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Three Draft Genome Sequences Of Staphylococcus Species Isolated From The Urine Of Healthy Bovine Heifers (Gyr Breed), Silvia Giannattasio-Ferraz, Laura Maskeri, André P. Oliveira, Edel F. Barbosa-Stancioli, Catherine Putonti

Bioinformatics Faculty Publications

Members of the Staphylococcus genus are known pathogens causing mastitis in dairy cows, which results in major economic losses. Here, we present Staphylococcus epidermidis UFMG-H7, Staphylococcus hominis UFMG-H7B, and Staphylococcus sciuri UFMG-H6, isolated from the urine of healthy purebred Gyr heifers.

A Novel Regulator Of Thirst Behavior: Phoenixin, Christopher J. Haddock, Gislaine Almeida-Pereira, Lauren M. Stein, Gina L.C. Yosten, Willis K. Samson

Biological Sciences Faculty Research & Creative Works

A novel regulator of thirst behavior: phoenixin. Am J Physiol Regul Integr Comp Physiol 318: R1027-R1035, 2020. First published April 15, 2020; doi:10.1152/ajpregu.00023.2020.-There are examples of physiological conditions under which thirst is inappropriately exaggerated, and the mechanisms for these paradoxical ingestive behaviors remain unknown. We are interested in thirst mechanisms across the female life cycle and have identified a novel mechanism through which ingestive behavior may be activated. We discovered a previously unrecognized endogenous hypothalamic peptide, phoenixin (PNX), identified physiologically relevant actions of the peptide in brain and pituitary gland to control reproductive hormone secretion in female rodents, and in …

Species Dispersal Modes In Amphitropical Plant Species Of North And South America, Samera Lemma Mulatu

Honors College Theses

Amphitropical disjunct plants are species that occur in both North and South America but not in the intermediate equatorial region. How amphitropical species dispersed across the Americas to their current distribution remains uncertain. To explain amphitropical distributions, three hypotheses were developed to test that (1) species dispersed successively through island hopping across the tropical zone in temperate microhabitats (= stepping stones), (2) species came to their current distribution through vicariance, or (3) species dispersed by a single long distance dispersal event. Twenty-five species were studied to infer their historical distributions with species distribution models in MaxEnt. Distribution models for each …

The Effects Of Auditory Predator Cues On Foraging Patterns In Peromyscus Polionotus, Christina L. Sartain

Honors College Theses

Abstract:

While it is established that animals react to predator cues, little research has been done to assess its effect on foraging patterns and behavior. Foraging patterns are determined by a variety of factors associated with perceived predation risk, such as vegetation cover and moonlight exposure. Predator cues come in many forms, both direct and indirect, and are another indicator of perceived predation risk. Past research suggests that oldfield mice, Peromyscus polionotus, may react to indirect cues (i.e vegetation cover) more often than some direct cues, such as urine of a predator. Other indirect cues, such as vegetation cover and …

Phenotypic Analysis Of S. Aureus Strains From University Student Health Centers And Environmental Controls, Antonio Teixeira

Honors Theses

Methicillin-resistant Staphylococcus aureus (MRSA) is a group of pathogenic bacterial strains resistant to a class of antibiotics that is a major cause for concern in health care systems. There is a lack of study in whether health care centers are reservoirs for these bacteria, especially within developed countries. Five environmental swab samples were collected from five different university health care centers across the region, and 16 swab samples from a general university environment. Any isolated bacterial strains collected underwent five biochemical tests (mannitol fermentation, DNase activity, oxidase activity, catalase activity, and coagulase activity) to preliminarily identify S. aureus bacteria. 24% …

Elucidating The Effects Of Glucose Toxicity On Tauopathy And Aging, Lukas Fluitt

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Diabetes patients are at higher risk of contracting an age-related neurodegenerative disease such as Alzheimer’s disease (AD). However, the mechanisms which link these diseases are poorly understood. We hypothesize that glucose and elevated levels of the glycolysis by product advanced glycation end-products (AGEs), may be involved. AGEs accumulate with age and are elevated in both diabetic and AD patients. Diabetes is a metabolic disorder for which consumption of sugar-rich diets is a major risk factor and is central to etiology in the vast majority of cases.

