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 …

The Association Between Adult Self-Reported Asthma & Potential Exposures To Asthma Triggers In Virginia Workplaces: An Ecological Study, Jeanette R. Bowman

Theses and Dissertations

Introduction: Work-related asthma (WRA) is thought to be the most common occupational lung disease in the U.S., but there is no standard case definition of WRA. Most states, including Virginia, do not require WRA diagnoses to be reported to health departments. At present, there is too little epidemiological data on WRA in Virginia to direct public health planning efforts. Objectives: The first objective of this study was to estimate potential exposure to workplace asthma triggers in each of Virginia's 35 health districts. The second objective was to examine associations at the health district level between workplace asthma triggers, other asthma …

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 …

The Effect Of Pediatric Hospital Specialization On Patient Safety And Effectiveness Of Care, James Mitchell Harris Ii

Theses and Dissertations

Provider specialization is an area of interest in health care as patients, payers and policy makers are now demanding better performance and demonstrated proof of the benefits of specialization. While previously ignored in the specialization debate, now even the hospitals focusing on pediatric care (i.e. children's hospitals) are experiencing pressure to demonstrate their value. The current study attempts to answer the questions: do hospitals specializing in pediatric care provide better quality pediatric inpatient care; and do they do so for differing types of patient outcomes and across different levels of care complexity? Contingency Theory is used to develop and assess …

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 …

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) …

Oral Health Services In A Medical Setting, Robert William Mansman Ii

Theses and Dissertations

Purpose: The purpose of this study is to examine the baseline oral health status of infants and the level of their caregiver's oral health knowledge for families who received preventive oral health services in a medical setting. Methods: Using a prospective cohort study, children 0-3 years of age received an oral health screening, risk assessment, caregiver education, and a fluoride varnish treatment in an ambulatory pediatric medical clinic. A 16-item oral health knowledge and socio-demographic questionnaire was delivered to the caregiver of child. This questionnaire included knowledge, behavior and opinion items on risk factors for dental diseases, care of child's …

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 …

Prediction Of In-Vivo Antimuscarinic Activity (Ama) By In-Vitro Receptor Binding Assessment And Pk/Pd Modeling For Prototypical Drugs, Taghrid Y. Obied

Theses and Dissertations

Purpose: To establish a tool, termed as antimuscarinic activity (AMA), to predict the incidence of antimuscarinic adverse events (AMAEs).Methods: A literature review, focused on drugs having off-target interaction with muscarinic receptors, was performed. Prototypical drugs olanzapine, diphenhydramine, paroxetine were selected for the analysis. Scopolamine and darifenacin were included as positive and negative controls, respectively. Physiochemical properties, pharmacokinetic data, and clinical incidence of AMAEs for the selected drugs were collected from reported literature. Extrapolation of literature data was carried-out to obtain exposure data. To determine the drugs muscarinic affinity (Ki values), experiments were performed using 3H-QNB and membrane suspensions of M1, …

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 …

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. …

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 …

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 …

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 …

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 …

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 …

The Relapsing Fever Spirochete, Borrelia Hermsii, And Complement Regulatory Proteins, Kelley M. Hovis

Theses and Dissertations

Borrelia hermsii, the primary etiological agent of tick-borne relapsing fever in North America, binds the complement regulatory protein factor H (FH) as a means of evading opsonophagocytosis and the alternative pathway of complement. The sequence of the gene encoding the FH-binding protein has been determined. The protein is unique to B. hermsii and has been designated FhbA. Analyses of B. hermsii isolates revealed that FhbA is expressed by 24 of the 25 isolates tested. fhbA was demonstrated to be a single genetic locus through pulsed-field gel electrophoresis, restriction digest, and hybridization analyses, and all isolates possessing fhbA carry it on …

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 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 …

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 …

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, …

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 …

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 …

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 …

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), …

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.

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 …