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K Dörner

Publications and source records attributed to K Dörner.

At least 37 records · Page 2Linked to original sources

Urinary zinc excretion in infancy.

In view of the conflicting data on urinary Zn excretion in infancy we investigated the possible influence of contamination, collecting methods, nutrition (human milk versus formula) and longitudinal changes during the first 16 weeks of life. Methodical investigation showed that special attention is necessary to avoid contamination due to the use of Zn-containing baby creams in the genital region. The sampling device for collection should include the smallest area of skin possible and the use of Zn-containing baby creams has to be avoided both during the collection and at least 24 hours prior to urine collection. Previous fractional urine sampling of the collecting method to be evaluated proves that erroneously high values are not obtained at the beginning of collection. Midstream urinary samples reduce the possibility of contamination. Increased urinary excretion was shown in pre-term infants under theophylline or coffeine medication. The median daily urinary Zn excretion in healthy breast-fed term infants declined significantly from 0.063 (0.027-0.111) mg per kg body weight at the age of 2 weeks to 0.018 (0.004-0.059) mg per kg body weight at the age of 16 weeks. Comparable values for formula-fed term infants were 0.029 (0.025-0.063) mg per kg body weight initially and 0.025 (0.007-0.059) mg per kg body weight at the end of the study. These values can be used as reference values for the urinary Zn excretion of healthy infants.

Aging↗

Selenium balances in young infants fed on breast milk and adapted cow's milk formula.

Selenium intake, renal and fecal excretion, and retention were determined in 11 breast-fed term infants and in 9 term infants fed with an adapted cow's milk formula. In most cases three-day-balances were determined five times at the age of 2, 5, 8, 12, and 16 weeks. Analytical determination of selenium was by atomic absorption spectroscopy with a selenium hybrid system after wet ashing of samples. The mean breast milk concentrations of selenium show a significant decrease in the course of lactation from 31.0 micrograms/L in the first collecting period to 17.6 micrograms/L in the last one. The two formula milks contained 11.8 and 7.7 micrograms/L. Intake in the breast milk group was higher than in the formula group, whereas absolute renal and fecal excretion were essentially the same. This leads to a higher selenium retention in the breast-fed infants than in the formula-fed infants, where most of the balances are negative.

Adult↗

Longitudinal manganese and copper balances in young infants and preterm infants fed on breast-milk and adapted cow's milk formulas.

1. Mn and Cu intake and retention in twenty full-term infants and six preterm infants were studied on the basis of 72 h balances. The age of the infants was 2-16 weeks and the gestational age of the preterm infants (triplets) 34 and 36 weeks. Three nutrition schemes were pursued: breast-fed, formula-fed with unsupplemented adapted formula and formula-fed with trace element supplementation. 2. The mean Mn concentration of all breast-milk samples (n 2339) was 6.2 micrograms/l. The two formulas had similar Mn concentrations (77 and 99 micrograms/l) but had different Fe, Cu (121 and 619 micrograms/l), Zn and I contents. The mean Cu concentration in mother's milk was 833 micrograms/l. 3. The following mean daily Mn intakes and retentions (micrograms/kg) respectively were measured: breast-fed full-term 1.06 (SD 0.43) and 0.43 (SD 0.65), formula-fed full-term 14.2 (SD 3.1) and 2.8 (SD 4.8), formula-fed preterm 15.0 (SD 2.2) and 0.06 (SD 5.87). The results for Cu were 114.5 (SD 22.3) and 88.0 (SD 46.5) micrograms/kg in breast-fed, 19.8 (SD 4.2) and 4.6 (-11.5-9.6) in the unsupplemented formula-fed and 106.4 (SD 18.9) and 55.5 (SD 20.3) in the supplemented formula full-term infant group. No significant influence of the trace element contents of the formulas on the relative retention of Mn or Cu was found. 4. Young preterm infants, and to some degree young full-term infants, often had negative Mn balances caused by a high faecal excretion. The formulas with a Mn concentration below 100 micrograms/l gave a sufficient supply of Mn. Preterm infants fed on the unsupplemented formula had a marginal Cu supply and their first balances were negative (-3.8 (SD 1.8) micrograms/kg). 5. In accordance with the estimated safe and adequate daily dietary intakes (recommended dietary allowances), formula-fed infants receive much more Mn than breast-fed infants and their absolute retention is higher. 6. Cu from breast-milk had a significantly better biological availability than that from cow's milk formula. If retentions similar to those in breast-fed infants are intended, we conclude, therefore, that cow's milk formula should be fortified with Cu up to a level of at least 600 micrograms/l.

Animals↗

Trace elements in excavated human hair.

Concentrations of the elements Ca, Sr, Mg, Zn and Cu were determined in excavated hair specimens and adherent, most probably soil remains from two sites in Germany. Though soil contamination obviously has occurred, the two groups could be distinguished by differential trace element contents in the hair samples. The trace element concentrations might be interpreted in terms of nutritional intake, the results being corroborated by preceding bone analyses and the different local and social settings. Hair decomposition is discussed.

Calcium↗

Iron balances in infant nutrition.

