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Exploring Resilience With Neuroimaging: Moderators Of The Impacts Of Childhood Traumatic Stress On Fear Processing., Karisa June Hunt May 2024

Exploring Resilience With Neuroimaging: Moderators Of The Impacts Of Childhood Traumatic Stress On Fear Processing., Karisa June Hunt

Electronic Theses and Dissertations

Childhood trauma is an alarming public health crisis, and the field of trauma research is relatively underdeveloped given population rates of childhood trauma and post-trauma pathology. Even less studied than the impacts of trauma are the impacts of resilience, and the protective factors that foster it. It is widely acknowledged that an investigation of trauma is incomplete without an investigation of its impacts on fear processing. Understanding the neural underpinnings of resilience to childhood trauma during fear conditioning is vital to the development of therapeutic interventions able to moderate its devastating impacts. The present study investigated the complex neurobiological interplay …


Investigation Of Avaren-Fc's Therapeutic Potential Against Ovarian Cancer., Katarina Lee Mayer May 2024

Investigation Of Avaren-Fc's Therapeutic Potential Against Ovarian Cancer., Katarina Lee Mayer

Electronic Theses and Dissertations

This thesis describes the investigation of Avaren-Fc (AvFc), a novel lectin-based therapeutic fusion protein consisting of the recombinant Avaren lectin and the Fc region of human IgG1, against ovarian cancer. AvFc possesses selectivity toward tumor associated N-linked high-mannose-type glycans. The present study demonstrates AvFc’s in vitro activity against OVCA cell lines via antibody-dependent cell-mediated cytotoxicity and its ability to extend the survival of mice challenged with murine ID8 OVCA cells after repeated systemic administration. Furthermore, AvFc treatment in this model was found to increase the presence of peritoneal leukocytes, suggesting a shift toward an improved antitumor immune response. Another key …


Multithreaded Applications On The Heterogeneous Research Computing Environment., Sungbo Jung May 2024

Multithreaded Applications On The Heterogeneous Research Computing Environment., Sungbo Jung

Electronic Theses and Dissertations

Bioinformatics is a domain that has experienced rapid research growth in recent years, as evidenced by the increasing number of articles in biomedical databases such as PubMed, which adds over a million publications every year. However, this also poses a challenge for researchers who need to find relevant citations for their work. Therefore, developing efficient indexing and searching methods for text data is crucial for Bioinformatics. One key technique for information retrieval is document inversion, which involves creating an inverted index to enable efficient searching through vast collections of text or documents. This Ph.D. research aims to design the research …


An Investigation Into The Structural Features That Control Factor Xiii Stability And Substrate Specificity., Rameesa Darul Amne Syed Mohammed May 2024

An Investigation Into The Structural Features That Control Factor Xiii Stability And Substrate Specificity., Rameesa Darul Amne Syed Mohammed

Electronic Theses and Dissertations

Factor XIII (FXIII) is a transglutaminase enzyme with multiple physiological roles that is found in plasma and cells of bone marrow origin. The catalytic A subunit (FXIII-A) is made of an N-terminal activation peptide (AP), β-sandwich, catalytic core, and two β-barrel domains. FXIII crosslinks the sidechains of glutamine (Q) and lysine (K) residues across plasmatic and cellular substrates. Because of its involvement in clot stabilization and determining fibrin clot size, FXIII-A is regarded as a target for developing new anticoagulants with minimal bleeding risks. However, the FXIII-A structural features that control its stability and substrate specificity largely remain unknown. Plasma …


Anthropogenic Litter In Urban Waterways: An Analysis Of Litter, Urbanization, And The Emerging Role Of Citizen Science In Beargrass Creek, Louisville, Ky., Ella Swigler May 2024

Anthropogenic Litter In Urban Waterways: An Analysis Of Litter, Urbanization, And The Emerging Role Of Citizen Science In Beargrass Creek, Louisville, Ky., Ella Swigler

Electronic Theses and Dissertations

This thesis addressed the ever growing presence and persistence of anthropogenic litter (AL) in urban waterways. AL has been studied in marine environments, but research gaps exist in riverine ecosystems. Most of the AL that reaches the Earth’s oceans is carried by urban rivers, so understanding the relationship between these waterways and AL is critical in effectively fighting AL accumulation, especially for legacy plastic pollutants. The study explored fifteen sites throughout Beargrass Creek and recorded the quantity and type of AL present throughout the summer and fall of 2023. The National Geographic Marine Debris Tracker App was employed to successfully …


