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Emotional Response In Working Memory Of Individuals With Latent Toxoplasmosis, Antonella Quimbayo

All HCAS Student Capstones, Theses, and Dissertations

Toxoplasma gondii is a prevalent parasite that infects about 30% of the world population. House cats and other felids serve as definitive hosts and acquire Toxoplasma by consuming infected prey, which are intermediate hosts. This includes rats and avians, but also large mammals such as wolves and deer. Toxoplasma gondii is known to manipulate prey behavior to enhance its transmission. For example, infected rodents demonstrates attraction to and curiosity around cat urine. Wolves infected with Toxoplasma were 11 times more likely to disperse from their pack and start a new pack. The manipulation of intermediate host behavior observed in rodents …

Cellular And Molecular Basis Of Cd4+ T Cell Help At The Effector Phase During Immunotherapy Of Mhc-Ii Negative Tumors, Samuel Oche Ameh

Arts & Sciences Graduate Student Theses and Dissertations

Immune checkpoint therapies (ICT) have shown promise in treating solid tumors, providing cures and durable protection in some cases. However, only a subset of patients benefits from ICT, indicating a need for a deeper understanding of the requirements for successful therapy. In both mice and humans, αβ T cells are key mediators of spontaneous and ICT-induced anti-tumor responses. While the anti-tumor roles of CD8+ T cells are well-studied, the role of CD4+ T cells, particularly in ICT for MHC-II negative tumors, is less understood. New insights into how CD4+ T cells modulate CD8+ T cells during ICT may lead to …

Modern Building Structures Are A Landscape-Level Driver Of Bat–Human Exposure Risk In Kenya, Tamika Lunn, Reilly T. Jackson, Paul W. Webala, Joseph G. Ogola, Kristian M. Forbes

Biological Sciences Faculty Publications and Presentations

Identifying the locations and drivers of high-risk interfaces between humans and wildlife is crucial for managing zoonotic disease risk. We suggest that continent-wide improvements to residential housing in Africa are inadvertently creating artificial roosting habitat for synanthropic free-tailed bats (family Molossidae), and that improved buildings are a rapidly accelerating exposure interface that needs urgent research attention and investment. Along a residential gradient in rural southern Kenya, we mapped building use by free-tailed bats in 1109 buildings. We show that bats often roost in human-occupied buildings, with almost one-in-ten buildings exhibiting evidence of bat occupation (9.2%) and one-in-13 found to contain …

Immunological Feedback Loops Generate Parasite Persistence Thresholds That Explain Variation In Infection Duration, Clayton E. Cressler, Daniel C.G. Metz, David A. Chang Van Oordt, Andrea L. Graham

School of Biological Sciences: Faculty Publications

Infection duration affects individual host fitness and between-host transmission. Whether an infection is cleared or becomes chronic depends on the complex interaction between host immune responses and parasite growth. Empirical and theoretical studies have suggested that there are critical thresholds of parasite dose that can determine clearance versus chronicity, driven by the ability of the parasite to manipulate host immunity. However, the mammalian immune response is characterized by strong positive and negative feedback loops that could generate duration thresholds even in the absence of direct immunomodulation. Here, we derive and analyse a simple model for the interaction between T-cell subpopulations …

The Role Of Southern Red-Backed Voles, Myodes Gapperi, And Peromyscus Mice In The Enzootic Maintenance Of Lyme Disease Spirochetes In North Dakota, Usa, Michael W. Dougherty, Nathan M. Russart, Robert A. Gaultney, Emily Marie Gisi, Haley M. Cooper, Lindsey R. Kallis, Catherine A. Brissette, Jefferson A. Vaughan

Biology Faculty Publications

Lyme disease has expanded into the Great Plains of the USA. To investigate local enzootic transmission, small mammals were trapped in two forested tracts in northeastern North Dakota during 2012 and 2013. Peromyscus mice and southern red-backed voles, Myodes gapperi, comprised over 90% of all mammals captured. One site was dominated by Peromyscus (79% of 100 mammals captured). At the other site, M. gapperi (59% of 107 mammals captured) was more abundant than Peromyscus (36%). Immature stages of two tick species parasitized small mammals: Dermacentor variabilis and Ixodes scapularis. Larval I. scapularis ectoparasitism was significantly higher on Peromyscus (81% …

