Digital Commons Network^™

The Discovery Of A Novel, Ras-Mediated Nore1a/Pmliv Tumor Suppressor Complex., Jessica Mezzanotte Sharpe

Electronic Theses and Dissertations

Ras is the most commonly activated oncogene in human cancer. Activated Ras drives cell growth and proliferation by activating multiple mitogenic signaling pathways. However, Ras also has the paradoxical ability to promote anti-growth, pro-apoptotic, and pro-senescent signaling. The signaling pathways of many of these biological effectors remain poorly defined. One group of proteins capable of promoting Ras-induced apoptosis and cell cycle arrest is the RASSF family of tumor suppressors. Novel Ras Effector 1A, or NORE1A, was the first member of this family discovered and is a bona fide tumor suppressor that is lost or inactivated in a number of different …

Characterization Of Pg1604 (Porz) As An Essential Component Of Type 9 Secretion System In Porphyromonas Gingivalis., Apurva Tadimari Prabhakar

Electronic Theses and Dissertations

Background: The numerous virulence factors of Porphyromonas gingivalis are essential for the organism to invade host tissues while escaping immune responses [1, 2]. Some of these factors, like major proteases referred to as gingipains, are secreted by a unique secretion system called PerioGate or Type IX Secretion System (T9SS). T9SS consists of a number of membrane and periplasmic proteins, which provide transportation only for proteins that possess a conserved C-terminal domain (CTD). The CTD functions as a specific recognition signal for the T9SS. PG1604 of P. gingivalis W83 is a CTD-containing protein, which has been shown in our initial studies …

Microfluidic Platform For Impedance Characterization Of Endothelial Cells Under Fluid Shear Stress., Vanessa Velasco

Electronic Theses and Dissertations

Endothelium dysfunction has been associated with many pathophysiological processes leading to cardiovascular diseases. Studying endothelium behavior is vital to understand the onset, prevention, and treatment of such diseases. Electrical impedance spectroscopy has been shown to provide a real-time in vitro evaluation of cell behavior including cell monolayer permeability. However, the majority of published work has been primarily with static cell culture models or macro-scale models that do not properly represent the physiological sizes, structures, and environmental conditions of human blood vessels. Within this dissertation, the design, fabrication, characterization, and application of a microfluidic impedance platform is presented for the in …

A Systems Biology Approach Identifies A Gene Regulatory Network In Parotid Acinar Cell Differentiation., Melissa Ann Metzler

Electronic Theses and Dissertations

Objective: This project sought to understand the gene regulatory networks that drive parotid salivary gland acinar cells to terminally differentiate, and drive expression of terminal differentiation genes in dedifferentiated ParC5 cells. Methodology: Laser capture microdissection was used to isolate acinar cells at multiple time points during differentiation. This important step allowed us to measure gene expression in a single and important cell type. A systems biology approach was taken to measure global mRNA and microRNA expression across acinar cell terminal differentiation in the rat parotid salivary gland. In ParC5 cells, the ER stress activator tunicamycin was used to stimulate Xbp1 …

Effects Of Acute Exercise On Postprandial Lipemia And Postprandial Glycemia, Stephen Decker

Electronic Theses and Dissertations

Introduction: Moderate-intensity aerobic exercise has been shown to attenuate the rise in triglycerides in during the postprandial period, however the effects of acute bouts of high-intensity exercise on postprandial lipemia and glycemia have not been explored. The purpose of this study was to examine the effects of acute high-intensity interval training on postprandial lipemia and postprandial glycemia.

Methods: Ten healthy males participated in a randomized crossover design consisting of one high-intensity exercise session and one sedentary control session, followed by consumption of a mixed meal. Blood triglyceride and glucose concentrations were monitored following the consumption of the meal.

Results: High-intensity …

Long-Term Overstory Vegetation Responses To Prescribed Fire Management For Longleaf Pine At Big Thicket National Preserve, Deanna M. Boensch

Electronic Theses and Dissertations

At the western edge of the longleaf pine (Pinus palustris) range, federal land managers have burned the forests of Big Thicket National Preserve to bring back the structure and diversity of the longleaf pine forest. In the early 1990’s, a four year study was conducted by Rice University, and the National Park Service continued monitoring the study’s fire ecology research plots. After two decades of data collection, ordination was applied to species abundance data to examine changes in vegetation communities from a variety of prescribed fire treatments and controls. The vegetation data was separated by size class to include overstory, …

Putting Christians On The Map : Topographic Mosaics From Late Antique Jordan As Representations Of Authority And Status., Tracey Elizabeth Eckersley

