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Zinc-Mediated Regulatory Function Of Psd-95 On Nmdar At Post-Synapses, Luis F. Acosta

Theses and Dissertations

Postsynaptic density-95 (PSD-95) is a membrane-associated guanylate kinase that mediates localization of receptors in the excitatory postsynaptic density. It has been reported that PSD-95 mediates postsynaptic localization of NMDA receptors and anchors postsynaptic AMPAR receptors mainly through its postsynaptic membrane targeting by its N-terminal palmitoylation. Recent studies have shown that Ca2+/calmodulin blocks palmitoylation of PSD-95 by binding at the N-terminus of PSD-95, which promotes dissociation of PSD-95 from the postsynaptic membrane and causes loss of surface AMPARs in cultured neurons. Another metal ion zinc is found in various areas of the brain. As an endogenous neuromodulator, zinc plays a role …

Targeting Protein Synthesis In Clostridioides Difficile To Develop Antimicrobial Candidate, Elvira L. Alanis

Theses and Dissertations

Clostridioides difficile is a gram positive, spore forming, obligate anaerobic bacterium that causes Clostridioides difficile infection (CDI) which can result in pseudomembranous colitis and toxic megacolon. In the case of this research a focus on Protein synthesis is made since it is an essential metabolic process and is a validated target for antibiotics. Protein synthesis begins with Initiation which includes the three translation initiation factors. Through the NMR chemical shift assignments, the IF1 structure was determined, and it was found to be composed of a short α helix and five β helixes. A peptide was designed after the short α …

The Potential Impact Of Climate Change On The Distributions Of Eleutherodactylus Cystignathoides And E. Planirostris (Anura: Eleutherodactylidae), Rebecca T. Chastain

Theses and Dissertations

Climate change is inducing changes in the distributions of many species, causing range shifts and habitat loss as well as facilitating invasions. It is a broad contributor to global amphibian decline, already causing mass extinctions and extirpations of amphibian populations, a phenomenon which is expected to continue. The understudied direct-developing frog Eleutherodactylus cystignathoides is a notable outlier, having rapidly expanded its distribution in recent years. This is of particular interest given that other eleutherodactylids, such as E. coqui and E. planirostris, have already shown propensity for rapid dispersal and invasion. Originally found in the southernmost tip of …

Effects Of Tributyltin Exposure On 8-Ohdg And Dsdna Expressions, Oxidative And Nitrative Stress In The American Oyster, Crassostrea Virginica, Mohan Kumar Dash

Theses and Dissertations

Environmental pollution increases due to anthropogenic activities. Different types of pollutants and/or chemicals impair growth, reproduction and development in aquatic organisms. Tributyltin (TBT, an organotin compound) is a tremendously toxic substance which widely uses as antifouling paints used in boats, hulls, and ships. The toxic effect of TBT is well documented in teleost species. The American oyster (Crassostrea virginica) is an ideal shellfish species to study on TBT exposure DNA lesion and oxidative/nitrative stress. In this study, the effects of TBT on 8’-hyrodxy-2’-deoxyguanosine (8-OHdG, a molecular marker), dsDNA, dinitrophenyl protein …

Harvester Ant (Pogonomyrmex Sp.) Seed Preferences And Distribution In A Suburban Setting, Lilly V. Elliott

Theses and Dissertations

Harvester ants (Pogonomyrmex sp.) are omnivorous ants native to Texas and are the main food source for the threatened Texas Horned Lizard (Phrynosoma cornutum). Little research has been conducted on harvester ants in the Lower Rio Grande Valley (LRGV) and their interactions with their environment. For this purpose, a variety of experiments were conducted to better understand these interactions and preferences. In CHAPTER I, suburban harvester ants were exposed commonly used cover crop seeds in the LRGV and inoculated seeds via seed depots over the course of 24 hours. We found that harvester ants do …

Postprandial Hemodynamics In Hispanics With And Without A Family History Of Type 2 Diabetes, Gabriel Alejandro Figueroa

Theses and Dissertations

Hispanics of the Rio Grande Valley (RGV) have the highest rates of obesity and type 2 diabetes (T2D) in the country, conditions often associated with cardiovascular disease and increased mortality. This study investigated the physiological factors affecting postprandial hemodynamic responses differently between FH+ and FH- groups. Thirty-one healthy Hispanic individuals volunteered in this study. Overall, FH+ individuals had higher pressures at rest compared to FH-, However, these differences were not statistically significant. When controlling for blood chemistries such as blood glucose, cholesterol, lipoproteins, and triglycerides, family history appears to have no effect on fasted or postprandial hemodynamics and pulse wave …

Structures And Regulations Of Translation Initiation Factors In Pseudomonas Aeruginosa Protein Biosynthesis To Develop New Potential Antimicrobial Agents, Nicolette Valdez

Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative, multidrug resistant bacterium that has been recognized as the prominent cause of nosocomial infections. Untreated acute and chronic infections associated with P. aeruginosa can develop into other diseases such as pneumonia, otitis externa, and osteomyelitis. P. aeruginosa infections commonly affect immunocompromised individuals such as cystic fibrosis, cancer, and burn patients. The misuse and overuse of antibiotics has contributed to the increased antibiotic resistance in P. aeruginosa and thus has led to an unmet need for discovery of novel antibiotic candidates. Protein biosynthesis is an essential metabolic process occurring in all bacteria and a validated target …

Comparing Various Physiological System Adaptations Following 8 Weeks Of Resistance Training With Or Without Bfr In Older Males, Ricardo Parra

Theses and Dissertations

PURPOSE: The purpose of this study was to compare the effects of 8 weeks of resistance exercise training with and without BFR on: 1), arterial elasticity and hemodynamics (e.g., blood pressure and resting heart rate), 2) muscular force production (e.g., maximal voluntary contraction, force production, electromyography, and estimated one-repetition maximum) in males between the 50 to 70 years of age.

RESULTS: Significant condition difference for reflection magnitude occurred in BFR group (p < 0.05). Significant time*condition effect occurred in Leg Press 1RM, Leg Extension 1RM, Leg Curl 1RM, Chest Press 1RM, and Shoulder Press 1RM (p < 0.05). Significant condition* time interaction occurred for Isokinetic Leg Extension Test (60°/s) (p < 0.05). A significant time*condition interaction occurred during Maximal Voluntary Contraction (MVC) – Root Mean Square for both vastus medialis and vastus lateralis (p < 0.05). A significant time main effect occurred in the BFR group for the amplitude mean of the MVC in the vastus medialis and vastus lateralis (p < 0.05). A significant time main effect occurred for median frequency of the MVC (p < 0.05). A significant difference in Estimated Visceral Adipose Tissue occurred in the BFR group (p < 0.05). A significant condition*time interaction occurred in arm fat percentage (p < 0.05). The BFR group had significantly less fat tissue (%) in the left arm (p < 0.01) and in the right arm (p = 0.04). A significant time*main effect occurred in the total lean tissue for the left side of the body (p = 0.04).

CONCLUSION: Using BFR resistance training at a low intensity can achieve similar adaptations seen at high intensities while reducing the risk of injury that comes with heavier loads.

Nanostructured Materials For Biomedical Applications, Silverio Lopez

Theses and Dissertations

Nanotechnology has been used in an increasing number of applications in biochemistry and molecular biology. Compared to bulk materials, nanoscale materials offer a variety of advantages in applications due to an increased surface-to-volume ratio of the reactants. The unique properties of nanostructured materials and their properties such as stability, reactivity, magnetic response, pressure discharge performance and biocompatibility depend on particle size and shape. This work focuses on a nanoenergetic material composed of Aluminum (Al), Copper II oxide (CuO), and Iodine (I) pentoxide (I2O5), and the biomedical application of nanoscale dextran-coated magnetite (Fe3O4), which was produced using microfluidics to tune particle …

Assessing The Effects Of Levonorgestrel (Lng) On Neural Differentiation In The Developing Hypothalamus Using The Zebrafish (Danio Rerio) As A Model, Gabriella Hinojosa

Theses and Dissertations

Neurogenesis is a critical component of fetal neurodevelopment consisting of: migration, proliferation and differentiation. Health concerns from anxiety to reproductive issues have been linked to alterations of neurogenesis processes. Endocrine disrupting chemicals (EDCs) can mimic hormones vital to this process, potentially adversely affecting the susceptible fetal brain. One EDC, Levonorgestrel (LNG), is a testosterone-like progestin used in birth control methods that has a high bioavailability and long half-life. Using zebrafish embryos as a model, this lab previously discovered that an environmentally relevant LNG dose (5 ng/L) significantly increased anxiety behaviors. The hypothalamus is responsible for the development …

Exploring Dna Compaction Via Bacillus Subtilis Parb Protein By Single Molecule Investigation, Miranda L. Molina

Theses and Dissertations

Faithful chromosome segregation involves ParB, a DNA-binding and compacting protein that specifically recognizes parS DNA sites near the replication origin. ParB spreads 10-20 kb from parS sites, which recruitments additional ParB molecules to neighboring DNA, forming higher-order nucleoprotein complexes. ParB is also a novel CTPase enzyme and hydrolyses CTP to self-dimerization and create a clamp that slides along DNA. To understand the roles of CTP in Bacillus subtilis ParB (BsParB), we purified wild type ParB (BsParB (WT)) and recombinant ParB (BsParB(R80A)) mutant. BsParB(R80A) was known to prevent CTP binding and not compact DNA. Proteins N- and C-terminally appended with a …