Medicine and Health Sciences Commons^™

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 …

Incidence And Determinants Of Hypertensive Disorders Of Pregnancy In The Us: Hospitalization Discharge Rate For Preeclampsia, Eclampsia, And Gestational Hypertensions, 2016-2018., Kahir S. Jawad

Electronic Theses and Dissertations

Background: Hypertension remains one of the most prevalent medical issues in pregnancy. It contributes considerably to maternal and fetal morbidity and mortality, making it one of the most significant public health problems. Although various epidemiological studies have been conducted over the past decades to assess the disease incidence and key risk factors associated with hypertensive disorders of pregnancy, current incidence rates and trends are lacking. This is a novel and significant study because there are no current population-based incidence estimates of hypertensive disorders of pregnancy and their subtypes and very few studies with the power to explore a wide range …

Metabolic Foundations Of Exercise-Induced Cardiac Growth., Kyle Fulghum

Electronic Theses and Dissertations

Regular aerobic exercise promotes physiological cardiac growth, which is an adaptive response thought to enable the heart to meet higher physical demands. Cardiac growth involves coordination of catabolic and anabolic activities to support ATP generation, macromolecule biosynthesis, and myocyte hypertrophy. Although previous studies suggest that exercise-induced reductions in cardiac glycolysis are critical for physiological myocyte hypertrophy, it remains unclear how exercise influences the many interlinked pathways of metabolism that support adaptive remodeling of the heart. In this thesis project, we tested the general hypothesis that aerobic exercise promotes physiological cardiac growth by coordinating myocardial metabolism to promote glucose-supported anabolic pathway …

The Experience Of Scanxiety In Survivors Of Pancreatic Cancer: A Phenomenological Study., Susan Winebrenner

Electronic Theses and Dissertations

Surveillance scans can signify a crisis point in a cancer patient’s life, provoking fear and anxiety that negatively impact quality of life. Scan-related anxiety or scanxiety has been briefly discussed in the literature among lung cancer and lymphoma populations, but relatively few investigations have studied the psychological impact of routine surveillance scans during cancer survivorship. The purpose of this study was to illuminate the lived experience of scanxiety in survivors of pancreatic cancer who have undergone curative surgical resection. Hermeneutic phenomenology as applied by Heidegger provided the philosophical underpinnings for this study and van Manen’s methodological approach was used to …

The Role Of Obesity In Macrophage-Mediated Mechanisms Promoting Early-Onset Colon Cancer., Katharina Marietta Scheurlen

Electronic Theses and Dissertations

Early-onset colon cancer (EOCC) is a leading cause of cancer death among people younger than 50 years of age in the United States and is associated with metabolic dysfunction and obesity. Anti-inflammatory tumor-associated macrophages (TAM) and low Peroxisome Proliferator Activated Receptor Gamma (PPARγ) gene expression in colon cancer (CC) tissue promote tumor progression and decreased patient survival. Obesity-related hormones, such as leptin and adiponectin, have the potential to affect gene expression in TAM to promote CC progression and thereby link obesity and EOCC. The aim of this project was to identify target genes in human CC and to investigate the …

The Impact Of Volume Of Tissue Activation On Cortical-Striatal Networks And Verbal Fluency Declines In Post-Deep Brain Stimulation Parkinson's Disease Patients., Alexander Luke Alley

Electronic Theses and Dissertations

This study investigated the cortical-striatal networks of verbal fluency declines in 6-month, post-operative, deep brain stimulation Parkinson’s Disease patients. Nine Parkinson’s disease participants with implanted STN or GPi DBS systems were recruited for this study. Verbal fluency data was obtained from each patient preoperatively and 6- months post implantation. The stimulation-based volume of tissue activated area (VTA) of each target site (STN or GPi) was analyzed using Lead-DBS and Lead-Group. The white matter tracks intersecting each patient’s VTA, terminating in the pre-SMA, SMA, caudate nucleus, and anterior cingulate were investigated and correlated with verbal fluency declines. We found statistically significant …

Role Of Meibum And Tear Phospholipids In The Evaporative Water Loss Associated With Dry Eye., Samiyyah M. Sledge

