Digital Commons Network^™

The Role Of Cyclin-Dependent Kinase 8 In Vascular Disease, Desiree Leach

Theses and Dissertations

In response to injury, mature vascular smooth muscle cells (SMCs) undergo dedifferentiation, also known as phenotype modulation or switch. This process is characterized by a downregulation or loss of expression of contractile genes and concomitant with an increase in cell proliferation, migration, and extracellular matrix production, thereby leading to vascular lesion formation. However, the underlying molecular mechanism is not fully understood. The objective of my study was to determine whether cyclin-dependent kinase 8 (CDK8), a transcription-regulating kinase, plays a mediator role in vascular SMC dedifferentiation and lesion formation. Our results from immunochemical staining and Western blot revealed that CDK8 expression …

The Effect Of Paid Sick Leave On Physician Office-Based Visits, Korvin Vicente

Theses and Dissertations

This paper uses a balanced sample of workers from cross-sections of the National Health Interview Survey to estimate the causal effects of paid sick leave on the medical care seeking behavior of individuals, as measured by physician office-based visits.

Perceptual Analysis Of Children's Adaptation To An Electropalatography Sensor, Kasey Marie Duffield

Theses and Dissertations

The purpose of this study is to observe childrens adaptation to an electropalatographic (EPG) sensor. Sound recordings of six children between the ages of 7;0 and 9;11 sampled at 30-minute intervals over a two-hour period of wearing an EPG sensor were perceptually evaluated to quantify the children's adaptation over time. Twenty native speakers of American English evaluated the pronunciation of a series of words with embedded stops and fricatives produced with and without an EPG sensor in place. When collapsed over speaker and stimulus type, listener ratings decreased significantly after inserting the EPG sensor. Ratings then increased significantly after the …

Perceptual Analysis Of Children's Adaptation To An Electropalatography Sensor, Kasey Marie Duffield

Theses and Dissertations

The purpose of this study is to observe childrens adaptation to an electropalatographic (EPG) sensor. Sound recordings of six children between the ages of 7;0 and 9;11 sampled at 30-minute intervals over a two-hour period of wearing an EPG sensor were perceptually evaluated to quantify the children's adaptation over time. Twenty native speakers of American English evaluated the pronunciation of a series of words with embedded stops and fricatives produced with and without an EPG sensor in place. When collapsed over speaker and stimulus type, listener ratings decreased significantly after inserting the EPG sensor. Ratings then increased significantly after the …

Quantifying Lingua-Palatal Contact Patterns Of Fricative Productions By Non-Native Students Enrolled In A University German Language Course: An Electropalatography Study, Kate Erin Lester

Theses and Dissertations

Electropalatography (EPG) is a computer-based tracking system designed to provide real-time visual biofeedback of articulatory contacts occurring during speech production. Historically, EPG technology has proven functional within the treatment and assessment of speech disorders however, application of EPG technology to assist in second language learning has remained limited. The present thesis is part of a larger study examining the effectiveness of using EPG as an advanced instructional tool for assisting second language (L2) learners of German. Fricative productions ([ç], [x], /s/, and /∫/) within real words were gathered from 12 native English speakers enrolled in a second semester university level …

Influence Of Health Beliefs On Diabetes Self-Care In Saudi Adults, Moudi Albargawi

Theses and Dissertations

The prevalence of Diabetes Mellitus Type 2 (DMT2) has increased among the adult population in Saudi Arabia. Many Saudi adults with DMT2 fail to follow the recommended daily self-care activities, increasing their risk for diabetes-related complications. Findings in the literature show that people’s health beliefs influence their self-care behaviors. However, limited studies were found to examine the association between the health beliefs of Saudi adults with DMT2 and their diabetes self-care. Therefore, the aim of this dissertation study was to examine the relationship between the health beliefs of adults in Saudi Arabia with DMT2 and their reported adherence to their …

Combinatorial Efficacy Of Antimicrobial Peptides And Silver Ions, Christina Lynne Chrom

Theses and Dissertations

Antimicrobial peptides are produced by multicellular organisms as a defense against competing pathogenic microbes. The mechanism of action for positively charged antimicrobial peptides is widely believed to occur when the positively charged peptide interacts with the negatively charged outer lipid membrane followed by the insertion of the peptide into the membrane. This insertion into the outer or cytoplasmic membranes leads to disruption of membrane integrity. Alternatively, silver based antimicrobials, which have been well known for centuries, are thought to act by inhibiting the proton motive force, the respiratory electron transport chain, and by affecting membrane permeability resulting in cell death. …

Role Of The Pediatric Dental Provider In Human Papillomavirus (Hpv) Education, Meredith L. Dugoni

Theses and Dissertations

Purpose: This study investigates knowledge about HPV and examines if pediatric dental providers should include HPV education for guardians of patients 10-18 years.