Do American Bison Practice Democracy? Group Consensus Decision Making Drives Bison Herd Movements And Cohesion., Matthew Sapien May 2024

Do American Bison Practice Democracy? Group Consensus Decision Making Drives Bison Herd Movements And Cohesion., Matthew Sapien

Electronic Theses and Dissertations

The American bison is an iconic mammal that lives in large social herds and is considered a threatened species. Little is known about how bison make decisions as a group, whether through despotic individuals or group consensus. In this dissertation, I researched the mechanisms bison use to make herd movement decisions in 3 herds in the United States. In chapter one I examined the number of bison that participated in voting events for herd movement decisions and whether the final movement decision matched the direction with the most votes. Bison herd movements did match the direction with the most adult …


Relationships Between Fitness Levels, Physical Activity Participation, Hemoglobin A1c Levels, And Motor Proficiency In Adolescent Patients With Type 1 Diabetes., Caroline E. Frye May 2024

Relationships Between Fitness Levels, Physical Activity Participation, Hemoglobin A1c Levels, And Motor Proficiency In Adolescent Patients With Type 1 Diabetes., Caroline E. Frye

Electronic Theses and Dissertations

Physical activity is a critical component of a healthy lifestyle and can lead to improved fitness levels and blood glucose management, as well as decreased HbA1c levels. PURPOSE: The purpose of this study was to determine if there are relationships between cardiorespiratory fitness, muscular strength, muscular endurance, flexibility, body composition, physical activity participation, hemoglobin A1C levels, and motor proficiency in adolescent patients with T1D. METHODS: Pediatric patients with a diagnosis of T1D enrolled in a sports medicine program were invited to participate in this study. Retrospective clinical chart reviews were conducted to determine participant’s sociodemographic and anthropometric measures and most …


Assessing Sustainability Within The Brewing Industry: A Literature Review And Benchmarking Analysis., Elijah Thomas Miller May 2024

Assessing Sustainability Within The Brewing Industry: A Literature Review And Benchmarking Analysis., Elijah Thomas Miller

Electronic Theses and Dissertations

The goals of this study were twofold: to further examine sustainability within the brewing industry through a literature analysis across four academic journals, and a benchmarking analysis of a Louisville, Kentucky brewery’s resource consumption and emissions production. Publications related to the brewing industry were examined for the presence of sustainability keywords: “efficiency, sustainability, carbon footprint, climate change and greenhouse gas”. Benchmarking examined the local brewery’s primary production facility to determine their performance compared to other surveyed breweries pursuing sustainability across the country. Literature examination found noticeable discrepancies between the appearance of sustainability topics within article abstracts and their discussion within …


Inhibition Of Pro-Inflammatory Lipid Mediators By Yersinia Pestis., Amanda Brady May 2024

Inhibition Of Pro-Inflammatory Lipid Mediators By Yersinia Pestis., Amanda Brady

Electronic Theses and Dissertations

Yersinia pestis causes the human disease known as plague. A key manifestation of plague is a delayed inflammatory response. Because this delay in inflammation is required for virulence, I was interested in defining the molecular mechanisms used by Y. pestis to evade immune recognition. Eicosanoids are produced early during infection and necessary to initiate a rapid inflammatory response. Despite the importance of these lipids in mediating inflammation, the role of eicosanoids during plague has not been previously investigated. Using an intranasal mouse model infection, I determined the kinetics of eicosanoid synthesis during pneumonic plague. I further demonstrated that LTB4 …


Biocargos: Capture And Release Gels For Optimized Storage Of Biologics., Chinmay Shashank Potnis Dec 2023

Biocargos: Capture And Release Gels For Optimized Storage Of Biologics., Chinmay Shashank Potnis

Electronic Theses and Dissertations

No abstract provided.


