Hakan Ozan
Uludağ University
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Publication
Featured researches published by Hakan Ozan.
Journal of Obstetrics and Gynaecology Research | 2004
Tufan Bilgin; Sema Özuysal; Hakan Ozan; Turkan Atakan
Aim: To investigate the possibility of coexisting endometrial cancer (EC) in patients with atypical endometrial hyperplasia (AEH).
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1997
Yalçın Kimya; Cezmi Akdiş; Candan Cengiz; Hakan Ozan; Serhat Tatlikazan; Gürkan Uncu; Ferah Şengül
Abstract The values of plasma interleukin-1α (IL-1α), interleukin-1β (IL-1β) and interleukin-1 receptor antagonist (IL-1ra) levels were evaluated as the markers of pre-eclampsia in 35 serial plasma samples from ten pregnant women who subsequently developed pre-eclampsia and in 74 plasma samples from 20 uncomplicated pregnancies, retrospectively. No correlation was found between plasma IL-1α, IL-1β and IL-1ra levels, liver and renal function tests. thrombocyte and white blood cell counts, proteinuria, systolic and diastolic blood pressures and gestational weeks. Almost equal levels of IL-1α and IL-1β were measured in all corresponding groups, but these were too few in number to statistically analyze. IL-1ra values were higher in the pre-eclampsia group than in the uncomplicated pregnancy group, at 20–25 and 31–35 gestational weeks significantly and 26–30 gestational weeks insignificantly and showed an increase during labor in both groups. It was found to have 58% positive predictivity, 100% negative predictivity, 50% specificity and 100% sensitivity at gestational weeks 20–25. According to these results, IL-1ra seems to be considered for its high negative predictivity in the exclusion of the probability of pre-eclampsia development during antenatal visits, but its plasma level is not correlated with the severity of the disease.
Journal of Gynecologic Oncology | 2010
Beray Kiran; Mutlu Karkucak; Hakan Ozan; Tahsin Yakut; Kemal Özerkan; Sebnem Ozemri Sag; Mehmet Ture
OBJECTIVE This work investigates the role of glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1), and glutathione S-transferase P1 (GSTP1) enzymes and polymorphisms, which are found in phase II detoxification reactions in the development of cervical cancer. METHODS This study was conducted with 46 patients diagnosed with cervical cancer and 52 people with no cancer history. Multiplex PCR methods were used to evaluate the GSTM1 and GSTT1 gene polymorphism. However, the GSTP1 (Ile105Val) gene polymorphism was studied using a PCR-RFLP method. The patient and control groups were compared using a chi-square test with p<0.05. RESULTS In the patient group, statistical significance was determined for gravidity (p=0.03), parity (p=0.01), and the number of living children (p=0.01) compared to the control group. The gene frequency of GSTM1, GSTT1, and GSTP1 polymorphisms was evaluated. We observed that GSTM1 and GSTT1 null genotype frequencies were 54.3% and 32.6% respectively, while GSTP1 (Ile/Val), (Ile/Ile), (Val/Val) genotype frequencies were 52%, 44%, and 4%, respectively, in the cervical cancer patients. No statistical variation was determined between the control and patient groups in terms of GSTM1, GSTT1, and GSTP1 polymorphisms (p>0.05). CONCLUSION Our results demonstrate that GSTT1, GSTM1, and GSTP1 polymorphisms are not associated with cervical cancer in Turkish patients.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1997
Hakan Ozan; Ahmet Esmer; Nedret Kolsal; Ömer Utku Çopur; Bülent Ediz
An imbalance between oxidants and antioxidants in the circulation is blamed to cause preeclampsia and eclampsia. In this study plasma ascorbic acid level was analysed in 13 eclamptic, 14 mild preeclamptic, 12 severe preeclamptic and 20 uncomplicated pregnancies to see whether there is any correlation with blood pressure, proteinuria, serum triglyceride level, erythrocyte fragility and leukocyte count. Plasma ascorbic acid level was normal and had no significant difference among the groups. Fasting serum triglyceride level was significantly higher in the study group than in the control group but it did not differ among the three study groups. Erythrocyte fragility was found to be increased in all three study groups. Blood leukocyte count was increased in the study groups, especially in the eclampsia group. However, plasma ascorbic acid level and erythrocyte fragility were found to have no significant correlation with blood pressure and proteinuria. It was concluded that though the ascorbic acid levels were normal in both the study and the control groups, erythrocyte fragility increased probably due to an elevation in peroxide and free radical levels in preeclampsia and eclampsia groups, but without any correlation with the severity of the clinical picture.
