Objective: To investigate whether the steady decline in the maternal essential fatty acids (EFA) status during pregnancy observed in Dutch pregnant women is a local or general phenomenon. Design: The EFA status was measured during uncomplicated, singleton pregnancy of healthy women from the Netherlands, Hungary, Finland, England and Ecuador. In addition, the EFA status of their neonates were measured at birth. Fatty acid pro®les were analyzed in phospholipids isolated from maternal plasma and from umbilical plasma and cord vessel walls. Results: Considerable differences between these centers were observed in the maternal EFA levels and EFA status indexes. However, the change in the absolute as well as relative amounts of the EFAs followed a similar course in the ®ve populations during pregnancy. The neonatal EFA pro®les re¯ected the differences found in maternal plasma during pregnancy and shortly after delivery. Comparable correlations were found, particularly, between the neonatal and the maternal n 7 3 fatty acids in the participating groups. Conclusions: It seems that the reduction in maternal EFA status during pregnancy is a general phenomenon, and is largely independent of differences in dietary habits and ethnic origin. Since the lowest values for certain maternal EFAs in a given country were signi®cantly higher than the highest value of these EFAs throughout pregnancy in other countries, the functional implications of the pregnancy-associated reduction in the maternal EFA status for the fetal and neonatal development is not obvious and needs to be further elucidated.

Sex dependence of copper, zinc, iron nutritional status and hepatic lipid peroxidation was studied in gonadectomized, hormone substituted and sham-operated male and female rats. The experiment was performed on H-Wistar rats (106 +/- 10 g) fed conventional laboratory food ad libitum for 12 weeks. The estrogen dependence of copper status is fully confirmed by the results of this study. In hormonally active females the malondialdehyde production was depressed which is supposed to be connected with high copper and low triglyceride levels in the liver. The anaemia observed in estrogen substituted rats may be a result of lower lipid peroxidation rate. The levels of retinol and alkaline phosphatase activity in sera are probably influenced by estrogen action. It is suggested that testosterone leads to acceleration of lipid peroxidation.

No abstract

For measurement of the concentration of oxidised cholesterols in foodstuffs, a method was developed by adapting the well‐known enzymatic determination of cholesterol. A linear correlation was found between the absorbance measured after enzymatic reaction and the concentrations of 7α‐hydroxycholesterol, 7β‐hydroxycholesterol, 7‐ketocholesterol, cholesterol‐5α, 6α‐epoxide in the range 1–12 μg. The usefulness of this method was demonstrated by determination of the four cholesterol oxidation products separated by TLC from the non‐saponifiable lipid fraction of 5‐month‐old whole‐egg powder (stored under different conditions) and of biscuit enriched with egg powder. The main advantages of the combination of TLC and the enzymatic method, beyond its rapidity and sensitivity, are that the determination of cholesterol oxidation products can be carried out in parallel with many samples containing small amounts of oxidised cholesterols even in the presence of a large quantity of cholesterol.

The author studied the retinal changes induced by ketamine in animal experiments. Ultrastructural changes were observed in the inner segment of the photoreceptors, in the three nuclear layers, and in the nerve fiber layer following ketamine monoanesthesia of 60 min duration. A pronounced destruction of the Müller's cells nourishing the nervous elements was seen. Three days after the anesthesia, remarkable regression of the neuronal changes and extreme accumulation of glycogen in the Müller's cells occurred. These phenomena, as well as some other ophthalmological side effects, were explained with the development of relative retinal hypoxia due to the increased oxygen metabolism which was caused by the ketamine anesthesia.