Orhan Ayyildiz
Dicle University
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Featured researches published by Orhan Ayyildiz.
Amyloid | 2008
Semi˙r Pasa; Abdullah Altintas; Bi˙lge Devecioglu; Ti˙muci˙n Cil; Ramazan Danis; Hi˙lmi˙ Isi; Kadi˙m Bayan; Yekta Tüzün; Sultan Ecer; Sabri Batun; Orhan Ayyildiz
Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurrent inflammatory attacks of serosal membranes. Several studies have focused on the differences between frequency of the mutations and their phenotypical manifestations. The aim of this study was to evaluate whether or not this phenotypical variation is associated with the existence of particular mutations. Twelve MEFV (Mediterranean fever) gene mutations were investigated in 119 patients suffering from FMF. Heterozygote M694V (21/119), heterozygote E148Q (21/119), homozygote M694V (17/119) and heterozygote V726A (12/119) mutations were the most common mutations. Patients were grouped according to the presence of the M694V mutation: group I was M694V/M694V, group II was M694V/others, and group III was other/other. Mean severity scores for the groups were 13.94 ± 4.10, 10.79 ± 3.01 and 8.31 ± 2.26, respectively. There were statistically significant differences between the mean severity scores of groups I and II (p = 0.029), groups I and III (p < 0.0001), and groups II and III (p < 0.0001). Diagnosis of amyloidosis was established in four (23%) patients of group I, and three (8%) patients of group II, but in none of the patients in group III. There was also a statistically significant difference between groups I and III (p = 0.046), but not between groups II and III (p = 0.083) and groups I and II (p = 0.317) in terms of amyloidosis development. In conclusion, we found a higher disease severity score and higher prevalence of amyloidosis in FMF patients who were M694V mutation carriers. Many ethnic groups live in Anatolia and more ethnic origin-based studies are needed to determine the real effect of these mutations on disease severity and amyloidosis.
Annals of Hematology | 2007
Abdullah Altintas; Semir Pasa; Nurten Akdeniz; Timucin Cil; Murat Yurt; Orhan Ayyildiz; Sabri Batun; Hilmi Isi
Factor V Leiden (FV-Leiden) and prothrombin gene mutations (FII G20210A) are well-established independent risk factors for thrombosis. In the recent years, many studies have suggested that these mutations are associated with an increased risk of recurrent pregnancy loss (RPL). We aimed to investigate the prevalence of these molecular defects in subjects with a history of early RPL. One hundred and fourteen women with three or more consecutive unexplained first-trimester miscarriages were compared to 185 parous women with uncomplicated pregnancies from the same ethnic origin. The presence of FV-Leiden and FII G20210A mutations was assessed by polymerase chain reaction analysis. Overall, 11 out of the 114 women with early RPL (9.6%) had either FV-Leiden or FII G20210A mutation, as compared with 16 out of the 185 women with normal pregnancies (8.6%; p = 0.756). The prevalence of FV-Leiden mutation was 7.9% (9/114) in patient group, compared with 7% (13/185) in control group (p = 0.780). One hundred and two patients were primary and 12 were secondary aborters. All FV-Leiden positive cases were primary aborters (8.8%; 9/102, p = 0.584). Concerning the FII G20210A, two out of 114 (1.7%) were first-trimester RPL (primary aborters) and three out of 185 (1.6%) controls were carriers of the FII G20210A mutation (1.7 vs 1.6%, p = 0.931). The results obtained from patients with first-trimester RPL and the control group have no statistical significant differences in the prevalence of FV-Leiden and FII G20210A mutations. These results suggest that mutations have no role in etiology of first-trimester recurrent abortions.
Journal of Neuro-oncology | 2007
Abdullah Altintas; Timucin Cil; İlhan Kılınç; Muhammet Ali Kaplan; Orhan Ayyildiz
SummaryChronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by a reciprocal translocation between chromosomes 9 and 22. Imatinib mesylate is a potent and selective inhibitory of the BCR/ABL tyrosine kinase. Imatinib is a first choice of treatment of chronic phase CML. It has also shown activity in patients with CML in accelerated or blastic phases. However, the penetration of the drug and its active metabolites into the central nervous system (CNS) is poor. Therefore, the CNS is sanctuary site for malignant cells in patients treated with imatinib. Herein, we report a patient with CML in accelerated phase that developed central nervous system disease while on imatinib mesylate therapy.
