Medicine and Health Sciences Commons^™

Identification And Characterization Of Helper Phage Gene Products Involved In Mobilization Of Staphylococcal Pathogenicity Island Sapi1, Sandra Mckenzie Tallent

Theses and Dissertations

Staphylococcal pathogenicity island SaPI1 is excised from genomic DNA and extrachromosomal copies are amplified during the vegetative growth of staphylococcal phage 80α. The amplified genetic element is subsequently encapsidated and transduced at very high frequency. Previous studies have demonstrated that the transducing particles have virions with tails that appear identical to those of helper phage 80α but have smaller capsids, commensurate with the smaller genome of the SaPI (Lindsay et.al., 1998). The morphology of the transducing particles, coupled with the observation that the genomic sequence of SaPIl (GenBank U93688) does not reveal any obvious phage structural proteins, has led to …

Telomerase Inhibition And Sensitization Of Breast Tumor Cells, Kennon R. Poynter

Theses and Dissertations

Telomerase, a ribonucleoprotein enzyme minimally composed of an RNA template (hTR) and a catalytically active protein subunit (hTERT), synthesizes telomeric repeats onto chromosome ends and is obligatory for continuous tumor cell proliferation, as well as malignant progression of breast cancer cells. Telomerase is an attractive anticancer therapeutic target because its activity is present in over 90% of human cancers, including more than 95% of breast carcinomas, but undetectable in most somatic cells. Traditions chemo- and radio-therapies lack the ability to effectively control and cure breast cancer, in part because residual cells are or become resistant to DNA damaging modalities.While various …

Sodium Hypochlorite's Effect On Nickel-Titanium Rotary Instruments And Its Effect On Resistance To Fracture, Michael Shane Smith

Theses and Dissertations

The purpose of this study was to examine the effect of partial and total immersion in sodium hypochlorite on nickel-titanium rotary files and to determine whether resistance to fracture was influenced by the immersion time. One hundred K3™ and 100 ProFile® rotary files were either partially or totally immersed in 5.25% sodium hypochlorite for zero, one, five, thirty, or sixty minutes. After immersion, files were subjected to cyclic fatigue testing. Time to fracture was recorded and analyzed by a two-way ANOVA. Tukey's honest significant difference was used to identify any differences in immersion times. Within all ProFile groups and partial …

Novel Sulfated 4-Hydroxycinnamic Acid Oligomers As Potent Anticoagulants, Brian Lawrence Henry

Theses and Dissertations

The occurrence of thrombosis in several pathophysiological conditions creates a huge need for anticoagulation therapy. Thrombin and factor Xa have been prime targets for regulation of clotting through the direct and indirect mechanism of inhibition. This work investigates chemo-enzymatically prepared oligomers of 4-hydroxycinnamic acids (DHPs) as potential anticoagulants. Oligomers were prepared through peroxidase-catalyzed oxidative coupling of 4-hydroxycinnamic acids. The products resulting from this reaction are called CDs, FDs and SDs. Structurally, these sulfated DHPs are unique and do not resemble any of the anticoagulants known in the literature.DHP oligomers were found to increase clotting times at concentrations comparable to heparin. …

Obesity As A Risk Factor For Preeclampsia: Role Of Inflammation And The Innate Immune System, Tanvi Jayendra Shah

Theses and Dissertations

Obesity is a known risk factor for preeclampsia, but the reason for this risk is unknown. We sought to demonstrate how obese individuals are predisposed to preeclampsia by mechanisms involving inflammation and the innate immune system. First, we used immunohistochemical studies to identify neutrophil infiltration, NF-κB activation and COX-2 expression in vascular tissue of obese women. We then demonstrated similar neutrophil infiltration and vascular inflammation in preeclamptic women.We used in vitro experiments to test if neutrophils and their products, reactive oxygen species (ROS) and tumor necrosis factor-alpha (TNFα) can activate NF-κB and cause expression of its inflammatory products, COX-2, thromboxane …

The Utility Of Depression Screening Measures After Traumatic Brain Injury, Amy H. Riddick

Theses and Dissertations

Objectives: Identifying reliable, practical and easy to use tools to assess depression in patients with traumatic brain injury (TBI), is a necessary first step to addressing a high incidence problem. The intention of this study is to validate depression screening measures with a criterion-based structured interview among people with TBI. The final outcome will identify which measure is the best indicator of depression diagnosis in this population. Methods: 112 participants with TBI were administered the Beck Depression Inventory (BDI), Neurobehavioral Functioning Inventory (NFI), The Hamilton Rating Scale for Depression (Ham-D), and the Structured Clinical Interview for DSM-IV TR Axis I …

