Antioxidant status in patients with cystic fibrosis.

BACKGROUND: The aim of the study was to assess the antioxidant status in cystic fibrosis (CF) patients compared to healthy controls. In order to determine the influence of nutrition on the level of the antioxidants, nutrient intake was also monitored in both groups at the time of the antioxidant assessment. SUBJECTS AND METHODS: The authors measured the serum malondialdehyde levels in children with CF, n = 21; 9 females and 12 males, mean age: 8.71 years (6-12 years) and compared these values to the levels found in age-matched healthy control subjects, n = 24; 13 females and 11 males, mean age: 8.33 years (6-12 years). In order to assess the antioxidant status, catalase and superoxide dismutase activities in washed erythrocytes, glutathione peroxidase activity of heparinized whole blood and serum ascorbic acid, alpha-tocopherol and retinol levels were measured. Total antioxidant status (TAS) was also tested. The patients with CF received vitamin supplementation in doses prescribed in international guidelines (alpha-tocopherol: <10 years 100 mg daily, >10 years 200 mg daily, retinol: 2.5 mg daily, ascorbic acid: 100-200 mg daily). RESULTS: Plasma levels of malondialdehyde were significantly higher (p < 0.05), superoxide dismutase activities were significantly lower (p < 0.05) in patients with cystic fibrosis. There were no significant differences in catalase, glutathione peroxidase activities and TAS levels between CF patients and control group. Plasma ascorbic acid, alpha-tocopherol and retinol levels were within normal limits in both groups. CONCLUSION: On the basis of the present results this regime failed to provide sufficient antioxidant protection. Therefore, the authors suggest that the daily dose of these antioxidants should be either increased or to administer in parenteral route to patients with severe form of the disease.

[Body composition in overweight children, healthy children as well as children with mucoviscidosis, measured by multifrequency impedance]. / A testösszetétel multifrekvenciás impedanciaméréssel nyert eredményei elhízott, egészséges és mucoviscidosisos gyermekekben.

The body composition of a total of 90 children (aged 5-18) were subjected to multifrequency impedance measurement with a Human IM Scan impedance analyser. We compared data of 30 overweight children (17 boys, 13 girls; mean age 11.47 yrs, range: 4-17 yrs), 30 children with cystic fibrosis (12 boys, 18 girls; mean age 12.8 yrs, range: 3-24 yrs) and 30 healthy children (12 boys, 18 girls; mean age 13.4 yrs, range 7-18 yrs). The percentage of fat mass was found to be inversely proportional to total body water. Extracellular water expressed as a percentage of the total body water was significantly higher in overweight children than in the other two groups: (p < 0.01) between children with cystic fibrosis and overweight children, (p < 0.05) between healthy children and overweight children. Extracellular water expressed as a percentage of total body water was lower in children with cystic fibrosis than in healthy children (p < 0.05). The ratios of extracellular mass and body cell mass to body weight were significantly lower in overweight children than in healthy children (p < 0.01) or in children with cystic fibrosis (p < 0.01). The ratio of exchangeable sodium and potassium was lower in all three groups than the normal value given for adults (> 0.87), but in overweight children it was significantly higher than in the other two groups; (p < 0.01) between children with cystic fibrosis and overweight children, (p < 0.05) between healthy children and overweight children. Multifrequency impedance measurement is reliable, fast, non-invasive, easy to carry out, therefore we consider it very useful in determining the body composition of children in various pathological conditions.

Altered erythrocyte sodium-lithium counter-transport and Na+/K(+)-ATPase activity in cystic fibrosis.

Patients with cystic fibrosis (CF) exhibit normal concentrations of sodium and chloride in spite of the disturbance of Cl- and Na+ transport in epithelial cells. To characterize compensatory mechanisms in the regulation of sodium homeostasis, erythrocytes of 13 CF patients were analysed for sodium-lithium counter-transport (SLC), Na+/K(+)-ATPase activity and intracellular sodium content. Values were compared to those of healthy controls. Patients with CF had normal serum sodium and chloride concentrations and renal excretions of these ions were within the physiological range. Intracellular sodium concentration was similar in the CF and the control group (6.8 +/- 2.2 vs 5.7 +/- 1.0 mmol/l RBCs). Red blood cells' SLC and Na+/ K(+)-ATPase activity were elevated in CF patients (381 +/- 106 mumol/h/l RBCs vs 281 +/- 64; p < 0.01) and (445 +/- 129 mumol ATP mg prot/h vs 322 +/- 84, p < 0.01). Our study demonstrates that transmembrane cation transport systems are highly activated in CF. The increased sodium transport may be part of a compensatory mechanism of sodium homeostasis in children with CF.

[Analysis of five mutations of cystic fibrosis occurring in the Hungarian population]. / A cisztás fibrózis öt mutációjának vizsgálata a magyar populációban.

The authors screened 374 patients clinically diagnosed be affected by cystic fibrosis. Mutations delta F508, G542X, G551D, R553X, N1303K were analysed to obtain genetic diagnosis. The large number of patients involved in this study allowed for authors to present precise data of the frequencies of these mutations in Hungary. The frequency of mutation delta F508 is found to be significantly less then the numbers reported in other studies. This is due to sampling bias occurring at little sample sizes. Mutational analysis has been used as a tool of prenatal diagnosis.

[Detection of delta F508 mutation in cystic fibrosis]. / A delta F508 mutáció kimutatása cystikus fibrosisban.

The common major mutation (delta F508) resulting in the removal of a phenylalanine residue of the cystic fibrosis gene product has been identified in patients with cystic fibrosis in several European countries. The frequency of this mutation was analyzed in 39 Hungarian patients with cystic fibrosis and in some of their relatives. In 43 out of the total 65 persons involved in the study (66.15%), and in 50% of cystic fibrosis chromosomes the delta F508 mutation could be detected. 56.4% of the patients were homozygous for the mutation. The frequency of the delta F508 mutation in these Hungarian patients resembles the values found in Middle Europe. Pulmonary and enteral symptoms were more severe in cystic fibrosis patients with delta F508 mutation. Although the number of patients is relatively low, missing or mild lung involvement characterized the cases with non-delta F508 mutation.