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Full-Text Articles in Life Sciences

Metformin Alleviates Hepatic Iron Overload And Ferroptosis Through Ampk-Ferroportin Pathway In Hfd-Induced Nafld, Fangzhi Yue, Ying Shi, Shanyu Wu, Lin Xing, Dan He, Lin Wei, Anqi Qiu, Ryan D. Russell, Dongmei Zhang Dec 2023

Metformin Alleviates Hepatic Iron Overload And Ferroptosis Through Ampk-Ferroportin Pathway In Hfd-Induced Nafld, Fangzhi Yue, Ying Shi, Shanyu Wu, Lin Xing, Dan He, Lin Wei, Anqi Qiu, Ryan D. Russell, Dongmei Zhang

Health & Human Performance Faculty Publications and Presentations

Highlights

  • Metformin alleviates HIO and ferroptosis in HFD-induced NAFLD

  • FPN is involved in the molecular mechanism of metformin on HIO in HFD-induced NAFLD

  • Metformin upregulates FPN expression by reducing lysosomal ubiquitination degradation

Summary

Metformin prevents progression of non-alcoholic fatty liver disease (NAFLD). However, the potential mechanism is not entirely understood. Ferroptosis, a recently recognized nonapoptotic form of regulated cell death, has been reported to be involved in the pathogenesis of NAFLD. Here, we investigated the effects of metformin on ferroptosis and its potential mechanism in NAFLD. We found that metformin prevented the progression of NAFLD, and alleviated hepatic iron …


Social Transmission Of Predator Information Through Referential Alarm Calls Within And Across Species, Carly Trebac Mar 2023

Social Transmission Of Predator Information Through Referential Alarm Calls Within And Across Species, Carly Trebac

Honors Theses

Animals can encode information about a predator’s size, identity, or threat through alarm calls. This can provide referential information that can be used by individuals within and across species receiving the information. Referential alarm calls can encode information through changes in structure or rate of the call, and these variances in their call can elicit different responses, such as fleeing or mobbing, in conspecifics and heterospecifics. We aimed to investigate whether white-breasted nuthatch alarm calls can encode referential information and elicit different responses from conspecifics. Previous studies showed that a related species of nuthatch varies their call rate in the …


Frankenbacteriosis Targeting Interactions Between Pathogen And Symbiont To Control Infection In The Tick Vector, Lorena Mazuecos, Pilar Alberdi, Angélica Hernández-Jarguín, Marinela Contreras, Margarita Villar, Alejandro Cabezas-Cruz, Ladislav Simo, Almudena González-García, Sandra Díaz-Sánchez, Girish Neelakanta, Sarah I. Bonnet, Erol Fikrig, José De La Fuente Jan 2023

Frankenbacteriosis Targeting Interactions Between Pathogen And Symbiont To Control Infection In The Tick Vector, Lorena Mazuecos, Pilar Alberdi, Angélica Hernández-Jarguín, Marinela Contreras, Margarita Villar, Alejandro Cabezas-Cruz, Ladislav Simo, Almudena González-García, Sandra Díaz-Sánchez, Girish Neelakanta, Sarah I. Bonnet, Erol Fikrig, José De La Fuente

Biological Sciences Faculty Publications

(Summary) Tick microbiota can be targeted for the control of tick-borne diseases such as human granulocytic anaplasmosis (HGA) caused by model pathogen, Anaplasma phagocytophilum. Frankenbacteriosis is inspired by Frankenstein and defined here as paratransgenesis of tick symbiotic/commensal bacteria to mimic and compete with tick-borne pathogens. Interactions between A. phagocytophilum and symbiotic Sphingomonas identified by metaproteomics analysis in Ixodes scapularis midgut showed competition between both bacteria. Consequently, Sphingomonas was selected for frankenbacteriosis for the control of A. phagocytophilum infection and transmission. The results showed that Franken Sphingomonas producing A. phagocytophilum major surface protein 4 (MSP4) mimic pathogen and reduce infection …


