Medicine and Health Sciences Commons^™

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 …

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 …

Drug-Induced Autoimmune Hepatitis From Hydralazine Leading To Acute Liver Failure And Liver Transplantation, Jasleen Grewal, Angela Doan, Annie S. Hong, Arpit Amin, Jason V. Scapa, Ramy Hanna, Francisco Durazo, Beshoy Yanny

School of Medicine Faculty Publications

We describe a woman with no previous liver disease who developed drug-induced autoimmune hepatitis from hydralazine prescribed to her for hypertension. Despite the discontinuation of the medication, she developed acute liver failure and subsequently underwent successful liver transplantation. She survived and had a good clinical outcome.

Response Of Human Small Intestinal Epithelium To Fractionated Irradiation: Dynamical Modeling Approach, Francis A. Cucinotta, Olga A. Smirnova

Health Physics & Diagnostic Sciences Faculty Publications

A biologically motivated mathematical model of the dynamics of the small intestinal epithelium in humans treated with fractionated radiotherapy has been developed and is further investigated here. This model, originating from our previous work, is implemented as a system of nonlinear ordinary differential equations, in which the variables and parameters have a clear biological meaning. The model also includes, as input, the key parameters of fractionated irradiation. The modeling results on the dynamical response of the human normal small intestinal epithelium to fractionated radiation therapy regimens were in agreement with the corresponding empirical data, which, in turn, demonstrates the capability …

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 …

Further Analyses Of The Safety Of Verubecestat In The Phase 3 Epoch Trial Of Mild-To-Moderate Alzheimer’S Disease, Michael F. Egan, Yuki Mukai, Tiffini Voss, James Kost, Julie Stone, Christine Furtek, Erin Mahoney, Jeffrey L. Cummings, Pierre N. Tariot, Paul S. Aisen, Bruno Vellas, Christopher Lines, David Michaelson

Integrated Health Sciences Faculty Publications

Background: Verubecestat, a BACE1 inhibitor that reduces Aβ levels in the cerebrospinal fluid of humans, was not effective in a phase 3 trial (EPOCH) of mild-to-moderate AD and was associated with adverse events. To assist in the development of BACE1 inhibitors, we report detailed safety findings from EPOCH. Methods: EPOCH was a randomized, double-blind, placebo-controlled 78-week trial evaluating verubecestat 12 mg and 40 mg in participants with mild-to-moderate AD diagnosed clinically. The trial was terminated due to futility close to its scheduled completion. Of 1957 participants who were randomized and took treatment, 652 were assigned to verubecestat 12 mg, 652 …

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 …

Sub-Region Based Radiomics Analysis For Survival Prediction In Oesophageal Tumours Treated By Definitive Concurrent Chemoradiotherapy, Congying Xie, Pengfei Yang, Xuebang Zhang, Lei Xu, Xiaoju Wang, Xiadong Li, Luhan Zhang, Ruifei Xie, Ling Yang, Zhao Jing, Hongfang Zhang, Lingyu Ding, Yu Kuang, Tianye Niu, Shixiu Wu

Health Physics & Diagnostic Sciences Faculty Publications

Background: Evaluating clinical outcome prior to concurrent chemoradiotherapy remains challenging for oesophageal squamous cell carcinoma (OSCC) as traditional prognostic markers are assessed at the completion of treatment. Herein, we investigated the potential of using sub-region radiomics as a novel tumour biomarker in predicting overall survival of OSCC patients treated by concurrent chemoradiotherapy. Methods: Independent patient cohorts from two hospitals were included for training (n = 87) and validation (n = 46). Radiomics features were extracted from sub-regions clustered from patients' tumour regions using K-means method. The LASSO regression for ‘Cox’ method was used for feature selection. The survival prediction model …

Health Care-Associated Infection Prevention Outcomes: Evaluating The Link Between Infection Prevention Practices In Healthcare Facilities And Their Health Care-Associated Infection Rates, Chidinma Veronica Njoku

UNLV Theses, Dissertations, Professional Papers, and Capstones

Healthcare-associated infections (HAI) are a pressing problem affecting vulnerable individuals who come to the hospital to receive care for one condition only to find that they have contracted another during their stay. Studies point to the importance of training and educating staff in order to implement and comply with recommended infection control and prevention control and prevention practices as lack of training and knowledge about infection control and prevention has been perceived to bring about a limited ability for direct care staff to adhere to recommended processes and activities. Although there are prior studies on the effects of assessments, infection …

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 …

Implementation Of An Asthma Action Plan In A Pediatric Outpatient Clinic, Noelle Cerdan

UNLV Theses, Dissertations, Professional Papers, and Capstones

A combination of asthma evidence-based education by nurse practitioners and other healthcare providers as well as self-management by patients with asthma and their caregivers are necessary to provide effective asthma care. According to the National Asthma Education and Prevention Program (NAEPP) guidelines from the National Institute of Health (NIH), effective asthma care includes a detailed Asthma Action Plan (AAP). However, despite this evidence-based recommendation for all patients with asthma, studies suggest many healthcare providers do not routinely utilize an AAP.

The purpose of this Doctor of Nursing Practice (DNP) project was to develop and evaluate a process for the integration …

Uptake And Persistence Of Bacterial Magnetite Magnetosomes In A Mammalian Cell Line: Implications For Medical And Biotechnological Applications., Jefferson Cypriano, Jacques Werckmann, Gabriele Vargas, Adrana Lopes Dos Santos, Karen T. Silva, Pedro Leao, Fernando P. Almeida, Dennis A. Bazylinski, Marcos Farina, Ulysses Lins, Fernanda Abreu

Life Sciences Faculty Research

Magnetotactic bacteria biomineralize intracellular magnetic nanocrystals surrounded by a lipid bilayer called magnetosomes. Due to their unique characteristics, magnetite magnetosomes are promising tools in Biomedicine. However, the uptake, persistence, and accumulation of magnetosomes within mammalian cells have not been well studied. Here, the endocytic pathway of magnetite magnetosomes and their effects on human cervix epithelial (HeLa) cells were studied by electron microscopy and high spatial resolution nano-analysis techniques. Transmission electron microscopy of HeLa cells after incubation with purified magnetosomes showed the presence of magnetic nanoparticles inside or outside endosomes within the cell, which suggests different modes of internalization, and that …