Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Muammer Kara is active.

Publication


Featured researches published by Muammer Kara.


Clinical Endocrinology | 2013

Plasma fetuin-A is associated with endothelial dysfunction and subclinical atherosclerosis in subjects with nonalcoholic fatty liver disease

Teoman Dogru; Halil Genc; Serkan Tapan; Fatih Aslan; Cemal Nuri Ercin; Fatih Ors; Muammer Kara; Erdim Sertoglu; Yildirim Karslioglu; Sait Bagci; Ismail Kurt; Alper Sonmez

Nonalcoholic fatty liver disease (NAFLD), a hepatic manifestation of metabolic syndrome (MetS) is closely associated with an increased risk of cardiovascular disease. Fetuin‐A is associated with MetS and NAFLD. We investigated the relationship of circulating fetuin‐A level with markers of endothelial dysfunction and presence of carotid atherosclerosis in subjects with NAFLD.


Upsala Journal of Medical Sciences | 2010

Mean platelet volume and its relationship with carotid atherosclerosis in subjects with non-alcoholic fatty liver disease.

Guldem Kilciler; Halil Genc; Serkan Tapan; Fatih Ors; Muammer Kara; Nuri Karadurmus; C Nuri Ercin; Yildirim Karslioglu; Selim Kilic; Sait Bagci; M. Kemal Erbil; Teoman Dogru

Abstract Background. Non-alcoholic fatty liver disease (NAFLD) is linked to an increased risk of cardiovascular disease. Mean platelet volume (MPV), a determinant of platelet activation, is an emerging risk factor for atherothrombosis. Aims. The aim of this study was to investigate the levels of MPV in subjects with NAFLD having no confounding factors for atherosclerosis such as obesity, diabetes mellitus, and hypertension. In addition, the possible relationship between MPV and carotid artery intima media thickness (CIMT), a well known marker of subclinical atherosclerosis, was also studied. Methods. MPV and CIMT levels were measured in 60 biopsy-proven NAFLD subjects and 54 healthy controls. Age and sex were similar between two groups. Results. Body mass index and waist circumference levels were higher in the NAFLD group when compared to the controls. There were no differences between the two groups regarding LDL cholesterol levels, whereas HDL cholesterol levels were lower in the NAFLD group. MPV and CIMT levels were not different between the two groups. According to the correlation analyses, CIMT levels were positively correlated to age in patients with NAFLD. However, no significant correlation was found between MPV and CIMT levels. Conclusions. The results of this study do not show any difference in MPV levels between subjects with NAFLD and controls. These finding suggests that in the absence of other metabolic risk factors, MPV might not be involved in the mechanism(s) of increased cardiovascular risk in NAFLD.


Clinical Biochemistry | 2014

The relationship of serum uric acid with non-alcoholic fatty liver disease.

Erdim Sertoglu; Cemal Nuri Ercin; Gurkan Celebi; Hasan Gurel; Huseyin Kayadibi; Halil Genc; Muammer Kara; Teoman Dogru

OBJECTIVES Non-alcoholic fatty liver disease (NAFLD) is a clinicopathological entity which is characterized by the presence of fat droplets in hepatocytes without alcohol consumption, representing a spectrum of hepatic injuries, ranging from simple steatosis (SS) to non-alcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. In recent years, experimental and observational studies suggest a role for serum uric acid (SUA) in NAFLD. However, there are few reports investigating SUA in histologically proven NAFLD. The aim of the present study was to evaluate the relationship of SUA with liver histology in non-diabetic patients with NAFLD. DESIGN AND METHODS A total of 242 male patients with NAFLD (102 with NASH and 140 with SS) were included. Histopathological evaluation was carried out according to Kleiners scoring scale. Hyperuricemia was diagnosed as SUA of more than 7 mg/dL. RESULTS The prevalence of hyperuricemia was 33.4%. SUA levels in patients with NASH were significantly higher than those of SS (p=0.035). Univariate and multivariate analyses both demonstrated that hyperuricemia had a significant association with younger age [OR (95%CI), 0.930 (0.884-0.979), p=0.005], higher body mass index [OR (95%CI), 1.173 (1.059-1.301), p=0.002] and hepatocellular ballooning [OR (95%CI), 1.678 (1.041-2.702), p=0.033]. CONCLUSIONS Hyperuricemia is a common finding in patients with NAFLD and is independently associated with early histological findings in this clinically relevant condition. Further longitudinal studies are needed to characterize the role of SUA in the natural history of NAFLD.


