Screening test for preeclampsia through assessment of uteroplacental blood flow and biochemical markers of oxidative stress and endothelial dysfunction.

OBJECTIVE: This study was undertaken to evaluate whether screening through a uterine artery (UtA) Doppler and biochemical markers of oxidative stress and endothelial dysfunction predict preeclampsia. STUDY DESIGN: UtA Doppler was performed at 11 to 14 and 22 to 25 weeks on 1447 asymptomatic pregnant women. Oxidative stress, endothelial dysfunction, and antiangiogenic state were assessed in women who later developed preeclampsia and normotensive controls. RESULTS: There was a significantly increased of UtA pulsatility index (PI), plasma levels of soluble fms-like tyrosine kinase 1 (sFlt1), PAI-1/PAI-2 ratio, and F-2 isoprostane in women who subsequently developed preeclampsia compared with control pregnancies. Multivariate logistic regression showed that increased UtA PI performed at 23 weeks was the best predictor for preeclampsia. CONCLUSION: This study demonstrates early changes in markers of impaired placentation, antiangiogenic state, oxidative stress, and endothelial dysfunction suggesting that these derangements may play a role in the pathogenesis of preeclampsia. Our data point to UtA as the best test to predict preeclampsia at 23 weeks of gestation.

Renal effects of experimental obstructive jaundice: morphological and functional assessment

Background. The pathophysiology of renal impairments occurring in obstructive jaundice has been extensively studied, but underlying mechanism of these derangements remains unclear. The aim of the present study was to investigate the time-related morphological and functional changes occurring in the kidneys of rats undergoing obstructive jaundice. Methods. Histological examination, renal function assessment and determination of (Na + K)-ATPase activity were performed in the kidneys of rats 7, 14, and 21 days following bile duct ligation (BDL) or sham operation (sham). Results. Glomerular filtration rate was unaffected by BDL throughout the period of the study. Tubular effects occurred at days 7 ant 14, being more marked at day 7, and consisted of an increase of about twice in the fractional excretion of sodium and chloride, paralleled by a decreased proximal and distal tubular reabsorption of sodium of about 50 and 40 percent, respectively. Natriuresis was consistent with augmentation of osmolar clearance but it was not associated with changes in the acivity of renal (Na+ + K+)-ATPase. The ability to dilute urine was imparied at days 14 and 21 after BDL. Additionally, these effects were accompanied by decreased tubulointerstitial fibrosis and vasodilation of inner medullary capillaries. At day 21, the parameters of tubular function in BDL and sham groups were not significantly different. Conclusions. These data support the view that rasied natriuresis taking place in the initial 2 weeks following BDL is due mainly to tubular effects. The contribution of hemodynamic, paracrine and humoral mediators is discussed