Karatoprak, O | Karaali, ZE | Incekara, K | Celik, F | Zeybek, U | Ergen, HA | İşbir, Turgay

Article | 2013 | TURKISH JOURNAL OF BIOCHEMISTRY-TURK BIYOKIMYA DERGISI38 ( 2 ) , pp.186 - 192

Objective: The ABCB1/MDR1 is a 170-kDa transporter protein called P-glycoprotein (P-gp) which has been associated with the transport of cellular lipids and drugs. Recent studies focused on MDR1, and its effects on lipid transport, show that the constitutive expression of P-gp transporter in normal tissues plays an important role in drug disposition and response. In addition, it is known that some polymorphisms on the MDR1 gene alter the expression of the P-gp. This study aims to investigate the effects of the MDR1 C3435T and the C1236T gene polymorphisms on the dyslipidemia of diabetic patients. Material and methods: The PCR-RFLP me . . .thod has been used on 77 patients and 75 controls in order to determine the MDR1 genotype. Results: There are no statistical differences for the MDR1 C3435T and the C1236T genotype ranges among between our inspected groups. However, the C1236T mutant type T allele ratio increases statistically in the patient group (p = 0.026 OR: 1.679 % 95 CI: 1.062 - 2.652). A weak connection has been observed between the MDR1 C3435T C and the C1236T C alleles, according to the linkage disequilibrium analysis. Conclusion: This study is one of the preceding studies, which examines the relationship between MDR1 polymorphisms and type 2 diabetes. Studies on MDR1 genotypes, and their effects on lipid levels are new in literature, hence our study proves to be unique when it comes to both the C3435T and the C1236T polymorphisms in type 2 diabetes patients; however, further research is still needed for the confirmation of our findings Daha fazlası Daha az

Kirac, D | Erdem, A | Gezmis, H | Yesilcimen, K | Altunok, EC | İşbir, Turgay

Article | 2018 | CLINICAL AND EXPERIMENTAL HEALTH SCIENCES8 ( 1 ) , pp.1 - 8

Objective: This study aimed to investigate the relationship between genetic and environmental factors that are believed to have an effect on stent thrombosis (ST) in coronary artery disease (CAD) patients after stent implantation. Methods: Seventy-three CAD patients who were implanted with stents by surgical intervention were enrolled. Thirty-seven patients with ST were included in the patient group, and 36 patients without ST were included in the control group. After obtaining necessary information from the patients, DNA was isolated from blood. Rs2228570 and rs1544410 mutations in the vitamin D receptor (VDR) gene as well as rs458 . . .8 and rs7041 mutations in the vitamin D-binding protein (VDBP) gene were investigated by performing real-time polymerase chain reaction. Biochemical measurements, such as those of vitamin D and lipid levels, were performed using appropriate kits. Results were evaluated using statistical methods. Results: The number of individuals who carry homozygous or heterozygous alleles of the rs4588 mutation in the VDBP gene was found to be statistically high in the patient group (p=0.027). Vitamin D and hemoglobin levels were significantly low and C-reactive protein levels were significantly high, while the occurrence of vitamin D deficiency, hypertension, and familial history of CAD as well as the current status of smoking were significantly high in the patient group ( Daha fazlası Daha az

Kucukhuseyin, O | Toptas, B | Timirci-Kahraman, O | Isbir, S | Karsidag, K | İşbir, Turgay

Conference Object | 2013 | FEBS JOURNAL280 , pp.349 - 349

…

Yildiz, Y | Yaylim-Eraltan, I | Arikan, S | Ergen, HA | Kucucuk, S | İşbir, Turgay

