Medicine and Health Sciences Commons^™

A Comparison Of Flexural Fracture Of Three Different Nickel-Titanium Rotary File Systems, Matthew Warren Lloyd

Theses and Dissertations

The purpose of this study was to compare the number of rotations to failure of three different rotary file systems. ProFile, Sequence, and Liberator files in sizes 25 and 40 with 0.04 taper were divided into groups of five and rotated against a grooved metal block mounted to a Universal testing machine at 31 and 34 degrees. Each file was rotated at 300 rpm until fracture occurred. The number of rotations to fracture were calculated. Use of a three-way ANOVA and Tukey's HSD multiple comparison tests revealed significant differences for the angle of deflection, size, and type of file. An …

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 …

The Substituted Pyrrole Jb-03-14 Induces Autophagic Cell Death And Growth Arrest In Breast Tumor Cells, Christopher Ryan Arthur

Theses and Dissertations

The use of chemotherapy in the treatment of cancer has stimulated the demand for better chemotherapeutic agents that are more potent at destroying tumor cell populations and more selective for the specific tumor versus normal host tissues. This project is directed at discovering new anti-tumor agents that are effective against breast cancer based on structures derived from marine organisms, specifically brominated pyrroles. We utilized an in vitro breast cancer model to study the effects of pyrroles on tumor proliferation and survival, as well as growth arrest and cell death. Our findings indicate that the substituted pyrrole JG-03-14 induces time dependent …

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 …

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 …

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. …

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 …

The Effect Of A Nominal Fee On Treatment Choices For Children Needing Dental Rehabilitation, D'Audra M. Cole

Theses and Dissertations

Objective: The purpose of the study was to determine if a co-payment resulted in a differential preference for general anesthesia (GA) or oral sedation (OS) and, if so, to examine whether age, the number of appointments, perceived risks of treatment, child's awareness during treatment, or insurance type appeared to play a role in this preference.Methods: Using a cross-sectional survey design, questionnaires were distributed to caregivers of patients in the waiting room of the Virginia Commonwealth University Pediatric Dental Clinic. Two different questionnaires were distributed randomly. Both surveys described a scenario with the need for dental treatment under general anesthesia (GA) …

The Quantitative Genetics Of Neurodevelopment: A Magnetic Resonance Imaging Study Of Childhood And Adolescence, James Eric Schmitt

Theses and Dissertations

Understanding the causes of individual differences in brain structure may give clues about the etiology of cognition, personality, and psychopathology, and also may identify endophenotypes for molecular genetic studies on brain development. We performed a comprehensive statistical genetic study of anatomic neuroimaging data from a large pediatric sample (N=600+) of twins and family members from the Child Psychiatry Branch at the NIMH. These analyses included variance decomposition of structural volumetric endophenotypes at several levels of resolution, voxel-level analysis of cortical thickness, assessment of gene by age interaction, several multivariate genetic analyses, and a search for genetically-mediated brain-behavioral relationships. These analyses …

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 …

Anesthesia Clinical Performance Outcomes: Does Teaching Methodology Make A Difference?, Nina E. Mclain

Theses and Dissertations

Researchers have studied memory recall of crisis-oriented or emotional events in non-educational settings. However, within the health care field, there has been a limited study of the the concept of recall of crisis oriented or emotional events in& health care education. Crisis-oriented events such as natural disasters, acts of bioterroism, and industrial accidents, have been reported to impact memory. Patient safety is a primary focus in anesthesia education, appropriate crisis management is imperative to quality anesthesia care. Due to the critical nature of anesthesia delivery, there is a strong, constant need to develop methods that will enhance, support, and improve …

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 …

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 …

Vocational Rehabilitation Of Clients With Brain Injury: An Investigation Of Racial Disparity Within The Rehabilitation Services Administration (Rsa) 911 Database, Stephanie A. Kolakowsky-Hayner

Theses and Dissertations

Finding and maintaining employment is an ongoing problem for persons with disabilities, especially those with brain injuries. State vocational rehabilitation agencies are the primary authority responsible for providing employment-related services for individuals with disabilities throughout the United States. Little effort has been committed to identifying disparities in health and rehabilitation services provided to Americans with disabilities, particularly those with brain injuries. The purpose of this investigation was to utilize Aday and Andersen's Framework for the Study of Access to examine racial disparity within the Rehabilitation Services Administration 911 Database, and thus the vocational rehabilitation system, among clients with brain injury. …

