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At least 19 recordsLinked to original sources

PubMed1979

Endodermal germ cell carcinoma (endodermal sinus tumor) of the vagina in infant girls.

An endodermal sinus tumor (endodermal germ cell carcinoma) was diagnosed in a 1-year-old girl in the vagina after hemorrhage; the tumor was completely removed by radical abdominal surgery. Postoperative polychemotherapy was performed for two years with Actinomycin D, Adriamycin, Vincristin, and Cyclophosphamide. The infant is now tumor-free for 26 months, showing almost normal somatic and psychic development. The characteristic histological patterns and clinical course of this strongly malignant tumor are demonstrated, based on 25 published case reports of endodermal sinus tumors in the vagina of little girls (aged 5-26 months). This neoplasm in early infancy has to be separated from the clear-cell adenocarcinoma of the vagina which occurs after puberty in adolescent girls and young women, and is induced by stilbestrol therapy to the mother during early pregnancy.

Adenocarcinoma↗

PubMed1979

The development of hepatogenic potency in the endoderm of quail embryos.

Hepatogenic potency of the endoderm is detectable in the anterior half of the endoderm of quail embryos older than 2-somite stage when endodermal fragments are cultured with or without heterologous chick mesenchymes, in the coelomic cavity of 3-day chick embryos. On the other hand, the posterior half of the endoderm never has hepatogenic potency. The hepatogenic potency of the endoderm is gradually stabilised with increasing age. However, expression of hepatogenesis can be affected when the endoderm is associated with inductively active digestive tract mesenchymes. Mesenchyme taken from the presumptive cardiac region ('cardiac' mesenchyme) of chick embryos is necessary for the uncommitted anterior endoderm to acquire hepatogenic potency, and this effect is specific for the 'cardiac' mesenchyme. The 'cardiac' mesenchyme, however, fails to induce hepatic epithelium in the allantoic endoderm, which can differentiate heterotypically when cultured in combination with digestive tract mesenchymes. The evidence presented in this study suggests that the effect of 'cardiac' mesenchyme on the acquisition of hepatogenic potency in the endoderm is limited.

Animals↗

PubMed1979

Structure of the endodermal epithelium of the chick yolk sac during early stages of development.

The structure of the areas pellucida and vasculosa of the early chick embryo (stages 11-29) was examined by light, transmission and scanning electron microscopy. The most striking feature of the endodermal cells of these areas is the presence of large intracellular yolk drops which are characteristic of the regions in which they are found; lipid-like homogeneous drops in the area pellucida, heterogeneously composed pleomorphic drops in the mid-region of the area vasculosa and granular drops at the periphery of the area vasculosa in the region of the sinus terminalis. On morphological criteria it is postulated that granular drops may arise by direct engulfment of extracellular yolk, but this does not appear to be true for pleomorphic or homogeneous drops. Since the apical junctions between endodermal cells across the yolk sac are tight, they seal off the extraembryonic compartment from the vitelline circulation and presumably prevent intercellular passage of the yolk constituents. Thus the endodermal epithelium must mediate the transport of nutrients from the yolk mass to the developing embryo. Endodermal cells exhibit a variation across the yolk sac in the presence and number of structures associated with uptake of extracellular materials. The mid-region of the area vasculosa appears to be the most endocytotically active region with an abundance of microvilli, bristle-coated pits and vesicles and apical canaliculi and vacuoles. There is a close association between the endoderm and vitelline blood vessels and this association is maintained, as the yolk sac develops, by the formation of small vessels juxtaposed between the vascular surface of the endoderm and the walls of the large vitelline vessels.

Animals↗

PubMed1977

Segregation during cleavage of a factor determining endodermal alkaline phosphatase development in ascidian embryos.

Localized alkaline phosphatase activity (EC 3.1.3.1) develops progressively in endodermal tissues of the presumptive digestive system in Ciona intestinalis embryos. It was first detected histochemically at late gastrulation, and a puromycin sensitivity period coincident with this time suggests that new alkaline phosphatase is synthesized. Embryos in which cell division was blocked with cytochalasin B at early cleavage stages up to the 64-cell stage, eventually differentiated strong alkaline phosphatase activity in certain cells at each cleavage-arrested stage. The maximum cell numbers and their positions were identical to those of the previously known endodermal cell lineage. Actinomycin D did not prevent development of endodermal alkaline phosphatase when administered from fertilization onwards, nor did other inhibitors of RNA synthesis (chromomycin A3, cordycepin, and daunomycin). There is probably a preformed maternal mRNA for endodermal alkaline phosphatase present in the unfertilizec Ciona egg. Either this RNA itself, or some related translation factor, is localized in the egg cytoplasm and segregated during early cleavages into the endodermal cell lineage of the embryo.

