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Effects Of Protein Timing And Energy Balance On Body Composition In Collegiate Athletes, Ashley Licata Jan 2019

Effects Of Protein Timing And Energy Balance On Body Composition In Collegiate Athletes, Ashley Licata

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The current literature indicates that energy balance and protein consumption influence body composition. However, the effects of protein intake, timed protein supplementation, and energy balance on body composition have not yet been fully investigated in collegiate athletes. The purpose of this research was to assess collegiate athletes using hourly food and exercise data to examine how protein timing and energy balance relate to body composition. Aims 1 and 2 focus on collegiate female soccer athletes and further our understanding of the potential roles that protein amount and frequency and hourly energy balance play in optimizing fat mass and fat-free mass. …

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External Root Resorption In The Orthodontic Patients, Frank Earl Litchfield Jan 2019

External Root Resorption In The Orthodontic Patients, Frank Earl Litchfield

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External Apical Root Resorption (EARR) is a side effect of orthodontic treatment that results in root shortening in about one-third of orthodontic patients. Great variability among patients exists in their susceptibility to this multifactorial condition, and both treatment and patient specific factors contribute to EARR. Root resorption values were found to be higher in Hispanics compared to Asians and Caucasians (1). However, the prevalence of EARR is not well documented in all populations. Since African Americans represent the largest minority group in the United States, establishing the prevalence and risk factors for EARR within this ethnicity is important. Objective: To …

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Smile Outcome Comparison Of Orthodontic Cases Treated With Different Extraction Patterns, Gregory Long Jan 2019

Smile Outcome Comparison Of Orthodontic Cases Treated With Different Extraction Patterns, Gregory Long

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Extraction of premolar teeth for orthodontic purposes is a common treatment approach. The effects of premolar extraction on the occlusion and the face have been studied extensively in the past. To date, however, the effects of premolar extractions on the smile have not been comprehensively quantified in the literature. The purpose of this study was to compare the smile outcome of patients treated with premolar extractions. Methods: This retrospective case-control study established 4 groups of 33 patients each for comparison. Three groups of patients with the same malocclusion were treated with different premolar extraction patterns. The remaining group of patients …

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Structural Studies Of Some Proteins Responsible For Bacterial Pathogenesis, Kartik Manne Jan 2019

Structural Studies Of Some Proteins Responsible For Bacterial Pathogenesis, Kartik Manne

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A wide range of infections is attributed to the pathogenesis of Gram-positive bacteria. The emergence of multi-drug-resistant Gram-positive pathogens has been a significant health concern and present serious therapeutic challenges globally. Some of the common Gram-positive bacterial species like Streptococcus pneumonia, Group B Streptococcus, and Staphylococcus aureus are infectious by employing several virulence factors for initial adhesion, colonization, biofilm initiation and dispersion, complement evasion, nutrient acquisition, and infection. The structural insights into these virulence factors are essential for understanding their mode of action, and also for developing a new class of antibiotics; a significant interest of many researchers. Pneumococcal adhesive …

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The Benefit Of Resilience: Examining The Roles Of Family Resilience And Parental Education In Child Anxiety, Bria Kathryn Morgan Jan 2019

The Benefit Of Resilience: Examining The Roles Of Family Resilience And Parental Education In Child Anxiety, Bria Kathryn Morgan

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Extensive literature addresses the associations between parental education and children’s mental health outcomes; however, the role of parental education and family resilience in child anxiety is unclear. The purpose of this study is to obtain a greater understanding of the role of parental education in child anxiety. Additionally, the study aims to investigate the role and potential varying effects of family resilience. Building upon Bowen’s Family Systems Theory and Walsh’s Systems Theory of Family Resilience, I hypothesize that parental education will be negatively associated with child anxiety and that family resilience will be negatively associated with child anxiety. I also …

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The Real-Time Extractiion Of Neural Spikes For Brain-Machine Interface Application Using Deep Learning Algorithm, Patel Sahaj Anilbhai Jan 2019

The Real-Time Extractiion Of Neural Spikes For Brain-Machine Interface Application Using Deep Learning Algorithm, Patel Sahaj Anilbhai

