Parasitology Commons^™

A Mechanistic Study On The Immunological Effects Of A Novel Anti-Schistosomal Compound, Caleb M. Sandall, Paul H. Davis

Theses/Capstones/Creative Projects

Schistosomiasis is a condition caused by a parasitic worm infection that is one of the primary neglected tropical diseases. It infects approximately 250 million people every year, and it causes the second largest economic impact from any parasitic disease. There exists a treatment for Schistosomiasis; however, it is ineffective against the juvenile stages of the worm. A novel drug has been developed that has been illustrated to have efficacy against all stages of worm infection. However, before this drug can be utilized, its method of action must be determined. Preliminary single cell transcriptomic data from our lab suggests that our …

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, …

What Is The Prevalence Of Dirofilaria Immitis (Dog Heartworm) In Invasive Aedes Mosquitoes?, Leen Yousef, Johan Espinoza Corrales, Daniela H. Dolar, Taylor K. Trieu, Aisha Popalzai, Agamchat Dhami

Pacific Undergraduate Research and Creativity Conference (PURCC)

No abstract provided.

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. …

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 …

The Role Of Chemical Cues In Host Susceptibility To Fish-Parasitic Gnathiid Isopods., Clayton M. Vondriska

Student Theses and Dissertations

Parasitism is one of the most common lifestyle strategies. Ectoparasites must navigate complex environments to find their host and many rely heavily on chemical cues to do so. Gnathiid isopods are common parasites that use chemical cues to find their marine fish hosts. While gnathiids are considered host-generalists, hosts vary in their susceptibility to infestation. However, the mechanisms that mediate differential susceptibility are unknown. Here I used field and laboratory experiments to investigate if the chemo-attractiveness of hosts explains differences in susceptibility of Caribbean reef fishes to infestation by a common Caribbean gnathiid isopod, Gnathia marleyi. While G. marleyi can …

Maps Of Ticks (Acari: Argasidae, Ixodidae) For Austria And South Tyrol, Italy, Franz Rubel, Katharina Brugger

Harold W. Manter Laboratory of Parasitology: Library Materials

A first compilation of georeferenced tick locations in Austria and South Tyrol, Italy, is presented here. This allows the tick fauna to be examined in the various climatic regions of the European Alps. The dataset comprises 424 tick locations of Austria and 48 tick locations of South Tyrol, which were digitized from literature and visualized in the form of geographical maps. The tick fauna of Austria includes two species of Argasidae in the genera Argas and Carios and 15 species of Ixodidae in the genera Dermacentor, Haemaphysalis, and Ixodes, altogether 17 tick species. In addition, two species …

Larval Habitats, Species Composition And Distribution Of Malaria Vectors In Regions With Autochthonous And Imported Malaria In Roraima State, Brazil, Nathália Coelho Vargas De Almeida, Jaime Louzada, Maycon Sebastião Alberto Santos Neves, Thiago M. Carvalho, Júlio Castro‑Alves, Teresa Fernandes Silva‑Do‑Nascimento, Ananias A. Escalante, Joseli Oliveira‑Ferreira

Harold W. Manter Laboratory of Parasitology: Library Materials

Background: Malaria control requires local action. Assessing the vector diversity and abundance provides information on the local malariogenic potential or risk of transmission. This study aimed to determine the Anopheles species composition, habitats, seasonal occurrence, and distribution in areas with autochthonous and imported malaria cases in Roraima State.

Methods: A longitudinal study was conducted from January 2017 to October 2018, sampling larvae and adult mosquitoes in three municipalities of Roraima State: Boa Vista, Pacaraima and São João da Baliza. These areas have different risks of malaria importation. Four to six mosquito larval habitats were selected for larval sampling …

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 …

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 …

Role Of Three Bird Species In The Life Cycle Of Two Sarcocystis Spp. (Apicomplexa, Sarcocystidae) In The Czech Republic, Ondřej Máca, David González-Solís

Harold W. Manter Laboratory of Parasitology: Library Materials

Birds are one of the groups involved in the development of Sarcocystis Lankester (1882), serving either as intermediate or definitive hosts. The white-tailed sea eagle Haliaeetus albicilla (Linnaeus, 1758), red kite Milvus milvus (Linnaeus, 1758) (both Accipitriformes) and common starlings Sturnus vulgaris Linnaeus, 1758 (Passeriformes) were examined to elucidate their participation in the development of Sarcocystis, as well as to determine the specific identity of the parasites based on morphological and especially molecular analyses. In 2020–2021, one white-tailed eagle, one red kite and five common starlings were parasitologically examined for the presence of Sarcocystis using flotation centrifugation coprological method …

