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The Effect Of Manganese (Mn) On Cell Proliferation And Migration In The Michigan Cancer Foundation-7 (Mcf-7) Human Breast Cancer Cell Line In Vitro, Justin Lloyd Wendel

Theses and Dissertations

Manganese (Mn) is a common environmental element necessary for mammalian physiological processes. However, dietary excess or deficiency can lead to detrimental health effects. Therefore, I investigated the effect Mn has on breast cancer progression in vitro. Utilizing MCF-7 breast cancer cells an MTT assay was performed to identify proliferative potential. After 5 days, results showed 100 nM manganese chloride (MnCl2) had a significant (p<0.01) increase in cell number over control. Using a scratch wound-healing assay, 100 nM MnCl2 was found to increase cellular motility as well as induce a possible change in morphology and cytoskeletal organization. Given Mn was shown to localize in the mitochondrial, we investigated Mn-induced ROS expression. 500 nM Mn significantly decreased (p<0.05) ROS levels. Collectively, I provide evidence that Mn may potentially drive less aggressive cancer cells towards a more invasive phenotype.

South Padre Island Beach Management: Assessment Of Dune Restoration, Shelby Rose Bessette

Theses and Dissertations

Dune restoration is a common method of increasing coastal resilience. A dune restoration program was initiated by the City of South Padre Island, TX in 2010 consisting primarily of plantings of Sea Oats, Uniola paniculata, and Bitter Panicum, Panicum amarum and has continued approximately annually thereafter. These restoration efforts were evaluated in this study by comparing dune ecological structure and function among reference sites and restoration plots ranging in age from 2 to 5 years. Plant and animal communities were examined using a combination of quadrat sampling, funnel traps, pit-falls and sweep nets. Soil organic content and soil electric …

Characterizing Mesophotic Reef Fish Communities At Five South Texas Relic Coral-Algal Banks, Linda Marie Jordan

Theses and Dissertations

The South Texas Banks are a mesophotic coral ecosystem (30-150m deep). Understanding the community structure, biodiversity and, geographic connectivity of the South Texas Banks is essential with increasing threats from climate change, ocean acidification, invasive species, and pollution. In this study, a remotely operated vehicle (ROV) was used to examine the fish communities at five of the South Texas Banks: Big Adam, Hospital, Mysterious, North Hospital, and Southern. Reef fish were identified to the lowest possible taxon and enumerated from ROV transect video footage. A total of 3,838 demersal and pelagic fishes were recorded representing 61 species in 22 families …

Microwire Regenerative Peripheral Nerve Interfaces With Wireless Recording And Stimulation Capabilities, Ali Ajam

Theses and Dissertations

A scalable microwire peripheral nerve interface was developed, which interacted with regenerated peripheral nerves in microchannel scaffolds. Neural interface technologies are envisioned to facilitate direct connections between the nervous system and external technologies such as limb prosthetics or data acquisition systems for further processing. Presented here is an animal study using a handcrafted microwire regenerative peripheral nerve interface, a novel neural interface device for communicating with peripheral nerves. The neural interface studies using animal models are crucial in the evaluation of efficacy and safety of implantable medical devices before their use in clinical studies.16-electrode microwire microchannel scaffolds were developed for …

Relationships Between Texas Tortoise Carapace Length, Home Range Size, And Habitat Selection At Sites With Invasive Grass, Kiley V. Briggs

Theses and Dissertations

Invasive grasses in south Texas have the potential to negatively impact the threatened Texas tortoise (Gopherus berlandieri) by reducing the availability of preferred foods (forbs) and may cause tortoises to travel farther, lead to reduced carapace length, and reduce the availability of refugia from heat stress. I used compositional analysis, regression, and ANOVA to explore relationships between invasive grasses and habitat use, home range size, and carapace length, as well as compared daily maximum temperatures between tussocks of an invasive and native grass. Forbs were ranked higher in use over invasive grasses in compositional analysis, but not strongly so (p …

Characterizing Benthic Invertebrate Communities At Five South Texas Banks, Maria T. Cooksey

Theses and Dissertations

On the continental shelf off the coast of South Texas lie a series of hardbottom structures known as the South Texas Banks, which provide critical habitat for benthic organisms and pelagic fish species. The depth of the banks, a persistent nepheloid layer, and strong currents have hindered efforts to collect quantitative data on what inhabits the rocky outcrops and relic coral-algal reefs. Using a remotely operated vehicle, video data from five of the banks were collected in order to characterize the benthic communities. Southern and North Hospital Banks were found to be the most diverse of the studied South Texas …

Apoptotic And Necrotizing Mechanisms Of Recombinant Panton-Valentine Leukocidin In Thp1 Monocytes., Heriberto Deleon Iii

Theses and Dissertations

The Panton-Valentine Leukocidin (PVL) is a highly specialized bacterial exotoxin produced by Staphylococcus aureus. The increased degree of invasiveness of community associated methicillin resistant Staphylococcus aureus (CAMRSA) has been attributed to the relatively high rates of PVL produced by the pathogen, thus increasing pathogenicity and virulence. The increased rates of PVL encoding CAMRSA infections have been correlated with increased rates of necrotizing fasciitis, invasive osteomyelitis and invasive necrotizing pneumococcal infections. Previous research as revealed that PVL has the ability to induce apoptosis at low concentration (5nM-10nM) and necrosis (50-100nM) at high concentrations, with little detail on the mechanism of initiation. …

