Digital Commons Network^™

High Affinity Block Of Icl,Swell By Thiol-Reactive Small Molecules, Sung H. Park

Theses and Dissertations

Ebselen (Ebs) is considered as a glutathione peroxidase (GPx) mimetic and primarily thought to function by scavenging intracellular reactive oxygen species (ROS). Previous to our work, Deng et al. (2010a) demonstrated complete block of I_Cl,swell with 15 microM Ebs following endothelin-1 (ET-1) induced activation of the current in cardiomyocytes. This block was presumed to take effect mainly via the quenching of ROS. Nonetheless, our work with DI TNC1 astrocytes strongly emphasizes that Ebs might function by an alternative mechanism based on its kinetic profile in blocking I_Cl,swell. Our experiments showed that 45 nM Ebs can fully block …

Conditional Cardiac-Specific Akap13 Knockout Induces Sex Dependent Biventricular Dilated Cardiomyopathy With Sarcomeric And Mitochondrial Defects, Kimberlyn M. Baig-Ward

Theses and Dissertations

Heart disease is a complex and heterogeneous disease. Notably, studies have demonstrated gender differences in the expression and types of cardiovascular disease, such as dilated cardiomyopathy (DCM), a major underlying cause of heart failure. Previously we showed that loss of A-Kinase Anchoring Protein 13 (Akap13), a unique proto-oncogene and estrogen receptor modulator, resulted in enlarged embryonic hearts, defective cardiac sarcomere formation, and embryonic lethality in mice. Data have also shown cAMP-dependent Protein Kinase A (PKA) to be involved in DCM pathophysiology. Given the established role of AKAP13 in cell signaling, its ability to bind and modulate ligand-activated nuclear hormone …

The Microbiome In Light Of Host Evolution, Alexander M. Waldrop Jr.

Theses and Dissertations

Recent advances in sequencing technologies have provided an unprecedented window in the unseen biological world. Accompanying this revolution is a growing appreciation for the ubiquity and diversity of beneficial interactions between animals and the microbes they carry. Given the symbiotic roles of microbes in host nutrition, immunity, behavior, development, and nearly every other facet of host biology, it is becoming increasingly clear that any understanding of hosts and their evolution would be incomplete without also considering the microbial dimension. Yet despite the growing body of evidence that many of these partnerships are rooted deep in evolutionary time, the majority of …

Independent Origination Of Floral Zygomorphy, A Predicted Adaptive Response To Pollinators: Developmental And Genetic Mechanisms, Ghadeer Bukhari, Wenheng Zhang

Theses and Dissertations

Observations of floral development indicate that floral organ initiation in pentapetalous flowers more commonly results in a medially positioned abaxial petal (MAB) than in a medially positioned adaxial petal (MAD), where the medial plane is defined by the stem and the bract during early floral development. It was proposed that the dominant MAB petal initiation might impose a developmental constraint that leads to the evolution of limited patterns of floral zygomorphy in Asteridae, a family in which the floral zygomorphy develops along the medial plane and results in a central ventral (CV) petal in mature flowers. Here, I investigate whether …

Power Analysis In Applied Linear Regression For Cell Type-Specific Differential Expression Detection, Edmund Glass

Theses and Dissertations

The goal of many human disease-oriented studies is to detect molecular mechanisms different between healthy controls and patients. Yet, commonly used gene expression measurements from any tissues suffer from variability of cell composition. This variability hinders the detection of differentially expressed genes and is often ignored. However, this variability may actually be advantageous, as heterogeneous gene expression measurements coupled with cell counts may provide deeper insights into the gene expression differences on the cell type-specific level. Published computational methods use linear regression to estimate cell type-specific differential expression. Yet, they do not consider many artifacts hidden in high-dimensional gene expression …

Probing Allosteric, Partial Inhibition Of Thrombin Using Novel Anticoagulants, Stephen S. Verespy Iii

Theses and Dissertations

Thrombin is the key protease that regulates hemostasis; the delicate balance between procoagulation and anticoagulation of blood. In clotting disorders, like deep vein thrombosis or pulmonary embolism, procoagulation is up-regulated, but propagation of clotting can be inhibited with drugs targeting the proteases involved, like thrombin. Such drugs however, have serious side effects (e.g., excessive bleeding) and some require monitoring during the course of treatment. The reason for these side effects is the mechanism by which the drugs’ act. The two major mechanisms are direct orthosteric and indirect allosteric inhibition, which will completely abolish the protease’s activity. Herein we sought an …