Electronic Theses and Dissertations

It is generally believed that the tear film lipid surface film inhibits the rate of evaporation (Revap) of the underlying tear aqueous. It is also generally believed that changes in the composition of the tear film lipid layer is responsible for an increase in Revap in patients with dry eye. Both of these ideas have never been proven. The purpose of the current studies was to test these ideas. Revap was measured in vitro gravimetrically. Lipid spreading was measured using Raman spectroscopy and microscopy. The influence of the following surface films on the Revap of the sub phase of physiologically …

Harnessing The Power Of Trained Immunity In The Setting Of Pancreatic Cancer: A Novel Mechanism Of Immune Trafficking And Tumor Control., Anne Elena Geller

Electronic Theses and Dissertations

Despite the success of immunotherapy in many types of cancer, pancreatic adenocarcinoma (PDAC) has yet to benefit. Innate immune cells are critical to antitumor immunosurveillance and recent studies have revealed that these populations possess a form of memory, termed trained innate immunity, which occurs through transcriptomic, epigenetic, and metabolic reprograming. Though trained innate immunity has mostly been investigated in the context of infection, the induction of trained innate immunity could also protect against tumors, and specifically pancreatic tumors. Here, we demonstrate that yeast-derived particulate β-glucan, a known inducer of trained immunity, traffics to the pancreas following IP administration. This causes …

Identifying The Cardiovascular Effects Of Multiple Pollutants., Katlyn Elizabeth Mcgraw

Electronic Theses and Dissertations

Cardiovascular disease (CVD) is the leading cause of death from environmental exposures. Although exposure to PM_2.5 is an established risk factor for CVD, the contribution of other hazardous pollutant exposure to CVD is less clear. Overall, this work aimed to examine the effect of pollutants with lesser documented effects on cardiovascular disease using a multi-pronged approach to exposure assessment. The three aims were to examine the relationship between county-level toxic chemical releases and CVD mortality in the contiguous United States between 2002 and 2012, to assess the relationship between individual-level VOC metabolites and vascular function, and to build multipollutant …

Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding

Electronic Theses and Dissertations

Despite efforts to decrease the global health burden of malaria, infections with Plasmodium species continue to cause over 200 million episodes of malaria each year which resulted in 405,000 deaths in 2018 [1]. One complication of malaria is increased susceptibility to invasive bacterial infections. Plasmodium infections impair host immunity to non-Typhoid Salmonella (NTS) through activities of heme oxygenase I (HO-I) )-induced release of immature granulocytes and myeloid cell-derived IL-10. Yet, it is not known if these mechanisms are specific to NTS. We show here, that Plasmodium yoelii 17XNL (Py) infected mice had impaired clearance of systemic Listeria monocytogenes (Lm) during …

The Role Of Slc7a11 In Controlling Extracellular And Intracellular Redox Environments Of Lung Fibroblasts - Potential Targets For Intervention In Aging And Idiopathic Pulmonary Fibrosis., Yuxuan Zheng

Electronic Theses and Dissertations

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease characterized by extracellular matrix deposition by fibroblasts. Aging and oxidative stress increase the susceptibility to IPF. Redox couples, cysteine/cystine (Cys/CySS) and glutathione/glutathione disulfide (GSH/GSSG), and their redox potentials (E_h) quantify oxidative stress. Fibroblasts from old mice maintain more oxidized extracellular E_h(Cys/CySS) than young mice. Microarray shows down-regulation of Slc7a11 potentially mediates this age-related oxidation. Slc7a11 is the key component of system X_c^-, an antiporter that imports CySS and exports glutamate. The first aim of this dissertation is to investigate the mechanistic link between Slc7a11 …

The Identification Of Long Non-Coding Rna Zfas1 Through An Exploratory Rna-Sequencing Analysis And Its Association With Epithelial-To-Mesenchymal Transition In Colon Cancer Adenocarcinoma., Stephen J. O'Brien

Electronic Theses and Dissertations

Colorectal adenocarcinoma is the fourth most common cancer diagnosed worldwide and is a significant cause of morbidity and mortality. This dissertation performed an exploratory RNA-sequencing analysis comparing gene expression between colon adenocarcinoma tissue and paired normal colon epithelium. After identification of a number of lncRNAs that were increased in expression in colon adenocarcinoma compared to normal colon epithelium, we aimed to validate the expression and investigate their function in vitro. Specifically, we focused on the lncRNA ZFAS1 and its association with epithelial-to-mesenchymal transition. These studies found the following: 1. Seven candidate lncRNAs were identified from the exploratory RNA-sequencing analysis to …

