Immunosuppressive activity of mouse amniotic fluid

Immunosuppressive activity of mouse amniotic fluid was investigated. Swiss mice were treated from birth through young adulthood with intraperitoneal injections of homologous mouse amniotic fluid. A marked suppression of the primary splenic plaque-forming cells antibody response to sheep red blood cells was demonstrated. A pronounced suppressive effect by amniotic fluid was noted on the gamma A and gamma G plaque-forming cells, with variable degrees of immunosuppression observed on the gamma M response. It is postulated that the immunosuppressive effect of amniotic fluid may be related to its alpha-fetoprotein content.     

Newly developed mecometer method for objective assessment of meconium content

We developed a new method for an objective assessment of the meconium content in amniotic fluid. By establishing a standard scale through a serial dilution of a known amount of meconium into the amniotic fluid, we developed a new method "mecometer" that can objectively measure the meconium content in meconium-stained amniotic fluid samples. The objectivity and reliability of this mecometer were verified by 300 student volunteers. At least 70% of the volunteers could objectively measure and digitally describe the meconium content in meconium-stained amniotic fluid samples. We believe our newly developed mecometer is a very simple, reliable, and portable method, not requiring any instruments.     

In-vivo study of diazepam transfer across the first trimester human placenta

Diazepam transfer by the first trimester human placenta wasinvestigated at pregnancy termination between 6 and 12 weeksof gestation. Fetal fluid samples were obtained from the exocoelomicand amniotic cavities of 65 pregnancies between 8 and 25 minfollowing the i.v. administration of 0.1 mg/kg diazepam to themother. Diazepam was detected in one-third of coelomic fluidsamples and two-thirds of amniotic fluid samples. Maternal serumand urine diazepam concentrations correlated negatively andpositively respectively, with time from drug injection to sampling.Individual diazepam concentrations were low on the fetal side,and the corresponding concentrations were independent of maternalserum concentrations and the time from drug injection to sampling.Amniotic fluid diazepam content increased significantly withadvancing gestational age. A multiple regression analysis showedthat the diazepam content of the coelomic fluid was not influencedby maternal serum diazepam concentration, the time from druginjection to sampling or gestational age, whereas only gestationalage contributed to the diazepam content of amniotic fluid. Thesedata demonstrate that the placental transfer of diazepam occursfrom week 6 of gestation, indicate a preferential transfer ofthis drug to the amniotic cavity and suggest that diazepam mayaccumulate in fetal circulation and tissues during organo-genesis.     

Mid-trimester diagnosis of bladder neck obstruction by ultrasound and paracentesis.

A bladder neck obstruction was suspected after ultrasound investigation at 16 weeks' gestation. Evaluation of protein content in the amniotic fluid, fetal ascites, and fluid from the overdistended bladder supported the diagnosis. Bladder outflow obstruction in the second trimester of pregnancy was not associated with raised alphafetoprotein levels in the amniotic fluid and maternal serum.     

Possibility of culturing foetal cells at early stages of pregnancy

The results of cell culture from amniotic fluid, obtained by amniocentesis, for the purpose of prenatal genetic diagnosis, are evaluated in relation to gestational age and quantity of cells available.
It is concluded that amniotic fluid from the first trimester of pregnancy is not suitable for cell culture purposes because of a scanty fluid volume and a low cellular content.     

产前诊断中羊水嵌合体形成机制的探讨

目的探讨产前诊断中羊水嵌合体形成的机制,便于临床医生在遗传咨询中正确处理羊水培养中出现的嵌合现象。方法 2004年1月至2010年4月对在中山大学附属第一医院胎儿医学中心因各种产前诊断指征就诊的患者行羊膜腔穿刺术取羊水做染色体检查,从中选取羊水染色体为嵌合体的患者穿刺脐血复查染色体,结合两者的结果探讨羊水嵌合体形成机制。结果羊水嵌合体检出33例,其中25例为假嵌合体,8例为真嵌合体,7例真嵌合体羊水结果与脐血结果一致,1例真嵌合体两者结果不一致。结论正确判断羊水培养中出现的真假嵌合体及其风险,对产前诊断和遗传咨询具有重要的意义。     

