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Vasopressor Titration In Medical Intensive Care Patients With Septic Shock: A Descriptive Study, Daniel Arellano

Dissertations and Theses (Open Access)

Background: Vasopressor therapy in patients with septic shock can lead to harmful effects.

Objective: To describe vasopressor titration in patients with septic shock.

Methods: Single-center descriptive study of 60 intensive care unit (ICU) patients to calculate rates for events of failure to titrate, incorrect titration, and correct titration in 15- minute intervals for the duration of vasopressor therapy. Total hospital and ICU days, mortality rate, vasopressor dose and time, and the impact of hydrocortisone on vasopressor use were examined.

Results: During the total vasopressor infusion time of 2598 hours, 5395 failure-to-titrate events were noted. There were 316 incorrect titrations and …

An Exploration Of Psychosexual Functioning And Factors Affecting The Prophylactic Decision-Making Process In Women Of Childbearing Age With A Brca 1/Brca2 Mutation, Alexis Hayes

Dissertations and Theses (Open Access)

Background: A breast cancer type 1 and type 2 susceptibility protein (BRCA1/BRCA2) gene mutation carries an 85%- 90% lifetime risk of developing breast cancer and a 27%-65% chance of developing ovarian cancer. There is minimal evidence regarding how psychosexual functioning, the psychological well-being in regards to body image and sexuality, affects the decision to have prophylactic treatment in women of childbearing age (18 - 49) with a BRCA gene mutation. Diagnosis of a BRCA gene mutation presents a dilemma where life-changing medical decisions must be made to prevent breast and ovarian cancer. Throughout decision-making and following surgical prophylactic interventions, such …

Mhealth Acceptance And Usage Among South Asian Adults In The U.S., Padmavathy Ramaswamy

Dissertations and Theses (Open Access)

Background: Modifiable lifestyle factors such as physical inactivity and unhealthy diet contribute to the increased risk of cardiovascular diseases (CVD) and diabetes (DM) in South Asians (SAs) (Volgman et al., 2018). Interventions using mobile health (mHealth) have demonstrated feasibility and potential efficacy for ethnic minorities (Bender et al., 2018), and have the potential to be of preventive and therapeutic value in reducing the burden of CVD and DM in SAs living in the US. However, there is a gap in knowledge regarding the usage and acceptance of mHealth among SAs.

Purpose: The objectives were to examine the overall …

Predictors Of Short-Term Residential Treatment Completion Preceded By Detoxification For Opioid Use Disorder, Christopher Gideon

Dissertations and Theses (Open Access)

Background and Significance: Deaths related to opioid overdose are increasing. Treatment for opioid use disorder (OUD) is necessary to help prevent future opioid abuse, and often involves opioid detoxification, followed by short-term residential treatment, typically lasting about 28 days. Literature regarding OUD and short-term residential treatment is limited. Predictors of short-term residential completion, including whether detoxification was performed, may help addiction professionals individualize treatments. This study’s purpose was to determine predictors of short-term residential completion treatment for OUD, and whether detoxification prior to entering residential treatment may also be a factor in residential completion.

Method: De-identified data regarding …

Understanding Diabetes Health Beliefs And Health Practices In Vietnamese Americans, Linda Sheen

Dissertations and Theses (Open Access)

Background: Diabetes related complications resulting in mortality and morbidity are higher among Vietnamese individuals living in the U.S. with diabetes. Few studies have examined the personal perceptions and cultural beliefs pertaining to disease management. An in-depth understanding of perception and cultural beliefs in regard to diabetes self-management is needed for the development of culturally appropriate interventions in this population.

Purpose: Two specific aims were explored: 1) To explore how Vietnamese individuals living in the U.S. with prediabetes and diabetes conceptualize diabetes self-management and; 2) to understand how Vietnamese individuals living in the U.S. with prediabetes and diabetes integrate …

Factors Affecting Antiretroviral Treatment Entrance, Adherence And Retention Among Hiv Patients In Nigeria And Uganda, Nnenna Ananaba

Dissertations and Theses (Open Access)

Introduction: The maximum benefits of antiretroviral therapy (ART) are achieved when HIV patients follow through the HIV Care Continuum. Understanding the factors that impact the Care Continuum are key in minimizing late ART uptake while increasing treatment retention and adherence in sub-Saharan Africa. Objectives: To explore factors that impact the various phases of the HIV Care Continuum, we review trends in median CD4 cells count and presentation with HIV advanced disease stage between 2013 and 2017. We also examined treatment retention rates and the impact of food security on ART adherence. Methods: Two datasets were reviewed. One dataset consists of …

