Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “AMNIOTIC FLUID”

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 361 records · Page 20Linked to original sources
PubMed1986

Assessment of the AmnioStat-FLM immunoagglutination test for phosphatidylglycerol in amniotic fluid.

One hundred and eight amniotic fluids were assayed by the AmnioStat-FLM (A-FLM) immunological agglutination test for phosphatidylglycerol (PG) and simultaneously measured enzymatically for PG content. Of 52 amniotic fluids found to be PG negative by the A-FLM method, all had enzymatic PG concentrations less than or equal to 1.5 mumol/l. Conversely, of 56 amniotic fluids judged to be either PG positive or weak positive, all but five had enzymatic PG concentrations greater than 1.5 mumol/l. The sensitivity of the A-FLM assay employed clinically for predicting foetal lung maturity was 89% and the specificity was 100%. The overall predictive accuracy of the test could be improved by providing controls at lower, more appropriate PG concentrations. Ninety-one fluids analysed by the A-FLM kit were subsequently tested for the presence of PG by two-dimensional thin-layer chromatography (2D TLC). A 94%-concordance between the methods was found.

Agglutination Tests↗
PubMed1980

Capillary method for assessment of pulmonary maturity in utero with the use of amniotic fluid.

Eighty-one human amniotic fluid samples of assessment of pulmonary maturity in utero have been studied by means of the capillary method, a simple and rapid test that correlates with the shake test and L/S ratio. With the advancement of gestational age the flow rate of amniotic fluid decreases on cellulose filter paper (Whatman) in the capillary pasteur pipette. Retention time for 20 microliter amniotic fluid of 74 +/- seconds correlates well with the positive shake test and with L/S ratio of 2.0 or greater in normal human pregnancies.

Amniotic Fluid↗
PubMed1990

[Effects of amalgam fillings on the mercury concentrations in amniotic fluid and breast milk].

Human amniotic fluid was gained from 95 pregnant women by amniocentesis (group 1) and from 20 women during delivery (group 2). The concentrations of inorganic mercury in amniotic fluid as assessed directly by cold-vapor atomic absorption spectrophotometry (CV-AAS) averaged 0.29 +/- 0.1 microgram/l in group 1 and 0.86 +/- 0.25 microgram/l in group 2. Surface areas of dental amalgam fillings were also estimated in these women and ranged between 0 and 930 mm2. There was no correlation between the surface area of maternal amalgam fillings and the concentrations of inorganic mercury in amniotic fluid (r = -0.122 and -0.069, respectively). Furthermore, no positive correlation existed between amalgam fillings and the concentration of total mercury in maternal blood (4.48 +/- 2.33 micrograms/l) and in neonatal blood (3.28 +/- 1.57 micrograms/l) as measured by CV-AAS in group 2 (r = -0.4 and -0.12, respectively). Concentrations of total mercury were also measured by CV-AAS in the breast milk of 86 women, five to ten days after delivery. These concentrations averaged 1.9 +/- 1.6 micrograms/l and were also not significantly correlated to the maternal amalgam surface areas (r = 0.188). In conclusion, maternal amalgam fillings are of no importance for the mercury load of the fetus and the neonate.

Adolescent↗
PubMed1977

Decidua: a possible source of amniotic fluid prolactin.

The source of amniotic fluid prolactin was investigated with the use of amnion, chorion, placenta, and decidual tissue taken from term human pregnancy. Decidua alone of these tissues contained significant quantities of prolactin. The release of decidual prolactin was affected by the presence or absence of oxygen and protein, and the amount of prolactin released far exceeded the decrease in tissue content during incubation. It is concluded that: (1) decidua may be a major source of amniotic fluid prolactin, (2) synthesis of prolactin occurs during incubation of decidua, and (3) sufficient prolactin is present in the decidua to account for that found in amniotic fluid at term.

Amnion↗
PubMed1995

Blockade of digestion by famotidine pretreatment does not interfere with the opioid-enhancing effect of ingested amniotic fluid.

Ingestion of placenta or amniotic fluid by rats has been shown to enhance ongoing opioid-mediated antinociception, but does not, by itself, produce antinociception. This enhancement is produced by an active substance(s) in placenta and amniotic fluid that we have termed POEF for placental opioid-enhancing factor. Previous research has shown that enhancement requires mediation by the gastrointestinal system: gastric vagotomy blocks enhancement produced by ingested placenta; amniotic fluid injected SC or IP does not produce enhancement. The present study was designed to distinguish between two possible explanations for the blockade of the POEF effect produced by gastric vagotomy: that afferent information arising in vagal gastric receptors conveys the critical information to the CNS, or that disruption of vagal efferent action on digestion blocks the manufacture or activation of the POEF molecule in the gut. Famotidine is an H2-histamine receptor antagonist that reduces gastric acid and pepsin secretion to an extent at least as great as gastric vagotomy. Rats treated with either famotidine or a vehicle were fed placenta or a control substance, then stimulated with vaginal/cervical probing to produce antinociception that is partly opioid mediated. Famotidine did not block POEF enhancement of vaginal/cervical stimulation-induced analgesia in a tail flick latency test. These results suggest that enhancement by POEF does not require normal digestive processes or other processes inhibited by famotidine.

Amniotic Fluid↗
PubMed1984

Stimulation of prostaglandin E2 synthesis in human amnion cells maintained in monolayer culture by a substance(s) in amniotic fluid.

A substance(s) in amniotic fluid of human pregnancies promotes a striking increase in prostaglandin E2 production in human amnion cells maintained in primary monolayer culture. The prostaglandin E2 synthesis-stimulatory factor(s) acts in a time- and dose-dependent manner to accelerate prostaglandin E2 formation. We suggest that a substance of fetal origin enters amniotic fluid by way of fetal urine and acts to regulate prostaglandin E2 synthesis in amnion. Such a process may be of fundamental importance in the regulation of amniotic fluid volume homeostasis and in the initiation of parturition.

Amnion↗
PubMed1996

[Collagen degradation products in amniotic fluid].

It was found that amniotic fluid (38-42 Hbd) contains hydroxyproline in concentration about 10 micrograms/ml. Gel filtration and dialysis demonstrated that most of hydroxyproline exists in a form of low molecular weight products. Furthermore, it was found that amniotic fluid contains a protein which eluates during gel filtration in void volume of the column. It gives a positive reaction for hydroxyproline but the absorption spectrum of such product is not characteristic for this amino acid. Furthermore, it is not digested by bacterial collagenase. It allows to conclude that amniotic fluid (38-42 Hbd) does not contain collagenous proteins. Only low molecular weight degradation products were found. Only part of them is susceptible on the action of bacterial collagenase.

Amniotic Fluid↗
PubMed2005

Non protein bound iron concentrations in amniotic fluid.

OBJECTIVES: To investigate whether amniotic fluid concentrations of non protein bound iron (NPBI) vary with growth in healthy fetuses and also offer a reference curve in the second trimester of pregnancy. DESIGN AND METHODS: Amniotic fluid concentrations of NPBI were measured by HPLC in 118 women with physiological singleton pregnancies, who underwent amniocentesis for fetal karyotype between weeks 15 and 18 of gestation. RESULTS: NPBI increased progressively from weeks 14--15 to weeks 15--16, peaking at 17--18 weeks of gestation. NPBI values regressed positively with gestational age (GA). Multiple linear regression analysis between NPBI, as dependent variable, and various fetal parameters, as independent variables, showed a statistically significant regression coefficient with GA, bi-parietal diameter and transverse cerebellar diameter. CONCLUSIONS: The present data constitutes the first quantification of NPBI concentrations in amniotic fluid under physiological conditions. Correlations with GA and ultrasound fetal biometry suggest that NPBI may play a role in fetal growth.

Adult↗
PubMed1987

Amniotic fluid propionylcarnitine in methylmalonic aciduria.

Amniotic fluid samples from pregnancies complicated by foetal methylmalonic aciduria and from metabolically normal pregnancies were obtained at 16-18 weeks of gestation and analysed for total, free and acylcarnitine and individual carnitine esters. The amniotic fluid concentrations of total acylcarnitine and propionylcarnitine were higher in pregnancies with higher in pregnancies with methylmalonic aciduria than in normal pregnancies. The predominant carnitine ester was propionylcarnitine in the methylmalonic aciduria group and acetylcarnitine in the normal group. These findings suggest that in methylmalonic aciduria, abnormalities of carnitine metabolism already occur early in gestation. The amount of propionylcarnitine in amniotic fluid may be useful as an additional indicator of foetal methylmalonic aciduria.

Acetylcarnitine↗
PubMed1976

Amniotic fluid testosterone levels in midpregnancy.

Amniotic fluid testosterone levels were measured on specimens obtained between 12 and 25 weeks' gestation from 58 male-fetus and 77 female-fetus pregnancies. For the male fetuses the mean +/- SE amniotic fluid testosterone level of 223 +/- 10 pg/ml was significantly higher (P less than 0.001) than the concentration found for the female fetuses (40 +/- 2 pg/ml). The ranges were 104-424 and 18-82 pg/ml, respectively, for the same fetuses. In the male fetuses the highest mean level was found during the 17th gestational week, but the mean level observed during any 1 week was not significantly differenf from any other week for both sexes. These data are consistent with the concept that amniotic fluid testosterone levels may be a rapid and effective method for establishing fetal sex in utero during midgestation.

Amniotic Fluid↗
PubMed1994

Maternal contamination of amniotic fluid demonstrated by DNA analysis.

DNA from 16 sets of samples comprising DNA from uncultured amniotic fluid cells, cultured amniotic fluid cells, fetal tissue, and maternal blood was analysed by the polymerase chain reaction (PCR) with AC-repeat primers. The analysis was performed to investigate the presence of contaminating maternal cells in amniotic fluid which would affect the reliability of DNA studies for prenatal diagnosis. In three sets, maternal contamination of uncultured amniotic fluid cells was detected. In one of the three sets, maternal contamination was present in both uncultured and cultured amniotic fluid cells. The use of amniotic fluid cells as a source of DNA for prenatal diagnosis should be limited to cases where the purity of the DNA can be demonstrated prior to the diagnostic test being performed. This limitation in the use of amniotic fluid DNA also extends to other forms of diagnosis relying on the purity of amniotic fluid samples, particularly the new in situ hybridization methods currently being developed.

Amniotic Fluid↗
PubMed1984

Effect of blood contamination on lecithin to sphingomyelin ratio in amniotic fluid by different detection methods.

Amniotic phospholipid detection methods such as cupric acetate measure unsaturated lecithin whereas others such as phosphomolybdate detect both unsaturated and saturated lecithin. Because of the extreme unsaturation in serum and red blood cell lecithin, we compared lecithin (L) and sphingomyelin (S) content of maternal blood as well as the effect of blood contamination on amniotic fluid L/S ratios. L/S ratios were obtained by thin-layer chromatography utilizing both cupric acetate and phosphomolybdate for phospholipid detection. The L/S value (mean +/- SD) of maternal serum obtained by cupric acetate was 1.90 +/- 0.19 and that for phosphomolybdate 1.78 +/- 0.17. The results of increasing serum concentrations in amniotic fluid prior to analysis suggest that as little as 0.5% contamination alter results and by 2% contamination values approach the L/S ratio of actual serum whether the amniotic fluid was initially mature or immature by either method. The serum L/S ratio by cupric acetate equaled its maturity threshold of 2.0 while the serum L/S ratio by phosphomolybdate was below its threshold of 3.0. Whereas both methods would have falsely immature values in the presence of blood only phosphomolybdate would assure against false maturity.

Amniotic Fluid↗
PubMed1979

Amniotic fluid embolism.

The statement that amniotic fluid embolism is the most dangerous and untreatable condition in obstetrics appears to be true. It must be suspected in any patient who collapses or bleeds excessively during labour or the immediate post-partum period. Attempts should be made to secure a definitive diagnosis in life by examination of blood obtained from the right side of the heart and the sputum for elements of amniotic fluid. Lung scanning is a useful aid to diagnosis. The principal factors that have been implicated in the clinical syndrome of amniotic fluid embolism are anaphylaxis, vascular obstruction by particulate matter, vascular spasm due to prostaglandins and possibly some other vasoactive substances, and the possibility that all the changes could be explained by disseminated intravascular coagulation as a primary event. Further work is required to elucidate the relative contributions of these various factors. Due to the suddeness of the catastrophe and the very high mortality, haemodynamic data in humans is virtually non-existent. With improved methods of resuscitation it is to be hoped that the mortality rate will be reduced and that such data will become available. In this way it might become possible to apply the results of animal research and indicate the most effective method of treatment.

Adolescent↗
PubMed2000

Interaction between pulmonary surfactant and vernix: a potential mechanism for induction of amniotic fluid turbidity.

The development of amniotic fluid turbidity during the third trimester is a known marker of fetal lung maturity. We hypothesized that this turbidity results from detachment of vernix caseosa from the fetal skin secondary to interaction with pulmonary-derived phospholipids in the amniotic fluid. To test this hypothesis, we exposed vernix to bovine-derived pulmonary surfactant over a physiologically relevant concentration range. Ten milligrams of vernix was evenly applied to the interior walls of 1.5-mL polypropylene microfuge tubes. Surfactant phospholipids were added to the tubes followed by slow rotation at 37 degrees C overnight. The liquid was decanted and spectrophotometrically analyzed at 650 nm to detect solution turbidity due to vernix detachment and/or emulsification. Increasing concentrations of surfactant phospholipids produced a dose-dependent increase in solution turbidity. A phospholipid mixture closely approximating natural pulmonary surfactant but devoid of surfactant-associated proteins yielded no increase. In other studies, the flow properties of vernix were studied in a Haake flow rheometer at 23 degrees C and 37 degrees C. There was a marked temperature-dependent effect with lower stress required to elicit flow at 37 degrees C compared with 23 degrees C. This temperature dependence was also demonstrated in the turbidity assay with a 124% increase in turbidity at body temperature compared with room temperature. We conclude that under in vitro conditions, pulmonary surfactant interacts with vernix resulting in detachment from a solid phase support. We speculate that in utero, this phenomenon contributes to the increase in amniotic fluid turbidity that is observed near term.

Amniotic Fluid↗
PubMed1989

Immunoreactive human epidermal growth factor concentrations in amniotic fluid, umbilical artery and vein serum, and placenta in full-term and preterm infants.

Immunoreactive human epidermal growth factor (IR-hEGF) was measured in samples taken from 27 full-term and 14 preterm infants. The samples included amniotic fluid, amniotic membranes, fetal and maternal sides of the placenta, and matched umbilical artery and umbilical vein serum. Our results demonstrated the presence of IR-hEGF in the human placenta, amniotic fluid and cord blood during the second half of gestation. The increase in placental tissue, amniotic fluid, and cord blood concentration with progressive gestation suggests a possible functional role for EGF during perinatal development.

Amniotic Fluid↗
PubMed1983

A controlled study of genital mycoplasmas in amniotic fluid from patients with intra-amniotic infection.

Amniotic fluid (AF) was collected via a transcervical, intrauterine catheter from 52 patients with clinical intra-amniotic infection (IAI) and from 52 matched, uninfected controls. The AF was cultured for Mycoplasma hominis and Ureaplasma urealyticum as well as for aerobic and anaerobic bacteria. Eighteen (35%) patients with IAI and four (8%) controls had M. hominis in AF (P less than 0.001). Twenty-six (50%) patients with IAI and 26 (50%) control patients had U. urealyticum in AF (difference not significant). In the AF specimens of patients with IAI, 15 (83%) of the 18 with M. hominis also contained greater than or equal to 10(2) colony-forming units (cfu) of a high-virulence bacterial isolate/ml (P less than 0.05). Within the limitations of the experimental design, U. urealyticum in AF is not associated with clinical IAI, whereas, with qualitative cultures, M. hominis in AF is. However, in IAI, M. hominis is isolated most commonly from the AF of patients with greater than or equal to 10(2) cfu of a high-virulence bacterial isolate/ml.

Amniotic Fluid↗
PubMed1981

Glial and neuronal cells in amniotic fluid of anencephalic pregnancies.

Cultured amniotic fluid cells from four anencephalic pregnancies were characterized in indirect immunofluorescence (IIF) microscopy using specific antibodies against different types of cytoskeletal intermediate filaments. Most of the cells showed a fine fibrillar cytoplasmic fluorescence with antibodies against glial fibrillary acidic protein (GFA), indicating that amniotic fluid cells in anencephalic pregnancies are of glial origin. The GFA-positive cells were rapidly adhering and proliferating. They remained as the major cell type also in long term cultures, and could easily be recovered from liquid nitrogen without losing their GFA positivity. GFA-positive cells were pleomorphic in appearance, and occurred in several morphologically different shapes. Amniotic fluid from one of the anencephalic cases contained typical neuronal cells, which in IIF were GFA-negative but could specifically be stained with anti-neurofilament antibodies. Most of the GFA-negative cells in all the cases were fibroblasts, identified by their fluorescence only with antibodies against vimentin. Epithelial cells showing positive keratin-fluorescence in IIF, were seen only occasionally.

Adult↗
PubMed1981

The stability of phospholipids in amniotic fluid.

A systematic study of amniotic fluid phospholipids including phosphatidylcholine (PC, lecithin), saturated phosphatidylcholine, and phosphatidylglycerol was undertaken to evaluate the stability of these surfactant indices as a function of temperature and time. The purpose of the study was to determine optimum conditions for storage and for transport of specimens to centralized laboratories performing comprehensive analyses of amniotic fluid phospholipids for improved assessment of fetal lung development. Remarkable stability was found for the above phospholipids, as well as for the more commonly employed ratio of lecithin to sphingomyelin. We determined that room temperature more commonly employed ratio of lecithin to sphingomyelin. We determined that room temperature storage is acceptable for periods up to 24 hours; however, when longer delays before lipid extraction are anticipated, it is essential that specimens be frozen or that refrigeration or wet-ice storage (4 degrees C) be employed. Results of this study indicate that when amniotic fluid samples are stored frozen and strict quality control is maintained in analytic procedures, only minimal changes occur in phospholipid concentrations over 12 months.

Amniotic Fluid↗