Hypoxia-induced free iron release in the red cells of newborn infants.

Heparinized blood samples were obtained at birth from 164 newborn infants (101 full term; 63 preterm). Intra-erythrocyte free iron concentration and hypoxanthine plasma levels were determined by high-pressure liquid chromatography. Intra-erythrocyte free iron concentration was higher in preterm than in full term babies (p < 0.

Effects of estradiol and medroxyprogesterone-acetate treatment on erythrocyte antioxidant enzyme activities and malondialdehyde plasma levels in amenorrhoic women.

Plasma levels of 17 beta-estradiol (E2) and malondialdehyde and erythrocyte antioxidant enzyme [superoxide dismutase, catalase, and glutathione-peroxidase (GSH-Px)] activities were evaluated in 20 healthy eumenorrhoic women (EW) on day 7 of the menstrual cycle and in 48 secondary hypothalamic amenorrhea patients (AP) (time 0). The AP were randomly divided into four subgroups of 12 subjects and treated with transdermal E2 for 30 days (subgroup A), oral medroxyprogesterone-acetate for 30 days (subgroup B), and transdermal E2 plus medroxyprogesterone-acetate for 30 days (subgroup C). The fourth subgroup acted as control.

Changes in the erythrocyte antioxidant enzyme system during transdermal estradiol therapy for secondary amenorrhea.

Twenty-two hypothalamic amenorrheic patients, who were non-smokers and of normal weight, received replacement therapy for 1 month with transdermal patches containing 8 mg estradiol. No other drugs were prescribed or taken during the study. Before treatment (time 0) and 1 month after its start, blood samples were taken for assay of plasma estradiol levels, the erythrocyte antioxidant enzyme activities of superoxide dismutase, catalase, glutathione peroxidase (GSH-Px), and an age-dependent erythrocyte enzyme activity, pyruvate kinase.

Determination of red blood cell superoxide dismutase and glutathione peroxidase in newborns in relation to neonatal hemolysis.

Superoxide dismutase and glutathione peroxidase activities have been determined in newborns. Their mean values are approximately the same as in normal adults. In some cases a low content of superoxide dismutase and/or a high (superoxide dismutase/glutathione peroxidase) ratio are associated with hematological symptoms.