A. L. Tranquilli

Doppler ultrasound was used to study the main uterine artery flow velocity waveforms in an unselected population of 272 primiparous women at 22 weeks' gestation. The incidences of subsequent complications were as follows: gestational hypertension alone, 4.4%; intrauterine fetal growth retardation alone, 4%; and gestational hypertension with intrauterine growth retardation, 3.6%. The flow velocity waveform was considered abnormal when the resistance index in the uterine artery was greater than 0.58. This identified 9.5% of the population as 'at risk' and predicted either of the above outcomes with an overall sensitivity of 74% (kappa index, 0.72). The sensitivity of prediction for gestational hypertension alone was 50% while for proteinuric gestational hypertension it was 88%. The best result was obtained for the prediction of pregnancies affected by both gestational hypertension and intrauterine growth retardation, where the sensitivity was 100%.

OBJECTIVE: To assess lipid composition, lipid peroxidation, and fluidity of the membrane of platelets from preeclamptic women. METHODS: We studied 40 primigravid women at 28-32 weeks' gestation; 20 were preeclamptic and 20 were normotensive. After preparing platelet membranes, we extracted lipids, measured cholesterol and phospholipid concentrations, and calculated the proportion of unsaturated to saturated fatty acids. Lipid peroxides expressed as conjugated dienes were determined by spectrophotometry. Membrane fluidity was determined by means of fluorescent lipophilic probes. Statistical analysis was performed by the Student t test, with significance at P < .05. RESULTS: Cholesterol concentration, cholesterol-to-phospholipid ratio, the amount of unsaturated fatty acids, conjugated dienes, and membrane fluidity significantly increased in platelets from preeclamptic patients as compared with the normotensive women. CONCLUSIONS: The discrepancy between cholesterol increase and membrane fluidity increase is consistent with the increase in unsaturated fatty acid content. In the platelet membrane, unsaturated fatty acids constitute the larger substrate for lipid oxidation and can also take part in the formation of thromboxane. Therefore, platelet membrane damage in preeclampsia, through imbalance of thromboxane A2/prostacyclin production, may contribute to the onset or maintenance of vasoconstriction and hypertension.

We have evaluated the effects of the different components of hormone replacement therapy (HRT) on the production of free radicals in platelet membranes from menopausal women. The study included 12 women in menopause for at least 6 months to a maximum of 4 years. First, the effect was determined of progestin only during the administration of 20 mg/day medroxyprogesterone acetate for 5 days. The peroxide production level was measured on day 0 and day 5. The second set of experiments was carried out in the first month of cyclic HRT with transdermal estradiol 50 micrograms/day from day 1 to day 25 and medroxy-progesterone acetate from day 13 to day 25. In this experiment, the peroxide level was evaluated on days 0, 12 and 25. A significant reduction of peroxide level was observed after oral medroxyprogesterone acetate administration. During HRT, we observed a similar reduction in lipid oxidation at the peak of the estrogen effect, and a further decrease with the administration of medroxyprogesterone acetate. It is concluded that reduction of lipid peroxidation during HRT is not only due to estrogens, but also depends upon the combined action of sex steroids. This observation justifies not only the combined regimen (estrogens plus progestin) in HRT, but also the positive effects of progestins alone on patients who cannot use estrogens.

OBJECTIVES: We have investigated foetal mesenchymal stem cells (MSCs) obtained from first-trimester chorionic villi (CV) and second-trimester amniotic fluid (AF), comparing them to adult bone marrow-derived MSCs. MATERIALS AND METHODS: We report on cell population growth in human allogeneic serum (HS) and platelet lysate (PL), immunophenotype, cytokine expression profile and immunoregulatory activity, of these foetal MSCs on stimulated peripheral blood mononuclear and lymphocyte subpopulations. RESULTS: Chorionic villi cells grow rapidly in HS, with 20 populations doublings (PDs) after 59 days (six passages), and also in animal serum, with 27 PDs after 65 days (seven passages). PL allowed for expansion in 60% of the samples tested, although it was lower than in HS. HS supported an average of 40 PDs of expansion in 20% of AF cells after 90 days, whereas animal serum supported 28.5 PDs in 66 days. CV and AF cells inhibited proliferation of stimulated T lymphocytes, suppressing population growth of both CD4+ and CD8+ T subpopulations and sometimes also, CD19+ cells. CONCLUSIONS: Our results indicate that CV would be an optimal source of MSCs with high expansion potential in a HS propagation system and immunoregulatory capacity of T and B lymphocytes. More than 90% of CV samples achieved large-scale expansion in HS, which is encouraging for potential clinical applications of these cells.