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The aim of this study was to evaluate the applicability of an intravascular ultrasound contrast agent in examination of the uteroplacental circulation.Uteroplacental circulation in 25 singleton third trimester pregnancies was examined by power Doppler, first without and then with contrast agent enhancement (Levovist \R , Schering AG, Germany). Eight subjects had fetal growth retardation and...
In order to characterize further the human amniotic membrane interferon (IFN-AM), an interferon antigenically unrelated to human IFN-α, -β, and -γ or TNF, we analysed its biological activities. Here, we present direct evidence of its ability to affect cell growth and to induce the IFN-stimulated genes (ISGs) 6–16 and 2′–5′ oligoadenylate synthetase (OAS), in addition to its crossed anti-viral activity...
In order to establish a gestational profile for placental transcellular permeabilities to water, urea and mannitol, syncytiotrophoblast microvillous (MVM) and basal membrane (BM) vesicles were isolated from human placentae obtained from 16 weeks of gestation to term. Using stop-flow/light-scattering techniques the rate of change in vesicle volume in response to an osmotic challenge was measured and...
The purpose of this study was to examine evidence for the presence of activated leukocytes in the fetal membranes from patients with preterm delivery. Polymorphonuclear leukocytes in fetal membranes from seven patients with preterm delivery (26–32 weeks of gestation) were analysed using transmission electron microscopy and ultrastructural enzyme-histochemistry for peroxidase and alkaline phosphatase...
A human embryonal carcinoma (EC) cell line, NCR-G3 (G3), is capable of differentiating into a variety of cell types in vitro, including epithelial, muscle, neural and trophoectodermal cells. The production of human chorionic gonadotropin (hCG), a trophoectoderm-specific hormone, begins 7 days after retinoic acid (RA) treatment and peaks on day 12–13. In this study, we used G3 cells to investigate...
This study examined the electrical properties and Na + transport function of a porcine trophectoderm cell line, TE1, which forms a polarized epithelium in culture. Specifically, the capacity of TE1 cells to generate a transepithelial potential difference, and to modify selectively the Na + , K + and Cl − ionic composition of medium in the apical and basolateral compartments,...
In mice and humans, expression of the tumour necrosis factor receptor-1 (TNF-R1) gene in placental trophoblast cells is constitutive whereas expression of the TNF-R2 gene is developmentally programmed. In order to study the individual functions of TNF-R1 and -R2 in this lineage, cell lines were generated from placental explants of homozygous matings of gestation day 10 outbred mice (Swiss–Webster),...
1939 and the early 1940s saw the publication of a remarkable series of papers on placental transfer. For the first time, a group of investigators made a quantitative and systematic study of the transfer of a simple, presumably inert physiological solute, the sodium ion, in a number of different species at various gestational ages. The driving force behind these studies was Louis Barkhouse Flexner.
This study attempted to determine the placental release of corticotrophin-releasing hormone (CRH) into the umbilical circulation, and the factors which affect it, by measuring venous and arterial levels for CRH across the umbilical circulation in labouring as well as non-labouring elective caesarean section patients. The relationship with measures of fetal oxygenation and acid-base status at birth...
Placental bed biopsies taken during caesarean section from 10 patients with pre-eclampsia and six healthy pregnancies were studied. We applied antibodies against cytokeratin and different macrophage markers to analyse the distribution of invasive extravillous trophoblast cells as compared to that of macrophages in myometrial segments of uteroplacental arteries. The data were evaluated quantitatively...
Lactoferrin (LF) has been found in most biological fluids including amniotic fluid and cervical mucus in pregnant women and is released from neutrophils in response to inflammation. It is an important component of the host defence against microbial infections due to its antimicrobial properties. Premature labour is caused by amniotic infection and high concentrations of inflammatory cytokines in amniotic...
To examine the effect of region and labour upon prostaglandin synthesis in human fetal membranes, intact membranes from three regions, the cervical region, the periplacental region and a region midway between the two, were collected following spontaneous labour and delivery or at elective caesarean section prior to labour. Discs of 2-cm diameter were cut from each of three regions and incubated for...
The goal of this research was to investigate movement of sugars across placental plasma membranes. Changes in vesicle volume produced by solute uptake were measured by light scattering. Analysis, performed by fitting of the light scattering data to exponentials, revealed that for certain sugars such as glucose, a rapid component and a second, slower transport process were present. Measurements in...
Apoptosis and cell proliferation are widely recognized to be important physiological processes which together maintain tissue homeostasis. The apoptotic and proliferative processes in 38 first trimester placentae were quantified using terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling (TUNEL) and an antibody against Ki-67 antigen, respectively. In 14 cases, the estimation of apoptotic...
This study investigated uptake of triiodothyronine sulphate (T 3 S) and interactions between uptake of T 3 S and triiodothyronine (T 3 ) using the human choriocarcinoma cell line (JAr) as a model of placental transport. Cells were incubated at 37°C with 30pm 125 I-T 3 for 2min with unlabelled T 3 (0–30μm) or T 3 S (0–1mm). Addition of an excess...
This review summarizes the experimental evidence supporting the concept that oestrogen has a central integrative role in modulating the communication that occurs between the placenta and the fetus which results in primate fetal–placental development. Thus oestrogen, acting within placental trophoblasts, regulates the functional differentiation of syncytiotrophoblasts, manifested as an upregulation...
In most eutherian mammals, the inner cell mass (ICM) of the blastocyst assumes an almost constantly specific orientation to the uterus at the time of implantation, and this is usually correlated with subsequent positioning of the fetal membranes and chorioallantoic placenta. Although these relationships tend to be conserved between closely related species, this is not the case in the noctilionoid...
Cholesterol transport for steroidogenesis in the human placental mitochondria is an enigma as, contrary to other steroidogenic tissues, the human placenta does not express steroidogenic acute regulatory protein (StAR), a protein known to be required for efficient utilization of cholesterol by adrenal and gonadal mitochondria. These observations suggest the possibility that cholesterol transport in...
Reactive oxygen and nitrogen intermediates (ROI, RNI), such as superoxide anion, nitric oxide (NO) and peroxynitrite, are present in villous trophoblasts and mediate TNF-α-induced apoptosis in other cell types. We therefore proposed that ROI/RNI mediate cytokine-induced apoptosis of cultured villous cytotrophoblasts. Treatment of cultures of highly purified term cytotrophoblasts with TNF-α and IFN-γ...
The metabolism of arachidonic acid results in the production of prostaglandins (PGs), which are involved in the initiation of labour at term and preterm. The fetal membranes are a source of pro-inflammatory cytokines which promote increased PG biosynthesis via increased release of arachidonic acid and its conversion to biologically active metabolites such as PGE 2 and PGF 2α . In the...
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