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A Larval Zebrafish (Danio Rerio) Model Of Adherent-Invasive Escherichia Coli Infections, Erika Flores, Erika Flores

Dissertations & Theses (Open Access)

Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, is a broad term for chronic intestinal disorders that severely impact patient morbidity and quality of life. The global prevalence of IBD is rising, with over one million patients affected in the US alone. Adherent-invasive E. coli (AIEC) is a pathobiont frequently found in IBD biopsies. AIEC adhere to and invade epithelial cells, and can survive inside macrophages in vitro. However, how AIEC contributes to IBD in vivo remains unclear. Here a larval zebrafish (Danio rerio) model of AIEC was established, which facilitates the study of the …

Multiparametric Magnetic Resonance Imaging Artificial Intelligence Pipeline For Oropharyngeal Cancer Radiotherapy Treatment Guidance, Kareem Wahid

Dissertations & Theses (Open Access)

Oropharyngeal cancer (OPC) is a widespread disease and one of the few domestic cancers that is rising in incidence. Radiographic images are crucial for assessment of OPC and aid in radiotherapy (RT) treatment. However, RT planning with conventional imaging approaches requires operator-dependent tumor segmentation, which is the primary source of treatment error. Further, OPC expresses differential tumor/node mid-RT response (rapid response) rates, resulting in significant differences between planned and delivered RT dose. Finally, clinical outcomes for OPC patients can also be variable, which warrants the investigation of prognostic models. Multiparametric MRI (mpMRI) techniques that incorporate simultaneous anatomical and functional information …

Tissue-Specific Matrix Control Of Cell Cohesion And Migration Signaling Complexes, Tristen Tellman

Dissertations & Theses (Open Access)

The extracellular matrix (ECM) is a complex, interconnected network of three major constituents: collagens, glycoproteins, and proteoglycans, along with their enzyme modifiers. Within this network and beyond the structural role, each ECM molecule contributes a context-specific signal that influences cellular fate and behavior. Among these behaviors, cellular migration provides an essential function in developing tissues, wound healing, and cancer cell metastasis. Using two glandular organs, the normal salivary gland and the cancerous prostate, this dissertation describes the tissue-specific composition of two ECM signaling complexes (type I hemidesmosomes and the perlecan-semaphorin 3A-plexin A1-neuropilin-1 (PSPN) complex) and translates this knowledge into viable …

Integration Of Biomedical Imaging And Translational Approaches For Management Of Head And Neck Cancer, Abdallah Mohamed, Abdallah Mohamed

Dissertations & Theses (Open Access)

The aim of the clinical component of this work was to determine whether the currently available clinical imaging tools can be integrated with radiotherapy (RT) platforms for monitoring and adaptation of radiation dose, prediction of tumor response and disease outcomes, and characterization of patterns of failure and normal tissue toxicity in head and neck cancer (HNC) patients with potentially curable tumors. In Aim 1, we showed that the currently available clinical imaging modalities can be successfully used to adapt RT dose based-on dynamic tumor response, predict oncologic disease outcomes, characterize RT-induced toxicity, and identify the patterns of disease failure. We …

The Effect Of Cognitive Status And Residency On Oral Health In Patients With Dementia, Nicole Stephens

Dissertations & Theses (Open Access)

Poor oral health is a predictor of cognitive decline in elderly populations and has been shown to precede dementia. As cognitive decline progresses, patients are likely to move from the community into nursing facilities. We hypothesize that severity of dementia and residency type will impact the oral health of patients with dementia. Fifty-two participants of two dementia levels were recruited from the UTHealth Neurocognitive Disorders Center and two Houston-area nursing homes. A standardized oral health assessment, plaque index, and oral bacteria analysis determined participants’ oral health status. Further, data was collected on participants’ medical history, oral hygiene habits, dietary habits, …

Virulence And Biofilm Formation In Candida Albicans Are Inhibited By Short Peptide Subunits Of Entv, Shane Cristy

Dissertations & Theses (Open Access)

Candida albicans, the most clinically significant fungal pathogen, commonly causes topical mucosal infections such as oral cavity and urogenital tract infections. It also less frequently causes severe invasive and bloodstream infections. Invasive infections are most prevalent amongst patients with compromised innate immune responses, such as those receiving chemotherapy or recovering from surgery. C. albicans can also form biofilms on implanted medical devices. Fungal infections are difficult to treat due to the paucity of therapeutic options, and this problem is compounded by the resistance properties of biofilm infections.