Journal of Obstetrics and Gynaecology Research | 2002
Hakan Ozan; Yes¸im .Ilçöl; Yalçın Kimya; Candan Cengiz; Bülent Ediz
Objective: To investigate the total plasma anti‐oxidant status, the plasma lipid profile and the uterine artery Doppler velocity waveform in formerly pre‐eclamptic women.
Gynecologic and Obstetric Investigation | 2003
Sema Özuysal; Tufan Bilgin; Hakan Ozan; H. Filiz Kara; Hülya Öztürk; İlker Ercan
Association among angiogenesis, survival and clinicopathologic parameters in endometrial carcinoma was evaluated. Sixty patients who had been diagnosed as endometrial carcinoma, from 1993 to 1998, were included in the study. All patients had been surgically staged with bilateral pelvic and para-aortic lymph node dissection. All hysterectomy specimens were stained immunohistologically for factor VIII-related antigen. The area with the most intensified microvasculature was determined under low-power (×100) magnification, and the microvessel count of this area under high-power (×200) magnification was determined as the microvessel density (MVD) of the tumor. The mean MVD was 26.2 ± 13.0 (range 6–68), and it was considered as high (n = 24; 40%), moderate (n = 19; 31.7%) and low (n = 17; 28.3%) when the MVD was >30, between 15–30 and <15, respectively. Statistical analysis included Mann-Whitney, Kruskal-Wallis and Spearman rank correlation tests. The Kaplan-Meier method was used to evaluate the difference between angiogenesis and survival. Multivariate analysis with the Cox regression model was used in MVD values and different clinicopathological parameters. There was positive correlation between MVD increase and surgicopathological stage (p < 0.05). A significant difference was seen between MVD increase and lymph node metastasis (p < 0.05). There were no differences between MVD and age, histological type, grade and lymphovascular invasion. MVD did not change in association with myometrial invasion depth. There was a significant difference in means of survival between the low and high MVD groups (p = 0.01). However, MVD was not an independent prognostic factor in multivariate analysis. Increased angiogenesis was found to be associated with advanced stage and decreased survival in endometrial carcinoma.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1996
Gürkan Uncu; Hakan Ozan; İsmail Küa̧ükerdoğan; Candan Cengiz
It was suggested that anticardiolipin antibodies (ACA) were found positive in some obstetrical problems such as recurrent foetal losses, intrauterine growth retardation, etc. The aim of this study was to determine ACA levels in pregnancy induced hypertension (PIH) cases. ACA IgG and IgM levels were measured by the ELISA method in 65 PIH cases and 23 control pregnancies. We could not find any difference between the PIH and the control groups. There was not any statistically significant difference between the subtypes of PIH. According to these results, we say that ACA IgG and IgM levels have no diagnostic and prognostic value in PIH.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1993
Mehpare Tüfekçi; Zafer Colak; Hakan Ozan; Yalçın Kimya; Ali Aydinlar
A study was performed to evaluate the role of progestogens, on estrogen-induced changes in lipoprotein levels. Sixty postmenopausal symptomatic women, aged 36-59, were included in the study. They were prospectively randomized to a sequential schedule (n = 20), 17 beta-estradiol transdermally 0.05 mg/day on days 1-24 and medroxyprogesterone acetate 10 mg/day orally on days 15-24 or a continuous schedule (n = 20), 17 beta-estradiol transdermally 0.05 mg/day and medroxyprogesterone acetate 2.5 mg/day orally on days 1-24. Patients who had total abdominal hysterectomy+bilateral salphingooopherectomy (n = 20) received only 17 beta-estradiol 0.05 mg/day continuously. Serum total cholesterol (TC), high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol and triglyceride (TG) levels were determined prior to and at the 3rd, 6th and 9th month of therapy in all groups. Mean TC, TG and LDL cholesterol levels did not change significantly during therapy (P > 0.05). Only the mean HDL cholesterol levels showed significant increases in all groups; from 42.30 +/- 9.97 mg/dl to 64.10 +/- 6.81 mg/dl in group I (P < 0.001), from 41.85 +/- 9.09 mg/dl to 60.65 +/- 7.41 mg/dl in group II (P < 0.001) and from 40.70 +/- 11.26 mg/dl to 58.80 +/- 7.74 mg/dl in group III (P < 0.001). It is concluded that medroxyprogesterone acetate, whether used continuously or sequentially, does not oppose the beneficial effects of transdermal 17 beta-estradiol on the lipoprotein profile.