Trend Analysis Of Automobile Collision Amongst 15-19 Year Olds In Virginia, 2000-2004, Imo F. Ndem

Theses and Dissertations

Purpose. This research study on automobile collision in Virginia amongst fifteen to nineteen (15-19) year olds looked into the trend analysis over a five (5) year period of 2000 to 2004. Trend analysis is usually done for aggregates of all injuries—either intentional or unintentional injuries, or both. The primary objective of this research study was to examine the trend in hospitalization rates and mortality rates for males and females independently. It further looked into the trend, if any, in hospitalization rates, mortality rates, and case-fatality rates, for both males and females combined. The different Tables illustrate the extent and the …

Transition From Health Maintenance Organizations To Consumer Driven Health Plans: Measurement Of Initial Impacts For Members With Chronic Conditions, Carl F. Goff

Theses and Dissertations

New consumer driven health insurance products are designed to contain health care costs by making consumers more accountable for the care they receive through being responsible for more cost sharing, making decisions regarding health care providers they will use, and increasing exposure to and use of health information for services and providers. Potential benefits of consumer driven products include increased information regarding personal health and a more knowledgeable patient base. Potential drawbacks of consumer driven products include negative impacts on consumers with chronic and complex health conditions.

The purpose of this study was to ascertain differences in health services utilization …

Examination Of Birth Outcomes With Mode Of Delivery For Breech Presentation, Kelly Marie Arey

Theses and Dissertations

Introduction: Approximately 3% to 4% of all pregnancies at term will have a fetus with a breech presentation. Studies have shown that the US has almost completely abandoned vaginal delivery for breech presentation through the influence of the "Term Breech Trial" (TBT) which concluded that a policy of planned caesarian section would reduce perinatal mortality, late neonatal mortality, and serious neonatal morbidity by approximately two-thirds for term fetuses. However, the recommendations are still being challenged by others.Objectives: The purpose of the study was to describe who in Virginia is having a vaginal delivery for a breech presentation and to determine …

Self-Care And Quality Of Life In Patients With Heart Failure, Chantira Chiaranai

Theses and Dissertations

Although it is well known that self-care reduces the frequency of hospital admissions and exacerbations and enhances quality of life (QOL) in heart failure (HF) patients, little is known about self-care in this population. Therefore, the study purpose was to examine relationships among selected individual characteristics (demographics, severity of illness, comorbidities, and social support), self-care strategies, and QOL using Reigel's Model of Self Care in Patients with Heart Failure as the guiding framework. In this descriptive correlational study, self-care was measured using the Self-Care of Heart Failure Index (SCHFI), which measures self-care maintenance (SC-Mt), self-care management (SC-Mn), and self-care self-confidence …

An Invitro Leakage And Viscosity Analysis Of Root End Filling Materials, Paul D. Clark

Theses and Dissertations

The purpose of this study was to determine if the viscosity of MTA Angelus Fluid is lower than that of Pro Root MTA and MTA Angelus; and to compare the viscosity, leakage and particle size of these materials to determine whether a relationship exists between these properties. The viscosity of each material was measured and compared with the Student's t test. MTA Angelus Fluid's viscosity was significantly lower than the other two materials tested. Microleakage of root end fillings was assessed in a passive diffusion model. Leakage groups were compared with a one-way ANOVA (p < 0.05). No significant difference was found. Particle size and shape were evaluated with the SEM. MTA Angelus Fluid has a lower viscosity than the other materials tested. There was no significant difference in the sealing ability of the three materials tested and there was no apparent variation in each material's particle size or shape.

