Neuroscience and Neurobiology Commons^™

Restructuring Of The Axon Initial Segment In Mouse Models Of Neurodevelopmental Disorders, Rachel Ali Rodriguez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Neurodevelopmental disorders (NDDs) affect more than 36% of children in countries with low- and middle- incomes (Boivin, 2015; McCoy, 2016). Interestingly, these heterogeneous disorders share a high incidence of epileptic seizures, suggesting a shared pathology. Seizures result when neuronal firing activity becomes disturbed and neurons fire excessively or in unregulated patterns. A key site in the control of neuronal firing patterns is the axon initial segment (AIS), where the local density of proteins and the morphology of the AIS in part determine the firing of neurons. We hypothesized that a disruption in the morphology and/or composition of the AIS can …

Alzheimer's And Amyloid Beta: Amyloidogenicity And Tauopathy Via Dyshomeostatic Interactions Of Amyloid Beta, Jordan Tillinghast

Senior Honors Theses

This paper reviews functions of Amyloid-β (Aβ) in healthy individuals compared to the consequences of aberrant Aβ in Alzheimer’s disease (AD). As extraneuronal Aβ accumulation and plaque formation are characteristics of AD, it is reasonable to infer a pivotal role for Aβ in AD pathogenesis. Establishing progress of the disease as well as the mechanism of neurodegeneration from AD have proven difficult (Selkoe, 1994). This thesis provides evidence suggesting the pathogenesis of AD is due to dysfunctional neuronal processes involving Aβ’s synaptic malfunction, abnormal interaction with tau, and disruption of neuronal homeostasis. Significant evidence demonstrates that AD symptoms are partially …

Investigating The Effects Of Excitotoxic Stimuli On The Suprachiasmatic Nucleus, Rachel A. Brandes

Chancellor’s Honors Program Projects

No abstract provided.

Characterization Of Sensory And Shelter Enrichment In The Rodent Research Habitat, Amber M. Paul, Yasaman Shirazi-Fard, America Reyes, Moniece Lowe, Margareth Cheng-Campbell, Sungshin Choi, Eduardo Almeida, April Ronca, Ruth K. Globus

Publications

The ISS provides a platform for conducting Rodent Research (RR) in microgravity and 9 missions have been successfully conducted. The results from these experiments have begun to provide new insights into the effects of spaceflight on mammalian physiological systems. After RR-1-4, the Flight IACUC required inclusion of additional cage enrichment into the Rodent Habitats (RH) to “enhance animal well-being by providing animals with sensory and motor stimulation, through structures and resources that facilitate the expression of species typical behaviors”. A Hut, in the form of a rigid, mesh igloo-like shelter was implemented beginning with RR-5. The potential influence of the …

Modeled Microgravity Induces Neutrophil Extracellular Trap (Net)Osis Formation And Reduced Phagocytosis Of Polymorphonuclear Neutrophils, Amber M. Paul

Publications

Spaceflight can dysregulate immunity, by way of increasing granulocytes numbers with impaired function. Polymorphonuclear neutrophils (PMN) are granulocytes that are first responders to infection or injury, and consist of the largest pool of immune cells in humans. PMNs function during innate immunity, through phagocytosis and promotion of inflammation, via the release of reactive oxygen species (ROS) mediators and granule-containing enzymes, such as myeloperoxidase (MPO) and NADPH oxidase-2 (NOX-2). In addition, neutrophil extracellular trap (NET) formation is another mechanism of PMN surveillance that works independently of engulfment phagocytosis, and is a last resort function that can induce NETosis or PMN-specific cell …

Influence Of Social Isolation During Prolonged Simulated Weightlessness By Hindlimb Unloading, Candice G.T. Tahimic, Amber M. Paul, Ann-Sofie Schreurs, Samantha M. Torres, Linda Rubinstein, Sonette Steczina

