Life Sciences Commons^™

Evaluation Of Protection Induced By Dna Vaccine Candidate Against Leishmania Mexicana In Balb/C Mice Model, Rosina Rodarte

Open Access Theses & Dissertations

Background and Significance. The leishmaniases are a diverse group of diseases with four major clinical manifestations: cutaneous, mucocutaneous, visceral, and diffuse. Approximately 21 Leishmania species and 30 sandfly vectors have been implicated in human leishmaniasis. Leishmaniasis is endemic in 88 countries, 72 are developing countries. Currently, 350 million people live in leishmaniasis-endemic areas around the world. The true incidence of the disease is not known. However, the estimated incidence for visceral leishmaniasis is 500,000 cases per year, and for cutaneous and mucocutaneous leishmaniasis 1.5-2 million cases per year. Visceral leishmaniasis causes 70,000 deaths each year. In the Americas region, …

Sustainable Disposal Of Brine, Bijoy Krishna Halder

Open Access Theses & Dissertations

To meet growing water demand, more water is being harvested from nontraditional sources like brackish water from deep underground aquifers. Since these sources contain salts, drinkable water is produced by separating salt and other minerals (TDS, Total Dissolved Solids) from water through a process commonly known as desalination. A typical desalination plant produces 50-60% potable water from brackish water and the remaining water (brine) is disposed in evaporation ponds or by injecting it below the ground surface. To maximize the limited water supply, inland desalination plants have developed technologies to reduce brine production commonly known as zero liquid discharge (ZLD) …

Ecology Of The Rock Rattlesnake, Crotalus Lepidus, In The Northern Chihuahuan Desert, Vicente Mata Silva

Open Access Theses & Dissertations

The Rock Rattlesnake, Crotalus lepidus is a small species that is found from southern Arizona, southern New Mexico, and southern Texas, in the U.S., into northern Mexico. To date, little is known about the ecology of this species. Ecological information is becoming desperately needed for supporting the conservation and protection of species living in fragile environments such as the Chihuahuan Desert amid current local and global threats (e.g., habitat destruction and modification, urban development, and climate change). Although rattlesnakes spend a significant amount of time underground while overwintering, little is known about the physiology and behavior of these organisms during …

Altered Leptin Signaling On Dendritic Cells As A Potential Mechanism For Cancer Immunotherapy, Lorena Y. De Los Santos

Open Access Theses & Dissertations

Leptin is a pleiotropic hormone synthesized primarily by white adipocytes and its receptors are expressed in a variety of tissues and cells such as in the hypothalamus and cells of the immune system. Multiple cell types can produce a considerable amount of leptin such as skeletal muscle, placenta, and osteoblasts to name a few and its synthesis has been shown to be regulated by sex hormones and a broad range of inflammatory mediators. Although leptin has been shown to directly affect immune response, we are interested in how leptin affects dendritic cell function and their ability to induce a proper …

Causes And Consequences Of Changes In Algal Community Structure Of Arctic Tundra Ponds From Barrow, Alaska, Mariana Vargas Medrano

Open Access Theses & Dissertations

Algal communities in the Arctic are highly sensitive to environmental change, such as longer growing seasons and changes in ice cover. On the north slope of Alaska, ponds and lakes cover large portions of the total land area. We surveyed the periphytic algal communities in tundra ponds from Barrow, Alaska to assess environmental effects on their populations. Samples were collected in August 2008-10 from two main study areas: the IBP (the International Biological Program), which was also studied in 1970-71 but now is located near to human settlements, and the BEO (Barrow Environmental Observatory), which is within a protected area. …

Phospholipid Analysis In Trypanosoma Cruzi, Melissa Rashonda Harris

Open Access Theses & Dissertations

Chagas disease, caused by the flagellate protozoan Trypanosoma cruzi is one of the most endemic and deadly infectious diseases. T.cruzi is distributed throughout most of South and Central America, where it infects 12 to 19 million people, with an annual incidence of 561,000. Another 35 million are exposed to infection, 2 to 3 million people have clinical symptoms of chronic Chagas disease, and about 45,000 of these may die every year due to cardiac failure. In addition to the growing number of incidences in other countries the disease is an emerging infectious disease in the U.S due to the migration …

Phylogeography Of Northern Populations Of The Black-Tailed Rattlesnake (Crotalus Molossus Baird And Girard, 1853) With The Revalidation Of C. Ornatus Hallowell, 1854, Christopher Anderson

Open Access Theses & Dissertations

The black-tailed rattlesnake (Crotalus molossus Baird and Girard, 1853) is a wide-ranging species complex with representatives from the southwestern United States through the highlands of central and southern Mexico. The systematics of this group has received little attention and in the past six decades only two taxonomic revisions have been proposed (the transfer of C. basiliscus oaxacus to C. molossus and the elevation of C. m. estebanensis to full species). However, a recent revision of the Neotropical rattlesnakes (C. durissus and C. simus) recovered a polyphyletic C. molossus. Sequenced data were obtained from three mitochondrial genes …

Ecogeographical Distribution Of The Herpetofauna Of Indio Mountains Research Station, Hudspeth County, Texas, Ross Owen Couvillon

