Life Sciences Commons^™

Biology And Ecology Of Aedes (Stegomyia) Aegypti In The Northern Chihuahuan Desert, Adam Joseph Vera

Open Access Theses & Dissertations

Aedes aegypti is a medically important mosquito species that transmits multiple arboviruses, including dengue, chikungunya, Zika, and yellow fever. This mosquito species has expanded its geographical range into expanded into the Northern Chihuahuan Desert to further increase the risk of infection by these viruses in naïve human populations. Although Ae. aegypti is abundant along the U.S.â??Mexico border, the biology and ecology of this mosquito species in this temperate/arid climate region is not understood. The objective of this study was to understand the environmental factors that influence the invasive species of Ae. aegypti abundance, breeding habitat selection, host feeding behavior, and …

Impact Of Agricultural Practices On The Consumptive Water Use Of Irrigated Annual And Perennial Crops Of Northern Mexico And The U.S. Southwest., Orlando Ramirez-Valle

Open Access Theses & Dissertations

In drylands, crop water use varies considerably where high temperatures and limited water availability constraints farming activities, and irrigation planning is essential for the efficient water use and long-term sustainability of agriculture. However, despite dwindling water supplies and the looming threat of more frequent and intense droughts, low-efficient irrigation (e.g., furrow and flooding) continues to be the most widely used method for water delivery into agricultural parcels. Transitioning into more sustainable agriculture requires knowledge of the period of productive vs. unproductive crop water use during the agricultural cycle. I developed a method using satellite images for partitioning evapotranspiration (ETa) into …

Region Detection & Segmentation Of Nissl-Stained Rat Brain Tissue, Alexandro Arnal

Open Access Theses & Dissertations

People who analyze images of biological tissue rely on the segmentation of structures as a preliminary step. In particular, laboratories studying the rat brain delineate brain regions to position scientific findings on a brain atlas to propose hypotheses about the rat brain and, ultimately, the human brain. Our work intersects with the preliminary step of delineating regions in images of brain tissue via computational methods.

We investigate pixel-wise classification or segmentation of brain regions using ten histological images of brain tissue sections stained for Nissl substance. We present a deep learning approach that uses the fully convolutional neural network, U-Net, …

Morphine-Induced Tolerance Is Reduced By The Consumption Of A Ketogenic Diet, But Not A High Fat/High Carbohydrate Diet, Nina Beltran

Open Access Theses & Dissertations

Opioid drugs like morphine are used medicinally for pain relief, but also have abuse liability that can lead to opioid use disorder (OUD), which contributes to nearly 70% of drug overdose deaths in the United States. Another rising health concern is the global obesity epidemic, and new evidence suggests that obesity and OUD might converge to impact individuals. For example, high body mass index (BMI) is associated with greater reports of pain among women. Further, opioid overdose risk is increased among individuals diagnosed with obesity, suggesting a potential relationship that might convey enhanced vulnerability among some populations. Given the high …

In Vitro Characterization Of Novel Compounds With Anti-Cancer Activity, Edgar Alonso Borrego Puerta

Open Access Theses & Dissertations

Two libraries of chemical compounds were analyzed for their cytotoxic activity against cancer and non-cancerous cell lines. In chapter 1, fourteen novel piperidones were tested on a panel of different cell lines to identify their cytotoxic activity. These compounds were found to have cytotoxic activity toward cancer cells with a cytotoxic concentration 50 (CC50) in the micromolar range. Furthermore, these fourteen compounds have selectivity preferentially towards cancer cells. Based on selectivity, and cytotoxicity, four compounds were selected for further characterization in the HL-60 cell line. The four compounds elicit apoptosis as measured by the externalization of the phospholipid phosphatidylserine (PS), …

What Makes Gpcrs From Different Families Bind To The Same Ligand?, Kwabena Owusu Dankwah

Open Access Theses & Dissertations

G protein-coupled receptors (GPCRs) are the largest class of cell-surface receptor proteins with important functions in signal transduction and often serve as therapeutic drug targets. With the rapidly growing public data on three-dimensional (3D) structures of GPCRs and GPCR-ligand interactions, computational prediction of GPCR ligand binding becomes a practical option for high throughput screening and other experimental approaches during the beginning phases of ligand discovery. In this work, we set out to computationally uncover and understand the binding of a single ligand to GPCRs from several different families. We analyzed the sequences and 3D structures of GPCRs from various families …

