Plasma urotensin II as a marker for severity of rheumatic valve disease.

In developing countries, rheumatic valve disease (RVD) is still prevalent. Management of RVD depends on symptomatology, physical examination and echocardiographic evaluation, all of which, however, might be inadequate. Reliable biomarkers to establish severity of RVD and predict complications would be highly beneficial. Urotensin II is regarded as a cardiovascular autacoid/hormone, and its role in cardiovascular diseases is emerging. We hypothesized urotensin II might have pathophysiological roles in RVD. We investigated 71 patients with RVD (mean age 40 +/- 12 years, 17 female patients) and 25 normal subjects (mean age 40 +/- 7 years, 8 female patients). We assessed their New York Heart Association (NYHA) functional class, RVD severity and pulmonary artery pressure (PAP), and measured plasma urotensin II levels. Mitral regurgitation (r = 0.226, p = 0.02), tricuspid regurgitation (r = 0.238, p = 0.02), PAP (r = 0.320, p = 0.01), and NYHA class (r = 0.213, p = 0.03) correlated positively with urotensin II levels. There was positive correlation between urotensin II levels and severity of mitral regurgitation (r = 0.248, p = 0.01) and tricuspid regurgitation (r = 0.326, p = 0.001). In linear regression analysis, only PAP was predictive of urotensin II (beta = 0.3; p = 0.02). In conclusion, this is the first study showing that plasma urotensin II is elevated in chronic RVD, associated with severe mitral and tricuspid valve regurgitation. Furthermore, urotensin II level is correlated with NYHA functional class, and the increase in PAP is predictive of plasma urotensin II.

Contribution of renal function impairment to unexplained troponin T elevations in congestive heart failure.

BACKGROUND: Patients with severe congestive heart failure (CHF) often have unexplained elevations in serum concentrations of troponin T (TnT), and it is proposed that this is due to cardiac TnT release because of underlying cardiac disease. We investigated whether impaired renal function is an additional underlying phenomenon contributing to increased TnT levels in patients with CHF. METHODS: Sixty-two patients with nonischemic CHF, New York Heart Association (NYHA) class III-IV, with normal coronary angiogram and normal serum creatinine were included in the study. Baseline glomerular filtration rate (GFR) was calculated using the Cockcroft Gault equation. RESULTS: Although mean creatinine level was normal (0.92 +/- 0.17 mg/dL), mean GFR was low (56 +/- 16 mL/min) in the cohort. Elevated (>or=0.02 microg/L) TnT was measured in 33 patients (53%). Compared with patients with normal (<0.02 microg/L) TnT levels, patients with elevated TnT had significantly higher NYHA class (p = 0.02), longer duration of disease (p = 0.02), lower GFR (p = 0.0001), and lower LVEF (p = 0.0001). There were significant associations between TnT levels and duration of disease (r = 0.29, p = 0.01), creatinine (r = 0.30, p = 0.01), GFR (r = -0.55, p < 0.0001), and LVEF (r = -0.39, p = 0.001). Independence of these associations was evaluated in multiple linear regression analysis, and serum TnT was independently and negatively associated only with GFR (p = 0.005). CONCLUSIONS: Renal function (GFR) correlated significantly and more strongly than cardiac function (LVEF) with the serum TnT levels in patients with CHF. This supports our hypothesis that impaired renal function causes the accumulation of troponin and is very likely the cause of unexplained elevations of serum TnT in patients severe CHF.

Evaluation of the mobile phone electromagnetic radiation on serum iron parameters in rats.

BACKGROUND: Electromagnetic fields (EMF) created by mobile phones during communication have harmful effects on different organs. OBJECTIVES: It was aimed to investigate the effects of an EMF created by a mobile phone on serum iron level, ferritin, unsaturated iron binding capacity and total iron binding capacity within a rat experiment model. METHODS: A total of 32 male Wistar albino rats were randomly divided into the control, sham, mobile phone speech (2h/day) and stand by (12 h/day) groups. The speech and stand by groups were subjected to the EMF for a total of 10 weeks. RESULTS: No statistically significant difference was observed between the serum iron and ferritin values of the rats in the speech and stand by groups than the control and sham groups (p>0.05). The unsaturated iron binding capacity and total iron capacity values of the rats in the speech and stand by groups were significantly lower in comparison to the control group (p<0.01). CONCLUSION: It was found that exposure to EMF created by mobile phones affected unsaturated iron binding capacity and total iron binding capacity negatively.

