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Quantitative Analysis And Imaging-Based Insights Into The Characteristics And Mechanisms Of Yeast Pattern Formation, Lin Chen

Dissertations and Theses (Open Access)

Biofilm formation is a common lifestyle adapted by bacteria and fungi in response to various environmental stresses. Bacterial and fungal biofilms adhering to medical devices convey resistance to antibiotics or biocides, causing high rates of clinical infections. Microorganisms are protected from harsh environmental conditions by reduced stress penetration through the complex biofilm architecture with distinct patterns. Although the molecular regulations of surface patterning have been well characterized in bacteria, the mechanisms underlying the complex pattern formation in eukaryotic biofilms remain unclear.

This dissertation aims to investigate the salient features of robust colony expansion in yeast biofilms and the processes driving …

Brachiocephalic Artery Cannulation In Proximal Aortic Surgery That Requires Circulatory Arrest, Mehmet Unal, Oguz Yilmaz, Ilker Akar, Ilker Ince, Cemal Aslan, Fatih Koc, Haluk Kafali

The Texas Heart Institute Journal

The brachiocephalic artery is an alternative cannulation site in the repair of ascending aortic lesions that require circulatory arrest. We evaluate the effectiveness and safety of this technique.

Proximal aortic surgery was performed in 32 patients from 2006 through 2012 via brachiocephalic artery cannulation and circulatory arrest. Twenty-four (75%) of the patients were men. The mean age was 48.69 ± 9.43 years (range, 30–68 yr). Twelve had type I dissection, 2 had type II dissection, and 18 had true aneurysms of the ascending aorta. All operations were performed through a median sternotomy. The arterial cannula was inserted through an 8-mm …

Repeated Transradial Catheterization: Feasibility, Efficacy, And Safety, Marinos A Charalambous, Savvas S Constantinides, Michael A Talias, Elpidoforos S Soteriades, Christos P Christou

The Texas Heart Institute Journal

Transradial access is an alternative to the transfemoral approach in coronary interventions. It results in less access-site bleeding, shorter hospital stays, lower costs, and less pain for the patient. However, some authors have suggested that the transradial approach might lead to radial artery occlusion, which precludes repeated same-artery catheterizations. Using data from our center, we evaluated the feasibility, safety, and efficacy of repeated transradial catheterization.

We reviewed the 3,006 transradial catheterizations performed at our center from 2006 through 2009. Patients who had undergone at least one repeated transradial catheterization were identified, their cases monitored through 2012, and their baseline characteristics …

Anticoagulation With Bivalirudin During Deep Hypothermic Circulatory Arrest In A Patient With Heparin-Induced Thrombocytopenia, Agamemnon Pericleous, Mostafa Sadek, Mary Fitzmaurice, Constance Caldwell, Kris Natividad, Konstadinos A Plestis

The Texas Heart Institute Journal

Heparin-induced thrombocytopenia is a well-recognized complication of anticoagulation with heparin. We present the case of a patient with recent heparin-induced thrombocytopenia who subsequently needed surgery on an emergency basis for acute type A aortic dissection. This article reports the successful use of bivalirudin, a direct thrombin inhibitor, as an alternative to heparin throughout cardiopulmonary bypass and deep hypothermic circulatory arrest. We contend that bivalirudin is a safe alternative to heparin when performing surgery for aortic dissection and should be considered as an option for use in patients who present with heparin-induced thrombocytopenia.