Publications

The hindlimb unloading (HU) model has been used extensively to simulate the cephalad fluid shift and musculoskeletal disuse observed in spaceflight with its application expanding to study immune, cardiovascular and central nervous system responses, among others. Most HU studies are performed with singly housed animals, although social isolation also can substantially impact behavior and physiology, and therefore may confound HU experimental results. Other HU variants that allow for paired housing have been developed although no systematic assessment has been made to understand the effects of social isolation on HU outcomes. Hence, we aimed to determine the contribution of social isolation …

Meta-Analysis Of Cognitive Performance By Novel Object Recognition After Proton And Heavy Ion Exposures, Eliedonna Cacao, Francis A. Cucinotta

Health Physics & Diagnostic Sciences Faculty Publications

Experimental studies of cognitive detriments in mice and rats after proton and heavy ion exposures have been performed by several laboratories to investigate possible risks to astronauts exposed to cosmic rays in space travel and patients treated for brain cancers with proton and carbon beams in Hadron therapy. However, distinct radiation types and doses, cognitive tests and rodent models have been used by different laboratories, while few studies have considered detailed dose-response characterizations, including estimates of relative biological effectiveness (RBE). Here we report on the first quantitative meta-analysis of the dose response for proton and heavy ion rodent studies of …

Neurodevelopmental Outcomes Of Infantile Hydrocephalus: An Fmri Case Study, Ikhlas Ahmed Hashi

Electronic Thesis and Dissertation Repository

Ventricle dilatation caused by infantile hydrocephalus may result in extensive damage of the posterior cortex (parietal and occipital lobes). We hypothesize that pathological changes in the development of the posterior cortex can be linked to non-verbal learning disabilities in children with previous infantile hydrocephalus. This case study will investigate the neurodevelopmental outcomes of 3 treated hydrocephalus patients, when compared to a group of healthy control children (n = 12). Within the hydrocephalus group, patients displayed differences in non-verbal test performance as well as parietal brain activation during an fMRI number comparison task. We associated these differences with clinical variables such …

Reduced Gabaergic Signaling At The Axon Initial Segment Decreases Vigilance State Transitioning, Austin John Boren

UNLV Theses, Dissertations, Professional Papers, and Capstones

Sleep is a highly regulated homeostatic process that is disrupted in an estimated 50-70 million Americans. Regulation of sleep depends upon coordinated signaling of multiple neurotransmitter systems. In particular, inhibitory gamma-aminobutyric acid (GABA) signaling is required to suppress wake-active brain regions in order to initiate and maintain sleep states. GABA type A receptors (GABAARs) are ionotropic receptors with subunit compositions uniquely enriched on subcellular domains of target cells. α2 subunit-containing GABAARs are the primary target of GABA released onto the axon initial segment (AIS), a site critical for phasing the oscillatory activity of cortical cells. α2-containing GABAARs have previously been …

Development Of Enteric Neurons And Muscularis Macrophages, Marina Avetisyan

Arts & Sciences Electronic Theses and Dissertations

The enteric nervous system (ENS) is a complex interconnected network of neurons and glia in the bowel wall that regulates intestinal motility, blood flow, and epithelial function. The ENS also controls aspects of inflammatory signaling within the bowel. To perform these tasks, there are at least 20 types of enteric neuron and four types of enteric glia. Although much is known about early events in ENS development, signals governing the development of specific neuronal subtypes and communication with neighboring cell types within the bowel remain poorly understood. One fundamental hypothesis is that diverse trophic factors support distinct neuronal populations in …

Deletion Of P38Α Mapk In Microglia Blunts Trauma-Induced Inflammatory Responses In Mice, Josh M. Morganti, Danielle S. Goulding, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

Traumatic brain injury (TBI) is a significant cause of morbidity and mortality in the USA and other developed countries worldwide. Following the initial mechanical insult, the brain’s primary innate immune effector, microglia, initiate inflammatory signaling cascades and pathophysiological responses that can lead to chronic neuroinflammation and neurodegenerative sequelae. The p38α MAPK signaling pathway in microglia is a key contributor to inflammatory responses to diverse disease-relevant stressors and injury conditions. Therefore, we tested here whether microglia p38α contributes to acute and persistent inflammatory responses induced by a focal TBI. We generated conditional cell-specific knockout of p38α in microglia using a CX3CR1 …

