Immunology and Infectious Disease Commons^™

Changing Antimalarial Drug Sensitivities In Uganda, Stephanie Alexis Rasmussen

Dissertations, Masters Theses, Capstones, and Culminating Projects

Dihydroartemisinin-piperaquine (DP) has demonstrated excellent efficacy for the treatment and prevention of malaria in Uganda. However, resistance to both components of this regimen has emerged in Southeast Asia. The efficacy of artemether-lumefantrine, the first-line regimen to treat malaria in Uganda, has also been excellent, but continued pressure may select for parasites with decreased sensitivity to lumefantrine. To gain insight into current drug sensitivity patterns, ex vivo sensitivities were assessed and genotypes previously associated with altered drug sensitivity were characterized for 58 isolates collected in Tororo, Uganda from subjects presenting in 2016 with malaria from the community or as part of …

A Molecular Diagnostic Survey Of Pathogens And Parasites Of Honey Bees, Apis Mellifera L., From Arkansas And Oklahoma, Dylan Cleary

Graduate Theses and Dissertations

The health and viability of colonies of the honey bee, Apis mellifera, in the United States have fluctuated dramatically over the past decade. This poses a substantial threat to agricultural production in this country. Currently, no single factor has been identified for this decline. Rather, it has been suggested that the interaction between multiple biotic and abiotic stressors may be responsible. Among these factors are pesticides, habitat loss, climate and weather, parasites and pathogens, and colony management techniques. For this reason, it is important to examine the prevalence of honey bee parasite and pathogen infection at the state level in …

The Biochemical Assessment Of Two Secreted Acid Phosphatases From Leishmania Tarentolae, Their Response To Electric Fields, Glycosidase Incubation, And / Or Vanadium, Benjamin M. Dorsey

Theses and Dissertations

Leishmaniasis, as defined by the Center for Disease Control and Prevention, is a neglected tropical disease with 1.6 million new cases reported each year. However, there is yet to be safe, effective, and affordable treatments provided to those affected by this disease1. Still underappreciated as a potential pharmaceutical targets, especially for cutaneous leishmaniasis infections, are the two isozymes of secreted acid phosphatase (SAP); secreted acid phosphatase 1 (SAP1) and secreted acid phosphatase 2 (SAP2). These enzymes are involved in the survival of the parasite in the sand fly vector, and the prevention of host macrophages from forming parasitophorous vacuole and …

Synthesis, In Vitro Characterization And Applications Of Novel 8-Aminoquinoline Fluorescent Probes, Adonis Mcqueen

USF Tampa Graduate Theses and Dissertations

Malaria is a parasitic disease that is caused by the plasmodium parasite. Plasmodium infection has affected man for thousands of years. With advances in drug discovery over the past century, malaria has evolved to possess resistance to most mainline therapeutics. This war of drug discovery vs plasmodium evolution continues to be fought to this very day, with attempts to eradicate malaria worldwide. Frontline treatments such as chloroquine, artemisinin, and atovaquone/proguanil have all seen parasitic resistance in strains of P. vivax as well as P. falciparum. While plasmodium possesses resistance to most classes of anti-malarials, the 8-aminoquinoline (8-AQ) class has …

Trypanosome Lytic Factor Mediated Immunity Against Leishmania Sp., Jyoti Pant

Dissertations, Theses, and Capstone Projects

Trypanosome Lytic Factor (TLF) is an innate immunity complex that was originally discovered to protect against African Trypanosomes. The major components of TLF are Apolipoprotein A1 (APOA1), Apolipoprotein L1 (APOL1) and HPR (Haptoglobin Related Protein), where APOL1 is necessary and sufficient for trypanolysis. Recently we have shown that TLF ameliorates infections by cutaneous Leishmania species. Here we investigated the effect of different primate and human TLF against different Leishmania sp. Our result shows that TLF kills metacyclic promastigotes of cutaneous Leishmania sp. within immune cells such as neutrophils and macrophages by two different mechanism. Using transiently transfected and germline transgenic …

Antiviral Nucleoside Inhibitors Of Leishmania Rna Virus 1: Discovery And Mechanism, John Isaac Robinson

Arts & Sciences Electronic Theses and Dissertations

Some Leishmania parasites in the Viannia sub-genus are persistently infected with Leishmania RNA virus 1 (LRV1), a single-segmented double-stranded RNA virus belonging to the family Totiviridae. Infected parasites cause greater pathology and reach higher populations in mouse models of Leishmania infection. In human disease, LRV1+ parasites are correlated with increased frequency of treatment failure and relapse. Efficient methods to detect LRV1 and eliminate it from parasites are required to better understand the role of LRV1 in Leishmania infection. We optimized multiple techniques to measure LRV1 levels in parasites, most notably using flow cytometry to measure the amount of viral capsid …