Does exercise-induced severe ischaemia result in elevation of plasma troponin-T level in patients with chronic coronary artery disease?

OBJECTIVE: It has been reported that the loss of cell membrane integrity during severe reversible ischaemia results in elevation of plasma troponin T (TnT) in unstable angina. We investigated whether TnT is released into circulation during severe ischaemia (e.g. on treadmill exercise testing) in patients with chronic coronary artery disease (CAD). METHODS AND RESULTS: The study comprised 54 patients who had angiographically documented CAD (22 of them had a prior history of myocardial infarction) and 18 normal subjects. All cases underwent exercise thallium (Tl)-201 SPECT myocardial perfusion imaging. Blood samples for TnT analysis were obtained for each patient at pre-exercise, immediately after and 12 hours after exercise. SPECT images were divided into 20 segments. Patients with redistribution defects > or = 5 were considered to have severe ischaemia. Sixteen patients had severe ischaemia on SPECT images. The mean TnT levels of the patients with severe ischaemia at pre-exercise, immediately after and 12 hours after exercise were 0.009 +/- 0.008, 0.012 +/- 0.009 and 0.010 +/- 0.010 ng/ml, respectively. In normal subjects the mean TnT levels were 0.012 +/- 0.009, 0.010 +/- 0.009, 0.010 +/- 0.010 ng/ml, respectively. There was no significant difference neither between the two groups nor within each group with respect to pre-exercise and post-exercise TnT results. All TnT levels were within normal limits (< 0.1 ng/dl). Additionally, when the patients were grouped according to other SPECT variables (patients with reversible defects vs. fixed defects; patients with increased lung uptake of Tl-201 vs. without lung uptake; patients with transient left ventricle dilatation vs. those without) and angiographic findings (patients with multivessel disease vs. normal subjects), there were no significant differences with respect to pre-exercise and post-exercise TnT results. CONCLUSION: Severe ischaemia does not result in the elevation of the plasma TnT level in patients with chronic CAD.

Effect of homocysteine-lowering therapy on vascular endothelial function and exercise performance in coronary patients with hyperhomocysteinaemia.

OBJECTIVE: This study was performed to determine the effect of homocysteine-lowering therapy (HLT) on endothelium-dependent vasodilation (EDD) and exercise performance in patients with coronary artery disease. METHODS AND RESULTS: Among the patients who were on the waiting list for coronary intervention, 26 male patients (plasma homocysteine (Hcy) levels > 15 micromol/l) who had a focal stenosis of at least 70% in the left anterior descending artery were included in the study. The patients were matched to receive HLT (n = 15; 0.4 mg of folic acid, 2 mg vitamin B6 and 6 microg of vitamin B12) or placebo (n = 11) until the coronary intervention was performed (mean 3.8 +/- 0.9 weeks). Brachial artery vasomotion test and treadmill stress testing were performed at baseline and 4 weeks after HLT before the time of coronary intervention in each patient. Hcy levels were found to be decreased significantly after HLT compared to baseline (23.4 +/- 6 vs. 11.3 +/- 4 micromol/l; p < 0.001) whereas placebo had no effect. HLT but not placebo produced a marked improvement in EDD, from 3.9 +/- 1.1% to 9.4 +/- 2.3% (p < 0.0001). Endothelium-independent nitroglycerin-induced dilation was similar in the HLT and placebo groups compared with the baseline. In the exercise testing, HLT resulted in a significant improvement in exercise duration and reduction in the amount of maximal ST-segment depression, (from 6.5 +/- 2 to 6.9 +/- 2 min, p = 0.02 and from 1.2 +/- 0.7 to 0.8 +/- 0.5 mm, p = 0.01, respectively) whereas placebo did not. CONCLUSION: Lowering Hcy levels improves EDD and exercise performance while reducing the exercise-induced myocardial ischaemia in patients with coronary heart disease and hyperhomocysteinaemia.

Evaluation of oxidant and antioxidant status and relation with prolidase in systemic sclerosis.