Pollutants Corrupt Resilience Pathways Of Aging In The Nematode C. Elegans, Andrea Scharf, Annette Limke, Karl Heinz Guehrs, Anna Von Mikecz Sep 2022

Pollutants Corrupt Resilience Pathways Of Aging In The Nematode C. Elegans, Andrea Scharf, Annette Limke, Karl Heinz Guehrs, Anna Von Mikecz

Biological Sciences Faculty Research & Creative Works

Delaying aging while prolonging health and lifespan is a major goal in aging research. One promising strategy is to focus on reducing negative interventions such as pollution and their accelerating effect on age-related degeneration and disease. Here, we used the short-lived model organism C. elegans to analyze whether two candidate pollutants corrupt general aging pathways. We show that the emergent pollutant silica nanoparticles (NPs) and the classic xenobiotic inorganic mercury reduce lifespan and cause a premature protein aggregation phenotype. Comparative mass spectrometry revealed that increased insolubility of proteins with important functions in proteostasis is a shared phenotype of intrinsic- and …


Pparα And Pparγ Activation Is Associated With Pleural Mesothelioma Invasion But Therapeutic Inhibition Is Ineffective, M. Lizeth Orozco Morales, Catherine A. Rinaldi, Emma De Jong, Sally M. Lansley, Joel P. A. Gummer, Bence Olasz, Shabarinath Nambiar, Danika E. Hope, Thomas H. Casey, Y. C. Gary Lee, Connull Leslie, Gareth Nealon, David M. Shackleford, Andrew K. Powell, Marina Grimaldi, Patrick Balaguer, Rachael M. Zemek, Anthony Bosco, Matthew J. Piggott, Alice Vrielink, Richard A. Lake, W. Joost Lesterhuis Jan 2022

Pparα And Pparγ Activation Is Associated With Pleural Mesothelioma Invasion But Therapeutic Inhibition Is Ineffective, M. Lizeth Orozco Morales, Catherine A. Rinaldi, Emma De Jong, Sally M. Lansley, Joel P. A. Gummer, Bence Olasz, Shabarinath Nambiar, Danika E. Hope, Thomas H. Casey, Y. C. Gary Lee, Connull Leslie, Gareth Nealon, David M. Shackleford, Andrew K. Powell, Marina Grimaldi, Patrick Balaguer, Rachael M. Zemek, Anthony Bosco, Matthew J. Piggott, Alice Vrielink, Richard A. Lake, W. Joost Lesterhuis

Research outputs 2022 to 2026

Mesothelioma is a cancer that typically originates in the pleura of the lungs. It rapidly invades the surrounding tissues, causing pain and shortness of breath. We compared cell lines injected either subcutaneously or intrapleurally and found that only the latter resulted in invasive and rapid growth. Pleural tumors displayed a transcriptional signature consistent with increased activity of nuclear receptors PPARα and PPARγ and with an increased abundance of endogenous PPAR-activating ligands. We found that chemical probe GW6471 is a potent, dual PPARα/γ antagonist with anti-invasive and anti-proliferative activity in vitro. However, administration of GW6471 at doses that provided sustained plasma …


Stabilin Receptors Clear Lps And Control Systemic Inflammation, Fatima Cabral, Mustafa Al-Rahem, John Skaggs, Thushara A. Thomas, Naresh Kumar, Qian Wu, Paolo Fadda, Lianbo Yu, John M. Robinson, Jonghan Kim, Ekta Pandey, Xinghui Sun, Wael N. Jarjour, Murugesan V.S. Rajaram, Edward N. Harris, Latha P. Ganesan Nov 2021

Stabilin Receptors Clear Lps And Control Systemic Inflammation, Fatima Cabral, Mustafa Al-Rahem, John Skaggs, Thushara A. Thomas, Naresh Kumar, Qian Wu, Paolo Fadda, Lianbo Yu, John M. Robinson, Jonghan Kim, Ekta Pandey, Xinghui Sun, Wael N. Jarjour, Murugesan V.S. Rajaram, Edward N. Harris, Latha P. Ganesan