Effects Of Eccentric Cycling On Blood Flow Patterns And Vascular Reactivity, Manuel Gomez

Open Access Theses & Dissertations

Decrease of blood flow to tissues, due to atherosclerotic plaque formation, produces mortality and morbidity outcomes. Vascular homeostasis depends in the direct interaction between blood flow and endothelial cells, known as endothelial sheer stress (ESS). In addition, turbulent flow, which can be measured by Reynolds number (Re), has been associated with decrease ESS. Eccentric exercise (ECC) has gained attention as a novel exercise modality that increases muscle performance without increasing metabolic demands; however, little is known about ESS during ECC. PURPOSE: To determine the effects of ECC cycling in blood flow patterns and vascular reactivity in young, healthy individuals. METHODS: …

Exploring The Anticancer Mechanism Of Thienopyrazole Derivative Tpz-1 In Acute Myeloid Leukemia, Jessica Dyanne Hess

Open Access Theses & Dissertations

Anticancer drug discovery is a time and resource-consuming process for which exceedingly reliable and efficient modern approaches are needed. Phenotypic drug screenings can generate highly potent and innovative drug candidates; however, deconvolution of the drugâ??s target often presents significant barriers to drug development. To overcome this hurdle, we have originally combined in vitro and in silico analyses to uncover the molecular mechanism(s) driving the anticancer activity of the uniquely structured small molecule drug candidate, Tpz-1. Our study revealed that Tpz-1 is a multitargeted agent which induces the programmed death of HL-60 acute myeloid leukemia cells primarily through disruption of microtubule …

Biology And Epidemiology Of Dengue Viruses In The El Paso And The Surrounding Usa And Mexico Border Communities, Pedro Miguel Palermo Infante

Open Access Theses & Dissertations

Dengue is considered one of the most important human arboviral diseases worldwide. Dengue cases have increased in the last three decades in the Americas, especially along the United States (US)- Mexico (MX) border region, where the main vector of dengue, Aedes aegypti mosquito, is widely distributed. Explosive outbreaks of dengue in northern Mexico have been associated with imported and local transmission of dengue in the US border communities, especially in the Southeast Texas area, also known as Rio Grande Valley. Due to the unknown if dengue virus (DENV) is present in other areas in the US border located west of …

A Comparison Of Spatial-Temporal Gait Variability In Over-Ground And Treadmill Walking In Children With Autism, René Ubaldo Sanchez

Open Access Theses & Dissertations

Children with Autism Spectrum Disorder (ASD) experience an increased sedentary lifestylewhich results in elevated risk for being overweight and obese. A low-cost and viable solution to increase physical activity while accommodating for social-behavioral barriers such as stereotypy, aggressive, or non-verbal characteristics, may be treadmill-related interventions. Gait variability during treadmill ambulation has not been extensively researched in the ASD population, therefore the aim of this study was to quantify the acute effects of treadmill usage on spatial-temporal gait parameter variability when compared to overground walking. Three-dimensional kinematic data were obtained through motion analysis where 5 children with ASD were outfitted with …

Two Novel Piperidone Compounds Display Antiproliferative Effects On Human Prostate And Lymphoma Cancer Cell Lines And In Vitro Investigation Of Thiophenecarboxylate Anti-Cancer Activity, Risa Mia Swain

Open Access Theses & Dissertations

Tumor interactions predominantly dominate cancer progression and its tumor microenvironment. Such interactions include, tumors generating signals that cause dysfunction and death to immune cells [1]. Inflammatory and immune cells present to eliminate cancer cells fail and lose their overall function [1]. These cells lose the overall ability to aid and are co-opted to promote tumor growth. Ultimately, the result is escaping from the hosts' immune system and developing a complex mechanism that evades immune cells and the inability to undergo apoptosis. It is imperative to develop a better understanding of the complex machinery cancer develops. There are current therapies that …

Inhibiting C-C Chemokine Receptor 7 Activation Of T-Cell Acute Lymphoblastic Leukemia By A Ccl19/Macrophage Inflammatory Protein-3Β Antagonist, Angel Torres

