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K F Michaelsen

Publications and source records attributed to K F Michaelsen.

119 records · Page 7Linked to original sources
PubMed1979

Prader-Willi syndrome and chromosomal mosaicism 46,XY/47,XY,+mar in two cases.

Two cases of the Prader-Willi syndrome with 46,XY/47,XY,+mar are reported. The majority of Prader-Willi patients with chromosome abnormalities have either 15/15 translocations or mosaicism. Both of these aberrations presumably occur after fertilization. A possible relationship between high parental age and chromosome abnormalities in the Prader-Willi syndrome is discussed.

Child↗
PubMedDate not supplied

Marginal vitamin A deficiency in pigs experimentally infected with Trichuris suis: a model for vitamin A inadequacy in children.

The development of an experimental model for marginal vitamin A deficiency in humans is of major interest, enabling the elucidation of possible interactions with helminth infections. We established a useful experimental model for human vitamin A deficiency in young pigs; deficiency was induced through a depletion method encompassing both sow and offspring. We report on a 2 x 2 study in which 18-week-old vitamin A deficient pigs and vitamin A sufficient littermates were infected with both of the intestinal nematodes Trichuris suis and Ascaris suum and followed for 14 weeks through 32 weeks of age. Forty-nine pigs were followed with respect to bodyweight, liver biopsies and blood samples for retinol concentration and faecal samples for parasite eggs and worms. Liver and serum concentrations of vitamin A were significantly diminished in the vitamin A deficient (VAD) group as compared to the vitamin A sufficient (VAS) group both before (P < 0.001) and after inoculation with T. suis and A. suum (P < 0.02). A significant correlation between retinol content in micro-biopsy needle samples and gross liver content was found (r = 0.457, n = 48, P = 0.001). The adult T. suis worms in the VAD group were marginally smaller (36.7 vs 40.2 mm; P = 0.08), more orally located (section 2.9 vs 3.9; P = 0.08) and had a higher proportion of males (0.58 vs 0.50; P = 0.08) whereas there were no effects of diet treatment on fecundity. The proportion of pigs with faecal T. suis egg excretion 12 weeks post inoculation (p.i.) was significantly lower in the VAD group compared with the VAS infected group (21 vs 78%; P = 0.036). In addition, faecal T. suis egg excretion was significantly lower in the VAD group at both week 11 (P = 0.040) and week 12 p.i. (P = 0.021). Vitamin A deficiency may have altered the functional integrity of the mucosal intestinal epithelium, disrupting the normally delicate attachment of T. suis and leading to the premature termination of infection. However, a possible antagonistic interaction, if verified, should not preclude interventions to improve vitamin A status, i.e., treatment should accompany anthelmintic treatment.

Animals↗
PubMedDate not supplied

Changes in body composition during growth in healthy school-age children.

Bone-mineral-free lean body mass (LBM) and fat mass (FM) were determined by DXA scanning in 343 healthy children and adolescents (142 males) aged 4.9-19.3 yr. The main sex difference was the earlier flattening of the LBM according to age curve for girls compared to boys and the higher increase in FM with age in girls. 332 persons (140 males) were examined again after 1 yr and accretion rates for LBM and FM were calculated. The main sex difference was a later and higher peak in LBM accretion in boys compared to girls and a nearly constant increase in FM throughout puberty in girls, while boys had no increase in FM during puberty. The differences may reflect the higher androgen production in male puberty.

Absorptiometry, Photon↗
PubMedDate not supplied

Height of conscripts in Europe: is postneonatal mortality a predictor?

The height of conscripts has increased steadily during recent decades in Europe. We have collected data on conscript height from 11 European countries to examine if this trend is continuing. In the Scandinavian countries and The Netherlands the increase in height reached a plateau during the 1980s, while the trend towards increasing adult height continued in the middle and southern European countries. There are still large differences between the countries (1990: The Netherlands 181.2 cm and Portugal 170.3 cm), with a marked trend for the tallest conscripts to be in the north and the shortest in the shortest in the south. It has been suggested that the secular increase in adult height is mainly determined by an increase in growth during the first years of life. We examined postneonatal mortality (PNM) as a proxy for adverse environmental factors, mainly poor nutrition and infections, affecting growth during infancy, and related it to conscript height in the European countries. The general pattern was a rapid decrease in PNM until a low level was reached, after which it remained low, or decreased only very slowly. In countries where the increase in conscript height has levelled off, PNM reached a low and stable level (about 3-5 per thousand) approximately two decades before this stagnation. We speculate that the increase in height will continue in the rest of the European countries until approximately two decades after PNM has reached the same low level.

Adolescent↗
PubMedDate not supplied

Infrared analysis for determining macronutrients in human milk.

Infrared (IR) analysis is widely used for routine analysis of cow milk in dairies. The aim of this study was to evaluate the precision and accuracy of an IR analyzer (Milko-scan 104) for measuring protein, fat, carbohydrate, and, indirectly, the energy content of human milk. The results of the IR analysis were compared with those of the following reference methods: protein--Kjeldahl (nitrogen minus nonprotein nitrogen); fat--Roese Gottlieb; carbohydrate--lactose enzymatic assay; energy--bomb calorimetry. The precision (repeatability coefficient of variation) of the IR results was high for all four components: protein 0.4%, fat 1.0%, carbohydrate 0.2%, and energy 0.1%. There was a close linear covariation between IR results and reference results. [Protein content was determined with an error (SD) of 0.01 g/100 ml and fat with an error of 0.03 g/100 ml.] The covariation between IR carbohydrate results and the results of the lactose assay was poor, probably because the oligosaccharides in the milk were included in the results from the IR analysis and not in the results from the lactose assay. IR analysis is a valuable method in research, especially in epidemiological surveys, in which large numbers of samples are analyzed, and for continuous monitoring of the nutritional value of human milk in milk banking programs.

Humans↗