Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “AMNION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 307 records · Page 17Linked to original sources
PubMed1990

Effect of amnionitis on the complement system of preterm infants.

The development of the complement system was studied by quantitation of total hemolytic complement activity (CH50), C1q, C3, C4, and C3 split product (C3d) in cord plasma of nine human fetuses (17-22 weeks of gestation), 110 preterm (24-36 weeks of gestation) and 30 term neonates. The complement levels were analyzed in relation to various illnesses of preterm infants. Histological examination of the placenta revealed a higher incidence of amnionitis in the placenta of less than 34 gestational weeks. In cases without amnionitis, there were significant correlations between complement levels and gestational age. In cases with amnionitis, the complement system was activated even in infants of less than 28 weeks gestation. The complement levels correlated with the extent of the inflammation in the placentas and umbilical cords except for C1q. In infants with Wilson-Mikity syndrome, complement levels other than C1q were significantly elevated in comparison with those of infants with respiratory distress syndrome. In the group of preterm infants without amnionitis, no differences were found between infants with intrauterine growth retardation and those with growth appropriate for gestational age.

Chorioamnionitis↗
PubMed1997

Fetal breathing movements within 24 hours of delivery in prematurity are related to histologic and clinical evidence of amnionitis.

Our objective was to determine the association of fetal breathing movements (FBM) within 24 hr of delivery, with the clinical diagnosis of chorioamnionitis and histologic evidence of severe acute amnionitis and umbilical-chorionic vasculitis in women delivering at < 32 weeks' gestation. We performed a cohort study of patients with singleton gestations delivered at < 32 weeks' following preterm labor with intact membranes and sonographically assessed biophysical profile within 24 hr of delivery (n = 111). Patients with FBM were compared with those without FBM, with regard to prevalence of clinical chorioamnionitis (CA) and histologic diagnosis of acute amnionitis and umbilical vasculitis. Maternal and neonatal charts were reviewed and the diagnosis of clinical CA made by previously established criteria. Histologic presence and extent of acute intrauterine inflammation was assessed and scored by a single pathologist blinded to clinical information. Results are presented as chi 2 values and odds ratios with 95% confidence intervals. Of the patients included in the study, FBM were absent in 56 and present in 55. The prevalence of CA was 13% (15 of 111), severe acute amnionitis 34% (38 of 111), and severe umbilical vasculitis 23% (26 of 111). Severe umbilical vasculitis was significantly less frequent in cases with FBM as compared to cases without FBM (15% [8 of 55] vs. 32% [18 of 56], p = 0.049). However, the difference in rate of CA (22% [12 of 55] vs. 34% [19 of 56], p = 0.22) and histologic severe amnionitis (29% [16 of 55] vs. 39% [22 of 56], p = 0.4) between cases with and without FBM was not significant. In the presence of preterm labor with intact membranes, absence of FBM had sensitivities of 73 and 72%, and specificities of 54 and 56% in the prediction of CA and histologic evidence of umbilical vasculitis, respectively. We conclude that absence of FBM is associated with histologic evidence of fetal inflammation in intrauterine infection in patients with preterm labor and intact membranes delivering at < 32 weeks. However, the low positive predictive value of absent FBM in predicting fetal inflammation in intrauterine infection should discourage the guidance of clinical management in patients < 32 weeks' gestation with preterm labor and intact membranes.

Adult↗
PubMed1981

[Prolactin in amnionic fluid and serum of women in early pregnancy (author's transl)].

Transvaginal amniocentesis performed in 257 women in the first trimester of pregnancy produced 99 samples of the amnionic fluid. Prolactin was determined in all samples of the amnionic fluid and in the serum of all pregnant women. In the amnionic fluid there were very small amounts of prolactin in the early days of pregnancy, from 5 to 6 weeks. Prolactin values remained the same, in spite of large individual oscillation, up to the 11th week of pregnancy. After 11th week of pregnancy the content of prolactin rapidly goes up, so that in the 15th and the 16th week it reaches its mean value of 1183.43 micrograms/l. In the serum of pregnant women prolactin exceeds the value of the luteinic phase (outside pregnancy) only in the 7th week, although in some women examined it remains below these values up to the 13th week. After the 13th week there is a slow, linear increase of serum prolactin with the advance of pregnancy. No significant correlation was found between prolactin values in the amnionic fluid and the serum of pregnant women.

