Life Sciences Commons^™

The Effects Of Selenate, Molybdate And Chromate On The Triiodothyronine Induced Enzyme Activity And Mrna Level For Both Fatty Acid Synthase And Malic Enzyme, Yuan Zhu

Masters Theses

In chick embryo hepatocytes in culture, triiodothyronine (T3) stimulates enzyme activity, mRNA level and transcription rate for both fatty acid synthase (FAS) and malic enzyme (ME). Recent evidence has demonstrated the effects of selenate, molybdate and chromate on various physiological processes. Little information, however, is available on the effects of these metal ions on the T3- regulated gene expression for FAS and ME.

In chick embryo hepatocytes incubated in a chemically defined medium, addition of sodium selenate (20 μM) coincident with T3 almost completely inhibited the T3-induced stimulation of FAS and ME activity and accumulation of their respective mRNA's. Neither …

High Performance Liquid Chromatographic Separation Of Different Types Of Collagen, Yongjoo Chung

Chemistry & Biochemistry Theses & Dissertations

The objective of this research was to develop a method for the separation of different types of collagen using a large pore size (100 nm) reversed-phase C-8 column. Three different types of collagen (type I, III, and V) were sufficiently separated on the column using a mobile phase containing water-acetonitrile-trifluoroacetic acid. Collagens found in each HPLC peak were identified using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to assay the column effluents.

Trifluoroacetic acid (TFA) was used as an ion pair reagent. This compound improved the chromatographic profile for these proteins on a reversed-phase column. It was observed that with …

Purification And Characterization Of The Prostate Cancer-Associated Antigen: 7e11-C5, Qi Feng

Theses and Dissertations in Biomedical Sciences

A murine monoclonal antibody (MAb), 7E11-C5, recognizes a prostate organ-specific antigen. Under reducing conditions, the 7E11-C5 antigen exhibited major 100-Kd and minor 70-Kd bands, suggesting that the antigen comprises two peptide chains. The antigen was detected in pooled normal human seminal plasma, xenograft tissue extract of a prostate adenocarcinoma cell line, LNCaP, and tissue extracts of benign prostatic hyperplasia (BPH) and prostate carcinomas, but was not identified in any of the non-prostate tissue extracts tested. Antibodies of the three major prostate-associated antigens (prostatic acid phosphatase (PAP), prostate specific antigen (PSA) and prostate secretory protein (PSP)) were unable to block the …

Molecular Genetics Of Endocrine Induced Regression Of Mouse Leydig Cell Tumors, Milton Rolando Drachenberg

Loma Linda University Electronic Theses, Dissertations & Projects

Chronic estrogen treatment results in malignant Leydig cell tumor formation in genetically susceptible strains of mice. The hypothesis that the mechanism of estrogen induced carcinogenesis includes a gene amplification event was tested using this in vivo endocrine carcinogenesis model. High molecular weight DNA isolated from liver, hyperplastic chryptorchid testes, primary Leydig cell tumors and transplanted tumor lines progressing to estrogen nondependence for growth, was studied using Southern blot analysis and the in-gel renaturation technique to identify amplification of characterized and anonymous sequences. No consistent gene amplification event could be demonstrated either in carcinogenesis or tumor progression to an estrogen nondependent …

Aerotaxis In Halobacterium Halobium, Jemima Clara Lindbeck

Loma Linda University Electronic Theses, Dissertations & Projects

Aerotaxis, previously studied in eubacteria was investigated in the archaebacterium Halobacterium halobium. A quantitative temporal assay for aerotaxis of H. halobium was developed using computer assisted motion analysis. Aerotaxis was most pronounced in early log phase cultures. Peak aerotaxis was found to coincide with peak respiration consistent with a model in which respiration is required for aerotaxis. In a spatial assay a mutant strain lacking the proton motive force (pmf)-generating pigments, bacteriorhodopsin (bR) and halorhodopsin (hR), exhibited enhanced aerotaxis bands relative to the bR⁺hR⁺ parent. The enhanced aerotaxis in the mutant cells was not due solely to …

Mouse Mast Cell Proteases: Induction, Molecular Cloning, And Characterization, Wei Chu

Electronic Theses and Dissertations

Tryptase, a mast cell-specific serine protease with trypsin-like specificity, has been identified in a mouse mast cell line (ABFTL-6) based on it's enzymatic activity, inhibition properties, and cross-reactivity to a human mast cell tryptase antibody. The effects of fibroblast-conditioned medium and sodium butyrate on ABFTL-6 mast cell differentiation and tryptase expression have been examined. ABFTL-6 mouse mast cells undergo phenotypic changes upon culturing in media supplemented with fibroblast-conditioned media at 50% or 1 mM sodium butyrate. The induced cells increased in size, had larger and more metachromatic cytoplasmic granules, and increased their total cellular protein about four-fold. Tryptase activity increased …

Nitrogen Dioxide Reaction With Proteins: Evidence For Peptide Bond Cleavage At Lysine Residues, Darryl B. Hood

Electronic Theses and Dissertations

Nitrogen dioxide (NO$\sb2$), an air pollutant produced by burning fossil fuels and a component of cigarette smoke, is thought to contribute to the pathogenesis of pulmonary diseases, such as emphysema. To gain information on the mechanism by which NO$\sb2$ damages the lung, in vitro exposures of $\alpha\sb1$-proteinase inhibitor ($\alpha\sb1$-PI), elastin, bovine serum albumin (BSA), human serum albumin (HSA) and synthetic poly-L-lysine were performed. A genetic deficiency of $\alpha\sb1$-PI predisposes humans to emphysema and NO$\sb2$ has been hypothesized to damage $\alpha\sb1$-PI, which would leave proteases such as human neutrophil elastase, (HNE) free to attack lung structural proteins. The ability of $\alpha\sb1$-PI …

