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Öğe Do renal cysts affect the success of extracorporeal shockwave lithotripsy? A retrospective comparative study(2013) Gücük, Adnan; Öztürk, Ufuk; Üyetürk, Uğur; Kemahlı, Eray; Akın, Güven; İmamoğlu, M.Abdurrahim; Metin, AhmetThe aim of this study was to assess the effect of simple renal cysts on extracorporeal shockwave lithotripsy (SWL) in patients with calyceal renal calculi. Patients with simple renal cysts >35 mm and ipsilateral renal calculi <20 mm that were treated with SWL constituted group 1 (cyst + calculi). The control group included patients aged >40 years that had renal calculi <20 mm and no cysts that were treated with SWL. The 2 groups were compared according to age, gender, body mass index, calculi size, localization, and density, the calculi fragmentation rate, and the percentage of stone-free patients. Mean cyst size in group 1 was 44.04 ± 9.08 mm. Mean age in group 1 was 61.4 ± 10.2 years versus 56.9 ± 8.2 years in the control group; the difference was significant (P = 0.045). There were not any other significant differences between the 2 groups, except for the stone-free rate (P > 0.05), which was 33.3% in group 1 and 68.2% in the control group (P = 0.017). The presence of renal cysts in a patient with calculi requires that an individualized treatment plan be devised, so as to provide the patient with the most effective treatment. © 2013 Adnan Gücük et al.Öğe Does the hounsfield ünit value determined by computed tomography predict the outcome of percutaneous nephrolithotomy?(Mary Ann Liebert Inc, 2012) Gücük, Adnan; Üyetürk, Uğur; Öztürk, Ufuk; Kemahlı, Eray; Yıldız, Mevlüt; Metin, AhmetPurpose: We aimed to evaluate whether the Hounsfield unit (HU) value predicts outcome in percutaneous nephrolithotomy (PCNL). Patients and Methods: One hundred and seventy-nine patients who had undergone PCNL in our clinics in the last 4 years were included. Demographic and clinical data of the patients and complications, if any, were recorded. The mean age of the patients was 45.3 +/- 14.3 years (range 5-82 y), and 111 of them were males (62%). The mean stone size and HU values were found to be 693.1 +/- 628.0 (95-4200) mm 2 and 706.3 +/- 245.0 (214-1325), respectively. Results: In logistic regression analysis, the size of the stone, the opacity of the stone, and the HU values were found to be independent predictors of the failure of the procedure (P < 0.05). A cutoff value of 677.5 was used for the HU in the receiver operating characteristics analysis. Having a HU value under the cutoff value increased the likelihood of procedure failure by 2.65 times, whereas stones residing in the staghorn localization increased failure by 5.68. It was also observed that if the stone's size was 485 mm(2) or more, the chance of failure increased by 1.9, whereas when the stone was nonopaque, failure increased by 6.04 times (P < 0.05). There was a positive correlation between hematocrit decrease and a decrease in HU values (P < 0.05), but no correlation was observed between the HU values and duration of surgery or fluoroscopy (P > 0.05). Conclusion: In addition to the size and location of the stones, the HU value determined in the unenhanced CT scan may be one of the parameters affecting PCNL outcomes. PCNL is a more efficient method in stones with higher HU values. Therefore, the HU values may be a useful tool for the selection of the treatment modality in patients with renal stones.Öğe Effects of sildenafil treatment on patients with Peyronie's disease and erectile dysfunction(Springer London Ltd, 2014) Öztürk, Ufuk; Yeşil, Süleyman; Göktuğ, Hasan Nedim Göksel; Gücük, Adnan; Tuygun, CanIt has been shown on experimental rat models that type 5-phosphodiesterase isoenzyme (PDE5) inhibitors have anti-fibrotic effects for Peyronie's disease (PD); however, this issue has not been addressed clinically. The aim of this study was to document the effects of PDE5 inhibitors used for erectile dysfunction (ED) seen in PD patients on the main course of the PD clinically. A total of 39 PD patients with ED were divided into two groups. Patients in Group 1 (n = 18) served as controls and received 400 IU vitamin E per day. Those in Group 2 (n = 21) received 50 mg sildenafil