SEARCH · PubMed Health

Results for “Chorionic Villi”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 901 records · Page 50Linked to original sources

PubMed2004

Corticotropin-releasing hormone peptide and human first-trimester placental growth.

The aim of this study was to determine whether corticotropin-releasing hormone (CRH) regulates human trophoblast cell growth. The results showed that exogenous CRH significantly stimulated human trophoblast proliferation in first-trimester primary cultures. In vivo, CRH was strongly immunolocalised to cytotrophoblastic cells in proliferative cell columns and in chorionic villi. We postulate that CRH may have an important role in early placental development and successful pregnancy.

Cell Division↗

PubMed1994

Laser scanning confocal examination and comparison of nidogen (entactin) with laminin in term human amniochorion.

Indirect immunofluorescence confocal microscopy was used to compare the distribution of nidogen (entactin) and laminin in term human amniochorion. Rabbit antiserum raised against recombinant mouse nidogen was immunoreactive with components of the amniotic epithelial basement membrane, chorion laeve basement membrane and maternally derived capillary basement membranes. Overall anti-nidogen immunoreactivity co-distributes with laminin except in the extracellular matrix of the maternally derived decidua, the embryonically derived trophoblast and the apical surfaces of the amniotic epithelia. These differences lead us to suggest that nidogen and laminin may be independently expressed and are not always complexed together. Original observations include dramatic parallel nidogen rich striations in the decidual layer, the fact that the trophoblastic basement membrane appears to extend inwards forming a boundary layer to degenerate chorionic villi and the finding that the recently discovered collagen type IV rich microtrabeculae of the fibroblast layer also contain nidogen and laminin.

Amnion↗

PubMed1991

Cytoskeletal proteins in chronic villitis of unestablished etiology.

Cytoskeletal proteins (i.e., cytokeratins, vimentin, actin, and desmin) are normally present in the placental chorionic villi and are related to the maintenance of the villous shape, and to the ability of the villi to contract and permit a normal blood flow. In areas of villitis of unestablished etiology, the normal reactivity of these proteins in the villous core around fetal stem vessels disappears, and an increased number of cytokeratin positive cells is identified. The vascular damage in stem villi with villitis could develop ischemia in the villous tree promoting cytotrophoblast proliferation. Increased numbers of these areas could be related with the appearance of abnormal pregnancies.

Chorionic Villi↗

PubMed2004

Syncytiotrophoblast degradation and the pathophysiology of the malaria-infected placenta.

Malaria is associated with excessive parasitic infection of the placenta and a reduction in neonatal birthweight. This study has investigated placental cell death in women with active and past malarial infection. Term placentae, with and without malarial pathology, were obtained from women in The Gambia. Active and past malaria infections were identified in placental sections and histological examination was used to determine the number of villi, the incidence of apoptosis, syncytial degradation, fibrinoid deposition and the frequency of syncytial knots. Placentae with active malaria infection showed erythrocyte adhesion of infected cells to syncytiotrophoblast, syncytial degradation, increased syncytial knotting and, in rare cases, localized destruction of the villi. Past malarial infection was characterized by syncytiotrophoblast disruption and fibrin-type fibrinoid (FTF) deposition. Perivillous FTF deposition was consistent with increased syncytial lesions and both increased lesions and syncytial knots were associated with birthweight reductions. Active malaria infection produced no alteration in placental apoptosis. The numbers of chorionic villi remained unchanged and infiltration of inflammatory cells, although not measured directly, appeared to be non-pervasive within the infected tissue. These observations establish a direct link between malaria parasitic infection and syncytiotrophoblast damage. The placental rejection of parasite-affected syncytia may invoke structural changes to compensate for inadequate placental exchange. Syncytial destruction could have serious implications; impairing fetal growth and in some rare cases, providing a previously unrecognized pathway to congenital infection.

Adolescent↗

PubMed2004

Advanced glycation end products induce secretion of chemokines and apoptosis in human first trimester trophoblasts.

