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O Schück

Publications and source records attributed to O Schück.

At least 19 recordsLinked to original sources
PubMed1995

[A nutritionally defined liquid diet for hemodialyzed patients].

BACKGROUND: For patients having regular haemodialysis there are no suitable complete preparations for general use in case intensive treatment is needed. Nutrilac renal is a new preparation of a nutritionally defined liquid diet corresponding as to its composition to the needs of haemodialyzed patients. The purpose of the present work was to assess whether this preparation when administered as a supplement will have a favourable effect on the nutritional parameters of haemodialyzed patients. METHODS AND RESULTS: Nutrilac renal was administered to haemodialyzed patients for a period of three weeks as a supplement meeting 20% of the energy requirements. The protein intake rose from 0.87 to 0.95 g/kg body weight (p < 0.05), the energy intake from 109 to 126 kJ/kg body weight (p < 0.05). As to nutritional parameters, the serum albumin values improved (from 25.0 to 29.4 g/l, p < 0.05) and Whitehead's quotient from 1.8 to 1.5, p < 0.05). The favourable effect on the amino acid spectrum was manifested by a significant rise of essential amino acids and those with branched side chains (p < 0.01). The preparation did not lead to a rise of potassium, ura and vitamin A levels. CONCLUSIONS: The newly developed preparation Nutrilac renal exerts a favourable effect on nutritional parameters. Changes in the aminogram characterized by an increase of essential amino acids, in particular threonine, valine, leucine and isoleucine indicate the high biological value of the protein component of the preparation for patients with chronic renal failure.

Amino Acids↗
PubMed1995

[Kinetics of phosphorus in individuals on regular dialysis therapy].

In eight subjects with hyperphosphataemia included in regular dialyzation treatment repeatedly phosphorus kinetics (iP) were assessed based on changes in serum concentrations and the amount of iP removed from the organism during every dialysis (D). The serum concentration of iP before dialysis (HD) was on average 3.06 (+/- 0.81) mmol/l and D was on average 55.6 (+/- 10.0) mmol. The value of D calculated per body weight (D/BW) was on average 0.76 (+/- 0.15) mmol/kg. As the differences of predialysis serum concentrations of iP after consecutive HD sessions did not exceed the range of error of analytical assessment of iP, the D values were considered identical with the iP value retained during the interdialysis interval (R). Between values of D/BW and R/BW resp. and the difference of iP serum concentrations at the beginning and end of the interdialyzation interval a significant direct correlation was found (r = 0.715, p < 0.001). From an analysis of this correlation ensues that if the predialysis serum concentration is not to exceed the upper range of the normal value (1.7 mmol/l), the retention of iP in the interdialysis interval must not significantly exceed the value of 0.57 mmol/kg. At the end of the interdialysis interval iP was distributed in the organism in such a way that the extracellular space contained on average 0.38 (+/- 10) from the total retained amount and the remaining portion penetrated into deeper body compartments.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[An experimental model of the effect of uremia on cyclosporin A availability].

BACKGROUND: The aim of the study was to determine whether or not uraemia has an effect on cyclosporine A intestinal resorption. METHODS AND RESULTS: Model experiments were conducted in rats to monitor the effect of acute uraemia (bilateral nephrectomy) on the kinetics of cyclosporine A. Using intragastric tube, Cyclosporine A was administered to one group of rats in the form of Consupren (Galena, Czech Republic) and to another group in the form of Sandimmune (Sandoz, Switzerland), at a dose of 10 mg/kg/24 h either case. Blood levels of cyclosporine A were determined using RIA and specific and non-specific antibodies (cyclosporine and its metabolites). Cyclosporine A kinetics in nephrectomized rats was compared with that in control rats and in rats undergoing sham nephrectomy. The blood levels of cyclosporine A were significantly lower, and the area under the curve (AUC) of blood cyclosporine A in nephrectomized rats significantly smaller than in control rats. No significant differences in the evaluated parameters after Consupren or Sandimmune were observed. CONCLUSIONS: Our findings support the hypothesis that uraemia decreases cyclosporine A availability. The results suggest that the changes in cyclosporine A kinetics in nephrectomized rats following Consupren and Sandimmune administration are of the same character.

Acute Disease↗
PubMed1994

[Changes in amino acids in a regular dialysis program].