Amniotic fluid elicits appetitive responses in human newborns: Fatty acids and appetitive responses

In humans, maternal cues guide newborns to the maternal breast, and transitional cues may be present in maternal–fetal fluids. The aim of the present study was to determine the consistent presence of sensorial cues in three maternal–fetal fluids—amniotic fluid, colostrum, and milk—and test the ability of these cues to produce appetitive responses in newborns. In the analytical study, gas chromatography‐mass spectrometry (GC‐MS) detected eight fatty acids consistently present in the amniotic fluid, colostrum, and milk from 12 healthy volunteers, but we do not find a mammalian pheromone, identified in another mammalian species (rabbits), in another 30 volunteers. In the behavioral study, we explored the ability of amniotic fluid or its fatty acids to produce appetitive responses in 19 human newborns <24 hr after birth. Exposure to swabs impregnated with amniotic fluid or an artificial fatty acid mixture produced a longer duration of facial reactions that suggested appetitive (sucking) movements compared with respective vehicles (i.e., propylene glycol or centrifuged amniotic fluid with a low fatty acid content verified by GC‐MS). We conclude that the fatty acids contained in amniotic fluid may constitute a transitional sensorial cue that guides newborns to the maternal breast. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 221–231, 2013     

Prenatal diagnosis of Gaucher disease Assay of the ß-glucosidase activity in amniotic fluid cells cultivated in two laboratories with different cultivation conditions

Sixteen pregnancies at risk for Gaucher disease - six with the Norrbottnian form, one with a juvenile form with a similar clinical course to the patients from Norrbotten and nine with the infantile form - have been monitored by the assay of β-glucosidase activity in cultivated amniotic fluid cells with natural labelled glycosylceramide as substrate. Two methods of cultivation were compared in respect of their effect on the activity of lysosomal enzymes. No significant difference was found between the two marker enzymes, β-galactosidase and N -acetyl-β-glucosaminidase, but the β-glucosidase activity was significantly higher in the cells cultivated with one of the methods. In four of the pregnancies at risk, the β-glucosidase activity in the cultivated amniotic fluid cells was less than 5 % of that in the two control materials. These fetuses were regarded as affected with Gaucher disease and were aborted. Differentiation between controls and Gaucher heterozygotes was not possible in cultivated amniotic fluid cells. The diagnosis of Gaucher disease in the amniotic fluid cells was confirmed in three of the four cases by the assay of the β-glucosidase activity in the liver and brain of the aborted fetuses. The glucosylceramide content of the liver from two aborted fetuses was not augmented. The β-glucosidase activity was examined in seven placentas from pregnancies at risk for Gaucher disease and found to be in agreement with that in the cultivated amniotic fluid cells.     

Amniotic fluid macrophages and the antenatal diagnosis of anencephaly and spina bifida.

The macrophage content of amniotic fluid has been measured and the upper limit of normal on an arbitrary scale is 41. Amongst 65 amniotic fluids collected for antenatal diagnostic studies before 22weeks' gestation there were eight which had macrophage counts ranging from 82 to 6226,three of these were shown to have anencephaly and two spina bifida. The reasons for three apparently false positives are as yet undetermined. Rhesus iso-immunized amniotic fluids were found to have macrophage counts of up to 276 and a possible explanation for this is considered. It is argued that an elevated aminotic fluid macrophage count may indicate a CNS defect or possibly other fetal abnormality.     