Methods: Legal guardians of 10-18 year-old patients of the Virginia Commonwealth University Pediatric Dental Clinic were enrolled in this prospective cohort study. Participants completed a baseline survey, were provided HPV education, completed an initial follow-up survey, and then completed a 6-month follow-up survey.

Results: A total of 54 participants completed the baseline and initial follow-up surveys and 17 completed the 6-month follow-up survey. The average number of correct responses was 3.4 of 6 knowledge questions, which significantly …

Investigating The Relationship Between Emotional Intelligence And Cultural Intelligence To Attitudes Towards Team-Based Learning In Undergraduate Pre-Health Profession Students, Kevin A. Harris

Theses and Dissertations

Improving patient outcomes has long been the rationale supporting calls to reform health care delivery systems and health profession education programs (Greiner, 2002; Institutes of Medicine, 2001, 2004; O’Neil & Pew Health Professions Commission, 1998). In 2003, the Institute of Medicine shared its vision statement for health professions education, asserting that “[a]ll health professionals should be educated to deliver patient-centered care as members of an interdisciplinary team, emphasizing evidence-based practice, quality improvement approaches and informatics” (Knebel & Greiner, 2003, p. 3).

Despite the importance placed on teamwork in health sciences education, little attention has been devoted to understanding underlying factors …

Work-Related Musculoskeletal Disorders Among Dentists And Orthodontists, Natalie R. La Rochelle

Theses and Dissertations

WORK-RELATED MUSCULOSKELETAL DISORDERS AMONG DENTISTS AND ORTHODONTISTS

A thesis submitted in partial fulfillment of the requirements for the degree of

Master of Science in Dentistry at Virginia Commonwealth University.

by

Natalie R. La Rochelle

Thesis Director: Dr. Eser Tüfekçi, D.D.S., M.S., Ph.D., M.S.H.A.

Professor, Department of Orthodontics

Virginia Commonwealth University

Richmond, Virginia

May 2017

The practice of dentistry is physically demanding due to static and dynamic postures sustained daily throughout careers. Previous literature suggests that work-related musculoskeletal disorders (WMSD) are not solely the result of work habits, but also due to the individual, his or her physical makeup, genetics, and …

Comparison Of Intraoral And Extraoral Scanners On The Accuracy Of Digital Model Articulation, Jason L. Porter

Theses and Dissertations

Introduction: Orthodontists increasingly rely on digital models in clinical practice. The ability of modern scanners to articulate digital models must be scientifically evaluated. Methods:Twenty five digital articulated models were produced from four digital scanners in five experimental groups. The resulting inter-arch measurements were compared to the gold standard. An acceptable range of 0.5mm more or less than the gold standard was used for evaluation. Results: iTero® and iTero® Element yielded all acceptable inter-arch measurements. The 3M™ True Definition and Ortho Insight 3D® with Regisil® bite registration produced four of six acceptable inter-arch measurements. The Ortho Insight 3D® with Coprwax ™ …

Nitrosative Stress Sensing In Porphyromonas Gingivalis: Structure And Function Of The Heme Binding Transcriptional Regulator Hcpr, Benjamin R. Belvin

Theses and Dissertations

Porphyromonas gingivalis, a Gram negative anaerobe implicated in the progression of periodontal disease, is capable of surviving and causing infection despite high levels of reactive nitrogen species found in the oral cavity due to its efficient nitrosative stress response. HcpR is an important sensor-regulator that plays a vital step in the initiation of the nitrosative stress response in many Gram negative anaerobic bacteria. We employ a combination of X-ray crystallography, SAXS, resonance Raman spectroscopy, UV-Vis spectroscopy, and molecular biology techniques to better understand this key regulator. Knockout of the hcpR gene in W83 P. gingivalis results in the inability of …

Provider Appearance: A Survey Of Guardian And Patient Preference, Joshua Westphal

Theses and Dissertations

Purpose: To understand guardian and child preferences for the appearance of their pediatric dentist. This was a cross-sectional descriptive study using survey methodology with patients and parents that attended the VCU Pediatric Dental clinic.