Characterizing Oxylipins In Human Milk Extracellular Vesicles, Priscila Herrera

Food Science (MS) Theses

Extracellular vesicles (EVs) are non-replicating lipid bilayer membrane-bound particle formed by a parent cell and secreted into the extracellular environment. EVs in human milk are bioavailable and influence physiologic pathways that may contribute to newborn growth and development. There is interest in the oxylipin content of EVs that may contribute to the bioavailability of EVs. This research aims to characterize the oxylipin content of human milk EVs. Centrifugation and precipitation were used to isolate EVs from human milk (n = 20). The Folch method was used to extract lipids, and liquid chromatography-mass spectrometry (LC– MS) was used to qualify and …

Manipulation Of Cellular Proliferating Cell Nuclear Antigen (Pcna) During Herpes Simplex Virus Type 1 Infection, Jessica Packard, Jill A. Dembowski

Electronic Theses and Dissertations

Herpes simplex virus type 1 (HSV-1) is a double stranded DNA virus that replicates within the nucleus of host cells. Using accelerated native isolation of proteins on nascent DNA (aniPOND), cellular proteins were found to associate with HSV-1 replication forks. One host factor of interest is proliferating cell nuclear antigen (PCNA), the DNA sliding clamp that tethers DNA polymerases and DNA damage response proteins to replicating cellular DNA. Although HSV-1 encodes its own DNA polymerase processivity factor (UL42), PCNA plays a key role in HSV-1 infection. We used commercially available PCNA inhibitors and short hairpin RNAs (shRNA) to investigate how …

Partial Immunity To Mycoplasma Gallisepticum After An Initial Infection Is Long-Lasting And Reduces Transmission In Flocks Of Canaries, Madeline Sudnick

Graduate Theses and Dissertations

Pathology during a second infection can be influenced by immunity and an increase in resistance or tolerance of individuals. Population-level differences in the ability to maintain immunity can lead to contrasting survival outcomes between groups and determine how future outbreaks will spread. However, long term wildlife disease surveillance can be challenging due to lack of infrastructure and host-pathogen specific tests. Calculating disease transmission likelihood requires understanding individual-level heterogeneity in pathology and behavior, and there is limited knowledge in understanding how populations in different stages of an epidemic will transmit disease. In Chapter I, we aim to help fill a gap …

Linking Physiology, Epidemiology, And Demography: Understanding How Lianas Outcompete Trees In A Changing World, Hannes De Deurwaerder, Matteo Detto, Marco Visser, Stefan A. Schnitzer, Stephen W. Pacala

Biological Sciences Faculty Research and Publications

Extending and safeguarding tropical forest ecosystems is critical for combating climate change and biodiversity loss. One of its constituents, lianas, is spreading and increasing in abundance on a global scale. This is particularly concerning as lianas negatively impact forests’ carbon fluxes, dynamics, and overall resilience, potentially exacerbating both crises. While possibly linked to climate-change-induced atmospheric CO₂ elevation and drought intensification, the reasons behind their increasing abundance remain elusive. Prior research shows distinct physiological differences between lianas and trees, but it is unclear whether these differences confer a demographic advantage to lianas with climate change. Guided by extensive datasets collected …

Analysis Of Malarial Impact: Understanding Disease Transmission, Epidemiology, And Effects On Fetal Life, Josey Sumpter

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Malaria is a significant public health problem which mainly affects malaria endemic regions, such as parts of Africa, South America, and Western Asia. However, all hot and humid environments are susceptible to spread leading to a global scale. Malaria affects an estimated 200 million people each year, with about 600,000 cases resulting in death. Malaria is passed through the bites of infected female anopheles mosquitos, with one of the six Plasmodium genus parasites that are malarial causing. Once the parasite enters the blood stream it infects erythrocytes which can then spread throughout the entire body. Disease is often characterized by …

The Role Of An Ultraconserved Long Non-Coding Rna In B-Cell Lymphomagenesis, Swati Mohapatra

