[Stenosis of ureteroneocystostomy: endoscopic resection. A clinical case]. / Stenosi di ureterocistoneostomia: resezione endoscopica. Caso clinico.

The Authors report a case of ureterocystoneostomy sec. Paquin stenosis treated with endoscopic resection of ureteral coupling and of vesical wall with satisfactory results.

Iontophoresis of drugs in the bladder wall: equipment and preliminary studies.

Iontophoresis is the active transport of ions into tissues by means of an electric current: Ji = -D(i)delta Ci/delta chi + DizeECi/kT. Where Ji is the total ionic flux, D(i) the diffusion coefficient, Ci the concentration, z the valency, and E the electric field. The first expression on the right side of the equation is Fick's law of diffusion and approaches zero for bladder mucosa, which leads to uncertain results following intravesical administration of various therapeutic agents. The application of an electric field will potentially accelerate drug administration into the bladder wall in a controllable manner. To evaluate this concept, an appropriate source of electric current and electrodes was fabricated; then, studies were conducted in human cadaveric bladders and clinical trials in human subjects. Ionized dyes were applied in duplicate to 10 fresh cadaveric bladders. Electric currents (3.5-5.0 mA) were applied for 20 min to 10 solutions, and no current was used in 10 controls. Twenty-eight patients had 100 ml solutions of 1% mepivacaine or lidocaine with epinephrine infused into their bladders prior to endoscopic resections. Twenty-two patients received currents of 10-20 mA for 10-20 min, and 6 controls had either no drugs or a current of reverse polarity applied. Visually and on microscopy, the 10 control cadaveric bladder surfaces demonstrated only faint staining of the surface mucosa whereas the experimental surfaces showed full-thickness staining of the mucosa extending into the muscularis. The 6 control patients required supplemental anesthesia or abandonment of the operative procedure. Of the 22 experimental subjects, 16 tolerated procedures with up to 25 g of tissue removed by diathermic resection.

Oxalate, phosphate and sulphate determination in serum and urine by ion chromatography.

A rapid method for the determination of phosphate, sulphate and oxalate in serum by ion chromatography is described. Serum is deproteinized through a Centrifree filter by centrifugation and the ultrafiltrate directly injected into an ion chromatograph equipped with an anion exchange column and a conductivity detector. By this procedure the sample is not diluted and even small amounts of oxalate in biological fluids can be detected. Mean serum concentrations found in healthy individuals are: phosphate 1.07 mmol/l; sulphate 0.35 mmol/l; oxalate 21.02 mumols/l. Phosphate, sulphate and oxalate contents were also determined in urine from healthy individuals. Values found in serum and urine are in good agreement with those previously reported.

Perfusion of uremic blood ultrafiltrate on uncoated charcoal.

A granular uncoated charcoal removes from uremic blood ultrafiltrates many chemical species that are not removed by dialysis. Charcoal treatment dramatically improves the general condition of the patients and normalizes their blood pressure. To obtain a rapid depuration, the initial treatment should be intensive (at least 16 daily treatments) and the effects prolonged over time by once-a-week charcoal treatment between two standard hemodialyses. Biogel P2 chromatography documents well all the events of a depurative treatment that cannot be monitored by hematochemical analyses.

Chromatographic evaluation of perfusion on charcoal in uraemia.

Chromatography on Bio-Gel P-2 and high-performance liquid chromatography on RP-18 columns monitored with UV, fluorescence and electrochemical detectors have been used to evaluate the efficiency of granular, uncoated, active charcoal to remove from the ultrafiltrates of uraemic patients those organic substances accumulated in the blood that are not easily removed by dialysis. Chromatography on Bio-Gel P-2 and high-performance liquid chromatography on RP-18 columns carried out isocratically and monitored with an electrochemical detector seem very useful for clinical investigation as they increase the information obtained from routine haematochemical analyses such as blood urea nitrogen, creatinine, uric acid and electrolytes (calcium, phosphorus, sodium and potassium).

Serum and dialysate aluminium concentration of dialysed patients with chronic renal failure determined by atomic absorption spectrometry with a graphite furnace.

We investigated the aluminium content in water, in solutions for haemodialysis and in serum of patients, under regular haemodialysis using flameless atomic absorption spectroscopy with l'Vov platform. The aluminium content found for tap water was 6-36 micrograms/l. After deionization the aluminium content was negligible. The dialysis bath, prepared with deionized water from a concentrated solution with 30 micrograms/l of aluminium, also showed a negligible amount of aluminium. The results obtained showed that patients who take aluminium orally have predialytic aluminium serum levels between 14 and 68 micrograms/l and between 10 and 66 after dialysis. For patients who do not take aluminium orally, the corresponding values were 12-27 and 12-24. No correlation was found between age, sex, years of dialysis and aluminium serum levels.

Evaluation of blood toxicity in chronic uremia by an improved chromatographic method.

Biogel P2 gel chromatography of ultrafiltrate from chronic uremic patients leads to better resolution of the compounds present than so far reported in the literature. Reproducibility is good. Toxicity, evaluated by cell cultures, was detected in only one chromatographic fraction. Further purification of this fraction with HPLC on a RP18 column revealed two toxic fractions, to the better defined of which a polyol structure was ascribed.

Conventional haemodialysis and ultrafiltration: effects on erythrocyte 2,3-diphosphoglycerate and oxygen affinity in patients with uraemia.

1. The relationship between erythrocyte 2,3-diphosphoglycerate (2,3-DPG) and changes in blood pH and in oxygen affinity were studied in six patients treated with two dialysis techniques: conventional haemodialysis and ultrafiltration followed by conventional haemodialysis. 2. The decrease in erythrocyte 2,3-diphosphoglycerate and increase in pH after conventional haemodialysis may significantly increase the affinity of haemoglobin for oxygen and consequently result in inadequate oxygenation of tissue. 3. Ultrafiltration followed by conventional haemodialysis, on the contrary, is more beneficial for oxygenation of tissue and post-dialysis symptoms may be reduced.

Acid-base equilibrium in Menière's disease.

57 patients suffering from Meiere's disease have been examined: metabolic alkalosis has been found in 39 and metabolic acidosis in 4. Electrolytes (Na, K and Cl) were normal. Among the 31 subjects in the control series a slight metabolic alkalosis qas detected only twice. Follow-up of several patients, from one to three years, resulted in a realization of a parallel between metabolic disturbance and Meniere symptoms. A provocation test, by sodium bicarbonate oral administration, has beem attempted twice: in both instances alkalosis did increase strongly but, only once, vertigo was elicited. Meniere patients found in alkalosis were given acidifying drugs to normalize their acid-base equilibrium. Such treatment proved effective in preventing acute cochleo-vestibular crises and in improving tinnitus and deafness (in the fluctuating stage). On the interruption of treatment symptoms reappeared. The physiological-pathological significance of metabolic alkalosis in Meniere's disease still remains unclear and, consequently, this can be considered merely a predisposing factor in endolymphatic hydrops.