Department of Biochemistry: Faculty Publications

Lipopolysaccharides (LPSs) cause lethal endotoxemia if not rapidly cleared from blood circulation. Liver sinusoidal endothelial cells (LSEC) systemically clear LPS by unknown mechanisms. We discovered that LPS clearance through LSEC involves endocytosis and lysosomal inactivation via Stabilin-1 and 2 (Stab1 and Stab2) but does not involve TLR4. Cytokine production was inversely related to clearance/endocytosis of LPS by LSEC. When exposed to LPS, Stabilin double knockout mice (Stab DK) and Stab1 KO, but not Stab2 KO, showed significantly enhanced systemic inflammatory cytokine production and early death compared with WT mice. Stab1 KO is not significantly different from Stab DK in circulatory …


Articulating The Importance Of Broader Relevance In Cures: From Definition To Actualization, Nikki T. Donegan Aug 2021

Articulating The Importance Of Broader Relevance In Cures: From Definition To Actualization, Nikki T. Donegan

Open Access Theses & Dissertations

Course-based undergraduate research experiences (CUREs) have emerged as a means to foster student' scientific reasoning, promote positive attitudes and motivations toward research, and increase persistence in the science, technology, engineering, and mathematics (STEM) fields. In contrast to prescriptive laboratories, students enrolled in CUREs employ techniques and skills to collaboratively and iteratively address novel questions of broad relevance to audiences beyond the scope of the course itself. While many of the core components of CUREs are perceived to be relatively straightforward, definitionally-speaking, this latter dimension of broader relevance has, in contrast, remained largely ill-defined. In the series of studies presented herein, …


Vitamin D3 Induces Mesenchymal-To-Endothelial Transition And Promotes A Proangiogenic Niche Through Igf-1 Signaling, Lei Chen, Anweshan Samanta, Lin Zhao, Nathaniel R. Dudley, Tanner Buehler, Robert J. Vincent, Jeryl Hauptman, Magdy Girgis, Buddhadeb Dawn Apr 2021

Vitamin D3 Induces Mesenchymal-To-Endothelial Transition And Promotes A Proangiogenic Niche Through Igf-1 Signaling, Lei Chen, Anweshan Samanta, Lin Zhao, Nathaniel R. Dudley, Tanner Buehler, Robert J. Vincent, Jeryl Hauptman, Magdy Girgis, Buddhadeb Dawn

School of Medicine Faculty Publications

Biological Sciences; Physiology; Molecular Biology; Cell Biology


Chronic Consumption Of A Western Diet Induces Robust Glial Activation In Aging Mice And In A Mouse Model Of Alzheimer’S Disease, Leah C. Graham, Jeffrey M. Harder, Ileana Soto Reyes, Wilhelmine N. De Vries, Simon W. M. John, Gareth R. Howell Oct 2019

Chronic Consumption Of A Western Diet Induces Robust Glial Activation In Aging Mice And In A Mouse Model Of Alzheimer’S Disease, Leah C. Graham, Jeffrey M. Harder, Ileana Soto Reyes, Wilhelmine N. De Vries, Simon W. M. John, Gareth R. Howell

Ileana Soto Reyes

Studies have assessed individual components of a western diet, but no study has assessed the long-term, cumulative effects of a western diet on aging and Alzheimer’s disease (AD). Therefore, we have formulated the first western-style diet that mimics the fat, carbohydrate, protein, vitamin and mineral levels of western diets. This diet was fed to aging C57BL/6J (B6) mice to identify phenotypes that may increase susceptibility to AD, and to APP/PS1 mice, a mouse model of AD, to determine the effects of the diet in AD. Astrocytosis and microglia/monocyte activation were dramatically increased in response to diet and was further increased …


Effects Of Elevated Temperature On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In Atlantic Sea Urchin (Arbacia Punctulata), Jackson B. Johnstone May 2019