Cannabinoid Modulation Of Chemotaxis Of Macrophages And Macrophage-Like Cells, Erinn Shenee Raborn

Theses and Dissertations

Exogenous and endogenous cannabinoids have been reported to modulate functional activities of macrophages. It is recognized that macrophages express primarily the CB2 cannabinoid receptor, but recent studies indicate that its expression is differential in relation to activation state with maximal levels occurring when cells are in "responsive" and "primed" states. The functional activities of macrophages when in these states of activation are the most susceptible to the action of cannabinoids, at least in terms of a functional linkage to the CB2. To assess the effect of cannabinoid treatment on macrophage chemotaxis and test the hypothesis that cannabinoids inhibit the chemotactic …

A Comparision Of Delta-9-Tetrahydrocannabinol Dependence In C57bl/6j Mice And Fatty Acid Amide Hydrolase Knock Out Mice, Brittany Leigh Alice Carlson

Theses and Dissertations

The idea that humans and laboratory animals can become physically dependent on marijuana or its primary psychoactive constituent, delta-9-tetrahydrocannabinol (THC), is gaining acceptance. However, there are no currently approved pharmacotherapies to treat cannabinoid withdrawal. The objective of this thesis was to evaluate whether elevating endogenous anandamide levels using mice lacking fatty acid amide hydrolase (FAAH), the enzyme responsible for anandamide metabolism, would ameliorate THC dependence. Mice were treated subchronically with a low or high THC dosing regimen and challenged with the CB1 receptor antagonist, rimonabant, to precipitate withdrawal. Following subchronic THC treatment, rimonabant precipitated a significant increase in paw flutters …

Determinants Of Obesity: Racial Differences, Nikkia L. Goforth

Theses and Dissertations

BACKGROUND: Obesity is a major public health problem. Studies have shown that there are racial and ethnic differences in the prevalence of obesity. However, there is limited research that examines the effects of sedentary and poor lifestyle behaviors and obesity among different racial and ethnic groups. Furthermore, most studies focus on the problem of obesity among children. This study was conducted to examine racial differences in determinants of obesity in adults in the United States. METHODS: Data from the 2005 Behavioral Risk Factor Surveillance System was used for this analysis. Demographics, lifestyle behaviors, and existence of chronic diseases were assessed. …

On The Binding Of N1-Substituted Tryptamines At H5-Ht6 Receptors, Abner Nyamwaro Nyandege

Theses and Dissertations

Serotonin was first discovered in the late 1940s as a vasotonic factor and is now considered a principal neurotransmitter in the nervous system. 5-HT6 receptors are one of the most recently identified members of the serotonin receptor family which consists of seven classes (5-HT1-5-HT7). 5-HT6 receptors are G-protein coupled, positively coupled to an adenylate cyclase second messenger system and are primarily found in the central nervous system (CNS). The exact functional role of 5-HT6 receptors has not been determined, but is implicated to have possible involvement in certain neuropsychiatric disorders and cognition. To investigate the functional role of these receptors, …

Adverse Anesthesia Outcomes: A Retrospective Study Of An Ambulatory Surgical Center Versus A Dental Office Setting, Gaurav Agarwal

Theses and Dissertations

Purpose: The purpose of this study was to compare the adverse events that occur with general anesthesia for dental rehabilitation between a hospital setting and dental clinic setting. Methods: A retrospective chart review was performed examining patients who had received dental rehabilitation with general anesthesia at the Virginia Commonwealth University Department of Pediatric Dentistry. Subjects were either treated in the Pediatric Dental Clinic or the Hospital Ambulatory Surgery Center (ASC) from July 2005 to December 2006. Anesthesia records of induction, intubation, maintenance, emergence and recovery were compared between the two settings.Results: There were a total of 422 charts reviewed with …

Analgesic Use In U.S. Emergency Departments For Patients Reporting Moderate To Severe Pain: Diagnosis And Select Patient Characteristics Influencing Narcotic Analgesic Prescribing Practices, Hassan Zakaria

Theses and Dissertations

Objective: This study aims to examine the relationship between emergency department patient encounter characteristics and narcotic analgesic prescribing practices in order to determine what patient characteristics, if any, influence the decision to prescribe narcotics.Methods: Cross sectional data on patients presenting to U.S. emergency departments from the 2003 and 2004 National Hospital Ambulatory Medical Care Survey were analyzed. Patients reporting moderate to severe pain were included in the sample and analysis. Chi square tests of significance were used to assess the association between individual demographic and encounter characteristics to narcotic prescription or administration. Separate multiple logistic regressions were then performed on …

Effects Of Ankle Support On Time To Stabilization Of Subjects With Stable Ankles, Raquel Elise Martin