Article | 2010 | ARCHIVES OF MEDICAL SCIENCE6 ( 6 ) , pp.932 - 936

Introduction: TNF-related apoptosis-inducing ligand (TRAIL) is a death ligand and also a member of the TNF superfamily. We aimed to investigate the possible relationship between TRAIL and breast cancer. Here, we report the results of the first association study on genetic variation in the TRAIL gene and its effect on breast cancer susceptibility and prognosis. Material and methods: A C/T polymorphism at 1595 position in exon 5 of the TRAIL gene was genotyped in a Turkish breast cancer case-control population including 53 cases (mean age: 55.09 +/- 11.63 years) and 57 controls (mean age: 57.17 +/- 17.48 years) using polymerase chain . . .reaction restriction fragment length polymorphism (PCR-RFLP) analysis. Results: There were no differences in the distribution of TRAIL genotypes and frequencies of the alleles in the breast cancer patients and controls. A heterozygous TRAIL CT polymorphism in exon 5 was present in 8.3% of tumour stage III-IV and 48.8% of stage patients, and in 42.1% of controls. The reduced frequency of this genotype in patients who had advanced tumour stage was statistically significant (p = 0.017). Conclusions: Our findings indicate that genetic variants of TRAIL at position 1595 in exon 5 might be associated with progression of breast cancer Daha fazlası Daha az

Attar, R | Yildirim, G | Ficicioglu, C | Gulec-Yılmaz, S | Timirci-Kahraman, O | Atasoy, H | İşbir, Turgay

Conference Object | 2014 | ANTICANCER RESEARCH34 ( 10 ) , pp.5966 - 5967

…

Kirac, D | Eraydin, F | Avcilar, T | Ulucan, K | Ozdemir, F | Guney, AI | İşbir, Turgay

Conference Object | 2018 | EUROPEAN JOURNAL OF HUMAN GENETICS26 , pp.476 - 476

…

Ol, KK | Agachan, B | Gormus, U | Toptas, B | İşbir, Turgay

Article | 2011 | GENETICS AND MOLECULAR RESEARCH10 ( 2 ) , pp.810 - 816

Coronary artery disease is one of the leading causes of mortality and diabetes mellitus is one of its main risk factors due to microvascular and macrovascular complications, such as atherosclerosis. Atherosclerosis is now known to be an inflammatory process mediated by prostaglandins and several interleukins. As both are important in inflammatory processes, we examined Cox-2 (-765G > C) polymorphism and interleukin-6 levels in coronary artery disease patients compared to healthy controls. We also divided the patients into diabetic and nondiabetic groups to check the effects of diabetes mellitus separately. We found that the GG allel . . .e frequency was significantly higher in the patient group. Patients with the GG genotype had an approximately 2.78-fold higher risk of coronary artery disease. We also found that the Cox-2 (-765G > C) polymorphism is associated with lower interleukin-6 levels, which decreased in the order: GG > GC > CC Daha fazlası Daha az

Gurdol, F. | Cakmakoglu, B. | Dasdemir, S. | Isbilen, E. | Bekpinar, S. | İşbir, Turgay

Article | 2012 | Genetic Testing and Molecular Biomarkers16 ( 5 ) , pp.435 - 438

Cyclooxygenase-2 (COX-2) is the inducible isoenzyme of COX that leads to increased production of prostaglandins and thromboxane, the mediators of inflammation. Controversial data regarding COX levels or activities in the placentas of women with preeclampsia have led us to examine whether a single nucleotide polymorphism (SNP) in the COX-2 gene is associated with the onset of preeclampsia. Two polymorphisms in the promoter region of COX-2 gene were examined by the polymerase chain reaction and restriction fragment length polymorphism in 128 controls and 74 preeclamptic patients. Genotype distribution and allelic frequencies for-765G› . . .C polymorphism of COX-2 gene were significantly different between patients and controls (p=0.000 and p=0.042, respectively). The odds ratio (OR) for preeclampsia risk associated to the-765G allelic variant was 4.07 (95% confidence interval [CI]: 0.89-18.56). The AA genotype of the-1195 A›G variant was present at a significantly higher frequency among all preeclamptic subjects (p=0.000 ?2: 13.4, OR: 3.44, 95% CI: 1.74-6.77). A moderate linkage was observed between the-765G and-1195A variants (D0: 0.201; r2: 0.003). These findings suggest that SNPs,-765G›C and-1195 A›G, on the promoter region of COX-2 gene may reduce the risk of preeclampsia, possibly by affecting the rate of gene expression. © 2012 Mary Ann Liebert, Inc Daha fazlası Daha az

Kurt, O | Aydogan, HY | İşbir, Turgay | Uyar, M | Can, A

Conference Object | 2010 | DRUG METABOLISM REVIEWS42 , pp.254 - 254

…

İşbir, Turgay | Gormus, U. | Dalan, A.B.

