Life Sciences Commons^™

Lizard Communities In A Shifting Landscape: The Current State Of Insectivorous Lizard Communities In The Jornada Basin Between Grassland, Mesquite Dune, And Creosote Bush Habitats In A Semi-Arid Landscape Undergoing Shrubification, Julie Marie Schlichte

Open Access Theses & Dissertations

Lizard communities in arid lands can act as model systems of how diversity and abundance are impacted in the face of ongoing climate variability and change, as they are sensitive to shifts in precipitation, temperature, and changing vegetation structure. The main research question we hope to answer is how the community composition of lizards varies between dominant vegetation types (Mesquite dunes, grasslands, and Creosote Bush flats). Nine sites (3 of each dominant vegetation type) with 16 pitfall traps each (n = 144) were surveyed from June 2016 -- June 2017. 12 lizard species were captured, consisting of 923 total captures …

Repositioning Propranolol To Block Mitogenic Signaling In Breast Cancer, Alexa Noel Montoya

Open Access Theses & Dissertations

Breast cancer is the second most diagnosed cancer among women and is about 30% of all new cases of female cancers each year. It is projected that 1 in 8 every U.S. woman (about 13%) develop invasive breast cancer over the course of her lifetime. While advances in cancer research have made it possible to elucidate several breast cancer genomic subtypes, and develop new novel therapies, many of these agents are associated with significant toxicity, as well as high costs. A retrospective cross-sectional study of 404 breast cancer patients was performed to determine the effect of β-blocker usage on tumor …

Activity Patterns Of Whiptail Lizards (Aspidoscelis) Found In The Northern Chihuahuan Desert, Guillermo Alvarez

Open Access Theses & Dissertations

Traditional lizard pitfall traps were modified to allow organisms to escape, while collecting valuable ecological data. Modified camera traps were capable of detecting the same species as traditional traps in a semi-arid environment, without posing the associated mortality risks. Pitfall-camera traps were used to sample the activity of the Side-blotched Lizard (Uta stansburiana) and the Southwestern Fence Lizard (Sceloporus cowlesi) in an urban wetland during four continuous years. Evaluations on activity pattern and the activity overlap between the two species revealed extensive overlap, with minor but significant seasonal shifts mediating coexistence. Traps were also effective at detecting other reptiles, invertebrates, …

The Role Of The Cholesterol Synthesis Pathway In Primitive Erythropoiesis, Jose Hernandez

Open Access Theses & Dissertations

Erythropoiesis is the process by which new red blood cells (RBCs) are formed and defects in this process can lead to anemia or thalassemia. The GATA1 transcription factor is an established mediator of RBC development. However, the upstream mechanisms that regulate the expression of GATA1 are not completely characterized. Cholesterol is 1 potential upstream mediator of GATA1 expression because previously published studies suggest that defects in cholesterol synthesis disrupt RBC differentiation. Here we characterize RBC development in a zebrafish harboring a single missense mutation in the hmgcs1 gene (Vu57 allele). Hmgcs1 encodes the first enzyme in the cholesterol synthesis pathway …

Development Of Synthetic Glycobiomarkers For The Follow-Up Of Chagas Disease Chemotherapy And Serological And Molecular Assays For Evaluation Of Trypanosoma Cruzi Infections In The U.S-Mexico Border, Igor L. Estevao

Open Access Theses & Dissertations

Chagas disease (CD), caused by the protozoan parasite Trypanosoma cruzi, affects 7-8 million people worldwide. Lately, the disease has been spread to nonendemic countries and regions, like the U.S. and Europe. The disease can be divided into two phases: the acute and chronic phases, which continue for years or even decades. There are two available drugs for CD treatment: benznidazole (BNZ) and nifurtimox (NFX). These drugs are highly effective in the acute phase but less efficient in the chronic stage. Other limitations of these drugs are their toxicity, leading to serious adverse events and premature treatment termination. Newer clinical trial …

Proteomic Analysis Reveals Fkbp51 And Fkbp52 Interactors Implicated In Androgen Receptor-Mediated Castration Resistant Prostate Cancer, Olga Soto

Open Access Theses & Dissertations

Aberrant signaling mechanisms by the Androgen Receptor (AR) are attributed as the main culprits for the initiation and progression of prostate cancer (PCa). Due to its dependence on androgens, research efforts have focused on developing strategies to directly target androgen-mediated receptor activity. However, given the recurrence and treatment resistance of PCa despite androgen targeted therapies, recent efforts have shifted to find novel targets against the disease. These efforts include further revealing the molecular components and their mechanisms underlying AR signaling in both normal and disease physiological settings. Hence, our lab's work is focused on characterizing and targeting molecular chaperones that …

