Peter N Tadros

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Electrical uncoupling at gap junctions during acute myocardial ischemia contributes to conduction abnormalities and reentrant arrhythmias. Increased levels of intracellular Ca(2+) and H(+) and accumulation of amphipathic lipid metabolites during ischemia promote uncoupling, but other mechanisms may play a role. We tested the hypothesis that uncoupling(More)
BACKGROUND We compared transcatheter aortic-valve replacement (TAVR), using a self-expanding transcatheter aortic-valve bioprosthesis, with surgical aortic-valve replacement in patients with severe aortic stenosis and an increased risk of death during surgery. METHODS We recruited patients with severe aortic stenosis who were at increased surgical risk as(More)
Intercellular communication may be modulated by the rather rapid turnover and degradation of gap junction proteins, since many connexins have half-lives of 1-3 h. While several morphological studies have suggested that gap junction degradation occurs after endocytosis, our recent biochemical studies have demonstrated involvement of the ubiquitin-proteasome(More)
BACKGROUND The U.S. pivotal trial for the self-expanding valve found that among patients with severe aortic stenosis at increased risk for surgery, the 1-year survival rate was 4.9 percentage points higher in patients treated with a self-expanding transcatheter aortic valve bioprosthesis than in those treated with a surgical bioprosthesis. OBJECTIVES(More)
OBJECTIVE The present studies were performed to examine the degradation of connexin43-containing gap junctions by the lysosome or the proteasome in normal and heat-stressed cultures of neonatal rat ventricular myocytes. METHODS Primary cultures were prepared from neonatal rat ventricular myocytes. Connexin43 was detected by immunoblotting,(More)
BACKGROUND In patients with severe aortic stenosis at increased risk for surgery, self-expanding transcatheter aortic valve replacement (TAVR) is associated with improved 2-year survival compared with surgery. OBJECTIVES This study sought to determine whether this clinical benefit was sustained over time. METHODS Patients with severe aortic stenosis(More)
OBJECTIVE Our purpose was to determine whether myometrial cell lines and rat myometrial tissue contained additional gap junction proteins besides connexin43. STUDY DESIGNS Syrian hamster myocytes (SHM-ER) and human SK-UT-1 myometrial cell lines were analyzed for intercellular coupling by microinjection of Lucifer yellow. These cell lines and myometrial(More)
A family of related connexin genes encodes the subunit gap junction proteins that form intercellular channels in different tissues. Connexin40 (Cx40) is one of these proteins, and it exhibits limited expression only in a few cells of the cardiovascular system. To begin to analyze Cx40 expression, we isolated a 3.3-kb rat Cx40 cDNA by hybridization screening(More)
INTRODUCTION Patients with end-stage liver disease (ESLD) awaiting transplant are at increased risk of bleeding. Nevertheless, these patients routinely undergo cardiac catheterization for various indications. Safety and outcomes of cardiac catheterization in these patients are not well reported. METHODS In a case-control study 43 patients with ESLD who(More)
Patients with heart failure have reduced forearm vasodilator responses when endothelial cell nitric oxide production is stimulated by muscarinic agonists. The aim of this study was to determine if activity of the nitric oxide pathway was also abnormal under basal conditions. Forearm blood flow (FBF) was measured with strain-gauge plethysmography in response(More)