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in subjects: "Rodents"

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Studies in iodine metabolism. Progress report and publications, 1979-1980

Research programs for the years 1978-1980 is reported. The following subject areas are discussed: (1) iodine 131 monitoring in thyroids of sheep, cattle and humans; (2) radium monitoring in cattle thyroids; (3) the relationship of thyroid function to seizures in rats; (4) the effect of KSCN on thyroglobulin in mice; and (5) studies on excessive iodide intake. (ACR)

Date: January 1, 1980

Creator: Van Middlesworth, L

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Genetic influence on brain catecholamines: high brain norepinephrine in salt-sensitive rats

Rats genetically sensitive to salt-induced hypertension evinced higher levels of plasma norepinephrine and epinephrine than rats genetically resistant to hypertension. The hypertension-sensitive rats showed higher hypothalamic norepinephrine and lower epinephrine than resistant rats. In response to a high salt diet, brain stem norepinephrine increased in sensitive rats while resistant rats exhibited a decrease on the same diet.

Date: January 1, 1980

Creator: Iwai, J; Friedman, R & Tassinari, L

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Inhalation developmental toxicology studies: Teratology study of n-hexane in rats: Final report

The straight chain hydrocarbon, n-hexane, is a volatile, ubiquitous solvent used in industrial, academic, and smaller commercial environments. The significant opportunity for women of child-bearing age to be exposed to this chemical prompted the undertaking of a study to assess the developmental toxicity of n-hexane in an animal model. Timed-pregnant (30 animals per group) and virgin (10 animals per group) Sprague-Dawley rats were exposed to 0 (filtered air), 200, 1000, and 5000 ppM n-hexane (9… more

Date: December 1, 1987

Creator: Mast, T.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Comments on mutagenesis risk estimation

Several hypotheses and concepts have tended to oversimplify the problem of mutagenesis and can be misleading when used for genetic risk estimation. These include: the hypothesis that radiation-induced mutation frequency depends primarily on the DNA content per haploid genome, the extension of this concept to chemical mutagenesis, the view that, since DNA is DNA, mutational effects can be expected to be qualitatively similar in all organisms, the REC unit, and the view that mutation rates from c… more

Date: January 1, 1976

Creator: Russell, W.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Biomedical research with cyclotron produced radionuclides. Progress report, February 1, 1981-December 31, 1981

Progress is reported in the following areas: evaluation of chemotherapeutic regimens in solid tumors using /sup 13/N-labelled amino acids; organ imaging with /sup 13/N-labelled L-amino acids; imaging with /sup 111/In-labelled-autologous platelets; synthesis and biological studies of /sup 111/In-labelled ammonia and L-amino acids; synthesis and evaluation for pancreatic imaging of /sup 11/C-labelled amino acides; radioisotope monitoring of myocardiol function; synthesis of /sup 11/C-labelled pre… more

Date: September 1, 1981

Creator: Laughlin, J.S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Genetic changes in Mammalian cells transformed by helium cells

Midterm Syrian Hamster embryo (SHE) cells were employed to study high LET-radiation induced tumorigenesis. Normal SHE cells (secondary passage) were irradiated with accelerated helium ions at an incident energy of 22 MeV/u (9--10 keV/{mu}m). Transformed clones were isolated after growth in soft agar of cells obtained from the foci of the initial monolayer plated postirradiation. To study the progression process of malignant transformation, the transformed clones were followed by monolayer subcu… more

Date: November 1, 1990

Creator: Durante, M.; Grossi, G. (Naples Univ. (Italy). Dipt. di Scienze Fisiche); Yang, T.C. & Roots, R. (Lawrence Berkeley Lab., CA (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cytometry of mammalian sperm

Male germ cells respond dramatically to a variety of insults and are important reproductive dosimeters. Semen analyses are very useful in studies on the effects of drugs, chemicals, and environmental hazards on testicular function, male fertility and heritable germinal mutations. The accessibility of male cells makes them well suited for analytical cytology. We might automate the process of determining sperm morphology but should not do so solely for increased speed. Rather, richer tangible ben… more

Date: October 11, 1983

Creator: Gledhill, B.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Oil shale health and environment research

While there have been sporadic efforts to demonstrate certain shale oil extraction technologies in recent years, none of the techniques have been thoroughly analyzed to determine the extent of potential occupational health impacts and even those technologies that have been demonstrated cannot be regarded as typical of a scaled-up, fully mature industry. Industrial hygiene studies have served to identify operations within certain technologies where mitigating methods can and should be applied to… more