Investigating The Role Of Integrin Beta 3 In Dendritic Arborization In The Supragranular Developing Cerebral Cortex, Zachary Logan Holley

Senior Honors Projects, 2010-2019

Integrin subunits have been implicated in axonal and dendritic outgrowth. In particular, a strong positive association has been found between mutations in integrin beta 3 (Itgb3) and autism spectrum disorder, but little is known about neuronal Itgb3 function in vivo. Many forms of autism spectrum disorder are thought to arise from dysfunctional dendritic arborization and synaptic pruning. Global knockout of Itgb3 in mice leads to autistic-like behaviors. Itgb3^-/- mice also have reduced callosal volume, a key neuroanatomical correlate of autism. Here, we test the hypothesis that Itgb3 is required for normal dendritic arborization in layer II/III pyramidal …

Visual And Verbal Serial List Learning In Patients With Statistically-Determined Mild Cognitive Impairment., Victor Wasserman, Sheina Emrani, Emily F Matusz, David Miller, Kelly Davis Garrett, Katherine A Gifford, Timothy J Hohman, Angela L Jefferson, Rhoda Au, Rod Swenson, David J Libon, Consortium For Clinical And Epidemiological Neuropsychological Data Analysis (Cenda).

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Background and Objective: Prior research with patients with mild cognitive impairment (MCI) suggests that visual versus verbal episodic memory test performance may be more sensitive to emergent illness. However, little research has examined visual versus verbal episodic memory performance as related to MCI subtypes.

Research Design and Methods: Patients were diagnosed with non-MCI, amnestic MCI (aMCI), and combined mixed/dysexecutive MCI (mixed/dys MCI). Visual and verbal episodic memory were assessed with the Brief Visuospatial Memory Test-Revised (BVMT-R) and the 12-word Philadelphia (repeatable) Verbal Learning Test (P[r]VLT), respectively.

Results: BVMT-R and P(r)VLT scores yielded similar between-group patterns of performance. Non-MCI patients scored …

Repetitive Mild Traumatic Brain Injury Impairs Performance In A Rodent Assay Of Cognitive Flexibility, Christopher P. Knapp, Doug P. Fox, Ramesh Raghupathi, Laura L. Giacometti, Stan B. Floresco, Barry D. Waterhouse, Rachel L. Navarra

Rowan-Virtua Research Day

Mild traumatic brain injury (mTBI) occurs in almost 80% of the 3 million reported cases of TBI-related emergency department visits each year in the United States. The majority of mTBIs, sometimes classified as concussions, are due to sports-related activities and typically occur repeatedly over the course of an athlete’s career. mTBI symptoms are generally classified as either somatic or neuropsychiatric/cognitive in nature and include impairments in prefrontal cortex mediated functions, including attention, memory, processing speed, reaction times, problem solving, and cognitive flexibility. To date, there remains a major gap in our understanding of the behavioral manifestations, underlying neurobiology, and treatment …

Notch Inhibitors And The Bet Inhibitor Jq-1 Decrease The Growth Of Primary Tumor Cells Derived From A Novel Mouse Model Of C11orf95-Rela Induced Brain Tumor, Ericka Randazzo, Jesse Dunnack, Justin Fang, Joseph Loturco Phd

University Scholar Projects

Brain tumors are the most common childhood solid malignancy, and because of remarkable advances in treating many cancers outside of the brain, they have become the leading cause of cancer mortality in children. Ependymomas are a class of brain tumors which can be further subdivided into three groups based upon their location and genetic features. Of the three classes, supratentorial ependymomas are the only subgroup known to be marked by an oncogenic driver gene, which consists of a fusion mutation between the C11orf95 and RELA genes. C11orf95-RELA positive tumors are the most aggressive and lethal of …

Changes In Hippocampal-Anterior Cingulate Cortex Interactions During Remote Memory Recall, Ryan A. Wirt

