years 1988-1991. Details of the BRAVO thermonuclear accident that caused the exposure have been published, and a 1955 article in the Journal of the American Medical Association describing the acute medical effects in the exposed population remains a definitive and relevant description of events. Participation in the Marshall Islands Medical Program by the exposed Marshallese is voluntary. In the spring and fall of each year, medical surveillance is provided to exposed and unexposed cohorts. Examinations performed include: a cancer-related examination as defined by the American Society, an annual thyroid examination and thyroid function testing, serum prolactin testing looking for pituitary tumors, annual blood counts to include platelets, and evaluation for paraneoplastic evidence of neoplasms. This report details the medical program, medical findings, and thyroid surgery findings. Deaths (4 exposed and 10 nonexposed) that occurred during the reporting period are discussed. There is a mild but relatively consistent depression of neutrophil, lymphocyte, and platelet concentrations in the blood of the exposed population. This depression appears to be of no clinical significance. Thyroid hypofunction, either clinical or biochemical, has been documented as a consequence of radiation exposure in 14 exposed individuals. Previously, one other exposed person was diagnosed with basal cell carcinoma. During this reporting period, a thyroid nodule was identified in an individual who was in utero during the exposure. Upon pathologic review, the nodule was diagnosed as occult papillary carcinoma.
Date: July 1, 1995
Creator: Howard, J.E.; Heotis, P.M.; Scott, W.A. & Adams, W.H.
Partner: UNT Libraries Government Documents Department

Estimated long term health effects of the Chernobyl accident

Description: Apart from the dramatic increase in thyroid cancer in those exposed as children, there is no evidence to date of a major public health impact as a result of radiation exposure due to the Chernobyl accident in the three most affected countries (Belarus, Russia, and Ukraine). Although some increases in the frequency of cancer in exposed populations have been reported ,these results are difficult to interpret, mainly because of differences in the intensity and method of follow-up between exposed populations and the general population with which they are compared. If the experience of the survivors of the atomic bombing of Japan and of other exposed populations is applicable, the major radiological impact of the accident will be cases of cancer. The total lifetime numbers of excess cancers will be greatest among the `liquidators` (emergency and recovery workers) and among the residents of `contaminated` territories, of the order of 2000 to 2500 among each group (the size of the exposed populations is 200,000 liquidators and 3,700,000 residents of `contaminated` areas). These increases would be difficult to detect epidemiologically against an expected background number of 41500 and 433000 cases of cancer respectively among the two groups. The exposures for populations due to the Chernobyl accident are different in type and pattern from those of the survivors of the atomic bombing of Japan. Thus predictions derived from studies of these populations are uncertain. The extent of the incidence of thyroid cancer was not envisaged. Since only ten years have lapsed since the accident, continued monitoring of the health of the population is essential to assess the public health impact.
Date: July 1, 1996
Creator: Cardis, E.
Partner: UNT Libraries Government Documents Department

Estimated long-term health effects

Description: Apart from the dramatic increase in thyroid cancer in those exposed as children, there is no evidence to date of a major public health impact of the radiation exposure from the Chernobyl accident in the three most affected countries. Although some increases in the frequency of cancer in exposed populations have been reported, these results are difficult to interpret, mainly because of differences in the intensity and method of follow-up between exposed populations and the general population to which they are compared. If the experience of atomic bomb survivors and of other exposed populations is applicable, the major radiological impact of the accident will be cancer and the total lifetime numbers of excess cancers will be greatest among the liquidators and among the residents of contaminated territories, of the order of 2,000 to 2,500. These increases would be difficult to detect epidemiologically against an expected background number of 41,500 and 433,000 respectively (size of the exposed populations: 200,000 and 3,700,000, respectively). It is noted, however, that the exposures received by populations exposed as a result of Chernobyl are different (in type and pattern) from those of atomic bomb survivors. Predictions derived from these populations are therefore uncertain. Indeed, the extent of the increase in thyroid cancer incidence in persons exposed as children was not foreseen. In addition, only ten years have passed since the accident. It is essential therefore that monitoring of the health of the population be continued in order to assess the public health impact of the accident, even if, apart from leukemia among liquidators, little detectable increase of cancers due to radiation from the Chernobyl accident is expected.
Date: April 1, 1996
Creator: Cardis, F.; Okeanov, A.E.; Likthariev, I.; Prisyazhniuk; Anspaugh, L.R.; Mabuchi, K. et al.
Partner: UNT Libraries Government Documents Department