Diabetes Research and Clinical Practice | 2012

Elevated asymmetric dimethylarginine in plasma: An early marker for endothelial dysfunction in non-alcoholic fatty liver disease?

Teoman Dogru; Halil Genc; Serkan Tapan; Cemal Nuri Ercin; Fatih Ors; Fatih Aslan; Muammer Kara; Erdim Sertoglu; Sait Bagci; Ismail Kurt; Alper Sonmez

AIMS Non-alcoholic fatty liver disease (NAFLD) is associated with cardiovascular disease. Asymmetric dimethylarginine (ADMA) is a novel marker of endothelial dysfunction and atherosclerosis. We aimed to investigate circulating ADMA concentrations in biopsy proven NAFLD and also to search its association with carotid atherosclerosis. METHODS Sixty-seven nondiabetic and normotensive patients with NAFLD and 35 healthy controls were enrolled. Plasma ADMA was measured along with glucose, lipids and insulin levels. Insulin resistance (IR) was assessed by homeostasis model assessment-estimated insulin resistance (HOMA-IR) method. Carotid atherosclerosis was evaluated by carotid artery intima-media thickness (CIMT) using carotid ultrasonography. RESULTS ADMA levels and CIMT measurements were significantly higher in NAFLD group than the controls. However, the difference regarding the CIMT disappeared when the findings were adjusted according to the metabolic parameters and insulin sensitivity. In contrast, the difference for ADMA remained significant between two groups. No significant association was found between ADMA, CIMT and histopathological findings. CONCLUSIONS Plasma ADMA levels are increased in subjects with NAFLD. This increase seems to be independent from traditional cardiovascular risk factors, insulin resistance and liver histology. Circulating ADMA may be an earlier marker of vascular damage with respect to CIMT in subjects with NAFLD.


Scandinavian Journal of Gastroenterology | 2011

Circulating vaspin and its relationship with insulin sensitivity, adiponectin, and liver histology in subjects with non-alcoholic steatohepatitis.

Halil Genc; Teoman Dogru; Serkan Tapan; Muammer Kara; Cemal Nuri Ercin; Fatih Aslan; Murat Kantarcioglu; Yildirim Karslioglu; Erdim Sertoglu; Mehmet Kemal Erbil; Sait Bagci

Abstract Objective. Non-alcoholic steatohepatitis (NASH) is closely associated with components of metabolic syndrome. Vaspin is a novel adipocytokine that may link obesity, insulin resistance (IR), and type 2 diabetes mellitus. We aimed to investigate circulating vaspin levels in subjects with NASH and also to search for the association of vaspin with IR, adiponectin, and histological findings. Material and methods. A total of 50 male patients with NASH and 30 healthy male controls were enrolled. Vaspin and adiponectin were measured with ELISA method. Insulin sensitivity determined by homeostasis model assessment (HOMA-IR) index. Results. Plasma vaspin levels were higher and adiponectin levels were lower in NASH group compared with controls (p < 0.01 and p < 0.001, respectively). However, in multivariate analysis adjusted for glucose and lipid parameters, and HOMA-IR indexes, the difference in vaspin concentrations was disappeared. Nonetheless, the difference regarding the adiponectin levels remained significant between groups (p = 0.03). Vaspin was negatively correlated with low-density lipoprotein cholesterol (r = -0.32, p = 0.03) in subjects with NASH. Conclusions. This study indicates that circulating vaspin levels are not altered in male subjects with NASH. These results suggest that in the absence of metabolic risk factors, vaspin per se may not be involved in the pathogenesis of NASH.


Helicobacter | 2012

Low Efficacy of Clarithromycin Including Sequential Regimens for Helicobacter Pylori Infection

Abdurrahman Kadayifci; Ahmet Uygun; Guldem Kilciler; Murat Kantarcioglu; Muammer Kara; Ayhan Ozcan; Ozdes Emer

Background:  Sequential treatment for Helicobacter pylori (H. pylori) appears to achieve a better eradication rate than triple therapy. However, most of the data have been reported from the Italy, and studies from different population are needed before it is recommended in clinical practice. The present study aimed to assess and compare the efficacy of two separate clarithromycin including sequential regimens in Turkey which is well known with high clarithromycin and metronidazole resistance to H. pylori.


