Neurosciences Commons^™

The Effects Of Chronic Calcium Dysregulation On Behavioral And Pathological Features Of Alzheimer's Disease, Jonathan Sabbagh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer's disease (AD) is a progressive neurodegenerative disorder whose etiology is unknown. Recent studies have implicated alterations in calcium homeostasis as a pathogenic contributor to AD. Calcium dysregulation has been observed in aged and AD brains, an event which could potentially facilitate the development of multiple pathologies observed in AD. Specifically, disrupting intracellular calcium levels in vitro has been demonstrated to increase amyloid-beta (Aβ) production, tau phosphorylation, and neuronal loss. However, there is a paucity of data on the behavioral and biochemical consequences of chronic in vivo perturbation of calcium homeostasis. In a series of experiments designed to evaluate the …

Using Over-The-Counter Ear Filters As A Treatment To Improve Dizziness And Balance In Patients Diagnosed With A Traumatic Brain, Brandy Sue Whitney

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background and purpose: People diagnosed with a Traumatic Brain Injury (TBI) usually have physical, cognitive, emotional, and sleep deficits. Sensory overload is a common symptom of TBI. One treatment prescribed for sensory overload is over the counter ear filters. Ear filters have shown to decrease sensory input. Could the ear filters have an effect on balance and dizziness without much cost to the patient or the clinic?

Subjects: Patients diagnosed with a mild or moderate brain injury, ages of 18-65 years old. They needed to be medically stable, potential to walk, and have complaints of dizziness and/or balance problems.

Methods: …

Frequency-Specificity And Pattern-Specificity Of The Buildup Of Auditory Stream Segregation, David Michael Weintraub

UNLV Theses, Dissertations, Professional Papers, and Capstones

During repeating sequences of low (A) and high (B) tones in an "...ABAB..." pattern, the likelihood of hearing two separate streams ("streaming") increases with more repetitions of the patterns, a phenomenon referred to as "buildup". Previous studies have shown that buildup is frequency specific (Anstis & Saida, 1985) and that its biasing effects decays over several seconds (Beauvois & Meddis, 1997). No study has examined whether the frequency specificity of buildup persists for such a long duration. To address these issues, Experiment 1 tested the decay of frequency-specific and non-frequency specific buildup. The results revealed that (1) frequency-specific buildup effects …

Exercise-Induced Neuroprotection In A Hemiparkinsonian 6-Hydroxydopamine Rat Model, Merrill Russen Landers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Outside of finding a cure, one of the preeminent goals of research in Parkinson's disease (PD) is finding a neuroprotective treatment that when applied prior to the onset of the disease will decrease the risk and severity of the subsequent disease. One such treatment that has potential as a neuroprotective agent in PD is exercise. Several studies have found forced exercise to be protective of Parkinson's disease in adult rodent models; however, few of these studies have used a design wherein voluntary exercise was evaluated. Moreover, no study has used a true neuroprotective design in which exercise was applied prior …

Effects Of Hyperthermia On Photochemical Internalization-Mediated Delivery Of Bleomycin, Christina Schlazer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Standard treatment protocols for high-grade gliomas, such as glioblastoma multiforme (GBM), are highly ineffective due to their inability to eradicate infiltrating tumor cells. Improvements in overall survival are likely to be realized only with the development of more effective localized therapies capable of eradicating tumor cells in the surgical resection margin and beyond. Photochemical internalization (PCI) is a localized light-based therapeutic modality that enhances the efficacy of therapeutic macromolecules including chemotherapeutic agents such as bleomycin. A number of studies have shown that this photodynamic therapy (PDT) - based modality may prove effective in the treatment of high-grade gliomas.

Three-dimensional multicell …

An Investigation Of The Role Of Gabab Ligands On Cued And Contextual Fear Conditioning, Chelcie F. Heaney

UNLV Theses, Dissertations, Professional Papers, and Capstones

GABA is the primary inhibitory neurotransmitter in the brain and mediates several processes, including learning and memory. Activating or inhibiting GABA receptors allows for the examination of the effects of altered GABAergic signaling on these processes. The two main receptors, GABAA and GABAB, each have a different mechanism of action when activated, thus they may contribute differentially to learning and memory. The metabotropic GABAB receptor responds with the activation of several intracellular signaling cascades, which provide long-lasting inhibitory effects that primarily mediate network function. Conversely, the GABAA receptor is an ion channel that contributes more immediate inhibitory effects through the …

A Diffusion Tensor Imaging Software Comparison And Between Control Subjects And Subjects With Known Anatomical Diagnosis, Michael C. Moore

UNLV Theses, Dissertations, Professional Papers, and Capstones

Diffusion weighted imaging (DWI) is a magnetic resonance imaging (MRI) method that produces in vivo images of biological tissues weighted with the local micro-structural characteristics of water diffusion. Diffusion tensor imaging (DTI), a form of DWI, is useful when a tissue, such as the neural axons of white matter in the brain, has an internal fibrous structure that allows water to diffuse more rapidly in alignment with the fibers. Changes in the water diffusion pattern indicate changes in the fiber structure which can result from damage to the fibers. Measurements of the water diffusion patterns include overall diffusivity, Apparent Diffusion …

Executive Function Profiles In Pediatric Traumatic Brain Injury, Erik Nelson Ringdahl

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traumatic brain injury is a common cause of disability and death among children in the United States. Insult to the frontal and temporal lobes are frequent in closed head brain injury. Cognitive deficits in a variety of domains are common sequelae of brain trauma. In many cases, trauma to the frontal and temporal lobe regions engender prominent deficits in higher-order cognitive processing, memory, and attention.

