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Tnf Signaling During Tissue Damage-Induced Nociceptive Sensitization In Drosophila, Juyeon Jo

Dissertations and Theses (Open Access)

Tumor necrosis factor (TNF) signaling is required for inflammatory nociceptive sensitization in both Drosophila and vertebrates. In Drosophila larval model of nociceptive sensitization, UV irradiation in results in epidermal apoptosis and thermal allodynia. TNF/Eiger is produced from dying epidermal cells and acts its receptor in nociceptive sensory neurons to induce thermal allodynia. Inhibition of TNF signaling results in attenuation of nociceptive sensitization whereas epidermal apoptosis still occurs in the absence of TNF. Major gaps in this model are the precise relationship between apoptotic cell death and production of TNF/Eiger, downstream signaling mediators for TNFR/Wengen, and target genes that alter nociceptive …

Employing T Cells For Antigen Presentation: Role Of Ny-Eso-1+ T-Apc Vaccine In Multiple Myeloma, Krina K. Patel

Dissertations and Theses (Open Access)

Introduction: Cellular therapy has shown great potential in early phase clinical trials with persistence of effector cells appearing to lead to improved outcomes. Combined immunotherapy with NY-ESO-1⁺ CAR T cells (TCR mimetic) and an NY-ESO-1 specific T-APC vaccine in myeloma patients may lead to enhanced anti-myeloma efficacy due to improved persistence of the CAR T cells.

Materials and Methods: Using the Sleeping Beauty transposon/transposase system, an NY-ESO-1⁺ TCR and CAR were created as effector cells. Vaccine was produced by electroporation of the NY-ESO-1 gene into T cells to make T cell antigen presenting cells (T-APC). Costimulatory …

Understanding The Mechanism And Extent Of Vlse Recombination In Borrelia Burgdorferi Using Next-Generation Sequencing, Surabhi Tyagi

Dissertations and Theses (Open Access)

B. burgdorferi, the causative agent of Lyme disease, have an elaborate antigenic variation system that involves varying the sequence of vlsE. Previous studies have shown that vlsE antigenic variation occurs continuously inside mammalian hosts. Variation has not been shown previously to occur in in vitro or in ticks. We hypothesized that the induction of vlsE recombination requires contact with dense arrays of host tissue cells and/or ECM components. To test this hypothesis, two methods, quantitative PCR and high-throughput sequencing were used determine the extent and nature of vlsE recombination within mouse tissues and in vitro model systems. Using these …

Function And Mechanism Of Alkbh5 In N6-Methyl-Adenosine Rna Modification In Glioblastoma, Sicong Zhang

Dissertations and Theses (Open Access)

N⁶-methyl-adenosine (m⁶A) is the most prevalent internal chemical modification of mRNAs in eukaryotes. In mammals, m⁶A installed by m⁶A methyltransferases METTL3 and METTL14 is erased by two members of the AlkB family of nonheme Fe(II)/a-ketoglutarate (a-KG)-dependent dioxygenases, fat-mass and obesity associated protein (FTO) or ALKBH5. ALKBH5 affects nuclear RNA export and metabolism, gene expression and mouse fertility. To date, little is known about the biological significance of m⁶A in human cancer. We found that ALKBH5 is highly expressed in human glioblastoma stem cells which are resistant to conventional therapy and …

Novel Mechanisms Of Β-Adrenergic Signaling In Prostate Cancer Progression, Mohit Hulsurkar

Dissertations and Theses (Open Access)

Prostate cancer is the second leading cause of cancer death among American men. The American Cancer Society estimates that 180,890 men will be will be diagnosed with prostate cancer in 2016 in the USA. (http://www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-key-statistics). Androgen deprivation therapy (ADT) is the standard treatment for early stage prostate cancer. But most patients relapse with aggressive variants of prostate cancer, with survival time between 1-3 years. In order to develop cure for such aggressive variants of prostate cancer, our present understanding of the mechanisms underlying its progression needs to be advanced.