Iron balance studies were performed in 17 full term male infants from their 3rd until their 17th week of life. The balance studies were made in the infant's home and comprised 5 periods with an interval of 3-4 weeks, each consisting of three 24-hour collections. Ten infants were breast-fed, 3 received an adapted infant formula (P1, iron content 1.1 mg/l) and 4 were given the same formula enriched with iron, copper and zinc (P2, iron content 10.35 mg/l). From the 3rd to the 17th week of life the breast-fed infants got a mean iron intake of 0.2 mg/kg body weight X 3 days and they retained 0.09 mg/kg b.w. X 3 days. The P1 group received 0.48 and 0.47 mg/kg b.w. X 3 days and retained -0.01 and -0.5 mg iron/kg b.w. X 3 days, while the P2 group had an intake from 5.04 to 6.38 mg b.w. X 3 days and retained between 1.13 and 3.66 mg iron/kg b.w. X 3 days. Comparing the 3 groups it can be concluded that the P1 group retained definitely less iron than the breast-fed group, whereas the P2 group retained 12 to 40 times more iron than the breast-fed babies.

Breast Feeding↗

Cholesterol fractions and triglycerides in children and adults with Down's syndrome.

In 186 patients with Down's syndrome (age 1-68 yr) total cholesterol and triglycerides were determined, quantitative lipoprotein electrophoresis was performed and cholesterol fractions and beta/alpha-lipoprotein ratios were calculated. A reference group of 51 non-mongoloid mentally handicapped adults living in the same institutions were examined in the same way. Patients' total cholesterol, beta-cholesterol and triglycerides did not differ from the controls. However, alpha-cholesterol was significantly lower and the beta/alpha-lipoprotein ratio significantly higher in patients, findings which are associated in the general population with a high risk for premature atherosclerosis. Interestingly, mortality causes and pathological findings in Down's syndrome show no increased frequency of cardiovascular diseases.

Adolescent↗

Further evaluation of the SG test strip for estimation of urinary osmolality.

The mass densities of 2000 urines from children and 2000 urines from adults were determined with the new test strip, Multistix SG, and the results were compared with osmolality measurements. Normal urinary parameters were investigated for possible interference with the test strip reading. Variations in the pH and ionic composition of urine considerably influenced the test strip reading, whereas nonionic compounds, such as glucose and urea, showed practically no interference. For patients on a normal diet and without metabolic diseases, the new test strip is more appropriate than urometry for the determination of the mass density of the urine.

Adult↗

Calculation factors and reference values for quantitative lipoprotein electrophoresis in childhood.

Agarose gel electrophoresis of lipoproteins combined with quantitative densitometry (Lipidophor) and total cholesterol determination enables the calculation of alpha-, pre-beta-and beta cholesterol. This method is quick, precise and requires less than 100 microliters serum. The calculation factors originally derived from adults were re-evaluated and corrected for children. This was achieved by iterative calculation of the results obtained by quantitative densitometry and by enzymatic determination of the cholesterol contents in electrophoretically separated lipoprotein bands. Thus, calculation factors for children were obtained, which were used for the evaluation of reference values for alpha-, pre-beta- and beta-cholesterol and for the beta/alpha-lipoprotein ratio based on a reference group of 575 healthy children of 5-18 years of age.

Adolescent↗

[Vitamin and zinc levels in leukemic children during induction therapy (author's transl)].

In 23 leukemic patients treated according to the West Berlin-protocol, we studied prospectively the plasma levels of the vitamins A (and carotinoids), B1, B2, B6, C, and E, as well as serum zinc values. Blood was drawn on days 0 (before treatment), 15, 29, and 57 of induction therapy. With one exception, plasma vitamin levels did not change significantly during treatment; however, vitamin A increased in the first and decreased in the second phase of induction (p less than 0.01) without clinical signs or symptoms. The serum levels of zinc (p less than 0.05) and the alkaline phosphatase fell continuously from day 0 to 29, but there was no correlation between these two parameters in the same patient. Clinical symptoms of zinc deficiency were not observed. We conclude: 1) That plasma vitamin levels in this limited population are generally unaffected by the underlying malignant disease, the aggressive therapy and altered feeding behaviour, and 2) that the significant decrease of serum zinc does not play a major role in the expression of clinical and biochemical side effects of cytotoxic therapy.

Adolescent↗

Increased nucleotide catabolism after cerebral convulsions.

Cardiazol induced seizures in rabbits showed that the highest oxypurine concentrations can be detected in the CSF 1 hour after the convulsions. There is a sharp decline continuing until the third hour. After that the CSF values remain nearly constant until the 24th hour being about ten times higher than in the controls. There is a good correlation of these results obtained through the densitometric thin-layer, enzymatic-oxymetric, and HPLC-methods. Creatinine and potassium were raised only during the first two hours postconvulsively. Uracil appeared in the CSF slightly higher at the 1 hour and at the 12 and 24 hour values. A parallel increase of the oxypurine and creatinine concentrations was found in the serum between 30 to 120 minutes postconvulsively. After that the raised serum values decreased slowly to the initial values. CSF samples were examined in 31 children postconvulsively: Hypoxanthine was found to be raised in 8 of 12 patients with severe grand mal seizures, 1 of 6 patients with hypsarrhythmia, 1 of 8 patients with short seizures (less than 2 min) and in all 5 patients with petit mal status. In contrast to these groups the hypoxanthine concentrations was raised only in 2 of 20 children with aseptic meningitis. The difference between the group of children with convulsions and the group of children with aseptic meningitis is significant (p less than 0.005). Also, the frequency of raised uric acid concentration is higher in the group of children with convulsions (70%) than in the group of children with aseptic meningitis (40%); (p less than 0.05).

Animals↗