Hakan Yüceyar
Celal Bayar University
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Featured researches published by Hakan Yüceyar.
Brazilian Journal of Medical and Biological Research | 2001
Murat Saruc; G. Goksel; S. Ozkaya; F. Guclu; B. Ozbakkaloglu; Hakan Yüceyar
If cytotoxin-associated gene A (CagA) status affects the response rates of therapy, then it may be possible to predict Helicobacter pylori eradication rates. We aimed to evaluate the response to eradication treatment of H. pylori infection in CagA-positive and CagA-negative patients. A total of 184 patients (93 males, 91 females, mean age 42.6 +/- 12.8 years) with H. pylori-positive chronic gastritis were studied. Subjects underwent a gastroscopy and biopsy specimens were taken from the gastric antrum, body, and fundus. Before the eradication therapy was given all patients were tested for CagA, TNF-alpha and gastrin levels. They were then prescribed lansoprazole (30 mg bid), clarithromycin (500 mg bid), and amoxicillin (1.0 mg bid) for one week. On the 8th week a second endoscopy was performed and further biopsy specimens were obtained from the same sites as in the initial endoscopy. One hundred and twenty-seven patients (69.1%) were found to be CagA positive and 57 patients (30.9%) were CagA negative. The total eradication rate was 82.6%. In the CagA-positive group this rate was 87.4%, and in the CagA-negative group it was 71.9% (P = 0.019). TNF-alpha levels were higher in the CagA-positive than in the CagA-negative group (P = 0.001). However, gastrin levels were not different between groups (P = 0.421). Our findings revealed that CagA-negative status might be a risk factor for failure of H. pylori triple therapies. The CagA pathogenicity island gives a growth advantage to H. pylori strains and has been associated with an increase in the inflammatory response at the gastric mucosal level. These properties could make CagA-positive H. pylori strains more susceptible to antibiotics.
Brazilian Journal of Medical and Biological Research | 2003
Murat Saruc; Hakan Yüceyar; Nurten Turkel; Omer Ozutemiz; Isil Tuzcuoglu; Gül Yüce; A. Huseyinov
The literature indicates that acute pancreatitis is a complication of massive hemolysis with a prevalence of about 20%. We describe an experimental model of hemolysis-induced acute pancreatitis. Hemolytic anemia was induced in rats by a single ip injection of 60 mg/kg of 20 mg/ml acetylphenylhydrazine (APH) in 20% (v/v) ethanol on the first experimental day (day 0). One hundred and fifty Wistar albino rats weighing 180-200 g were divided into three groups of 50 animals each: groups 1, 2 and 3 were injected ip with APH, 20% ethanol, and physiological saline, respectively. Ten rats from each group were sacrificed on study days 1, 2, 3, 4 and 5. Serum amylase, lipase levels and pancreatic tissue tumor necrosis factor-alpha (TNF-alpha) and platelet-activating factor (PAF) contents were determined and a histological examination of the pancreas was performed. No hemolysis or pancreatitis was observed in any of the rats in groups 2 and 3. In group 1, massive hemolysis was observed in 35 (70%) of 50 rats, moderate hemolysis in seven (14%), and no hemolysis in eight (16%). Thirty-three of 35 (94.2%) rats with massive hemolysis had hyperamylasemia, and 29 of these rats (82.8%) had histologically proven pancreatitis. The most severe pancreatitis occurred on day 3, as demonstrated by histology. Tissue TNF-alpha and PAF levels were statistically higher in group 1 than in groups 2 and 3. Acute massive hemolysis induced acute pancreatitis, as indicated by histology, in almost 80% of cases. Hemolysis may induce acute pancreatitis by triggering the release of proinflammatory and immunoregulatory cytokines.
Brazilian Journal of Medical and Biological Research | 2003
Murat Saruc; Ozden N; Nurten Turkel; Ayhan S; Demir Ma; Isil Tuzcuoglu; Akarca Us; Hakan Yüceyar
The etiology of functional dyspepsia is not known. The objective of the present study was to determine the characteristics of functional dyspepsia in Western Turkey. We divided 900 patients with functional dyspepsia into three subgroups according to symptoms: ulcer-like (UL), 321 (35.6%), motility disorder-like (ML), 281 (31.2%), and the combination (C) of these symptoms, 298 (33.1%). All patients were submitted to endoscopic evaluation, with two biopsies taken from the cardia and corpus, and four from the antrum of the stomach. All biopsy samples were studied for Helicobacter pylori (Hp) density, chronic inflammation, activity, intestinal metaplasia, atrophy, and the presence of lymphoid aggregates by histological examination. One antral biopsy was used for the rapid urease test. Tissue cagA status was determined by PCR from an antral biopsy specimen by a random sampling method. We also determined the serum levels of tumor necrosis factor-alpha (TNF-alpha) and gastrin by the same method. Data were analyzed statistically by the Kolmogorov-Smirnov test and by analysis of variance. Hp and cagA positivity was significantly higher in the UL subgroup than in the others. The patients in the ML subgroup had the lowest Hp and cagA positivity and Hp density. The ML subgroup also showed the lowest level of Hp-induced inflammation among all subgroups. The serum levels of TNF-alpha and gastrin did not reveal any difference between groups. Our findings show a poor association of Hp with the ML subgroup of functional dyspepsia, but a stronger association with the UL and C subgroups.