Candida albicans exists as a member of the commensal flora of the …

Genetic Pathway Analysis Of Abnormal Facial Development In Nonsyndromic Cleft Lip And Palate, Lorena Maili

Dissertations & Theses (Open Access)

Nonsyndromic cleft lip with or without cleft palate (NSCLP) is the most common craniofacial birth defect resulting from incomplete fusion of the facial prominences during development, which leaves a gap in the lip, primary palate and/or the secondary palate. NSCLP affects 135,000 NSCLP newborns worldwide each year based on a birth prevalence of 1 per 700 live births. While surgical treatments have dramatically improved, many long-term health issues persist, imposing significant medical, psychosocial and economic burdens. Familial aggregation and segregation analyses suggest genetic contributions underlie NSCLP, but despite decades of study, only a small portion of the NSCLP genetic liability …

Development Of A Ct Metal Artifact Management Algorithm For Proton Therapy Planning (Ampp) For Head And Neck Cancer Patients, Daniela Branco

Dissertations & Theses (Open Access)

Purpose: Dental amalgams (high Z materials) are common sources of artifacts in Head and Neck (HN) images. Commercial artifact reduction techniques have been offered, but many are impractical, produce inaccurate CT images or are not clinically available, thus not widely implemented. The goal of this work is to use CT gantry tilts to develop and evaluate a stereoscopic HN metal artifact management algorithm and investigate its improvement in proton treatment planning.

Methods: The in-house CT metal artifact management method for proton planning (AMPP) uses two angled CT scans to generate a single image set with no metal artifacts posterior …

Development Of A Culinary Nutrition-Based Training For Dietitians And A Clinic-Based Nutrition Intervention To Improve Health Outcomes Among Low-Income Minority Patients, John Wesley Mcwhorter

Dissertations & Theses (Open Access)

Substantial evidence demonstrates the relations between a healthy dietary pattern rich in fruits, vegetables, and whole grains and a lower risk of chronic diseases including type 2 diabetes. Despite well supported studies, programs, and public health campaigns presenting the health benefits of consuming a healthy dietary pattern, most Americans fall far short of the recommendations. Further, the compounding effects of food insecurity and the consumption of energy-dense and nutrient-deficient foods disproportionately affect low income minority populations. Culinary medicine (CM) and food prescription programs are gaining popularity as tools for (1) decreasing food insecurity; (2) increasing personal agency; (3) promoting healthy …

Using Technology To Reduce Barriers In Community Health: An Intersection Between Broadband Access, Ehr & Telehealth Adoption In Federally Qualified Health Centers, Renita Madu

Dissertations & Theses (Open Access)

While Federally Qualified Health Centers (FQHCs) provide affordable, high quality, accessible and cost–effective primary health care to all individuals regardless of their inability to pay, patients continue to have difficulty accessing affordable primary care as well as broader specialty services that other patients may receive living near larger health systems and hospitals. Health information technology (HIT) serves as a cost-effective means to overcome barriers related to accessing care, particularly for individuals living in rural and remote areas. We examined if the key influencers of an FQHC’s structure, broadband access and/ or state and federal policies impacted the utilization of telehealth …

An Assessment Of Outpatient Clinic Room Ventilation Systems And Possible Relationship To Disease Transmission, Kristin G. King

Dissertations & Theses (Open Access)

The delivery of healthcare in the United States is shifting from a largely inpatient model to an outpatient services model, but the physical infrastructure for outpatient clinics or medical offices may not be as robust as inpatient hospitals regarding whole room ventilation requirements. Guidelines for the design of healthcare facilities and national standards for ventilation establish generally acceptable ventilation rates for outpatient clinics, but it is unclear if these standards are actually being integrated into these settings. Published peer reviewed literature indicates that inadequate ventilation rates can be a risk factor in airborne transmission of infectious diseases in outpatient clinics, …

