Digital Commons Network^™

Autoimmunity, Immune Deficiency And Cancer: Multiple Roles Of The Protein Tyrosine Phosphate Shp-1, Melissa J. Joliat

Electronic Theses and Dissertations

One of a large number of mutant mice used in immunological research, the "motheaten" mouse was the first model of a specific protein tyrosine phosphatase deficiency. Mice carrying one of two allelic mutations at the "motheaten" locus have severe systemic autoimmunity and immune dysfunction as a result of mutations in the hematopoietic-cell phosphatase (Hcph) gene, which encodes the protein tyrosine phosphatase SHP-1. Studies using "motheaten" (me/me) and "viable motheaten" (me^v/me^v) mice have increased the understanding of numerous signaling pathways in immune and hematopoietic cells. A number of studies on SHP-1 function …

Reaction-Diffusion Models Of Cancer Dispersion, Kim Yvette Ward

Mathematics & Statistics Theses & Dissertations

The phenomenological modeling of the spatial distribution and temporal evolution of one-dimensional models of cancer dispersion are studied. The models discussed pertain primarily to the transition of a tumor from an initial neoplasm to the dormant avascular state, i.e. just prior to the vascular state, whenever that may occur. Initiating the study is the mathematical analysis of a reaction-diffusion model describing the interaction between cancer cells, normal cells and growth inhibitor. The model leads to several predictions, some of which are supported by experimental data and clinical observations $\lbrack25\rbrack$. We will examine the effects of additional terms on these characteristics. …

Alterations In Calcium Homeostasis And The Insulin-Like Growth Factor Signaling Pathway Induced By Carcinogenic Polycyclic And Halogenated Aromatic Hydrocarbons In Human Mammary Epithelial Cells, Stacey L. Tannheimer

Pharmaceutical Sciences ETDs

Breast cancer is a major health concern for women, with only a small percent of the risk factors currently identified. It has been estimated that environmental factors may contribute to up to 80% of breast cancer cases. Many environmental carcinogens, such as polycyclic and halogenated aromatic hydrocarbons (PAHs and HAHs), are proven mammary carcinogens in animal models. Therefore, these studies were conducted to elucidate potential roles of PAHs and HAHs in alterations in known signaling pathways in human mammary epithelial cells (HMEC). Carcinogenic PAHs have previously been shown to produce sustained alterations in the calcium (Ca2') homeostasis of lymphocytes Therefore, …

The Cellular And Molecular Dynamics Of The Queuosine Modification In Transfer Rna: Definition, Modulation, Deficiencies And Effect Of The Queuosine Modification System, Rana C. Morris

Theses and Dissertations in Biomedical Sciences

The presence of the queuosine modification in the wobble position of tRNA^asn, tRN^asp, tRNA^his, and tRNA^tyr is associated with a decrease in cellular growth rate, an increase in the ability to withstand environmental stress, and differentiation of pleuripotent cells into mature phenotypes. The loss of this normal modification is strongly correlated with neoplastic transformation and tumor progression of a wide variety of cancers.

The "normal" system for formation of the queuosine modification in tRNA was studied in human fibroblast cell cultures and in mouse, rat and human liver tissues. The queuosine modification system …

Identification And Characterization Of Genes Associated With V-Jun Induced Cell Transformation, Martin Toralballa Hadman

Biological Sciences Theses & Dissertations

The v-jun oncogene was initially identified as the causative agent for fibrosarcomas in chickens. Studies show that overexpression of v-Jun proteins transforms chicken embryo fibroblasts (CEF) in vitro, and forms tumors in chickens in vivo. The mechanisms for this are not clearly defined. Conceivably, overexpression of an unregulated transcription factor would cause cell transfonnation by illicit regulation of its target genes. In support of this, we show that in vivo v-Jun complexes exhibit differential binding to in vitro generated AP-1 and 'AP-1 like' target sequences, suggesting that the pattern of target gene expression is altered during cell transformation. …

Hla Typing For Breast Cancer Patients In Egypt, Maha Adly Guindi

Archived Theses and Dissertations

No abstract provided.

The Role Of Small Peptides In Cancer Physiology And Chemotherapy, Bao-Ling Tsay

Theses and Dissertations in Biomedical Sciences

The targeting of proven anticancer drugs specifically to cancer cells would provide a unique opportunity to restrict neoplasms without damaging the cancer patient. The present research utilizes the phenomenon of illicit transport, i.e. the coupling of normally impermeant metabolites to permeant metabolites, in targeting the drug melphalan to mouse Ehrlich ascites tumor cells. The dipeptide beta-alanyl-melphalan was synthesized and tested in vitro for toxicity towards mouse Ehrlich ascites tumor cells, mouse liver cells, and mouse 3T3 embryonic cells. The parent compound, melphalan, was used as a control treatment. In addition, both melphalan and beta-alanyl-melphalan were utilized in in vivo chemotherapeutic …

Studies Of N⁵, N¹⁰-Methylene Tetrahydrofolate Reductase From Porcine Kidney And Mouse L1210-Induced Tumor Tissues, Purification And Interaction With Antifolates, David W. Jayme

Theses and Dissertations

Methylene tetrahydrofolate reductase has been purified 1000-fold from porcine kidney and 400-fold from mouse L1210-induced tumor tissue by classical methods. The enzyme preparations have been demonstrated to be essentially free of contaminating methionine synthetase and serine transhydroxymethylase activity. Studies of the kinetic properties of the kidney and tumor enzymes, with respect to the reverse reaction using N5-methyl tetrahydrofolate as the variable substrate, have indicated Km values of 2.0 and 2.4 x 10-4 M, respectively. Inhibition of this key branch point enzyme in folate metabolism by a number of antimetabolites indicates that several of these antifolate compounds exhibit enzyme inhibition superior …

The External Morphology Of The First Zoeal Stages Of Cancer Magister (Dana), Cancer Antennarius (Stimpson), And Cancer Anthonyi (Rathbun), Robert Dotson Mir

University of the Pacific Theses and Dissertations

The literature dealing with the larva of Pacific Coast brachyuran crabs is slight. The prominent papers, those of Aikawa (1927, 1928, 1929, 1933, 1937), deal with a variety of genera and offer information useful in determin- ing family relationships. A single paper by Hart (1935) also deal with a number of brachyuran larvae found in the Pacific Ocean. None of these papers, however, identifies to species any member of the genus Cancer, although one member, C. magister (Dana) is of considerable economic importance on the pacific coast of North America. In the fall of 1958 an investigation was under taken …