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Impact Of Gas Supersaturation On The Development Of Gas Bubble Trauma In Paedomorphic Eurycea Salamanders, Trent Furr

Biology Theses

There are eleven species of paedomorphic lungless salamanders endemic to Texas. Of these, eight are considered threatened by the International Union for Conservation of Nature (IUCN). One of these, the Barton Springs Salamander (Eurycea sosorum), is found only in springs and aquifers in and around Austin, Texas. A large population of this species is found in Barton Springs, located in Austin, TX–where dissolved gas saturation has been measured as high as 134%. Morbidity and mortality events in Barton Springs Salamanders have been documented coinciding with periods of dissolved gas supersaturation. This study seeks to understand what environmental conditions lead to …

Understanding Pancreatic Islet Stress Responses And Developing Strategies To Improve Transplantation Grafts, Marlie Maria Maestas

Arts & Sciences Graduate Student Theses and Dissertations

Diabetes mellitus is a chronic metabolic disorder affecting millions worldwide, characterized by hyperglycemia resulting from defects in insulin secretion or action. While current treatments range from pharmacotherapy to experimental cell-based therapies, progress remains hampered by donor scarcity and an incomplete understanding of islet stress responses. This dissertation investigates cellular stress responses in pancreatic islets and strategies to improve stem cell-derived islet (SC-islet) transplantation. The first chapter provides an overview of diabetes pathophysiology, modeling approaches, and treatment options. In the second chapter, we use single-cell RNA sequencing to investigate cell-type-specific responses to diabetes-associated stress in primary human islets exposed to endoplasmic …

Understanding The Role Of Hd5 In Colonic Epithelial Cell Death, Maryam M. Gerges, Amanda D. Williams

Student Scholar Symposium

Inflammatory bowel disease (IBD) is an autoimmune disorder where the immune system attacks healthy tissue. IBD can occur in both adults and children, describing Ulcerative Colitis (UC) and Crohn’s Colitis (CC). Our lab studies human alpha defensin 5 (HD5), an antimicrobial peptide that normally maintains small intestinal sterility. However, in CC patients, HD5 is overexpressed in the colon. Preliminary data suggests that HD5 increases colonic cell death. This project aims to determine if HD5 induces apoptosis and its mechanisms. To this end, we will test if the suppression of caspase enzymes with a pan-caspase inhibitor reduces cell death triggered by …

Impact Of Zar1l Expression On Drug Response In Breast Cancer Cells, Maryam M. Gerges, Smita Misra

Student Scholar Symposium

Breast cancer (BC) is the most common cancer in women worldwide and the second leading cause of cancer-related deaths among females. BC arises from the uncontrolled proliferation of breast epithelial cells. A crucial gene associated with BC is the Breast Cancer Susceptibility Gene 2 (BRCA2), a tumor suppressor that aids in DNA repair. Proper BRCA2 function helps prevent BC. Our lab studied the cell cycle-dependent expression of BRCA2 revealing that its promoter exhibits bi-directional activity. During cell division, forward activity transcribes BRCA2, while in the resting phase, reverse activity transcribes ZAR2 (Zygote Arrest 1 Like). ZAR2, an RNA-binding protein with …

The Role Of Human Alpha Defensin 5 (Hd5) In Disrupted Wound Healing Processes In Crohn’S Colitis, Jafer Aljorani, Amanda Williams

Student Scholar Symposium

Wound healing is a complex biological process requiring the coordinated function of multiple proteins. In chronic inflammatory bowel disease (IBD), particularly Crohn’s Colitis (CC), this process is dysregulated, leading to delayed tissue repair and increased disease burden. Prior studies indicate that Human Alpha Defensin 5 (HD5) is over-expressed in the colonic epithelium of CC patients, yet its impact on wound healing remains poorly understood. Our laboratory has identified that HD5 may impair wound healing by modulating key structural and regulatory proteins. Preliminary findings suggest that HD5 reduces the expression and function of desmoplakin, a critical desmosomal protein essential for maintaining …