Annals of Saudi Medicine | 2006
Sarioğlu N; Nurten Turkel; Sakar A; Celik P; Murat Saruc; Demir Ma; Göktan C; Kirmaz C; Hakan Yüceyar; Yorgancioğlu A
To the Editor: The rate of extraintestinal involvement in inflammatory bowel diseases (IBD) was reported as 21% to 41%.1 Pulmonary involvement patterns include tracheobronchitis, tracheal stenosis, bronchitis, bronchiectasis, interstitial lung disease, necrobiotic nodule, serositis, and pulmonary vasculitis.2,3,4,5,6,7 Our aim was to evaluate lung involvement in IBD. Seventeen IBD patients were included in the study with the approval of a local ethics committee. IBD activity was evaluated by clinical, endoscopic, and histopathological findings. Patients with a previous history of lung disease were excluded. Pulmonary function tests (PFT) were carried out using a Jaeger Master Screen Pneumo device. Patients with normal PFT values were examined for bronchial hyperreactivity with methacholine. High-resolution computed tomography (HRCT) was obtained using a Siemens Emotion 2003 Spiral CT (Munich, Germancy) device. Fiberoptic bronchoscopy was applied to 15 of 17 patients who accepted the procedure. Bronchoalveolar lavage (BAL) was performed by standard technique. Mucosal biopsies were also taken from the middle lobe through the lower lobe carina on the right, and the upper lobe through the lingua carina on the left. SPSS software was used for the analysis of the data. Fisher’s exact test was used for comparison of disease activity to other parameters. Of the 17 patients, 15 had ulcerative colitis and 2 had Crohn’s disease. The mean age of 10 female (58.8%) and 7 male (41.2%) cases was 41.0±12.5 years and the mean duration of disease was 5.6±5.9 years. Six of the cases were regarded as active IBD. Respiratory symptoms were observed in 4 (23%) cases. PFT parameters were normal in all patients except one, who had restriction. Bronchial hyperreactivity was positive in 5 cases irrespective of respiratory symptoms. HRCT revealed pathology (air-trapping, emphysema, peribronchial thickening, bronchectasis, fibrosis, frosted glass, bullae) in 15 cases (88.2%). In BAL, the cell count of 7 cases (46,6%) indicated alveolitis (lymphocytic 40% and neutrophilic 6.6%) was present whereas in the mucosal biopsy of 2 cases (11.8%), submucosal inflammatory cell infiltration was observed. No relationship was found between disease activity and thorax HRCT findings, PFT, and BAL values (P=0.5). Despite the amount of research carried out on extraintestinal findings in IBD, the pathogenesis still needs clarification. In such diseases, since there is an impairment in the mucosal immune regulation of gastrointestinal system antigens, digestive enzymes, and bacteria in the luminal content; activation of immune regulatory cells by the systemic circulation occurs.8 Respiratory system pathologies can be classified as airway disease (upper airway obstruction, acute bronchitis, chronic bronchitis, chronic bronchial suppuration, bronchiectasis, bronchiolitis), parenchymal disease (cryptogenic organising pneumonia, pulmonary infiltrates and peripheral crease during the conversion period. We also observed that there were no changes in leukocyte and lymphocyte counts. We found no studies that evaluated serum ADA activity during sputum conversion in the literature so there is no data to compare with our results. Also, serum ADA activity in drug-resistant cases is not known. In these cases, serum ADA levels are expected to be high as the sputum positivity continues. The relationship between ADA and lymphocytes may be clarified by new studies in drug-resistant cases. Finally, the serum ADA level is a highly specific parameter in pulmonary tuberculosis patients. Despite acute phase reactants during sputum smear conversion, serum ADA levels do not decrease. For this reason serum ADA may be a good parameter in the follow-up of a chronic disease like tuberculosis.