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spatial memory is an important cognitive process that relies on extensive neural networks throughout the brain. The hippocampus (HC) is important for the formation of these memories but over time, in a process referred to as consolidation, recall becomes increasingly reliant on other brain areas. The anterior cingulate cortex (ACC), a region within the medial prefrontal cortex, is important for spatial learning, spatial working memory, and remote memory recall, but the mechanisms underlying recall processes are still unknown. To better understand the role of the ACC and HC during memory recall, we introduced rodents into a series of spatially and …

Modeling Changes In Cellular Micro-Environment In Mild To Moderate Head Trauma, Xiangfu Zhang, Subhendra N. Sarkar Phd, Rt

Publications and Research

Our work aims to connect and model multiple small, inter-related tissue injuries as a consequence of mild traumatic brain injuries (mTBI). It has been shown that frontal and temporal lobes are vulnerable regions for brain traumatic injury. A brain injury from a blow or high-speed impact can cause undersurface of the frontal and temporal lobes to deform against the anterior and cranial fossae. This deformation can often trigger damage to the cerebral vasculature, which is ill-understood and can result in chronic damage to larger vessels over time. These physiological injuries can be manifested psychologically; such as patients’ sleep-wake disturbances. The …

Quantifying Expression Of Interneuron Subtype Markers For Dlx-2 Transfected Ng2 Cells, Timothy Nolan

Honors Scholar Theses

Neurons are a post-mitotic cell population, and therefore, they are not able to regenerate in vivo after a traumatic injury. Because inhibitory GABAergic interneurons and oligodendrocyte precursor cells (OPCs) are derived from the same precursor, recent studies have focused on transforming these OPCs into GABAergic neurons. However, there are different types of GABAergic interneurons that have different electrophysiological responses, which can lead to functional differences. The Nishiyama laboratory had already used a key gene in GABAergic interneuron and OPC differentiation, Distal-less homeobox 2 (Dlx-2), to transfect OPCs; early electrophysiology tests showed most of these transfected cells behaved like immature neurons, …

A Hidden Markov Factor Analysis Framework For Seizure Detection In Epilepsy Patients, Mahboubeh Madadi

Graduate Theses and Dissertations

Approximately 1% of the world population suffers from epilepsy. Continuous long-term electroencephalographic (EEG) monitoring is the gold-standard for recording epileptic seizures and assisting in the diagnosis and treatment of patients with epilepsy. Detection of seizure from the recorded EEG is a laborious, time consuming and expensive task. In this study, we propose an automated seizure detection framework to assist electroencephalographers and physicians with identification of seizures in recorded EEG signals. In addition, an automated seizure detection algorithm can be used for treatment through automatic intervention during the seizure activity and on time triggering of the injection of a radiotracer to …

Electroencephalogram As A Diagnostic Tool In Acquired Brain Injury, Michael Zarra

Senior Theses and Projects

The ability of electroencephalogram (EEG) to be used as a diagnostic device for acquired brain injuries (ABI) has been conceptualized previously. Averaged event-related potentials (ERP) derived from an EEG are suitable as markers of dysfunction however, distinctive properties in the frequency domain have not been established previously. In the present study, we examined pre- existing EEG signal data of healthy adults (HA), mild ABI (mABI), and severe ABI (sABI) human groups. Through Fourier analysis performed in MATLAB, we found that individuals in our sample population (n=80) were able to be categorized into their respective group based on common neuronal activity …

Redefining Burnout: Exploring Common Conceptualizations And The Neurophysiology Of Chronic Stress To Establish An Integrated Allostatic Model, Danny A. Guzzi

Dissertations

Burnout is a widely researched stress-related phenomenon associated with numerous adverse outcomes for employees and organizations. Unfortunately, burnout is not well understood and research to this point has been flawed due to a lack of consensus on the definition, dimensionality, and context of the construct. Prevalent conceptualizations of burnout have been criticized for being arbitrarily developed without solid theoretical foundation and for failing to clearly distinguish burnout from depression or other work-related conditions such as compassion fatigue, secondary traumatization, and vicarious traumatization. The current project first examines relevant literature to identify commonalities among prevalent burnout conceptualizations. Then relevant stress research …

