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in subjects: "Biological Radiation Effects"  
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The role of constitutive and inducible processes in the response of human squamous cell carcinoma cell lines to ionizing radiation

Description: The inherent radiation sensitivity of the cells within a tumor is thought to contribute to the success or failure of radiation therapy. In vitro studies have shown that radiation sensitivity differences in squamous cell carcinoma cell lines reflect alterations in DNA repair. These alterations result from constitutive changes in chromosome organization, not radiation-inducible processes. While inducible responses may play some role in the radiation response of tumor cells, there is no evidence f… more
Date: January 1, 1993
Creator: Schwartz, J.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Relationship between cross section measurements and understanding radiation induced damage to biomolecules

Description: Experimental research performed at the Pacific Northwest Laboratory relating to energy deposition by energetic charged particles is described. How cross section data obtained from gaseous- and condensed-phase studies are related to understanding damage to biomolecules is discussed. Studies to date stress the need for information about energy deposition in individual interactions and show that multiple ionization may play a very significant role in biological damage. Current efforts to relate th… more
Date: October 1, 1993
Creator: DuBois, R. D. & Braby, L. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Assessment of Accidental Intakes of Uranyl Acetylacetonate (UAA)

Description: Uranyl acetylacetonate (UAA) is an organic complex of uranium used for military applications as a chemical catalyst in high explosives. It is prepared from depleted uranium metal (in lots of 5 kg to 7 kg) by dissolution in nitric acid, neutralization, and complexation with 2,4-pentanedione; the precipitate is dissolved in benzene and recrystallized, dried, ground, and packaged. About six workers at a small chemical company were exposed over a period of time to UAA powders during routine prepara… more
Date: December 1, 1993
Creator: Fisher, D. R. & Briant, J. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Methodology for estimating radiation dose rates to freshwater biota exposed to radionuclides in the environment

Description: The purpose of this report is to present a methodology for evaluating the potential for aquatic biota to incur effects from exposure to chronic low-level radiation in the environment. Aquatic organisms inhabiting an environment contaminated with radioactivity receive external radiation from radionuclides in water, sediment, and from other biota such as vegetation. Aquatic organisms receive internal radiation from radionuclides ingested via food and water and, in some cases, from radionuclides a… more
Date: August 1, 1993
Creator: Blaylock, B. G.; Frank, M. L. & O`Neal, B. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Involvement of recombination in x-ray mutagenesis of human cells

Description: Closely related human lymphoblastoid cell lines derived from WI-L2 differ greatly in their responses to X-irradiation. Compared with TK6 (ATCC CRL 8015), WI-L2-NS (ATCC CRL 8155) has an enhanced X-ray survival. The induction of mutation by X-rays is also markedly different. The hemizygous hprt locus is slightly more mutable in WI-L2-NS than in TK6, and the dose response fits best to a linear-quadratic curve rather than the linear fit of TK6X-ray induced mutation at the autosomal tk locus in het… more
Date: January 1, 1993
Creator: Amundson, S. A. (Los Alamos National Lab., NM (United States)); Xia, F. & Liber, H. L. (Harvard School of Public Health, Boston, MA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Biomedical user facility at the 400-MeV Linac at Fermilab

Description: In this paper, general requirements are discussed on a biomedical user facility at the Fermilab`s 400-MeV Linac, which meets the needs of biology and biophysics experiments, and a conceptual design and typical operations requirements of the facility is presented. It is assumed that no human patient treatment will take place in this facility. If human patients were treated, much greater attention would have to be paid to safeguarding the patients.
Date: December 1, 1993
Creator: Chu, W. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Health effects models for nuclear power plant accident consequence analysis. Modification of models resulting from addition of effects of exposure to alpha-emitting radionuclides: Revision 1, Part 2, Scientific bases for health effects models, Addendum 2

Description: The Nuclear Regulatory Commission (NRC) has sponsored several studies to identify and quantify, through the use of models, the potential health effects of accidental releases of radionuclides from nuclear power plants. The Reactor Safety Study provided the basis for most of the earlier estimates related to these health effects. Subsequent efforts by NRC-supported groups resulted in improved health effects models that were published in the report entitled {open_quotes}Health Effects Models for N… more
Date: May 1, 1993
Creator: Abrahamson, S.; Bender, M. A.; Boecker, B. B.; Scott, B. R. & Gilbert, E. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Air pollution effects field research facility: 3. UV-B exposure and monitoring system

