Nur Aksoy

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.

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 ≥ 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.

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

SummaryPurposeSystemic 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.MethodsA 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.ResultsIt 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).ConclusionsOur 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.ZusammenfassungZiel der StudieDie systemische Sklerose (SSc) ist eine Erkrankung, die durch Fibrose der Haut und der Organe gekennzeichnet ist; sie ist vergesellschaftet mit einer diffusen fibroproliferativen Mikroangiopathie und einem autoimmunen Hintergrund. Es konnte in verschiedenen Studien gezeigt werden, dass die überschießende Produktion von freien Radikalen und die gesteigerte Kollagensynthese durch Fibroblasten eine wichtige Rolle in der Pathophysiologie der SSc spielen. Prolidase ist ein wichtiger Marker des Turnovers von Kollagen. Ziel unserer Studie war es, den gesamten oxidativen Status (TOS), den gesamten antioxidativen Status (TAS), den oxidativen Stress Index (OSI) und die Serum-Konzentrationen der Prolidase bei Patienten mit SSc und bei gesunden Kontrollen zu erheben. Außerdem untersuchten wir, ob ein Zusammenhang zwischen Prolidase und oxidativem Stress besteht.Methodik38 Patienten mit SSc und 33 gesunde Freiwillige wurden in die Studie aufgenommen. Serum TAS, TOS und Prolidase-Aktivität wurden in beiden Gruppen erhoben.ErgebnisseDie TOS und OSI waren bei den Patienten höher als bei der Kontrolle (P = 0,012 beziehungsweise 0,015). Die TAS unterschied sich allerdings nicht signifikant zwischen beiden Gruppen (P = 0,451). Die Aktivität der Prolidase war bei den Patienten niedriger als bei den Gesunden (P = 0,008). Bei den Patienten bestand eine schwache Korrelation zwischen Prolidase und dem OSI. Bei den Patienten mit Beteiligung der Lunge und des Gastrointestinaltraktes (GI-Trakt) waren die TAS grenzwertig signifikant niedriger (P = 0,067 beziehungsweise 0,059) als bei den Patienten ohne Befall dieser Organe.SchlußfolgerungenUnsere Ergebnisse lassen vermuten, dass der oxidative Stress bei SSc erhöht ist. TAS ist bei Beteiligung der Lungen und des GI-traktes erniedrigt. Eine antioxidative Behandlung könnte daher bei SSc – vor allem wenn Lungen und GI-Trakt befallen sind, von Nutzen sein. Diese Behandlung könnte der Organbeteiligung vorbeugen. TAS könnte ein Marker sein, der das Risiko des Befalls eines bestimmten Organs vorhersagt. Außerdem könnte die Prolidase ein Marker der SSc sein.

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 mol/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 g 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 mol/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.

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 (≥0.02 >g/L) TnT was measured in 33 patients (53%). Compared with patients with normal (<0.02 >g/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.

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

Abstract 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 (≥15μmol/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. Clin Chem Lab Med 2006;44:1324–9.

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.

The neutrophile to lymphocyte ratio and mean platelet volume with Gensini score in patients with acute myocardial infarction

The aim of the present study was to investigate the relationship between the coronary artery severity and neutrophile to lymphocyte ratio (N/L) and also mean platelet volume (MPV) in patients with myocardial infarction (MI). 203 MI with ST elevation (STEMI) patients and 62 MI without ST elevation (NSTEMI) patients were included and retrospectively analyzed in the study. The severity of the coronary artery disease was assessed according to the Gensini score. Neutrophil counts were 12.5±4.1 and 11.3±3.1 in the STEMI and NSTEMI groups respectively(p=0.045). N/L ratio was 5.1±6.0 and 5.2±6.0 respectively (p=0.85) and MPV was 8.6±1.2 and 8.4±1.0 respectively (p=0.44). Mean Gensini score was 36.8±16.1 in the STEMI group and 29.7±13.9 in the NSTEMI group (p<0.002). MPV was significantly correlated with Gensini score but there was no significant correlation between the N/L ratio and Gensini score in the STEMI group(r=0.07, p=0.27 and r=0.17, p=0.01 respectively). In the NSTEMI group, correlation of neither N/L ratio nor MPV with Gensini score was not detected (r=0.12, p=0.33 and r=0.08, p=0.53 respectively). MPV is a valuable parameter to predict