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A High-fat Meal Alters Post-prandial mRNA Expression of SIRT1, SIRT4, and SIRT6

Description: Sirtuins (SIRT) regulate the transcription of various genes involved in the development of diet-induced obesity and chronic disease; however, it is unknown how they change acutely following a high-fat meal. The purpose of this study was to determine the effect of a high-fat meal (65% kcals/d; 85% fat recommendation), on SIRT1-7 mRNA expression in blood leukocytes at 1, 3, and 5-h post-prandial. Men and women (N=24) reported to the lab following an overnight fast (>12H). Total RNA was isolated and reverse transcribed prior to using a Taqman qPCR technique with 18S rRNA as a normalizer to determine SIRT1-7 mRNA expression. An additional aliquot of serum was used to measure triglycerides. Data was analyzed using a RM ANOVA with P<0.05. Triglycerides (P<0.001; 124%) peaked at 3-h. SIRT 1 (P=0.004; 70%), and SIRT 6 (P=0.017; 53%) decreased expression at 3-h. SIRT4 (P=0.024) peaked at 5H relative to baseline (70%) and 3-h (68%). To our knowledge, this is the first study to report that consumption of a high-fat meal transiently alters SIRT mRNA expression consistent in a pattern that mirrors changes in serum triglycerides. Decrease in expression of SIRT1 and SIRT6 combined with an increased SIRT4 would be consistent with an increase in metabolic disease risk if maintained on a chronic basis.
Date: December 2015
Creator: Best Sampson, Jill Nicole
Partner: UNT Libraries

The changes in the blood of humans chronically exposed to low level gamma radiation

Description: Ten individuals received an average of 0.211 roentgens of gamma radiation per week for a 77 period week (December 1946-June 1948) for a total average dose of 16.21 roentgens. During this period these 10 men carried out an experiment involving materials which emit gamma radiation and were monitored by daily film badges. The radiation delivered during a week was received in a five day work week and usually they received approximately one-half of their weekly dosage during one of the five days. A significant fall in total white blood count and absolute neutrophil and lymphocytes count was observed during the 77 week period. The degree of fall in counts would not have been predicted from experimental irradiation in animals and so other unknown factors may have been causal agents. It is suggested that hematological and exposure data from other laboratories be analyzed statistically to confirm or disprove the effect of such low- dosages of ionizing radiation on humans.
Date: December 31, 1948
Creator: Knowlton, N.P. Jr.
Partner: UNT Libraries Government Documents Department

Transgenic Mouse Model of Chronic Beryllium Disease

Description: Animal models provide powerful tools for dissecting dose-response relationships and pathogenic mechanisms and for testing new treatment paradigms. Mechanistic research on beryllium exposure-disease relationships is severely limited by a general inability to develop a sufficient chronic beryllium disease animal model. Discovery of the Human Leukocyte Antigen (HLA) - DPB1Glu69 genetic susceptibility component of chronic beryllium disease permitted the addition of this human beryllium antigen presentation molecule to an animal genome which may permit development of a better animal model for chronic beryllium disease. Using FVB/N inbred mice, Drs. Rubin and Zhu, successfully produced three strains of HLA-DPB1 Glu 69 transgenic mice. Each mouse strain contains a haplotype of the HLA-DPB1 Glu 69 gene that confers a different magnitude of odds ratio (OR) of risk for chronic beryllium disease: HLA-DPB1*0401 (OR = 0.2), HLA-DPB1*0201 (OR = 15), HLA-DPB1*1701 (OR = 240). In addition, Drs. Rubin and Zhu developed transgenic mice with the human CD4 gene to permit better transmission of signals between T cells and antigen presenting cells. This project has maintained the colonies of these transgenic mice and tested the functionality of the human transgenes.
Date: May 26, 2009
Creator: Gordon, Terry
Partner: UNT Libraries Government Documents Department