Higher-order cognitive processing, or Executive Functions are the grouping of cognitive processes necessary for organization of thoughts and activities, attending to the activities, prioritizing tasks, managing time efficiently, and making decisions (Alvarez & Emory, 2006; …

The Effect Of Spiritualism On The Neuropsychological Function Of Memory, Carla Farcello

McNair Poster Presentations

The amount of physiological-neurological research performed over the past few years has dramatically increased due to our ability to view the structure and function of the brain in living human beings. The use of imaging tools has resulted in huge strides forward in unlocking some of the mysteries of the 3 pound universe-the human brain. One of the more unique neural processes being recently addressed is the affect of belief and spiritualism-the sense of being connected to something larger than oneself-on the human brain. This study hypothesized that better memory will be documented among the experimental group who report being …

Protocol Variation Analysis Of Whole Brain Ct Perfusion In Acute Ischemic Stroke, Peter T. Heiberger

UNLV Theses, Dissertations, Professional Papers, and Capstones

Computed tomography perfusion (CTP) analysis is a rapidly advancing imaging modality that is improving diagnosis of brain abnormalities in patients suffering from hemorrhagic or ischemic stroke, traumatic brain injury, vascular occlusion and numerous other conditions. Through the advancements of computed tomography (CT) imaging, including the introduction of the 320-detector row CT with a 16 centimeter range in the z-axis enabling whole brain CTP, perfusion analysis now has a significantly increased clinical utility that is useful for both diagnosis and treatment of central nervous system (CNS) conditions. This study focuses on the procedural and analytical approach to the diagnostic evaluation of …

Donepezil And Galanin Interactions In An Animal Model Of Alzheimer’S Disease, Jonathan J. Sabbagh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer's disease (AD) is a neurodegenerative disorder marked by a progressive loss of cognitive function. One of the neurobiological hallmarks of AD is a progressive loss of cholinergic neurons and a decrease in the amount of acetylcholine in the brain. Pharmacological therapies have targeted the cholinergic system, specifically first-line, palliative treatment using acetylcholinesterase (AChE) inhibitors, such as donepezil. Donepezil has been shown to increase cholinergic tone and ameliorate some of the cognitive deficits in AD patients. Galanin, a neuropeptide that inhibits the evoked release of several neurotransmitters including acetylcholine as well as modulates seveal intracellular cascades, is overexpressed in AD …

Development Of A Functional Mri Olfactory Protocol, Jeremy Mangum

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many people can spend a few days with an acute form of sinusitis, a stuffy nose, or sinus congestion that inhibits their ability to smell, but there are fourteen million Americans over the age of fifty that suffer from some form of chronic olfactory dysfunction. Some neurological disorders such as Parkinson's disease and Alzheimer's disease have demonstrated that olfactory dysfunction is a frequent and early sign. While these diseases have no known cure, there are medicines that exist to slow the progression of such debilitating illnesses. By identifying such diseases in their early stages, we can improve the quality of …

Unlv Magazine, Cate Weeks, Shane Bevell, Erin O'Donnell, Eric Leake, Lori Bachand, David G. Schwartz, David Ashley

UNLV Magazine

No abstract provided.

A Critical Role For Kalirin In Ngf Signaling Through Trka, Kausik Chakrabarti, Rong Lin, Noraisha I. Schiller, Yanping Wang, David Koubi, Ying-Xin Fan, Brian B. Rudkin, Gibbes R. Johnson, Martin R. Schiller

Life Sciences Faculty Research

Kalirin is a multidomain guanine nucleotide exchange factor (GEF) that activates Rho proteins, inducing cytoskeletal rearrangement in neurons. Although much is known about the effects of Kalirin on Rho GTPases and neuronal morphology, little is known about the association of Kalirin with the receptor/signaling systems that affect neuronal morphology. Our experiments demonstrate that Kalirin binds to and colocalizes with the TrkA neurotrophin receptor in neurons. In PC12 cells, inhibition of Kalirin expression using antisense RNA decreased nerve growth factor (NGF)-induced TrkA autophosphorylation and process extension. Kalirin overexpression potentiated neurotrophin-stimulated TrkA autophosphorylation and neurite outgrowth in PC12 cells at a low …

Kalirin Dbl-Homology Guanine Nucleotide Exchange Factor 1 Domain Initiates New Axon Outgrowths Via Rhog-Mediated Mechanisms, Victor May, Martin R. Schiller, Betty A. Eipper, Richard E. Mains

Life Sciences Faculty Research

The large multidomain Kalirin and Trio proteins containing dual Rho GTPase guanine nucleotide exchange factor (GEF) domains have been implicated in the regulation of neuronal fiber extension and pathfinding during evelopment. In mammals, Kalirin is expressed predominantly in the nervous system, whereas Trio, broadly expressed throughout the body, is expressed at a lower level in the nervous system. To evaluate the role of Kalirin in fiber initiation and outgrowth, we microinjected cultured sympathetic neurons with vectors encoding Kalirin or with Kalirin antisense oligonucleotides, and we assessed neuronal fiber growth in a serum-free, satellite cell-free environment. Kalirin antisense oligonucleotides blocked the …