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The Role Of Post-Translation Regulation Of Twist Expression In The Tumor Progression Of Squamous Cell Carcinoma Of Head And Neck, Ying-Wen Su

Dissertations and Theses (Open Access)

Squamous cell carcinoma of head and neck (SCCHN) is the tenth most common cancer in the world. Unfortunately, the survival of patients with SCCHN has not improved in the last 40 years. Therefore new targets for therapy are needed, and to this end we are studying signaling pathways activated by IL-6 which we have found stimulates cell migration and soft agar growth in SCCHN. Our data show that IL-6 increases TWIST expression in a transcription-independent mechanism in many SCCHN cell lines. Further investigation reveals TWIST can be phosphorylated upon IL-6 treatment. By computation prediction (http://scansite.mit.edu/motifscan_seq.phtml ), we found that TWIST …

Characterization Of The Agrobacterium Tumefaciens Virb2 Pilin Of The Virb/D4 Type Iv Secretion System, Jennifer Kerr

Dissertations and Theses (Open Access)

The Agrobacterium tumefaciens VirB/D4 type IV secretion system (T4SS) delivers oncogenic T-DNA and effector proteins to susceptible plant cells. This leads to the formation of tumors termed Crown Galls. The VirB/D4 T4SS is comprised of 12 subunits (VirB1 to VirB11 and VirD4), which assemble to form two structures, a secretion channel spanning the cell envelope and a T-pilus extending from the cell surface. In A. tumefaciens, the VirB2 pilin subunit is required for assembly of the secretion channel and is the main subunit of the T-pilus. The focus of this thesis is to define key reactions associated with the T4SS …

Agrobacterium Virb10 Contributions To Type Iv Substrate Secretion, T-Pilus Biogenesis, And Outer Membrane Pore Formation, Isaac Garza

Dissertations and Theses (Open Access)

The VirB/D4 type IV secretion system (T4SS) of Agrobacterium tumefaciens functions to transfer substrates to infected plant cells through assembly of a translocation channel and a surface structure termed a T-pilus. This thesis is focused on identifying contributions of VirB10 to substrate transfer and T-pilus formation through a mutational analysis. VirB10 is a bitopic protein with several domains, including a: (i) cytoplasmic N-terminus, (ii) single transmembrane (TM) α-helix, (iii) proline-rich region (PRR), and (iv) large C-terminal modified β-barrel. I introduced cysteine insertion and substitution mutations throughout the length of VirB10 in order to: (i) test a predicted transmembrane topology, (ii) …

Analyzing The Role Of Αvβ8 Integrin In Glioma-Induced Angiogenesis, Jeremy H. Tchaicha

Dissertations and Theses (Open Access)

In this study we aimed to determine the functional roles for αvβ8 integrin in astrocytoma-induced angiogenesis. These studies originate from our analyses of αvβ8 integrin in developmental brain angiogenesis. αv and β8 knockout (KO) mice develop brain-specific vascular phenotypes that resemble vascular pathologies observed in the malignant astrocytoma, glioblastoma multiforme (GBM). Indeed, a murine xenograft model of astrocytoma suggested a role for the integrin in glioma-induced angiogenesis. Primary mouse astroglia were cultured from wild type (WT) and β8 KO neonates and were immortalized (HPV:E6/E7) and transformed (HRas:G12V). WT and β8 KO transformed astroglia were intracranially injected into athymic mice. WT …

Elucidating The Role Of Cd44 Expression On Mesenchymal Stem Cells Within The Tumor Microenvironment, Erika L. Spaeth

Dissertations and Theses (Open Access)

The tumor microenvironment is comprised of a vast array of heterogeneous cells including both normal and neoplastic cells. The tumor stroma recruitment process has been exploited for an effective gene delivery technique using bone marrow derived MSC. Targeted migration of the MSC toward the tumor microenvironment, while successful, is not yet fully understood. This study was designed to assess the role of CD44 in the migration of MSC toward the tumor microenvironment and to determine the implications of CD44-deficient MSC within the tumor stroma. Inhibition of MSC migration was evaluated through a variety of methods in vitro and in vivo …

14-3-3sigma Negatively Regulates The Stability And Subcellular Localization Of Cop1, Chun-Hui Su

Dissertations and Theses (Open Access)