Iodine-129 Dose in LLW Disposal Facility Performance Assessments

Description: Iodine-129 has the lowest Performance Assessment derived inventory limit in SRS disposal facilities. Because iodine is concentrated in the body to one organ, the thyroid, it has been thought that dilution with stable iodine would reduce the dose effects of 129I.Examination of the dose model used to establish the Dose conversion factor for 129I shows that, at the levels considered in performance assessments of low-level waste disposal facilities, the calculated 129I dose already accounts for ingestion of stable iodine. At higher than normal iodine ingestion rates, the uptake of iodine by the thyroid itself decrease, which effectively cancels out the isotopic dilution effect.
Date: October 15, 1999
Creator: Wilhite, E.L.
Partner: UNT Libraries Government Documents Department

Reconstruction of thyroid doses for the population of Belarus following the Chernobyl accident

Description: As a sequela to the large release of {sup 131}I from the accident at the Chernobyl Nuclear Power Plant, an expected late effect is thyroid cancer, especially in children. In anticipation of this problem, hundreds of thousands of measurements of thyroid glands were made with survey meters. Much attention was also focused on measuring the deposition density of {sup 137}Cs. The expectation was that the latter measurement could be a good surrogate for the deposition density of {sup 131}I, so that ecological models could be used to reconstruct thyroid doses in locations where no direct measurements of thyroid activity were made. However, this assumption has been seriously questioned, and there is interest in a more suitable surrogate that can still be measured even nine years or more after the accident. The purpose of this paper is to discuss the reconstruction of thyroid doses for a case-control study of childhood-thyroid cancer that has just been concluded, to discuss the reconstruction of thyroid doses for a current cohort study of childhood-thyroid cancer, and to discuss the use of {sup 129}I as a surrogate for the deposition density of {sup 131}I.
Date: September 1, 1995
Creator: Gavrilin, Y.I.; Khrouch, V.T.; Shinkarev, S.M.; Minenko, V.F.; Drozdovich, V.V.; Ulanovsky, A.V. et al.
Partner: UNT Libraries Government Documents Department

Environmental Analysis of Endocrine Disrupting Effects from Hydrocarbon Contaminants in the Ecosystem

Description: This annual report summarizes the progress of three years of a three-year grant awarded to the Center for Bioenvironmental Research (CBR) at Tulane and Xavier Universities. The objective of this project is to determine how environmental contaminants, namely hydrocarbons, can act as hormones or anti-hormones in different species present in aquatic ecosystems. The three major areas of research include (1) a biotechnology based screening system to identify potential hormone mimics and antagonists; (2) an animal screening system to identify biomarkers of endocrine effects; and (3) a literature review to identify compounds at various DOE sites that are potential endocrine disruptors. Species of particular focus in this study are those which can serve as sentinel species (e.g., amphibians) and, thus, provide early warning signals for more widespread impacts on an ecosystem and its wildlife and human inhabitants. The focus of the literature research was to provide an analysis of the contaminants located on or around various Department of Energy (DOE) sites that are or have the potential to function as endocrine disruptors and to correlate the need for studying endocrine disruptors to DOE's programmatic needs. Previous research within the Center for Bioenvironmental Research at Tulane and Xavier Universities has focused on understanding the effects of environmental agents on the human and wildlife health and disease. In particular this research has focused on how exogenous agents can function to mimic or disrupt normal endocrine signaling, i.e. estrogen, thyroid within various systems from whole animal studies with fish, amphibians and insects to human cancer cell lines. Significant work has focused on the estrogenic and anti-estrogenic action of both synthetic organochlorine chemicals and naturally produced phytochemicals. Recent projects have extended these research objectives to examination of these environmental agents on the symbiotic relationship between nitrogen fixing rhizobial bacteria and leguminous plants. This research will ...
Date: June 1, 2000
Creator: McLachlan, John A.
Partner: UNT Libraries Government Documents Department

Dose-projection considerations for emergency conditions at nuclear power plants

Description: The purpose of this report is to review the problems and issues associated with making environmental radiation-dose projections during emergencies at nuclear power plants. The review is divided into three areas: source-term development, characterization of atmospheric dispersion and selection of appropriate dispersion models, and development of dosimetry calculations for determining thyroid dose and whole-body dose for ground-level and elevated releases. A discussion of uncertainties associated with these areas is also provided.
Date: May 1, 1983
Creator: Stoetzel, G.A.; Ramsdell, J.V.; Poeton, R.W.; Powell, D.C. & Desrosiers, A.E.
Partner: UNT Libraries Government Documents Department