Open Access Theses & Dissertations

The binding of C-C Chemokine Ligand 19 (CCL19) to C-C chemokine receptor 7 (CCR7) receptor has been linked to T-cell activation, tolerance, and inflammation. CCR7 is a member of the chemotactic cytokine family, essential in the development of T cells and regulatory processes such as immune-cell trafficking. This is accompanied by chemokine ligand concentration and time-dependent internalization, which is efficiently promoted by CCL19. A novel N-terminal truncation of CCL19 has been previously developed as an antagonist observed to impede induced chemotaxis and calcium mobilization in mouse primary immune cells. The current antagonist has suggested a key role of CCL198-83 in …

Acute Effects Of Neuromuscular Electrical Stimulation On Blood Glucose And Energy Metabolism In Overweight/Obese Population, Ali Mossayebi

Open Access Theses & Dissertations

Background: In the perspective of preventing cardiovascular disease and promoting health, weight control and physical activity are the main concerns. Electrical stimulation (ES) is an alternate strategy to induce muscle contraction, using electrical impulses. However, effectiveness of ES induced muscle contraction to improve energy expenditure and glucose metabolism is not well examined.Purpose: To determine the acute effect of ES on whole body energy expenditure and body glucose metabolism in sedentary overweight or obese population Methods: Sedentary overweight/obese participants (n=8; age: 37.25 ± 6.09 years; BMI= 37.57 ± 2.43 kg/m2) were included in this study. All participants received bilateral quadriceps ES …

Insights On The Behavior Of Nano-Copper In The Agroecosystem: Mycorrhizal Associations With Spearmint (Mentha Spicata), Suzanne Annette Apodaca

Open Access Theses & Dissertations

Nanotechnology offers significant potential benefits to our society, including the agriculture sector. With the advancement of nano-enabled agrochemicals towards sustainable and efficient agricultural practices, it is essential to address environmental issues associated with the use of nanoscale materials. The same properties that give promise to applications of nanotechnology in modern agriculture could have unintended consequences on ecosystem dynamics. A point of concern for risk management is the impact of engineered nanomaterials (ENMs) to beneficial microbial communities, which support a variety of ecosystem services.

Use of copper (Cu) products in agriculture are based on their abundance, role as a micronutrient, and …

Autoantibody Against Tumor-Associated Antigens As Diagnostic Biomarkers In Hispanic Patients With Hepatocellular Carcinoma, Yangcheng Ma

Open Access Theses & Dissertations

Liver cancer is one of the most prevalent malignancies, in which hepatocellular carcinoma (HCC) takes up more than 80% of liver cancer cases. Early diagnosis and treatment are practical approaches to impede HCC progression. Identifying and classifying autoantibodies against tumor-associated antigens (TAAs) have long been interested in cancer diagnosis, especially for HCC. Circulating anti-TAA autoantibodies amplify the antigen expression and are more stable in blood, guaranteeing anti-TAA autoantibodies as valid diagnostic biomarkers in clinical application. Nonetheless, very few studies had focused on the Hispanic HCC group, which might retain distinct etiological risk factors compared to other ethnicities. The high incidence …

Landscape Genomics Of The Tussock Cottongrass (Eriophorum Vaginatum) And The Dwarf Birch (Betula Nana) In North Central Alaska, Elizabeth Stunz

Open Access Theses & Dissertations

Global climate change has resulted in geographic range shifts of flora and fauna at a global scale. Extreme environments, like the Arctic, are seeing some of the most pronounced changes. This region covers 14% of the Earthâ??s land area, and while many arctic species are widespread, understanding ecotypic variation at the genomic level will be important for elucidating how range shifts will affect ecological processes. Increase in shrub cover is a major effect of ongoing climate change in arctic tundra ecosystems. The relative increases in abundance and cover of shrub species such as birch, willow, and alder (Betula, Salix, and …

Survey Of Fleas And Ticks For Rickettsia Rickettsii And Rickettsia Typhi And Surveys Of Humans And Wild Animals For Serological Evidence Of Infection By These Rickettsiae In Rural And Urban Areas Of El Paso, Texas And Other Areas Of Texas, Karen Rocio Valdez

Open Access Theses & Dissertations

The ecology and epidemiology of Rocky Mountain Spotted fever and typhus fever pathogens are poorly understood along the United Statesâ??Mexico border, especially in the far Southwestern region of Texas. The objective of this dissertation was to understand the prevalence and distribution of Rickettsia rickettsii and Rickettsia typhi and associated tick and flea species and the prevalence of these Rickettsiae in domestic and feral mammals in urban and rural areas of the El Paso community and other areas of Texas. Also, the goal was to determine if humans are being infected by R. rickettsii and R. typhi in the El Paso …