Mammalian constitutive photomorphogenic 1 (COP1), a p53 E3 ubiquitin ligase, is a key negative regulator for p53. DNA damage leads to the translocation of COP1 to the cytoplasm, but the underlying mechanism remains unknown. We discovered that 14-3-3σ controlled COP1 subcellular localization and protein stability. Investigation of the underlying mechanism suggested that, upon DNA damage, 14-3-3σ bound to phosphorylated COP1 at S387, resulting in COP1 translocation to the cytoplasm and cytoplasmic COP1 ubiquitination and proteasomal degradation. 14-3-3σ targeted COP1 for degradation to prevent COP1-mediated p53 degradation, p53 ubiquitination, and p53 transcription repression. COP1 expression promoted cell proliferation, cell transformation, and …

Dynamic Remodeling Of The Stressed Heart: Role Of Protein Degradation Pathways, Deborah Vela

Dissertations and Theses (Open Access)

The heart is a remarkable organ. In order to maintain its function, it remodels in response to a variety of environmental stresses, including pressure overload, volume overload, mechanical or pharmacological unloading and hormonal or metabolic disturbances. All these responses are linked to the inherent capacity of the heart to rebuild itself. Particularly, cardiac pressure overload activates signaling pathways of both protein synthesis and degradation. While much is known about regulators of protein synthesis, little is known about regulators of protein degradation in hypertrophy. The ubiquitin-proteasome system (UPS) selectively degrades unused and abnormal intracellular proteins. I speculated that the UPS may …

Effects Of Combined Bevacizumab And Paclitaxel On Tumor Interstitial Fluid Pressure In A Preclinical Breast Cancer Model, Ricardo Hugo Alvarez

Dissertations and Theses (Open Access)

Effects of Combined Bevacizumab and Paclitaxel on Tumor Interstitial Fluid Pressure in a Preclinical Breast Cancer Model by Ricardo H. Alvarez Several mechanisms of cell resistance are often accountable for unsuccessful chemotherapy against cancer. Another reason, which has received increased attention, is the inefficient transport of anticancer drugs into tumor tissue. These impaired transports of chemotherapy into the tumor have been attributed to abnormal microvasculature and to pathologically increased tumor hypertension also called: interstitial fluid pressure (IFP). The pathophysiological processes leading to elevated tumor IFP are poorly understood. Here, in a preclinical breast cancer model, it is argued that a …

Temozolomide And Bevacizumab Therapy In Advanced Hemangiopericytoma/ Solitary Fibrous Tumor, Min S. Park

Dissertations and Theses (Open Access)

Tumors comprising the spectrum of hemangiopericytoma/ malignant solitary fibrous tumor (HPC/SFT) are thought to arise from fibroblasts and represent a small subset of soft tissue sarcomas. Surgery is typically the treatment of choice for localized disease, with reported 10-year overall survival rates of 54-89% after complete surgical resection. However, for the approximately 20% of HPC/SFT patients who eventually develop local recurrences and/or distant metastases, options for effective treatment are limited and are poorly defined. Alternative therapeutic options are therefore needed for improved palliation and disease control. We hypothesize that HPC/SFT are a spectrum of soft tissue tumors with unique clinical, …

Mcam/Muc18 Regulates Melanoma Progression By Modulating The Expression Of Id-1, Maya Zigler

Dissertations and Theses (Open Access)

The acquisition of the metastatic melanoma phenotype is associated with increased expression of the melanoma cell adhesion molecule MCAM/MUC18 (CD146). However, the mechanism by which MUC18 contributes to melanoma metastasis remains unclear. Herein, we stably silenced MUC18 expression utilizing lentivirus-incorporated small hairpin RNA, in two metastatic melanoma cell lines, A375SM and C8161, and conducted cDNA microarray analysis. We identified and validated that the transcriptional regulator, Inhibitor of DNA Binding-1 (Id-1), previously shown to function as an oncogene in several malignancies, was downregulated by 5.6-fold following MUC18 silencing. Additionally, we found that MUC18 regulated Id-1 expression at the transcriptional level via …

Policy Relevant Heterogeneity In The Value Of Statistical Life: New Evidence From Panel Data Quantile Regressions, W. Kip Viscusi, Thomas J. Kniesner, James P. Ziliak

Vanderbilt Law School Faculty Publications

We examine differences in the value of statistical life (VSL) across potential wage levels in panel data using quantile regressions with intercept heterogeneity. Latent heterogeneity is econometrically important and affects the estimated VSL. Our findings indicate that a reasonable average cost per expected life saved cut-off for health and safety regulations is $7 million to $8 million per life saved, but the VSL varies considerably across the labor force. Our results reconcile the previous discrepancies between hedonic VSL estimates and the values implied by theories linked to the coefficient of relative risk aversion. Because the VSL varies elastically with income, …