Date: January 1, 1980

Creator: Holland, L.M. & Tillery, M.I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Spermatogonial stem cell renewal following irradiation

The spermatogonial cell renewal system can maintain function and a steady level of cell population for relatively long periods of continuous low-level irradiation indicating that there does not appear to be a serious accumulation, over many generations, of damage affecting proliferation. Provided the dose-rate is quite low, there is an effective selective removal of damaged cells with almost complete repair of cellular nonlethal damage. At dose-rates greater than 2 rad/day, spermatogonia are ve… more

Date: May 1, 1979

Creator: Fabrikant, Jacob I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Sunlight activation of shale-oil byproducts as measured by genotoxic effects in cultured Chinese hamster cells

Activation of certain classes of promutagens/procarcinogens can be accomplished by exposure to various radiation sources. Retort processes currently in use in the production of shale oil generate significant quantities of process waters which contain a wide spectrum of uv-absorbing, organic material. Photoactivation of these waters with an artificial source of NUV results in genotoxic events in cultured mammalian cells. Since significant amounts (2 to 4%) of solar radiation reaching the earth's… more

Date: January 1, 1981

Creator: Strniste, G.F.; Chen, D.J. & Okinaka, R.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Habitat associations of vertebrate prey within the controlled area study zone

Twelve study locations were established in nine habitat types in the vicinity of the proposed reference repository location. Eight species of small mammals were captured. Great Basin pocket mice (Perognathus parvus) comprised the majority of individuals captured, followed by deer mice (Peromyscus maniculatus), Northern pocket gopher (Thomomys talpoides), Western harvest mouse (Reithrodontomys megalotus), Grasshopper mouse (Onychomys leucogaster), Montane vole, (Microtus montanus), House mouse (… more

Date: March 1, 1988

Creator: Marr, N. V.; Brandt, C. A.; Fitzner, R. E. & Poole, L. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Tritium toxicity program in the Medical Department, Brookhaven National Laboratory

It is possible to detect somatic, cytogenetic and genetic effects resulting from exposures at 33 to 100 times the mpc's for tritiated water (HTO). The reduction in bone marrow cells in animals maintaining normal total cellularity demonstrate both the presence of an effect at the primitive cell level as well as the animal's ability to compensate for this effect by recruiting stem cells from the G/sub 0/ resting state. This evidence of damage together with the observed cytogenetic changes leads o… more

Date: January 1, 1983

Creator: Carsten, A.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation-induced mesotheliomas in rats

Mesotheliomas have been reported in rats that inhaled plutonium, but these tumors have not been extensively studied. To investigate a possible role for inhaled radionuclides in the induction of mesotheliomas, four life-span studies conducted at the Inhalation Toxicology Research Institute are reviewed. A total of 3076 F344 rats were exposed by inhalation to aerosols of {sup 239}PuO{sub 2}, mixed uranium-plutonium oxide, or {sup 144}CeO{sub 2}. Results showed that a low incidence of pleural meso… more

Date: January 1, 1990

Creator: Hahn, F. F.; Haley, P. J.; Hubbs, A. F.; Hoover, M. D. & Lundgren, D. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Biological effects of static magnetic fields: a selective review with emphasis on risk assessment

Rather than focusing on literature per se, the current study determines the status of magnetic field information that is applicable to risk assessment. Hence, an attempt is made to identify both the literature that is useful to the goal of risk assessment and a framework within which risk assessment methodologies can be derived. From this selected review, it is concluded that three areas exist for which adequate information can be found to begin modelling: disease induction, reproduction and de… more

Date: April 1, 1982

Creator: Easterly, C. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

New methodlogy for measuring damage to respiratory tract cells using flow-system cell-analysis techniques

Automated flow-system cell-analysis techniques provide a new method for determining damage to respiratory tract cells in humans exposed by inhalation of environmental pollutants such as from the production of synthetic fuels from coal and oil shale. This paper describes results of preliminary experiments designed to develop flow-system instrumentation methods for measuring biological damage to respiratory tract cells using the Syrian hamster as a model. Hamster respiratory tract cell samples we… more

Date: January 1, 1977

Creator: Steinkamp, J. A.; Hansen, K. M.; Wilson, J. S. & Salzman, G. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Translocation of particles to the pleural space and tracheobronchial lymph nodes following lung deposition

