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Featured researches published by Gursel Cok.


Respiration | 2001

Pulmonary Tuberculosis in Patients with Diabetes mellitus

Feza Bacakoglu; Ozen K. Basoglu; Gursel Cok; Abdullah Sayiner; Mahmut Ateş

Background: Diabetes mellitus has been reported to modify the presenting features of pulmonary tuberculosis, but there are varying data, particularly regarding the association with lower lung field involvement. Objectives: To determine whether diabetes mellitus alters the clinical and radiographic manifestations of tuberculosis in nonimmunocompromised hosts and to define the determinants of lower lung field involvement. Methods: A retrospective review of the records of all patients with tuberculosis and diabetes mellitus seen during a 14-year period and of an age- and sex-matched nondiabetic control group with tuberculosis was carried out. The duration of symptoms, tuberculin reaction, bacteriologic and radiographic findings of the two groups were compared. Results: The presence of diabetes mellitus was found not to have an effect on patients’ symptomatology, bacteriology results, tuberculin reaction and localization of pulmonary infiltrates. On the other hand, fewer diabetic patients were smear-positive and fewer had reticulonodular opacities compared with the control patients. A higher number of insulin-dependent diabetic patients presented with cavitary disease as compared with nondiabetic controls. Lower lung field tuberculosis was significantly associated with female gender and, in patients older than 40 years, was more frequently observed in diabetics. Conclusion: These data show that diabetes does not affect the presenting features of pulmonary tuberculosis to a large extent and is only associated with lower lung field disease in older patients.


Clinical and Experimental Medicine | 2005

Effect of different levels of cigarette smoking on lipid peroxidation, glutathione enzymes and paraoxonase 1 activity in healthy people.

Z. A. Solak; Ceyda Kabaroglu; Gursel Cok; Zuhal Parildar; Ulku Bayindir; Dilek Özmen; Oya Bayindir

The purpose of this study was to examine the effect of different levels of cigarette smoking on lipid peroxidation, glutathione enzymes and paraoxonase 1 (PON1) activity in a healthy population. The study included 130 subjects who were classified as mild (≤10 cigarettes daily, Group I, n=30), moderate (11–20 cigarettes daily, Group II, n=35), heavy (>20 cigarettes daily, Group III, n=33) and never smokers (controls, Group IV, n=32). Malondialdehyde (MDA) levels, PON1 and erythrocyte glutathione enzyme activities were measured. MDA levels were significantly higher in smokers than never smokers (P<0.05 for Group I, P<0.001 for Group II and III). PON1 activity was significantly lower in heavy smokers (P<0.001). Glutathione peroxidase (GSH-Px) activity was significantly lower in the smokers (P<0.0001). Glutathione reductase (GR) activity was significantly higher in smokers (P<0.0001). MDA levels negatively correlated with PON1 and GSH-PX activities (P<0.01), whereas they positively correlated with GR activities (P<0.001). At every level, cigarette smoking is associated with increased lipid peroxidation and causes an impairment in antioxidant systems.


Cell Biology International | 2012

Cisplatin resistance induced by decreased apoptotic activity in non-small-cell lung cancer cell lines

Vildan Bozok Çetintaş; Ali Sahin Kucukaslan; Buket Kosova; Asli Tetik; Nur Selvi; Gursel Cok; Cumhur Gunduz; Zuhal Eroglu

We have investigated defective steps in apoptosis that might account for the development of resistance. For this purpose, A549 and Calu1 NSCLC (non‐small‐cell lung cancer) cell lines were treated with cisplatin to obtain resistant sub‐lines. Gene expression profiles and the phosphorylation status of the BAD (Bcl‐2/Bcl‐XL‐antagonist, causing cell death) protein were determined for each cell line. Cell death and cytochrome c release were analysed after treating cell lines with their appropriate cisplatin doses. Gene expression of BAD, Bid, caspases 4 and 6 were clearly decreased in the resistant cell lines, and the differential phosphorylation status of BAD also seemed to play a role in the development of cisplatin resistance. Since this is a new cisplatin‐resistant Calu1 cell line, it is noteworthy that DNA fragmentation, apoptotic cell ratio and cytochrome c levels were most decreased in the CR‐Calu1 cell line.