The Impact Of Environmental Pollutants On Alcohol-Associated Liver Disease Pathogenesis., Tyler Charles Gripshover Dec 2023

The Impact Of Environmental Pollutants On Alcohol-Associated Liver Disease Pathogenesis., Tyler Charles Gripshover

Electronic Theses and Dissertations

Steatotic liver disease is brought upon by differing etiologies and its global prevalence is expected to keep increasing over the next several decades. Particularly, alcohol-associated liver disease (ALD) manifests from excessive alcohol consumption where the liver retains lipids and progresses with metabolic dysfunction. Previous studies have demonstrated that environmental pollutants, polychlorinated biphenyls (PCBs) promote metabolic dysfunction associated steatotic liver disease (MASLD), in diet-induced obesity models. However, it is unknown if environmental pollutants may also promote ALD pathogenesis. Thus, this dissertation focuses on characterizing the effects of PCB126 in a rodent ALD model followed by multiple ‘Omics approaches to identify mechanisms …


Study Of The Effects Of Chronic Cadmium Exposure On The Pathogenesis Of Pulmonary Arterial Hypertension., Dakotah Dominique Cathey Dec 2023

Study Of The Effects Of Chronic Cadmium Exposure On The Pathogenesis Of Pulmonary Arterial Hypertension., Dakotah Dominique Cathey

Electronic Theses and Dissertations

We reported pulmonary artery hypertension (PAH) patients had elevated levels of Cd in both blood and urine, therefore, this study tested whether Cd directly induces PAH or facilitates PAH pathogenesis in mouse models. C57/6J mice were initially exposed to drinking water with or without 5ppm Cd for 8 weeks. Then, half the mice in both control and Cd groups were given SU5416 and hypoxia (SuHx) for 4 weeks to induce PAH, resulting in 4 subgroups: Control, Cd, PAH, and Cd+PAH. Diastolic and systolic functions of the left and right ventricles (LV, RV) were examined with echocardiography before and after PAH. …


The Interplay Between Lung Adenocarcinoma, Nutrient Availability, And The Microbiome., Alexis A. Vega Dec 2023

The Interplay Between Lung Adenocarcinoma, Nutrient Availability, And The Microbiome., Alexis A. Vega

Electronic Theses and Dissertations

Lung cancer is one of the most common forms of cancer diagnosed, and has the highest lethality rate across all other forms of cancer in the U.S. While current therapeutic options include chemo-, immuno-, and radio-therapy, the benefits of caloric or nutrient restriction on cancer cells has also been investigated. Due to the many biological functions associated with methionine, many have proposed a methionine restricted diet would lead to favorable outcomes when combating cancer. Although our cells are incapable of synthesizing methionine, the bacteria found in our microbiome can. Furthermore, recent discoveries suggest an independent microbiome found within tumors that …


Effects Of A Protection Zone In A Reaction-Diffusion Model With Strong Allee Effect., Isaac Johnson Dec 2023

Effects Of A Protection Zone In A Reaction-Diffusion Model With Strong Allee Effect., Isaac Johnson

Electronic Theses and Dissertations

A protection zone model represents a patchy environment with positive growth over the protection zone and strong Allee effect growth outside the protection zone. Generally, these models are considered through the corresponding eigenvalue problem, but that has certain limitations. In this thesis, a general protection zone model is considered. This model makes no assumption on the direction of the traveling wave solution over the Strong Allee effect patch. We use phase portrait analysis of this protection zone model to draw conclusions about the existence of equilibrium solutions. We establish the existence of three types of equilibrium solutions and the necessary …


Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil Dec 2023

Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil

Electronic Theses and Dissertations

Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …


Using A Toxic Aging Coin To Assess Hexavalent Chromium-Induced Neurotoxicity., Samuel Thomas Vielee Dec 2023

Using A Toxic Aging Coin To Assess Hexavalent Chromium-Induced Neurotoxicity., Samuel Thomas Vielee

Electronic Theses and Dissertations

We are facing an aging crisis, with 20% of the U.S. population projected to be geriatric (65+) by 2030 and live another 40+ years. Age-related diseases accompany a growing geriatric population, emphasizing the need to understand their etiology. Environmental pollutants compound this crisis by: 1) geriatrics are more susceptible, exacerbating age-related diseases and comorbidities, and 2) they accelerate biological aging, inducing age-related diseases at younger ages. We address this crisis using a ‘toxic aging coin’ approach; heads examines how age impacts toxicity, tails examines how chemicals accelerate aging. This thesis applies the heads side for Cr(VI)-induced neurotoxicity across ages. We …


The Role Of E-Liquid Constituents In E-Cigarette-Induced Cardiac Arrhythmia And Autonomic Imbalance., Cory Kucera Aug 2023