Description: The Oak Ridge National Laboratory Outdoor UltraViolet-B (UV-B) Exposure and Monitoring Facility was developed in 1980 to provide well-controlled and -monitored exposure of specific terrestrial plant. species to elevated levels of ultraviolet (UV) radiation. The introduction of various anthropogenic agents into the earth`s stratosphere has resulted in a decrease in the volume of ozone (O{sub 3}) present here. The decrease in O{sub 3} has resulted in an increase in the level of UV radiation reach… more
Date: March 1, 1993
Creator: McEvers, J. A.; Hileman, M. S. & Edwards, N. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Expression of cytoskeletal and matrix genes following exposure to ionizing radiation: Dose-rate effects and protein synthesis requirements

Description: Experiments were designed to examine the effects of radiation dose-rate and of the protein synthesis inhibitor cycloheximide on expression of cytoskeletal elements ({gamma}- and {beta}-actin and {alpha}-tubulin) and matrix elements (fibronectin) in Syrian hamster embryo cells. Results demonstrated little effect of dose-rate for JANUS fission-spectrum neutrons when comparing expression of either a-tubulin or fibronectin genes. Past work had already documented similar results for expression of ac… more
Date: December 31, 1993
Creator: Woloschak, G. E.; Felcher, P. & Chang-Liu, Chin-Mei
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of EMP fields on cell membrane potentials

Description: A simple model is presented for cell membrane potentials induced during exposure to electromagnetic pulse (EMP). Using calculated values of internal electric field strength induced during EMP exposure, the model predicts that cell membrane potentials of about 100 mV may be induced for time frames on the order of 10 ns. Possible biological effects of these potentials including electroporation area discussed.
Date: June 1, 1993
Creator: Gailey, P. C. & Easterly, C. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The role of constitutive and inducible processes in the response of human squamous cell carcinoma cell lines to ionizing radiation

Description: The inherent radiation sensitivity of the cells within a tumor is thought to contribute to the success or failure of radiation therapy. In vitro studies have shown that radiation sensitivity differences in squamous cell carcinoma cell lines reflect alterations in DNA repair. These alterations result from constitutive changes in chromosome organization, not radiation-inducible processes. While inducible responses may play some role in the radiation response of tumor cells, there is no evidence f… more
Date: June 1, 1993
Creator: Schwartz, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

HIV transcription is induced with cell killing

Description: In this report, we demonstrate that this induction of HIV-LTR transcription occurs when stably transfected HeLa cells are exposed to agents which mediate cell killing, such as UV radiation, electroporation of sucrose buffer, prolonged heating, and low and high pH. Cells cultured following UV exposure demonstrated a peak in CAT expression that is evident in viable (but not necessarily cell division-competent) cells 24 h after exposure; this inductive response continued until at least 72 h after … more
Date: November 1, 1993
Creator: Woloschak, Gayle E.; Schreck, Steven; Chang-Liu, Chin-Mei; Panozzo, John & Libertin, Claudia R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Combined effects of ionizing radiation and cycloheximide on gene expression

Description: Experiments were done to determine the effects of ionizing radiation exposure on expression of genes following exposure of Syrian hamster embryo (SHE) cells to the protein synthesis inhibitor cycloheximide (including such genes as {beta}-actin, c-fos, H4-histone, c-myc, c-jun, Rb, and p53). Results revealed that when ionizing radiations (either fission-spectrum neutrons or {gamma}-rays) were administered 15 min following the cycloheximide treatment of SHE cells, the radiation exposure reduced c… more
Date: November 1, 1993
Creator: Woloschak, G. E.; Felcher, P. & Chang-Liu, Chin-Mei
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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 neop… more
Date: July 30, 1993
Creator: Clifton, K. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Initial ultraviolet-B intensity data at Lawrence Livermore National Laboratory

Description: A measurement of UV-B reaching the ground has been established at the Lawrence Livermore National Laboratory. The instrument is the same as those operated by the National Institute for Water and Atmospheric Research in their network in New Zealand. The wavelength response of the radiometer is similar to the response of human skin to UV-B. Intensity data are collected by averaging meter readings over 10 minutes from 6:00 am to 6:00 pm Pacific Standard Time, then converting to effective UV-B inte… more
Date: October 1, 1993
Creator: Patten, K. O. Jr.; Wuebbles, D. J. & Smith, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

What can be learned from epidemiologic studies of persons exposed to low doses of radiation?

