Medicine and Health Sciences Commons^™

Bayesian Methods For Graphical Models With Neighborhood Selection., Sagnik Bhadury

Electronic Theses and Dissertations

Graphical models determine associations between variables through the notion of conditional independence. Gaussian graphical models are a widely used class of such models, where the relationships are formalized by non-null entries of the precision matrix. However, in high-dimensional cases, covariance estimates are typically unstable. Moreover, it is natural to expect only a few significant associations to be present in many realistic applications. This necessitates the injection of sparsity techniques into the estimation method. Classical frequentist methods, like GLASSO, use penalization techniques for this purpose. Fully Bayesian methods, on the contrary, are slow because they require iteratively sampling over a quadratic …

An Enhancement To Cnn Approach With Synthesized Image Data For Disease Subtype Classification, Narider Pal Singh

Electronic Theses and Dissertations

The introduction of genetic testing has profoundly enhanced the prospects of early detection of diseases and techniques to suggest precision medicines. The subtyping of critical diseases has proven to be an essential part of the development of individualized therapies and has led to deeper insights into the heterogeneity of the disease. Studies suggest that variants in particular genes have significant effects on certain types of immune system cells and are also involved in the risk of certain critical illnesses like cancer. By analyzing the genetic sequence of a patient, disease types and subtypes can be predicted. Recent research work has …

Deciphering The Perpetual Fight Between Virus And Host: Utilizing Bioinformatics To Elucidate The Host's Genetic Mechanisms That Influence Jc Polyomavirus Infection, Michael P. Wilczek

Electronic Theses and Dissertations

JC polyomavirus (JCPyV) is a human-specific pathogen that infects 50-80% of the population, and can cause a deadly, demyelinating disease, known as progressive multifocal leukoencephalopathy (PML). In most of the population, JCPyV persistently infects the kidneys but during immunosuppression, it can reactivate and spread to the central nervous system (CNS), causing PML. In the CNS, JCPyV targets two cell types, astrocytes, and oligodendrocytes. Due to the hallmark pathology of oligodendrocyte lysis observed in disease, oligodendrocytes were thought to be the main cell type involved during JCPyV infection. However, recent evidence suggests that astrocytes are targeted by the virus and act …

Characterization Of Adiposity And Inflammation Genetic Pleiotropy Underlying Cardiovascular Risk Factors In Hispanics., Mohammad Yaser (Anwar)

Electronic Theses and Dissertations

The observed overlap between genetic variants associated with both adiposity and inflammatory markers suggests that changes in both adiposity and inflammation could be partially mediated by common pathways. The pervasive but sparsely characterized “pleiotropic” genetic variants associated with both adiposity and inflammation have been hypothesized to provide insight into the shared biology. This study explored and characterized the genetic pleiotropy underpinning adiposity and inflammation using genetic and phenotypic observations from the Cameron County Hispanic Cohort (CCHC). A total of 3,313 samples and >9 million single nucleotide polymorphisms (SNPs) were examined in this study. Mixed model genome-wide association studies (GWAS) were …

Human Genetics, Psychotropic Drugs, And Acts Of Violence, Selma Jolanda Eikelenboom-Schieveld

Electronic Theses and Dissertations

From the start of the use of psychoactive prescription medications in the 1950s, physicians reported paradoxical adverse reactions, ranging from newly developing depressions to an increase in existing mood disorders, and extremely violent and bizarre acts of suicide and homicide. In this research, it is hypothesized that the pharmacological properties of the prescribed drugs or the interaction between the drugs and the enzymes that are primarily responsible for their metabolism (cytochrome P450s) could cause these reactions. Given that acts of violence could be medication-induced, the role of the rate of drug metabolism is discussed. Genetic testing of certain CYP450s could …

Performance Differences Between Two Groups Of Commercial Pigs Following Experimental Infection With Prrs Virus 1-7-4, Erin Little

Electronic Theses and Dissertations

Porcine reproductive and respiratory syndrome virus (PRRSV) is the costliest swine disease in North America. Vaccines and management alone have not been effective in controlling this disease. Genetic selection for resilience may be a complimentary approach for controlling PRRSV. The objective of this study was to estimate performance differences between two groups of pigs from the same commercial line following infection with PRRSV 1-7-4: 1) pigs sired by boars selected based on a standard index (TN-S), which emphasized feed efficiency and carcass quality; and 2) pigs sired by boars selected based on an experimental index (TN-E), which emphasized feed intake, …

The N-Terminal Methyltransferase Homologs Nrmt1 And Nrmt2 Exhibit Novel Regulation Of Activity Through Heterotrimer Formation., Jon David Faughn