BACKGROUND: Dialyzed patients are chronically in a state of negative nitrogen balance, and amino acids, their building stones, are also significantly affected by dialysis. The purpose of the present investigation was to assess whether they should be supplied, how frequently and for how long and how they are influenced by the usual diet of patients. METHODS AND RESULTS: The examination was made in a group of 13 patients included in a regular haemodialysis programme. Their mean age was 53.2 +/- 12.4 years, they were dialyzed for an average period of 55 months, maximum 163 months. The patients were dialyzed three times per week for four hours, bicarbonate dialysate was used. The patients' diet was not modified in any way. A total of 52 haemodialysis were examined: losses of alpha-amino nitrogen were monitored as well as changes of serum concentrations of different amino acids. Their mean losses were 119 +/- 54.69 mmol/4 h: this corresponds to 10.5 +/- 4.8 mg amino acids. The dialysis clearance was on average 122.7 +/- 63.2 ml/min. This value did not differ significantly from the dialysis clearance of urea, but it was significantly higher than creatinine clearance (p < 0.05). During dialysis a significant drop (p < 0.001) of the plasma concentration of amino nitrogen occurred, however, the changes of serum concentrations of amino acids differed. A significant drop was recorded in serum concentrations of histamine, lysine, cysteine, methionine, tyrosine, glycine, asparagine, citrullin, glutamine, taurine. Before the beginning of dialysis the values of valine, lysine, threonine, serine, alanine and asparagine were lower than corresponds to the reference interval in healthy subjects. CONCLUSIONS: Changes of serum concentrations of individual amino acids are significantly influenced not only by their losses into the dialysate but also by their shift from cells into the extracellular fluid and by resorption from the digestive tract during protein intake in the course of dialysis. An adequate supply of high quality protein can compensate for these losses. Investigation of serum concentration of individual amino acids does not record their kinetic changes but can give an idea on the effectiveness of the dietary regime.

Amino Acids↗
PubMed1994

[Comparison of the effects of 2 preparations of cyclosporin A-- Consupren and Sandimmune--from the aspect of functional and morphologic changes in rats with renal ischemia].

BACKGROUND: Cyclosporine A is in transplantology an irreplaceable immunosuppressive agent. Its only manufacturer preparation Sandimmune--was the Swiss firm Sandoz. In 1990 the Czech firm Galena introduced cyclosporine A with the name Consupren on the market. The objective of the present investigation was to assess whether the nephrotoxic effect of the two preparations is comparable, or whether it differs. METHODS AND RESULTS: In a group of 65 rats after unilateral nephrectomy and 45-minute ischaemia of the remaining kidney the nephrotoxic action of cyclosporine preparations Sandimmune (Sandoz) and Consupren (Galena, CZ) administered in doses of 10 mg/kg body weight/24 hours throughout the experiment was investigated. The functional and morphological examination was made 3 or 21 days following nephrectomy. After three days the serum levels of creatinine, urea, sodium, osmolality and their urinary excretion as well as the intensity of proteinuria and morphological findings using light and electron microscopy did not differ in the two groups. The same was found during follow-up after 21 days; the small difference in the serum creatinine level only (Sandimmune 96.0 +/- 9.7 mumol/l, Consupren 111.4 +/- 11.2 mumol/l; p < 0.005) may be associated with the significantly higher cyclosporin levels following Consupren administration. CONCLUSIONS: The findings of the investigation support the idea that even after ischaemic kidney damage the nephrotoxicity of Consupren is not higher than that of Sandimmune.

Animals↗
PubMed1994

[Individualized supplemented low-protein diet in patients with chronic kidney failure].

The possibility of developing protein-energy malnutrition poses a serious risk associated with long-term administration of a restrictive low-protein diet. We conducted a randomized prospective study designed to evaluate 36 patients with chronic renal failure in initial malnutrition (BMI 22%, albumin 35 milligrams, WQ 2.02). In 20 of these patients (Group I), low-protein diet was supplemented with ketoanalogs of essential amino acids along with a low-phosphate drink from casein-free protein. The diet of another 16 patients (Group II) was supplemented with a mixture of essential and non-essential amino acids of egg white. Three-month follow-up revealed a statistically significant improvement in selected metabolic parameters (Surea, albumin, WQ, valine HDL-CH cholesterol, SP and SCa), particularly in Group I (p < 0.01). In group II, the improvement was either not marked (p < 0.05) or no improvement was seen. Results of the study indicate that patients found to suffer from initial malnutrition require early dietary supplementation including ketoanalogs of essential amino acids and a special protein providing an adequate amount of energy.

