Medicine and Health Sciences Commons^™

Virulence Regulation In Pseudomonas Aeruginosa Via The Alginate Regulators, Algu And Algr, The Posttranscriptional Regulator, Rsma, And The Two-Component System, Algz/R, Sean Stacey

Electronic Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative bacillus able to colonize a wide variety of environments. In the human host, P. aeruginosa can establish an acute infection or persist and create a chronic infection. P. aeruginosa is able to establish a niche and persist in human hosts by using a wide array of virulence factors used for: movement, killing host cells, and evading immune cells and antibiotics. Understanding virulence factors and their regulation has proved to be an important means of combating the morbidity and mortality of P. aeruginosa as well as the ever-increasing threat of drug resistance. By targeting virulence factors …

The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni

Electronic Theses and Dissertations

Excessive alcohol consumption is the primary contributing factor in the development of alcoholic liver diseases (ALD). Nicotine contained in tobacco is a major addictive alkaloid, which enhances the effects of ALDs. The major enzyme involved in nicotine metabolism is cytochrome P450 2A5 (CYP2A5) which is produced in the liver. Alcohol can stimulate the CYP2A5 enzyme. We utilized cyp2a5-/- knockout mice in this research to examine the effects of CYP2A5.

The cyp2a5-/- mice and wild-type (WT) mice were fed liquid ethanol diet with or without nicotine to induce ALD. Nicotine enhancing effects on ALD were observed in WT mice but not …

The Role Of Non-Neuronal Acetylcholine In Urogenital Chlamydial Infection, Jessica R. Lockhart

Electronic Theses and Dissertations

Chlamydia trachomatiscauses a bacterial sexually transmitted infection, Chlamydia, that is often chronic and casues reproductive complications in women. We hypothesized that Chlamydia infection increases local acetylcholine (ACh) production, which regulates the host’s inflammatory response to the infection. Female mice infected with C. muridarumwere sacrificed at days 3, 9, 15, and 21 post-infection, genital tract tissues harvested, and immunohistochemistry performed to enumerate ACh-producing cells. Infection increased the number of ACh-producing cells in cervical tissue at days 3,15, and 21 post-infection (pi), uterine tissue at day 3 and 9 pi, and ovarian tissue day 3, 15, and 21 pi. These …

Cholesterol Metabolism And Statin Effects On An Fh Class Ii Ldl-Receptor Mutation., Linda Omer

Electronic Theses and Dissertations

Familial hypercholesterolemia (FH) is a common genetic disease and has been studied with the aim of finding a curative measure for decades. FH is caused by mutations in the low-density lipoprotein receptor (LDLR) resulting in defects in LDL-cholesterol (LDL-C)-receptor mediated endocytosis and development of premature cardiovascular disease (CVD). Here I describe the use of a corrected and non-corrected LDLR FH cell model to investigate receptor-mediated endocytosis and statin effects. For these studies, we reprogrammed FH fibroblast cells to induced pluripotent stem cells (iPSC) and confirmed their pluripotency and ability to differentiate to hepatocyte-like cells (HLC). A clustered regularly interspaced short …

Adolescent Sexual And Reproductive Health In The Gambia., Sandhya Lohani

Electronic Theses and Dissertations

Adolescence is a crucial period in human development. Knowledge and awareness about when to have children, when to have sex, and use of contraceptives impacts the chances of teenage pregnancy and risk of sexually transmitted diseases. The objective of this study is to determine the prevalence and associated risk factors related to age of sexual debut, teenage pregnancy, and use of contraceptives in the Gambia. This study also compares the data with 2014 survey research conducted in the Gambia. The total study population were 50 adolescents aged 13-21 years from Bafuluto and surrounding communities in the Gambia. Among 50 respondents, …

The Migration And Developmental Remodeling Of Intrinsic Interneurons In Visual Thalamus And The Role Of Retinal Signaling., Naomi E. Charalambakis

