Life Sciences Commons^™

Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano

Open Access Theses & Dissertations

Glucocorticoids are a class of steroid hormones that can either be produced synthetically or naturally by the adrenal glands. The synthetic glucocorticoids are highly prescribed in the United States for their anti-inflammatory and immunosuppressive properties to treat a variety of ailments and diseases; however, these have been implicated in a number of adverse human conditions such as obesity, metabolic syndrome, immune-suppression, delayed puberty, adrenal insufficiency and Cushing Syndrome, among others. Ongoing research has shown that synthetic and natural hormones are transported to aquatic environments via mammalian excretion or wastewater effluent, and as a result, the release of glucocorticoids into the …

Identification Of Chemotherapeutic Agents Against Leishmaniasis And Chagas' Disease, Miguel Abran Vasquez

Open Access Theses & Dissertations

Patients with clinical manifestations of leishmaniasis and Chagas' disease rely on few drugs that have limited efficacy and considerable side effects. Expanding the diversity of available chemotherapeutic drugs for these diseases is of extreme medical importance. Enones or á,í¢-unsaturated ketones, initially developed as anti-cancer agents, are a worthy of class of compounds to test for activity against Leishmania major and Trypanosoma cruzi as these eukaryotic parasites share many of the characteristics exhibited by cancer cells. The anti-parasitic activity of a library of á,í¢-unsaturated ketones (136 derivatives) was screened against L. major as well as in mammalian cells. Three compounds (NC901, …

Assessment Of Water Quality And Benthic Macroinvertebrate Community In A Wastewater Receiving Constructed Wetland, Jennifer Lynn Martinez

Open Access Theses & Dissertations

In the El Paso region around the 1930s there was a loss of riparian areas and wetlands due to canalization of the Rio Grande. In an attempt to bring back native flora and fauna that once flourished in the floodplain of the Rio Grande region, the creation of Rio Bosque Wetlands Park (RBWP; El Paso Co., TX) was initiated in 1995. As part of the construction agreement, El Paso Water Utilities agreed to provide water to fill the wetland upon its completion. Beginning in 1998, RBWP was filled with treated effluent from the adjacent Roberto Bustamante Wastewater Treatment Plant (WWTP) …

Influences Of Ecological Light Pollution On Advertisement Calls Of Spea Multiplicata (Amphibia: Anura: Scaphiopodidae) In Rural And Urban Populations In The Northern Chihuahuan Desert And An Evaluation Of Hybrid S. Bombifrons X S. Multiplicata Calls, Katie Anderson

Open Access Theses & Dissertations

Spea is a genus of toad-like, arid adapted frogs distributed throughout much of the western U.S. and northern Mexico. Two species, (S. Bombifrons and S. Multiplicata) are syntopic throughout most of the northern Chihuahuan Desert, a region that is experiencing rapid urbanization. For this study, I examined 936 male advertisement calls from urban and rural populations of S. multiplicata, and a rural population of S. bombifrons in west Texas and south-central New Mexico. Advertisement calls from urban and rural S. multiplicata were compared against light level to assess the potential influence ecological light pollution plays in sexual …

Ruthenium-Azole Complexes As Chemotherapeutic Agents Against Leishmaniasis, Eva Iniguez

Open Access Theses & Dissertations

Leishmaniasis is a neglected disease that affects millions of people worldwide. Poor efficacy and high toxicity of the limited treatment options demonstrate the need for the development of new chemotherapeutic agents to treat this disease. In order to respond this concern, the development of novel Ru-azole complexes as chemotherapeutic agents by inhibiting the cytochrome P-450 dependent C14-α-demethylation of lanosterol to ergosterol which is essential for the parasite survival. In addition, Ruthenium would enhance the activity of the parental drug, by helping ketoconazole/clotrimazole to cross the parasite membrane, together presenting low toxicity. The viability and citotoxicity of the Ru-azole compunds was …

A Revision Of The New World Ants Of The Genus Platythyrea Roger 1863 (Hymenoptera: Formicidae), Mayra Janett Leyva

Open Access Theses & Dissertations

The genus Platythyrea consists of arboreal ants that are rarely collected. The genus was last partially revised in 1975 by Brown. Since that revision two additional species have been described. The New World genus Platythyrea now includes nine species: P. angusta Forel, P. exigua Kempf, P. lenca De Andrade, P. pilosula (Smith), P. prizo Kugler, P. punctata (Smith), P. sinuata (Roger), P. strenua Wheeler and P. zodion Brown. A new key, illustrations, diagnoses and distributions of the ants are provided.