Characterizing Risk & Burden Of Lower Cranial Neuropathy (Lcnp) As Late Effect Among Oropharyngeal Cancer Survivors, Puja Aggarwal

Dissertations and Theses (Open Access)

Background: Lower cranial neuropathy (LCNP) is a rare but potentially disabling late effect of radiotherapy (RT) and other head and neck cancer therapies. Survivors who develop late LCNP may experience profound functional impairment with deficits in swallowing, speech, and voice. The aims of this research were: 1) to quantify the cumulative incidence of late LCNP and identify clinical predictors of late LCNP; 2) to investigate the impact of late LCNP on severity of cancer treatment-related symptoms, general functional impairment (GFI), and single item scores of the most severe symptoms; and 3) to quantify the association of late LCNP with swallowing-related …

Coy Arjate Adrusted Response Adaptive Randomization Designs With Targeted Learning, Hai Zhu

Dissertations and Theses (Open Access)

Since Food and Drug Administration (FDA) issued the very first draft guidance in 2010, adaptive designs have been considered to be one of the most promising approaches to make drug development more efficient and less costly. Two approaches, covariate-adjusted response-adaptive (CARA) randomization and adaptive seamless phase II/III design (ASD) have garnered growing attention recently. However, most of the CARA designs are based on parametric models and suffered from model misspecification. The research of incorporating CARA into ASD is also limited and whether type I error rate can be controlled has not been answered. In this dissertation, a new family of …

Association Between Childhood Maltreatment And Type 2 Diabetes Mellitus: A Retrospective Cohort Study In The United States, Diep N. Poulos

Dissertations and Theses (Open Access)

This retrospective cohort study analyzed self-reported and biological data collected from MIDUS in 2004-2006 to understand the association between the types of childhood maltreatment (CM) and Type 2 Diabetes Mellitus (T2DM). The central hypothesis of this study is that childhood maltreatment is positively associated with adult onset diabetes (T2DM). CM has been associated with lifelong morbidity and an increased risk in chronic diseases such as diabetes and heart disease (Bernstein RE, 2013). In this study, CM was defined by the Childhood Trauma Questionnaire (CTQ). The CTQ has three types of abuse: physical, sexual, emotional, and two types of neglect: physical …

The Potential Impact Of Restricting The Sale Of Tobacco At Tobacco Retail Outlets Surrounding Schools Across Major Metropolitan Areas Of Texas On Tobacco Advertisements, Udoka C. Obinwa

Dissertations and Theses (Open Access)

Retail outlets that sell tobacco (ROST) are the leading channel of advertisements and promotional efforts for tobacco companies. Tobacco companies strategically target youth, young adults, racial and ethnic minorities and individuals in lower SES areas with more advertisements, which in turn influences their tobacco use behavior. Researchers have proposed instituting place-based restriction strategies as a way to control tobacco use. This dissertation examined the potential impact of i) restricting the sale of tobacco at ROST within 1000ft of schools and 2000ft of colleges and ii) restricting the sale of tobacco at ROST within 500ft of other ROST, on the number …

Studying The Properties Of Seamless Phase Ii/Phase Iii Clinical Trials Under Covariate Adaptive Randomization, Garrett Miller

Dissertations and Theses (Open Access)

Covariate adaptive randomization is an allocation procedure used in clinical trials that seeks to balance treatment groups. While this method has been shown to reduce bias due to imbalanced treatment groups, the effects of covariate adaptive randomization have not been studied under seamless Phase II/Phase III clinical trials that incorporate short-term endpoint information and treatment selection. Therefore, this analysis sought to determine whether these adaptive randomization methods can be applied to seamless Phase II/Phase III trials while preserving Type I error. In addition, this analysis sought to create R-packages that employ seamless Phase II/Phase III techniques to provide analysis tools …

Patient-Perceived Patient-Centered Medical Home Characteristics And Healthcare Utilization, Expenditure And Quality, Alissa Ratanatawan

Dissertations and Theses (Open Access)

The patient-centered medical home (PCMH) model is a care delivery model which patient treatment is coordinated through their primary care physician to ensure they receive the necessary care when and where they need it, in a manner they can understand with the aims to improve healthcare quality while keeping healthcare cost growth under control. The objective of this study was to analyze health service utilization, expenditure and quality of civilian noninstitutionalized US adult population in healthcare facilities that have 3 domains of PCMH features, which are comprehensive care, patient-centered care, and accessible care, using patient’s perspective from the 2016 Medical …

