No abstract

No abstract

No abstract

Summary. Three groups of women were delivered by caesarean section before labour: for an abnormal fetal heart rate (FHR) trace (21 cases, group 1), or for maternal deterioration in severe pre‐eclampsia without gross fetal heart rate abnormalities (20 cases, group 2), or to avoid mechanical difficulties in labour at term (30 cases, group 3). The mean gestational ages of the first two groups were 32 weeks with a high proportion of infants small‐for‐gestational‐age. In group 1, FHR variation (mean range of pulse intervals) was less than half (20·6 SE 1·2 ms) of the normal value at the same age (44·4 SE 1·5 ms). This was associated with hypoxaemia (mean umbilical artery Po2 of 6 mmHg at delivery), with evidence of compensation shown by an elevated amniotic fluid erythropoietin. The fetuses were hypoglycaemic and had greater umbilical artery blood alanine concentrations, but no large changes in adenine nucleotide or endorphin plasma concentrations. Although there was a minor degree of respiratory acidaemia at birth, there was not significant metabolic acidaemia. The results demonstrate that the reduced variation of ‘suboptimal’ and ‘decelerative’ fetal heart rate records is associated with fetal hypoxaemia and evidence of nutritional deprivation, but not with asphyxia.

1. After decreasing muscle ATP by a 2 min period of intense exercise, we have studied purine metabolism by using high-pressure liquid chromatography. 2. A major increase in hypoxanthine concentration in plasma and urine was found with increases in xanthine and, in plasma, inosine. Erythrocyte hypoxanthine rose with the level in plasma, but there was no corresponding rise in IMP, the first intracellular metabolite of hypoxanthine. No rises in uridine or urate were found in plasma. 3. Plasma adenosine did not rise and fall significantly after exercise, but a small rise and fall in adenine nucleotide concentrations in plasma was found. 4. Running, swimming and games, which tended to be at the weekend, were associated with a rise in hypoxanthine and xanthine excretion; exercise was probably the cause of the higher excretion during the day than at night. Such activities do not produce changes in concentrations of ATP in muscle, although turnover must rise. 5. The results are consistent with widespread purine exchange between tissues and a 'circulating hypoxanthine pool'.

Forty‐two infants (20 males, 22 females) with classical phenylketonuria (PKU) entered a prospective, double‐blind, randomized study to investigate the effects on biochemical and physiological outcomes of a phenylalanine‐free infant formula containing a fat blend supplemented with the long‐chain polyunsaturated fatty acids (LC‐PUFA), docosahexaenoic acid (DHA, C22:6n‐3), and arachidonic acid (AA, C20:4n‐6). Between entry and 20 weeks (entry and 1y) of age, median DHA levels in erythrocyte membrane phospholipids decreased by 15% (22%) in the LC‐PUFA supplemented group (n=21) and by 61% (64%) in the control group (p<0.001; n=18). A dietary supply of LC‐PUFA in infants with PKU prevents the decline in DHA levels associated with a diet supplying minimal sources of LC‐PUFA. DHA status in turn, independent of diet, may influence the maturation of the visual system in infants with PKU.

SUMMARY A survey has been made of the steroids in cows' milk using a method for the group analysis of steroids. Serial studies during and after pregnancy showed changes in progesterone concentration consistent with known variations in plasma concentrations. More progesterone was obtained from samples taken at the later stages of milking and samples obtained in the evening generally contained more progesterone than morning samples. Steroids were concentrated in the cream. Relatively constant levels of 5α-androstane-3,17-dione were found and it is suggested that this steroid is of adrenal origin. The predominance of 5α steroids in milk suggests that these are derived, at least in part, from metabolism in the mammary gland. The possible use of these findings in diagnosis of pregnancy and in studies of the hormonal control of lactogenesis is indicated.

No abstract