Aortic Valve Reconstruction With Use Of Pericardial Leaflets In Adults With Bicuspid Aortic Valve Disease: Early And Midterm Outcomes, Meong Gun Song, Hyun Suk Yang, Jong Bum Choi, Je Kyoun Shin, Hyun Keun Chee, Jun Seok Kim

The Texas Heart Institute Journal

In this study, we retrospectively analyzed the outcomes of adults with bicuspid aortic valve (BAV) disease who underwent aortic valve reconstructive surgery (AVRS), consisting of replacement of the diseased BAV with 2 or 3 pericardial leaflets plus fixation of the sinotubular junction for accurate and constant leaflet coaptation. From December 2007 through April 2013, 135 consecutive patients (mean age, 49.2 ± 13.1 yr; 73.3% men) with symptomatic BAV disease underwent AVRS. Raphe was observed in 84 patients (62.2%), and the remaining 51 patients had pure BAV without raphe. A total of 122 patients (90.4%) underwent 3-leaflet reconstruction, and 13 (9.6%) …

Percutaneous Repair Of Post-Myocardial Infarction Ventricular Septal Defect: Current Approaches And Future Perspectives, Maria D Baldasare, Mark Polyakov, Glenn W Laub, Joseph T Costic, Daniel J Mccormick, Sheldon Goldberg

The Texas Heart Institute Journal

Post-myocardial infarction ventricular septal defect is a devastating complication of ST-elevation myocardial infarction. Although surgical intervention is considered the gold standard for treatment, it carries high morbidity and mortality rates. We present 2 cases that illustrate the application of percutaneous closure of a post-myocardial infarction ventricular septal defect: the first in a patient who had undergone prior surgical closure and then developed a new shunt, and the second as a bridge to definitive surgery in a critically ill patient.

Large-Scale Identification Of Chemically Induced Mutations In Drosophila Melanogaster, Nele A Haelterman, Lichun Jiang, Yumei Li, Vafa Bayat, Hector Sandoval, Berrak Ugur, Kai Li Tan, Ke Zhang, Danqing Bei, Bo Xiong, Wu-Lin Charng, Theodore Busby, Adeel Jawaid, Gabriela David, Manish Jaiswal, Koen J T Venken, Shinya Yamamoto, Rui Chen, Hugo J Bellen

Faculty, Staff and Students Publications

Forward genetic screens using chemical mutagens have been successful in defining the function of thousands of genes in eukaryotic model organisms. The main drawback of this strategy is the time-consuming identification of the molecular lesions causative of the phenotypes of interest. With whole-genome sequencing (WGS), it is now possible to sequence hundreds of strains, but determining which mutations are causative among thousands of polymorphisms remains challenging. We have sequenced 394 mutant strains, generated in a chemical mutagenesis screen, for essential genes on the Drosophila X chromosome and describe strategies to reduce the number of candidate mutations from an average of …

Off-Pump Myocardial Revascularization In A High-Risk Patient With Essential Thrombocythemia, Ahmad K Darwazah, Hamad Madi, Rami Zagha, Yahia Hawash

The Texas Heart Institute Journal

Essential thrombocythemia is a rare type of myeloproliferative disorder. Cerebral, myocardial, and peripheral thrombosis are all frequent complications of the disease.

A 71-year-old man presented with severe coronary artery disease, associated with cerebral vascular ischemic changes and erythromelalgia. His platelet count was 1,486 ×103/μL. The patient underwent successful myocardial revascularization by means of an off-pump technique after his platelet count had been reduced by hydroxycarbamide administration.

We conclude that the use of off-pump cardiopulmonary bypass in high-risk patients with essential thrombocythemia is safe. Reducing platelet count via the administration of hydroxycarbamide and the careful balancing of antiplatelets and anticoagulants is …

Effect Of Electrocautery On Endothelial Integrity Of The Internal Thoracic Artery: Ultrastructural Analysis With Transmission Electron Microscopy, Burak Onan, Mehmet Yeniterzi, Ismihan Selen Onan, Burak Ersoy, Suheyla Gonca, Elif Gelenli, Seyhun Solakoglu, Ihsan Bakir

The Texas Heart Institute Journal

The internal thoracic artery (ITA) is typically harvested from the chest wall by means of conventional electrocautery. We investigated the effects of electrocautery on endothelial-cell and vessel-wall morphology at the ultrastructural level during ITA harvesting. Internal thoracic artery specimens from 20 patients who underwent elective coronary artery bypass grafting were investigated in 2 groups. The ITA grafts were sharply dissected with use of a scalpel and clips in the control group (n=10) and were harvested by means of electrocautery in the study group (n=10). Each sample was evaluated for intimal, elastic-tissue, muscular-layer, and adventitial changes. Free flow was measured intraoperatively. …