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The detection of neural spikes in real-time and accurately has become the center of interest for the researchers in the field of brain-machine/computer interface (BMI/BCI). The primary challenge in the Brain-Machine interface is to translate raw neuronal response signals into the control of electrical actuators. Only accurate and rapid classification of neural response can help efficiently and conveniently to disable peoples, particularly those suffering from spinal cord injury, stocks, etc., Recording from neurons and analyzing them with many different methods are not new. However, the primary challenge here is the real-time recording and classifying the spikes with higher accuracy. In …

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Examining Teachers' Perceptions And Practices Of Family Engagement With Families Of Emergent Bilinguals In Pre-Kindergarten And Kindergarten Classrooms: A Mixed Methods And Multiple Case Study, Julie I. Paul Jan 2019

Examining Teachers' Perceptions And Practices Of Family Engagement With Families Of Emergent Bilinguals In Pre-Kindergarten And Kindergarten Classrooms: A Mixed Methods And Multiple Case Study, Julie I. Paul

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This study addressed pre-K and kindergarten teachers’ perceptions and practices of family engagement with families of students who are Dual Language Learners/Emergent Bilinguals. The study employed an explanatory sequential mixed methods design (Quan --> QUAL) (Creswell & Plano-Clark, 2018). To address the purpose of the study, the overarching mixed methods question was: How do pre-K and kindergarten teachers engage families of all their students and families of students who are emergent bilinguals? Mixing of the strands occurred after the quantitative data was collected. Quantitative results helped develop the semi-structured interview protocol for the qualitative phase of the study. Qualitative results …

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Bayesian Hierarchical Negative Binomial And Zero-Inflated Negative Binomial Models For High-Dimensional Analyses With Applications To Human Microbiome Count Data, Amanda H. Pendegraft Jan 2019

Bayesian Hierarchical Negative Binomial And Zero-Inflated Negative Binomial Models For High-Dimensional Analyses With Applications To Human Microbiome Count Data, Amanda H. Pendegraft

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The human microbiome was first described as an “ecological community of commensal, symbiotic, and pathogenic microorganisms that literally share our bodyspace”. These microorganisms, also known as microbes and bacteria, are known for participation in human health. For example, microbes extract energy from foods that are otherwise indigestible, synthesize vitamins and amino acids necessary for important bodily functions, and protect hosts against disease-carrying pathogens. Therefore, the pursuit of human microbiome research is important for understanding the influence of microorganisms throughout human systems. Human microbiome research is founded on advances in next-generation sequencing technology. Namely, the identification of microbes that constitute the …

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The Reductive Stress Reducto-Mir: Emerging Insight Into Microrna-671, Justin Michael Quiles Jan 2019

The Reductive Stress Reducto-Mir: Emerging Insight Into Microrna-671, Justin Michael Quiles

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Excessive accumulation of reactive oxygen and nitrogen species (ROS/RNS) promotes cardiac pathophysiology. Although extreme oxidative burden is cytotoxic, ROS/RNS are continually generated within multiple domains of cardiac myocytes, and these species play fundamental roles in signal transduction through reversible thiol oxidation. Nuclear factor, erythroid 2 Like 2 (Nfe2l2/NRF2) is activated by ROS/RNS and binds cis regulatory antioxidant response elements (AREs) to induce the expression of a host of thiol oxidoreductases which regulate signaling events at the post-translational, transcriptional and epigenetic levels. Although oxidative stress has been linked to cardiac disease, adaptive processes in the heart require reduction-oxidation (redox) reactions as …

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Determination Of The Role Of Smu_833 In The Fitness And Virulence Of Cariogenic Streptococcus Mutans, Katherine Lynn Rainey Jan 2019

Determination Of The Role Of Smu_833 In The Fitness And Virulence Of Cariogenic Streptococcus Mutans, Katherine Lynn Rainey

