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Cellular And Molecular Alterations Associated With Ovarian And Renal Cancer Pathophysiology, Ravneet Kaur Chhabra

USF Tampa Graduate Theses and Dissertations

Elucidating molecular alterations underlying tumor development and chemoresistance are critical to expand our understanding of the disease pathophysiology. This dissertation is focused on analyzing the cellular and molecular alterations associated with LPA-induced chemoresistance in clear cell renal cell carcinoma (ccRCC) cells and chronic iron-induced deregulation of miRNA expression in fallopian tube secretory epithelial cells (FTSECs).

Kidney cancer is one of the ten most common cancers worldwide with <15% survival rate at advanced stage (American Cancer Society). ccRCC is the most common type of kidney cancer and is described as a metabolic disease characterized by deregulated lipid metabolism leading to increased intracellular lipid droplets [9, 10]. The current molecular-targeted treatment strategies involve VEGF/VEGFR and mTOR inhibition [9, 12]. However, there are limitations to these approaches leading to the reduced efficacy and/or increased resistance in ccRCC cells [13, 14]. Therefore, it is important to decipher the factors involved in compromising the chemosensitivity in these cells.

Lysophosphatidic acid (LPA), a bioactive phospholipid, was previously reported to increase resistance against Sunitinib (VEGFR/PDGFR inhibitor) in ccRCC cells and to increase migration and invasion in various tumors [15-17]. In Chapter 3 of …

Investigating The Proteinaceous Regulome Of The Acinetobacter Baumannii, Leila G. Casella

USF Tampa Graduate Theses and Dissertations

Acinetobacter baumannii is an opportunistic pathogen that overtime has evolved into one of the most problematic pathogens due to its ability to overcome antibiotic pressures and harshly environments in the host and hospital environments. In this context, its genomic evolution due to its capacity to acquire genes that contribute to its pathogenic and antibiotic resistance nature has been the subject of research in the last decades providing with the identification of several proteins aiding in the process of pathogenicity. Although these findings have contributed to our understanding of A. baumannii pathogenic traits, the regulatory network that control their expression are …

Modeling Potential Chemical Environments: Implications For Astrobiology, Brian Craig Szenay

USF Tampa Graduate Theses and Dissertations

Modeling chemical environments is an important step to understanding the diversity of prebiotic systems that may have formed on the early earth or potentially can occur on other worlds. By using the modern Earth as a test case, these models predict scenarios with systems more conducive to the formation of the organic molecules that are important to life. Here we use the equilibrium thermodynamic modeling program HSC Chem to investigate prebiotic environments. This program uses the raw material that the user inputs into the system in order to calculate the change in amounts of chemical species forming as a function …

Heme Biosynthesis: Structure-Activity Studies Of Murine Ferrochelatase, Zhen Shi

USF Tampa Graduate Theses and Dissertations

Ferrochelatase catalyzes the terminal step of heme biosynthesis by inserting ferrous iron into protoporphyrin IX. The current study is aimed at understanding the structural basis of porphyrin binding and distortion in ferrochelatase-catalyzed reaction by functional analysis of a highly conserved active site loop motif. The loop was shown to contact bound porphyrin based on crystallographic and molecular modelling observations, and its role in murine ferrochelatase was assessed by random mutagenesis and steady-state kinetic analysis. To overcome the limitations of conventional kinetic assay methods for ferrochelatase, a continuous assay was developed by monitoring porphyrin fluorescence decrease using natural substrates ferrous iron …

Mathematical Model Of Arsenic Adsorption In A Modified Zeolite / Microfiltration System, Miles B. Beamguard

USF Tampa Graduate Theses and Dissertations

Carcinogenic health concerns over arsenic in drinking water caused the USEPA to reduce the maximum contaminant level (MCL) from 50 to 10 ppb, effective on January 23, 2006. This has forced many smaller utilities into expensive treatment or discontinuation of water distribution. Researchers throughout the world are working to develop an inexpensive method for arsenic removal to meet this MCL. Aluminum silicates, or zeolites, are naturally occurring ionic sorbents. Modification of a zeolite may enhance adsorption capacities and ion selectivity. This research investigates the arsenic adsorption capacities of a modified Chabazite. This adsorption, coupled with a hollow fiber, microfiltration membrane …

Saharan Dust And Phosphatic Fidelity: A Three Dimensional Biogeochemical Model Of Trichodesmium On The West Florida Shelf, Jason M. Lenes

USF Tampa Graduate Theses and Dissertations

The availability of iron within the surface waters of the broad, oligotrophic West Florida shelf (WFS) controls periodic blooms of the pelagic marine cyanobacterium Trichodesmium. Summer delivery of iron (Fe), in the form of Saharan dust, alleviates this growth constraint, shifting limitation to the efficiency of phosphorus (P) cycles. Florida's rivers drain Miocene phosphorus deposits to supply the WFS with freshwater nutrient supplies at molar dissolved inorganic nitrogen/phosphate (DIN/PO4) ratios of less than 6. These diazotrophs draw upon ubiquitous stocks of dissolved nitrogen gas, once stimulated by Fe-deposition within P-replete waters of the West Florida shelf. An extensive in situ …

Influence Of Solution And Surface Chemistry On Yttrium And Rare Earth Element Sorption, Kelly Ann Quinn

USF Tampa Graduate Theses and Dissertations

The sorption behavior of yttrium and the rare earth elements (YREEs) was investigated using a variety of hydroxide precipitates over a range of solution conditions. Experiments with amorphous hydroxides of Al, Ga, and In were conducted at constant pH (~6.0) and constant ionic strength (I = 0.01 M), while YREE sorption by amorphous ferric hydroxide was examined over a range of ionic strength (0.01 M <̲ I <̲ 0.09 M), pH (3.9 <̲ pH <̲ 7.1), carbonate concentration (0 M <̲ [CO32-]T <̲ 150 micro-M), and temperature (10°C <̲ T <̲ 40°C). Sorption results were quantified via distribution coefficients, expressed as ratios of YREE concentrations between the solid and the solution, and normalized to concentrations of the sorptive solid substrate. Distribution coefficient patterns for Al, Ga, and In hydroxides were well correlated with the pattern for YREE hydrolysis.

In contrast, amorphous ferric hydroxide developed a distinct pattern that was different than those for Al, Ga, and In precipitates but similar to the pattern predicted for natural marine particles. YREE sorption was shown to …