Amniotic Fluid↗
PubMed1961

Pathogenicity for suckling mice of Coxsackie viruses adapted to human amnion cells.

Continuous passages in primary human amnion cell cultures of Coxsackie prototype viruses A-9, A-10, A-11, A-13, A-14, A-15, A-18, B-1, B-2, B-4, and B-5 increased the titers, hastened and enhanced cytopathic effect, and in varying degrees caused loss of virulence for newborn mice. Only B-3 behaved differently in that neither adaptation to cells in vitro nor attenuation with respect to the original animal host could be observed. Types A-15, B-1, B-2, and B-5 slowly regained virulence when passed in mice after high concentration passages in amnion cells whereas all other viruses reverted to their original virulence after only 1 or 2 passages in the animal host. When these strains, however, were purified by cloning procedures, they too showed markedly increased stability. In all stages of attenuation, viruses multiplied extensively in vivo as could be shown by titration in amnion cell cultures. It is suggested that a genetic mechanism is operative leading to virus populations in which the majority of the particles is qualitatively changed.

Amnion↗
PubMed2001

Enhanced dehydroepiandrosterone synthesis by amnion compared to chorion: a comparative study using the reverse-isotope dilution technique.

With a view to establishing whether the term human fetal membranes possess the enzymic ability to synthesize dehydroepiandrosterone (DHEA) from pregnenolone, homogenates of amnion and chorion obtained from women (n = 5, age 27-34 years) after spontaneous labor at term (37-42 weeks gestation) from uncomplicated pregnancies were incubated with [7n-3H]pregnenolone as substrate. Reverse-isotope dilution analysis gave positive identification of [3H]DHEA acetate in all incubations of viable tissues. No such metabolite was evident in control incubations with heat-denatured tissues. Virtually radiochemically pure esters under three recrystallizations were obtained with mean concentrations of between 15787 and 30137 dpm mol(-1) for amnion which was considerably higher than that of chorionic tissues at 4316-5528 dpm mol(-1). The magnitude of elevation in DHEA production by amnion was noted to be between 3.6- and 5.5-fold higher than the corresponding chorion. This study provides evidence that the fetal membranes possess 17-alpha hydroxylase and C-17, 20 lyase activities capable of synthesis of DHEA, an important androgen necessary for aromatization to estrogens in need by the developing fetus.

Amnion↗
PubMed1986

Causes of windowing-induced dysmorphogenesis (neural tube defects and early amnion deficit spectrum) in chicken embryos.

Previous reports suggest that windowing the shells of chicken eggs during the first day of incubation frequently results in dysmorphogenesis of the central nervous system. We report here data that further delineate the neural tube defects associated with this animal model. In addition, we describe another birth defect syndrome associated with windowing: the early amnion deficit spectrum (EADS). Several components of the egg are altered structurally by windowing: the shell, outer and inner shell membranes, yolk, and air space at the blunt end of the egg. A new air space is formed over the embryo as the original one at the blunt end is obliterated. A series of studies (pH, oxygen and carbon dioxide tensions, relative humidity, temperature, and deformation of the yolk documented with magnetic resonance imaging) examining individual steps of the windowing procedure and additional techniques that stimulate windowing suggest that mechanical stress causes isolated neural tube defects and dehydration causes amnion defects. These amnion defects are associated with other embryonic abnormalities suggestive of deformations consistent with EADS.

Amnion↗
PubMed1994

Domains of differential cell proliferation and formation of amnion folds in chick embryo ectoderm.

Patterns of cell proliferation in ectoderm epithelium that will form avian amnion correlate with morphogenesis, but not in an obvious pattern with respect to large-scale folding. At sites where the pre-axial amnion folds will first appear in 4- to 8-somite embryos, patterns of proliferation do not separate into domains that presage location of the single pre-axial fold that is commonly described in embryology texts. Instead, increased cell proliferation occurs in a significant, bilateral pattern. In stages with 13 to 27 somites, when lateral amnionic folds are prominent, five paraxial domains of cell proliferation correlate with morphology and show decreasing levels of cell proliferation with distance from the neural axis. Slowly growing areas surround rapidly growing areas and could assist buckling of epithelium by providing constraints on expansion of faster growing areas. Proliferation domains in ectoderm correlate with morphology and morphological events when localized changes in cell shape are lacking and suggest a role for differential cell proliferation in formation of large-scale epithelial folds in early chick embryos.

