Parasitology Commons^™

The 3p Framework: A Comprehensive Approach To Coping With The Emerging Infectious Disease Crisis, Orsolya Molnár, Eric Hoberg, Valeria Trivellone, Gábor Földvári, Daniel R. Brooks

MANTER: Journal of Parasite Biodiversity

The COVID-19 pandemic is the latest example of the profound socioeconomic impact of the emerging infectious disease (EID) crisis. Current health security measures are based on a failed evolutionary paradigm that presumes EID is rare and cannot be predicted because emergence requires the prior evolution of novel genetic capacities for colonizing a new host. Consequently, crisis response through preparation for previously emerged diseases and palliation following outbreaks have been the only health security options, which have become unsustainably expensive and unsuccessful. The Stockholm paradigm (SP) is an alternative evolutionary framework that suggests host changes are the result of changing conditions …

Exploring The Relationships Between South Texas Northern Bobwhite Populations And Cecal Worms Via System Dynamics, Nicole J. Traub, Benjamin L. Turner, Leonard A. Brennan, Alan M. Fedynich

National Quail Symposium Proceedings

Community ecology historically focused on plants and free-living organisms; however, problems such as defining habitat boundaries and obtaining adequate sample sizes arise when evaluating such communities. The unique nature of host-helminth systems allows parasite community ecologists to avoid these problems when testing ecological hypotheses. Unlike free-living communities that have artificially constructed boundaries, parasite communities have well-defined unambiguous boundaries within host individuals. Due to the inherently complex and dynamic nature of ecological systems, traditional experimental methods often require expensive, long-term trials beyond investigators’ time and resource budgets. Conversely, a system dynamics approach facilitates learning about such systems via simulation of ecosystem …

Investigating Host Defenses Of North American Salamanders Against The Recently Emerged Chytrid Pathogen, Batrachochytrium Salamandrivorans, Kenzie Pereira

Electronic Theses and Dissertations

A recently emerged chytrid fungal pathogen, Batrachochytrium salamandrivorans (Bsal) threatens salamander biodiversity. Bsal susceptibility varies between and within salamander species, but little is known about the mechanisms underlying these differences. Susceptibility is likely influenced by numerous interacting factors, but my dissertation studied the role of host immune responses.

My first aim investigated between species differences by studying the bioactive properties of salamander skin peptides against Bsal and the related pathogen, B. dendrobatidis (Bd). Skin peptides were collected from five salamander species, used for in vitro assays, and analyzed by RP-HPLC. While skin peptides from one …

Anticipating Infection: How Parasitism Risk Changes Animal Physiology, Patricia C. Lopes

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

1. Uninfected animals can attempt to prevent parasitism in many ways. Behavioural avoidance of parasitized conspecifics, for instance, is documented in several species.
2. Interactions with parasitized conspecifics can also, however, lead to physiological changes in uninfected animals, an effect that is much less well studied, and consequently, less well understood. The way in which exposure to parasitism risk changes the physiology of uninfected animals and the impacts of those changes on animal fitness remain a significant gap in knowledge.
3. Determining how the disease environment experienced by animals impacts their physiology, survival and reproduction has major implications for our knowledge of how …

A Checklist Of Parasites Of Peromyscus Maniculatus In North America, John Ubelaker, Gábor R. Rácz

MANTER: Journal of Parasite Biodiversity

This document represents a summary of parasites, in the broadest sense of the term, reported from Peromyscus maniculatus from throughout its range in North America. The document provides data from work ranging from paleontological findings to relatively current reports of parasites and parasitism from P. maniculatus and covers viruses, bacteria sensu lato, protists, helminths, and ectoparasites.

Perception Of Illness And Its Association With Willingness To Adhere To Treatment In Chronic Hepatitis C Patients With New Diagnosis Of Nonalcoholic Fatty Liver Disease, Carmel Kruse

The Eleanor Mann School of Nursing Student Works

Chronic liver disease is becoming the most common cause of mortality, morbidity, and utilization of healthcare services globally. Both nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis C (CHC) are frequent causes of chronic liver disease. Recently, there have been significant findings on the relationship between NAFLD and CHC; patients with CHC have a higher incidence of NAFLD. The introduction of direct-acting antivirals has cured more CHC patients than ever before. Unfortunately, the current interventions for NAFLD requiring behavioral change remain ineffective. Patient’s ability to follow advice depends largely on their health beliefs; therefore, understanding their illness perception is an …

Eluication Of Lipid Metabolic Pathways In Differentiating Giardia Lamblia Using High Resolution Mass Spectrometry, Cameron Ellis

Open Access Theses & Dissertations

Giardia lamblia is an intestinal protozoan found worldwide, including the U.S. This parasite exists in two morphologic stages - a replicative trophozoite and a relatively dormant yet viable cyst. While exposures of cysts to gastric acid during passage through the human stomach induces excystation, factors in the small intestine, where trophozoites colonize trigger encystation or cyst formation. Transformation into cyst stage is essential for Giardia to survive in the environment for months before infecting new hosts. Because of its small genome size (11.7 Mb), metabolic pathways in Giardia are highly reduced. As far as lipid metabolism is concerned, only limited …