Electro- and Magnetobiology | 2000
Süleyman Daşdagˇ; M. Zülküf Akdagˇ; Orhan Ayyildiz; Omer Can Demirtas; Murat Yayla; Cemil Sert
The present study aimed to investigate the effects of microwaves (MW) emitted by cellular phones (CPs) on peripheral blood parameters and birth weights of rats. Thirty-six albino rats were divided into four groups, male (n = 6) and female sham-exposed groups (n = 12) and male (n = 6) and female experimental groups (n = 12). No blood parameters differed following exposure (p > 0.05). The birth weight of offspring in the experimental group was significantly lower than in the sham-exposed group (p < 0.001). No significant differences were observed between rectal temperatures of rats in the sham and experimental groups (p > 0.05). The specific absorption rate (SAR) was found to be 0.155 W/kg for the experimental groups. All parameters investigated were normal in the next generation of rats (p > 0.05).
Leukemia & Lymphoma | 2007
Abdullah Altintas; Zülküf Karahan; Semir Pasa; Timucin Cil; Taylan Boyraz; Kenan Iltumur; Orhan Ayyildiz
Increased incidence of pulmonary hypertension (PH) has been reported in patients with chronic myeloproliferative disorders. The exact incidence of PH in essential thrombocythemia (ET) is unknown. Most of the reported literature consists of case reports or small studies. We designed this study to asses the incidence of PH in patients with ET and reactive thrombocytosis. Previously or newly diagnosed 46 patients with ET, and 40 patients with reactive thrombocytosis secondary to iron deficiency anemia were found to be eligible for this study. Diagnosis of PH was established via transthoracic echocardiography. PH was found in 22 (47.8%) out of 46 patients with ET. Seven patients with PH were newly diagnosed ET, 5 patients with PH were in low, and the other patients with PH were in intermediate or high risk category. We found statistically significant difference in terms of platelet counts between ET patients with PH and without PH (p = 0.027). None of the patients with reactive thrombocytosis had PH. In conclusion, PH appears to be common in patients with ET. Therefore, all patients with ET should be evaluated for PH. Larger and prospective studies are required to clarify the long-term impact of PH on the survival of these patients. Future studies are also needed to determine whether cytoreductive treatment and aspirin prevent the development of PH, and to determine the effects of cytoreductive treatments and aspirin on the prognosis of PH. The effect of PH on ET prognosis should also be determined in low risk ET patients.
Platelets | 2008
Abdullah Altintas; Semir Pasa; Timucin Cil; Kadim Bayan; Deniz Gokalp; Orhan Ayyildiz
The association of chronic idiopathic thrombocytopenic purpura (cITP) and thyroid autoimmune diseases (TAD) is a known but an uncommon condition. Celiac disease (CD), which is characterized by malabsorption and villous atrophy that occur as a consequence of the ingestion of wheat gluten may also be related to other autoimmune disorders. In this study, we investigated the prevalence of thyroid anti-microsomal (TAMA) and anti-thyroglobulin (TATA) auto antibodies, anti-gliadin (AGA) IgG, IgA, anti-endomisium (EMA) IgG and IgA antibodies in 74 patients with cITP and in 162 healthy controls. TATA positivity was found in 29, and TAMA positivity in 19 out of 74 patients; and in 16 and 18 out of 162 controls respectively (p < 0.0001 and p = 0.005, respectively). TAD was diagnosed in 29 of cITP patients. AGA IgG positivity was found in 17, and IgA was present in five out of 74 patients; and AGA IgG was found in 19, and IgA was detected in 4 out of 162 controls (p = 0.032 and p = 0.143, respectively). EMA IgG positivity was found in six out of 74 patients and in nine out of 162 control subjects (p = 0.566). EMA IgA positivity was found in two out of 74 patients and in one out of 162 controls (p = 0.232). We showed that the prevalence of TAD and related autoantibodies are higher in patients with cITP. We suggest that, patients with cITP should be followed up for development of TAD. In addition, all CD related auto antibodies were found to be more frequent in patients with cITP, but only the AGA IgG reached to the clinical significance. None of the CD related auto antibody positive patients developed clinically manifested CD. Large-scale designed studies are needed to clarify the long-term impact and importance of these CD related auto antibodies in patients with cITP.
