Abdullah Armagan

Comparative analysis of the protective effects of melatonin and caffeic acid phenethyl ester (CAPE) on mobile phone-induced renal impairment in rat.

Melatonin and caffeic acid phenethyl ester (CAPE), a component of honeybee propolis, were recently found to be potent free radical scavengers and antioxidants. There are a number of reports on the effects induced by electromagnetic radiation (EMR) in various cellular systems. Mechanisms of adverse effects of EMR indicate that reactive oxygen species may play a role in the biological effects of this radiation. The present study was carried out to compare the protective effects of melatonin and CAPE against 900 MHz EMR emitted mobile phone-induced renal tubular injury. Melatonin was administered whereas CAPE was given for 10 days before the exposure. Urinary N-acetyl-β-D-glucosaminidase (NAG, a marker of renal tubular injury) and malondialdehyde (MDA, an index of lipid peroxidation), were used as markers of oxidative stress-induced renal impairment in rats exposed to EMR. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in renal tissue. Urinary NAG and renal MDA were increased in EMR exposed rats while both melatonin and CAPE caused a significant reduction in the levels of these parameters. Likewise, renal SOD and GSH-Px activities were decreased in EMR exposed animals while melatonin caused a significant increase in the activities of these antioxidant enzymes but CAPE did not. Melatonin caused a significant decrease in urinary NAG activity and MDA levels which were increased because of EMR exposure. CAPE also reduced elevated MDA levels in EMR exposed renal tissue, but the effect of melatonin was more potent than that of CAPE. Furthermore, treatment of EMR exposed rats with melatonin increased activities of SOD and GSH-Px to higher levels than those of control rats. In conclusion, melatonin and CAPE prevent renal tubular injury by reducing oxidative stress and protect the kidney from oxidative damage induced by 900 MHz mobile phone. Nevertheless, melatonin seems to be a more potent antioxidant compared with CAPE in kidney. (Mol Cell Biochem 276: 31–37, 2005)

Comparison of Retrograde Intrarenal Surgery and Mini-percutaneous Nephrolithotomy in Children With Moderate-size Kidney Stones: Results of Multi-institutional Analysis

OBJECTIVE To compare the outcomes of miniaturized percutaneous nephrolithotomy (mini-perc) and retrograde intrarenal surgery (RIRS) in children for 10- to 30-mm renal calculi by evaluating operative data, stone-free rates, and associated complications. METHODS The records of 201 pediatric patients who underwent mini-perc (n = 106) or RIRS (n = 95) for intrarenal stones of 10- to 30-mm size were reviewed retrospectively. The χ(2) test was applied to compare the success rates, postoperative complications, and blood transfusion rates, and the Mann-Whitney U test was used to compare the means of hospital stay, fluoroscopy, and operative time for mini-perc and RIRS. RESULTS The stone-free rate was 84.2% for the RIRS group and 85.8% for the mini-perc group after a single procedure (P = .745). These percentages increased to 92.6% and 94.3% with adjunctive therapies for RIRS and mini-perc, respectively. Minor complications classified as Clavien I or II occurred in 17% and 8.4% in mini-perc and RIRS, respectively. No major complications (Clavien III-V) occurred in either group. Overall complication rates in mini-perc were higher, but the differences were not statistically significant (P = .07). However, 7 patients in the mini-perc group received blood transfusions, whereas none of the children in the RIRS group were transfused (P = .015). The mean hospital stay, fluoroscopy, and operation times were significantly longer in the mini-perc group. CONCLUSION This study demonstrates that RIRS is an effective alternative to mini-perc in pediatric patients with intermediate-sized renal stones. Operative time, radiation exposure, hospital stay, and morbidities of percutaneous nephrolithotomy (PNL) can be significantly reduced with the RIRS technique.

Dietary vitamin C and E modulates oxidative stress induced-kidney and lens injury in diabetic aged male rats through modulating glucose homeostasis and antioxidant systems.

Diabetes induces oxidative stress in aged human and rat, although daily supplementation of vitamins C and E (VCE) can be beneficial to aged diabetic rats by reducing free radical production. The aim of the present study was to evaluate whether dietary VCE supplementation relieves oxidative stress in streptozotocin (STZ)‐induced diabetic in aged rats. Thirty aged rats were randomly divided into three groups. The first group was used as a control. The second group was made diabetic using a single dose of intraperitoneal STZ. VCE‐supplemented feed was given to aged diabetic rats constituting the third group. On the 21st day of the experiment, blood, lens and kidney samples were taken from all animals. Glutathione peroxidase (GSH‐Px) activity in lens and kidney, reduced glutathione (GSH), vitamin E and β‐carotene concentrations in kidney were lower in the diabetic group than in the control whereas plasma glucose, urea and creatinine, and kidney and lens peroxidation (LP) levels were higher in the diabetic group than in the control. However, kidney and lens LP levels, and plasma glucose, urea and creatinine values were decreased by VCE supplementation. Lens and kidney GSH‐Px activity, kidney GSH, vitamin E and β‐carotene concentrations and erythrocyte counts were increased by VCE treatment. Kidney weights, vitamin A, haemoglobin, hematocrit, leukocyte and platelets values were not changed by diabetes and/or VCE supplementation. VCE ameliorated also diabetes‐induced histopathological changes in kidney. In conclusion, we observed that VCE supplementation is beneficial towards kidney and lens of aged diabetic rats by modulating oxidative and antioxidant systems. Copyright

