Medicine and Health Sciences 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 …

Trade-Offs Between Survival And Reproduction In Starvation-Selected Drosophila Melanogaster, Tammara Beeghly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evolutionary outcomes are demonstrated by traits that affect an organism’s schedule of reproduction and survival. These life history traits are reflected in an organism’s physiology, development and behavior. Environmental changes, such as availability of nutritional resources, can profoundly affect evolutionary outcomes of individuals and populations. When shortages arise, there will be trade-offs in the allocation of resources, where one trait prevails at the expense of another.

In the laboratory, we can mimic conditions in nature and study the specific effects of the conditions that we re-create. In our case, over 100 generations of Drosophila melanogaster have been selected for starvation …

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 …

Optimization Of Motor Performance, Lee-Kuen Chua

UNLV Theses, Dissertations, Professional Papers, and Capstones

According to the OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention of Learning) theory of motor learning, enhanced expectancies (EE), autonomy support (AS), and external focus (EF) augment the coupling of a person’s actions to intended movement goals. This goal-action coupling is postulated to boost a person’s focus on goal-related aspects of the motor task while reducing the person’s self-related thoughts, resulting in enhanced performance of skilled movements as well as in improving the acquisition outcomes for the learning of motor skills. The three studies in this compilation report were aimed at providing empirical evidence for the motor performance benefits …

Prevalence Of Aggregatibacter Actinomycetemcomitans And Fusobacterium Nucleatum Among Clinical Orthodontic Saliva Samples, Jason Robert Klingler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Changes to the oral microflora occur when there are shifts in the levels of the numerous bacterial species. Changes in bacterial load occur in health, disease, and dental treatments such as orthodontics and can be detected through saliva. Many studies dealing with saliva have centered around detecting bacteria known for correlation with chronic periodontitis and caries. Fewer have focused on bacterial species that contribute to microbial shifts not strictly correlated with disease. Measuring the degree of disease progression or future susceptibility is not always possible with traditional clinical parameters alone.

Aggregatibacter actinomycetemcomitans (AA) is a bacterial strain that serves as …

Wearable Technology Devices: Heart Rate And Step Count Analysis, Jeffrey Montes

UNLV Theses, Dissertations, Professional Papers, and Capstones

The overarching purpose of this dissertation was to evaluate and analyze heart rate and/or step count measurements for six popular wearable technology devices: the Samsung Gear 2, FitBit Surge, Polar A360, Garmin Vivosmart HR+, Leaf Health Tracker, and the Scosche Rhythm+ in four separate conditions: free motion walking, free motion jogging, treadmill walking, and treadmill jogging. The four studies presented here utilized one test design and data collection protocol in which many measurements could be addressed simultaneously. Currently, there is no accepted standardized protocol to evaluate wearable technology devices. The test design utilized for this research series was introduced as …

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 …