Annals of Nuclear Medicine | 2006

Tc-99m MIBI SPECT in prediction of prognosis in patients with small cell lung cancer

Aysegul Akgun; Gursel Cok; Inanc Karapolat; Tuncay Goksel; Zeynep Burak

PurposeThe purpose of this study was to evaluate whether the degree of technetium-99m methoxyisobutylisonitrile (MIBI) uptake and its retention in delayed imaging in small cell lung cancer (SCLC) was correlated with the response to multiagent chemotherapy and to investigate if there was a relationship between the survival time of patients with SCLC and Tc-99m MIBI SPECT tumor uptake parameters at the time of diagnosis.MethodsBetween 1998 and by December 2004, 40 patients with SCLC were studied with Tc-99m MIBI SPECT at the time of diagnosis. The patients were classified by a follow-up CT as good responders (complete or partial remission) and poor responders (stable disease or progressive disease). Following i.v. administration of 740 MBq Tc-99m MIBI, SPECT imaging at 30 minutes (early) and 2 hours (delayed) was performed. Regions of interests were placed over the tumors and contralateral normal lung tissue on one transverse section. The uptake ratio of the lesion to that in the contralateral normal lung was obtained from early images (early ratio; ER) as well as delayed images (delayed ratio; DR). The retention index (RI%) was measured as: RI% = [(DR - ER)/ER] x 100. Tc-99m MIBI tumor uptake parameters were compared with chemotherapeutic response and survival time.ResultsOf 40 patients, 29 patients were good responders (72.5%) and 11 patients were poor responders (27.5%). RI% of Tc-99m MIBI SPECT in the group of good response was significantly higher than in that with poor response (p < 0.05). On the other hand, there was no significant difference between the two groups with respect to ER or DR values. Four of 40 patients were still alive with disease (10%). The patient survival time varied from 1 to 70 months (mean survival time = 12.9 ± 13.4 months). There was no significant difference between the survival time of patients with respect to ER or DR of Tc-99m MIBI SPECT imaging. When median RI% was accepted as a cut-off value (-3.85%), patients with higher RI% values had a longer survival time (12 months) when compared with those with low RI% (8 months), p < 0.05.ConclusionOur results suggest that Tc-99m MIBI SPECT could accurately predict the chemotherapy response in patients with SCLC. RI% of Tc-99m MIBI SPECT is recommended to differentiate patients with a poor response to chemotherapy and good responders, and RI% of Tc-99m MIBI SPECT appears as the only parameter that may be useful in predicting the survival of patients with SCLC.


Environmental Research | 2003

Respiratory impairment due to asbestos exposure in brake-lining workers

Münevver Erdinç; Ertürk Erdinç; Gursel Cok; Mehmet Polatli

There is extensive evidence that exposure to asbestos causes pulmonary parenchymal fibrosis, pleural disease, and malignant neoplasm in asbestos-exposed workers. However, few data concerning brake-lining workers are available in the literature. In this study, we aimed to assess the long-term effects of chrysotile asbestos exposure on lung function and the risk of asbestos-related diseases in brake-lining workers. Seventy-four asbestos-exposed workers who processed brake-lining products and 12 unexposed office workers were offered pulmonary function tests (spirometry and transfer factor) in 1992 and 1999. In 1999, the mean duration of asbestos exposure was 10.00+/-4.07 and 11.02+/-4.81 years (7-31 years) in nonsmoking and smoking asbestos workers, respectively. Transfer factor (T(L), CO) and transfer coefficient (K(CO)) decline were significant in the 7-year follow-up in both smoking and nonsmoking asbestos workers. However, lung function indices of the control group, whom were all current smokers; were also found to be decreased, including FEF(75), T(L), CO and K(CO). We found minimal reticular changes in 10 asbestos workers who were all current smokers, they underwent high-resolution computed tomography scans of the chest and we found that they had peribronchial thickening resulting from smoking. As a conclusion, even in the absence of radiographic asbestosis, T(L), CO and K(CO) may decrease after a mean 10-year duration of exposure to asbestos in brake-lining workers and this is more noticeable with cigarette burden.