Contemporary Use Of Balloon Aortic Valvuloplasty In The Era Of Transcatheter Aortic Valve Implantation, Dawn S Hui, David M Shavelle, Mark J Cunningham, Ray V Matthews, Vaughn A Starnes

The Texas Heart Institute Journal

The development of transcatheter aortic valve implantation (TAVI) has increased the use of balloon aortic valvuloplasty (BAV) in treating aortic stenosis. We evaluated our use of BAV in an academic tertiary referral center with a developing TAVI program.

We reviewed 69 consecutive stand-alone BAV procedures that were performed in 62 patients (mean age, 77 ± 10 yr; 62% men; baseline mean New York Heart Association functional class, 3 ± 1) from January 2009 through December 2012. Enrollment for the CoreValve® clinical trial began in January 2011. We divided the study cohort into 2 distinct periods, defined as pre-TAVI (2009–2010) and …

Use Of A Melody Pulmonary Valve In Transcatheter Valve-In-Valve Replacement For Tricuspid Valve Bioprosthesis Degeneration, David M Filsoof, David F Snipelisky, Brian P Shapiro

The Texas Heart Institute Journal

Bioprosthetic heart valves can degenerate and fail over time. Repeat surgery as a means of replacement increases morbidity and mortality rates, and some patients are not candidates for reoperation. A newer treatment, percutaneous transcatheter valve-in-valve implantation, might delay or substitute for invasive procedures. We present the case of a 51-year-old woman, a poor candidate for surgery who had prosthetic tricuspid valve degeneration and stenosis. We successfully performed valve-in-valve placement of a Melody® valve, using a procedure originally intended to treat pulmonary valve conduit obstruction or regurgitation. To our knowledge, this is among the first case reports to describe the use …

First Carpometacarpal Arthroplasty With Ligamentous Reconstruction: A Long-Term Follow-Up, Mark A Yaffe, Bennet Butler, James M Saucedo, Daniel J Nagle

Faculty, Staff and Student Publications

BACKGROUND: The purpose of the present study is to evaluate a single surgeon's short, intermediate, and long-term clinical, functional, and radiographic outcomes with a trapeziectomy with flexor carpi radialis (FCR) suspension arthroplasty without tendon interposition (LRSA).

METHODS: Twenty-one patients underwent 26 FCR suspension arthroplasties without tendon interposition by a single senior surgeon. All patients had Eaton stage III and IV carpometacarpal (CMC) osteoarthritis. The Patient-Rated Wrist and Hand Evaluation (PRWHE) and Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH) were used to evaluate functional outcomes. A comprehensive strength and range of motion evaluation was performed to evaluate clinical outcomes. Plain …

Inflammation And C-Reactive Protein In Atrial Fibrillation: Cause Or Effect?, Roberto Galea, Maria Teresa Cardillo, Annalisa Caroli, Maria Giulia Marini, Chiara Sonnino, Maria L Narducci, Luigi M Biasucci

The Texas Heart Institute Journal

Atrial fibrillation is associated with substantial morbidity and mortality rates. The incompletely understood pathogenesis of this cardiac dysrhythmia makes it difficult to improve approaches to primary and secondary prevention. Evidence has accumulated in regard to a relationship between inflammation and atrial fibrillation. Investigators have correlated the dysrhythmia with myocarditis, pericardiotomy, and C-reactive protein levels, suggesting that inflammation causes atrial fibrillation or participates in its onset and continuation. Conversely, other investigators suggest that atrial fibrillation induces an inflammatory response. In this review, we summarize and critically discuss the nature and clinical role of inflammation and C-reactive protein in atrial fibrillation.

