Life Sciences Commons^™

Axogial Communication Mediated By Soluble Neuregulin-1 And Bdnf, Zhenzhong Ma

Wayne State University Dissertations

During peripheral nervous system development, successful communication between axons and glial cells including Schwann cells in peripheral nervous system and oligodendrocytes in central nervous system, is required for the proper functions of both neurons and glia. Three types of alternatively-spliced proteins belonging to the neuregulin1 (NRG1) gene family of growth and differentiation factors are essential for Schwann cell survival and peripheral nerve development. While membrane-bound NRG1 forms (type III) has been strongly implicated in the regulation of myelination process at late stage of Schwann cell development, little is known about the role of soluble, heparin-binding forms of NRG1 (type I/II) …

Mechanisms Of Persistent Translation Arrest Following Global Brain Ischemia And Reperfusion, Jill Theresa Jamison

Wayne State University Dissertations

ABSTRACT

MECHANISMS OF PERSISTENT TRANSLATION ARREST FOLLOWING GLOBAL BRAIN ISCHEMIA and REPERFUSION

by

JILL T. JAMISON

December 2011

Advisor: Donald J. DeGracia, Ph.D.

Major: Physiology

Degree: Doctor of Philosophy

The information presented here studies the mechanisms that underlie persistent translation arrest (TA) following global brain ischemia and reperfusion (I/R). To summarize the main findings I have discovered a new mechanism for prolonged post-ischemic TA that correlated exactly with in vivo translation rates and correlated precisely with cell outcome. Through the extensive colocalization studies, my results indicate that the mRNA granules are ribonomic structures involved with mRNA regulation. This finding is …

The Impact Of Folate Deficiency On The Base Excision Repair Pathway: Analysis Of Enzyme Coordination In Response To Dna Damage And Imbalanced Repair, Amanda Pilling

Wayne State University Dissertations

The condition of folate deficiency has been implicated in carcinogenesis, with the strongest evidence formulated in colon cancer. The role of folate in DNA repair, DNA synthesis and methylation reactions renders this nutrient an valuable target for studying the onset and progression of cancer. Using molecular techniques to determine gene and protein expression, enzyme activity and methylation status elucidates the mechanism of DNA repair and damage in folic acid deficient animals in response to carcinogen. The findings presented in this study indicate failure to remove and repair damage in the condition of folate deficiency and suggest that the accumulation of …

Estrogen Sulfotransferase (Sult1e1) Expression And Function In Mcf10a-Series Breast Epithelial Cells: Role As A Modifier Of Breast Carcinogenesis And Regulation By Proliferation State, Jiaqi Fu

Wayne State University Dissertations

Estrogen sulfotransferase (SULT1E1) catalyzes the sulfonation of estrogens, which limits estrogen mitogenicity. TaqMan Gene Expression assays were used to profile the mRNA expression of estrogen receptor (ERα and ERβ) and estrogen metabolism enzymes including cytosolic sulfotransferases (SULT1E1, SULT1A1, SULT2A1, and SULT2B1), steroid sulfatase (STS), aromatase (CYP19), 17β-hydroxysteroid dehydrogenases (17βHSD1 and 2), CYP1B1, and catechol-O-methyltransferase (COMT) in an MCF10A-derived lineage cell culture model for basal-like human breast cancer progression and in ERα-positive luminal MCF7 breast cancer cells. Low levels of ERα and ERβ mRNA were present in MCF10A-derived cell lines. SULT1E1 mRNA was more abundant in confluent relative to subconfluent MCF10A …

Hedgehog Signaling: A Potential Therapeutic Target For Non-Small Cell Lung Cancer, Ma'in Yehya Maitah

Wayne State University Dissertations

The American Cancer Society estimated that 222,520 Americans were diagnosed with lung cancer and 157,300 died of lung cancer in 2010 (Jemal et al. 2009, 225-249;Jemal et al. 2011, 69-90). The clinical outcome of patients diagnosed with non-small cell lung cancer (NSCLC), the major lung cancer sub-types, is very poor, which calls for innovative research for finding novel therapeutic targets and agents for better treatment outcome.