Methods: A total sample of 100 guardians and 97 pediatric patient participants completed the computer-based questionnaire. Four subjects were asked to pose for photographs wearing various combinations of attire (professional, casual, white coat, scrubs).

Results: Among guardians, 56% reported preferring a provider in scrubs, with white coat the second most preferred attire (39%) for their children. For pediatric patients, scrubs were still most often selected, …

A Comparison Of Treatment Planning Modalities For The Pediatric Dental Patient, Martha M. Holland

Theses and Dissertations

Purpose: To assess the treatment modalities of pediatric dentists for restoring Class II lesions in primary molars.

Methods: A survey of eight cases was emailed to AAPD members, who were asked to choose a stainless steel crown (SSC) or composite resin. Treatment choice was associated with provider type, years in practice, behavior management, lesion detection, and patient age.

Results: Clinically detectable caries restored under general anesthesia were treated more often with a SSC. Faculty and residents chose a SSC at a greater rate. Providers with 10 or more years experience chose a SSC more often.

Conclusions: The scope of treatment …

The Prevalence, Predictive Factors, And Classification Of Intrapulpal Cracks In Maxillary Molars Requiring Endodontic Treatment, Husain Karashi

Theses and Dissertations

Diagnosis and treatment of teeth with longitudinal fractures is challenging. Cracks are usually not visible radiographically; they require a thorough evaluation to aid in diagnosis. Patients may be asymptomatic, demanding the dentist rely on clinical findings to make a diagnosis. Early diagnosis of the presence and extent of a crack is essential for the successful management of a cracked tooth. There is limited information in the literature regarding the prevalence or predictive factors of cracks extending into the pulp chamber of teeth. The purpose of this study was to determine the prevalence of intrapulpal cracks in maxillary molars and to …

Amixicile Inhibits Anaerobic Bacteria Within An Oral Microbiome Derived From Patients With Chronic Periodontitis, Kane Ramsey

Theses and Dissertations

Periodontitis is a chronic inflammatory disease caused by pathogenic bacteria residing in a complex biofilm within a susceptible host. Amixicile is a non-toxic, readily bioavailable novel antimicrobial that targets strict anaerobes through inhibition of the activity of Pyruvate Ferredoxin Oxidoreductase (PFOR), a major enzyme mediating oxidative decarboxylation of pyruvate. Our study aimed to evaluate the efficacy of amixicile, when compared to metronidazole, in inhibiting the growth of bacteria present in a microbiome harvested from patients with chronic periodontitis.

Plaque samples were harvested from patients with severe chronic periodontitis and cultured under anaerobic conditions. The microbiomes were grown in the presence …

A Comparison Of Moderate Oral Sedation Drug Regimens For Pediatric Dental Treatment: A Pilot Study, Ojas A. Parikh

Theses and Dissertations

Purpose: Compare moderate oral sedation of pediatric patients using Hydroxyzine and Meperidine with either Diazepam or Midazolam in management of pediatric dental patients.

Methods: Randomized, double-blind, crossover pilot study of patients 3 to 7 years of age requiring two sedation visits. Frankl and Houpt behavior scores recorded at injection time, initiation of treatment and 100% oxygen at end of treatment. Postoperative phone call surveys conducted within eight hours and within 24 hours of discharge. Wilcoxon Signed-Rank tests, Fisher’s Exact Chi-squared test and 0.10 significance level.

Results: 25 subjects completed 35 sedations. Eight participants completed both treatments and demonstrated significantly higher …

Prevalence And Clinical Characteristics Of Teeth Extracted With A Diagnosis Of Cracked Tooth: A Retrospective Study, Riley B. Sturgill

Theses and Dissertations

The body of knowledge that exists regarding cracked teeth is limited. The purpose of this study was to determine the prevalence of cracks among extracted teeth. This retrospective longitudinal cohort study included patients of the Virginia Commonwealth University School of Dentistry that underwent extraction procedures over a 6 year period. The sample consisted of 20,408 patients and 40,870 teeth. Statistical analysis software was used to identify diagnoses of a crack, fracture, or split tooth prior to extraction of the tooth by analyzing the Electronic Health Record (EHR) (axiUm™, Version 6.03.03.1035, Exan Corporation, Vancouver, BC, Canada). There were 3,228 teeth …

A Systems Biology Approach For Predicting Essential Genes And Deciphering Their Dynamics Under Stress In Streptococcus Sanguinis, Fadi El-Rami

Theses and Dissertations

Infectious diseases are the top leading cause of death worldwide. Identifying essential genes, genes indispensable for survival, has been proven indispensable in defining new therapeutic targets against pathogens, major elements of the minimal set genome to be harnessed in synthetic biology, and determinants of evolutionary relationships of phylogenetically distant species. Thus, essentiality studies promise valuable revenues that can decipher much of biological complexities.