The Effects Of Nicotine And Cigarette Smoking On Cardiac Electrophysiology., Affan B. Irfan

Electronic Theses and Dissertations

Cigarette smoking is a leading cause of preventable disease and premature death worldwide. The adverse effects of cigarette smoking, including proarrhythmia, are related to the mixture of chemicals, including nicotine (which sustains tobacco addiction). However, it remains unclear which individual tobacco smoke constituents and biological pathways mediate this increased risk. The purpose of this research was to explore the chronic effects of cigarette smoking, as well as compare the acute effects of nicotine and cigarette smoking, and the possible role of β-adrenoreceptors, on human cardiac electrophysiology. Chapter 1 is a comprehensive literature review of (a) the ex vivo and in …

Characterizing The Role Of Extracellular Matrix In Non-Small Cell Lung Carcinoma Metastasis Using A 3d Microenvironment Mimetic In-Vitro Culture System., Douglas John Owulaku Saforo

Electronic Theses and Dissertations

Lung cancer is the leading cause of cancer related death in the United States and worldwide. Five-year survival rates for non-small cell lung carcinoma patients have not improved in decades, and a majority of patients succumb to metastasis. Identification of therapeutic targets for metastatic disease is essential for the development of novel therapies. However, current 2-dimensional (2D) in vitro models are not reflective of the tumor microenvironment (TME) and are inadequate in identifying therapeutic targets. We adapted a 3-dimensional (3D) extracellular matrix (ECM) in vitro model to a hypoxic incubator to approximate physiological hypoxia of the TME in a microenvironment …

Comparative Spending Of Medicaid Dollars On Child Participants Of Kentucky’S Sobriety Treatment And Recovery Teams Program Versus A Matched Comparison Group., Matthew Thomas Walton

Electronic Theses and Dissertations

Child protective services agencies have long observed the complicating role that parental substance use and addiction plays in cases of child maltreatment. Families who struggle with these problems present unique challenges for child welfare professionals. These families are typically more difficult to engage, more likely to have children removed from the home, and have poorer outcomes when compared to other families. These poorer outcomes often include health problems. Addiction has well-known effects on health, and the specific manifestations of these problems for parents have been documented for years in child protection casework. However, what has been less investigated are the …

Novel Mechanisms And Biomarkers In Alcohol-Induced Organ Injury., Christine E. Dolin

Electronic Theses and Dissertations

Background. Ethanol (EtOH) consumption is known to affect multiple organs; this is unsurprising, as the concentration of EtOH in the blood at relevant doses reaches the millimolar range. The overarching goal of this dissertation was to elucidate mechanisms of alcohol-induced organ injury, specifically the effects of alcohol on the hepatic extracellular matrix (ECM) proteome, the alcoholic hepatitis (AH) plasma peptidome, and the effects of alcohol on the renal cortex proteome and transcriptome. Methods. Mice were pair-fed ethanol-containing liquid diet chronically, and then some mice were administered lipopolysaccharide (LPS). Liver sections from these mice were processed in a series of increasingly …

An Evaluation Of The Supply And Demand Of Radiation Oncology Medical Physicists In The United States., Christine Marie Swanson

Electronic Theses and Dissertations

Background: This dissertation is a mixed methods evaluation of the radiation oncology medical physics workforce in the United States. Radiation oncology medical physicists serve a vital role in the safe treatment of patients with radiation therapy. While cancer incidence continues to rise, the pathways to board certification in radiation oncology medical physics continue to narrow causing a potential shortage of radiation oncology physicists in the United States. While there is no lack of data about the medical physics community it has scarcely been used to evaluate the current state of the workforce. In order to ensure patient safety, appropriate physics …

Characterizing The Gut Microbiota During Plasmodium Infection And Antimalarial Treatment., Joshua E. Denny

Electronic Theses and Dissertations

Plasmodium, the parasitic cause of malaria, is a global pathogen, annually causing 216 million infections and 445,000 deaths. As drug resistance continues develop and no effective vaccine is available, it is critical to understand the factors underlying the severity of this disease. Plasmodium is an extra-gastrointestinal tract infection where the parasite infects red blood cells causing clinical malaria. However, recent publications have pointed to interactions between the gut microbiota and malaria. With this in mind, the role of the gut microbiota in malaria infection was studied. C57BL/6 mice from different vendors displayed differential resistance and susceptibility to severe malaria, …