Acetylcholinesterase↗

PubMed1979

Fine structural analysis of the effect of trypan blue on the visceral endoderm of the mouse egg cylinder.

The effects of a maternal injection of trypan blue on primitive streak mouse embryos were studied with electron microscopy. Commercial trypan blue was purified by descending paper chromatography, and pregnant females received an intraperitoneal injection of the collected blue fraction on the evening of the 7th day of gestation. Ultrastructurally, the changes in the visceral endoderm were apparent 10 min after the injection and included an increase in the number of fuzzy-coated vesicles in the apical cytoplasm. By 20 min the apical cytoplasm of the extraembryonic visceral endodermal cells was filled with many fuzzy-coated vesicles and numerous vacuoles of various size and electron density. 30 min after the injection, the extraembryonic visceral endodermal cells were relatively smooth lacking a microvillous border and evidence of endocytic activity was rare. Many embryonic visceral endodermal cells were observed in various stages of degeneration although the underlying embryonic ectoderm appeared unaffected. Morphologically, it appears that trypan blue exerts its first effect by altering the endocytic activity of the visceral endoderm.

Animals↗

PubMed1976

Endodermal sinus tumour of the ovary: a comparative light and electron microscopic study.

An endodermal sinus tumour of the ovary from a 12 year old girl is analysed light- and electron microscopically. The histological appearance is characterized by glandular-papillary structures and microcystic-reticular areas with inclusion of occasional endodermal sinuses. By electron microscopy immature and highly differentiated cells can be distinguished. In analogy to certain structures in the human yolk sac the most differentiated cells in the tumour are regarded as neoplastic endoderm. On the basis of transitional forms between immature and differentiated cells a development of the latter from the former is suggested. The cells in mesenchyme-like areas differ from those of solid and glandular parts merely in the degree of cytoplasmic differentiation but are otherwise believed to represent the same "cell line". In addition to other possible cell functions the cytoplasmic features of the differentiated cell indicates a protein synthesis and secretion. From our observations it is concluded that the endodermal sinus tumour originates from germ cells and differentiates into yolk sac endoderm. The ultrastructural differences between this tumour and clear cell carcinomas of the ovary are discussed.

Cell Membrane↗

PubMed2025

Enhancer remodeling by OTX2 directs specification and patterning of mammalian definitive endoderm.

The molecular mechanisms that drive essential patterning events in the mammalian embryo remain poorly understood. Analysis of transcription factor expression kinetics at peri-gastrulation stages of development suggest Otx2 as a candidate regulator of the definitive endoderm, the precursor of all gut-derived organs. Accordingly, timed OTX2 depletion in gastruloids or during directed differentiation results in abnormal definitive endoderm specification in mouse and human, characterized by altered expression of components and transcriptional targets of the canonical WNT signaling pathway, perturbed adhesion and migration programs, and de-repression of regulators of other lineages. These defects cumulate in impaired foregut formation. Mechanistically, OTX2 is required to activate a subset of endoderm-specific enhancers and to suppress select enhancers of other lineages, allowing timely exit from the primitive streak and correct specification of anterior endoderm. Our results establish OTX2 as an early gut regulator and suggest molecular principles underlying spatiotemporal cell identity conserved across germ layers and species.

Otx Transcription Factors↗

PubMed1979

Freeze-fracture observations on the visceral yolk sac placenta of rats, mice and hamsters. With special reference to endodermal cell tight junctions.

Freeze-fracture replicas of visceral yolk sac from rats, mice and hamsters in late stages of gestation were studied by electron microscopy. Special attention was directed toward determining the types of junctional specializations that exist between the columnar endoderm cells of this placental membrane. In all three species, well-developed, zonular tight (occluding) junctions were found on the contiguous lateral surfaces of the endoderm cells. The tight junctional network, located in an immediate subluminal position, was from 0.2--0.5 micrometers in depth and consisted at any point of 2--5, interconnecting, approximately 9 eta wide, strands (P-face) or shallow furrows (E-face). Patch-like aggregations of irregular intramembrane particles, characteristic of desmosomes (maculae adherentes), also were observed at scattered sites below the tight junctions. However, no evidence of gap (communicating) junctions was encountered. The endoderm cells of the rodent visceral yolk sac have been shown to play a central role in the selective transport of macromolecular substances from the maternal to the fetal system. Tight junctions may be vital to this endodermal cell function by preventing random paracellular fluxes of macromolecules.

