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PubMed1995

[Contemporary biopsy for diagnosis of abortion residues: preliminary experience].

The differential diagnosis between abortion and ectopic pregnancy has important clinical implications. In this report we have tested the accuracy of frozen sections in uterine curettings to identify intrauterine pregnancy. Uterine curettings with a diagnosis of products of gestation, from 104 patients were studied. In all of them plasmatic levels of B Gonadotrophin were measured. The curetting material was fixed and studied on frozen sections and on paraffin embedded tissue. A high positive relationship between frozen and embedded material was observed. The sensibility, specificity, positive and negative predictive value of the frozen section to detect chorionic villi were 90.6; 100; 100 and 74% for each of them.

Abortion, Incomplete↗
PubMed1984

[Enzyme histochemical studies of the swine placenta. Histoptics of enzymes in interareolar placental epithelia].

In porcine interareolar placental epithelia, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetylhexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, nonspecific esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that most of the enzyme activities remained almost unchanged during the period of investigation. Only G-6-PDH and 6-PGDH activities increased within the uterine epithelium and nonspecific esterase activity within uterine as well as chorionic epithelia during the 2nd half of pregnancy. Within chorionic and uterine epithelia, hydrolases but not dehydrogenases demonstrated a higher activity at the bases of chorionic villi as compared to the apices and flanks of the latter. The action and influence of the demonstrated enzymes on metabolism, energy transfer, secretory, and resorptive activities of chorionic and uterine epithelia are discussed.

Animals↗
PubMed1987

Confined chorionic mosaicism in prenatal diagnosis.

Confined chorionic mosaicism, detected commonly on chorionic villus sampling (CVS) and occasionally in cultured amniotic fluid cells, is described in five pregnancies that showed confined chorionic mosaicism for trisomies 12, 13, 14, 17 and a marker chromosome. Cytogenetic findings in these pregnancies support the conclusion that within chorion some chromosomal mosaicism are confined to the trophectoderm derivatives while others to the extra-embryonic mesoderm. The etiology of confined chorionic mosaicism is discussed in relation to a significant role of multiple cell lineages contributing to the early development of placenta. The need is indicated for the use of both direct and long-term cultures in CVS prenatal diagnosis, and for the confirmatory testing of fetal blood or amniotic fluid in cases where mosaicism is detected in chorionic villi.

Adult↗
PubMed1999

[Effect of mifepristone on cell-cycle kinetics of human placental chorio-trophoblastic and decidual cell].

OBJECTIVE: To study the effects of mifepristone on cell-cycle kinetics of human placental chorio-trophoblastic and decidual cells. METHODS: Flow-cytometry was introduced in the study of the mechanism of early pregnancy terminating drug, mifepristone. Twenty-three samples were obtained from normal pregnant women by surgical aspiration. Another 24 samples were obtained in women pretreated with 150 mg mifepristone 48 hours before operation. RESULTS: The percentage of the cytotrophoblastic cells in G0 + G1 phases was much higher in the treatment group (P < 0.01), whereas it was much lower (P < 0.01) in G2 + M phases, and the proliferating index of cells was significantly decreased. Apart from the increasing of decidual cells in G2 + M phases (P < 0.05), there was no change in other phases. CONCLUSIONS: Mifepristone may block the transformation of the cytotrophoblastic cells from G0, G1 phases to S phase, thus leading to the block of the proliferation of cells. Mifepristone has much more significant effects on the chorionic villi than on the decidua.

Abortifacient Agents, Steroidal↗
PubMed1991

[Immunohistochemical localization of cytochrome P-450].

Distribution of different forms of cytochrome P-450 (forms C, D and B) in human placenta by immunohistochemical methods on light microscopy level with colloid gold was studied. Positive reaction with cytoplasm of endothelial cells, called the "epithelioid" plates of chorionic villi was found. Trophoblastic and stromal cells were not stained.

Chorionic Villi↗
PubMed1987

Prenatal diagnosis of cystinosis utilizing chorionic villus sampling.