The Health And Wellness Characteristics Of Food And Beverage Service Industry Workers In Austin, Texas: A Participatory Cross-Sectional Survey, Alexandria Abbott

Dissertations & Theses (Open Access)

Food and beverage service industry workers are prone to tobacco use, alcohol abuse, illicit drug use, and mental health conditions. These workers are also highly likely to not have health insurance. Despite the poor health outcomes that stem from these conditions, little to no empirical evidence currently exists to explain the factors that contribute to the poor health condition of the service industry workforce. This study used a cross-sectional online survey to gather preliminary information on the health and wellness condition of service industry workers over the age of 18 in Austin, Texas. Survey respondents revealed high rates of alcohol …

Alternative Carbon Utilization As A Virulence Determinant For Candida Albicans, Robert Williams

Dissertations & Theses (Open Access)

Candida albicans is a polymorphic unicellular fungus that has evolved to proficiently colonize and infect mammals. A common constituent of the microbiome in the GI tract, mouth, vagina, and skin, C. albicans is also an opportunistic pathogen capable of causing a variety of mucosal infections and the life-threatening disseminated candidiasis. Systemic C. albicans infections are a serious and growing issue; the fungus is the fourth most common cause of nosocomial bloodstream infections which has a mortality rate reaching 50%. As antifungal resistance continues to rise, it is critical that I understand the molecular basis of disseminated fungal infections.

The phagocytes …

Latino Perspectives In Childhood Fever Management: A Focused Ethnography, Darlene Acorda

Dissertations & Theses (Open Access)

Background: Fever is the most common presenting complaint in the pediatric setting. Latino parents have greater misconceptions and are less knowledgeable of fever compared to other groups. They are more likely to believe that fever can cause serious harm and to present to the emergency department for non-emergent illness. Latino health practices are heavily influenced by cultural beliefs, yet few studies have focused on parental fever perception in this rapidly growing population. It is estimated that by 2050, 32% of the U.S. child population will be of Latino descent. Understanding the Latino perspective is a critical first step to …

Mcp-1 Release Modulation Through Interaction Of Pulmonary Endothelial Cells And Mesenchymal Stromal Cells, Kaavya Giridhar

Dissertations & Theses (Open Access)

Background: Ischemic stroke is a leading cause of death and long-term disability

around the world. Current treatment options are limited to the administration of

tissue plasminogen activator (tPA) and/or endovascular therapy, administered within

a limited time window. However, cell-based therapies such as mesenchymal stromal

cells (MSCs) have increasingly shown great promise for ischemic stroke recovery

with some therapies already in various stages of clinical trials. Intravenous (IV)

administration of the MSCs leads to the entrapment of these MSCs in the lungs.

These entrapped MSCs interact with the pulmonary endothelial cells (PECs) and

could modulate the immune response through the release …

Investigating Medical Examiners' Practices: Genetic Evaluation For Fatal Acute Aortic Dissection, Bradley Power

Dissertations & Theses (Open Access)

Acute thoracic aortic dissection (TAD) is a life-threatening event with a hereditary component. Currently, pathogenic variants in 11 genes associated with aortic aneurysm and dissection predispose to a heritable form of disease thereby conferring an increased risk for TAD. Genetic testing plays a pivotal role not only in diagnosis, but also in risk stratification for relatives and medical management to prevent premature death from dissection. Due to its high fatality rate, medical examiners and coroners (ME/Cs) may be the first to identify TAD cases and initiate genetic testing for the decedent and at-risk relatives. ME/Cs were surveyed using three clinical …

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

Dissertations & 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 …

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

Dissertations & 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 …

Hiv-Related Discriminatlon And Cervical Cancer Screening In Zambia, Crystal J. Cazier

Dissertations & Theses (Open Access)

Background: The Republic of Zambia has the third-highest incidence of cervical cancer in the world, where approximately 700,000 women over age 15 are living with HIV. Women living with HIV (WLHIV) are at increased risk for cervical cancer. While literature suggests that discrimination is a barrier to HIV care, no studies have explored if discrimination experienced in HIV clinics is related to cervical cancer screening using nationally representative datasets. Objective: The primary objective of this study was to examine whether perceived discrimination by healthcare workers due to HIV status is related to having been screened for cervical cancer among WLHIV. …