Effects Of Olfactory Cues On The Movement Behavior Of The Predatory Beetle Calosoma Wilcoxi, Kennesha Myrick-Bragg

Theses and Dissertations

Arthropod predators often use prey and conspecific cues to make foraging decisions. Calosoma wilcoxi (Leconte) is a voracious predatory beetle that specializes on lepidopteran larvae often found in the forest canopy, including the fall cankerworm. This study tested the hypothesis that C. wilcoxi uses olfactory cues to detect prey and conspecifics. A Y-tube olfactometer was used to test attractiveness to larvae, larval frass, conspecific cues, and volatiles from herbivore-damaged white oak leaves. C. wilcoxi did not preferentially choose the treatment in any of the experiments. There was no difference in mean time spent in the treatment or control arm for …

Investigating The Mechanism Of The Compartmentalized Cbp (Creb-Binding Protein) Ubiquitin Ligase Activities, Oluwatoyin E. Akande

Theses and Dissertations

CBP (CREB Binding Protein) is global transcriptional co-activator and histone acetyltransferase. CBP is involved in the modulation of the transcription of many genes via histone acetylation at the promoter regions of the target genes. Also, non-histone proteins and transcription factors can be acetylated by CBP to promote their transcriptional activation. In addition to its transcription co-activator role, CBP is involved in many other pathological and physiological cellular processes such as cell growth and differentiation, cell transformation and development, response to stress, cell cycle regulation and apoptosis.

CBP and its paralogue p300, play double-edged roles in the regulation of p53, a …

Allosteric Effects Of G-Protein Coupled Receptor Heteromerization: Relevance To Psychosis, Jason W. Younkin

Theses and Dissertations

G-protein coupled receptors (GPCRs) implicated in disease are the predominant pharmaceutical targets. Growing evidence suggests that GPCRs form homo- and heteromeric complexes, resulting in allosteric functional changes. Ligands targeting one receptor can alter the function of the other receptor or receptors. Knowledge of these functional changes will provide unique opportunities to treat diseases. We examined two GPCR heteromers implicated in psychosis: mGlu2R-5HT2AR and D2R-5HT2AR. Using whole-cell patch clamp, we studied HEK-293 cells stably transfected with mGlu2R and 5HT2AR. Maximal heteromer formation allows inverse agonists to increase the G-protein activity of the opposite receptor, while sub-maximal heteromer formation does not. However, …

Upper Thermal Limits Differ Among Component Species In A Host-Parasitoid-Hyperparasitoid System, Kanchan A. Joshi

Theses and Dissertations

Among the predicted impacts associated with global climate change, warming is of special interest because the rates of physiological processes are temperature-dependent. Insects and other ectotherms are likely to be affected due to their limited ability to control body temperature. In this study, I measured the tolerance to extreme high temperatures, i.e., critical thermal maximum (CT_max), of component species in a tri-trophic system, including an herbivore (Manduca sexta), a primary larval parasitoid (Cotesia congregata) and a hyperparasitoid (genus Silochalcis). For wild insects, the parasitoid had the lowest CT_max, the hyperparasitoid had …

Predictors Of Caffeine-Related Withdrawal Symptoms In College Freshmen, David J. Pomm

Theses and Dissertations

While caffeine withdrawal has been well-characterized, research on caffeine intake and factors associated with withdrawal has been limited. The present study examined prevalence rates of caffeine use and identified psychosocial factors associated with having caffeine withdrawal headaches (CWH). Participants were N = 1,989 college freshmen who participated in the 2011 Spit for Science project. Caffeine use was reported by 80% of the sample. Females were more likely than males to consume caffeine, and soda was the primary source of caffeine for both genders. As hypothesized, daily caffeine users were more likely to report CWH than non-daily users. When multivariable analyses …

Response Of Soil Microbial Communities To Saltwater Intrusion In Tidal Freshwater Wetlands, Chansotheary Dang

Theses and Dissertations

Saltwater intrusion due to global change is expected to have a detrimental effect on the biogeochemistry of tidal freshwater wetlands. Of particular concern is that fact that salinization can alter the role of these ecosystems in the global carbon cycling by causing shifts in microbial metabolism that alter greenhouse gas emissions and increase carbon mineralization rates. However, our understanding of how wetland microbial community dynamics will respond to saltwater intrusion is limited. To address this knowledge gap and increase our understanding of how microbial communities in tidal freshwater wetlands change over time (1, 3, 12, and 49 weeks) under elevated …

