It seems that the majority of sera from women with unexplained spontaneous abortions are teratogenic to rat embryos in culture. In about two-thirds of these sera the teratogenic factor(s) seem to be present in the IgG fraction.
It is generally believed that some human miscarriages result from embryotoxic factors existing in the sera. To study the embryotoxicity of such sera, 3.5-day-old mouse blastocysts were cultured for 72 h on 80% sera from different groups of women. After 72 h there was no blastocystic development in 53.2% of the cases grown on sera from women after two or more miscarriages, and none in 33.6% of the blastocysts grown on sera from women after one miscarriage, as compared with 8.2% and 12% respectively on control sera. Sera from women with miscarriages were divided into 'high risk' (50% or more embryotoxicity) and 'low risk' (less than 50% embryotoxicity) sera. The 'high risk' sera from two or more miscarriages caused an average of 72.1% undevelopment, while the 'low risk' sera (less than 50% embryotoxicity) from the same group caused 33.6% undevelopment. The 'high risk' sera from one miscarriage were embryotoxic to 55.8% of the blastocysts and the 'low risk' sera from the same group caused only 8.7% undevelopment. No significant differences were found in the mean serum concentrations of folic acid, zinc and copper of many of the experimental groups, in comparison with controls. The embryotoxic factor/s which exist in the 'high risk' sera from women with miscarriages are still not known.
The results of combined ritodrine and indomethacine treatment (RI) in premature labor contractions were compared with ritodrine alone (R). One hundred and twenty patients with threatened premature labor in weeks 26-34 were studied. Sixty RI women received 100 mg ritodrine in infusion followed by 60 mg daily orally until 35 weeks and indomethacine 200 mg on the first day of treatment only. The R group included 60 women with identical tocolysis indices, age of pregnancy and anamnestic parameters who received ritodrine only. The mean prolongation index (PI) was 18.2 in the RI group, against 11.5 in the R patients (P less than 0.05). The mean prolongation of pregnancy was 5.6 weeks in the first and 3.6 in the control group (P less than 0.05). Birthweight and Apgar scores were similar in the two groups. In order to examine the possible early closure of the ductus arteriosus due to the indomethacin therapy, echocardiograms were done on all newborn in the RI group: the pre-ejection period and right ventricular ejection time ratio was 0.19-0.26 after delivery and 0.17-0.22 1 month later, which excludes pulmonary diastolic hypertension due to premature closure of the duct. The combined RI treatment is more effective that R alone and does not give rise to any complications in the mother or the fetus.
We studied 27 embryos of 5–12 weeks gestational age where pregnancy was interrupted due to paramedical reasons, in order to find the developmental stages at which matrix vesicles appear in cartilage, and whether they are involved in the mineralization process. Specimens of long bones, lumbar and thoracic vertebral column were prepared for light, transmission and scanning electron microscopic studies. In the cartilaginous models of long bones, matrix vesicles were found amongst maturing and hypertrophic chondrocytes already by the 6th week after fertilization. By that stage, bone rudiments consisted of only cartilage that was not yet mineralized. In the vertebral column matrix, vesicles were found in the vertebral bodies amongst maturing and hypertrophic chondrocytes at the beginning of the 8th week. At that stage, although hypertrophy of chondrocytes was observed, mineralization was still absent. No matrix vesicles were found in the perichondrium, investing mesenchyme and intervertebral discs. Mineralization of cartilage in long bone rudiments started in the form of hydroxyapatite crystals within or around the matrix vesicles at 7 weeks of age and in the vertebral column at 11 weeks. As mineralization progressed, more hydroxyapatite crystals were observed around the matrix vesicles, forming typical calcospherites. Mineralization then progressed in the form described in other animals.
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