Electronic Theses and Dissertations

Protein, DNA, and RNA methyltransferases have an ever-expanding list of novel substrates and catalytic activities. Even within families and between homologs, it is becoming clear the intricacies of methyltransferase specificity and regulation are far more diverse than originally thought. In addition to specific substrates and distinct methylation levels, methyltransferase activity can be altered through formation of complexes with close homologs. This work involves the N-terminal methyltransferase homologs NRMT1 and NRMT2. NRMT1 is a ubiquitously expressed distributive trimethylase. NRMT2 is a monomethylase expressed at low levels and in a tissue-specific manner. They are both nuclear methyltransferases with overlapping target consensus sequences …

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 …

Precision Gene Therapy For Charcot-Marie-Tooth Disease: From Identifying Genetic Modifiers To Developing Allele-Specific Therapies, Kathryn H. Morelli Ph.D.

Electronic Theses and Dissertations

Charcot-Marie-Tooth Disease (CMT) is a clinically and genetically heterogeneous collection of inherited peripheral neuropathies generally characterized by progressive muscle atrophy, weakness, and loss of sensation in the distal extremities. This inherited disorder, for which there is currently no curative treatment, is the most common inherited disease of the peripheral nervous system, affecting 1:2,500 individuals worldwide.

Clinically, CMT is broadly divided into demyelinating (type 1) and axonal (type 2) forms. Although the clinical presentation can vary greatly in severity and progression within individual patients. Genetically, over 1,000 mutations in over 80 loci in the human genome have been linked to specific …

Functional And Structural Impact Of The Loss Of The Leucine-Rich Repeat Protein Lrit1 In The Mouse Retina., Catherine Ann Cobb

Electronic Theses and Dissertations

Mutations in genes encoding the leucine-rich repeat (LRR) proteins nyctalopin and LRIT3 lead to complete congenital stationary night blindness because they are critical to depolarizing bipolar cell function in the retina. LRIT3 has two closely related family members, LRIT1 and LRIT2. In silico analyses of publicly available RNA-Seq data showed that Lrit1 was highly expressed in the retina. Here I describe the expression pattern and impact of loss of LRIT1 on retinal function. To enable these studies, we used CRISPR/Cas9 technology to create an Lrit1^-/- mouse line. Retinal morphology and morphometry analyses showed no gross changes in retinal structure …

Expression Profiling Of Non-Coding Rna By Environmental Interactions In Innate Immunity, Jacob R. Longfellow

Electronic Theses and Dissertations

Cystic fibrosis (CF) is a genetic disorder that affects 30,000 people in the United States and currently has no cure. Although CF affects all of the body’s systems, it is largely characterized as a lung disease. CF is caused by a mutation in both copies of the gene for cystic fibrosis transmembrane conductance regulator (CFTR). A mutation in the CFTR gene leads to improper movement of chloride ions and water into the airways, which dysregulates the airway surface liquid volume and composition. Individuals with CF are prone to lung infections due to inefficient bacterial clearance and by the age of …

Effects Of Melatonin On Heartbeat And Possible Identification Of A Melatonin Receptor In Drosophila Melanogaster, Tricia L. Vankirk

Electronic Theses and Dissertations

Chapter 1 of this manuscript is a literature review that serves as an introduction to the entire dissertation. Chapter 2 examines the effects of the melatonin injection on heart rate and rhythmicity in Drosophila melanogaster Canton-S (wild-type) pupae and pupae bearing a variety of heart mutations. Chapter 3 investigates further the possible mechanisms of melatonin’s ability to increase heart rhythmicity without significantly affecting heart rate. A melatonin antagonist, luzindole; a high-affinity melatonin agonist, 2-iodomelatonin and RNAi techniques are used to identify a possible melatonin receptor in Drosophila melanogaster.

An appendix contains a previously published manuscript detailing experiments performed at the …

Genetic Imbalances In Endometriosis Detected By Oligonucleotide-Array Based Comparative Genomic Hybridization, Natalie Burke

Electronic Theses and Dissertations

Endometriosis is one of the most common gynecological diseases as it is thought to affect up to 15% of the female population. Characterized by the growth and proliferation of endometrial tissue outside of the uterine cavity, it is a complex condition with varying degrees of severity and can affect multiple regions of the body with symptoms ranging from a total lack of symptoms to debilitating pain and infertility. The most accepted theory of how endometriosis initiates is that of retrograde menstruation; however, approximately 90% of women with unobstructed fallopian tubes are thought to have some menstrual debris in the peritoneal …