Effects Of Elevated Temperature On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In Atlantic Sea Urchin (Arbacia Punctulata), Jackson B. Johnstone

Theses and Dissertations

Increasing surface sea water temperatures effect on growth, reproduction and development in marine organisms. Sea urchins are excellent indicator species and ideal model organisms to focus on. In this study, I tested the effect of higher temperatures on reproductive functions, heat shock protein (HSP, a chaperone protein produced by cells in response to heat stress) and nitrotyrosine protein (NTP, an indicator of reactive nitrogen species, RNS) expressions, cellular apoptosis, and ceolomic fluid (CF, a body fluid which regulates important physiological processes) conditions in Atlantic sea urchin at three different temperatures. Ten sea urchins were placed in each of six aquariums …


The Snail Communities Of The Lower Rio Grande Valley, Briante Shevon Lewis Najev May 2019

The Snail Communities Of The Lower Rio Grande Valley, Briante Shevon Lewis Najev

Theses and Dissertations

The lower Rio Grande Valley are three lowest latitudinal counties of south Texas. This unique, subtropical, semi-arid environment has the last remaining Tamaulipan Thornforest in the USA. The Tamaulipan Thornforest of Texas occupies less than 2% of their former range. Before this habitat possibly dwindles even more there has been a comprehensive survey of terrestrial snails in intact, altered, and urban areas of the valley.

We have found a 16397 of snails in intact sites with a high species richness at 17; followed by altered sites with an abundance of 12143 snails and a species richness of 15. There were …


Investigating The Efficacy Of Jak2/Stat3 And Pi3k/Mtor Inhibitory Therapy On Glioblastoma And Basal Breast Cancer Cell Lines, Neftali Vazquez May 2019

Investigating The Efficacy Of Jak2/Stat3 And Pi3k/Mtor Inhibitory Therapy On Glioblastoma And Basal Breast Cancer Cell Lines, Neftali Vazquez

Theses and Dissertations

The JAK2/STAT3 and PI3K/mTOR pathways are upregulated in cancer cells. STAT3 promotes a positive feedback loop for the stem program whereas PI3K inhibits FOXOs tumor suppressor role and mTOR promotes tumorigenic advancement. Particularly GBM and BBC are aggressive cancers that have a stem cell population that makes them difficult to treat and metastatic. We investigate the effects of a combination therapy that inhibits JAK2/STAT3 and PI3K/mTOR output aiming to lower stem cell expression and promote apoptosis. Our collected data indicates that the dual inhibition induced apoptosis, but it also increased the stem cell signature. The findings pave way for the …


Effects Of Global Warming On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In The American Oyster, Sarah B. Nash May 2019

Effects Of Global Warming On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In The American Oyster, Sarah B. Nash

Theses and Dissertations

Global warming due to climate change is predicted to intensify the heat stress in marine and coastal organisms, affecting their development, growth and reproductive functions. In this study. I analyzed gonadal development, heat shock protein 70 (HSP70), nitrotyrosine protein (NTP), dinitrophenyl (DNP) expressions, cellular apoptosis, and coelomic fluid (CF) conditions in American oyster. Oysters were placed in six aquariums and exposed to control (24°C), medium (28°C), and high (32°C) temperatures for one week. Higher temperature significantly decreased the number of eggs and sperm. CF protein concentrations also declined compared to control. In contrast, CF pH and HSP70 expression in gonad …


Social Influences On Vocal Development In A Wild Parrot, Caleb Michael Mand Arellano May 2019

Social Influences On Vocal Development In A Wild Parrot, Caleb Michael Mand Arellano

Theses and Dissertations

The Social Intelligence Hypothesis (SIH) proposes that navigating complex societies requires increased neural processing to monitor shifting relationships. SIH evolutionary focus of brain size variation in adults originally ignored the developmental frameworks leading to increased sociality. I studied the ontogeny of early sibling interactions in wild Green‐rumped Parrotlets (Forpus passerinus) in a Venezuelan population that exhibited large variation in brood size and engaged in elaborate social interactions and complex social learning during nestling development. To test if nests of varying brood sizes exhibit differences in social complexity, I quantified the number and strength of sibling play partnerships, as a proxy …