We show that transgenic C. elegans expressing wild type (WT) human tau fed a …

Determining The Link Between Advanced Glycation Endproducts (Ages), Feeding, And Metabolism, Lauren Wimer

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Reactive a-dicarbonyls (a-DC’s), such as methylglyoxal (MGO), are unavoidable metabolites generated during glycolysis that accumulate with age and have been linked with chronic age-related metabolic diseases such as Diabetes Mellitus. Diabetes Mellitus is generally characterized by peripheral neuropathy and sustained hyperglycemia. Chronic hyperglycemia leads to an increase in glycolysis and a downstream increase in reactive a-DC’s. The human body has a natural method of detoxifying these a-DC’s. Glycolytic cells have enzymes which can detoxify a-DC’s, but if overwhelmed, a-DC’s can accumulate and react non-enzymatically with proteins, lipids and DNA to yield a group of molecules called advanced glycation end-products (AGEs). …

Fgf18 In Postnatal Lung Development, Andrew Hagan

Arts & Sciences Graduate Student Theses and Dissertations

The lung is a respiratory organ capable of facilitating gas exchange between external atmospheric O2 and internal CO2 in the bloodstream, necessary to oxygenate tissues. Alveoli, small balloon shaped structures at the distal end of the respiratory tree, are the meeting point between air and blood where gas exchange occurs through simple diffusion. Generation of functionally mature alveoli occurs during alveologenesis, the final postnatal stage of lung development in mice. During alveologenesis the surface area of the lung increases through formation of septal ridges (septation) which are extracellular matrix rich invaginations of the nascent alveolar wall that subdivide the alveoli. …

The Enzymatic Function Of The Tir Domain: From Axon Degeneration To Innate Immunity, Kow Essuman

Arts & Sciences Graduate Student Theses and Dissertations

The Toll/Interleukin-1 Receptor (TIR) domain is an evolutionarily ancient protein domain conserved from bacteria to eukaryotes, and is an essential signaling component of innate immunity pathways. In animal innate immunity, TIR domains have primarily been described for their scaffolding function in assembling protein complexes in host defense. In plant immunity, TIR domains are key components of the intracellular Nucleotide Binding Leucine rich repeat (NLR) immune receptors that confer resistance to pathogens. These NLR receptors trigger cell death and an immune response upon activation, but their mechanism has remained elusive. In bacteria, TIR domain proteins have been suggested to function as …

Epigenetic And Signaling Pathways Regulating The Maintenance Of Cd8 T Cell Identity And Function, Daniel Verbaro

Arts & Sciences Graduate Student Theses and Dissertations

In response to infection, antigen specific CD4 and CD8 T cells rapidly divide to provide help to the immune system and promote cytotoxicity of infected cells, respectively. Through this rapid division, CD4 and CD8 T cells maintain silencing of the opposing lineage’s genes, which is essential to acutely eliminating pathogens. However, not all pathogens are acutely eliminated even when silencing is maintained, and the pathogen persists in the presence of activated CD8 T cells. CD8 T cells chronically exposed to antigen are phenotypically different than CD8 T cells acutely exposed to antigen, but CD8 T cell still exert control over …

Outstanding Questions In Flower Metabolism, Monica Borghi, Alisdair R. Fernie

Biology Faculty Publications

The great diversity of flowers, their color, odor, taste, and shape, is mostly a result of the metabolic processes that occur in this reproductive organ when the flower and its tissues develop, grow, and finally die. Some of these metabolites serve to advertise flowers to animal pollinators, other confer protection towards abiotic stresses, and a large proportion of the molecules of the central metabolic pathways have bioenergetic and signaling functions that support growth and the transition to fruits and seeds. Although recent studies have advanced our general understanding of flower metabolism, several questions still await an answer. Here, we have …

Life Of Tau: Oligomerization, Cns Extracellular Clearance And Role As Plasma Biomarker, Tirth Patel

Arts & Sciences Graduate Student Theses and Dissertations

The microtubule associated protein tau (MAPT, commonly referred to as tau) is an intrinsically disordered, highly soluble protein predominantly expressed in axons where it binds and stabilizes microtubules. Under normal physiological conditions, soluble monomeric tau is released in the extracellular space in the interstitial fluid (ISF) by neurons. Additionally it undergoes reversible phosphorylation and other extensive modifications inside the cell under the action of a host of enzymes. However in the disease process tau loses this solubility, detaches from microtubules and ultimately migrates to the somatodendritic compartment of the neuron, where it ultimately forms insoluble fibrillar aggregates known as tau …