Evaluation Of Redox Potential As A Novel Biomarker Of Oxidative Stress, Inflammatory Response, And Shock Using Nanoporous Gold Electrodes, Matthew C. Ellenberg

Theses and Dissertations

EVALUATION OF REDOX POTENTIAL AS A NOVEL BIOMARKER OF OXIDATIVE STRESS, INFLAMMATORY RESPONSE, AND SHOCK USING NANOPOROUS GOLD ELECTRODES

Background: Redox potential is a chemical species’ affinity for electrons. Increased oxidant concentration is associated with disease1,2, yet there is not a way to measure systemic redox status.3 Redox potentiometry uses metal electrodes that do not work in blood because protein molecules adhere on the metal surface, blocking electron exchange.

Methods: Nanoporous gold electrodes have large surface areas that allowed electron exchange to continue in blood.4 Redox potential was measured in blood with ascorbic acid, in cardiac bypass patients and pigs …

Role Of The Exopolysaccharide Alginate In Adherence To And Inflammation Of Pulmonary Epithelial Cells, Brian E. Crossley

Theses and Dissertations

Pseudomonas aeruginosa (PA) infections in Cystic Fibrosis (CF) patients are not easily cleared due to the conversion from a nonmucoid to a mucoid phenotype. Alginate is an acetylated exopolysaccharide produced by mucoid PA that is responsible for increased resistance to antibiotics, host phagocytic killing, and propagating biofilm formation. Understanding the interaction between PA and host cells is critical to understanding chronic infection and inflammation in CF. In order to investigate this, we used A549 pulmonary epithelial cells and murine alveolar macrophages (MH-S) to examine host response to nonmucoid versus mucoid PA infection. Adhesion assays in A549 pulmonary epithelial cells revealed …

Stains Induce Apoptosis And Autophagy In Primary And Transformed Mast Cells, Patrick A. Paez

Theses and Dissertations

Statin drugs are widely employed in the clinic to reduce serum low density lipoproteins (LDLs) in patients with hypocholesteremia. In addition to their cholesterol-lowering effects through HMG CoA reductase antagonism, isoprenyl lipids necessary for membrane anchorage and signaling of small G-proteins are abrogated. We previously found that statins suppress mast cell activation in murine and human cells, suggesting these drugs might be useful in treating allergic disease. While mast cell function is critical to allergic inflammation, mast cell hyperplasia and survival also impact these diseases, and were not studied in our previous work. In this study, we describe Fluvastatin-mediated apoptosis …

From Seed To Sky: Impacts Of Explosive Compounds On Vegetation Across Spatial And Developmental Scales, Stephen M. Via

Theses and Dissertations

Explosive compounds are broadly distributed across the globe as a result of nearly two centuries of munitions use in warfare and military activities. Two explosive compounds have seen disproportionate use; RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and TNT (2-methyl- 1,3,5-trinitrobenzene), being the most commonly found explosives in the environment. The effects of explosives on biota have been studied in great detail; however, there is a general lack of understanding with regard to broader ecological impacts of these contaminants. My dissertation objective was to follow the impacts of explosive compounds on vegetation across scales. Impacts on vegetation at the species scale alter community composition via …

Host Densities And Parasitism Rates In A Forest Defoliator Across A Rural-Urban Landscape, Abigail J. Nelson

Theses and Dissertations

Fall cankerworm (FCW) outbreaks have recently increased in frequency and intensity in the mid-Atlantic region of the United States, especially around cities of Charlotte, NC and Richmond, VA. This study evaluated the effects of two landscape features associated with urbanization, impervious surface and forest cover, on population patterns of FCW and its parasitoids across eastern Virginia. Forest cover was positively related to parasitism rates while impervious surface was positively related to FCW abundance, suggesting that FCW outbreaks may be amplified in urban areas. FCW abundance declined over the two-year period of this study, but parasitism rate increased at most sites. …

Interactomics-Based Functional Analysis: Using Interaction Conservation To Probe Bacterial Protein Functions, J. Harry Caufield

