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3,5-Dihydroxy-4-Isopropylstilbene (Tapinarof) Is A Partial Aryl Hydrocarbon Receptor Agonist In Fish, Conner A. Dicks

All Theses

The aryl hydrocarbon receptor (AHR) is a ligand activated transcription factor that is essential in regulating development, immune homeostasis, and drug and xenobiotic metabolism. Activation of the AHR by specific ligands results in its translocation to the nucleus where it induces a myriad of gene products, including cytochrome P450 (CYP) drug metabolizing enzymes (e.g., CYP1A1) and other components of the chemical defensome, as well as inflammatory control. Interestingly, the AHR can bind a wide variety of endogenous and xenobiotic ligands which are able to induce unique downstream effects dependent on cell type, inflammatory context, and ligand stability. The AHR is …

Trophic Roles And Climate-Driven Vulnerability For Benthic Invertebrates At Artificial Reefs In The Northern Gulf Of Mexico, Amanda Kirkland

LSU New Orleans Theses and Dissertations

Artificial reefs are deployed to enhance marine habitats and fisheries, yet their role in supporting secondary production and their vulnerability to climate stressors remain understudied. This dissertation investigates the trophic ecology and climate sensitivity of benthic invertebrates at artificial reefs in the northern Gulf of Mexico. Chapter 1 assessed reef food webs using stable isotopes from fishes, invertebrates, and primary producers across six reefs and two seasons. Mixing models showed that most fishes rely on benthic reef carbon, while suspension feeders consume plankton and sediment microphytobenthos. Isotopic niche analysis revealed functional diversity and seasonal shifts in δ¹³C and δ³⁴S, though …

Host-Virus Interaction Dynamics Using Sulfolobus Spindle-Shaped Virus And Host Sulfolobales System, Yeasin Ahmed

Graduate Theses and Dissertations

The Sulfolobus Spindle-shaped virus (SSV) is among the most studied archaeal viruses, particularly in extreme environments. This virus predominantly infects multiple Crenarchaea from the Sulfolobaceae family. These hosts thrive in extreme environmental conditions, such as sulfuric hot springs, with a pH of 2 to 4 and a temperature of 76-80˚C. Sulfolobales exhibit a wide geographical distribution across volcanic hot springs. The Sulfolobus Spindle-shaped Virus (SSV), encompassing strains such as SSV1 and SSV8, employs a non-lytic replication strategy in hosts belonging to the order Sulfolobales. The SSV-Sulfolobales system can be cultured in liquid and gellan gum solid media. A comprehensive study …

Microbial Guardians Of The Savannah: Unraveling The Gut Microbiome For African Carnivore Conservation, Laura E. Peirson

All NMU Master's Theses

Non-invasive fecal sampling is essential for wildlife gut microbiome (GMB) research, yet field conditions often limit preservation options. I compared gut bacterial communities in paired fecal samples preserved in stabilization tubes and air-dried in paper bags collected from anesthetized African lions (Panthera leo) and spotted hyenas (Crocuta crocuta) in Etosha National Park, Namibia. Additional opportunistic samples from carnivore kill sites were also analyzed. No significant differences in alpha or beta diversity were detected between preserved and dried samples, although bacterial beta diversity differed between preserved and opportunistic samples (PERMANOVA). Core bacterial communities remained consistent across sample …

Human Salivary Gland Stem/Progenitor Cells For Tissue Engineering, Sars-Cov-2 Susceptibility, And Neurointegration, Caitlynn Barrows

Dissertations and Theses (Open Access)

Salivary glands and the saliva they secrete are important for digestion, chewing, and maintaining oral health. Reduced saliva production leads to a decreased quality of life for patients experiencing hyposalivation as a result of disease or injury, thus a large effort has been dedicated to developing materials and medium to recapitulate the structure of the gland for regenerative medicine. In doing so, we have come closer to developing a more complex model to study disease. These models, however, do not yet fully recapitulate the gland. In this dissertation, we describe a new cell source that can be used to develop …

Saliva & Circadian Rhythm In Medical Profiling For Early Disease Prevention, Joseph Lewis

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Circadian rhythms affect almost every biological process from hormone secretion, gene expression, immune regulation, and metabolism. Studies show that disruption to these internal rhythms through irregular sleep, artificial sleep, and irregular sleep can significantly increase risk for chronic disease such as diabetes, cardiovascular disorders, neurodegeneration, and cancer. Saliva presents a viable alternative for capturing biomarkers found through blood or cerebrospinal fluid, offering substantial utility for diagnostic and chronobiological profiling. Saliva contains hormones such as cortisol and melatonin while containing inflammatory markers that fluctuate rhythmically throughout the day. Due to its ease of collection, saliva is well suited for longitudinal monitoring, …