Heart and Vessels | 2002
Omer Cakir; Orhan Ayyildiz; Ahmet Oruc; Nesimi Eren
Abstract Protein C and protein S deficiencies increase the risk of thromboembolic events. We report a case of combined protein C and S deficiency in a young woman, with resulted in acute myocardial infarction and asymptomatic jugular vein thrombosis. The patient was treated successfully with coronary artery hypass graft surgery and systemic anticoagulation. Our report emphasizes that a combined deficiency of protein C and S may be a high risk factor for arterial thromboembolic events in young adults.
Heart and Vessels | 2004
Orhan Ayyildiz; Sevgi Kalkanli; Sabri Batun; Mehmet Aybak; Abdurrahman Isikdogan; Naci Tiftik; Zahit Bolaman; Murat Söker; Ekrem Muftuoglu
Venous thrombosis (VT) is a common disease, with an annual incidence in the general population of approximately 1 per 1000. The prevalence of genetic risk factors for thrombosis varies greatly in different parts of the world. Prothrombin G20210A (PT G20210A) gene mutation has been recently identified as a common risk factor in venous thrombosis. Sixty-one patients with VT, differing in age and sex, and 340 healthy subjects were consecutively enrolled into our study to determine the prevalence of PT G20210A in VT and in the healthy population of the southeast of Turkey. The mutation was identified with fluorescence resonance energy transfer (FRET) with the LightCycler polymerase chain reaction. The PT G20210A mutation was found to be 6.5% (4/61) in the VT group and 1.2% (4/340) in the healthy group (P = 0.021). Three patients with VT had a heterozygous PT G20210A mutation, and the other patient with VT had both Factor V Leiden and PT G20210A mutations. We showed that this method may be used safely for detection of the PT G20210A gene mutation, and the prevalence of PT G20210A mutation is significantly higher in patients with VT than in the healthy population in the southeast of Turkey.
Leukemia & Lymphoma | 2003
Abdurrahman Isikdogan; Orhan Ayyildiz; Mehmet Dursun; Naci Tiftik; Sabri Batun; Ekrem Muftuoglu
Hepatitis C virus (HCV) has been associated with several extrahepatic disorders including mixed cryoglobulinemia (MC), autoimmune thyroiditis, Sjogrens syndrome. Such associations have led to the suggestion that HCV may participate in the development of various immunmediated disorders. Recently, it has been hypothesised that HCV might act as a trigger for the development of monoclonal B-cell disorders such as non-Hodgkins lymphoma (NHL). Discordant data have been reported in different geographic regions of the world. The aim of this prospective case-control study was to detect the prevalence of HCV in patients with NHL in southeastern Anatolia region of Turkey. In this study, HCV antibody prevalence and cryoglobulinemia were investigated in 119 patients with histologically diagnosed NHL. The control group consisted of 117 patients who visited the outpatient clinic of internal medicine. None of the patients had HCV antibody positive (0%) with the enzyme immunoassay and reverse transcriptase polymerase chain reaction (RT-PCR). One of the control patients had positive HCV antibody (0.9%). Our data does not support the association between HCV infection and NHL in southeastern Anatolia region of Turkey.
Angiology | 2006
Sevgi Kalkanli; Orhan Ayyildiz; Naci Tiftik; Sabri Batun; Abdurrahman Isikdogan; Hakan Ince; Selahaddin Tekes; Ekrem Muftuoglu
Venous thrombosis (VT) is a common disease, with an annual incidence in the general population of approximately 1 per 1,000. Factor V Leiden mutation (G1691A) (FVL) is the most common risk factor in venous thrombosis. The prevalence of FVL for thrombosis varies greatly in different regions of the world. FVL mutation has been identified both by conventional method and fluorescence resonance energy transfer (FRET) with the LightCycler. Sixty-one patients with VT, different in age and sex, were consecutively entered into this study to assess the prevalence of FVL in VT in southeast Turkey. FVL mutation was found in 24.6% (15/61). Fourteen individuals were heterozygous and 1 homozygous, a rate of 22.9% and 1.6%, respectively. In conclusion, the authors suggest that FVL mutation is common in patients with venous thrombosis in southeast Turkey.