Medicine and Health Sciences Commons^™

Exploring The Heteromeric Interface Of The 5-Ht2a-Mglu2 Receptor Complex, Mohamed Aarif Abdul Kareem

Theses and Dissertations

Schizophrenia is a serious mental disorder characteristic of several neurotransmitters including dopamine, serotonin, and glutamate being in imbalance. Early therapies focused solely on dopamine antagonism and second-generation antipsychotics focused on the dopamine and serotonin systems and their respective G protein coupled receptor (GPCR) proteins. Although debate for dimerization of certain classes of GPCR exist, the establishment of an mGlu2-5-HT_2A heterocomplex, which is implicated in schizophrenia is of interest. Previous studies have used a mutation-based approach to identify transmembrane domain 4 (TM4) as the domain responsible in mGlu2 for mediating heteromerization before narrowing down the individual amino acids responsible for …

A Comparison In Pediatric Dental Website Design From A Guardian And Pediatric Dentists’ Perspective., David M. Voth

Theses and Dissertations

Purpose: This project aims to determine which aspects of pediatric dental practice websites are preferable to the guardians of pediatric dental patients and which of these aspects are currently available to guardians on the websites of pediatric dental practices across the United States. The comparison will reveal if practice websites are meeting the needs of the guardians of pediatric dental patients. Our hope is to provide meaningful guidance to pediatric dentists designing new practice websites and to provide the guardians of pediatric dental patients with an appealing online experience during their use of the aforementioned websites. Methods: A survey with …

Investigating The Role Of Oncogene C-Terminal Binding Protein (Ctbp) In Pancreatic Ductal Adenocarcinoma, Kranthi Kumar Chougoni

Theses and Dissertations

The transcriptional coregulator CtBP2 has been implicated as an oncogene in colon, prostate, breast and ovarian cancers. Previously, we reported overexpression of CtBP2 in human PDAC specimens. However, its exact role in PDAC is still unclear. In the current study, we attempt to delineate the oncogenic role CtBP2 in PDAC growth and metastasis. Using an orthotopic syngeneic pancreatic tumor mouse model (CKP), we found that deletion of Ctbp2 decreases PDAC tumor growth, proliferation, metastasis, EMT and significantly prolongs survival. Further, we identified significant downregulation of Erbb3 mRNA levels upon deletion of Ctbp2 in CKP PDAC cells As ErbB3 signaling was …

Strategies And Devices For Improving Respiratory Drug Delivery To Infants And Children With Cystic Fibrosis, Karl Bass

Theses and Dissertations

Cystic Fibrosis (CF) is a degenerative disease, which causes thickening of the airway surface liquid and reduced mucociliary clearance, which provides an ideal habitat for bacterial infections. Early treatment of CF in children can prevent chronic infection, improve quality of life, and increase life expectancy. The most predominant bacteria found in CF-diseased lungs is Pseudomonas aeruginosa (Pa), which can be treated with inhaled tobramycin. Excipient enhanced growth (EEG) powder formulations are well suited for administering tobramycin to children, as the EEG approach provides minimal upper airway loss and targeted drug delivery. This method uses an initially small aerosol for high …

A Theoretically-Based Mixed Methods Approach To Examining Mental Health Disorders And Help-Seeking Behaviors Among University-Enrolled African American Men, Kofoworola D.A. Williams

Theses and Dissertations

Recent studies show that African American men in college are disproportionately experiencing high levels of psychological distress, increasing their risk of developing mental health symptoms associated with depression and anxiety. Despite being at higher risk for developing mental health symptoms, university-enrolled, African American men are not seeking help even when experiencing high levels of stress and anxiety, impacting their academic performance. The evidence base describing mental health symptom prevalence and evidence-based prevention strategies among university-enrolled, African American men is limited. To that end, this dissertation work utilized a concurrent, mixed methods approach, theoretically-based in the Social Ecological Model (SEM), to …

Examining Body Mass Index And Sepsis Mortality At One Year After Sepsis, Jamie D. Robinson

Theses and Dissertations

Introduction: Sepsis is a serious and life-threatening syndrome affecting 1.7 million Americans annually and resulting in approximately 270,000 deaths. An “obesity paradox” where obese individuals have lower sepsis mortality than their non-obese counterparts has been described. The problem is that the longevity of the effect is unknown, and few studies have examined the obesity paradox after 1-2 months post-diagnosis.