Fluoride Toxicity And Benefit: An Integrated Review Of Mechanisms, Risks, And Public Health Impact, Sophia Chavarria

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Fluoride has long been praised for its role in preventing dental caries, primarily through its effects on enamel remineralization and antibacterial effects. However, growing evidence from molecular and cellular studies suggests that excessive fluoride exposure, especially during tooth development, can lead to dental fluorosis and systemic toxicity. This paper examines the biological mechanisms underlying fluoride-induced dental fluorosis, with a focus on stress responses in ameloblasts, oxidative damage, impaired autophagy, and disrupted protein processing. It integrates data from in vitro, in vivo, and human studies to evaluate the cellular thresholds at which fluoride shifts from therapeutic to toxic. Systemic risks, including …

Site Fidelity, Seasonality, Movement, And Fish Associates Of Sand Tigers Carcharias Taurus In North Carolina, Ara L. Mcclanahan

Electronic Theses and Dissertations

Sand tigers Carcharias taurus are mackerel sharks with a disjunct global distribution in tropical and temperate seas. In the northwest Atlantic, sand tigers migrate along the coast of the eastern United States from the Gulf of Maine to Florida and occupy structurally complex benthic habitats. The long-term, underwater camera installation, SharkCam, at Frying Pan Tower, off Cape Fear, North Carolina, USA, sits atop an expanse of hard bottom reef frequented by sand tigers. The citizen-science platform Spot A Shark USA (SAS USA) uses images of sand tigers to identify and track individuals. This study utilized image encounters from SAS USA …

Stress-Survival Pathway Genes In Colorectal Cancer: Crc Progression And Hispanic Disparities, Highlighting Mcm10 As A Potential Player, Urbashi Basnet

Open Access Theses & Dissertations

Despite advances in screening and treatment, colorectal cancer (CRC) remains a leading cause of cancer-related deaths in the U.S., with notable disparities across racial and ethnic groups. Hispanic populations face a disproportionate burden, underscoring significant differences in incidence and outcomes. This study examines the role of the Stress-Survival Pathway (SSP) in colorectal cancer (CRC), with a focus on addressing health disparities among Hispanic populations. Twenty-eight differentially expressed SSP genes identified from bioinformatic analysis were validated in CRC cell lines and cDNA arrays using qRT-PCR and tissue microarrays by immunohistochemistry. SSP genes were further analyzed in CRC tissues from Hispanic and …

Investigating The E74-Mediated Regulation Of A Gata Factor In Aedes Aegypti Mosquitoes, Jacklyn Marie Estrada

Open Access Theses & Dissertations

The mosquito species Aedes aegypti has a significant impact on public health as a vector for multiple pathogens. Its ability to transmit deadly diseases, including Yellow Fever, Dengue Fever, and Zika, emphasizes the urgency of understanding its reproductive biology. In female mosquitoes, reproductive success hinges on obtaining a vertebrate blood meal, which triggers vitellogenesis - the synthesis of yolk protein precursors (YPPs) necessary for egg development. Without a blood meal, female Ae. aegypti remain in a state of previtellogenic arrest, where the YPP gene vitellogenin (Vg) is repressed by a type of transcriptional factor, GATAr (AaGATAr) (Attardo et al., 2003). …

Spatial And Thermal Aspects Of The Ecology Of Three Sympatric Rattlesnakes In The Montane Northern Chihuahuan Desert, Joshua James Mead

Open Access Theses & Dissertations

To understand how animals coexist on the landscape, the individual aspects of a species life history must first be understood. Animals need to find locations that provide the resources they need to survive. Movement, microhabitats, and temperature can alter such areas where animals occur. Understanding animal movements provide important information on space use and microhabitats on the landscape. Ectothermic animals must acquiesce to ambient temperatures or use behavioral modifications to alter their body temperature. The ability to maintain suitable body temperature is essential for physiological function, reproduction, and ability to avoid predation. Research on the variation in a species ecology …

The Inside Scoop: Elucidating The Three-Way Relationship Between Schistosoma Mansoni, The Gut, And Vaccines, Mariam A. Mhanna

Biomedical Sciences Theses & Dissertations

Schistosomiasis is a neglected tropical disease that affects over 250 million people worldwide. This blood fluke infection burdens communities and areas with limited to no access to clean fresh water. When a host is exposed to cercariae, the infectious agent, in a body of water, it matures in the host’s circulation into adult female and male worms. Copulated adult worms migrate to the mesentery, in the case of Schistosoma mansoni, and produce eggs that can cross the intestinal barrier and get excreted in the feces to continue the lifecycle. The effects of S. mansoni infection on the host …

