Parasitology Commons^™

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

Theses and Dissertations

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 ...

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.

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 ...

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). I also expected ...

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 ...

Understanding The Natural History Of Juvenile Amblyomma Maculatum In Southeastern Virginia, Christina Espada, Holly Gaff

College of Sciences Posters

Amblyomma maculatum, the Gulf Coast tick, is a species of increasing public health concern. Adult A. maculatum is a known vector of several pathogens including Rickettsia parkeri, the causative agent of Rickettsia parkeri rickettsiosis. Amblyomma maculatum has expanded northward from its historic range along the Gulf Coast, with populations reportedly establishing in southeastern Virginia in 2010. Recently established populations of A. maculatum tend to have higher R. parkeri infection prevalence compared to longer established populations. This pattern holds for all populations found so far in southeastern Virginia, with a prevalence of R. parkeri in about 60% of A. maculatum compared ...

Sensitivity Of A Lamp Assay For Detection Of The Dinoflagellate Amyloodinium Ocellatum In Simulated Field Conditions And Freeze Tolerance Of The Parasite, Robert Gonzales

Master's Theses

The obligate parasitic dinoflagellate Amyloodinium ocellatum causes amyloodiniosis in warm water marine fishes. The prolific parasite, which has a direct, three-stage life cycle, is highly infectious and can cause heavy losses in aquaculture. Prevention, biosecurity, and early detection are vital for control. In this work, microscopy and a loop-mediated isothermal amplification (LAMP) assay were compared for early diagnosis of A. ocellatum in cultured stocks, and the freeze tolerance of tomonts was assessed to determine if frozen wild fish used as fish food can serve as a potential vector for the parasite.

The lowest dinospore concentration that could be detected by ...

Stepping-Stones And Mediators Of Pandemic Expansion—A Context For Humans As Ecological Super-Spreaders, Eric P. Hoberg, Walter A. Boeger, Daniel R. Brooks, Valeria Trivellone, Salvatore J. Agosta

MANTER: Journal of Parasite Biodiversity

Humans represent ecological super-spreaders in the dissemination and introduction of pathogens. These processes, consistent with the dynamics of the Stockholm paradigm, are exemplified in the origin and globalized distributions of SARS-CoV-2 since initial recognition in central Asia during 2019 and 2020. SARS-like viruses are not widespread in mammals but appear widespread in chiropterans. Bats are isolated ecologically from most other assemblages of mammals in terrestrial systems. Humans may be the stepping-stone hosts for broad global dissemination and wider infection (given the opportunity) among diverse assemblages of mammals in which host and viral capacity are compatible. Human globalization mediated insertion in ...

Effects Of Experimental Malaria Infection On Migration Of Yellow-Rumped Warblers (Setophaga Coronata), Rebecca J. Howe

Electronic Thesis and Dissertation Repository

The potential of migratory animals to spread infectious diseases depends on how infection affects movement. If infection delays or slows the speed of travel, transmission to uninfected individuals may be reduced. Whether and how malaria (Plasmodium spp.) affects bird migration has received little experimental research. I captured 40 actively-migrating Yellow-rumped Warblers (Setophaga coronata) at a migration stopover site and held them in captivity. I inoculated 25 with P. cathemerium while 15 received sham inoculations. After 12 days the birds were released. Six P. cathemerium-inoculated birds (24%) developed P. cathemerium infections after inoculation. I radio-tagged all birds, and used radio ...

Comparison Of Percutaneous Vs Oral Infection Of Hamsters With The Hookworm Ancylostoma Ceylanicum: Parasite Development, Pathology And Primary Immune Response, Richard D. Bungiro, Lisa M. Harrison, Blaise Dondji, Michael Cappello

Biology Faculty Scholarship

Background

Hundreds of millions of people in poor countries continue to suffer from disease caused by bloodfeeding hookworms. While mice and rats are not reliably permissive hosts for any human hookworm species, adult Golden Syrian hamsters are fully permissive for the human and animal pathogen Ancylostoma ceylanicum. Similar to humans, hamsters may be infected with A. ceylanicum third-stage larvae orally or percutaneously. Oral infection typically leads to consistent worm yields in hamsters but may not accurately reflect the clinical and immunological manifestations of human infection resulting from skin penetration.

