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Browsing by Author "Kostek, Osman"

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    Coronary Flow Velocity Reserve in Burn Injury: A Prospective Clinical Cohort Study
    (2016) Caliskan, Mustafa; Turk, Emin; Karagulle, Erdal; Ciftci, Ozgur; Oguz, Hakan; Kostek, Osman; Moray, Gokhan; Haberal, Mehmet; 0000-0002-3462-7632; 0000-0003-2498-7287; 0000-0002-8522-4956; 0000-0002-1901-5603; 0000-0003-4766-3373; 26284645; AAJ-8097-2021; AAE-1041-2021; C-6247-2017; AAA-3604-2019; AAJ-5609-2021
    The authors sought to evaluate coronary microvascular function and left ventricular diastolic dysfunction using transthoracic Doppler echocardiography in burn patients. In this study, 32 adult burn patients with partial or full-thickness scald burns that were hospitalized and treated were included. The control group was matched for age and sex and was composed of otherwise healthy volunteers. Transthoracic Doppler echocardiography examinations and simultaneous laboratory tests for cardiac evaluation were performed on the sixth month after burn injury as well as with the control group. High-sensitivity C-reactive protein levels were significantly higher in the burn patients than in controls (5.17 +/- 3.86 vs 2.42 +/- 1.78; P =.001). Lateral isovolumic relaxation time was significantly higher in the burn injury group than in the control group (92.7 +/- 15.7 vs 85.5 +/- 8.3; P =.03). Baseline coronary diastolic peak flow velocity of the left anterior descending artery was similar in both groups. However, hyperemic diastolic peak flow velocity and coronary flow velocity reserve (2.26 +/- 0.48 vs 2.94 +/- 0.47; P <.001) were significantly lower in the burn injury group than in the control group. Coronary flow velocity reserve was significantly and inversely correlated with high-sensitivity C-reactive protein, burn ratio, creatinine, and mitral A-wave max velocity. At the sixth month of treatment, burn patients had high-sensitivity C-reactive protein levels during this period, suggesting that inflammation still exists. In addition, subclinical coronary microvascular and left ventricular diastolic dysfunction can occur in burn patients without traditional cardiovascular risk factors. However, these results must be supported by additional studies.
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    Cystatin-C and TGF-beta levels in patients with diabetic nephropathy
    (2016) Takir, Mumtaz; Unal, Asli Dogruk; Kostek, Osman; Bayraktar, Nilufer; Demirag, Nilgun Guvener; 0000-0002-7886-3688; 27745866; Y-8758-2018
    Objective: To evaluate renal impairment in type 2 diabetic patients with normoalbuminuria or microalbuminuria by detection of serum cystatin C and serum and urinary TGF-beta levels. Methods: Cross-sectional study conducted at the Department of Endocrinology in Baskent University School of Medicine. Patients with type 2 diabetes mellitus without known overt diabetic nephropathy were included in the study. Recruited patients were stratified into four groups, matched in terms of age, gender, microalbuminuria level and estimated GFR calculated with MDRD. Results: 78 patients were enrolled. They were categorized into four groups depending on their urinary albumin excretion and estimated glomerular filtration rate. Macrovascular complication was found to be higher in patients with microalbuminuria than in other patients (p < 0.01), but there were no differences in terms of other diabetic complications. Serum cystatin C level was significantly higher in normoalbuminuric group one patients, while serum and urinary TGF-beta 1 levels were higher in microalbuminuric group two patients. The serum level of cystatin C was found to negatively correlate with eGFR in group two patients (r = -0.892, p < 0.001). Finally, there was a negative correlation between eGFR and cystatin C in all the patient groups (r = -0.726, p=0.001). Conclusions: Although urinary albumin excretion is recommended for the detection of type two diabetic nephropathy, there is a group of patients with decreased eGFR but without increased urinary albumin excretion, in which serum cystatin C level was indicated to be used as an early biomarker of diabetic nephropathy. (C) 2016 Published by Elsevier Espana, S.L.U. on behalf of Sociedad Espanola de Nefrologia.
