Yazar "Colak, Yasar" seçeneğine göre listele
Listeleniyor 1 - 8 / 8
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Concentrations of connective tissue growth factor in patients with nonalcoholic fatty liver disease: Association with liver fibrosis(Hindawi Ltd, 2012) Colak, Yasar; Senates, Ebubekir; Coskunpinar, Ender; Oltulu, Yasemin Musteri; Zemheri, Ebru; Ozturk, Oguzhan; Doganay, LeventAim: In this study, we aimed to investigate the relationship between the histological fibrosis stage of nonalcoholic fatty liver disease (NAFLD) and serum connective tissue growth factor (CTGF) to determine the usefulness of this relationship in clinical practice. Methods: Serum samples were collected from 51 patients with biopsy-proven NAFLD and 28 healthy controls, and serum levels of CTGF were assayed by ELISA. Results: Levels of CTGF were significantly higher in patients with NAFLD compared with controls (P = 0.001). The serum CTGF levels were significantly increased, that correlated with histological fibrosis stage, in patients with NAFLD [in patients with no fibrosis (stage 0) 308.2 +/- 142.9, with mild fibrosis (stage 1-2) 519.9 +/- 375.2 and with advanced fibrosis (stage 3-4) 1353.2 +/- 610 ng/l, P < 0.001]. Also serum level of CTGF was found as an independent predictor of histological fibrosis stage in patients with NAFLD (beta = 0.662, t = 5.6, P < 0.001). The area under the ROC curve was estimated 0.931 to separate patients with severe fibrosis from patients with other fibrotic stages. Conclusion: Serum levels of CTGF may be a clinical utility for distinguishing NAFLD patients with and without advanced fibrosis.Öğe Evaluation of gallbladder kinetics in patients with nonalcoholic fatty liver disease(Wiley-Blackwell, 2013) Colak, Yasar; Bozbey, Gulcin; Senates, Ebubekir; Doganay, Levent; Coskunpinar, Ender; Ozturk, Oguzhan; Mesci, Banu[Abstract Not Available]Öğe Gallstone Disease Does Not Predict Liver Histology in Nonalcoholic Fatty Liver Disease(Editorial Office Gut & Liver, 2014) Yilmaz, Yusuf; Ayyildiz, Talat; Akin, Hakan; Colak, Yasar; Ozturk, Oguzhan; Senates, Ebubekir; Tuncer, IlyasBackground/Aims: We sought to examine whether the presence of gallstone disease (GD) in patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD) is associated with liver fibrosis and histological nonalcoholic steatohepatitis (NASH) score. Methods: We included 441 Turkish patients with biopsy-proven NAFLD. GD was diagnosed in the presence of sonographic evidence of gallstones, echogenic material within the gallbladder with constant shadowing and little or no visualization of the gallbladder or absence of gallbladder at ultrasonography, coupled with a history of cholecystectomy. Results: Fifty-four patients (12.2%) had GD (GD+ subjects). Compared with the GD- subjects, GD+ patients were older, had a higher body mass index and were more likely to be female and have metabolic syndrome. However, GD+ patients did not have a higher risk of advanced fibrosis or definite NASH on histology. After adjustment for potential confounding variables, the prevalence of GD in NAFLD patients was not associated with significant fibrosis (>= 2) (odds ratio [OR], 1.06; 95% confidence interval [Cl], 0.53 to 2.21; p=0.68) or definite NASH (OR, 1.03; 95% Cl, 0.495 to 2.12; p=0.84). Conclusions: The presence of GD is not independently associated with advanced fibrosis and definite NASH in adult Turkish patients with biopsy-proven NAFLD.Öğe Hepatic expression and serum levels of syndecan 1 (CD 138) in patients with nonalcoholic fatty liver disease(Informa Healthcare, 2012) Yilmaz, Yusuf; Eren, Fatih; Colak, Yasar; Senates, Ebubekir; Celikel, Cigdem Ataizi; Imeryuz, NeseBackground and aims. Syndecan-1 (CD 138) is a transmembrane heparan sulfate proteoglycan expressed in the liver which may exert metabolic effects by mediating the hepatic clearance of triglyceride-rich lipoproteins. In the present study, we assayed serum levels and the hepatic expression of syndecan-1 and examined their association with clinical, biochemical, and histologic phenotypes in patients with histology-proven nonalcoholic fatty liver disease (NAFLD). Methods. A total of 59 patients with biopsy-proven NAFLD and 54 matched controls were enrolled. The analysis of syndecan-1 expression in liver biopsies was performed by immunohistochemistry on formalin-fixed, paraffin-embedded samples. Serum syndecan-1 levels were measured by ELISA. Results. NAFLD patients had significantly higher serum syndecan-1 levels [median: 61 ng/mL (interquartile range: 36-97 ng/mL)] than controls [median: 37 ng/mL (interquartile range: 25-59 ng/mL, Mann Whitney U test, p < 0.001]. However, we did not find any significant association between serum syndecan-1 and the mean syndecan-1 immunohistochemical score (n = 59, r = 0.064, p = 0.63). Interestingly, the syndecan-1 immunohistochemical score was an independent predictor of HDL cholesterol in NAFLD patients (beta = 0.27; t = 1.99, p < 0.05). Conclusions. Our data suggest that serum syndecan-1 levels are raised in patients with NAFLD. Moreover, the syndecan-1 immunohistochemical score in the liver is independently associated with HDL cholesterol in this group of patients. These pilot results support further investigation of this molecule in metabolic liver diseases.Öğe HLA DQB1 alleles are related with nonalcoholic fatty liver disease(Springer, 2014) Doganay, Levent; Katrinli, Seyma; Colak, Yasar; Senates, Ebubekir; Zemheri, Ebru; Ozturk, Oguzhan; Enc, Feruze YilmazNonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease. NAFLD is a complex disease and inflammation is a crucial component in the disease pathogenesis. Recent genome wide association studies in hepatology area highlighted significant relations with human leukocyte antigen (HLA) DQ region and certain liver diseases. The previous animal models also emphasized the involvement of adaptive immune system in the liver damage pathways. To investigate possible polymorphisms in the HLA region that can contribute to the immune response affecting the NAFLD, we enrolled 93 consecutive biopsy proven NAFLD patients and a control group consisted of 101 healthy people and genotyped HLA DQB1 alleles at high resolution by sequence specific primers-polymerase chain reaction. The mean NAFLD activity score (NAS) was 5.2 +/- 1.2, fibrosis score was 0.9 +/- 0.9, ALT was 77 +/- 47.4 U/L, AST was 49.4 26.3 U/L. Among 13 HLA DQB1 alleles analyzed in this study, DQB1*06:04 was observed significantly at a more frequent rate among the NAFLD patients compared to that of healthy controls (12.9 vs. 2 % chi(2) = 8.6, P = 0.003, P-c = 0.039, OR: 7.3 95 % CI 1.6-33.7). In addition, the frequency of DQB1*03:02 was significantly higher in the healthy control group than the NAFLD patients (24.8 vs. 7.5 %, chi(2) = 10.4, P = 0.001, P-c = 0.013, OR: 0.2, 95 % CI 0.1-0.6). NAFLD patients were grouped according to their fibrosis score and NAS. The distribution of DQB1 alleles over stratified NAFLD patients did not reveal any statistically significant relation. Taken together, immune repertoire of individuals may have an effect on NAFLD pathogenesis and therefore, in NA-FLD, adaptive immunity pathways should be investigated.Öğe Linking nonalcoholic fatty liver disease to hepatocellular carcinoma: from bedside to bench and back(Sage Publications Ltd, 2013) Yilmaz, Yusuf; Colak, Yasar; Kurt, Ramazan; Senates, Ebubekir; Eren, FatihAims and background. Nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) are two major causes of liver disease worldwide. Epidemiological and clinical data have clearly demonstrated that NAFLD and its associated metabolic abnormalities are a risk factor for HCC. Traditionally, the mechanisms whereby NAFLD acts as a risk for HCC are believed to include replicative senescence of steatotic hepatocytes and compensatory hyperplasia of progenitor cells as a reaction to chronic hepatic injury. Recent years have witnessed significant advances in our understanding of the mechanisms underlying the link between NAFLD and HCC. Methods. In the present review, we provide an update on the pathophysiological pathways linking NAFLD and its associated metabolic derangements to malignant hepatic transformation, with a special focus on insulin resistance, adipokines, inflammation, and