Effect Of Amniotic Fluid Research Articles

Effects of amniotic fluid on human keratinocyte gene expression: Implications for wound healing.

Cutaneous wounds can lead to huge suffering for patients. Early fetal wounds have the capacity to regenerate without scar formation. Amniotic fluid (AF), containing hyaluronic acid (HA), may contribute to this regenerative environment. We aimed to analyse changes in gene expression when human keratinocytes are exposed to AF or HA. Human keratinocytes were cultured to subconfluence, starved for 12 h and then randomised to be maintained in (1) Dulbecco's modified Eagle's medium (DMEM), (2) DMEM with 50% AF, or (3) DMEM with 50% fetal calf serum (FCS). Transcriptional changes were analysed using microarray and enriched with WebGestalt and Enrichr. Additionally, eight diagnostic genes were analysed using semiquantitative real‐time PCR to investigate epidermal differentiation and cellular stress after HA exposure as an alternative for AF exposure. The AF and FCS treatments resulted in enrichment of genes relating to varied aspects of epidermal and keratinocyte biology. In particular, p63‐, AP1‐ and NFE2L2‐ (Nrf2) associated genes were found significantly regulated in both treatments. More genes regulated by FCS treatment were associated with inflammatory signalling, whilst AF treatment was dominantly associated with molecular establishment of epidermis and lipid metabolic activity. HA exposure mostly resulted in gene regulation that was congruent with the AF microarray group, with increased expression of ITGA6 and LOR. We conclude that AF exposure enhances keratinocyte differentiation in vitro, which suggests that AF constituents can be beneficial for wound‐healing applications.

Inhibitory effects of amniotic fluid on the activated protein C anticoagulation system in maternal plasma.

Pulmonary thromboembolism (PTE) is one of the leading causes of maternal mortality. We previously reported that possible contamination of amniotic fluid (AF) into maternal circulation accelerated thrombin production and activated platelet function in maternal blood through the extrinsic pathway, which may be associated with the high incidence of PTE in early puerperium. However, it remains unclear whether the maternal anticoagulation system, e.g., the activated protein C (APC) pathway, contributes to the hypercoagulable condition induced by AF. Our previous study using an endogenous thrombin potential (ETP)-based assay revealed that sensitivity to APC was reduced during the postpartum first day, i.e., immediately after delivery, when parturients were supposed to be exposed to AF. Our aim is to investigate the susceptibility of maternal plasma to APC when mixed with AF. We collected plasma from 51 pregnant females and mixed with AF as well as APC. APC-sensitivity ratio (APC-sr) was calculated using the ETP-based assay. Addition of AF to maternal plasma showed a significant increase of ETP in the presence of APC. APC-sr was significantly increased, indicating decreased sensitivity to APC, after AF mixture to maternal plasma. The present APC-sr difference with AF contamination was smaller than that we reported previously in venous thromboembolism cases. The inhibitory effects of AF on the APC anticoagulation pathway may contribute, at least partly, to further promotion of thrombin production induced by AF. Combined with other classical thrombophilic risk factors, the present findings support possible involvements of AF exposure in the high incidence of PTE in early puerperium.

The effects of amniotic fluid and foetal cord blood cotinine concentrations on pregnancy complications and the anthropometric measurements of newborns

Our objective was determining the effects of amniotic fluid (AF) and fetal cord blood (FCB) cotinine concentrations on pregnancy complications and the anthropometric measurements in the newborns whose mothers underwent amniocentesis. This study was conducted as a case-control study, in Turkey. A total of 250 pregnant women with amniocentesis indication were recruited into the study and the cotinine levels in the AF and FCB were determined. A smoking habit did not statistically affect the incidence of pregnancy complications (p>.05). The birth weights of the newborns were negatively correlated with the AF cotinine levels. The incidences of low birth weight, low Apgar scores and RDS were positively correlated with higher levels of cotinine in AF and FCB. It is important for healthcare staff to provide training and consultancy services for the health improvement of pregnant women and the prevention of smoking during pregnancy.Impact statementWhat is already known on this subject? The pre-pregnancy smoking habit usually continues during the pregnancy. A significant negative correlation was present between the foetal cord blood cotinine levels and the birth weight.What do the results of this study add? The anthropometric measurements of the newborns born from mothers with high AF cotinine levels were lower than newborns born from mothers with low amniotic fluid cotinine levels. Respiratory Distress syndrome is more often determined in newborns born from mothers with high AF cotinine levels.What are the implications of these findings for clinical practice and/or further research? Future studies should be performed to investigate the effects of cigarette smoking on the health problems, the growth characteristics and the neurological development of newborns and infants within the first year of life.