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Dental caries, commonly known as tooth decay, is the most common infectious disease worldwide. The main etiological agent of dental caries is Streptococcus mutans which can readily form a biofilm on the surface of teeth and produce acids through the metabolism of dietary sugars, which is largely responsible for the demineralization and subsequent destruction of tooth enamel. In addition, S. mutans synthesizes extracellular glucosyltransferases (Gtfs) capable of breaking apart dietary sucrose and polymerizing the glucose subunits into the sticky glucan matrix of the biofilm, imperative for the formation of robust, three-dimensional biofilms. Currently used caries therapies are not species-specific and …

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The Role Of Suppressor Of Cytokine Signaling 3 In Neuroinflammatory Disease, Zhaoqi Yan Jan 2019

The Role Of Suppressor Of Cytokine Signaling 3 In Neuroinflammatory Disease, Zhaoqi Yan

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The Janus Kinase/Signal Transducers and Activators of Transcription (JAK/STAT) pathway plays a critical role in cytokine-mediated responses in both innate and adaptive immunity, and dysregulation of the JAK/STAT pathway is linked to many inflammatory disorders. Multiple Sclerosis (MS) is an inflammatory demyelinating disease that affects the central nervous system, and both innate and adaptive immunity are involved in disease progression. STAT3 signaling is critically involved in MS pathology and is negatively regulated by Suppressor Of Cytokine Signaling 3 (SOCS3). Both increased STAT3 activation and reduced SOCS3 expression are observed in immune cells from patients with MS. Although the role of …

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The Effect Of Right Ventricular Insertion Cooling On Wavebreak Initiation Following Defibrillation Shocks, Han Yu Jan 2019

The Effect Of Right Ventricular Insertion Cooling On Wavebreak Initiation Following Defibrillation Shocks, Han Yu

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Although strong defibrillation shocks can save patients from life-threating tachyarrhythmias, the function of the heart may be compromised. We found in an earlier study that the right ventricular insertion (RVI) is responsible for most of the initial propagation failure (wavebreak) that drives the transition from ventricular tachycardia (VT) to ventricular fibrillation (VF). To determine whether suppression of wavebreak at the RVI region can decrease VF re-occurrence after defibrillation, thereby decreasing the defibrillation shock strength threshold (DFT), a cooling method was developed to impede waves from propagating between the right ventricle (RV) and the left ventricle (LV) through the RVI. The …

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A Deep Learning Framework For Medical Image Segmentation, Zheng Zhang Jan 2019

A Deep Learning Framework For Medical Image Segmentation, Zheng Zhang

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Deep Learning (DL) has rapidly become a methodology of choice for analyzing medical images and increasingly attracts researcher’s attention in the medical research community. The brain is one of the most important organs in the human body. Within the context of human brain disease, research and care, accurately detecting, evaluating and segmenting human brain abnormalities play an important role in brain disease diagnosis, prognosis, and treatment planning. A significant challenge in developing good brain abnormalities segmentation methods is the high variation of brain abnormalities such as differences in shape, size, location, appearance, and regularity. Deep Learning approach ad-dresses this challenge …

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Self-Tracking Practices: The Roles Of Social Contexts And Chronic Conditions, Aowen Zhu Jan 2019

Self-Tracking Practices: The Roles Of Social Contexts And Chronic Conditions, Aowen Zhu

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The rapid development of mobile health (mHealth) technologies is propelled by the culture of disease prevention and management. Smartphone applications and wearable devices provide valuable personal data for self enhancement. In addition to health promotion, people with chronic conditions are using apps and devices to monitor symptoms and behaviors. There is great potential for self-tracking practices to reduce health care cost and improve population health. However, the emphasis on personal responsibility of individuals’ health may hinder the long-term effectiveness of self-tracking practices. The purpose of the study is to examine the associations between social contexts and self-tracking practices, chronic health …

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Exposure Assessment Of Ultrafine Particles And Hazardous Chemicals In Electronic Cigarettes, Oluwabunmi Magret Dada Jan 2019

Exposure Assessment Of Ultrafine Particles And Hazardous Chemicals In Electronic Cigarettes, Oluwabunmi Magret Dada