Electronic Theses and Dissertations

In this dissertation, I examine nine ecclesiastic floor mosaics from Late Antique Palaestina and Arabia that contain topographic motifs ­­˗ images of cities set in realistic or stylized landscapes. Previous interpretations of the pavements have been limited by two assumptions: that artists or bishops were solely responsible for determining the compositions, and that only religious interpretations were intended for church pavements. Inscriptions indicating that patrons were generally lay people and iconography that encourages secular interpretations complicates both assumptions. This study investigates the mosaics in light of Late Antique euergetism in order to determine why donors included architectonic elements in the …

Murakami-Ego : Collective Culpability And Selective Retention., Yun Kweon Jeong

Electronic Theses and Dissertations

The purpose of this thesis is to argue that Murakami’s art expresses the Japanese’s psychological suffering by showing their struggle between remembering themselves as victims but forgetting themselves as aggressors. I apply the Mitscherlichs’ psychoanalisys of the Germans’s psyche to the Japanese because their people have had similar experiences. The first section examines the history of Japan surrounding WWII in order to demonstrate its effects on the Japanese people’s psyche. The second section introduces Otaku to better understand Murakami’s art. The third section examines how selective retention works on the Japanese’s psyche. The fourth section analyzes how Murakami’s art represents …

When The Silver Screen Fades To Black : An Analysis Of Black Faces In Film., Travesheia Rashel Bass

Electronic Theses and Dissertations

The Black Film Industry emerged with the goal of challenging the misrepresented images of African Americans that were promoted in early American Films. The Black Film making process promoted a centrality of stories told from an Afrocentric point of view. This thesis analyzes how Black Film has been defined over the last sixteen years and how it has impacted American society. Films that were made by or in collaboration with African American writers, directors, and producers with a focus on the African American community (its values, cultural aesthetics, and practices) and featuring an all or primarily Black cast were found …

Effects Of Glyceollin On Mrna Expression In The Female Mouse Brain., Sanaya Firdaus Bamji

Electronic Theses and Dissertations

Glyceollins (Glys), produced by soy plants in response to stress, have anti-estrogenic activity in breast and ovarian cancer cell lines in vitro and in vivo. In addition to known anti-estrogenic effects, Glys exhibit mechanisms of action not involving estrogen receptor (ER) signaling. To date, effects of Glys on brain physiology and function are unknown. The purpose of the experiments summarized in this dissertation was to gain an understanding of the effects of Gly on brain-related functions in the female mouse brain through the observation of changes in gene expression. For our initial studies, we treated ovariectomized Swiss Webster (CFW) …

Effect Of Migration, Carrying Capacity, And Fecundity On The Formation Of Clinal Patterns During Range Expansions., Neha J. Angal

Electronic Theses and Dissertations

Range expansions, empirically and in simulations, lead to clinal patterns of genetic diversity. Clines are often used as spatial markers of past migrations. This study investigated the effects of migration, growth, and carrying capacities on clinal patterns during range expansions, using forward-time simulations in Nemo. Initial results show, in the absence of prior population structure, range expansions result in a loss of diversity strongly affected by migration, growth, and carrying capacity. This loss of diversity did not persist to the final generation, corresponding to 10,000 years, indicating clinal patterns are less durable than previously assumed—challenging the utility of clinal patterns …

Students’ Phonological Awareness Literacy Screening And School Readiness, Jeannette D. Triplett Mrs.

Electronic Theses and Dissertations

Public school kindergarten programs have become increasingly more academic and have educators debating about what skills best serve children in kindergarten that will prepare them for later academic achievement. The Phonological Awareness Literacy Screening (PALS) is a screening instrument used in Virginia to assess kindergarten students and students in grades 1 through 3. Kindergarten teachers want to make sure that with the more demanding curriculum, and increase in rigorous standards, that students enter kindergarten ready to learn.