Robust Odorant Recognition In Biological And Artificial Olfaction, Nalin Katta

McKelvey School of Engineering Theses & Dissertations

Accurate detection and identification of gases pose a number of challenges for chemical sensory systems. The stimulus space is enormous; volatile compounds vary in size, charge, functional groups, and isomerization among others. Furthermore, variability arises from intrinsic (poisoning of the sensors or degradation due to aging) and extrinsic (environmental: humidity, temperature, flow patterns) sources. Nonetheless, biological olfactory systems have been refined over time to overcome these challenges. The main objective of this work is to understand how the biological olfactory system deals with these challenges, and translate them to artificial olfaction to achieve comparable capabilities. In particular, this thesis focuses …

Transmission Pattern Of Major Clonal Lineages Of Toxoplasma Gondii, Pooja Saraf

Doctoral Dissertations

Toxoplasma gondii is the most successful zoonotic pathogen known today. One-third of people are chronically infected worldwide. Different strains of T. gondii shows variability in mouse virulence which may potentially correlate with disease manifestation in humans. As a result, mouse is used as the model organism to study the virulence of T. gondii strains. To study the virulence on a global scale, it is necessary to establish a standardized approach for mice virulence assays. Thus, we review the methodologies used in different labs and put forth standardized approaches to study the T. gondii virulence in mice (Chapter 1). Recent …

Taxonomy And Systematics Of Plagioporus (Trematoda), With Descriptions Of 10 New Species From Freshwater Fishes Of The Nearctic, Thomas John Fayton

Dissertations

The Opecoelidae Ozaki, 1925 is one of the largest families of digenetic trematodes of fishes. While the family is mostly marine/estuarine, invasion of freshwater hosts has occurred at least two times. The only representative freshwater plagioporine sequenced to date is Plagiocirrus loboides Curran, Overstreet, & Tkach, 2007, which previous phylogenetic analyses resolved as being related to deep water marine opecoelids. The taxonomy of the freshwater plagioporines, particularly Plagioporus, has long been confused; homoplasy is rife within the family and has complicated the delineation of species and genera, and the freshwater species from marine forms. Here, I hypothesize that the …

The Effect Of Antigen Polymorphisms On Serological Antibody Detection Assays Based Upon The, Kristi M. Miley

USF Tampa Graduate Theses and Dissertations

Onchocerca volvulus is a filarial parasite transmitted to humans by female Simulium spp. black flies. Infection with this parasite can cause blindness and severe skin disease among humans in Africa and the Americas. Enzyme-linked Immunosorbent Assay serological testing of OV-16 antigen is a diagnostic tool for determining effective elimination of the parasite. Programs typically rely on OV–16 ELISA to evaluate the progress towards interruption and/or elimination of disease by mass drug distribution of ivermectin and vector larvicidal control efforts. As elimination grows closer, monoclonal antibody positive controls for OV-16 ELISA become important to develop for Onchocerca testing due to the …

Evolutionary Genetic Aspects Of Host Association In Generalist Ectoparasites, Benoit Talbot

Electronic Thesis and Dissertation Repository

Despite the use of the host for dispersal by most parasite species, the extremely loose relationship typical between highly mobile hosts and generalist ectoparasites may lead to very different gene flow patterns between the two, leading in turn to different spatial genetic structure, and potentially different demographic history. I examined how similar gene flow patterns are between Cimex adjunctus, a generalist ectoparasite of bats present throughout North America, and two of its key bat hosts. I first analyzed the continent-scale genetic structure and demographic history of C. adjunctus and compared it to that of two of its hosts, the …

The Role Of Rna Interference In The Control Of Leishmania Rna Virus 1 Infection, Erin Acino Brettmann

Arts & Sciences Electronic Theses and Dissertations

The presence of Leishmania RNA virus 1 (LRV1) in parasites of the Leishmania (Viannia) subgenus increases the virulence of the parasite in mouse models of leishmaniasis and is correlated with treatment failure, relapse, and the development of mucocutaneous disease in humans. LRV1 is not shed or infectious; rather, the infection is persistent, and as yet it is unknown how the parasite controls virus levels. Many eukaryotic organisms use RNA interference (RNAi) to limit virus replication, and Leishmania (Viannia) parasites have an active RNAi pathway. To determine whether Leishmania are capable of using RNAi to control LRV1, we sequenced sRNAs from …

