[Trials with a new potentially biodegradable ureteral stent. In vitro results with GX 100-15 LB]. / Versuche zu einer potentiellen bioerodierbaren Ureterschienung. In-vitro-Ergebnisse mit GX 100-15 LB.

We detected a special plastic, which is stable in an acid environment and dissolvable in a basic one. Our preliminary in-vitro results show that the tested material therefore seems principally designed for developing biodissolvable stents for temporary urinary diversion out of the upper urinary tract. Stableness and dissolution could be steered by manipulating the pH.

[Improved tumor stent for internal palliative urinary diversion]. / Neu entwickelter Tumorstent zur internisierten palliativen Harnableitung.

The disadvantages of high flexible endoureteral stents (DJ) in case of tumorinduced extrinsic ureteral compression are due to an insufficient vertical stability of the used stents leading to stent-compression and consecutive hydro- or pyonephrosis. The new developed tumor-stent used in case of tumor-induced ureteral compression is available from 6 to 8 French in diameter and 24 to 32 cm in length. The corpus consists of a combination of high-stability plastics but is of sufficient elasticity in length. Both ends consist of extremely elastic J-parts guaranteeing an exact fixation. As against common DJ's with the same outside-diameter the new stent has a comparable interior diameter and compared to used "old" tumor stents promises a higher interior flow in case of extrinsic diseases. The application can be undertaken in well-known technique, needs no special instrumentation and no learning-curve. To date 52 stents at our urologic departments were placed without any problems, the latest remaining for 15 months. Tumor-induced compression or a higher rate of encrustation could not be seen. All patients tolerated these stents well. In our opinion the new stabilized endoureteral stent can be seen as a better solution instead of percutaneous nephrostomy or frequent stent changing in patients with tumor induced extrinsic ureteral compression.

In vitro results with special plastics for biodegradable endoureteral stents.

Internal ureteral stents are widely used in urologic practice for temporary urinary diversion, but all double-J catheters to date exhibit the same disadvantage; that is, they have to be removed endoscopically, necessitating further intervention. We tested different materials (designated G100X-15xLB and G100X-20xLB) to develop a biodegradable (biodissolvable) endoureteral stent that can be held in place without functional loss yet could be dissolved by changing the environment. The principle of the biochemical background is based on the physiological milieu of the urine. The plastics tested are stable in acidic and dissolve in alkaline conditions. In a first step, specimens of two polymers were placed in artificial urine of different pH over a period of 60 days and monitored for integrity (solution trial). In a second step, artificial urine was set in motion (744 mL/24 hours) an infusion pump (Volumed microVP 5000; Fresenius AG, Bad Homburg vdH, Germany) through an infusion set in which a 30-cm piece of the materials to test had been placed (ureter model). Below the inserted specimen, the lumen of the infusion tube was minimized to make obstruction by fragments more possible. In the solution trial, all specimens remained stable under physiologic conditions (pH 5.2) over a period of at least 30 days. The specimens dissolved completely when the pH was adjusted to an alkaline one (pH 7.9). In the ureter model, with pH values of 7.9, all specimens were decomposed after 20 hours, and no occlusion of the model occurred. Using acidic artificial urine, the specimens remained stable with a smooth consistent surface. The dissolution was not a standard chemical one; the materials broke into microscopically small pieces, with fragments of G100X-20xLB being smaller than those of G100X-15xLB. Our first in vitro results show that the tested materials are suitable for further development of biodissolvable endoureteral stents, dissolution of which can be steered by changing the urinary pH.

New endoureteral double-J stent resists extrinsic ureteral compression.

The disadvantages of highly flexible endoureteral (double J) stents in the face of tumor-induced extrinsic ureteral compression are a consequence of insufficient cross-sectional stability, leading to stent compression and thus to hydronephrosis or pyonephrosis. The newly developed tumor stent, which is used in cases of tumor-induced ureteral compression, is available in sizes from 6F to 8F in diameter and 24 to 32 cm in length. The shaft consists of a combination of high-stability plastics that presents sufficient elasticity in length. Both ends are made of extremely elastic J parts, guaranteeing stable fixation. Compared with common double-J stents with the same outside diameter, the tumor stent possesses a comparable interior diameter and compared with available stents promises sufficient interior flow in the face of extrinsic diseases. The application can be undertaken using well-known endoscopic techniques, needs no special instrumentation, and entails no learning curve. To date, 49 stents were placed at our urologic departments without any problems, the latest stent remaining for 15 months. Tumor-induced compression or a higher rate of encrustation were not seen. All patients tolerated these stents well. In our opinion, the new stabilized endoureteral stent can be seen as a better solution than percutaneous nephrostomy or frequent stent changing to tumor-induced extrinsic ureteral compression.

Potentially useful materials for biodegradable ureteric stents.

