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Dive into the research topics where Tunç Ozan is active.

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Featured researches published by Tunç Ozan.


Türk Üroloji Dergisi/Turkish Journal of Urology | 2015

Comparison of retrograde intrarenal surgery and percutaneous nephrolithotomy for the treatment of renal stones greater than 2 cm.

Orhan Karakoç; Ahmet Karakeçi; Tunç Ozan; Fatih Firdolas; Cihat Tektaş; Şehmus Erdem Özkarataş; Irfan Orhan

OBJECTIVE To evaluate the safety and efficacy of retrograde intrarenal surgery (RIRS) in the treatment of kidney stones greater than 2 cm and to compare its results with those of percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS We retrospectively analyzed a total of 143 patients: 86 patients (53 males and 33 females) who underwent PCNL and 57 patients (37 males and 20 females) who underwent RIRS between October 2009 and October 2013. RESULTS The mean duration of operation was 100.26±33.26 min in the RIRS group and 75.55±21.5 min in the PCNL group (p<0.001). The hospital stay was significantly shorter in the RIRS group (1.56±0.8 vs. 4.57±2.1 days in the RIRS and PCNL groups, respectively; p<0.001). Stone-free rates after one session were 66.6% and 91.8% of the RIRS and PCNL groups, respectively. The stone-free rate of the RIRS group improved to 87.7% after the second session. Blood transfusions were required in two patients in the PCNL group. Complication rates were higher in the PCNL group. CONCLUSION This study revealed that RIRS can be an alternative to PCNL in the treatment of kidney stones with a diameter of 2-4 cm especially in patients with comorbidities.


World Journal of Urology | 2013

Evaluation of sexual function in women at two stages of multiple sclerosis

Fatih Firdolas; Tunç Ozan; Rahmi Onur; Serpil Bulut; Irfan Orhan

PurposeIn the present study, we aimed to evaluate the sexual function in patients with multiple sclerosis (MS) who were examined in two subgroups and compare the results to the control group with a validated questionnaire.MethodsA total of 23 consecutive female MS patients divided into groups with relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS) and 45 healthy control subjects were included into the study. The inclusion criteria were as follows: Definite MS, age between 18 and 60 years and an Expanded Disability Status Scale (EDSS) score of <8. The neurologic impairment, the disability and the independence of the patient, and cognitive performances were measured, and also the effect of MS is evaluated by EDSS.ResultsNo statistically significant difference was found between two groups. FSFI scores in both groups were significantly lower than the control group. Domain scores for desire, arousal, orgasm, pain, lubrication and satisfaction measured between RRMS and SPMS patients showed no significant difference. Comparing each domain score for arousal, orgasm and satisfaction revealed significantly lower scores in RRMS and SPMS patients compared to control group.ConclusionsIn this study, we detected statistically significant decrease in FSFI scores in two groups of MS compared to healthy controls. We could not define a difference in sexual function in different stages of MS in women and a statistically significant negative correlation between EDSS and FSFI scores in the two subgroups of MS.


Urology | 2013

Second Pathways in the Pathophysiology of Ischemic Priapism and Treatment Alternatives

Ahmet Karakeçi; Fatih Firdolas; Tunç Ozan; Ihsan Unus; Mehmet Sezai Ogras; Irfan Orhan

