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At least 19 recordsLinked to original sources
PubMed1977

Amnion nodosum and congenital ichthyosis.

Histologic characteristics of the placentas in four cases of amnion nodosum and congenital ichthyosis, a rare association, are presented. Two cases were missed abortions of a single multiparous woman, supporting the hypothesis that in congenital ichthyosis amnion and skin share an abnormal genetic trait. As the amnion showed no hyperkeratosis, it is likely that the amniotic lesions are related to an increased deposition of keratotic plugs on the amnion. Oligohydramnios was verified in two cases; urinary tract malformations were absent in all. The histologic characteristics of the placentas were similar. Noteworthy was the aspect of the chorionic vessels, whose lumens were reduced or obliterated. Perhaps this feature contributed to the poor nutrition of the amnion, a fact assumed by some authors to explain lesions of amnion nodosum. As these vascular alterations are common after fetal death, it is only in the placenta of the newborn that the vascular changes, compatible with rubella vasculitis, may have altered the nutrition of the amnion.

Amnion↗
PubMed1977

Prolactin and fetal osmoregulation: water transport across isolated human amnion.

The addition of human or ovine prolactin to the fetal side of the human amnion is associated with a latent decrease in membrane permeability. The specificity of this effect of prolactin is observed when equimolar concentrations of human placental lactogen and human growth hormone were used in place of ovine prolactin and failed to influence water transport. Likewise, the extracellular transport of p-aminohippurate across human amnion was unaffected by the addition of ovine prolactin. Tritiated water transport under these circumstances, however, remained impaired. The addition of antibody to ovine prolactin completely blocked the effect of this polypeptide on membrane permeability. Permeability to tritiated water remained unchanged when synthetic arginine vasopressin was added to the fetal side of the amnion. The results imply an active role for prolactin on water transport across human amnion. Moreover, the latent period between the addition of the polypeptide and its subsequent influence on permeability suggests a biologic effect of this hormone. That this effect is related to ion transfer remains to be shown.

Amnion↗
PubMed1975

Human amnion and lung tissue culture systems for possible detection and study of human RNA tumor viruses.

A human lung and an amnion cell line were identified as highly susceptible to transformation by the rhabdomyosarcoma-114 (RD-114) virus pseudotype of murine sarcoma virus (MSV). MSV transformation on these two cell lines demonstrated a) "one-hit" kinetics with an MSV stock which contained a 100-fold excess of MSV over its detectable associate RD-114 helper virus and b) only a slight increase (2X) in focus-forming titers by the addition of optimal concentrations of RD-114 helper virus. These findings indicated that the primary MSV interaction with those amnion and lung cells was that of non-productive transformation; and this was confirmed by the isolation of sarcoma-positive leukemia (helper) virus-negative (S+Lminus) cells from cloned terminal foci of MSV transformed human amnion and lung cells. These MSV-susceptible human cell lines are the first human cells identified as capable of demonstrating the defective nature of MSV. Human candidate oncornaviruses have not, however, been detected to date with the use of normal lung and amnion cells and their S+Lminus derivatives as indicator systems. These cell lines were useful for the isolation and identification of a new RD-114-like virus from a cat cell line.

Amnion↗
PubMed1977

Human amnion metabolism. II. Incorporation of fatty acids into tissue phospholipids in vitro.

The rate of incorporation of 3H-arachidonic acid and 14C-palmitic acid into 15 term amniotic membranes was studied during incubation of tissues in an artificial amniotic fluid medium. Phospholipids were extracted from the amnions, separated by thin-layer chromatography, and both the radioactivity and the phosphorus associated with each phospholipid species were determined. The distribution of amnion phospholipids was: lecithin, 47 per cent; phosphatidyl ethanolamine, 30 per cent; sphingomyelin, 7 per cent; phosphatidyl inositol, 5 per cent; lysolecithin, 4 per cent; and other phospholipids, 6 per cent. During incubation, the specific activities of the phospholipids became maximal after 2 hours and remained constant for at least the next 2 hours. Arachidonic acid was incorporated mainly into lecithin (53 per cent) and phosphatidyl ethanolamine (27 per cent) whereas palmitic acid was incorporated mainly into lecithin (70 per cent). Incorporation of fatty acids was 33 per cent higher in amnions obtained after vaginal delivery than in those obtained before labor. From the known fatty acid composition of amnion phospholipids, it is concluded that there is a high rate of turnover of arachidonic acid relative to palmitic acid in lecithin.