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The widespread use of electronic cigarettes (e-cig) among youths and adolescents is a growing public health problem due to exposures to harmful byproducts formed during heating. These byproducts include particulate matter, benzene, and toluene. However, the mechanisms and variables governing their formation including the chemical content of e-cig liquid (e-liquid) are not fully understood. This study aimed to assess exposures to particulate matter, benzene, and toluene in e-cig vapors (e-vapors) and their coupling to e-liquid chemical content. A novel nuclear magnetic resonance spectroscopy method was developed to characterize e-liquids (propylene glycol, glycerol, and nicotine) and the functional content of flavorings. …

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Kidney Resident Macrophages Utilize Developmental Programming During Healing From Acute Kidney Injury, Jeremie Matthew Peabody Lever Jan 2019

Kidney Resident Macrophages Utilize Developmental Programming During Healing From Acute Kidney Injury, Jeremie Matthew Peabody Lever

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Acute kidney injury (AKI) can be a devastating condition, affecting up to sixty percent of critically ill patients in the United States. Despite the fact that AKI is associated with an increased risk of chronic kidney disease (CKD) and mortality, there are no targeted therapies available to treat it. Kidney resident macrophages (KRM) are likely necessary for healing and resolution of animal models of AKI. However, there remains a gap in knowledge regarding how KRM effect this function. The purpose of my thesis was to elucidate lineage relationships and functionally relevant adaptations of KRM and monocyte-derived mononuclear phagocytes (infiltrative MP) …

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Characterizing The Hiv-1 Envelope N-Glycan Shield, Audra Ann Hargett Jan 2019

Characterizing The Hiv-1 Envelope N-Glycan Shield, Audra Ann Hargett

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In 2017, there was an estimated 1.8 million new HIV-1 infections worldwide. Development of an effective HIV-1 vaccine would begin to quell this global pandemic. HIV-1 envelope (Env) glycoprotein is the main vaccine candidate target due to the immune systems ability to generate broadly neutralizing antibodies (bnAbs) against Env. Approximately 90 N-glycans form a glycan shield that is the primary interface between the virus and host immune system. Key glycan motifs within the glycan shield are targets for bnAbs and are necessary for HIV-1 infectivity. Herein, we explore how naturally occurring mutations alter the glycan shield and HIV-1 Env function. …

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Investigating The Rho-Kinase (Rock) Signaling Pathway As A Therapeutic Target In Alzheimer’S Disease, Benjamin Wade Henderson Jan 2019

Investigating The Rho-Kinase (Rock) Signaling Pathway As A Therapeutic Target In Alzheimer’S Disease, Benjamin Wade Henderson

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Current estimates project that there are approximately 5.4 million Americans affected by Alzheimer’s disease (AD). While this number is expected to dramatically increase in the years to come, there is currently no disease modifying therapeutic to prevent or slow AD progression. Cognitive decline is a clinical hallmark of AD, while accumulation of amyloid-β (Aβ) is a pathological hallmark. Work in the field has demonstrated that mitigating Aβ levels may serve as a rational therapeutic avenue to slow progression of the disease. Pharmacologic inhibition of the Rho-associated protein kinases (ROCK1 and ROCK2) is proposed to curb Aβ levels, and mechanisms that …

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The Influence Of O-Glcnacylation On Dna 5-Hydroxymethylation In The Epileptic Hippocampus, Richard Gilbert Sánchez Jan 2019

The Influence Of O-Glcnacylation On Dna 5-Hydroxymethylation In The Epileptic Hippocampus, Richard Gilbert Sánchez

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Epilepsy is a neurological disorder that affects roughly 3 million Americans and 65 million individuals worldwide. Although there are several known causes of epilepsy, little is understood about the development of epilepsy or epileptogenesis. What has been observed through multiple studies of epilepsy is an alteration of the proteomic profile, along with a distinct change in post-translational modifications (PTM). Studies have focused on phosphorylation and a variety of kinases that are upregulated during epilepsy with little clinical translation. This dissertation investigates O-GlcNAcylation, a PTM that is highly intertwined with the cellular metabolism, and its epigenetic effects on gene expression via …

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Postpartum Body Composition And Breast Milk Hormones, Camille Schneider Jan 2019

