Yaşar Tuna
Akdeniz University
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Featured researches published by Yaşar Tuna.
Clinical Gastroenterology and Hepatology | 2013
Seyfettin Köklü; Yaşar Tuna; Murat Taner Gulsen; Mehmet Demir; Aydın Şeref Köksal; Muhammet Cem Koçkar; Cem Aygun; Şahin Çoban; Kamil Özdil; Huseyin Ataseven; Ebru Akin; Tugrul Purnak; İlhami Yüksel; Hilmi Ataseven; Mehmet Ibis; Beytullah Yildirim; Isilay Nadir; Metin Kucukazman; Erdem Akbal; Osman Yüksel; Omer Basar; Erhan Alkan; Ozlem Baykal
BACKGROUND & AIMS Data are limited on the efficacy and safety of tenofovir and entecavir when given for more than 1 year to patients with hepatitis B-related cirrhosis. We investigated the long-term safety and efficacy of these antiviral drugs in patients with chronic hepatitis B virus (HBV) infection, with compensated or decompensated cirrhosis, and compared results with those from lamivudine. METHODS We performed a retrospective analysis of data from 227 adult patients with chronic HBV infection who were diagnosed with cirrhosis, beginning in 2005, at 18 centers throughout Turkey. There were 104 patients who had decompensated cirrhosis, and 197 patients were treatment naive before. Seventy-two patients received tenofovir (followed up for 21.4 ± 9.7 mo), 77 patients received entecavir (followed up for 24.0 ± 13.3 mo), and 74 patients received lamivudine (followed up for 36.5 ± 24.1 mo). We collected data on patient demographics and baseline characteristics. Laboratory test results, clinical outcomes, and drug-related adverse events were compared among groups. RESULTS Levels of HBV DNA less than 400 copies/mL were achieved in 91.5%, 92.5%, and 77% of patients receiving tenofovir, entecavir, or lamivudine, respectively. Levels of alanine aminotransferase normalized in 86.8%, 92.1%, and 71.8% of patients who received tenofovir, entecavir, and lamivudine, respectively. Child-Turcotte-Pugh scores increased among 8.5% of patients who received tenofovir, 15.6% who received entecavir, and 27.4% who received lamivudine. Frequencies of complications from cirrhosis, including hepatic encephalopathy, variceal bleeding, hepatocellular carcinoma, and mortality, were similar among groups. Lamivudine had to be changed to another drug for 32.4% of the patients. CONCLUSIONS Tenofovir and entecavir are effective and safe for long-term use in patients with compensated or decompensated cirrhosis from HBV infection.
Platelets | 2014
Serta Kilincalp; Fuat Ekiz; Omer Basar; Ayte Mr; Sahin Coban; Baris Yilmaz; Akif Altinbas; Nurcan Basar; Bora Aktas; Yaşar Tuna; Erbiş H; Engin Uçar; Elife Erarslan; Osman Yüksel
Abstract Gastric cancer is the fourth most frequent cancer and the second cause of cancer-related deaths worldwide. The early diagnosis of gastric cancer is fundamental in decreasing the mortality rates. It has been shown that MPV level is a sign of inflammation in hepatocellular carcinoma and pancreatic adenocarcinoma. The aim of this study is to examine whether MPV would be a useful inflammatory marker for differentiating gastric cancer patients from healthy controls. Thirty-one gastric cancer patients and 31 age-sexes matched healthy subjects included into the study. Patients with hypertension, hematological and renal disease, heart failure, chronic infection, hepatic disorder and other cancer were excluded from the study. MPV level was significantly higher in pre-operative gastric cancer patients compared to healthy subjects (8.31 fL vs. 7.85; p: 0.007). ROC analysis suggested 8.25 fL as the cut-off value for MPV (AUC: 0.717, sensitivity: 61%, specificity: 81%). Surgical tumor resection resulted in a significant decrease in MPV level (8.31 fL vs. 7.55 fL; p: 0.001). No significant difference was found in MPV level between the post-operative group and control subjects. We did not find statistically significant difference between MPV and TNM stages. In conclusion, changes in MPV values may be used as an easily available biomarker for monitoring the healthy patients for GC risk and may prompt physicians to make an early diagnosis of GC.