Radiogenic neoplasia in thyroid and mammary clonogens. Progress report, January 1, 1991--December 31, 1991

Description: We have developed rat thyroid and mammary clonogen transplantation systems for the study of radiogenic cancer induction at the target cell level in vivo. The epithelial cell populations of both glands contain small subpopulations of cells which are capable of giving rise to monoclonal glandular structures when transplanted and stimulated with appropriate hormones. During the end of the last grant year and the first half of the current grant year, we have completed analyses and summarized for publication: investigations on the relationship between grafted thyroid cell number and the rapidity and degree of reestablishment of the thyroid-hypothalamicpituitary axis in thyroidectomized rats maintained on a normal diet or an iodine deficient diet; studies of the persistence of, and the differentiation potential and functional characteristics of, the TSH- (thyrotropin-) responsive sub-population of clonogens during goitrogenesis, the plateau-phase of goiter growth, and goiter involution; studies of changes in the size of the clonogen sub-population during goitrogenesis, goiter involution and the response to goitrogen rechallenge; and the results of the large carcinogenesis experiment on the nature of the grafted thyroid cell number-dependent suppression of promotion/progression to neoplasia in grafts of radiation-initiated thyroid cells. We are testing new techniques for the culture, cytofluorescent analysis and characterization mammary epithelial cells and of clonogens in a parallel project, and plan to apply similar technology to the thyroid epithelial cells and clonogen population. Data from these studies will be used in the design of future carcinogenesis experiments on neoplastic initiation by high and low LET radiations and on cells interactions during the neoplastic process.
Date: May 31, 1991
Creator: Clifton, K. H.
Partner: UNT Libraries Government Documents Department

Radiogenic neoplasia in thyroid and mammary clonogens. Progress report, January 1, 1993--December 31, 1993

Description: The induction of cancer by ionizing radiation is a matter of great practical importance to the nuclear industry, to national defense, to radiological medicine and to the general public. It is increasingly apparent that carcinogenesis is one of the leading dose-limiting effects of radiation exposure (Co90). Quantitative information at the cellular level is essential to an understanding of the mechanisms of radiogenic neoplastic initiation and the stages of promotion and progression to overt neoplasia. We have developed two experimental models, the rat thyroid and rat mammary clonogen transplant systems, for the quantitative study of radiation carcinogenesis at the cellular level in vivo (C185). The most important steps taken or completed during the current grant year include: (a) demonstration of the high age-dependent radiosensitivity of prepubertal rat mammary clonogens to radiogenic damage which may influence their susceptibility to neoplastic initiation, and (b) demonstration of the feasibility of using a molecular test for clonogenicity in which Simple Sequence Repeats in the DNA serve as identifying signals of the genotypic origin of the cells. We have also (c) set up a large carcinogenesis experiment to test the effect of close intercellular contact in thyroid glands in situ on promotion-progression of radiogenically initiated clonogens, (d) achieved considerable further concentration of thyroid clonogens, and (e) begun to explore whether thyroid cells can be induced to give rise to three dimensional multicellular structures in culture in reconstituted basement membrane. These are discussed in this report.
Date: July 30, 1993
Creator: Clifton, K. H.
Partner: UNT Libraries Government Documents Department