A Snapshot Of The Age, Growth, And Reproductive Status Of Gray Triggerfish (Balistes Capriscus, Gmelin 1789) On Three Artificial Reefs In The Northwest Gulf Of Mexico, Adam M. Lee May 2019

A Snapshot Of The Age, Growth, And Reproductive Status Of Gray Triggerfish (Balistes Capriscus, Gmelin 1789) On Three Artificial Reefs In The Northwest Gulf Of Mexico, Adam M. Lee

Theses and Dissertations

Age, growth, and reproductive status of gray triggerfish (Balistes capriscus) were identified from 2015-2016 on artificial reefs in the northwest Gulf of Mexico. Individuals ranged from 232-432 mm fork length with and a mean fork length of 319 mm. Individuals from age 0.2 to 5.2 yrs were observed with a weight to length relationship of Wg = 1.1 x -104 x FL2.7 (r2 = 0.94, n = 112), where FL = fork length (mm) and Wg = weight (g). A von Bertalanffy growth equation of Lt = 326(1 - e - 0.9 (t + 1.71)) was calculated irrespective …


Investigating Limitations To Nitrogen Fixation By Leguminous Cover Crops In South Texas, Stephanie L. Kasper May 2019

Investigating Limitations To Nitrogen Fixation By Leguminous Cover Crops In South Texas, Stephanie L. Kasper

Theses and Dissertations

Many farms use leguminous cover crops as a nutrient management strategy to reduce their need for nitrogen fertilizer. Biological nitrogen fixation (BNF) depends on a symbiotic relationship between legumes and nitrogen-fixing rhizobia. Under certain conditions despite inoculation with appropriate rhizobial strains, this symbiosis fails to form. Such failure was observed in a 14-acre winter cover crop trial in the Rio Grande Valley of Texas when three legume species (forage pea, crimson clover, and hairy vetch) produced no signs of nodulation and nitrogen fixation. This study examined nitrogen, phosphorus, moisture, micronutrients and biotic interference as potential causes for the failure and …


Detection Of Heteroplasmic Single Nucleotide Polymorphisms Using Melt Curve Analysis And Dual Labeled Fluorescent Probes, Emily Jezewski Apr 2019

Detection Of Heteroplasmic Single Nucleotide Polymorphisms Using Melt Curve Analysis And Dual Labeled Fluorescent Probes, Emily Jezewski

Honors Theses

Plant mitochondrial genomes are strange – they are unusually large, consist of huge amounts of non-coding DNA, and contain of several overlapping regions throughout the genome. The genome is made of several different sized linear and circular molecules and different mitochondria within a cell will have different pieces of the genome. Even if multiple mitochondria contain the same region of the genome, these sequences can differ by single nucleotide polymorphisms (SNPS). This is known as heteroplasmy. Heteroplasmy has been documented in Arabidopsis thaliana using whole-genome sequencing data. While heteroplasmy is well-documented, its existence in the mitochondrial genome is unexpected and …


Molecular Mechanism Of Neurodegeneration Induced By 4-Nonylphenol, Michelle Alejandra Aranda Jan 2019

Molecular Mechanism Of Neurodegeneration Induced By 4-Nonylphenol, Michelle Alejandra Aranda

Open Access Theses & Dissertations

Neurodegeneration, a progressive loss of nerve cells, occurs in many neurological disorders, including Alzheimer's disease (AD) and Parkinson's diseases (PD), as well as in dementia. The pathogenesis of these diseases is unknown, and recent evidence suggests that environmental factors, which act as endocrine-disrupting compounds (EDCs) could play a significant role in developing the disease process. 4-Nonylphenol (4-NP), an EDC, and a ubiquitous environmental toxin has been shown to affect brain development and may cause neurodegeneration. 4-NP is produced in large quantities in the U.S. and used as raw materials for making detergents, pesticides, plastics, paints, cosmetics, rubber, and other industrial/household …


