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Quantitative Analysis And Imaging-Based Insights Into The Characteristics And Mechanisms Of Yeast Pattern Formation, Lin Chen

Dissertations and Theses (Open Access)

Biofilm formation is a common lifestyle adapted by bacteria and fungi in response to various environmental stresses. Bacterial and fungal biofilms adhering to medical devices convey resistance to antibiotics or biocides, causing high rates of clinical infections. Microorganisms are protected from harsh environmental conditions by reduced stress penetration through the complex biofilm architecture with distinct patterns. Although the molecular regulations of surface patterning have been well characterized in bacteria, the mechanisms underlying the complex pattern formation in eukaryotic biofilms remain unclear.

This dissertation aims to investigate the salient features of robust colony expansion in yeast biofilms and the processes driving …

Functions Of The Homeobox Gene Dlx4 In Controlling Inflammatory Signaling And Metastasis Of Epithelial Ovarian Cancer, Dhwani Haria

Dissertations and Theses (Open Access)

Epithelial ovarian cancer (EOC) accounts for the most number of deaths among women with gynecological malignancies in the United States. Approximately 80% of EOC patients are diagnosed with disease that has disseminated beyond the confines of the ovaries. The five year survival rate for patients with advanced stage EOC is less than 30% and the recurrence of chemoresistant disease is high. Identifying the mechanisms that control peritoneal metastasis of EOC is therefore critical for improving treatment of advanced stage disease. The homeobox gene DLX4 encodes a transcription factor that is absent from most normal adult tissues. Previous studies from our …

Differential Pax5 Levels Promote Mcl Dispersal And Progression And Predict A Poor Prognosis In Advanced Mcl Patients, Albert Teo

Dissertations and Theses (Open Access)

Although PAX5 conditional silencing in mice models led to aggressive lymphoma formation, there has been a lack of understanding in the precise functions of PAX5 in human B cell cancers. PAX5 expression is used to diagnose different B cell lymphoma in the clinic including mantle cell lymphoma (MCL), which is one of the most aggressive B cell cancers. PAX5 levels in MCL patients were significantly repressed compared to normal B cells. Surprisingly, we found there were quantitative differences in PAX5 expression levels within MCL patient tissues, which prompted us to silence PAX5 in MCL cell lines to characterize PAX5 functions …

Nprl2/Tusc4 Functions As A Tumor Suppressor By Regulating Brca1’S Stability Via The E3 Ubiquitination Pathway, Yang Peng

Dissertations and Theses (Open Access)

Expression of the tumor suppressor protein BRCA1 is frequently lost in breast cancer patients, and the loss of its expression is associated with disruption of various critical functions in cells and cancer development. In the present study, we demonstrate through microarray analysis that cells with tumor suppressor candidate 4 (NPRL2/TUSC4) knockdown show critical changes to cell cycle, cell death pathways and a global impact on cancer development. More importantly, we observed a clear cluster pattern of NPRL2/TUSC4-knockdown gene profiles with established homologous recombination (HR) repair defect signature. Additionally, NPRL2/TUSC4 protein physically interacts with the E3 ligase HERC2 and prevents ubiquitin …

Jab1 Negatively Regulates Pten And Promotes Resistance To Trastuzumab In Her2-Positive Breast Cancer, Thuy T. Vu

Dissertations and Theses (Open Access)

HER2-positive breast cancer, which is characterized by the over-expression of the HER2 onco-protein, accounts for approximately 20% of all breast cancer cases. Trastuzumab (Herceptin), the first targeted therapy approved for HER2-positive disease, potently prevents the activation of signaling pathways downstream of HER2 and significantly improves patients’ outcomes. However, resistance to trastuzumab is inevitable; such resistance can occur through reduced expression of PTEN protein.

Jab1 is over-expressed in 50% of primary cancers and 90% of metastatic tumors. Our lab previously showed that depletion of Jab1 in combination with trastuzumab treatment up-regulated PTEN in mouse xenografts refractory to trastuzumab. PTEN was not …

Epidermal Growth Factor Receptor Induces Fyn Expression Via Up-Regulation Of P47phox In Glioblastoma Multiforme, Blake P. Johnson

Dissertations and Theses (Open Access)