Infection And Transmission Determinants Of Flea-Borne Rickettsioses, Hanna J. Laukaitis

<strong> Theses and Dissertations </strong>

The genus Rickettsia is comprised of Gram-negative, obligate intracellular bacteria that are spread by hematophagous arthropods. Elucidating the factors conferring rickettsial virulence has perplexed investigators for decades, complicated by the lack of efficient genetic tools necessary to uncover rickettsial- and vector-specific factors contributing to persistence. The advent of transposon mutagenesis has enabled the field to make vast developments in uncovering novel rickettsial mechanisms utilized in various host backgrounds. Thus, the aim of this study was to generate Rickettsia felis transposon mutants and characterize novel phenotypes associated with genetic disruption in an arthropod background. Distribution of rickettsiae is reliant on the …

Weaving An Interdisciplinary Microbiome Career Using Threads From Different Ecosystems, Sarah Hosler

Electronic Theses and Dissertations

Animals have trillions of microorganisms living in or on many body sites, these communities of microorganisms are called microbiomes. Microbiomes are typically host-specific, and a lot of information about the host can be determined from investigating them. Microbiome research has many real-world applications, and this thesis utilizes the One Health perspective, which acknowledges the connection of humans, animals, and environments, and emphasizes the need for collaborative, interdisciplinary research. The first interdisciplinary project is an investigation into the bacteria in wild and cultured Atlantic deep-sea scallop, Placopecten magellanicus larvae. Adults in hatcheries can be induced to spawn, but the last two …

Mitochondrial Dna Diversity, Parasite And Pathogen Occurrence, And A Potential Disease Vector In Managed And Unmanaged Honey Bee, Apis Mellifera L. Populations, Dylan Cleary

Graduate Theses and Dissertations

The western honey bee, Apis mellifera L., is a globally important pollinator plagued by several harmful stressors impacting colony health and survival. At least eight A. mellifera subspecies were imported and continue to be the genetic ancestors of U.S. honey bee populations today. Successive genetic bottle-neck events have led to reduced genetic diversity in U.S. honey bees. First, the subset of subspecies imported into the U.S. represents only a third of A. mellifera subspecies. Next, the parasitic varroa mite reduced managed and feral populations. Third, ongoing breeding practices have selected for traits from a single genetic lineage and bred from …

Functional Characterization Of The Toxoplasma Gondii Endolysosomal System, Leah Brock Thornton

All Dissertations

Toxoplasma gondii is an obligate intracellular parasite that can infect a wide range of mammalian hosts. T. gondii can cause severe disease in immunocompromised individuals as well as pregnant women, in which congenital toxoplasmosis can lead to spontaneous abortion and fetal blindness. T. gondii infects up to roughly one-third of the global human population and is the causative agent of toxoplasmosis. Given this health burden of toxoplasmosis and that antibiotics currently used for the treatment of infection lead to strong side effects, identification of parasite-specific targets are necessary for novel therapeutic strategies.

T. gondii parasites contain a dynamic and active …

The Influences Of Disperser Behavior, Host Availability, And Environmental Conditions On The Distribution Of Oak Mistletoe [Phoradendron Leucarpum (Raf.) Reveal & M. C. Johnst.] In Eastern Virginia And North Carolina, Nicholas Pearce Flanders

Biological Sciences Theses & Dissertations

Mistletoes are shrubs that typically parasitize the branches of host trees and rely on avian frugivores for seed dispersal. Because mistletoes are restricted to a narrow range of suitable recruitment sites and avian frugivores are more visible than other guilds of seed dispersers, mistletoe-frugivore systems afford opportunities for assessing the roles of dispersal limitation and local environment in determining plant distribution. These mechanisms have been proposed as determinants of the observed association of oak mistletoe [Phoradendron leucarpum (Raf.) Reveal & M. C. Johnst.] with forested wetlands in eastern Virginia and North Carolina, USA. I tested the alternative hypothesis that …

Solid-State Nmr Analysis Of Unlabeled Fungal Cell Walls From Aspergillus And Candida Species, Liyanage D. Fernando, Malitha C. Dickwella Widanage, S. Chandra Shekar, Frederic Mentink-Vigier, Ping Wang, Sungsool Wi, Tuo Wang

School of Medicine Faculty Publications

Fungal infections cause high mortality in immunocompromised individuals, which has emerged as a significant threat to human health. The efforts devoted to the development of antifungal agents targeting the cell wall polysaccharides have been hindered by our incomplete picture of the assembly and remodeling of fungal cell walls. High-resolution solid-state nuclear magnetic resonance (ss NMR) studies have substantially revised our understanding of the polymorphic structure of polysaccharides and the nanoscale organization of cell walls in Aspergillus fumigatus and multiple other fungi. However, this approach requires 13C/15N-enrichment of the sample being studied, severely restricting its application. Here we employ the dynamic …