Recently, it has been found that activation of β-adrenergic signaling pathway …

Endocarditis And Incomplete Endothelialization 12 Years After Amplatzer Septal Occluder Deployment, Allan K Nguyen, Brian A Palafox, Joanne P Starr, Richard N Gates, Farbouch Berdjis

The Texas Heart Institute Journal

A 4-year-old boy had a 15-mm atrial septal defect repaired percutaneously with use of an Amplatzer Septal Occluder. At age 16 years, he presented with a week's history of fever, chills, dyspnea, fatigue, and malaise. Cultures grew methicillin-sensitive Staphylococcus aureus. A transesophageal echocardiogram showed a 1.25 × 1.5-cm pedunculated mass on the left aspect of the atrial septum just superior to the mitral valve, and a smaller vegetation on the right inferior medial aspect of the septum. At surgery, visual examination of both sides of the septum revealed granulation tissue, the pedunculated mass, the small vegetation, and exposed metal …

Implications Of Computational Cognitive Models For Information Retrieval, Joshua Caleb Goodwin

Dissertations and Theses (Open Access)

This dissertation explores the implications of computational cognitive modeling for information retrieval. The parallel between information retrieval and human memory is that the goal of an information retrieval system is to find the set of documents most relevant to the query whereas the goal for the human memory system is to access the relevance of items stored in memory given a memory probe (Steyvers & Griffiths, 2010).

The two major topics of this dissertation are desirability and information scent. Desirability is the context independent probability of an item receiving attention (Recker & Pitkow, 1996). Desirability has been widely utilized in …

Information Processing Speed Impairment After Stroke, A Descriptive Study, Susan Alderman

Dissertations and Theses (Open Access)

Background Information processing speed (IPS) is an elemental cognitive function impacting multiple other functions including memory, attention, and executive function, and academic skills like arithmetic, reading and writing. However, little research has been done on IPS impairment in acute stroke. This article compares the frequency and severity of IPS impairment in mild and moderate stroke and its impact on quality of life.

Methods The longitudinal study of patients with mild stroke (NIHSS

Results Using linear mixed model regression, similar frequency and severity of IPS and memory impairments were noted, regardless of stroke severity, in the sample of 30 patients (60% …

Lipocalin 2 Promotes The Establishment Of A Pro-Tumorigenic Microenvironment In Pancreatic Cancer, Sobeyda B. Gomez-Chou

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a disease characterized by a dismal prognosis with a 5-year survival rate of 7%. A unique hallmark of this disease is an abundant desmoplastic reaction that can account for up to 90% of the solid tumor volume. Key components of the PDAC stroma include the extracellular matrix (ECM) rich in collagen type I and III, activated pancreatic stellate cells (PSCs) and inflammatory cells such as neutrophils and macrophages. The main line of evidence has suggested a pro-tumorigenic role for the PDAC stroma as it has been shown to help enhance tumor growth, invasive potential and …

Ethnic Identity And Teratogenic Risk Perceptions, Katie M. Chan

Dissertations and Theses (Open Access)

Elevated perceptions of teratogenic risk can cause anxiety and confusion among pregnant women. To assess whether ethnic identity and demographic factors can influence teratogenic risk perceptions, 194 pregnant women in Houston were surveyed using the Multigroup Ethnic Identity Measure (MEIM) and visual analog scales to quantify perceptions of teratogenic risk for common exposures during pregnancy. Overall, participants estimated an elevated baseline risk of 25% for birth defects among the general population. In addition, participants overestimated birth defect risks for specific exposures, such as alcohol and marijuana. Based on the MEIM scores, ethnic identity was not significantly associated with teratogenic risk …

Insights Into Determinants That Contribute To Colonization, Virulence And Antibiotic Resistance In Enterococci, Maria Camila Montealegre

Dissertations and Theses (Open Access)

Enterococcus faecalis and Enterococcus faecium are increasingly common as causative agents of human infections, many of which are very difficult to treat due to multi-drug resistance. The work presented in the first part of this dissertation elucidates a mechanism for the regulation of pilus expression. I showed that ATT is the initiation codon of ebpA, the first gene of an operon that codes for the endocarditis and biofilm-associated pili (Ebp), a recognized virulence factor in E. faecalis. The presence of this rare start codon downregulates EbpA translation and protein levels, diminishing biofilm and binding abilities of …

Network Dynamics Of Visual Object Recognition, Mehmet C. Kadipasaoglu

Dissertations and Theses (Open Access)

Visual object recognition is the principal mechanism by which humans and many animals interpret their surroundings. Despite the complexity of neural computation required, object recognition is achieved with such rapidity and accuracy that it appears to us almost effortless. Extensive human and non-human primate research has identified putative category-selective regions within higher-level visual cortex, which are thought to mediate object recognition. Despite decades of study, however, the functional organization and network dynamics within these regions remain poorly understood, due to a lack of appropriate animal models as well as the spatiotemporal limitations of current non-invasive human neuroimaging techniques (e.g. fMRI, …

Poly (Adp) Ribose Polymerase Inhibitors For The Treatment Of Malignant Peripheral Nerve Sheath Tumor, Christine M. Kivlin

Dissertations and Theses (Open Access)

