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Thorium in occupationally exposed men.

Description: Higher than environmental levels of {sup 232}Th have been found in autopsy samples of lungs and other organs from four former employees of a thorium refinery. Working periods of the subjects ranged from 3 to 24 years, and times from end of work to death ranged from 6 to 31 years. Examination of the distribution of thorium among the organs revealed poor agreement with the distribution calculated from the dosimetric models in Publication 30 of the International Commission on Radioprotection (ICRP). Concentrations in the lungs relative to pulmonary lymph nodes, bone or liver were much higher than calculated from the model for class Y thorium and the exposure histories of the workers. Much better agreement was found with more recently proposed models in Publications 68 and 69 of the ICRP. Radiation doses estimated from the amounts of thorium in the autopsy samples were compatible with health studies that found no significant difference in mortality from that of the general population of men in the US.
Date: February 24, 1999
Creator: Stehney, A. F.
Partner: UNT Libraries Government Documents Department

A SUBCHRONIC INHALATION STUDY OF FISCHER 344 RATS EXPOSED TO 0, 0.4, 1.4 OR 4.0 PPM ACROLEIN.

Description: Fischer 344 rats were exposed to 0.0, 0.4, 1.4, or 4.0 ppm acrolein for 62 days. The major objective of the study was to relate the results of a series of pulmonary function tests to biochemical and pathological alterations observed in the lung. Cytological and reproductive potential endpoints were also assessed after acrolein exposure. Rats were exposed to acrolein for 6 hours/day, 5 days/week for 62 days. Mortality was observed only in the 4.0 ppm chamber where 32 of 57 exposed males died; however, none of the 8 exposed females died. Most of the mortality occurred within the first 10 exposure days. Histologic examination indicated that the animals died of acute bronchopneumonia. The surviving males and females exposed to 4.0 ppm acrolein gained weight at a significantly slower rate than control animals. The growth of both sexes in the 0.4 and 1.4 ppm groups was similar to that of their respective controls. Histopathologic examination of animals after 62 days of exposure revealed bronchiolar epithelial necrosis and sloughing, bronchiolar edema with macrophages, and focal pulmonary edema in the 4.0 ppm group. These lesions were, in some cases, associated with edema of the trachea and peribronchial lymph nodes, and acute rhinitis which indicated an upper respiratory tract effect of acrolein. Of particular interest was the variability of response between rats in the 4.0 ppm group, some not affected at all while others were moderately affected. Intragroup variability in toxicity was also apparent in the 1.4 ppm exposure group where only 3 of 31 animals examined had lesions directly related to acrolein exposure. Extra respiratory organs appeared unaffected.
Date: October 1, 1981
Creator: KUTZMAN,R.S.
Partner: UNT Libraries Government Documents Department

Foot & Mouth Disease & Ulcerative/Vesicular Rule-outs: Challenges Encountered in Recent Outbreaks

Description: Foot and mouth disease (FMD) is a highly infectious and contagious viral disease affecting bovidae (cattle, zebus, domestic buffaloes, yaks), sheep, goats, swine, all wild ruminants and suidae. Camelidae (camels, dromedaries, llamas, vicunas) have low susceptibility. Foot and mouth disease is caused by a RNS virus of the family Picornaviridae, genus Aphthovirus. There are seven immunologically distinct serotypes: A, O, C, SAT1, SAT2, SAT3, Asia 1. Foot and mouth disease causes significant economic loss both to countries who manage it as an endemic disease (with or without vaccination), as well as those FMD free countries which may become infected. The mortality rate is low in adult animals, but often higher in young due to myocarditis. Foot and mouth disease is endemic in parts of Asia, Africa, the Middle East and South America (sporadic outbreaks in free areas). The Office of International Epizootics (OIE), also referred to the World Organization for Animal Health maintains an official list of free countries and zones.1 The OIE Terrestrial Code (Chapter 2.2.10) provides detailed information on the categories of freedom that can be allocated to a country as well as guidelines for the surveillance for foot and mouth disease (Appendix 3.8.7). In short, countries may be completely free of FMD, free with vaccination or infected with foot and mouth disease virus (FMDV). Source of FMDV include incubating and clinically affected animals with virus present in breath, saliva, faeces, urine, milk and semen. In experimental settings virus has been detected in milk several days before the onset of clinical signs2. Additional sources of virus are meat and by-products in which pH has remained above 6.0 as well as persistently infected carrier animals. Carrier animals may include cattle and water buffalo; convalescent animals and exposed vaccinates (virus persists in the oropharynx for up to 30 months in ...
Date: January 28, 2008
Creator: Hullinger, P
Partner: UNT Libraries Government Documents Department