Exploring Undergraduate Research Experiences And Perceptions Of Responsible And Ethical Conduct Of Research (Recr) Education In The Biological Sciences And (Bio)Chemistry Disciplines, Bernice Justina Caad

Open Access Theses & Dissertations

Increasing calls to reform undergraduate (UG) education within science, technology, engineering, and mathematics (STEM) disciplines have emphasized the importance of early exposure to responsible and ethical conduct of research (RECR) education. Historically, RECR has primarily been presented at the post-baccalaureate level, leaving many students without a foundational understanding of what responsible research ethics entails during the course of their undergraduate experience. Over the last decade, course-based undergraduate research experiences (CUREs) have emerged as a promising platform to establish expectations of responsible and ethical conduct through greater accessibility and inclusivity, starting at the freshman level. Interestingly, few studies have examined how …

The Importance Of Soil Carbon In Large-Scale Shrub Removal Practices In The Chihuahuan Desert, Kathleen Schaeffer

Open Access Theses & Dissertations

Shrub encroachment is a worldwide phenomenon that affects multiple biomes at different ecological and anthropogenic levels. In dryland ecosystems, shrub encroachment is a noted concern amongst land managers, as it can lead to a loss of soil resources and biodiversity. To mitigate the negative effects of shrub encroachment in Drylands, land managers can implement large-scale shrub removal practices. These land restoration practices can shift landscapes to novel ecosystems, where resulting plant communities can vary following treatments. Grass recovery or increasing herbaceous cover is often a primary goal of these treatments, however predicting which sites may show higher grass responses to …

Immunoreactivity Of The Serotonin-Like And Fmrf-Amide-Like Nervous Systems Of Four Gnesiotrochan Rotifers, Robert Neil Walsmith

Open Access Theses & Dissertations

Reorganization of the nervous system during metamorphosis is a common phenomenon across taxa (species through phyla). In phylum Rotifera, sessile species belonging to the superorder Gnesiotrocha metamorphose from free-swimming larvae into sessile adults. Once mature, gnesiotrochan rotifers display an intricate corona or infundibulum associated with lifestyle modalities and feeding behaviors. Here, I examine serotonin-like immunoreactivity (SLIR) and FMRF-amide-like immunoreactivity (FLIR) of the gnesiotrochans Lacinularia flosculosa, Collotheca ferox, and Acyclus inquietus with a focus on life stage and sex. Based on previous research, I hypothesize that 1) innervation of the larval nervous system will vary according to the lifestyle constraints observed …

Functional Analysis Of The Gamma-Aminobutyric Acid Type A Receptor Subunit Alpha-1 (Gabra1) Gene During Zebrafish Development., Nayeli Gabriela Reyes-Nava

Open Access Theses & Dissertations

The GABRA1 gene encodes for the alpha-1 (α1) subunit of the Gamma-Aminobutyric acid type A receptor (GABAAR), which are the primary modulators of synaptic inhibition in the central nervous system (CNS). Alpha-1 subunits are essential for maintaining the normal function of native receptors and contribute to over 60% of all GABAARs in the CNS. Remarkably, a broad spectrum of neurodevelopmental and epilepsy-associated disorders have been linked with mutations in the GABRA1 gene. However, the developmental, behavioral, and molecular mechanisms underlying GABRA1-associated epileptic disorders remain to be fully understood. Hence, the overarching goal of this dissertation is to investigate the behavioral …

Investigation Into The Roles Of Esxa N-Α-Acetylation In Pathogenesis Of Mycobacterium Tuberculosis And Potential Host-Binding Proteins, Javier Aguilera

Open Access Theses & Dissertations

EsxA (6-kDa early secreted antigenic target, ESAT-6) is a critical virulence factor of Mycobacterium tuberculosis (Mtb). EsxA is secreted in a heterodimer with EsxB (10-kDa culture filtrate protein, CFP-10) through the Type VII secretion system of Mtb, called ESX-1. The dissociation of EsxA and EsxB heterodimer (EsxA:B), upon acidification, is required for EsxA to penetrate into the phagosomal membranes, which has been implicated in Mtb translocation from the phagosome to the cytosol. However, the mechanism of EsxA:B dissociation is not clear. In this study, we investigated the role of N-α-acetylation of EsxA in the heterodimer dissociation, mycobacterial cytosolic translocation, and …

Linking Decomposition Reactions In Arctic Soils To Microbial Enzyme Production, Jane Karen Martinez

Open Access Theses & Dissertations

Microbial processes such as soil enzyme production are a major driver of decomposition and a current topic of interest in arctic soils due to the effects of climate warming. Despite the advances in understanding soil enzymes, there are still knowledge gaps regarding the role of enzymes in decomposition. In this dissertation, I addressed three of those gaps in the following chapters: (Ch.2) to explore the location of enzymes within the soil matrix, (Ch.3) to identify peptides matched to soil enzymes produced by microorganisms for organic matter decomposition, and (Ch.4) understand the longevity of enzymes in the soil after microbial production. …