Effects Of Altered Gravity On The Central Nervous System Of Drosophila Melanogaster, Amber M. Paul, Siddhita Mhatre, Janani Iyer, Jhony A. Zavaleta, Ravikumar Hosamani

Publications

A comprehensive understanding of the effects of spaceflight and altered gravity on human physiology is necessary for continued human space exploration and long-term space habitation. Spaceflight includes multiple factors such as microgravity, hyper gravity, ionizing radiation, physiological stress, and disrupted circadian rhythms and these have been shown to contribute to pathophysiological responses that target immunity, bone and muscle integrity, cardiovascular and nervous systems. In terrestrial conditions, some of these factors can lead to cancer and neuroimmunological disorders. In this study, we used a well-established spaceflight model organism, Drosophila melanogaster, to assess spaceflight-associated changes in the nervous system. We hypothesize that …

Absence Of Endothelial Α5Β1 Integrin Triggers Early Onset Of Experimental Autoimmune Encephalomyelitis Due To Reduced Vascular Remodeling And Compromised Vascular Integrity, Ravi Kant, Sebok K. Halder, Gregory J. Bix, Richard Milner

Sanders-Brown Center on Aging Faculty Publications

Early in the development of multiple sclerosis (MS) and its mouse model experimental autoimmune encephalomyelitis (EAE), vascular integrity is compromised. This is accompanied by a marked vascular remodeling response, though it is currently unclear whether this is an adaptive vascular repair mechanism or is part of the pathogenic process. In light of the well-described angiogenic role for the α5β1 integrin, the goal of this study was to evaluate how genetic deletion of endothelial α5 integrin (α5-EC-KO mice) impacts vascular remodeling and repair following vascular disruption during EAE pathogenesis, and how this subsequently influences clinical progression and inflammatory demyelination. Immunofluorescence staining …

White Matter Hyperintensities In Vascular Contributions To Cognitive Impairment And Dementia (Vcid): Knowledge Gaps And Opportunities, Jessica Alber, Suvarna Alladi, Hee-Joon Bae, David A. Barton, Laurel A. Beckett, Joanne M. Bell, Sara E. Berman, Geert Jan Biessels, Sandra E. Black, Isabelle Bos, Gene L. Bowman, Emanuele Brai, Adam M. Brickman, Brandy L. Callahan, Roderick A. Corriveau, Silvia Fossati, Rebecca F. Gottesman, Deborah R. Gustafson, Vladimir Hachinski, Kathleen M. Hayden, Alex M. Helman, Timothy M. Hughes, Jeremy D. Isaacs, Angela L. Jefferson, Sterling C. Johnson, Alifiya Kapasi, Silke Kern, Jay C. Kwon, Juraj Kukolja, Athene Lee, Brittani R. Price, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

White matter hyperintensities (WMHs) are frequently seen on brain magnetic resonance imaging scans of older people. Usually interpreted clinically as a surrogate for cerebral small vessel disease, WMHs are associated with increased likelihood of cognitive impairment and dementia (including Alzheimer's disease [AD]). WMHs are also seen in cognitively healthy people. In this collaboration of academic, clinical, and pharmaceutical industry perspectives, we identify outstanding questions about WMHs and their relation to cognition, dementia, and AD. What molecular and cellular changes underlie WMHs? What are the neuropathological correlates of WMHs? To what extent are demyelination and inflammation present? Is it helpful to …

Using Fundamental Properties Of Light To Investigate Photonic Effects In Condensed Matter And Biological Tissues, Laura A. Sordillo

Dissertations and Theses

Light possesses characteristics such as polarization, wavelength and coherence. The interaction of light and matter, whether in a semiconductor or in a biological sample, can reveal important information about the internal properties of a system. My thesis focuses on two areas: photocarriers in gallium arsenide and biomedical optics. Varying the excitation wavelength can be used to study both biological tissue and condensed matter. I altered the excitation wavelengths to be in the longer near-infrared (NIR) optical windows, in the shortwave infrared (SWIR) range, a wavelength region previously thought to be unusable for medical imaging. With this method, I acquired high …