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    Increased Morning Blood Pressure Surge and Coronary Microvascular Dysfunction in Patient with Early Stage Hypertension
    (2014) Caliskan, Mustafa; Caliskan, Zuhal; Gullu, Hakan; Keles, Nursen; Bulur, Serkan; Turan, Yasar; Kostek, Osman; Ciftci, Ozgur; Guven, Aytekin; Aung, Soe Moe; Muderrisoglu, Haldun; https://orcid.org/0000-0003-2579-9755; https://orcid.org/0000-0002-6463-6070; https://orcid.org/0000-0002-9635-6313; 25224866; IXD-5147-2023; A-7318-2017; AAJ-8546-2021; AAG-8233-2020
    Morning blood pressure surge (MBPS) is defined as an excessive increase in blood pressure (BP) in the morning from the lowest systolic BP during sleep, and it has been reported as a risk factor for cardiovascular events in current clinical studies. In this study, we evaluated the association between the rate of BP variation derived from ambulatory BP monitoring data analysis and coronary microvascular function in patients with early stage hypertension. One hundred seventy patients with prehypertension and Stage 1 hypertension who fulfilled the inclusion and exclusion criteria were included in the study. We divided our study population into two subgroups according to the median value of coronary flow reserve (CFR). Patients with CFR values <2.5 were defined as the impaired CFR group, and patients with CFR values >= 2.5 were defined as the preserved CFR group, and we compared the MBPS measurements of these two subgroups. CFR was measured using transthoracic Doppler echocardiography (TTDE). Ambulatory 24-hour systolic and diastolic BP, uric acid, systolic MBPS amplitude, diastolic MBPS amplitude, high-sensitivity C-reactive protein, and mitral flow E/A ratio were statistically significant. These predictors were included in age- and gender-adjusted multivariate analysis; ambulatory 24-hour systolic BP (beta = 0.077, P <.001; odds ratio [OR] = 1.080; 95% confidence interval [CI] [1.037-1.1241) and systolic MBPS amplitude (beta = 0.043, P =.022; OR = 1.044; 95% CI [1.006-1.0841) were determined to be independent predictors of impaired CFR (Hosmer-Lemeshow test, P=.165, Nagelkerke's R-2 = 0.320). We found that increased changes in MBPS values in patients with prehypertension and Stage 1 hypertension seemed to cause microvascular dysfunction in the absence of obstructive coronary artery disease. (C) 2014 American Society of Hypertension. All rights reserved.
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    The Influence of On-pump Versus Off-pump Surgery on Short- and Medium-term Postoperative Coronary Flow Reserve After Coronary Artery Bypass Grafting
    (2016) Ozulku, Mehmet; Caliskan, Mustafa; Saba, Tonguc; Aksu, Feyza; Ciftci, Ozgur; Gullu, Hakan; Guven, Aytekin; Kostek, Osman; Caklili, Ozge Telci; Aslamaci, Sait; 0000-0001-7566-5427; 0000-0002-9635-6313; 0000-0002-1901-5603; 27269474; AAT-7733-2020; AAG-8233-2020; AAA-3604-2019; AAJ-8546-2021
    Background Although several clinical trials have compared surgical outcomes between off-pump and on-pump coronary artery bypass grafting (CABG), whether there is a difference in the early- and medium-term postoperative coronary microvascular functions is not fully understood. We compared short- and medium-term coronary microvascular function after off-pump and on-pump CABG. Methods A prospective study of patients undergoing off-pump and on-pump CABG. Eighty-two patients scheduled for CABG were recruited: 38 underwent off-pump surgery and 44 on-pump surgery. Each participant's coronary flow reserve (CFR) and diastolic function were measured with transthoracic Doppler echocardiography six and 12 months after surgery. Results Baseline and hyperaemic diastolic peak flow velocity in the left anterior descending artery were similar in both groups, as was CFR (2.22 +/- 0.66) in the off-pump group compared with (2.13 +/- 0.61) in the on-pump group, (P = 0.54). Coronary flow reserve was significantly and inversely correlated with high sensitivity C-reactive protein concentration (r = -0.416; P < 0.001) and positively correlated with mitral E/ A-wave velocity ratio (r = 0.247; P = 0.02). Stepwise linear regression analysis revealed that only high sensitivity C-reactive protein concentration was independently correlated with CFR (beta = -0.272, P = 0.02). Conclusions Heart-lung bypass technique had no medium-term influence on the coronary microcirculation, despite a possible initial unfavourable effect. Serum hs-CRP concentration was an independent predictor of medium-term coronary microvascular dysfunction.