OBJECTIVES: To develop and test materials that may be useful in the design and further development of biodegradable ureteric stents. MATERIALS AND METHODS: Specimens of two plastics were placed in artificial urine of different pH for 30 days to examine the degree of dissolution of the plastic in alkaline and the stability in acidic conditions. RESULTS: The specimens remained stable in the artificial urine at pH < 7.0 for 30 days and dissolved completely at a pH > or = 7 within 48 h. CONCLUSION: Plastics can be designed which may be useful in the further development of biodegradable ureteric stents. The rate of dissolution could be changed by influencing urinary pH.

[Modulith SL 20. One-year urologic experience with a lithotripter of the third generation]. / Modulith SL 20. Urologische Erfahrungen über ein Jahr mit einem Lithrotripter der dritten Generation.

The MODULITH SL20 combines on-line ultrasound and optional X-ray in series. In addition to highly simplified patient positioning and the possibility of handling the machine as a multipurpose lithotripter for disintegration of urinary-, gallbladder and bile duct stones and for treatment of pancreatic concrements this appliance can be used in cases of sialolithiasis and as a workplace for all urological purposes, so that the design is very modern. As the energy level in f2 can be extremely high, a disintegration rate of about was achieved for 70% ureteral stones in the middle and distal sections of the ureter. However, this good disintegration rate was not achieved for ureteral stones lying in the upper ureter or in cases of nephrolithiasis treated with a prototype of the machine. In our opinion, this reflects a problem with nonexistent on-line X-ray stone localization, but an overall disintegration rate of about 77% in preselected patients (1.8 stones/patient) confirms that this is a highly sophisticated and powerful machine.

Efficacy, risks, and limits of extracorporeal shock wave lithotripsy for salivary gland stones.

Stones of the salivary glands may cause recurrent swelling, ascending inflammation, and colic-like pain. Previously, in order to get rid of these stones, the gland usually had to be removed surgically in spite of the associated risks to adjacent structures, especially the facial nerve. We treated 104 salivary gland stones in patients 14 to 78 years old using the Storz Modulith SL 10 lithotripter. Each session (average 3.6 per patient) consisted of 1000 impulses at 2 Hz and 16 to 18 kV. No anesthesia was required. Earplugs were applied to patients being treated for parotid gland stones. With the aid of SWL and drug-induced salivation, 17 (59%) of the patients with parotid gland stones and 42 (56%) of those with submandibular gland stones obtained either total stone clearance or sufficient fragmentation to permit spontaneous passage. Four patients required surgery. The remaining patients are still being treated. The noninvasive SWL for salivary gland stones is noninvasive and painless and has a considerable success rate. It can be performed on an outpatient basis.

Orchitis following mumps vaccination in an adult.

An acute epididymo-orchitis, followed by a viral arthritis of the left hand, occurred as complications of a mumps vaccination. In the last 17 years 4 certain cases of orchitis following vaccination have been published in Germany. We describe an additional case and discuss the possible consequences.

Effects of magnesium citrate and phytin on reducing urinary calcium excretion in rats.

The aim of this study was to determine and compare the effects of both magnesium citrate and phytin on reducing urinary calcium excretion under high-calcium-diet conditions during single and combined treatments. An animal experiment was carried out over a period of 4 weeks in 35 male rats. Urinary calcium excretion was reduced significantly by magnesium citrate and/or phytin in rats fed on high-calcium diets. The hypocalciuric effect of magnesium citrate was more evident than that of phytin. Urinary magnesium excretion was high in all experimental groups. However, the urinary magnesium/calcium ratios showed a consistent increase only in the groups treated with magnesium citrate. Urinary citrate excretion showed a relative increase with the introduction of magnesium citrate plus phytin; however, in both the high-calcium-diet group and the magnesium-citrate group this was found to be reduced. Urinary phosphate excretion was slightly higher in the groups treated with phytin. There was no definite difference in urinary oxalate concentration between the groups. No significant change was noted in the serum concentration of calcium, magnesium, or phosphate.

[The therapeutic value of ambulatory extracorporeal shockwave lithotripsy of salivary calculi. Results of a prospective study]. / Die therapeutische Wertigkeit der ambulanten extrakorporalen Stosswellenlithotripsie von Speichelsteinen. Ergebnisse einer prospektiven Studie.

In a prospective study, results of the extracorporeal shock wave lithotripsy of salivary stones were evaluated. The study was performed with the currently available technical possibilities of electromagnetic systems to get indication criteria for this procedure. Using the Modulith SL 20-lithotripter of Storz Medical AG, 33 concrements in 25 patients were treated in 89 lithotripsy sections. The stone sizes, localized by ultrasound, ranged from 3 to 13 mm diameter (phi 6.9 mm). After application of local anaesthesia, per session on an average 1300 shock waves with raising energy levels were applied, the succession of shocks fixed to 1 MHz. With the help of ultrasound localisation, a therapeutic success with complete emission of the concrement or an adequate disintegration of these stones could be achieved in 82% of the parotid gland stones (n = 11) and in 14% of the submandibular gland stones (n = 22). Since the unhampered functioning of these salivary glands is an inevitable pre-condition for the spontaneous emission of the disintegrated fragments, the status of function of salivary glands should be established by a scintigraphy before performing the ESWL. Even though complete emission of the stone could be achieved in only 4 patients, all patients were clinically free of symptoms after the treatment. In 3 of 25 patients, discrete bleeding of a passing nature occurred coming from the salivary duct. In 2 patients, formation of haematoma of varying dimensions could be visualized by ultrasound. 3 patients showed petechial skin bleeding. The tinnitus aurium which affected one patient eased after 3 days. In our patients collective a facial nerve damage did not occur.2+ longterm prognosis after this procedure.

