Digital Commons Network^™

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

All Dissertations

Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …

Filth Flies As A Vector For Some Pathogenic Bacteria Transfer, Ahmet Buyukyavuz

All Dissertations

Two separate sets of experiments were conducted to determine the transfer of bacteria by flies. An Escherichia coli ampicillin-resistant strain with a fluorescent gene was used during the experiments. The first set of experiments were divided into two trials to measure the transfer of E. coli by fruit flies to apple slices and bologna during short term exposure. Short time exposure (1, 5 and 15 min) of flies to inoculated apple slices were tested in the first trial to determine the transfer of E. coli to flies. No difference (P>0.05) in the number of bacteria transferred to flies were …

Sex Differences In Host Resistance And Tolerance To The Common Avian Pathogen Mycoplasma Gallisepticum, Chloe Connelly

Biological Sciences Undergraduate Honors Theses

As we face the threat of global pandemics, one thing becomes clear: biological research is not just about the pursuit of the unknown, but about protecting our future. Understanding disease transmission and predicting pathogen epidemics is more important than ever. Prior studies have indicated that in populations where one sex engages in more social behaviors and movement that sex may drive disease transmission. This supports sex as a factor to consider in the study of epidemic dynamics. Host physiology and immune strategies are another factor that can influence epidemics. Two commonly examined strategies are tolerance and resistance. Tolerance is the …

Past And Present Patterns Of Neutral And Adaptive Genetic Diversity In Wild Mandrills (Mandrillus Sphinx), Anna Weber

LSU New Orleans Theses and Dissertations

Although primates have fascinated researchers and the public alike for generations, one species that has remained enigmatic is the mandrill (Mandrillus sphinx), a large Cercopithecine monkey endemic to Central Africa. Mandrills are currently in decline due to bushmeat hunting, urbanization, and habitat loss. Neutral and adaptive genetic diversity are important tools for understanding evolutionary history and future viability, since diversity influences a species’ ability to adapt to a changing environment. However, thus far, minimal genetic information has been available for wild mandrills. Because of the dense vegetation in their tropical forest habitat, studying wild mandrills has proven to …

Glycolytic Inhibitors As Leads For Drug Discovery In The Pathogenic Free-Living Amoebae, Jillian Milanes

All Dissertations

The free-living amoeba, Naegleria fowleri, can cause a rare yet usually lethal infection of the brain called primary amebic meningoencephalitis. Because of poor diagnostics and limited treatment options, the mortality rate associated with the disease is >97%. Due to our finding that glucose is critical for trophozoite growth in culture, we have been interested in exploiting amoebae glucose metabolism to identify new potential drug targets. We have characterized the first enzyme of the glycolytic pathway, glucokinase (Glck), from N. fowleri and two other pathogenic free-living amoeba, Acanthamoeba castellanii and Balamuthia mandrillaris. We have assessed their biochemical properties and …

Development Of A Novel Environmental Dna (Edna) Tool For Monitoring Vulnerable Freckled Guitarfish, Pseudobatos Lentiginosus, In The Western Central Atlantic, Sarah Toepfer

Honors Theses

Rhino-rays are the most threatened group of elasmobranchs, having experienced widespread declines due to mortalities in fisheries and habitat degradation. Within the Western Central Atlantic, there are two extant species of Rhino-rays, the Critically Endangered Smalltooth Sawfish, Pristis pectinata, and the Vulnerable Freckled Guitarfish, Pseudobatos lentiginosus. Although there is research committed to P. pectinata in this region, less is known about the distribution status of P. lentiginosus. Over the past 50 years, P. lentiginosus have undergone a presumed range contraction in U.S. waters; once found from North Carolina to Texas, and historically common in the north central …

Cyclic-Di-Gmp Regulates Salmonella Typhimurium Infection Of Epithelial Cells And Macrophages, Abdulafiz Musa

Electronic Theses and Dissertations

Regulation of the bacterial second messenger cyclic-di-GMP in Salmonella Typhimurium allows it to delicately alter phenotypes to optimize invasion and survive intracellularly in epithelial cells and macrophages to become virulent and cause infection. Cyclic-di-GMP concentration is regulated by the presence of external stimuli, sensory diguanylate cyclases (DGCs) and phosphodiesterases (PDEs), and cyclic-di-GMP binding effectors. Previous studies established that maintenance of low cyclic-di-GMP concentrations is required for survival in macrophages, and that deletion of 3 active PDEs reduces this survival. Here I showed that these 3 PDEs also influenced the infection of epithelial cells. Further studies re-established the decreased survival in …