A Phylogenetic Analysis Of Leptogorgia Virgulata And Leptogorgia Hebes In The Northwestern Gulf Of Mexico, Samantha Silvestri Dec 2018

A Phylogenetic Analysis Of Leptogorgia Virgulata And Leptogorgia Hebes In The Northwestern Gulf Of Mexico, Samantha Silvestri

Theses and Dissertations

The use of genetics in recent years has brought to light the need to reevaluate the classification of many gorgonian octocorals. In 2017, Poliseno et al. conducted a comprehensive, phylogenetic study of the genus Leptogorgia and found that it, too, was in need of taxonomic revision. To expand on their study, 25 samples representing two Leptogorgia species—L virgulata and L. hebes —from the northwestern Gulf of Mexico (GOM) were examined. Ten novel, complete mitochondrial genomes were sequenced using Next Generation sequencing and 24 novel mtMutS sequences were obtained from both species. The phylogenies reconstructed from these sequences indicate the …


Co-Infection Of Zika And Dengue Virus In Aedes Aegypti And Aedes Albopictus Mosquitoes, Felicia Vazquez Dec 2018

Co-Infection Of Zika And Dengue Virus In Aedes Aegypti And Aedes Albopictus Mosquitoes, Felicia Vazquez

Theses and Dissertations

The term co-infection describes an event when multiple pathogens infect a single host. For vector-borne diseases, a vector may become co-infected by feeding either on a single host that has multiple pathogens or feeding multiple hosts, each of which may be infected. Co-infection in non-vector hosts has been shown to influence immune response and eventual outcome of disease, and is likely to have a similar impact on vector species. With multiple vector-borne diseases circulating in South Texas, the potential for co-infection exists. We examined when mosquitoes are infected with one virus and subsequently infected with another. We hypothesized that the …


Arabidopsis Thaliana Transformed With Streptanthus Farnsworthianus Metal Tolerance Protein 1 (Sfmtp1) Or The Native A. Thaliana Metal Tolerance Protein 1 ( Atmtp1) Cdna And The Effects On Sod Enzyme Activity Upon Nickel Treatment, Selina Urbina Fernandez Dec 2018

Arabidopsis Thaliana Transformed With Streptanthus Farnsworthianus Metal Tolerance Protein 1 (Sfmtp1) Or The Native A. Thaliana Metal Tolerance Protein 1 ( Atmtp1) Cdna And The Effects On Sod Enzyme Activity Upon Nickel Treatment, Selina Urbina Fernandez

Theses and Dissertations

Superoxide Dismutase enzyme activity was analyzed in transgenic Arabidopsis thaliana, a non-accumulator weed plant species of the Brassicaceae family, that was transformed with Streptanthus farnsworthianus Metal Tolerance Protein1 (SfMTP1) or A. thaliana Metal Tolerance Protein 1 (AtMTP1 ). The transgenic A. thaliana was exposed to a 12 day treatment of 100 ?M Nickel Acetate in 1/10 X Hoaglands solution in hydroponics. Analysis of Super Oxide Dismutase activity determined that transgenic A. thaliana transformed with the AtMTP1 cDNA and treated with 100 µM Nickel showed a significant increase in Super Oxide Dismutase activity compared to A. thaliana …


Local Delivery Of Mesenchymal Stem Cells Expressing Osteogenesis-Inducing Microrna For Bone Tissue Engineering Applications, Marco Antonio Arriaga Dec 2018

Local Delivery Of Mesenchymal Stem Cells Expressing Osteogenesis-Inducing Microrna For Bone Tissue Engineering Applications, Marco Antonio Arriaga