Amnion↗
PubMed1976

Fetal respiration: quantitative measurements of amnionic fluid inspired near term by human and rhesus fetuses.

Observations reported now on primate pregnancies, human and rhesus, combined with earlier studies from this laboratory, demonstrate that normally appreciable volumes of amnionic fluid are inhaled and presumably exhaled throughout much of pregnancy. Through use of isotope-labeled red cells and porcelain microspheres placed at varying times in the amnionic sac, as well as fetal squames already present, it has been shown conclusively that inhalation of amnionic fluid is not necessarily a pathologic event. The volumes of amnionic fluid inhaled per 24 hours by human and rhesus fetuses late in pregnancy were remarkably similar, amounting on the average to at least 200 ml per kilogram. These observations confirm the much earlier qualitative studies of some others that previously had generally been discounted by many fetal physiologists.

Amniotic Fluid↗
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↗
PubMed1979

Infection of untreated primary human amnion monolayers with Chlamydia trachomatis.

For development of a laboratory model for chlamydial infection of the human genital tract, untreated primary human epithelial cell monolayers, prepared from each of four placentas, were infected with a stock strain of Chlamydia trachomatis isolated from the nasopharynx of an infant with pneumonia. Infectivity titrations were performed with use of standard procedures of chlamydial inoculation, and inclusions grown in amnion cell monolayers and in McCoy cells were measured versus infectious units inoculated. By linear regression analysis, untreated human amnion cells (y = 0.948x + 4.63, r = 0.9255) were as susceptible as McCoy cells treated with diethylaminoethyl dextran and 5-iodo-2-deoxyuridine (y = 1.104x + 5.35, r = 0.9804). Human amnion may prove a valuable model for study of human chlamydial infection and may have important implications for investigation of clinical disease.

Amnion↗
PubMed1975

[Studies of in vitro cultivated cells from the smooth muscle organs. 3. Effectiveness of some drugs on pulsation frequency of isolated smooth muscle cells of the chicken amnion].

The effects of some drugs on the beating frequency of isolated cells of the chick amnion cultivated on cover slips were investigated. Cholinergic and adrenergic agonists and antagonists, serotonine, antispasmodics, coronary dilatants and local anesthetics influenced the beating frequency significantly. The isolated chick amnion cells equal in their pharmacological behaviour the intact chick amnion and smooth muscle cells of mammals but differ from isolated beating heart cells.

Adrenergic beta-Antagonists↗
PubMed1978

Simian virus 40 (SV40) production from SV40-transformed human amnion cells of established lines.

Sixteen established cell lines of simian virus 40 (SV40)-transformed human amnion cells were examined for SV40 production. Many of these lines produced SV40 for extensive periods. Virus production had not ceased for 2 lines after 18 months, for 3 lines after 12 months, and for 3 lines at 3 months after recovery from "crisis". Three lines became virus-free in the first month, 1 line in the second month, 1 in the third month, and 1 in the fourth month, and 2 lines stopped virus production between 6 and 11 months after recovery. The virus titers were relatively low. Inclusion body-containing cells were infrequent. In contrast, in most cultures of SV40-transformed human fibroblasts rescued from crisis, no infectious virus was demonstrated, although exceptions have been reported. Virus was produced after heterokaryon formation of cells of the virus-free amnion lines with CV-1 cells in the presence of inactivated Sendai virus, as observed for SV40-transformed human fibroblasts. During the crisis period, some of the SV40-transformed amnion cells produced substantial amounts of virus. Titers decreased during the later periods of crisis. The most pronounced decrease in titers was in cultures from which established lines were recovered.

Amnion↗
PubMed1979

The amnion regulates movement of fetally derived alpha-fetoprotein into maternal blood.

The present investigation documents that, under normal conditions, most fetally produced AFP reaches the maternal circulation via diffusion across the amnion from amniotic fluid. This has been determined by comparing maternal serum AFP levels with amniotic fluid albumin concentrations in paired samples. The proportionally demonstrated between them indicates a proportional, transamniotic exchange of the two proteins, each originating on opposite sides of the amnion. Albumin is known to reach amniotic fluid by transamniotic diffusion from maternal blood. All amnions restrict AFP movement into maternal serum, but some are distinctly more restrictive than others; in such cases, a relatively greater increase in amniotic fluid AFP concentration would likely have to occur from a fetal lesion before being reflected in maternal serum. Inconsistencies found in several paired samples identify that other variables may also influence passage of AFP to the mother.

