Epidemiology of end-stage renal disease and current status of hemodialysis in Yugoslavia.

Maintenance hemodialysis (HD) in Yugoslavia started in the sixties and followed the dialysis trends in the Western Europe. However, in the last decade the development of renal replacement therapy (RRT) slowed down. In this report the epidemiology of ESRD from 1997-1999 and the survey of the status of HD treatment in Yugoslavia in 1999 are presented. Epidemiological data are obtained by the annual center questionnaires (response rate: 92.6 -94.2%). The survey of HD status is based on a specific questionnaire and covered 2108 patients (65%). At the end of 1999 there were 56 RRT centers in Yugoslavia treating 3939 patients: 3232 (82%) patients by HD, 248 (6.3%) by peritoneal dialysis, and 459 (11.7%) living with transplanted kidney. In a three year period, incidence of ESRD ranged from 108-128 pmp, point prevalence from 435-463 pmp and mortality rate from 20.7-17.9. Numerous refugee patients were treated over the last 10 years. Main causes of ESRD were glomerulonephritis (30%); Balkan nephropathy represented 11% and diabetic nephropathy 7% of all primary renal diseases. Cardiovascular and cerebrovascular diseases were the most common causes of death of RRT patients. Most centers are overcrowded and HD machines are worn out. Mean Kt/V was 1.19+/-0.08, mean URR% 58.8+/-7.4. The shortage of drugs prevented adequate management: 83% of HD patients had hemoglobin level less than 100 g/L but only 10.3 -17.8% were treated with rHuEpo; 64.5% of patients had phosphate levels higher than 1.7 mmol/L but only 33.5% used phosphate binders; 47% of patients had hypertension despite the antihypertensive therapy. The prevalence of hepatitis B remained unchanged (about 14%) in HD population during the last three years, but the prevalence of anti-HCV positive patients decreased (31-23%). In conclusion, there is a well developed dialysis service in Yugoslavia but insufficient conditions for adequate treatment.

Chromophoric and fluorophoric peptide substrates cleaved through the dipeptidyl carboxypeptidase activity of cathepsin B.

The action of bovine spleen cathepsin B as a dipeptidyl carboxypeptidase on newly synthesized substrates of the type peptidyl-X-p-nitrophenylalanyl (Phe(NO2))-Y (X,Y = amino acid residue) or 5-dimethylaminonaphthalene-1-sulfonyl (Dns)-peptidyl-X-Phe(NO2)-Y was investigated. The kinetic parameters of hydrolysis of the X-Phe(NO2) bond were determined by difference spectrophotometry (delta epsilon 310 = 1600 M-1 cm-1) or by spectrofluorometry by following the five- to eightfold increase of Dns-group fluorescence with excitation at 350 nm and emission at 535 nm. The substrates were moderately sensitive to cathepsin B; kcat varied from 0.7 to 4 s-1 at pH 5 and 25 degrees C; Km varied from 6 to 240 microM. The very acidic optima of pH 4-5 are characteristic for dipeptidyl carboxypeptidase activity of cathepsin B. Bovine spleen cathepsins S and H had little and no activity, respectively, when assayed with Pro-Glu-Ala-Phe(NO2)-Gly. These peptides should be a valuable tool for routine assays and for mechanistic studies on cathepsin B.