The Determinants Of Entrepreneurial Income In South Carolina, Devin Swindall

All Theses

Supporters claim that entrepreneurship is critical to building and sustaining the economy of urban and rural areas across the nation. Proponents argue that economic development practices that enhance and support entrepreneurship are essential because they cultivate innovation which, in turn, provides the area with new jobs, new wealth, and a better quality of life. However, self-employment income growth in South Carolina in particular and in the United States in general has lagged growth in income from other sources. This fact raises the need to study the determinants of self-employed income. Using the literature as a guide, a conceptual model was …

Buffering Effects Of Positive Mentoring On Mentor Burnout: Generative Concern And Perceived Organizational Support As Moderators, Meline Schaffer

All Theses

Burnout among employees has personal and organizational consequences. Negative effects of burnout include lowered individual adjustment as well as disengagement from the organization. Given this, both psychologists and practitioners may benefit from understanding ways to decrease this factor among employees.
One organizational experience that has the potential to decrease burnout is mentoring. While the advantages of mentoring relationships for protŽgŽs are well-documented, this study examines the potentially beneficial effects of positive mentoring relationships for the mentor, focusing on the reduction of burnout as a dependent variable. While benefits of mentoring may lead to reduced burnout, recent research suggests that negative …

Response Of Warm Season Turfgrasses To Reduced Light Environments, Jeffrey Atkinson

All Theses

Shade or low light tolerance is an increasingly important issue to turf managers as they are often expected to grow turf in less than ideal agronomic conditions. As permanent structures such as residential buildings add to already problematic shade caused by trees, and other barriers, new solutions are needed to help turf managers provide acceptable turf conditions. The plant growth regulator trinexapac-ethyl (TE) can lessen negative responses of turfgrass to shade.
Two experiments were conducted during the summers of 2008 and 2009 to evaluate various grasses under a reduced light environment (RLE). In the first study, performance of `Diamond' zoysiagrass …

Chemical Composition And Antioxidant Properties Of Maya Nut (Brosimum Alicastrum), Hatice Kubra Tokpunar

All Theses

ABSTRACT
Maya nut was investigated in term of its moisture, ash content, antioxidant activities, phenolic components by high pressure liquid chromatography-ultraviolet detector (HPLC-UV) and fatty acid composition by gas chromatography-flame ionization detector (GC-FID). The results showed that Maya nut was mainly composed of 55.06% linoleic acid (C18:2 n6), 27.2% palmitic acid (C16:0), 6.26% stearic acid (C18:0), 9.9% linolenic acid (C18:3 n3), and 3.36% Cis-11-Eicosenoic (C20:1). Maya nut possesses a higher content of polyunsaturated fatty acids (PUFAs) (linoleic and linolenic acid), but lower content of monounsaturated fatty acids (MUFAs) than canola oil and olive oil. The antioxidant capacities and total phenolic …

In Vitro Boosting And Expansion Of Tumor Infiltrating Killer T Cells, Chunlei Mei

All Theses

Immune cell tumor infiltration represents one of the mechanisms that the immune system responds to tumor cells. The tumor infiltrated immune cells include lymphocytes (TIL), dendritic cells (DCs), macrophages, and natural killer (NK) cells. Although TILs have been extensively studied in order to develop adoptive transfer based immunotherapies, how to effectively isolate, culture, and in vitro boosting the killer cells from TILs remains a challenge. Meanwhile, OK-432, a heat and penicillin-treated lyophilized preparation of the low-virulence strain of Streptococcus pyogenes, has been shown to exhibit immunomodulatory activities and potential antitumor therapeutic function, including the activation of DCs, neutrophils, macrophages, lymphocytes, …

The Synthesis, Characterization, And Electrochemical Study Of Tris(Pyrazolyl)-Type Iron(Ii) Complexes, Iron(Ii) Sulfur- And Selenium-Containing Complexes, And Tris(Pyrazolyl)-Type Ruthenium(Ii) Complexes, Christopher Underwood

All Theses

Highly reactive radical species such as hydroxyl radical cause oxidative stress, resulting in chronic or degenerative diseases. In the biological Fenton reaction, iron(II) generates hydroxyl radical, OH, but only within a specific electrochemical potential window (-324 mV to 640 mV). Selenium and sulfur compounds have been extensively studied for their antioxidant properties, and they may exert their effects by binding iron(II) and shifting its electrochemical potential out of this window. This work has investigated the synthesis and electrochemical characterization of iron(II) chalcogenate complexes and iron(II) chalcogenone complexes. Cyclic voltammetry (CV) of [Fe(EPh)4][(PPh4)2] (E = S, Se) complexes shows Fe2+/3+ redox …