Jatropha Curcas Protoplast Isolation And Inhibitory Effects Of Culture, Christopher S. Lukaszewski

Theses and Dissertations

Improvement on the sub-tropical plant Jatropha curcas may increase the use of this drought tolerant oilseed crop for the production of biodiesel. One of the methods for enhancing a species is through genetic manipulation of the protoplast. Isolating protoplasts is challenging and culturing has many obstacles similar to those seen in tissue culture, such as oxidative browning. Successful isolation of J. curcas leaf protoplasts resulted in an average of 3.23 x 106 viable protoplasts/mL. However, protoplasts diminished within 2 days after culturing. A review of the potential solutions used for overcoming the inhibitory effects of culture may reveal further insight …

Handcrafted Electrocorticography Electrodes For A Rodent Neural Activity, Nishat Tasnim

Theses and Dissertations

Electrocorticography (ECoG) is a minimally invasive neural recording method that has been extensively used for neuroscience applications. Although many neural recording methods exist, ECoG provides a combination of stability, high spatial and temporal resolution with chronic and mobile capabilities. This paper presents an animal study using a low cost and simple handcrafted ECoG electrode that is made of commercially accessible materials. The study is performed on a Lewis rat implanted with a handcrafted 32-channel non-penetrative ECoG electrode covering an area of 3 x 3 mm 2 on the cortical surface. The ECoG electrodes were placed on the motor and somatosensory …

The Acute Effects Of Aerobic Exercise With Blood Flow Restriction Cuffs On Arterial Compliance In Males And Females, Maria M. Gonzalez

Theses and Dissertations

RESULTS: Significant condition*gender interactions found in in SBP (p<.05), PR (p<.01), SVR (p<.01), SpO2 (p<.05), PWV carotid to femoral (p<.03), and PWV femoral to distal (p<.02). Significant condition*time interactions were found in SBP (p<.01), DBP (p<.01), MAP (p<.01), SV (p<.01), CO (p<.01), SVR (p<.01), TVI (p<.01), HR (p<.01), and SAE (p<.01). Significant condition main effects were found in SBP (p<.02), DBP (p<.03), PR (p<.03), SV (p<.01), CO (p=.01), SVR (p<.01), TVI (p<.01), HR (p<.01), and SAE (p<.03) as well as a condition trend in PWV femoral to distal (p=.06). Significant time main effects were found in SBP (p<.01), MAP (p<.04), PP (p<.01), PR (p<.01), CO (p<.01), SVR (p<.01), TVI (p<.01), HR (p<.01), SpO2 (p<.01), LAE (p<.03), and PWV femoral to distal (p<.01).

CONCLUSION: The 60 min session at a moderate aerobic intensity might have the potential to improve arterial elasticity more than a 20 min BFR session.

Opinion Formation About Childhood Immunization And Disease Spread On Networks, Shan Shan Zhao

Theses and Dissertations

People are physically and socially connected with each other. Those connections between people represent two, probably overlapping, networks: biological networks, through which physical contacts occur, or social network, through which information diffuse. In my thesis research, I am trying to answer that question in the context of pediatric disease spread on the biological network between households as well as within them and its relationship with information sharing on the social network of households (parents in that case) via "Information Cascades." I mainly focus on the Erdos-Renyi network model. In particular, I use two different but overlapping Erdos-Renyi networks for the …

Validating Side Scan Sonar As A Fish Survey Tool, Michael A. Bollinger

Theses and Dissertations

Hydroacoustic methods can be used to answer a variety of questions regarding fish populations and behavior. In this study, side scan sonar methodology was developed to quantify abundance and biomass and compared to established visual observation methods on SCUBA over artificial reef structures in the western Gulf of Mexico. Side scan sonar methods were equivalent to SCUBA surveys for measuring fish abundance over the same reef areas, however, abundances were significantly higher when the larger area sampled by side scan was utilized. Side scan sonar methods were also more time efficient than SCUBA, ROV and long line fishing methods (66.7%, …

Examination Of The Chagas Disease Vector, Triatoma Gerstackeri, In The Lower Rio Grande Valley, Alfredo Flores

Theses and Dissertations

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, which is carried by an insect vector of the family Reduviidae, and of the subfamily Triatomina. The species Triatoma gerstaeckeri is identified as the primary vector of T. cruzi within the Rio Grande Valley. Species of Triatoma gerstaeckeri were trapped in La Sal del Rey National Refuge in 2012 and 2013.