Theses and Dissertations

Bone is capable of regenerating autonomously when the injury is small (< 2.5 cm), however, large (> 2.5 cm) or insufficiently vascularized defects require intervention to repair. The overall goal of this project is to contribute towards the development of novel strategies to aid bone tissue regeneration by delivering mesenchymal stem cells expressing microRNAs that induce expression of the runt-related transcription factor 2 (RUNX2). It was determined that porous polycaprolactone (PCL) scaffolds fabricated to have a higher surface area to volume ratio (SVR) (> 80) compared to lower SVR (< 80) were hydrolyzed at a higher rate. Scaffolds fabricated with 80 vol. %/300–500 µm porogen were optimal for cell colonization as higher absorbance of metabolized MTT was detected compared to other scaffold types. From the subset of 5 miRNAs tested, miRNA-26a, miRNA-196 and miRNA-218 demonstrated higher upregulation of RUNX2 gene expression and calcium mineralization and thus, are promising candidates for bone tissue regeneration.


Impacts Of Habitat Attributes And Community Gardens On Urban Bird Communities, Samuel Glenn Ortiz Dec 2018

Impacts Of Habitat Attributes And Community Gardens On Urban Bird Communities, Samuel Glenn Ortiz

Theses and Dissertations

The Rio Grande Valley of Southern Texas is a major agricultural region yet has some of the highest hunger rates in the USA. Urbanization and agriculture affect biodiversity, which is well studied, but little is known about how agriculture affects biodiversity in urban areas. We investigated how different urban attributes, including those related to urban farming, impact bird communities in Brownsville and Harlingen, TX, and compared sites that have community gardens to those that do not. To study three key urban habitat characteristics, we identified sites that exhibited all possible combinations of these factors, quantified land cover classes related to …


Effects Of Invasive Nilgai Antelope (Boselaphus Tragocamelus ) Browsing On Black Mangrove (Avicennia Germinans) In South Texas: A Study On Microenvironmental, Physiological, Structural, And Reproductive Parameters, Tianna Picquet Dec 2018

Effects Of Invasive Nilgai Antelope (Boselaphus Tragocamelus ) Browsing On Black Mangrove (Avicennia Germinans) In South Texas: A Study On Microenvironmental, Physiological, Structural, And Reproductive Parameters, Tianna Picquet

Theses and Dissertations

Mangroves are important for coastal systems because they provide habitat for fish and bird species, mitigate erosion, and create an area for carbon sequestration. Along the Gulf of Mexico, at the southern tip of Texas, recent observations have shown that A. germinans stands (the dominant species in Texas) are being browsed on by invasive nilgai antelope (Boselaphus tragocamelus). The antelope were introduce to the south Texas region via King Ranch in the 1930’s and have since significantly increased in population and distribution. Previously thought to be grazers, B. tragocamelus were captured on camera utilizing A. germinans as a …


Environmental Conditions In San Martin Lake: Effects Of Eutrophication In An Estuary Associated With The Laguna Madre, Wendy L. Rogers Aug 2018

Environmental Conditions In San Martin Lake: Effects Of Eutrophication In An Estuary Associated With The Laguna Madre, Wendy L. Rogers

Theses and Dissertations

San Martin Lake is a shallow water Estuary in the lower Laguna Madre off the Port of Brownsville Shipping channel. It is influenced both by incoming tides and waste water runoff both from local farms and the Brownsville water treatment plants. The resulting mixture of eutrophic water and incoming sea water creates the perfect mix for a potential algal bloom. This study looks at the nutrient levels and environmental conditions in the main basin of the estuary to establish baseline levels and to observe the rate of nutrient clearing being accomplished in this environment. As sport recreation in the area …


Embryology And Wing Development In A Dragonfly (Tramea Onusta), Valeria M. Casas Aug 2018