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    Is Activation in Inflammatory Bowel Diseases Associated with Further Impairment of Coronary Microcirculation?
    (2016) Caliskan, Zuhal; Keles, Nursen; Gokturk, Huseyin Savas; Ozdil, Kamil; Aksu, Feyza; Ozturk, Oguzhan; Kahraman, Resul; Kostek, Osman; Tekin, Ahmet S.; Ozgur, Gulsum Teke; 27541650
    Background: Inflammatory bowel disease [IBD] includes a number of chronic relapsing diseases. In IBD intestinal microvascular endothelial cells are damaged by an abnormal immune response. Several studies have shown that IBD may cause increment in risk of developing atherosclerosis. IBD in activation was related to enhanced risks of worse cardiovascular [CV] outcome, on the other hand no risk increment was seen in remission comparing to control group in those studies. Coronary FlowReserve [CFR] reflects coronary microvascular circulation. Coronary microvascular dysfunction may be defined as a predictor of CV outcome combined with previous described atherosclerotic risk factors. The present study was purposed to further evaluate whether or not CFR in the left anterior descending artery [LAD] is disturbed in IBD patients with activation in comparison to remission and healthy subjects. Methods: 62 patients with IBD and 39 healthy volunteers were enrolled into the study. Patients' demographics were recorded. CFR evaluation of patients with IBD in both activation and remission period and control group were performed with transthoracic echocardiography. Results: CFR was significantly lowest in the active period of the IBD [2.26 [2.08-2.55] vs. 2.55 [2.18-3.00] and 3.10 [2.85-3.29] p < 0.001]. CFR is negatively correlated with disease activity scores of IBD. Conclusion: This study showed that CFR is more prominently disturbed in patients with IBD in activation. The activation of disease may have a major role in the progression of coronary microcirculatory dysfunction and future cardiovascular events. (C) 2016 Elsevier Ireland Ltd. All rights reserved.
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    Morning Blood Pressure Surge Is Associated with Carotid Intima-Media Thickness in Prehypertensive Patients
    (2017) Alpaydin, Sertac; Turan, Yasar; Caliskan, Mustafa; Caliskan, Zuhal; Aksu, Feyza; Ozyildirim, Serhan; Buyukterzi, Zafer; Kostek, Osman; Muderrisoglu, Haldun; https://orcid.org/0000-0002-9635-6313; 28272109; AAG-8233-2020
    Objective Morning blood pressure (BP) surge (MBPS) is defined as an excessive increase in the morning BP from the lowest systolic BP during sleep and is reported as a risk factor for cardiovascular events in current clinical studies. In this study, we aimed to investigate the relationship between MBPS and carotid intima-media thickness (C-IMT) in prehypertensive patients. Patients and methods We evaluated the association between the rate of BP variation derived from ambulatory BP monitoring and C-IMT in patients with prehypertension. Results One hundred and seventy patients with prehypertension were included in the study. All office BP measurements and ambulatory 24-h, day-time, and night-time measurements were similar between each group. C-IMT [0.60 (range: 0.57-0.65) vs. 0.55 (range: 0.50-0.60) cm; P < 0.001] and the mean platelet volume [8.7 (range: 7.9-9.1) vs. 7.9 (range: 7.3-8.8) fl; P = 0.002] were significantly higher in the greater MBPS group than the lower group. In multivariate analysis, male sex [odds ratio (OR): 2.271, confidence interval (CI): 1.011-5.100, P = 0.047], greater MBPS (OR: 8.474, CI: 3.623-19.608, P < 0.001), and elevated mean platelet volume levels (OR: 3.359, CI: 1.978-5.705, P < 0.001) were found to be independent predictors of greater C-IMT in prehypertensive patients. Conclusion Our study suggests that greater MBPS is associated independently with C-IMT in prehypertensive patients. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.