Data indicates a seasonal dispersal pattern of activity for T. gerstaeckeri. Optimal time of capture was between 1-2 hours after sunset. Different methods were utilized to determine the best combination of lures. Results indicate that the UV-light alone is …

Decomposition And Nitrogen Dynamics Of Turtle Grass (Thalassia Testudinum) In A Subtropical Estuarine System, Monica Delgado

Theses and Dissertations

Seagrass beds are pivotal in the functioning of coastal ecosystems in terms of productivity, organic matter turnover and nutrient cycling. Aiming to document decay and nitrogen (N) dynamics of turtle grass (Thalassia testudinum) in a subtropical estuarine system, decomposition patterns of leaves and rhizomes were characterized and compared. Nitrogen usage during decomposition of tissues, and of live tissues and epiphytes growing on live leaves, was also quantified and compared. Stable isotope ratios allowed tracing N within the seagrass bed, following N incorporation into seagrass tissues from the surrounding media (water, sediment). Leaves had a higher N content and decomposed at …

Activation Of Microglia In The Rotenone Lymnaea Stagnalis Model Of Parkinson's Disease, Xiomara Galvan

Theses and Dissertations

Parkinson’s disease (PD) is the most common irreversible neurodegenerative movement disorder affecting approximately ten million people worldwide. In the central nervous system (CNS), PD is known by the selective loss of Dopamine (DA) cells of the substantia nigra pars compacta. Although the disease has been very widely studied, the underlying mechanisms are not yet understood. Several hypotheses have arisen as result of injury of the mitochondria, some experiments include microglia activation, microtubule damage, and reactive oxidative species, which all result in the death of DA cells. The theory of microglia activation upon inflammation was explored in this study. Using the …

A Handcrafted Multi-Branch Nerve Scaffold For In Vivo Peripheral Nerve Regeneration, Ridwan Fayaz Hossain

Theses and Dissertations

Arm and leg peripheral nerve injuries contribute largely to functional disability. These injuries seldom affect a single-line nerve; rather the injury goes beyond and disrupts the nerve tissue across multiple nerve paths. Here we investigate handcrafted PDMS based multi-branch nerve guidance conduit, which addresses this crucial branching from the sciatic nerve to aid with the regeneration to their appropriate distal targets. The design concept of the developed multiple branch nerve scaffolds is not specific for the sciatic nerve but can be modified for general use of all peripheral nerves and additional applications. Microchannels are also fabricated into a device in …

Balanus Eburneus (Crustacea: Cirripedia) As A Potential Indicator Of Estuarine System Recovery In South Texas: A Study Of Recruitment, Growth And Stable Isotopes, Crystal Martinez

Theses and Dissertations

Population characteristics of the barnacle Balanus eburneus were analyzed with the purpose of exploring its potential use as a discriminating indicator among sites exhibiting different disturbances or stages of recovery. The study was conducted from May 2012 to May 2013 at four estuaries in the Lower Laguna Madre, TX including a) Bahia Grande, currently under restoration and divided into Bahia Grande North and Bahia Grande South, b) San Martin Lake, which receives runoff water and c) South Bay, a relatively undisturbed reference estuary. In general, similar barnacle recruitment and growth trends in Bahia Grande South and South Bay were explained …

Effects Of Shrub Encroachment And Removal On South Texas Coastal Prairie Flora, Parker Alex Watson

Theses and Dissertations

Watson, Parker Alex, Effects of shrub encroachment and removal on South Texas coastal prairie flora. Master of Science, December, 2015. 60 pages, 14 tables, 11 figures, 47 references, 5 appendices. Native-invasive honey mesquite (Prosopis glandulosa) and huisache (Acacia farnesiana) are aggressively encroaching onto South Texas coastal prairies, outcompeting Gulf cordgrass (Spartina spartinae) and associated prairie vegetation with potential legacy effects on the landscape. To measure conditions in the presence of shrubs, data loggers were installed for 16 mos in shrub understories and grass cover to monitor light, soil and air temperatures. Vegetation and canopy surveys were also conducted to evaluate …

Comparing Reproductive Capacity Of Nearshore And Offshore Red Snapper, Lutjanus Campechanus, On Artificial Reefs In The Western Gulf Of Mexico, Ricky J. Alexander

Theses and Dissertations

Red snapper collected quarterly from four artificial reefs in south Texas were examined to compare total length, total weight, age, and the proportion of male to female red snapper, calculate gonadosomatic index values, batch fecundity, annual spawning frequency, and annual fecundity, and estimate size and age at maturity. Spawning occurred from April to September, with most active spawning observed in June (58%). Despite larger red snapper producing more eggs, and fish being larger offshore, most active spawning (68%) and egg production (74%) was observed nearshore. Female red snapper reached 50% maturity (L50) between 350-550 mm, and L75 by 600 mm. …

Air-Water Gas Exchange And The Carbon Cycle Of Green Bay, Lake Michigan, James Waples

Theses and Dissertations

The purpose of this study was to constrain estimates of the kinetics of gas transfer across the air-water interface as well as quantify the net flux of carbon between southern Green Bay (1635 km²) and the atmosphere.

In 1994 and 1995, over 3500 measurements of surface water CH₄ and CO₂ were made using a continuous sample disk equilibrator. Estimates of CH₄ flux from southern Green Bay to the atmosphere based on air-water concentration gradients, shear corrected wind speeds and the U/K (wind speed/transfer coefficient) relationship of Broecker et al. (1978) agreed to within ~10% of …