Nuclear Medicine Program progress report for quarter ending September 30, 1992

Description: The radioiodination and in vivo evaluation of p-iodocaramiphen a muscarinic antagonist which binds with high affinity to the M{sub 1} receptor subtype in vitro are described. Biodistribution studies in female Fischer rats demonstrated that [{sup 125}I]-piodocaraminphen had significant cerebral localization, but the uptake did not demonstrate specific uptake in those cerebral regions rich in muscarinic receptors, and radioactivity washed out rapidly from the brain. In addition there was no significant blockage of activity when the rats were preinjected with quinuclidinyl benzilate. These results suggest that p-iodocaramiphen is not a good candidate for the in vivo study of M{sub 1} muscarinic receptor populations by SPECT. Because of the widespread interest and expected importance of the availability of large amounts of tungsten-188 required for the tungsten-188/rhenium-188 generator systems, we have investigated the large-scale production of tungsten-188 in the ORNL HFIR. We have also compared our production data with the theoretical production values and with experimental data available in the literature from other reactors. Tungsten-188 is produced in a fission nuclear reactor by double neutron capture of tungsten-186. The experimental yield of tungsten-188 is approximately 4 mCi/mg of tungsten-186 at the end of bombardment (EOB) in the HFIR operating at 85 MWt power for a one cycle irradiation ({approximately}21 days) at a thermal neutron flux of 2 {times} 10{sup 15} n.s{sup {minus}1}cm{sup {minus}2}.
Date: December 1, 1992
Creator: Knapp, F. F. Jr.; Ambrose, K. R.; Beets, A. L.; Callahan, A. P.; McPherson, D. W.; Mirzadeh, S. et al.
Partner: UNT Libraries Government Documents Department

Determination of dose distributions and parameter sensitivity. Hanford Environmental Dose Reconstruction Project; dose code recovery activities; Calculation 005

Description: A series of scoping calculations has been undertaken to evaluate the absolute and relative contribution of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford site. This scoping calculation (Calculation 005) examined the contributions of numerous parameters to the uncertainty distribution of doses calculated for environmental exposures and accumulation in foods. This study builds on the work initiated in the first scoping study of iodine in cow`s milk and the third scoping study, which added additional pathways. Addressed in this calculation were the contributions to thyroid dose of infants from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows` milk from Feeding Regime 1 as described in Calculation 001.
Date: December 1, 1992
Creator: Napier, B. A.; Farris, W. T. & Simpson, J. C.
Partner: UNT Libraries Government Documents Department

On the cells of origin of radiogenic thyroid cancer: New studies based on an old idea

Description: We have presented evidence that the functional thyroid follicles (follicular units, FU) which are formed in grafts of monodispersed rat thyroid cells, and hence the thyroid tumors which later develop in such grafts, are clonal in origin. Recent studies have been designed to investigate: whether cell number-dependent inhibition of promotion-progression is mediated by remote hormonal feed-back, local cell-cell interactions, or both; the cell population kinetics of the clonogen subpopulation during goitrogenesis and goiter involution; and the effect of prolonged exposure to high levels of TSH (thyrotropin) on the capacity of the clonogens to give rise to functional FU. The results indicate that local cell-cell interactions play an important role in the cell number-dependent suppression of neoplastic promotion-progression. They also show that if sufficient thyroid cells are grafted, the thyroid-pituitary axis can be reestablished in thyroidectomized rats fed normal diets. In such animals given iodine deficient diets, the FU that develop in the thyroid grafts shift their secretory pattern to increase the ratio of T3 (triiodothyronine) to T4 (thyroxine), and thus conserve the available iodine. Finally, the clonogenic subpopulation is conserved during both goitrogenesis and goiter involution. When they are transplanted to thyroidectomized recipients, clonogens from two types of goiters form FU that are morphologically indistinguishable from those that develop in grafts of normal thyroid clonogens. Furthermore, the secretion of T3 and T4 by such grafts is dependent on the grafted clonogen number, and hence FU formation, and not on the total number of thyroid cells transplanted. We conclude that the thyroid clonogens, the presumptive cancer progenitor cells, have many of the characteristics of stem cells.
Date: January 1, 1990
Creator: Clifton, K.H.; Domann, F.E. & Groch, K.M.
Partner: UNT Libraries Government Documents Department

Acute and long term health effects of radiation

Description: This paper covers selected aspects of the acute and long term health effects excluding acute radiation syndrome and carcinogenesis, resulting from exposure to ionizing radiation. The changes addressed in this paper are those witnessed within an organ or whole body rather than at the molecular or even cellular level. They include acute and late health effects. Some of these effects are threshold effects, meaning that the dose must exceed a certain threshold before one sees these effects. Less than the threshold dose results in no observable organ or whole body effect. The severity of the effects correlate directly with the amount of cell damage or cell death that has occurred. 15 refs., 4 figs., 8 tabs.
Date: November 19, 1986
Creator: Voelz, G.L.
Partner: UNT Libraries Government Documents Department

Twenty-year review of medical findings in a Marshallese population accidentally exposed to radioactive fallout