Amnion↗
PubMed2004

Proteomic determination of metabolic enzymes of the amnion cell: basis for a possible diagnostic tool?

Amniocentesis is a valuable and standard procedure for prenatal diagnosis of genetic or inborn errors of metabolism. Amnion cells are cultivated and chromosomes or proteins can be examined to provide molecular diagnosis. Mainly individual proteins are searched for based upon pedigrees and/or anamnesis. As inborn errors of metabolism involve a vast diversity of metabolic enzymes, we aimed to find a screening method for a large series of metabolic enzymes. Amnion cells were obtained from amniocentesis and subjected to proteomic analysis. We used two-dimensional gel electrophoresis with in-gel digestion followed by matrix-assisted laser desorption/ionization-time of flight analysis, to identify metabolic enzymes. Furthermore, we compared metabolic proteins in amnion cells from controls with those from Down Syndrome (DS). Enzymes involved in carbohydrate handling, amino acid handling, -purine metabolism and intermediary metabolism as well as miscellaneous metabolic pathways were detected. Protein levels of several enzymes were significantly deranged in samples obtained from patients with DS. This approach, with the advantage of the concomitant determination of many enzyme proteins, may form the basis for future metabolic screens when amniocentesis is carried out.

Amniocentesis↗
PubMed2006

Proteome analysis of human amnion and amniotic fluid by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Proteome analysis by 2-DE and PMF by MALDI-TOF MS was performed on human amnion and amniotic fluid at term. Ninety-two soluble and nineteen membrane proteins were identified from amnion. Thirty-five proteins were identified from amniotic fluid. Calgranulin A and B were found in all patients infected with Ureaplasma urealyticum, but not in any of the patients without infection, indicating that they are potential markers of intrauterine infection. Identity of calgranulin A and B was confirmed by MALDI-TOF/TOF MS. This study represents the first extensive analysis of the human amnion and amniotic fluid proteome at term and demonstrates that 2-DE and MALDI-TOF MS is a useful tool for identifying clinically significant biomarkers of problematic pregnancies.

Amino Acid Sequence↗
PubMed1985

Ectopia cordis thoracalis with craniofacial defects resulting from early amnion rupture.

A 33-week-gestation fetus was evaluated as having ectopia cordis thoracalis, midline sternal cleft, frontonasal dysgenesis, a midfacial cleft, and amniotic bands. Fibrous bands were attached to the apex of the heart, face, and the brain. There were no associated limb defects or scoliosis. The findings in this fetus and those in the literature suggest that acute amnion rupture in the third week of gestation may be the cause of these defects. Mechanical teratogenesis by tissue bands adherent to the heart may lead to ectopia cordis. The changes seen in the thorax, face, and brain suggest pressure necrosis, incomplete morphogenesis, tearing and tethering by amnion, and compression as a cause for these defects. A spectrum of defects is found following amnion rupture with the abnormalities being dependent upon the timing of the event. Ectopia cordis with amniotic bands appears to have an etiology distinct from isolated ectopia cordis. This suggests several different etiologies for ectopia cordis.

Abnormalities, Multiple↗
PubMed2006

Number of yolk sacs does not predict amnionicity in early first-trimester monochorionic multiple gestations.

OBJECTIVE: To determine the relationship between amnionicity and number of yolk sacs before 11 weeks of gestation. METHODS: Twenty-two cases of monochorionic multiple pregnancy were scanned before 11 weeks of gestation. There were 21 sets of twins and one of triplets. Amnionicity was determined by visualization of a dividing amniotic membrane between the gestational sacs. The number of yolk sacs was recorded and compared with the presence or absence of a dividing membrane for all fetuses. RESULTS: In 17/20 (85%) cases of monochorionic diamniotic twins, two yolk sacs were seen. In 3/20 (15%) cases of monochorionic diamniotic twins, a single yolk sac was seen. In the one case of monochorionic diamniotic triplets, two yolk sacs were visualized. In one case of monoamniotic twins, a single yolk sac was observed. CONCLUSIONS: In monochorionic pregnancies, the presence of two yolk sacs predicts diamnionicity. However, the use of the number of yolk sacs as a predictor of amnionicity may not be accurate in a small proportion of patients. The diagnosis of monoamnionicity can be made only following a careful search for a dividing amniotic membrane.

Amnion↗
PubMed1989

Expression of functional neurotransmitter receptors in an uninnervated tissue: avian amnion.