Src family kinases (SFKs) are commonly over-expressed and/or activated in glioblastoma multiforme (GBM), where they serve as key mediators of GBM cell proliferation, survival, invasion and angiogenesis. Mechanisms of allosteric SFK activation are well described; however, the SFK Fyn is commonly up-regulated at the mRNA level in multiple human cancers, including GBM, where the mode of increased expression is poorly understood. Since activating mutations in the epidermal growth factor receptor (EGFR) are commonly occurring in GBM, we examined whether EGFR could induce Fyn expression. Here, we found that wild-type EGFR, and to a greater extent hyper-activating EGFR mutants, EGFRΔIII and …

Targeting Cox-2 And Rank In Aggressive Breast Cancers: Inflammatory Breast Cancer And Triple-Negative Breast Cancer, Monica Elizabeth Reyes

Dissertations and Theses (Open Access)

Inflammatory breast cancer (IBC) and triple-negative breast cancer (TNBC) are two highly aggressive breast cancer subtypes associated with a poor outcome. Despite sensitivity to current treatment, these breast cancers subtypes have a high recurrence rate and proclivity to metastasize early. The aggressiveness of IBC and TNBC have been linked to CSCs and epithelial to mesenchymal transition (EMT), which are critical features of breast cancer progression and metastasis. The clinical challenge faced in the treatment of IBC and TNBC is finding a treatment strategy to target the cancer stem-like (CSC) population to block metastasis. Cyclooxygenase-2 (COX-2) and receptor activator of nuclear …

Dual Assembly Nanoparticles Achieve Sustained Silencing Of Znf304: A Novel Transcription Factor For Β1 Integrin, Burcu Aslan

Dissertations and Theses (Open Access)

Ovarian cancer (OC) is a highly metastatic disease, but no effective strategies to this process currently are known. Here, an integrated computational analysis of The Cancer Genome Atlas ovarian cancer dataset coupled with experimental validation identified a novel zinc finger transcriptional factor 304 (ZNF304) as one of the key factors for ovarian cancer metastasis. High tumoral ZNF304 expression was associated with poor overall survival in ovarian cancer patients. Through reverse phase protein array analysis, we demonstrated that ZNF304 promotes multiple proto-oncogenic pathways important for cell survival, migration, and invasion. ZNF304 transcriptionally regulates β1 integrin, which subsequently regulates Src/focal adhesion kinase …

Targeting Cox-2 And Rank In Aggressive Breast Cancers: Inflammatory Breast Cancer And Triple-Negative Breast Cancer, Monica E. Reyes

Dissertations and Theses (Open Access)

Inflammatory breast cancer (IBC) and triple-negative breast cancer (TNBC) are two highly aggressive breast cancer subtypes associated with a poor outcome. Despite sensitivity to current treatment, these breast cancers subtypes have a high recurrence rate and proclivity to metastasize early. The aggressiveness of IBC and TNBC have been linked to CSCs and epithelial to mesenchymal transition (EMT), which are critical features of breast cancer progression and metastasis. The clinical challenge faced in the treatment of IBC and TNBC is finding a treatment strategy to target the cancer stem-like (CSC) population to block metastasis. Cyclooxygenase-2 (COX-2) and receptor activator of nuclear …

Attachment, Vagal Tone, And Co-Regulation During Infancy, Jessica Chloe Hansen

Theses and Dissertations

This study examined the development of attachment as it relates to co-regulation and vagal tone over the second half of the first year of life. Links to infants' attachment and developmental status were also examined. Symmetrical and unilateral co-regulated patterns of interactions at 6 months demonstrated significant linkages with attachment. Developmental status did not show direct linkages with attachment. Direct links between vagal tone and attachment were also not identified. Correlations between co-regulation and vagal tone at the 6 month time point were identified. Findings suggest an important role of co-regulation as it relates to attachment development. Future studies may …

Optimized Photogrammetric Network Design With Flight Path Planner For Uav-Based Terrain Surveillance, Ivan Yair Rojas

Theses and Dissertations

This work demonstrates the use of genetic algorithms as a stochastic optimization technique for developing a camera network design and the flight path for photogrammetricapplications using Small Unmanned Aerial Vehicles. This study develops a Virtual Optimizer for Aerial Routes (VOAR) as a new photogrammetric mapping tool for acquisition of images to be used in 3D reconstruction. 3D point cloud models provide detailed information on infrastructure from places where human access may be difficult. This algorithm allows optimized flight paths to monitor infrastructure using GPS coordinates and optimized camera poses ensuring that the set of images captured is improved for 3D …

Small Mammals Matter? Linking Plant Invasion, Biotic Resistance, And Climate Change In Post-Fire Plant Communities, Rory Charles O'Connor