Tumor Engineering: The Other Face of Tissue Engineering

Description: Advances in tissue engineering have been accomplished for years by employing biomimetic strategies to provide cells with aspects of their original microenvironment necessary to reconstitute a unit of both form and function for a given tissue.We believe that the most critical hallmark of cancer is loss of integration of architecture and function; thus, it stands to reason that similar strategies could be employed to understand tumor biology. In this commentary, we discuss work contributed by Fischbach-Teschl and colleagues to this special issue of Tissue Engineering in the context of 'tumor engineering', that is, the construction of complex cell culture models that recapitulate aspects of the in vivo tumor microenvironment to study the dynamics of tumor development, progression, and therapy on multiple scales. We provide examples of fundamental questions that could be answered by developing such models, and encourage the continued collaboration between physical scientists and life scientists not only for regenerative purposes, but also to unravel the complexity that is the tumor microenvironment. In 1993, Vacanti and Langer cast a spotlight on the growing gap between patients in need of organ transplants and the amount of available donor organs; they reaffirmed that tissue engineering could eventually address this problem by 'applying principles of engineering and the life sciences toward the development of biological substitutes. Mortality figures and direct health care costs for cancer patients rival those of patients who experience organ failure. Cancer is the second leading cause of death in the United States (Source: American Cancer Society) and it is estimated that direct medical costs for cancer patients approach $100B yearly in the United States alone (Source: National Cancer Institute). In addition, any promising therapy that emerges from the laboratory costs roughly $1.7B to take from bench to bedside. Whereas we have indeed waged war on cancer, the training ...
Date: March 9, 2010
Creator: Ghajar, Cyrus M & Bissell, Mina J
Partner: UNT Libraries Government Documents Department

The antibody approach of labeling blood cells

Description: Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.
Date: January 1, 1991
Creator: Srivastava, S.C.
Partner: UNT Libraries Government Documents Department

Labeling of blood cells with /sup 99m/Tc

Description: Erythrocytes, leukocytes, and tumor cells were labeled with /sup 99m/Tc to take advantage of the ideal physical properties of /sup 99m/Tc. Clinical studies indicate that labeled erythrocytes can be used to obtain improved vascular and splenic imaging as well as reliable red cell volumes. The erythrocytes have been labeled with and without the use of an added reducing agent. Two methods of adding the reducing agent stannous chloride have been proposed which differ in the order of addition of the stannous ion and the pertechnetate. The preliminary reports of labeling of leukocytes and tumor cells offer hope that further development will result in truly specific radiopharmaceuticals. (auth)
Date: January 1, 1974
Creator: Eckelman, W.C.; Smith, T.D. & Richards, P.
Partner: UNT Libraries Government Documents Department

Biochemical studies relating to the effects of radiation and metals

Description: Various biochemical effects of radiation have been studied in 10 patients given total body x-ray in total doses of 75 to 310 r (skin), in 5 patients given 20 to 36 mc. P{sup 32}, and in 5 project personnel accidentally exposed to excessive doses of external radiations. Similar studies have also been made of several hundred Plutonium Project personnel exposed in most instances to relatively small amounts of uranium, lead and other metals, and to chemicals and radioactive sources. These studies included the investigation of liver function, of white blood cell chemistry, and of various urinary constituents such as coproporphyrin, urorosein and other pigments, urobilinogen, ``corticosteroid-like`` substances, catalase, and uranium. Definitely excessive exposures resulted in various abnormalities in the above tests. With the exception of urinary uranium analysis none of them are specific in indicating overexposure to either radiation, metals, or chemicals. When interpreted in the light of the exposure and medical history, however, it is felt that they may aid in the clinical interpretation of relatively marked overexposure at least. In addition, they may afford further insight into the nature of radiation effects. The literature on the biochemical effects of radiation is reviewed briefly, and certain suggestions are offered regarding future investigations in this field.
Date: July 1, 1947
Creator: Schwartz, S.
Partner: UNT Libraries Government Documents Department

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 gene expression in a panel of normal and tumor cells untreated or treated with ionizing radiation or H{sub 2}O{sub 2}. Treatment with radiation or H{sub 2}O{sub 2} produced a varied response, from some reduction to an increase of more than an order of magnitude in the steady-state level of c-jun mRNA. These data indicate that although induction of c-jun may be a common response to ionizing radiation and H{sub 2}O{sub 2}, this response was reduced or absent in some cell types.
Date: June 1, 1993
Creator: Collart, F.R.; Horio, M. & Huberman, E.
Partner: UNT Libraries Government Documents Department

University of California, Los Angeles Campus School of Medicine Atomic Energy Project quarterly progress report for period ending March 31, 1952