The smooth muscle of the avian amnion is unusual because it is normally never innervated. However, as assessed by contractile response, this tissue expressed at least 11 different types of receptor for neurotransmitter substances including acetylcholine, norepinephrine, histamine, 5-hydroxytryptamine, vasoactive intestinal peptide, urotensin II, neurotensin, and somatostatin-28. Three neurotransmitters, histamine, 5-hydroxytryptamine, and norepinephrine, each acted via 2 separate and antagonistic types of receptors. The amnion also responded to prostaglandin E2. On the other hand, the tissue did not respond to substance P or bradykinin, 2 peptides that are known to affect smooth muscle contractility in a variety of other systems. Studies with organ-cultured amnion demonstrated that the smooth muscle can be cultured early in development and will differentiate in vitro. Some, but not all, of the amniotic responses developed in a defined medium. The results indicate that this novel smooth muscle preparation will be useful for identifying epigenetic factors that control the expression of functional receptors.

Amnion↗
PubMed1989

The growth of human fibroblasts and A431 epidermoid carcinoma cells on gamma-irradiated human amnion collagen substrata.

Human fibroblasts and A431 human epidermoid carcinoma cells were cultured on gamma-irradiated human amnion collagen as well as on plastic dishes and non-irradiated collagen coated dishes. The morphology, attachment, growth and short-term cytotoxicity of these culture conditions have been determined. Both irradiated and non-irradiated amnion collagen enhanced the attachment and proliferation of fibroblasts as compared to the plastic dishes. No differences in these properties were observed for A431 cells cultured on irradiated collagen when compared with culture on non-irradiated collagen substrates. Cytotoxicity assays showed that irradiated and non-irradiated collagens were not cytotoxic for either fibroblasts or A431 cells. The results demonstrated that amnion collagen irradiated at doses of 0.25-2.0 Mrads is optimal for cell growth.

Amnion↗
PubMed2006

[Diseases of the adnexa in the tropics: amnion membrane transplantation for noninfectious trachoma-associated corneal ulcers].

BACKGROUND: Corneal ulcers with fornix shortening associated with late stages of cicatrizing trachoma contribute significantly to blindness in many developing countries. We report on the outcome of ocular surface and fornix reconstruction using amnion membrane transplantation. PATIENTS AND METHODS: From 2001 to 2005, cryopreserved human amnion membrane without mitomycin C was grafted to 25 eyes of 17 patients with trophic corneal ulcers and symblepharon (cicatrizing trachoma: 19 eyes of 14 patients, Stevens-Johnson syndrome: 4 eyes of 2 patients, alkali burns: 2 eyes of 1 patient) in a controlled case series. Follow-up was done up to 6 months. STATISTICS: Fischer's exact probability test. RESULTS: Of 25 eyes, 9 of 19 eyes with trachoma, 3 of 4 eyes with Stevens-Johnson syndrome, and 2 of 2 eyes with chemical burns showed complete reepithelialization and stromal recovery after 28-35 days (mean: 31+/-2.3 days). The primary success rate of trachoma eyes was not significantly different from the other indications (p=0.256). At 6 months post-op, 15 of 19 trachoma eyes (79%) compared to 2 of 6 non-trachoma eyes (33.3%) had developed a recurrence of symblephara (p=0.0592), and 13 of 15 eyes (86.6%) with a cicatricial trachoma compared to 1 of 6 with non-trachoma diagnosis experienced a recurrence of corneal vascularization (difference nonsignificant: p=0.1752). Persistent long-term reepithelialization was observed only in 1 of 19 trachoma eyes (5.3%) versus 4 of 6 non-trachoma eyes (66.7%, p=0.005); 3 of 19 trachoma eyes with a recurrence of ulcers had perforated after 6 months. CONCLUSIONS: Human amnion membrane without mitomycin C can be used for ocular surface reconstruction in selected patients with cicatrizing trachoma. Its efficacy in the long-term rehabilitation of cicatrizing trachoma seems to be limited due to the progressive scarring.

Adult↗
PubMed1977

Human amnion metabolism. I. In vitro maintenance.