The expression level of HJURP has an independent prognostic impact and predicts the sensitivity to radiotherapy in breast cancer

Description: Introduction: HJURP (Holliday Junction Recognition Protein) is a newly discovered gene reported to function at centromeres and to interact with CENPA. However its role in tumor development remains largely unknown. The goal of this study was to investigate the clinical significance of HJURP in breast cancer and its correlation with radiotherapeutic outcome. Methods: We measured HJURP expression level in human breast cancer cell lines and primary breast cancers by Western blot and/or by Affymetrix Microarray; and determined its associations with clinical variables using standard statistical methods. Validation was performed with the use of published microarray data. We assessed cell growth and apoptosis of breast cancer cells after radiation using high-content image analysis. Results: HJURP was expressed at higher level in breast cancer than in normal breast tissue. HJURP mRNA levels were significantly associated with estrogen receptor (ER), progesterone receptor (PR), Scarff-Bloom-Richardson (SBR) grade, age and Ki67 proliferation indices, but not with pathologic stage, ERBB2, tumor size, or lymph node status. Higher HJURP mRNA levels significantly decreased disease-free and overall survival. HJURP mRNA levels predicted the prognosis better than Ki67 proliferation indices. In a multivariate Cox proportional-hazard regression, including clinical variables as covariates, HJURP mRNA levels remained an independent prognostic factor for disease-free and overall survival. In addition HJURP mRNA levels were an independent prognostic factor over molecular subtypes (normal like, luminal, Erbb2 and basal). Poor clinical outcomes among patients with high HJURP expression werevalidated in five additional breast cancer cohorts. Furthermore, the patients with high HJURP levels were much more sensitive to radiotherapy. In vitro studies in breast cancer cell lines showed that cells with high HJURP levels were more sensitive to radiation treatment and had a higher rate of apoptosis than those with low levels. Knock down of HJURP in human breast cancer cells using shRNA reduced the sensitivity ...
Date: June 25, 2010
Creator: Hu, Zhi; Huang, Ge; Sadanandam, Anguraj; Gu, Shenda; Lenburg, Marc E; Pai, Melody et al.
Partner: UNT Libraries Government Documents Department

Biomedical probe using a fiber optic coupled scintillator

Description: A biomedical scintillation counter similar in size to a fiberoptic gastroscope was fabricated to count low concentrations of internal radioactivity. The probe was built specifically to count the uranium L x rays (average energy 17 keV) emitted in the decay of plutonium located in the tracheobronchial lymph nodes. Plutonium is found in the trachenbronchial lymph nodes due to translocation of inhaled insoluble plutonium compounds. Efforts with the scintillation technique resulted in a probe with higher sensitivity than a previously developed solid-state avalanche diode probe. Although the probe was developed specifically for counting plutonium, it can be readily applied to counting other isotopes with low energy photons such as /sup 131/I, /sup 125/I, / sup 197/Hg, /sup 67/Ga, /sup 133 /Xe, /sup 99m/Tc, etc. The physical features and the performance of the fiber optic coupled scintillation counter are described, and the probe is compared with similar solid-state probes. Previous fiber optic probes have been built for dosimetry; however, the present probe is designed for low background, low energy, high sensitivity photon counting. (WHK)
Date: January 1, 1973
Creator: Swinth, K.L. & Ewins, J.H.
Partner: UNT Libraries Government Documents Department

