Medicine and Health Sciences Commons^™

Investigation Of Orthohantavirus Genetics In Rodent Reservoirs And Clinical Samples, Samuel M Goodfellow

Biomedical Sciences ETDs

Orthohantaviruses are negative-sense, single stranded RNA viruses with trisegmented genomes that can cause severe disease in humans and are carried by several host reservoirs throughout the world. In the United States, Sin Nombre orthohantavirus (SNV) is the primary cause of hantavirus cardiopulmonary syndrome (HCPS) with a fatality rate of ~36% and the highest cases occuring in the southwest region. The primary SNV host reservoir is thought to be the western deer mouse, Peromyscus maniculatus, however it has been shown that other rodents can carry different orthohantaviruses. We designed a pan-orthohantavirus detection tool to survey several small mammal populations throughout New …

Determining The Existence And Regulation Of Microlipophagy In Primary Brown And White Adipocytes, Sara C. Arenas De Leon

Biomedical Sciences ETDs

Lipids are one of life’s four main macromolecules and provide essential functions to cells.

The degradation of lipid droplets and mobilization of lipids occurs through lipolysis. Emerging evidence demonstrates evidence of a selective form of autophagy in lipolysis. The process of microlipophagy has only recently been described, and many features of its regulation are still poorly understood. Our recent study showed that inhibiting mammalian target of rapamycin complex 1 (mTORC1) pathway by depletion of Raptor in adipocytes led to an influx of lysosomes and accumulation of lipid droplets within lysosome. Here, we expand on these previous findings. We were able …

Effects Of Acute And Chronic Gut Injury On Secretory Lineage Differentiation, Roger Atanga

Biomedical Sciences ETDs

Acute and chronic injury to the gut has several detrimental consequences. However, dysregulation of secretory lineage cells is a common observation. To model acute gut injury, we use non-fissile uranium bearing dust (UBD), an environmental toxicant prevalent in communities adjacent abandoned uranium mines, majority of which are located in the Southwestern United States. Repeated exposure to environmental toxins and heavy metals has been obscurely linked to intestinal inflammation, increased susceptibility to pathogen-induced diseases, and higher incidences of colorectal cancer. However, there is no molecular evidence that non-fissile uranium can cause damage to the intestinal epithelia. Human colonoids exposed to UBD …

Determining The Existence And Regulation Of Microlipophagy In Primary Brown And White Adipocytes, Sara C. Arenas De Leon

Biomedical Sciences ETDs

Lipids are one of life’s four main macromolecules and provide essential functions to cells, as they serve as building blocks of cellular membranes, mediate cell signaling, and are a critical energy source. Within cells, esterified fatty acids aggregate into lipid droplets in the form of triglycerides, consisting of a neutral lipid core surrounded by a phospholipid monolayer decorated with various proteins.

The degradation of lipid droplets and mobilization of lipids occurs through lipolysis, a process that hydrolyzes a molecule of triglyceride into a glycerol and three fatty acids. Emerging evidence demonstrates the involvement of a selective form of autophagy in …

Neuroinflammatory And Metabolomic Temporal Dynamics From Inhaled Wildfire Smoke With Attenuation Via Pharmacological Intervention, David Scieszka, David Scieszka

Biomedical Sciences ETDs

Wildfire smoke is a global issue affecting nearly all humans on the surface of this Earth. Smoke dispersion from wildfires can span continents and cross oceans with amazing ease. Furthermore, total acres of land burned per year in the United States has roughly doubled since 1980, meaning this issue will persist for an indeterminate amount of time. Exposure to wildfire smoke is hazardous and promotes aging-associated events in the cardiopulmonary systems. Yet long- and short-term effects on the brain remain relatively unknown. From these, it is critically important to understand the neurological impacts from wildfire smoke exposure; to compare these …

Comparative Genomics Methods And Applications, Emily N. Alden

Biomedical Sciences ETDs

Virtually all fields of biology have benefited from the advancements in comparative genomics technologies, specifically in the study of evolution. In this dissertation I develop and use comparative genomic technologies to investigate the novel SARS-CoV-2 virus, assembly the first genome of the black lace domestic angelfish and identify germline genetic variants associated with altered breast cancer-specific survival. Our genome tiling array for the novel coronavirus presents a rapid and cost-effective method to sequence the entire viral genome and can be used to track the rapid evolution of viral variants in the population. The domestic angelfish is a member of the …