The Role Of E-Liquid Constituents In E-Cigarette-Induced Cardiac Arrhythmia And Autonomic Imbalance., Cory Kucera

Electronic Theses and Dissertations

Introduction. Accumulating evidence indicates that exposure to electronic cigarettes (e-cigs) promotes sympathetic dominance and electrophysiologic instability in the heart, potentially culminating in arrhythmogenesis. E-liquids contain various formulations of nicotine and flavorings, but the effects of specific e-liquid constituents and their concentrations on e-cig-induced autonomic imbalance and electrical dysfunction are unresolved. To that end, we tested the hypothesis that e-cigs modify cardiac autonomic balance and ventricular arrhythmogenesis in mice dependent on e-liquid constituent type and concentration. Methods. Using a crossover design and a serial exposure regimen, ECG-telemetered male C57BL/6J mice underwent whole-body exposure to e-cig aerosols generated from e-liquids containing different …


Tropical Understory And Canopy Twig Ants (Pseudomyrmex): Natural History, Sensory Homing, And Neuroecology., Daniella Prince Aug 2023

Tropical Understory And Canopy Twig Ants (Pseudomyrmex): Natural History, Sensory Homing, And Neuroecology., Daniella Prince

Electronic Theses and Dissertations

In this dissertation, I examined the behavior of foraging twig ants, explored the sensory profile of their homing behavior, and investigated the role of habitat use in shaping the sensory neurobiology of species within the genus Pseudomyrmex (Hymenoptera: Formicidae). In chapter one, I reviewed the ecology of Pseudomyrmex, and introduced the focal species, P. boopis, a neotropical understory-dwelling twig ant. In chapter two, I described the natural history of P. boopis on Barro Colorado Island, Panama—specifically, their nesting habits, activity rhythm, and foraging behavior on understory surfaces. Pseudomyrmex boopis colonies were diurnal and nested in dead twigs in …


Illuminating Underappreciated Mechanisms Of Receptor Regulation In Human Lymphocytes., Cassandra Woolley Aug 2023

Illuminating Underappreciated Mechanisms Of Receptor Regulation In Human Lymphocytes., Cassandra Woolley

Electronic Theses and Dissertations

A thorough understanding of receptor regulation is imperative to predict expression in varying contexts of disease or treatment. Lymphocyte surface receptors are often used as biomarkers and drug targets, making them particularly important for study. For receptors of debated functionality, such as the Fc receptor for IgM (FcMR), understanding regulation can also help to predict expression in vivo to supplement hypotheses of biological roles. Various mechanisms exist for altering receptor surface expression, including direct feedback mechanisms such as ligand-induced endocytosis and broader mechanisms such as transcriptional and translational control. In this dissertation, we explore selected underappreciated mechanisms of lymphocyte receptor …


Novel Insights Into Oligodendrocyte Biology From Developmental Myelination Studies In Autophagy Deficient Mice And Analysis Of Oligodendrocyte Translatome Response To Contusive Spinal Cord Injury., Michael David Forston Aug 2023

Novel Insights Into Oligodendrocyte Biology From Developmental Myelination Studies In Autophagy Deficient Mice And Analysis Of Oligodendrocyte Translatome Response To Contusive Spinal Cord Injury., Michael David Forston

Electronic Theses and Dissertations

Loss of myelin causes severe neurological disorders and functional deficits in white matter injuries (WMI) such as traumatic spinal cord injury (SCI). This dissertation is focused on autophagy in OL development and the OL translatome after SCI. Chapter I describes the history of myelin, OL development, and their involvement in neurodegenerative diseases and SCI. The proteostasis network, in particular autophagy, and its contributions to white matter pathology is discussed. It concludes examining advantages and disadvantages of unbiased omics tools, like RiboTag, to study transcriptional/translational landscapes after SCI. Chapter II focuses on autophagy in OPC/OL differentiation, survival, and proper myelination in …


Epitranscriptomic Regulation In Breast Cancer And Pcb-Induced Liver Disease., Belinda Petri Aug 2023

Epitranscriptomic Regulation In Breast Cancer And Pcb-Induced Liver Disease., Belinda Petri

