Search

Accumulating data suggest that activity of matrix metalloproteinases (MMPs) is increased in aortic dissection, and in thoracic and abdominal aneurysms. In the present study we sought to determine circulating stromelysin (MMP-3) concentration and its relationship with hypertension-induced aortic root dilatation. The study population included 42 patients with essential hypertension. The subjects were divided into two groups according to echocardiographically measured aortic diameter as those with aortic dilatation (n = 22) and without aortic root dilatation (n = 20). Plasma concentration of MMP-3 was determined by one-step sandwich enzyme immunoassay (EIA) method and compared in both groups. Baseline demographic properties were similar in both groups. Plasma stromelysin (MMP-3) level was significantly higher in patients with aortic dilatation than those without aortic dilatation (5.2 +/- 2.3 vs 3.3 +/- 1.9 ng/ml; P = 0.007). In conclusion, we found that circulating stromelysin (MMP-3) concentration was elevated in hypertension-induced aortic root dilatation.

Objective:We aimed to find out whether there is significant carryover effect which causes false-positive hematuria on red blood cells (RBCs) in automatic urine chemistry (DIRUI H-800) and sediment (DIRUI FUS-200) analyzers.Methods:Twenty-four samples with gross hematuria selected as containing high RBC concentration and forty-eight samples which had both negative result in dipstick and 0/hpf in microscopic examination selected as containing low RBC concentration. Carryover% was calculated via the formula [carryover%=100×(bResults:Carryover% was very high (67%) in urine chemistry analyzer. Carryover% of urine sediment analyzer was found 0.4% whilst false-positive hematuria percentage was 87.5% for the first samples came after gross hematuria and 6.6% for the second samples. The first samples analyzed after gross hematuria had significantly higher (pConclusion:In urine sediment analyzer, carryover% calculated by formula was found analytically sufficient, but it causes highly false-positive results due to diagnostic limit of hematuria (RBC>3/hpf) is low. To prevent carryover in both urine analyzers; washing procedures should be revised and the diagnostic effect of carryover should also be taken into account by biochemists.

Matrix metalloproteinases (MMPs) are involved in the regulation of the extracellular matrix (ECM) of the myocardium and thus the pathogenesis of vascular and cardiac hypertrophy. In this study, we investigated contribution of plasma matrix metalloproteinases to development of left ventricular hypertrophy (LVH) and diastolic dysfunction in hypertensive subjects. Hypertensive patients with (n = 27) and without LVH (n = 23) were included. All participants underwent a complete transthoracic echocardiographic examination, including recordings of the mitral annular early, late, systolic and diastolic velocities by Doppler imaging. Plasma concentrations of MMP-3 and MMP-9 were determined by the one-step sandwich enzyme immunoassay method. Plasma MMP-3 and MMP-9 concentrations were significantly higher in patients with LVH than those without LVH (2.4 +/- 1.2 vs 1.5 +/- 0.7 ng/ml, p = 0.006 and 5.2 +/- 2.8 vs 3.3 +/- 1.7 ng/ml, p = 0.003, respectively). MMP-3 and MMP-9 levels were also correlated with left ventricular posterior wall thickness and Doppler indices of diastolic dysfunction. Our findings have suggested that increased MMP levels may contribute to LVH and left ventricular diastolic dysfunction. Therefore, treatment of hypertension with MMP lowering drugs, such as angiotensin converting enzyme inhibitors and angiotensin receptor blockers, may have favorable effects on LVH and left ventricular diastolic dysfunction.

Vasoactive intestinal polypeptide (VIP) contributes to the regulation of coronary vasomotor tone and circulating levels of VIP have been reported to increase during acute myocardial infarction. However, the changes in VIP concentration during exercise-induced ischemia have not been studied yet. Therefore, we sought to determine whether circulating levels of VIP change during treadmill exercise testing and whether they could be used as a marker of exercise-induced myocardial ischemia. Twenty-nine subjects with definitive positive (group-I) and 20 subjects (group-II) with negative results on treadmill exercise testing were included in this study. In order to assess circulating levels of VIP, blood samples were collected in both groups before exercise, at 5 minutes of exercise, at peak exercise, and at 10 minutes in the recovery period. There were no differences between the two groups with respect to the baseline demographics of age, sex, heart rate, or blood pressure. The metabolic equivalents (METs) values, peak heart rate achieved, peak systolic-diastolic blood pressure, and exercise duration did not differ between the two groups. No significant differences were found in the circulating levels of VIP at any stage of the exercise between the two groups (10.5 +/- 2.5 versus 11.0 +/- 3.5 pmol/L, P = 0.5, 10.6 +/- 2.3 versus 10.6 +/- 3.3 pmol/L, P = 0.9, 10.9 +/- 3.1 versus 11.5 +/- 3.4 pmol/L, P = 0.5, and 10.7 +/- 1.8 versus 11.7 +/- 4.1 pmol/L, P = 0.3, respectively). There was no relationship between the circulating level of VIP and exercise-induced myocardial ischemia, and therefore it could not be used as a marker of exercise-induced myocardial ischemia.

Background Expression of matrix metalloproteinase (MMP) has been shown in aortic dissection and aneurysms indicating increased proteolysis compared with the normal aorta. However, its role in the development of aortic root dilatation has not been studied. We therefore attempted to determine the relationship between aortic root diameter and MMP-9 concentration in a hypertensive population. Methods The 53 hypertensive patients with (n = 27) and without aortic dilatation (n = 26) were included in the study. All participants underwent a complete transthoracic echocardiographic examination including aortic root measurement. Plasma concentration of MMP-9 were determined by the one-step sandwich enzyme immunoassay method and compared in both groups. Results Baseline demographic properties were similar in both groups. No subject had significant valvular disorder and wall motion abnormality on echocardiographic evaluation. On echocardiographic examination only five patients had bicuspid aortic valve. In patients with aortic root dilatation, 21 patients were using an antihypertensive agent, whereas in patients without aortic root dilatation, 19 patients were using an antihypertensive agent. Plasma MMP-9 level was significantly higher in patients with aortic root dilatation than in those without dilatation (2.5 ± 1.0 v 1.6 ± 0.9 ng/mL; P = .003). On correlation analysis, we found a positive correlation between aortic diameter and plasma MMM-9 levels (r = 0.43, P = .001). Conclusions Aortic root dilatation is associated with higher MMP release, which may indicate the role of increased collagenolytic and elastolytic activities in hypertension-induced aortic root dilatation.