Functionality Of The Ryanodine Receptor Type 1 (Ryr1) In The Development Of Malignant Hyperthermia (Mh), Cesar Medina, Joshua Owens

Student Scholar Symposium

Malignant Hyperthermia (MH) is a rare but potentially lethal pharmacogenetic disorder, affecting roughly 1 in 30,000 children and 1 in 100,000 adults undergoing surgery. MH can be triggered by agents used for general anesthesia. These may include volatile anesthetics such as sevoflurane, isoflurane, desflurane, halothane or depolarizing neuromuscular blockers such as succinylcholine. Upon administration of a trigger, an MH susceptible (MHS) patient can develop a hypermetabolic state during the intraoperative or postoperative periods. If not treated quickly, an MH episode could result in organ dysfunction or death. The primary mechanisms involved in the development of an MH crisis include the …

Her2 Amplification In Breast Cancer And Its Treatment Options, Emerald Cole, Zoe Grace Brigance

Student Scholar Symposium

Breast cancer affects approximately 2.3 million women worldwide, causing an estimated 670,000 deaths in 2022. Among its subtypes, 15-20% exhibit overexpression of Human Epidermal Growth Factor Receptor 2 (HER2), a tyrosine kinase receptor that drives tumor aggressiveness. HER2 activates the PI3K and RAS/RAF/MAPK pathways, promoting uncontrolled cell growth, proliferation, and survival. In HER2+ breast cancer, gene amplification leads to excess HER2 protein production, resulting in persistent signaling and unchecked tumor progression. However, this dependency on HER2 presents a key therapeutic opportunity. Trastuzumab, an anti-HER2 monoclonal antibody, inhibits HER2 signaling and enhances immune-mediated cancer cell destruction. When combined with Lapatinib, chemotherapy, …

The Effect Of Diet On Hydrogen Sulfide Tolerance Of Extremophile Fishes, Kyliyah Walker, Michael Tobler, Bethany Williams

Undergraduate Research Symposium

Poecilia mexicana are a species of live-bearing fish that have adapted to surviving in hydrogen sulfide (H₂S) abundant waters. Sites that are high in toxic H₂S are also characterized by low levels of oxygen, making any organism that inhabits these tough conditions to be deemed extremophiles. Tolerance of these multiple stressors is impacted by numerous external environmental factors. The question being addressed in this study is if diet affects how well these fish tolerate H₂S. I used 80 laboratory-bred female P. mexicana originating from two sulfidic and non-sulfidic population. Half of the fish from …

Measuring Welfare Of Wild Tarantulas During Field Surveys Using Heart Rate, Tim Angelo Artiaga Lopez, Becky Hansis-O'Neill, Aimee Dunlap Phd

Undergraduate Research Symposium

Tarantulas (Theraposidae) are predatory arachnids that can help control populations of herbivorous arthropods. We have been monitoring populations of the Missouri brown tarantula (Aphonopelma hentzi) in Missouri glades for three seasons and have questions about their welfare during these surveys. Unlike mammals, arthropods are not extensively researched and there are only a few known facts about measuring their welfare. Managing stress for wild animals during field surveys is important for reducing the potential negative impacts of research. In mammals, increased heart rate is positively correlated with negative stress and eustress. Using the same logic, we hypothesized that heart rate could …

Phenotypic Variations Between The European Paper Wasps, Senna V. Horak, Thomas Hagan, Sara Miller

Undergraduate Research Symposium

The European paper wasp (Polistes Dominula) is a widespread invasive Hymenoptera species in the US, commonly known for their black and yellow markings. Phenotypic variations, primarily in color patterns and size, play a significant role in understanding their interactions among other wasps and effects of environmental factors on the species. In this study, we examined phenotypic variation within and between populations by measuring head width, intertegular distance, and femur and tibia length.