Theses and Dissertations

The emergence of genomics as a discrete field of biology has changed humanity’s understanding of our relationship with bacteria. Sequencing the genome of each newly-discovered bacterial species can reveal novel gene sequences, though the genome may contain genes coding for hundreds or thousands of proteins of unknown function (PUFs). In some cases, these coding sequences appear to be conserved across nearly all bacteria. Exploring the functional roles of these cases ideally requires an integrative, cross-species approach involving not only gene sequences but knowledge of interactions among their products. Protein interactions, studied at genome scale, extend genomics into the field of …

System Genetic Analysis Of Mechanisms Underlying Excessive Alcohol Consumption, Maren L. Smith

Theses and Dissertations

Increased alcohol consumption over time is one of the characteristic symptoms of Alcohol Use Disorder (AUD). The molecular mechanisms underlying this escalation in intake is still the subject of study. However, the mesocortical and mesolimbic dopamine pathways, and the extended amygdala, because of their involvement in reward and reinforcement are believed to play key roles in these behavioral changes. Multiple gene expression studies have shown that alcohol affects the expression of thousands of genes in the brain. The studies discussed in this document use the systems biology technique of co-expression network analysis to attempt to find

patterns within genome-wide expression …

Genomic Comparisons And Genome Architecture Of Divergent Trypanosoma Species, Katie Bradwell

Theses and Dissertations

Virulent Trypanosoma cruzi, and the non-pathogenic Trypanosoma conorhini and Trypanosoma rangeli are protozoan parasites with divergent lifestyles. T. cruzi and T. rangeli are endemic to Latin America, whereas T. conorhini is tropicopolitan. Reduviid bug vectors spread these parasites to mammalian hosts, within which T. rangeli and T. conorhini replicate extracellularly, while T. cruzi has intracellular stages. Firstly, this work compares the genomes of these parasites to understand their differing phenotypes. Secondly, genome architecture of T. cruzi is examined to address the effect of a complex hybridization history, polycistronic transcription, and genome plasticity on this organism, and study its highly …

The Role Of E-Cadherin Force In The Maintenance Of Homeostasis In Epithelial Acini, Fnu Vani Narayanan

Theses and Dissertations

Numerous three-dimensional model systems have emerged for emulating the biochemical and physiological states of native tissue. Yet little is known about the effects of mechanical forces on cell behavior in the context of an organized tissue structure in three-dimensional cell-culture. Epithelial cells cultured in a three-dimensional environment comprised of extracellular matrix proteins form spheroids of polarized cells. Cellular responses to mechanical cues, generated from dynamic interactions with the extracellular matrix and neighboring cells, are known to influence cellular behavior to a great extent. Previous studies have shown that tumorigenic progression has been frequently linked to the down regulation of E-cadherin, …

Resolution Of Inflammation Rescues Axon Initial Segment Disruption, Nicholas M. George

Theses and Dissertations

Axonal domains are required for proper neuron function. These domains are unstable and degenerate concurrent with the inflammation in multiple sclerosis (MS) and the inflammatory disease models experimental autoimmune encephalomyelitis (EAE) and lipopolysaccharide (LPS) induced inflammation. Previous studies from our laboratory have shown that the axon initial segment (AIS) is maintained independently of the presence of myelin, but that AIS disruption is seen in MS as well as EAE and LPS-mediated inflammation. AIS loss can be interrupted in the early stage of EAE using the anti-inflammatory drug Didox. However, the potential for Didox directed repair of the AIS in later …

Influence Of Historic Landscapes And Contemporary Species Management On Chesapeake Bay Bald Eagles And Osprey, Catherine B. Viverette

Theses and Dissertations

Influence of historic landscapes and contemporary species management on Chesapeake Bay Bald Eagles and Osprey

Catherine B. Viverette

Co-distributed species with well documented demographic histories can provide good models for testing alternative hypotheses about the impact of evolutionary history, contemporary landscapes, and species management on current distribution and population structure. The Osprey (Pandion haliaetus) and Bald Eagle (Haliaeetus leucocephalus) have been extensively studied, managed and monitored across their North American breeding range, particularly in the Chesapeake Bay. We used a combination of ecological niche modelling, diet reconstruction, and population genetic modeling to understand the role of …

Examining Genetic And Environmental Influences On Alcohol Use And Externalizing Behaviors In African American Adolescents, Neeru Goyal