提高羊水细胞培养成功率的方法

目的提高羊水培养的成功率。方法正常羊水保留换液标本,以备复查;异常羊水采用细胞分离技术提取羊水中的有效细胞成分;及时发现污染羊水并进行抗菌处理。结果提高了羊水培养的成功率（99.4%）并缩短异常羊水的培养时间,解决了部分污染羊水的污染问题（2/3）。结论保留换液标本可有效解决因收集不当而导致无法诊断的问题;细胞分离技术可提高异常羊水细胞培养的成功率并缩短培养时间,污染的羊水也可抗菌后培养成功。     

羊水偏少与围产儿结局的临床研究

目的探讨羊水偏少孕妇发生胎儿不良结局的危险.方法 2002年8月～2002年12月在四川省人民医院产科住院分娩的产妇202例,羊水指数(AFI)测量8.1～20cm为羊水量正常,5.1～8.0cm为羊水偏少.围产儿不良结局包括胎儿宫内窘迫、5分钟Apgar评分≤7、胎儿生长受限(FGR)、死胎、胎儿畸形发生率.结果围产儿不良结局的发生率羊水偏少组较正常组发生率增高,FGR发生率较正常组增加两倍.结论产前检查羊水偏少患者发生围产儿不良结局及FGR的风险增高.     

妊娠足月羊水过少及羊水偏少对围生结局影响

目的对比研究妊娠足月羊水过少和羊水偏少的分娩及围生儿结局。方法回顾性分析2008年5月-2011年5月我院妊娠足月48例羊水过少、57例羊水偏少孕妇,并随机抽取同期B超检查羊水量正常、无明显高危因素经阴道试产的足月孕妇50例作为对照组,比较三组的分娩方式和围生儿结局。结果羊水过少组急诊剖宫产率显著高于羊水偏少及对照组(P0.01),但羊水偏少组急诊剖宫产率与对照组比较无显著差异(P0.05);羊水过少组中胎儿窘迫、羊水污染、新生儿窒息率均高于对照组(P0.05)及羊水偏少组,但羊水偏少组与对照组比较无显著差异(P0.05)。结论羊水过少对围产儿的影响大,须加强监护,选择适时合理的分娩方式终止妊娠;羊水偏少孕妇应动态监测羊水变化,可在严密监护下行阴道试产。     

The biochemical composition of amniotic fluid and of maternal and fetal blood at various periods of pregnancy

Summary The content of sugar, chlorides, urea, nitrogen and of total proteins was studied simultaneously in amniotic fluid maternal and fetal blood. Investigations covered 136 women at various terms of pregnancy (8–40 weeks). With the progress of pregnancy the biochemical composition of amniotic fluid changed as follows: there was a rise of urea, rest nitrogen and of the total protein; sugar concentration dropped; chloride level remained unchanged.There was no parallelism between the biochemical changes in the amniotic fluid on one hand, and the changes in the maternal and fetal blood on the other. The aforementioned biochemical investigations serve as a conclusive confirmation of the secretory theory of the amniotic fluid origin and contradict that of transudation.(Presented by Active Member of the Akad. Med. Nauk SSSR V. V. Parin) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 51, No. 3, pp. 64–66, March, 1961     

HLA–D and –DR antigens on human amniotic fluid cells

Human amniotic fluid cells, known to express HLA-A, -B, and -C antigens, were tested for the presence of lymphocyte-stimulating antigens (LD or HLA-D) using modifications of the mixed lymphocyte culture (MLC) and primed lymphocyte typing (PLT) tests. Peripheral blood lymphocytes were co-cultured with various concentrations of allogeneic amniotic fluid cells, either growing as a monolayer culture in microtiter plates or suspended in medium following treatment with trypsin. The kinetics of such mixed lymphocyte amniotic fluid cell culture (MLAC) reactions were followed during days 3 to 8. Under none of these conditions did amniotic fluid cells significantly stimulate allogeneic lymphocytes, even after lymphocytes were specifically primed in the PLT assay to the HLA-D antigens segregating in the family of the amniotic fluid cell donor. Furthermore, in three-cell experiments, amniotic fluid cells failed to inhibit an ongoing MLC reaction, indicating that the absence of proliferative response to amniotic fluid cells is not due to active suppression. Taken together, these data strongly suggest that amniotic fluid cells either do not express HLA-D antigens or do not express them in a form that is detectable in either primary or secondary MLC.     