Comparative Characteristics Of Integrin Αdβ2 Binding To Native Fibrinogen And Fibrinogen Modified By Dha Oxidation During Inflammation, Ajibola Ilesanmi

Electronic Theses and Dissertations

2-ω-carboxyethylpyrrole (CEP) is a product of docosahexaenoic acid (DHA) oxidation, which forms covalent adducts with different proteins. CEP-modified proteins can interact with macrophage receptor, integrin αDβ2. This study aims to compare αDβ2 binding to its physiological ligand, fibrinogen, and CEP-modified fibrinogen, which is formed during inflammation. We hypothesize that modification of fibrinogen changes its ligand-binding properties to integrin αDβ2 which can affect macrophage migration and retention. Recombinant αD I-domain and αDβ2-transfected HEK293 cells were used for the experiments. Using biolayer interferometry, we found that the affinity of αD I-domain binding to fibrinogen-CEP was higher than fibrinogen and inhibited by the …

The Emerging Oral Pathogen, Filifactor Alocis, Modulates Antimicrobial Responses In Primed Human Neutrophils., Ian J. Snider

College of Arts & Sciences Senior Theses

Periodontitis is an irreversible, chronic inflammatory, infectious disease of the oral cavity that affects approximately half of all adults 30 years or older in the USA. The oral cavity is under high immune surveillance because of its constant exposure to microbes in the environment. The primary immune cell responsible for this surveillance is the neutrophil. Pathogens associated with periodontitis possess virulence factors and have evolved strategies to evade neutrophil antimicrobial responses to survive. One such pathogen is Filifactor alocis, whose presence is associated with the progression of periodontitis. F. alocis manipulates several neutrophil antimicrobial functional responses to avoid killing, an …

Disinfectant Efficacy Against Sars-Cov-2 Surrogates, Bovine Coronavirus And Human Coronavirus Oc43, On Hard And Soft Non-Porous Surfaces, Breanna Kimbrell

All Theses

The novel human coronavirus (HCoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged from Wuhan, China in the latter part of 2019. The rapid spread of SARS-CoV-2 amid the most recent COVID-19 pandemic forced countless foodservice establishments (FSEs) across the United States to close, taking a tremendous toll on the foodservice industry. Although primarily transmitted person-to-person, previous studies indicate that the duration of SARS-CoV-2 survival on different environmental surfaces provides adequate time for secondary transmission to occur. To prevent the further spread of SARS-CoV-2, effective disinfection of surfaces in FSEs is necessary. While disinfectants approved for use against SARS-CoV-2 are …

Effects Of Cyclic Heat Stress On The Acute Inflammatory Response In Broilers, Alessandro J. Rocchi

Poultry Science Undergraduate Honors Theses

Heat stress (HS) is a growing concern in broiler production due to increasing environmental temperatures. Little is known of the overall effect of HS on innate immunity. Lipopolysaccharide (LPS), an outer membrane component of Gram-negative bacteria, is commonly used to study the inflammatory response. In avian species, the local tissue and systemic inflammatory activities in response to LPS may be determined concurrently, over time, in an individual, using the growing feather (GF) pulp dermal test along with blood measurements (dual-window approach). To examine the effect of cyclic HS on the local and systemic acute inflammatory responses, Cobb 500 male broiler …

Nuclear And Cytoplasmic Spatial Protein Quality Control Is Coordinated By Nuclear–Vacuolar Junctions And Perinuclear Escrt, Emily M. Sontag, Fabián Morales-Polanco, Jian-Hua Chen, Gerry Mcdermott, Patrick T. Dolan, Dan Gestaut, Mark A. Le Gros, Carolyn Larabell, Judith Frydman

Biological Sciences Faculty Research and Publications

Effective protein quality control (PQC), essential for cellular health, relies on spatial sequestration of misfolded proteins into defined inclusions. Here we reveal the coordination of nuclear and cytoplasmic spatial PQC. Cytoplasmic misfolded proteins concentrate in a cytoplasmic juxtanuclear quality control compartment, while nuclear misfolded proteins sequester into an intranuclear quality control compartment (INQ). Particle tracking reveals that INQ and the juxtanuclear quality control compartment converge to face each other across the nuclear envelope at a site proximal to the nuclear–vacuolar junction marked by perinuclear ESCRT-II/III protein Chm7. Strikingly, convergence at nuclear–vacuolar junction contacts facilitates VPS4-dependent vacuolar clearance of misfolded cytoplasmic …