Targeting Maladaptive Plasticity After Spinal Cord Injury To Prevent The Development Of Autonomic Dysreflexia, Khalid C. Eldahan

Theses and Dissertations--Physiology

Vital autonomic and cardiovascular functions are susceptible to dysfunction after spinal cord injury (SCI), with cardiovascular dysregulation contributing to morbidity and mortality in the SCI population. Autonomic dysreflexia (AD) is a condition that develops after injury to the sixth thoracic spinal segment or higher and is characterized by potentially dangerous and volatile surges in arterial pressure often accompanied with irregular heart rate, headache, sweating, flushing of the skin, and nasal congestion. These symptoms occur in response to abnormal outflow of sympathetic activity from the decentralized spinal cord typically triggered by noxious, yet unperceived nociceptive stimulation beneath the level of lesion. …

Agent Based Model Of Cavitation In Spinal Cord Injury, Rahma Ahmed

Senior Projects Spring 2019

Annually, approximately 375,000 people suffer from spinal cord injury (SCI) worldwide and many SCI patients develop secondary health conditions such as respiratory, cardiovascular, and urinary/bowel complications which negatively impact their daily lives. SCI occurs when there is damage to the spinal cord resulting in decreased motor functions, decreased sensory functions, or paralysis. Days to weeks after initial impact, the lesion (area of injury) continues to increase in size in a process called progressive cavitation which demyelinates axons and inhibits effective axonal regeneration. In an in vitro model of progressive cavitation, Fitch et al. showed that activated macrophages cause cavities to …

Autologous Peripheral Nerve Grafts To The Brain For The Treatment Of Parkinson's Disease, Andrew Welleford

Theses and Dissertations--Neuroscience

Parkinson’s disease (PD) is a disorder of the nervous system that causes problems with movement (motor symptoms) as well as other problems such as mood disorders, cognitive changes, sleep disorders, constipation, pain, and other non-motor symptoms. The severity of PD symptoms worsens over time as the disease progresses, and while there are treatments for the motor and some non-motor symptoms there is no known cure for PD. Thus there is a high demand for therapies to slow the progressive neurodegeneration observed in PD. Two clinical trials at the University of Kentucky College of Medicine (NCT02369003, NCT01833364) are currently underway that …

Neuroprotective Strategies Following Experimental Traumatic Brain Injury: Lipid Peroxidation-Derived Aldehyde Scavenging And Inhibition Of Mitochondrial Permeability Transition, Jacqueline Renee Kulbe

Theses and Dissertations--Neuroscience

Traumatic brain injury (TBI) represents a significant health crisis. To date there are no FDA-approved pharmacotherapies available to prevent the neurologic deficits caused by TBI. Following TBI, dysfunctional mitochondria generate reactive oxygen and nitrogen species, initiating lipid peroxidation (LP) and the formation of LP-derived neurotoxic aldehydes, which bind mitochondrial proteins, exacerbating dysfunction and opening of the mitochondrial permeability pore (mPTP), resulting in extrusion of mitochondrial sequestered calcium into the cytosol, and initiating a downstream cascade of calpain activation, spectrin degradation, neurodegeneration and neurologic impairment.

As central mediators of the TBI secondary injury cascade, mitochondria and LP-derived neurotoxic aldehydes make promising …

Antibodies In The Diagnosis, Prognosis, And Prediction Of Psychotic Disorders., Thomas A Pollak, Jonathan P Rogers, Robert G Nagele, Mark Peakman, James M Stone, Anthony S David, Philip Mcguire

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Blood-based biomarker discovery for psychotic disorders has yet to impact upon routine clinical practice. In physical disorders antibodies have established roles as diagnostic, prognostic and predictive (theranostic) biomarkers, particularly in disorders thought to have a substantial autoimmune or infective aetiology. Two approaches to antibody biomarker identification are distinguished: a "top-down" approach, in which antibodies to specific antigens are sought based on the known function of the antigen and its putative role in the disorder, and emerging "bottom-up" or "omics" approaches that are agnostic as to the significance of any one antigen, using high-throughput arrays to identify distinctive components of the …