Postpartum Body Composition And Breast Milk Hormones, Camille Schneider

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The prevalence of both adult and child obesity continues to rise. Children born to mothers with obesity have a greater risk for future obesity and chronic disease. There is an increasing body of literature suggesting that pregnancy and infancy are critical periods influencing the child’s risk for obesity. However, little is known about whether consumption of breast milk from an obese mother might influence the child’s metabolic programming and growth. The purpose of this dissertation was to examine the association of maternal adiposity with insulin and leptin in breast milk and, in turn, whether breast milk insulin, leptin, and glucose …

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Targeting The Nad Salvage Pathway For The Treatment Of The Parasitic Disease Schistosomiasis, Michael David Schultz Jan 2019

Targeting The Nad Salvage Pathway For The Treatment Of The Parasitic Disease Schistosomiasis, Michael David Schultz

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Schistosomiasis, also known as bilharzia, is the third most common parasitic infection worldwide and a major source of morbidity and mortality in developing countries. Caused by trematodes in the genus Schistosoma, this parasitic disease has no vaccine therapy and resources for drug development are scarce. Despite an unknown mechanism of action, praziquantal has become the primary source of treatment due to its efficacy against all species of Schistosoma. However, with increased drug resistance in endemic areas and low activity against immature parasites, relying on this single drug is unsustainable and risky. Hence, there is a growing need for new, safe …

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Optimizing Toc Removal For Dbp Reduction In Drinking Water While Overcoming Source Water Variations, April Nabors Jan 2019

Optimizing Toc Removal For Dbp Reduction In Drinking Water While Overcoming Source Water Variations, April Nabors

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Department of Civil, Construction, and Environmental Engineering University of Alabama at Birmingham ABSTRACT This dissertation used a holistic approach to research ways to optimize disinfection by-product (DBP) reduction during each sector of the conventional drinking water treatment process, regardless of the source water type or quality, in an overall effort to meet the USEPA Stage 2 Disinfection/Disinfection By-Products Rule (D/DBPR). DBPs are formed from the reaction between naturally occurring total organic carbon (TOC) in the water and disinfectants used during the treatment process. For this dissertation, effective treatment was measured by the amount of TOC that was removed through the …

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A Deep Learning Approach For Identifying Key Biomarkers In Medical Imaging Applications, David Odaibo Jan 2019

A Deep Learning Approach For Identifying Key Biomarkers In Medical Imaging Applications, David Odaibo

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Although Deep Leaning has achieved great success in many domains in recent years, research into its applicability and effectiveness in medical applications has been limited for various reasons. Some of these barriers are related to the historic impression that neural networks are black boxes, especially when applied to medical diagnosis and offer no in terpretation into prediction. In this dissertation, I demonstrated that deep learning can be an effective utility in medical diagnosis and biomarker detection. In particular, I have developed deep learning models that can identify biomarkers in brain hemorrhage, brain tumor, pneumonia, diabetic retinopathy and Parkinsons disease, with …

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Overcoming Obesity-Induced Immunotherapeutic Impairment, Shannon Boi Jan 2018