The Relationship Between Upper Body Muscular Power And Objectively Measured Physical Function In Healthy Older Adults, Jordan Stroope

Graduate Theses and Dissertations

The population of older adults is growing rapidly worldwide. There are significant challenges associated with an aging population, many of which are related to declining physical function. Muscular power has previously been postulated as an important physical characteristic for preserving physical function, however, much of the research has measured lower body muscular power against functional outcomes. The importance of upper body muscular power (UBMP) for physical function outcomes is less clear, thus, this study sought to examine that relationship. Forty-two older adults between the ages of 50 – 70 (avg = 60.5 years  5.7) were recruited for the current …

Evaluation Of Anaplasma Marginale Elisa Positive Cattle For Co-Infection With Ehrlichia Spp., Grayson Robbins

Animal Science Undergraduate Honors Theses

Bovine Anaplasmosis is an infectious, hemolytic disease transmitted by the rickettsia parasite Anaplasma marginale in cattle. A. marginale parasitizes the red blood cells of an animal throughout their lifetime. The beef cattle industry is the fifth largest agricultural commodity in Arkansas, so potential economic losses due to bovine anaplasmosis is a critical issue. Previously tested beef cattle herds at the University of Arkansas’ Savoy and Batesville units have tested seropositive for A. marginale with low percent inhibitions; however, all seropositive animals tested negative for infection on DNA analysis. The objective of this study was to determine the current infection status …

Osteoimmunology And The Reconstruction Of Host Immunological Status In Treponemal Infection: Effect Of Activated Immune Cells By Oral Pathogens And Treponema Pallidum On Osteoclastogenesis., Michayla Gatsos

College of Arts & Sciences Senior Theses

Syphilitic infection caused by bacterium Treponema pallidum pallidum (Tp) offers an excellent model to study the long-lasting interplay between the immune and skeletal systems and could be used to reconstruct host immunological status. We propose that a hyper-inflammatory phenotype developed during acquired syphilis will have a systemic impact on most bone microenvironments involving inflammatory processes, such as the one developed in periodontal disease (PD). Using osteoimmunological in vitro protocols, we explore whether immune activation by Tp antigens and PD pathogens can impact osteoclastogenesis (OCG), ultimately helping to understand the bone alterations caused by systemic inflammatory processes in skeletal material. We …

Investigation The Plugging Behavior Of Virus Filters, Iman Abdulqader Saab

Graduate Theses and Dissertations

A virus filtration step is integral to the manufacturing of biopharmaceuticals to ensure viral safety. A virus filter is a single-use device that uses a size-based separation process and has a unique structure with minimal defects, so that contaminating virus particles cannot pass through the membrane pores, while therapeutic molecules can. The development of novel antibodies (Abs), including significant increases in product titers, is frequently challenged by virus filter fouling, making a better understanding of the underlying mechanisms essential. This thesis focused investigating of the effect of prefilter types, buffer type and salt content on virus filtration performance. The impact …

Effects Of Maternal Disease History On Provisioning, Brooding, And Offspring Outcomes, Sakura Roberts

Biological Sciences Undergraduate Honors Theses

Disease within a population has the ability to shape the development, evolution, and general performance of a species. Pathogen exposure to hosts can influence their physiology and behavioral patterns to further shape offspring immunity. Parental conditions experienced by offspring during early development can benefit survival and fitness (e.g. increasing provisioning rates), as well as help deter against similar diseases experienced by parents. By testing if parental behavior changes can better prepare offspring outcomes for disease exposure, such as disease severity or duration of infection, we can see the beneficial impacts it has on disease dynamics and host-pathogen processes. Incubation temperature, …

Exploring A Potential Bias In Detection Of Mesopredators By Cameras, Rylee Gibson