Sexual Dimorphism In Host Innate Response To Staphylococcus Aureus: Mechanisms Driving Sex Differences In Immune Cell Function And Host-Directed Interventions, Srijana Pokhrel

Biomedical Sciences ETDs

With the emerging antibiotic resistance, Staphylococcus aureus, primary causative agent of skin and soft tissue infections (SSTIs) as well as other life-threatening conditions has become a global health concern. While factors contributing to host defense against S. aureus SSTIs has been well studied, impact of sex as a variable has not been reported. In Chapter 2, we uncover the sex-specific differences in host response to S. aureus SSTIs and the contribution of female sex hormone, estrogen (E2) in providing protection in females. In Chapter 3, we identify mechanisms of innate differences in neutrophils bactericidal efficacy between sexes and in …

Translating Touches: New Approaches For Modeling And Rescuing Executive Function Deficits After Prenatal Alcohol Exposure, Johnny A. Kenton

Biomedical Sciences ETDs

Background: With a recent meta-analysis indicating that 9.8% of women worldwide consume alcohol during pregnancy, understanding the effects of fetal alcohol spectrum disorder (FASD) is critical for both identifying and treating those afflicted. Traditional preclinical research investigating the behavioral effects of neurodevelopmental disorders, such as FASD, has utilized tasks designed for specific animal models. For this reason, preclinical research into FASD requires a shift into clinically relevant behavioral testing. One such method involves touch-sensitive screens integrated into an operant box to emulate clinical computer-based tasks, such as the Cambridge Neuropsychological Test Automated Battery.

Methods: Here, we utilized a mouse model …

Cold-Inducible Rna Binding Protein (Cirp) Impedes Proliferation And Inflammation In The Pymt Mouse Model For Breast Cancer, Daniel Albino Lujan

Biomedical Sciences ETDs

RNA binding proteins (RBPs) regulate gene expression by controlling mRNA export, translation, and stability. When altered, some RBPs allow cancer cells to grow, survive, and metastasize. Cold-inducible RNA binding protein (CIRP) is overexpressed in a subset of breast cancers, induces proliferation in breast cancer cell lines, and inhibits apoptosis. We generated a transgenic mouse model overexpressing human CIRP in the mammary epithelium to ask if it plays a role in mammary gland development. We also assessed the effects of CIRP on breast tumorigenesis using breeding crosses with the PyMT mouse model for breast cancer. CIRP decreased proliferation at the lactational …

Mechanisms And Consequences Of Myb Gene Activation In Salivary Gland Tumors, Candace Frerich

Biomedical Sciences ETDs

Salivary gland adenoid cystic carcinoma (ACC) is an aggressive tumor with a tendency to infiltrate surrounding nerves and metastasize to distant sites. The standard treatment often fails to control local tumor recurrence and distant metastases and no approved targeted therapeutic options exist for these tumors. The goal of our studies was to reveal the molecular mechanisms driving ACC tumor development and novel drug targets to improve patient morbidity and mortality.

We first analyzed clinical and RNA-sequencing (RNA-seq) data for 68 formalin-fixed paraffin-embedded (FFPE) ACC tumor samples and described previously unappreciated molecular heterogeneity that predicts patient outcome. The poor outcome subgroup …

Neuron Specific Gene 2 (Nsg2): A Novel Regulator Of Excitatory Neurotransmission Via Ampa Receptor Trafficking At A Subset Of Glutamatergic Synapses, Praveen Chander

Biomedical Sciences ETDs

Members of the Neuron-Specific Gene family (NSG1-3) play critical roles in excitatory synaptic transmission via regulation of AMPA receptor surface expression within the post-synaptic density (PSD). While NSG1 and NSG3 regulate AMPAR recycling and endocytosis, respectively, the function of NSG2 has remained elusive. Here we undertook a series of studies to assess the role of NSG2 in excitatory synaptic transmission. We found that a portion of NSG2 punctae localized with HOMER1 and surface AMPARs at excitatory synapses and that NSG2 AMPAR subunits in mouse brain. Knockout of NSG2 selectively impaired the frequency of AMPA mEPSCs, while overexpression caused a significant …