Dissertations and Theses (Open Access)

Ultraconserved regions (UCRs) are genomic segments with perfect (100%) conservation between the orthologous regions of human, rat, and mouse genomes. UCRs can be transcribed into mono-exonic long non-coding RNAs (lncRNAs) known as transcribed ultraconserved regions (T-UCRs). These regions, despite lacking protein-coding potential, are increasingly recognized for their regulatory roles in gene expression, including the modulation of non-coding RNA (ncRNA) transcripts. NcRNAs play crucial roles in cellular processes, including oncogenic transformation, with emerging evidence revealing their ability to encode small peptides known as ncRNA-encoded peptides (ncPEPs). These peptides, originating from small open reading frames (smORFs), contribute to diverse cellular functions and …

Outcomes Of Different Steroid Dosing Regimens In Critical Covid-19 Pneumonia At A Kenyan Hospital: A Retrospective Cohort Study, John Odhiambo, Jasmit Shah, Nancy Kunyiha, Felix Riunga, Charles Makasa

Internal Medicine, East Africa

Background: Among therapeutic options for severe and critical COVID- 19 infection, dexamethasone six milligrams once daily for ten days has demonstrated mortality benefit and is guideline recommended at this dose. In practice, variable doses of steroids have been used, especially in critical care settings. Our study aimed to determine the pattern of steroid dosing and outcomes in terms of critical care mortality, occurrence of dysglycaemias, and occurrence of superadded infections in patients with critical COVID-19.

Methods: A retrospective cohort study was carried out on all eligible patients admitted to the Aga Khan University Hospital, Nairobi, with critical COVID-19 between 1st …

Bat Humoral Immunity And Its Role In Viral Pathogenesis, Transmission, And Zoonosis, Anne A. Roffler, Daniel P. Maurer, Tamika J. Lunn, Tarja Sironen, Kristian M. Forbes, Aaron G. Schmidt

Biological Sciences Faculty Publications and Presentations

Bats harbor viruses that can cause severe disease and death in humans including filoviruses (e.g., Ebola virus), henipaviruses (e.g., Hendra virus), and coronaviruses (e.g., SARS-CoV). Bats often tolerate these viruses without noticeable adverse immunological effects or succumbing to disease. Previous studies have largely focused on the role of the bat’s innate immune response to control viral pathogenesis, but little is known about bat adaptive immunity. A key component of adaptive immunity is the humoral response, comprised of antibodies that can specifically recognize viral antigens with high affinity. The antibody genes within the 1,400 known bat species are highly diverse, and …

Risk Of Invasive Waterfowl Interaction With Poultry Production: Understanding Potential For Avian Pathogen Transmission Via Species Distribution Models, Reilly T. Jackson, Percival Matzinger Marshall, Chris R. Burkhart, Julia Schneck, Grant Kelly, Caleb P. Roberts

Biological Sciences Faculty Publications and Presentations

Recent outbreaks of highly pathogenic avian influenza have devastated poultry production across the United States, with more than 77 million birds culled in 2022–2024 alone. Wild waterfowl, including various invasive species, host numerous pathogens, including highly pathogenic avian influenza virus (HPAIV), and have been implicated as catalysts of disease outbreaks among native fauna and domestic birds. In major poultry-producing states like Arkansas, USA, where the poultry sector is responsible for significant economic activity (>$4 billion USD in 2022), understanding the risk of invasive waterfowl interactions with domestic poultry is critical. Here, we assessed the risk of invasive waterfowl-poultry interaction …

Host-Microbiome Interactions In The Teleost Brain, Amir Mani Varnoosfaderani

Biology ETDs

This dissertation investigates host-microbial interactions within the teleost brain, previously considered sterile. Reviewing current literature highlights significant gaps in understanding teleost brain immunity, despite prevalent neurotropic diseases. We mapped the immune profiles of rainbow trout brains and meninges, revealing the olfactory bulbs as the immune effector part of the brain and the optic tectum as a nod2 expression hub. High il6 and il10 levels were noted in the telencephalon. A persistent bacterial community within healthy salmonid brains shares diversity with gut and blood microbiota. Brain bacterial isolates exhibit genomic signatures for brain colonization and polyamine biosynthesis. The microbiota shifts across …