[ESWL in hemophilia B]. / ESWL bei Hämophilie B.

One of the most dramatic dangers in treating nephrolithiasis by ESWL is the development of intra- and perirenal bleeding, which requires therapeutic intervention. Even in patients whose blood parameters suggest they are healthy, hematomas are found in up to 80%. Therefore, ESWL must be regarded as contraindicated in patients with blood disorders. A case of a patient suffering from hemophilia B and from a large renal pelvic stone is reported, whom we treated by ESWL twice after sufficient substitution. X-ray revealed that the patient was stone-free on the 25th day after the first ESWL session. ESWL. A review of the literature is presented.

Metastatic renal cell carcinoma (RCC): spontaneous regression, long-term survival and late recurrence.

We report 4 cases of metastatic renal cell carcinoma (RCC) with long-term survival either following radical nephrectomy alone or in combination with radio- or hormonal therapy. Two patients with lymph node metastases showed a long-term survival of 12 or more years following radical tumour nephrectomy (with lymphadenectomy) and radiotherapy. One of them exhibited a histologically proven tumour recurrence nearly 12 years after primary surgical treatment and died shortly later; the other one is still without any evidence of metastatic disease. Two other patients exhibited spontaneous regression of pulmonary metastases: one regression occurred after radical tumour nephrectomy alone, the other one after successful primary hormonal treatment and subsequent radical tumour nephrectomy. The following important aspects are emphasized: 1. Renal cell carcinoma is a very unpredictable tumour. Once the diagnosis of renal cell carcinoma is proved, a patient can never be considered cured. 2. Although adjuvant palliative nephrectomy has produced contradictory results in several reports, radical tumour nephrectomy either alone or in combination with other adjuvant therapies such as radiotherapy, hormonal or immunological treatment, can be worthwhile. Cases with long-term survival and spontaneous regression of distant metastases are proof of this. Besides, if carefully selected, the mortality rate of different adjuvant therapies is not significantly higher in patients with metastatic disease than in patients without metastases. The world literature on this subject is reviewed.

In vitro sensitivity testing of human renal cell carcinoma with cytostatic agents and interferon alpha-2a.

Samples of 38 human renal cell carcinomas (RCC) were subjected to routine histopathological examination but also to in vitro sensitivity testing with mitomycin C, vinblastine and interferon Alpha-2a at various concentrations corresponding to serum titers recommended to be effective in vivo, employing a monolayer assay. Extending earlier in vitro studies, both tumor cell kill rates (TCKR) and proliferation rates (PR) were assessed. Following in vitro preparation the tumor cell cultures were simultaneously exposed to the anticancer drugs listed above. The proliferation rates were determined immunocytochemically using the monoclonal antibody Ki-67. Nine (23.7%) of the tumors investigated revealed temporary and limited response with respect to either TCKR or PR. Improvement of this percentage could only be obtained by increasing drug concentration to titers with toxicity intolerable for in vivo administration. The in vivo data presented correspond to clinical temporary and limited remissions in patients with metastatic RCC ranging up to 25%.

Antiproliferative activity of picolinic acid due to macrophage activation.

Activation and subsequent enhancement of cytotoxicity of mouse peritoneal macrophages (M phi) by picolinic acid (PLA) in vivo have been reported previously by the authors' group. The optimum dose was found to be 100 mg/kg. PLA-stimulated M phi lysed different tumor targets in vitro, MBL-2 lymphoma cells and Madison 109 lung carcinoma cells, with equal efficiency. Treatment with PLA was performed daily for 5 consecutive days with a dose of 100 mg/kg intraperitoneally in C57/BL mice, which previously had been inoculated with MBL-2 tumor cells. Treatment was initiated on the first day after tumor inoculation. Oral treatment with PLA (200 mg/kg) dissolved in the drinking water was also performed for 7 days. In addition, some groups received PLA treatment 1 or 2 days before tumor implantation but not afterwards, to elucidate the in vivo efficacy of M phi activation. Intraperitoneal therapy with PLA after tumor inoculation resulted in a highly significant increase in lifespan (46%); intraperitoneal pretreatment caused a significant increase (15%); orally administered PLA was without effect. Thus intraperitoneal treatment with PLA was found to have protective and therapeutic effects against the MBL-2 ascites tumor in vivo. These effects are most likely caused by macrophage activation.