PURPOSE: Systemic sclerosis (SSc) is a disease characterized by fibrosis of the skin and organs; it is associated with diffuse fibroproliferative microangiopathy and autoimmune background. The studies have shown that the production of excessive free radicals and increased collagen synthesis by the fibroblasts play an important role in the pathophysiology of SSc. Prolidase is an important marker in collagen turnover. We aimed to compare total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), and prolidase levels of SSc patients and healthy controls. We also investigated the relationship between prolidase and oxidative stress. METHODS: A total of 38 SSc patients and 33 healthy volunteers were included in the study. Serum TAS, TOS, and prolidase activity were evaluated in the groups. RESULTS: It was found that the TOS and OSI levels of patients were higher than those in the control group (P = 0.012 and 0.015, respectively), whereas TAS was not significantly different between groups (P = 0.451). Prolidase activity was lower in patients than in controls (P = 0.008). There was a weak correlation between prolidase and OSI in patients. It was found that TAS was lower by marginal significance in the patients with lung and gastrointestinal tract (GT) involvement than the patients without those (P = 0.067 and 0.059, respectively). CONCLUSIONS: Our data suggest that oxidative stress is increased in SSc. TAS is decreased in patients with lung and GT involvement. These results support that antioxidant treatment may be useful in SSc, especially in patients with lung and GT involvement. Antioxidant treatment may prevent organ involvement in SSc. TAS may be a marker that predicts the risk of involvement of a specific organ. In addition, prolidase may be a marker of SSc.

Effect of pistachio diet on lipid parameters, endothelial function, inflammation, and oxidative status: a prospective study.

OBJECTIVE: Recent studies have suggested that nuts have favorable effects beyond lipid lowering. We aimed to investigate effect of the Antep pistachio (Pistacia vera L.) on blood glucose, lipid parameters, endothelial function, inflammation, and oxidation in healthy young men living in a controlled environment. METHODS: A Mediterranean diet was administered to normolipidemic 32 healthy young men (mean age 22 y, range 21-24) for 4 wk. After 4 wk, participants continued to receive the Mediterranean diet but pistachio was added for 4 wk by replacing the monounsaturated fat content constituting approximately 20% of daily caloric intake. Fasting blood samples and brachial endothelial function measurements were performed at baseline and after each diet. RESULTS: Compared with the Mediterranean diet, the pistachio diet decreased glucose (P<0.001, -8.8+/-8.5%), low-density lipoprotein (P<0.001, -23.2+/-11.9%), total cholesterol (P<0.001, -21.2+/-9.9%), and triacylglycerol (P=0.008, -13.8+/-33.8%) significantly and high-density lipoprotein (P=0.069, -3.1+/-11.7%) non-significantly. Total cholesterol/high-density lipoprotein and low-density lipoprotein/high-density lipoprotein ratios decreased significantly (P<0.001 for both). The pistachio diet significantly improved endothelium-dependent vasodilation (P=0.002, 30% relative increase), decreased serum interleukin-6, total oxidant status, lipid hydroperoxide, and malondialdehyde and increased superoxide dismutase (P<0.001 for all), whereas there was no significant change in C-reactive protein and tumor necrosis factor-alpha levels. CONCLUSION: In this trial, we demonstrated that a pistachio diet improved blood glucose level, endothelial function, and some indices of inflammation and oxidative status in healthy young men. These findings are in accordance with the idea that nuts, in particular pistachio nuts, have favorable effects beyond lipid lowering that deserve to be evaluated with prospective follow-up studies.

Enzyme levels and G-463A polymorphism of myeloperoxidase in chronic lymphocytic leukemia and multiple myeloma.

The aim of this study was to investigate how myeloperoxidase (MPO) G-463A gene polymorphism and enzyme levels varied among patients with chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) and to find the relationship between the MPO gene, enzyme levels, and clinical parameters. We studied the sera from 40 healthy volunteers, patients with CLL (n = 34) and MM (n = 28). In subjects with homozygote GG genotype, MPO levels were higher in the patients with both CLL and MM than in the control group. This difference was statistically significant in patients with CLL. In conclusion, homozygote GG genotype is found to be associated with an increasing amount of serum MPO. In accordance with the results of the study, we assess that the increase in the MPO enzyme level in the patient groups with CLL and MM generated bactericidal effects as well as the increased formation of ROP, thus setting off a pro-cell death pathway and playing a role on the pathogenesis of lymphoproliferative malignancies through this mechanism.

Pistachio intake increases high density lipoprotein levels and inhibits low-density lipoprotein oxidation in rats.