OBJECTIVE To evaluate the early therapeutic alternatives such as bosentan, an endothelin receptor blocker, theophylline, an adenosin receptor blocker, and a nonselective phosphodiesterase enzyme inhibitor, zinc protoporphyrin (ZnPP), a heme oxygenase 1 inhibitor, for the therapy of ischemic priapism in the rat models. METHODS Twenty-four Sprague-Dawley rats were randomly divided into 4 equal groups: control group, ZnPP group, bosentan group, and theophylline group. Erection was provided by vacuum constriction method and maintained for 4 hours for achieving the priapism in all groups. The rats in the control group were administered 1 mL/kg saline intraperitoneally (ip). The rats in group 2 were administered 25 mg/kg ZnPP ip. The rats in group 3 were administered 0.25 mg/kg bosentan ip. The rats in group 4 were administered 100 mg/kg theophylline ip. Six rats from each group were decapitated after 6 hours of drug administration. Then endothelin 1, adenosine deaminase, heme oxygenase 1 enzymatic activity, and apoptosis index in the cavernous tissues were estimated. RESULTS Cavernous tissue endothelin 1, adenosine deaminase, heme oxygenase 1 enzymatic activity levels, and apoptosis index were significantly decreased in bosentan, theophylline, and ZnPP-treated rats compared with the controls. CONCLUSION Inhibition of priapism induced apoptosis with bosentan, theophylline, and ZnPP seems promising on preserving erectile function.


Türk Üroloji Dergisi/Turkish Journal of Urology | 2015

Role of percutaneous posterior tibial nerve stimulation either alone or combined with an anticholinergic agent in treating patients with overactive bladder.

Sadık Kızılyel; Ahmet Karakeçi; Tunç Ozan; Ihsan Unus; Osman Barut; Rahmi Onur

OBJECTIVE To evaluate the efficacy of percutaneous tibial nerve stimulation (PTNS), either alone or combined with an anticholinergic agent, in treating patients with an overactive bladder (OAB) in whom previous conservative treatment failed. MATERIAL AND METHODS In this study, we included a total of 30 female patients with OAB in whom all conventional therapies failed between January 2010 and April 2011. Patients were randomly divided into three groups: Group 1, PTNS group; Group 2, patients receiving an anticholinergic agent; and Group 3, patients receiving both PTNS and anticholinergic agent. PTNS treatment continued for 12 weeks with each session lasting 30 min. RESULTS All parameters of the bladder diary significantly improved in all groups (p<0.05). Similarly, all scores measured by questionnaires (UDI-6, IIQ-7, and OABSS) revealed significant improvements in all groups. When the improvements in symptoms were compared among the groups, there was a statistically significantly higher improvement in groups 1 and 3 than in Group 2. CONCLUSION PTNS is a safe, simple, and minimally invasive treatment modality in patients with OAB, and it may be suggested either alone or in combination with anticholinergics when conventional treatments fail.


Urology | 2010

Effects of Combined Use of Trospium Chloride and Melatonin on In Vitro Contractility of Rat Urinary Bladder

Rahmi Onur; Mete Ozcan; Uğur Oktay Tuygun; Tunç Ozan; Ahmet Ayar; Irfan Orhan

OBJECTIVES To examine the effects of combined use of trospium chloride and melatonin on in vitro contractility of rat urinary bladder. METHODS Isolated bladder strips from 20 male Wistar rats were examined in an organ bath. Contractions were evoked by acetylcholine (ACh). Initially, effective concentrations of trospium and melatonin to inhibit the contractions were determined. We subsequently tested the effects of combined use of melatonin and trospium on agonist-induced contractions. RESULTS Exposure of bladder strips to 10 microM ACh significantly increased the contractions. After cumulative administration of increasing concentrations of trospium (1, 3, and 5 microM), agonist-induced contractions decreased significantly (P <.05). Similarly, the mean peak amplitude of contractions evoked by ACh was significantly inhibited by melatonin in a concentration-dependent manner (100, 200, and 300 microM) (P <.05). Further evaluation of the effects of combined use of trospium and melatonin on ACh-induced contractions of bladder strips revealed that one-tenth of initially applied dose of trospium (500 nM) in addition to the lowest inhibitory dose of melatonin (100 microM) significantly lowered both the peak amplitude and area under the contractility curve of contractions (P <.05). CONCLUSIONS Our results showed that combined use of low dose trospium and melatonin had strong in vitro inhibitory capability on agonist-induced contractions of rat bladder strips. The present findings may offer an insight into lowering the dose of an antimuscarinic by combining it with an antioxidant and endogenous hormone, melatonin.