Methods: This retrospective cohort study examined clinical, demographic, and biomarker variables thought to affect sepsis mortality at three-time points: 30 days, 180 days, and at one year post-sepsis diagnosis in order to shed light on specific factors that might define …

Development Of A Torque-Based Device For The Quantification Of Arm Rigidity In Patients With Parkinson’S Disease, Georgina O. Miller

Theses and Dissertations

Parkinsonian rigidity is caused by the inability of the muscles to relax and extend properly, due to reduced dopamine levels and often begins on one side of the body before spreading contralaterally. The current standard for determining joint rigidity in a clinical setting is a test completed by the clinician based on the feel of the relaxed wrist and elbow joints as they are passively flexed and extended and a series of ordinal rating scales, the Movement Disorder Society’s – Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), Hoehn and Yahr Scale (H&Y), and Parkinson’s Disease Questionnaire-39 (PDQ-39). These methods are used …

Development Of Dexamethsone Sodium Phosphate Loaded Nanoparticles For Treating Corneal Allograft Rejection, Vineet R. Kulkarni

Theses and Dissertations

Corneas are the most commonly transplanted tissue worldwide, with approximately 80,000 transplantations performed in the United States in 2018 alone. Corneal transplantation is used to restore the vision due to opaque corneas in various diseases such as fungal keratitis, keratoconus, Fuchs’s dystrophy, corneal ulceration, traumatic injury, abrasions or scarring, inflammation, and infection. Corneal transplant surgery could involve replacing the entire cornea (penetrating keratoplasty) or selective replacement of the corneal layers (e.g. Descemet’s membrane endothelial keratoplasty and deep anterior lamellar keratoplasty). Immunologic graft rejection is one of the main causes of graft failure in these corneal transplantations. The 2-year rejection rate …

A Qualitative Analysis Of Caregiver Goals For Urban Children With And Without Asthma, Megan M. Carlson

Theses and Dissertations

Pediatric asthma is a major public health concern that disproportionately affects children of color and youth living in low-income, urban areas. The implications for public health, child health, and family functioning necessitates our understanding and addressing experiences by families who are facing barriers within their socio-demographic context in addition to the stressors associated with managing pediatric asthma. The current study applied qualitative methods to interviews with caregivers of children with and without asthma in an effort to more deeply connect with caregivers’ experiences and yield richer information about the intersection of identities as Black caregivers living in an urban setting …

Characterization Of The Gonococcal Calprotectin Zn-Acquisition System, Tdfh, And The Efficacy Of Metal Starvation For Treating Gonococcal Disease, Michael T. Kammerman

Theses and Dissertations

Abstract

Characterization of the Gonococcal Calprotectin Zn-Acquisition System, TdfH, and the Efficacy of Metal Starvation for Treating Gonococcal Disease.

By Michael T. Kammerman, B.S.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University

Virginia Commonwealth University, 2020

Major Director: Cynthia Nau Cornelissen, Ph.D.

Professor, Department of Microbiology and Immunology

Neisseria gonorrhoeae, the bacterial agent that is responsible for the human disease gonorrhea, has had a steady increase in the number of infections per year. In 2018 the WHO estimated over 87 million infections occurred world-wide, and the CDC …

The Quantified Elf, Umico Niwa

Theses and Dissertations

The Quantified Elf is an ongoing collection of scientific, medical, archaeological articles and excerpts from my personal journal. It is a way by which I explore the various ways Western notions of personhood subsume human life into constructs of sexuality and gender, overlooking the various other modes of unbridled existence: plant, microbial. fungal, animal, celestial bodies. The speculative medical papers propose novel forms of body modification to combat gender dysphoria.

The Impact Of Aging And Mechanical Injury On Alveolar Epithelial And Macrophage Responses In Acute Lung Injury And Inflammation, Michael S. Valentine

Theses and Dissertations

Patients with severe lung pathologies, such as Acute Respiratory Distress Syndrome (ARDS), often require mechanical ventilation as a clinical intervention; however, this procedure frequently exacerbates the original pulmonary issue and produces an exaggerated inflammatory response that potentially leads to sepsis, multisystem organ failure, and mortality. This acute lung injury (ALI) condition has been termed Ventilator-Induced Lung Injury (VILI). Alveolar overdistension, cyclic atelectasis, and biotrauma are the primary injury mechanisms in VILI that lead to the loss of alveolar barrier integrity and pulmonary inflammation. Stress and strains during mechanical ventilation are believed to initiate alveolar epithelial mechanotransduction signaling mechanisms that contribute …