Theses and Dissertations

The introduction and establishment of exotic species can profoundly alter ecosystems. Two exotic species drastically changing the landscape of deserts in western North America are Bromus tectorum L. and Bromus rubens L. Through the buildup of biomass and slow decomposition rates in deserts these two exotic annual grasses can alter fire regimes that change the plant and animal community dynamics in the ecosystems. To better understand the ecological mechanisms that could restrict or alter the patterns of invasive plant establishment we established a replicated full factorial experiment in the Great Basin and Mojave Desert. The combinations of factors being manipulated …

Targeted Drug Delivery System For Kidney And/Or Liver Failure Patients Using Human Serum Albumin, Sean Bedingfield

Undergraduate Honors Capstone Projects

Compromised liver and/or kidney function reduces the acceptable dosage of a variety of medications that can be administered to patients. These patients still have a need for drugs such as nonsteroidal anti-inflammatory drugs (NSAIDs), antivirals, and antibiotics. The project goal is to provide a drug delivery system to accommodate these reduced dosage limits with added therapeutic benefits to address symptoms of liver or kidney failure. Localized drug delivery allows for a smaller, concentrated dose rather than inundating the patient's system with the drug of interest. Human serum albumin (HSA) is a researched candidate for drug delivery with therapeutic properties. HSA …

Computational Exploration Of Chaotic Dynamics With An Associated Biological System, Akshay Galande

All Theses

Study of microbial populations has always been topic of interest for researchers. This is because microorganisms have been of instrumental use in the various studies related to population dynamics, artificial bio-fuels etc. Comparatively short lifespan and availability are two big advantages they have which make them suitable for aforementioned studies. Their population dynamic helps us understand evolution. A lot can be revealed about resource consumption of a system by comparing it to the similar system where bacteria play the role of different factors in the system. Also, study of population dynamics of bacteria can reveal necessary initial conditions for the …

Deveopment Of Explant Registry And Mechanical Testing Of Pristine And Explained Surgical Mesh, Colin Burns-Heffner

All Theses

Abdominal hernia repair is the most commonly performed general surgical procedure, with synthetic surgical mesh commonly used to buttress the defect in the abdominal wall. A majority of surgical mesh is made from Polypropylene (PP), which has been shown to invoke a foreign body response as long as the material remains in the body. Complications such as chronic pain require further investigation of mesh performance in hernia repair to better understand how performance differs for various surgical mesh materials. The broad objective of this thesis is to quantitatively characterize surgical mesh after exposure to human physiology in an in-vivo environment. …

Determining The Fate Of Non-O157 Shiga Toxin-Producing Escherichia Coli In Dairy Compost During Storage Using The Optimized Detection Method, Hongye Wang

All Theses

Shiga toxin-producing Escherichia coli (STEC), a member of Enterobacteriaceae family, has been recognized as emerging pathogens. Dairy compost is commonly applied to farmland as a soil amendment. Despite the agricultural benefit of manure-based soil amendment, the inadequately treated compost can contribute to fresh produce contamination on the farm. Moreover, the epidemiological results showed that the non-O157 STEC cases have surpassed those of E. coli O157. Therefore, it is critical to evaluate the behavior of non-O157 STEC strains in the dairy manure-based compost. The objectives of this study were to: 1) optimize a culturing method for detecting non-O157 STEC from dairy …

Combining Modified Atmosphere Packaging And Nisin To Extend The Shelf Life Of Atlantic Salmon (Salmo Salar), Dong Han

All Theses

Atlantic salmon is often used in laboratory experiments to represent marine fishes. Many researchers try to optimize the levels and dosage of preservatives to maintain the freshness and extend the shelf-life of Atlantic salmon. Little information has been provided about the effectiveness of combined method between MAP and nisin, especially on the preservation of Atlantic salmon. Strong evidences suggest that MAP associated with nisin may have a potential to improve Atlantic salmon storage quality. Preservation effectiveness of combining modified atmosphere package (MAP) and nisin on fresh Atlantic salmon was determined using various methods. Six groups of farmed Atlantic salmon were …

Do I Have Enough Money? An Examination Of The Roles Of Income And Income Perceptions On Nursing Turnover Intentions, Janelle Cheung

All Theses

Economic stress is an understudied, but potentially critical, concern that deserves more attention in the literature because it has important implications for employees and organizations. The present study sought to bring researchers and practitioners' attention to this area of research by examining the impact of income and income perceptions on turnover intentions. Very few published studies have investigated the mechanisms underlying the relationship between income and turnover intentions. As a novel contribution, the present study examined how perceived adequacy of current and future income each and simultaneously mediated the relationship between income and turnover intentions. Further, the study tested whether …

