PubMed Health⌕ Search

Biomedical subjects

F Puissant

Publications and source records attributed to F Puissant.

26 records · Page 2Linked to original sources
PubMed1984

Effects of in-vitro fertilization, culture, freezing and transfer on the ability of mouse embryos to implant and survive.

The survival after transfer of frozen-thawed mouse blastocysts obtained from culture of in-vitro fertilized oocytes or 1- and 2-cell ova was compared. About 10% of transferred embryos developed to term in each group and there was no difference between embryos fertilized in vitro or in vivo. In addition to embryonic loss due to transfer, in-vitro cultivation and freezing reduced the proportion of fetuses considered viable at Day 15 of pregnancy (29.8 versus 50.7% and 26.3 versus 50.7% respectively). When used together these procedures had an additive effect on fetal wastage (18.4 versus 50.7%). In-vitro culture also entailed a significant increase of resorbing implantation sites (10.2 versus 4.3%). The re-expansion rate after freezing and thawing of blastocysts grown in vitro was paradoxically greater than that of blastocysts grown in vivo (85.8 versus 54.6%).

Animals↗
PubMed1982

A reappraisal of perinatal mortality factors in twins.

During the last 33 years, the perinatal mortality of twins has decreased regularly in our department. When examined by duration of pregnancy, mortality was lowest at 37-38 weeks. Below 38 weeks, fetal loss was paradoxically higher in twins born from multiparae. When delivery occurred beyond 38 weeks, mortality rates were increased, but only differences for primiparous group showed statistical significance. Near-term fetal loss was predominantly due to antepartal intrauterine deaths. Analysis of individual cases indicated that early termination of pregnancy might help prevent near-term stillbirths in twins delivered by primiparae. Efforts should be directed at specific detection of twins threatened by antepartum death.

Female↗
PubMed1982

Induction of implantation in the rat by intraparametrial injection of uterine RNA from oestrogen-treated animals.

Crude RNA preparations from uteri of oestradiol-treated rats induced the implantation of delayed blastocysts when injected into the parametrium of ovariectomized pregnant rats. Treatment of donor animals with labelled oestradiol showed that this effect could not be due to contamination of the RNA extracts by oestradiol. RNase digestion of these extracts suppressed their capacity to induce implantation. Purified poly (A)-rich RNA from oestrogen-treated uteri failed to elicit implantation although it was capable of increasing epithelial height when repeatedly injected into uterine horns of ovariectomized rats. These results suggest that uterine RNA synthesis might somehow mediate the effects of oestrogen in causing implantation and that RNAs other than messenger RNA might be involved.

Animals↗
PubMedDate not supplied

Morphological aspects of the placenta in HIV pregnancies.

Forty-nine placentae from HIV-seropositive mothers were collected in various hospitals in France and Belgium. Twenty [corrected] placentae with seven fetuses from interrupted pregnancies and 29 [corrected] placentae from spontaneous deliveries, including two stillborns and a set of twins, were studied morphologically. No significant abnormalities were observed in the aborted material. The placentae corresponding to deliveries presented no significant gross abnormalities but the ratio of fetal to placental weight was significantly decreased in the study group compared with the control group (6.13 versus 7.41; P less than 0.001), associated with a congestive and mature aspect of the parenchyma. Histologically a high incidence of chorioamnionitis (43 per cent) was found, contrasting with the absence of villitis. A relative villous hypercellularity was observed in the study group compared with the control group. Ultrastructural studies of 13 placentae corresponding to gestations of 10 to 40 weeks are presented. In six cases, retrovirus-like particles were found at various sites, such as villous fibroblasts, syncytiotrophoblast and endothelial cells, and in the free membranes.

Abortion, Induced↗