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, …

Wnt/Β-Catenin Mediated Cancer Stem Cell Activation In Hepatocellular Carcinoma., Harshulkumar M. Pandit

Electronic Theses and Dissertations

Hepatocellular carcinoma (HCC) is one of the deadliest cancers, with variable presentation, high chemotherapy resistance and early tumor recurrence. In this dissertation, we have systematically enriched, identified and characterized HCC cancer stem cells (CSCs) from 3 different HCC cell lines (Hepa1-6, HepG2, and Hep3B) using in vitro serum-free culture method. Enriched spheroids acquired CSC properties, primarily self-renewal capability, spheroid formation ability, and drug resistance. Heterogeneous CSCs enriched from Hepa1-6 cells demonstrated higher tumor initiation and proliferation capability in vivo, compared to control HCC cells in orthotopic immunocompetent mouse model. EpCAM+ CSCs were significantly enriched within heterogeneous Hepa1-6 CSC spheroids. Consequently, …

A New Surgical Approach For O-C2 Fusion, Solving The Problem Of Dysphagia., M. Kathryn Mcclure

Electronic Theses and Dissertations

The fusion of the second cervical vertebrae to the occipital bone (O-C2 fusion) for head stabilization can result in postoperative dysphagia and dyspnea, negatively impacting the patient’s quality of life. Currently, the O-C2 angle is used for head placement, which may not place the head neutrally. We hypothesize that aligning the external auditory meatus with midline of the C2 will reduce oropharyngeal stenosis, reducing dysphagia. One male patient with poor swallow quality of life who required a revision of a previous O-C2 surgery was evaluated via videofluoroscopy and completed the standard swallow quality of life questionnaire (SWAL-QOL) before and after …

Designing Interactive Virtual Environments With Feedback In Health Applications., Yi Li

Electronic Theses and Dissertations

One of the most important factors to influence user experience in human-computer interaction is the user emotional reaction. Interactive environments including serious games that are responsive to user emotions improve their effectiveness and user satisfactions. Testing and training for user emotional competence is meaningful in healthcare field, which has motivated us to analyze immersive affective games using emotional feedbacks. In this dissertation, a systematic model of designing interactive environment is presented, which consists of three essential modules: affect modeling, affect recognition, and affect control. In order to collect data for analysis and construct these modules, a series of experiments were …

Comparing Total Expenditures By Source Of Long-Term Services And Supports., Maresa R. Corder

Electronic Theses and Dissertations

This study compares total expenditures between beneficiaries enrolled in traditional Long-Term Care (LTC) and beneficiaries enrolled in Home and Community Based Services (HCBS) in a Quasi-Experimental Simple Ex Post Facto study utilizing multiple linear regression with inverted propensity score weighting. The results demonstrated, during the two years of the study period, that total expenditures were on average $14,565.03 (with a p-value oflessfor the total two years of the study, for HCBS beneficiaries when compared to their LTC counterparts. There remains today a belief that expenditures of elderly, dual beneficiaries electing to age-in-place for supported self-care expend less than that of …

Biomechanical Testing Of An Exercise For Strengthening The Proximal Femur., Alyssa Osbourne

Electronic Theses and Dissertations

Based on the principles of cutting edge bone remodeling research, a unique therapeutic exercise device was designed specifically to improve bone quality at the most critical location of the proximal femur prone to fracture: the superior-lateral femoral neck where the fracture first initiates during a fall. The exercise/device is intended to work by inducing enough strain in the bone to stimulate the body’s natural bone remodeling mechanisms to increase bone density in the proximal femur and consequently prevent a fracture from arising if a fall to the side does occur.

In order to test the proposed exercise, experiments simulating the …

Custom Software For The 3d Printing Of Patient Specific Plate Bending Templates In Pelvic Fracture Repair., Gordon B Lents

Electronic Theses and Dissertations

The purpose of this work is to reduce the operative time and blood loss incurred during open reduction and internal fixation (ORIF) of traumatic pelvic injuries through the creation of patient specific bending templates for reconstruction plates. These templates are 3D printed in a resin capable of being sterilized and taken into the operating room so that bending may be performed by the surgeon before the patient is opened or by another team member in parallel with the surgeon.

