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Related to trophoblast: chorion, placenta, cytotrophoblast, blastocyst cavity


The outermost layer of cells of the mammalian blastocyst that attaches the fertilized ovum to the uterine wall and serves as a nutritive pathway for the embryo.

tro′pho·blas′tic adj.


(Biology) the outer layer of cells of the embryo of placental mammals, which is attached to the uterus wall and absorbs nourishment from the uterine fluids
[C19: from tropho- + -blast]
ˌtrophoˈblastic adj


(ˈtrɒf əˌblæst, ˈtroʊ fə-)

the layer of extraembryonic ectoderm that nourishes the embryo or develops into fetal membranes with nutritive functions.
troph`o•blas′tic, adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.trophoblast - the membrane that forms the wall of the blastocyst in early development; aids implantation in the uterine wall; "after implantation of the blastocyst in the uterine wall the trophoblast divides into two layers, the chorion and the placenta"
blastosphere, blastula - early stage of an embryo produced by cleavage of an ovum; a liquid-filled sphere whose wall is composed of a single layer of cells; during this stage (about eight days after fertilization) implantation in the wall of the uterus occurs
tissue layer, membrane - a pliable sheet of tissue that covers or lines or connects the organs or cells of animals or plants
References in periodicals archive ?
Mechanistic evidence exists for the role of BPA in inducing oxidative stress and effecting trophoblast turnover (Babu et al.
The distinct invasiveness of the trophoblast and the intimacy of the junctional zone are associated with a characteristic fibrinoid material, probably of trophoblastic origin (Kirby et al.
ATLANTA, July 28, 2015 /PRNewswire/ -- SeraCare Life Sciences, a leading partner to global in vitro diagnostics manufacturers, announced today at the American Association of Clinical Chemistry (AACC) meeting that it has signed a licensing agreement with the University of California, San Francisco (UCSF) for the use of Trisomy 21 (T21), Trisomy 18 (T18) and Trisomy 13 (T13) trophoblast cell line material as a component for creating "patient-like" reference materials for Non-Invasive Prenatal Testing (NIPT) of chromosomal abnormalities.
Pathophysiology of placenta creta: the role of decidua and extravillous trophoblast.
It has been proposed that a breach in the trophoblast layer lining the chorionic villi may result in contact of Hofbauer cells (specialised fetal macrophages) with maternal blood and amniotic fluid.
Although the mechanism underlying this association is not known, one possible explanation is that when a woman carries an embryo that is completely allogenic, it triggers modified immune tolerance that leads to impaired trophoblast implantation.
The reasons for a false-negative result include the observations that up to 10% of women may not even have implanted on the day of their expected menses, the amount of hCG secreted by the trophoblast during early pregnancy can vary by 10-fold, the monoclonal antibodies used in the test may not recognize the major forms of hCG present in the urine during early pregnancy, high concentrations of the f-core fragment of hCG can produce interference in some of the tests, and, rarely, the highdose hook effect can occur (13, 19-21).
They cover the female gamete; the male gamete; the embryo/blastomere; trophoblast, amniotic fluid, endometrium, and bone marrow; and new developments in stem-cell research.
The trophoblast marker genes, cytokeratin 8 and 18, showed lower expression levels in the SCNT blastocysts compared with in vivo blastocysts.
Senior author Harvey Kliman, research scientist in the Department of Obstetrics, Gynaecology and Reproductive Sciences at the Yale School of Medicine, and research collaborators at the MIND Institute at the University of California, Davis, have found that abnormal placental folds and abnormal cell growths called trophoblast inclusions are key markers to identify newborns at risk of autism.
Study leader Dr Erica Watson from the Centre for Trophoblast Research at the University of Cambridge, said that though their research focused on genetic mutations which disrupts the break down and metabolism of folic acid, they believe that folic acid deficiency in the diet would have a similar multi-generational impact on health.
11 Uterine NK cells appear to regulate placental and trophoblast growth and local immunomodulation, and control trophoblast invasion.