Fahri Uçar
Karadeniz Technical University
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Publication
Featured researches published by Fahri Uçar.
World Journal of Surgery | 2005
N. Agaoglu; Serdar Turkyilmaz; Ercument Ovali; Fahri Uçar; Celal Ağaoğlu
Acute mesenteric ischemia (AMI) is a rare condition that may be associated with a variety of congenital prothrombotic disorders (PDs). The purpose of this study was to assess the prevalence of these disorders in 28 AMI patients compared with 103 healthy individuals from the northeastern region of Turkey. They were screened for protein C, antithrombin III, and protein S deficiencies; and gene analysis was performed using the polymerase chain reaction. A PD was revealed in 16 (57%) patients and 33 (32%) controls (p = 0.020). Factor V Leiden (FVL), prothrombin G20210A mutation, and TT677 homozygous mutation of methylenetetrahydrofolate reductase was detected in 10 (36%) patients versus 16 (15%) controls (p = 0.035), 3 (11%) patients versus 10 (9%) controls (p = 1.00), and 1 (3%) patient versus no controls, respectively. Consistent with caucasian ethnic groups, there was high prevalence of PDs, especially FVL; and these abnormalities might be a significant predisposing factor in the pathogenesis of AMI.
Clinical Chemistry and Laboratory Medicine | 2001
S. Caner Karahan; Orhan Deger; Asım Örem; Fahri Uçar; Cihangir Erem; Ahmet Alver; Ekin Önder
Abstract Impaired trace element metabolism may be involved in some of the metabolic dysfunctions, and contribute to the development of vascular complications in diabetic patients. In order to investigate the relationships among diabetes mellitus, trace element status, leukocyte activation and vascular complications, 55 type 2 diabetic patients (34 with vascular complications and 21 without vascular complications) and 50 non-diabetic control subjects were studied. The mean leukocyte count (p<0.001), polymorphonuclear elastase (p<0.001), erythrocyte malondialdehyde (p<0.001), and glycated haemoglobin (p<0.001) levels, and copper/zinc ratio (p<0.001) were found to be higher in diabetic patients than in the control group, but serum zinc levels (p<0.001) and erythrocyte superoxide dismutase activities (p<0.001) were lower, and serum copper levels showed no differences. In patients with vascular complications, the mean leukocyte count (p<0.05), zinc (p<0.05), polymorphonuclear elastase (p<0.05), erythrocyte malondialdehyde (p<0.001) and glycated haemoglobin (p<0.05) levels, and copper/zinc ratio (p<0.001) were significantly different from those patients without complications. Closer correlations between the copper/zinc ratio and polymorphonuclear elastase (r=0.82, p<0.01), erythrocyte malondialdehyde (r=0.46, p<0.05) or erythrocyte superoxide dismutase (r= −0.85, p<0.01) were found in patients with vascular complications compared to those without, and all of those showed significant relationships with poor glycaemic metabolic control. We conclude that zinc deficiency may provoke polymorphonuclear leukocyte activation, and contributes to the development of vascular complications in type 2 diabetic patients. Furthermore, copper/zinc ratio and polymorphonuclear elastase may be used as important markers to evaluate the presence of vascular complications.
Clinical Biochemistry | 2011
Ahmet Alver; Ayşe Şentürk; Haşim Çakırbay; Ahmet Mentese; Ferhat Gökmen; E. Edip Keha; Fahri Uçar
OBJECTIVES To investigate the relationship between carbonic anhydrase (CA) II autoantibody and lipid peroxidation, certain antioxidant parameters, and cytokines in rheumatoid arthritis (RA) patients. DESIGN AND METHODS Serum levels of CA II autoantibody, cytokines (TNFα, IL-6, IFN-γ, IL-1β) and bone markers (crosslaps, osteocalcine) and erythrocyte levels of antioxidant enzyme activities (SOD, CAT, GPx), GSH and MDA, and CA activities were measured in RA patients and healthy controls. RESULTS The CA II autoantibody titers were significantly higher (P<0.05), and erythrocyte SOD activities were significantly lower (P<0.05) in RA patients. A significant negative correlation between CA II autoantibody titers and SOD activities in RA group was established (r=-0.430, p=0.006). The elevated cytokine levels could not be correlated with CA II autoantibody levels in RA. CONCLUSION These results suggest that increased erythrocyte oxidative stress observed in RA may be effective in the mechanism of CA II autoantibody formation.
