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Dive into the research topics where Mehmet Tokaç is active.

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Featured researches published by Mehmet Tokaç.


Mediators of Inflammation | 2003

Levels of serum IL-1beta, IL-2, IL-8 and tumor necrosis factor-alpha in patients with unstable angina pectoris.

Ali Özeren; Mustafa Aydin; Mehmet Tokaç; Nejat Demircan; Murat Unalacak; Ahmet Gurel; Mehmet Yazici

OBJECTIVES Inflammation is the most important mechanism of plaque disruption playing an essential role in acute coronary syndromes. It is controversial whether the inflammatory mediators are the cause or the result in the development of plaque rupture. Stimulation of interleukins increases adhesion molecules, fibrinogen and plasminogen activator inhibitors,which cause the activation of inflammation and thrombosis. However, the importance of interleukins in acute coronary syndromes has not been clearly defined. We did not find any article concerning relations between the levels of serum interleukin(IL)-1beta, IL-2, IL -8 and tumor necrosis factor (TNF)-alpha in patients with unstable angina pectoris (UAP). So the aim of this study was to determine the levels of serum I -1b, IL-2, IL-8 and TNF-alpha during the early stage of UAP. METHODS AND RESULTS Thirty-seven patients with UAP(12 females and 25 males; mean age, 57.5 +/- 9.7 years) within 6 h of admission and 20 healthy volunteers(eight females and 12 males; mean age, 51.3 +/- 6.3 years) were included in the study. IL-1beta, IL-2, IL-8 and TNF-alpha levels were measured using the enzyme-linked immunosorbent assay method. Patients with acute or chronic inflammation, renal failure or chronic heart failure were excluded from the study. The age, gender and risk factors of the study and control groups were similar. The levels of IL-1beta, IL-8 and TNF-alpha were significantly increased (p < /0.0001, p < /0.001 and p < /0.016, respectively) in patients with UAP. There was no difference of IL-2 levels between the UAP group and controls. CONCLUSION We detected high levels of IL-1beta, IL-8 and TNF-alpha in patients with UAP during early phase. We suggest that proinflammatory cytokines (e.g. IL-1beta,IL-8, TNF-alpha) may play an important role in the development of atherosclerosis and its complications.


Food and Chemical Toxicology | 2013

Protective effects of curcumin against oxidative stress parameters and DNA damage in the livers and kidneys of rats with biliary obstruction

Mehmet Tokaç; Gökçe Taner; Sevtap Aydın; Halit Ziya Dündar; Mine Yavuz Taşlıpınar; Ata Türker Arıkök; Mehmet Kılıç; A. Ahmet Başaran; Nurşen Başaran

Curcumin, a most active antioxidant compound, has been suggested to have potential beneficial effects against most metabolic and psychological disorders, including cholestasis. In the present study, the effects of curcumin against oxidative stress and DNA damage induced by bile duct ligation (BDL) in Wistar albino rats for 14 days were investigated. The rats were divided into three following groups: Sham group, the BDL group and the BDL+curcumin group. A daily dose of 50mg/kg curcumin was given to the BDL+curcumin group intragastrically for 14 days. The biomarkers of hepatocellular damage were decreased in the BDL+curcumin group compared to the BDL group, indicating that curcumin recovered the liver functions. DNA damage as assessed by the alkaline comet assay was also found to be low in the BDL+curcumin group. Curcumin significantly reduced malondialdehyde and nitric oxide levels, and enchanced reduced glutathione levels and catalase, superoxide dismutase, and glutathione S-transferase enzymes activities in the livers and kidneys of BDL group. Curcumin treatment in BDL group was found to decrease tumor necrosis factor-alpha levels in the livers of rats. These results suggest that curcumin might have protective effects on the cholestasis-induced injuries in the liver and kidney tissues of rats.