BACKGROUND: We studied the effects of advanced glycation end products (AGEs), which are known to accumulate in patients with diabetes, autoimmune diseases, or that smoke, on human trophoblasts. METHODS: First trimester human chorionic villi of 6-10 week gestation were obtained. Expression and localization of the receptor for AGEs (RAGE) was examined by western blotting and immunohistochemistry. Macrophage inflammatory protein (MIP)-1alpha and MIP-1beta, regulated upon activation, normal T-cell expressed and secreted (RANTES), and human chorionic gonadotropin (hCG) in culture medium were measured by ELISA. Trophoblastic apoptosis was evaluated by the Hoechst 33258 staining and the in situ nick end labeling technique. RESULTS: RAGE was localized in trophoblasts. AGEs significantly stimulated secretion of both MIP-1alpha and MIP-1beta from trophoblasts in a time- and dose-dependent manner. AGEs significantly induced apoptosis and reduced secretion of hCG. Increased secretions of MIP-1alpha and MIP-1beta by AGEs were significantly suppressed by inhibitors of nitric oxide synthase (NOS) or nafamostat mesilate, a synthetic serine protease inhibitor and a suppressor of transcription factor, NF-kappaB activation. These agents also suppressed the effects of AGEs on hCG secretion and trophoblastic apoptosis. CONCLUSIONS: These AGE-mediated changes in trophoblasts may lead to impairment of implantation and placentation. NOS inhibitors or nafamostat mesilate may modify these effects.

Apoptosis↗

PubMed1998

Antenatal genotyping of the blood groups of the fetus.

Antenatal genotyping of the fetus is now in widespread use as an aid to the clinical management in cases where there is the potential of haemolytic disease of the newborn occurring. The rapid diagnosis of an antigen-negative fetus will preclude the requirement for further, potentially risky invasive procedures being performed, whilst the determination of an antigen-positive fetus allows the potential of intensifying obstetric care for this pregnancy. Molecular genotyping is a major clinical application which has led from the determination of the molecular bases of blood group antigens expressed, most of which have been defined at the level of the gene. All assays used are dependent on the Polymerase Chain Reaction amplification of fetal DNA derived from either amniotic fluid or chorionic villi. Recent work has explored the potential of utilising fetal cells found to be present in maternal peripheral blood as a source of nucleic acid for prenatal diagnosis. Using non-invasive methods will preclude exposing mother and fetus to the potential hazards of invasive methods (amniocentesis, chorionic villus sampling and cordocentesis) which include miscarriage, fetal malformations and further maternal alloimmunisation.

Adult↗

PubMed1984

Fetal diagnosis of hereditary diseases. WHO Working Group.

Fetal diagnosis, based on amniocentesis in the second trimester of pregnancy, in conjunction with selective termination of affected pregnancies, is currently one of the most important components in the control of hereditary disease. Extensive experience has been gained with its use in the last decade, and in the hands of experienced investigators it is a safe and reliable procedure. However, there are still significant limitations to its use. Many serious congenital abnormalities cannot be diagnosed because of difficulty in identifying pregnancies at risk. In addition, for mothers at high risk, mid-trimester diagnosis is associated with great anxiety.A method for earlier fetal diagnosis, based on sampling of chorionic villi at 8-10 weeks' gestation, is beginning to enter clinical practice. At present, the technique is still at the research stage, but it has great potential for increasing the acceptability of fetal diagnosis. There is evidence that cytogenetic, biochemical, and DNA analyses can be applied to chorionic villus material, but the ultimate usefulness of the procedure will depend on the associated obstetric risk, which has not, as yet, been clearly defined.

Amniocentesis↗

PubMed1993

Mosaicism in chorionic villus sampling: an analysis of incidence and chromosomes involved in 2612 consecutive cases.

