Leukocyte recruitment and expression of chemokines following different forms of vascular injury.

Unlabelled: Inflammation plays a central role in restenosis following coronary intervention. Recent human and animal data suggest important differences between the inflammatory responses to simple balloon angioplasty compared with stent implantation. To investigate the mechanisms of these differences, New Zealand white rabbits underwent bilateral iliac artery balloon denudation.

Low-risk percutaneous coronary interventions without on-site cardiac surgery: two years' observational experience and follow-up.

Background: We studied the safety and efficacy of performing low-risk elective and acute infarct percutaneous coronary interventions at a community hospital without cardiac surgical capability.

Methods: Immanuel St Joseph's Hospital is located 85 miles from St Mary's Hospital, which is the nearest center with on-site cardiac surgery. All components of the Mayo Clinic percutaneous coronary intervention program were replicated at Immanuel St Joseph's Hospital, including a telemedicine system to enable real-time consultation with interventional and cardiac surgical colleagues during procedures.

Design-Dependent Variations in Coronary Stent Stenosis Measured as Precisely by Angiography as by Histology.

BACKGROUND: Coronary stent restenosis is a growing clinical concern which, because restenosis may vary with stent design, requires a validated, accurate and sensitive method of evaluation as new stents are developed. Histologic analysis of arterial cross sections, a highly accurate tool in animal models, has limited applicability in humans. Quantitative coronary angiography, while commonly used in the clinical evaluation of coronary interventions, has a controversial role as an adequate measure of restenosis, and few studies have validated quantitative angiography in diseased arteries.

Design-Dependent Variations in Coronary Stent Stenosis Measured as Precisely by Angiography as by Histology.

BACKGROUND: Coronary stent restenosis is a growing clinical concern which, because restenosis may vary with stent design, requires a validated, accurate, and sensitive method of evaluation as new stents are developed. Histologic analysis of arterial cross sections, a highly accurate tool in animal models, has limited applicability in humans. Quantitative coronary angiography, while commonly used in the clinical evaluation of coronary interventions, has a controversial role as an adequate measure of restenosis, and few studies have validated quantitative angiography in diseased arteries.

Constitutive activation of the alpha 1B-adrenergic receptor by all amino acid substitutions at a single site. Evidence for a region which constrains receptor activation.

Mutations in an intracellular region of the alpha 1B-adrenergic receptor constitutively activate the receptor, resulting in G protein coupling in the absence of agonist, as evidenced by elevated levels of polyphosphoinositide hydrolysis. Remarkably, all 19 possible amino acid substitutions at a single site in this region (alanine 293) confer constitutive activity. This set of mutated receptors exhibits a graded range of elevated biological activities, apparently representing a spectrum of receptor conformations which mimic the "active" state of the wild type receptor.

Discrete amino acid sequences of the alpha 1-adrenergic receptor determine the selectivity of coupling to phosphatidylinositol hydrolysis.

We have constructed a variety of chimeric beta 2/alpha 1 adrenergic receptors (AR) in which selected portions of the third intracellular loop of the alpha (1B)AR were substituted into the corresponding regions of the beta 2AR. The mutant receptors were both transiently and permanently expressed in COS-7 or L-cells, respectively, and tested for their ability to mediate epinephrine-induced activation of polyphosphoinositide (PI) hydrolysis and adenylylcyclase. We have determined that 27 amino acids of the alpha (1B)AR (residues 233-259) derived from the N-terminal portion of the third intracellular loop represent the structural determinant conferring to the beta 2AR the ability to activate PI hydrolysis.