Academic Radiology | 2011

Predictors of Clinical Outcome in Acute Pulmonary Embolism: Correlation of CT Pulmonary Angiography with Clinical, Echocardiography and Laboratory Findings

Naim Ceylan; Sezai Tasbakan; Selen Bayraktaroglu; Gursel Cok; Tarik Simsek; Soner Duman; Recep Savas

RATIONALE AND OBJECTIVES The aims of this study were to retrospectively evaluate whether computed tomographic (CT) parameters were predictors of in-hospital mortality within 30 days of CT imaging and to compare CT parameters with clinical, echocardiographic, and laboratory findings in patients with acute pulmonary embolism (PE). MATERIALS AND METHODS A total of 122 patients (61 women, 61 men; mean age, 64 ± 15 years) with CT scans positive for acute PE were reviewed. Two independent readers who were blinded to clinical outcomes scored pulmonary artery obstructions, evaluated cardiovascular measurements, and assessed qualitative findings. Reports of echocardiographic, clinical, and laboratory findings and clinical outcome were reviewed. Results were correlated with patient outcomes using Wilcoxons rank-sum, χ², and Students t tests. Logistic regression analyses were performed to determine predictors of patient outcomes. RESULTS Thirteen patients (11%) died related to PE within 30 days in the hospital. There were significant differences in the ratio of arterial partial pressure of oxygen to inspired fraction of oxygen and in heart rate between survivors and nonsurvivors (P < .05). No CT or echocardiographic predictor was associated with mortality. CONCLUSIONS The ratio of arterial partial pressure of oxygen to inspired fraction of oxygen and heart rate strongly predicted mortality due to PE. Neither CT pulmonary angiographic variables nor echocardiography could successfully predict in-hospital mortality in patients with acute PE.


Thoracic and Cardiovascular Surgeon | 2011

Prognostic factors for survival in patients with thymic epithelial tumors.

Demirci S; Kutsal Turhan; Ozsan N; Yalman D; Alpaslan Çakan; Gursel Cok; Ufuk Çağırıcı; Ozkok S

BACKGROUND Aim of the study was to identify and evaluate the prognostic efficacy of standard clinicopathological factors of thymic epithelial tumors (TETs) for treatment-related outcomes. MATERIALS AND METHODS All patients treated between 1993-2008 at Ege University Faculty of Medicine Departments of Radiation Oncology and Thoracic Surgery were reviewed retrospectively. RESULTS Forty-seven patients with a median age of 51 (range: 24-72) were identified. Complete resection was performed in 23 (51.1%), incomplete resection with microscopic residues in 17 (37.8%), subtotal resection with gross residues in 2 (4.4%) and biopsy in 5 (11.1%) patients. Radiotherapy was administered to 39 (83%) patients. Median follow-up duration was 51 months (range: 3-168 months). Five-year local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS) rates were 93%, 90% and 85% for thymoma and 80%, 66% and 72% for thymic carcinoma patients, respectively. In multivariate analysis, the extent of resection was the only significant prognostic factor for OS (P = 0.001). CONCLUSIONS The most important prognostic factor for overall survival was the extent of resection. Further studies with larger numbers of patients are required to confirm the prognostic factors and to obtain a better understanding of the biological behavior of TETs.


International Journal of Radiation Oncology Biology Physics | 2010

Postoperative Radiotherapy in the Management of Resected Non–Small-Cell Lung Carcinoma: 10 Years' Experience in a Single Institute

Omur Karakoyun-Celik; Deniz Yalman; Yasemin Bolukbasi; Alpaslan Çakan; Gursel Cok; Serdar Ozkok