Electronic Theses and Dissertations

The dorsal lateral geniculate nucleus (dLGN) of the mouse is a model system to study the development of thalamic circuitry. While most studies focus on relay neurons of dLGN, little is known about the factors regulating the development of the other principal cell type, intrinsic interneurons. To date, the targeting and migratory path of dLGN interneurons as well as their morphological development remains unclear. Here we examined whether the migration, structure, and function of interneurons relies on retinal signaling. We took a loss-of-function approach and crossed GAD67-GFP mice, which express green fluorescent protein (GFP) in dLGN interneurons, with math5 nulls …

Assessing The Role Of Arsenite In Disrupting The Egfr Signaling Axis., Christine Kim

Electronic Theses and Dissertations

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase localized on the cell surface. Overexpression of EGFR has been used as biomarkers for many different types of cancers, including lung cancer. There is a strong association between arsenic and lung cancer development, although the mechanism is unclear. We hypothesize that chronic exposure of “a physiologically relevant” level of arsenite disrupts the EGFR endocytic trafficking. The goal of this project is to identify molecular mechanisms and roles of chronic arsenite-induced EGFR overexpression in lung cancer development. A non-malignant human bronchial epithelial cell line, Beas-2B cells were exposed to 100 …

Epidermal Growth Factor Receptor (Egfr) Inhibition By Polychlorinated Biphenyls Contributes To Non-Alcoholic Fatty Liver Disease (Nafld)., Josiah Hardesty

Electronic Theses and Dissertations

This dissertation describes how poly-chlorinated biphenyls (PCBs) exacerbate the pathogenesis of non-alcoholic fatty liver disease (NAFLD). While PCBs were banned in 1979, they still persist in contaminated biota, including food, and are detected in human plasma and adipose. The body burden of PCBs is associated with elevation of liver enzymes and necrosis markers in humans, characteristic of NAFLD. PCB exposure in high-fat diet fed mice leads to steatohepatitis that recapitulate the findings seen in exposed humans. The global estimate of people diagnosed with NAFLD is up to 1 in 4 people, unrelated to dietary or genetic factors. The hepatic mechanisms …

The Effect Of Wild Blueberry Bioactives On Endothelial Cell Migration And Angiogenesis: An In Vitro Mechanistic, Genomic And Proteomic Approach, Panagiotis Tsakiroglou

Electronic Theses and Dissertations

The goal of this study is to investigate the effects of wild blueberry fractions (Anthocyanins and Phenolic acids) on vascular function and physiology. More specifically the potential effects of the above fractions and their combination in physiological concentrations on endothelial cell migration, angiogenesis, gene expression and proteins synthesis of markers related to the above processes. The objectives are to study whether anthocyanins, phenolic acids and their combinations (ACNs:PAs) affect: a) cell proliferation, b) speed of endothelial cell migration, c) angiogenesis, d) gene expression of genes critical for cell migration and angiogenesis such as RAC1, RHOA, AKT1, eNOS and VEGF and …

Genetic Modification Of Inherited Retinopathy In Mice, Yang Kong

Electronic Theses and Dissertations

The retina, as a critical component of the sensory system, consists of multiple cell types, of which, photoreceptors play a key role in receiving, integrating and transmitting light signals. The biofunctions of photoreceptors rely on their proper growth and development, which is predominantly governed by a cluster of molecules that comprise the transcriptional regulation for photoreceptor development. Any disruption of these molecules potentially incurs retinal pathologies.