Phylogenetics And Integrative Taxonomy Of African Water Snakes (Squamata: Colubridae: Grayia), Teslin Chaney

Open Access Theses & Dissertations

Grayia is a genus of relatively large (1.5 - 2.5 m) aquatic Afrotropical snakes. Recent molecular phylogenies recovered Grayia in its own distinct subfamily (Grayiinae), which was strongly supported as the sister group to Colubrinae. Because tropical African snakes are generally understudied, the relationships within Grayia are poorly known. Due to high degrees of intra- and interspecies variation, identification is often difficult and previous studies involving Grayia included misidentified specimens in other genera. The goal of this study is to create a phylogenetic tree that can be used to understand the relationships and taxonomy of Grayia via an integrative taxonomic …

Neurogenetic Function Of Host Cell Factor-1, Victoria Lynn Castro

Open Access Theses & Dissertations

Neural precursor cells (NPCs) are the stem-like cells of the developing brain. These cells differentiate into the differentiated cell types of the central nervous system. If disruption occurs in the number of total NPCs formed or their survival, various disorders including learning disabilities, behavioral problems, or epilepsy can occur. This dissertation describes how the HCFC1 gene controls the proliferation and differentiation of NPCs. HCFC1 encodes for a transcriptional co-factor that regulates the growth and metabolism of stem cells, including NPCs. Mutations in HCFC1 cause cblX syndrome, a neural developmental disorder that affects the nervous system and causes microcephaly, epilepsy, and …

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), …

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 …

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 …

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 …

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 …

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 …

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 …

Mathematical Modeling Of Potassium Modulated Viral Infection, Zaira Elizabeth Mather

Open Access Theses & Dissertations

In recent years, there is a growing interest in the investigation of using potassium to treat virus infections. In the region of infection, there is a biological observation of extracel- lular potassium level being typically very low whereas the intracellular potassium levels are much higher. There are numerous biological studies showing that elevated potassium levels in the extracellular membrane tends to block virus infections. A recent effort in this direction is a collaborative research conducted by mathematicians and biologists from the University of Texas at El Paso, New Mexico State University, and the University of New Mexico, where we develop …

Generating And Sustaining Meaningful Professional Development Opportunities For Graduate Teaching Assistants Facilitating Course-Based Undergraduate Research Experiences In The Biological Sciences, Amie M. Kern

Open Access Theses & Dissertations

Current national efforts to reform postsecondary laboratory education have emphasized the incorporation of authentic research opportunities into science, technology, engineering, and mathematics (STEM) curricula. Within the last decade, course-based undergraduate research experiences (CUREs) have emerged as a viable mechanism to achieve this goal. Evidence within the biology education literature suggests that student engagement in CUREs has the potential to positively impact their development of scientific inquiry and process skills, content knowledge, and affect in the domain. While the majority of studies have focused on student outcomes, few studies have examined instructor outcomes in CURE learning environments. This is especially true …

Nanotechnology-Based Approaches To Mitigate Environmental Pollutants -- Induced Neurological Disorders, Jyoti Ahlawat

Open Access Theses & Dissertations

Neurodegenerative diseases such as Parkinson's disease (PD), Alzheimerâ??s Disease (AD) and Huntingtonâ??s Disease (HD) have no cure despite intensive research efforts geared towards therapeutics development. In the USA, patients with PD and AD alone cost the nation ~ $200 billion annually in patient care and lost productivity. Therefore, there remains an urgent and unmet need to develop novel drugs and drug carriers with the potential to slow down, halt and ideally reverse the course of neurodegenerative disorders. The dissertation focuses on developing approaches towards targeting PD using multifactorial mechanisms including the targeting of protein aggregation and oxidative stress. This is …

Identification Of Prostate Cancer-Associated Genomic Alterations By Analyzing Variant Frequencies, Functional Effects, And Protein Interactions, Bofei Wang

Open Access Theses & Dissertations

With the ever-increasing varieties of sequencing techniques, the volume and scope of genomic data are explosively expanded, offering unparalleled opportunities for researchers to study gene-disease associations, identify biomarkers, and thus develop more effective diagnostic and therapeutic strategies. In this project, I have developed a computational workflow and a new scoring scheme, which combine statistical frequency-based analyses with two well-established functional effect prediction tools FATHMM and PROVEAN, to evaluate nonsynonymous GSVs and identify potential cancer-related protein-coding genes for downstream enrichment and protein-protein interaction (PPI) studies.

This method has been applied to process a collection of 503 whole exome sequencing datasets for …