An Examination Of The Relationships Among Health Literacy, Social Support, And Patient Activation In Community Residing Older Adults, Brenda L. Harding Hage

Theses and Dissertations

This study examined the relationships among the variables health literacy, social support, and patient activation. The subjects were 90 elderly, community residing adults meeting the inclusion criteria and who volunteered to participate in the study and completed three survey instruments: the Short Form of Functional Health Literacy (Parker, Baker, Williams & Nurss, 1995); the Medical Outcomes Survey (MOS) Social Support Survey Instrument (Sherboume & Stewart, 1991); the Patient Activation Measure (PAM) Short-Form (Hibbard, Mahoney, Stockard, & Tusler, 2005); and a demographic form.

A correlational design was used to test the hypotheses that social support and health literacy are positively related …

Stress And Anxiety In Adhd: Links To Sensory Over-Responsivity, Stacey E. Reynolds

Theses and Dissertations

Sensory Modulation Dysfunction (SMD) is characterized by an inability to consistently and accurately grade responses to sensory information. SMD, and specifically sensory over-responsivity (SOR), has been correlated with stress and anxiety in some developmentally delayed populations and has been associated with structures and functions of the hypothalamic-pituitary adrenal (HPA) axis. Recent attention has been given to HPA functioning in children with Attention Deficit Hyperactivity Disorder (ADHD), with a majority of studies identifying blunted or diminished cortisol patterns. In contrast, elevated cortisol has been associated with anxiety and anxious behaviors in both animal and human studies. The purpose of this study …

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. …

Supporting Personhood In Dementia: Examining The Impact Of Volition On Function In Everyday Occupations, Christine L. Raber

Theses and Dissertations

Understanding volition and preferences for occupation is a critical underpinning of effective occupational therapy services that promote and preserve identity for persons with moderate dementia. Although it has been posited that this population has significant difficulty expressing volition for daily occupations, little research has examined the role of volition in guiding engagement in occupations. This phenomenological study provides an in-depth description and analysis of volition in eight persons with moderate dementia. Guiding questions related to understanding patterns of past life interests, outward demonstration of volition, volitional continuity. and the relationship of the social environment to volition and engagement in daily …

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 …

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 …

Characterization Of The Factors Associated With Sccmec Mobility In Staphylococcus Aureus, Michael James Noto

Theses and Dissertations

The gene encoding resistance to β-lactam antibiotics in the staphylococci is found on the chromosome in a genomic island designated Staphylococcal Chromosome Cassette mec or SCCmec. In addition to the resistance gene, mecA, SCCmec also contains site specific recombinase genes, ccrAB, that are capable of catalyzing the chromosomal excision and integration of SCCmec. The increasing prevalence of methicillin-resistant Staphylococcus aureus infections may be due, in part, to the transfer of SCCmec into successful methicillin-sensitive S. aureus lineages. In this work we attempt to better characterize the factors associated with SCCmec transfer, beginning with CcrAB-mediated SCCmec excision in a collection of …

Improving Life Satisfaction Of Elders Through Oral History: The Narrator's Perspective, Mary B. Ligon

Theses and Dissertations

Oral history is a method of preserving historical information through in-depth interviews. Because the process requires narrators to use remote recall while sharing their life experiences, it can also be considered a reminiscence-related activity. Before this study, the positive effects on narrators of providing an oral history were noted in the research literature but had not been evaluated through quantitative methods. Based on theoretical constructs of Erikson and Butler, it was hypothesized that participation in oral history interviews would improve the life satisfaction of narrators. Life satisfaction was operationalized and measured using the Life Satisfaction Index Version A (LSIA). The …

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 …

Impact Of Combat Stress On Mental Health Outcomes: Brfss Survey Data 2006, Emily Pedneau

Theses and Dissertations

Objectives: This study sought to determine the relationship between combat experience and mental health outcomes. The study sought to determine whether age was a significant factor in poor mental health outcomes. Methods: Multiple logistic regression (n = 195,048) and multiple linear regression (n = 264,154) were performed on the 2006 Behavioral Risk Factor Surveillance System (BRFSS) survey. Veteran status and a host of demographic and health status questions were analyzed in relation to diagnosis of anxiety or depressive disorder (multiple logistic regression) and to number of days poor mental health (multiple linear regression). Results: Diagnosis of anxiety or depression was …

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 …

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 …

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 …

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.