per day for 12 weeks. Penile plaque volume was assessed by palpation and by duplex ultrasound. Erectile capacity, penile deformity and plaque characteristics were assessed by the International Index of Erectile Function questionnaire form (IIEF-5) and penile duplex ultrasound. Statistically significant improvement in all parameters was observed within both groups except for IIEF score in Group 1 when compared with the initial values. Significant reduction in plaques and pain were observed in 7 (33.3 %) and 14 (66.6 %) patients in Group 2 and 6 (33.3 %) and 9 patients (42.8 %) in Group 1, respectively. At the end of the therapy, improvement in IIEF score and reduction in pain were statistically significant in Group 2 compared with Group 1 (p = 0.028 and p = 0.045, respectively). We conclude that continuous administration of oral PDE5 inhibitors may be a candidate for medical treatment of PD; however, more controlled studies are needed.Öğe EXPLORING NEW DIRECTIONAL CURVES OF A SPACELIKE CURVE IN MINKOWSKI 3?SPACE(Asia Pacific Academic, 2024) Al-Obaidi, Shaymaa S. A.; Mahmood, Ghassan A. Mahmood; Öztürk, UfukIn this study, we explore new associated curves in Minkowski 3?space E31 by using the Darboux frame {T, ?, ?} instead of Frenet frame {T, N, B} of the spacelike curve ? having a spacelike principal normal lying on a timelike surface M. These associated curves, denoted as¯Dn,¯Dr, and¯Do, lie in planes defined by {?, ?}, {T, ?}, and {T, ?}, respectively. We establish relationships between the Darboux frame and the curvatures kg, kn, ?g of the curve ? as well as the Frenet apparatus of the associated curves. Furthermore, we derive necessary and sufficient conditions for these associated curves to exhibit helical or spherical characteristics. Finally, we present relevant examples. © 2024 Asia Pacific Journal of Mathematics.Öğe Numerical computing of isophote curves, general helices, and relatively normal-slant helices in Minkowski 3-space(Wiley, 2022) Öztürk, Ufuk; Nesovic, Emilija; Öztürk, Esra Betül KoçIn this paper, we present a method for numerical computing of some characteristic kinds of non-null curves lying on a non-degenerate surface in Minkowski space 13. Namely, we obtain the system of the first-order ordinary differential equations that correspond to general helix, relatively normal-slant helix, and isophote curve and integrate it under chosen initial conditions by applying the ode45 function of MATLAB and Runge-Kutta method. Depending on the kind of curve, we assume that parametric equation of the surface, an axis vector, value of the real cosine or hyperbolic cosine of the corresponding pseudo angle between axis vector and Darboux frame's vector, normal curvature, and geodesic torsion of the curve are given. Finally, we provide the related examples of numerically computed characteristic curves.Öğe On generalized Darboux frame of a spacelike curve lying on a lightlike surface in Minkowski space E31 Dedicated to the memory of Professor Emeritus Krishan Lal Duggal(Scientific and Technological Research Council Turkey, 2023) Djordjevic, Jelena; Nesovic, Emilija; Öztürk, UfukIn this paper we introduce generalized Darboux frame of a spacelike curve alpha lying on a lightlike surface in Minkowski space E31 . We prove that alpha has two such frames and obtain generalized Darboux frame's equations. We find the relations between the curvature functions kg, kn , tau g of alpha with respect to its Darboux frame and the curvature functions k similar to g, k similar to n , tau similar to g with respect to generalized Darboux frames. We show that such frames exist along a spacelike straight line lying on a ruled surface which is not entirely lightlike, but contains some lightlike points. We define lightlike ruled surfaces on which the tangent and the binormal indicatrix of a null Cartan curve are the principal curvature lines having tau similar to g = 0 and give some examples.