Amniotic fluid embolism: moving diagnosis through the time. From the mechanical pulmonary vascular occlusion until an immuno - inflammatory pathogenesis?

Amniotic fluid embolism (AFE) is a rare, catastrophic syndrome that presents during labor and delivery or immediately postpartum. Efforts to develop a clinical diagnostic test are ongoing; however the diagnosis still relies on rapid bedside evaluation and depends on the exclusion of other diseases. Classically, the diagnosis was made at autopsy, with the demonstration of squamous cells or debris in the maternal pulmonary vasculature. Clinico-pathological correlations have strengthened the evidence for a role of the immune system in the pathogenesis of AFE and have lead to the development of new laboratory tests, such as the serum tryptase and complement measurements, which should provide scientific support for the presumed immunological mechanism of AFE. Recently, studies on the effects of amniotic fluid (AF) on platelet - neutrophil aggregation and neutrophil/platelet activation have opened new insight in the comprehension of the mechanisms underlying AFE, suggesting that a severe inflammatory response might have a paramount causative role, so opening new diagnostic and therapeutic perspectives. Considering the complex interplay between the different mechanisms involved in the pathogenesis of AFE, the diagnosis still arises from a complex diagnostic puzzle in which clinical, macroscopic, laboratory, histological and immunohistochemical data converge toward AFE.

Effect of amniotic fluid on the in vitro culture of human corneal endothelial cells

The present study was designed to evaluate the effects of human amniotic fluid (HAF) on the growth of human corneal endothelial cells (HCECs) and to establish an in vitro method for expanding HCECs. HCECs were cultured in DMEM-F12 supplemented with 20% fetal bovine serum (FBS). Confluent monolayer cultures were trypsinized and passaged using either FBS- or HAF-containing media. Cell proliferation and cell death ELISA assays were performed to determine the effect of HAF on cell growth and viability. The identity of the cells cultured in 20% HAF was determined using immunocytochemistry (ICC) and real-time reverse transcription polymerase chain reaction (RT-PCR) techniques to evaluate the expression of factors that are characteristic of HCECs, including Ki-67, Vimentin, Na+/K+-ATPase and ZO-1. HCEC primary cultures were successfully established using 20% HAF-containing medium, and these cultures demonstrated rapid cell proliferation according to the cell proliferation and death ELISA assay results. The ICC and real time RT-PCR results indicated that there was a higher expression of Na+/K+-ATPase and ZO-1 in the 20% HAF cell cultures compared with the control (20% FBS) (P < 0.05). The 20% HAF-containing medium exhibited a greater stimulatory effect on HCEC growth and could represent a potential enriched supplement for HCEC regeneration studies.

Odor-induced crawling locomotion in the newborn rat: Effects of amniotic fluid and milk.

Early locomotion in the neonatal rat previously has been reported 3 days after birth during exposure to an odor of biological relevance (nest material). The current study explores if other ecologically relevant stimuli-amniotic fluid (AF) and milk-could evoke a similar locomotor response in the newborn rat and whether the endogenous opioid system mediates the response. Newborn rats tested 24 hr after birth were presented with the odors of AF or milk while placed in a runway. Pups expressed crawling and moved along the runway in response to direct exposure to the odors of AF and milk (Exp. 1). However, there was no evidence that this crawling response was altered after pretreatment with the opioid antagonist naloxone (Exp. 2). This study provides evidence of the capacity of AF and milk to evoke coordinated motor behavior, suggesting that they may play a role in the development of fundamental motor patterns.