Habitat Disturbance And Biodiversity In Glade Habitats, Maddie Smith, Becky Hansis-O'Neill, Aimee Dunlap Phd

Undergraduate Research Symposium

The Ozark glades are home to a variety of reptiles, amphibians, rodents, and invertebrates such as tarantulas and scorpions. Glade inhabitants face challenges like habitat fragmentation and degradation, but they could be facing even bigger challenges as outdoor recreation becomes more popular. People looking for wildlife to photograph or collect often look under rocks without leaving them how they were found. This study focused on monitoring rock disturbance at two protected glades- Shaw Nature Preserve and a more accessible undisclosed glade in Jefferson County. Disturbing the glade habitat to look for wildlife is prohibited at both sites. Twenty rocks at …

Targeting Pancreatic Cancer With Rapamycin-Loaded Gold Nanoparticles Conjugated To Egf Peptide: Studies On Cytotoxicity And Uptake Mechanisms Aided By Proteomic Analysis, Adeolu Oluremi

Theses and Dissertations

Pancreatic cancer remains one of the most lethal malignancies, with a five-year survival rate below 5%. While rapamycin (Rap) has demonstrated therapeutic potential, its clinical utility is hampered by systemic toxicity. To address this limitation, this study developed a targeted nanocarrier system using gold nanospheres (AuNPs) functionalized with the Epidermal Growth Factor Receptor (EGFR) peptide GE11 for the specific delivery of Rap to pancreatic cancer cells. It is to note that pancreatic cancer overexpresses EGFR. The AuNP–GE11–Rap conjugates were successfully synthesized and characterized using physico-chemical techniques, which confirmed peptide conjugation and drug loading. In vitro studies using PANC-1 cells demonstrated …

Synteny To Snps: Comparative And Population Genomics Of Endemic Gila River Fishes, Alexander C. Cameron

Biology ETDs

Population genomic data are becoming an essential component of the best available science used by conservation professionals to make management decisions to preserve biodiversity in a rapidly changing world. The proliferation of high-throughput sequencing technologies has made generating genome scale data feasible for non-model organisms that are of conservation concern. In addition to applicability in conservation science, genomic data enable the exploration of basic questions related to species evolution. To that end, this body of research exemplifies the applied and basic utility of genomic data and is focused on two federally-protected minnows endemic to the Gila River basin, Loach Minnow …

Cv: Sarah Powers (Biology), Sarah Powers

Biology Department Faculty Curricula Vitae

No abstract provided.

Rab32c Mediates Osmoregulation And Calcium Homeoastasis In Dictyostelium Discoideum, Ashley Esparza

Theses and Dissertations

Vesicular trafficking is a fundamental process essential to cell viability and dictates roles in both cellular and tissue function in multicellular organisms. To further understand various vesicular trafficking processes, our lab focuses on the moderators of these processes, Rab GTPases, using the model organism Dictyostelium discoideum. This dissertation focuses explicitly on the uncharacterized protein Rab32C, a homolog of human Rab32. While several Rab family members have been well defined, the functionality of Rab32C remains poorly understood. This project investigated both the subcellular localization and functional role of Rab32C with biochemical, imaging, and molecular assays. Results from this study provide evidence …

Enviromental Dna (Edna) Tools For Invasive Mosquitofish (Gambusia Affinis) Surveillance At The Shoshone Pupfish (Cyprinidon Nevadensis Shoshone) Refugium, Yusuf Olamilekan Umar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spring-fed aquatic ecosystems of the North American Southwest and U.S. Great Basin hosts a plethora of endemic fish species due to the effects of hydrologic fragmentation that resulted from Pleistocene aridification. Threats to endemic fishes worldwide include human intentional or unintentional release of exotic species into their habitats. Early detection of invasive species, while corrective actions are still possible, is critical for management, yet traditional survey methods are often disruptive to sensitive ecosystems, costly, and limited in sensitivity. The recent development of environmental DNA (eDNA) approaches offers powerful alternatives for invasive species monitoring in aquatic systems. In this study, a …