Clinical And Demographic Factors Associated With Peg-Asparaginase-Related Toxicities In Patients With Acute Lymphoblastic Leukemia, Priyadarshani Dharia

Dissertations and Theses (Open Access)

Introduction: Polyethylene glycol (PEG)-asparaginase is one of the first-line drugs in pediatric ALL treatment. Although a complete and prolonged treatment with PEGasparaginase has been instrumental in improving the survival of ALL patients, it is associated with four common toxicities: hypersensitivity, hyperbilirubinemia, pancreatitis, and venous thromboembolism (VTE). PEG-asparaginase-related toxicities may require modifications and delays in treatment, which often leads to poor treatment outcomes. Previous studies of PEG-asparaginase-related toxicities have mainly focused on individual toxicities. Further, these studies were conducted in study populations which were predominantly self-reported non-Hispanic whites. Therefore, there is a gap in the knowledge regarding the cumulative burden of …

Quantifying The Financial & Clinical Impact Of Annual Vs. Biennial Mammography Screening, Danmeng Huang

Dissertations and Theses (Open Access)

Current guidelines for screening mammography recommend different start ages and intervals for women with average cancer risk. Longer intervals between mammograms allow more time for a tumor to grow, to become symptomatic and clinically detectable, and more likely to be at advanced stage. Existing literature on the associations between mammography screening frequency and risk of more advanced breast cancer have mixed results. Studies have showed that advanced breast cancer costs more to treat, but real-world cost estimates following different mammography screening frequencies are unavailable. To fill the gaps, this dissertation aimed to quantify the clinical and financial impact following annual …

Characterizing Risk & Burden Of Lower Cranial Neuropathy (Lcnp) As Late Effect Among Oropharyngeal Cancer Survivors, Puja Aggarwal

Dissertations and Theses (Open Access)

Background: Lower cranial neuropathy (LCNP) is a rare but potentially disabling late effect of radiotherapy (RT) and other head and neck cancer therapies. Survivors who develop late LCNP may experience profound functional impairment with deficits in swallowing, speech, and voice. The aims of this research were: 1) to quantify the cumulative incidence of late LCNP and identify clinical predictors of late LCNP; 2) to investigate the impact of late LCNP on severity of cancer treatment-related symptoms, general functional impairment (GFI), and single item scores of the most severe symptoms; and 3) to quantify the association of late LCNP with swallowing-related …

Moving Beyond The Single Gene: Integrative Gene Set Analysis For Rna-Seq, Andrew Richard Aschenbrenner

Dissertations and Theses (Open Access)

RNA-seq is the next-generation sequencing technology for gene expression and while many tools have been developed to assess differential expression, most focus on gene-level statistics. Gene-level statistics implicitly ignore any dependence among genes. In order to directly incorporate correlation into testing for differential expression, genes are sorted into networks using Ingenuity Pathway Analysis (IPA) and the gene expression of each network is modeled using Generalized Estimating Equations (GEE). Since the gene network data often exhibits correlation structures containing positive and negative values, a new intermediate correlation structure is developed. This structure provides a compromise between an exchangeable (one parameter for …

Physical Activity Among Preschool-Aged Children: Considerations For Waking Activity Patterns And Health, Erin Dooley

Dissertations and Theses (Open Access)

With nearly one-quarter (23%) of U.S. preschool children (ages 3-5 years) having overweight or obesity, supporting healthy growth and development is paramount. Hispanic children have the highest prevalence within this age group (15.6%) and a large projected population growth. Energy expenditure through physical activity is one way to combat excess development of obesity and poor health outcomes. Yet there is limited evidence about the correlates associated with physical activity and health within this population. The three studies of this dissertation examined sociodemographic-, cultural-, and context-related factors related to waking activity patterns and the subsequent impact on health indicators. The overall …

Quantifying The Financial & Clinical Impact Of Annual Vs. Biennial Mammography Screening, Danmeng Huang

Dissertations and Theses (Open Access)

Current guidelines for screening mammography recommend different start ages and intervals for women with average cancer risk. Longer intervals between mammograms allow more time for a tumor to grow, to become symptomatic and clinically detectable, and more likely to be at advanced stage. Existing literature on the associations between mammography screening frequency and risk of more advanced breast cancer have mixed results. Studies have showed that advanced breast cancer costs more to treat, but real-world cost estimates following different mammography screening frequencies are unavailable. To fill the gaps, this dissertation aimed to quantify the clinical and financial impact following annual …