Development Of A Simple And Accurate Polymerase Chain Reaction Screen For Human Papillomavirus In College Students, Emily Bishop, Owen Smith, Paul E. Richardson

Journal of the South Carolina Academy of Science

Human Papillomavirus (HPV) is, according to the CDC, the most common sexually transmitted infection (STI) with many infections developing in a person's late teens or early 20’s. HPV is a nonenveloped, relatively small, icosahedral DNA virus that infects squamous epithelial cells. This infection can happen in genital, anal, and oral cavities. 90% of these infections will self-clear in two years according to the CDC. Of the 10% of infections that do not clear in two years, they could develop into carcinomas later in life. The goal of this developmental research is to create a polymerase chain reaction (PCR) that can …

Genetic Diversity Of 1,845 Rhesus Macaques Improves Genetic Variation Interpretation And Identifies Disease Models, Jun Wang, Meng Wang, Ala Moshiri, R Alan Harris, Muthuswamy Raveendran, Tracy Nguyen, Soohyun Kim, Laura Young, Keqing Wang, Roger Wiseman, David H O'Connor, Zach Johnson, Melween Martinez, Michael J Montague, Ken Sayers, Martha Lyke, Eric Vallender, Tim Stout, Yumei Li, Sara M Thomasy, Jeffrey Rogers, Rui Chen

Faculty, Staff and Students Publications

Understanding and treating human diseases require valid animal models. Leveraging the genetic diversity in rhesus macaque populations across eight primate centers in the United States, we conduct targeted-sequencing on 1845 individuals for 374 genes linked to inherited human retinal and neurodevelopmental diseases. We identify over 47,000 single nucleotide variants, a substantial proportion of which are shared with human populations. By combining rhesus and human allele frequencies with established variant prediction methods, we develop a machine learning-based score that outperforms established methods in predicting missense variant pathogenicity. Remarkably, we find a marked number of loss-of-function variants and putative deleterious variants, which …

Elucidation Of Potential Antimicrobial Properties Of Chalcones, Caleb Howell

Theses

The rise of antibiotic-resistant bacteria is a growing concern for the medical and biological community. Increased use of antibiotics has led to increased development of bacterial tolerances. This phenomenon, driven by the principles of evolution, has been exacerbated by the improper antibiotic use of these antibiotics. Often, individuals stop taking antibiotics once symptoms subside, mistakenly believing the infection is cured. This practice allows bacteria or fungi to develop resistance.

These antibiotics have been developed from secondary metabolites. While we have many effective antibiotics we are facing new threats. Chalcones are being looked at for their potential in addressing this issue. …

Subspecialty Choices Among Medicine-Pediatrics Graduates: Results From A Four-Year National Program Director Survey, Anoop Agrawal, Daniel Wells, Michael Kisielewski, Savita Misra, Benjamin Doolittle

Faculty, Staff and Students Publications

Background and objectives Dual-trained medicine-pediatrics physicians (med-peds) play an important role in the healthcare ecosystem. Little is known about the subspecialty choices of med-peds residency graduates. This study aims to characterize the subspecialty choices of med-peds residency graduates. Methods The Medicine-Pediatrics Program Directors Association (MPPDA) administers an annual survey to the program directors of all med-peds residency programs accredited by the Accreditation Council for Graduate Medical Education (ACGME). This project represents aggregate survey data from 2020-2023. Results The number of program directors responding to the survey ranged from 80.8% (63/78) to 85.7% (66/77; mean response rate: 82.8%). About 465 of …

Isolation Of Naegleria Lustrarea N. Sp. (Excavata, Discoba, Heterolobosea) From The Feces Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Brian M. Becker, Idan Banson, James M. Walker, Anant Deshwal, Matthew W. Brown, Jeffrey D. Silberman

Biological Sciences Faculty Publications and Presentations

The salamander, Ambystoma annulatum, is considered a “species of special concern” in the state of Arkansas, USA, due to its limited geographic range, specialized habitat requirements and low population size. Although metazoan parasites have been documented in this salamander species, neither its native protists nor microbiome have yet been evaluated. This is likely due to the elusive nature and under-sampling of the animal. Here, we initiate the cataloguing of microbial associates with the identification of a new heterlobosean species, Naegleria lustrarea n. sp. (Excavata, Discoba, Heterolobosea), isolated from feces of an adult A. annulatum.