Theses and Dissertations

The purpose of this study was to determine if prophylactic ankle tape and/or ankle braces improve dynamic stability in TTS measure. All subjects were healthy and had no prior history of ankle injuries. Data collection consisted of each subject performing a single leg jump-landing with ankle tape, ankle brace, combination of the two, and control (no tape or brace) conditions. Dynamic stability was assessed with time to stabilization force plate measure. Significant plane by ankle tape interaction (p=0.045) was found. No significant plane by ankle tape by ankle brace interaction (p=0.637), no significant ankle tape by ankle brace interaction (p=0.483), …

Children With Special Needs Oral Health Quality Of Life Survey, Kristin Elizabeth Nelson

Theses and Dissertations

Purpose: The purpose of this study was to asses the oral health quality of life of children with special health care needs. This study examined the effects of oral health conditions on general well-being and family life of these children. A secondary aim of the study was to investigate correlations between specific health care conditions, gender, and age of these children and their global ratings of oral health and well-being.Methods: This study was a cross-sectional design with subjects who are members of the Virginia Care Connection for Children program, based at Virginia Commonwealth University. The oral health quality of life …

The Role Of Inhibitory Interneurons In A Model Od Developmental Epilepsy, Patrick James Wolfgang

Theses and Dissertations

Epilepsy, defined by recurrent seizures, is the one of the most prevalent neurological disorders worldwide (World Health Organization 2007). While many forms of epilepsy are well-controlled by anti-epileptogenic medications, a significant portion of patients have intractable, i.e. untreatable, seizures. The etiology of these seizures is varied, but a significant cause, particularly for patients with intractable epilepsy is developmental malformation. In these cases, an error or interruption during the development of the neocortex produces a structural alteration. Such patients may have other neurological problems, but seizures are the most common symptom. The neuronal mechanisms that link malformation and cortical hyperexcitability are …

The Effect Of Income Level On The Relationship Between The Personal Support Matrix And Sustained Breastfeeding, Sandra Mann Gossler

Theses and Dissertations

The Healthy People 2010 Objectives for the population of the United States include the objective for women to sustain breastfeeding at a higher rate than they are currently.The American Academy of Pediatrics (AAP) now recommends that all infants be fed human milk for the first year of life instead of the previously recommended first six months of life. Breastfeeding initiation rates are rising, but breastfeeding duration rates continue to fall. It was hypothesized that the support system of the women may play a role in the duration of breastfeeding. The purpose of this research study was to investigate the support …

Breast And Cervical Cancer Screening In Virginia: The Impact Of Insurance Coverage And The Every Woman's Life Screening Program, Kamila Somayaji

Theses and Dissertations

Background: Screening for breast and cervical cancers is important because early detection increases cancer survival. Since 1991, the U.S. government has helped finance a national early detection program for breast and cervical cancer among uninsured low-income women, known in Virginia (VA) as Every Woman's Life (EWL).Objectives: This study aims to determine whether there are differences in the prevalence of breast and cervical cancer screening based on insurance coverage, assess the prevalence of screening by health district, and evaluate the ability of EWL to effectively reach its target population.Methods: Cross-sectional data from the 2005 Behavioral Risk Factor Surveillance System survey were …

Overbite Correction And Smile Esthetics, Kevin Erick Kelleher

Theses and Dissertations

The purpose of this prospective clinical study was to investigate differences in outcomes from two common treatment modalities used to reduce deep overbite: maxillary incisor intrusion using an intrusion arch and posterior tooth eruption using an anterior bite plate. Pre-treatment, post-overbite correction and post-treatment records were gathered from 32 patients who presented with deep overbite malocclusions to the Virginia Commonwealth University orthodontic clinic. Both groups of patients experienced reductions in overbite and maxillary incisor display as well as maxillary and mandibular incisor proclination and mandibular incisor occlusal movement during treatment. In the intrusion arch group, the center of resistance of …

Disparities In The Use Of Emergency Contraceptives, Rebecca Dallman

Theses and Dissertations

Purpose: Unintended pregnancies are often a burden to pregnant women and to the health care system. The rates of unintended pregnancies have decreased since the wide use of contraceptives has increased; however, young women, women with low income, and racial/ethnic minorities are more likely to use contraceptives inconsistently, which increases the risk of an unintended pregnancy. This risk could be reduced with the proper use of emergency contraceptives (ECs).Methods and Analysis: A cross-sectional study was conducted using the data from the female respondents of the 2002 Cycle 6 NSFG. Logistic regression was used to determine rates of use of ECs …

Visual Contributions To The Vestibulo-Ocular Reflex During Balance Recovery Tasks, Mark D. Diehl