Overcoming Obesity-Induced Immunotherapeutic Impairment, Shannon Boi

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Obesity affects ~40% of United States adults and is linked to the development of multiple health-related complications. Obesity is a major risk factor for developing renal cell carcinoma (RCC), the most common type of renal cancer. Metastatic RCC has poor five-year survivals, therefore, new, efficacious therapeutics are needed. One avenue is immunomodulation to generate tumor-specific, systemic anti-tumor responses that are long-lasting against local, metastatic, and recurrent tumors. Despite encouraging results, immunotherapeutic treatment of RCC is underwhelming. Cytokine therapies are largely toxic, while newly FDA-approved ‘checkpoint blockade’ (CB) antibodies have responses <50%. Here, we present a strategy employing a T cell priming therapy (AdTR/CpG) upstream of CB administration. Combinatorial use resulted in improved anti-tumoral immune responses, significantly reduced tumor burdens, and extended overall survival in pre-clinical RCC. Importantly, this approach was more efficacious than either single agent(s). Pre-clinical therapy development is often accomplished using lean, healthy animals–thus, to improve translatability we examined immune responses in the context of obesity as a major patient comorbidity. Subsequently, we investigated AdTR/CpG/CB in diet-induced obese (DIO) mice. Tumor/treatment-naïve DIO mice exhibited obesity-associated features; i.e., increased leptin/insulin and serum cytokines. These effects were not dependent on high-fat diet administration as mice resistant to weight gain had minimal alterations in these factors, and were similar to mice maintained on standard chow. As previously identified, 80% of DIO mice bearing renal tumors failed to respond to AdTR/CpG. AdTR/CpG/CB-treatment dramatically improved response rates against DIO tumors, however, decreased obese responder percentages were observed in both combinatorial therapies and was independent of high fat diet administration alone. Impaired response rates were not model or immunotherapy-specific as similar reductions in tumor clearance were seen in models of melanoma and sarcoma. Furthermore, responses were not due to initial T cell priming or unequal precursor CD8+ T cell frequencies. Detrimental changes in the tumor microenvironment underscored failure in obese mice and revealed therapeutic success was defined by a T cell-myeloid cell-inversion profile, supported by immunogenetic and flow cytometric analyses. Thus, we demonstrate a novel combinatorial approach for improving checkpoint-based outcomes, and identify the ability of host obesity to impede therapy-induced anti-tumor immunity.

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St6gal-I Sialyltransferase Regulates The Activity Of Surface Receptors To Control Cell Signaling In Cancer And Immune Cells, Andrew Holdbrooks Jan 2018

St6gal-I Sialyltransferase Regulates The Activity Of Surface Receptors To Control Cell Signaling In Cancer And Immune Cells, Andrew Holdbrooks

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Among the four classes of biological macromolecules, glycans are essential for proper cellular functioning. However, our knowledge of the contribution of these sugars, including the glycosyltransferases that add them, to cell signaling is limited. This dissertation focuses on the role of the ST6Gal-I sialyltransferase in modulating receptor-mediated signal transduction in cancer and inflammation. ST6Gal-I is a Golgi enzyme that conjugates α2-6-linked sialic acids to N-linked glycans on select glycoproteins. Through its sialylation of surface receptors, ST6Gal-I activity can significantly modify their function. The first section of this dissertation concentrates on the ST6Gal-I-mediated regulation of the signaling pathway of TNFR1, which …

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The Association Between Perceived Discrimination And Depressive Symptomatology Among The Children Of Caribbean Immigrants, Fabrice Stanley Julien Jan 2018

The Association Between Perceived Discrimination And Depressive Symptomatology Among The Children Of Caribbean Immigrants, Fabrice Stanley Julien

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Caribbean societies often speak to the in-between, acknowledging the race categories that exist between and within the “black” or “white” designations. But outside of this context and particularly in American society, individuals from the Caribbean pursue identity through a more categorical approach. What influences these decisions is often the occupied status of families. These occupied statuses offer different advantages and disadvantages, which can inform perceptions/experiences of daily stressors. Using a modified version of Pearlin’s stress process model, this research assesses how ethnic self-identification colors perceptions of stressors such as discrimination, and how this in turn influences one’s depressive symptomatology. Using …

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Novel Mediators Of The Blood Pressure Response To Acute Psychosocial Stress In Health And Disease, Brandon Fox Jan 2018

Novel Mediators Of The Blood Pressure Response To Acute Psychosocial Stress In Health And Disease, Brandon Fox

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Psychosocial stress occurs in response to threatening or uncertainty-provoking stimuli and triggers a complex physiological reaction that facilitates survival and adaptation. In the cardiovascular system, acute psychosocial stress elicits a rapid increase in blood pressure, and importantly, cumulative exposure to psychosocial stress is a risk factor for cardiovascular disease. The present studies examined the impact of psychosocial stress on the cardiovascular system in both health and disease. Circulating endothelin-1 (ET-1) levels are induced by psychosocial stress. We hypothesized that endothelium-derived ET-1 contributes to the pressor response to stress via activation of the endothelin A (ETA) receptor. Vascular endothelium-specific ET-1 knockout …

