Tevfik Ziypak

Antioxidative status and lipid peroxidation in kidney tissue of rats fed with vitamin B(6)-deficient diet.

Introduction: The aim of this study was to evaluate lipid peroxidation (LP) and free radical scavenging enzyme activities in kidney tissue of vitamin B6-deficient rats. Material and Methods: The rats were divided into control and vitamin B6-deficient groups. After 4 weeks of feeding, animals in all groups were anesthetized by thiopental sodium (50 mg/kg). Thoraces were opened, 2 mL blood samples were taken from aortas, then the rats were killed by cervical dislocation, and kidney tissues were removed. Biochemical measurements in kidney tissue were carried out using a spectrophotometer. Results: Total superoxide scavenger activity (TSSA), nonenzymatic superoxide scavenger activity (NSSA), superoxide dismutase (SOD) activities, and antioxidant potential (AOP) values in the vitamin B6-deficient group were significantly lower than those of the control group, whereas glutathione peroxidase (GSH-Px), glutathione reductase (GRD), glutathione-S-transferase (GST) activities, and malondialdehyde (MDA) level were significantly higher than those of the control group (p < 0.05). Discussion: The results show that vitamin B6 deficiency causes an attenuation in antioxidant defense system and an increase in oxidative stress in kidney tissue of rats.

Renoprotective effect of aliskiren on renal ischemia/reperfusion injury in rats: electron microscopy and molecular study

Abstract Purpose: To determine the protective effect of aliskiren on ischemia–reperfusion (I/R) injury in a rat renal (I/R) model. Methods: Rats were randomly divided into five groups: sham control group; sham control with aliskiren pretreatment; I/R group and I/R with two doses of aliskiren pretreatment. Rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 24 h reperfusion. Aliskiren (50 and 100 mg/kg) was administered orally by gavage 24 and 1 h prior to ischemia. After 24 h reperfusion, kidney samples were taken for the determination of malondialdehyde (MDA) level, superoxide dismutase (SOD), glutathione (GSH) activity and histological evaluation. The level of serum creatinine (SCR) and blood urea nitrogen (BUN), renin and angiotensin II (AT-2) was measured in serum samples. Results: Kidneys from I/R groups showed significant increase in MDA level and significant decrease in GSH, and SOD activity. IL-1β, iNOS and NFkB gene expression significantly increased in the I/R groups in the rat kidney tissue. Aliskiren treatment showed a significant down-regulatory effect on IL-1β, iNOS and NFkB mRNA expression. Compared with the sham group, SCR and BUN, renin and AT-2 were significantly increased in the I/R rats, accompanied by histopathological damage to the kidney. Conclusion: Pretreatment with aliskiren ameliorated I/R-induced renal injury through decreasing nitric oxide and AT-2 levels and by the reduction of injury induced by I/R injury and ameliorated renal histopathological molecular and biochemical changes.

Is Urinary Kidney Injury Molecule-1 a Noninvasive Marker for Renal Scarring in Children With Vesicoureteral Reflux?

OBJECTIVE To examine whether (1) levels of urinary kidney injury molecule-1 (KIM-1), a transmembrane protein and biomarker for renal tubular damage, increase in children with of vesicoureteral reflux (VUR), and (2) if KIM-1 predicts the grade of renal scarring in children with VUR. METHODS The study included 59 VUR patients with renal scarring, 5 VUR patients without renal scarring and 25 healthy controls aged 1 to 17 years. Dimercaptosuccinic acid scans were performed for determination of scarring and graded by 3 independent, blinded pediatric urologists for renal scarring according to the Randomized Intervention for Children with VUR study criteria. Spot urine samples were obtained. Urinary KIM-1 and creatinine levels were measured and the KIM-1/creatinine ratio was calculated. RESULTS Urine geometric mean KIM-1 levels (ng/mg creatinine) were significantly higher in VUR patients than in healthy controls (P=.018). Although the correlation between VUR grade and geometric mean KIM-1 levels was not significant, a positive correlation was found for scarring grade and geometric mean KIM-1 levels (r=.30, P=.02). When the patients were divided by subgroups according to scarring grade (group I, grade 1; group II, grades 2 and 3; group III, grade 4), the log KIM-1 in group III was significantly higher than in group I (P=.004). CONCLUSION Urinary KIM-1 levels might be used as a noninvasive marker, particularly in showing severe scarring in children with VUR.