Elucidating The Role Of Pbaf Chromatin Remodeling Subunit Arid2 In B Cell Development, Rachel Paolini

Arts & Sciences Graduate Student Theses and Dissertations

B cells are key components of the adaptive immune system that mediate humoral immunity through the production of antigen-specific antibodies. The generation of functional B cells involves multiple stages of differentiation across distinct anatomical niches, requiring precise regulation of microenvironmental signals and intrinsic transcriptional networks. SWI/SNF chromatin remodeling complexes have emerged as key regulators of B cell lineage commitment by modulating the accessibility of transcriptional programs required for differentiation and maturation. However, the specific roles of individual SWI/SNF subunits and distinct complexes within early B cell differentiation remain poorly understood. In this thesis, I investigated the function of Arid2, an …

Functional And Microbial Consequences Of Experimental Evolution Under Starvation In Drosophila Melanogaster, Kristal Marie Aguilar-Conger

UNLV Theses, Dissertations, Professional Papers, and Capstones

Previous studies in the Gibbs lab have shown that starvation resistant Drosophila melanogaster flies have increased lipid content, lower metabolic rates, and poor physiological health. Historically, many evolutionary studies end at the phenotypic level, leaving the genomic basis largely unresolved. Using Evolve and Resequence (E&R) study, we can map genome-wide allele-frequency trajectories under selection, linking phenotypic shifts to their genomic underpinnings. This study utilized the E&R approach to identify enriched biological processes and pathways underlying starvation adaptation in Drosophila melanogaster. Five replicate restart populations (RS A–E) selected for starvation resistance, along with a control (RC), were resequenced at Generations 1, …

Protocols For Antioxidant Testing: A Mini Review Of Common Assays And Approaches, Abdulsalam Halboup, Sameer A. Alkubati

AUIQ Complementary Biological System

Antioxidants play a pivotal role in mitigating damage caused by oxidative stress, which is implicated in aging, inflammation, neurodegeneration, and various chronic diseases. With the growing interest in natural and synthetic antioxidants across nutraceutical, pharmaceutical, and food industries, the need for reliable, reproducible, and standardized testing methods has become increasingly urgent. This mini-review provides a structured overview of the most widely used antioxidant testing protocols, categorized into in vitro chemical-based assays (e.g., DPPH, ABTS, FRAP, metal chelation), cell-based assays (e.g., DCFH-DA for intracellular ROS detection), and in vivo biomarker-based models. Each method’s principle, experimental protocol, advantages, and limitations are critically …

Prevalence Of Giardia Infection: A Cross-Sectional Study In Basra Province, Iraq, Sarah Kamal Naser

AUIQ Complementary Biological System

Giardiasis is a common parasite infection that is seen more frequently than any other parasitic infection worldwide. This infection is especially prevalent in tropical areas and in developing nations that have a poor standard of living and poor health conditions. The Giardia parasite is able to infect people of any gender, as it enters the body by the mouth, passes down the oesophagus, and finally reaches the stomach, where it is not negatively impacted by gastric acids. The goal of this study is to determine the extent to which patients who were treated at Al-Zubair General Hospital in Basra, Iraq, …

Functional Impact Of Single Nucleotide Polymorphism Rs4129009 (Ile775val) On Human Toll-Like Receptor 10, Audrey N. Koti

Biology Student Research

Toll-like receptors (TLRs) are a subclass of pattern recognition receptors within the

innate immune system that detect pathogen-associated and danger-associated molecular patterns,

thereby initiating host defense responses. The human TLR family comprises ten receptors (TLR1

– TLR10), each recognizing structurally conserved microbial motifs such as bacterial

lipoproteins and viral nucleic acids. The ligand specificities, adaptor protein recruitment, and

downstream signaling cascades have been well-characterized for TLR1 – TLR9, which

predominantly engage MyD88- or TRIF-dependent pathways to activate pro-inflammatory

transcription factors including NF-κB. In contrast, the ligand specificity and intracellular

signaling mechanisms of TLR10 have yet to be fully elucidated. Emerging …

Mental Health Literacy In Biology Graduate Teaching Assistants: Perception, Knowledge, And Training Needs In College Stem Education, Kanza Arshad, Ricardo Montoya, Nicole Scheuermann, Heather E. Bergan-Roller

