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Dhhc5 Regulates Beta-Adrenergic Signaling In The Heart Through Palmitoylation Of G Alpha Proteins, Jie Chen

Dissertations and Theses (Open Access)

S-palmitoylation is a reversible posttranslational modification that plays an important role in regulating protein localization, trafficking, and stability. Recent studies have shown that some proteins undergo extremely rapid palmitoylation/depalmitoylation cycles after cellular stimulation supporting a direct signaling role for this posttranslational modification. The work in this dissertation investigated whether β-adrenergic stimulation led to stimulus-dependent palmitoylation of downstream signaling proteins in immortalized and primary cell models. I found that β-adrenergic stimulation led to rapidly increased Gαs and Gαi palmitoylation only in primary cardiomyocytes. The kinetics of palmitoylation was temporally consistent with the downstream production of cAMP and contractile responses. I identified …

Obscurin Mediates Ankyrin Complex Formation In The Heart, Janani Subramaniam

Dissertations and Theses (Open Access)

Distinctly organized domains of receptors, ion channels, transporters, signaling molecules, cell adhesion molecules, and contractile proteins are crucial to cardiac function. Interactions between adaptor proteins such as ankyrins and cytoskeletal proteins such as obscurin play a pivotal role in organizing these functional domains in cardiomyocytes. Therefore, dysfunction of both ankyrin as well as obscurin lead to a host of cardiovascular diseases such as arrhythmias and cardiomyopathies. Alternative splicing of ankyrin yields numerous isoforms that interact with obscurin at various sub-cellular domains. And while some of these obscurin-ankyrin complexes have been studied, many others have not been characterized. Further, previous studies …

Tracking Treatment Response And Resistance To Parp Inhibition (Talazoparib) In Hereditary Pancreatic Cancer., Jennifer Goldstein

Dissertations and Theses (Open Access)

polyADP ribose polymerase (PARP) inhibitors are a class of drugs that block the PARP enzymes, involved in the repair of singe-stranded DNA breaks through the base excision repair pathway. PARP inhibition leads to replication-associated double stranded DNA breaks, which are repaired by homologous recombination (HR). In tumors with HR defects (i.e. BRCA mutants), there is a shift to error-prone DNA repair and subsequent genomic instability and cell death.

In 2014, Olaparib became the first FDA-approved PARP inhibitor for the treatment of BRCA-mutant ovarian cancer. In the phase III POLO (Pancreas cancer OLaparib Ongoing) trial presented at the American Society …

Bilirubin Nanoparticle As An Anti-Inflammatory Therapy For Graft Versus Host Disease, Sumedha Pareek

Dissertations and Theses (Open Access)

Graft versus host disease (GvHD) caused by alloreactive donor lymphocytes is a fatal complication of hematopoietic stem cell transplant (HSCT). Myeloablative conditioning regimen, consisting of chemotherapy and/or radiation, given prior to HSCT can cause tissue damage. This non-specific tissue damage triggers cross-presentation of alloantigens to the donor immune cells, causing recruitment of leukocytes and production of inflammatory cytokines. Targeting this inflammation without affecting the anti-leukemia effects of HSCT, continues to be one of the biggest challenge in finding a therapy for GvHD. Bilirubin is a tetrapyrrole pigment, found in the blood, with natural anti-oxidative and anti-inflammatory properties. Using mouse models …

Role Of Nudt21 Mediated Alternative Polyadenylation And Hyaluronan In The Development Of Pulmonary Hypertension, Scott Dale Collum

Dissertations and Theses (Open Access)

Pulmonary hypertension (PH) is a progressive disease with serious effects on quality of life and life expectancy of patients. PH is a complex disease that likely develops due to multiple influences, and no curative treatments exist for this disease. It has been shown that alternative polyadenylation (APA) due to depletion of Nudix Hydrolase 21(NUDT21) is involved in several disease states including the chronic lung disease idiopathic pulmonary fibrosis (IPF). Additionally, hyaluronan, an extracellular matrix glycosaminoglycan has been associated with PH. The role and mechanism of NUDT21 and hyaluronan have not yet been described in this disease. My results reveal that …