Methodology/Principal findings

In this study we compared host responses following ...

Thrombospondin-1 Expression And Modulation Of Wnt And Hippo Signaling Pathways During The Early Phase Of Trypanosoma Cruzi Infection Of Heart Endothelial Cells, Ashutosh Arun, Kayla J. Rayford, Ayorinde Cooley, Tanu Rana, Girish Rachakonda, Fernando Villalta, Siddharth Pratap, Maria F. Lima, Nader Sheibani, Pius N. Nde

Publications and Research

The protozoan parasite, Trypanosoma cruzi, causes severe morbidity and mortality in afflicted individuals. Approximately 30% of T. cruzi infected individuals present with cardiac pathology. The invasive forms of the parasite are carried in the vascular system to infect other cells of the body. During transportation, the molecular mechanisms by which the parasite signals and interact with host endothelial cells (EC) especially heart endothelium is currently unknown. The parasite increases host thrombospondin-1 (TSP1) expression and activates the Wnt/β-catenin and hippo signaling pathways during the early phase of infection. The links between TSP1 and activation of the signaling pathways and their ...

Editorial: Tick Saliva: Secret To Blood Feeding Success, Daniel E. Sonenshine, Patricia A. Nuttall, Sukanya Narasimhan

Biological Sciences Faculty Publications

No abstract provided.

Rickettsial Pathogen Perturbs Tick Circadian Gene To Infect The Vertebrate Host, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Ixodes scapularis is a medically important tick that transmits several microbes to humans, including rickettsial pathogen Anaplasma phagocytophilum. In nature, these ticks encounter several abiotic factors including changes in temperature, humidity, and light. Many organisms use endogenously generated circadian pathways to encounter abiotic factors. In this study, we provide evidence for the first time to show that A. phagocytophilum modulates the arthropod circadian gene for its transmission to the vertebrate host. We noted a circadian oscillation in the expression of arthropod clock, bmal1, period and timeless genes when ticks or tick cells were exposed to alternate 12 h light: 12 ...

The Comparison Of Three Different Fecal Egg Counting Techniques And Their Ability To Perform A Fecal Egg Count Reduction Test, Diana J. Summitt

MSU Graduate Theses

A comprehensive gastrointestinal parasite control program includes an understanding of common parasites, application of chemotherapeutic agents, as well as frequent and appropriate diagnostic testing. An effective control program is essential for facilities such as animal shelters, that deal with large populations of transient canines with unknown parasite exposure and deworming history. The identification of a sensitive flotation method to evaluate anthelmintic efficacy is critical in monitoring parasite populations for drug resistance. The objective of the current study was to compare three different fecal egg counting technologies and their ability to perform a fecal egg reduction test. The flotation techniques evaluated ...

Comprehensive Study Of Human Pathogenic Trypanosomatids: From Chemotherapies To Disease Ecology, Felipe Rodriguez

Open Access Theses & Dissertations

The vector-borne diseases Leishmaniasis and Chagas disease, caused by the kinetoplastid parasites Leishmania spp. and Trypanosoma cruzi respectively, are among the most important parasitic diseases in the group of neglected tropical diseases. Even though the two diseases are endemic to the Americas, they affect millions of people worldwide. Leishmaniasis and Chagas disease cause a great array of symptoms and some of them can be fatal if left undiagnosed and untreated. Current treatment regimens are becoming less effective, vaccines are still not available, and diagnosis needs to be improved. Vector control has been responsible for a decrease of diseases in endemic ...

