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OBJECTIVES: Percutaneous Renal Surgery (PRS) is a demanding procedure and success is mostly hampered by the lacking of training facilities. Thus, the purpose of the study was to evaluate a significantly improved pre-existing porcine kidney-training model for percutaneous renal access and PRS. MATERIALS AND METHODS: A biologic training model using porcine kidneys coated by a full-thickness porcine skin flap was prepared. The ureter was dissected, stones were placed into the collecting system using an 18F amplatz sheath, and a catheter was placed in the ureter for further irrigation with saline or contrast medium. For initial training with an easy access, a standard guide-wire was inserted in the ureter through the renal parenchyma. The kidney was punctured with radiographic or ultrasound guidance. Minimally invasive percutaneous nephrolithotomy (MIP) was then tested using the model under radiographic or ultrasound guidance. The model was then evaluated in MIP training courses, which are regularly held at The Hannover Medical School. RESULTS: All trainees were urologists with experience in endourologic surgery but lacked practice in PRS. In conclusion, all 36 participants attained access to the collecting system using models with readily placed guide-wires. Subsequently, PRS was successful in all cases. Percutaneous puncture under ultrasound guidance and following intrarenal surgery was successful in 30 (83.3%) cases. Therefore, all participants rated the model useful for simulating percutaneous renal surgery. CONCLUSIONS: This new porcine kidney model is easy to build and is made cost effective by using readily available material. Moreover, it provides realistic and reproducible training model for PRS. The "organ" model mimics the retroperitoneum by having a full-thickness skin flap with a layer of subcutaneous fatty tissue.

With only 16 cases reported in the literature, the mostly benign granular cell tumour of the urinary bladder is exceptionally rare. We present the case of a 68-year old patient with one of these lesions demonstrating our histological findings including several immunohistochemical stainings used to differentiate between other more common entities.

AbstractBackground:It has been postulated that laser insertion sheaths prevent mechanical damage to the inside of working channels of flexible ureteroscopes. The presented study, for the first time, aims at confirming this hypothesis and visualized the damage of the endoscopic working channel by video-endoluminal observation after a series of laser fiber passages with or without the protection of a laser fiber insertion sheath.Materials and Methods:Four nonassembled working channels of two different manufacturers (Olympus™, Wolf™) were tested in a deflection model (50° and 180°). Flexifib™ laser fibers (LISA laser products) with an optical core diameter of 273 μm were inserted through 0.9% NaCl irrigated working channels in cycles of 10 insertions either with or without protection of the Flexgard™ insertion sheath. After 30 insertions, the examination cycle was reduced to 5 insertions each cycle until breakage. Test cycles were followed by endoluminal video examination of the working channel with the 2.4F flexible fiber scope by Polydiagnost™. Damage to the working channel was classified as streaks with superficial stress marks of the surface, scratches with embossed margins, or perforations.Results:No scratching or perforation occurred in the insertion sheath group in up to 150 insertions in all working channels and both deflection grades. In the group without insertion sheaths, scratches were visible after 40 to 50 insertions with 50° deflection and 30 insertions with 180° deflection. Perforations of the working channels were seen after 95 insertions with 50° and 60 insertions with 180° deflection.Conclusions:Severe damage to working channels depends on the degree of deflection and may occur after 30 insertions only. Relevant damage to the working channel may be avoided by using a laser fiber insertion sheath. [ABSTRACT FROM AUTHOR]

The brain-specific 42-kDa protein, p42IP4, contains a N-terminal zinc finger (ZF) motif and a tandem of two pleckstrin homology (PH) domains. p42IP4 binds in vitro the second messengers phosphatidylinositol(3,4,5)trisphosphate (PtdIns(3,4,5)P3) and inositol(1,3,4,5)tetrakisphosphate (Ins(1,3,4,5)P4). We observed by confocal microscopy in live HEK 293 cells the GFP-p42IP4, a chimera of human p42IP4 and green fluorescence protein (GFP). There, we studied the influence of thrombin, which raises Ins(1,3,4,5)P4, on membrane translocation of GFP-p42IP4, induced by epidermal growth factor (EGF). Thrombin in the presence of LiCl inhibited the EGF-induced membrane recruitment of GFP-p42IP4. In the absence of LiCl, thrombin weakened the EGF-mediated membrane recruitment of GFP-p42IP4. Furthermore, the participation of p42IP4 protein domains on the EGF-mediated membrane translocation was analyzed. We used several p42IP4 variants, in which one of the domains was deleted. Alternatively, single p42IP4 domain-GFP fusion proteins were generated. Only the p42IP4 variant lacking the ZF domain showed a very weak membrane translocation in response to EGF stimulation, but all the other p42IP4 variants did not translocate. Thus, we conclude that the combination of both PH domains with ZF is required for membrane translocation of p42IP4. [ABSTRACT FROM AUTHOR]