Association Of Cardiorespiratory Fitness And Adiposity With Inflammatory Biomarkers In Young Adults, Eunduck Park

Dissertations and Theses (Open Access)

Background: Low grade systemic inflammation plays a key role in atherosclerosis, and C-reactive protein (hs-CRP), interleukin-6 (IL-6), and tumor necrosis factor- alpha (TNF -a), markers of systemic inflammation, are associated with cardiovascular events and adiposity. Cardiorespiratory fitness has shown health benefits by reducing circulating levels of inflammatory markers. However, it remains uncertain whether the negative association between cardiorespiratory fitness and inflammatory biomarkers is due to cardiorespiratory fitness itself or results from lower levels of adiposity. Moreover, the evidence examining the interaction between cardiorespiratory fitness and adiposity in inflammation in young adults is lacking.

Purpose: The aims of this study were …

Mapping The Human Vasculature By In Vivo Phage Display, Julianna Bronk

Dissertations and Theses (Open Access)

In vivo phage display screenings by intravenous injection of a random phage-displayed peptide library allow for the selection of peptides that localize to specific vascular beds. At the University of Texas MD Anderson Cancer Center, we have had the opportunity to perform phage display screenings in cancer patients in order to select for cancer specific targets directly in humans. These targets serve to define biochemical diversity of endothelial cell surfaces and can be validated and explored towards the design of vascular-targeted pharmacology. In the most recent patient screen, samples were recovered from hepatocellular carcinoma (HCC) as well as 26 additional …

Nontyphoidal Cardiac Salmonellosis: Two Case Reports And A Review Of The Literature, Daniel Ortiz, Eric M Siegal, Christopher Kramer, Bijoy K Khandheria, Ernesto Brauer

The Texas Heart Institute Journal

Nontyphoidal Salmonella, especially Salmonella enterica, is a rare cause of endocarditis and pericarditis that carries a high mortality rate. Proposed predisposing conditions include immunodeficiency states, congenital heart defects, and cardiac valve diseases. We present 2 cases of cardiovascular salmonellosis. The first case is that of a 73-year-old woman with mechanical mitral and bioprosthetic aortic valves who died from sequelae of nontyphoidal Salmonella mitral valve vegetation, aortic valve abscess, and sepsis. The second case is that of a 62-year-old man with a recent systemic lupus erythematosus exacerbation treated with oral steroids, who presented with obstructive features of tamponade and sepsis secondary …

Abdominal Fat Suspension Device For Maintaining Normal Cardiorespiratory Function In Patients Undergoing Conscious Sedation During Surgery: A Feasibility Study, Norman F Truong, Joanna C Nathan, Daeun Yoon, Gabriel Ochoa, Marisa Prevost, Sehyun Yun, Z Maria Oden, Mehdi Razavi

The Texas Heart Institute Journal

Obese patients undergoing conscious-sedation surgery have increased perioperative morbidity because their excess abdominal tissue limits diaphragmatic excursion. We describe a simple device that might help attenuate this risk. We created a noninvasive suction device for abdominal suspension. By lifting the burden of excess weight, this device should decrease respiratory effort. To test the feasibility of excess weight removal in relieving cardiac stress, we tested 22 supine, healthy, normal-weight subjects by measuring their heart rates with and without a 13-kg tissue model on their abdomen to simulate excess weight. There was no significant difference in blood oxygen saturation before and after …

Potential Roles Of Peroxidases In Caenorhabditis Elegans Innate Immunity, George R. Tiller, George R. Tiller

Dissertations and Theses (Open Access)

The production of ROS (reactive oxygen species) in response to pathogen detection is a rapid, nonspecific response that is evolutionarily conserved from nematodes to humans. ROS serve as direct and indirect effectors of innate and adaptive immunity. In Caenorhabditis elegans, a ROS burst is observed during infection and is mediated by the dual oxidase BLI-3, which produces H₂O₂. RNAi (RNA interference) to reduce the amount of BLI-3 results in a significant increase in susceptibility to pathogens, suggesting BLI-3 has a role in the immune response. However, H₂O₂ by itself is not a …

