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    A high oxidative stress index predicts endothelial dysfunction in young male smokers
    (Comenius Univ, 2013) Karahan, O.; Manduz, S.; Bektasoglu, G.; Zorlu, A.; Turkdogan, K. A.; Bozok, S.
    Experimental studies have shown that smoking was related to endothelial dysfunction via oxidative stress. However, the degree of oxidative stress to be associated with endothelial dysfunction is unknown. Oxidative stress index (OSI) might be a useful and easy way of determining the endothelial dysfunction. Hence, we aimed to evaluate the relationship between OSI and flow mediated dilatation (FMD) in smoking healthy male volunteers. Eighty smoking healthy male volunteers were enrolled in the study. Participants were classified as having normal and abnormal FMD response. In an univariate analysis; systolic and diastolic blood pressures, C-reactive protein (CRP), low-density lipoprotein cholesterol, OSI and lipid peroxidation (LPO) levels were predictive for abnormal FMD response. In a multivariable logistic regression analysis with forward stepwise method, OSI (OR: 3.194, 95% CI: 1.710-5.966, p<0.001) and CRP (OR: 2.082, 95% Cl: 1.101-3.939, p 0.024) were found to be independent parameters for predicting abnormal FMD response in young male smokers. The optimal cut-off value of OSI for detecting abnormal FMD response was found to be >3.35, with 100 % sensitivity and 84.1 % specificity. We have shown that critical endothelial dysfunction can easily be detected by OSI in individuals, at risk for developing coronary artery disease, such as smokers (Tab. 3, Fig. 3, Ref. 30). Text in PDF www.elis.sk.
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    Iloprost reduces myocardial edema in a rat model of myocardial ischemia reperfusion
    (Sage Publications Ltd, 2014) Caliskan, A.; Yavuz, C.; Karahan, O.; Yazici, S.; Guclu, O.; Demirtas, S.; Mavitas, B.
    Objective: Myocardial ischemia severely reduces myocyte longevity and function. Extensive interstitial edema and cell damage occur as a result of myocardial reperfusion injury. Current therapies are directed at prevention of ischemia-induced damage to cardiac tissue. Iloprost is a novel pharmaceutical agent for the treatment of ischemia. Methods: Twenty rats were segregated into four experimental groups. The procedure control group consisted of four rats undergoing a sham operation. The remaining 16 rats were divided into two equal groups. The first group (control group) received a continuous intravenous infusion of physiological serum immediately prior to the procedure. Iloprost was administered by a continuous intravenous infusion into the right jugular vein at an infusion rate of 100 ng/kg/min for 30 minutes prior to reperfusion in the experimental group (study group). Following the infusion treatments, ligation of the left coronary artery was conducted for 30 minutes to induce myocardial ischemia. The rats were euthanized 24 hours after reperfusion and cardiac tissue was harvested from all specimens for analysis. Results: Histological examination revealed three myocardial tissue specimens with grade II damage and five myocardial tissue specimens with grade III reperfusion injury in the control group. However, the study group consisted of two grade III myocardial tissue specimens, five grade 11 myocardial tissue specimens and one grade 1 myocardial tissue specimen. Moreover, a statistically significant reduction in myocardial edema was observed in the study group (p=0.022). Conclusion: Our results support the hypothesis that iloprost enhances protection against cardiac ischemia reperfusion injury. This protective effect may be associated with vasodilation, antioxidant or anti-edema mechanisms.
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    THE RELATIONSHIP BETWEEN QT DISPERSION AND EXAGGERATED BLOOD PRESSURE RESPONSE TO EXERCISE STRESS TESTING
    (Elsevier Ireland Ltd, 2013) Ertas, F.; Yavuz, C.; Kaya, H.; Karahan, O.; Demirtas, S.; Acet, H.; Oylumlu, M.
    [Abstract Not Available]
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    Serum estradiol/free testosterone ratio can be important predictor for varicose vein recurrence in men
    (Edizioni Minerva Medica, 2015) Ozcan, S.; Tezcan, O.; Kurt, T.; Turkone, H.; Karahan, O.; Caliskan, A. T.; Adam, G.