Journal of Electrocardiology | 2008

Value of lead aVR in predicting acute occlusion of proximal left anterior descending coronary artery and in-hospital outcome in ST-elevation myocardial infarction: an electrocardiographic predictor of poor prognosis

Nazif Aygul; Kurtulus Ozdemir; Mehmet Tokaç; Meryem Ulku Aygul; Mehmet Akif Duzenli; Adnan Abaci; Ahmet Bacaksiz; Hüseyin Uğur Yazıcı; Sait Bodur

BACKGROUND We aimed to investigate the value of ST elevation in lead aVR (ST upward arrow aVR) in predicting the left anterior descending coronary artery (LAD) occlusion site proximal to first septal perforator (S(1)) and its effect on in-hospital outcome in ST-elevation myocardial infarction (STEMI). METHODS The study included 950 patients with STEMI. Patients were divided into 2 groups as aVR(+) and aVR(-) according to the presence of an ST upward arrow aVR of 0.5 mm or greater. RESULTS ST elevation in lead aVR was seen in 155 (16%) patients, and LAD occlusion proximal to S(1) was detected in 52% of patients in the aVR(+) group and in 9% of patients in the aVR(-) group. aVR positivity was associated with higher heart rate, lower systolic blood pressure and ejection fraction, and worse Killip class at the hospital admission. In-hospital mortality was 19% in the aVR(+) group and 5% in the aVR(-) group. aVR positivity was an independent predictor of in-hospital death. CONCLUSION This study revealed that ST upward arrow aVR was not only a good indicator of LAD occlusion proximal to S(1) but also a source of valuable information about in-hospital outcome in patients with STEMI.


BMC Surgery | 2014

Management of idiopathic granulomatous mastitis: dilemmas in diagnosis and treatment

Gulten Kiyak; Ersin Gürkan Dumlu; İbrahim Kılınç; Mehmet Tokaç; Soner Akbaba; Ahmet Gürer; Mehmet Kılıç

BackgroundIdiopathic granulomatous mastitis (IGM) is a rare inflammatory disease.Because of it’s uncommon etiology and rareness, diagnosis and treatment is still a challenge. Owing to wide spectrum of IGM it is difficult to standardize and optimize the treatment. The aim of this study was to report and describe the clinical signs, radiological findings, management, clinical course and the recurrence rate of the patients which were treated due to IGM.MethodsIn this retrospective review of patients diagnosed with IGM histopathologically between January 2006 and December 2011, medical reports, ultrasonography (US) and mammograhy (MMG) findings, follow-up information and recurrence were obtained from records.ResultsPainful, firm and ill defined mass was the symptom of all patients. While parenchymal heterogeneity, abscess and mass were the findings of US, increased asymmetric density was the main finding of MMG. Wide local excision was performed in 15 (62.5%) patients, incisional biopsy with abscess drainage was performed in 9 (37.5%) patients. Median follow-up was 34.8 (range 10–66) months.ConclusionsWhile the physical examination give rise to thought of breast carcinoma, the appearance of parenchymal heterogeneity and abscess formation on US especially with enlarged axillary lymph nodes support the presence of an inflammatory process. But these findings do not exclude carcinoma. Hereby, histopathologic confirmation is mandatory to ensure that a malignancy is not missed.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2009

The Effect of Nondipping Blood Pressure Patterns on Cardiac Structural Changes and Left Ventricular Diastolic Functions in Normotensives

Ahmet Soylu; Mehmet Akif Duzenli; Mehmet Yazici; Kurtulus Ozdemir; Mehmet Tokaç; Hasan Gök

Background: Cardiac structural changes have been reported to be more prominent in nondipper normotensives than the dipper ones. But the influence of nondipping status on cardiac diastolic functions of normotensives has not been studied yet. In this study, we investigated the effect of nondipping status on both cardiac structural changes and left ventricular (LV) diastolic functions in normotensives. Methods: We performed ambulatory blood pressure (BP) monitoring (ABPM) and echocardiography in 62 normotensive subjects with the following criteria: (1) office BP < 140/90 mmHg; (2) average 24‐hour ambulatory BP < 130/80 mmHg. Results: In the evaluation by tissue Doppler imaging (TDI), the early diastolic myocardial peak velocity (Em) and Em/late diastolic myocardial peak velocity (Am) ratio (Em/Am ratio) were lower in nondippers than those in dippers (P = 0.009 and P < 0.001, respectively). Isovolumic relaxation time (IRT) and myocardial performance index (MPI) were higher in nondippers than those in dippers (P = 0.036 and P = 0.026, respectively). Nondipping status, independent of other factors, was observed to cause both a decrease in the Em and Em/Am ratio and an increase in IRT. However, its effect on IRT was not statistically significant (coefficient =−0.27, P = 0.027; coefficient =−0.37, P = 0.002; coefficient = 0.20, P = 0.082, respectively). Conclusions: Nondipping of nocturnal BP seems to be a determinant of cardiac remodeling and LV diastolic dysfunction (LVDD) and may result in a cardiovascular (CV) risk independent of the increase in LV mass (LVM) in normotensives.