Öğe On non-null relatively normal-slant helices in minkowski 3-space(Univ Nis, Fac Sci Math, 2022) Nesovic, Emilija; Öztürk, Ufuk; Öztürk, Esra Betül KoçBy using the Darboux frame {;xi, zeta, eta} of a non-null curve lying on a timelike surface in Minkowski 3-space, where xi is the unit tangent vector of the curve, eta is the unit spacelike normal vector field restricted to the curve and zeta = +/-eta x xi, we define relatively normal-slant helices as the curves satisfying the condition that the scalar product of the fixed vector spanning their axis and the non-constant vector field zeta is constant. We give the necessary and sufficient conditions for non-null curves lying on a timelike surface to be relatively normal-slant helices. We consider the special cases when non-null relatively-normal slant helices are geodesic curves, asymptotic curves, or lines of the principal curvature. We show that an asymptotic spacelike hyperbolic helix lying on the principal normal surface over the helix and a geodesic spacelike general helix lying on the timelike cylindrical ruled surface, are some examples of non-null relatively normal-slant helices in E-1(3)Öğe Posttraumatic high-flow nonischemic priapism(Lippincott Williams & Wilkins, 2018) Nalbant, İsmail; Tuygun, Can; Gücük, Adnan; Conkbayır, Işık; Öztürk, Ufuk; Yılmaz, Muhammed Şahin; İmamoglu, Muhammed AbdurrahimPriapism is an uncommon disorder, and nonischemic priapism is seen less frequently in children, generally after trauma. Although it seems to be an advantage that urgent intervention is not required because of no cavernous ischemia, it is likely to be misdiagnosed because of the asymptomatic potential. We aimed to present a case of posttraumatic nonischemic priapism.Öğe Renal apoptosis after shockwave application in rabbit model(Mary Ann Liebert Inc, 2006) Çimentepe, Ersin; Eroğlu, Muzaffer; Öztürk, Ufuk; Bayrak, Ömer; Tuygun, Can; Acar, Abuzer; Üzüm, NüketPurpose: To identify any apoptotic effect of shockwave lithotripsy (SWL) on renal tubular and glomerular cells. Materials and Methods: Thirty-five male New Zealand White rabbits were divided into five groups of seven rabbits each: I (control), II (sham), and III, IV, and GV (treated and sacrificed 1, 7, and 28 days after SWL, respectively). Intramuscular anesthetic agent (ketamine HCl; 20 mg/kg) and intravenous contrast medium (iohexol 300 mg of I/mL) were administered to animals in group II. The left kidneys of animals in groups III, IV, and V were exposed to 2000 shockwaves at 18 kV after administration of anesthesia and contrast medium. The animals were sacrificed on day 1, 7, or 28 after SWL, and the kidneys were removed. Apoptotic and proliferative indices of renal tubular and glomerular cells were determined by terminal deoxynucleotidyl transferase dUTP nick and label (TUNEL) and Ki-67 labeling methods, respectively, counting 1000 cells in each preparation. Results: No apoptosis was detected in glomerular cells in any group. The mean apoptotic indices of the tubular cells in animals in groups I and II were 483.0 +/- 85 and 484.4 +/- 105, respectively with no significant difference between the groups. In groups III and IV, the mean apoptotic indices were 343.4 +/- 89 and 358.4 +/- 61, respectively. There were no statistically significant differences between groups III and IV and the control group. Similarly, there were no significant differences in the apoptotic indices in groups III and IV. However, the apoptotic index in group V was 821.4 +/- 57, significantly higher than in the control group. The proliferative indices of all SWL groups were lower than that of the control group. Conclusion: Shockwave lithotripsy has an apoptotic effect on renal tubular cells that can be detected 4 weeks after the procedures, but no apoptotic effect on glomerular cells. Treatment with SWL also attenuates the proliferation of both tubular and glomerular cells.Öğe Some characterizations of pseudo null isophotic curves in Minkowski 3-space(Springer Basel Ag, 2021) Nesovic, Emilija; Öztürk, Ufuk; Öztürk, Esra Betül KoçIn this paper, we define and characterize pseudo null isophotic curves lying on a non-degenerate surface in Minkowski 3-space. We find the relation between Darboux frame's Darboux vector (angular velocity vector, centrode) (D) over bar of such curves and Frenet frame's Darboux vector D. We prove that D spans their axes if and only if it coincides with (D) over bar. In particular, we show that the only pseudo null isophotic curves whose axes are spanned by D are pseudo null helices. Finally, we provide the related examples.