The Forgotten Ureteral Stent in Children: From Diagnosis to Treatment

PURPOSE We conducted a multicenter pediatric study of ureteral stents unintentionally left in situ. MATERIALS AND METHODS A total of 22 patients with encrusted Double-J® ureteral stents unintentionally left in situ were treated at 4 centers between January 2007 and March 2012. Stone burdens were estimated using plain radiography and computerized tomography. Treatment decision was made based on clinical and radiological findings or stone burden. RESULTS Nine girls and 13 boys with a mean age of 9.5 years (range 2 to 16) were analyzed. Mean indwelling time of ureteral stent was 21.7 months (range 6 to 60). Stents were inserted for the indication of urolithiasis (17 patients) and reconstructive urological intervention (5). In 2 patients stents had been placed bilaterally. Mean stent stone burden was 184 mm(2) on plain radiography and 247 mm(2) on computerized tomography, a difference that was statistically significant (p = 0.002). Shock wave lithotripsy was done in 6 cases. Endoscopic procedures were performed in all patients, including ureteroscopy in 8, simple stent removal in 7, endoscopic cystolithotripsy in 6, percutaneous nephrolithotomy in 5, retrograde intrarenal surgery in 3 and percutaneous cystolithotripsy in 2. Surgical removal of each stent required a mean of 1.5 interventions and a mean hospital stay of 4.4 days. CONCLUSIONS At experienced centers combined endourological techniques can achieve successful and safe management of forgotten stents even in the pediatric age group. Thus, routine preprocedural tomography is a must in children with forgotten ureteral stents.

The Effects of RAAS Inhibition in Rate Limiting Step by Aliskiren on Testicular Torsion Injury in Rats

PURPOSE Testicular torsion is a urological emergency. Failure of timely intervention for this issue leads the testicles to go into necrosis. If left untreated, it can lead to loss of the reproductive organs. The aim of this study was to examine the role of aliskiren in testicular torsion and detorsion injuries. MATERIALS AND METHODS Rats were divided into 8 groups of 12 each, including no torsion-detorsion, no torsion-detorsion plus 200 mg/kg aliskiren orally, torsion, torsion-detorsion, torsion plus 100 mg/kg aliskiren orally, torsion plus 200 mg/kg aliskiren orally, torsion-detorsion plus 100 mg/kg aliskiren orally and torsion-detorsion plus 200 mg/kg aliskiren orally. Aliskiren was administered 30 minutes before ischemia and reperfusion, and also 24 hours before the experimental protocol in all treatment groups. Ischemia and reperfusion were each applied for 2 hours. RESULTS Testicular damage decreased superoxide dismutase and glutathione, and increased malondialdehyde in the testis tissues of rats. Aliskiren administration increased superoxide dismutase and glutathione, and decreased malondialdehyde in the testis tissues. Values were measured by a biochemical autoanalyzer. In addition, this torsion-detorsion damage caused a significant increase in levels of the inflammatory cytokine and agents interleukin-1β and inducible nitric oxide synthase, as examined by real-time polymerase chain reaction. Aliskiren administration decreased these parameters. On pathological evaluation administration of a 200 mg/kg dose of aliskiren was found to protect the testis. Renin-angiotensin-aldosterone system inhibition by aliskiren caused an increase in serum renin levels and a decrease in serum angiotensin II levels. CONCLUSIONS It appears that aliskiren protects the testis from ischemia-reperfusion damage by regulating inflammation and the oxidant-antioxidant balance via renin-angiotensin-aldosterone system inhibition.

Flexible ureterorenoscopy for the treatment of kidney stone within pelvic ectopic kidney.