There is increasing evidence that nuts have protective effects against coronary artery disease by improving lipid profile and inhibiting lipid oxidation. However, data about pistachio nuts are limited, and to our knowledge, there is no study investigating the effects of pistachio intake on lipid oxidation and serum antioxidant levels. This study, therefore, sought to determine the effects of pistachio intake on serum lipids and determine whether consumption of pistachio would alter serum antioxidant levels. Rats were randomly divided into three groups (n=12 for each): control group fed basic diet for 10 weeks and treated groups fed basic diet plus pistachio which constituted 20% and 40% of daily caloric intake, respectively. Consumption of pistachio as 20% of daily caloric intake increased high-density lipoprotein (HDL) levels and decreased total cholesterol (TC)/HDL ratio, compared with those not taking pistachio. However, TC, low-density lipoprotein (LDL) cholesterol and triglyceride levels were unaffected by pistachio consumption. Consumption of pistachio as 20% of daily caloric intake increased serum paraoxonase activity by 35% and arylesterase activity by 60%, which are known to inhibit LDL cholesterol oxidation, compared with the control group. However, increased antioxidant activity was blunted when pistachio intake was increased to 40% of daily caloric intake. In conclusion, the present results show that consumption of pistachio as 20% of daily caloric intake leads to significant improvement in HDL and TC/HDL ratio and inhibits LDL cholesterol oxidation. These results suggest that pistachio may be beneficial for both prevention and treatment of coronary artery disease.

Increased homocysteine in heart failure: a result of renal impairment?

BACKGROUND: Hyperhomocysteinemia may constitute a risk factor for patients with severe heart failure. This study examines the relationship between plasma homocysteine concentration and left ventricular ejection fraction with renal function in heart failure patients free of coronary artery disease. METHODS: Left ventricular ejection fraction was documented in 62 patients with advanced heart failure who had no proven significant coronary artery stenosis. Glomerular filtration rate was measured using the Cockroft-Gault equation. RESULTS: Elevated homocysteine levels (>or=15 micromol/L) were detected in 22 patients. Low glomerular filtration rate was observed in patients who had normal serum creatinine concentration. Homocysteine was strongly correlated with age, duration of disease, left ventricular ejection fraction, serum creatinine, and glomerular filtration rate. Statistically significant trends were observed across respective homocysteine quartiles. However, by multivariate regression, the strongest predictor of homocysteine was the glomerular filtration rate. CONCLUSIONS: Impaired renal function leads to a diminished clearance rate, which can be a prominent pathophysiological mechanism in the elevation of homocysteine concentration in heart failure.

Acute rest perfusion imaging in high risk unstable angina: association with troponin T and clinical endpoints.

BACKGROUND: Troponin T (TnT) and rest perfusion imaging (RPI) have been reported to be important diagnostic tools for risk stratification in patients with chest pain. METHODS: We investigated the association between two methods in 60 patients presenting with typical chest pain at rest within the last 6 h before admission. All patients underwent Tc-99m gated SPECT imaging and serial TnT measurements and were followed for occurrence of adverse cardiac events up to 30 days. RESULTS: Perfusion defect was detected in 42 patients and elevated TnT was observed in 23 patients. All of the patients with an elevated TnT have also perfusion defect in RPI. Half of the patients with normal TnT level (51%) presented a perfusion defect detected by RPI (p = NS). The patients with elevated TnT levels had more perfusion defect numbers than those with normal TnT levels (8.2 +/- 2.9 vs. 5.3 +/- 2.2; p = 0.0007). Cardiac events occurred in 38 patients (14 MI, 24 revascularisation). In predicting cardiac events, RPI and TnT had sensitivities (97 vs. 58%; p < 0.001), specificities (77 vs. 95%, p = NS), positive predictive values (PPV) (88 vs. 96%; p = NS) and negative predictive values (NPV) (94% vs. 57%; p = NS), respectively. In predicting MI, the two tests had sensitivities (93 vs. 93%; p = NS), specificities (37 vs. 78%; p < 0.001), PPVs (31 vs. 57%; p = NS) and NPVs (94 vs. 97%; p = NS), respectively. CONCLUSIONS: These results suggest that in patients with rest angina (1) TnT elevation is associated with the extent of myocardial perfusion defect; (2) both tests are valuable, while positive RPI is more sensitive in predicting all cardiac events irrespective of TnT; both positive TnT and positive RPI predict a high probability to have MI; (3) both negative test results predict a very low probability to have cardiac event, including MI.