Metabolic Syndrome and Related Disorders | 2015

Insulin Resistance but Not Visceral Adiposity Index Is Associated with Liver Fibrosis in Nondiabetic Subjects with Nonalcoholic Fatty Liver Disease

Cemal Nuri Ercin; Teoman Dogru; Halil Genc; Gurkan Celebi; Fatih Aslan; Hasan Gurel; Muammer Kara; Erdim Sertoglu; Serkan Tapan; Sait Bagci; Manfredi Rizzo; Alper Sonmez

BACKGROUND Nonalcoholic fatty liver disease (NAFLD) is associated with obesity, type 2 diabetes mellitus, and dyslipidemia. It is well known that the presence of visceral fat increases the risk for metabolic complications of obesity, especially NAFLD. The visceral adiposity index (VAI), a novel marker of visceral fat dysfunction, shows a strong association with insulin resistance and also cardiovascular and cerebrovascular events. However, there is conflicting data regarding the association between VAI and NAFLD. Our aim was to assess the relationship between VAI, insulin resistance, adipocytokines, and liver histology, in nondiabetic subjects with NAFLD. METHODS A total of 215 male patients with biopsy-proven NAFLD were included. Among this group, serum levels of adiponectin, tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hsCRP) were measured in 101 patients whose blood samples were available. RESULTS High gamma-glutamyl transferase (GGT), high total cholesterol (TC), high triglycerides (TGs), low high-density lipoprotein cholesterol (HDL-C), and presence of metabolic syndrome were significantly associated with higher VAI, although only higher GGT and TC were independent factors on multiple linear regression analysis. On the other hand, no significant association was found between VAI and adiponectin, TNF-α, IL-6, and hsCRP levels. The multivariate analysis of variables in patients with (n=124) and without (n=91) fibrosis showed that only higher homeostasis model assessment of insulin resistance value was independently associated with liver fibrosis. CONCLUSIONS Our findings suggest that VAI is not related to the severity of hepatic inflammation or fibrosis in nondiabetic patients with NAFLD. The lack of association between the adipocytokines and VAI also implies that the VAI may not be a significant indictor of the adipocyte functions.


European Journal of Gastroenterology & Hepatology | 2015

Neutrophil-to-lymphocyte ratio is not a predictor of liver histology in patients with nonalcoholic fatty liver disease.

Muammer Kara; Teoman Dogru; Halil Genc; Erdim Sertoglu; Gurkan Celebi; Hasan Gurel; Huseyin Kayadibi; Ali F. Cicek; Cemal Nuri Ercin; Alper Sonmez

Objectives It has been reported that the neutrophil-to-lymphocyte ratio (NLR) can be measured relatively easily and can serve as a valuable index for much clinical pathology. The aim of this study was to investigate the association between NLR and hepatic histological findings in patients with nonalcoholic fatty liver disease (NAFLD). Design and methods A total of 226 consecutive patients with biopsy-proven NAFLD [nonalcoholic steatohepatitis (NASH, n=105), borderline-NASH (n=74), and simple steatosis (n=47)] were enrolled. NASH and fibrosis were diagnosed histologically using the NAFLD Clinical Research Network criteria. Results Significant differences were found in aspartate aminotransferase (P<0.001), alanine aminotransferase (P<0.001) levels, and white blood cell (P=0.007) and neutrophil counts (P=0.042) between the three groups of patients. In addition, significantly higher BMI (P=0.024), waist circumference (P=0.011), aspartate aminotransferase (P=0.003), alanine aminotransferase (P=0.005), insulin (P=0.008), and homeostasis model assessment-insulin resistance (P=0.009) levels were found in patients with fibrosis (n=133) in comparison with those without fibrosis (n=93). There was no correlation between NLR and glucose, homeostasis model assessment-insulin resistance, lipid parameters, and the NAFLD activity score. Analysis of the NLR in relation to histological findings also showed no association between these parameters. Conclusion To the best of our knowledge, this is the largest study that has investigated these relationships in this clinically relevant condition. The findings of the present study show that NLR is not associated with the severity of hepatic inflammation or fibrosis and thus cannot be recommended as a surrogate marker of liver injury in patients with NAFLD.