angiogenesis. We will also discuss the potential therapeutic implications that such molecular links carry. Results. Although treating NAFLD could reduce the risk of malignant hepatic transformation, no long-term studies focusing on this issue have been conducted thus far. Insulin resistance, inflammation as well as derangements in adipokines and angiogenic factors associated with NAFLD are closely intertwined with the risk of developing HCC. Conclusions. Traditional therapeutic approaches in NAFLD including metformin and statins may theoretically reduce the risk of HCC by acting on common pathophysiological pathways shared by NAFLD and HCC.Öğe Not only type 2 diabetes but also prediabetes is associated with portal inflammation and fibrosis in patients with non-alcoholic fatty liver disease(Elsevier Science Inc, 2014) Yilmaz, Yusuf; Senates, Ebubekir; Yesil, Atakan; Ergelen, Rabia; Colak, YasarAims: Growing evidence suggests that not only type 2 diabetes (T2D) but also prediabetes (PD) is common in patients with non-alcoholic fatty liver disease (NAFLD). However, few data exist on how PD impacts the histological characteristics of NAFLD patients. In this exploratory study, we sought to investigate the associations of PD and T2D with the severity of the histological features in patients with NAFLD. Methods: The population consisted of 280 patients with biopsy-proven NAFLD. The associations of PD and T2D with the severity of histological features of NAFLD were analyzed using multiple logistic (or ordinal logistic) regression models after adjustment for confounding factors. Results: PD and T2D was noted in 102 (36.4%) and 92 (32.8%) of patients, respectively. Of the 92 patients with T2D, ten (10.9%) were diagnosed de novo after the OGTT. PD and T2D were significantly associated with more severe portal inflammation (P < 0.01); the adjusted odds ratios (ORs) of PD and T2D for having a higher grade of portal inflammation were 1.8 [95% CI, 1.1, 3.2] and 2.6 [95% CI, 1.3, 5.8]), respectively. A similar relationship was observed for liver fibrosis (P < 0.001); specifically, the adjusted ORs of PD and T2D for having a higher grade of hepatic fibrosis were 2.4[95% CI, 1.3, 3.7] and 3.8 [95% CI, 1.9, 6.1]), respectively. Conclusion: Not only T2D but also PD is independently associated with portal inflammation and fibrosis in NAFLD patients. PD may be useful as a clinical indicator of patients who are likely to have already more severe histological findings. (C) 2014 Elsevier Inc. All rights reserved.Öğe Serum osteopontin levels as a predictor of portal inflammation in patients with nonalcoholic fatty liver disease(Elsevier Science Inc, 2013) Yilmaz, Yusuf; Ozturk, Oguzhan; Alandab, Yesim Ozen; Senates, Ebubekir; Colak, Yasar; Doganay, Hamdi Levent; Coskunpinar, EnderBackground: Osteopontin is a secreted phosphorylated glycoprotein that is expressed by a variety of cell types and that mediates numerous and diverse biological functions. Osteopontin knockout mice are protected from obesity-induced hepatic steatosis. In the present study, we sought to investigate whether serum osteopontin concentrations are associated with liver histology in patients with nonalcoholic fatty liver disease. Methods: Serum levels of osteopontin were measured by enzyme-linked immunosorbent assay in 179 Well-characterized patients with nonalcoholic fatty liver referred for liver histology and 123 control subjects. Results: Serum osteopontin levels were markedly higher in patients with nonalcoholic fatty liver disease than in controls (p < 0.001). Multivariable analysis showed that osteopontin levels were strongly and independently associated with both portal inflammation (beta = 0.294, p < 0.01) and serum aminotransferase levels (aspartate aminotransferase: beta = 0.295, p < 0.01; alanine aminotransferase; beta = 0.285, p < 0.01). Conclusion: In summary, these data demonstrate that serum levels of osteopontin are elevated in nonalcoholic fatty liver disease and are a significant independent predictor of portal inflammation in this clinical entity. (C) 2012 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