Clinics and Research in Hepatology and Gastroenterology | 2013
Omer Basar; Barış Yımaz; Fuat Ekiz; Zeynep Ginis; Akif Altinbas; Bora Aktas; Yaşar Tuna; Şahin Çoban; Namık Delibaş; Osman Yüksel
BACKGROUND AND AIM The aim of this study was to assess and compare the performance of a series of non-invasive tests to detect fibrosis in patients with chronic hepatitis B (CHB). PATIENTS AND METHODS Seventy-six patients with CHB, whose blood samples were collected and biopsies were done on the same day, were included in this study. Pre-treatment calculations of aspartate aminotransferase to platelet ratio index (APRI), Forns index, FIB-4, S-index, Shanghai Liver Fibrosis Groups index (SLFG) and Hepascore(®) were done and relations with mild and advanced fibrosis and cirrhosis were assessed. Post-treatment values of APRI, Forns index, FIB-4, S-index with oral antiviral agents were also investigated. RESULTS APRI, S-index, SLFG, FIB-4, Forns index and Hepascore(®) had 0.669, 0.669, 0.739, 0.741, 0.753, 0.780; retrospectively Area Under the Receiver Operating Characteristic Curve (AUROC) for significant fibrosis. APRI, Forns index, S-index, FIB-4, SLFG, and Hepascore(®) had 0.681, 0.714, 0.715, 0.738, 0.747, 0.777 retrospectively AUROC for advanced fibrosis. APRI, SLFG, FIB-4, Forns index, S-index, and Hepascore(®) had 0.741, 0.742, 0.768, 0.779, 0.792, 0.824 retrospectively AUROC for cirrhosis. APRI, Forns index, FIB-4 and S-index were significantly lower in post-treatment group compared with pre-treatment group (P-values: <0.05, 0.001, 0.003, 0.018; respectively). CONCLUSION Hepascore(®) showed the best performance to predict significant fibrosis. Our study also suggests that the use of non-invasive test to predict fibrosis in patients with CHB may reduce the need for liver biopsy and may help to monitor the efficacy of treatment.
Scandinavian Journal of Clinical & Laboratory Investigation | 2012
Omer Basar; Erdem Akbal; Seyfettin Köklü; Erdem Koçak; Yaşar Tuna; Fuat Ekiz; Selcan Gültuna; Fatma Meriç Yιlmaz; Temuçin Aydoğan
Abstract Background and aims. Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver pathology worldwide and is strongly associated with obesity and insulin-resistance and food intake. Nesfatin-1 is a new peptide that controls appetite and food intake. The objective of this research was to examine the serum concentrations of nesfatin-1 in NAFLD. Material and methods. Thirty NAFLD patients who had elevated liver enzymes and 40 age- and sex-matched healthy subjects were included in this study. NAFLD was diagnosed and graded with the findings of liver ultrasound scan. Nesfatin-1 concentrations were measured using an ELISA method and the relationship between nesfatin-1 and metabolic parameters were investigated. The subjects were divided into two groups according to their body mass index (≥ 30 and < 30) and nesfatin-1 concentrations were examined between both groups. Results. Serum nesfatin-1 concentrations in NAFLD patients were lower than healthy controls (0.26 ± 0.14 ng/ml, 0.38 ± 0.18 ng/ml, respectively, and p = 0.008). We found a negative correlation between nesfatin-1 and fasting glucose and body mass index. In obese subjects, serum nesfatin-1 concentrations were significantly lower when compared with non-obese subjects (0.26 ± 0.12 ng/ml, 0.37 ± 0.19 ng/ml, respectively; p = 0.014). In addition, we showed that nesfatin-1 concentrations in subjects with insulin resistance were significantly lower in comparison with insulin-sensitive ones (0.27 ± 0.17 ng/ml, 0.38 ± 0.17 ng/ml, respectively; p = 0.015). Conclusion. Our study has shown that nesfatin-1 concentrations were reduced in NAFLD. The results of this study indicate that nesfatin-1 may have a significant role in NAFLD.
Archives of Medical Research | 2013
Erdem Akbal; Seyfettin Köklü; Erdem Koçak; Başak Çakal; Fahri Güneş; Omer Basar; Yaşar Tuna; Mehmet Şenes
BACKGROUND AND AIMS Liver fatty acid-binding protein (L-FABP) is a small molecule. The aim of this study was to examine L-FABP levels and to detect its diagnostic value in chronic hepatitis C (CHC). METHODS We studied 22 patients with CHC and 20 healthy control subjects. Patients with persistently elevated serum aminotransferases and positive HCV RNA were included in the study. Patients with CHC underwent percutaneous liver biopsy. Serum level of L-FABP was determined by ELISA method. RESULTS Patients with CHC had significantly increased levels of L-FABP compared to controls. A strong correlation between serum L-FABP concentrations and aspartate aminotransferases, alanine aminotransferases, HCV RNA levels and hepatic inflammation was found. When a cut-off value was 29,000 pg/mL for L-FABP, sensitivity and specificity were 75 and 100%, respectively. Positive and negative predictive values for L-FABP were 100 and 78%, respectively. CONCLUSIONS Serum L-FABP is used as a new diagnostic marker to detect liver injury.