Assessment Of Floral Resources From Three Tamaulipan Thornscrub Communities Of The Lower Rio Grande Valley, Gracie Makenna Granados

Theses and Dissertations

The Tamaulipan thornscrub is a transition zone between the neotropics and the temperate regions, harboring high biodiversity. This habitat supports a diverse insect community, including many pollinators of native and cultivated plants in Texas and northeastern Mexico. This ecosystem has been extensively degraded and lost; only 5% of its original cover remains north of the Rio Grande. Restoration of the Tamaulipan thornscrub has been ongoing for over three decades, but the important roles of pollinators in the success of such efforts and the functioning of the restored ecosystem have rarely been considered in restoration efforts. The purpose of this study …

Opa1-Mediated Mitochondrial Dynamics In Myogenic Differentiation Of C2c12 Myoblasts, Daniel Eloy Bazan

Theses and Dissertations

Mitochondria play a pivotal role in metabolic energy production, cellular signaling, and apoptosis. To carry out these key cellular roles, mitochondria dynamically balance their organization through opposing including fusion and fission processes. The balance between mitochondrial fusion and fission is regulated by key proteins such as OPA1 (optic atrophy 1) and OMA1 (overlapping activity with metalloprotease). More recently, mitochondria have been increasingly revealed to play key roles in cellular differentiation, where metabolic demands are reprogrammed. This study aims to elucidate the specific roles of OPA1 and OMA1 in the differentiation of C2C12 myoblast cells into myotubes.

Our data demonstrates that …

Phenotypic Plasticity In Response To Abiotic Factors In Silverleaf Nightshade (Solanum Elaeagnifolium), And The Effectiveness Of North American Lacebug (Gargaphia Arizonica Drake And Calvo) As A Biocontrol, Marco Andre Silguero

Theses and Dissertations

Silverleaf nightshade (Solanum elaeagnifolium) is a widespread invasive weed in South Texas and other arid regions, where it reduces crop productivity, competes with native vegetation, and resists conventional control methods. Its ability to thrive across different environments is linked to phenotypic plasticity, allowing it to adjust growth and physiology in response to light and water availability. In this thesis, I examine the role of plasticity in S. elaeagnifolium under field conditions and evaluate the potential of the North American lacebug (Gargaphia arizonica) as a biological control agent. Field observations were used to measure plant traits such as height, stem thickness, …

Investigating The Multiple Enzyme Complex In The Carotenoid Biosynthesis Pathway, Mercy Mormor

Electronic Theses and Dissertations

In nature, plant carotenoids are 40-carbon isoprenoids with polyene chains that may have double bonds. They are vital components of all photosynthetic organisms, playing several roles in the plant cell, including photosynthesis, pigmentation, phytohormone synthesis, signaling and photoprotection. In this study, we investigated protein-protein interactions among key enzymes involved in the carotenoid biosynthesis pathway using the Bimolecular Fluorescent Complementation (BiFC) assay. Our results revealed several interactions that suggest a coordinated regulation of enzymatic activity within this pathway, highlighting potential regulatory complexes that influence carotenoid production. The study also highlights the pivotal role of Zeta-Carotene Isomerase (Z-ISO) as a key regulatory …

Gut Passage Time In Small Mammals: Influences Of Small Mammal Traits, Digesta Phase, And Particle Morphology, Noah G. Hale

Electronic Theses and Dissertations

Dispersal is crucial in maintaining healthy ecosystems, but little is known about mechanisms influencing fungal spore dispersal by animals. We aimed to develop a more mechanistic understanding of the influence of fungal spore traits and small mammal traits on gut retention time. We fed three species of small mammals (shrew, mouse, vole), which differ in gut morphologies, digestive strategies, and activity a combination of markers including: liquid digesta phase (CrEDTA), small particle (fungal spores with diverse morphologies), and large particles (glitter and beads, representing plant cells and seeds, respectively). We found that hindgut fermenters selectively retained the liquid markers, spores …

The Effects Of Temperature And Cardiotonic Steroids On Cardiac Function And Metabolism In Snakes, Hannah Wilson