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Centrifugal Microfluidics For Label-Free Isolation Of Leukocytes Subpopulations From Whole Blood, Yuxi Sun Jan 2018

Centrifugal Microfluidics For Label-Free Isolation Of Leukocytes Subpopulations From Whole Blood, Yuxi Sun

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Leukocytes carry critical information regarding the immediate immune and inflammation status of the patients. Analysis of leukocytes requires isolation from blood since the leukocytes only consist <1% of all blood cells. Commonly used isolation processes exploit physical or biochemical differences between different cell types to enable separations. Current isolation methods inevitably subject cells to physical or biochemical stress that can activate leukocytes and change their natural state. Thus, information contained within isolated leukocytes is a combination of the natural state of the cell and an artifact of the isolation process. Microfluidics which takes advantage of scaling effects within microscale structures can ensure rapid and gentle alternatives to conventional isolation methods and is ideal for sorting, and analysis of cells and particles. The precise control of flow/particles and scaling effects of microfluidics have been applied for blood cells sorting and isolation. However, the limited processing capability and throughput as well as complex fabrication and operations have hampered widespread adoption of these approaches for replacement of conventional methods. My goal was to develop a simple yet powerful microfluidic tool that enables rapid separation of leukocytes while ensuring sufficient throughput, and minimizing isolation process induced activation without the need any sample pre-processing. This project is divided into two specific aims: i) to miniaturize the conventional density gradient centrifugation using centrifugal microfluidics for PBMC isolation and evaluate separation efficiency and activation status of isolated cells in comparison to conventional techniques; ii) develop new approach for PBMC sorting using microfluidic phase partitioning to enable separation of cells based on differences in cell surface energy. For specific aim 1, PBMCs were isolated based on differences in densities using microfluidic density gradient centrifugation. We show that PBMCs can be isolated from 100µl whole blood within 5 minutes. Evaluation of leukocyte activation via profiling of expression of surface integrins and chemokine receptors shows that our microfluidic approach significantly reduced PBMC activation in comparison to conventional isolation approaches. In specific aim 2, we sought to isolate cells based on differenced in surface energy using two-phase partitioning of dextran (DEX) and polyethylene glycol (PEG). Proof of concept demonstrations was accomplished using with polystyrene and silicon dioxide microbeads which represent a mixture of white blood cells and red blood cells. The DEX and PEG mixtures were introduced into a circular channel and phase separated under centrifugal force into unique DEX and PEG phases. The bead mixture was isolated via differences in their affinity to the two phases.

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Heart Failure In A Contemporary Biracial Cohort, Matthew Mefford Jan 2018

Heart Failure In A Contemporary Biracial Cohort, Matthew Mefford

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Heart failure (HF) is the inability of the heart to meet the perfusion needs of the body. HF is a leading contributor to the burden of cardiovascular disease (CVD) and remains a public health concern. Hypertension is a major modifiable risk factor for the prevention and management of HF. Hypertension develops earlier, is less controlled, and has a stronger association with some CVD and renal outcomes among blacks versus whites. These disparities may extend to HF. In addition, adults with HF often have complex treatment regimens due to multimorbidity, making medication adherence an issue. The goal of this dissertation was …

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Religion/Spirituality And Mental Health/ Well-Being Among Women Living With Hiv, Haley Medved Kendrick Jan 2018

Religion/Spirituality And Mental Health/ Well-Being Among Women Living With Hiv, Haley Medved Kendrick

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Depression among people living with HIV (PLWH) is associated with social factors such as employment, poor adherence to HIV medication and treatment, and HIV disease progression. However, estimates of prevalence rates of depression among PLWH vary widely, from 1% to 48%. Women living with HIV (WLWH) often report spirituality as an important factor in coping with stressors associated with HIV infection. Spirituality has been found to be associated with social involvement, effective coping, decreased stress, psychological adjustment, and positive mental health outcomes among PLWH. The current study aims to longitudinally examine trends of spirituality and mental health/well-being in the lives …

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