Gastroenterology Nursing | 2003
Murat Saruc; Aysen Sertdemir; Nurten Turkel; Isil Tuzcuoglu; Nuri Ozden; Hakan Yüceyar
Upper gastrointestinal endoscopy can be performed without intravenous sedation but the evidence suggests most patients and endoscopists prefer some form of premedication. Intravenous diazepam or midazolam are used by the majority of endoscopists in the United States, though it is not common practice in Turkey where this study was conducted. This study aimed to evaluate the efficacy and safety of midazolam in performing upper gastrointestinal endoscopy. A total of 352 patients undergoing upper gastrointestinal endoscopy were sedated with midazolam given as a bolus injection over 5 seconds. Ages of the patients ranged between 16 and 79 years (average: 41.6 ± 12.7 years). The course of endoscopy, anterograde memory, degree of cooperation, degree of sedation, side effects, and acceptability of further intervention were evaluated by a questionnaire given to the patients and endoscopists.
Tumor Biology | 2016
Elmas Kasap; Emre Gerçeker; Seda Örenay Boyacıoglu; Hakan Yüceyar; Hatice Yıldırm; Semin Ayhan; Mehmet Korkmaz
Colorectal adenomatous polyp (CRAP) is a major risk factor for the development of sporadic colorectal cancer (CRC). Histone modifications are one of the epigenetic mechanisms that may have key roles in the carcinogenesis of CRC. The objective of the present study is to investigate the alternations in the defined histone modification gene expression profiles in patients with CRAP and CRC. Histone modification enzyme key gene expressions of the CRC, CRAP, and control groups were evaluated and compared using the reverse transcription PCR (RT-PCR) array method. Gene expression analysis was performed in the CRAP group after dividing the patients into subgroups according to the polyp diameter, pathological results, and morphological parameters which are risk factors for developing CRC in patients with CRAP. PAK1, NEK6, AURKA, AURKB, HDAC1, and HDAC7 were significantly more overexpressed in CRC subjects compared to the controls (p < 0.05). PAK1, NEK6, AURKA, AURKB, and HDAC1 were significantly more overexpressed in the CRAP group compared to the controls (p < 0.005). There were no significant differences between the CRAP and CRC groups with regards to PAK1, NEK6, AURKA, or AURKB gene overexpression. PAK1, NEK6, AURKA, and AURKB were significantly in correlation with the polyp diameter as they were more overexpressed in polyps with larger diameters. In conclusion, overexpressions of NEK6, AURKA, AURKB, and PAK1 genes can be used as predictive markers to decide the colonoscopic surveillance intervals after the polypectomy procedure especially in polyps with larger diameters.
Oncology Reports | 2015
Emre Gerçeker; Seda Örenay Boyacıoglu; Elmas Kasap; Ahmed Ramiz Baykan; Hakan Yüceyar; Hatice Yildirim; Semin Ayhan; Ender Ellidokuz; Mehmet Korkmaz
Ulcerative colitis (UC) is an important risk factor for colorectal cancer (CRC). Histone modifications are one of the epigenetic mechanisms that may have key roles in the carcinogenesis of CRC. At present, there are no studies comparing histone modification patterns of UC and CRC in the literature. Therefore the aim of the present study was to investigate whether genes, particularly those involved in histone modification, have value in patient monitoring with regards to CRC development in UC. Key gene expressions of the histone modification enzyme were assessed and compared in CRC, UC and control groups using the RT-PCR array technique. Patients were divided into subgroups based on the extent and duration of the disease and inflammatory burden, which are considered risk factors for CRC development in UC patients. In UC and CRC groups, a significantly higher overexpression of the NEK6 and AURKA genes compared to the control group was identified. In addition, there was a significantly higher overexpression of HDAC1 and PAK1 genes in the UC group, and of HDAC1, HDAC7, PAK1 and AURKB genes in the CRC group. NEK6, AURKA, HDAC1 and PAK1 were significantly overexpressed in patients with a longer UC duration. Overexpression of AURKA and NEK6 genes was significantly more pronounced in UC patients with more extensive colon involvement. HDAC1, HDAC7, PAK1, NEK6, AURKA and AURKB are important diagnostic and prognostic markers involved in the carcinogenesis of CRC. HDAC1, PAK1, NEK6 and AURKA may be considered as diagnostic markers to be used in CRC screening for UC patients.