Adult↗
PubMed1994

[Renal clearance of hippurate in persons with chronic renal insufficiency].

In 8 subjects with chronic renal failure treated conservatively the renal hippurate clearance (CHip), polyfructosan (CPF) and creatinine (Ccr) clearance was assessed. The mean values of the investigated variables were as follows: CHip = 1.06 +/- 0.79 ml/s, CPF = 0.15 +/- 0.08 ml/s, Ccr = 0.27 +/- 0.17 ml/s. The ratios between the investigated clearance values were: CHip/CPF = 6.9 +/- 4.2 and CHip/Ccr = 4.2 +/- 1.4. The ratio of CHip/CPF was in some instances as high as 10 or more. Between values of CHip/CPF and the plasma hippurate concentration (PHip) a significant negative (non-linear correlation was found (p < 0.01). When the PHip values were very high, the value of the CHip/CPF ratio was close to 1. The recorded findings confirm that in subjects with chronic renal failure in the residual nephrons hippurate is synthetized and its urinary excretion in relation to glomerular filtration is increased. The findings suggest also that in these patients the tubular transport for hippurate is saturated. It will be necessary to take into account the possible saturation of tubular transport for hippurate when interpreting changes of drug excretion (i.e. those excreted by the same mechanism as hippurate) in subjects with chronic renal failure.

Adult↗
PubMed1994

[Renal excretion of amino acids in patients on a regular dialysis program].

In 10 patients with chronic renal failure and a polyfructosan S clearance (CPFS): 1.91-12.70 ml/min (mean 5.68 ml/min) with a preserved residual diuresis (more than 1000 ml/24 hours) renal excretion of 22 amino acids by residual nephrons was investigated before and 12 hours after haemodialysis. It was revealed that 12 hours after haemodialysis a significant drop of the filtered amount of all investigated amino acids occurred. Renal clearance of Ser, Pro, Glu, Gly, Ala, Tyr, Met, Leu and Cit after haemodialysis declined significantly (p < 0.05-0.001). Haemodialysis was not associated with significant changes of fractionated excretions (FE) of amino acids with the exception of Gly (p < 0.01) and Trp (p < 0.05) where an increase of FE was recorded. Hitherto assembled results are consistent with the idea that a reduction of the tubular resorption of amino acids in the residual nephrons in subjects with chronic renal failure cannot be explained by a change of their filtered amount (as "overflow" aminoaciduria) nor as the consequence of retention of some dialyzable substances which could inhibit tubular transport of amino acids. The reduced tubular transport of some of the investigated amino acids (Cys, Lys, Cit, Met, Asn+Gln, Orn, Ile) was significantly related with the drop of tubular sodium transport.

Adult↗
PubMed1993

31P magnetic resonance spectroscopy investigation of skeletal muscle metabolism in uraemic patients.

Using the method of in vivo magnetic resonance spectroscopy we examined 17 patients with moderately advanced chronic renal insufficiency, 21 patients with chronic renal failure treated by haemodialysis, and 15 dialyzed patients with symptomatic renal osteopathy. The ratios of intracellular phosphocreatine and inorganic phosphate concentrations of these subjects measured at rest were compared with those found in healthy controls. While we noted significantly lower (p < 0.01) ratio values in all patients, subjects with osteopathy showed a lower value than dialyzed patients free of bone disease. Haemodialysis improved the result of examination in 7 patients. The results can be summarized as follows: (1) patients with altered renal function have significantly impaired energy metabolism of skeletal muscle, and (2) the disorder is more severe in patients with renal osteopathy than in those free of it.

Adenosine Triphosphate↗
PubMed1992

[Evaluation of glomerular filtration in patients after renal transplantation and treatment with cyclosporin A].