Present status of polonium tolerance estimations

Description: This report contains a summary of biological information on distribution, excretion, and toxicity of polonium; a comparison of results obtained when maximum permissible exposure rates for man are calculated from available data by different methods; and a critical evaluation of the present status of Po tolerance estimates. A maximum permissible body content of the order of 0.2 {mu}c/70 Kg man is obtained by two methods. Applying an urinary excretion rate of 0.1% of body content/day, effective half-life of 34 days, and certain corrections for the non-exponential nature of Pb excretion, maximum permissible air and water concentrations and urinary excretion rates have been computed. Extrapolation from present data to calculations of tolerance levels in man is still difficult, and there appears to be no substitute for actual long term experiments. On the other hand, permissible exposure levels quoted herein appear to be, to a large extent, consistent with conservative practice.
Date: October 14, 1948
Creator: Hursh, J.B. & Stannard, J.N.
Partner: UNT Libraries Government Documents Department

BRCA1 loss pre-existing in small subpopulations of prostate cancer is associated with advanced disease and metastatic spread to lymph nodes and peripheral blood

Description: A recent study concluded that serum prostate specific antigen (PSA)-based screening is beneficial for reducing the lethality of PCa, but was also associated with a high risk of 'overdiagnosis'. Nevertheless, also PCa patients who suffered from organ confined tumors and had negative bone scans succumb to distant metastases after complete tumor resection. It is reasonable to assume that those tumors spread to other organs long before the overt manifestation of metastases. Our current results confirm that prostate tumors are highly heterogeneous. Even a small subpopulation of cells bearing BRCA1 losses can initiate PCa cell regional and distant dissemination indicating those patients which might be at high risk of metastasis. A preliminary study performed on a small cohort of multifocal prostate cancer (PCa) detected BRCA1 allelic imbalances (AI) among circulating tumor cells (CTCs). The present analysis was aimed to elucidate the biological and clinical role of BRCA1 losses on metastatic spread and tumor progression in prostate cancer patients. Experimental Design: To map molecular progression in PCa outgrowth we used FISH analysis of tissue microarrays (TMA), lymph node sections and CTC from peripheral blood. We found that 14% of 133 tested patients carried monoallelic BRCA1 loss in at least one tumor focus. Extended molecular analysis of chr17q revealed that this aberration was often a part of larger cytogenetic rearrangement involving chr17q21 accompanied by AI of the tumor suppressor gene PTEN and lack of the BRCA1 promoter methylation. The BRCA1 losses correlated with advanced T stage (p < 0.05), invasion to pelvic lymph nodes (LN, p < 0.05) as well as BR (p < 0.01). Their prevalence was twice as high within 62 LN metastases (LNMs) as in primary tumors (27%, p < 0.01). The analysis of 11 matched primary PCa-LNM pairs confirmed the suspected transmission of genetic abnormalities between those two sites. ...
Date: March 19, 2010
Creator: Bednarz, Natalia; Eltze, Elke; Semjonow, Axel; Rink, Michael; Andreas, Antje; Mulder, Lennart et al.
Partner: UNT Libraries Government Documents Department