Theses and Dissertations

The aim of this thesis is to expand our understanding of the etiology of alcohol misuse and related disorders in African Americans using genetically informative study designs. Specifically, we take advantage of the candidate-gene approach and polygenic score analysis to extend the literature specific to African American populations. Chapter 2 explores gene x environment (GxE) interactions through the candidate gene approach to explore the relationship between two genes chosen on their potential relevance to stress response and adolescent alcohol use and misuse, among African American youth living in highly impoverished neighborhoods, as moderated by stressful life events. Chapter 3 implements …

Seasonal Variation Of Fish And Macroinvertebrate Biomass Spectra In Southern West Virginia Streams, Andrew J. Kirk

Theses and Dissertations

The biomass size spectrum - the power-law scaling relationship between average individual size and total biomass - has often been studied in lake and marine ecosystems, but rarely in lotic systems. The objective of this study was to test for characteristic biomass spectra in small temperate streams. Seasonal fish and macroinvertebrate data, including population abundance and biomass estimates, were collected in three wadeable, southern West Virginia streams from October 2013 to May 2015. Fish abundances were estimated with 3-pass electrofishing (depletion) surveys and individuals were weighed in the field. Macroinvertebrates were collected with a Hess sampler and returned to the …

The Curiosity Of Con, Petrified Breath, And An Accident Known As Blue., Steven Randall

Theses and Dissertations

My thesis installation emerged from an interest in visualizing breath. The resulting work came to exist at the intersection between art, biology, and performance.

The unicorn tapestries were used as a generative point of departure to explore the preservation and transformation of images through time, by time, and with time. Reproductions of the six tapestries were each etched into paper and then submerged into solutions of Phenol Red dye, Ferric Ferrocyanide (also known as Prussian Blue), and various forms of sodium chloride. Exhaled breath was used to encrust these images of the tapestries into physical objects which gradually crystallized and …

Evaluating And Improving The Efficiency Of Software And Algorithms For Sequence Data Analysis, Hugh L. Eaves

Theses and Dissertations

With the ever-growing size of sequence data sets, data processing and analysis are an increasingly large portion of the time and money spent on nucleic acid sequencing projects. Correspondingly, the performance of the software and algorithms used to perform that analysis has a direct effect on the time and expense involved. Although the analytical methods are widely varied, certain types of software and algorithms are applicable to a number of areas. Targeting improvements to these common elements has the potential for wide reaching rewards. This dissertation research consisted of several projects to characterize and improve upon the efficiency of several …

Exploring Pharmacological And Behavioral Mechanisms Involved In Alcohol Dependence During Adolescence, Rabha Mousa Younis

Theses and Dissertations

Alcoholism is a serious illness that is marked by uncontrollable drinking and physical dependence to alcohol. Long-term alcoholism has been linked to many health concerns such as cirrhosis of the liver and cardiovascular disease. Alcohol is one of the most commonly used drugs among adolescent populations. Given that adolescence is a unique developmental stage during which alcohol has long-term effects on future drug-taking behavior; it is essential to understand how early exposure to alcohol during adolescence may affect the abuse liability of the drug later in life. Indeed, most alcohol users start during adolescence suggesting that exposure to alcohol during …

Dynamic Regulation Of Mitochondrial Stat3 And Its Association With Cypd, Jeremy A. Meier

Theses and Dissertations

In recent years, a number of nuclear transcription factors have been shown to be present in the mitochondria where they have distinct roles in regulating mitochondrial function. Signal Transducer and Activator of Transcription 3 (STAT3), classically activated by the JAK family of receptor associated tyrosine kinases to drive nuclear gene expression, is one such transcription factor with a unique mitochondrial role. There, it has been shown to support oxidative phosphorylation, regulate mitochondrial-encoded transcripts, and be key for the transformation and growth of a number of different cancers. Despite its well-characterized functional importance at the level of the mitochondria, the mechanism …

Adducins Are Negative Regulators Of Migration And Invasion Of Normal Lung Epithelial Cells And Lung Cancer Cells, Parth Hitenbhai Amin, Parth Amin

Theses and Dissertations

Cell migration is an important component of many physiological and pathological processes such as tissue and organ morphogenesis during development, wound healing, inflammatory immune response, and tumor metastasis. The actin cytoskeleton is the basic engine driving cell migration. In the present study, we elucidate the role of an important actin interacting proteins, Adducins, in motility of normal lung epithelium and lung cancer cells. Adducins are the family of cytoskeleton protein capping the fast growing end and facilitating the bundling of actin filaments. Adducins are encoded by the three closely related genes namely alpha (ADD1), beta (ADD2) and gamma (ADD3) Adducin. …