Epidemiological Evaluation Of The National Sickle Cell Screening Program In The Republic Of Uganda, Arielle G. Hernandez

Dissertations and Theses (Open Access)

Sickle cell anemia contributes substantially to childhood morbidity and mortality in sub-Saharan Africa, where there are scarce health resources and inadequate awareness among healthcare providers and the community. Without early diagnosis and initiation of preventive treatments, most infants will die of acute complications before their fifth birthday. Information on the mortality associated with sickle cell anemia is excluded from global statistical summaries due to the lack of accurate data, making sickle cell anemia an invisible killer of children on the African continent. Information from long-term large-scale sickle cell screening efforts is not yet available in Africa; therefore, a mixed-methods study …

The Associations Between Fat And Clinical Outcomes Among Lung Cancer Patients: Dietary Intake And Genetic Determinants, Fang Yu Lin

Dissertations and Theses (Open Access)

Higher dietary fat intake and alterations in fatty acid metabolism may affect cancer development and progression. This dissertation conducted a series of studies examining whether dietary fat intake and genetic variants in fatty acid metabolism genes have an impact on clinical outcomes among non-Hispanic whites newly diagnosed with non-small cell lung cancer (NSCLC). First, a cohort of 2,262 NSCLC patients was prospectively examined for intakes of total, saturated, monounsaturated, and polyunsaturated fat in relation to overall survival and recurrence. Dietary fat intake at diagnosis was assessed with a previously validated food frequency questionnaire and categorized by Dietary Reference Intakes. Multivariable …

External Environmental Dimensions And Financial Performance Of Major Teaching Hospitals In The U.S, Karima Lalani

Dissertations and Theses (Open Access)

Background: Teaching hospitals have a unique mission to not only deliver graduate medical education, but to also provide both inpatient and ambulatory care, and to conduct clinical and medical research; therefore, they are under constant financial pressure, and it is important to find out what types of external environmental components affect their financial performance. No recent studies have been comprehensively conducted for all major teaching hospitals in the U.S. to examine if there is an association between the external environmental dimensions based upon Resource Dependence Theory (Munificence, Uncertainty, Complexity) and the short-term financial performance, measured by days cash on hand …

Access To Antibiotics Without Prescription For Travelers And Colombian Citizens At Community Pharmacies In Bogota, Colombia, Marie Kasbaum

Dissertations and Theses (Open Access)

The misuse of antibiotics has been shown to exacerbate the global antibiotic resistance crisis, which could have major consequences on public health worldwide (Auta et al., 2018). In Bogotá, Colombia, the non-prescription sale of antibiotics still occurs in pharmacies despite national regulations requiring a prescription from a physician or health agency before dispensing antibiotics to a patient (Vacca et al., 2011). The purpose of this study was to investigate the non-prescription sale of antibiotics in community pharmacies to foreign travelers and Colombian citizens in Bogotá, Colombia. Trained Simulated Clients (SCs) gathered experimental data in pharmacies distributed throughout 20 geographic districts …

Examining Differences In Physical Activity By Socio-Demographics, Employment, And Social Support Among U.S. Adolescents, Ashleigh Marie Johnson

Dissertations and Theses (Open Access)

The overall decline in physical activity levels during adolescence supports the examination of intrapersonal-, interpersonal-, and behavior-level factors that may influence physical activity behavior among this population. The three papers within this dissertation aimed to examine associations of socio-demographics and socio-environmental factors with physical activity among U.S. adolescents. Papers 1 and 3 used data from the Family Life, Activity, Sun, Health, and Eating (FLASHE) Study. Paper 1 examined differences in adolescent physical activity by gender and race/ethnicity, and examined modification by grade and socioeconomic status (SES). Paper 3 examined the association of parent- and adolescent-reported parental social support with adolescent …

Nonlinear Functional Models On Causal Inference, Rong Jiao

Dissertations and Theses (Open Access)

Statistical analysis has experienced significant progress on association study, but it remains elusive to understand the etiology and mechanism of complex phenotypes. As a major analytical platform, association analysis may hamper the theoretic development of biomedical science and its application. Thus, many researchers suggest making the transition from association to causation. The mainstream of research in genetics and epigenetics data analysis focuses on statistical association or exploring statistical dependence between variables. Despite significant progress in dissecting the genetic architecture of complex diseases by genome-wide association studies (GWAS), the signals identified by association analysis can only explain a small proportion of …