Description: The fifteenth quarterly report being submitted for Contract No. AT04-1-GEN-12 is issued in accordance with Service Request Number 1 except for the report of the Alamogordo Section, Code 91810, which is submitted in accordance with the provisions of Service Request Number 2. Work is in progress on continuing existing projects. In addition, new projects have been initiated including the Kinetics and Mechanism of Protein Denaturation (10018); The Effect of Irradiation on the Constituents of Embryonic Serum (30033); and The Use of Controlled Atmospheres for Spectrographic Excitation Sources (40053). Many of the Project units are either wholly or partially completed and the following initial reports are available: Identification of Ferritin in Blood of Dogs Subjected to Radiation from an Atomic Detonation (UCLA-180); The Nutritional Value of Intravenous Tapioca Dextrin in Normal and Irradiated Rabbits (UCLA-181); The-Decarboxylation and Reconstitution of Linoleic Acid (UCLA-183); Preparation and Properties of Thymus Nucleic Acid (UCLA-184); The Radiation Chemistry of Cysteine Solutions Part II. (a) The Action of Sulfite on the Irradiated Solutions; (b) The Effect on Cystine (UCLA-185); A Revolving Specimen Stage for the Electron Microscope (UCLA-178); An Automatic Geiger-Mueller Tube Tester (UCLA-186); The Value of Gamma Radiation Dosimetry in Atomic Warfare Including a Discussion of Practical Dosage Ranges (UCLA-187); and A New Plastic Tape Film Badge Holder (UCLA-189). Two additional reports were issued; one by Dr. Wilbur Selle entitled Attempts to Alter the Response to Ionizing Radiations from the School of Medicine, UCLA (UCLA-176), and two, a restricted distribution report from the Alamogordo Section entitled Field Observations and Preliminary Field Data Obtained by the UCLA Survey Group on Operation Jangle, November 1951 (UCLA-182).
Date: April 10, 1952
Creator: Warren, S.L.
Partner: UNT Libraries Government Documents Department

Sorting of a murine granulocytic progenitor cell by use of laser light scattering measurements

Description: Multiangle light-scattering measurements provided a useful basis for analysis and separation of bone marrow cell suspensions. Six to eight major subpopulations of cells could be distinguished by simultaneous measurements of forward and 90/sup 0/ light-scattering, which is more than with any other known cell separation method. The observation that CFU-c were found in only one of these subpopulations confirms the conclusions that CFU-c are a homogeneous population of a single cell type.
Date: January 1, 1977
Creator: Visser, J.W.M.; Cram, L.S.; Martin, J.C.; Salzman, G.C. & Price, B.J.
Partner: UNT Libraries Government Documents Department

Kinetics of reversible-sequestration of leukocytes by the isolated perfused rat lung

Description: The kinetics and morphology of sequestration and margination of rat leukocytes were studied using an isolated perfused and ventilated rat lung preparation. Whole rat blood, bone marrow suspension, or leukocyte suspensions, were used to perfuse the isolated rat lung. The lung was also perfused with latex particle suspensions and the passage of particles through the lung capillaries was studied. When a leukocyte suspension was perfused through the lung in the single-pass mode, the rate of sequestration decreased as more cells were perfused. In contrast, latex particles of a size comparable to that of leukocytes were totally stopped by the lung. When the leukocyte suspension was recirculated through the lung, cells were rapidly removed from circulation until a steady state was reached, after which no net removal of cells by the lung occurred. These results indicate that leukocytes are reversibly sequestered from circulation. The sequestered cells marginated and attached to the luminal surface of the endothelium of post-capillary venules and veins. A mathematical model was developed based on the assumption that the attachment and detachment of leukocytes to blood vessel walls follows first-order kinetics. The model correctly predicts the following characteristics of the system: (a) the kinetics of the sequestration of leukocytes by the lung; (b) the existence of a steady state when a suspension of leukocytes is recirculated through the lung; and (c) the independence of the fraction of cells remaining in circulation from the starting concentration for all values of starting concentration. (ERB)
Date: August 1, 1980
Creator: Goliaei, B.
Partner: UNT Libraries Government Documents Department

Flow cytometric measurements of cell surface phenomena

Description: The study of cell surface phenomena by flow cytometry has been pursued by several groups. These studies have produced new insights into a variety of areas of biology. However, the capabilities of flow systems have not been fully exploited. A technique for discriminating between surface and volume fluorescence is proposed along with a method to quantitate cap formation in lymphocytes.
Date: January 1, 1979
Creator: Jett, J.H.
Partner: UNT Libraries Government Documents Department