Effect of amniotic fluid on blood coagulation

Amniotic fluid embolism (AFE) is a catastrophic complication of pregnancy. The incidence of AFE is very rare, and the clinical presentation; central hemodynamic data in humans are typically obtained more than 1 hour after the event and from only the subset of women who have survived the initial insult. This makes the exact pathophysiology remain elusive, despite numerous attempts at understanding AFE syndrome. We tried to evaluate the effect of amniotic fluid on blood coagulation by making a simple in-vitro model, using an activated clotting time (ACT) monitor.

Previable rupture of membranes: Effect of amniotic fluid on pregnancy outcome

Objective To evaluate pregnancy outcome and the role of the amount of amniotic fluid (AF) in the prognosis of extremely preterm (<24 weeks) premature rupture of membranes (EPPROM). Study design Women with EPPROM and on-going pregnancy after 1 week of expectant management were included. Exclusion criteria: fetal anomalies, termination of pregnancy and spontaneous recovery of AF within the first week. The effect of the large vertical pocket (LVP) on pregnancy outcome was assessed by a Cox regression model which included three covariates: LVP measurements from rupture to 24 weeks, gestational age at rupture of membranes and sealing procedure. Results Thirty-seven women were included in the study. The overall survival rate after the neonatal period was 40.5% (15/37) which increased to 62.5% (15/24) in neonates born alive after 24 weeks of gestation. Mean and S.D. of gestational age at rupture of membranes were 19.0 (±3.8) weeks. From rupture to 24 weeks, the pooled mean and standard deviation of LVP were 20.5 (±15.4) mm. Multivariate analysis showed that the likelihood for neonate survival increased by 2.7 (95% CI 1.45–4.65) for each 5 mm of LVP during the follow-up from rupture to 24 weeks. After controlling for AF amount, neither the gestational age at rupture nor the sealing procedure showed any significant effect on pregnancy outcome. Conclusion Although the prognosis of EPPROM is poor overall, survival improves as the amount of AF before 24 weeks increases.

P11.05: Previable rupture or membranes: effect of amniotic fluid on pregnancy outcome

To evaluate pregnancy outcome and the role of the amount of amniotic fluid (AF) in the prognosis of extremely preterm (< 24 weeks) premature rupture of membranes (EPPROM). Women with EPPROM and ongoing pregnancy after one week of expectant management were included. Exclusion criteria: fetal anomalies, termination of pregnancy and spontaneous recovery of AF within the first week. Patients were offered expectant management or a sealing procedure depending on AF quantification assessed twice weekly by the largest vertical pocket (LVP). The effect of the LVP on pregnancy outcome was assessed by a Cox regression model with 2 covariates: an updated time dependent (LVP measurements from rupture to 24 weeks) and a time constant (gestational age at rupture of membranes and sealing procedure). Thirty-seven women were included in the study. The overall survival rate after the neonatal period was 40.5% (15/37) which increased to 62.5% (15/24) in neonates born alive after 24 weeks of gestation. Mean and standard deviation of gestational age at rupture of membranes were 19.0 ( ± 3.8) weeks. Mean and standard deviation of LVP at admission and + 7d of rupture were 15.4 ( ± 11.3) mm and 19.8 ( ± 11.9) mm, respectively. From rupture to 24 weeks, the pooled mean and standard deviation of LVP were 20.5 ( ± 15.4) mm. Multivariate analysis showed that the likelihood for neonate survival increased by 2.5 (95% confidence interval 1.38–4.57) for each 5 mm of LVP during the follow-up from rupture to 24 weeks. After controlling for AF amount, neither gestational age at rupture nor the sealing procedure showed any significant effect on pregnancy outcome. Although the prognosis of EPPROM is poor overall, survival improves as the amount of AF before 24 weeks increases.