Blood Coagulation & Fibrinolysis | 2013
Erdem Akbal; Selim Demirci; Erdem Koçak; Seyfettin Köklü; Omer Basar; Yaşar Tuna
Vascular thrombosis and systemic hypercoagulable states are known complications of pancreatitis. Higher levels of mean platelet volume (MPV) have been associated with thrombotic diseases. However, a few studies have investigated the association between acute pancreatitis and MPV. We aimed to investigate whether there is a difference of MPV and coagulation parameters in patients with active and remission in acute pancreatitis. We included 24 consecutive patients with biliary acute pancreatitis and 24 consecutive healthy age-matched and sex-matched controls. Full blood counts and other laboratory tests were collected at onset and remission. The MPV was significantly higher in patients with acute pancreatitis at admission 8.6 ± 1.4 fl than controls 7.6 ± 0.7 fl (P = 0.005). We detected positive correlation between, aspartate aminotransferase, alanine aminotransferase, &ggr;-glutamyltransferase, amylase, lipase, and glucose, BMI, D-dimer and MPV. However, there was negative correlation between progression, thrombocyte counts, hemoglobin and MPV. As a result higher MPV levels in acute pancreatitis may reflect hypercoagulation associated with pancreatitis.
Scandinavian Journal of Gastroenterology | 2016
Zeynep Goktas; Seyfettin Köklü; Derya Dikmen; Omer Ozturk; Bulent Yilmaz; Mehmet Asil; Huseyin Korkmaz; Yaşar Tuna; Murat Kekilli; Evrim Karamanoğlu Aksoy; Hayretdin Koklu; Aslıhan Demir; Gülşah Köklü; Serab Arslan
ABSTRACT Objective: Research data demonstrating nutritional habits of functional dyspepsia (FD) patients are very limited. This is the first study to evaluate nutritional habits in FD subgroups according to Rome III criteria. Our aim was to evaluate nutritional habits of FD patients and determine the food items that may provoke a dyspepsia symptom. Methods: A total of 168 adults with FD and 135 healthy control subjects participated in the study. FD subjects were divided into epigastric pain syndrome (EP-FD), postprandial distress syndrome (PS-FD), mixed (MX-FD) subgroups according to Rome Criteria III. Subjects completed a questionnaire that included a short-form food frequency questionnaire. Furthermore, subjects were asked to list the food items that were causing a dyspepsia symptom. Results: Functional dyspepsia subjects had a slightly higher BMI (26.1 ± 4.97 kg/m2) than control subjects (24.6 ± 4.08 kg/m2). The most common symptom triggering foods among all the FD groups were fried and fatty foods (27.1%), hot spices (26.4%), and carbonated drinks (21.8%). In FD subgroups, carbonated drinks were more likely to cause a symptom in PS-FD group (37.3%) than MX-FD (25.7%) and EP-FD (22.1%) groups. There was no difference in frequency of main meals and snacks among any of the groups. Conclusion: Fatty and spicy foods and carbonated drinks were the most common symptom triggering food items in FD group. In subgroups, carbonated drinks and legumes were more likely to cause a symptom in PS-FD. Removing these food items during the course of treatment might help alleviate the symptoms.
Annals of Nutrition and Metabolism | 2013
Akif Altinbas; Bora Aktas; Baris Yilmaz; Fuat Ekiz; Murat Deveci; Omer Basar; Zahide Simsek; Sahin Coban; Yaşar Tuna; Muhemmet Fatih Uyar; Osman Yüksel
Background/Aims: An unsuccessful colonoscopy procedure is often related to inadequate bowel cleansing. It is difficult for patients to finish the whole 4 liters of polyethylene glycol-electrolyte lavage (PEG-EL) because of its salty taste and the large quantity. Pineapple juice has been shown to be an effective agent in the dissolution of undigested food in the stomach. This study assessed the effectiveness of both 2 and 4 liters of PEG-EL in precolonoscopic bowel cleansing and the quality of colonoscopic cleaning by adding 1 liter of pineapple juice to a reduced-volume PEG-based regime. Methods: The patients were chosen from those undergoing a colonoscopic procedure. A total of 126 patients were randomized into 3 groups receiving 3 different PEG-EL (Golytely®) regimes, i.e. 4 liters of PEG-EL (group 1, n = 44), 2 liters of PEG-EL (group 2, n = 39) or 2 liters of PEG-EL with 1 liter of pineapple juice (Dimes® 100%; group 3, n = 43). Results: Both the 4- and 2-liter PEG-EL regimes resulted in similar bowel cleansing scores in all parts of the colonic segments. However, adding 1 liter of pineapple juice to the reduced-volume PEG-EL regime improved the quality of the cleansing on the right side of the colon and in the transverse colon. Adequate bowel cleansing was achieved in 68.1% of the patients in group 1, 63.9% in group 2 and 80% in group 3 (the lowest score in one of the segments). On the other hand, the tolerability of the regimes was similar in all 3 groups (p = 0.509). Conclusions: Reduced PEG-EL (2 rather than 4 liters) may be sufficient for precolonoscopic bowel cleansing in the Turkish population. Administration of pineapple juice in the reduced-dose preparation regime may improve the quality of the bowel cleaning.