The purpose of this study was to examine the relationship between students’ kindergarten PALS scores and first grade PALS scores in a southwestern …

Gamma-Radiation Exposure Alters The Cardiovascular Extracellular Matrix., Nicholas Allen

Electronic Theses and Dissertations

Ionizing radiation has been associated with various cardiovascular complications; however, the associated molecular changes from radiation exposure still remain largely uncharacterized. Alterations to the cardiovascular tissue microenvironment, i.e. the extracellular matrix (ECM), directly affect the function of integrated vascular cells, including cell adhesion, potential to form vessels, and endothelial permeability, which can promote cardiovascular pathologies. The ECM is constantly remodeled in response to stimuli, such as TGF-β1, which leads to excessive ECM accumulation. We hypothesize that radiation exposure will alter the cardiovascular ECM. Human Cardiac Fibroblasts (HCFs) were utilized to produce ECM as an in vitro model to study changes …

Learning Styles Of Physical Therapy And Physical Therapist Assistant Students In Accredited Physical Therapy Programs, Margaret A. Lowdermilk

Electronic Theses and Dissertations

The purpose of this study was to determine the learning styles of Doctor of Physical Therapy (DPT) students and associate degree Physical Therapist Assistant (PTA) students and identify any association between their learning styles and examine the association between gender and age by learning style.

Participants included 337 DPT and PTA students attending CAPTE accredited institutions with doctoral DPT or associate PTA programs in Tennessee and southwest Virginia. The Felder (1996) and Soloman Index of Learning Styles (ILS) was used to determine learning style preferences within 4 learning style dimensions (active-reflective, sensing-intuitive, visual-verbal, and sequential-global).

Demographics included program of study, …

Radiography Students: Factors Contributing To Their Stress And Methods Of Coping, Kayla A. Rosenbaum

Electronic Theses and Dissertations

College students experience high levels of stress, especially those in health care programs. The purpose of this study was to determine what factors contribute to Tennessee radiography student stress levels and the methods by which they cope with stress. Additionally, do demographic factors affect radiography student stress levels? The research was conducted February 4 to March 30, 2016. A survey was distributed to students in a radiography program at two and four year colleges in Tennessee. Participants were asked questions on factors that influence their stress levels, coping strategies, and health issues experienced in the past year. Descriptive statistics, independent …

Social Comparison Processes As Contributors To Consistent Physical Activity., Holly M. Knight

Electronic Theses and Dissertations

The present study examined the impact that attention to social comparison (SC) information may have on consistency in physical activity (PA) behaviors across genders. SC factors, including SC frequency, SC direction and trait tendency to compare (SCO) were assessed within the Dynamic Relapse Model (DRM) as markers of PA consistency within men and women. Participants were N=200 individuals engaging in physical activity at YMCA gym facilities. Data collection utilized cross-sectional methods including anthropomorphic data collection at the point of recruitment and online selfreport measures post-recruitment. High adherence to regular physical activity was observed, with participants reporting infrequent slips in PA …

Molecular Characterization Of Human Papillomavirus In Head And Neck Tumors., Sujita Khanal

Electronic Theses and Dissertations

Head and neck cancers (HNCs) are common causes of cancer-related deaths worldwide. An increasing incidence of subsets of HNCs is due to human papillomavirus (HPV). Other subsets are associated with tobacco and alcohol use. Determination of differential biomarkers and molecular mechanisms distinguishing HPV-associated and unassociated HNCs should improve diagnostic and therapeutic strategies. This study was designed to identify potential biomarkers for HPV detection, and to evaluate viral and host genetic and epigenetic mechanisms involved in HPV-associated HNCs. Overexpression of a cellular protein, p16INK4a, which is widely used as a surrogate marker for HPV-positive HNC, is non-specific because some HPV-negative cancers …

Molecular Docking, Synthesis And Evaluation Of Pyrrolo[2,1-C][1,4]Benzodiazepines Derivatives As Non-Β-Lactam Β-Lactamases Inhibitors, Joseph Osamudiamen Osazee

Electronic Theses and Dissertations

Our research aim was to design, synthesize, and study the competitive enzyme inhibition kinetics of pyrrolo[2,1-c][1,4]benzodiazepine (PBD) derivatives as potential non-²-lactam ²-lactamase inhibitors. All compounds (1-13) passed the Lipinski’s rule of 5 test and were docked into the active site of TEM-1 ²-lactamase. PBD derivatives 1-7 were synthesized in high yields and tested for their potency against TEM-1 and P99 ²-lactamases. Kinetic data showed that compounds 1, 4, 5, and 7 possessed inhibitory activity against TEM-1 ranging from 4-34 %. Docking results revealed significant interactive spanning of the active site of TEM-1 by PBDs. …

Synthesis, Characterization And Biological Evaluation Of Pyrrolo[2,1-C][1,4]Benzodiazepines For Cytotoxicity And Serine Β-Lactamases Inhibition, Joel K. Annor-Gyamfi