According to some findings (Ross et al. 1987) the creatinine plasma concentration (Pcr) is an inaccurate indicator of glomerular filtration (GFR) in patients with a transplanted kidney, treated with cyclosporin A (CyA), who are in a stabilized state of renal function. In the submitted work the authors investigated whether the inaccuracy of the assessed GFR based on Pcr or creatinine clearance (Ccr) is greater than in patients with various chronic renal diseases who at the time of examination did not take any drugs. The investigation was made in 30 patients with a transplanted kidney treated with CyA as well as azathioprine and prednisone. The authors examined also 51 patients with various chronic renal diseases, mostly chronic glomerulonephritis or tubulo-interstitial nephritis. The GFR value was assessed on the basis of polyfructosan clearance (CPF). In subjects with a transplanted kidney a significant linear relationship was found between Ccr and CPF (r = 0.829, p < 0.001). A similar relationship was found in patients with chronic renal disease (r = 0.935, p < 0.001). The regression lines characterize this relationship in both groups and do not differ significantly. Between values of Pcr and CPF a significant relationship of a hyperbolic character was found in both groups (r = 0.693, p < 0.001 and r = 0.741, p < 0.001 resp.). The hyperbolic relations found in the examined groups did not differ significantly. The findings confirm that a normal or only slightly elevated Pcr value can be associated with a markedly reduced GFR, in some instances to as much as one third of the normal values.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Relation between creatinine clearance and glomerular filtration in various stages of chronic renal disease].

The relationship between creatinine clearance (Ccr) and inulin (C(in)) was investigated in 20 healthy subjects (group A) and 54 subjects with chronic renal disease (C(in): 10-80 ml/min/1.73 m2) treated conservatively (group B) and in 10 subjects with regular dialyzation treatment and a preserved residual diuresis (more than 1000 ml/24 h) (group C). In subjects from group B the Ccr/C(in) values were significantly higher than in healthy subjects (p < 0.01). In subjects of group C the values of Ccr/C(in) before dialysis did not differ significantly from values recorded in healthy subjects. Twelve hours after dialysis a marked increase of C(in)/Ccr occurred (p < 0.001). The findings are consistent with the idea that the increase of tubular creatinine secretion in patients with chronic renal disease is associated with a rise of its plasma concentration. In terminal stages in chronic renal failure there is, however, again a drop of tubular creatinine secretion which is reversible and rises after dialysis. These changes in tubular creatinine secretion could be explained by the fact that in chronic renal failure substances cumulate in the organism which inhibit tubular creatinine secretion. Due to haemodialysis the concentration of these inhibitors of creatinine secretion declines and after dialysis this process increases again temporarily. The findings suggest that the residual Ccr value assessed before dialysis is closer to the real value of glomerular filtration than values assessed during dialysis.

Adult↗
PubMed1992

Cyclosporine A treatment and evaluation of glomerular filtration rate in patients with a transplanted kidney.

According to some findings [Ross et al. 1987], the plasma concentration of creatinine (Pcr) is an inaccurate reflection of the glomerular filtration rate (GFR) in renal graft recipients with stabilized renal function, treated with cyclosporine A (CyA). In this study, we sought to determine whether the inaccuracy of GFR assessment on the basis of Pcr or creatinine clearance (Ccr) in these individuals is greater than in patients suffering from various chronic renal diseases untreated by any drugs during the examination. The study was performed in 30 renal graft recipients, treated with CyA in combination with azathioprine and prednisone. Further, 51 patients suffering from a chronic renal disease, mostly chronic glomerulonephritis or tubulointerstitial nephritis, were investigated. GFR was evaluated on the basis of polyfructosan clearance (CPF). A significant linear relation between Ccr and CPF (r = 0.829, p less than 0.001) was demonstrated in individuals with a transplanted kidney graft treated with CyA. A relationship of the same character was observed in the group of patients suffering from chronic renal diseases (r = 0.935, p less than 0.001). There is no statistically significant difference between the regression lines characterizing these relationships in both groups. A significant correlation of hyperbolic character between Pcr and CPF was found in both groups investigated (r = 0.693, p less than 0.001, and r = 0.741, p less than 0.001, respectively). The hyperbolic relationship noted in the studied groups did not differ significantly. These findings confirm a normal, or a mildly raised Pcr can be associated with a marked decrease in GFR, in some cases to a value as low as a third of the normal one.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[The critical value of residual kidney function in patients with chronic kidney failure from the viewpoint of the concentration of urea and potassium in the plasma].