Utilizing Temporal Information In The Ehr For Developing A Novel Continuous Prediction Model, Kang Lin Hsieh

Dissertations & Theses (Open Access)

Type 2 diabetes mellitus (T2DM) is a nation-wide prevalent chronic condition, which includes direct and indirect healthcare costs. T2DM, however, is a preventable chronic condition based on previous clinical research. Many prediction models were based on the risk factors identified by clinical trials. One of the major tasks of the T2DM prediction models is to estimate the risks for further testing by HbA1c or fasting plasma glucose to determine whether the patient has or does not have T2DM because nation-wide screening is not cost-effective.

Those models had substantial limitations on data quality, such as missing values. In this dissertation, I …

Assessment Of The Common Dental Needs And Evaluation Of Rate Of Attendance Post Emergency Dental Management Among The Homeless Population In Houston, Texas, Heera Govindarajan Venguidesvarane

Dissertations & Theses (Open Access)

Background: Dental care resources for the homeless population are scarce, underfunded and generally inadequate to meet their oral health needs. While poor oral health is clearly an added burden for people who struggle daily to survive under miserable living conditions, little is known about their views on dental health, their perceived needs and their attitudes towards dental care. The purpose of this study was to determine the most common oral health needs of homeless patients and to identify their participation in receiving comprehensive care. Methods: The study was a cross sectional analysis where data were collected retrospectively using the records …

Additional Healthcare Expenditures Of Depression For Elderly Cancer Patients With Depression, Dian Gu

Dissertations & Theses (Open Access)

The risk of depression is high for cancer patients and a large portion of cancer patients are age 65 and over. Both depression and cancer are economically burdensome and depression is associated with healthcare expenditure increase for elderly patients. However, whether comorbid depression affects healthcare expenditures in elderly cancer patients from payers’ and patients’ perspectives is largely unknown. Objective: To investigate whether depression is associated with higher healthcare expenditure among elderly cancer patients from both payers’ and patients’ perspectives and, and determine whether depression is associated with higher probability of having high out-of-cost burden. Methods: From the Medicare Current Beneficiary …

The Prevalence Of Practicing Safety Professionals’ Knowledge, Involvement, And Competency Associated With Workplace Wellness Programs: Gauging The Safety Profession’S Engagement With The Total Worker Health Initiative, Jennifer C. Laine

Dissertations & Theses (Open Access)

The morbidity and mortality burden of occupational injuries and illnesses in the United States became such a public health concern that in 1970 the Occupational Safety and Health Act was signed into law. This law requires employers to provide workplaces “free from recognized hazards” and spurred the development of specific regulations along with the creation of academic and professional training programs to educate individuals about the safety sciences and careers in safety fields. Today there are an estimated 26,000 professionally trained and board certified safety professionals supporting workplace programs across the country, alongside numerous non-certified, but degreed, practicing safety professionals. …

Evaluating Religiosity Across The Lifespan And Fatalistic Beliefs Among Patients Of A Chronic Care Management Intervention Program With Type 2 Diabetes, Cindy Lynn Salazar

Dissertations & Theses (Open Access)

The overall goal of the present study was to assess the effect of fatalistic beliefs and lifetime religiosity on glycemic control and blood sugar monitoring behavior among Mexican-American participants of a chronic care management intervention program of the Rio Grande Valley. In order to achieve these aims, a mixed methods prospective longitudinal study design was utilized among approximately 500 participants of the Salud y Vida program. Qualitatively, a phenomenological approach was used to analyze semi-structured interview data assessing fatalism and religiosity and type 2 diabetes management among 15 participants stratified by engagement in the Salud y Vida program. Fatalistic beliefs …

Quantitative Imaging For Precision Medicine In Head And Neck Cancer Patients, Rachel Ger

Dissertations & Theses (Open Access)

