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BACKGROUND: The aim of treatment of patients with colovesical fistulas should be prompt elimination of the infection and the social burden. We focused on the question whether a minimally invasive surgical approach as a cooperation between surgeons and urologists is possible. This requires effective diagnostics prior to the operation. METHODS: Since 2007 a total of 32 patients with the clinical suspicion of colovesical fistula have undergone extensive preoperative diagnostics. Operative treatment aimed primarily for a minimally invasive approach. In particular, the validity of preoperative diagnostics was analyzed and surgical results were characterized by clinical success, complications and long-term effects. RESULTS: The medical history significant for colovesical fistula and detected urinary infection provided the best evidence for the specific diagnosis. Cystoscopy, computed tomography (CT) scan and colonoscopy were only partially effective for predicting a fistula as subsequently diagnosed by histopathological investigations. Fistulas due to diverticulitis of the sigmoid colon occurred in 28 cases, while in 3 subjects there was a gynecological and inflammatory cause (malignant tumor growth, n = 1). A laparoscopic approach achieving repair and healing of the fistula was possible in 29 cases including conversion in 3 subjects because of intraoperative complications. The remaining patients underwent conventional treatment. The disease-related complication rate as revealed during follow-up was 10%. DISCUSSION: Laparoscopic repair and healing of a colovesical fistula is possible in the majority of cases by the recommended preoperative ureteral stenting. As part of diagnostic measures, the medical history significant for a fistula and detection of urinary infections are the most reliable aspects. In the case of this combination together with a further diagnostic measure, a laparoscopic approach is always recommended. The recurrency rate is 0%.

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The self-assembling behaviour of 2.6 nm thin PbCO3 nanoplatelets with discorectangular shape and uniform width and thickness occurring after their formation in nonionic water-in-oil microemulsions has been investigated using synchrotron small angle X-ray scattering (SAXS) and (scanning) transmission electron microscopy ((S)TEM). The presence of attractive depletion forces originating from the ubiquitous microemulsion droplets triggers a new type of superstructure at low particle concentration. Instead of the universally observed formation of face-to-face assembled lamellar mesostructures, the nanosheets self-organise into extended ribbon structures, whereby each on top lying sheet is displaced by a constant shift in the length and width directions leading to a so far unprecedented staggered zigzag-type stack assembly with restricted height. This type of stacking gives rise to a complex interference pattern in the isotropic small angle scattering of the stacked ribbon assemblies (SRAs) in reverse micellar solution. Different to the, for lamellar-structured nanosheets typical, diffraction peaks at multiples of the wave vector corresponding to one particular repeat distance, the scattering peaks measured in this study are asymmetric, displaying a shoulder on their low wave vector side. The asymmetric shape of the observed face-to-face correlation peaks indicates that the SRAs do not extend in one direction only. Their scattering behaviour is analysed by expanding the Kratky-Porod structure factor for stacking plates into three dimensions. High-angle annular dark-field (HAADF)-STEM tilt series have complementary been acquired to retrieve three-dimensional structural information on the SRAs in the dry state and to confirm the model used for the refinement of the SAXS data.

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We report on the technology and growth optimization of GaAs/InAs core/shell nanowires. The GaAs nanowire cores were grown selectively by metal organic vapor phase epitaxy (SA-MOVPE) on SiO(2) masked GaAs (111)B templates. These were structured by a complete thermal nanoimprint lithography process, which is presented in detail. The influence of the subsequent InAs shell growth temperature on the shell morphology and crystal structure was investigated by scanning and transmission electron microscopy in order to obtain the desired homogeneous and uniform InAs overgrowth. At the optimal growth temperature, the InAs shell adopted the morphology and crystal structure of the underlying GaAs core and was perfectly uniform.

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The ammonolysis of beta-Ga(2)O(3) to alpha-GaN and the oxidation of alpha-GaN to beta-Ga(2)O(3) have been studied by means of in situ X-ray absorption spectroscopy (XAS), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). In situ X-ray absorption measurements on polycrystalline powder particles on the gallium K-edge during both reactions give detailed information about the reaction kinetics. We were able to extract this kinetics by fitting linear combinations of beta-Ga(2)O(3) and alpha-GaN spectra only. The kinetics of the ammonolysis can be described well by an extended Johnson-Mehl-Avrami-Kolmogorow model, while the oxidation kinetics can be modelled by a shrinking core model. Investigations by means of TEM and SEM support the assumptions in both models. Our experimental results and the models are discussed in terms of the reaction energetics and the reaction mechanisms.