Redox Report | 2017

Serum adenosine deaminase, catalase, and carbonic anhydrase activities in patients with renal cell carcinoma

Necip Pirinççi; Tacettin Yekta Kaya; Mehmet Kaba; Tunç Ozan; Ilhan Gecit; Hüseyin Özveren; Hüseyin Eren; Kadir Ceylan

Objectives: To determine whether serum levels of adenosine deaminase (AD), catalase (CAT), and carbonic anhydrase (CA) enzymes may be useful biomarkers in the diagnosis of renal tumors and may lead to early diagnosis of renal tumors. Material and methods: The study included 33 patients with renal cell carcinoma (RCC) and 31 healthy controls. The activity of serum AD, CA, and CAT was determined and analyzed using the Giusti spectrophotometric method, H2O2 substrate, and C02 hydration, respectively. Results: Serum AD and CA activity were significantly higher in patients with RCC than in controls. However, serum CAT activity was significantly lower in patients with RCC than in controls. Conclusion: These markers might be potentially important as an additional biochemical tool for diagnosing RCC. We believe multidisciplinary studies are needed to plan patients’ preoperative and postoperative treatment and to create follow-up protocols.


Turkish Journal of Medical Sciences | 2018

The role of apoptosis and the effect of epidermal growth factor on proapoptotic BNIP 3 in an experimental rat priapism model

Osman Barut; Ahmet Karakeçi; Tunç Ozan; Fatih Firdolaş; Necip Pirincci; Irfan Orhan

Background/aim: This study aimed to investigate the effects of apoptosis-inducing Bcl-2/adenovirus E1B 19 kDa-interacting protein 3 (BNIP 3) and antiapoptotic epidermal growth factor (EGF) on the pathophysiology of experimental low-flow priapism. Materials and methods: Twenty-four adult Sprague-Dawley rats were divided into four equal groups. Group I was the control group. Ischemic priapism was induced for 4 h in Group II rats. In Group III, intraperitoneal EGF at 10 µg/kg was given for 7 days before induction of ischemic priapism for 4 h. In Group IV, intraperitoneal EGF at 20 µg/kg was given for 7 days before induction of ischemic priapism for 4 h. The western blot method was used to determine BNIP 3 expression levels and the TUNEL method was used to determine the apoptotic cells in the cavernosal tissue samples. Results: Although BNIP 3 expression levels were significantly higher in all three study groups compared to the controls, BNIP 3 was significantly higher in EGF-administered groups when compared to Group II (P < 0.05). The TUNEL score of group II was significantly higher than those of the other groups. Conclusion: Decreased apoptosis in cavernosal tissues obtained by antagonizing the apoptotic effect of BNIP 3 with EGF may facilitate the development of new conservative treatment methods via those pathways.


Medical Principles and Practice | 2018

Evaluation of Prolidase Activity, Oxidative Stress, and Antioxidant Enzyme Levels in Testicular and Penile Tissues after Human Chorionic Gonadotropin Treatment in Rats by Predicting Infertility and Erectile Dysfunction

Necip Pirincci; Serkan Yildirim; Abuzer Taş; Yağmur Kuşcu; Tunç Ozan; Fatih Firdolas; Halit Demir; Ahmet Karakeçi

Objectives: Prolidase plays a vital role in collagen turnover, matrix remodeling, and cell growth. We aimed to evaluate the association between treatment with chorionic gonadotropin and infertility and erectile dysfunction by investigating tissue prolidase activity, oxidative stress, and levels of antioxidant enzymes. Materials and Methods: The 16 male Wistar albino rats used in this study were randomly divided into 2 groups: rats treated with human chorionic gonadotropin (hCG) and control rats (n = 8 in each group). The rats in the hCG group were subcutaneously injected with 50 IU hCG daily for 15 days, while the rats in the control group were subcutaneously injected isotonic saline. All of the rats were sacrificed by a lethal overdose of sodium pentobarbital at the first month after hCG administration. Prolidase activity and levels of malonyl aldehyde, glutathione reductase, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) were estimated in the testicular and penile tissue. The testicles and penis were transversely dissected and placed in formalin. Results: Levels of prolidase and malonyl aldehyde in the testicular and penile tissues were significantly higher in the hCG group than in the control group (p < 0.001), while levels of glutathione reductase, SOD, GSH-Px, and CAT were significantly lower in the hCG group than in the control group (p < 0.001). Conclusions: In this study, we observed that treatment with hCG increased prolidase activity and oxidative stress and decreased the antioxidant capacity of penile and testicular tissues; therefore, this may affect fertility and erectile function.


