(n.) The inner layer of the skin or integument of an animal.
(n.) The innermost layer of the blastoderm and the structures derived from it; the hypoblast; the entoblast. See Illust. of Ectoderm.
Example Sentences:
(1) In contrast, F9ACC19, an endodermal cell line derived from F9 cells, synthesizes only minor amounts of lactosaminoglycans and a high proportion of smaller glycopeptides.
(2) Both genes are expressed in the fetal liver, gut, and visceral endoderm of the yolk sac and are repressed shortly after birth in the liver and gut.
(3) Examination of the two types of tissue fragments revealed that IS-treated ICMs almost invariably retained viable endoderm cells whereas MS-isolated ectoderms did so only exceptionally.
(4) LIF inhibits differentiation under several conditions which lead to endodermal and mesodermal cell lineages including skeletal and cardiac muscle.
(5) This epithelial cell was tentatively identified as primitive extraembryonic endoderm by its ultrastructural appearance and its possession of cytokeratin intermediate filaments.
(6) The majority of testicular germ cell tumors in adults are accompanied by neoplastic intratubular germ cells; these cells were uniformly absent in ten pure yolk sac tumors (endodermal sinus tumors) of the testicle in children studied morphologically and immunohistochemically.
(7) After the treatment in toto of the embryos from various species of Anura by cAMP, the number of primordial germ cells (PGC) in genital ridges is strongly reduced; the most part of the PGC are found in the endoderm.
(8) Our experience suggests that the optimal management of patients with primary mediastinal endodermal sinus tumor requires an aggressive multidisciplinary approach guided by the extent of the tumor and the serum tumor marker levels.
(9) The tissues of the endodermal and mesodermal origin were also present in small quantities.
(10) Although the liver first forms as a discrete epithelial bud of endodermal tissue at stage 12-14 (45-53 h after laying), canaliculi were first detected by our antibodies at low levels in 4-day embryos and at high levels in stage 27 (5 days after laying) and later embryos.
(11) The cell cycle time of the gland cells appears to be longer than that of the epithelial cells of the endoderm throughout the animal.
(12) As development proceeded during primitive streak stages, the visceral and parietal endoderm became positively stained.
(13) The F9 cell is a mouse embryonal teratocarcinoma which can be induced to differentiate into visceral endoderm by treatment with retinoic acid (RA).
(14) Multiple hamartoma syndrome, also known as Cowden's disease, is a rare genodermatosis with multiple organ system involvement affecting tissues derived from ectodermal, endodermal, and mesodermal tissue layers.
(15) This finding suggests the identification of a cell population that is analogous to parietal endoderm in some eutherian animals.
(16) We recently showed that yolk sac is involved in the control of metabolism and action of vitamin D in the fetoplacental unit, since its endodermal cells contain a 24-hydroxylase for vitamin D metabolites and the 1,25-dihydroxyvitamin D receptor.
(17) These data thus demonstrate the production and presence of RBP mRNA and TTR mRNA, and the synthesis and secretion of RBP and TTR, by F9 cell embryoid bodies (specifically by visceral endoderm-like cells).
(18) We conclude that yolk-sac-derived teratomas are of endodermal origin because of the fact that the paternal X chromosome is inactivated in the yolk sac endoderm, whereas in the yolk sac mesoderm, as in the embryo, the inactivation is at random.
(19) A particularly interesting proteinase active at alkaline pH values is detected in the trophoblast-endoderm complex.
(20) It is therefore considered that, although there is good evidence that serum AAT is produced by endodermal sinus tumour elements, serum AAT is not a useful monitor of disease activity in these patients, especially when compared with serum AFP, the value of which is well recognized.
Hypoblast
Definition:
(n.) The inner or lower layer of the blastoderm; -- called also endoderm, entoderm, and sometimes hypoderm. See Illust. of Blastoderm, Delamination, and Ectoderm.
Example Sentences:
(1) Gastrulation is accompanied by a sharp increase in the AChE activity which was most pronounced in anterior hypoblast.
(2) (1) Removal of both the area opaca and the marginal zone of the area pellucida from a blastoderm stripped of its hypoblast (type-IV operation) prevents the regeneration of a normally functioning primary hypoblast.
(3) These results show that the two main properties of the posterior marginal zone (contributing to the hypoblast and controlling the site of primitive streak formation) are separable, and reside in different germ layers.
(4) The 36 hour stage was represented by bulky growth of mesodermal-like cells and changes in hypoblast layer where some of the cells degenerated and some were transformed to mesenchymal spindle-like cells.
(5) Tritiated quail hypoblast (after incubation of the embryo in the presence of 3H-glucosamine) was transplanted onto unlabelled chicken blastoderm deprived of its hypoblast.
(6) In the area pellucida, the fibronectin was (1) associated with the basal lamina of the epiblast, (2) present between epiblastic and hypoblastic cells and (3) occasionally internalized in hypoblastic cells.
(7) It was found that the deep (endodermal) portion of the posterior marginal zone contributes to the hypoblast and to the junctional endoblast, while the epiblast portion of the same region contributes to the epiblast of the primitive streak and to the definitive (gut) endoderm derived from it.
(8) TGF-beta 1 precursor was seen in both the epiblast and the hypoblast.
(9) Removal of the deep part of the marginal zone prevents regeneration of the hypoblast but not the formation of a primitive streak.
(10) Chick embryos treated with tunicamycin (TN), a specific inhibitor of N-linked glycosylation of proteins, show little or no ECM, diminished cell adhesion and a dramatic alteration in the architecture of the epiblast and of the hypoblast.
(11) A chemical basis for the transmission of signals during gastrulation has been investigated by using chimaeric embryos resulting from the combination of 3H-glucosamine-labelled and unlabelled hypoblast with epiblast taken from chicken and quail embryos at stage 3 of Vakaet (1970).
(12) The roof of the vesicle is constructed to rather large columnar cells which are in continuity wiht hypoblast cells.
(13) By contrast, alpha-amanitin resulted in a decrease in synthesis of several polypeptides, which are either undetectable or weakly present in the hypoblast.
(14) It was found that the first cells that appeared between the primitive endoderm (hypoblast) and trophoblast were separated from the latter by a basal lamina but appeared to be either loosely attached to the endoderm or to have been detached from it.
(15) The hypoblast explant tended to fragment into smaller groups of cells, many of which migrated around the definitive endoblast, thus mimicking the situation in vivo.
(16) Transfer of label may occur to mesoblast cells, but not between chicken and quail hypoblast cells.
(17) The morphology of the chimaeric embryos, as studied by scanning electron microscopy, suggests a direct deposition of these macromolecules by filopodia of the dorsal surface of the hypoblast.
(18) The labeled hypoblast was recombined with its denuded unlabeled epiblast.
(19) In comparison with the definitive endoblast, the hypoblast cells attached more readily to the glass, produced larger ruffle membranes, moved more rapidly, showed poorer contact-inhibition of locomotion and showed a greater tendency to break away from the main explant.
(20) The hypoblast, mesoderm and epiblast of gastrulating chick embryos have some HNK-1-related proteins in common, while others are unique to specific tissues.