The prenatal diagnosis of cystinosis is currently based on the increased amount of free-cystine present in amniotic fluid cells. Amniocyte cultures must be grown for at least 2 weeks to obtain sufficient cells for such measurements. Thus, the diagnosis cannot be made until close to 20 weeks gestational age by this method. We report a case in which chorionic villi were used for direct cystine measurement resulting in the in utero diagnosis of cystinosis at 9 weeks gestational age. The diagnosis was confirmed by the study of cultured chorionic villus cells, and of the 10-week abortus.

Chorionic Villi↗
PubMed1987

First trimester prenatal diagnosis of metabolic diseases: a survey in countries from the European community.

This paper presents the collected data concerning First Trimester Prenatal Diagnosis of Metabolic Diseases performed in different countries of the European Community by enzymatic methods using chorionic villi. In all, 258 diagnoses were made for 38 different metabolic diseases and 56 (22 per cent) affected fetuses have been detected. Several difficulties were encountered with regard to chorionic villus material or enzyme expression in this tissue. We stress the conditions necessary for avoiding errors in diagnosis.

Cells, Cultured↗
PubMed1987

Localization of insulin-like growth factor-binding protein and endometrial beta-lactoglobulin in cultured decidual and chorionic villus cells.

Immunofluorescence staining was used to localize two 'endometrial' proteins, insulin-like growth factor-binding protein and human beta-lactoglobulin homologue, in cultured cells of chorionic villi and decidua. Both cultured cell types were positive for each protein. These results indicate that immunohistochemical detection of these two proteins cannot be used to distinguish between cultured chorionic villus and decidual cells.

Carrier Proteins↗
PubMed1990

Prospective study of amniocentesis performed between weeks 9 and 16 of gestation: its feasibility, risks, complications and use in early genetic prenatal diagnosis.

This paper demonstrates that the outcome of amniocenteses performed between the 9th and the 14th weeks is similar to that of amniocenteses performed between the 15th and 20th weeks. We have performed and prospectively followed 615 amniocenteses between the 9th and 16th weeks of gestation. The outcome, risks, and complications are similar to those of amniocenteses at the usual time (after 15 weeks) and to the other groups of early amniocentesis (before 15 weeks). Early amniocentesis differs from amniocentesis at the usual time in that it carries higher rates of fetal losses and of amniotic fluid leakage, more confined cytogenetic abnormalities, and an increased number of patients who have the procedure postponed. Two cultures (0.32%) failed to produce results, 595 (96.7%) samples were obtained at the first tapping, 20 (3.3%) at the second attempt. alpha-Fetoprotein levels reach their maximum at 13 weeks. Amniocenteses between 15 and 16 weeks (293, or 47%) constitute the control group, those between 9 and 14 weeks (322) the experimental group. Early amniocentesis appears to be a safe early genetic prenatal diagnosis technique, an alternative to chorionic villi sampling.

Amniocentesis↗
PubMed2002

Expression and localization of angiogenin in placenta: enhanced levels at term over first trimester villi.

Human angiogenin, a 14-kDa non-glycosylated polypeptide with both angiogenic and ribonucleolytic activities, is implicated in angiogenesis, a complex process of proliferation and formation of new capillary blood vessels from existing blood vessels. Placental growth requires extensive angiogenesis, which develops its vascular structure in both fetal chorionic villi and maternal deciduas. In this study, we investigated the expression profiles of angiogenin in placental villi from early and late gestation at both mRNA and protein levels using explant cultures in vitro followed by RT-PCR, immunoblot, and immunohistochemical analyses. From functionally active placental explants, angiogenin was detected in conditioned media of all the samples from first trimester and term group. The mean levels of angiogenin produced by term villi were found to be 2.6-, 2.1-, and 2.2-fold higher (P < 0.01) than first trimester villi at 24, 48, and 72 hr of culture, respectively. Expression profiles of angiogenin from term and first trimester villi seem to agree with its mRNA levels and immunoblot analysis; the expression in term villi was twice that in first trimester villi. The presence of angiogenin in placental villi and upregulation of its production towards term indicate that angiogenin production by the placenta is specific to the developmental stage. In conclusion, the observed changes in the localization and mRNA expression of angiogenin during placental development raise the possibility that it is involved in morphological and angiogenic changes in this endocrine organ vital to the successful fetal outcome during pregnancy.

