Biomedical subjects

Ender Semiz

Publications and source records attributed to Ender Semiz.

6 recordsLinked to original sources

PubMed2004

Association between paraoxonase-1 activity and lipid peroxidation indicator levels in people living in the Antalya region with angiographically documented coronary artery disease.

BACKGROUND: Paraoxonase-1 (PON1) is a high-density lipoprotein (HDL)-associated enzyme capable of hydrolyzing lipid peroxides. Thus, PON1 plays a preventing role in atherosclerosis by protecting against lipid peroxidation. HYPOTHESIS: The incidence of coronary artery disease (CAD) is high in the Turkish population, and many risk factors have been studied as determinants of CAD. In Turkish people living in the Antalya region, we aimed to determine serum PON1 activity and its relation to lipoproteins and lipid peroxidation markers. METHODS: We measured the activity of serum PON1 together with concentrations of a variety of lipid constituents--total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), HDL cholesterol (HDL-C), triglycerides (TG), apolipoprotein (apo) A-I, apoB, and lipid peroxidation indicators (conjugated diene [CD] and thiobarbituric acid-reactive substances [TBARS])--in 108 patients with CAD and 64 healthy subjects (controls). RESULTS: We found that the PON1 activity was significantly reduced in patients with CAD (222.37 +/- 11.31 IU/l) compared with controls (331.75 +/- 20.98 IU/l). These patients had significantly lower HDL-C, PON1/HDL-C, apoA-I, PON1/ApoA-I, and ApoA-I/ApoB, and higher LDL-C, TC/HDL-C, LDL-C/HDL-C, apoB, CD and TBARS than did controls. Total cholesterol and apoA-I concentrations were significantly higher in women than in men in both groups. After multiple logistic regression analysis, TBARS (odds ratio [OR] 568.87; p = 0.000), age (OR 1.10; p = 0.000), gender (OR 4.58; p = 0.008), apoA-I/apoB (OR 0.046; p = 0.003), and PON1/apoA-I (OR 0.58; p = 0.007) were independently indicative of the presence of CAD. CONCLUSIONS: This is the first report of decreased serum PON1 activity and increased lipid peroxidation indicators (CD and TBARS) of patients with CAD living in Antalya, Turkey. Our results indicate that TBARS levels, age, gender, apoA-1/ApoB, and PON1/apoA-I ratios are important markers of CAD.

Adult↗

PubMed2003

Heart rate variability in patients with rheumatoid arthritis.

Heart rate variability (HRV) is a useful tool for the detection of sympathetic-parasympathetic balance in the autonomic nervous system. Autonomic nervous system involvement in patients with rheumatoid arthritis (RA) has rarely been studied and has shown conflicting results. Our purpose was to determine if HRV showed changes in patients with RA in comparison with the normal population. Short-term analysis of HRV was performed for time-domain frequency in 42 patients with RA and 44 matched controls. In this analysis, patients displayed lower standard deviation of the mean than healthy subjects ( P<0.0001). Patients tended to display higher pNN50 and root-mean-square of successive difference values than did healthy subjects, but these differences were not statistically significant (P >0.05). In frequency domain analysis, the spectral measures of HRV showed reduced high-frequency (HF) values and an higher low-frequency (LF) values; as a result, the ratio between low and high frequencies (LF/HF), representative of sympathovagal modulation, was significantly increased (P=0.001, P=0.012, and P=0.003, respectively). Our data suggest an increase in sympathetic control of the heart rate in patients with RA. This increased sympathetic activity could play a key role in the development of ventricular tachyarrhythmias in RA and may be related to the higher incidence of sudden death in this disorder.

Arrhythmias, Cardiac↗

PubMed2003

Hypocalcemic cardiomyopathy due to untreated hypoparathyroidism.