Pathophysiology And Treatment Of Murine Globoid Cell Leukodystrophy, Yedda Li

Arts & Sciences Graduate Student Theses and Dissertations

Infantile globoid cell leukodystrophy (GLD, Krabbe disease) is a rapidly progressing, invariably fatal pediatric disorder first described in 1916. Krabbe disease is caused by a deficiency in the lysosomal enzyme, galactosylceramidase (GALC), and is characterized clinically by failure to thrive, limb stiffness, seizures, developmental regression, and death by 2-4 years of age. Galactosylceramidase degrades the cytotoxic glycolipid, galactosylsphingosine (psychosine). In the absence of GALC activity, psychosine accumulates primarily in oligodendrocytes and Schwann cells, resulting in profound demyelination. In 1972, psychosine was hypothesized to be responsible for the clinical signs associated with Krabbe disease. However, the ‘Psychosine Hypothesis’ has never been …

Molecular Insights Into Microbial Adhesion, Roger Davies Klein

Arts & Sciences Graduate Student Theses and Dissertations

Antibiotic-resistant bacterial infections are a serious and immediate threat to global public health. In the United States alone, over 2 million individuals develop antibiotic-resistant infections annually, resulting in 23,000 deaths and $20 billion in excess health care costs. Virulence factors that allow bacteria to invade and persist within the host are promising targets for novel antimicrobial agents that could be used to curb the spread of antibiotic resistance. Development of therapeutics that can selectively eliminate pathogenic bacteria while sparing the beneficial host microbiota requires a detailed molecular understanding of critical virulence factors that facilitate interactions between pathogens and their environments. …

Effects Of Toxoplasma Gondii Infection On Nk Cells And Ilc1s, Eugene Park

Arts & Sciences Graduate Student Theses and Dissertations

Natural killer cells and Type I innate lymphoid cells (ILCs) are subsets of ILCs. In C57BL/6 mice, they share expression of the surface markers NK1. 1 and NKp46, and can produce the cytokine interferon-gamma. These similarities led to the initial classification of natural killer cells and Type I ILCs together under the category of Group 1 ILCs. However, more recent studies found that natural killer cells and ILC1s develop from distinct progenitor cells and utilize transcription factor in distinct manners. Whereas ILC1s require Tbet for their development and are Eomes-independent, natural killer cells require Tbet only for terminal maturation and …

Signaling Mechanisms In Adaptive Immunity, Saravanan Raju

Arts & Sciences Graduate Student Theses and Dissertations

The adaptive immune response consists of interplay between CD4 T cells, CD8 T cells, and B cells which function in control of pathogen in the host. T cells responding via their TCR express cytokines and costimulatory molecules that support direct effector activity and also promote high-affinity antibody generation through augmenting of B cell responses. However, the molecular components that contribute T cell function to balance viral control and the potential for host damage are incompletely understood. In this work, we establish a role for the adaptor molecule CD2AP in modulation of CD4 T cell responses to chronic LCMV infection in …

Transcriptional And Epigenetic Regulation Of Cerebellar Development And Function, Naveen C. Reddy

Arts & Sciences Graduate Student Theses and Dissertations

Precise control of gene expression is essential for neural development and function. This control is regulated by the interplay of chromatin remodelers and transcription factors (TFs). To better understand these mechanisms involved in gene regulation, we pursue two questions: 1) what are the roles of the chromatin remodeler CHD7 in cerebellar development and 2) what are the roles of the MEF2 TF family in cerebellar function. CHD7 mutations are causative for CHARGE syndrome, a heterogeneous disorder affecting many organ systems, occurring in 1:10,000 newborns. Recent MRI studies have identified cerebellar hypoplasia and foliation defects in a large portion of CHARGE …

Elucidating The Effect Of Myopathy-Causing Mutations And Second-Site Suppressors On Client Processing By J-Domain Proteins, Melanie Y. Pullen

Arts & Sciences Graduate Student Theses and Dissertations

Defects in protein quality control may lead to protein misfolding and aggregation often associated with protein conformational disorders such as Alzheimerճ Disease and Limb Girdle Muscular Dystrophy, among others. Molecular chaperones protect against protein misfolding and aggregation. A chaperone of interest is the ubiquitously expressed type II Hsp40 co-chaperone DNAJB6, which assists in protein folding and disaggregation. Mutations within the DNAJB6 G/F domain have been associated with the dominantly inherited disease Limb-Girdle Muscular Dystrophy type 1D (LGMD1D), now referred to as LGMDD1. Our collaborators recently discovered novel LGMDD1-associated mutations in the J-domain of DNAJB6. In the enclosed body of work, …