Characterization Of Transgenic Plum Lines Expressing Gastrodia Antifungal Protein (Gafp)-1, Hetalben Kalariya

All Theses

The Gastrodia antifungal protein (GAFP-1) is a mannose-binding lectin originating from the Asiatic orchid Gastrodia elata. It has potential for conferring resistance to fungal and non-fungal pathogens in other plants which is currently being investigated. The goals of this research project were to determine (i) the potential movement of GAFP-1 protein from transgenic rootstocks into the non-transgenic scion of chimeric-grafted trees (ii) the levels of GAFP-1 protein in lines of the cultivar Bluebyrd expressing the gene gafp-1 under the control of the polyubiquitin promoter bul409, and (iii) the susceptibility of selected lines to the root pathogens Phytophthora cinnamomi Rands and …

Style And Electronic Communication: The Accommodation Of Scientific Risks In The Sierra Magazine, Erin Dalton

All Theses

This thesis focuses on how style accommodates scientific risks for public audiences in Magazine articles. Language has previously been unexplored in risk communication; in accommodation research, style has not been investigated. Responding to these gaps in research, this study combines two unexplored dimensions--risk communication and accommodation--to show how syntax, diction, and metaphor resituate technical language and ideas in scientific risk studies for readers. First, interviews with editors and writers will provide a rich understanding of how their editing and composition practices influence accommodation processes. From there, an electronic communication analysis will illustrate how this medium can accommodate beyond text to …

Isolation, Characterization And Application Of Bacteriophage To Treat Hydrogen Sulfide Producing Bacteria In Raw Animal Materials Destined For The Rendering Process, Chao Gong

All Theses

In the United States, billions of pounds of animal by-products are generated by the food processing industry every year. Hydrogen sulfide producing bacteria (SPB) can utilize the sulfur-containing proteins and amino acids in the raw animal materials destined for the rendering process to produce harmful hydrogen sulfide (H2S) gas rapidly under the ambient conditions, resulting in hazardous working environments and inferior quality of finished products. In this study, the application of bacteriophage was explored as an effective solution for the elimination of H2S production in the rendering industry. The objectives of this study were to: 1) isolate and characterize strains …

Crime And Punishment: Insitutional Sanctions And Other Characteristics That Effect Campus Crime, Aldon Givens

All Theses

Crime, has and continues to be, a major issue in the world of institutions of higher education. Colleges and universities are constantly working on ways to prevent and improve crime on their respective campuses, which in most occasions includes collecting and reporting crime data to law enforcement agencies and the general public. By setting up punishment schemes and sanctions to deter criminal activity at their institution, administrators and faculty are looking for better, more efficient ways to influence the behavior or their students and steer them away from a life of criminal activity.
By studying existing literature, crime definitions, and …

4-H Leaders: Factors That Affect Their Persistence In The 4-H Youth Development Program, Regina Schinker

Dissertations

For over one hundred years, the 4-H youth development program has educated millions of children across the country in a variety of programs; from livestock husbandry to leadership skills. Like all programs that have endured, 4-H has had to adjust its focus as society has changed. One area in the 4-H program that has not changed is the heavy reliance on adult volunteer leaders to deliver the educational programs to 4-H youth. Because of the reliance on volunteer 4-H leaders, 4-H professionals and extension office staff are concerned about issues of retention.

The case study examines two related issues: First, …

Madd Message Effects: A Twelve-Year Randomized Trial, Una E. Medina

Communication ETDs

One out of three Americans undergoes drunk-driving crashes; 23% result in death. To deter DWIs (Driving While under Influence), MADD (Mothers Against Drunk Drivers) created VIPs (Victim Impact Panels) where victims impact offenders with gory stories, photos, and threats of punishments and loss of freedom, hoping this message will deter DWIs. It is remarkable that although the VIP message is considered a primary DWI intervention, yet no studies have investigated VIP message effects. VIP message effects, their persistence and decay, are chronicled here over the course of 12 years. This study extends an empirical investigation of VIPs, conducted by Woodall, …