Gynecological Endocrinology | 2012
İbrahim Alanbay; Erhan Aktürk; Hakan Coksuer; Mutlu Ercan; Emre Karasahin; Murat Dede; Müfit Cemal Yenen; Hakan Ozan; Iskender Baser
Objective: The aim of this study was to assess the prognostic values of risk of malignancy index (RMI IV), ultrasound score, menopausal status, and serum CA125 and CA19-9 level in patients with borderline ovarian tumor (BOT). Methods: Fifty women having borderline ovarian tumor (BOT) and 5O individuals with benign adnexal mass were enrolled in this retrospective study. The sensitivity, specificity, positive predictive values, negative predictive values and diagnostic accuracy of preoperative serum levels of the CA125 and CA19-9, ultrasound findings and menopausal status, and RMI IV were calculated for prediction of discrimination between BOTs and benign adnexal masses and the results were compared. Results: The RMI IV was the best method for discrimination between BOTs and benign adnexal masses and was more accurate than the other parameters. When Receiver Operator Characteristic area under the curves for menopausal status was analyzed, serum CA 125 and CA19-9 level, ultrasound score, RMI IV(CA125), and RMI IV(CA19-9) were, 0.580, 0.625, 0.548, 0.694, 0.734 and 0.711, respectively. The best RMI IV cut-off was found to be 200 for discrimination of benign and BOT lesions. In the RMI formulation, replacing CA125 with CA19-9 didn’t affect RMI IV sensitivity and specificity for discrimination. Conclusion: Compared to ultrasound, menopausal status, CA-125, CA19-9, the RMI IV was found to be the best predictive method for differentiation of BOTs from benign adnexal masses. RMI IV cut–off value of 200 is suitable for differentiation of benign and BOT’s.
Archives of Gynecology and Obstetrics | 2005
Tufan Bilgin; Sema Özuysal; Hakan Ozan
MethodsTo compare the architectural, nuclear and International Federation of Gynecology and Obstetrics (FIGO) grading systems in endometrial cancer 70 consecutive patients with endometrial cancer were retrospectively reevaluated with three grading systems. ResultsTwenty-eight (40%), 27 (38.6%) and 14 (20%) cases were reported to have different grades when architectural vs nuclear, architectural vs. FIGO and nuclear vs. FIGO grading systems were compared in evaluation, respectively. Only 3 (42.8%) of the seven died patients had grade 3 in all three grading systems. Five-year survival rates were 95.7, 80, and 78.6% for architectural grade 1, 2 and 3, respectively. Same rates were 96.7, 90.5, and 78.9% for nuclear and 96, 91.7 and 81% for FIGO grading systems, respectively.ConclusionsGrades of the tumors often change when different grading systems are used. Postoperative treatment should be considered when at least one of the grading systems indicates poor differentiation.