Heart and Vessels | 2003

The role of inflammation markers in triggering acute coronary events

Mehmet Tokaç; Ali Özeren; Murad Aktan; Bülent Behlül Altunkeser; KurtuluŞ Özdemir; Akif Düzenli; Hasan Gök

Studies have shown disparate results in relation to the role of plasma concentrations of inflammation markers such as fibrinogen, cytokines, and cell adhesion molecules in acute coronary syndromes. The differentiation of primary versus secondary alterations of these markers in response to acute coronary syndromes is not clear. The aim of this study was to investigate the effect of soluble cell adhesion molecules and some inflammatory markers on coronary plaque instability. The prospective study consisted of 15 patients with stable angina pectoris (SAP), 16 with unstable angina pectoris (UAP), and 16 who had undergone percutaneous transluminal coronary angioplasty (PTCA). Blood samples were obtained from the SAP group on admission, from the UAP group at the early stage of pain onset within 6 h of pain, and again after 12 h of pain. Samples from the PTCA group were collected before, 2, 14 h after the procedure. Soluble vascular cell adhesion molecule-1 (VCAM-1), endothelial selectin, interleukin-1Β (IL-1Β) and interleukin-2 (IL-2), and C-reactive protein (CRP) were analyzed by enzyme-linked immunosorbent assay. CRP serum levels gradually increased although IL-2 gradually decreased in patients with UAP and PTCA. In addition, VCAM-1 levels were sharply decreased after the PTCA procedure. However, this value returned back to the preprocedure levels 14 h after PTCA. Both CRP and IL-2 are directly involved in the triggering mechanisms of acute coronary events.


Journal of Electrocardiology | 2009

Type II bidirectional ventricular tachycardia in a patient with myocardial infarction

Osman Sonmez; Enes Elvin Gul; Cetin Duman; Mehmet Akif Duzenli; Mehmet Tokaç; Jonni Cooper

A 84-year-old man presented to the emergency department complaining of chest pain and palpitations. He had no history of coronary artery disease. The 12-lead electrocardiography showed bidirectional ventricular tachycardia (BVT). Coronary angiography revealed severe mid left anterior descending and mid left circumflex lesions. The BVT, in this case, was most likely due to myocardial ischema. The ethiology of published BVT cases are most commonly digitalis toxicity and rarely herbal aconitine poisoning, hypokalemic periodic paralysis, cathecolaminergic VT, myocarditis, and Anderson-Tawil syndrome. The patient had neither of these underlying conditions. To the best of our knowledge and research in the literature, there was no report of bidirectional VT in the patients with myocardial infarction.


International Surgery | 2014

Early versus delayed laparoscopic cholecystectomy for acute cholecystitis: a prospective, randomized study.

Mehmet Tokaç; Ersin Gürkan Dumlu; Birkan Bozkurt; Ahmet Çiftci; Fahri Yetişir; Mehmet Kılıç

We aimed to compare the clinical outcome and cost of early versus delayed laparoscopic cholecystectomy for acute cholecystitis. Sixty patients with acute cholecystitis were randomized into early (within 24 hours of admission) or delayed (after 6-8 weeks of conservative treatment) laparoscopic cholecystectomy groups. There was no significant difference between study groups in terms of operation time and rates for conversion to open cholecystectomy. On the other hand, total hospital stay was longer (5.2 ± 1.40 versus 7.8 ± 1.65 days; P = 0.04) and total costs were higher (2500.97 ± 755.265 versus 3713.47 ± 517.331 Turkish Lira; P = 0.03) in the delayed laparoscopic cholecystectomy group. Intraoperative and postoperative complications were recorded in 8 patients in the early laparoscopic cholecystectomy group, whereas no complications occurred in the delayed laparoscopic cholecystectomy group (P = 0.002). Despite intraoperative and postoperative complications being associated more with early laparoscopic cholecystectomy compared with delayed intervention, early laparoscopic cholecystectomy should be preferred for treatment of acute cholecystitis because of its advantages of shorter hospital stay and lower cost.


American Journal of Cardiology | 2008

Comparison of increased aspirin dose versus combined aspirin plus clopidogrel therapy in patients with diabetes mellitus and coronary heart disease and impaired antiplatelet response to low-dose aspirin.

Mehmet Akif Duzenli; Kurtulus Ozdemir; Nazif Aygul; Ahmet Soylu; Mehmet Tokaç

The effects of therapy with aspirin 300 mg/day and with combined aspirin 100 mg/day plus clopidogrel 75 mg/day on platelet function were compared in patients with diabetes mellitus and coronary artery disease and impaired antiplatelet responses to aspirin 100 mg/day. The study population consisted of 151 outpatients with type II diabetes mellitus and coronary artery disease who were taking aspirin 100 mg/day. Of the 151 patients, a subgroup of subjects with impaired aspirin response were selected on the basis of the results of platelet aggregometry. Nonresponsiveness to aspirin was defined as mean aggregation > or =69% with 3 micromol/L adenosine diphosphate and mean aggregation > or =70% with 2 micromol/L collagen. Aspirin semiresponders were defined as meeting 1 but not both of these criteria. Nonresponders and semiresponders were randomized equally to aspirin 300 mg/day and aspirin 100 mg/day plus clopidogrel 75 mg/day, and aggregation tests were repeated after 2 weeks. Sixty of the 151 patients with diabetes (40%) were found to respond to aspirin inadequately. Platelet aggregation induced by adenosine diphosphate and collagen decreased significantly after aspirin 300 mg/day or combined therapy. Combined treatment was found to have a stronger inhibitory effect on platelet aggregation induced by adenosine diphosphate than aspirin 300 mg/day (p = 0.002). Impaired aspirin response was resolved by increasing the aspirin dose or adding clopidogrel to aspirin (p <0.0001 for each). However, desired platelet inhibition was achieved in significantly more patients by combined treatment than by aspirin 300 mg/day (p <0.05). In conclusion, aspirin 100 mg/day does not inhibit platelet function adequately in a significant number of patients with diabetes mellitus and coronary artery disease. Increasing the aspirin dose to 300 mg/day or adding clopidogrel to aspirin can provide adequate platelet inhibition in a significant number of those patients with impaired responses to low-dose aspirin.


International Surgery | 2015

Comparison of modified Limberg flap and Karydakis flap operations in pilonidal sinus surgery: prospective randomized study.

Mehmet Tokaç; Ersin Gürkan Dumlu; Murat Seyit Aydin; Abdussamed Yalcin; Mehmet Kılıç

The best surgical technique for pilonidal sinus disease (PSD) is still disputed. The objective of this prospective randomized study is to compare the short and long-term results of modified Limberg flap and Karydakis flap surgeries that have been widely used in recent years. Ninety one patients were included in the study. The patients were divided into two groups: modified Limberg flap (MLF; n = 46) and Karydakis flap (KF; n = 45). Preoperative findings of the patients, their surgical findings, and short and long-term postoperative findings were recorded and statistically compared. While no significant difference was discovered between the groups in terms of postoperative analgesic need, hospital stay, postoperative infection rate, drain stay time, painless sitting time, painless toilet-sitting time, and painless walking time, return to work or school time was shorter in the MLF group compared with the KF group (20.61 ± 7.89 days, 23.29 ± 6.42, respectively; P < 0.05). Cosmetically, the visual analog scale (VAS) of the KF group was significantly higher than that of the MLF group (VAS score 7.12 ± 1.28, 5.45 ± 1.77, respectively; P < 0.05). Considering recurrence rates, no statistically significant difference was found between the groups. Our study found out that short and long-term results of the MLF and KF procedures are similar. We believe both methods can be safely used in surgical PSD treatment given that in the MLF procedure, shorter return-to-work time is achieved, while the procedure provides better cosmetic results.

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Ersin Gürkan Dumlu

Yıldırım Beyazıt University

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Mehmet Kılıç

Yıldırım Beyazıt University

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Abdussamed Yalcin

Yıldırım Beyazıt University

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