Electronic Theses and Dissertations

Pyrrolo[2,1-c][1,4]benzodiazepine (PBD) derivatives possess cancerostatic and anti-infective properties thus making them candidates of possible antibacterial agents. ²-lactam antibiotics are vital weapons for the treatment of bacterial infections, but their existence and effectiveness has been faced with resistance from ²-lactamases. Therefore, the need for new effective antimicrobial drugs is very crucial. In this work, we synthesized in high yields, PBD analogs 1−3, 5 and 7−9 in three to four synthetic steps from commercially available L-proline and isatoic anhydride. MTT Assay was employed to test the in vitro cytotoxicity of PBD analogs 1, 2, 5 …

Multilevel Models For Longitudinal Data, Aastha Khatiwada

Electronic Theses and Dissertations

Longitudinal data arise when individuals are measured several times during an ob- servation period and thus the data for each individual are not independent. There are several ways of analyzing longitudinal data when different treatments are com- pared. Multilevel models are used to analyze data that are clustered in some way. In this work, multilevel models are used to analyze longitudinal data from a case study. Results from other more commonly used methods are compared to multilevel models. Also, comparison in output between two software, SAS and R, is done. Finally a method consisting of fitting individual models for each …

Characterization Of Sip470, A Family 1 Lipid Transfer Protein And Its Role In Plant Stress Signaling, Timothy Ndagi Audam

Electronic Theses and Dissertations

SIP470, a putative tobacco lipid transfer protein, was identified in a yeast two-hybrid screen to interact with SABP2. SABP2 is a critical role in SA-mediated signaling in tobacco and other plants. In vitro studies using purified recombinant SIP470 confirmed that it is a lipid binding protein. In an attempt to determine its role in mediating stress responses, Arabidopsis T-DNA insertion knockout lines lacking SIP470 homolog were used for the analysis. These mutant plants were defective in basal resistance against microbial pathogens. Expression of defense gene PR-1 was also delayed in these mutant plants. Interestingly, these mutant plants were not defective …

Synthesis And Characterization Of Imidazolo 3,1- Tetrakis (N-Phenylacetamidato) Dirhodium (Ii) And A Crystallographic Study Of A Copper And Two Molybdenum Model Cofactors, Gabriel I.G. Thompson

Electronic Theses and Dissertations

Imidazole was reacted with 3,1-tetrakis (N-phenlyacetamidato) dirhodium (II) to explore the chemistry of asymmetric dirhodium catalysts. The imidazolo 3,1-tetrakis (Nphenlyacetamidato) dirhodium (II) complex was synthesized and then characterized by Nuclear Magnetic Resonance and Ultraviolet-Visible spectroscopies as well as by single crystal X-ray Diffraction. Additionally, one copper and two molybdenum model cofactors were characterized by XRD to better understand their structure/function relationships. NMR results gave evidence of the formation of the 3,1-imidazole complex, and UV-Vis indicated that even in large excess imidazole was coordinated only to one axial site. The structure of the 3,1-imidazole complex was confirmed by XRD with the …

Characterization Of Pro-Inflammatory And Anti-Inflammatory Microglia In The Anterior Cingulate Cortex In Autism Spectrum Disorder, Aubrey N. Sciara

Electronic Theses and Dissertations

Autism spectrum disorder (ASD) is associated with functional abnormalities of the anterior cingulate cortex (ACC), a brain area that mediates social behavior. Given evidence of a role of inflammation in ASD, markers of pro-inflammatory and anti-inflammatory microglia were studied using postmortem ACC tissues from ASD and age-matched typically developed control donors. Gene expression levels of pro-inflammatory (CD68, HLA-DRA, IL1B, NOS2, PTGS2) and anti-inflammatory (ARG1, IGF1, MRC1, PPARG) microglial genes were measured using quantitative real-time PCR. Additionally, brain sections were immunohistochemically stained for a microglial marker. Expression levels of IGF1 were modestly higher, while the expression of …

Venom Peptides Lasioglossin Ii And Mastoparan B As Escherichia Coli Atp Synthase Inhibitors, Rafiat Ajoke Bello

Electronic Theses and Dissertations

The inhibitory effects on Escherichia coli ATPase activity by two venom peptides, lasioglossin II and mastoparan B. Membrane bound F₁F_O ATP synthase was isolated from E. coli strain pBWU13.4/DK8 and treated with varied concentrations of lasioglossin II and mastoparan B. Lasioglossin II caused very low inhibition of ATPase activity, but the inhibition profile of mastoparan B was suggestive of an interesting biological effect. A relatively shorter total length, a smaller net positive charge, and a reduced amphipathic character of both peptides, as compared to previously tested antimicrobial peptides, may account for the limited degree of inhibition observed …