Investigations Of The Structure-Function Relationship In Kainate Receptors Using FöRster Resonance Energy Transfer, Douglas Litwin

Dissertations and Theses (Open Access)

Kainate receptors belong to the family of ion channels known as the ionotropic glutamate receptors. Ionotropic glutamate receptors mediate the majority of excitatory synaptic transmission, modulate the release of presynaptic glutamate, and facilitate dendrite formation. Kainate receptors are unique among the ionotropic glutamate receptors in being modulated by sodium ions. They have also been implicated in the development of higher learning and epilepsy. In recent years a wealth of structural data has become available for the AMPA and NMDA classes; however, the structural characterization of kainate receptors has been limited. The work in this dissertation utilizes luminescence resonance energy transfer …

Modeling Cancer Using Li-Fraumeni Syndrome Patient-Derived Induced Pluripotent Stem Cells, Ruoji Zhou

Dissertations and Theses (Open Access)

Li-Fraumeni syndrome (LFS) is an autosomal dominant disease caused by germline mutations in the gene TP53, which predispose individuals to a wide range of malignancies, including osteosarcoma and breast cancer. In the previous study, our group developed a novel disease model platform by reprograming LFS patients' fibroblasts to induced pluripotent stem cells (iPSCs), and further differentiate these iPSCs into mesenchymal stem cells (MSCs) then to osteoblasts (OBs), the cells from which osteosarcomas originate. Interestingly, LFS iPSC-derived osteoblasts recapitulated the osteosarcoma phenotype, creating “a bone tumor in a dish”. This “tumor in a dish” platform proved that LFS is an …

Deubiquitinating Enzymes Promote Cancer Progression And Metastasis Via Regulating Protein Stability, Zhenna Xiao

Dissertations and Theses (Open Access)

Deubiquitinating enzymes (DUBs, also called deubiquitinases) are enzymes that remove monoubiquitin or polyubiquitin chains from target proteins. DUBs have critical roles in cell homeostasis and signal transduction, as they regulate protein degradation, subcellular localization, and protein-protein interaction. Deregulation of DUBs contributes substantially to tumor formation and progression, and therefore targeting DUBs may be a promising cancer therapy strategy. My dissertation focuses on identifying the DUBs of EZH2 and SNAI1, two proteins critical for cancer progression and metastasis, and establishing these DUBs as promising anti-cancer targets.

EZH2, the catalytic component of the PRC2 complex, silences gene transcription by histone methylation. High …

Quantifying Uncertainty In A Measurement-Based Assessment Of Relative Biological Effectiveness In Carbon Ion Radiotherapy, Shannon Hartzell

Dissertations and Theses (Open Access)

One of the largest inconsistencies in dose delivered during carbon ion therapy is due to uncertainties in relative biological effectiveness (RBE), a value that is calculated via one of several clinically implemented algorithms. This study investigates the uncertainty in measured microdosimetric parameters for RBE calculation by the Microdosimetric Kinetic Model (MKM), Repair Misrepair Fixation model (RMF), and Local Effect Model I (LEM) using a Tissue Equivalent Proportional Counter (TEPC).

Microdosimetric spectra, kinetic energy spectra, and dose fragment contributions were calculated using Monte Carlo (GEANT IV) for monoenergetic and SOBP carbon beams of clinical energy. From microdosimetric spectra, lineal energy values …

Dissecting The Roles Of Human Smc Complexes In Transcription Regulation And Chromatin Organization, Ruoyu Wang

Dissertations and Theses (Open Access)

Metazoans utilize a constellation of distal regulatory elements to control gene transcription, and therefore they have to forge highly complex chromatin loops to spatially bridge these regulatory elements and genes in the three-dimensional (3D) genome. However, the hierarchy of chromatin contacts and their underlying mechanisms are not well-understood. SMC complexes including Cohesin complex and Condensin complex has been widely proposed to organize 3D genome structure, and further regulate metazoans’ gene transcription. Here, we aim to dissect the direct functions of SMC complexes (both Cohesin and Condensin) in transcriptional regulation and 3D genome organization, by utilizing an inducible protein degradation system. …