Description: A summary is presented of results of medical examinations of inhabitants of the Marshall Islands during the 20-year period following the exposure of Rongelap people to radioactive fallout in 1954. The initial effect observed was $beta$ burns of the skin of some individuals. Few significant findings were observed during the subsequent 9-year period, although an increase in miscarriages and stillbirths among the exposed women was noted. In 1963 some thyroid abnormalities and growth retardation of some children were noted. (177 references). (CH)
Date: January 1, 1975
Creator: Conard, R.A.
Partner: UNT Libraries Government Documents Department

Position Paper on Practicable Performance Criteria for the Removal Efficiency of Volatile Radionuclides

Description: As a result of fuel reprocessing, volatile radionuclides may be released from the facility stack if no processes are put in place to remove them. The radionuclides that are of concern in this document are 3H, 14C, 85Kr, and 129I. The question we attempted to answer is how efficient must this removal process be for each of these radionuclides? To answer this question, we examined the three regulations that may impact the degree to which these radionuclides must be reduced before process gases can be released from the facility. These regulations are 40 CFR 61 (EPA 2010a), 40 CFR 190(EPA 2010b), and 10 CFR 20 (NRC 2012). These regulations apply to the total radionuclide release and to a particular organ - the thyroid. Because these doses can be divided amongst all the radionuclides in different ways and even within the four radionuclides in question, we provided several cases. We first looked at the inventories for these radionuclides for three fuel types (PWR UOX, PWR MOX, and AHTGR), several burn-up values, and time out of reactor extending to 200 y. We calculated doses to the maximum exposed individual (MEI) with the EPA code CAP-88 (Rosnick 1992). Finally, we looked at two dose cases. Allocating all of the allowable dose to be used by the volatile radionuclides is one case, but, perhaps, unrealistic. In lieu of this, we arbitrarily selected a value of 10% of the allowable dose to be assigned to the volatile radionuclides. We calculated the required decontamination factors (DFs) for both of these cases, including the case for the thyroid dose for which 14C and 129I were the main contributors. With respect to 129I doses, we found that the highest dose was calculated with iodine as a fine particulate. The dose scaled as the fraction of the total 129I ...
Date: March 1, 2012
Creator: Jubin, R. T.; Soelberg, N. & Strachan, D. M.
Partner: UNT Libraries Government Documents Department

Chromosomal Rainbows detect Oncogenic Rearrangements of Signaling Molecules in Thyroid Tumors

Description: Altered signal transduction can be considered a hallmark of many solid tumors. In thyroid cancers the receptor tyrosine kinase (rtk) genes NTRK1 (Online Mendelian Inheritance in Man = OMIM *191315, also known as 'TRKA'), RET ('Rearranged during Transfection protooncogene', OMIM *164761) and MET (OMIM *164860) have been reported as activated, rearranged or overexpressed. In many cases, a combination of cytogenetic and molecular techniques allows elucidation of cellular changes that initiate tumor development and progression. While the mechanisms leading to overexpression of the rtk MET gene remain largely unknown, a variety of chromosomal rearrangements of the RET or NTKR1 gene could be demonstrated in thyroid cancer. Abnormal expressions in these tumors seem to follow a similar pattern: the rearrangement translocates the 3'-end of the rtk gene including the entire catalytic domain to an expressed gene leading to a chimeric RNA and protein with kinase activity. Our research was prompted by an increasing number of reports describing translocations involving ret and previously unknown translocation partners. We developed a high resolution technique based on fluorescence in situ hybridization (FISH) to allow rapid screening for cytogenetic rearrangements which complements conventional chromosome banding analysis. Our technique applies simultaneous hybridization of numerous probes labeled with different reporter molecules which are distributed along the target chromosome allowing the detection of cytogenetic changes at near megabase-pair (Mbp) resolution. Here, we report our results using a probe set specific for human chromosome 10, which is altered in a significant portion of human thyroid cancers (TC's). While rendering accurate information about the cytogenetic location of rearranged elements, our multi-locus, multi-color analysis was developed primarily to overcome limitations of whole chromosome painting (WCP) and chromosome banding techniques for fine mapping of breakpoints in papillary thyroid cancer (PTC).
Date: August 19, 2010
Creator: O'Brien, Benjamin; Jossart, Gregg H.; Ito, Yuko; Greulich-Bode, Karin M.; Weier, Jingly F.; Munne, Santiago et al.
Partner: UNT Libraries Government Documents Department