Identification Of Kinase Signaling Pathways Inducing Morphological Changes In Dendritic Cells Upon Leptin Treatment, Marisol Ann O'Neill

Open Access Theses & Dissertations

Leptin is a pleiotropic hormone secreted by white adipose tissue. Obesity leads to overexpression of leptin as a result of leptin receptor desensitization. Obese leptin serum levels (160ng/ml) have been found to enhance immune functions in macrophages, natural killer cells, B cells, T cells, and dendritic cells. Previous data from our lab suggests that obese concentrations of leptin cause morphological changes in DCs, although further studies are required to verify these results. We hypothesized that leptin promotes DC cytoskeletal changes though activation of PI3K signaling. Morphological and functional changes were evaluated in JAWS II immortalized DCs though microscopy, transwell migration, …

Refining Molecular Approaches For Bacterial Source Tracking (Bst) In Texas, Joy Truesdale

Open Access Theses & Dissertations

Bacterial source tracking (BST) is a new science that aids in identifying sources of human and animal fecal contamination of environmental water. There are currently two approaches used in BST, library-dependent and library-independent methods. The fecal bacterium E. coli is often used in library dependent methods because it indicates fecal contamination, has been used in human health risk assessments, and has water quality regulatory significance. A disadvantage of E. coli library dependent BST methods is that identification libraries of E. coli isolated from known fecal sources are needed to identify the sources of E. coli isolated from water samples. Further, …

The Effect Of Exogenous Leptin On Dendritic Cell Migration And Interactions With T Cells, Amanda L. Gonzales

Open Access Theses & Dissertations

Obesity is a complex, chronic disease that has reached epidemic proportions in the United States and shows no indication of receding. It is a state of chronic low-grade inflammation that is initiated by morphological changes in large accumulations of adipose tissue. Leptin is a pleiotropic hormone secreted by adipose tissue, presenting a possible link between obesity and inflammation. In this study, we assessed the effect of leptin on bone marrow-derived (BM) dendritic cells (DC) (BM-DC) function, antigen presenting cells vital for the activation of naí¯ve T cells. Previous data produced in our laboratory established that the addition of leptin to …

Role Of Post-Translational Modifications In The Hiv Cofactor Activity Of Ledgf/P75, Denisse Adriana Gutierrez

Open Access Theses & Dissertations

see document.

International Polar Year (Ipy) Back To The Future (Btf): Changes In Arctic Ecosystem Structure Over Decadal Times Scales, Sandra Villarreal

Open Access Theses & Dissertations

Arctic vegetation communities are responding to climate warming through shifts in species composition and diversity but most observations have been made over relatively short time frames, and/or in association with experimental manipulations. Because vegetation plays a key role in regulating ecosystem productivity, nutrient cycling, surface energy budgets, and trophic interactions in the Arctic, there is a need to better understand shifts in tundra vegetation communities over decadal time scales. Understanding these shifts and their impact on ecosystem structure and function in the Arctic has important implications for predicting the future state of both the Arctic and the Earth System. Long …

Genetic Diversity In Populations Of Epiphanes Chihuahuaensis (Rotifera: Monogononta) In The Northern Chihuahuan Desert, Diego E. Reyes

Open Access Theses & Dissertations

1. Cryptic speciation in zooplankton is a phenomenon that has been recently gaining much attention. This is due in part to advances in molecular techniques which help in the identification of morphologically indistinct species. Organisms that have been traditionally believed to have cosmopolitan distributions are being found to be composed of cryptic species complexes with high levels of genetic divergence among lineages.

2. Epiphanes chihuahuaensis is a member in the Epiphanes senta species complex. In a previous study by Schröder & Walsh (2007), genetic data, along with morphological and reproductive isolation data were employed to help delineate four species within …

Comparison Of Ectoparasitic Mite Loads Between Gonochoristic (Aspidoscelis Marmorata) And Parthenogenic (A. Tesselata) Syntopic Whiptail Lizards (Teiidae) From The Northern Chihuahuan Desert Of Trans-Pecos, Texas, William Dawson Lukefahr

Open Access Theses & Dissertations

The objective of this study was to compare the ectoparasitic loads between two syntopic whiptail lizard species (Teiidae) that differ in their reproductive modes; Aspidoscelis marmorata (bisexual) and A. tesselata (unisexual). The study site was located on Indio Mountains Research Station (IMRS) in a Chihuahuan Desert Scrub landscape in Hudspeth County, Texas. Previous studies conducted at IMRS showed the two species having similar diets, morphology, and reproductive characteristics, but fluctuated in nematode loads. No comparative study of ecotoparasitic mites (Eutrombicula alfreddugesi) between the two species has ever been done.

Aspidoscelis marmorata (n = 141) and A. tesselata (n = 144) …

Endocrine Disrupting Compound 4-Nonylphenol And Neurodegeneration, Jessica Martinez Jurado

Open Access Theses & Dissertations

Neurodegeneration, a progressive loss of nerve cells (neurons), occurs in many neurological disorders including Alzheimer's disease, Parkinson's disease, Schizophrenia, and drug addiction. Cytoskeletal disruption in neurons and aggregation of proteins associated with these disorders is the hallmark of neurodegeneration. However, the cause of neurodegenerative disorders is unknown and currently there are no effective drug treatments. Aging is the most consistent risk factor for developing a neurodegenerative disorder, and recent evidence suggests that environmental factors, which act as endocrine disruptors, pose a risk in the disease process. 4- nonylphenol (4-NP), an endocrine-disrupting compound (EDC), has been shown to affect brain development …