Malignant peripheral nerve sheath tumor (MPNST) is a rare subtype of soft tissue sarcoma. Surgical excision has remained the standard of care for this highly aggressive malignancy for over a decade. Conventional chemotherapy and radiotherapy have shown limited efficacy in MPNST; therefore, it is imperative that targeted treatment be identified to improve the outcome for MPNST patients. Poly (ADP) ribose polymerase (PARP) inhibitors were first reported over a decade ago to have substantial anti-tumorigenic effects in malignancies with defective DNA repair, specifically those with BRCA1/2 (breast cancer, early onset 1/2) mutations. Further evaluation of these inhibitors has shown multiple mechanisms …

Mechanisms Of Regulation Of Tau Ires Mediated Translation, Niza Nemkul

Dissertations and Theses (Open Access)

The translation of most eukaryotic mRNAs occurs in a cap-dependent manner. However, a subset of mRNAs are capable of initiating translation in a cap-independent manner by utilizing sequences in their 5’ UTR called IRES. It was previously shown that the 5’ UTR of the tau mRNA contains an IRES. In this study I show that IRES dependent translation of tau IRES is regulated at multiple levels in order to regulate the expression of the tau protein.

Tau protein is ubiquitously expressed but is concentrated in the brain. In this study, I utilized neural and non-neural cell lines to show that …

Characterization Of Stem Cell Turnover In A Living Epithelial Bilayer, Elizabeth Sumner

Dissertations and Theses (Open Access)

Homeostatic maintenance of epithelia requires the renewal and replacement of old or dying cells while sustaining a functional barrier. Imbalance between cell production and elimination are hypothesized to underlie many pathological conditions. However, our knowledge of cell turnover within living tissues remains largely restricted to static images due to the limited ability to study epithelia in their native context. Here we report that clearance of damaged basal stem cells promotes compensatory proliferation of neighboring stem cells to maintain overall population numbers in a bilayered epithelium. Time-lapse imaging and electron microscopy experiments reveal that dying cells are rapidly cleared as nearby …

The Thioredoxin Trx-1 Regulates The Major Oxidative Stress Response Transcription Factor, Skn-1, In Caenorhabditis Elegans, Katie C. Mccallum

Dissertations and Theses (Open Access)

The ability to respond to hostile environmental conditions is critical for the survival of an organism. Oxidative stress is an adverse state in which reactive oxygen species (ROS) accumulate to a harmful level and, if left unresolved, can lead to cellular dysfunction and organismal disease. Sophisticated detoxification systems, characterized by a battery of enzymatic antioxidants, are utilized to neutralize ROS thereby reducing stress. However, ROS are also purposefully produced by designated cellular enzymes to facilitate the signaling and regulation of critical physiological processes. Therefore, both the production and neutralization of ROS must be tightly controlled. Indeed, the expression of detoxification …

The Roles Of Malt1 In Nf-Κb Activation And Solid Tumor Progression, Deng Pan

Dissertations and Theses (Open Access)

The transcription factor NF-κB plays a central role in many aspects of biological processes and diseases, such as inflammation and cancer. Although it has been suggested thatNF-κB is critical in tumorigenesis and tumor progression, the molecular mechanism by which NF-κB is activated in solid tumor remains largely unknown. In the current work, we focus on growth factor receptor-induced NF-κB activation and tumor progression, including epidermal growth factor receptor (EGFR)-induced NF-κB in lung cancer and heregulin receptor (HER2)-induced NF-κB in breast cancer. We found that Mucosa-associated lymphoma translocation protein 1 (MALT1), also known as paracaspase, is required for EGFR-induced NF-κB activation …

Trim24 Orchestrates Metabolic Reprogramming And Emt In Breast Cancer, Kaushik Thakkar

Dissertations and Theses (Open Access)

In this dissertation, I report the oncogenic functions of an epigenetic regulator Tripartite Motif Protein 24 (TRIM24) coupled with metabolic reprogramming and epithelial mesenchymal transition (EMT) in breast cancer. TRIM24 was first established by our laboratory as a previously unknown negative regulator of p53 via its RING domain, as a co-regulator of nuclear receptors and a PHD/Bromodomain reader of specific histone modifications. TRIM24 expression correlates with poor prognosis of breast cancer, but the mechanisms of TRIM24-mediated oncogenesis are unknown. In the first part of my thesis, I found that TRIM24 is aberrantly expressed in early stages of breast cancer progression. …

The Role Of Amp-Activated Protein Kinase (Ampk) In Tumorigenesis, Fei Han

Dissertations and Theses (Open Access)