P53r245w Mutation Elicits Metastatic Phenotype In Pten Deficient Prostate Cancer, Ky Pham

Dissertations and Theses (Open Access)

Trp53 mutations are the most frequent genetic alterations in prostate cancer and are associated with more aggressive disease and worse overall survival. The majority of Trp53 mutations in prostate cancer are missense mutations, resulting in amino acid substitutions with profound effect. In addition to the loss of wild type function, missense mutations in Trp53 result in a gain-of-function (GOF) phenotype. This GOF phenotype confers biologic advantages to the tumor cells, enabling them to metastasize and invade distant organs. In this study, we generated mice carrying a conditional prostate-specific p53R245W mutant and Pten deletion to access the role of this common …

Fasting Reduces Intestinal Radiotoxicity Enabling Dose-Escalated Radiotherapy For Pancreatic Cancer, Marimar De La Cruz Bonilla

Dissertations and Theses (Open Access)

Surgical resection is the only potentially curative treatment for pancreatic cancer, but only 15-20% of patients have resectable tumors. In unresectable cases, stereotactic body radiotherapy (SBRT) may be used to give tumor-directed radiotherapy (RT). Unfortunately, this can cause severe gastrointestinal (GI) toxicity due to proximity of the pancreatic head to the duodenum. Protecting the intestine from the toxic side-effects of radiation may enable dose-escalation that could achieve more effective local control of disease. We and others have previously shown that a fast of 24 hours protects mice from lethal doses of the DNA-damaging agent etoposide. In this study, we demonstrate …

Investigating The Role Of Cd109 In Pancreatic Ductal Adenocarcinoma, Mennatallah Shaheen

Dissertations and Theses (Open Access)

Pancreatic Ductal Adenocarcinoma (PDAC) is the 3rd leading cause of cancer death in the US. We performed loss of function genomic screening on a cohort of four patient derived PDAC cell populations and our data shows a cell surface receptor CD109 to be a common vulnerability, the biologic role of which in PDAC is yet unstudied and largely unknown. We hypothesized that CD109 expression provides PDAC cells with a survival advantage, and promotes cancer progression through activation of downstream signaling. We believe therefore that targeting CD109 could improve PDAC patients’ survival. Here we report that CD109 plays a role in …

Gcn5 Loss Impacts Myc-Driven Cancer In Mice And Human Cells, Aimee Farria

Dissertations and Theses (Open Access)

GCN5 is the catalytic subunit in the acetyltransferase module of SAGA and ATAC, multiprotein complexes involved in the modification of histone and nonhistone proteins. GCN5 is most recognized as a co-activator of gene transcription. The SAGA complex is recruited to chromatin by transcription factors such as MYC and E2F1 where GCN5 acetylates H3K9 leading to a more open and accessible chromatin structure. Previous research has demonstrated that GCN5 also acetylates MYC, a protein that amplifies the expression of cancer-promoting genes and is frequently dysregulated in cancer, increasing its stability. Our lab has found there is a significant overlap in the …

Molecular Consequences Of High Taz Expression In Gliomas, Visweswaran Ravikumar

Dissertations and Theses (Open Access)

Diffuse high grade gliomas are complex and lethal neoplasms of the adult central nervous system that are driven by a range of genetic and epigenetic alterations. Molecular classification of these tumors has identified different transcriptional subtypes, the most notable being Proneural (PN) and Mesenchymal (MES) classes. The most aggressive forms of the disease have a Mesenchymal expression signature, with reported PN-to-MES transition occurring with tumor progression. Master regulatory analysis has identified the transcriptional co-activator TAZ (WWTR1) as a major driver of the MES transition. Overexpression of this single protein in glioma stem cells has been shown to drive a transition …

Preoccupation With Failure And Adherence To Shared Baselines: Measuring High-Reliability Organizational Culture, Jason M Etchegaray, Eric J Thomas, Jochen Profit

Faculty, Staff and Student Publications

OBJECTIVE: To create, administer, and psychometrically examine a survey to measure two new organizational culture factors - preoccupation with failure and adherence to shared baselines - in healthcare settings.