Adult↗
PubMed1999

Expression of trophinin, tastin, and bystin by trophoblast and endometrial cells in human placenta.

Trophinin, tastin, and bystin comprise a complex mediating a unique homophilic cell adhesion between trophoblast and endometrial epithelial cells at their respective apical cell surfaces. In this study, we prepared mouse monoclonal antibodies specific to each of these molecules. The expression of these molecules in the human placenta was examined immunohistochemically using the antibodies. In placenta from the 6th week of pregnancy, trophinin and bystin were found in the cytoplasm of the syncytiotrophoblast in the chorionic villi, and in endometrial decidual cells at the utero placental interface. Tastin was exclusively present on the apical side of the syncytiotrophoblast. Tissue sections were also examined by in situ hybridization using RNA probes specific to each of these molecules. This analysis showed that trophoblast and endometrial epithelial cells at the utero placental interface express trophinin, tastin, and bystin. In wk 10 placenta, trophinin and bystin were found in the intravillous cytotrophoblast, while tastin was not found in the villi. After wk 10, levels of all three proteins decreased and then disappeared from placental villi.

Antibodies, Monoclonal↗
PubMedDate not supplied

Villous sprouting: fundamental mechanisms of human placental development.

There is increasing evidence that maldevelopment of the placental villous tree can play an important role in the pathogenesis of various pregnancy diseases. In this review we present the most recent advances of cellular and molecular mechanisms involved in the early formation of chorionic villi. In particular we focus our attention on the structural events during early villous sprouting leading to the formation of the mesenchymal villi which are the forerunners of all other villous types, i.e. immature intermediate villi, stem villi, mature intermediate villi and terminal villi. Early villous sprouting starts as 'hot spots' which are circumscribed areas consisting of highly proliferating cytotrophoblastic and stromal cells. The post-proliferative cytotrophoblastic cells fuse with the overlying syncytium leading to the formation of the trophoblastic sprouts. When villous mesenchyme invades the trophoblastic sprouts, the latter are transformed into villous sprouts. The vascularization of the villous sprouts leads to the formation of the mesenchymal villi, the most basic villous type. This process is repeated throughout pregnancy. We analyse the influence of various extracellular matrix molecules, e.g. tenascin and hyaluronic acid, on the formation of hot spots and mesenchymal villi as well as the transformation of the latter in other villous types. We present a critical survey on the data on vessel formation related to villous sprouting and morphogenesis of mesenchymal villi as well as the expression of various angiogenic factors and their receptors.

Chorionic Villi↗
PubMed1989

Early human trophoblast cell cultures. A morphological and immunocytochemical study.

Rapidly growing cytotrophoblasts were isolated from early human chorionic villi and the Papanicolaou method was used to characterize their cytology and transformation into syncytiotrophoblasts. Cytotrophoblasts fused and formed binucleated cells or mononucleated intermediate cells. Syncytial cells were formed by fusion of small cytotrophoblasts or intermediate cells and cytotrophoblasts. Glycosaminoglycans were produced in cytotrophoblasts and released extracellularly. Here they were accumulated and/or diffused into a continuous layer covering the cells. Glycosaminoglycans in syncytial cells were contained in well defined membranous sacs. Cytotrophoblasts only grown beyond confluence differentiated into villi with a villus-like histology.

Cells, Cultured↗
PubMed2005

Flow cytometric characterisation of cells of differing densities isolated from human term placentae and enrichment of villous trophoblast cells.