The incidence of chromosome mosaicism was analysed in 2612 consecutive chorionic villus sampling (CVS) cases. True mosaicism was found in five cases (0.19 per cent). Confined placental mosaicism (CPM) occurred in 51 cases (1.9 per cent). The chromosomes most frequently encountered in CPM were 2, 7, 8, and the sex chromosomes. Three types of CPM as proposed by Kalousek et al. (1992) were observed. Cases with CPM had a statistically significant association with spontaneous abortion (chi 2 = 3.92, p < 0.05). Based on the data analysed, we conclude that (1) CPM is as likely to occur in cultured chorionic villi as in the direct preparation; (2) as with amniocyte culture, chromosome 2 mosaicism occurs commonly in villus culture; (3) the incidence of false-positive results can be greatly reduced and concern about maternal cell contamination can be alleviated by using both direct cytotrophoblast preparation and cultured chorionic stroma cells in all cases; and (4) follow-up cytogenetic and obstetrical studies, such as ultrasound and fetal monitoring, should always be considered in cases where CPM is suspected.

Cells, Cultured↗

PubMed2003

Intramural pregnancy with negative maternal serum b-HCG.

We report an extremely rare case of intramural pregnancy with negative maternal b-HCG value. The patient underwent a "myomectomy" but the pathology examination revealed chorionic villi consistent with ectopic pregnancy. Diagnosis is very difficult in cases with menorrhagia and especially when pregnancy is not suspected.

Chorionic Gonadotropin, beta Subunit, Human↗

PubMed1992

Prenatal analyses in a pregnancy at risk for beta-mannosidosis.

Prenatal analyses were performed in the pregnancy of the mother of a patient with beta-mannosidase deficiency. Partial deficiency of beta-mannosidase activity in the chorionic villi indicated a heterozygous fetus and this first-trimester diagnosis was subsequently confirmed by amniocentesis.

Amniocentesis↗

PubMed2002

Uniparental disomy in fetuses diagnosed with balanced Robertsonian translocations: risk estimate.

Forty-two fetuses with non-homologous Robertsonian translocations were analyzed for uniparental disomy (UPD). One fetus with a de novo translocation t(13q;14q) had maternal isodisomy of chromosome 14. In a summary of the published data (including the present study), 315 cases were analyzed for UPD after prenatal diagnosis of balanced Robertsonian translocations, of these two fetuses had UPD, giving a risk estimate of 0.65% (CI 0.2-2.3). This risk justifies the recommendation of UPD analysis in fetuses diagnosed prenatally with Robertsonian translocations, with the emphasis on the chromosomes known to contain imprinted genes, such as 14 and 15. We also discuss the possibility of UPD in offspring of Robertsonian translocation carriers with normal karyotype. Based on the risk for UPD in fetuses with Robertsonian translocation we suggest to test these fetuses for UPD and to do so on amniocytes rather than chorionic villi when the risk for unbalanced karyotype is approximately 1%, comparable to the risk for UPD.

Amniocentesis↗

PubMedDate not supplied

Prenatal diagnosis by fluorescence in situ hybridization on chorionic villus cells: nonsignificance of maternal cell contamination.

We assessed the effect of maternal cell contamination on the sensitivity of prenatal diagnosis by fluorescence in situ hybridization (FISH) on overnight attached mesenchymal chorionic villus cells. Double targets FISHs with X and Y chromosome-specific probes were performed on parallel samples from the same pregnancies: (1) samples of assumed fetal tissue retained during dissection, and (2) samples of suspected maternal tissue discarded during dissection. In the karyotypically male samples the tissue retained during dissection contained 0-3% nuclei with two X-specific signals each. In the tissue discarded from the karyotypically male samples 0-50% of the nuclei had two X-specific signals each. We conclude that given thorough dissection of chorionic villi, the sensitivity of prenatal diagnosis of aneuploidies by FISH on overnight attached samples of this tissue is not critically affected by maternal cell contamination.

Chorionic Villi Sampling↗

PubMed1991

[Prenatal diagnosis and its consequences].

The use of chorionic villi biopsy and amniocentesis as methods of the targeting and invasive prenatal diagnosis involves consecutive problems, which must be balanced with the medical legalization of both procedures.

Amniocentesis↗

PubMed1991

[Results of the cytogenetic prenatal diagnosis in the first and second trimesters of pregnancy].