Journal of Enzyme Inhibition and Medicinal Chemistry | 2004
Ahmet Alver; Fahri Uçar; E. Edip Keha; Ersan Kalay; Ercument Ovali
Studies on the biochemical and molecular mechanisms underlying obesity have shown that the expression of some proteins was decreased with obesity in rat adipose tissue. One of these proteins is carbonic anhydrase III (CA III) which constitutes 24% of the cytosolic protein content and its function is unclear. A freshly isolated rat adipose cell culture model was used to examine the effect of leptin and insulin on CA III expression. It was found that leptin decreased CA III expression while insulin increased it which suggests that the decrease in CA III expression observed in obesity in rat adipose tissue may be related to hyperleptinemia.
Transfusion and Apheresis Science | 2003
Ercument Ovali; Siret Ratip; Mehmet Ozmenoglu; S. Sami Karti; Fahri Uçar; Kubilay Ukinc; Mustafa Yilmaz; Polat Koşucu
BACKGROUND Life-threatening complications following apheresis are rare, and include venous thrombosis. Arterial thrombosis following apheresis has not been reported. CASE REPORT A 48 year old donor had cerebral infarction following large volume plasma donation. The outcome was fatal. He was found to be heterozygous for both methylene tetrahydrofolate reductase (MTHFR) 677C-T mutation and Prothrombin 20210G-A allele. CONCLUSION This case suggests that large volume plasma donation may trigger arterial thrombotic events in inherited thrombophilia. Therefore, the effects of plasmapheresis on coagulation system should be studied thoroughly.
Hematology | 2010
Mehmet Sonmez; Fatma Saglam; S. Caner Karahan; Nergiz Erkut; Ahmet Mentese; Bircan Sonmez; Fahri Uçar; Murat Topbas; Ercument Ovali
Abstract Polycythemia vera (PV) is a clonal myeloproliferative disorder characterized by predominantly excessive erythrocyte production. During the course of the disease, bleeding or thrombosis may be observed. In PV patients, the influence of antifibrinolytic activities on development of thrombohemorrhagic complications remains to be elucidated. In the present study, alterations in antifibrinolytic activity of PV patients and the effects of treatments on these alterations were investigated. Newly diagnosed and therapy-naive 22 PV patients were included. Thrombomodulin (TM), plasmin-alpha 2-antiplasmin complex (PAP), plasminogen activator inhibitor-1 (PAI-1) and thrombin activable fibrinolysis inhibitor antigen (TAFIa) levels were measured in all individuals and after phlebotomy and 5-hydroxyurea (5-HU) therapy in PV patients. TM, PAP, PAI-1 and TAFIa values of the patient group were higher than those of the controls. After phlebotomy, no changes were detected in TM, PAI-1 and TAFIa values, but PAP values decreased. On the contrary, 5-HU treatment resulted in a marked decrease in TM, PAI-1, PAP and TAFIa levels. These findings suggested that the changes in antifibrinolytic activity and endothelial dysfunction might be contributed to formation of intravascular thrombosis in PV patients, even though not clinically overt. 5-HU in addition to phlebotomy affects antifibrinolytic activity and may have an influence on diminishing predisposition of thrombosis.
Acta Cardiologica | 2001
Sukru Celik; Ercument Ovali; Merih Baykan; Fahri Uçar; Cevdet Erdöl; Ismet Durmus; Sahin Kaplan
Objective — The genetic defect of coagulation factor V, known as factor V Leiden, produces a resistance to degradation by activated protein C (APC) and increases the risk of venous thrombosis. However, the role of factor V Leiden in the formation of left ventricular (LV) thrombus has not been studied.We investigated whether factor V Leiden is a risk factor for LV thrombus in patients with acute myocardial infarction (AMI). Methods and results — We have analyzed clinical, echocardiographic and biochemical data in 135 consecutive patients (aged 58 ± 13 years; 31 women) with first anterior AMI. Two-dimensional echocardiographic examination was performed on days I, 3, 7, 15 and 30; LV thrombus was detected in 33 (24.4%) of 135 patients with AMI. The study also included 95 control subjects. Healthy age and sex-matched subjects without a personal or family history of ischaemic heart disease, stroke or thromboembolic disease served as a control group. Blood samples from the patients and controls were analyzed for the factor V Leiden mutation by DNA analysis, using the polymerase chain reaction. In addition, concentrations of fibrinogen, von Willebrand factor (vWF), tissue plasminogen activator (t-PA), plasminogen activator inhibitor-I (PAI-1) and D-dimer were measured in 135 patients. There was no significant difference in the prevalence of factor V Leiden between patients