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

Graduate Theses/Dissertations

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 …

Novel Molecular Approaches To Diagnostic And Epidemiological Analyses Of Cryptosporidiumspp.Implicated In Clinical Infection, Jennifer K. O'Leary

Theses

Cryptosporidium remains an underestimated, yet highly prevalent, parasitic agent of gastrointestinal illness worldwide. In clinical settings, diagnosis has previously relied on microscopic techniques. However, enteric parasite targeting molecular tools, such as real-time PCR panels, have superseded microscopy in recent years. This body of work examines the nature, implications and opportunities of this paradigm shift. This thesis is divided into seven chapters that consist of a literature review chapter, five experimental chapters focusing on the molecular diagnosis and epidemiological analysis of Cryptosporidium spp., and a final summary chapter. Chapter I provides the contextual narrative and supportive reasoning behind the research undertaken …

Dissecting The Role Of Actin-Myosin Motor And Calcium – Based Organelle Secretion In Motility Of Sarcocystis Neurona, Parul Suri

Theses and Dissertations--Veterinary Science

Sarcocystis neurona is a protozoan parasite that causes a rare neurological disorder in horses called Equine Protozoal Myeloencephalitis (EPM). Apicomplexa use actin-myosin based motor and organelle secretion to interact with the host cell and invade it. Despite the importance of motility and invasion-needed factors, the mechanisms by which S. neurona employs host cell association strategies to interact remains largely undefined. To address this knowledge gap, we hypothesize that just like other Apicomplexa, S. neurona utilizes actin polymerization for substrate-dependent gliding. Moreover, we also hypothesize that micronemes of S. neurona secrete proteins that are calcium-dependent. Based on previous studies in T. …

The Microbiome Of The Equine Roundworm, Parascaris Spp., Jennifer Lynn Cain

Theses and Dissertations--Veterinary Science

Parasitic nematodes, including the large roundworms colloquially known as ascarids, affect the health and well-being of livestock animals worldwide. The equine ascarid, Parascaris spp., was the first ascarid parasite to develop wide-spread anthelmintic drug resistance, with other species slowly following suit. There are no new classes of anthelmintics currently in development, and a solution to the ever-increasing prevalence of resistance is desperately needed. The microbiome has been shown to be an important factor in the fitness and health of many organisms and changes to microbiome composition have been associated with a plethora of diseases. The microbiome is also important to …

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 …

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

Biological Sciences Faculty Publications

No abstract provided.

Tick Transmission Of Borrelia Burgdorferi To The Murine Host Is Not Influenced By Environmentally Acquired Midgut Microbiota, Sukanya Narasimhan, Nallakkandi Rajeevan, Morven Graham, Ming-Jie Wu, Kathleen Deponte, Solenne Marion, Orlanne Masson, Anya J. O'Neal, Daniel E. Sonenshine, Erol Fikrig

Biological Sciences Faculty Publications

Background

Ixodes scapularis is the predominant tick vector of Borrelia burgdorferi, the agent of Lyme disease, in the USA. Molecular interactions between the tick and B. burgdorferi orchestrate the migration of spirochetes from the midgut to the salivary glands—critical steps that precede transmission to the vertebrate host. Over the last decade, research efforts have invoked a potential role for the tick microbiome in modulating tick-pathogen interactions.

Results

Using multiple strategies to perturb the microbiome composition of B. burgdorferi-infected nymphal ticks, we observe that changes in the microbiome composition do not significantly influence B. burgdorferi migration from the midgut, invasion of …

Circling The Drain: The Extinction Crisis And The Future Of Humanity, Rodolfo Dirzo, Gerardo Ceballos, Paul R. Ehrlich

Harold W. Manter Laboratory of Parasitology: Library Materials

Humanity has triggered the sixth mass extinction episode since the beginning of the Phanerozoic. The complexity of this extinction crisis is centered on the intersection of two complex adaptive systems: human culture and ecosystem functioning, although the significance of this intersection is not properly appreciated. Human beings are part of biodiversity and elements in a global ecosystem. Civilization, and perhaps even the fate of our species, is utterly dependent on that ecosystem’s proper functioning, which society is increasingly degrading. The crisis seems rooted in three factors. First, relatively few people globally are aware of its existence. Second, most people who …