Biological Sciences Undergraduate Honors Theses

Mesopredators, such as the raccoon (Procyon locor), Virginia opossum (Didpelphis virginiana), and striped skunk (Mephitis mephitis) play crucial ecological roles as predators, prey, and disease vectors across much of the United States. Because of their importance and the way that populations of these mesopredators can dramatically increase due to human-subsidized resources, it is imperative that studies attempting to quantify mesopredator community composition are accurate and unbiased. However, it has recently been suggested that not all mammals trigger motion-activated wildlife game cameras at the same rate and for some species detection probability may be biased. My goals for this thesis were …

Exploring The Plausibility Of Human Ecosystem Disruption Being The Cause For Increased Viral Prevalence, Andrew Ventura

University Honors Theses

Viral diseases and their prevalence--including both the number of cases and the appearance of new viruses--has increased in the last century, and these diseases have become an increasing threat to human health and well-being. The influenza and COVID-19 pandemics served both as introductions and reminders respectively to the power these viruses have to destroy and disrupt human life. As such, it intimates a necessity to investigate possible causes for the increase in these deadly diseases. Among these plausible causes is the dilution effect hypothesis, which states that decreasing the biodiversity of an ecosystem increases a pathogen's ability to infect, both …

Potency Of Novel Anti-Toxoplasmic Compounds, Matthias Walters

Theses/Capstones/Creative Projects

Toxoplasma gondii, the causative agent of toxoplasmosis, is an intracellular apicomplexan parasite. Toxoplasmosis is often asymptomatic, though, it can be debilitating or fatal to immunocompromised individuals and fetuses, being one of the leading causes of fetal mortality and birth defects. Toxoplasmosis is treated with a synergistic combination of drugs pyrimethamine and sulfadiazine; however, these drugs are only effective against the acute stage of infection, and the pyrimethamine is relatively cytotoxic, damaging bone marrow and causing noxious side effects. Due to these limitations, a safer alternative that targets the chronic stage of infection is needed. In this study, we tested …

Investigating Novel Chemotherapeutics Against The Parasite Toxoplasma Gondii, Braydon Dreher

Theses/Capstones/Creative Projects

Toxoplasma gondii, an intracellular protozoan, is a globally prevalent parasite due to the infectivity of T. gondii with nearly 2.5 billion people affected worldwide. Toxoplasma gondii can cause toxoplasmosis, which is a disease acquired through the consumption of undercooked meat or found in the feces of felines, and often leads to profound neuropathology and potentially death. Currently, acute toxoplasmosis is treated with pyrimethamine and sulfadiazine, which is a combination of an antiprotozoal and a sulfonamide. This combination of drugs directly targets the acute stage of infection but has failed to eliminate or impact the chronic carriage of bradyzoites while …

Dengue Virus And Blood Safety: A Mini-Review Of Research Publications, Festus Mulakoli, George Gachara, Eric Ndombi, Samoel Khamadi

School of Nursing & Midwifery, East Africa

The growing demand for donated whole blood and blood products to save lives has both health benefits and health risks for blood recipients at the same time. Dengue virus, a re-emerging viral disease poses a threat to blood safety, and it has spread to over 128 countries in the world. Several studies have documented transfusion-transmitted (TT) dengue, with the first cases being reported in China in 2002 and Singapore in 2008. To understand the magnitude and broader picture of the dengue virus and blood safety, we conducted a mini-review of published literature from the Scopus database. The review focused on …

East Tennessee Spatial And Temporal Species-Specific Bat Activity Patterns, Seth Morelock

Undergraduate Honors Theses

Determining the activity among species-specific bat populations within specific habitat selections can help contribute to the conservation of Appalachian bat species. This study examines the differences in species-specific bat activity patterns between three ponds of variable sizes and a southeast-facing open field with a wooded edge. Four Song Meter SM4BAT FS bioacoustics detectors were used on a 15-acre property in Fall Branch, TN, with a wildlife acoustics detector being placed at three ponds and one field. There were three stages of data collection for this study which all took place during 2023. The first stage was during the spring (March …

Differential Electrostatic Interaction Patterns In Sars-Cov-1 And Sars-Cov-2 Variants: A Molecular Dynamics Simulation Study, Ugochi Hope Isu