The Role Of Omega-3 Polyunsaturated Fatty Acids In Blood Pressure Regulation And Secondhand Smoke-Induced Vascular Dysfunction, Emily Anna Wheeler

Biomedical Sciences ETDs

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) may lower cardiovascular disease risk by reducing blood pressure (BP). We hypothesized that fat-1 transgenic mice, which convert n-6 PUFAs to n-3 PUFAs, would have improved vascular function in BP regulation and following secondhand smoke (SHS) exposure, compared to wild type (WT) mice.

BP was recorded in mice fed an n-6 PUFA, or standard chow diet. On the n-6 PUFA diet fat-1 mice had a lower mean arterial pressure and a greater decrease in diastolic BP when treated with an ACE inhibitor, compared to WT mice. No differences were observed on the chow diet. …

The Role Of Adaptive Immunity In Chronic Hypoxia-Induced Pulmonary Hypertension, Levi David Maston

Biomedical Sciences ETDs

Inflammation is a prominent pathologic feature in pulmonary arterial hypertension as demonstrated by pulmonary vascular infiltration of inflammatory cells, including T and B lymphocytes. However, the contribution of the adaptive immune system is not well characterized in pulmonary hypertension (PH) caused by chronic hypoxia (CH). Inflammatory cells, through various mechanisms, have the capability to increase pulmonary vascular resistance in various disease states. CD4⁺T cells have the potential to play a significant role in the disease process initiated by hypoxia. CD4⁺T cells are largely responsible for orchestrating downstream immune processes and are critical in focusing and amplifying …

Intratypic Genetic Variability Of Human Adenovirus Type 4: Implication For Viral Pathogenesis, Camden Roy Bair

Biomedical Sciences ETDs

Human adenovirus type 4 (HAdV-E4) is a causative agent of acute respiratory disease and conjunctivitis worldwide. Two major lineages of HAdV-E4 genomic variants have been identified by their distinct BamHI restriction profiles: prototype-like (p-like) strains and the a-like genomic variants. Recent molecular epidemiology studies have shown a predominance of a-like genomic variants detected in association with disease which suggests a-like strains have a fitness advantage or they may be more pathogenic. The impact of HAdV-E4 intratypic genetic variability on in vitro and in vivo phenotypes relevant to pathogenesis is a major gap in knowledge. I hypothesize that HAdV-E4 comprises two …

Determining The Pathological Effects Of Prenatal Alcohol Exposure On Peripheral Neuropathy Via Spinal And Peripheral Immune Mechanisms, Joshua J. Sanchez

Biomedical Sciences ETDs

Previous studies have suggested that children with Fetal Alcohol Spectrum Disorder (FASD) display hypersensitivity to light touch. In support of this notion, we have demonstrated that applying a chronic constriction injury (CCI) to the sciatic nerve of rats that have prenatal alcohol exposure (PAE) results in heightened sensitivity to light touch, clinically termed allodynia. These observations coincided with heightened glial activation and enhanced peripheral immune reactivity. Considering allodynia is known to be mediated by both peripheral immune responses and spinal glial activation, it is reasonable to speculate that allodynia following PAE may be mediated through an alteration of immune reactivity. …

Determining Mediators Of Naive T Cell Motility And Dc Association In The Lymph Node, Janie R. Byrum

Biomedical Sciences ETDs

To become activated and perform effector functions, naive T cells move within lymph nodes to scan dendritic cells presenting antigen. Previous work has shown naive T cell activation is promoted by interleukin 7 in vivo, and it does so by regulating the T cell:dendritic cell interaction. Our work identifies a novel role for IL-7 in mediating naive T cell motility in the lymph node and promoting T cell association with DCs. Additionally, we have developed a method for analyzing microscopy images, regionalized normalized mutual information, to assess intercellular associations between T cells and other cells within the lymph node. Dendritic …