Description: The main objective of radiation risk assessment is to determine the risk of various adverse health effects associated with exposure to low doses and low dose rates. Extrapolation of risks from studies of persons exposed at high doses (generally exceeding 1 Sv) and dose rates has been the primary approach used to achieve this objective. The study of Japanese atomic bomb survivors in Hiroshima and Nagasaki has played an especially important role in risk assessment efforts. A direct assessment of … more
Date: April 1, 1993
Creator: Gilbert, E. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Research for electric energy systems -- an annual report

Description: This report documents the technical progress in the two investigations which make up the project {open_quotes}Support of Research Projects for Electrical Energy Systems,{close_quotes} Department of Energy Task Order Number 137, funded by the US Department of Energy and performed by the Electricity Division of the National Institute of Standards and Technology (NIST). The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of … more
Date: October 1, 1993
Creator: Anderson, W. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Environmental Assessment for moving the Pacific Northwest Laboratory radon generators from Life Sciences Laboratory II, Richland North Area, to Life Sciences Laboratory I, 300 Area, and their continued use in physical and biological research

Description: The Pacific Northwest Laboratory (PNL) radon generators are a core resource of the overall U. S. Department of Energy`s (DOE) Radon Research Program and are administratively controlled within the ``Radon Hazards in Homes`` project. This project primarily focuses on radon exposures of animals and addresses the major biologic effects and factors influencing risks of indoor radon exposures. For example, the ``Mechanisms of Radon Injury`` and ``In vivo/In vitro Radon-Induced Cellular Damage`` proje… more
Date: September 1, 1993
Creator: Nelson, I. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanisms for radiation damage in DNA. Progress report, June 1, 1993--May 31, 1994

Description: In this project the author has proposed several mechanisms for radiation damage to DNA and its constituents, and has detailed a series of experiments utilizing electron spin resonance spectroscopy, HPLC, GC-mass spectroscopy and ab initio molecular orbital calculations to test the proposed mechanisms. In this years work he has completed several experiments on the role of hydration water on DNA radiation damage, continued the investigation of the localization of the initial charges and their rea… more
Date: December 1, 1993
Creator: Sevilla, M. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Health effects models for nuclear power plant accident consequence analysis. Part 1, Introduction, integration, and summary: Revision 2

Description: This report is a revision of NUREG/CR-4214, Rev. 1, Part 1 (1990), Health Effects Models for Nuclear Power Plant Accident Consequence Analysis. This revision has been made to incorporate changes to the Health Effects Models recommended in two addenda to the NUREG/CR-4214, Rev. 1, Part 11, 1989 report. The first of these addenda provided recommended changes to the health effects models for low-LET radiations based on recent reports from UNSCEAR, ICRP and NAS/NRC (BEIR V). The second addendum pre… more
Date: October 1, 1993
Creator: Evans, J. S.; Abrahmson, S.; Bender, M. A.; Boecker, B. B.; Scott, B. R. & Gilbert, E. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dosimetry at the Los Alamos Critical Experiments Facility: Past, Present, and Future

Description: Although the primary reason for the existence of the Los Alamos Critical Experiments Facility is to provide basic data on the physics of systems of fissile material, the physical arrangements and ability to provide sources of radiation have led to applications for all types of radiation dosimetry. In the broad definition of radiation phenomena, the facility has provided sources to evaluate biological effects, radiation shielding and transport, and measurements of basic parameters such as the ev… more
Date: October 1993
Creator: Malenfant, Richard E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron interactions with biological tissue. Progress report, 1992--1993

Description: The first area of research focuses on track structure effects in neutron microdosimetry and nanodosimetry. This is an investigation of the effect of proton energy-loss straggling and the associated transport of energy by secondary electrons on neutron event-size distributions in small sites. Secondly, energy deposition spectra and their moments for fast neutrons are investigated. Using calculated charged particle initial spectra and slowing-down spectra the authors can calculate the energy depo… more
Date: December 31, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Lung cancer in uranium miners: A tissue resource and pilot study. Progress report, September 25, 1992--May 31, 1993

Description: This project involves two related activities directed toward understanding respiratory carcinogenesis in radon-exposed former uranium miners. The first activity involves a continuation of the tissue resource of lung cancer cases from former underground uranium miners and comparison cases from non-miners. The second activity is a pilot study for a proposed longitudinal study of respiratory carcinogenesis in former uranium miners. The objectives are to facilitate the investigation of molecular ch… more
Date: May 1, 1993
Creator: Samet, J.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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c-jun gene expression in human cells exposed to either ionizing radiation or hydrogen peroxide

Description: We investigated the role of reactive oxygen intermediates (ROIs) and protein kinase C (PKC) in radiation- and H{sub 2}O{sub 2}-evoked c-jun gene expression in human HL-205 cells. This induction of c-jun gene expression could be prevented by pretreatment of the cells with Nacetylcysteine (an antioxidant) or H7 (a PKC and PKA inhibitor) but not by HA1004, a PKA inhibitor, suggesting a role for ROls and PKC in mediating c-jun gene expression. We also investigated potential differences in c-jun gen… more
Date: June 1, 1993
Creator: Collart, F.R.; Horio, M. & Huberman, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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