Fast Fission Neutron Detection Using The Cherenkov Effect, Matthew Millard

All Theses

The Cherenkov effect in optically clear media of varying indices of refraction and composition was investigated for quantification of fast neutrons. The ultimate application of the proposed detection system is criticality monitoring. The optically clear medium, composed of select target nuclei, was coupled to a photomultiplier tube. Neutron reaction products of the target nuclei contained within the optical medium emit beta particles and gamma rays that produce Cherenkov photons within the medium which can be detected. Assessed media include quartz (SiO2), sapphire (Al2O3), spinel (MgAl2O4), and zinc sulfide (ZnS), which were irradiated with un-moderated 252Cf. Monte Carlo N-Particle (MCNP) code …

Transformation Of Uranium In A Geological Environment, Derrell Hood

All Theses

Incorporation of uranium into iron oxide minerals is a promising mechanism for the environmental immobilization of U(VI). In this study, synthesized hematite was doped with uranium and analyzed with SEM-EDS, TEM, XRD, and ICP-MS. The results of this analysis strongly indicate uranium incorporation into the mineral, as well as the possible presence of a co-precipitated uranium mineral clarkeite. Preliminary results also shows an increase in the amount of uranium associated with the hematite particles as a function of mineral aging. Cyclic Voltammetry (CV) was used to induce and characterize electrochemical changes of uranium in the doped hematite system; these changes …

The Effects Of Conjugated Linoleic Acid Supplementation On Lipopolysaccharide-Challenged Synoviocytes, Allison Millican

All Theses

Osteoarthritis is one of the leading causes of lameness in the athletic horse. Cases of equine osteoarthritis typically present with synovitis, or inflammation of the synovium. This inflammation in the synovium leads to the production of inflammatory cytokines and eicosanoids. Although these downstream products can be beneficial, overproduction can lead to degradation of cartilage and joint disease. Opportunities to help mitigate or decrease inflammation within the joint are of current interest to the equine industry. One method being investigated is nutritional supplementation. The anti-inflammatory effects demonstrated by CLA supplementation make it a potential prospect for utilization in mitigating joint inflammation. …

The Effects Of Probiotics Supplementation On Health Using Caenorhabditis Elegans As A Model System, Miranda Klees

All Theses

The 'Western Diet,' prominent among developed nations, often refers to a diet rich in meat proteins and refined sugars. Western society may in part be plagued with obesity and obesity related diseases due to a diet enriched with glucose. With an increasing glycemic index observed in Western society, it comes to no surprise that obesity, diabetes, heart disease, and other obesity related diseases are on the rise. The Centers for Disease Control and Prevention describes obesity as an epidemic, affecting more than 35% of U.S. citizens. Shortened lifespan and increased susceptibility to pathogens are associated with these diseases and linked …

Using Gis To Prioritize Green Infrastructure Installation Strategies In An Urban Watershed, Lauren Owen

All Theses

This study seeks to quantify runoff volume generation and peak flow rates from the urban Sand River Headwaters to determine the most effective placement of additional green infrastructure in Aiken, SC. ArcMap 10.1, HEC-GeoHMS, and HEC-HMS were used to delineate a total outlet watershed along with subwatershed(s) for urban stormwater infrastructure system by 'burning' the stormwater system at an artificial elevation below the existing topologically-based Digital Elevation Model (DEM). The result was a higher resolution DEM that allowed for storm routing and subsequent volume and flow predictions compared to that based on the original DEM created by using Light Detecting …

Fabrication And Characterization Of Magnetic Nanoparticle Composite Membranes, Akeem Cruickshank

All Theses

To effectively and accurately deliver drugs within the human body, both new designs and components for implantable micropumps are being studied. Designs must ensure high biocompatibility, drug compatibility, accuracy and small power consumption. The focus of this thesis was to fabricate a prototype magnetic nanoparticle membrane for eventual incorporation into a biomedical pump and then determine the relationship between this membrane deflection and applied pneumatic or magnetic force. The magnetic nanoparticle polymer composite (MNPC) membranes in this study were composed of crosslinked polydimethylsiloxane (PDMS) and iron oxide nanoparticles (IONPs). An optimal iron oxide fabrication route was identified and particle size …

Associations Between Travel Behavior And The Academic Performance Of University Students, Qianying Wu