Review Of The Cloacininae Stossich (Nemata: Strongyloidea) From Australasian Marsupials (Marsupialia: Macropodoidea), Ian Beveridge, Lesley R. Smales

MANTER: Journal of Parasite Biodiversity

The nematode sub-family Cloacininae from Australasian macropodoid marsupials is reviewed. Keys are provided to all genera and species currently known. A revised definition of the sub-family and detailed generic diagnoses are provided. For each species, full synonymies and literature citations are included along with known hosts, geographical distributions and associated DNA sequence data. A brief morphological synopsis of each species is provided together with illustrations of the morphological features needed for identification using the keys. Due to uncertainties relating to the division of the sub-family into tribes, only the nominal allocation to tribe is provided. Two new genera are erected, …

Robust Network Stability Of Mosquitoes And Human Pathogens Of Medical Importance, Donald A. Yee, Catherine Dean Bermond, Limarie J. Reyes-Torres, Nicole S. Fijman, Nicole A. Scavo, Joseph Nelsen, Susan H. Yee

Faculty Publications

Background: The exact number of mosquito species relevant to human health is unknown, posing challenges in understanding the scope and breadth of vector–pathogen relationships, and how resilient mosquito vector–pathogen networks are to targeted eradication of vectors.

Methods: We performed an extensive literature survey to determine the associations between mosquito species and their associated pathogens of human medical importance. For each vector–pathogen association, we then determined the strength of the associations (i.e., natural infection, lab infection, lab dissemination, lab transmission, known vector). A network analysis was used to identify relationships among all pathogens and vectors. Finally, we examined how …

In Sickness And In Health: Parasites Of Stranded Pacific Harbor Seals (Phoca Vitulina Richardii) In Northern Oregon And Southern Washington, Cecily Douglas Bronson

Dissertations and Theses

Parasites have the capability to infect virtually every living organism on the planet and have adapted to infiltrate every trophic level. Many species have complex indirect life cycles and rely upon hosts at different levels of the food web for growth and reproduction. In the marine environment, having a high level of parasite diversity is thought to indicate a more stable ecosystem than an environment with low parasite diversity. As one of the top predators in their environment and because of their amphibious behaviors, pinnipeds (seals and sea lions) are exposed to a wide variety of parasites, making them ideal …

Evaluating The Practical Identifiability Of A Malaria Model To Assess Conversion To Transmissible Stages, Anthony Raymond Krueger, Damie Pak, Megan Greischar, Lauren Childs

Biology and Medicine Through Mathematics Conference

No abstract provided.

Native And Non-Native Ant Impacts On Soil Microbes, Hannah A. Stewart

Biology Theses

Organisms produce chemical weapons for defense, but target organisms can develop resistance. In their introduced range, non-native species may bring “novel weapons” against which native organisms have not co-evolved resistance. The invasive European fire ant (Myrmica rubra) may have brought antimicrobial secretions to the Northeastern United States that are novel weapons against native fungal and bacterial soil organisms. I hypothesized that M. rubra would better inhibit seed pathogens resulting in greater emergence of native myrmecochorous Viola sororia seeds and, as a side effect, more strongly inhibit arbuscular mycorrhizal fungi than a native seed dispersing ant (Aphaenogaster picea …

Lipid Rafts, Exosomal Vesicles And Anti-Giardial Therapies, Brian Ivan Grajeda

Open Access Theses & Dissertations

Giardia lamblia, a protozoan parasite, is a major cause of waterborne infection, worldwide. While the trophozoite form of this parasite induces pathological symptoms in the gut, the cyst forms transmit the infection via contaminated water. Since Giardia is a non-invasive parasite, the actual mechanism by which it causes infection remains elusive. We have previously reported that Giardia assembles cholesterol and GM1 glycolipid-enriched lipid rafts (LRs) that participate in encystation and cyst production. To further delineate the role of LRs in pathogenesis, we isolated LRs from Giardia and subjected them to proteomic analysis. Various cellular proteins including the virulent proteins—e.g., giardins, …

Structural Formation And Functionality Of The Spoiie Protein In Clostridium Difficile, Rachel Siebenmorgen

Biological Sciences Undergraduate Honors Theses

My research efforts were directed toward the structure and functionality of a protein, designated SpoIIE [11], which previously has been shown to regulate C. difficile peptide utilization in addition to sporulation and toxin release. The SpoIIE protein is found in all spore-forming gram-positive bacteria and is a crucial component in activation of transcription factors and septum formation thus affecting the regulation and timing of spore development [11,12]. A truncated form of the SpoIIE protein named SpoIIE∆TM was used in an effort to determine the structure of an important but uncharacterized linker domain of the protein. If the structure and specific …