It is known that deficiencies of nuclear receptor subfamily 2 group E member 3 (NR2E3) or neural retina leucine-zipper (NRL), two molecules in regulating photoreceptor cell development, cause photoreceptor dysplasia. In a sensitized chemical …

3d-Printed Fluidic Devices And Incorporated Graphite Electrodes For Electrochemical Immunoassay Of Biomarker Proteins, Abdulhameed Alabdulwaheed

Electronic Theses and Dissertations

Biomarkers are measurable indicators of health status or disease state that can be used for diagnosis and may help guide patient treatment strategies. Enzyme-linked immunosorbent assays (ELISA) and other many clinical techniques currently used for measuring biomarker proteins lack sensitivity, demand high analysis cost, are often not well-suited for measuring multiple biomarkers in a single sample, and require long analysis times. Here, we demonstrate simple, low-cost 3D-printed flow-through devices with integrated electrodes modified with gold nanoparticles (AuNPs) for electrochemical immunoassays of S100B, a biomarker protein related to conditions like skin cancer and brain injuries. Flow-through devices are fabricated from photocurable-resin …

Combination Oral Immunotherapy With Il-10 And Il-12 Effectively Treats Colon Tumors Via Synergistic Effects On Il-17 Producing T Cells And Colon Epithelial Barrier Integrity., Neal Bhutiani

Electronic Theses and Dissertations

In this dissertation, the relationship between colon cancer and inflammation, the utility of novel imaging modalities for diagnosis of colitis and cancer, and the therapeutic efficacy of orally delivered, particle-based immunotherapy for the treatment of colon cancer are evaluated. In Chapters One and Two, multispectral optoacoustic tomography (MSOT) is demonstrated to effectively detect colon inflammation without the use of exogenous contrast prior to detection using conventional colonoscopy. Oral particle uptake is demonstrated in the distal small intestine and proximal colon, confirming site-specific delivery. In Chapter Three, administration of IL-10 and IL-12 containing particles is shown to act synergistically to significantly …

Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor

Electronic Theses and Dissertations

Metabolomics, the study of small molecules in biological systems, has enjoyed great success in enabling researchers to examine disease-associated metabolic dysregulation and has been utilized for the discovery biomarkers of disease and phenotypic states. In spite of recent technological advances in the analytical platforms utilized in metabolomics and the proliferation of tools for the analysis of metabolomics data, significant challenges in metabolomics data analyses remain. In this dissertation, we present three of these challenges and Bayesian methodological solutions for each. In the first part we develop a new methodology to serve a basis for making higher order inferences in metabolomics, …

Deciphering The Role Of Human Arylamine N-Acetyltransferase 1 (Nat1) In Breast Cancer Cell Metabolism Using A Systems Biology Approach., Samantha Marie Carlisle

Electronic Theses and Dissertations

Background: Human arylamine N-acetyltransferase 1 (NAT1) is a phase II xenobiotic metabolizing enzyme found in almost all tissues. NAT1 can additionally hydrolyze acetyl-coenzyme A (acetyl-CoA) in the absence of an arylamine substrate. NAT1 expression varies inter-individually and is elevated in several cancers including estrogen receptor positive (ER+) breast cancers. Additionally, multiple studies have shown the knockdown of NAT1, by both small molecule inhibition and siRNA methods, in breast cancer cells leads to decreased invasive ability and proliferation and decreased anchorage-independent colony formation. However, the exact mechanism by which NAT1 expression affects cancer risk and progression remains unclear. Additionally, consequences …

Alpha-Amino Methylation And Acetylation Are Novel Regulators Of Myl9 Function., Christopher David Nevitt

Electronic Theses and Dissertations

Dysregulation of alpha-amino post-translational modifications (Nα-PTMs) is found in multiple cancers and developmental disorders. However, the exact roles Nα-PTMs play in regulating protein function remain poorly understood. I sought to clarify the role of Nα-methylation and Nα-acetylation in the regulation of Myosin Regulatory Light Chain 9 (MYL9). MYL9 is a key cytoskeletal regulator and transcription factor and is the first protein confirmed to undergo both Nα-methylation and Nα-acetylation. Through this work I revealed novel regulatory features of MYL9, while also presenting a framework by which to understand the coordinated regulation of proteins by Nα-methylation and Nα-acetylation. Nα-PTM selective mutants of …

A Clinically Relevant Mouse Model Of Cisplatin-Induced Kidney Injury., Cierra Nichole Sharp