Dietary Saturated Fatty Acids Modulate Host Innate Immunity, Amy Lorraine Seufert

Dissertations and Theses

Nutrition, cellular metabolism, and inflammatory regulation of the immune system are interconnected, and advancing our understanding of this will greatly improve treatment of metabolic and inflammatory disease. Specifically, dietary saturated fats are becoming increasingly appreciated for their ability to modify innate immune cell function in mammals following absorption into the blood and lymphatic circulation systems. The work herein focuses on the capacity for lipids in the diet to modulate innate immune memory. My thesis first broadly outlines fundamental background, including: the evolution of human nutrition, the discovery of innate immune memory, and key topics that reoccur throughout the text surrounding …

Feather Mites Through Genomic And Ecological Lenses: Host Specificity And Symbiosis At Multiple Levels Of Organization, Alix Elizabeth Matthews

Student Theses and Dissertations

Symbionts, or organisms that form close and persistent associations with hosts, are ubiquitous across the tree of life, and symbioses are among the most common interspecific interactions in the natural world. Symbionts play a fundamental ecological and evolutionary role across multiple levels of biological organization – from individuals to ecosystems – and can have strong effects on global biodiversity. However, many aspects of these relationships are poorly understood including symbiont genetic diversity (inter- and intraspecific), host specificity, and the mechanisms underlying their functional nature or any context-dependent patterns. This dissertation uses a model symbiosis between permanent, obligate, ectosymbiotic vane-dwelling feather …

Current And Future Environmental Suitability For Bats Hosting Potential Zoonotic Pathogens In Rural Kenya, Ruut Uusitalo, Reilly T. Jackson, Tamika J. Lunn, Essi M. Kohonen, Joseph G. Ogala, Paul W. Wabala, Tarja A. Sironen, Kristian M. Forbes

Biological Sciences Faculty Publications and Presentations

Synanthropic bats live in close proximity to humans and domestic animals, creating opportunities for potential pathogen spillover. We explored environmental correlates of occurrence for a widely distributed synanthropic African bat, Mops pumilus—a species associated with potential zoonotic viruses—and estimated current and future environmental suitability in the Taita Hills region and surrounding plains in Taita–Taveta County in southeast Kenya. To project future environmental suitability, we used four Coupled Model Intercomparison Project Phase 6 general circulation models that capture temperature and precipitation changes for East Africa. The models were parameterized with empirical capture data of M. pumilus collected …

Neuroinflammation And Gut Barrier Function Post Traumatic Brain Injury, Anne Sullivan

Master's Theses

Traumatic Brain Injury (TBI) is a major cause of morbidity and mortality that afflicts millions of people in the United States annually. TBI mice had significantly increased expression of the pro-inflammatory cytokines and decreased expression of tight junction proteins CLDN5, CLDN12, and OCLD in brain lesion tissue. TBI mice exhibited a significant accumulation of FITC in the middle and distal part of the small intestine compared to sham mice. TBI mice exhibited an increase in pathogenic bacteria Enterobacteriaceae and a decrease in beneficial bacteria lactobacillus. TBI mice exhibited a trend toward an increase in permeability compared to no treatment. These …

The Role Of Micrornas In Lung Inflammation After Alcohol And Burn Injury, Connor O'Neal Guzior

Master's Theses

Acute lung injury (ALI) and the subsequent development of acute respiratory distress syndrome (ARDS) are among the leading causes of post-burn morbidity and mortality. MiRNAs are small non-coding RNA molecules that are known to regulate gene expression and help regulate lung homeostasis. In this study, we profiled four anti-inflammatory miRNAs (miR-146a, miR-150, miR-194, and miR-671) in lung tissue following an alcohol and burn injury. We found that miR-146a and miR-671 were significantly downregulated in lungs one day after combined injury, leading to increased lung inflammation and pathology. Biological sex did not have an effect on this pathophysiological process. We also …