Annals of Transplantation | 2015
Vural Taner Yilmaz; Burak Veli Ülger; İbrahim Aliosmanoglu; Halil Erbis; Yaşar Tuna; Halide Akbas; Sebahat Ozdem; Ramazan Cetinkaya; Gultekin Suleymanlar; Huseyin Kocak
BACKGROUND The aim of this study was to evaluate the long-term outcomes of renal transplantation from Hbs Ag-positive donors to Hbs Ag-negative recipients. MATERIAL AND METHODS A total of 78 patients who underwent renal transplantation in our clinic between January 2006 and May 2014 were included in the study. Patients were divided into 2 groups: Group 1: Donor Hbs Ag (+) (n=26, Hbs Ab (-), Hbe Ag (-), Hbe Ab (+), Hbc Ig total (+) and HBV DNA (+), male/female (M/F): 16 (61.5%)/10 (38.5%), and Group 2: Donor Hbs Ag (-) (n=52, M/F: 41 (78.8%)/11 (21.2%). Hbs Ab levels were similar in recipients in both groups. Data were collected retrospectively. Analyses were performed by using SPSS 20.0 software, and patient and graft survival were measured by using Kaplan-Meier survival curve and compared by using the log-rank test. RESULTS Demographic data were similar in the 2 groups. The rate of acute Hepatitis B infection was significantly higher in Group 1 than in Group 2 [n=3 (11.5%) vs. n=0 (0%), respectively, p=0.012]. Acute hepatitis B attacks were detected in vaccinated patients. Graft survival rates (groups 1 and 2, respectively; at 1st, 3rd, 5th and 8th years: 95% vs. 96%, 95% vs. 94%, 85% vs. 88%, 85% vs. 82%, p=0.970) and patient survival rates (p=0.098), acute rejection rates (p=0.725), delayed graft function, chronic allograft dysfunction, new-onset diabetes after transplantation (NODAT), cytomegalovirus infection, and the need for postoperative dialysis and plasmapheresis were similar between groups. CONCLUSIONS Our study revealed that the risk of developing acute hepatitis B was higher in patients renally transplanted from Hbs Ag (+) donors, but the other clinical outcomes were similar between groups.
Arab Journal of Gastroenterology | 2017
Mete Akin; Erhan Alkan; Yaşar Tuna; Tolga Yalçinkaya; Bülent Yildirim
BACKGROUND AND STUDY AIMS Upper gastrointestinal (GI) bleeding is a common medical emergency. Endoscopic treatments often lead to better therapeutic outcomes than conventional conservative treatments. This study aimed to investigate and compare the use of heater probe coagulation (HPC) and argon plasma coagulation (APC) together with epinephrine injection for the treatment of Mallory-Weiss tears and high-risk ulcer bleeding. PATIENTS AND METHODS A total of 97 patients (54 in the HPC group and 43 in the APC group) who were diagnosed with upper GI bleeding secondary to a Mallory-Weiss tear or high-risk gastric or duodenal ulcers were included in the study. Lesions were classified according to the Forrest classification. The HPC and APC groups were compared in terms of initial haemostasis, re-bleeding in the early period, need for surgery, average need for transfusion, and duration of hospital stay. RESULTS There were no significant differences between the HPC and APC groups in terms of ensuring initial haemostasis (98% vs. 97.5%, p>0.05), re-bleeding rates (17% vs. 19%, p>0.05), need for surgery (2% vs. 9%, p>0.05), average need for transfusion (3.7±2.11 vs. 3.4±2.95 units, p>0.05), and average duration of hospital stay (4.6±2.24vs. 5.3±3.23days, p>0.05). CONCLUSION There was no difference between HPC and APC when used together with epinephrine injection for the treatment of Mallory-Weiss tear and high-risk ulcer bleeding.