Comprehensive Sequencing With Surface Tagmentation Based Technology, Kuan Feng

Biomedical Sciences ETDs

Next-generation sequencing technologies (NGS) have undergone extensive improvements since the invention of the 454 sequencing system in 2005. With tremendous progress in throughput, speed and a dramatic reduction in per-base cost, DNA sequencing is widely used in basic science as well as translational research. However, it is still a challenge to acquire a complete human genome. The long-range information is often missing due to the short length of NGS reads, which leaves many gaps in between scaffolds rather than an entire piece for each chromosome. Moreover, without the long-range information, haplotype-resolved genome sequencing and structural variant detection can be difficult, …

Developing Droplet Based 3d Cell Culture Methods To Enable Investigations Of The Chemical Tumor Microenvironment, Jacqueline A. De Lora

Biomedical Sciences ETDs

Adaptation of cancer cells to changes in the biochemical microenvironment in an expanding tumor mass is a crucial aspect of malignant progression, tumor metabolism, and drug efficacy. In vitro, it is challenging to mimic the evolution of biochemical gradients and the cellular heterogeneity that characterizes cancer tissues found in vivo. It is well accepted that more realistic and controllable in vitro 3D model systems are required to improve the overall cancer research paradigm and thus improve on the translation of results, but multidisciplinary approaches are needed for these advances. This work develops such approaches and demonstrates that new droplet-based cell-encapsulation …

Regulations Of Pathogenic Cd4+ T Helper Lymphocytes In Inflammatory Diseases, Handong Zheng

Biomedical Sciences ETDs

In this comprehensive project, three interrelated studies with distinct foci were employed to understand the regulations of specific CD4⁺ T helper cell population in inflammatory diseases.

Pathogenic TH17 cells play an essential role in the initiation and development of both human multiple sclerosis (MS) and animal experimental autoimmune encephalomyelitis (EAE). Nevertheless, the underlying mechanism by which the pathogenicity of TH17 cells is controlled in the autoimmune neuro-inflammation remains unclear. In aim 1, we revealed that lumican (Lum), an extracellular matrix (ECM) protein, negatively regulates encephalitic TH17 cell responses. Our findings highlighted a TH17 cell-intrinsic effect of Lum in suppressing …

Studying Egfr Signaling Through Single Molecule Imaging And Computational Modeling, Emanuel Salazar Cavazos

Biomedical Sciences ETDs

Signaling through the Epidermal Growth Factor Receptor (EGFR) plays an important role in both physiological and cancer-related processes. In this work, single-molecule microscopy measurements and computational modeling were closely integrated to better understand the mechanisms that regulate EGFR signaling. Technical improvements were made over the previously described Single-Molecule Pull-down (SiMPull) assay to facilitate direct detection of the phosphorylation state of thousands of individual receptors, and thereby estimate both the fraction of receptors phosphorylated at specific tyrosine residues and the frequency of multisite phosphorylation. These improvements enabled the first direct detection of multisite phosphorylation on full-length Epidermal Growth Factor Receptor (EGFR), …

Cholesterol Regulation Of Pulmonary Endothelial Calcium Entry Following Chronic Hypoxia, Bojun Zhang

Biomedical Sciences ETDs

Chronic hypoxia (CH)-induced pulmonary hypertension (PH) is associated with diminished ATP-induced endothelial Ca2+ entry as well as membrane cholesterol in pulmonary arteries. Store-operated Ca2+ entry (SOCE) and depolarization-induced Ca2+ entry are major components of the response to ATP and are similarly decreased after CH. Because endothelium-dependent vasodilation is closely associated with pulmonary endothelial [Ca2+]i, the blunted agonist-induced Ca2+ influx in pulmonary artery endothelial cells (PAEC) may contribute to the development of CH-induced PH. Interestingly, impaired agonist-induced Ca2+ influx in PAEC following CH can be restored by membrane cholesterol supplementation. In the current studies, we hypothesized that impaired Ca2+ entry in …

Exploring Biological Heterogeneity And Its Consequences At Tissue And Cellular Scales Through Mathematical And Computational Modeling, Romica Kerketta