Metabolism Of Arachidonate-Containing Phospholipid Molecular Species In The Murine Macrophage-Like Cell Line, P388d1, Crystal R. Waites

Electronic Theses and Dissertations

Glycerophospholipids of mammalian cells exist as chemically diverse structures with various fatty acids at the sn-1 and sn-2 positions. Arachidonic acid, a polyunsaturated fatty acid, which may be converted to biologically active eicosanoids such as prostaglandins, thromboxanes, and leukotrienes, is found predominantly in the sn-2 position of glycerophospholipids. The purpose of this study was to examine, at the level of the individual molecular species, the incorporation of arachidonate into phospholipids and its release from phospholipids during stimulation. In this way, the specificity of the enzymes controlling arachidonate metabolism could be examined in order to clarify the processes that control the …

The Role Of Queuine Deficient Trna In Translational Control, Kathryn Lenore Hart

Theses and Dissertations in Biomedical Sciences

The purpose of this research was to study the effect of the level of tRNA modification with respect to queuine on translational efficiency. Transfer RNA from neoplastic cells is generally deficient with regard to certain hypermodified nucleosides found in normal cells. The hypothesis that was examined is whether or not the altered efficiency of translation can be correlated to the presence of queuine hypomodified tRNA. The loss of queuine in the anticodon may change the interaction of the tRNA's anticodon with its codon. Therefore, the translational complex may stall looking for a rare tRNA, or the stability of the complex …

A Biochemical Study Of Gossypol And Lactate Dehydrogenase X Binary Interactions, Patricia Brown Ravenell

Theses and Dissertations in Biomedical Sciences

The goal of this project was to study the mechanism of action of gossypol through its (a) binary interaction with native and trypsin digested lactate dehydrogenase-X (LD-X), a sperm-specific isozyme, and (b) its binding in vitro in primary cultures of spermatogenic cells. Mouse LD-X was cleaved with trypsin before and after treatment with gossypol. This was followed by high performance chromatography (HPLC) separation of the LD-X tryptic peptide fragments to observed alterations in separation patterns as indicators of intramolecular disturbance in the enzyme molecule. Definite alterations in peptide fragment peaks were observed in the presence of gossypol and suggest conformational …

The Study Of Natural Product(S) From Opsanus Tau (Linnaeus), The Oyster Toadfish, Miki Taira

Chemistry & Biochemistry Theses & Dissertations

Opsanus tau (Linnaeus), the Oyster toadfish, commonly inhabits the Chesapeake Bay. The Oyster toadfish has been categorized as a venomous and/or ichthyotoxic fish; however, chemical studies to substantiate these claims have not been forthcoming.

The oyster toadfish has dorsal and opercular spines which are believed to secrete a venom(s). Based on our findings, the oyster toadfish does not secrete venom(s) from these spines.

The oyster toadfish secretes large amounts of a mucus when it is irritated. 3-Octanone was believed to be the major ichthyotoxic component of the mucus from the oyster toadfish. Based on our investigation, 3-octanone is present only …

Molecular Mechanism Of The Stimulation Of Alkaline Phosphatase Activity In Human Bone Cells By 1,25(Oh)2 D3, Eru Kyeyune-Nyombi

Loma Linda University Electronic Theses, Dissertations & Projects

To facilitate this study an in vitro human model system was established that exhibited many aspects of normal osteoblasts. The human osteosarcoma cell line (TE85 cells) expressed a skeletal alkaline phosphatase activity (an accepted bone cell differentiation marker) which was stimulated by 1,25(OH)₂D₃ (a potent differentiating agent), under serum-free conditions in a dose-dependent, time-dependent, and cell density-dependent manner. Cytochemical analysis of the stimulation of ALP activity by 1,25(OH)₂D₃ showed that 1,25(OH)₂D₃ increased the number of TE85 cells that expressed detectable ALP activity, suggesting that 1,25(OH)₂D₃ promoted the process …

Immunological Identification Of A Centrin Homologue In The Red Alga Gracilaria Tikvahiae, Christopher Lee Dassler

Dissertations, Theses, and Masters Projects

No abstract provided.

Monooxygenase Induction And Lethality As Endpoints In Aquatic Toxicology, Daniel W. Sved

Dissertations, Theses, and Masters Projects

Spot, Leiostomus xanthurus, were exposed to suspended sediments (&\approx&20 mg/L) contaminated with polycyclic aromatic hydrocarbons (PAH) in a laboratory flow-through system to evaluate the applicability of hepatic ethoxyresorufin O-deethylase (EROD) induction as an indicator of PAH exposure. PAH sources tested were coal-tar creosote (CTC), a low molecular weight fraction of creosote (LMWF), and a high molecular weight fraction of creosote (HMWF). A standard 96-h acute toxicity test was conducted to ensure that PAH concentrations tested in induction studies were sub-acutely toxic. The 96-h LC50 for spot was 1740 &\mu&g PAH/L (95% confidence interval = 1480-2060 &\mu&g PAH/L). The lowest concentration …

Evaluation Of A Technique To Quantify Lipids In Bivalve Larvae Crassostrea Virginica Gmelin, Using Nile Red And Epiflourescence Microscopy, Laura Liliana Castell Perez

Dissertations, Theses, and Masters Projects

No abstract provided.