Activin receptor expression and induction of apoptosis in rat blastocysts in vitro.

BACKGROUND: Apoptosis, a process of normal embryonic development, is enhanced in blastocyst from diabetic rats. Nevertheless, glucose seems not to be the only factor involved. Activin A, a TGF-beta family member, is also increased in maternal serum from diabetic pregnancy. METHODS: Flushing medium, blastocysts and uterine cells were obtained from 5 day old pregnant rats. The presence of activin A in flushing medium was investigated by western blotting. RT-PCR was used to test for the presence of activin betaA subunit mRNA in cultured uterine cells. Blastocysts were stained by immunohistochemistry for activin receptor types IIA and IIB, and chromatin degradation (apoptosis) was investigated by terminal transferase-mediated dUTP nick end labelling in blastocysts exposed in vitro to activin. RESULTS: In this study, we demonstrate the presence of activin A protein in fluid from rat uterine horns at day 5 of pregnancy, as well as the presence of activin A receptors type IIB in the trophectoderm and inner cell mass and activin A receptor type IIA in trophectoderm cells only. Activin A increases the chromatin degradation level in vitro. CONCLUSIONS: Activin A protein was found in fluid from uterine horns, and mRNA expression of betaA activin subunit in cultured uterine cells suggests probable secretion from decidual cells. Moreover, activin A increases specifically the apoptosis level in rat blastocyst in vitro.

Accuracy of magnetic resonance imaging for measuring fetal sheep lungs and other organs.

OBJECTIVE: Lung volume measurement by fetal magnetic resonance imaging (fetMRI) has been used to predict survival of fetuses with isolated congenital diaphragmatic hernia (CDH). So far, the accuracy and precision of fetMRI for volumetry of either the normal or hypoplastic developing lung has not been formally studied. METHODS: A total of nine sheep carrying 14 fetuses underwent fetMRI under general anesthesia at a mean of 118 days' gestational age (term = 145 days). A total of 61 organs were measured in nine normal fetal sheep and five that underwent surgical creation of diaphragmatic hernia (DH), so as to induce pulmonary hypoplasia. Lungs were measured on T2-WI (weighted images) in three different planes, while liver and kidneys were measured in the axial (T1-WI) and sagittal (T2-WI) planes, respectively. Necropsy was done within 24 h after fetMRI to determine the volume postmortem by the water displacement method. Values were linearly correlated and a Bland and Altman analysis was done for volume measurement comparison, calculating means +/- SD, bias (mean of the difference of volume measurements), precision (SD of the difference) and absolute and proportionate limits of agreement for both methods. The accuracy of fetMRI volume measurement was determined for different organ groups by calculating the median relative error and precision index, both being measures of error in proportion to the magnitude of the volume measured, as a clinically relevant proxy of potential errors. RESULTS: The fetMRI volume measurements were on average larger than postmortem volumes, except for the kidneys. Kidney volume determination had a relative error of 29%, while measurements of larger organs had larger relative errors (42% for liver). Normal lungs were less accurately measured in the coronal or sagittal than in the axial plane (relative error 53%, 73% and 38%, respectively; P < 0.05 for sagittal vs. axial). Axially-measured lung volumes were more accurate for lungs of normal sheep compared to DH lungs (relative error 38% vs. 73%, respectively; P < 0.05). CONCLUSION: FetMRI measured systematically higher volumes for organs such as fetal liver or lung. This may be related to fluid loss or lack of perfusion at the time of necropsy. Measurement of lung volume by fetMRI was most accurate in the axial plane. Measurements of lung and liver volumes by fetMRI in normal sheep were both in agreement with volumes measured at necropsy. Loss of accuracy for DH-lungs in comparison with the accuracy when measuring other similarly small organs, such as kidneys, suggests that fetMRI measurements can be less accurate for hypoplastic lungs related to CDH. With improving hardware, it might become easier to render the fetal lung and determine its volume reliably.

Conservative management of triplet pregnancy after delivery of one foetus.

This paper intends to demonstrate that the conservative management of triplet pregnancy after delivery of one foetus is a feasible and reasonable approach. Three cases of triplet pregnancy with successful conservative management after miscarriage of one foetus, are presented and compared with cases in the literature. The route of delivery, as well as the role of tocolysis, cerclage, prophylactic antibiotic therapy and corticosteroids are discussed. Guidelines for conservative treatment are proposed. The deliveries of our three pregnancies were delayed by 63, 44 and 22 days respectively. Foetal and neonatal evolution are normal in five of the remaining foetuses. Only one intrauterine death is observed. No maternal complications with sequelae are reported. After abortion of the first triplet, contractions often persist and the birth of the two remaining foetuses may be unavoidable. Nevertheless, in our experience, confirmed by some reports in the literature, prolongation of the pregnancy after expulsion of the first foetus is possible. It can be achieved by cervical cerclage associated with tocolytic and antibiotic therapy. This management is not associated with significantly increased foetal-maternal morbidity.