Electronic Theses and Dissertations

Post-transcriptional RNA modifications including N6-methyladenosine (m6A) regulate mRNA stability, splicing, and translation. My research examined m6A in two disease models: breast cancer (BCa) and non-alcoholic fatty liver disease (NAFLD). Acquired resistance to endocrine therapies (ET) develops in approximately 20% of BCa patients with estrogen receptor α positive (ER+) tumors following treatment. The mechanisms by which tumor cells evade ET are not completely understood. Using a cell line model, we investigated the role of an m6A reader protein, HNRNPA2B1 (A2B1) that is upregulated in ET-resistant ER+ BCa cells. Stable overexpression of A2B1 in ET-sensitive MCF-7 cells (MCF-7-A2B1), results in ET resistance, …


New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly Aug 2023

New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly

Electronic Theses and Dissertations

Dryolestoids are extinct cladotherians mammals from the Jurassic and Cretaceous periods. I describe a collection of dryolestoid specimens from the Late Cretaceous localities of Cerro Tortuga (Allen Formation), Anfiteatro 1, and Shining (both La Colonia Formation) from Patagonia, Argentina. Using comparative morphology, I identify a new species of meridiolestidan dryolestoid based on eleven specimens across both formations. The new species’ recovery from La Colonia Formation represents the first dryolestoid connection between the two approximately contemporaneous formations. The species’ morphology may represent an ecological shift within Meridiolestida from insectivory to herbivory, showing a transition in characters between the plesiomorphic sharp-toothed meridiolestidans …


Measurement Of Conduction, Radiation, And Convection Thermal Energy To Assess Baking Performance In Residential Ovens., Sean Simpson Aug 2023

Measurement Of Conduction, Radiation, And Convection Thermal Energy To Assess Baking Performance In Residential Ovens., Sean Simpson

Electronic Theses and Dissertations

Residential ovens are complicated thermal environments capable of delivering convection, conduction, and radiation heat transfer to food. The amount and mode of heat transfer can change based on the design of the oven cavity, cooling systems, and oven cycle algorithms. Studies have shown that the changes in one heat transfer mode can have an impact on the quality of baked goods. The many variables involved make designing residential ovens a time consuming and costly process. The goal of this study is to adapt thermal energy sensing technology to collect energy data from a residential oven and develop correlations to quality …


Fbg Αc 389 – 402 Modulates Factor Xiii Crosslinking In The Fibrinogen Αc Region., Francis Dean Orlina Ablan Aug 2023

Fbg Αc 389 – 402 Modulates Factor Xiii Crosslinking In The Fibrinogen Αc Region., Francis Dean Orlina Ablan

Electronic Theses and Dissertations

Fibrinogen (Fbg) is a coagulation protein critical for clot formation. Coagulation Factor XIII (FXIII) is a calcium-dependent transglutaminase that crosslinks reactive glutamines (Q) and lysines (K) between fibrin and other anti-fibrinolytic proteins. In the presence of Ca2+, FXIII could be activated non-proteolytically (FXIII-A°), or proteolytically by thrombin (FXIII-A*). Significant increases in clot stability and red blood cell retention are linked to FXIII activity in the fibrinogen αC region (Fbg Aα 221 – 610). This region contains several FXIII-reactive glutamines and lysines, as well as a binding site for FXIII-A* (Fbg αC 389 – 402) that includes a key …


Effects Of Environmental Pollutants On Liver Disease: Role Of The Gut-Liver Axis., Ngozi Victoria Adiele Aug 2023

Effects Of Environmental Pollutants On Liver Disease: Role Of The Gut-Liver Axis., Ngozi Victoria Adiele

Electronic Theses and Dissertations

Polychlorinated biphenyls (PCBs) and polystyrene (PS) microplastics are environmental pollutants associated with various diseases including toxicant associated fatty liver disease (TAFLD). Previously, exposure to Aroclor 1260 (a PCB mixture) has been shown to exacerbate TAFLD, partly through Aroclor 1260 induced gut dysbiosis. Studies has also demonstrated that PS exposure alters gut microbiome composition and induced obesity. However, the effects of Aroclor 1260 on the gut and the effects of PS on the liver are still understudied. Therefore, we hypothesize that environmental pollutants will disrupt the gut-liver axis through changes in gut and its microbiome as well as changes in liver …


Characterization Of The Immunoglobulin Lambda Chain Across Diverse Human Populations., William Gibson Aug 2023