METHOD: Direct care providers (n = 4484) from a large healthcare system in the Southern United States completed a survey as part of their annual safety culture assessment.

RESULTS: We provide evidence about the internal consistency (Cronbach's alpha ranged from .80 to .89) factor structure, concurrent validity (correlation with overall patient safety grade ranged from .60 to .67, p

CONCLUSIONS: We established evidence for internal consistency and validity of two new …

The Society Of Abdominal Radiology At 10 Years: Reflections, Status Report, And Look To The Future, Manju Ambelil, David M Saulino, Atilla Ertan, Andrew W Dupont, Mamoun Younes

Faculty, Staff and Student Publications

CONTEXT.—: Recent studies examining immunohistochemical staining of colorectal biopsies for cytomegalovirus (CMV) reported that some cases showed only occasional small positive nuclei that were called equivocal for CMV.

OBJECTIVES.—: To determine the extent and clinical significance of equivocal CMV staining in colorectal biopsies.

DESIGN.—: Two-hundred twenty-one consecutive cases of colon and rectal biopsies that were stained for CMV by immunohistochemistry were retrieved from our files and reviewed. Staining results were recorded as negative, unequivocal, or equivocal. Results were correlated with clinicopathologic data, results of polymerase chain reaction studies for CMV, and treatment history.

RESULTS.—: Fifty-two cases (24% of all tested, …

Health Coaching To Encourage Obese Adults To Enroll In Commercially-Available Weight Management Programs: The Path To Health Study, Natalia I Heredia, Minjae Lee, Kevin O Hwang, Belinda M Reininger, Maria E Fernandez, Lorna H Mcneill

Faculty, Staff and Student Publications

Physicians are recommended to screen and refer obese patients to weight management programs (WMPs). There are often limited referral options for physicians, though commercially-available WMPs could be a potential solution. The purpose of this study (Path to Health) was to evaluate the efficacy of health coaching to promote enrollment in commercially-available WMPs through a two-arm, RCT with obese patients (n = 168) randomly assigned to intervention (n = 84) or control groups (n = 84). Intervention participants received phone health coaching to help them select and enroll in WMPs. We collected data on program enrollment, weight, self-reported physical activity (PA), …

Datagauge: A Practical Process For Systematically Designing And Implementing Quality Assessments Of Repurposed Clinical Data, Jose-Franck Diaz-Garelli, Elmer V Bernstam, Minjae Lee, Kevin O Hwang, Mohammad H Rahbar, Todd R Johnson

Faculty, Staff and Student Publications

The well-known hazards of repurposing data make Data Quality (DQ) assessment a vital step towards ensuring valid results regardless of analytical methods. However, there is no systematic process to implement DQ assessments for secondary uses of clinical data. This paper presents DataGauge, a systematic process for designing and implementing DQ assessments to evaluate repurposed data for a specific secondary use. DataGauge is composed of five steps: (1) Define information needs, (2) Develop a formal Data Needs Model (DNM), (3) Use the DNM and DQ theory to develop goal-specific DQ assessment requirements, (4) Extract DNM-specified data, and (5) Evaluate according to …

Pyroglutamic Acidemia: An Underrecognized And Underdiagnosed Cause Of High Anion Gap Metabolic Acidosis - A Case Report And Review Of Literature, Sidish S Venkataraman, Rachel Regone, Hussam M Ammar, Rukma R Govindu

Faculty, Staff and Student Publications

Pyroglutamic acidemia (oxoprolinemia) is an underrecognized cause of high anion gap acidosis resulting from derangement in the gamma-glutamyl cycle. Pyroglutamic acidemia is most commonly diagnosed in the pediatric population in patients with inherited autosomal recessive enzyme deficiencies. However, acquired pyroglutamic acidemia can present in the adult population. Patients often present with confusion, nausea, and vomiting as well as an elevated anion gap metabolic acidosis. This article describes a case of acquired pyroglutamic acidemia and emphasizes the need to consider this entity.