Capture Rates Of Eptesicus Fuscus Increase Following White-Nose Syndrome Across The Eastern Us, Molly C. Simonis, Lynn K. Hartzler, Gregory G. Turner, Michael R. Scafini, Joseph S. Johnson, Megan A. Rúa

Biological Sciences Faculty Publications

Emerging infectious diseases threaten wildlife globally. While the effects of infectious diseases on hosts with severe infections and high mortality rates often receive considerable attention, effects on hosts that persist despite infection are less frequently studied. To understand how persisting host populations change in the face of disease, we quantified changes to the capture rates of Eptesicus fuscus (big brown bats), a persisting species susceptible to infection by the invasive fungal pathogen Pseudogymnoascus destructans (Pd; causative agent for white-nose syndrome), across the eastern US using a 30-year dataset. Capture rates of male and female E. fuscus increased from preinvasion to …

Fisheries Occasional Publication No.147 - Aquaculture Development Zones – Policy Position Relating To Permitted Alternative Species, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Occasional Publications

The purpose of this policy is to set out considerations relevant to the assessment of aquaculture proposals within Aquaculture Development Zones (ADZ) for species distinct from the group of species for which the ADZ was initially established (Alternative Species).

(R2071) Global Stability Analysis Of Chikv Dynamics Model With Adaptive Immunity And Distributed Time Delays, Taofeek O. Alade, Samson Olaniyi, Hassan A. Idris, Yaqoob Al Rahbi, Mohammad Alnegga

Applications and Applied Mathematics: An International Journal (AAM)

The application of mathematical biology and dynamical systems has proven to be an effective approach for studying viral infection models. To contribute to this research, our paper proposes a new CHIKV model that takes into account an adaptive immune response and distributed time delays, which accurately reflects the time lag between initial viral contacts and the production of new active CHIKV particles. By analyzing the model’s qualitative behavior, we establish a biological threshold number that can predict whether CHIKV will be cleared from or persist in the body. We demonstrate the global stability of both CHIKV-present and CHIKV-free steady states …

Effects Of Food Supplementation And Helminth Removal On Space Use And Spatial Overlap In Wild Rodent Populations, Janine Mistrick, Jasmin S.M. Veitch, Shannon M. Kitchen, Samuel Clague, Brent C. Newman, Richard J. Hall, Sarah A. Budischak, Kristian M. Forbes, Megan E. Craft

Biological Sciences Faculty Publications and Presentations

• Animal space use and spatial overlap can have important consequences for population-level processes such as social interactions and pathogen transmission. Identifying how environmental variability and inter-individual variation affect spatial patterns and in turn influence interactions in animal populations is a priority for the study of animal behaviour and disease ecology. Environmental food availability and macroparasite infection are common drivers of variation, but there are few experimental studies investigating how they affect spatial patterns of wildlife.
• Bank voles (Clethrionomys glareolus) are a tractable study system to investigate spatial patterns of wildlife and are amenable to experimental manipulations. We conducted …

Bacillary Angiomatosis In A Patient With Hiv And Disseminated Mycobacterium Avium Complex Infection, Ibeth P Caceres, Angelique Ruml, Rubi Montejano, Omid Jalali, Theodore Rosen

Faculty, Staff and Students Publications

Bartonella is a genus of arthropod-borne bacterial pathogens that typically cause persistent infections of erythrocytes and endothelial cells in mammalian hosts. The species that primarily infect humans are Bartonella henselae and Bartonella quintana. Depending on immune status, the clinical presentation of B. henselae may differ, manifesting as cat-scratch disease in immunocompetent individuals or bacillary angiomatosis (BA) and peliosis in immunocompromised patients. The cutaneous manifestations of BA are typically characterized by occasionally painful, angiomatous papules and nodules, often with a chronic, persistent course. Herein, we present a case of biopsy-confirmed B. henselae infection in a 32-year-old HIV-positive female with acquired immunodeficiency …