Epigenetic Regulation Of Drug Metabolizing Enzymes In Normal Aging, Mohamad M. Kronfol

Theses and Dissertations

Geriatric populations are at a higher risk for adverse drug reactions (ADRs). This may be partly due to changes in drug metabolism in old age, but the underlying mechanisms are poorly understood. Prior research in humans and mice has shown age-associated changes to the expression of several genes involved in drug metabolism. Furthermore, studies of human blood showed that epigenetic regulation of genes encoding drug metabolizing enzymes change with age. However, it is unknown if genes in the liver are similarly affected. Therefore, we hypothesize that genes encoding drug metabolizing enzymes may show differential epigenetic regulation in the liver with …

3-D Homology Modeling Of Organic Anion Transporters (Oats): Defining The Biochemical Basis For Oat-Substrate Interactions, Christopher Jay

Theses and Dissertations

A goal in the drug development process, as indicated by the FDA, is to evaluate a drug’s ADME profile, as potential drug interactions could exist, leading to adverse drug reactions or loss of efficacy. Transport proteins, specifically organic anion transporters (OATs) are involved in the absorption, distribution, and elimination of small, negatively charged compounds. Although there is an exhaustive list of structurally diverse organic anions which interact with OATs, interactions at a molecular level are still shrouded in mystery particularly due to the lack of a solved crystal structure. Therefore, in silico homology models (hOAT1, 2, 3) were generated using …

Signaling Mechanism Responsible For 5-Ht2a Receptor Tolerance To Psychedelic Induced Head-Twitch Behavior In Mice, Audrey R. Mcmurtrie

Theses and Dissertations

In recent years, there has been a growing interest in psychedelic compounds stemming from their promising use as therapeutic agents and research tools that can be used to treat and study several neuropsychiatric disorders. Psychedelics have proven useful in a broad range of these diseases - they serve as models for psychosis in schizophrenia but have also had promising results in treating major depressive disorder, anxiety, and other common disorders. Decreased stigmatization surrounding psychedelics has further increased their use in research and clinical settings. In light of these trends and the promising nature of their use, a thorough understanding of …

Effects Of Gestational Ozone Exposure On Privileged Placental And Brain Barrier Integrity, Alexander I. Hamm

Theses and Dissertations

Ambient outdoor ozone, a common of component of photochemical smog and urban air pollution, is linked to various neurological and vascular pathologies. Its immediate reaction with lung surfactant after inhalation results in complete reactivity of the gas, with no active ozone passing into circulation. This indicates the presence of secondary and tertiary mediators in ozone-related systemic pathologies after pulmonary insult. In vasculature, ozone exposure is associated with an acute hypertensive phenotype apparent at least 24 hours after dose, such as experienced on a hot summer afternoon in a large metropolitan area like Los Angeles or Mexico City. However, the effects …

An Identification Of Tgf-B'S Role In Ischemic Cholangiopathy, Courtney Chmielewski

Theses and Dissertations

Organ transplants are a necessary intervention for many diseases that result in end stage organ failure. The donation pool cannot match the demands of the transplant list, so expanding the pool to include donation after cardiac death (DCD) is desired. However, there are increased odds of graft failure and ischemic cholangiopathy leading to inferior outcomes when DCD livers are used. Ischemic cholangiopathy consists of multiple diffuse strictures and fibrosis of the bile ducts leading to a loss of epithelialization and fibrosis. The cellular mechanism is proposed to be epithelial-to-mesenchymal transition (EMT). TGF-�� is seen as a key initiator of EMT, …

Modeling Gardnerella Host-Pathogen Interaction: Characterization Of Vaginolysin And The Opacity Phenotype, Erin M. Garcia

Theses and Dissertations

Bacterial vaginosis (BV) describes a dysbiotic state of the vaginal mucosa, during which the dominance by beneficial lactobacilli species is lost, the vaginal pH increases, and the flora comprising the vaginal microbiome becomes more diverse. Bacterial taxa associated with this dysbiotic state interact to form a dense polymicrobial biofilm on the surface of the vaginal epithelium. This shift in the vaginal microflora is clinically important, even when symptoms are not noted, as women with BV are at increased risk for acquisition of other sexually transmitted infections, including HIV, and are more than two times as likely to experience preterm birth. …

New Persistent And Chronic Opioid Use In Cancer Survivors After Curative Intent Radiation, Elena V. Fernández