Biomedical Sciences ETDs

This dissertation explores the effects of heterogeneity across different biological scales in cancer as well as normal cells. At the tissue scale, we investigated the variability present in the tumor microenvironment and its effect on patient chemotherapeutic outcomes using a mathematical model of drug transport. We found that parameters such as tumor blood perfusion and radius of blood vessel had an impact on the tumor cytotoxicity. This indicated that the physical microenvironment of the tumor is an important regulator of the tumor response to chemotherapy. At the cellular scale, we investigated the heterogeneity present on the membrane landscape of ErbB2 …

Cortico-Striatal Coordination Disrupted In Behaviorally Inflexible Moderate Prenatal Alcohol Exposed Mice, Kristin L. Marquardt

Biomedical Sciences ETDs

Up to 61% of adolescent school aged children with fetal alcohol spectrum disorder (FASD) have been suspended or expelled. Executive function deficits, like dis-inhibition and cognitive inflexibility, have been proposed to be better predictors of behavioral problems then IQ score, which qualifies these individuals for developmental disability and special school programs. Reversal learning, a widely used behavioral paradigm for assessing cognitive flexibility across species, has been shown to be impaired in rodent models of prenatal alcohol exposure (PAE). Here we show that a mouse model with daily maternal drinking, resulting in a BAC of 85 mg/dl throughout gestation, results in …

Cd82 Membrane Scaffolding Regulates Hematopoietic Cell Functions, Christina M. Termini

Biomedical Sciences ETDs

Through their ability to self-renew and differentiate, hematopoietic stem/progenitor cells (HSPCs) maintain the adult blood and immune systems. The microenvironment, or niche, in which HSPCs reside, serves as a critical regulator of HSPC functions. As previous work has identified the tetraspanin CD82 as a mediator of HSPC-niche interactions, we aimed to determine the mechanism by which this occurs. Our data demonstrate that CD82 expression and scaffolding regulate HSPC interactions with niche components by organizing the α4 integrin subunit into tightly packed nanoclusters. The HSPC niche can also protect acute myeloid leukemia (AML) cells from therapeutics. Therefore, we next examined how …

Validation Of The Pre-B Cell Receptor As A Therapeutic Target In B Cell Precursor Acute Lymphoblastic Leukemia, Michael F. Erasmus

Biomedical Sciences ETDs

This dissertation is built upon the fundamental idea that the pre-B cell receptor (pre-BCR) is important to leukemia cell survival and a logical therapeutic target in B cell precursor acute lymphoblastic leukemia (BCP-ALL). The pre-BCR is expressed early at a specific stage during B cell development where it plays a central role in survival of healthy B lymphocytes. This receptor is composed of the membrane heavy chain (mIgμ) associated with surrogate light chain components, 5 and VpreB. Through the use of advanced imaging modalities, in particular two-color single particle tracking (SPT), we showed that pre-BCRs formed transient, homotypic interactions. These …

Network Inference Driven Drug Discovery, Gergely Zahoránszky-Kőhalmi, Tudor I. Oprea Md, Phd, Cristian G. Bologa Phd, Subramani Mani Md, Phd, Oleg Ursu Phd

Biomedical Sciences ETDs

The application of rational drug design principles in the era of network-pharmacology requires the investigation of drug-target and target-target interactions in order to design new drugs. The presented research was aimed at developing novel computational methods that enable the efficient analysis of complex biomedical data and to promote the hypothesis generation in the context of translational research. The three chapters of the Dissertation relate to various segments of drug discovery and development process.

The first chapter introduces the integrated predictive drug discovery platform „SmartGraph”. The novel collaborative-filtering based algorithm „Target Based Recommender (TBR)” was developed in the framework of this …

The Role Of Fatty Acids And Cigarette Smoke Toxicants In Cigarette Smoke-Induced Cardiovascular Disease, Elani F. Wiest 4216058

Biomedical Sciences ETDs

Young, healthy smokers have an increased risk of developing cardiovascular disease (CVD), but early identification of these individuals can prevent progression to more severe cardiovascular diseases like atherosclerosis, stroke, and heart attacks. However, methods developed to detect cardiovascular disease in its early stages are limited and very costly. The goal of this project is to identify biomarkers that can be tested in a single blood draw from smokers in order to both assess their risk of developing cardiovascular disease and identify possible therapeutic targets to prevent disease progression.

The long term goals of this project are to investigate the association …