Graduate Theses and Dissertations

The SARS-related coronavirus (SARS-rCoV) is a highly contagious virus that has raised significant worldwide health concerns. It caused outbreaks in 2002-2003 and more recently in 2019-2020 with SARS-CoV-2. SARS-CoV-2 is responsible for the COVID-19 pandemic, which has resulted in a significant global impact on health and the economy. The spike protein of the virus plays a critical role in its infectivity and transmission, and the receptor-binding domain (RBD) within the spike protein is of particular interest, as it is responsible for binding to the human angiotensin-converting enzyme 2 (ACE2) receptor. In this study, we used Molecular dynamics (MD) simulations to …

The Effect Of Different Types Of Plastic And Rubbers Often Found In Healthcare Facilities On The Survival Of Potentially Pathogenic Bacteria, Ashely George

Honors Theses

This study focused on the survival of different species of bacteria on different types of plastics and rubbers found in healthcare facilities. The gram-positive coccus Staphylococcus aureus and the gram negative bacillus Escherichia coli, known to have importance as potential pathogens in healthcare facilities, were tested on two types of plastic (polyurethane and Polyvinyl Chloride (PVC)) and two types of rubbers (latex and nitrile) typically found on reusable healthcare surfaces. Known quantities of bacteria were aseptically placed on disinfected plastic surfaces in triplicate, air-dried, and then incubated at room temperature for 30 minutes, 20 hours, and 40 hours. After incubation, …

Elucidating Mechanisms Involved In Host Microbial-Tumor Interactions, Vidhi Chandra

Dissertations and Theses (Open Access)

Cancer is a rising cause of mortality worldwide. Microbiota is the collection of micro-organisms that live inside our bodies and can impact the host health and disease by interacting with the immune and metabolic systems. The relationship between the microbiota and cancer is complex. Gut and intratumoral microbiota can affect cancer development and progression by influencing patient outcomes and therapy responsiveness in several cancer types. Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer surrounded by a highly immuno-suppressive tumor microenvironment (TME) which limits efficacy of most available therapies. The tumoral niche provides a privileged microenvironment for microbial colonization that can …

Shortening Of Telomeres Caused By Bacterial Lipopolysaccharides In Hiv-1 Exposed Human Oral Keratinocytes, Daphne Alcala Zúñiga

Theses and Dissertations

The Human Immunodeficiency Virus-1 (HIV-1) continues to affect many individuals around the globe. Although people with HIV (PWH) have longer life expectancies because of modern treatments, they continue to exhibit comorbidities that are signs of premature aging compared to healthy individuals. The significance of the oral microbiome during HIV-1 infection has become of interest as chronic inflammatory conditions, such as periodontitis, have shed light on the detrimental effects of chronic inflammation. HIV-1 infection can promote dysbiosis, an imbalance of the oral microbiota, which in turn promotes the growth of opportunistic microorganisms such as P. gingivalis. This overpopulation enhances pathogenicity through …

Oncolytic Virus Immunotherapy: Development And Potential For Cancer Treatment, Olivia Guinness

Honors Scholar Theses

The American Cancer Society estimates that in 2023, 1,958,310 new cancer cases and 609,820 cancer deaths will occur in the United States [16]. A promising therapeutic option that has been supported by recent clinical trials is the use of oncolytic viruses to treat malignant tumors. The mechanism of action of existing treatments, such as chemotherapy, radiotherapy, and surgery, differs from that of oncolytic virus therapy because oncolytic viruses are able to affect cancer cells with specificity, minimizing side effects. When infecting a normal, non-cancerous cell, oncolytic viruses do not replicate, leaving healthy cells unaffected. In tumor cells, oncolytic viruses will …

Letters From The Professors

Scientific Kenyon: The Neuroscience Edition

No abstract provided.

Life Stressors And Immune Aging: Protective Effects Of Cognitive Reappraisal, Rebecca G. Reed, Steven R. Presnell, Ahmad Al-Attar, Charles T. Lutz, Suzanne C. Segerstrom

Markey Cancer Center Faculty Publications

Stressful life events may accelerate aspects of immune aging, but habitual use of an adaptive emotion regulation strategy, cognitive reappraisal, may attenuate these effects. This study examined whether cognitive reappraisal moderates the associations between life stressor frequency and stressor desirability on aspects of immune aging, including late-differentiated CD8+ T and natural killer (NK) cells and inflammatory markers (IL-6, TNF-α, and CRP), both between and within people in a longitudinal sample of 149 older adults (mean age = 77.8, range: 64–92 years). Participants reported stressful life events, use of cognitive reappraisal, and provided blood semiannually for up to 5 years to …