Understanding Emerging Biomarkers And Lifestyle Factors In Aging And Alzheimer Disease, Stephanie Schultz

Arts & Sciences Graduate Student Theses and Dissertations

Age-related cognitive decline and pathological brain changes are a widespread and growing public health issue. Several environmental factors, including engagement in physical activity and personality, have been shown to have potential protective effects in slowing cognitive decline and preserving healthy brain aging. However, the underlying mechanisms providing exercise- or personality-induced resilience to aging and disease remains largely unknown. Importantly, there has been an emergence of several novel biomarkers to study healthy brain aging and age-related neurodegenerative diseases including in vivo assessments of tau burden and brain metabolism via positron emission tomography (PET) imaging and neurofilament light chain (NfL), a marker …

Development Of An In Vitro Culture System For Cryptosporidium Parvum, Georgia Wilke

Arts & Sciences Graduate Student Theses and Dissertations

Cryptosporidium is a genus of protozoan parasites that causes diarrheal disease in humans and other animals. There are two major species that cause disease in humans: C. parvum, which infects both humans and animals, and C. hominis, which primarily infects humans. A recent study investigating the etiologies of pediatric diarrheal illness in Africa and South Asia found that Cryptosporidium is the 2nd most prevalent cause of diarrhea in infants and may be a contributing factor to chronic malnutrition. This discovery has led to renewed interest in studying this parasite and a reexamination of the barriers to studying Cryptosporidium. The main …

Electrophysiology Of The Inner Retina In Health And Disease: Eaat5 In The Rod Bipolar Cell And Oscillatory Potentials In Diabetes, Gregory William Bligard

Arts & Sciences Graduate Student Theses and Dissertations

The inner retina is a highly tractable location for the study of neural networks in the central nervous system and improving our understanding of the inner retina is important for the treatment of a number of ophthalmic diseases. This dissertation aims to improve understanding of the inner retina in two parts: first, a basic neuroscientific project concerning normal neuronal processing in the inner retina at a cellular level, and second, a translational ophthalmologic project regarding the development in the inner retina of a common disease. In mammals, modulation of the amplitude of dim visual signals primarily occurs at axon terminals …

Genetic Interactions And Maternal Genes Modulate Congenital Heart Disease Risk, Ehiole Ogboma Akhirome

Arts & Sciences Graduate Student Theses and Dissertations

Congenital heart disease (CHD) is the most common congenital anomaly, which makes it a leading cause of infant mortality. Congenital heart defects are a cluster of distinct developmental malformations that affect the vasculature, musculature and organization of the heart, each with varying clinical severity. Although medical and surgical advances have reduced CHD mortality in newborns and children, these patients grow up and many experience serious morbidity and early mortality. The first step toward reducing this burden is to understand the causes of CHD. Surprisingly, environmental insults and de novo mutations are estimated to explain less than one-third of CHD cases. …

Lymphatic Filariasis: Host And Parasite Factors And The Pathogenesis Of Systemic Adverse Events Following Treatment, Britt Juul Andersen

Arts & Sciences Graduate Student Theses and Dissertations

Lymphatic filariasis (LF) is a neglected tropical disease caused by the nematode parasites Wuchereria bancrofti, Brugia malayi and B. timori. The primary tool used by the Global Program to Eliminate LF is mass drug administration (MDA), and some 500 million people take the medications each year. Mild to moderate adverse events (AEs) are common after LF treatment, and these pose a major challenge for the LF elimination program. To better understand the pathogenesis of AEs, we studied patients from LF treatment trials in Côte d’Ivoire and Papua New Guinea, where plasma and leucocytes were collected pre and post-treatment and subjects …

Transcription Factor-Mediated Epigenetic Regulation In The Healthy Brain And Neurological Disease, Alexander J. Cammack

Arts & Sciences Graduate Student Theses and Dissertations

Proper cellular development and function is a complex process established by elaborate gene expression networks. These networks are regulated by epigenetic processes, which alter chromatin states and coordinate the binding of transcription factors (TFs) to regulatory elements (REs), such as enhancers, across the genome to facilitate gene expression. It follows then that a major experimental effort is to profile and understand the binding patterns of TFs to REs in various cellular types and contexts. Critically however, current TF profiling techniques are limited in their abilities to profile TF occupancy in targeted cellular populations and temporal windows, hindering investigations into epigenetic …