    Aim. Recurrent varicose veins are a frustration for both the patient and the surgeon. More investigation of the exact diagnosis, proper practice, and causes for the recurrence of varicose veins is needed. Methods. We investigated a total number of 187 patients in a five year period with an estradiol-2/free testosterone (E2/fT) ratio relationship on recurrent varicose veins in men between the ages of 20-50. Fifity years was the maximum age due to the age dependent sex steroid hormone regression that occurs after this age, which may interefere with the assessment. Fifty three men with an elevated E2/fT ratio (group A), and 143 men with no endocrinologic problems (group B) were enrolled in the study and had surgery for varicose veins. After 5 years follow up (mean 3 years), Group A (N.=29) and group B (N.=43) had recurrent varicose veins by clinical and radiologic findings. Venous blood samples were driven from all patients of both groups in the morning to detect the levels of serum E2 and fT levels. Patient history of surgery for varicose veins, physical examination, color duplex ultrasound of both limbs, and classification of CEAP were performed in both groups. Results. The serum E2/fT ratio was significantly higher in Group A (5.21 +/- 0.56) compared to group B (2.54 +/- 0.27) in the recurrent varicose vein groups (p <= 0.05). Moreover, there was a high correlation between serum E2/fT ratio and the CEAP clinical classification in group A (5) compared to group B (2) (P <= 0.05). Also, recurrence rate was higher in group A (54%) compared to group B (32%)(P <= 0.05). Conclusion. Elevated serum E2/fT ratio is a precipitating factor for recurrent varicose veins in male patients.
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    Serum ischaemia-modified albumin level is an irrelevant predictive factor for ischaemic duration in mesenteric ischaemia
    (Sage Publications Ltd, 2014) Caliskan, A.; Yavuz, C.; Karahan, O.; Demirtas, Sinan; Yazici, S.; Guclu, O.; Mavitas, B.
    Background: Acute mesenteric ischaemia is an emergency condition that requires urgent and expeditious diagnosis and immediate surgical or medical intervention. The initial hours are critical for the recovery of the affected bowel segment. Thus, its clinic diagnostic biomarkers are important when it comes to reducing mortality and morbidity rates. Methods: Twenty-four male Sprague-Dawley rats were included in the study. The rats were divided into three equal groups.Those in Group I were sacrificed to determine the basal serum values of ischaemia-modified albumin (IMA) after a simple laparotomy.The superior mesenteric artery (SMA) was clamped in a simple laparotomy in Groups II and III; blood samples were taken at 120 minutes in Group II and 360 minutes in Group III.The serum IMA levels were identified from the blood samples and the results obtained were compared statistically. Results:The serum IMA levels were determined to be 22 +/- 6 (22) mu/L, 34 +/- 7 (34) mu/L and 36 +/- 4 (37) mu/L in Groups I, II and III, respectively.The differences between the groups were not statistically significant. Conclusion: Our results showed that the serum IMA level is not an appropriate biomarker for acute mesenteric ischaemia. Additionally, the IMA level is not an appropriate biomarker for the detection of ischaemia duration. However, future studies should be conducted to clarify the efficacy of serum IMA levels under different ischaemic conditions.
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    Using oxidant and antioxidant levels to predict the duration of both acute peripheral and mesenteric ischemia
    (Sage Publications Ltd, 2014) Yazici, S.; Demirtas, S.; Guclu, O.; Karahan, O.; Yavuz, C.; Caliskan, A.; Mavitas, B.
    Objective: The aim of this study was to determine the relationship between oxidative stress markers and the duration of ischemia in rat mesenteric and peripheral ischemia models. Methods: Forty rats were divided into five equal groups, as follows: rats in Group I (control group) were sacrificed to determine the baseline characteristics of the serum markers; the superior mesenteric artery was clamped via a simple laparotomy to induce mesenteric ischemia in Groups II and III; the right common femoral artery was clamped to induce peripheral ischemia in Groups IV and V. Blood samples were taken at 2 (Groups II and IV) and 6 (Groups III and V) hours after these procedures. The serum total oxidative status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI) and paraoxonase-I (PON-I) enzyme activities were evaluated in the samples obtained from each group. Results: The OSI level of the control group was 91.00+/-5.46 (mean +/- SD). The OSI levels taken 2 hours after the induction of mesenteric ischemia and peripheral ischemia were significantly higher (194.50+/-11.16 and 301.75+/-19.98, respectively (p<0.05)). However, these levels decreased to 151.88+/-17.02 (mesenteric ischemia) and 108.88+/-9.46 (peripheral ischennia) after 6 hours. The PON-I levels of Group III (mesenteric ischemia at 6 hours) (99.75+/-7.26), Group IV (peripheral ischemia at 2 hours) (96.88+/-4.09), and Group V (peripheral ischemia at 6 hours) (111.25+/-10.33) were slightly elevated over that of the control group (87.38+/-5.31). However, the PON-I level of Group 11 (mesenteric ischemia at 2 hours) (42.88+/-3.14) was lower than that of the other groups (p<0.05). Conclusion: Despite the increment of oxidative markers in early periods of ischemia (2nd hour), which was a hypoxic response of ischemic cells, they have decreased markedly in prolonged ischemia. This might have been caused by the opening of some collateral circulation or the destruction of the ischemic cells.