Exploring Protective Factors Among Lesbians, Gays, And Bisexuals: A Framework For Psychological Well-Being And Relative Influence, Sheri Laduke

Electronic Theses and Dissertations

Lesbian, gay, and bisexual individuals must regularly navigate stigma, or social situations in which they are devalued because of their sexual orientation. The research has well established minority stress processes which link situations of stigma to reports of poor psychological well-being. However, protective factors leading to healthy psychological well-being are relatively understudied. This dissertation is a review of protective factors that have already emerged in the research and an assessment of these protective factors simultaneously to better understand how they influence psychological well-being. I recruited adult sexual minority participants using a comprehensive social media approach. I then tested mastery, problem-solving …

Classroom Environment: Content Analysis Examining Characteristics Of Classroom Environments That Affect Students' Academic Achievement, Lucinda Shaddock Bellamy

Electronic Theses and Dissertations

The purpose of this qualitative study was to extend the understanding of the characteristics of a classroom environment that impact students’ engagement in academics and therefore has the potential to positively impact student achievement scores. Data were collected through content analysis to analyze for reoccurring themes to assess how the characteristics of the classroom environment impact student’s achievement. Ten classrooms within the Kingsport City District were observed and analyzed for this study.

Six research questions guided this study, and qualitative data were analyzed for reoccurring themes. Findings from this study suggest that implementing certain characteristics in to the classroom environment …

Effect Of A Recovery Supplement On Weight Lifting Performance, Muscle Fiber Morphology And Muscle Protein Accretion, Christopher B. Taber

Electronic Theses and Dissertations

The purposes of this dissertation were to examine the effect of a protein and carbohydrate recovery beverage versus a placebo on weightlifting performance, its effect on muscle morphological changes and specific muscle protein accretion. The following are major finding from the dissertation: 1) Protein and carbohydrate recovery supplementation does not appear to have influence on performance measure in trained weightlifters. This finding may be associated with the short-term nature of this study and the trained population used. 2) Compared with placebo, a protein and carbohydrate beverage provided greater benefits on cross sectional area of type I and type II muscle …

Silver-Polymer Nanocomposites, Anita N. Paul

Electronic Theses and Dissertations

The objective of this research was the development of an efficient method for the preparation of silver-polymer nanocomposites containing finely dispersed silver nanoparticles. The surface of nanosilver was functionalized by thiolation with 2-aminoethanethiol. Amino-modified nanosilver was covalently bonded to polyacrylic acid, biodegradable polymers like acid terminated polylactic acid, ester terminated poly(DL-lactide-co-glycolide) and acid terminated poly(DL lactide-co-glycolide) in the presence of diisopropylcarbodiimide by carbodiimide method. Esterification of the carboxyl groups of Ag-polyacrylic acid by hydrochloric acid in methanol resulted in the formation of a stable colloidal dispersion of Ag nanoparticles in the polymer matrix. It was observed that not just acid …

Exploring The Relationship Between Behaviour And Neurochemistry In The Polyphenic Spider, Anelosimus Studiosus (Araneae: Theridiidae), Jennifer B. Price

Electronic Theses and Dissertations

The importance of social behaviour is evident in human society, but there are both costs and benefits associated with cooperation and sociality throughout the animal kingdom. At what point do the benefits outweigh the costs, and when do selective pressures favour sociality and colonization over solitude and independence? To investigate these questions, we have focused on an anomalous species of spider, Anelosimus studiosus, also known now as the northern social spider. Throughout its broad range, A. studiosus is solitary and aggressive, but recently, colonies of cooperative and social individuals have been observed at northern latitudes. This leads to two …

Endothelial Hspa12b Is A Novel Protein For The Preservation Of Cardiovascular Function In Polymicrobial Sepsis Via Exosome Mir-126, Xia Zhang

Electronic Theses and Dissertations

Sepsis is the most frequent cause of mortality in most intensive care units. Cardiovascular dysfunction is a major complication associated with sepsis, with high mortality rates up to 70%. Currently, there is no effective treatment approach for sepsis.

The integrity of the endothelium is fundamental for the homeostasis of the cardiovascular system. Sepsis induces endothelial cell injury which is the key factor for multiple organ failure. The increased expression of adhesion molecules and chemokines in endothelial cell promotes leukocytes infiltration into the tissue. The loss of tight junction proteins and increased permeability of the endothelial cells will provoke tissue hypoxia …