Joop H. M. Schreur

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Assessment of free cytosolic [Ca2+] ([Ca2+]c) using the acetoxymethyl ester (AM) form of indo-1 may be compromised by loading of indo-1 into noncytosolic compartments, primarily mitochondria. To determine the fraction of noncytosolic fluorescence in whole hearts loaded with indo-1 AM, Mn2+ was used to quench cytosolic fluorescence. Residual (i.e.,(More)
OBJECTIVES This study sought to demonstrate the feasibility of a dedicated algorithm for automated quantification of stenosis severity on multislice computed tomography in comparison with quantitative coronary angiography (QCA). BACKGROUND Limited information is available on quantification of coronary stenosis, and previous attempts using semiautomated(More)
We asked whether thyroid hormone (T4) would improve heart function in left ventricular hypertrophy (LVH) induced by pressure overload (aortic banding). After banding for 10-22 wk, rats were treated with T4 or saline for 10-14 d. Isovolumic LV pressure and cytosolic [Ca2+] (indo-1) were assessed in perfused hearts. Sarcoplasmic reticulum Ca2+-ATPase (SERCA),(More)
Limited time resolution has hampered proper evaluation of changes in intracellular Na+ (Na+i) in whole hearts upon post-ischemic reperfusion. In isolated rat hearts perfused at 37 degrees C, we studied the contribution of the Na+-K+ ATPase and the Na+-H+ exchanger to control of Na+i during reperfusion using 23Na NMR and the shift reagent Tm(DOTP)5- with a(More)
BACKGROUND Although atrial fibrillation (AF) has been linked to underlying coronary artery disease (CAD), data supporting this association have been based on ECG and clinical history for the definition of CAD rather than direct visualization of atherosclerosis. METHODS AND RESULTS The prevalence of CAD among patients with paroxysmal or persistent AF and(More)
The fluorescent indicator indo-1 is widely used to monitor intracellular calcium concentration. However, quantitation is limited by uncertain effects of the intracellular environment on indicator properties. The goal of this study was to determine the effects of protein and acidosis on the fluorescence spectra and calcium dissociation constant (Kd) of(More)
Both cytosolic free Ca2+ ([Ca2+]i) decline and myocardial relaxation are slowed in severe hypertrophy and heart failure. However, it is not certain whether this occurs in mild to moderate hypertrophy. Therefore, we tested the hypotheses that slowing of [Ca2+]i decline 1) occurs in mild to moderate hypertrophy, 2) occurs in the absence of slowed relaxation,(More)
BACKGROUND.: Asian Indian migrants in the Western world are highly susceptible for ischaemic heart disease (IHD). Until now, most IHD risk studies were performed in first and second generation Asian Indian expatriates. For optimal prevention, knowledge of the cardiovascular risk profile of younger generations is crucial. METHOD.: In a cross-sectional study(More)
OBJECTIVES To compare magnetic resonance myocardial perfusion imaging (MRI) with anatomical assessment by multislice computed tomography (MSCT) coronary angiography and conventional coronary angiography. DESIGN AND PATIENTS In this prospective study, 53 patients (60% male, average age 57+/-9 years, 83% intermediate pre-test likelihood) underwent 1.5 T(More)
Atrial fibrillation (AF) has been linked to the presence of underlying coronary artery disease (CAD). However, whether the higher burden of CAD observed in AF patients translates into higher burden of myocardial ischemia is unknown. In 87 patients (71% male, mean age 61 ± 10 years) with paroxysmal or persistent AF and without history of CAD, MSCT coronary(More)