Iron and folate status of pregnant black women in Gazankulu.

A limited nutritional survey was carried out in 229 first attenders at an antenatal clinic in Gazankulu during the winter of 1984. Haemoglobin concentrations equal to or less than 11 g/dl were found in 33% of these women, the prime reason being folate deficiency. Serum folate concentrations were less than a 3.5 ng/ml in 60% of subjects and less than 3.0 ng/ml in 48%. A mean corpuscular volume of 100 fl or more, which reflects a defect in red cell DNA synthesis, was present in 35%. Iron related measurements indicated that only 17% were also iron deficient but the figure is certainly an underestimate, since the presence of folate deficiency tends to mask concomitant iron deficiency. The findings underline the need for folate and iron supplementation in pregnancy; the very high prevalence of significant folate deficiency also indicates that serious consideration should be given to the fortification of maize meal with folic acid.

Cellular pharmocodynamics of several anthrocycline antibiotics.

Alterations in the C-9 side chain of the anthracycline antibiotics, adriamycin and daunorubicin, have a profound effect on antibiotic uptake and accumulation by cultured L1210 cells. The degree of inhibition of DNA and RNA biosynthesis in the L1210 cells is directly related to the cellular uptake and accumulation of the drug analogues. Polar drug metabolites, daunorubicinol and adriamycinol, retain inhibitory activity against nucleic acid metabolism but have a decreased membrane binding and permeability. Cellular uptake and accumulation of the C-9 analogues are inversely related to drug polarity. We propose that the polarity of the anthracycline analogues contributes heavily to the differences in therapeutic index and in vivo activity through fundamental effects on membrane permeability, metabolism, and macromolecular binding.

Oxygen equilibrium of hemoglobin E.

Oxygen equilibrium was determined on hemoglobin of individuals both heterozygous and homozygous for hemoglobin E. The whole blood oxyhemoglobin dissociation curve of AE blood was identical to that of normal AA blood. E hemoglobin, isolated by diethylaminoethyl Sephadex and carboxymethyl cellulose column chromatography, had oxygen affinity, heme-heme interaction, and Bohr effect identical to those of hemoglobin A prepared from the same column. Furthermore, the two hemoglobins had equal reactivity with 2,3-diphosphoglycerate. Phosphate-free hemolysates of blood from E and A homozygotes also had identical oxygen saturation curves. These results do not confirm earlier reports that hemoglobin E has an abnormally low oxygen affinity.

Studies of paroxysmal nocturnal hemoglobinuria erythrocytes: increased lysis and lipid peroxide formation by hydrogen peroxide.

When paroxysmal nocturnal hemoglobinuria (PNH) erythrocytes were exposed to H(2)O(2) they lysed excessively and formed greater than normal quantities of lipid peroxides when compared to red cells of normal subjects and patients with most types of hematologic disease. It was also shown that lytic sensitivity to acidified serum was related to the enhanced lytic sensitivity to H(2)O(2). If the lipid of PNH cells was first extracted then exposed to ultraviolet radiation more lipid peroxides were formed than in extracts of normal red blood cells. The possible explanations for these findings and their relationship to the PNH hemolytic mechanism are discussed.