Understanding The Relatlonships Between Survivorship Care Plans And Survivor Level Outcomes Among Breast And Colorectal Cancer Survivors, Jessica Danielle Austin

Dissertations and Theses (Open Access)

PURPOSE: Cancer survivors have complex journeys following the completion of active treatment. The Institute of Medicine and other high-profile organizations have recommended and mandated the use of a survivorship care plan (SCP) despite mixed evidence supporting the impact of SCPs on key survivor-level outcomes. The purpose of this dissertation was to understand the complex relationship linking the delivery of SCPs and to relevant survivorlevel outcomes. STUDY GROUP: This dissertation focuses on breast and colorectal cancer survivors because they comprise nearly 30% of the entire cancer survivor population in the US and are the two most prevalent cancers in men and …

The Role Of Gamma Oscillations And Cortical Inhibition In The Development Of Working Memory In Adolescence, Christopher P. Walker

Dissertations and Theses (Open Access)

Adolescence is a dynamic period of social, cognitive, and biological changes. In particular, working memory, the ability to actively encode and maintain information over a short period of time, develops early in childhood and gradually increases in capacity and stability during adolescence. The precise neurophysiological mechanism by which working memory capacity increases during adolescence is unclear. The objective of this investigation was to evaluate the role of cortical gamma-band (> 30 Hz) oscillations—which are associated with working memory in adults—for the development of working memory capacity in adolescents, and to identify the extent to which the temporal profile of gamma-aminobutyric …

A Novel Switch-Like Function Of Delta-Catenin In Dendrite Development, Ryan Baumert

Dissertations and Theses (Open Access)

The formation of neuronal networks in the brain is tightly regulated, and dependent on the morphology of dendrites, the branch-like signal-receiving structures extending from neurons. Disruptions in dendrite development, or dendritogenesis, can lead to the atypical neuronal connectivity associated with multiple neurodevelopmental diseases. My research addresses molecular processes that underlie dendritogenesis via analysis of a pair of novel interactions involving the protein delta-catenin.

In neurons, delta-catenin localizes to dendrites and synapses, where it functions in their development and maintenance. Structurally, delta-catenin possesses a central Armadillo domain and a C-terminal PDZ-binding motif. This motif associates with PDZ domain-containing proteins, and is …

Uncovering The Zeb1 Interactome To Identify Novel Regulators Of Metastatic Non-Small Cell Lung Cancer, Roxsan Manshouri

Dissertations and Theses (Open Access)

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death in the United States, due in part to the robust affinity of lung cancer cells to metastasize. Understanding the processes that contribute to metastasis provides promise for the discovery of novel therapeutic targets. Epithelial-tomesenchymal transition (EMT) is a proposed model for the initiation of metastasis. During EMT cell adhesion and polarity is reduced, allowing epithelial cancer cells to dissociate from the primary tumor and invade distant organs. The transcription factor zinc finger E-box-binding homeobox 1 (ZEB1) has been reported to uniquely correlate with NSCLC disease progression and to …

The Effect Of Traumatic Brain Injury On Tau Pathology By A Potential Seeding Mechanism, George Edwards Iii

Dissertations and Theses (Open Access)

The misfolding, aggregation and accumulation of specific proteins is the overarching concept in protein misfolding disorders (PMDs). The microtubule associated protein tau is known to form insoluble filaments known as neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau (pTau) found in a subset of PMDs called tauopathies, such as Alzheimer’s disease (AD) and chronic traumatic encephalopathy (CTE), among others. Misfolded tau engenders a structurally alternative intermediate conformation that is prone to aggregate having amyloidogenic properties. Formation of amyloids, such as tau aggregates, is proposed to follow a nucleation-polymerization model where misfolded, soluble oligomeric seeds can trigger native proteins to misfold and …

The Role Of Membrane Domains In Protein And Lipid Sorting During Endocytic Traffic, Blanca B. Diaz-Rohrer

Dissertations and Theses (Open Access)

The lipid and protein composition of the plasma membrane (PM) must be tightly controlled to maintain cellular functionality, despite constant, rapid endocytosis. Because de novo synthesis of proteins and lipids is energetically costly, the cell depends on active recycling to return endocytosed membrane components back to the PM. For most proteins, the mechanisms and pathways of their PM retention remain unknown. The work presented here shows that association with ordered membrane microdomains is fully sufficient for PM recycling and that abrogation of raft partitioning leads to their degradation in lysosomes. These findings support a model wherein ordered membrane domains mediate …