In Vitro Characterization Of Sonothrombolysis And Echocontrast Agents To Treat Ischemic Stroke, Himanshu Shekhar, Robert T Kleven, Tao Peng, Arunkumar Palaniappan, Kunal B Karani, Shaoling Huang, David D Mcpherson, Christy K Holland

Faculty, Staff and Student Publications

The development of adjuvant techniques to improve thrombolytic efficacy is important for advancing ischemic stroke therapy. We characterized octafluoropropane and recombinant tissue plasminogen activator (rt-PA)-loaded echogenic liposomes (OFP t-ELIP) using differential interference and fluorescence microscopy, attenuation spectroscopy, and electrozone sensing. The loading of rt-PA in OFP t-ELIP was assessed using spectrophotometry. Further, it was tested whether the agent shields rt-PA against degradation by plasminogen activator inhibitor-1 (PAI-1). An in vitro system was used to assess whether ultrasound (US) combined with either Definity or OFP t-ELIP enhances rt-PA thrombolysis. Human whole blood clots were mounted in a flow system and visualized …

Ms 184 Guide To Carlos Vallbona, Md Papers (1968-2014), Carlos Vallbona (1927-2015)

Manuscript Finding Aids

The Carlos Vallbona, MD papers contains correspondence, course materials, slides; files from his 3701 Kirby office; and other material detailing the career of Dr. Vallbona as a pediatrician, educator, advocate, physical therapy and post-polio syndrome specialist. He held positions at Baylor College of Medicine and TIRR. The materials date from between 1968 and 2014. See more at MS 184.

Endosomal Trafficking And Exosomal Secretion Of Egfrviii, Kimiya Memarzadeh

Dissertations and Theses (Open Access)

The epidermal growth factor receptor (EGFR) variant three (EGFRvIII) mutation is linked with approximately one third of Glioblastoma Multiforme (GBM) tumors and is associated with poor patient prognosis. Persistent signaling due to a lack of the EGFR ectodomain and inefficient degradation have been suggested to underlie the tumorgenic properties of EGFRvIII. I observed that, like the parental EGFR, EGFRvIII is internalized into the intraluminal vesicles of late endosomes / multivesicular bodies (MVBs) but does not follow the canonical pathway by which wild-type EGFR is degraded following MVB fusion with lysosomes. I determined that EGFRvIII is secreted on exosomes, the intraluminal …

Microrna-374a, -4680, And -133b Suppress Cell Proliferation Through The Regulation Of Genes Associated With Human Cleft Palate In Cultured Human Palate Cells, Akiko Suzuki, Aimin Li, Mona Gajera, Nada Abdallah, Musi Zhang, Zhongming Zhao, Junichi Iwata

Faculty, Staff and Student Publications

BACKGROUND: Cleft palate (CP) is the second most common congenital birth defect; however, the relationship between CP-associated genes and epigenetic regulation remains largely unknown. In this study, we investigated the contribution of microRNAs (miRNAs) to cell proliferation and regulation of genes involved in CP development.

METHODS: In order to identify all genes for which mutations or association/linkage have been found in individuals with CP, we conducted a systematic literature search, followed by bioinformatics analyses for these genes. We validated the bioinformatics results experimentally by conducting cell proliferation assays and miRNA-gene regulatory analyses in cultured human palatal mesenchymal cells treated with …

The Influence Of Vitamin D Supplementation On Local And Systemic Inflammatory Markers In Periodontitis Patients: A Pilot Study, Mohamed M Meghil, Lance Hutchens, Anas Raed, Neha A Multani, Mythilypriya Rajendran, Haidong Zhu, Stephen Looney, Mahmoud Elashiry, Roger M Arce, Mark E Peacock, Yanbin Dong, Christopher W Cutler

Faculty, Staff and Student Publications

OBJECTIVES: Vitamin D deficiency/insufficiency is a worldwide public health issue that has been linked to numerous inflammatory disorders, including periodontitis. There is increasing support for a role for adequate vitamin D levels in overall health. Populations with darker skin color have a higher prevalence of vitamin D deficiency/insufficiency and periodontitis. The purpose of this small pilot study was to investigate the influence of 12 weeks of 25(OH)D vitamin D supplementation (VDS) on mediators of systemic inflammation in dark-skinned, periodontitis patients.

