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Dive into the research topics where Omer Basar is active.

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Featured researches published by Omer Basar.


Atherosclerosis | 2002

Metabolic syndrome: major impact on coronary risk in a population with low cholesterol levels—a prospective and cross-sectional evaluation

Altan Onat; Köksal Ceyhan; Omer Basar; Burak Erer; Sadık Toprak; Vedat Sansoy

UNLABELLED The prevalence and the excess coronary heart disease (CHD) risk of the metabolic syndrome (MS) and its components were investigated in the Turkish Adult Risk Factor Study in both a prospective and a cross-sectional manner. In a population sample, representative of Turkish adults who have low levels of high- and low-density lipoprotein-cholesterol (HDL-C and LDL-C), MS was identified in conformity with the definition used in the recent NCEP guidelines. Prospective analysis was based on 2398 men and women (mean age at baseline 49.1+/-13 years) who had a baseline examination in 1997/98 and were followed-up for a mean of 3 years. CHD was diagnosed based on clinical findings and Minnesota coding of resting electrocardiograms. Fatal and nonfatal CHD developed in 126 subjects. 27% of men and 38.6% of women were found to have MS at baseline examination. When adjusted for age, MS was an independent predictor of subsequent overall fatal and nonfatal CHD in both genders, displaying an RR of 1.71. At the final cross-sectional evaluation, coronary risk associated with MS in men was primarily accounted for by standard MS components (largely inherent in glucose intolerance, hypertension and in a surrogate of small, dense LDL particles), in addition to a minor independent contribution by C-reactive protein (CRP). In women with MS, a substantial residual coronary risk remained after controlling for five components, which was partly accounted for by levels of LDL-C and CRP. It was estimated that MS was the culprit in just over half the cases of CHD in Turkey. CONCLUSION MS was the major determinant of CHD risk in a population having generally low levels of HDL-C and LDL-C in middle-aged and elderly adults, extending to three out of every eight adults, and imposing an overall excess CHD risk of approximately 70%. In contrast to men, a substantial residual coronary risk is retained in Turkish women after controlling for five MS components.


Platelets | 2009

An overlooked indicator of disease activity in ulcerative colitis: Mean platelet volume

Osman Yüksel; Helvaci K; Omer Basar; Seyfettin Köklü; Sedat Caner; Helvaci N; Abayli E; Altiparmak E

Many non-invasive tests have been studied for diagnosis and determining the activation degree of inflammatory bowel disease (IBD). Nevertheless, an ideal test has not been found yet. Mean platelet volume (MPV) is influenced by the inflammation. In a few study, decreased platelet volume have been reported in IBD. The aim of this study is to determine whether platelet volume would be useful in ulcerative colitis (UC) activity. Additionally we have analyzed overall accuracy of MPV in disease activity and compared with other inflammatory markers. A total of 61 UC patients (male/female : 41/20), and 27 healthy subjects (male/female : 18/9) were enrolled into the study. For all subjects following tests were performed; ESR, CRP, white blood cell count and mean platelet volume. A statistically significant decrease in MPV was noted in patients with UC (8.29 ± 1.02fL) compared with healthy controls (8.65 ± 0.79 fL). MPV of active UC (8.06 ± 1.19 fL) patients were significantly lower than that of inactive UC (8.45 ± 0.87 fL). Overall accuracy of MPV in determination of active UC was 71% (with sensitivity 67%, specificity 73%). A negative correlation was found between MPV and endoscopic activity index (r : -0.358 p : 0.005). In UC, MPV did not correlate with ESR, CRP and white blood cell. Our study showed that MPV reduced in UC, particularly in patients with active UC. Decreased MPV may be an indicator for increased disease activity in patients with UC.


Inflammatory Bowel Diseases | 2009

Mucocutaneous manifestations in inflammatory bowel disease

İlhami Yüksel; Omer Basar; Hilmi Ataseven; Ibrahim Ertugrul; Mehmet Arhan; Mehmet Ibis; Ulku Dagli; Bilge Tunc Demirel; Aysel Ülker; Sema Secilmis; Saşmaz N