The energy stores of human term amnion include glycogen (2.2 +/- 0.3 mumoles of glucose per gram, mean +/- S.E.) and ATP (0.13 +/- 0.2 MM.). Histologic structure and biochemical functions were preserved during incubations of amnion for 120 minutes at 37 degrees C. in a defined medium simulating amniotic fluid; glycogen concentrations were maintained at control values, and the concentration of ATP usually remained at 85 to 100 per cent of control values. Glucose utilization during the first 60 minutes of incubation was linear at a rate of 70.0 +/- 3.0 nmoles per minute per gram of tissue. It is concluded that amnion is a highly metabolically active tissue that can be maintained in a viable state in a suitable medium.

Adenosine Triphosphate↗
PubMed1988

Stretch-induced delivery is independent of the functional fetal role and dysfunction of the amnion and decidua: a morphologic and enzyme cytochemical study.

The role of the fetus, amnion, and decidua in stretch-induced delivery was studied in six normal pregnant women (group 1) and six in whom the fetuses had been dead in the uteri for more than a week (group 2). The cervices were distended by laminaria for 48 hours; this was followed by balloon inflation with traction. During the balloon application, regular uterine contractions were initiated and increased in all patients, with four patients in group 1 and five in group 2 aborting or being delivered within 24 hours. Light and electron microscopic studies of the amnion obtained during apparent uterine activity or after delivery revealed normal cell morphologic features in both groups although an increased fat deposition in cytoplasm was noted in group 2. Decidua parietalis exhibited normal cell morphologic features in both groups, and cytochemical demonstration of acid-phosphatase activity in decidual cells confirmed no leakage of the lysosomal enzyme into the cell cytoplasm. These findings indicate that stretch-induced delivery is initiated independent of the functional fetal role and without dysfunction of the amnion and decidua.

Amnion↗
PubMed1988

Characterization of prostaglandin production in amnion-derived WISH cells.

This study was undertaken to characterize prostaglandin production and its regulation in the human amnion-derived WISH cell line. Epidermal growth factor, tumor growth factor-alpha, tumor growth factor-beta, human interleukin-1, tumor necrosis factor, phorbol 12-myristate 13-acetate, phorbol 12,13-dibutyrate, 4 alpha-phorbol 12,13 didecanoate, and dexamethasone were tested for their ability to modulate prostaglandin production in WISH cells. Quantitatively, the major prostaglandin produced in WISH cells was prostaglandin E2. Treatment with epidermal growth factor, tumor growth factor-alpha, tumor necrosis factor, interleukin-1, phorbol 12,13-dibutyrate, and phorbol 12-myristate 13-acetate resulted in a concentration-dependent stimulation of WISH cell prostaglandin E2 production; tumor growth factor-beta and the inactive phorbol ester analog 4 alpha-phorbol 12,13 didecanoate had no effect. Dexamethasone treatment resulted in concentration-dependent inhibition of prostaglandin E2 production by WISH cells. WISH cells responded in a qualitatively similar manner to that previously observed in primary cultures of human amnion with the exception of the response to dexamethasone. On the basis of the findings of this investigation, we suggest that WISH cells may be a useful model for studying some but not all aspects of the regulation of arachidonic acid release and prostaglandin E2 formation in amnion. WISH cells may also be used to evaluate the mechanisms that link regulation of immune function and arachidonic acid metabolism.

Adjuvants, Immunologic↗
PubMed1989

CA 125 in the epithelium closely related to the embryonic ectoderm: the periderm and the amnion.

The amnion is believed to be derived from either cytotrophoblastic cells or embryonic ectoderm. However, it produces and secretes CA 125, which is considered a differentiation antigen of fetal coelomic epithelium derived from the mesoderm of germ cells. To verify this, the immunohistochemical localization of CA 125 in human fetal tissues (between 7 and 23 weeks of gestation) derived from the ectoderm, endoderm, or mesoderm, and in the fetal membranes and placenta was studied. Among the mesoderm-derived tissues, only the fetal coelomic epithelium-related tissues were positive for anti-CA 125 from 15 weeks of gestation. The endoderm-derived tissues did not react with anti-CA 125. However, among the ectoderm-derived tissues, only the periderm reacted with anti-CA 125 from 7 weeks until it sloughed from the stratum intermedium by 23 weeks of gestation. Among the fetal membranes and placenta, only the amnion reacted with anti-CA 125 from 9 weeks to term. These findings indicate that the amnion and the periderm, both of which constitute the epithelia covering the amniotic cavity, in addition to the fetal coelomic epithelium-related tissues, produce CA 125.

Amnion↗