Emerging evidences have suggested that a phenomenon called Epithelial-to-Mesenchymal Transition (EMT), which shares similar molecular characteristics with cancer stem-like cells, contributes to lung cancer treatment failure. In view of the fact that EMT process …

Mechanisms Of Translation Arrest Following Focal Brain Ischemia, Monique K. Lewis

Wayne State University Dissertations

MECHANISMS OF TRANSLATION ARREST FOLLOWING FOCAL BRAIN

ISCHEMIA

by

MONIQUE K. LEWIS

August 2011

Advisor: Dr. Donald DeGracia

Major: Physiology

Degree: Doctor of Philosophy

The loss of blood flow to the brain is termed ischemia and the subsequent resumption of blood flow is termed reperfusion. Brain ischemia and reperfusion (I/R) occurs primarily following resuscitation from cardiac arrest and stroke and presents one of the most significant clinical challenges. At present, there are no clinically effective pharmacologic interventions to halt brain damage following I/R. The major Aim of this dissertation will be to investigate possible mechanisms involved in neuron death following …

The Potential Role Of Innate Immunity In The Pathogenesis Of Post-Operative Adhesions, Jennell White

Wayne State University Dissertations

Post-operative adhesion development occurs in the vast majority of patients following abdominal surgery and is a natural occurrence of peritoneal-wound healing. These fibrous bands may form within the first 5-7 days post-surgery and have the ability to cause a distortion in the normal anatomical positioning of abdominal organs. Consequently, adhesions are major contributors to small bowel obstruction, infertility, and severe pelvic and abdominal pain. Physiological processes responsible for adhesion formation remain obscure though it is believed to involve cell migration, proliferation, and differentiation of several cell types including mesothelial cells, fibroblasts, and inflammatory and immune cells. Substances released from these …

Human Trophoblast Survival And Invasion In The Developing Placenta: Autocrine Regulation By Hbegf, Philip Jessmon

Wayne State University Dissertations

HBEGF is a multifunctional protein in early pregnancy that induces cytotrophoblast (CTB) cell differentiation to an invasive phenotype, protects against apoptosis, and is involved in an autocrine signaling mechanism that leads to its own protein synthesis. CTBs exist in a low O₂ environment during the first 10 weeks of implantation, during which they invade the decidualized uterine stroma. Inhibitors of intracellular signaling pathways demonstrated that at 20% O₂ HBEGF induces an increase in cell migration through the ERK, MAPK14, JNK, or PIK3 pathways downstream of signaling through its ERBB receptors. Also downstream of these four pathways, HBEGF induces …

Effect Of Dimethylarginine Dimethylaminohydrolase In The Development Of Salt Sensitivity, Samar Abdulla Nasser

Wayne State University Dissertations

Salt sensitivity is associated with a rise in blood pressure (BP) occurring during sodium loading and/or a fall in BP during sodium restriction that exceeds random fluctuations in BP. Salt sensitivity is more common in African American than Caucasian hypertensives and is also present, in normotensive African Americans. The mechanism or mechanisms resulting in salt-sensitive hypertension are multiple and include both activation of the renin angiotensin system via increases in angiotensin II and reductions in the endogenous vasodilator, nitric oxide (NO). An important means of NO downregulation is through asymmetric dimethylarginine (ADMA), an endogenous NO inhibitor, which is largely metabolized …

The Role Of The Sparc Acidic Domain And Egf-Like Module In Glioma Migration, Invasion, And Signaling, Heather M. Mcclung

Wayne State University Dissertations

THE ROLE OF THE SPARC ACIDIC DOMAIN AND EGF-LIKE MODULE IN GLIOMA MIGRATION, INVASION, AND SIGNALING

HEATHER M. MCCLUNG

Advisor: Sandra A. Rempel, Ph.D.

Major: Pharmacology

Degree: Doctor of Philosophy

We have previously shown that Secreted Protein Acidic and Rich in Cysteine (SPARC) is upregulated in all astrocytoma grades and increases tumor cell migration and invasion. It is thought that different domains within the protein may regulate SPARC functions, suggesting domain-specific targeting to inhibit invasion. To enhance our understanding of SPARC-mediated invasion, we first confirm, at the protein level, our previous cDNA array results, that SPARC increases expression of the …

Frazzled And Abelson Interact To Regulate The Actin Cytoskeleton In Drosophila, Bridget Elsa Varughese

Wayne State University Dissertations

Guidance receptors such as Frazzled affect cell shape and motility by directly or indirectly modulating the cytoskeleton. Fra is particularly needed for the formation of the posterior commissures in a developing Drosophila embryo. The cytoplasmic tyrosine kinase, Abelson Kinase (Abl) enhances the loss of commissures observed in fra mutant. Abl physically interacts with Frazzled to help guide commissural axons across the midline. Furthermore, the loss of commissural axons is only seen when the actin dynamics are perturbed. Abl is also known to regulate actin-dependent processes underlying formation of filopodia, microspikes and membrane ruffles. So, we established a Drosophila S2 cell …