Impact Of Agricultural Practices On The Consumptive Water Use Of Irrigated Annual And Perennial Crops Of Northern Mexico And The U. S. Southwest., Orlando Ramirez-Valle

Open Access Theses & Dissertations

In drylands, crop water use varies considerably where high temperatures and limited water availability constraints farming activities, and irrigation planning is essential for the efficient water use and long-term sustainability of agriculture. However, despite dwindling water supplies and the looming threat of more frequent and intense droughts, low-efficient irrigation (e.g., furrow and flooding) continues to be the most widely used method for water delivery into agricultural parcels. Transitioning into more sustainable agriculture requires knowledge of the period of productive vs. unproductive crop water use during the agricultural cycle. I developed a method using satellite images for partitioning evapotranspiration (ETa) into …

Land Use/ Land Cover Change Patterns And Trends In Two Dryland Regions, Omar Sulaiman Belhaj

Open Access Theses & Dissertations

Development and climate change affect the environment in numerous ways and to varyingdegrees. This effect appears prominent and more influential in arid regions. Therefore, land use/ land cover in these regions experience profound changes such as plant cover decrease and extinction of some plant species. Also, land use/ land cover in these regions has critical impacts on the environment and its components, such as shrublands shrinking and losing the habitat of animal species. The degree of changes and effects reaches severe levels that become urgent to figure out the impacts and find solutions to stop or mitigate the negative consequences. …

Development Of A Ph-Triggered Cargo Delivery System With Esxa Mutants, Shuchen Chen

Open Access Theses & Dissertations

Tuberculosis (TB) is a communicable disease caused by Mycobacterium tuberculosis (Mtb). It was the leading cause of human death generated by a single infectious agent before the Coronavirus (COVID-19) pandemic. Mtb has a special mechanism to evade the hostâ??s immune system and utilize macrophages as reservoirs. Latent TB infections have been a threat to public health. Liposome has been widely used for drug delivery. Immunoliposomes are special liposome carriers coated with ligands, such as antigens, targeting certain cells or organs to regulate the uptake of liposome. By constructing the liposome components, or surface modification, cargo release of liposome can be …

Eluication Of Lipid Metabolic Pathways In Differentiating Giardia Lamblia Using High Resolution Mass Spectrometry, Cameron Ellis

Open Access Theses & Dissertations

Giardia lamblia is an intestinal protozoan found worldwide, including the U.S. This parasite exists in two morphologic stages - a replicative trophozoite and a relatively dormant yet viable cyst. While exposures of cysts to gastric acid during passage through the human stomach induces excystation, factors in the small intestine, where trophozoites colonize trigger encystation or cyst formation. Transformation into cyst stage is essential for Giardia to survive in the environment for months before infecting new hosts. Because of its small genome size (11.7 Mb), metabolic pathways in Giardia are highly reduced. As far as lipid metabolism is concerned, only limited …

Tools To Advance Environmental Monitoring, Wetland Restoration And Education In The Desert Southwest, Anna Elisa Pina

Open Access Theses & Dissertations

The relatively rare freshwater ecosystems in the southwestern United States serve as biodiversity hotspots, yet they are among the most threatened systems in the world due to human impacts and climate change. Despite their importance to this arid landscape, the aquatic communities of desert wetlands remain relatively understudied. To restore and create new wetland habitats, effluent is becoming a more commonly used water source for these habitats. However, the effects of byproducts within the treated wastewater on these unique systems have not been well studied. In this study, we aim to better understand the factors that drive water quality and …

Characterization Of Esxa/Esxb Heterodimer Membrane Interaction With A Novel Popc/Popg Liposome Model, Salvador Vazquez Vazquez Reyes

Open Access Theses & Dissertations

EsxA and EsxB are co-secreted as a heterodimer and have been shown to play critical roles in phagosome rupture and translocation of Mycobacterium tuberculosis into the cytosol. Current in vitro studies support a model in which the EsxA:EsxB heterodimer is dissociated upon acidification, which might allow EsxA insertion into liposome membranes. While the membrane permeabilizing activity (MPA) of EsxA has been well characterized in liposomes composed of di-oleoyl-phosphatidylcholine (DOPC), the MPA of EsxA:EsxB heterodimer has not been detected with the DOPC liposome. In this study, we established a new in vitro membrane assay to test the MPA of EsxA and …