AMPK plays a central role in controlling cellular and whole body energy level. Increasing studies have also discovered the diverse function of AMPK in cancer, such as autophagy and mitochondria biogenesis. However, how AMPK promotes cancer progression is still not clear. Here, we show that AMPK is essential for EGF-induced Akt activation, Glut1 expression, and glucose uptake. AMPK is also required for various stresses induced Akt activation and promote cell survival, including hypoxia and glucose deprivation. In addition, we found glucose deprivation-induced VEGF expression and secretion is also depend on AMPK, which may contribute to angiogenesis of surrounding endothelial cell …

The Role Of Gdf15 In Ovarian Cancer, Daisy I. Izaguirre

Dissertations and Theses (Open Access)

Growth Differentiation Factor 15 (GDF15) is induced in situations such as stress, inflammation, treatment with non-steroidal anti-inflammatory drugs, as well as other therapeutic agents. As a secreted protein, GDF15 is seen as a potential biomarker in several types of cancer as well as in other diseases such as cardiovascular diseases, diabetes, and rheumatoid arthritis. In ovarian cancer, high GDF15 serum levels correspond to poor survival. It has further been shown to be expressed at higher levels in serum in ovarian cancer patients post-chemotherapy than pre-chemotherapy.

The overall 5-year survival for ovarian cancer is 46%, as a result of late diagnosis …

Preeclampsia: The Roles Of Acute Inflammation And Intrauterine Stress, Nicholas Parchim

Dissertations and Theses (Open Access)

Preeclampsia (PE) is a severe, acute disease of pregnancy affecting approximately 8% of pregnant women after week 20 of gestation. PE is characterized by hypertension and renal damage reflected by proteinuria and has significant morbidity to both mother and fetus. Maternal symptoms range from headaches, nausea, edema, to visual changes, but once maternal symptoms present, damage to the fetus has begun. Mothers who progress untreated through the disease can also experience a condition called eclampsia characterized by seizure, coma, and, ultimately, death. PE-affected newborns experience features similar to prematurity—abnormal lung and renal development, intrauterine growth retardation (IUGR), and, possibly, fetal …

The Novel Regulation Of Histone Modification In Cancer Development, Xian Zhang

Dissertations and Theses (Open Access)

Dynamic changes in histone acetylation by various physiological cues play important roles in gene transcription and cancer. However, the cellular signaling underlying this regulation is not well understood. Here, we show that, in a glucose dependent manner, E3 ubiquitin ligase NEDD4 ubiquitinates histone H3 on previously unstudied lysine (K) 23/36/37 residues, which specifically recruits histone acetyltransferase (HAT) GCN5 for subsequent H3 acetylation. Genome-wide analysis of chromatin immunoprecipitation followed by sequencing (ChIP-seq) data sets reveals that NEDD4 regulates glucose-induced H3K9 acetylation at transcription starting site (TSS) and enhancer regions. Integrative analysis of ChIP-seq and microarray data sets also reveals a consistent …

Characterization Of The Ato Gene Family In Alternative Carbon Metabolism, Heather A. Danhof

Dissertations and Theses (Open Access)

As a commensal colonizer and opportunistic pathogen, Candida albicans is the most clinically important human associated fungus. Systemic infection carries an unacceptably high mortality rate of ~40% in the growing population of immunocompromised individuals. Macrophages are important innate immune cells that limit the niches in the human body in which C. albicans can persist through phagocytic removal. However, following phagocytosis C. albicans readily escapes from the immune cell by differentiating into filamentous hyphae, a process that should be inhibited in the normally acidic phagolysosome. We have shown that C. albicans induces germination by neutralizing the phagolysosome. To better understand this …

Gsk3Beta-Mediated Ezh2 Phosphorylation Suppresses Methylation Of H3k27 And Ezh2’S Oncogenic Functions, How-Wen Ko

Dissertations and Theses (Open Access)

During the process of tumorigenesis, inactivation of tumor suppressors is a critical step. Enhancer of zeste homolog 2 (EZH2), a histone methyltransferase and the enzymatic core subunit of polycomb repressive complex 2 (PRC2), promotes cell growth and migration through catalyzing trimethylation of histone H3 at Lys 27 (H3K27me3) and plays an important role in tumorigenesis. Its expression can be controlled by phosphorylation. However, the regulation of EZH2 activity by tumor suppressor kinase is not well understood. Glycogen synthase kinase 3 beta (GSK3b), a multifunctional serine/threonine kinase, is involved in many cellular processes. GSK3b also participates in neoplastic transformation, tumor development …

In Vivo Kinome Screen Reveals Non-Canonical Cdk-Driven Metabolic Adaptation In Brain Metastasis, Frank J. Lowery Iii

Dissertations and Theses (Open Access)