Electronic Theses and Dissertations

Cisplatin is a potent chemotherapeutic used for the treatment of many solid cancers, including testicular, ovarian, and lung cancer. Cisplatin causes many adverse side effects, of which nephrotoxicity leading to acute kidney injury is dose-limiting. Approximately 30% of patients will develop nephrotoxicity with cisplatin, and will either have their next dose of cisplatin lowered, skipped, or be switched to a less nephrotoxic chemotherapeutic altogether. These outcomes are not ideal when trying to treat cancer. Previously, it was believed that patients could recover from cisplatin-induced acute kidney injury with little to no lasting effects, but recent longitudinal studies have shown this …

Characterizing The Role Of Fungal Shape In A Zebrafish Model Of Invasive Candidiasis, Brittany Seman

Electronic Theses and Dissertations

Candida albicans is a common hospital-acquired fungal infection, and disseminated disease claims up to one-half of those afflicted. C. albicans has a unique ability to differentiate its shape during infection, and this differentiation is thought to be a major virulence factor during invasive infections. Each shape is proposed to have a specialized role: filaments drive tissue invasion and yeast mediate dissemination to the bloodstream. However, it has been difficult to test these hypotheses for two reasons. First, rigorous testing of shape-specific roles requires diverse strategies of shape modulation that restrict the possibility of manipulation-specific artifacts. Second, although connecting shape to …

Melatonin-Micronutrients Osteopenia Treatment Study (Mots): A Translational Study Assessing The Effects Of Melatonin, Strontium Citrate, Vitamin D3 And Vitamin K2 On Bone Density, Bone Turnover Markers And Health-Related Quality Of Life In Postmenopausal Osteopenic Women Following A One-Year Double-Blind Randomized Placebo-Controlled Trial And On Osteoblast-Osteoclast Co-Cultures, Sifat Maria

Electronic Theses and Dissertations

Objective: The purpose of this study was to assess if a novel combination of melatonin and three other natural bone-aiding micronutrients: strontium citrate, vitamins D₃ and K₂ (MSDK) could improve bone health by modulating the activity of osteoblasts and osteoclasts in favor of balanced bone remodeling and by improving the overall health-related quality of life in postmenopausal osteopenic women.

Methods: The Melatonin-micronutrients Osteopenia Treatment Study (MOTS) is a translational research study that used both clinical and in vitro approaches to assess the efficacy of MSDK on bone health in women and to identify potential mechanisms for its effects. …

Tissue Engineered Micro And Macrovasculature Utilizing Stromal Vascular Fraction., Joseph Samir Zakhari

Electronic Theses and Dissertations

This dissertation describes the use of stromal vascular fraction to tissue engineer 3D microvasculature and macrovasculature. Stromal vascular fraction is an easily isolatable cell source from adipose tissue depots. It has demonstrated remarkable potential both in vitro and in vivo for forming microcirculation capable of perfusion upon implantation. SVF is clinically utilized as a therapeutic cell source for anti-inflammation for osteoarthritis and is being studied for ischemic tissue application to stimulate revascularization. The work described herein is divided within four chapters. Chapter I provides an introductory overview and lists the aims and hypothesis for the dissertation. Chapter II describes experiments …

Therapeutic Potential Of A Plant-Made Cholera Toxin B Subunit Variant For The Treatment Of Ulcerative Colitis., Joshua Mark Royal

Electronic Theses and Dissertations

Cholera toxin B subunit (CTB) is a mucosal immunomodulatory protein that induces robust mucosal and systemic antibody responses. This well-known biological activity has been exploited in cholera prevention (as a component of Dukoral® vaccine) and vaccine development for decades. On the other hand, several studies have investigated CTB’s immunotherapeutic potential in the treatment of inflammatory diseases such as Crohn’s disease and asthma. Furthermore, we recently found that a plant-made variant of CTB (CTBp) could induce colon epithelial wound healing in mouse colitis models. In this thesis, it is revealed that the wound healing effects are unique to the plant-made variant, …