MATERIALS AND METHODS: A total of 23 patients with moderate to severe periodontitis were randomly assigned to the vitamin D …

Autonomic Response In Autism Spectrum Disorder: Relationship To Social And Cognitive Functioning, Michelle A Patriquin, Elizabeth M Hartwig, Bruce H Friedman, Stephen W Porges, Angela Scarpa

Staff and Researcher Publications

Individuals with autism spectrum disorder (ASD) may exhibit chronic autonomic nervous system (ANS) hyperarousal (e.g., lower respiratory sinus arrhythmia and higher heart rate) compared to their typically developing peers, reflecting a chronic biological threat response. The sustained nature of this cardiac threat suggests tonic nervous system perception of threat in safe contexts. Herein, the cardiac literature in adult and child populations with ASD is reviewed and placed within a continuum of functioning in order to inform the relationship between cardiac response and functioning in ASD. Findings from this review support the relationship between chronic autonomic hyperarousal and emotional and behavioral …

Ms 204 Guide To Sara Ann Barton's Lithium And Trace Metal Research Papers (Created April 4 - November 8, 2015), Sarah Ann Barton

Manuscript Finding Aids

The Sara Ann Barton's Lithium and Trace Metal research papers includes research material, reprints, environmental reports, questionnaires, and notes from Barton’s research on lithium and trace metals. Some material is in Spanish. See more at MS 204.

Integrating Diverse Disciplines To Enhance Interprofessional Competency In Healthcare Delivery, Tiffany Champagne-Langabeer, Lee Revere, Mariya Tankimovich, Erica Yu, Robert Spears, Jennifer Lee Swails

Faculty, Staff and Student Publications

Interprofessional education (IPE) typically involves clinical simulation exercises with students from medical and nursing schools. Yet, healthcare requires patient-centered teams that include diverse disciplines. Students from public health and informatics are rarely incorporated into IPE, signaling a gap in current educational practices. In this study, we integrated students from administrative and non-clinical disciplines into traditional clinical simulations and measured the effect on communication and teamwork. From July 2017-July 2018, 408 students from five schools (medicine, nursing, dentistry, public health, and informatics) participated in one of eight three-hour IPE clinical simulations with Standardized Patients and electronic health record technologies. Data were …

An Examination Of Student Performance In Pre-Requisite Coursework And Upper Division Nursing Coursework, Jennifer L. Brown, Cheryl M. Smith

Journal of Nursing & Interprofessional Leadership in Quality & Safety

Admission and retention of qualified nursing students are essential in meeting the demands of a rapidly changing health care environment and nursing shortage. The purpose of this exploratory correlational study was to determine the relationship between student performance in quantitative pre-requisite coursework and student performance in upper division nursing coursework in order to identify students at-risk for attrition. A series of descriptive and correlational analyses were conducted using pre-existing institutional data. A moderate relationship existed among the chemistry II and first-year upper division nursing courses (r = .21 to r = .40). These results suggest that prerequisite chemistry course …

Aminophylline Shortage And Current Recommendations For Reversal Of Vasodilator Stress: An Asnc Information Statement Endorsed By Scmr, Aiden Abidov, Vasken Dilsizian, Rami Doukky, W Lane Duvall, Christopher Dyke, Michael D Elliott, Fadi G Hage, Milena J Henzlova, Nils P Johnson, Ronald G Schwartz, Gregory S Thomas, Andrew J Einstein

Faculty, Staff and Student Publications

Pharmacologic reversal of serious or intolerable side effects (SISEs) from vasodilator stress is an important safety and comfort measure for patients experiencing such effects. While typically performed using intravenous aminophylline, recurrent shortages of this agent have led to a greater need to limit its use and consider alternative agents. This information statement provides background and recommendations addressing indications for vasodilator reversal, timing of a reversal agent, incidence of observed SISE with vasodilator stress, clinical and logistical considerations for aminophylline-based reversal, and alternative non-aminophylline based reversal protocols.