Brain metastasis, which frequently arises from breast cancer, lung cancer, melanoma, and colorectal cancer, remains a severely unmet medical need and its incidence continues to rise while treatment options remain palliative. To better understand the biology underlying its aggressive, incurable nature, I performed an unbiased in vivo kinome screen to identify potential driver kinases of experimental brain metastasis in a nude xenograft model using the human breast cancer cell line MDA-MB-231. Several of the kinase pools led to decreased brain metastasis-specific survival in nude mice, shortening survival time by up to 50% relative to controls. Targeted next-generation sequencing (NGS) was …

Clinical And Demographic Variables Associated With Cognitive Deficits, Symptom Severity, And Duration After Concussive Injury In Adolescents: A Retrospective Study, Seema S. Aggarwal

Dissertations and Theses (Open Access)

Background: Concussions in adolescents are a public health concern with the growing popularity of high school sports. Recent legislation mandates that athletes who are suspected of a concussion be cleared to return-to-play by a clinician. More research is needed to develop a concussion predictive model to identify populations at risk for more severe and prolonged symptoms and long-term neurologic deficits.

Aims: The aims of this study were to (1) examine the effect of race and gender on neurocognitive and symptom scores and (2) determine which clinical (e.g., number of concussions, migraine history, learning disabilities/ attention deficit disorders) and demographic factors …

Biventricular Myocardial Performance Is Impaired In Proportion To Severity Of Obstructive Sleep Apnea, Selahattin Akyol, Mustafa Cortuk, Ahmet Oytun Baykan, Kemal Kiraz, Abdurrezzak Borekci, Taner Seker, Mustafa Gur, Murat Cayli

The Texas Heart Institute Journal

Obstructive sleep apnea (OSA) is an independent risk factor for cardiovascular morbidity and death. Little information is available regarding the relationship between the severity of OSA and myocardial performance in OSA patients who have normal ejection fractions. We prospectively investigated this relationship, using the tissue-Doppler myocardial performance index (TD-MPI).

We conducted overnight, full-laboratory polysomnographic examinations of 116 patients, and calculated the left and right ventricular TD-MPIs. Patients were classified into 3 groups in accordance with their apnea-hypopnea index (AHI) levels: AHImild (≥5 to <15), AHImoderate (≥15 to <30), and AHIsevere (≥30).

Left and right ventricular TD-MPI values were higher in the AHIsevere group than in the AHImild and …

Explicit Time Deficit In Schizophrenia: Systematic Review And Meta-Analysis Indicate It Is Primary And Not Domain Specific, V Ciullo, G Spalletta, C Caltagirone, Re Jorge, F Piras

Faculty, Staff and Students Publications

Although timing deficits are a robust finding in schizophrenia (SZ), the notion of a genuine time perception disorder in SZ is still being debated because distortions in timing might depend on neuropsychological deficits that are characteristics of the illness. Here we used meta-analytic methods to summarize the evidence of timing deficits in SZ and moderator analyses to determine whether defective timing in SZ arises from nontemporal sources or from defective time perception. PubMed Services, PsycNET, and Scopus were searched through March 2015, and all references in articles were investigated to find other relevant studies. Studies were selected if they included …

Genome Engineering: Drosophila Melanogaster And Beyond, Kjt Venken, A Sarrion-Perdigones, Pj Vandeventer, Ns Abel, Ae Christiansen, Kl Hoffman

Faculty, Staff and Students Publications

A central challenge in investigating biological phenomena is the development of techniques to modify genomic DNA with nucleotide precision that can be transmitted through the germ line. Recent years have brought a boon in these technologies, now collectively known as genome engineering. Defined genomic manipulations at the nucleotide level enable a variety of reverse engineering paradigms, providing new opportunities to interrogate diverse biological functions. These genetic modifications include controlled removal, insertion, and substitution of genetic fragments, both small and large. Small fragments up to a few kilobases (e.g., single nucleotide mutations, small deletions, or gene tagging at single or multiple …

Ms171: Interview With Huda Zoghbi, Huda Zoghbi Md, Houston Academy Of Medicine-Texas Medical Center Library

Texas Medical Center - Women's History Project

An oral history interview with Dr. Huda Zoghbi about her career at Baylor College of Medicine in the Texas Medical Center. She worked as a professor in the Departments of Pediatrics, Molecular and Human Genetics, Neurology and Neuroscience at Baylor College of Medicine. She was also an investigator at the Howard Hughes Medical Institute and the director of the Jan and Dan Duncan Neurological Research Institute (NRI) at Texas Children's Hospital. See more at Texas Medical Center-Women's History Project and its finding aid.

SOURCE: Baylor College of Medicine website, http://www.bcm.edu