Animals↗

PubMed1979

Gap and septate junctions in the excitable endoderm of Polyorchis penicillatus (Hydrozoa, Anthomedusae).

The morphological basis of impulse conduction in a jellyfish epithelium was investigated. Lanthanum impregnation of endodermal canal and endodermal lamella verified the existence of true gap junctions in Polyorchis. In both transverse and en face sections of gap junctions, electron-lucent globules, with a width of 7--8 nm and a spacing of about 11 nm, are evident. Gap-junctions are concentrated at the peripheral canal margin and septate junctions are localized around the canal lumen. Epithelial cells of the endodermal canals are capable of conducting a non-decrementing action potential. It is suggested that endodermal spike propagation, which can mediate 'crumpling' behaviour, is dependent upon low-resistence ionic pathways provided by gap-junctions and upon sealing of the intercellular space from saline extracellular fluids by septate junctions.

Action Potentials↗

PubMed1979

An analysis of the aggregation and morphogenesis of area opaca endoderm cells from the primitive-streak chick embryo.

The aggregative behaviour and subsequent morphogenesis of extra-embryonic endoderm cells from primitive-streak chick embryos have been investigated. A relatively pure population of area opaca endoderm cells was obtained by differential dissociation, which involves partial separation of epiblast and endoderm cell clumps by sieving through Nitex mesh. For aggregation studies cells were cultured in rotating flasks in Leibovitz (L-15) medium, in saline or in saline supplemented with glucose (1 mg/ml). Aggregation was monitored using the Coulter Counter. In these three media aggregation is rapid; by 10 min an average of 61% of the population had aggregated, to reach a plateau at 30 min when an average percent adhesion value of 83% was obtained. The aggregates in L-15 medium were large and compact. After several days in culture, they cavitated and formed smooth hollow vesicles with thin walls composed of one or a few cell layers. Aggregates formed in PCS were smaller and looser in appearance; the addition of glucose resulted in a certain degree of compaction. Some morphogenesis occurred under these conditions with the aggregates developing numerous irregular cavities. These experiments suggest that some of the factors that affect cell adhesion in early embryonic cells can be studied in vitro. The results also indicate that the ability to cavitate is an intrinsic property of the endoderm cells of the area opaca since this occurs in the absence of epiblast or mesoderm.

Animals↗

PubMed1978

Presence of common surface antigens(s) on endodermal tumors and embryonal tissues of rats, hamsters and mice.

Antiserum against yolk-sac carcinoma of rat was prepared in rabbits. After appropriate absorption in vitro or in vivo this antiserum was examined on different tumors and normal tissues or rat, hamster and mouse. The methods used were indirect immunofluorescence and indirect immunoperoxidase staining and cytotoxicity tests. The immune serum was found to react with the cell membrane of different rat and hamster yolk-sac carcinomas. It reacted also with the cell surface of rat hepatoma cells. By absorption on hyalin and blocking with amniotic fluid it was shown that the antigen was neither a basement membrane component nor alpha-fetoprotein. The antiserum was cytotoxic to yolk-sac carcinoma and hepatoma cells. The immune reaction was limited to the cell membrane, as observed in immunofluorescence and in immunoperoxidase staining. The specificity of the antiserum was proved by cross-absorptions with various tumor lines and by removing its activity with the soluble fraction of yolk-sac carcinoma cells. Non-endodermal rat and hamster tumor lines did not react with the anti-yolk-sac carcinoma immune serum. Most normal adult tissues, including spermatozoa, were negative, but a positive reaction was observed in ovaries and on glandular cells of the uterus. In embryonal tissues this surface antigen(s) was detected in the endoderm of 8-day-old rat embryos 7-day-old mouse embryos and in yolk-sac endoderm of both species. The data indicate that the antigen(s) is associated with endodermal differentiation.

Animals↗

PubMed1978

Alpha-fetoprotein, prealbumin, albumin, alpha-1-antitrypsin and transferrin as diagnostic and therapeutic markers for endodermal sinus tumors.

