No effect of clopidogrel activity or cessation on vascular function or markers of inflammation.

The platelet adenosine diphosphate (ADP)-receptor blocker clopidogrel is effective in reducing the rate of thrombosis in cardiovascular disease, but may also have nonplatelet activity. However, there is variability in the suppression of platelet function in individuals, leading to the concept of clopidogrel resistance, that is, reduced platelet-suppressing activity. We tested the hypothesis that some of the beneficial effect of clopidogrel may be due to the variable activity of this drug on the vascular system (assessed by plasma markers von Willebrand factor and soluble E-selectin, and functional arterial pulse wave velocity) and inflammation (C-reactive protein and interleukin-6) while 32 patients with coronary artery disease taking 75 mg clopidogrel daily, and again 2 weeks after cessation of clopidogrel therapy.

Ethnic/racial differences in circulating markers of angiogenesis and their association with cardiovascular risk factors and cardiovascular disease.

Objective: To determine (a) whether ethnic/racial differences exist in circulating markers of angiogenesis (Angiopoietin-1 (Ang-1), Angiopoietin-2 (Ang-2), soluble Tie-2 receptor (sTie-2) and Angiogenin) between South Asian (SA; from India, Pakistan and Bangladesh); Black African-Caribbean and White (W) ethnic groups, and (b) associations between these markers in stable cardiovascular disease (CVD) and its risk factors.

Patients And Methods: We recruited 243 subjects (82 SA, 84 Black and 77 W) with symptomatic and clinically confirmed CVD (n=108), risk factor controls (with ≥ 1 cardiovascular risk factor, e.g.

Endothelial progenitor cells and circulating endothelial cells in early prostate cancer: a comparison with plasma vascular markers.

Background: Separate studies indicate that endothelial perturbation, as demonstrated by abnormal endothelial progenitor cells (EPCs), circulating endothelial cells (CECs), and plasma markers such as von Willebrand factor (vWf) and soluble E selectin (sEsel) are present in cancer. However, there are no reports where these indices are compared. Accordingly, we hypothesized altered EPCs and CECs in prostate cancer that would correlate with vWf, sEsel, and prostate specific antigen (PSA).

Plasma haemoxygenase-1 in coronary artery disease. A comparison with angiogenin, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1 and vascular endothelial growth factor.

It was the aim of this study to determine plasma haemoxygenase-1 (HO-1) across the spectrum of health, angina but normal coronary arteries (NCA), stable coronary artery disease (CAD), and acute coronary syndromes (ACS), and relationships with angiogenin, matrix metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase-1, and vascular endothelial growth factor. Plasma markers were measured (ELISA) in peripheral venous citrated plasma from 50 healthy subjects, 30 with NCA, 70 with stable CAD and 24 with an ACS, and from patient's aortic root, coronary ostium, coronary sinus and femoral artery. Human umbilical vein endothelial cells (HUVECs) were cultured with or without tumour necrosis factor (TNF), and platelets were probed.

Characterisation and validity of inflammatory biomarkers in the prediction of post-operative atrial fibrillation in coronary artery disease patients.

Atrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG). We sought to determine the diagnostic validity of plasma biomarkers of i) inflammation (marked by interleukin-6 [IL-6] and high-sensitivity C-reactive protein [hs-CRP]), ii) extracellular matrix remodelling (matrix metalloproteinase [MMP-9], tissue inhibitor of matrix metalloproteinase [TIMP-1]) and iii) the prothrombotic state (tissue factor and von Willebrand factor [vWF]) in the risk prediction of post-operative AF. Samples were obtained preoperatively from peripheral/femoral vein and from intracardiac chambers (right atrium [RA], the right atrial appendage [RAA], the left atrium [LA] and the left atrial appendage [LAA]) amongst 100 consecutive patients free of AF and inflammatory disease undergoing elective CABG.

Effects of percutaneous coronary intervention on peripheral venous blood circulating endothelial cells and plasma indices of endothelial damage/dysfunction.

Background: The relationship between endothelial damage/dysfunction and coronary artery disease is well recognized. However, the effects of percutaneous coronary intervention (PCI) [stenting/angioplasty] on circulating markers of endothelial damage/dysfunction (eg, von Willebrand factor [vWF], soluble E-selectin [sEsel] levels, and more recently circulating endothelial cells [CECs]) has been less well defined.

Aims And Methods: We investigated the effects of both diagnostic coronary angiography (CA) [n = 15; blood sampling immediately before CA and 15 min after CA] and PCI (n = 38; blood sampling before PCI, 15 min after PCI, and 24 h after PCI) on levels of CECs, vWF, and sEsel across comparable patient groups.

The effects of exercise stress testing on soluble E-selectin, von Willebrand factor, and circulating endothelial cells as indices of endothelial damage/dysfunction.

Background: The quantification of circulating endothelial cells (CECs) in whole blood is an increasingly recognized index of endothelial damage/dysfunction. Abnormal CECs have been linked to the severity of coronary artery disease (CAD).

Objective: We assessed the relationship of CECs to other markers of endothelial dysfunction (von Willebrand factor (vWF) and soluble E-selectin (sEsel)) during exercise stress testing (EST) in a cohort of patients with suspected CAD.

The effects of coronary artery disease severity on time-dependent changes in platelet activation indices in stored whole blood.

Background: Platelets play a pivotal role in the pathogenesis of the thrombotic complications in cardiovascular disease (CVD). Abnormal platelet activation indices are evolving as potentially useful markers in CVD risk stratification. Whilst there has been some investigation into the effects of storage time on several of these indices, the effects of underlying disease severity on these temporal changes have not been previously studied.