Taking advantage of the available microbial sequences and the essentiality studies conducted in various microbial models, we proposed a framework for the prediction of essential genes based on our experimentally verified knowledge of the pathways involved in …

Individual Differences In Markers Of Cholinergic Signaling Correlating To Fear And Extinction Learning, Grace C. Jones

Theses and Dissertations

Posttraumatic stress disorder (PTSD) results when individuals are exposed to a life threatening event, assault, serious injury, or other traumatic incident. Individuals with PTSD are impaired in their ability to extinguish fear memories, resulting in intrusive symptoms that impair their ability to live otherwise healthy lives. It remains unclear why some individuals exposed to traumatic events develop PTSD while others do not. Acetylcholine has been shown to play a critical role in fear learning, but its role in fear extinction is not well understood. This study utilized a rat model of fear learning and extinction to determine if individual differences …

Muscarinic Acetylcholine Receptor M1’S Impact On Fear Extinction Learning, Joshua R. Mcelroy

Theses and Dissertations

Post-Traumatic Stress Disorder (PTSD) is a mental health disorder that can occur following a traumatic event like combat, assault, or disaster. Individuals with PTSD are unable to extinguish fear memories which can become chronic and disabling. However, it remains unclear why some individuals exposed to a traumatic event develop PTSD while others are resilient. Acetylcholine plays a critical role in fear learning, but its role in fear extinction is less well understood. In this investigation, we used a rat model of fear extinction to determine if individual differences in extinction learning are correlated with markers of cholinergic signaling. Cholinergic markers …

Developing And Implementing A Quality Assurance Strategy For Electroconvulsive Therapy, Jessa Hollingsworth

Theses and Dissertations

The literature provides scant guidance in effective quality assurance strategies concerning the use of electroconvulsive therapy (ECT) for the treatment of psychiatric conditions. Numerous guidelines are published that provide guidance in the delivery of care, however, little has been done to determine how a program or facility might ensure compliance to best practice for safety, tolerability, and efficacy in performing ECT. The objective of this project was to create a quality assurance strategy specific to ECT. Determining standards for quality care and clarifying facility policy were key outcomes in establishing an effective quality assurance strategy. An audit tool was developed …

Silver Diamine Fluoride And Oral Health-Related Quality Of Life, Nazafarin Javdan

Theses and Dissertations

Purpose: The purpose of this study was to study the association between Silver Diamine Fluoride (SDF) and Oral Health-Related Quality of Life as assessed by “The Early Childhood Oral Health Impact Scale” questionnaire. Methods: Parents of healthy children (ASA I and II) ages 1-5 with early childhood caries with reversible pulpitis who had application of SDF filled out a questionnaire at baseline and again after one month. The questionnaire was designed to evaluate the child’s behavior, physical abilities, pain, temperament, and how well the child gets along with others. Results: Wilcoxon Signed Rank Test was used to …

Contribution Of A Class Ii Ribonucleotide Reductase To The Manganese Dependence Of Streptococcus Sanguinis, John L. Smith

Theses and Dissertations

Manganese-deficient Streptococcus sanguinis mutants exhibit a dramatic decrease in virulence for infective endocarditis and in aerobic growth in manganese-limited media. Loss of activity of a manganese-dependent, oxygen-dependent ribonucleotide reductase (RNR) could explain the decrease in virulence. When the genes encoding this RNR are deleted, there is no growth of the mutant in aerobic broth culture or in an animal model. Testing the contribution of the aerobic RNR to the phenotype of a manganese transporter mutant, a heterologous class II RNR from Lactobacillus leichmannii called NrdJ that requires B₁₂ rather than manganese as a cofactor was previously introduced into an …

The Role Of Human Msc Derived Exosomes In The Treatment Of Periodontal Diseases, Sonia S. Talegaonkar