Sildenafil citrate as a phosphodiesterase inhibitor has an antioxidant effect in the blood of men

Background and objective:  Sildenafil citrate enhances the action of nitric oxide by preventing the hydrolysis of cGMP, and is widely used to treat erectile dysfunction. We investigated the effects of sildenafil citrate administration on lipid peroxidation and antioxidant redox enzymes in blood of healthy men.

Caffeic acid phenethyl ester modulates methotrexate-induced oxidative stress in testes of rat.

The aim of this study was to investigate the possible protective role of caffeic acid phenethyl ester on testicular toxicity of methotrexate in rats. Nineteen male rats were divided into three groups as follows: group I, control; group II, methotrexate-treated; group III, methotrexate + caffeic acid phenethyl ester-treated. In the second day of experiment, a single dose of methotrexate was intraperitoneally administered to groups II and III, although a daily single dose of caffeic acid phenethyl ester was intraperitoneally administered to group III for 7 days. At the end of the experiment, the testes of the animals were removed and weighed. In the tissue, the level of lipid peroxidation as malondialdehyde and activities of superoxide dismutase were higher in the methotrexate group than in the control group. Lipid peroxidation levels and superoxide dismutase activities were decreased in caffeic acid phenethyl ester + methotrexate group compared with methotrexate group. The activities of catalase in the methotrexate group decreased insignificantly although its activities were significantly increased by caffeic acid phenethyl ester administration. The activity of glutathione peroxidase did not change in the groups. There was significant difference in body weight between control and methotrexate-induced groups. In conclusion, the administration of methotrexate causes elevation of oxidative stress although treatment with caffeic acid phenethyl ester has protective effects on the oxidative stress in testes.

Topiramate and vitamin e modulate antioxidant enzyme activities, nitric oxide and lipid peroxidation levels in pentylenetetrazol-induced nephrotoxicity in rats.

Previous studies have shown that generation of free radicals is increased following pentylenetetrazol kindling, due to increased cytosolic Ca2+ concentrations. Topiramate, a voltage-gated calcium channel inhibitor, has an evident effect in the treatment of childhood epilepsy; however, topiramate may cause nephrotoxicity. We investigated the effects of topiramate and vitamin E administration on pentylenetetrazol-induced nephrotoxicity in rats by evaluation of lipid peroxidation, nitric oxide, glutathione peroxidase, catalase and superoxide dismutase values. Forty male Wistar rats were randomly divided into five equal groups. Group 1 was used as control and group II received a single dose of pentylenetetrazol. Fifty and 100 mg/kg topiramate daily were intragastrically administered to rats in groups III and IV for 7 days, respectively. Intragastric 100 mg topiramate (daily for 7 days) and intraperitoneal vitamin E (150 mg/kg, daily for 3 days) combination were given to animals in group V before a single-dose pentylenetetrazol administration. Serum and kidney samples were taken after 3 hr of pentylenetetrazol administration. Pentylenetetrazol resulted in a significant increase in nitric oxide levels of serum and kidney, and lipid peroxidation levels of kidney although superoxide dismutase and catalase activities in the kidney was reduced by pentylenetetrazol administration. The lipid peroxidation levels in serum and kidneys and the nitric oxide levels in kidneys of groups III, IV and V were decreased by topiramate although the superoxide dismutase and catalase activities in the kidneys were increased. Lipid peroxidation and nitric oxide levels were reduced by the topiramate and vitamin E combination compared to only topiramate. Glutathione peroxidase activity was not affect by pentylenetetrazol, topiramate and vitamin E administrations. In conclusion, topiramate and vitamin E have protective effects on pentylenetetrazol-induced nephrotoxicity by inhibition of free radicals and by support of the antioxidant redox system.

Ileal orthotopic neobladder (modified Hautmann) via a shorter detubularized ileal segment: experience and results.

To evaluate the clinical, urodynamic, functional, radiological and metabolic results of the ileal (modified Hautmann) orthotopic neobladder over 10 years of experience.

