Comparative analysis of the results of standard and minipercutaneous nephrolithotripsy for staghorn stones

Introduction. There are conflicting data in the literature on the results of mini-percutaneous nephrolithotripsy (PCNL) in staghorn stones.Objective. To compare the results of standard and mini-PCNL.Materials and methods. The results of PCNL in 90 patients with staghorn stones were analyzed, which were divided into two groups. In the I group, 58 (64.4%) patients underwent standard PNL with a nephroscope 24 Fr, in the II group, 32 (35.6%) patients underwent mini-PCNL with an endoscope 15 Fr. The operative time and the number of postoperative complications were compared. To assess the effectiveness of PCNL, an overview radiography or native computed tomography was performed. The operation was considered successful with residual fragments less than 3 mm.Results. Operative time, number of complications and blood transfusions, the effectiveness of PCNL in groups I and II were 80.0 ± 20.6 and 96.5 ± 25.0 min, 24.1% and 15.6%, 10.3% and 3.1%, 86.2% and 84.4%. Additional interventions were resorted to in 7 (12.1%) patients in I group, and in 4 (12.5%) patients in II group. Complications in I and II groups were observed in 14 (24.1%) and 5 (15.6%) cases. The frequency of blood transfusions was significantly higher after standard PCNL (10.3% / 3.1%, p < 0.05). Complications of grade III with mini-PCNL, replacement of an incorrectly installed stent was included in 2 patients, and with standard PCNL, ureteral stenting with urine leakage through the nephrostomic tract in 2 patients, drainage of the pleural cavity in one case.Conclusion. Standard PCNL is an effective method in staghorn stones, but the number of complications after it remains higher. In selected patients with staghorn stones, the results of mini-PCNL are comparable to those of standard PCNL

Massless BTZ black holes in minisuperspace

We study aspects of the propagation of strings on BTZ black holes. After performing a careful analysis of the global spacetime structure of generic BTZ black holes, and its relation to the geometry of the SL(2,R) group manifold, we focus on the simplest case of the massless BTZ black hole. We study the SL(2,R) Wess-Zumino-Witten model in the worldsheet minisuperspace limit, taking into account special features associated to the Lorentzian signature of spacetime. We analyse the two- and three-point functions in the pointparticle limit. To lay bare the underlying group structure of the correlation functions, we derive new results on Clebsch-Gordan coefficients for SL(2,R) in a parabolic basis. We comment on the application of our results to string theory in singular time-dependent orbifolds, and to a Lorentzian version of the AdS/CFT correspondence.Comment: 28 pages, v2: reference adde

Плотность простатического специфического антигена как прогностический фактор безрецидивной выживаемости у больных локализованным раком предстательной железы, перенесших комбинированное гормонолучевое лечение

Background. Prostate cancer is amongst one of the most prevalent cancers in men worldwide. Combined hormonal-radiation therapy has become a standard of care for localized prostate cancer definitive treatment. As many as 30 % of men are at risk for disease progression within 10 years following radical treatment.Aim. To assess the significance of prostate-specific antigen (PSA) density as a predictor of recurrence-free survival following combined hormonal-radiation therapy in patients with localized prostate cancer.Materials and methods. We conducted a retrospective study of 272 patients with clinically localized prostate cancer treatment results who received combined hormonal-radiation therapy between January 1996 and December 2016.Results. On the basis of our study, we confirmed high prognostic value of PSA density among patients with localized prostate cancer who received combined hormonal-radiation treatment. We utilized ROC-analysis in order to determine the threshold value of the PSA density index – 0.376 ng/ml/cm3, exceeding of which was associated with statistically significant reduction in the recurrence-free survival rate. The area under the curve was 0.711 (95 % confidence interval 0.653–0.764; p <0.0001). The risk of recurrence increased with rising of PSA density.Conclusion. PSA density has proven to be a reliable tool for assessing the risk of prostate cancer recurrence among patients with localized prostate cancer who have undergone combined hormonal-radiation therapy.Введение. Рак предстательной железы является одним из наиболее распространенных онкологических заболеваний. Комбинированная гормонолучевая терапия относится к основным методам радикального лечения рака предстательной железы. У 30 % мужчин возникает прогрессирование заболевания в течение 10 лет после радикального лечения.Цель исследования – определение значимости плотности простатического специфического антигена (ПСА) в качестве предиктора безрецидивной выживаемости после перенесенного комбинированного гормонолучевого лечения у больных локализованным раком предстательной железы.Материалы и методы. В целях оценки клинической и прогностической значимости параметра плотности ПСА проведено ретроспективное исследование результатов лечения 272 пациентов, перенесших комбинированную гормонолучевую терапию в период с января 1996 г. по декабрь 2016 г.Результаты. Установлено прогностическое значение плотности ПСА у больных локализованным раком предстательной железы, получивших комбинированное гормонолучевое лечение. С помощью ROC-анализа определено пороговое значение показателя плотности ПСА – 0,376 нг/мл/см3, превышение которого связано со статистически значимым снижением уровня безрецидивной выживаемости. Площадь под ROC-кривой (AUC) составила 0,711 (95 % доверительный интервал 0,653–0,764; p <0,0001). Риск возникновения рецидива возрастал по мере увеличения показателя плотности ПСА.Заключение. Плотность ПСА, обладая высокими показателями клинической и прогностической значимости, представляет собой надежный инструмент оценки риска возникновения рецидива рака предстательной железы у пациентов, перенесших комбинированное гормонолучевое лечение