The Value of Amniotic Fluid Interleukin-6, White Blood Cell Count,and Gram Stain in the Diagnosis of Microbial Invasion of the Amniotic Cavity in Patients at Term

PROBLEM: Subclinical microbial invasion of the amniotic cavity occurs in 18.8% of women with term labor and intact membranes and in 34% of patients with term PROM and is a risk factor for the development of puerperal infection related morbidity. Although amniotic fluid white blood cell count, interleukin-6 determination, and Gram stain examination have been used for the diagnosis of intrauterine infection in patients with preterm labor and preterm premature rupture of membranes, no information is available about the accuracy and specific cut-off values for these tests in patients at term. The purpose of this study was to compare the performance of the amniotic fluid Gram stain examination, white blood cell count, and interleukin-6 determination in the identification of microbial invasion of the amniotic cavity in patients at term with and without PROM. METHOD: Amniotic fluid was retrieved from 148 patients with term gestations (90 patients with spontaneous labor and intact membranes and 58 patients with PROM). Samples were cultured for bacteria and Mycoplasma species. Amniotic fluid Gram stain, white blood cell count, and interleukin-6 determinations (ELISA, sensitivity: 43 pg/ml) were performed in all samples. Microbial invasion of the amniotic cavity was defined as a positive amniotic fluid culture for microorganisms. Analysis was conducted using Mann-Whitney U test, Fisher's exact test, receiver operating characteristic curves and logistic regression. RESULTS: Patients with spontaneous labor and intact membranes: The prevalence of microbial invasion of amniotic cavity in this group was 15.6% (14/90). The most sensitive test for the detection of microbial invasion of the amniotic cavity was amniotic fluid interleukin-6 determination (sensitivity for: interleukin-6 ≥ 5.7 ng/ml = 86%, white blood cell count ≥ 20 cells/mm³ = 64%, Gram stain = 28%). The most specific test was the Gram stain of the amniotic fluid (specificity for: Gram stain = 84%, interleukin-6 = 79% and white blood cell count = 63%). Multiple logistic regression demonstrated that amniotic fluid interleukin-6 concentration was the only covariate that retained statistical significance when intrauterine infection was used as outcome variable. Patients with PROM: The prevalence of a positive amniotic fluid culture in this group was 39.7% (23/58). Logistic regression demonstrated that only interleukin-6 retained a significant relationship with the results of amniotic culture when all variables were entered simultaneously into a model to predict amniotic fluid culture results. The most sensitive tests for the detection of intrauterine infection were interleukin-6 determination and white blood cell count (sensitivity for interleukin-6 ≥ 3.4 ng/ml and white blood cell count ≥ 20 cells/mm³ = 69.6% for both). The most specific test was Gram stain (97.1%). CONCLUSIONS: Amniotic fluid interleukin-6 determination is the best rapid test for the detection of microbial invasion of the amniotic cavity in patients at term with and without PROM. When this test is not available, amniotic fluid Gram stain and white blood cell count represent valid diagnostic tools to assess the microbial state of amniotic cavity.     

母体循环血找羊水有形成分的方法探讨

目的提高显微镜检查母体循环血中羊水有形成分的检出率,以便辅助临床早期快速确诊羊水栓塞。方法将足月产妇羊水与健康产妇静脉血按不同比例混合,在不同速度离心后取血浆层镜检,找出其羊水有形成分的最低检出限,然后吸取血浆层再以不同速度离心,观察其羊水有形成分最低检出限的变化。同理将24份羊水栓塞产妇的静脉血经两次不同速度离心后镜检羊水有形成分,比较其检出率差异。结果第一次以1000rpm离心5min后镜检出羊水有形成分的羊水／血液比例最低,为1：64;然后取1000rpm离心5min后的血浆层再经4000rpm离心3min,羊水有形成分最低检测限降低至羊水／血液为1：256。羊水栓塞患者血液标本经1000rpm离心5min后镜检检出率最高为33．3％,然后取1000rpm离心5min后的血浆层再行4000rpm离心3min,可将羊水有形成分检出率提高至66．6％,其差异具有统计学意义（χ^2=6．125,P〈0．05）。结论羊水栓塞母体循环血找羊水有形成分时应进行二次离心,第一次1000rpm 5min,取血浆再4000rpm 3min,然后取沉淀物镜检找羊水有形成分。     