Honors Capstones

College students experience a high prevalence of mental health challenges, and STEM students exhibit lower mental health literacy than students in other disciplines. Graduate Teaching Assistants (GTAs) play a crucial role in supporting undergraduate students, yet little is known about their mental health literacy (MHL) or how they navigate student disclosures in instructional settings. This preliminary study examines MHL among GTAs in biology, as well as their knowledge, perceptions, and training needs regarding MHL. We used semi-structured interviews and thematic analysis to examine how biology GTAs understand mental health, their responsibility related to student well-being, and what supports they identify …

Understanding Outer Membrane Vesicle Biogenesis In Bacteroides Thetaiotaomicron, Evan J. Pardue

Arts & Sciences Graduate Student Theses and Dissertations

Outer membrane vesicles (OMVs) are small proteoliposomes generated by active protrusion of the outer membrane (OM) in Gram-negative bacteria during growth. Over 60 years of experimentation has ascribed numerous functions to OMVs produced by different bacteria. However, the mechanism(s) by which OMVs are produced is poorly understood. Due to this, the field remains controversial because many regard OMVs as byproducts of cell lysis and question their physiological relevance. Previous studies in Pseudomonas aeruginosa and related species confirmed that these microbes undergo programmed cell death that results in the stochastic release of vesicles and cellular contents. On the contrary, Bacteroides spp. …

Genomics Insights Into The Biogeography And Evolution Of Galapagos Iguanas Using Radseq And Wgseq Techniques, Cecilia Paradiso

Theses and Dissertations

The Galápagos archipelago is known for its unique endemic fauna shaped by isolation and geological dynamism. This thesis explores the evolutionary history of Galápagos iguanas, a monophyletic group comprising the marine iguana (Amblyrhynchus cristatus) and three land iguanas: Conolophus marthae, C. pallidus, and C. subcristatus. These species differ in distribu- tion, population size, and conservation status, with C. marthae classified as Critically Endan- gered due to its restricted range and small population. The main goal of this thesis is to fill knowledge gaps concerning the evolutionary trajectories, demographic histories, and genetic var- iability of Galápagos iguanas. The first chapter reconstructs …

Mitochondrial Calcium Uniporter Regulates Itam-Dependent Platelet Activation, Jehiel Abigail Ajanel Gomez

Arts & Sciences Graduate Student Theses and Dissertations

Thromboembolic conditions are the leading cause of disability and death in the United States. Platelets play an important role in the pathophysiology of thrombus formation by aiding in the formation and stabilization of the clot. Central to platelet activation is cytoplasmic calcium, which increases after platelet activation through ITAM (Immunoreceptor tyrosine-based activation motif) or GPCR (G-protein-coupled receptor) receptors. Platelet mitochondria rely on cytoplasmic calcium for mitochondrial calcium influx, which is critical for ATP formation and regulation of mitochondrial reactive oxygen species. In other cells, mitochondrial calcium entry is regulated by the multimeric protein complex, mitochondrial calcium uniporter (MCU). Deletion of …

Spatiotemporal Ecology Of Mycobacterium Ulcerans And Mycolactone Functions In French Guiana And Southeastern United States Aquatic Environments, Magdalene Dogbe

Theses and Dissertations

Mycobacterium ulcerans, the causative agent of Buruli ulcer, produces mycolactone, a polyketide toxin traditionally studied for its role in human pathogenesis. This dissertation presents a comprehensive spatiotemporal analysis of M. ulcerans and mycolactone producing mycobacteria (MPM) ecology in the Americas and also reveals mycolactone's role in the environment as a microbial community regulator. Through comparative studies in French Guiana (endemic) and the southeastern United States (non-endemic), combined with experimental microcosm investigations, this research contributes to environmental pathogen ecology understanding. Environmental surveillance across 2,226 samples from French Guiana revealed complete MPM restriction to freshwater environments, with zero detections from 1,226 coastal …