Background: The aim of this study was to evaluate the prevalence and features of the major cutaneous manifestations (erythema nodosum [EN] and pyoderma gangrenosum [PG]) and to determine the associations between cutaneous manifestations and other extraintestinal manifestations in patients with inflammatory bowel disease (IBD). Methods: The mucocutaneous manifestations of patients with IBD were studied between December 2002 and June 2007. All patients underwent a detailed whole body examination by a gastroenterologist and dermatologist. Results: In all, 352 patients were included in this study; 34 patients (9.3%) presented with at least 1 major cutaneous manifestation. The prevalence of EN (26 patients) and PG (8 patients) in IBD was 7.4% and 2.3%, respectively. EN was more common in Crohns disease (16/118) than ulcerative colitis (10/234) (P = 0.002). EN was found to be related to disease activity of the bowel (P = 0.026). The prevalence of arthritis was significantly higher in the IBD patients with EN (11/26) than in IBD patients without EN (53/326) (P = 0.006). Arthritis was more common in IBD patients with PG (7/8) than in IBD patients without PG (57/344) (P = 0.00). IBD patients with PG were significantly more likely to have uveitis (1/8) compared with IBD patients without PG (5/344) (P = 0.017). Conclusions: We found the prevalence of 2 important cutaneous manifestations to be 9.3% in IBD in Turkish patients. EN was found to be more common in Crohns disease and is associated with an active episode of bowel disease and peripheral arthritis. In addition, PG was connected with uveitis and peripheral arthritis. (Inflamm Bowel Dis 2009)


Clinical Gastroenterology and Hepatology | 2013

Long-term Efficacy and Safety of Lamivudine, Entecavir, and Tenofovir for Treatment of Hepatitis B Virus–Related Cirrhosis

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

Mean platelet volume could be possible biomarker in early diagnosis and monitoring of gastric cancer.

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.


European Journal of Gastroenterology & Hepatology | 2013

APRI, the FIB-4 score, and Forn's index have noninvasive diagnostic value for liver fibrosis in patients with chronic hepatitis B.

Fatma Ucar; Sevilay Sezer; Zeynep Ginis; Gulfer Ozturk; Aynur Albayrak; Omer Basar; Fuat Ekiz; Sahin Coban; Osman Yüksel; Ferah Armutcu; Erdem Akbal

Objectives The aim of this study was to evaluate the potential use of serum transforming growth factor-&bgr;1 (TGF-&bgr;1), tissue inhibitor of metalloproteinase-1 (TIMP-1), fetuin-A, and fibroblast growth factor 21 (FGF21) in the detection of liver fibrosis in patients with chronic hepatitis B (CHB). The value of the noninvasive fibrosis models – that is, the aspartate aminotransferase to platelet ratio index (APRI), the fibrosis index based on the four factors (FIB-4) score, and Forn’s index – was also examined. Materials and methods CHB patients who underwent liver biopsy for the evaluation of fibrosis were included in the study. A total of 73 patients were divided into two groups according to their METAVIR scores (F0–1, no/minimal fibrosis; F2–4, significant fibrosis). Serum levels of TGF-&bgr;1, TIMP-1, fetuin-A, and FGF21 were measured besides APRI, FIB-4, and Forn’s scores. The area under the receiver operating characteristic curve was measured for each parameter, followed by calculation of sensitivity, specificity, and positive and negative predictive values. Results APRI, FIB-4, and Forn’s index scores were significantly higher in patients with significant fibrosis (P<0.05). There was no difference between no/minimal fibrosis and significant fibrosis groups in terms of serum levels of TGF&bgr;-1, TIMP-1, fetuin-A, and FGF21 (P>0.05). The areas under the receiver operating characteristic curve for TGF-&bgr;1, TIMP-1, fetuin-A, FGF21, APRI, FIB-4, and Forn’s index were 0.445, 0.483, 0.436, 0.585, 0.662, 0.687, and 0.680, respectively. Conclusion Our results suggest that serum TGF-&bgr;1, TIMP-1, fetuin-A, and FGF21 are not useful for the assessment of the extent of liver fibrosis in CHB in this patient group. However, APRI, FIB-4, and Forn’s index have a better diagnostic value in patients with significant fibrosis than in those with no/minimal fibrosis.


Digestive Diseases and Sciences | 2005

Report of 24 left-sided portal hypertension cases: a single-center prospective cohort study.

Seyfettin Köklü; Osman Yüksel; Mehmet Arhan; Sahin Coban; Omer Basar; Ömer Faruk Yolcu; Engin Uçar; Mehmet Ibis; Ibrahim Ertugrul; Sahin B