Theses and Dissertations

Introduction: The Vestibulo-ocular reflex (VOR) is quantified by computing the ratio of head angular velocity and eye angular velocity (VOR Gain). This measure only includes head angular movements; linear translations are not accounted for. These investigations postulate an alternative method of VOR quantification, one that assesses retinal image stability during head angular and linear movements (Foveal fixation (FF)). This method was used to assess the role of vision in balance reactions. Methods: Experiment 1 : Ten Young subjects were fitted with an eye tracker linked to an EM kinematic recording system. This allowed for the recording of head, trunk and …

Resilience And Risk-Taking Behavior Among Thai Adolescents Living In Bangkok, Thailand, Patcharin Nintachan

Theses and Dissertations

The major purposes of this study were to determine the relationships among resilience, risk-taking behavior and personal characteristics of Thai adolescents living in Bangkok and to examine the differences in risk-taking behavior by school grades or gender. To accomplish these, a cross-sectional correlational research design was conducted. Resilience was measured by using the State-Trait Resilience Inventory developed by Hiew, Mori, Shirnizu and Torninaga.Risk-taking behavior was measured by the Risk-taking Behavior Questionnaire for Thai Adolescents which is a modified version of the 2003 Youth Risk Behavior Survey (YRBS) originally developed by the U.S. Centers for Disease Control and Prevention. In order …

Interactions Of Mtfabh With Its Substrates And Inhibitors Reveal Novel Mechanistic Insights, Sarbjot Singh Sachdeva

Theses and Dissertations

Tuberculosis emerged from its grave to be one of the deadliest diseases of the present time after recently developing a synergy with AIDS. A fatty acid condensing enzyme-mtFabH has been proposed to connect the key processes involved in biosynthesis of mycolic acids, an important component of mycobacterial cell wall. It condenses long acyl Coenzymes A (CoA; up to C20CoA) with malonyl Acyl Carrier Protein (ACP) to form the elongated β-ketoacyl-ACP which further undergoes rounds of elongation to form mero-mycolate branch of mature mycolic acids. Owing to its proposed central position in mycolic acid synthesis, mtFabH has attracted considerable attention as …

Has Richmond, Virginia Become Safer In The Past Five Years (2002-2006)?: An Analysis Of Ambulance Data Regarding Penetrating Trauma Incidents, Ashleigh K. Mccabe

Theses and Dissertations

Introduction: The World Health Assembly declared violence as a worldwide public health problem. Homicides have been identified as a leading cause of death in the United States across all age groups. The national homicide rate for 2004 and 2005 are 5.5 and 5.6 per 100,000 population, respectively. The reported rates for Virginia are 5.2 (2004) and 5.6 (2005) per 100,000 population, showing a 16.9% increase. Richmond has been ranked as high as the sixth most dangerous among similar cities in the United States. This study examines penetrating trauma injuries identified through 9-1-1 calls as an indicator of the incidence of …

A Survey On The Usage Of Articaine Among General And Pediatric Dentists, Robert Louis Hollowell Iii

Theses and Dissertations

Purpose: The purpose of this study is to determine the impact that the introduction of articaine has had on local anesthetic selection by general and pediatric dentists for use in three different age groups of children.Methods: Using a cross sectional survey design, a questionnaire regarding the use of local anesthetics in children was mailed to a random sample of 500 general dentists from North Carolina, 500 general dentists from Virginia, and all 230 pediatric dentists from North Carolina and Virginia. The 16-item questionnaire included questions regarding the preferred local anesthetic to use in three different age groups, 2-3 years of …

Immunohistochemical Study Of Phenotypes Of Dendritic Cells In Dental Pulps From Non-Carious And Carious Teeth, Melissa A. Harmon

Theses and Dissertations

Mature dendritic cells (DCs) in inflamed tissues may promote inflammation but the status of DCs in pulpitis is not known. We hypothesized that DC maturation would correlate with carious lesion depth and that CD4+ cells would be found in association with mature DCs. Pulps were collected from teeth exhibiting: (I) no caries (n=9), (II) shallow dentinal caries (n=5), and (III) deep caries (n=9). Pulpal tissues were cryo-sectioned and positive cells were examined with immunohistochemistry, Mature DCs (CD83+) were almost exclusively restricted to pulps from deep caries. Furthermore, CD209+ DCs in deep caries were elevated over other groups and CD209+ cells …