A novel software extension was created in 3D modeling software to allow a surgeon to individually position screws on a pelvic …

Spinal Cord Injury Induced Cardiac Decline And The Limitations Of Exercise., Kathryn Michele Deveau

Electronic Theses and Dissertations

There is a general consensus that the level and the severity of spinal cord injury (SCI) impacts chronic cardiac abnormalities such that high thoracic and cervical SCI are the most severely affected. Furthermore, the extreme degree of immobility/inactivity experienced by the persons with SCI has implications on cardiac decline. Yet it has been difficult to separate the relative contributions of the decentralized autonomic nervous system (ANS) and the immediate and profound inactivity to chronic cardiac abnormalities. As such, this body of work sought to characterize a contusion SCI that results in persistent CV dysfunction. Echocardiography, Dobutamine stress echocardiography and pressure …

Targeting The Glucose Metabolism Of Myeloid-Derived Suppressor Cells (Mdscs) To Stimulate Cancer Immunity., Jaspreet Grewal

Electronic Theses and Dissertations

Myeloid derived suppressor cells (MDSCs) are a heterogeneous group of immature myeloid cells that are significantly increased in cancer patients and correlate with higher stage and poor prognosis. MDSCs negatively modulate anti-tumor immunity, suppress T cell activity, promote angiogenesis and increase the risk of metastasis. In this study, we report that monocytic-MDSCs (M-MDSCs) but polymorphonuclear-MDSCs (PMN-MDSCs) over-express 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatases 3 (PFKFB3), an important regulator of glycolysis. Furthermore in the melanoma model, M-MDSCs but not PMN-MDSCs suppressed T cell function which correlated with PFKFB3 over-expression and increased rate of glycolysis. PFKFB3 inhibition with the first-in-class small molecule inhibitor, PFK-158 reversed M-MDSC …

Enhancing Cell Therapy For Ischemic Cardiomyopathy., Michael J. Book

Electronic Theses and Dissertations

Cardiac cell therapy using cardiac mesenchymal cells (CMC) significantly reduces ventricular dysfunction in patients with ischemic cardiomyopathy. Despite the improvement in function, a modest number of CMCs survive in the heart post-transplantation. In this study, we sought to improve the survival and retention of transplanted CMCs to prolong the therapeutic benefits afforded by cardiac cell therapy. To do this, we targeted the enzyme telomerase (TERT), known to be active in some highly proliferating cells (e.g. germ, stem). TERT is responsible for preventing telomere attrition, thereby allowing continued proliferation. TERT has also been shown to be protective, improve cell migration and …

The Role And Regulation Of Inhibitor Of Kappa B Kinase In The Impaired Monocyte Response., Norman James Galbraith

Electronic Theses and Dissertations

Trauma, major surgery and systemic infection can lead to a subsequent immunosuppressed state which can predispose patients to nosocomial infection and death. Approximately a sixth of patients will have impaired monocyte function, as determined by decreased HLA-DR expression or decreased TNF-α production in response to ex-vivo lipopolysaccharide (LPS) stimulation. This project aimed to develop an in-vitro model of impaired monocyte function using isolated monocytes from healthy volunteers, to study the effect of monocyte impairment on IκK signaling, and determine the role of IκK in the impaired monocyte response. These studies have provided the following results:

1. Monocytes treated with low dose …

Evaluating Cardiovascular Dysfunction During Increased Activity And Exercise Rehabilitation Following Incomplete Thoracic Spinal Cord Injury In The Adult Rat., Kathryn A. Harman

Electronic Theses and Dissertations

Spinal cord injury (SCI) results in whole-body dysfunction. While the majority of SCI research is focused on improving locomotor function after injury, cardiovascular (CV) disease continues to be the leading cause of morbidity in the chronic SCI patient population. The combination of injury-induced destruction of autonomic pathways, maladaptive plasticity within lumbosacral circuits, and the progressive decline in physical fitness contribute to the poor CV status of SCI individuals. Currently, there is little emphasis on implementing appropriately-timed acute rehabilitation techniques aimed to curtail maladaptive remodeling and improve CV outcomes. Furthermore, no pre-clinical or clinical studies have investigated the most appropriate time-course …