and control subjects. The prevalence of the factor V mutation was 9% (3/33) in patients with thrombus, and 7.7% (8/103) in patients without thrombus. The prevalence of factor V Leiden was 7.3% (7/95) in control subjects. No significant differences in plasma fibrinogen (480 ± 195 vs. 444 ± 179 mg/dl, p = 0.6), D-dimer (471 ± 256 vs. 497 ± 293 ng/dl, p = 0.7), vWF (112 ± 18 vs. 103 ± 15%, p = 0.5), PAI-I (26.7 ± 9.8 vs. 28.1 ± 10.2 ng/dl, p = 0.6), and t-PA (19.8 ± 8.7 vs. 17.2 ± 9.1 ng/dl, p = 0.7), levels are found in patients with LV thrombus when compared with those without LV thrombus. Multivariate analyses showed that peak creatine kinase level (p = 0.002) and LV wall motion score index (p = 0.003) were independent predictors of LV thrombus formation. Conclusion — Factor V Leiden mutation is not a risk factor for LV thrombus formation in patients with AMI. (Acta Cardiol 2001; 56(1 ): 1-6)
Acta Cardiologica | 2004
Fahri Uçar; Sukru Celik; Ercument Ovali; Sami Karti; Alper Pakdemir; Mustafa Yilmaz; Ekin Önder
Objective — Within the last few years a number of thrombophilic mutations have been identified. Pre-symptomatic testing for these established genetic risk factors identifies individuals predisposed to a disease and often allows to select suitable prophylactic interventions in time.We investigated wether or not the prothrombin G20210A allele, the factor V Leiden G1691A, and MTHFR C677T allele are risk factors for left ventricular thrombus (LV) in patients with myocardial infarction (AMI) or not. Methods and results — We analysed clinical, echocardiographic and biochemical data in 183 consecutive patients (aged 58 ± 12 years; 34 women) with a first anterior acute myocardial infarction. Two-dimensional echocardiographic examination was performed on days 1, 3, 7, 15, and 30. LV thrombi were detected in 42 (23%) of the 183 patients with acute myocardial infarction.We have used multiplex assays based on PCR and DNA hybridization in microtitre plates for the simultaneous analysis of three mutations (FV Leiden G1691A, prothrombin G20210A, and MTHFR C677T). No significant differences in allele frequencies of FV Leiden G1691A (9.5% vs. 8.5%, p = 0.75), prothrombin G20210A (9.5% vs 7.1%, p = 0.74) and MTHFR C677T (47.6% vs. 50.3%, p = 0.74) were found in patients with LV thrombus when compared with those without LV thrombus. No significant differences in haemostatic factor levels were found in patients with LV thrombus when compared with those without LV thrombus. Conclusion — FV Leiden, prothrombin 20210 variant, and MTHFR mutation are no risk factors for left ventricular thrombus in patients with myocardial infarction.The presence of multiple mutations did not influence the development and outcome of LV thrombus in patients with myocardial infarction. (Acta Cardiol 2004; 59(1): 33-39)
Hematology | 2014
Mehmet Sonmez; Nazli Kazaz; Burcu Yücel; Murat Topbas; Fahri Uçar
Abstract Objectives Bone disease is one of the hallmarks of multiple myeloma (MM). The role of osteoprotegerin (OPG) in the RANK/RANKL/OPG signaling system is well defined in the myeloma bone disease. Polymorphisms of the TNFRSF11B gene encoding OPG have been studied in various bone diseases. However, relationship between the levels of OPG and development of bone lesions regardless of RANKL is yet unknown. In this study, the effects of OPG gene polymorphism on the development of bone lesions in MM were investigated. Methods C950T and C1181G polymorphisms of the OPG gene were studied in 52 MM patients (36 with bone lesions and 16 without bone lesions) and in another 20 control subjects using DNA sequencing. Results 1181 G and 950 T alleles were overrepresented in MM patients having bone lesions. 950 TT/1181 GG haplotype frequency and TT/GG combined haplotype were also higher in MM patients having bone lesions compared to MM patients without bone lesions or to control. Discussion This is the first study searching for the relationship between OPG gene variants C950T (promoter), C1181G (exon 1), and myeloma bone disease. It was concluded that the presence of polymorphic 1181 G/950 T alleles and 950 TT/1181 GG genotypes may play a role in the development of bone disease.
International Journal of Rheumatic Diseases | 2012
Fahri Uçar; Erhan Capkin; Murat Karkucak; Burcu Yücel; Mehmet Sonmez; Ahmet Alver; Nese Kaklikkaya; Mehmet Tosun; Emel Alemdaroğlu; Mustafa Solak
Aim: The aim of this study was to investigate the associations between human leukocyte antigen (HLA)‐DRB1 alleles with genetic susceptibility to rheumatoid arthritis (RA) and production of antibodies against cyclic citrullinated peptide (anti‐CCP antibody) and rheumatoid factor (RF) in Turkish RA patients.