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    Previous Gestational Diabetes History is Associated with Impaired Coronary Flow Reserve
    (2015) Caliskan, Mustafa; Turan, Yasar; Caliskan, Zuhal; Gullu, Hakan; Ciftci, Faika Ceylan; Avci, Enver; Duran, Cevdet; Kostek, Osman; Caklili, Ozge Telci; Koca, Harun; Kulaksizoglu, Mustafa; 0000-0003-2579-9755; 26555575; IXD-5147-2023
    Background Gestational diabetes mellitus (GDM) is a prediabetic state that is known to increase the risk of cardiovascular diseases. We have investigated coronary flow velocity reserve (CFVR) and epicardial fat thickness (EFT), and left ventricular diastolic function in patients with a history of previous GDM (p-GDM). Methods Ninety-three women with GDM history and 95 healthy women without GDM history were recruited. We used transthoracic Doppler echocardiography to assess CFVR, EFT, and left ventricular diastolic function. Insulin resistance of each subject was assessed with homeostasis model assessment insulin resistance (HOMA-IR). Hemoglobin A1c and high-sensitivity C-reactive protein (hsCRP) were also measured in all patients. Results CFVR values were significantly lower (2.34 +/- 0.39 versus 2.80 +/- 0.24, p<0.001) and EFT values were significantly higher in patients with p-GDM than the control group (5.5 +/- 1.3 versus 4.3 +/- 1.1, p<0.001). E/E' ratio (7.21 +/- 1.77 versus 6.53 +/- 1.38, p = 0.003), hemoglobin A1c (5.2 +/- 0.4 and 5.0 +/- 0.3, p = 0.001), HOMA-IR (2.8 +/- 1.4 versus 1.7 +/- 0.9, p = 0.04), and hsCRP levels were significantly higher in the p-GDM group than the control group. Multivariate analysis revealed that gestational diabetes history is independently associated with CFVR. Conclusion Women with a GDM history may be at more risk regarding coronary microvascular dysfunction compared to the healthy ones.
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    The relation of presenting symptoms with staging, grading, and postoperative 3-year mortality in patients with stage I-III non-metastatic colon cancer
    (2016) Bedir, Osman; Kiziltas, Safak; Kostek, Osman; Ozkanli, Seyma; 27210779
    Background/Aims: To evaluate the association of presenting symptoms with staging, grading, and postoperative 3-year mortality in patients with colon cancer. Materials and Methods: A total of 132 patients-with a mean (standard deviation; SD) age of 63.0 (10.0) years and of whom 56.0% were males-with non-metastatic stage I-III colon cancer were included. Symptoms prior to diagnosis were evaluated with respect to tumor localization, tumor node metastasis (TNM) stage, histological grade, and postoperative 3-year mortality. Results: Constipation and abdominal pain were the two most common symptoms appearing first (29.5% and 16.7%, respectively) and remained most predominant (25.0% and 20.0%, respectively) up to diagnosis. The frequency of admission symptoms significantly differed with respect to tumor location, TNM stage and histological grade. The postoperative 3-year survival rate was 61.4%. Multivariate logistic regression revealed that melena and rectal bleeding increased the likelihood of 3-year mortality by 13.6-fold (p=0.001) and 4.08-fold (p=0.011), respectively. Conclusion: Our findings revealed differences in presenting symptom profiles with respect to the time of manifestation and predominance as well as to the TNM stage, histological grade, and tumor location. Given that melena and rectal bleeding increased the 3-year mortality risk by 13.6-fold and 4.08-fold, respectively, our findings indicate the association of admission symptoms with outcome among patients with colon cancer.

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