Medicine and Health Sciences Commons^™

Longitudinal Extension Of Primary Afferents Is Regulated By Spingosine 1-Phosphate Receptors And Tyrosine Kinase Receptor B In The Embryonic Spinal Cord Via A Brain Derived Neurotrophic Factor Related Mechanism, Michelle Mcnamara

Graduate College Dissertations and Theses

Primary sensory afferent outgrowth within the developing longitudinal pathway of the spinal cord is important for intrasegmental and intersegmental communication that underlies coordination and development of reflexes and contributes to sensory perception. The endogenous mechanisms that regulate primary sensory afferent extension are the primary focus of this dissertation.

This dissertation tested the hypothesis that primary sensory afferent extension in the longitudinal pathway is regulated by sphingosine 1-phosphate type 1 receptor (S1P1R) and tyrosine kinase receptor B (TrkB) through a brain derived neurotrophic factor (BDNF) related mechanism. To test this hypothesis we used embryonic day five (E5) chicken embryos, as this …

Mechanisms Of Seizure During Pregnancy And Preeclampsia, Abbie Chapman Johnson

Graduate College Dissertations and Theses

Eclampsia is defined as de novo seizure in a woman with the hypertensive complication of pregnancy known as preeclampsia (PE), and is a leading cause of maternal and fetal morbidity and mortality worldwide. The pathogenesis of eclamptic seizure remains unknown, but is considered a form of hypertensive encephalopathy where an acute rise in blood pressure causes loss of cerebral blood flow (CBF) autoregulation and hyperperfusion of the brain that results in vasogenic edema formation and subsequent seizure. However, eclamptic seizure can occur during seemingly uncomplicated pregnancies, in the absence of hypertension and PE, suggesting that normal pregnancy may predispose the …

Transient Ischemic Attack (Tia) Guideline Knowledge And Perceived Barriers To Implementation Amongst Emergency Department Health Care Providers In A Rural State, Christopher T. Ingvoldstad

Graduate College Dissertations and Theses

Transient Ischemic Attack (TIA) is a prominent risk factor for subsequent stroke, and its associated morbidity, mortality, and health care costs. Studies have demonstrated up to 80% reductions in subsequent stroke rate with prompt, optimized protocols for rapid TIA evaluation and treatment. National Stroke Association (NSA) and American Heart Association (AHA) guidelines have recommended institution of protocols assuring timely completion of the recommended testing, and evaluation by a stroke expert within 48 hours. However, limited literature exists on the implementation of guideline-based care in rural regions, and the few studies related to TIA suggest that barriers including difficulty accessing services …

Ubiquitin Ligase Trim32 And Chloride-Sensitive Wnk1 As Regulators Of Potassium Channels In The Brain, Eugene Miler Cilento

Graduate College Dissertations and Theses

The voltage-gated potassium channel Kv1.2 impacts membrane potential and therefore excitability of neurons. Expression of Kv1.2 at the plasma membrane (PM) is critical for channel function, and altering Kv1.2 at the PM is one way to affect membrane excitability. Such is the case in the cerebellum, a portion of the brain with dense Kv1.2 expression, where modulation of Kv1.2 at the PM can impact electrical activity of neurons and ultimately cerebellum-dependent learning. Modulation of Kv1.2 at the PM can occur through endocytic trafficking of the channel; however mechanisms behind this process in the brain remain to be defined.

The goal …

Glycogen Synthase Kinase-3Β: An Investigation Of The Novel Serine 389 Phosphorylation Site, Brendan Deegan Hare

Graduate College Dissertations and Theses

Stress associated psychiatric disorders such as depression, anxiety, and post-traumatic stress disorder affect a large proportion of the population. Reductions in the complexity of neuronal morphology and reduced neurogenesis are commonly observed outcomes following stress exposure in rodent models and may represent a mechanism for the reduced brain volume in stress sensitive regions such as the hippocampus observed in individuals diagnosed with stress associated disorders. Multiple lines of evidence suggest that glycogen synthase kinase (GSK)-B may play a role in the neurodegenerative phenotype observed following stress exposure. GSK3B is atypical in that it is inhibited by phosphorylation. This inhibitory phosphorylation …

Traumatic Brain Injury Causes Endothelial Dysfunction In Mesenteric Arteries 24 Hrs After Injury, Ivette Ariela Nunez

Graduate College Dissertations and Theses

Traumatic brain injury (TBI) is the most frequent cause of death in children and young adults in the United States. Besides emergency neurosurgical procedures, there are few medical treatment options to improve recovery in people who have experienced a TBI. Management of patients who survive TBI is complicated by both central nervous system and peripheral systemic effects. The pathophysiology of systemic inflammation and coagulopathy following TBI has been attributed to trauma-induced endothelial cell dysfunction; however, there is little knowledge of the mechanisms by which trauma might impact the functions of the vascular endothelium at sites remote from the injury. The …