PURPOSE This study reports the long term outcomes of postoperative radiotherapy in patients with resection for non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS A total of 98 patients with resected NSCLC who received postoperative radiotherapy (PORT) between January 1994 and December 2004 were retrospectively analyzed. The most frequently performed surgical procedure was lobectomy (59 patients), followed by pneumonectomy (25), wedge resection (8), and bilobectomy (6). Postoperative radiotherapy was delivered as an adjuvant treatment in 71 patients, after a wedge resection in 8 patients, and after an R1 resection in 19 patients. The PORT was administered using a Co-60 source in 86 patients and 6-MV photons in 12 patients. A Kaplan-Meier estimate of overall survival, locoregional control, and distant metastasis-free survival were calculated. RESULTS Stages included I (n =13), II (n = 50), IIIA (n = 29), and IIIB (n = 6). After a median follow-up of 52 months median survival was 61 months. The 5-year overall survival, locoregional control, and distant metastasis-free survival rates for the whole group were 50%, 78%, and 55% respectively. The RT dose, Karnofsky performance status, age, lateralization of the tumor, and pneumonectomy were independent prognostic factors for OAS; anemia and the number of involved lymph nodes were independent prognostic factors for LC. CONCLUSIONS Doses of PORT of greater than 54 Gy were associated with higher death rate in patients with left-sided tumor, which may indicate a risk of radiation-induced cardiac mortality.


Thoracic and Cardiovascular Surgeon | 2010

The Effect of Blood Vessel Invasion on Prognosis of Operated Stage I Non-small Cell Lung Cancer Patients

Kutsal Turhan; Ozgur Samancilar; Ufuk Çağırıcı; Tuncay Goksel; Deniz Nart; Alpaslan Çakan; Gursel Cok

OBJECTIVE A retrospective study was conducted to identify the effect of blood vessel invasion on prognosis in surgically treated stage I non-small cell lung cancer patients. METHODS A total of 71 consecutive patients who had undergone complete resection for stage I primary non-small cell lung cancer (NSCLC) between 1998 and 2007 were evaluated. All pathological specimens were examined for evidence of blood vessel invasion. The follow-up period was 5-118 months. Survival data were analyzed for all patients using the Kaplan-Meier test. RESULTS There were 63 men and 8 women (mean age 59.2, age range 35-86). The most common tumor types were adenocarcinoma (35 patients, 49 %) and squamous cell carcinoma (26 patients, 37 %). Twenty-five patients (35 %) had stage IA disease, and 46 had (65 %) stage IB disease. In 13 cases (18 %) blood vessel invasion was demonstrated, whereas in the remaining 58 cases there was no evidence of vascular invasion. Minimum and maximum follow-up periods were 5 and 118 months respectively, with a mean of 41.76 +/- 27 months (median 33.5 months). Overall disease-free survival was 79.6 +/- 6.4 months: 38.3 +/- 12.0 months for the group with blood vessel invasion and 87.5 +/- 6.7 months for the remaining group. The difference between the two groups was statistically significant ( P < 0.003). Overall survival rate was 86.7 +/- 6.7 months: 44.5 +/- 11.3 months for blood vessel invasion group and 98.2 +/- 6.2 months for the remaining group. The difference between the two groups was statistically significant ( P < 0.001). CONCLUSION Vascular invasion can be an important factor for predicting unfavorable prognosis in stage I NSCLC patients.


Turkish Journal of Medical Sciences | 2016

The role of apelin in the assessment of response to chemotherapyand prognosis in stage 4 nonsmall cell lung cancer

Sinem Ermin; Gursel Cok; Ali Veral; Timur Köse

BACKGROUND/AIM Prediction of response to chemotherapy and prognosis bears clinical significance in patients with lung cancer. The aim of the study was to examine the association between apelin expression in tumor tissues and overall survival, progression-free survival, chemoresistance, and treatment response in stage 4 nonsmall cell lung cancer (NSCLC) patients undergoing chemotherapy. MATERIALS AND METHODS A total of 81 patients who received chemotherapy due to a biopsy-documented diagnosis of NSCLC between 2004 and 2011 were retrospectively studied. Bronchoscopic biopsy samples were examined immunohistochemically. RESULTS Of the overall study population (n = 81), the mean age was 59.0 ± 9.2 years; 83% (n = 67) were male and 17% (n = 14) were female. All patients received chemotherapy. A total of 30 patients (37%) had no apelin positivity, while 21 (30%) had 1 +, 20 (25%) had 2 +, and 10 (12%) had 3 + apelin positivity. We detected no association between apelin positivity and overall survival, 6-month survival, or 1-year survival rates (P = 0.05, 0.74, and 0.63). Patients with apelin expression as compared to those without it had shorter overall survival (P = 0.05). CONCLUSION Our results suggest that apelin, an angiogenic factor, does not seem to provide significant prognostic information in this patient group.

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