Effect of Amniotic Fluid on Coagulation and Platelet Function in Pregnancy: An Evaluation using Thromboelastography

Effect of Amniotic Fluid on Coagulation and Platelet Function in Pregnancy: An Evaluation using Thromboelastography

Effect of Amniotic Fluid on Peri-implant Capsular Formation

Although commonly used biomaterials are physically and chemically stable, nonimmunogenic, and nontoxic, implanted and blood-contact biomaterials trigger a wide variety of unwanted responses, including inflammation, thrombosis, infection, and fibrosis. Peri-implant fibrosis is the response most commonly seen by plastic surgeons. In this study, the authors hypothesized that as hyaluronic acid (HA) reduces scar formation by inhibiting the activity of mononuclear phagocytes and lymphocytes, human amniotic fluid (HAF), which contains high concentrations of HA, HA-stimulating activator (HASA), and other factors, might prevent the formation of fibrous capsules and capsule contracture when applied intraluminally. Two 1 x 1-cm silicone blocks were placed dorsally into separate surgically created pockets underneath the panniculus carnosus muscle, distant from the incisions, in each of the 10 rats in the study. At the time of implant insertion, 2 ml of HAF was instilled into the cranially located pockets in group 1, whereas 2 ml of saline solution was instilled into the caudally located pockets in group 2. After 6 months, intracapsular static and dynamic pressure measurements were made, and then all the peri-implant capsules were excised and fixed in 10% neutral buffered formaldehyde. The thicknesses of the capsules were measured in three different areas of each section, and a mean was calculated. Capsular firmness, according to the static and dynamic pressure readings, was significantly greater in the control group, which had saline solution introduced into the pocket, than in the treatment group, which had HAF used in the same manner. The mean total thickness of the capsules surrounding the implants was 876.7 microm in the control group, as comparied with 466.8 microm in the HAF-treated group. This difference was statistically significant (p < 0.001). Because of its ability to reduce capsular thickness and firmness and also because it can be stored in a freezer if it is prepared in a cell-free manner, HAF would appear to be a useful adjunct in the prevention of capsular contracture formation.

Effect of amniotic fluid cellular content on attic aeration pathways: Histologic observations of infants aged 2 to 4 months

Effect of amniotic fluid cellular content on attic aeration pathways: Histologic observations of infants aged 2 to 4 months

The vulnerable stomach in babies born with pure oesophageal atresia.

Nine babies with pure oesophageal atresia were treated in our institution in the years 1979-1996. All received a feeding gastrostomy as their initial operation. After initiation of gastrostomy feeds seven (78%) developed gastric complications, including two posterior gastric perforations (one fatal). We propose that the high complication rate is due to a small, abnormal stomach that is vulnerable to damage by operative trauma and the effects of handling large volumes of feed. We hypothesise that the stomach is abnormal because it has not been exposed to the maturing effects of amniotic fluid in utero. Feeds should be introduced very cautiously to these babies and built up very slowly.

Hepatocyte growth factor in human amniotic fluid promotes the migration of fetal small intestinal epithelial cells

OBJECTIVE: Previously we reported on the abundant existence of hepatocyte growth factor in amniotic fluid. This study was conducted to clarify the effects of hepatocyte growth factor in amniotic fluid on fetal intestinal epithelial cells. STUDY DESIGN: Amniotic fluid samples were obtained from 22 cases at various gestational ages. The effects of amniotic fluid and recombinant human hepatocyte growth factor on proliferation, migration, and morphogenesis of intestine 407 cells (a cell line derived from fetal intestinal epithelial cells) were investigated. RESULTS: The mobility of intestine 407 cells was stimulated by amniotic fluid in proportion to the concentration of hepatocyte growth factor in amniotic fluid with the same effect observed with recombinant human hepatocyte growth factor. This activity was neutralized by addition of antihuman hepatocyte growth factor antibody. Neither increased deoxyribonucleic acid synthesis nor morphogenesis in response to amniotic fluid was identified under the conditions used. CONCLUSIONS: Amniotic fluid stimulates intestinal epithelial cell migration by way of hepatocyte growth factor in amniotic fluid during development of the fetal intestine. (Am J Obstet Gynecol 1998;178:175-9.)