Türk Üroloji Dergisi/Turkish Journal of Urology | 2015

Metabolic syndrome does not impair the response to alfuzosin treatment in men with lower urinary tract symptoms: a double-blind, randomized, placebo-controlled study.

Selçuk Altın; Tunç Ozan; Selçuk İlhan; Nevin Ilhan; Rahmi Onur

OBJECTIVE This study is a placebo-controlled comparison of the response to alfuzosin treatment for lower urinary tract symptoms (LUTS) in patients with and without metabolic syndrome (MetS). MATERIAL AND METHODS A total of 80 men with LUTS were included in the study. Patients had a maximum flow rate of <15 mL/sec, prostate volume of >20 mL, and International Prostate Symptom Score (IPSS) of >8. All eligible men (n=68) for evaluation were initially divided into two groups as MetS (n=34) and non-MetS (n=34) groups. Patients were further randomized to receive alfuzosin (10 mg/day) or placebo (n=17/group; a total of four groups). The outcome was measured at 12(th) week according to the changes from baseline in IPSS, quality of life (QoL) scores, maximum flow rate (Qmax), and postmictional residue. RESULTS Alfuzosin significantly improved LUTS in men with and without MetS compared with patients receiving placebo (p<0.05). Mean IPSS scores in treatment groups decreased significantly, whereas patients receiving placebo had no statistically significant difference (p>0.05). Similarly, alfuzosin treatment resulted in a significant increase in Qmax in patients with LUTS/benign prostatic enlargement when compared with patients in placebo group (p<0.05). Mean QoL scores measured by IPSS-QoL and QoL questionnaires also improved significantly in patients receiving alfuzosin for 3 months regardless of the presence of MetS (p<0.05). CONCLUSION Our results revealed that the presence of MetS in patients with LUTS did not impair the response to alfuzosin treatment.


Diagnosis | 2015

Classical vs. unit area method in the evaluation of differential renal function in unilateral hydronephrosis

Ferat Kepenek; Zehra Pınar Koç; Irfan Orhan; Tansel Ansal Balci; Funda Aydin; Ahmet Fırat Güngör; Tunç Ozan; Cihat Tektaş

Abstract Background: There are some problematic results in determination of differential renal function (DRF) by means of Tc-99m DMSA renal scintigraphy in hydronephrotic kidneys. In this study the classical method (CM) and unit area methods (UAM) in the estimation of DRF in unilateral hydronephrosis before and after intervention were compared. Methods: Twenty patients (12 M, 8 F; mean: 42.6±18.5 years old) who were candidates for surgery or intervention because of unilateral hydronephrosis were the subjects of this study. All the patients were evaluated by Tc-99m DMSA scintigraphy before and 3–6 months after the intervention. In order to estimate DRF both CM and UAM (obtained by division of the counts including the kidney ROI to pixel of the same ROI) were performed. Bland-Altman analyses were performed in order to compare the DRF values obtained from both methods. Results: The agreement between CM and UAM was poor in the preoperative estimation, however, the agreement was good after the operation or intervention. Conclusions: In this study it seems that DRF estimation with CM in unilateral hydronephrosis might be problematic in the determination of surgery thus UAM might be introduced as the method of choice in the determination of DRF in unilateral hyronephrosis.

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Necip Pirincci

Yüzüncü Yıl University

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Halit Demir

Yüzüncü Yıl University

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