The authors analyze the results of prenatal diagnosis carried out in women during the first and second pregnancy trimesters. Cytogenetic screening was carried out in risk-group pregnant women, i.e. in women aged over 36, in cases with family history of chromosome mutation or a previous child with chromosome aberration, or a sex-linked disease in one of family members, etc. Chromosome preparations from amniotic fluid cell cultures and 'direct' chromosome preparations from chorionic villi were analyzed. The authors discuss the efficacy of prenatal diagnosis in various pregnancy periods, fetal tissue collection methods and quantities necessary for the examination.

Adult↗

PubMedDate not supplied

Carrier detection and prenatal diagnosis in haemophilia A and B.

Sixty probable carriers of haemophilia from 25 families were studied by using coagulation phenotype and DNA analysis: 33 with haemophilia A and 27 with haemophilia B. Coagulation phenotype was based on factor VIII/IX assay and DNA analysis on the examination of restriction fragment length polymorphisms (RFLPs) within and closely linked to factor VIII or IX: 3 RFLP for factor VIII and 3 for factor IX. The comparison between the coagulation phenotype and RFLP analysis showed the misclassification of 15 females (6 for haemophilia A and 9 for haemophilia B). Four prenatal haemophilia A diagnosis were made by DNA analysis of chorionic villi, taken with a transcervical trophoblastic biopsy, between the 18th and the 11th week.

Chorionic Villi Sampling↗

PubMed1996

Behaviour of two IgG subclasses in transport of immunoglobulin across the human placenta.

The human IgG subclasses are a family of highly related yet distinct molecules. Each of these four subclasses performs a discrete function within the human immune system. Previous studies have shown that one of these molecules, hIgG2, may be discriminated against in transport across the human placenta. We have aimed to elucidate the mechanism of this discrimination in order to gain a more comprehensive understanding of the process of transport of immunoglobulin across the human placenta. We have used a combination of immunocyctochemical localisation and biochemical analysis to detail the behaviour of hIgG2. Confocal laser scanning microscopy was used to compare the localisation of hIgG1 (chosen as representative of the efficiently transported subclasses) and hIgG2 in term and first trimester chorionic villi. Complementary evidence was provided from immunoblot analysis of isolated placental coated vesicles. The data presented here suggest that the hIgG2 is transported into the syncytiotrophoblast and appears to accumulate in the stroma of the villi. This leads us to the hypothesis that the fetal capillary endothelium is the cellular impediment to the transport of hIgG2 into the fetal circulation.

Biological Transport, Active↗

PubMed1998

Prospective prenatal investigations on potential uniparental disomy in cases of confined placental trisomy.

In most reported cases of uniparental disomy (UPD) associated with confined placental mosaicism (CPM), a high level of mosaicism or a full trisomy was found in chorionic villi. At the time that we started our investigations, it was not quite clear whether fetal UPD also existed in the more frequently occurring low levels of mosaicism. During a 4-year period, a follow-up amniocentesis was performed in all cases of mosaic or non-mosaic trisomy detected in chorionic villus (CV) semi-direct preparations and suspected to be confined to the placenta. We performed fluorescent in situ hybridization (FISH) on uncultured amniotic fluid cells to differentiate between generalized mosaicism and CPM. We found 29 cases of CPM and we determined the incidence of UPD in 23 of these cases. Normal biparental chromosome contributions were found in 22 cases. In one case, we detected a maternal heterodisomy for chromosome 16. UPD appeared to be a rare phenomenon in the cases of CPM (type I and/or type III) that we encountered in 3958 consecutively investigated CV samples, and is not the cause of the pregnancy complications found in seven out of 23 cases with CPM.

Amniocentesis↗

PubMed1985

Trophoblast samples suitable for long-term culture.

Chorionic villi were obtained by a direct vision technique. Villi without vessels (38 cases) failed to grow in vitro, irrespective of the amount of tissue. Vascular villi with an estimated weight exceeding 5 mg (71 cases) grew in vitro--with two exceptions.

Biopsy↗