SEMIANNUAL REPORT TO THE ATOMIC ENERGY COMMISSION

Description: Data are summarized from a series of recently published papers which indicate that the tissue iron enzymes as well as the blood hemoglobin level play a role in the iron-deficiency state. Results from a study of the derivation, roles and fate of the antibody-forming cell in the rat indicate that antibody- forming cells in lymph nodes may be released to circulate in the efferent lymph and peripheral blood. Evidence indicates that the circulating cells may still contain formed antibody. Because of thcir form these circulating elements are designated lymphocytes. Strong evidence also implicates the plasma cell in the immune phenomenon. It appears that thc circulating blood contains two small round cells, one produced in the germinal centers of the spleen and other lymphatic tissue and having no known relationship to antibody production, while the other is apparently produced in the splenic red pulp, contains antibody, and is related intimately to antibody synthesis. In terms of site of production and function the two cells appear unrelated. Papers included which have been accepted for publication cover the effect of concurrent feeding of Tween 80 on the carcinogenicity of orally-administered 3-methylcholanthrene, data on the long- term survival of irrailiated mice treated with homologous tissue suspensions, a new modality in brachytherapy based on isotopes decaying by electron capture, the distribution of intraperitoneal radiocolloids, acquired tolerance to mouse leukemia in rats, and the determination of metabolites of cardiac glycosides in human urine. A list of staff publications during the period is included. (For preceding period see ACRH-10.) (C.H.)
Date: March 1, 1959
Creator: Jacobson, L.O. & Pfau, A. eds.
Partner: UNT Libraries Government Documents Department

Translocation dynamics of 239-plutonium

Description: >Thesis. The translocation dynamics of /sup 239/Pu(NO/sub 3/)/sub 4/ and /sup 239/PuO/sub 2/ from ulated puncture wounds in the paws of beagle dogs were studied. The difference between the more soluble Pu(NO/sub 3/)/sub 4/ form the insoluble high fired PuO/sub 2 particles was assumed to bring about highly differing translocation dynamics from the wound site, through lymphatic channels into the system's circulation and to organs of deposition and of excretion. There was rapid movement of Pu from the paw to the first major lymph node with a resulting buildup and regression pattern for activity within the node. Differential translocation, concentration, retention, and excretion of Pu and Am were demonstrated with both chemical forms. The effectiveness of DTPA administration for Pu removal from the body was dependent on the chemical form of the Pu contaminant. ( CH)
Date: October 1, 1973
Creator: Bistline, R.W.
Partner: UNT Libraries Government Documents Department

Lymph node clearance of plutonium from subcutaneous wounds in beagles

Description: The lymph node clearance of /sup 239/Pu O/sub 2/ administered as insoluble particles from subcutaneous implants was studied in adult beagles to simulate accidental contamination of hand wounds. External scintillation data were collected from the popliteal lymph nodes of each dog after 9.2 to 39.4 mu Ci of plutonium oxide was subcutaneously implanted into the left or right hind paws. The left hind paw was armputated 4 weeks after implantation to prevent continued deposition of plutonium oxide particles in the left popliteal lymph node. Groups of 3 dogs were sacrificed 4, 8, 16, and 32 weeks after plutonium implantation for histopathologic, electron microscopic, and radiochemical analysis of regional lymph nodes. An additional group of dogs received treatment with the chelating agent diethyenetriaminepentaacetic acid (DTPA). Plutonium rapidly accumulated in the popliteal lymph nodes after subcutaneous injection into the hind paw, and 1 to 10% of the implant dose was present in the popliteal lymph nodes at the time of necropsy. Histopathologic changes in the popliteal lymph nodes with plutonium particles were characterized primarily by reticular cell hyperplasia, increased numbers of macrophages, necrosis, and fibroplasia. Eventually, the plutonium particles became sequestered by scar tissue that often replaced the entire architecture of the lymph node. Light microscopic autoradiographs of the popliteal lymph nodes showed a time-related increase in number of alpha tracks per plutonium source. Electron microscopy showed that the plutonium particles were aggregated in phagolysosomes of macrophages. There was slight clearance of plutonium from the popliteal lymph nodes of dogs monitored for 32 weeks. The clearance of plutonium particles from the popliteal lymph nodes was associated with necrosis of macrophages. The external iliac lymph nodes contained fewer plutonium particles than the popliteal lymph nodes and histopathologic changes were less severe. The superficial inguinal lymph nodes of one dog contained appreciable amounts of ...
Date: August 1, 1973
Creator: Dagle, G.E.
Partner: UNT Libraries Government Documents Department