Inflammasome Independent Leukotriene-B4 Production Drives Crystalline Silica Induced Sterile Inflammation., Bindu Hegde

Electronic Theses and Dissertations

Silicosis is an irreversible lung inflammatory disease caused by chronic exposure to crystalline silica (CS) and is one of the most prevalent occupational diseases worldwide. Lipid chemoattractant Leukotriene B₄ (LTB₄) plays an important role in neutrophilic inflammation that drives silicosis and promotes lung cancer. Previous studies in our laboratory have demonstrated that CS-induced neutrophilic inflammation and lung tumor burden in K-ras^LA1 mice is abrogated in the LTB₄-receptor deficient mice. Another pathway whose importance is well studied in the progression of silicosis is the Nalp3 inflammasome pathway. Studies have shown inflammasome- dependent IL-1b to be …

Nutritional Virulence Of Legionella Pneumophila., Ashley M. Best

Electronic Theses and Dissertations

Legionella pneumophila is an environment organism that parasitizes a wide range of protozoa. Growth within the environmental host primes L. pneumophila for infection of human alveolar macrophages when contaminated aerosols are inhaled. Intracellular replication within either host requires the establishment a replicative niche, known as the Legionella-containing vacuole (LCV). Biogenesis of the LCV depends on the type IVb translocation system, the Dot/Icm, to translocation >320 effectors into the host cytosol. Effectors are responsible for preventing lysosome fusion to the LCV, recruitment of ER-derived vesicles to the LCV, and modulation of a plethora of host processes to promote the intracellular …

Loss Of The Na+/H+ Exchange Regulatory Factor 1 Results In Increased Susceptibility To Cisplatin-Induced Acute Kidney Injury., Adrienne M. Bushau-Sprinkle

Electronic Theses and Dissertations

Background. Acute kidney injury (AKI), an abrupt loss of kidney function which carries a high mortality and confers an increased risk of chronic kidney disease, develops in 30% of patients who receive cisplatin, a widely used chemotherapeutic agent [1], [2], [3]. The sodium hydrogen exchange regulatory factor isoform 1 (NHERF1) is a scaffolding protein that anchors multiple membrane proteins, in renal proximal tubules [4]. NHERF-1 deficient mice have aberrant localization of BBM proteins in intracellular compartments [5]. The investigators have recently demonstrated NHERF1 deficient proximal tubule cells have an underlying …

Exacerbation Of Δefp Sickness In Escherichia Coli By An Uncharacterized Rna Helicase, Robert Wingo

Electronic Theses and Dissertations

In Escherichia coli, growth is rate-limited by translation capacity [1]. Stalled ribosomes have profound effects on a cell such as altered mRNA abundance, decreased ribosome availability, and an imbalanced proteome. The absence of elongation factor P (EF-P), a universally conserved transpeptidation enhancer, presents an extreme example of this scenario, wherein ribosomes accumulate disproportionately onto messages that are more slowly translated and cell growth becomes notably impaired. We discovered that faster-growing cells arise spontaneously in Δefp cultures, suggesting that translation defects could be circumvented by mutating other genes. This thesis presents a genetic and biochemical analysis of a mechanism Δefp cells …

Embryonic Stem Cell Derived Exosomes Enhance Cardiac Stem Cell Differentiation Into Heart Cells, Jamillah Hammond

Electronic Theses and Dissertations

Transplantation of embryonic stem (ES) cells into the ischemic and infarcted heart has proven to repopulate cardiac cell populations, attenuate structural cardiac remodeling, and rescue cardiac function. Unfortunately, the pluripotency of ES cells increases risk of teratoma formation in vivo. Exosomes, smaller in comparison to ES cells, are cell free carriers of miRNA, proteins, and lipids, and do not suggest risk of teratoma formation. Exosomes have been proposed to mediate and attenuate regeneration following myocardial infarction (MI), however, the role of exosomes derived from ES cells (ES-Exo) in activating resident cardiac stem cells (CSCs) to undergo cardiac differentiation is not …