Concentration of fetal plasma and amniotic fluid interleukin-1 in pregnancies complicated by preterm prelabour amniorrhexis.

AIMS--To determine interleukin-1 beta (IL-1 beta) concentration in fetal and maternal plasma and amniotic fluid from pregnancies complicated by preterm prelabour amniorrhexis and to define the relation of this cytokine to intrauterine infection and the onset of labour. METHODS--Cross-sectional study of 23 pregnancies complicated by preterm prelabour amniorrhexis. Enzyme linked immunoassay was used to measure IL-1 beta concentration in fetal and maternal plasma and amniotic fluid. In each case, fetal blood and amniotic fluid were cultured for micro-organisms. RESULTS--In pregnancies with positive fetal blood and/or amniotic fluid cultures, plasma and amniotic fluid concentrations of IL-1 beta were higher and the interval between amniorrhexis and onset of labour was shorter than in the non-infected group. There were no significant associations between fetal plasma IL-1 beta and maternal plasma or amniotic fluid IL-1 beta concentrations, fetal leucocyte count or the interval between amniorrhexis and the onset of labour. CONCLUSIONS--These findings suggest that although intrauterine infection is associated with increased IL-1 beta concentrations in fetal plasma and amniotic fluid, there is no significant association between the concentration of IL-1 beta and the interval between amniorrhexis and the onset of labour.     

Capnocytophaga species: a cause of amniotic fluid infection and preterm labour

Subclinical amniotic fluid infection and subsequent preterm labour may occur with intact membranes. We report two cases of subclinical amniotic fluid infection with intact membranes presenting in preterm labour. Capnocytophaga species, fastidious Gram-negative bacilli normally found in oral flora, were isolated in pure culture from amniotic fluid obtained by transabdominal amniocentesis. The distinctive microbiological features and spectrum of infections associated with Capnocytophaga species, and the importance of recognition of subclinical amniotic fluid infection as a cause of preterm labour, are discussed.     

An Interleukin-23 Binding Protein in Mid-Trimester Amniotic Fluid

Problem  The binding of mid-trimester amniotic fluid to cytokines was evaluated.
Method of study  Purified tumor necrosis factor-α (TNF-α), interleukin (IL)-10, IL-12, and IL-23 were incubated with amniotic fluid from 25 women undergoing a mid-trimester amniocentesis, or with bovine serum albumin or saline, and cytokine binding to monoclonal antibodies was quantitated by ELISA. Aliquots of amniotic fluid were heated to 95°C for 15 min and then retested for IL-23 binding. The effect of amniotic fluid dilution on IL-23 quantitation was evaluated.
Results  All amniotic fluids had a negligible effect on TNF-α, IL-10, and IL-12 detection. In marked contrast, pre-incubation with amniotic fluid from each subject reduced the subsequent ability to detect IL-23 by >50%. The extent of inhibition was directly proportional to the amniotic fluid dilution and was markedly reduced following heating at 95°C for 15 min. Amniotic fluids from White, Black, Asian, East Indian, and Hispanic women were equally effective.
Conclusion  Interleukin-23 and IL-12 share a common p40 subunit and no inhibition of IL-12 was apparent. It appeared that a component of mid-trimester amniotic fluid specifically interacts with the p19 subunit unique to IL-23. Mid-trimester amniotic fluid reactivity with IL-23 may be a mechanism to limit intra-amniotic neutrophil-derived inflammation.