Cells were isolated from human term placentae by trypsinisation of fragments of chorionic villi and fractionation of cells on a Percoll density gradient into six layers. A panel of 10 monoclonal antibodies to antigens on or in trophoblast cells (placental alkaline phosphatase (PLAP), cytokeratin-7, beta-human chorionic gonadotrophin (beta-hCG), human leucocyte antigen-G (HLA-G)), leucocytes (CD45), monocytes, macrophages, dendritic cells, B cells (HLA class II), mesenchyme cells (vimentin), fibroblasts (fibroblast antigen) and nucleated cells excluding villous trophoblast (HLA class I, CD9) was used to characterise the cells by flow cytometry. For staining intracellular antigens (cytokeratin, vimentin, beta-hCG) the cells were first fixed and permeabilised. The upper two layers from the gradient (density 1.013-1.039 g/ml) contained predominantly PLAP-positive cells or fragments, probably derived from the syncytiotrophoblast. Cytokeratin-positive cells accumulated mainly in the layer of density 1.039-1.052 g/ml and comprised the majority of the cell types identified in this fraction. Few or no cells reactive with antibodies to beta-hCG or HLA-G were identified in any layer. Non-trophoblast cells were heavier, being present mainly at densities 1.052-1.079 g/ml (CD45, HLA class I, vimentin) and 1.066-1.092 g/ml (fibroblast). Fewer than 10% of cells in any layer were HLA class II- or CD9-positive. Further purification of trophoblast cells was by negative immunomagnetic separation with removal of CD45-positive cells and HLA class II-positive cells to less than 1%. On culture of the cells from each layer, those of density 1.039-1.066 g/ml exhibited characteristics of cytotrophoblast cells; they secreted high levels of human chorionic gonadotrophin and formed adherent multinucleate cells. This procedure enabled the selection and enrichment of cytotrophoblast cells and/or syncytiotrophoblast fragments that are suitable for cellular and molecular studies.

Cell Count↗
PubMed1989

Interpretation of chorionic villus sampling laboratory results is just as reliable as amniocentesis.

Karyotypes of chorionic villi have been said to be less accurate than karyotypes of amniocytes. Karyotypic differences between placental and fetal tissue and maternal-cell contamination could potentially complicate clinical management. We compared cytogenetic results obtained by chorionic villus sampling and amniotic fluid cells in our center during a 2-year period (1986-1987). Chorionic villus sampling material was processed for direct analysis and backed up when indicated (now routinely) with tissue cultures. The incidence of inconclusive results requiring additional studies was 1.2% for chorionic villus sampling and 0.75% for amniotic fluid cells. Mosaicism was the most common problem for both chorionic villus sampling and amniotic fluid cells. Failure of growth was more frequent in amniocentesis material (0.35 versus 0.09%), but polyploidy and atypical aneuploidies were greater with chorionic villus sampling. The accuracy of cytogenetic evaluation by chorionic villus sampling and amniotic fluid cells and the need for additional invasive procedures appear to be equal in our laboratory.

Amniocentesis↗
PubMed1991

Sister chromatid exchange (SCE) frequencies differ between directly prepared cytotrophoblasts and cultured mesenchymal core cells.

Analysis of sister chromatid exchange (SCE) in chorionic villus cells may become useful in measuring the response of fetal tissues to clastogens or mutagens or for prenatal diagnosis of chromosome breakage syndromes such as Bloom syndrome. Previous studies have failed to analyze cytotrophoblastic cells and mesenchymal core cells, or have found no difference between SCE frequencies in directly prepared and cultured cells. Our data indicate significant differences in SCE frequencies between the two cell types: SCE frequency in directly prepared cytotrophoblasts was 6.73 SCE/cell +/- 1.6, whereas SCE frequency in cultured mesenchymal core cells was 10.31 SCE/cell +/- 0.49 (P less than 0.001). SCE analyses involving chorionic villi must take into account cell type.

Animals↗
PubMed1988

Prenatal diagnosis of beta-thalassaemia by second-trimester chorionic villus sampling.

In this study we evaluated the feasibility of second-trimester transabdominal chorionic villus sampling for prenatal diagnosis of beta-thalassaemia in 80 pregnancies at risk presenting in the second trimester at the Antenatal Service. Sampling was carried out from 13 to 20 weeks and was successful in all cases. The amount of chorionic villi obtained varied from 10 to 40 mg, which was sufficient to make fetal diagnosis by oligonucleotide analysis within 10 days from sampling in all cases. No fetal losses occurred. From these results we conclude that transabdominal chorionic villus sampling is a useful procedure for prenatal diagnosis of beta-thalassaemia in those couples presenting after the first trimester.

Biopsy, Needle↗