Embryology And Wing Development In A Dragonfly (Tramea Onusta), Valeria M. Casas

Theses and Dissertations

Most phylogenetic research within the insect phylogeny is focused on higher order taxons. Therefore, to better understand insect wing and flight origin, genetic studies on more primitive insect orders is necessary. Odonata, the order including dragonflies, is one of the earliest insect taxa to develop wings. Hox genes are highly conserved regulatory genes involved in embryonic development of organisms. Hox gene expression studies in insects allow improved insight of body plan development including wings. Embryonic development of dragonfly, Tramea onusta, was analyzed at various developmental stages. Developmental genes Antennapedia, Distal-less, Ultrabithorax, abdominal-A, Abdominal-B, engrailed, Cadual, engrailed 2, Wingless, nubbin, …


Nannochloris Sp. And Oocystis Sp. Algae Exposed To Osmotic Stress For Increased Lipid Production For Use In Biofuels, Laura M. Chavez Aug 2018

Nannochloris Sp. And Oocystis Sp. Algae Exposed To Osmotic Stress For Increased Lipid Production For Use In Biofuels, Laura M. Chavez

Theses and Dissertations

Algal biofuel research is important due to the potential need for replacement of non-renewable fossil fuels and a changing global climate. Under stress, algal cells tend to increase neutral lipid production, which are a suitable source for biofuels. The goal of this study was to subject Nannochloris sp.. and Oocystis sp. algal cells to osmotic stress by modifying sucrose and salinity levels in different treatment medias.

The treatment containing the lowest salinity (15 ppt) and no sucrose yielded the highest lipid fluorescence/cell in Nannochloris sp.. cells (0.00142 ± 0.00044) on day 2 while the treatment containing highest salinity (35ppt) …


Questing Activity Of Cattle Fever Tick Larvae, Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae): Environmental Influences And Implications For Control In South Texas, Brenda Leal Aug 2018

Questing Activity Of Cattle Fever Tick Larvae, Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae): Environmental Influences And Implications For Control In South Texas, Brenda Leal

Theses and Dissertations

Questing ticks ascend stems, leaves, or rocks, extend their front legs, and wait poised for attachment to a passing host. Ixodid ticks have four developmental stages. Because ticks detach and molt between stages most ticks require three separate hosts to complete their lifecycle. Three-host ticks quest for a new host between each stage, whereas a few specialist tick species remain on and thus require only a single host. These one-host ticks only quest for hosts as larvae. As much as 90% of the life cycle may consist of questing when hosts are scarce. Most of the literature on questing relates …


Survey Assessment Of Community Knowledge And Prevention Of Chagas Disease And Its Vector In Hidalgo And Cameron Counties, Adam Dennis Wiejaczka Aug 2018

Survey Assessment Of Community Knowledge And Prevention Of Chagas Disease And Its Vector In Hidalgo And Cameron Counties, Adam Dennis Wiejaczka

Theses and Dissertations

Chagas disease, caused by the parasite Trypanosoma cruzi, kills thousands of people annually and is the dominant cause of infectious myocarditis worldwide. Kissing bugs are vectors that carry T. cruzi . and are found in the Lower Rio Grande Valley (LRGV). There is no vaccination nor cure for Chagas. The best mechanism of prevention is to control vector infestations. Little research is available regarding the level of understanding local communities have about Chagas.

Our goal was to test the knowledge of several communities in the LRGV on Chagas disease. Our hypothesis states that local communities do not have sufficient …


Trichomonas Vaginalis Cytoadherence Is Modulated By Oxidative Stress, Magali Ayala Jul 2018

Trichomonas Vaginalis Cytoadherence Is Modulated By Oxidative Stress, Magali Ayala

Theses and Dissertations

The adherence of Trichomonas vaginalis to the human urogenital tract is a prerequisite for the pathogenesis of the infection. This multifactorial process is modulated by environmental factors such as iron, estrogen, temperature and pH and specific receptor/ligand interactions. During natural infections, the anaerobe T. vaginalis is exposed to oxygen resulting in oxidative stress. This environmental change may alter trichomonad cytoadherence to the ectocervical tissue. Therefore, it was hypothesized that changes in the redox status of T. vaginalis may modulate cytoadherence levels. Results showed that oxidative stress reduces levels of trichomonad cytoadherence to HeLa cells by > 50% when exposed to 150 …