All Theses

Purpose: Different travel behavior, particularly the choice of commuting modes, will have different impacts on students. On one hand, it has been suggested that active commuting (walking, cycling, and taking transit) will add routine daily exercise. Moreover, health benefits (improved cognitive function and reduced anxiety) from physical activity might increase students' academic performance. Nevertheless, too much physical activity may reduce the time for students to study. Travel time may shorten study time, and study time has been identified as positively contributing to academic performance. Considering that there is limited research examining travel behavior and academic achievement of university students, this …

Inhibition Of Vibrio Cholerae Biofilm Formation By Water-Soluble Cranberry Extracts, Daniel Pederson

All Theses

Vibrio cholerae, a Gram-negative bacterium found in natural aquatic environments, is the causative agent of cholera, a severe diarrheal disease most commonly spread through drinking water. An essential component to this pathogen's success and persistence in the environment is its ability to attach to both biotic and abiotic surfaces via biofilm formation. Biofilms not only aid in surface attachment, but also provide a barrier that protects and enhances survival. Water-soluble extracts from the North American cranberry (Vaccinium macrocarpon) were found to dramatically inhibit V. cholerae biofilm formation at a low concentration of 2mg/ml. This inhibition was not due to acidification …

A Model Of The Diurnal Variation In Lake Surface Temperature, Jonathan L. Hodges

All Theses

Satellite measurements of water surface temperature can benefit several environmental ap-plications such as predictions of lake evaporation, meteorological forecasts, and predictions of lake overturning events, among others. However, limitations on the temporal resolution of satellite mea-surements restrict these improvements. A model of the diurnal variation in lake surface temperature could potentially increase the effective temporal resolution of satellite measurements of surface tem-perature, thereby enhancing the utility of these measurements in the above applications. Herein, a one-dimensional transient thermal model of a lake is used in combination with surface tempera-ture measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard the …

Human Whole-Blood (1)H2o Longitudinal Relaxation With Normal And High-Relaxivity Contrast Reagents: Influence Of Trans-Cell-Membrane Water Exchange, Gregory J. Wilson, Mark Woods, Charles S. Springer Jr., Sarah Bastawrous, Puneet Bhargava, Jeffrey H. Maki

Chemistry Faculty Publications and Presentations

PURPOSE: Accurate characterization of contrast reagent (CR) longitudinal relaxivity in whole blood is required to predict arterial signal intensity in contrast-enhanced MR angiography (CE-MRA). This study measured the longitudinal relaxation rate constants (R₁ ) over a concentration range for non-protein-binding and protein-binding CRs in ex vivo whole blood and plasma at 1.5 and 3.0 Tesla (T) under physiologic arterial conditions.

METHODS: Relaxivities of gadoteridol, gadobutrol, gadobenate, and gadofosveset were measured for [CR] from 0 to 18 mM [mmol(CR)/L(blood)]: the latter being the upper limit of what may be expected in CE-MRA.

RESULTS: In plasma, the ¹H2 O R …

Spatial Distribution And Genetic Variability Of Reniform And Lance Nematodes In Cotton Agroecosystems, Claudia Holguin

All Dissertations

Rotylenchulus reniformis (reniform nematode) and Hoplolaimus columbus (Columbia lance nematode) are two of the main plant-pathogenic nematode species affecting cotton production in the United States. For the selection and implementation of effective management practices it is important to understand distribution patterns and population genetic structure of these two nematodes in cotton agroecosystems. In a three-year field study, the spatial distribution of reniform nematode was characterized in two commercial fields in South Carolina to determine the effects of relations with soil texture and crop rotation on reniform nematode distribution (Chapter 1). Results of this project suggest that population densities of reniform …

Development Of A Translational, Tissue-Engineered Approach To Replacement Of Myocardial Infarct Scar Tissue, Jason Schulte

All Dissertations

Myocardial infarction (MI) affects nearly 600,000 individuals each year, and the resulting damage initiates a pathophysiological progression towards congestive heart failure (CHF). A shortage of donor organs precludes heart transplantation as a practical solution, and neither surgical intervention nor stem cell therapy have yielded consistent and sufficiently positive results in clinical investigation. To prevent CHF, prospective therapies must target the cause of the maladaptive cardiac remodeling which precedes it--the nonfunctional, dyskinetic infarct scar--and aim to replace it with functional cardiac muscle. Tissue engineering holds promise for the development of novel therapies to either halt or reverse post-MI cardiac remodeling. However, …