Comparison of Shockwave Lithotripsy and Microperc for Treatment of Kidney Stones in Children

PURPOSE We aimed to compare the outcomes of microperc and shockwave lithotripsy (SWL) for treatment of kidney stones in children. PATIENTS AND METHODS The medical records of 145 patients under the age of 15 years with opaque and single kidney stones treated with either SWL or microperc were retrospectively reviewed. Both groups were compared in terms of fluoroscopy and operative time, re-treatment, complications, success rate, and secondary and total number of procedures. RESULTS Microperc and SWL were performed on 37 and 108 pediatric patients, respectively. The mean age of the patients was 5.91±4.03 years (1-15) and 8.43±4.84 (1-15) years in the SWL and microperc groups, respectively (P=0.004). The mean stone size was 11.32±2.84 (5-20) mm in the SWL group and 14.78±5.39 (6-32) mm in the microperc group (P<0.001). In the SWL group, 31 (28.7%) patients underwent a second SWL session and 6 (5%) had a third session. Finally, 95 (88%) patients were stone free at the end of the SWL sessions. In the microperc group, the stone-free rate was 89.2% in a single session (P=0.645). The mean duration of hospitalization was 49.2±12.3 (16-64) hours in the microperc group and 8.4±2.3 (6-10) hours per one session in the SWL group (P<0.001). The fluoroscopy time was significantly longer in the microperc group compared with the SWL group (147.3±95.3 seconds vs 59.6±25.9 seconds, P<0.001). The rate of requirement for an auxiliary procedure was higher in the SWL group than in the microperc group. The overall complication rates for the microperc and SWL groups were 21.6% and 16.7%, respectively (P=0.498). CONCLUSIONS The results of our study demonstrate that microperc provides a similar stone-free rate and a lower additional treatment rate compared with SWL in the treatment of kidney stone disease in children.

Risk Factors for the Formation of a Steinstrasse after Shock Wave Lithotripsy

Introduction: We studied the various stone, renal, and therapy factors that could affect steinstrasse formation after shock wave lithotripsy (SWL) to define their predictive value. Patients and Methods: Between May 1999 and September 2002, 563 patients were treated with a Stonelight V3 lithotriptor. A steinstrasse was recorded in 46 patients. All patient data, stone and renal characteristics, and data of SWL were reviewed. Statistical analyses of patients, stones, and therapy characteristics in correlation with the incidence of steinstrasse formation were performed to assign factors that had a significant impact on the formation of this complication. Results: The overall incidence of a steinstrasse was 8.17%. The steinstrasse was in the pelvic ureter in 84.3% of the cases, in the iliac ureter in 7.84% of them, and in pelvic and iliac ureter in 7.84% of the patients. The incidence of a steinstrasse significantly correlated with stone size and site. The incidence rates of a steinstrasse in renal stones <1 cm, 1–2 cm, and >2 cm were 4.46, 15.87, and 24.3% respectively. The incidence rates of this complication in ureteral stones <1 cm and 1–2 cm were 3.37 and 9.52%, respectively. The incidence rates of a steinstrasse in stones located in upper calices, middle calices, lower calices, and renal pelvis were 6.12, 10.52, 6.36, and 19.32%, respectively. Conclusions: Stone size and site are the significant factors predicting the formation of a steinstrasse. If a patient has a high probability of steinstrasse formation, close follow-up with early intervention or prophylactic pre-SWL ureteral stenting is indicated.

Effects of tamoxifen on vaginal blood flow and epithelial morphology in the rat

BackgroundTamoxifen, a selective estrogen receptor modulator with both estrogenic and anti-estrogenic activity, is widely used as adjuvant therapy in breast cancer patients. Treatment with tamoxifen is associated with sexual side effects, such as increased vaginal dryness and pain/discomfort during sexual activity. There have been limited investigations of the effect of tamoxifen on estrogen-dependent peripheral genital arousal responses. The objective of this study was to investigate the effects of tamoxifen on vaginal physiology in the rat.MethodsFemale Sprague-Dawley rats were subjected to sham surgery or bilateral ovariectomy. After 2 weeks, sham-operated rats were implanted with subcutaneous osmotic infusion pumps containing vehicle (control) or tamoxifen (150 μg/day). Ovariectomized rats were similarly infused with vehicle. After an additional 2 weeks, vaginal blood flow responses to pelvic nerve stimulation were measured by laser Doppler flowmetry and vaginal tissue was collected for histological and biochemical assay.ResultsTamoxifen treatment did not change plasma estradiol concentrations relative to control animals, while ovariectomized rats exhibited a 60% decrease in plasma estradiol. Tamoxifen treatment caused a significant decrease in mean uterine weight, but did not alter mean vaginal weight. Vaginal blood flow was significantly decreased in tamoxifen-infused rats compared to controls. Similar to ovariectomized animals, estrogen receptor binding was increased and arginase enzyme activity was decreased in tamoxifen-infused rats. However, different from control and ovariectomized animals, the vaginal epithelium in tamoxifen-infused rats appeared highly mucified. Periodic acid-Schiff staining confirmed a greater production of carbohydrate-rich compounds (e.g. mucin, glycogen) by the vaginal epithelium of tamoxifen-infused rats.ConclusionThe observations suggest that tamoxifen exerts both anti-estrogenic and pro-estrogenic effects in the vagina. These physiological alterations may eventually lead to vaginal atrophy and compromise sexual function.