Effect of Amniotic Fluid in Corneal Sensitivity and Nerve Regeneration After Excimer Laser Ablation

To examine the effect of topical application amniotic fluids on the recovery of corneal sensitivity and nerve regeneration after excimer laser photokeratectomy, excimer laser was applied to 18 rabbits (VISX 20/20, 5 Hz, 7 microns depth: nine rabbits; 100 microns depth: nine rabbits). Human amniotic fluid (AF) was topically applied to the right eyes (AF group), and a balanced salt solution (BSS) was applied to the left eyes (BSS group). Corneal sensitivity was measured by using a Cochet-Bonnet aesthesiometer after weeks 1, 2, 4, 5, 8, and 12. Nerve-regeneration status was evaluated after weeks 2, 4, 5, 8, and 12 by gold chloride staining. Corneal sensitivity was initially subnormal and recovered close to the normal level at week 8. The sensitivity was higher in the AF group than in the BSS control group, except at week 2. Subepithelial nerve regeneration at the laser site was detected both at week 4 in the AF group and at week 5 in the BSS group. There was no significant correlation between the nerve-regeneration state and sensitivity changes. Long striated nerve regeneration from the deep stromal nerve was remarkable at the third month, especially in the BSS group. The BSS group showed more marked scarring of the superficial stroma, compared with the AF group. The nerve regeneration at the scar site was discontinued and delayed. Subepithelial leash nerves in the AF group were more abundant than those in the BSS group. The recovery of sensitivity and nerve regeneration were faster in the AF cornea than in the BSS cornea. These results suggest that the factors in AF helped the recovery of corneal sensitivity, nerve regeneration, and reduced scar formation.

Effect of amniotic fluid from patients with fetal pathology (anencephaly) on cell differentiation in nervous tissue culture

The addition of amniotic fluid from pregnant women with anencephaly to neuronal and organotypic cultures initiated from germinal brain cortex of 8–12-week-old human embryos has no appreciable effect on growth and differentiation of neurons. However, it stimulates the formation of endothelial channels and affects cell-to-cell interactions. This is assumed to be a factor associated with an abnormal development of the CNS in anencephaly.

Effects of Amniotic Fluid on Proteases

Fetuses are surrounded by amniotic fluid rich in nutrients and other factors essential to fetal development and possibly to its scarless wound healing. The purpose of this study was to determine whether amniotic fluid contains factors that regulate activities of major proteases involved in the process of wound healing (e.g., collagenase, hyaluronidase, elastase, and cathepsin B). Human amniotic fluid was assayed in vitro for inhibition or stimulation of the activity of these enzymes. Our results showed that amniotic fluid enhanced collagenase activity at a concentration of 66 micrograms protein (p < 0.01), but inhibited activities of hyaluronidase (132 micrograms protein; p < 0.05), elastase (170 micrograms protein; p < 0.05), and cathepsin B (19 micrograms protein; p < 0.01). This finding suggests that amniotic fluid could have an important role in flawless fetal wound healing by regulating these matrix-degrading enzymes.

Growth stimulatory effects of amniotic fluid and amniotic cell conditioned medium on human cells involved in wound healing

Amniotic membrane has been used successfully as a biological dressing for various kinds of wounds. In order to study exocrine activity in amniotic cells, we assessed the incorporation of 3H-thymidine in human fibroblasts and the increase in the number of human keratinocytes when stimulated with amniotic fluid and conditioned medium from amniotic cells. Both amniotic fluid and conditioned medium were shown to stimulate these cell types, which are crucial to the wound healing process. Amniotic fluid was the most potent of the two media tested. The effect exerted by amniotic fluid and conditioned medium were comparable to that of 10% fetal calf serum and a dose-dependent reponse was seen when the media were diluted. These results indicate that the special healing features seen in fetal wounds bathed in amniotic fluid, together with the wound healing properties of amniotic membrane used as a biological wound dressing, may be due to the exocrine activity of the amniotic cells.

86 The Effect of Amniotic Fluid on Platelet Function

86 The Effect of Amniotic Fluid on Platelet Function

Histologic changes in capsule formation around silicone implants after a single dose injection of amniotic fluid

Excisional fetal wounds exposed to amniotic fluid do not contract as opposed to those not exposed. In adult rabbits, the effect of amniotic fluid on capsule formation around silicone rubber cubes was investigated. The results showed that a single dose injection of amniotic fluid can modify the fibrous capsule formation histologically in the adult animal.