The Role Of Histidine Rich Protein Ii In Cerebral Malaria, Priya Pal

Arts & Sciences Electronic Theses and Dissertations

Human malaria is caused by five species of Plasmodium. Of these, P. falciparum is the deadliest and is the only species that causes cerebral malaria (CM). CM is a disease of the vascular endothelium characterized by parasite sequestration, increased inflammatory cytokine production, vascular leakage and leukocyte infiltration. A distinguishing feature of P. falciparum infection is the parasite’s production and secretion of histidine-rich protein II (HRPII). HRPII accumulates to high concentrations (up to 100 µg/ml) in serum, which correlates with disease severity. Due to high serum levels of this protein, HRPII has classically been considered a biomarker for P. falciparum infection. …

Study Of Rickettsia Parkeri Colonization And Proliferation In The Tick Host Amblyomma Maculatum (Acari: Ixodidae), Khemraj Budachetri

Dissertations

Amblyomma maculatum (Gulf coast tick) ticks are prevalent across the Atlantic to Gulf Coast region of United States. These ticks are recognized vectors of Rickettsia parkeri, a spotted fever group of Rickettsia (SFGR) known to cause American boutonneuse fever associated with fever and eschar rashes localized to the site of bites. We hypothesized that Rickettsia parkeri colonization and proliferation in the tick vector involve pathogen-symbiont dynamics and tick-pathogen interactions, which influence rickettsial transmission to the victims after tick bites. The rickettsial infection is maintained across the tick life cycle for many generations due to transovarial and transstadial transmission of …

Analysis Of Antibody-Induced Plasmodium Falciparum Sporozoites Through Scanning Electron Microscopy, Sagorika Bera

USF Tampa Graduate Theses and Dissertations

Malaria is a devastating disease that continues to affect millions of people worldwide every year. Specifically, Plasmodium falciparum is the most common human malaria parasite, particularly in sub-Saharan Africa. P. falciparum causes the most malignant and debilitating symptoms with the highest mortality and complication rates. Even with the worldwide efforts of many researchers and organizations, the road to discovering a vaccine has been difficult and challenging. Due do to the improvements in in vitro liver stage assays as well as rodent models of mammalian malaria, pre-erythrocytic stages of malaria have become a more accessible target for experimental studies. These vaccine …

Development Of Tools For Stable Transfection In The Human Filarial Parasite Brugia Malayi Via The Piggybac Transposon System, Johan Chabanon

USF Tampa Graduate Theses and Dissertations

Brugia malayi is one of three species of nematode known to cause lymphatic filariasis (LF) in humans. LF infects over 120 million people, causing debilitating disease. Various global programs have been launched in the past 20 years to eliminate LF. These programs have greatly scaled up the resources and efforts allocated to halting the transmission and reducing disease burden. Only a few drugs are used to treat LF, and resistance is thus a devastating possibility. Research aimed at identifying new drug targets could therefore prove essential in elimination of LF.

Genetic manipulation of B. malayi has been limited to transient …

Novel Possibilities For The Treatment And Prevention Of Cutaneous Leishmaniasis, Eva A. Iniguez

Open Access Theses & Dissertations

Protozoan parasites from the genus Leishmania cause broad clinical manifestations known as leishmaniasis, which affect millions of people worldwide. Cutaneous leishmaniasis (CL) is mainly caused by either Leishmania major or L. tropica parasites, which produce localized cutaneous ulcers, often leading to scarring and social stigma. Currently, the disease has reached hyperendemicity levels in the Middle East due to conflict and human displacement and is one the most common forms of the disease in the Old World. Furthermore, the first choice of treatment in that region continues to be pentavalent antimonials, which are costly and highly toxic, and current vector control …

Impact Of The Parasitic Nematode Anguillicoloides Crassus On American Eels (Anguilla Rostrata) In Chesapeake Bay, Zoemma Taudel Warshafsky

Dissertations, Theses, and Masters Projects

American eels are infected by the introduced parasitic nematode, Anguillicoloides crassus, which can cause significant damage to their swimbladders. Despite the high prevalence and severe damage caused by A. crassus, the population level effects on American eels are not well understood. The prevalence and swimbladder damage in young glass eels and elvers are relatively unstudied, despite the potential for this parasite to cause tissue damage. Additionally, the effects of environmental, temporal, and spatial variables have been debated in previous studies without consensus. Also, the potential for eels to recover from infection and tissue damage has been speculated but not definitively …