Mechanoregulation Of Leading Edge Pka Activity During Ovarian Cancer Cell Migration, Andrew J. Mckenzie

Graduate College Dissertations and Theses

Ovarian cancer is the deadliest of all the gynecologic cancers and is known for its clinically occult and asymptomatic dissemination. Most ovarian malignancies are diagnosed in the late stages of the disease and the high rate of morbidity is thought to be due, in part, to the highly metastatic nature of ovarian carcinomas. Cancer metastasis relies on the ability of cells to migrate away from primary tumors and invade into target tissues. Though the processes are distinct, cancer cell invasion relies on the underlying migration machinery to invade target tissues.

Cell migration requires the coordinated effort of numerous spatially-regulated signaling …

A Novel Approach For The Identification Of Cytoskeletal And Adhesion A-Kinase Anchoring Proteins, Laura Taylor Director

Graduate College Dissertations and Theses

A-kinase anchoring proteins (AKAPs) are signaling scaffolds which provide spatial and temporal organization of signaling pathways in discrete subcellular compartments. Through tethering the cyclic-AMP dependent protein kinase A (PKA), AKAPs target PKA activity to distinct regions in the cell, bringing PKA in close proximity to its target proteins. This provides a high level of specificity and regulation of PKA and its role in mediating a number of biological processes, one of which is cell migration. Cell migration is a highly dynamic and fundamental process, when misregulated can lead to a number of pathologies. The process of cell migration requires integration …

Direct And Indirect Targets Of Jagged1/Notch1 Signaling In Reactive Astrocytes., Matthew David Lecomte

Graduate College Dissertations and Theses

Stroke or cerebral vascular accident (CVA) is the 4th leading cause of mortality and the principle cause of long-term disability in the United States. Unfortunately, current reperfusion-based treatments (e.g. thrombolysis, tPA) cannot be administered to the majority of patients presenting with ischemic stroke. Accordingly, new treatments for ischemic stroke are desperately needed.

Reactive astrocytes perform key roles in tissue repair and remodeling following stroke such as preservation and repair of the blood-brain barrier, modulation of immune cell invasion, glutamate uptake and neuroprotection, and glial scar formation. The proliferative subpopulation of reactive astrocytes found immediately adjacent to the infarct core after …

Determining The Role Of The Ergic-53 Cargo Receptor Complex In Arenavirus Propagation, Joseph P. Klaus

Graduate College Dissertations and Theses

Arenaviruses and hantaviruses are human pathogens that cause significant morbidity and mortality. The current lack of vaccines and treatment options for these viruses is a global concern. Despite producing only 4 proteins, these viruses are able to maintain a persistent and asymptomatic infection in wild rodents while being continuously shed into the environment. In humans, these viruses cause a spectrum of diseases ranging from aseptic meningitis to severe hemorrhagic fever syndromes. Little is known about how arenavirus and hantavirus proteins engage and interact with the human proteome during the complex process of viral biogenesis, or how the interactions with human …

The Contribution Of Purinergic P2x And P2y Receptors To The Excitability Of Mouse Vomeronasal Sensory Neurons, Jonathan Vick

Graduate College Dissertations and Theses

Olfaction, the sense of smell, allows animals to perceive the multitude of volatile and nonvolatile molecules present in the environment. In many mammals, such as mice and rats, there are four unique chemosensory organs including the (1) main olfactory epithelium (MOE), (2) septal organ, (3) Grüneberg ganglion, and (4) vomeronasal organ (VNO). While the VNO detects some general volatile odorants, it is further specialized for the detection of behaviorally relevant nonvolatile odorants or pheromones. In rodents, the VNO is encased within a bony capsule and located at the base of the nasal cavity. Odorants are detected by vomeronasal sensory neuron …

Mitochondrial Structure And Function As A Therapeutic Target In Malignant Mesothelioma, Brian Cunniff

Graduate College Dissertations and Theses

Malignant mesothelioma (MM) is a rare tumor associated with occupational exposure to asbestos with no effective treatment regime. Evaluation of mitochondrial function in human MM cell lines revealed a common tumor phenotype: in comparison to immortalized or primary human mesothelial cells, MM tumor cells displayed a more oxidized mitochondrial environment, increased expression of mitochondrial antioxidant enzymes, and altered mitochondrial metabolism. Earlier work by our laboratory indicated that increases in mitochondrial reactive oxygen species (mROS) in MM cell lines supports expression of FOXM1, an oncogenic transcription factor that contributes to increased cell proliferation and chemoresistance. These studies sought to investigate targeting …