Theses and Dissertations

Background: Emerging evidence suggests that as more patients are surviving cancer, new persistent opioid use (no prior exposure to opioids before cancer therapy but requiring opioid prescriptions after curative intent treatment; NPOU) is of greater concern. In patients receiving curative intent radiation (definitive radiation therapy and as treatment for cure; CIR), the extent to which patients develop NPOU or continue opioid use (COU) following CIR is not known. Neither are factors associated with NPOU or COU, opioid doses, or time to discontinuation (TTD) of opioids in 5CS known. Objectives: Describe longitudinal trends opioid use in cancer survivors who received CIR, …

Estimating Response Status In Sequential Multiple Assignment (Smar)-Like Trials, Keighly Bradbrook

Theses and Dissertations

Sequential, multiple assignment, randomized trials (SMARTs) allow investigators to develop and compare experimental treatment regimens in which individuals are successively randomized to different treatments based on some set of predetermined rules. The rules used to make decisions on when and how to switch treatments are based on a chosen set of tailoring variables. Although not always true, intermediate response is commonly used as the primary tailoring variable as it is often predictive of future treatment success. As such, successful implementation depends on identifying patients who respond to treatment, though in some situations such mechanisms may not exist. Further, patient-level covariates …

Data Science Methods For Standardization, Safety, And Quality Assurance In Radiation Oncology, Khajamoinuddin Syed

Theses and Dissertations

Radiation oncology is the field of medicine that deals with treating cancer patients through ionizing radiation. The clinical modality or technique used to treat the cancer patients in the radiation oncology domain is referred to as radiation therapy. Radiation therapy aims to deliver precisely measured dose irradiation to a defined tumor volume (target) with as minimal damage as possible to surrounding healthy tissue (organs-at-risk), resulting in eradication of the tumor, high quality of life, and prolongation of survival. A typical radiotherapy process requires the use of different clinical systems at various stages of the workflow. The data generated in these …

Model-Based In-Vitro Pk/Pd Profiling Of Novel Synthetic Allosteric Effectors Of Hemoglobin (Aeh) As Potential Sickle Cell Disease (Scd) Therapeutics, Xiaomeng Xu

Theses and Dissertations

Introduction: Allosteric effectors of hemoglobin (AEH) represent a class of synthetic aromatic aldehydes that transiently form covalent interactions (Schiff-base) with hemoglobin (Hb) to form Hb-AEH adduct, preventing the HbS polymerization and sickling of red blood cells (RBC). The overall objective of this research was to aid in the optimization of novel AEH by understanding their target-site disposition of AEH in relevant biological matrices, e.g., HbA solution, whole blood (WB) and human liver cytosol (HLC), a surrogate of aldehyde dehydrogenase (ALDH)-mediated oxidative metabolism.

Methods: A “universal” HPLC-UV/Vis assay method was developed for the quantitation of HbA-AEH adduct for chemically …

Recovery From Visual Dysfunction Following Mild Traumatic Brain Injury Is Associated With Adaptive Reorganization Of Retinal Inputs To Lateral Geniculate Nucleus In The Mouse Model Utilizing Central Fluid Percussion Injury., Vishal C. Patel

Theses and Dissertations

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality nationwide. Prevalence of mild TBI (mTBI) vastly outnumbers more severe forms however the associated morbidity has only recently gained public attention. Visual dysfunction is a significant component of mTBI associated morbidity with recovery of function linked with improvement in global outcomes. Examination of sensory and motor pathways in other brain injury paradigms support that recovery is largely dependent on adaptive plasticity of remaining connections. Current examinations of visual function recovery following mTBI is limited to identifying evidence for recovery and objective evidence for adaptive plasticity is limited. Therefore, …

Integration Of Multi-Omic Platforms To Understand The Regulation Of Genes In Human Disease, Eva Lancaster

Theses and Dissertations

Epigenetic mechanisms have been hypothesized to modify gene expression (GE) in response to both genetic variation and environmental exposures, ultimately contributing to the development of complex traits. Epigenome-wide association studies (EWAS) aim to test the theory that marks of DNA methylation (DNAm) have downstream consequences that result in the development of complex diseases. Although these methods have been successful in identifying DNAm patterns in complex traits, specific molecular mechanisms involved in the etiology of complex diseases remain unidentified. This knowledge gap does not originate from a lack of DNAm-trait associations, but rather stems from study design issues that affect the …