Amnion↗
PubMed1978

Specific production of prostaglandin E by human amnion in vitro.

Prostaglandin production by intra-uterine human tissues has been investigated using a method of tissue superfusion. Tissues were obtained at elective Caesarean section and after spontaneous vaginal delivery. It was found that all the tissues studied (amnion, chorion, decidua and placenta) produced more prostaglandin E (PGE) and 13,14-dihydro-15-keto-prostaglandin F (PGFM - the major circulating metabolite of prostaglandin F) than prostaglandin F (PGF). Amnion produced significantly more PGE (but not PGF or PGFM) than any other tissue. Prostaglandin production by each tissue was similar whether it was taken at elective Caesarean section or after spontaneous vaginal delivery.

Amnion↗
PubMed1979

Studies on the ultrastructure of the term amnion in pathological pregnancy.

The ultrastructure of the amniotic epithelium at term was examined in cases of intrauterine growth retardation of the fetus and compared with amnions obtained from women with a clinically unremarkable pregnancy. In uterine growth retardation the amniotic cells exhibit a general deficiency of a series of functionally significant cell organelles. The RER is insufficiently developed, there is a diminution of the normally numerous free ribosomes as well as of those cell organelles which are involved in secretory function. A further atypical finding is the common lack of intercellular canals playing an important role in the transamniotic exchange of material. Besides this, a very poor development or a complete disintegration of the microfilamentous cytoskelet is generally noticed. The present findings give once again evidence for a very close relation between the structural appearance of the intercellular diffusion canals and the microfilamentous system. The results presented are suggestive of an amnion which is in a state of reduced secretory activity, additionally, due to the common lack of intercellular canals an inhibition of the interepithelial passage between the maternal and amniotic compartment cannot be excluded.

Amnion↗
PubMed1979

JC human papovavirus replication in human amnion cells.

JC human papovavirus was found to replicate in primary human amnion cells. The virus has undergone eight passages in amnion cells and was identified by serological methods as JC virus. By restriction endonuclease analysis of the viral DNA, the fragments observed were identical to those previously reported for the prototype strain.

Amnion↗
PubMed1978

Haemophilus influenzae amnionitis associated with prematurity and premature membrane rupture.

Prematurity and premature rupture of the membranes present major obstetric problems. When associated with amnionitis, the result may be disastrous. A case of Haemophilus influenzae aminionitis in association with premature rupture of the membranes is presented. The rarity of this organism as a causative agent in amnionitis and its possible causative role in premature membrane rupture are considered in review of the scant relevant literature.

Adult↗
PubMed1978

The cerebral malformation of the amnionic band syndrome.

The Amnionic Band Syndrome is a not uncommon disorder of the fetus which may result in cerebral malformations that mimic anencephaly. It is important to distinguish these two entities because of differences in pathogenesis and risk of recurrence. A preliminary stillborn female of 29 weeks gestation with multiple anomalies, including cerebral-placental fusion, cranial agenesis, cleft lip, syndactyly and ectopic liver is presented. These malformations are typical of the Amnionic Band Syndrome, an entity which has not been described in the neurologic literature.

Abnormalities, Multiple↗
PubMed1978

Oligohydramnios and fatal pulmonary hypoplasia without amnion nodosum.

Two cases of fatal pulmonary hypoplasia associated with hydrorrhea gravidarum are presented. Amnion nodosum was present in one case but not the other. The pathogenesis of amnion nodosum is reviewed, and the clinical implications of this pathologic finding are discussed in relation to whether the underlying pathology is renal agenesis or amniorrhea.

Amnion↗
PubMed1978

Infection of human amnion cells with cytomegalovirus.

Human cytomegalovirus (CMV), known to replicate in vitro in human fibroblastic cells, was found to replicate in epithelial human amnion (HA) cells. Large syncytia formed in these cells after infection with CMV; inclusion bodies were observed in the nuclei, and CMV antigens were demonstrated in both the cytoplasm and the nucleus by indirect immunofluorescence techniques. The synthesis of virus DNA was also detected, and the production of infectious virus was followed. The titers were lower (from 10(4) to 6 X 10(5) using different isolates of CMV) than those obtained in human embryo fibroblast (HEF) cells, and the replication cycle was slower in HA than in HEF cells.

Amnion↗