OBJECTIVE To present the outcomes of flexible ureterorenoscopy (F-URS) and laser lithotripsy for the treatment of calculi within pelvic ectopic kidney (PEK). PATIENTS AND METHODS We retrospectively reviewed the medical records of 26 patients with calculi in PEK treated with F-URS in 5 referral hospitals between 2010 and 2013. Patient demographics and stone characteristics (age, sex, body mass index, stone size, location, history of shock wave lithotripsy or kidney surgery), and perioperative measures (duration of operation, fluoroscopic imaging, and hospitalization and success and complication rates) were reviewed. RESULTS A total of 26 patients with mean age of 41.1 ± 15.8 years (7-72 years) were included in the study. The mean stone size was 17.0 ± 5.1 mm (10-28 mm). The mean procedure and fluoroscopy times were calculated as 52.1 ± 27.7 minutes (30-120 minutes) and 54.8 ± 48.9 seconds (10-180 seconds), respectively. The mean length of hospital stay was 2.7 ± 1.8 days (1-9 days). Treatment was deemed successful in 22 patients (84.6%). Ureteroscopy failed in 4 patients (15.4%) due to impaired passage of fragments (n = 3) or inability to reach the stone secondary to the location in an isolated lower calyx (n = 1). Minor postoperative complications were observed in 5 patients (19.2%; persistent hematuria [n = 1], fever [n = 1], renal colic [n = 2], and urinary tract infection [n = 1]). No severe complications or mortality occurred. CONCLUSION Our results suggest that F-URS is a safe and effective minimally invasive treatment modality for small- and medium-sized stones in PEK.

Diagnostic efficiency of multidetector computed tomography with multiplanar reformatted imaging and virtual cystoscopy in the assessment of bladder tumors after transurethral resection.

Purpose: In the assessment of recurrent bladder tumors, diagnostic efficiency of virtual cystoscopy carried out by multidetector computed tomography (MDCT) was investigated and compared with the criterion standard of conventional cystoscopy. Materials and Methods: Twenty-seven patients between 39 and 83 years who had undergone transurethral resection because of bladder tumors were assessed using virtual and conventional cystoscopy. Virtual cystoscopy was performed using a 16-MDCT (Aquilion, Toshiba Medical Systems, Tokyo, Japan) in the supine and prone positions. After axial scanning, the 2-dimensional axial images were assessed, followed by coronal and sagittal multiplanar reconstruction of the images. In addition, virtual cystoscopy and cystographic investigations were performed using software in which volume-rendering technical algorithms shaded the surface display. In the images obtained, the existence and localization of lesions, morphological features, environment invasions, involvement of lymph nodes, and, if any, metastases of abdomen were assessed. Results: For bladder pathologies, the sensitivity and specificity of CT cystography coupled with virtual cystoscopy were 91% and 92%, respectively. The percentage of correct diagnoses using CT cystography was 92%. In addition to bladder pathologies, we investigated liver metastases, kidney cysts, fluid in abdomen, and lymphadenopathies. Conclusions: Using MDCT with virtual cystoscopy to assess primary bladder tumors and, in particular, to determine tumor recurrence after transurethral resection is a minimally invasive method that can be used in the long-term follow-up care of patients.

Antiapoptotic effects of dehydroepiandrosterone on testicular torsion/detorsion in rats