All Graduate Theses and Dissertations, Fall 2023 to Present

The function of the heart provides a window into the physiology of vertebrates and a means of evaluating their response to the stresses imposed by diverse activities. I developed a miniaturized instrument to record electrocardiograms (ECGs), using open-source Arduino technology, that a snake can wear as a backpack. The backpack can also be used when the snake is in a metabolic chamber, to record the metabolic rate and ECG simultaneously. I first used the ECG backpack to record the physiology of snakes under different temperature conditions, to verify that the system worked as expected. the backpack was then used on …

Improved Autofluorescence Lifetime Decay Analysis For Identification Of Cellular Autofluorescence Biomarkers For Label-Free, Single-Cell Assessment Of Mitochondrial Membrane Potential, Olivia Isabel Kolenc

Graduate Theses and Dissertations

Optical imaging of metabolism using the autofluorescence of the metabolic cofactors NADH, NADPH, and FAD has a wide range of sensitivities and the capability to collect a great deal of metabolic information. Multiphoton microscopy (MPM) is a non-invasive, label-free optical imaging technique capable of performing fluorescence lifetime imaging (FLIM) using time correlated single photon counting (TCSPC). However, autofluorescence FLIM presents a challenge in collecting sufficient photons to provide adequate signal to noise ratios (SNR) for analysis. Additionally, the specificity of autofluorescence biomarkers of metabolism has not been well-defined. Contextualizing these autofluorescence measures using established functional biomarkers can improve interpretability of …

Mixture Effects On Metal Accumulation In The Asian Clam, Corbicula Fluminea, Mark A. Huff

Electronic Theses and Dissertations

Field collected Corbicula fluminea were exposed to trace level copper, lead, and zinc with the aim of examining the preferential accumulation between the soft tissue and shell. Metal levels were based on those in a permitted industrial effluent. At 1X effluent and 2X effluent exposure levels, copper was found to preferentially accumulate in the clam soft tissue, lead was found to preferentially accumulate in the clam shell, and zinc was found to excrete back into the diluent after preferentially accumulating in the clam soft tissue. When exposed as a mixture at 1X effluent levels, copper and lead were found to …

Isolation And Characterization Of Siderophore(S) From Pseudomonas Mosselii, Casey J. Stophel

Electronic Theses and Dissertations

Iron is essential for growth of most microorganisms. It functions as an important cofactor in many important biological processes. However, iron found in soil is rendered insoluble and unavailable to microorganisms for use. To overcome this, many bacterial species produce siderophores, a small organic molecule that has high affinity for iron. Siderophores allow for bacterial cells to obtain otherwise insoluble iron. Pseudomonas mosselii, a Gram negative bacterium, was isolated from a local soil sample. P. mosselii was found to produce siderophore(s) under iron restricted environment, however, they have not been characterized. Therefore, it was of interest to isolate, purify and …

Investigating The Impact Of Psychoactive Plant Alkaloids On Bumblebee Behavior, Skylar Mathieson

Electronic Theses and Dissertations

The relationship between plants and their pollinators is often framed as a food-for-service exchange in which plants provide pollinators with nutrients in exchange for transport of their gametes. However, in addition to essential nutrients, many floral rewards (nectar, pollen) also contain defensive toxins such as alkaloids, with largely unexplored consequences for plant-pollinator interactions. I investigated how three psychoactive and addictive plant alkaloids — caffeine, nicotine, and morphine — affect foraging behavior in generalist bumblebees (Bombus impatiens) using robotic flowers. Each of these chemicals affected pollinator foraging behavior, influencing the number and duration of their visits to flowers in …

Small Stream Restoration In The Piedmont Of South Carolina: Comparison Of Evaluation Tools And Water Quality’S Effects On Salamanders, Camryn Lachica

All Theses

For many years, the United States Army Corps of Engineers (USACE) used the Guidelines for Preparing a Compensatory Mitigation Plan worksheets to guide pre-restoration evaluation and determine post-restoration mitigation credits in South Carolina. Recently, the USACE in South Carolina transitioned to the Stream Quantification Tool (SQT), which provides a more comprehensive assessment framework. Our first objective was to compare these assessment methodologies across different landscape types to determine what the SQT adds to mitigation calculations that were not considered in prior worksheets. We evaluated 16 streams in the Piedmont of South Carolina, with four replicates each of forested, suburban, urban, …

Activation And Suppression Mechanisms Of The Nrg1 Helper Nlrs, Yu-Ru Wang, Ruize Zhang, Daowen Wang, Yong Wang, Zheng Qing Fu

Faculty Publications

No abstract provided.