Scandinavian Journal of Clinical & Laboratory Investigation | 2010

Circulating levels of interleukin-18 in patients with non-alcoholic fatty liver disease

Serkan Tapan; Teoman Dogru; Muammer Kara; C Nuri Ercin; Guldem Kilciler; Halil Genc; Erdim Sertoglu; Cengizhan Acikel; Selim Kilic; Yildirim Karslioglu; Ismail Kurt; Mehmet Kemal Erbil

Abstract Background and aims. Non-alcoholic fatty liver disease (NAFLD) is strongly associated with obesity and diabetes mellitus. IL-18 is associated with obesity and metabolic syndrome. Our aim was to investigate the relationship of IL-18 with adiponectin and liver histology in subjects with NAFLD who had no additional disorder such as morbid obesity, diabetes mellitus and hypertension. Methods. Plasma levels of IL-18 and adiponectin were measured by ELISA in 96 male subjects with NAFLD [n = 65 for non-alcoholic steatohepatitis (NASH) and n = 31 for simple steatosis (SS)]. Results. IL-18 levels were not different between the two groups (p = 0.89). There was no significant association of IL-18 with adiponectin, insulin resistance and histopathological findings. Adiponectin was lower in the NASH group compared to the SS group (p = 0.02) and it was found to be negatively correlated with hepatic steatosis and fibrosis (r = −0.442, p < 0.001 and r = −0.292, p = 0.02, respectively). Conclusions. This study indicates that circulating IL-18 levels are not altered in male subjects with NAFLD. These results suggest that in the absence of metabolic risk factors, IL-18 per se may not be involved in the pathogenesis of NASH and SS.


Saudi Journal of Gastroenterology | 2015

The Relationship of Circulating Fetuin‑A With Liver Histology and Biomarkers of Systemic Inflammation in Nondiabetic Subjects With Nonalcoholic Fatty Liver Disease

Gurkan Celebi; Halil Genc; Hasan Gurel; Erdim Sertoglu; Muammer Kara; Serkan Tapan; Cengizhan Acikel; Yildirim Karslioglu; Cemal Nuri Ercin; Teoman Dogru

Background/Aims: Fetuin-A, a glycoprotein with anti-inflammatory properties, plays an important role in counter-regulating inflammatory responses. It has also been associated with insulin resistance and metabolic syndrome. We aimed to investigate circulating concentrations of fetuin-A and its possible association with hepatic and systemic inflammation in nondiabetic subjects with nonalcoholic fatty liver disease (NAFLD). Patients and Methods: We included 105 nondiabetic male subjects with NAFLD [nonalcoholic steatohepatitis (NASH, n = 86) and simple steatosis (SS, n = 19)]. Plasma levels of fetuin-A and markers of inflammation [high-sensitive C reactive protein (hsCRP), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and adiponectin] were measured by enzyme-linked immunosorbent assay method. Insulin sensitivity was determined by homeostasis model assessment of insulin resistance (HOMA-IR) index. Results: Fetuin-A was negatively correlated with age (r = −0.27, P = 0.006), however there was no association between fetuin-A and body mass index, waist circumference (WC), glucose, insulin, HOMA-IR, lipid parameters, and inflammatory markers. In addition, no significant association was observed between fetuin-A and histological findings including liver fibrosis. Conclusion: This study demonstrated that plasma fetuin-A levels are not correlated with the hepatic histology and systemic markers of inflammation in nondiabetic subjects with NAFLD. Our data also suggested that age is significantly associated with fetuin-A in this clinically relevant condition.

Collaboration


Dive into the Muammer Kara's collaboration.

Top Co-Authors

Avatar

Teoman Dogru

University of Valladolid

View shared research outputs
Top Co-Authors

Avatar

Halil Genc

Military Medical Academy

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Serkan Tapan

Military Medical Academy

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Yusuf Yazgan

Military Medical Academy

View shared research outputs
Top Co-Authors

Avatar

Sait Bagci

Military Medical Academy

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge