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At least 667 records · Page 37Linked to original sources
PubMed1982

Metabolism of C19-delta 5-3 beta-hydroxysteroids in the term human amnion.

In human amniotic epithelium isolated from fetal membranes of 2 preterm and 14 full-term fetuses conversion of dehydroepiandrosterone (DHA) into 7-hydroxy-DHA and other highly polar metabolites, to 5-androstenediol and to a lesser extent into androstenedione and testosterone was observed. Similarly, 5-androstenediol was converted by the amniotic epithelium into DHA, highly polar metabolites and also, to a lesser extent, into testosterone and androstenedione. The conversion was higher (with the exception of androstenedione formation) in amnions from preterm deliveries than from the full-term pregnancies. There were no sexual differences. In comparison with the results of our previous study it may be suggested that the formation of delta 4-3-oxo metabolites (testosterone, androstenedione) is maximal in the first trimester, decreases in the second trimester and remains low in the third. In contrast, the oxidation of 5-androstenediol to DHA and the formation of highly polar metabolites is maximal at the end of the second and early in the third trimester and decreases as the delivery approaches.

Amnion↗
PubMed1980

Detection of type D retrovirus in a human amnion cell line (FL).

This paper describes the detection of viral particles in a human amnion cell line (FL). These particles belong to the group of type D retroviruses, because of their characteristic morphology, their major antigenic determinants, and the presence of particle-associated Mg++-preferring RNA-dependent DNA polymerase. In addition to budding and mature type D virus particles, intracytoplasmic type A structures have also been found. Immunological analysis provided evidence of cross-reactivity between the particles described and the Mason-Pfizer monkey virus as well as type D retroviruses from other human cell lines (PMF, HEp-2). Particles isolated from FL cell medium were shown to infect type D virus-susceptible human TU 197 cells.

Amnion↗
PubMed1980

[Clinical experience from transcervical intra-amnionic hypertonic saline instillation for termination of pregnancy in second trimester].

Transcervical intra-amnionic hypertonic saline instillation was used and tested for its practicability on pregnant women in the second trimester with contra-indications to prostaglandins. The pregnancies were terminated without any remarkable complication, under most stringent observation of aseptic conditions, careful cleaning of the birth canal, and preventive use of broad-range antibiotics. Immediate morbidity accounted for 4.35 per cent. Hence, the technique was not inferior to other approaches, when reference was made to negative outcome of termination. No late morbidity was recorded by clinical follow-up checks. Once the method will be verified by a higher number of patients and further improved, for example, by reducing the time required for induction, it may become a readily practicable and inexpensive variant of termination in the second trimester.

Abortion, Induced↗
PubMed1980

Sinusoidal fetal heart rate pattern in association with amnionitis.

A case is reported of intrapartum sinusoidal fetal heart rate (FHR) pattern in association with intrapartum amnionitis. Fetal and maternal outcome were excellent. Sinusoidal FHR patterns have been widely associated with severe fetal asphyxia and impending fetal death. In reviewing the published experience with sinusoidal FHR patterns, it is concluded that, although it is alarming, not every sinusoidal FHR pattern is an indication for immediated delivery.

Adult↗
PubMedDate not supplied

[The reaction of the chick embryo amnion to indolamines].

Studies have been made of the effect of serotonin and tryptamine on contractile activity of nerve-free smooth muscle strip from the amnion of 7-19-day chick embryos. It was shown that stimulatory effect of indolamines depends on the age of embryos. Within 7-9 days of incubation, there was a delay in the onset of the response, the sensitivity being rather low (threshold dose for serotonin-5 microM); prolonged washing before each application of the drugs was usually necessary. At the 13-15th day, the reaction-becomes rather quick, being easily abolished by washing procedure; the sensitivity and the level of maximum reaction increase (for serotonin, mean Kd and Pmax values were equal to 0.3 microM and 62.2 mg/mg tissue respectively). Developmental changes in responses to tryptamine are similar to those described for serotonin. The effectiveness of serotonin at the 7-9th day of incubation is significantly lower than that of Ach, whereas at the 13-15th day the value of Kd is similar to that for Ach, Pmax being often higher than for the latter. The data obtained are discussed in relation to proliferation changes in amniotic tissue.

Acetylcholine↗
PubMedDate not supplied

[The role of serotonin and noradrenaline in regulating the motor activity of the chick amnion].

In experiments on chick embryos from various age groups, studies have been made of the effect of a blockader of serotonin receptors--cyproheptadine--and blockader of adrenoreceptors--propranolol--on rhythmic activity of the amnion in vivo after injection of the substances into amniotic fluid. Stimulating effect of propranolol from the 9th to the 19th day of incubation and inhibitory effect of cyproheptadine from the 5th to the 19th day of incubation were revealed. These results indicate the existence of serotonin and noradrenaline in the amniotic fluid of chick embryo. High performance liquid chromatography directly confirmed this conclusion.

Amnion↗
PubMed1993

Accuracy of ultrasonographic criteria for the prenatal diagnosis of placental amnionicity and chorionicity in twin gestations.

A total of 31 twin pregnancies were studied antenatally with ultrasound, followed up clinically, and the placentas examined to determine if, solely on the basis of prenatal sonography, an accurate assessment of amnionicity and chorionicity could be made. Sonographic features noted included number of placental sites, fetal gender, qualitative and quantitative evaluation of the dividing membrane. Documentation of two placental sites or different fetal gender confirms the presence of a dichorionic-diamniotic pregnancy. When only one placental site or similar fetal gender is demonstrated, examination of the membrane is helpful for distinguishing between dichorionic and monochorionic diamniotic gestations. A thick membrane separating the fetuses was seen in all dichorionic diamniotic pregnancies. A thin membrane was visible in 94.4 per cent of monochorionic-diamniotic pregnancies. The predictive value of a thick membrane with regard to a dichorionic-diamniotic pregnancy was 92.3 per cent and the predictive value of a thin membrane with regard to a monochorionic-diamniotic pregnancy was 100 per cent. The thickness of the membrane was measured in 13 cases. With a thickness of 2 mm used as a cutoff point, the accuracy in predicting monochorionic or dichorionic twinning was 100 per cent for both. Lack of visualization of a separating membrane suggests a monochorionic-monoamniotic pregnancy.

Amnion↗
PubMed1993

The effect of vanadate of arachidonic acid metabolism in human amnion cells.

This investigation was designed to investigate the effects of vanadate on arachidonic acid metabolism in human amnion cell in primary monolayer culture that served as a model system. The secretion of prostaglandin E2 (PGE2) into the culture medium was quantified by radioimmunoassay. The rate of conversion of [14C] arachidonic acid to [14C] PGE2 (PGE2 synthase) was determined in cell sonicates under optimal in vitro conditions. A maximal stimulation of PGE2 production and PGE2 synthase activity was determined with vanadate at a concentration of 32 microM) was effective maximally after 4 h of treatment, i.e., the production of PGE2 was stimulated 2,3-fold, and the specific activity of PGE2 synthase 2,1-fold compared with control incubations, respectively. We suggest that vanadate acts to increase the rate of conversion of arachidonic acid to PGE2 by a mechanism that involves de novo protein synthesis or that alters the phosphorylation state of enzymes that are requisite for the conversion of arachidonic acid to PGE2.

Amnion↗
PubMed1993

Vanadate, epidermal growth factor and prostaglandin E2 production in human amnion cells.

We have investigated the effects of vanadate (VAN) and mouse epidermal growth factor (mEGF) on prostaglandin (PG) E2 production in human amnion cells in monolayer culture that served as a model system. The secretion of PGE2 into the culture medium was quantified by radioimmunoassay. The rate of conversion of [14C] arachidonic acid to [14C] PGE2 (PGE2 synthase) was determined in cell sonicates under optimal in vitro conditions. After a treatment period of 4 h we observed an increase in PGE2 production in the presence of mEGF (4.7-fold), VAN (1.8-fold) or both agents (6.8-fold) over control samples. Similarly, the specific activity of PGE2 synthase was stimulated maximally after 4 h with mEGF (2.1-fold), VAN (1.7-fold) or with both (4.8-fold) compared with untreated tissue samples. In the presence of cycloheximide those effects were abolished. We suggest, that VAN and mEGF act by a mechanism(s) that involves de novo protein synthesis or that alters the phosphorylation state of enzymes that are requisite for the conversion of arachidonic acid to PGE2.

Amnion↗
PubMedDate not supplied

Comparative studies of Ca N-acetylhomotaurinate and Ca N-acetyltaurinate. II. Preventive and opposing actions of the acute ethanol depletive effect on the ionic transfer through the isolated human amnion.

Ethanol reduces the ionic paraplacental transfer through the human amnion. This effect is exerted on the cationic paracellular pathway, the coupling between two adjacent epithelial cells, the monovalent cation pump and the antiport system. In this study, the preventive and opposing actions of two taurine and homotaurine derivatives (Ca N-acetyltaurinate: ATACa, Ca N-acetylhomotaurinate: AOTACa) were observed. One the maternal side, ATACa and AOTACa demonstrated protective actions on cationic paracellular pathways and on the Na/K-ATPase pump with AOTACa only. On the fetal side, the effect of ATACa was limited to the sodium paracellular pathway. This effect was total at 5 mM. On the maternal side, ATACa and AOTACa exhibited an opposing action on the same components of the conductance. But on the fetal side, ATACa increased the ethanol effect and AOTACa exerted an antagonistic effect on the cation pump only. These results indicate that two closely related molecules may have different effects on a membranous ethanol model.

Acamprosate↗
PubMedDate not supplied

[The modifying action of a complex of physiologically active substances isolated from the human amnion on chromosome damage].

It was determined that the complex of physiological active substances separated from human amnion reduced the frequency of the hepatocytes with chromosomal aberrations in rats. This reduction of chromosomal damages was noted at spontaneous and induced mutagenesis. The value of cytogenetical effect, the availability of raw material and the natural origin of the drug allow to propose it for further study and use as modifier of mutagenic action.

Amnion↗
PubMed1977

Unrecognized amnionitis and prematurity: a preliminary report.

Quantitative amniotic fluid cultures were performed on 12 patients delivered of premature infants (10-premature labor, 2-premature rupture of membranes). Specimens from patients in premature labor were obtained at the time of amniotomy via transcervical needle aspiration or intrauterine catheter. Of the seven patients with colony counts greater than 1,000 per ml, two mothers and four neonates had clinical evidence of infection. Blood cultures from two infants and one mother and cerebrospinal fluid cultures from one newborn infant were positive for the same organism isolated from amniotic fluid. Anearobic bacteria were the predominant isolates in four specimens and included Bacteriodes species in two. In contrast, the five mothers and infants associated with counts of less than 1,000 per ml exhibited no infectious morbidity. Three had no bacterial growth from amniotic fluid, and factors commonly associated with prematurity were recognized in four. These clinical and microbiologic observations suggest that current methods of evaluating patients with premature labor and delivery are incomplete, and the role of unrecognized amnionitis should be reevaluated.

Amnion↗
PubMed1997

Induction of prostaglandin H synthase-2 and tumor necrosis factor-alpha in human amnionic WISH cells by various stimuli occurs through distinct intracellular mechanisms.

These studies examined the signal transduction mechanisms by which prostaglandin (PG) E2 production can occur in human amnionic WISH cells in response to the stimuli okadaic acid, interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, phorbol-12-myristate-13-acetate (PMA) or combinations of PMA with IL-1beta or TNF-alpha. We also investigated whether WISH cells are capable of producing TNF-alpha or IL-1beta in response to stimulation, because these cytokines can be produced in an autocrine fashion to perpetuate an inflammatory response. Our data indicate that the magnitude of PGE2 production induced by a given stimulus correlated temporally with the level of PGH synthase-2 (PGHS-2) protein. PMA or IL-1beta induced PGE2 production 2 to 4 hr after treatment, whereas the combination of these agents produced the most rapid induction 2 hr after treatment. Only okadaic acid induced the production of both PGE2 and TNF-alpha, after a lag of 12 to 18 hr. PGE2 production by all stimuli was inhibited by dexamethasone, the IL-1 receptor antagonist (IL-1ra), the specific PGHS-2 inhibitor NS-398 and the protein kinase inhibitor staurosporin. In contrast, TNF-alpha production in response to okadaic acid was inhibited by the TNF-converting enzyme inhibitor GI 129471 and staurosporin but was unaffected by either IL-1ra, dexamethasone or NS-398. We conclude that WISH cells are capable of producing bioactive proinflammatory mediators such as TNF-alpha and PGE2 through separable intracellular signal transduction mechanisms. The ability of IL-1ra to reduce PGE2 production caused by all stimuli used suggests an autocrine role for IL-1 in PGHS-2 induction in these cells.

Amnion↗
PubMed1977

Replacement of the peritoneum with amnion following pelvic exenteration.

An analysis was made of 24 patients undergoing pelvic exenteration. By chance, the patients are divided into two groups, 12 having the pelvic floor treated by the traditional means and 12 in whom amniotic membranes have been used. A statistically significant shortening of the hospital stay was experienced by those in the amnion group with a total lack of intestinal complications being related to the raw surface of the pelvis. A large number of recurrent or de novo carcinomas of the vagina following carcinoma of the cervix treated with radiation are identified. Two deaths in this series were related to complications of the small intestine.

Aged↗
PubMed1996

[Establishment of human amnion cell mutagenesis system by using a shuttle vector pS189].

Using transient shuttle vector pS189, we established a subclone human amnion cell (FL) mutagenesis detection system, and we detected the mutation specificity of N-methy-N'-nitro-N-nitrosoguanidine (MNNG) in this system. The spontaneous mutant frequency of target gene supF was 1.7 x 10(-5) and MNNG-induced mutant frequency was increased with dosage. The results from 0.8% agarose gel electrophoresis, PCR, PCR-single strand conformation polymorphism (PCR-SSCP) analysis showed that MNNG-induced 89% mutants were point mutants. These results indicated that this system can be used to detect and study the mutagenesis mechanism of potential mutagens.

Amnion↗
PubMed1988

Epidemiology of the early amnion rupture spectrum of defects.

We used data from the population-based Metropolitan Atlanta Congenital Defects Program to study the epidemiology of the early amnion rupture spectrum of defects. For the period 1968 through 1982, we identified 45 patients among 388,325 live births, for a birth prevalence rate of 1.16 per 10,000. The prevalence for male infants was 0.91 and for female infants, 1.44. The defects occurred 1.76 times more often in blacks than in whites (95% confidence interval 0.98, 3.13). Infants of young, black multigravidas (less than 20 years, more than one pregnancy) showed the highest rate (6.2), and infants of older, black multigravidas showed the lowest rate (0.5) (rate ratio = 12.4, 95% confidence interval 4.2, 36.4). These findings suggest that young, black multigravidas are at much higher risk than are older, black multigravidas of having infants with this spectrum of defects. Ascertainment (diagnostic) differences between hospitals probably account for some of the racial discrepancy in birth prevalence, but they do not explain the maternal age effects in black multigravidas. Because the higher rates for blacks probably reflect more accurate diagnoses, the findings also suggest that a closer estimate of the true birth prevalence may be about 3 per 10,000 live births.

Amniotic Band Syndrome↗
PubMed1977

Identification of a bactericidal factor (B-lysin) in amnionic fluid at 14 and 40 weeks' gestation.

Amnionic fluid (AF) specimens from 40 normal obstetric patients at 14 to 16 weeks' gestation and at 37 to 40 weeks' gestation were found to contain both lysozyme and a bactericidal substance identified as B-lysin. The concentrations of both lysozyme and B-lysin were significantly higher in the AF at 40 weeks' than at 14 weeks' gestation. B-lysin concentration in AF were also found to be significantly higher than in either cord or maternal blood.

Amniotic Fluid↗