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BACKGROUND: After long term clinical training at teaching hospitals, individuals or complete teams have reported on the establishment of laparoscopic nephrectomy and prostatectomy. This, however, is difficult to realize at many clinics due to the current staffing situation. In the following an alternative approach will be presented. METHODS: After 50 hours of practice on a pelvic trainer during which the laparoscopic handling and especially various suturing techniques were learnt (A) a total of 15 pigs (approx. 40 kg, in general aesthesia, right sided positioned, with 7 ports) have been operated from February to August 2006: 1. laparoscopic nephrectomy, 2. laparoscopic in-situ cold perfusion, 3. laparoscopic renal autotransplantation (B). Directly after this a two month clinical training at a recognized laparoscopic center took place (C). RESULTS: After completion of phase A, an extended experimental operation phase B followed, marked by complications such as: bleeding (n=5), skin emphysemas (n=3), technical failures (n=2), non-optimal placement of ports (n=6), problems with placement the cold perfusion catheters (n=7), and unsuitable surgical instruments (n=2). Eleven laparoscopic nephrectomies were successful; only during the last three operations a sufficient end-to side anastomosis has been achieved (anastomosis time range 80110 min of which was 50% in cold ischemia). During the external clinical training (C) (through 2. and 1. assistance) five endoscopic extraperitoneal prostatectomies (surgery time range 145-235 min) and two radical nephrectomies have been independently carried out (180-230 min). CONCLUSIONS: Using the pig model laparoscopic renal autotransplantation ideally combines ablative and reconstructive operation techniques. For this reason it is especially suitable for young urologists learning to perform nephrectomies and prostatectomies. For beginners in laparoscopy this entails long but mentor independent learning phases A, B thereby shortening the subsequent clinical training at the teaching hospital (C).

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PURPOSE: The purpose of this study was to evaluate the results and complications of percutaneous nephrolithotomies performed within 5 years in our patients. MATERIALS AND METHODS: From 2001 to 2005 in our department 158 percutaneous nephrolithotomies (PNL) in 131 patients and 138 renal units were performed. The indications for PNL were calculus greater than 2 cm, failed ESWL, and when there is additional urinary obstruction which was not caused by the stone itself. Data concerning past medical history, about the procedure including complications and the postoperative course were collected and evaluated. RESULTS: 87 (63 %) of the patients had a history of prior stones. The main symptoms were flank pain, recurrent renal colic and urinary tract infection. The stones treated had a size from 5 to 60 mm. In 40 patients (29 %) relief of urinary obstruction (double-J-ureteral stent or percutaneous nephrostomy) or ESWL was performed prior to PNL. Mean operating time was 83 (30 - 235) minutes including retrograde placement of a ureteral catheter and nephrostomy. Complications occurred in 26 (16.5 %) procedures. Severe complications were: one fatal pulmonary embolism, one septicaemia, three open revisions (including one nephrectomy) and four blood transfusions for blood loss. In 94 patients (68 %) there was no residual stone or gravel after the first PNL. No further therapy was necessary in 17 (39 %) of the 44 patients with incomplete stone removal. 19 patients underwent a secondary PNL. In these procedures the efficacy decreased. 102 of 131 patients (138 renal units = 73.9 %) were discharged without residual stone after 158 procedures. CONCLUSIONS: PNL is an efficient and rarely complicated procedure for larger stones of the upper urinary tract. Even so, the occurrence of severe complications must be considered. Complications can be minimised by the use of a standardised therapeutic pathway.