Approaches to the preservation of human granulocytes by freezing

Description: Because of its simplicity, the FDA assay can be used effectively as a screening test to eliminate procedures and treatments that are damaging to cells. In this context, a number of conclusions can be drawn from the data presented: (1) Exposure to 1 and 2 M glycerol at room temperature damages human granulocytes in a few minutes. Reducing the exposure temperature to 0/sup 0/C reduces the amount of injury substantially. (2) Human granulocytes respond to freezing and thawing in a manner typical of many mammalian cells in that they exhibit a maximum in survival at an optimum cooling rate slightly above 1/sup 0/C/min when combined with rapid warming. The use of rapid warming and a high (2 M) concentration of glycerol reduces the dependence of survival on cooling rate by broadening the range of rates over which survival is relatively high. (3) Human granulocytes show some sensitivity to dilution stresses since survival depends somewhat on the concentration of glycerol used and the severity of the dilution procedure. The reasons for the sharp decrease in cell viability following incubation of frozen-thawed granulocytes at 37/sup 0/C are not known. One possibility is that the phosphate buffered saline suspending medium used is not suitable for incubation at 37/sup 0/C. A second possibility is that some cell injury is not expressed at 0/sup 0/C and remains undetected by the FDA assay until the cells are incubated at 37/sup 0/C. There is also the possibility that lysosomal enzymes released by a few damaged cells in a sample will cause additional damage in other cells at 37/sup 0/C.
Date: January 1, 1979
Creator: Frim, J & Mazur, P
Partner: UNT Libraries Government Documents Department

Models for the interaction between cells of the immune system

Description: The following topics are discussed: mathematical models of cell-to-cell interactions; role of cell-to-cell contacts in regulating immune responses; cell-to-cell binding; the strength of specific bonds; rate of bond formation; and effects of binding on cell behavior. It is concluded that receptor accumulations are to be expected in areas of cell--cell contact. Gross alterations in membrane properties in these contact caps may result. (HLW)
Date: January 1, 1978
Creator: Bell, G.I.
Partner: UNT Libraries Government Documents Department

Bovine lymphocytic leukemia: studies of etiology, pathogenesis, and mode of transmission. Progress report No. 19, June 1978-June 1979

Description: Bovine leukemia is believed to be caused by an oncogenic RNA virus designated bovine leukemia virus (BLV). The presence of BLV particles in lymphocyte cultures from leukemic cattle and cattle with a persistent lymphocytosis has been consistentily demonstrated. Concentrated, cell free, BLV preparations were used to inoculate 12 late stage bovine fetuses (in utero) and two newborn calves. Current studies involve extensive monitoring of these inoculated animals to detect precancerous changes and obtain a detailed description of the events preceding the development of lymphosarcoma. Ongoing monitoring studies will provide a complete record of all changes in the various leukemia associated parameters. We will then be able to detail when, in what sequence, and to what extent each parameter changes in the course of lymphosarcoma development. Fourteen animals were successfully inoculated during the study. Eleven remain alive, and comprise the current monitoring program. All eleven of these animals are definitely infected with BLV, and in nine the infection has substantially progressed with respect to the parameters being monitored. In addition to transmission and monitoring studies, various lymphocyte subpopulations were examined to determine which cell type(s) are involved in the pathogenesis of bovine lymphosarcoma. These studies have conclusively established that B-lymphocytes are the target cells for BLV infection and that they carry the morphologic nuclear abnormality associated with this disease.
Date: July 1, 1979
Creator: Sorensen, D.K.
Partner: UNT Libraries Government Documents Department

Applications of optimal control theory to immunology

Description: When an animal is challenged by a foreign substance which promotes an immune response, certain cells within the animal begin dividing, secreting antibody molecules, and differentiating into more specialized cell types. Optimal control theory is applied to ascertain the best strategy available to the immune system in allocating its cells. By examining a variety of mathematical models for cell populations and their antibody production, it is found that the optimal strategy of bang-bang control is robust. Experimental evidence which supports such strategies is also discussed.
Date: January 1, 1977
Creator: Perelson, A.S.
Partner: UNT Libraries Government Documents Department

(In vivo mutagenicity and clastogenicity of ionizing radiation in nuclear medicine)

Description: The overall goals of our research remains to investigate the mutagenic and clastogenic effects of exposure to low levels of ionizing radiation in human lymphocytes. We are studying hospital patients referred to a nuclear medicine department for diagnostic cardiac imaging and nuclear medicine technologists who administer radionuclides.
Date: January 1, 1989
Partner: UNT Libraries Government Documents Department