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Calibration of the Accuscan II In Vivo System for I-125 Thyroid Counting

Description: This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-125 thyroid counting. The source used for the calibration was a DOE manufactured Am-241/Eu-152 source contained in a 22 ml vial BEA Am-241/Eu-152 RMC II-1 with energies from 26 keV to 344 keV. The center of the detector housing was positioned 64 inches from the vault floor. This position places the approximate center line of the detector housing at the center line of the source in the phantom thyroid tube. The energy and efficiency calibration were performed using an RMC II phantom (Appendix J). Performance testing was conducted using source BEA Am-241/Eu-152 RMC II-1 and Validation testing was performed using an I-125 source in a 30 ml vial (I-125 BEA Thyroid 002) and an ANSI N44.3 phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibration including performance verification and validation counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-125 and verified in accordance with ANSI/HPS N13.30-1996 criteria.
Date: July 1, 2011
Creator: Perry, Ovard R. & Georgeson, David L.
Partner: UNT Libraries Government Documents Department

Calibration of the Accuscan II In Vivo System for I-131 Thyroid Counting

Description: This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-131 thyroid counting. The source used for the calibration was an Analytics mixed gamma source 82834-121 distributed in an epoxy matrix in a Wheaton Liquid Scintillation Vial with energies from 88.0 keV to 1836.1 keV. The center of the detectors was position 64-feet from the vault floor. This position places the approximate center line of the detectors at the center line of the source in the thyroid tube. The calibration was performed using an RMC II phantom (Appendix J). Validation testing was performed using a Ba-133 source and an ANSI N44.3 Phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibrations including verification counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-131 and verified in accordance with ANSI/HPS N13.30-1996 criteria.
Date: July 1, 2011
Creator: Perry, Orval R. & Georgeson, David L.
Partner: UNT Libraries Government Documents Department

Kinase Expression and Chromosomal Rearrangements in Papillary Thyroid Cancer Tissues: Investigations at the Molecular and Microscopic Levels

Description: Structural chromosome aberrations are known hallmarks of many solid tumors. In the papillary form of thyroid cancer (PTC), for example, activation of the receptor tyrosine kinase (RTK) genes, ret or the neurotrophic tyrosine kinase receptor type I (NTRK1) by intra- or interchromosomal rearrangements have been suggested as a cause of the disease. The 1986 accident at the nuclear power plant in Chernobyl, USSR, led to the uncontrolled release of high levels of radioisotopes. Ten years later, the incidence of childhood papillary thyroid cancer (chPTC) near Chernobyl had risen by two orders of magnitude. Tumors removed from some of these patients showed aberrant expression of the ret RTK gene due to a ret/PTC1 or ret/PTC3 rearrangement involving chromosome 10. However, many cultured chPTC cells show a normal G-banded karyotype and no ret rearrangement. We hypothesize that the 'ret-negative' tumors inappropriately express a different oncogene or have lost function of a tumor suppressor as a result of chromosomal rearrangements, and decided to apply molecular and cytogenetic methods to search for potentially oncogenic chromosomal rearrangements in Chernobyl chPTC cases. Knowledge of the kind of genetic alterations may facilitate the early detection and staging of chPTC as well as provide guidance for therapeutic intervention.
Date: July 7, 2009
Creator: Weier, Heinz-Ulrich; Kwan, Johnson; Lu, Chun-Mei; Ito, Yuko; Wang, Mei; Baumgartner, Adolf et al.
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

Radiogenic neoplasia in thyroid and mammary clonogens. Final progress report, 1 January 1987--31 December 1997

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 a leading dose-limiting effect of radiation exposure. The thyroid and mammary glands are among the most sensitive human tissues to radiogenic initiation of cancer, and there is a profoundly higher risk of neoplastic initiation in these glands among individuals irradiated before or during puberty than among those exposed in later life. The authors developed unique quantitative experimental models to investigate and characterize the cells of origin of thyroid and mammary cancers and the effects of radiation on them (C185). To study these progenitor cells in vivo it is necessary to have a system by which their concentrations, total numbers and responses to radiation and other factors can be measured. It is a truism that not all cells in a tissue are equally sensitive to neoplastic initiation. They reasoned that the progenitor cells are most likely members of that subpopulation that is necessary to maintenance of normal tissue cell numbers and to repair and replacement after tissue damage. They further reasoned that such cells would likely be responsive to specific mitogenic stimulation by hormones. On the basis of these considerations, they developed quantitative rat thyroid and mammary epithelial cell transplantation systems.
Date: July 10, 1998
Creator: Clifton, K.H.
Partner: UNT Libraries Government Documents Department

Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956)- An Assessment of Quantities released, Off-Site Radiation Doses, and Potential Excess Risks of Thyroid Cancer, Volume 1

Description: In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel appointed by Tennessee's Commissioner of Health. One of the major contaminants studied in the dose reconstruction was radioactive iodine, which was released to the air by X-10 (now called Oak Ridge National Laboratory) as it processed spent nuclear reactor fuel from 1944 through 1956. The process recovered radioactive lanthanum for use in weapons development. Iodine concentrates in the thyroid gland so health concerns include various diseases of the thyroid, such as thyroid cancer. The large report, ''Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956) - An Assessment of Quantities Released, Off-site Radiation Doses, and Potential Excess Risks of Thyroid Cancer,'' is in two volumes. Volume 1 is the main body of the report, and Volume 1A, which has the same title, consists of 22 supporting appendices. Together, these reports serve the following purposes: (1) describe the methodologies used to estimate the amount of iodine-131 (I-131) released; (2) evaluate I-131's pathway from air to vegetation to food to humans; (3) estimate doses received by human thyroids; (4) estimate excess risk of acquiring a thyroid cancer during ones lifetime; and (5) provide equations, examples of historical documents used, and tables of calculated values. Results indicate that females born in 1952 who consumed milk from a goat pastured a few miles east of X-10 received the highest doses from I-131 and would have had the highest risks of contracting thyroid ...
Date: July 1, 1999
Creator: Apostoaei, A.I.; Burns, R.E.; Hoffman, F.O.; Ijaz, T.; Lewis, C.J.; Nair, S.K. et al.
Partner: UNT Libraries Government Documents Department

Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956)- An Assessment of Quantities released, Off-Site Radiation Doses, and Potential Excess Risks of Thyroid Cancer- APPENDICES Appendices-Volume 1A

Description: This report consists of all the appendices for the report described below: In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel appointed by Tennessee's Commissioner of Health. One of the major contaminants studied in the dose reconstruction was radioactive iodine, which was released to the air by X-10 (now called Oak Ridge National Laboratory) as it processed spent nuclear reactor fuel from 1944 through 1956. The process recovered radioactive lanthanum for use in weapons development. Iodine concentrates in the thyroid gland so health concerns include various diseases of the thyroid, such as thyroid cancer. The large report, ''Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956) - An Assessment of Quantities Released, Off-site Radiation Doses, and Potential Excess Risks of Thyroid Cancer,'' is in two volumes. Volume 1 is the main body of the report, and Volume 1A, which has the same title, consists of 22 supporting appendices. Together, these reports serve the following purposes: (1) describe the methodologies used to estimate the amount of iodine-131 (I-131) released; (2) evaluate I-131's pathway from air to vegetation to food to humans; (3) estimate doses received by human thyroids; (4) estimate excess risk of acquiring a thyroid cancer during ones lifetime; and (5) provide equations, examples of historical documents used, and tables of calculated values as appendices. Results indicate that females born in 1952 who consumed milk from a goat pastured a few miles east of X-10 received the ...
Date: July 1, 1999
Creator: Apostoaei, A.I.; Burns, R.E.; Hoffman, F.O.; Ijaz, T.; Lewis, C.J.; Nair, S.K. et al.
Partner: UNT Libraries Government Documents Department

Air pathway report: Phase I of the Hanford Environmental Dose Reconstruction Project

Description: Phase 1 of the air-pathway portion of the Hanford Environmental Dose Reconstruction (HEDR) Project sought to determine whether dose estimates could be calculated for populations in the 10 counties nearest the Hanford Site from atmospheric releases of iodine-131 from the site from 1944--1947. Phase 1 demonstrated the following: HEDR-calculated source-term estimates of iodine-131 releases to the atmosphere were within 20% of previously published estimates; calculated vegetation concentrations of iodine-131 agree well with previously published measurements; the highest of the Phase 1 preliminary dose estimates to the thyroid are consistent with independent, previously published estimates of doses to maximally exposed individuals; and, relatively crude, previously published measurements of thyroid burdens for Hanford workers are in the range of average burdens that the HEDR model estimated for similar reference individuals'' for the period 1944--1947. Preliminary median dose estimates summed over the year 1945--1947 for the primary pathway, air-pasture-cow-milk-thyroid, ranged from low median values of 0.006 rad for upwind adults who obtained milk from backyard cows not on pasture to high median values of 68.0 rad for downwind infants who drank milk from pasture-fed cows. Extremes of the estimated range are a low of essentially zero to upwind adults and a high of almost 3000 rem to downwind infants. 37 refs., 37 figs., 2 tabs.
Date: July 1, 1991
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