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Energy-filtered Debye-Scherrer electron powder data have been successfully employed to determine the structure of nanocrystalline anatase (TiO2). The performed structure analysis includes determining the unit cell, space group, solving the structure via direct methods from extracted intensities and refining the structure using the Rietveld technique. The refined structural parameters for space group I4(1)/amd are a = 3.872 (2), c = 9.616 (5) A with titanium at 0.5,0.75,0.375 and oxygen at 0.5,0.75,0.1618 (6). The obtained structure indicates low internal stress as judged from the almost regular geometry of the TiO6 building blocks. Striking resemblance with the anatase structure determined previously by Burdett, Hughbanks, Miller, Richardson & Smith [J. Am. Chem. Soc. (1987). 109, 3639-3646] from neutron diffraction on coarse-grained material gives strong support for the correctness of the structure determined here. The result of the present study shows that the methods originally developed for determining structures from X-ray powder data work equally well with data from electron powder diffraction. This may open the window for structural investigations on the vast number of nanocrystalline materials and thin films whose structures are difficult to determine by X-ray diffraction since they are frequently only available in small quantities.

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OBJECTIVES: To evaluate the diagnostic potential of echo-enhanced ultrasonography (US) for depicting the vascularization pattern of renal cell carcinoma (RCC), and calculating the first-pass effect using harmonic imaging, against that obtained by triphasic helical computed tomography (CT). PATIENTS AND METHODS: Sixty patients with surgically confirmed RCC underwent US using B-mode and power Doppler methods with or without an intravenous microbubble echo-enhancing agent. After depicting and defining the tumour extent by B-mode US, the first-pass effect/enhancement by the echo-enhancing agent within the lesion, and that of a reference area of unaffected renal cortex, were recorded on-line by calculating the mean pixel intensity. Time-intensity curves, i.e. the rise time and gradient of both the suspected tumour and reference areas, were constructed. RESULTS: Using B-mode US, the extent of all tumours was delineated (mean tumour size 3.8 cm, SD 0.6). After applying the microbubble agent all tumours were enhanced, whereas the perfusion was decreased (in 48%), increased (in 16%) or similar (in 36%) compared with the cortical reference area. Using the Hounsfield classification, these results correlated well with the hypo/hypervascularity shown on CT. CONCLUSION: Ultrasonography has considerable potential in diagnosing RCC, if combined with echo-enhancing methods, harmonic imaging and computer-based calculation of tumour vascularization. Dynamic US studies should provide a diagnostic yield similar to that of CT.

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A 60-year-old woman was treated for severe interstitial cystitis pain using sacral nerve stimulation. Pain and accompanying bladder dysfunction were improved by temporary and permanent sacral nerve stimulation. Six months after implantation of a sacral neuromodulator the patient is pain free and significantly improved on bladder dysfunction. Interstitial cystitis may be an indication for functional electrostimulation.

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The structure of a new modification of Ti2Se, the beta-phase, and several related inorganic crystal structures containing elements with atomic numbers between 16 and 40 have been solved by quasi-automatic direct methods from single-crystal electron diffraction patterns of nanometre-size crystals, using the kinematical approximation. The crystals were several thousand times smaller than the minimum size required for single-crystal X-ray diffraction. Atomic coordinates were found with an average accuracy of 0.2 A or better. Experimental data were obtained by standardized techniques for recording and quantifying electron diffraction patterns. The SIR97 program for solving crystal structures from three-dimensional X-ray diffraction data by direct methods was modified to work also with two-dimensional electron diffraction data.

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We report a case of long-standing dysuria due to silent surgical abscess disease. The cause of our patient's complaint was not expected because we focused on dysfunctional voiding and not dysfunction as result of pathology close to the bladder neck since the history given by the patient was unremarkable.

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The need for research in prevention has never been greater, while the support for such research is declining. A partnership between prevention practitioners and researchers is recommended. To play an active role in this resource network practitioners must learn more about the applied research process. This paper describes the major phases of that process and discusses the decisions which practitioners must make at each research step. The paper makes recommendations for conducting research on a shoestring budget and emphasizes special problems encountered in field settings.

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This study examines the relationships between ideology and service delivery performance in an established community mental health center which is beginning major structural changes. Ideological pluralism among several separate and internally-cohesive units within one organization led to diversity in staff productivity. The implications of ideological pluralism for planned organizational change, policy implementation and administration are explored.

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