Open Access Theses & Dissertations

Indio Mountain Research Station (IMRS) in Trans-Pecos, Texas is dominated by Chihuahuan Desert scrub vegetation, but a complexity of plant communities exist relating to elevation, slope, and geologic formations. Surrounding the Indio Mountains are desert grasslands with various desert scrub associations. This mosaic of habitats forms a unique assemblage of amphibians and reptiles. The goal of this study was to determine if the current number of amphibians, turtles, lizards, and snakes (43 species) of IMRS was accurate and identify which biotic and abiotic factors define the distribution of these species. Records from the last approximately 25 years were used to …

Structural Investigation Of Atp-Utilizing Enzymes: Structures Involved In H+ Homeostasis And The Proliferation Of Hormone-Dependent Cancers, Zacariah Louis Hildenbrand

Open Access Theses & Dissertations

ATP is a multifunctional nucleotide considered to be the "molecular unit of currency" of intracellular energy transfer. ATP is utilized ubiquitously for the transport of chemical energy within the cell in addition to acting as a substrate in the regulation of many metabolic and signaling transduction pathways such as kinase-mediated signaling cascades. Interestingly, the functional mechanisms of many enzymes require the binding of ATP to trigger key structural and conformational changes that ultimately result in enzyme-directed catalysis. Two of the most omnipresent ATPases within the cell include the V-ATPase rotary proton pump and the Hsp90 protein-folding chaperone. Structural and biochemical …

Fabrication Of Miniature Drug Screening Platform Using Low Cost Bioprinting Technology, Jorge Ivan Rodriguez

Open Access Theses & Dissertations

In the pharmaceutical industry, new chemicals and substances are being tested to find appropriate compounds or mix for treating a specific disease. The demand for screening large compound collections against and increasing number of therapeutic targets has stimulated technology development in the areas of assay automation and miniaturization. Current methods for evaluating the reactions of cells use a volume in the range of microliters. We have developed a new and low-cost deposition method to fabricate miniature drug screening platform that can realistically and inexpensively evaluate biochemical reactions up to 4 substances per trial in a picoliter-scale volume. This paper describes …

Systematics Of The Genus Ptychadena Boulenger, 1917 (Anura: Ptychadenidae) From Democratic Republic Of The Congo, Katrina Marie Weber

Open Access Theses & Dissertations

This thesis increases the scope of previous phylogenetic analyses that revealed high levels of genetic differentiation within the anuran genus Ptychadena. Herein, I increase sampling of Central African populations of Ptychadena by over six times to examine their relationships to other African populations and to search for cryptic species. This study represents the most comprehensive molecular phylogeny of Ptychadena to date. A total of three mitochondrial (12S, 16S, and cyt b) and two nuclear (RAG1 and rhodopsin) genes were sequenced for 67 specimens of Ptychadena. Maximum parsimony, maximum likelihood, and Bayesian analyses were conducted. These analyses revealed …

Identification Of A Novel Cytokine Inducible Stat5 Phosphoserine Site (Ps193) That Positively Regulates Its Transcriptional Activity And Is Found Constitutively Activated In Certain Hematopoietic Cancers, Abhisek Mitra

Open Access Theses & Dissertations

Hematological malignancies such as leukemia and lymphoma, can develop from aberrant changes in the cell signaling molecules to drive their uncontrolled cellular proliferation and differentiation. Activation, maturation, expansion and differentiation of T cells are critically regulated by the dynamics of various transcription factors activated by a variety of cytokines. Additionally, multiple effector molecules that mediate these T cells dependent signals include the JAK (Janus Kinase)-STAT (Signal transducer and activator of transcription) cascade. These signaling proteins are activated in response to a broad array of cytokines. Constitutively activated JAKs and STATs have been described in several T cell malignancies. A growing …

The Effect Of Exogenous Leptin On Murine Dendritic Cell Morphology And Function, Christine Delgado

Open Access Theses & Dissertations

Leptin is a pleiotropic hormone primarily secreted by white adipose tissue. Although originally found to regulate food intake and energy expenditure, it is now known to also significantly affect the immune system. In this study we assessed the effect of leptin on bone marrow derived dendritic cell (BM-DC) cytoskeletal structure and functionality. Our preliminary data demonstrates that the addition of physiological concentrations of exogenous leptin to BM-DC causes cytoskeletal rearrangement specifically that of actin as evidenced by increased number of llamelopodia/dendrites and increased staining for actin within the llamelopodia/dendrite region. This suggests that leptin is a necessary component of DC …

Development And Validation Of A High Throughput, Elisa Morales

Open Access Theses & Dissertations

Not Required

Effect Of Redox-Cycling Agents On Nitric Oxide Synthase Activity In Vitro And Modulation Of Protein Expression In Vivo: No Nitric Oxide Synthase In Mitochondria, Priya Venkatakrishnan

Open Access Theses & Dissertations

This Dissertation describes studies conducted in three areas dealing with the interaction of redox-active compounds with the flavin- and heme- containing enzyme, neuronal nitric oxide synthase (NOS). They are as follows:

I. Studies were initiated using extracts from several varieties of tobacco to identify constituent(s) that could interact with nNOS. Results from [¹⁴C]-L-arginine to [¹⁴C]-L-citrulline conversion assays to which tobacco extracts were individually added, indicate that there are nNOS inhibitors present in tobacco and they are non-polar, lipophilic and non-volatile in nature. In addition, results from assays in which the tobacco-derived redox-active compound, 2,3,6- …