Metal Accumulation In Soils, Invertebrates, And Whiptail Lizards In The Northern Chihuahuan Desert, Allyson Benson-Pedraza

Open Access Theses & Dissertations

Smelting activities by the American Smelting and Refining Company (ASARCO) lead to the substantial release of metal pollution into the El Paso, Texas, and border cities region. To-date few studies have examined metal accumulation within vertebrate taxa in these areas. As reptiles are currently experiencing population declines globally for a variety of reasons including pollution, lizards were chosen to be evaluated for trace element (As, Cu, Cr, Cd, Pb, and Zn) concentrations. These metals were measured within soils, invertebrate prey items, and the livers of three species of whiptail lizards (Aspidoscelis) from the un-remediated University of Texas at El Paso …

Chihuahuan Desert Rock Pool Community Assemblages: Patterns Of Taxonomic Diversity, Joseph Lee Mcdaniel

Open Access Theses & Dissertations

As climate change continues to become more prevalent, increasing temperatures and altering precipitation patterns will disrupt the environmental balance of ecosystems and spark the imminent threat of a 6th mass extinction event. Many researchers believe this has already begun, as losses for numerous taxonomic clades have been well documented; however, the loss of invertebrates is still unknown and may be much more severe than those of other animal clades. A significant factor contributing to the shortfall of invertebrate biodiversity loss is rooted in the lack of understanding of the diversity and distribution of these animals. There is still much to …

Water Sourcing Strategies Of Desert Vegetation In Varying Soil Textures With Vegetation Competition: A Stable Isotope Analysis, Martha Elizabeth Gardea

Open Access Theses & Dissertations

Recent studies have suggested an ecohydrological separation of water exists in the northern Chihuahuan Desert, where vegetation types, rainfall regimes, and location in the terrain seem to determine the type of water (e.g. isotopically depleted or enriched in 18O and 2H) plants are able to source and use throughout their growing cycle. That work found evidence of creosote (Larrea tridentata) and mesquite (Prosopis glandulosa) using tightly bound soil water at both a site on an ephemeral channel and a site in higher elevated flat area because the isotopic signature of plant water at the beginning of the study did not …

Population Genetics Of Two Sympatric Species, The Round-Tailed Horned Lizard (Phrynosoma Modestum) And The Greater Earless Lizard (Cophosaurus Texanus), In The Indio Mountains Of West Texas, Logan Miles Horne

Open Access Theses & Dissertations

Population genetics of two sympatric species, the round-tailed horned lizard (phrynosoma modestum) and the greater earless lizard (cophosaurus texanus), in the Indio mountains of West Texas.

Utilizing Computational Methods To Study The Biomolecules, Wenhan Guo

Open Access Theses & Dissertations

COVID-19 is increasingly affecting human health and global economy. Understanding the fundamental mechanisms of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) is highly demanded to develop treatments for COVID-19. SARS-CoV and SARS-CoV-2 share 92.06% identity in their N protein RBDs' sequences, which results in very similar structures. However, the SARS-CoV-2 is more easily to spread. Utilizing multi-scale computational approaches, this work studied the fundamental mechanisms of the nucleocapsid (N) proteins of SARS-CoV and SARS-CoV-2, including their stabilities and binding strengths with RNAs at different pH values. Electrostatic potential on the surfaces of N proteins show that both the N proteins …

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, …

Understanding The Anticancer Mechanism Of Oridonin Using Proteomics Approach, Xiaojun Zhang

Open Access Theses & Dissertations

Oridonin has attracted extensive attention from cancer biologists ascribed to its outstanding anticancer ability. It is a kaurane diterpene, the first bioactive natural compound from Rabdosia rubescens (Hemsl.) Hara, a natural herb. Oridonin is conventionally used as an anti-tumor, ani-inflammatory, antioxidant, and anti-bacterial compound as well as an adjunct treatment for many cancers, especially gastrointestinal tumors, such as esophageal and liver cancers. Its antitumor effects have been connected to its interference with several pathways involved in apoptosis, cell cycle arrest, cell proliferation, autophagy, and cell migration. Presently, both the molecular chaperone Hsp70 and Nucleolin have been identified as targets interacting …