Our aim was to analyze patients diagnosed with left-sided portal hypertension prospectively and to document the complications at follow-up. Twenty-four patients with isolated splenic vein thrombosis (diagnosed by ultrasonography or angiography or intraoperatively) and/or isolated fundal varices (diagnosed by endoscopy or endosonography) were involved in this study. Demographics, clinical presentation, diagnostic and therapeutic procedures, and morbidity and mortality were recorded in their follow-up. There were 11 and 13 left-sided portal hypertension cases associated with pancreatic diseases and nonpancreatic disorders, respectively. Chronic abdominal pain and gastrointestinal bleeding were the two most common complaints. All patients except one had isolated esophageal (2 cases) or fundal (21 cases) varices. Thirteen patients had splenomegaly on ultrasonography. On Doppler sonography, the splenic vein could be evaluated in 21 of the 24 patients (9 and 6 had complete and partial occlusion, respectively, and 6 had patent blood flow). Urgent intervention with therapeutic endoscopy and splenectomy was performed for two patients each. Medical therapy was begun for three patients according to the underlying diseases. Three patients underwent elective surgery. Two patients were lost to follow-up after the first visit and the mean follow-up of the remaining 22 patients after diagnosis of left-sided portal hypertension was 20 months. Only one patient (with pancreas cancer) had gastrointestinal bleeding at follow-up. All patients with pancreas and gastric cancer died within 2–12 months. Left-sided portal hypertension has various etiologies. It may be difficult to diagnose this entity both endoscopically and radiologically. Treatment should be directed at the underlying diseases. Recurrent hemorrhage due to left-sided portal hypertension is not usual and the prognosis depends mainly on the underlying etiology.


Clinics and Research in Hepatology and Gastroenterology | 2013

Non-invasive tests in prediction of liver fibrosis in chronic hepatitis B and comparison with post-antiviral treatment results.

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 Gastroenterology | 2008

Inlet patch: Associations with endoscopic findings in the upper gastrointestinal system

İlhami Yüksel; Oğuz Üsküdar; Seyfettin Köklü; Omer Basar; Selcan Gültuna; Selman Ünverdi; Zeynel Abidin Öztürk; Demet Sengül; Ata Türker Arıkök; Osman Yüksel; Sahin Coban

Objective. Ectopic gastric tissue in the esophagus (inlet patch) mostly presents in the upper part of the esophagus and is usually under-diagnosed because of its localization. Little is known about its pathogenesis and significance. The aim of this study was to investigate whether there is an association between ectopic gastric tissue development and endoscopic features of the upper gastrointestinal tract, especially in the esophagus. Material and methods. A total of 9437 endoscopic examinations were analyzed prospectively. Endoscopic features and histological examinations of inlet patch and stomach specimens were documented. Endoscopic findings in patients with inlet patch were compared with those in patients without inlet patch. Results. Inlet patch was present in 171 (1.8%) of all patients. Forty-three (25.1%) patients with inlet patch and 519 (5.6%) patients without inlet patch had esophagitis (p=0.000). Histologically proven Barretts esophagus was more frequent among patients with inlet patch than among patients without inlet patch (3.5% versus 0.5%, p=0.000). Prevalences of hiatal hernia in the two groups were similar. Open cardia was diagnosed more frequently in the inlet patch group than in the other group (24.5% versus 10.0%, p=0.000). Helicobacter pylori colonization was detected in only 11% of inlet patch specimens, whereas 58% of stomach specimens from the same patients contained H. pylori colonies. Conclusions. Patients with inlet patch seem to have predisposing factors for gastroesophageal reflux, and Barretts esophagus is found more frequently in those patients. H. pylori colonization is involved in ectopic gastric tissue less frequently than in gastric tissue.


Digestion | 2008

Intermittent versus Continuous Pantoprazole Infusion in Peptic Ulcer Bleeding: A Prospective Randomized Study

İlhami Yüksel; Hilmi Ataseven; Seyfettin Köklü; Ibrahim Ertugrul; Omer Basar; Bülent Ödemiş; Mehmet Ibis; Nurgül Şaşmaz; Burhan Şahin

Background and Aim: Rebleeding has remained the most important determinant of poor prognosis in peptic ulcer bleeding. Gastric acid plays an important role in the pathogenesis of rebleeding. We aimed to compare the efficiency of intermittent and continuous pantoprazole infusion treatment on peptic ulcer rebleeding after endoscopic therapy. Materials and Method: In this prospective study, patients with active peptic ulcer bleeding or non-bleeding visible vessel were treated initially with endoscopic therapy. They were randomized to receive intermittent or continuous intravenous pantoprazole treatment. Rebleeding rate, duration of hospital stay, need for total blood transfusion and need for urgent surgery were compared among both groups. Results: Rebleeding rate (6.1 vs. 8.3%), duration of hospital stay (4.17 vs. 4.41), need for total blood transfusion (2.18 vs. 2.59) and need for urgent surgery (4.1 vs. 4.2%) were similar in intermittent and continuous pantoprazole infusion therapy groups, respectively. There was no bleeding-related death in either group. Conclusion: In patients with peptic ulcer bleeding, intermittent and continuous pantoprazole infusion after successful endoscopic therapy have comparable outcomes in reducing rebleeding. Both have similar effects on hospital stay, need for blood transfusion and urgent surgery. Intermittent administration has application and cost advantages over continuous infusion.

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İlhami Yüksel

Yıldırım Beyazıt University

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