Impact Of S-Phase Kinase Protien 2 Blockades On Hematopoetic Stem Cell Metabolism, Nicole Elmaraghy

Electronic Theses, Projects, and Dissertations

Hematopoietic stem and progenitor cells (HSPCs) quiescence is vital for the success of bone marrow transplantation, as it preserves long term self- renewal and prevents premature exhaustion (Takubo et al., 2013; Wilson et al., 2008). However, bone marrow transplant (BMT) failure remains a clinical challenge, often due to lack of long-term engraftment and insufficient stress reliance. Both of these characteristics are tightly linked to disrupted stem cell quiescence and metabolic imbalance (Anso et al., 2017; Vannini et al., 2016). One key player is S-phase kinase protein (SKP2), an E3 ubiquitin ligase that targets cell cycle inhibitors, like p27, for proteosome …

Night-Time Warming And Prey Availability Interact To Influence Physiology In Prairie Lizards (Sceloporus Consobrinus), Allison R. Litmer, Morgan K. Pelley, Steven J. Beaupre

Biological Sciences Faculty Publications and Presentations

Among ectotherms, temperature and food availability are drivers of individual and population characteristics. Increasing night-time temperatures due to climate change can increase energetic demands, potentially amplified or mitigated by prey consumption. Few studies examine night-time temperatures specifically, and consequences of co-occurring changes in the abiotic and biotic environment. Thus, we examined interactions between warming night-time temperatures and prey availability (as a proxy of foraging time and effectiveness), and how they affect food consumption, digestive passage time, metabolizable energy intake (MEI), assimilated energy, and fecal and urate production in a model organism, prairie lizards (Sceloporus consobrinus). Three temperature treatments (current conditions, …

The Role Of The Jnk Gene In Ovarian Cancer Inflammatory Pathways, Tashoy D. Campbell

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Ovarian cancer, one of the leading causes of cancer-related deaths in women globally, presents a significant challenge due to its common late-stage diagnosis and chemoresistance (inability of the tumor to respond to drugs). The c-Jun N-terminal kinase (JNK) signaling pathway plays a crucial role in ovarian cancer progression, contributing to inflammation, tumor survival, metastasis, and chemotherapy resistance. This literature review examines the role of the JNK signaling pathway in ovarian cancer, with a focus on its role in inflammation, metastasis, and chemoresistance. JNK regulates key inflammatory cytokines, such as TNF-α and IL-6, which promote tumor growth and immune evasion. Moreover, …

Use Of Infrared Spectroscopy In Animal Studies: Aspects Of Health Science, Brian Manzanares

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Non-invasive imaging technologies, such as infrared thermography (IRT), near-infrared spectroscopy (NIRS), and fourier-transform infrared spectroscopy (FTIR) are revolutionizing the field of animal research by enabling real-time, stress-free assessment of physiological conditions. Such methods like these are align with the ethical standards of the 3Rs, replacement, reduction, and refinement-by reducing the need of invasive procedures while enhancing data quality and animal welfare. These methods can also provide critical insight into animal health, behavior, and stress responses without the need for invasive procedures or restraint, thereby minimizing harm and distress. This literature review will explore the practical applications of IRT, NIRS, and …

The Role Of Nicotine In Treating Neurodegenerative Diseases, Jacquelyn T. Deaton

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Neurodegenerative diseases have emerged as a critical medical challenge because they cause progressive neuronal death alongside structural or functional deterioration. Families, healthcare institutions, and affected individuals face significant challenges due to neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's diseases, which impair both cognitive function and motor abilities. Researchers have found that nicotine in tobacco products is a compound with therapeutic potential. This literature review explores how nicotine interacts with neurodegenerative mechanisms, such as oxidative stress and inflammation, and assesses its potential neuroprotective effects in conditions like Alzheimer's and Parkinson's diseases. In the central nervous system, nicotine binds to the …

Resolving Intra-Tumoral Heterogeneity Of Breast Cancer Using Single-Cell Multi-Omics, Yun Yan

Dissertations and Theses (Open Access)

Breast cancer is a highly heterogeneous disease characterized by diverse genetic, transcriptional, and epigenetic landscapes. Understanding how intra-tumoral heterogeneity (ITH) influences therapeutic response and drives tumor evolution remains a central challenge in cancer biology. Here, we leverage single-cell multi-omics technologies to dissect the cell states and gene expression programs underlying breast cancer heterogeneity, with a focus on triple-negative breast cancer (TNBC) and estrogen receptor-positive (ER+) breast cancer.

In the first part, we applied single-cell RNA sequencing and spatial transcriptomics to profile over 400,000 cells from 101 treatment-naïve TNBC patients. We identified 4 archetypes at the patient level and 13 metaprograms …