Influence Of Urbanization On Diel Activity Patterns Across Seasons For Four Mesocarnivore Species Along An Urban-To-Rural Gradient Through Boston, Massachusetts, Myra M. Goes

Honors Program Theses and Projects

Urbanization is a growing threat to wildlife and poses unique challenges that animals must overcome to thrive in developed places. Temporal partitioning is one method that wildlife may employ to persist among the increased predation, competition, and human presence pressures of urban spaces. To evaluate diel patterns of mesocarnivores along an urban-to-rural (URG) gradient, data were utilized from camera traps established at 27 sites along a URG in southeastern Massachusetts as part of the Urban Wildlife Information Network (UWIN). Camera trap photos from summer and winter between 2023 to 2025 were used and filtered for coyote (Canis latrans), northern raccoon …

The Role Of Toll-Like Receptors In Tributyltin, Dibutyltin, And Pentachlorophenol Stimulation Of Tumor Necrosis Factor Alpha Production By Human Immune Cells, Latoya Michelle Daniel

Tennessee State University Alumni Theses and Dissertations

Tributyltin (TBT), Dibutyltin (DBT), and Pentachlorophenol (PCP) are persistent environmental contaminants that have been shown to increase immune-cell production of pro-inflammatory cytokines and thus have the capacity to cause chronic inflammation and its associated pathologies such as cancer, cardiovascular disorders, and autoimmune conditions. TBT has been detected in human blood at concentrations up to 260 nM, DBT up to 0.3 µM, and PCP between 0.15 and 5 µM. Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine produced by immune cells in response to pathogen- or damage-associated molecular patterns (PAMPs/DAMPs) via Toll-like receptors (TLRs). Dysregulated TNF-α production contributes to chronic inflammatory …

The Chemistry Of Color: A Comparative Analysis Of Natural And Synthetic Dyes In Textile Application, Caitlyn Pinaga Cpht

Honors Program Theses and Research Projects

The Chemistry of Color: A Comparative Analysis of Natural and Synthetic Dyes in Textile Application examines how color functions at the intersection of chemistry, culture, and environmental responsibility. This project traces the evolution of dyeing from ancient natural pigment traditions, rooted in ecological knowledge, agricultural practices, and cultural identity, to the industrial rise of synthetic dyes, whose laboratory precision enabled unprecedented consistency, brightness, and global textile expansion. Through experimental swatch analysis, the study compares the behavior of natural dyes derived from plants and food sources with modern fiber-reactive and synthetic dye classes on a range of fibers including cotton, bamboo …

Microplastic Exposure Alters Tubulin Leading To Alterations In Insulin Secretion By Pancreatic Beta Cells, Anakaren Garcia

Honors Program Theses and Research Projects

Abstract

Diabetes mellitus is a metabolic disorder characterized by elevated blood glucose levels due to impaired insulin secretion or diminished cellular response to insulin (resistance). Pancreatic β-cells depend on a well-organized cytoskeleton, particularly microtubules composed of α- and β-tubulin heterodimers, to transport insulin granules to the plasma membrane during glucose-stimulated insulin secretion (GSIS). Disruption of microtubule organization can impair granule trafficking and reduce insulin release. However, emerging environmental toxicants such as microplastics that interfere with β-cell cytoskeletal function remains largely unexplored.

Microplastics (MPs) are small plastic particles (< 5 mm) that have become widespread environmental contaminants and can enter biological systems. Previous studies have shown that MPs can induce cellular stress and protein misfolding, but their effects on microtubules in pancreatic β-cells are not well characterized. This study investigates whether exposure to fluorescent polystyrene microplastics alters microtubule organization and insulin secretion in βTC-6 cells.

βTC-6 cells were treated with 10 µg/mL of fluorescent polystyrene microplastics for …