Hypocalcemic cardiomyopathy due to hypoparathyroidism is a very rare condition which is usually refractory to conventional treatment for cardiac failure but which responds favorably to restoration of normocalcemia. A 55-year-old man and a 46-year-old woman with a history of postoperative hypoparathyroidism presented with symptoms of cardiac failure and hypocalcemia. A presumptive diagnosis of dilated cardiomyopathy was considered by echocardiography and endomyocardial biopsies were consistent with cardiomyopathy. The coronary angiograms were normal and there was no apparent cause for dilated cardiomyopathy in these patients. The history of the patients and partial recovery of cardiac function after restoration of normocalcemia suggest that hypocalcemia was the cause of dilated cardiomyopathy.

Cardiomyopathy, Dilated↗

PubMed2003

Comparison of initial efficacy and long-term follow-up of heparin-coated Jostent with conventional NIR stent.

The implantation of heparin-coated stents was reported to be well tolerated, but there are conflicting results about acute in-hospital complications. (sub)acute thrombosis rates, and long-term follow-up compared to uncoated stents. We compared the angiographic and clinical results after coronary placement of two stent models: the heparin-coated premounted Jostent and the uncoated premounted NIR stent. Of 710 patients revascularized, a total of 426 patients received Jostent (n = 230) or NIR stent (n = 196) implantation. The primary end points were acute or subacute thrombosis, urgent CABG, AMI or death, while the secondary end points were the comparison of the restenosis rates of the stents at the 6th month and of the functional angina classification of the stent groups at the 1st, 6th and 12th months. There were no significant differences between the Jostent and NIR stent groups regarding angiographic and procedural success. Acute thrombosis rates in the Jostent and NIR stent groups were similar while no subacute thrombosis was observed in either group. The major adverse cardiac event rates of the groups also did not differ. Angiographic restenosis occurred in 17% of the Jostent group and 16% of the NIR stent group (NS). The combined clinical and angiographic restenosis rate was also similar between the Jo and NIR groups (19% and 18%, respectively). Comparison of functional angina classes at the 1st, 6th and 12th months revealed no significant difference between the study groups. In conclusion, when compared with implantation of an uncoated premounted NIR stent, implantation of a heparin-coated premounted Jostent does not provide any more benefit with respect to initial efficacy, sub(acute) thrombosis and 6-month restenosis rates and 12-month clinical outcomes.

Aged↗

PubMed2003

[Mitral valve prolapse syndrome: orthostatic hypotension and physiopathology of its clinical symptomathologies].

Although several investigations on mitral valve prolapse syndrome (MVPS) have been performed, clinical symptoms of this syndrome are not yet clarified. Atypical chest pain, palpitations, fatigue, dyspnea and anxiety are the most frequent symptoms associated with this syndrome. However, dizziness and syncope may be serious symptoms in MVPS. Dizziness and syncope are related to cardiac arrhythmias and are proposed to distinguish types, frequency of arrhythmias and relation to the symptoms. Orthostatic hypotension and tachycardia rarely occur in MVPS. The physiopathological mechanisms of these symptoms are not known clearly, but multifactorial causes are thought to be responsible including autonomic dysfunction, hyperadrenergic state, abnormalities in regulation of baroreceptors, parasympathetic derangements, decrease of intravascular volume, abnormal renin-aldosterone response to depletion of intravascular volume and abnormal release of atrial natriuretic factor.

Dizziness↗

PubMed2003

[Ischemic preconditioning].

It has been shown that repeated brief coronary occlusions increase myocardial resistance towards prolonged episodes of ischemia. This phenomenon, which renders the heart more tolerant to ischemia with subsequent limitation of infarct size, has been termed ischemic preconditioning. Ischemic preconditioning also protects the heart against postinfarction left ventricular dysfunction and ventricular arrhythmias. Ischemia induced activation of adenosine receptors, and opening of ATP-sensitive potassium channels and stress protein synthesis are thought to be the potential mechanisms of this phenomenon. The exploration of the exact mechanisms of ischemic preconditioning might improve the treatment strategies for acute myocardial infarction in the future.

Humans↗