In the present study, we aimed to evaluate the effects of dehydroepiandrosterone (DHEA) on apoptosis of testicular germ cells after repair of testicular torsion in rats. Twenty‐four adult male Sprague‐Dawley rats were randomly divided into four groups, with six rats in each group: sham operation, torsion/detorsion (T/D), T/D + vehicle, and T/D + DHEA. Three hours before detorsion, 50 mg kg−1 DHEA was given intraperitoneally to T/D + DHEA group. In all groups, bilateral orchiectomies were performed and both testicles were histologically examined, with apoptosis detected using the in situ DNA fragmentation [terminal deoxynucleotidyl transferase‐mediated deoxyuridine triphosphate nick‐end labeling (TUNEL)] system, with morphological damage detected using a four‐level grading scale in each specimen. The testes of the sham group showed a normal histology. In T/D and T/D + vehicle groups, apoptotic spermatogonia and spermatocyte number were significantly higher than in the sham group (P < 0.01 for all). The T/D + DHEA group showed a reduction in apoptotic spermatocyte and spermatogonia number in seminiferous epithelia compared with T/D group (P < 0.01 for both). Apoptotic cell number of contralateral testes did not reveal any significant differences among these groups (P > 0.05). Specimens from T/D and T/D + vehicle had a significantly greater histological injury than sham and T/D + DHEA groups in the ipsilateral testes (P < 0.01 for both). Therefore, the results suggest that DHEA may be a protective agent for preventing apoptosis caused by testicular torsion.

Ureteroscopy and holmium laser lithotripsy: Is this procedure safe in pregnant women with ureteral stones at different locations?

OBJECTIVES The aim of this study was to assess the safety and effectiveness of ureteroscopy and Holmium: Yttrium-Aluminum-Garnet lithotripsy for the treatment of ureteral stones with different localizations in symptomatic pregnant women. METHODS A retrospective analysis was performed on 19 pregnant patients referred to our center between January 2005 and December 2012 with symptomatic hydronephrosis requiring surgical intervention. 7.5 F and 9.5 F semirigid ureterorenoscopy with Holmium laser lithotripsy was used for treatment in all patients. Complications were stratified according to modified Clavien criteria. RESULTS The mean age of patients was 25.4 (18-41) years, and the mean gestation duration was 24.8 (7-33) weeks. Six cases (31.5%) had a history of stone. Solitary kidney secondary to previous nephrectomy was observed in 2 patients and 1 patient had a hypoplastic kidney. Abdominal ultrasonography was used as the main diagnostic tool. Mean stone size was 9.2 mm (6-13). The location of the stones was the lower, middle, and upper ureter in 8 (42.1%), 5 (26.3%) and 6 (31.5%) cases, respectively. All stones were fragmented with Holmium laser lithotripsy. Of the 19 patients, 11 (57.8%) required double J stent insertion peroperatively. Intraoperative urological and obstetric complications were not observed. Postoperatively two complications were noted. According to Clavien criteria a complication was level 1, and the other was level 2. CONCLUSIONS For treatment of pregnant women with symptomatic ureteral stones in every location, Holmium laser lithotripsy with a semirigid ureteroscopy can be used as judicious treatment. This approach is effective and safe with an acceptable complication rate.

Rigid Ureteroscope Aided Insertion of Ureteral Access Sheath in Retrograde Intrarenal Surgery

OBJECTIVE To compare the outcomes of the ureteral access sheath (UAS) placement techniques in patients undergoing retrograde intrarenal surgery. MATERIALS AND METHODS The patients were divided into two groups with respect to placement method of UAS. UAS was placed with the classical method, through the guidewire, in the first group of the patients (group I). The outer sheath of UAS was worn on the semirigid endoscope and placed into the ureter under direct vision in the second group (group II). The number of patients was the same in two groups (n = 42). RESULTS Overall, 70 of 84 (83.3%) patients were stone free after the initial treatment. The success rates were comparable between the two groups (80.9% vs 85.7%, P = .859) 1 month after surgery. Fluoroscopy screening time (11.7 ± 5.7 seconds vs 0 second), UAS placement time (245 ± 138.4 seconds vs 40 ± 17.9 seconds; P < .001), and operation time (58.7 ± 17.1 minutes vs 51.2 ± 16.7 minutes; P = .046) were significantly longer in group I when compared to group II. The complication rate was higher in group I when compared to group II (23.8% vs 9.5%), but the difference was not statistically significant (P = .079). CONCLUSION Introducing UAS into ureter under direct vision while it was precisely worn on ureteroscope makes this step safer, and protects the surgeon and patient from radiation exposure by shortening fluoroscopy and operation times.