Angiomotin Is A Novel Cadherin-11 Interacting Protein That Mediates Migration In Prostate Cancer Cells, Angelica Ortiz

Dissertations and Theses (Open Access)

Prostate cancer (PCa), the second leading cause of cancer-related deaths among men in the United States, has the proclivity to metastasize to bone resulting in sclerotic lesions. These cancer induced bone growths cause bone pain and fractures. Therefore, understanding the molecular mechanisms contributing to PCa bone metastasis is required in order to find better prognostic tools and suitable targets for metastasis treatment and/ or prevention. Previous work in our laboratory showed increased expression of cadherin-11 (Cad11), a mesenchymal cadherin, during PCa progression. Furthermore, Cad11 expression endows PCa cells with increased migratory potential and metastasis to bone. Deletion of the Cad11 …

Genomic Characterization Of Polyps In Familial Adenomatous Polyposis Patients And Identification Of Candidate Chemopreventive Drugs, Francis A. San Lucas

Dissertations and Theses (Open Access)

Familial adenomatous polyposis (FAP) is an autosomal dominant disease characterized by APC germline mutations and the development of hundreds to thousands of premalignant adenomas in the gastrointestinal tract at a young age. If left untreated, these patients inevitably develop colon cancer (CRC) and small bowel tumors. We performed exome sequencing of samples from 12 FAP patients to characterize adenomas and to identify candidate genes of adenoma development that may serve as potential targets for chemoprevention drug development. From each patient, a blood and at least one polyp were sequenced with a total of 25 polyps analyzed. In some cases, normal …

Use Of Oversized Injectable Valves In Growing Children For Total Repair Of Right Ventricular Outflow Tract Anomalies (Preliminary Results), Luca Deorsola, Pietro Angelo Abbruzzese

The Texas Heart Institute Journal

Right ventricular outflow tract surgery was originally confined to transannular patching, in the belief that pulmonary regurgitation was well tolerated. Because follow-up evaluations revealed the deleterious effects of pulmonary regurgitation, surgery today aims to spare or replace the valve. Available replacement devices have short lifetimes, considering growth mismatch in children. We hypothesize that oversizing the right infundibulum anticipates growth and that a squeezed prosthesis can complete the expansion process.

The No-React® Injectable BioPulmonic Valve is designed for right infundibular surgery in adults, and hundreds of implants have shown promising results. We used this device for surgery in babies, with the …

The In-Hospital Consultation Today: Whom Does It Best Serve?, Herbert L Fred

The Texas Heart Institute Journal

No abstract provided.

Right Ventricular Outflow Tract Obstruction Caused By Double-Chambered Right Ventricle Presenting In Adulthood, John Kokotsakis, Efthymia G Rouska, Leanne Harling, Hutan Ashrafian, Vania Anagnostakou, Christos Charitos, Thanos Athanasiou

The Texas Heart Institute Journal

Congenital heart diseases that cause obstruction of the right ventricular outflow tract are often difficult to diagnose. We report the case of a 49-year-old man who presented with long-standing shortness of breath on exertion. Imaging revealed right ventricular outflow tract obstruction caused by a double-chambered right ventricle, and he was referred for surgical correction. This case emphasizes both the detailed perioperative evaluation that is needed when diagnosing adults who present with manifestations of congenital heart disease and a method of successful surgical correction that resulted in symptom resolution.

Global Burden Of Disease Study 2010: Interpretation And Implications For The Neglected Tropical Diseases, Peter J. Hotez, Miriam Alvarado, Maria Gloria Basanez, Ian Bolliger, Et Al.

Faculty, Staff and Students Publications

No abstract provided.