Cognitive Recovery In The Post-Infectious Cns, Charise Joy Garber

Arts & Sciences Graduate Student Theses and Dissertations

Neuroinflammation plays a pivotal role in a variety of diseases of the CNS associated with cognitive impairment, including Alzheimerճ Disease, Parkinsonճ Disease with dementia, Multiple Sclerosis, anti-NMDA receptor encephalitis, and West Nile Virus Neuroinvasive disease (WNND). Despite strong evidence that infiltration of peripheral immune cells and activation of resident microglia and astrocytes occurs in these various diseases, very little is known about how this altered immune environment may influence normal cognitive function. Given that communication between the nervous and immune system is essential for normal cognitive function, the central motivation of my thesis work is to understand the mechanisms by …

Effects Of Agonistic Anti-Cd137 Antibody On Chikungunya Virus Infection And B Cell Responses, Jun Hong

Arts & Sciences Graduate Student Theses and Dissertations

CD137, a member of the tumor necrosis factor receptor superfamily of cell surface proteins, acts as a costimulatory receptor on T cells, natural killer cells, B cell subsets, and some dendritic cells. Agonistic anti-CD137 monoclonal antibody (MAb) therapy has been combined with other chemotherapeutic agents in human cancer trials. Based on its ability to promote tumor clearance, we hypothesized that anti-CD137 MAb might activate immune responses and resolve chronic viral infections. We evaluated anti-CD137 MAb therapy in a mouse infection model of chikungunya virus (CHIKV), an alphavirus that causes chronic polyarthritis in humans and is associated with reservoirs of CHIKV …

Conformational Basis And Small Molecule Antagonists Of E. Coli Adhesion To The Urinary Tract, Vasilios Kalas

Arts & Sciences Graduate Student Theses and Dissertations

Urinary tract infections (UTIs) are one of the most prevalent infections, afflicting 15 million women per year in the United States with annual healthcare costs exceeding $2-3 billion. Uropathogenic Escherichia coli (UPEC) are the main etiological agent of UTIs and employ numerous virulence factors for host colonization. The most common adhesive mechanism by which UPEC mediate host-pathogen interactions is the chaperone-usher pathway (CUP), which is responsible for the assembly of proteinaceous surface appendages termed pili. Generally, CUP pili function in adherence or invasion of host tissues and in biofilm formation on medical devices and body habitats. CUP pili are highly …

The Role Of Apolipoprotein E In Alzheimer Disease: From Therapy To Mechanism, Tien-Phat Vuong Huynh

Arts & Sciences Graduate Student Theses and Dissertations

Alzheimer’s disease (AD) is a neurodegenerative disorder associated with irreversible damage to the brain, which manifests in cognitive dysfunction, memory loss, and eventual death. The pathological hallmarks of AD are amyloid plaques, which are cerebral aggregates consisting of fibrils of the amyloid β-protein (Aβ), and filamentous lesions of the microtubule-associated protein tau known as neurofibrillary tangles. In the early 1990s, the apolipoprotein E (apoE) was found to co-localize with amyloid plaques. The ε4 allele of the APOE gene was sequentially identified as the strongest genetic risk factor for AD, increasing the risk by 4 – 12-fold, whereas the ε2 allele …

Estimating Furbearer Density Using Trail-Cameras At The Piedmont National Wildlife Refuge, Georgia, Patrick M. Powers 9761971

Biology Theses

Density estimation is an important indicator of the health of wildlife populations and is commonly used to establish management practices. Trail-cameras offer a unique advantage in the density estimation of elusive animals as data can be collected without the need for physical capture. The objectives of this study were to estimate and compare furbearer density between two major habitats at the Piedmont National Wildlife Refuge (PNWR) and to compare computed density values from paired cameras located at off- and on-road locations. An additional goal was to assess the usefulness of trail-cameras as a viable technique to estimate population density on …

Draft Genome Sequence Of Klebsiella Pneumoniae Umb8492, Isolated From The Female Urinary Tract, Suma Gondi, Taylor Miller-Ensminger, Adelina Voukadinova, Alan J. Wolfe, Catherine Putonti

Bioinformatics Faculty Publications

Here, we present the draft genome sequence for Klebsiella pneumoniae strain UMB8492, isolated from a urine sample from a female patient with overactive bladder (OAB) symptoms. The assembled genome has a length of 5,660,575 bp, a G+C content of 57.19%, and an N50 value of 136,315 bp.