Neuromuscular Junction Defects In A Mouse Model Of Charcot-Marie-Tooth Disease Type 2o, Thywill Sabblah

Electronic Theses and Dissertations

Charcot Marie Tooth disease (CMT) represents the most common inheritable peripheral group of motor and sensory disorders; affecting 1 in 2500 people worldwide. Individuals with CMT experience slow progressing weakness of the muscle, atrophy, mild loss of motor coordination and in some cases loss of sensory function in the hands and feet which could ultimately affect mobility. Dynein is an essential molecular motor that functions to transport cargos in all cells. A point mutation in the dynein heavy chain was discovered to cause CMT disease in humans, specifically CMT type 2O. We generated a knock-in mouse model bearing the same …

Role Of Mycobacterium Avium Paratuberculosis (Map) And Tnfsf15 Snps On Tl1a In Cd, Sayf Al-Deen Hassouneh

Electronic Theses and Dissertations

Tumor Necrosis Factor-Like Ligand 1a (TL1A) is a cytokine encoded by Tumor Necrosis Factor Super Family 15 gene (TNFSF15) gene mostly in endothelial cells which binds to T-cells and foments the production of pro-inflammatory cytokines including TNF-α, IL-6, IL-1b, IFN- γ and IL-13. TL1A level is elevated in inflammatory diseases including Crohn's Disease (CD). Although Single Nucleotide Polymorphisms (SNPs) in TNFSF15 have been reported in CD, no studies have investigated the effect of these SNPs on TL1A, inflammation, and susceptibility to Mycobacterium avium subspecies paratuberculosis (MAP) infection. MAP is a strong candidate in CD pathogenesis. This study is designed to …

Development Of Low Frequency Electron Paramagnetic Resonance Methods And Instrumentation For Biological Applications, Laura A. Buchanan

Electronic Theses and Dissertations

EPR is a powerful biophysical tool that can be used to measure tumor physiology. With the addition of magnetic field gradients, the spectral properties of paramagnetic species can be mapped. To facilitate EPR imaging, methods and instrumentation at frequencies between 250 MHz and 1 GHz were developed.

At low spin concentrations, the rapid scan background signal is often many times larger than the EPR signal of interest. To help remove the background contribution, a data acquisition procedure that takes advantage of a cross-loop resonator and bipolar power supplies was developed at 250 MHz. In this procedure, two scans are collected. …

Development Of A Non-Human Primate Model For Staphylococcus Aureus Nasal Carriage, Amanda Lasseter

Electronic Theses and Dissertations

Staphylococcus aureus nasal carriage (SANC) is largely asymptomatic, but presents a risk of autoinfection and dissemination to new immunocompromised hosts. SA disease states range from mild cutaneous infections to life-threatening bacteremia. Historically utilized rodent models do not naturally carry SA in the nose, are insufficient in longitudinal SANC experimentation, and lack immune factors that are vital in human clearance of SA. The nasal passages of non-human primates are similar anatomically and histologically, and reproductive mucosal studies have shown similar immune responses to pathogens and human-relevant microbial profiles. Seventeen captive pigtailed macaques (Macaca nemestrina) were found to naturally carry SA in …

A Scale Space Local Binary Pattern (Sslbp) – Based Feature Extraction Framework To Detect Bones From Knee Mri Scans, Jinyeong Mun

Electronic Theses and Dissertations

The medical industry is currently working on a fully autonomous surgical system, which is considered a novel modality to go beyond technical limitations of conventional surgery. In order to apply an autonomous surgical system to knees, one of the primarily responsible areas for supporting the total weight of human body, accurate segmentation of bones from knee Magnetic Resonance Imaging (MRI) scans plays a crucial role. In this paper, we propose employing the Scale Space Local Binary Pattern (SSLBP) feature extraction, a variant of local binary pattern extractions, for detecting bones from knee images. The proposed methods consist of two phases. …