Characterization Of The Immunoglobulin Lambda Chain Across Diverse Human Populations., William Gibson

Electronic Theses and Dissertations

The adaptive immune system relies on a diverse set of over one hundred immunoglobulin (IG) genes across three genomic loci that are variably combined to form antibodies (Ab). The IG Lambda locus is one of two loci which encodes the IG light chain. The complexity of the IGL locus severely limits the effective use of standard short-read sequencing, limiting our knowledge of population diversity in these loci. We leveraged single molecule real-time (SMRT) long-read sequencing in conjunction with IGL-targeted DNA capture to develop the method IG-Cap for accurate and high-throughput sequencing of the IGL locus. We benchmarked this method using …


Connectivity Of Amygdala Somatostatin-Expressing Neurons And Their Role In Taste-Guided Behavior., Jane Jeruto Bartonjo Aug 2023

Connectivity Of Amygdala Somatostatin-Expressing Neurons And Their Role In Taste-Guided Behavior., Jane Jeruto Bartonjo

Electronic Theses and Dissertations

The nucleus of solitary tract (NST) and parabrachial nucleus (PBN) represent the first and second central synapses of ascending gustatory information. Neural processing in these nuclei is influenced by descending input from forebrain regions such as the central nucleus of the amygdala (CeA). In mice, we have shown that somatostatin (Sst) expressing neurons of CeA that project to NST and PBN are largely distinct cell populations and optogenetic inhibition of the CeA/Sst-to-NST subpopulation increases the intake of high concentrations of quinine with no apparent effect on sucrose intake. Synaptic connectivity of these cells is needed to understand the possible mechanisms …


Transmission And The Evolution Of Diseases Caused By Chlamydia Trachomatis, Sars-Cov-2, And Plasmodium Species., Nathan Steffens May 2023

Transmission And The Evolution Of Diseases Caused By Chlamydia Trachomatis, Sars-Cov-2, And Plasmodium Species., Nathan Steffens

Electronic Theses and Dissertations

Principles of natural selection have proven valuable for explaining why pathogens cause the diseases that they do. In theory, the evolved level of host exploitation should reflect how dependent a pathogen is on host health for transmission. This dependency is shaped by transmission mode and transmission opportunity, which should therefore be predictors of disease manifestations. In this dissertation, I apply these principles to investigations of depression in Chlamydia trachomatis and virulence of SARS-COV-2 and Plasmodium species. This dissertation has five chapters. In chapter I, I describe the theoretical foundation of my dissertation research. I also briefly introduce each study system. …


Identification Of A Role Beyond Iron Acquisition For Yersiniabactin During Yersinia Pestis Infection., Sarah Price May 2023

Identification Of A Role Beyond Iron Acquisition For Yersiniabactin During Yersinia Pestis Infection., Sarah Price

Electronic Theses and Dissertations

Yersinia pestis is a Gram-negative re-emerging bacterial pathogen that is responsible for bubonic, septicemic, and pneumonic plague. Y. pestis and other bacteria require transition metals, such as iron, zinc, and manganese, to maintain intermediary metabolism, transcriptional regulation, and virulence. To inhibit infection, eukaryotic organisms have developed distinct mechanisms, called nutritional immunity, to sequester these important nutrients from invading bacteria. For pathogens to colonize the vertebrate host, they have evolved dedicated acquisition systems for transition metals. During infection, Y. pestis overcomes iron limitation by secreting the siderophore yersiniabactin. Additionally, Y. pestis requires zinc for infection and utilizes high affinity transporters to …


Synaptic Properties Of Parabigeminal Circuits., Kyle Whyland May 2023

Synaptic Properties Of Parabigeminal Circuits., Kyle Whyland

Electronic Theses and Dissertations

Subcortical structures of the visual system have been the subject of intense study in recent years, but there remain some important unanswered questions regarding the synaptic relationships linking the nuclei that comprise this important sensory network within the brain. In these studies, we use several modern and traditional approaches, including viral tract tracing, in vitro slice physiology, immunohistochemistry, optogenetics, and electron microscopy to characterize the circuits linking the superior colliculus (SC), parabigeminal nucleus (PBG), and lateral geniculate nucleus (LGN), with particular focus on GABAergic and cholinergic cell types. We found that the SC, an important visuomotor structure with connections to …