Residual kidney function was examined in 10 patients with chronic renal insufficiency under balance conditions and in 30 outpatients on the basis of urea clearance (Curea) and potassium clearance (CK). Protein intake was 35-40 g/day (0.5 g/kg/day) and potassium intake was 30-40 mmol/day. Under these conditions the critical values of residual kidney function were as follows: 1) plasma urea concentration (Purea) did not exceed 30 mmol/l if Curea did not drop below 3.8 ml/min; 2) plasma potassium concentration (PK) did not exceed 5 mmol/l if CK did not decrease below 4.1 ml/min. Clinical examination of Curea and CK provides additional information to the examination of creatinine clearance (Ccr) or its plasma concentration (Pcr). Our results suggest that the critical value of residual kidney function cannot be defined only on the basis of examination of Ccr or Pcr. Examination of Curea and CK can help in the interpretation of very high Purea and hyperkalemia in patients with chronic renal insufficiency.

Ambulatory Care↗
PubMed1991

[The effect of hemodialysis on potassium excretion by residual nephrons].

In 19 patients with chronic renal failure and still preserved residual diuresis the inulin clearance (Cin) and renal potassium excretion were assessed before and 12 hours after haemodialysis (HD), combined with conventional ultrafiltration. The mean value of Cin after HD declined significantly (p less than 0.001). As a result of HD a significant decline of the plasma potassium concentration occurred (p less than 0.005) and of the urinary excretion (p less than 0.01). The mean value of the fractional potassium excretion (FEK) did not change significantly as a result of HD. The reduced urinary K excretion after HD correlated significantly (p less than 0.05) with the decline of Cin. The findings suggest that the decline of the urinary potassium excretion after HD is above all due to a decline of the glomerular filtration rate. The tubular potassium secretion does not change significantly under these conditions. These findings support indirectly the idea that the increased tubular potassium secretion in residual nephrons in patients with chronic renal failure is not conditioned by retention of low-molecular dialysable substances.

Female↗
PubMed1991

Renal amino acid excretion and aging.

The urinary excretion and serum concentration of amino acids were studied in 62 healthy individuals aged 15 to 70 years. In elderly subjects (61-70 years), it was found that renal amino acid clearance per 100 ml GFR (fractional excretion, FE) rose significantly in the following amino acids: CYS, VAL, MET, ILE and LEU. Since the serum concentrations of these amino acids showed no significant changes, but the GFR was reduced, it can be concluded that the raised FE of these amino acids was due to a decrease in their effective tubular reabsorption. A significant correlation was found between FENa and FE of most amino acids including those mentioned above. The findings support the assumption that changes in tubular Na+ transport probably participate in the changes of tubular amino acid transport in elderly individuals.

Adolescent↗
PubMed1990

[Preclinical modeling of the possible effect of acute uremia on drug resorption in the gastrointestinal tract].

The authors investigated in experiments on rats the course of serum concentrations of sulfisoxazole (S) and acetylsulfisoxazole (AS) in normal rats and in rats after bilateral nephrectomy after intra gastric administration of S. Serum concentrations of S and AS during the first three hours following administration did not differ significantly or were very close. During the subsequent hours the serum concentrations of S and AS in uraemic animals were significantly higher than in controls. The value of the absorption constant in the uraemic animals was on average higher and the absorption half-life lower than in controls. The assembled results suggest that in acute uraemia in rats the intestinal reabsorption of S and its metabolism in the liver are not reduced. The findings support the idea that the model used could be useful in preclinical research of drugs used in the treatment of acute uraemia.

Acute Disease↗
PubMed1990

[Urea clearance and measurement of glomerular filtration in patients with chronic renal insufficiency].

In 31 patients with chronic renal insufficiency (CHRI) the authors investigated the relationship between insulin or polyfructosan S (CPFS) clearance, urea clearance (Curea) and creatinine clearance (Ccr). The mean clearance values of these substances were as follows: CPFS: 0.198 (+/- 0.091) ml/s, Curea: 0.183 (+/- 0.086) ml/s, Ccr: 0.315 (+/- 0.169) ml/s. Between the values of Curea and CPFS, similarly as between values of Ccr and CPFS, a significant linear relationship was revealed, however, the regression line indicating the relationship between Curea and CPFS was closer to the identity line than the relationship between Ccr and CPFS. The results suggest that in patients with CHRI (where CPFS less than 0.4 ml/s) Curea is close to the value of glomerular filtration.

Adult↗