The purpose of this work was to determine if prediction models using quantitative imaging measures in head and neck squamous cell carcinoma (HNSCC) patients could be improved when noise due to imaging was reduced. This was investigated separately for salivary gland function using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI), overall survival using computed tomography (CT)-based radiomics, and overall survival using positron emission tomography (PET)-based radiomics. From DCE-MRI, where T1-weighted images are serially acquired after injection of contrast, quantitative measures of diffusion can be obtained from the series of images. Radiomics is the study of the relationship of voxels to …

The Impact Of The Aca Cost-Sharing Elimination Provision On The Utilization Of Breast, Cervical, And Colorectal Cancer Screening Services Among Insured Individuals In The United States, Sara Salah Atallah

Dissertations & Theses (Open Access)

Preventive cancer screenings are essential to early detect cancer and subsequently save lives. However, out-of-pocket expenditures for cancer screening services deter individuals from obtaining them. In an effort to improve the utilization of cancer screening, the Affordable Care Act (ACA) implemented a cost-sharing elimination provision that removes all forms of cost sharing including copayments, co-insurance and deductibles from certain preventive care services that are recommended by widely known scientific figures such as the United States Preventive Services Task Force (USPSTF). This study evaluated the impact of the ACA cost-sharing elimination provision for preventive care services from 2008 through 2016 using …

Quantifying The Impact Of Laboratory And Care Systems On Relinkage To Hiv Care In A Southern, Urban Environment, Kellie L. Watkins

Dissertations & Theses (Open Access)

Background: HIV viral suppression reduces the likelihood of transmission to just 5%,1 demonstrating the critical link between care and prevention, yet only 51% of people living with HIV (PLWH) were retained in care and 46% achieved viral suppression in the Houston area (2012), with the out-of-care (OOC) population increasing between 2008-2011.2,3

Methods: Record-search investigations across HIV surveillance and care data systems determined if potentially OOC persons referred to the Houston Health Department (HHD) from 2013-2015 (N=1287) qualified for public health follow up. A portion were randomized to a non-intervention group (n=200) to assess the program effectiveness. Participants without a disposition …

Insights Into The Reactivation, Regulation And Essentiality Of Oxidative Protein Folding Pathways In Actinobacteria, Belkys Sanchez

Dissertations & Theses (Open Access)

Accurate disulfide bond formation is important for proper folding, stability and function of exported proteins. The process of disulfide bond formation, termed oxidative protein folding, is catalyzed by thiol-disulfide oxidoreductase enzymes. Oxidative protein folding pathways influence processes essential for bacterial physiology and pathogenicity. In the Gram-positive actinobacterial pathogens Actinomyces oris and Corynebacterium diphtheriae oxidative protein folding is catalyzed by the primary thiol-disulfide oxidoreductase MdbA. MdbA is required for assembly of adhesive pilus, which mediate receptor-dependent bacterial interactions, or coaggregation, in A. oris. In the first part of this dissertation, I identify components of the electron transport chain (ETC) required for …

Investigation Of Novel Virulence Mechanisms In Candida Albicans, Elisa Marie Tafoya Vesely

Dissertations & Theses (Open Access)

Candida albicans is the most important fungal species associated with humans. Normally present in the human microbiome as a commensal colonizer, C. albicans is also the fourth most prevalent organism isolated from bloodstream infections in hospitals. Disseminated infections have an associated mortality rate of around 40%. The results of the work described in this dissertation cover the broad subject of C. albicans adaptation to the host and the mechanisms by which this organism is able to survive and cause infection through a variety of means. A key determinant in disease progression is interaction with innate immune cells, specifically macrophages and …

Assembly And Display Of Surface Proteins In Actinomyces Oris, Sara Siegel

Dissertations & Theses (Open Access)

Bacteria are an integral part of human health and disease. In the human host, dental plaques form as a result of up to 700 individual bacterial species colonizing oral surfaces and forming a multispecies biofilm. These biofilms are the cause of prevalent human diseases such as dental caries, gingivitis, and periodontitis. The microbes present in the oral biofilm are highly spatially and temporally structured and require a primary colonizing species to adhere to host tissue. As an important primary colonizer of the oral biofilm, the actinobacterium Actinomyces oris utilizes cell wall anchored proteins and glycoconjugates to initiate adherence to host …