Natterer In Neotropical Nematoda: Species Described By Rudolphi, Diesing, And Molin, Ricardo Guerrero

MANTER: Journal of Parasite Biodiversity

Between 1817 and 1835 Johann Natterer collected 1,729 samples of endoparasitic helminths in Brazil and southern Venezuela. Of the 323 names that were assigned to the collected nematode specimens, 163 are still valid and accepted species, 84 are still doubtful, and 76 must be rejected. In this work, each name is analyzed and correlated to the literature to clarify its taxonomic status.

The purpose of this review of the material collected by Natterer is to establish a complete list of all described species; their current status; and whether they are valid species, synonyms, or nomen nudum as well as ...

Diversity Of Tetrabothriidae (Eucestoda) Among Holarctic Alcidae (Charadriiformes): Resolution Of The Tetrabothrius Jagerskioeldi Cryptic Species Complex— Cestodes Of Alcinae—Provides Insights On The Dynamic Nature Of Tapeworm And Marine Bird Faunas Under The Stockholm Paradigm, Eric P. Hoberg, Kaylen Marie Soudachanh

MANTER: Journal of Parasite Biodiversity

We begin resolution of the Tetrabothrius jagerskioeldi–species complex with descriptions of Tetrabothrius alcae n. sp. based on numerous specimens, primarily in murres (species of Uria), from the greater North Pacific basin and Tetrabothrius sinistralis n. sp. based on cestodes in guillemots (species of Cepphus) from the central Bering Sea and West Greenland. These tetrabothriids are characterized, among 44 species of Tetrabothrius in avian hosts, by attributes of the scolex, male and female organ systems, structure and dimensions of the vitelline gland, numbers of testes, configuration of the genital atrium, genital papillae and the male and female atrial canals, position ...

Molecular And Cellular Characterizations Of Glucosylceramide Transferase (Synthase) In Giardia Lamblia, Vanessa Enriquez

Open Access Theses & Dissertations

Giardiasis, caused by an intestinal protozoan, Giardia lamblia, is a major public health problem worldwide. Giardia infection is spread through the fecal-oral route via contaminated water and food. It is estimated that over 280 million people are infected with Giardia across the globe. Giardia is a non-invasive parasite and consists of a two-stage life cycle: trophozoites and cysts. Ingested cysts undergo excystation in the proximal small intestine, releasing two trophozoites (excyzoites). Upon reaching the distal small intestine and colonizing there, trophozoites transform into cysts by encystation. It has been reported earlier that the process of encystation induced the synThesis of ...

In The Search For Novel Treatments For Chagas' Disease Using Cutting-Edge Imaging Technology, Karsten Dieter Amezcua Winter

Open Access Theses & Dissertations

Chagas disease (ChD) is caused by Trypanosoma cruzi (T. cruzi), an intracellular protozoan parasite. ChD has a global mortality of 15,000 annual deaths, and approximately, 8-10 million people are infected. There is growing concern in the United States as autochthonous cases of ChD have been reported in the southern region. The two available treatments are only partially effective and highly toxic. N-aroyl derivatives and α, β-unsaturated ketones have been previously tested against Leishmania, a closely related parasite, demonstrating selective toxicity towards the microorganism. The objective of this study is to evaluate a drug library consisting of 21 α, β-unsaturated ...

Parasite Infections In Poultry Environments (Case Report On Gallus Domesticus Endoparasite), Phebe Amadea Tanuwijaya, David Febraldo

Journal of Environmental Science and Sustainable Development

Infection of nematode and cestode worms in chickens can cause decreased egg production, weight loss, growth problems, weakness. The objective of this case study is to look at how an epidemiological approach, clinical symptoms, anatomical pathology investigation, and laboratory testing might help with disease diagnosis. The chicken was found from Banjar Tanggahan Tengah, Bangli, Bali with the type of native chicken (Gallus domesticus), at least 3 months old with the protocol number 369 / N / 20. Samples taken were brain, trachea, lungs, liver, heart, spleen, kidneys, proventriculus, intestines, and feces. Laboratory examinations carried out include histopathology, microbiology, and parasitology. The results ...