The Impact Of The Fda Warning On Post-Tonsillectomy Opioid Prescribing In Publicly And Privately Insured Children, Dianna J. Soelberg

Theses and Dissertations

Due to reports of significant adverse events, the U.S. FDA placed a Boxed Warning on the opioid codeine in February 2013 – contraindicating its use in pediatric patients undergoing tonsillectomy and/or adenoidectomy. Studies conducted in privately insured children showed a reduction in codeine prescribing and a slight increase in alterative opioid prescribing following the FDA warning, yet the extent to which the FDA warning impacted prescribing in publicly insured children is unknown. Using a quasi-experimental interrupted time series design, this study evaluated codeine and alternative opioid prescribing before and after the FDA warning in both publicly and privately insured children …

The Impact Of Occupational Therapy Acute Care Services On Readmission Rates For Patients In Medicare’S Hospital Readmission Reduction Program, Jessica M. Edelstein

Theses and Dissertations

The United States (US) health care system is faced with the daunting challenge to make healthcare payments commensurate with quality of care provided. To assess quality, metrics for reimbursement have been established by Medicare. One such quality metric is hospital readmissions (readmissions). Readmissions are associated with poor patient outcomes and costly. Associated poor patient outcomes include higher risk for mortality, deconditioning, nutritional issues and cognitive impairments. As a result, readmissions cost Medicare $26 billion annually. Current strategies for reducing readmissions in the US are fragmented and hospital-specific. While specific strategies may vary, hospitals that have low readmissions rates tend to …

The Effect Of The Senolytic Abt-263 On Androgen Deprivation-Induced Senescent Prostate Tumor Cells, So Min Lee

Theses and Dissertations

Prostate cancer (PCa) is one of the leading causes of cancer-related deaths in men. Although standard treatments such as androgen deprivation therapies (ADT) and antiandrogens have increased survival for many patients, most men placed on these therapies will develop castration-resistant disease (CRPC). Previous studies have shown that these treatments have limited cytotoxicity and instead promote cell growth arrest. Our current work demonstrates that prostate tumor cells grown in the absence of androgens by using charcoal-stripped serum undergo senescence-mediated or senescent-like growth arrest, based on the cellular expression of senescence-associated-beta-galactosidase (SA-β-Gal). Our studies further suggest that this senescence is transient and …

Black Women And Body Image: Implications Of The Racialized Beauty Aesthetic, Rachel L. Boutte

Theses and Dissertations

Black women have the highest prevalence of overweight and obesity relative to any other demographic group in the United States, however current weight management interventions appear least effective for them. Although several hypotheses have been proposed to explain these outcomes, few studies have collected data to evaluate how well they fit the lived experiences of Black women. In particular, the potential roles of body image and body dissatisfaction in the development and maintenance of overweight and obesity in Black women are not well understood. Extant literature largely reports that Black women are inoculated from body dissatisfaction due to cultural factors, …

Exosomes As Systemic Mediators Of Nanotube Induced Neurotoxicity, Christopher G. Canal

Theses and Dissertations

Extra-pulmonary effects of nanoparticle inhalation have been well documented; however, mechanisms for conveying peripheral bioactivity remain elusive. Recent studies point to indirect molecular mediators shed into the circulation. Protein and lipid alternatives to cytokines or chemokines have been proposed, yet the diversity among responses suggests a broader assemblage of factors. Recently we have proposed proteolytic fragment peptides as an additional source of bioactivity, which interestingly were significantly associated with exosomal proteins after enrichment analysis. Here we tested whether modeled exposure to multi-walled carbon nanotubes (MWCNT) could alter the composition and bioactivity of circulating exosomes. Male C57BL/6 mice were exposed by …

Investigation Of Molecular Mechanisms Of Liver Preservation Injury: A Complication Preceding Organ Transplantation, Ria C. Fyffe-Freil

Theses and Dissertations

Of the over 108,000 American awaiting a life-saving organ transplant today, over 12,000 (11%) of those need a new liver (OPTN, 2020). Last year, only 35% of patients on the waiting list for an organ were transplanted. Improving the quality of marginal organs by preventing or reversing preservation injury could vastly increase the number of transplants performed. Washout of circulating blood during liver procurement with cold University of Wisconsin solution flushes out any endogenous pro-survival signaling molecules. We investigated lysophospholipid (LPL) surface receptors (G-protein coupled receptors for lysophosphatidic acid (LPA) and sphingosine- 1-phosphate (S1P)) and their role in protecting hepatocytes …