Integrating Domain Knowledge To Improve Signal Detection From Electronic Health Records For Pharmacovigilance, Ning Shang

Dissertations and Theses (Open Access)

The intent of this dissertation is to make a contribution to the field of pharmacovigilance. Pharmacovigilance, also known as post-marketing drug surveillance, is the process of continued monitoring for adverse drug reactions (ADRs) after drugs are released into the market. An ADR is a harmful or unpleasant reaction related to the use of a medical product. ADRs were reported to be between the fourth and sixth leading cause of death in the United States in 1994, accounting for 3-7% of medical hospital admissions. On account of the practice of pharmacovigilance, Vioxx (Rofecoxib) and Avandia (Rosiglitazone) are examples of high profile …

Ic 003 Gude To Houston Academy Of Medicine Records, 1936-1988, Houston Academy Of Medicine

Institutional Finding Aids

Houston Academy of Medicine records consists of about 18 boxes and contains reports, financial and legal documents, correspondence, and printed material that document the history of the Houston Academy of Medicine. See more at IC 003.

Pattern Of Mutation Rates In The Germline Of Drosophila Melanogaster Males From A Large-Scale Mutation Screening Experiment, Jian-Jun Gao, Xue-Rong Pan, Jing Hu, Li Ma, Jian-Min Wu, Ye-Lin Shao, Shi-Meng Ai, Shu-Qun Liu, Sara A Barton, Ronny C Woodruff, Ya-Ping Zhang, Yun-Xin Fu

Faculty, Staff and Student Publications

The sperm or eggs of sexual organisms go through a series of cell divisions from the fertilized egg; mutations can occur at each division. Mutations in the lineage of cells leading to the sperm or eggs are of particular importance because many such mutations may be shared by somatic tissues and also may be inherited, thus having a lasting consequence. For decades, little has been known about the pattern of the mutation rates along the germline development. Recently it was shown from a small portion of data that resulted from a large-scale mutation screening experiment that the rates of recessive …

Exertional Dyspnea As A Symptom Of Infrarenal Aortic Occlusive Disease, Stacey L Schott, Fernanda Porto Carreiro, James R Harkness, Mahmoud B Malas, Stephen M Sozio, Sammy Zakaria

The Texas Heart Institute Journal

Advanced atherosclerosis of the aorta can cause severe ischemia in the kidneys, refractory hypertension, and claudication. However, no previous reports have clearly associated infrarenal aortic stenosis with shortness of breath. A 77-year-old woman with hypertension and hyperlipidemia presented with exertional dyspnea. Despite extensive testing and observation, no apparent cause for this patient's dyspnea was found. Images revealed severe infrarenal aortic stenosis. After the patient underwent stenting of the aortic occlusion, she had immediate symptomatic improvement and complete resolution of her dyspnea within one month. Twelve months after vascular intervention, the patient remained asymptomatic. In view of the distinct and lasting …

Natural Progression Of Low-Gradient Severe Aortic Stenosis With Preserved Ejection Fraction, Antony Leslie Innasimuthu, Sanjay Kumar, Jason Lazar, William E Katz

The Texas Heart Institute Journal

Because the natural progression of low-gradient aortic stenosis (LGAS) has not been well defined, we performed a retrospective study of 116 consecutive patients with aortic stenosis who had undergone follow-up echocardiography at a median interval of 698 days (range, 371–1,020 d). All patients had preserved left ventricular ejection fraction (>0.50) during and after follow-up.

At baseline, patients were classified by aortic valve area (AVA) as having mild stenosis (≥1.5 cm2), moderate stenosis (≥1 to <1.5 cm2), or severe stenosis (<1 cm2). Severe aortic stenosis was further classified by mean gradient (LGAS, mean <40 mmHg; high-gradient aortic stenosis [HGAS], mean ≥40 mmHg). We compared baseline and follow-up values among 4 groups: patients with mild stenosis, moderate stenosis, LGAS, and HGAS.

At baseline, 30 patients had mild stenosis, 54 had moderate stenosis, 24 had LGAS, and 8 had HGAS. Compared with the moderate group, the LGAS …

Spontaneous Coronary Artery Dissection (Scad): New Insights Into This Not-So-Rare Condition, Sharonne N Hayes

The Texas Heart Institute Journal

No abstract provided.