Book Part | 2013 | Brenner's Encyclopedia of Genetics: Second Edition , pp.22 - 23

The term 'favism' is used to indicate a severe reaction occurring on ingestion of foodstuffs consisting of or containing the beans of the leguminous plant Vicia faba (fava bean, broad bean). Within 6-24. h of the fava bean meal, the reaction manifests itself with prostration, pallor, jaundice, and dark urine. These signs and symptoms result from (sometimes massive) destruction of red blood cells (RBCs; acute hemolytic anemia), triggered by certain glucosides (divicine and convicine) present at high concentrations in the fava beans. These glucosides cause severe damage to RBCs only if the cells are deficient in the enzyme glucose-6-p . . .hosphate dehydrogenase (or G6PD); therefore, favism occurs only in people who have inherited G6PD deficiency. Favism is more common and more life-threatening in children (usually boys) than in adults; however, once the attack is over, a full recovery is usually made. In a person who is G6PD deficient, favism can recur whenever fava beans are eaten, although whether this happens or not is greatly influenced by the amount of beans ingested and probably by many other factors. From the public health point of view, it has been proven that favism can be largely prevented by screening for G6PD deficiency and by education through the mass media. © 2013 Elsevier Inc. All rights reserved Daha fazlası Daha az

Cacina, C. | Yaylim-Eraltan, I. | Arikan, S. | Saglam, E.K. | Zeybek, U. | İşbir, Turgay

Article | 2010 | In Vivo24 ( 2 ) , pp.179 - 183

Background: CDKN1A (p21WAF1/CIP1) plays an important role in cell cycle regulation. Somatic alterations in genes which regulate cell division have been shown to be related to different types of cancer prognosis and survival. The purpose of this study was to investigate the effect of the CDKN1A Ser31Arg and C20T gene polymorphisms in Turkish patients with colorectal cancer. Patients and Methods: CDKN1A Ser/Arg and C20T polymorphisms were studied in 53 patients with colorectal cancer and 64 healthy controls. Genomic DNA was amplified by polymerase chain reaction (PCR) and genotypes were determinated by the restriction fragment length . . .polymorphism (RFLP) method. Results: There were statistically significant differences in the distribution of CDKN1A Ser/Arg genotypes and allele frequencies between colorectal cancer patients and healthy controls (p=0.040 and p=0.01, respectively). CDKN1A C20T genotype frequency did not show any significant differences between patients and controls. We combined the results for C20T and Ser31Arg polymorphisms and observed that a lower risk of colorectal cancer was associated with CT/SerArg combined genotypes compared to controls and this difference was statistically significant (p=0.024; odds ratio (OR)=0.322, 95% confidence interval (CI)=0.114-0.912). C20T C allele and SerSer genotypes significantly increased risk compared to other combined genotypes (p=0.034; OR=1.265, 95% CI=1.020-1.569). Conclusion: The results of present study demonstrated that, potentially, CDKN1A functional polymorphisms may contribute to the risk of colorectal cancer in Turkish Daha fazlası Daha az

Ozdogan, S. | Kafadar, A. | Yilmaz, S.G. | Timirci-Kahraman, O. | Gormus, U. | İşbir, Turgay

Article | 2017 | Anticancer Research37 ( 9 ) , pp.4997 - 5000

Background/Aim: This study is the first to evaluate the relationship of caspase-9 (CASP-9) gene polymorphism with the risk for primary brain tumor development. Materials and Methods: The study group included 43 glioma and 27 meningioma patients and 76 healthy individuals. CASP-9 gene Ex5+32 G>A (rs1052576) polymorphism was analyzed by real-time polymerase chain reaction (RT-PCR). Results: Individuals with the CASP-9 GG genotype had significantly decreased risk of developing a glioma brain tumor (p=0.024). Additionally, the GA genotype was significantly lower in patients with glioma than the control group (p=0.019). A significantly d . . .ecreased risk of developing glioma was found in the A allele carrier group (p=0.024). However, there was no statistically significant relationship between CASP-9 polymorphism and brain meningioma (p=0.493). Conclusion: CASP-9 (rs1052576) mutant A allele seems to be a protective factor for glioma brain tumor. Future studies with a larger sample size will clarify the possible roles of CASP-9 gene in the etiology and progression of primary brain tumors Daha fazlası Daha az