The Turkish journal of gastroenterology | 2014
Abdülkadir Dökmeci; Yucel Ustundag; Saadettin Hulagu; Ilyas Tuncer; Meral Akdogan; Hüseyin Demirsoy; Seyfettin Köklü; Fatih Güzelbulut; Ibrahim Dogan; Ali Demir; Mesut Akarsu; Hakan Yüceyar; Osman Ozdogan; Fatih Ozdener; Seda Erdogan
BACKGROUND/AIMS To evaluate the association between insulin resistance and hepatic fibrosis in patients with chronic hepatitis C. MATERIALS AND METHODS A total of 104 chronic hepatitis C patients were included in this non-interventional, open-label, observational, multicenter, cross-sectional study conducted at 20 gastroenterology clinics in Turkey. The primary end point was the correlation between stage of hepatic fibrosis and insulin resistance evaluated via the homeostasis model of assessment-insulin resistance index. Confounders of hepatic fibrosis and insulin resistance were the secondary end points. RESULTS The mean age of patients was 52.8 years; 65.4% were female. Type 2 diabetes was present in 6.8% and insulin resistance noted in 38.0% of patients. Further, 45.7% of the patients had mild (A0/A1) and the remaining had moderate/severe (A2/A3) hepatic necroinflammatory activity. Patient distribution according to Metavir fibrosis stage was as follows: F0/F1 (57.0%); F2 (6.5%); F3 (23.7%); and F4 (12.9%). A univariate analysis revealed significant positive correlations between Metavir fibrosis stage and insulin resistance (r=0.297; p=0.007). Logistic regression analysis showed that significant predictors of insulin resistance were high alanine transaminase levels (odds ratio, 0.97; 95% confidence interval, 0.944-0.997) and liver fibrosis stage (odds ratio, 0.114; 95% confidence interval, 0.021-0.607). CONCLUSION Our findings revealed significant associations between insulin resistance and hepatic fibrosis.
Molecular Biology Reports | 2018
Seda Orenay-Boyacioglu; Elmas Kasap; Emre Gerçeker; Hakan Yüceyar; Ufuk Demirci; Fahri Bilgic; Mehmet Korkmaz
Gastric cancer (GC) development can be attributed to several risk factors including atrophic gastritis (AG), intestinal metaplasia (IM), and the presence of Helicobacter pylori (HP). Also, histone modification is an epigenetic mechanism that plays a pivotal role in GC carcinogenesis. In this preliminary study, we aimed to describe the expression profiles of histone modification in the AG, IM, and GC patient groups. A total of 80 patients with AG (n = 27), IM (n = 25), and GC (n = 28) with an additional 20 control subjects were included in the study. Expression profiles of three histone phosphorylation genes (PAK1, NEK6, and AURKA) and five histone deacetylation genes (HDACs 1, 2, 3, 5, and 7) were examined based on the results of Real Time qPCR method. It was observed that AURKA and HDAC2 genes were significantly overexpressed in all groups compared to the control (P < 0.05). In GC patients, overexpression of HDAC2 gene was detected in the absence of metastasis, and overexpression of AURKA, HDAC2, and NEK6 genes was detected in the presence of metastasis. When cancer involvements were compared, significant overexpression of the HDAC2 gene was noted in overall and corpus involvements (P < 0.05). In addition, overexpression of AURKA, NEK6, HDAC1, and HDAC2 genes and underexpression of HDAC5 gene were detected in the antrum involvement (P < 0.05). In conclusion, decreased expression of HDAC5 in GC is reported for the first time in this study, while supporting the existing literature in AURKA, NEK6, HDAC1, and HDAC2 up regulations during GC development.
Transfusion and Apheresis Science | 2017
Emre Gerçeker; Hakan Yüceyar; Elmas Kasap; Ufuk Demirci; Burcu Ceren Ekti; Ismet Aydogdu; Mine Miskioglu
Studies about leukocytapheresis have emerged with the need of search for alternatives to conventional treatment in inflammatory bowel diseases (IBD). Leukocytapheresis is a novel non-pharmacologic approach for active ulcerative colitis (UC) and Crohns disease (CD), in which leukocytes are mechanically removed from the circulatory system. Patients with active IBD treated with leukocytapheresis using a Cellsorba E column between 2012 and 2015, were enrolled in Turkey. In our experience, the results of leukocytapheresis therapy in 6 patients with CD and 20 patients with active UC were overviewed. Leukocytapheresis (10 sessions for remission induction therapy, 6 sessions for maintenance therapy) was applied to the patients with their concomitant medications. Intensive leukocytapheresis (≥4 leukocytapheresis sessions within the first 2 weeks) was used in 30% patients with active severe UC. The overall clinical remission rate in patients with UC was 80%, and the mucosal healing rate was 65%. Patients were followed for an average of 24 months. It was observed that clinical remission has continued in 65% of patients with UC. Mild relapse was observed in 3 patients with UC during follow up period. In 5 patients with CD significant clinical remission was achieved except only one patient. Surgical needs were disappeared in 3 patients with obstructive type Crohns disease. Adverse events were seen in only 4.3% of 416 sessions. Any concomitant medications did not increase the incidence of adverse events. Our results indicate that leukocytapheresis is efficacious in improving remission rates with excellent tolerability and safety in patients with IBD.