Multilevel Antecedents Of Economic Stress, Mark Zajack

All Dissertations

Much of the literature on economic stress focuses on outcomes. This study assessed the antecedents that precede employee perceptions of economic strain. A multilevel framework of economic antecedents was proposed. The framework included objective indicators of the macroeconomic context as well as individual-level objective and subjective economic antecedents. It was hypothesized that antecedents within each of these categories of economic stress can fall into one of two dimensions: employment- or finance-related. Indicators of the macroeconomic context were gathered from the American Community Survey (ACS). Over 2,000 union employees of a large U.S. Midwestern retail chain provided individual employee-level economic information …

Resistance And Dna Repair Mechanisms Under Nitrosative Stress In Mammalian And Microbial Systems, Hyun-Wook Lee

All Dissertations

Living organisms are exposed a nitrosative stress mediated by reactive nitrogen species (RNS) that can cause DNA damage and mutation. DNA base deamination is a typical damage occurred under nitrosative stress, which results in conversion of cytosine (C) to uracil (U), adenine (A) to hypoxanthine (I), and guanine (G) to xanthine (X) or oxanine (O). Base excision repair (BER) is an important pathway to remove deaminated DNA lesions in mammalian and microbial systems. My dissertation work concerns with genes and enzymes involved in resistance to nitrosative stress and DNA glycosylases in the BER pathway. In chapter one, I will briefly …

A Study Of African American Forest Landowners In South Carolina: Implications For Land Ethic And Forest Stewardship, Keenan Adams

All Dissertations

African Americans account for a significant proportion of South Carolina`s
population but reportedly own a disproportionally smaller amount of land. Research indicates that landowners who hold significant sources of sustainable wealth and power can dramatically increase their quality of life and ultimately that of their communities. Current land loss trends for African Americans are increasing at an alarming rate, which may have larger social implications for this traditionally underserved population. The remaining African American landowners are a rapidly declining group, due to an assortment of factors (e.g., age, heirs property). Understanding the experiences of the residual African American forest landowners …

Population Variability Of Rotylenchulus Reniformis In Cotton Agroecosystems, Megan Leach

All Dissertations

Rotylenchulus reniformis, reniform nematode, is a highly variable species and an economically important pest in many cotton fields across the southeast. Rotation to resistant or poor host crops is a prescribed method for management of reniform nematode. An increase in the incidence and prevalence of the nematode in the United States has been reported over the last two decades. However it is not clear whether the observed increase is related to the emergence of novel populations that are more aggressive or have a higher fitness or shifts in host availability or susceptibility. The objectives of this research were to determine …

Novel Vascular Grafts Based On Polyphenol-Stabilized Acellular Tissue Scaffolds, Ting-Hsien Chuang

All Dissertations

The Cardiovascular diseases (CVDs) continue to be the leading cause of morbidity and mortality worldwide. The most common form of CVDs is occlusion of blood flow thus limiting blood supply to specific tissues or organs. Atherosclerosis is a leading cause of coronary heart disease and stroke, which were responsible for more than 25% of deaths in 2004.
The demand for vascular graft is huge. In United States alone, approximately 500,000 coronary artery bypass graft surgeries are performed annually. Synthetic polymers such as Dacron and ePTFE have been successfully applied in large diameter blood vessel prosthesis; however, for small diameter (inner …

Evaluation Of Factors That Modulate Cellular Adipogenesis For Breast Tissue Engineering Strategies, Cheryl Gomillion

All Dissertations

It is estimated that this year more than 200,000 women in the United States will be diagnosed with breast cancer. Treatment for most occurrences of breast cancer will often include surgical removal of the tumorigenic tissue, resulting in a soft tissue defect within the subcutaneous tissue of the skin. Post-surgical reconstruction methods are often sought by patients to restore the aesthetic function of the breast via cellular or non-cellular methods; however, because of complications associated with currently used methods for breast reconstruction, researchers are investigating tissue engineering methods to produce viable autologous adipose tissue for breast reconstruction.
Previous research in …

Development And Characterization Of Novel Sub-Coatings With Polymorphic Brookite Titania Nanoparticles: Enhanced Uv/Vis Photocatalytic Antibacterial And Anticancer Properties, Donna Weinbrenner

All Dissertations

ABSTRACT
Nosocomial and community infections and biofilm formation from bacteria has increased significantly through adaptation combined with overuse of broad spectrum antibiotics. Because the world population continues to escalate, hospitals and long-term managed care will also escalate, thereby increasing transmission of infections, lowering patients' quality of health. Another disease on the rise throughout the world is skin cancer. A treatment modality that would cause less deleterious effects on the patient would be ideal. These two seemingly different issues could be solved with one product. First an inexpensive, safe, and non-selective antimicrobial surface coating would enhance the hospital arena and a …