Cell-Derived Microparticles and Complement Activation in Preeclampsia Versus Normal Pregnancy

SummaryImmune-mediated platelet activation is emerging as an important pathogenic mechanism of thrombosis. In vitro studies have suggested two distinct pathways for immune-mediated platelet activation; one involving clustering of platelet FcyRIIa, the other involving platelet-associated complement activation. HLA-related antibodies have been shown to cause platelet aggregation, but the mechanism has not been clarified. We evaluated the mechanism of platelet aggregation induced by HLA-related antibodies from nine patients. Antibody to platelet FcyRIIa failed to block platelet aggregation with 8/9 samples, indicating that engagement of platelet FcyRIIa is not necessary for the platelet aggregation induced by HLA-related antibodies. In contrast, platelet aggregation was blocked by antibodies to human C8 (5/7) or C9 (7/7). F(ab’)2 fragments of patient IgG failed to induce platelet activation although they bound to HLA antigen on platelets. Intact patient IgG failed to aggregate washed platelets unless aged serum was added. The activating IgG could be adsorbed by incubation with lymphocytes and eluted from the lymphocytes. These results indicate that complement activation is involved in the aggregation response to HLA-related antibodies. This is the first demonstration of complement-mediated platelet aggregation by clinical samples. Five of the patients developed thrombocytopenia in relationship to blood transfusion and two patients developed acute thromboembolic disease, suggesting that these antibodies and the complement-dependent pathway of platelet aggregation may be of clinical significance.

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Ultrasonographic Measurement of Fetal Foot Length and Femur/Foot Length Ratio in Second Trimester of Normal Pregnancy in Korean Women

Journal of the Korean Radiological Society ◽

10.3348/jkrs.2001.44.6.715 ◽

2001 ◽

Vol 44 (6) ◽

pp. 715

Author(s):

Eun Kyung Ji

Keyword(s):

Normal Pregnancy ◽

Length Ratio ◽

Korean Women ◽

Second Trimester ◽

Foot Length

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EFFECT OF FEEDING ETHINYLOESTRADIOL FOR VARIOUS PERIODS BEFORE MATING ON REPRODUCTION IN THE HAMSTER

Acta Endocrinologica ◽

10.1530/acta.0.0700582 ◽

1972 ◽

Vol 70 (3) ◽

pp. 582-590

Author(s):

B. K. Davis ◽

I. Noske ◽

M. C. Chang

Keyword(s):

Single Dose ◽

Pregnancy Rate ◽

Fertility Control ◽

Normal Pregnancy ◽

Oestrous Cycle ◽

The Other ◽

Feeding Schedule ◽

Crown Rump Length ◽

Essentially Normal ◽

Effect Of Feeding

ABSTRACT Ethinyloestradiol (EO) fed for various periods before mating to female hamsters affected the timing of mating and pregnancy rate. Slight effects on ovulation, foetal-crown rump length and resorption may have occurred, but effects on implantation were not apparent among pregnant hamsters. The response observed depended upon the feeding schedule adopted: hamsters fed 2.5 mg EO in a single dose, on day 3 before mating, mated normally but had a significantly lower pregnancy rate; on the other hand, animals fed 2.5 mg EO (0.21 mg/day) over three oestrous cycles, days 14–3 before mating, showed variations in the time of mating but had an essentially normal pregnancy rate; and, a group of hamsters who received the same total amount of EO (0.63 mg/day) over one oestrous cycle, days 6–3 premating, showed untowards effects by the steroid on both the timing of mating and pregnancy rate. The implications of these results are considered in relation to fertility control.

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The activation of RANK/RANKL/OPG system in normal pregnancy and pre-eclampsia

Bone Abstracts ◽

10.1530/boneabs.1.pp479 ◽

2013 ◽

Author(s):

Dorota Darmochwal-Kolarz

Keyword(s):

Normal Pregnancy

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Pathological features of the sequence in pregnant women with delayed fetal growth

HEALTH OF WOMAN ◽

10.15574/hw.2019.140.50 ◽

2019 ◽

pp. 50-54

Author(s):

V.O. Golyanovskiy ◽

◽

Ye.O. Didyk ◽

Keyword(s):

Pregnant Women ◽

Intrauterine Growth Restriction ◽

Normal Development ◽

Intrauterine Infection ◽

Normal Pregnancy ◽

Growth Restriction ◽

Control Group ◽

Intrauterine Growth ◽

Increased Risk ◽

Infection And Inflammation

Pregnant women with intrauterine growth restriction (IUGR) have an increased risk of adverse perinatal and long-term complications compared with the birth of children with normal body weight. Thus, IUGR is one of the main challenges for the global health system, especially in poor and developing countries. Morpho-functional studies of the placentas help in determining the causes of IUGR, and therefore, timely prevent complications in pregnant women with IUGR. The objective: The purpose of this study is to investigate various morphometric and pathomorphological changes in the placenta, including inflammatory, in cases of IUGR, and to establish a correlation of these results with the etiology and complications for the fetus. Materials and methods. In the current study, 54 placentas of the fetuses with IUGR (the main group) were compared with 50 placentas of the fetuses with normal development (control group). The criteria for the inclusion of IUGR were gestational age more than 30 weeks and all fetuses with a weight less than 10th percentile for this period of pregnancy. The placenta material was studied pathomorphologically with laboratory screening for infection and inflammation. Similarly, the results were determined for placentas of the fetuses with normal development compared to placentas with IUGR. Results. The placenta study showed the presence of calcification in the case of IUGR, as well as in the case of prolonged pregnancy. However, calcification of the placenta in the case of IUGR was more progressive compared with placenta in the normal pregnancy. In addition, the presence of intrauterine infection and inflammation was observed, which could also lead to an adverse outcome for the further progression of pregnancy with IUGR. Conclusion. A comparative macro- and microscopic pathomorphological study of the placentas in the two groups has shown a significant increase in the pathological changes in all the anatomical structures of the fetuses with IUGR. Key words: Intrauterine growth restriction (IUGR), fetal weight, pathomorphological changes of the placenta.

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