The translocation of particles from the alveolar compartment to the pleural space and tracheobronchial lymph nodes was investigated in rats over a 30 day period following the intrapulmonary instillation of 4 x 10/sup 8/ polystyrene microspheres (1.9 ..mu..m dia.). In initial studies, approx. =10/sup 4/ particles were found in the pleural space compartment on Days 1, 14 and 30 after particle deposition, and most of these were cell-associated. Subsequent pleural space studies indicated, however, … more

Date: January 1, 1985

Creator: Lehnert, B. E.; Valdez, Y. E. & Hyler, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Biophysical and biomathematical adventures in radiobiology

Highlights of my biophysical and biomathematical adventures in radiobiology is presented. Early adventures involved developing state-vector models'' for specific harmful effects (cell killing, life shortening) of exposure to radiation. More recent adventures led to developing hazard-function models'' for predicting biological effects (e.g., cell killing, mutations, tumor induction) of combined exposure to different toxicants. Hazard-function models were also developed for predicting harm to man… more

Date: January 1, 1991

Creator: Scott, B.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Characterization of cell suspensions from solid tumors

The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with differen… more

Date: July 10, 1985

Creator: Pallavicini, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Applications of Quantitative Whole Body Autoradiographic Technique in Radiopharmaceutical Research

The routine evaluation of radiopharmaceuticals involves dissecting tissue distribution studies (DTDS) and gamma or positron imaging. DTDS have the following disadvantages: since not all tissues can always be sampled, sites of radiopharmaceutical uptake may be missed and because the procedure involves weighing of dissected tissue samples, the spatial resolution of this method is low and determined by the smallest amount that can be weighed accurately. Gamma camera imaging and positron emission t… more

Date: January 1, 1982

Creator: Som, P.; Oster, Z. H.; Yonekura, Y.; Meyer, M. A.; Fand, I. & Brill, A. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation effects in space

The paper discusses the radiation environment in space that astronauts are likely to be exposed to. Emphasis is on proton and HZE particle effects. Recommendations for radiation protection guidelines are presented. (ACR)

Date: January 1, 1986

Creator: Fry, R.J.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Chimpanzee chromosome 13 is homologous to human chromosome 2p

Similarities between human and chimpanzee chromosomes are shown by chromosome banding techniques and somatic cell hybridization techniques. Cell hybrids were obtained from the chimpanzee lymphocyte LE-7, and the Chinese hamster mutant cell, Gal-2. Experiments showed that the ACPL, MDHs, and Gal-Act genes could be assigned to chimpanzee chromosome 13, and since these genes have been assigned to human chromosme 2p, it is suggested that chimpanzee chromosome 13 is homologous to human chromosome 2p… more

Date: January 1, 1977

Creator: Sun, N. C.; Sun, C. R.Y. & Ho, T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dosimetry of inhaled plutonium-239 dioxide in rodent lung: a morphometric study

Morphometric analysis of rat and hamster lung did not demonstrate any extensive changes in lung composition or structure following inhalation exposure to /sup 239/Pu0/sub 2/ at levels near that for maximum tumor yield in rats. The problem of dosimetry for this compound thus appears to be relatively uncomplicated by any major radiation-induced pathological alterations in the lung. Rat and hamster lung were found to be similar in structure and composition, with few significant differences which c… more

Date: June 1, 1979

Creator: Rhoads, K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Division of Biological and Medical Research annual report 1978

The research during 1978 in the Division of Biological and Medical Research, Argonne National Laboratory, is summarized. Studies related to nuclear energy include responses of beagles to continuous low-level /sup 60/Co gamma radiation, and development of leukemic indicators; comparison of lifetime effects in mice of low-level neutron and /sup 60/Co gamma radiation; genetic effects of high LET radiations; and metabolic and therapeutic studies of heavy metals. Studies of nonnuclear energy sources… more

Date: January 1, 1978

Creator: Rosenthal, M.W. (ed.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Respiratory tract carcinogenesis induced by radionuclides in the Syrian hamister

Syrian hamsters were exposed to lung irradiation by various modalities that differed in degree of localization and the fraction of lung exposed. The animals were given alpha emitters under several exposure conditions: intratracheal (IT) instillation of /sup 210/Po and /sup 239/PuO/sub 2/-ZrO/sub 2/ microspheres; inhalation (INH) of /sup 238/ /sup 239/PuO/sub 2/-ZrO/sub 2/ particles; and/or intravenous (IV) injection of /sup 238/ /sup 239/PuO/sub 2/-ZrO/sub 2/ microspheres. Beta-emitting /sup 14… more

Date: January 1, 1979

Creator: Smith, D. M.; Thomas, R. G. & Anderson, E. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department