Search PubMed⌕ Search

Biomedical subjects

F J Los

Publications and source records attributed to F J Los.

79 records · Page 5Linked to original sources
PubMed1989

Selective birth in a dyzygotic twin pregnancy with discordancy for Down's syndrome.

The discovery of a twin pregnancy by ultrasound at the intake procedure for chorionic villus sampling or amniocentesis is not unusual because of the raised incidence of dizygotic twins at increased maternal age. Since the conception of dizygotic twins is genetically a separate and unrelated event, the risk of abnormalities in each twin is independent, but additive. In advanced maternal age, the risk of chromosomal aneuploidy in one of both fetuses varies between 2 and 6% [1]. This case report discusses the early prenatal diagnosis of twins discordant for Down's syndrome.

Abortion, Eugenic↗
PubMed1979

Raised maternal serum-alpha-fetoprotein levels and spontaneous fetomaternal transfusion.

Study of blood smears showed that spontaneous fetomaternal transfusions were significantly more common among 42 pregnant women with raised serum-alpha-fetoprotein (AFP) levels than among 45 pregnant women with normal serum-AFP levels. Raised serum-AFP was associated with a spontaneous fetomaternal transfusion of greater than or equal to 0.1 ml in at least 21 of the 42 women in the study group.

Amniocentesis↗
PubMedDate not supplied

AFP transport across the fetal membranes in the human.

In this investigation the original observation of a correlation between the concentration of amniotic fluid albumin and maternal serum alpha fetoprotein (AFP), as a proof for amniotic fluid-derived AFP in the maternal compartment is confirmed at 15 and 16 weeks of gestation. In contrast to the earlier reported highly significant relation in this study the correlation is only weak, especially at 15 weeks. This might be in agreement with a more frequent absence of raised maternal serum AFP levels in cases of raised amniotic fluid AFP levels prior to 16 weeks of gestation. Transamniotic AFP transport contributes a minor part of the AFP present in the maternal compartment, as also indicated by the lack of correlation between AFP concentrations in amniotic fluid and maternal serum.

Albumins↗
PubMedDate not supplied

Prevalence of tetraploid metaphases in semidirect and cultured chorionic villi.

OBJECTIVE: Investigation of the normal frequency of tetraploid metaphases in semidirect (STC) and cultured (LTC) chorionic villi. METHODS: Fifty metaphases in STC- and in LTC-villi slides of 100 women of advanced maternal age were screened for tetraploidy. RESULTS: Up to three tetraploid metaphases were encountered in 27% of the STC-villi preparations; the scores fitted a Poisson distribution. In all LTC-villi preparations tetraploid cells were seen; the scores fitted a log-Gaussian distribution. CONCLUSIONS: On the basis of these distributions, we propose a protocol for the management of tetraploid metaphases in chorionic villi, strongly reducing the number of prenatal follow-up investigations.

Cells, Cultured↗