Theses and Dissertations

Periodontal disease affects 47% of Americans over 30. Characterized by microbial dysbiosis and unregulated inflammation, severe periodontitis causes degradation of bone and soft tissue around teeth. Current treatments have limited regenerative outcomes and frequent reinfection by harmful bacteria. Human mesenchymal stem cells (hMSCs) have been shown to promote wound healing and tissue regeneration. Many therapeutic benefits of hMSCs are due to their secretome products, like exosomes. Our long-term goal is to develop periodontal therapies with hMSC exosomes. The objectives of this study were to determine the effect of hMSC-derived exosomes on cellular activity of hMSCs and investigate whether hMSC exosome …

Evaluation Of Volumetric Change Of Periapical Lesions After Apicoectomy As A Measure Of Postsurgical Healing Utilizing Cone Beam Computed Tomography, Eshwar Arasu

Theses and Dissertations

The aim of this study was to evaluate whether volumetric changes in persistent periapical lesions can be detected in follow-ups six months to five years after apicoectomy using cone-beam computed tomography. Patients with a previous treatment history of apicoectomy and for whom a pre-surgical CBCT scan was taken between November 2010 and December 2015 were invited to participate in the study. A post-surgical CBCT image of the treated tooth was obtained at the recall visit. Volumetric and linear measurements of periapical lesions on initial and postoperative CBCT images were performed using DiThreshGUI software and two calibrated examiners—a board-certified endodontist and …

An Investigation Of Surface Characteristics Of Enamel Treated With Infiltrative Resin: A Scanning Electron Microscopy Study, Danielle E. Easterly

Theses and Dissertations

AN INVESTIGATION OF SURFACE CHARACTERISTICS OF ENAMEL TREATED WITH INFILTRATIVE RESIN: A SCANNING ELECTRON MICROSCOPY STUDY

Danielle E. Easterly, Doctorate of Dental Surgery.

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University.

Virginia Commonwealth University. 2017.

Director: Dr. Eser Tüfekçi

D.D.S., M.S., Ph.D., M.S.H.A.

Objective: To evaluate the microstructural changes of a resin infiltrant (ICON®, DMG America LLC, Englewood, NJ) after six months of simulated toothbrushing.

Materials and Methods: Ten extracted third molars (n=10) were collected. Artificial white spot lesions were created and resin applied. Environmental SEM …

A Comparative Study Of Intraradicular Enterococcus Faecalis Biofilm Removal With Three Root Canal Treatment Systems: A Scanning Electron Microscopy Evaluation, Cyrous Ardalan

Theses and Dissertations

The objective of this study was to evaluate the biofilm removal efficacy of three root canal treatment systems: ProUltra® PiezoFlow™, traditional needle irrigation, and the GentleWave® system in an ex-vivo benchtop study. Twenty-four extracted maxillary and mandibular molars were selected. Teeth were all instrumented to a master apical file size #25 with 4% taper. Teeth were then randomly divided into four experimental groups and two control groups. The root canals were inoculated with a culture of Enterococcus faecalis and incubated for five weeks to form a biofilm. Each group was then treated with one of the different root canal treatment …

Assessing The Relationship Between Periodontal Disease And Subsequent Inflammatory Responses And Headache Disorders, Bryn E. Davis

Theses and Dissertations

Headaches are the sixth leading cause of disability worldwide, and the third leading cause of disability amongst those aged 50 and older. Several headache disorders, including migraines, have been associated with nitric oxide production. It is widely accepted that the pain associated with headache disorders is due to the ability of nitric oxide to function as a vasodilator. While nitric oxide is a known vasodilator and has been linked to headache disorder, it is also produced in response to bacterial infections. Periodontal disease is the result of long term bacterial infections occurring in the gum line and nitric oxide is …

Synergism Of Quercetin And Sodium Butyrate For Controlling Growth Of Glioblastoma, Matthew Alan Taylor

Theses and Dissertations

Glioblastoma multiforme (GBM), or simply glioblastoma, is the most common and aggressive primary brain tumor, with a prevalence of approximately 20,000 new cases per year in the United States and a 3-year survival rate of just 2%. Quercetin (QCT) is a dietary flavonoid that can be found in common foods such as red kidney beans, cilantro, and onions. Despite little evidence showing any benefits through dietary intake of QCT, various studies show its promising anti-cancer results in vitro. In glioblastoma, QCT is able to cause significant amounts of apoptosis through a variety of mechanisms. These include activation of caspase-9 and …