According to Gitlin, alpha-fetoprotein (AFP), albumin, prealbumin, alpha-1-antitrypsin and transferrin are normal products of the human yolk sac. They are expected to reappear in human endodermal sinus tumor (yolk sac tumor). The synthesis of alpha-fetoprotein and other serum proteins by human endodermal sinus tumor was studied in the culture cells and in the tumor tissue transplanted into nude mice. The results gave evidences of synthesis of some of these proteins including alpha-fetoprotein and alpha-1-antitrypsin. Serum concentrations of these proteins were studied in eight children having endodermal sinus tumors. Serum AFP levels were abnormally high in all cases, whereas concentrations of other serum proteins were almost within normal ranges. This might be simply reflected by the fact that pre-albumin, albumin, alpha-1-antitrypsin, and transferrin are already present in large quantities in sera of normal subjects while alpha-fetoprotein is present only in a negligible quantity. Alpha-fetoprotein, as a diagnostic and therapeutic marker of endodermal sinus tumor, showed good correlation to the tumor growth. Serum AFP concentrations declined almost to 0 ng/ml with a half-life of 4 days when surgical removal was complete, whereas serum AFP decreased only to 100-200 ng/ml with radiation and chemotherapy alone.

Adolescent↗

PubMed1979

Endodermal sinus tumor of the ovary. Clinicopathologic study of 6 cases.

6 cases of endodermal sinus tumor of the ovary are presented. In 4 patients pure endodermal sinus tumor was found microscopically. 1 patient had endodermal sinus tumor in one ovary and gonadoblastoma in the contralateral one. In another case endodermal sinus tumor was accompanied by an embryonal teratoma. Histologically, the tumor had characteristic features with meshwork of spaces and channels lined by embryonal cells, glomerulus-like structures known as Schiller-Duval bodies, solid aggregates of epithelial cells, hyaline basement membranes and round, PAS-positive small globules found both intra- and extracellulary. In 1 patient the elevated serum alpha-fetoprotein was stated. All patients were treated surgically with adjunctive radiation and/or with chemical agents. None of them were cured. The median duration of survival amounted to 8.5 months. Discussing the value of the more recent approach to diagnostic and therapeutic methods found in the literature, it must be emphasized that the demonstration of elevated serum alpha-fetoprotein in patient with that tumor lend not only further support to its yolk sac origin but also might be useful to monitor response to the therapy applied. It is also of prognostic significance by indicating the presence of residual or recurrent disease, even in its subclinical stage. Combined postoperative irradiation and triple chemotherapy according to the VAC regimen of patients can prevent recurrence and in some cases even may cause permanent remission of the neoplasm.

Adolescent↗

PubMed2024

The scramblases VMP1 and TMEM41B are required for primitive endoderm specification by targeting WNT signaling.

The ER-resident proteins VMP1 and TMEM41B share a conserved DedA domain, which confers lipid scramblase activity. Loss of either gene results in embryonic lethality in mice and defects in autophagy and lipid droplet metabolism. To investigate their role in pluripotency and lineage specification, we generated Vmp1 and Tmem41b mutations in mouse embryonic stem cells (ESCs). We observed that ESCs carrying mutations in Vmp1 and Tmem41b show robust self-renewal and an unperturbed pluripotent expression profile but accumulate LC3-positive autophagosomes and lipid droplets consistent with defects in autophagy and lipid metabolism. ESCs carrying combined mutations in Vmp1 and Tmem41b can differentiate into a wide range of embryonic cell types. However, differentiation into primitive endoderm-like cells in culture is impaired, and the establishment of extra-embryonic endoderm stem (XEN) cells is delayed. Mechanistically, we show the deregulation of genes that are associated with WNT signaling. This is further confirmed by cell surface proteome profiling, which identified a significant reduction of the WNT-receptor FZD2 at the plasma membrane in Vmp1 and Tmem41b double mutant ESCs. Importantly, we show that transgenic expression of Fzd2 rescues XEN differentiation. Our findings identify the role of the lipid scramblases VMP1 and TMEM41B in WNT signaling during extra-embryonic endoderm development and characterize their distinct and overlapping functions.

Animals↗

PubMed1977

[Induction of the mesoderm and primordial germ cells by the endoderm of Pleurodeles waltlii (Amphibia, Urodele): development during gastrulation].

Blastulae ectoderm is combined with dorsal or ventral endoderm from blastulae, gastrulae and early neurulae. In vitro culture reveals the presence of different mesodermal structures whose nature is connected with the endoderm origin site. Primordial germ cells differentiate essentially in the recombinates including ventral endoderm. The inducing capacity of this latter concerning germ cells is maximum at the beginning of gastrulation, then decreases during it and finally disappears at the onset of neurulation.

Age Factors↗

PubMed1976

Serum alpha-fetoprotein as a marker for the effect of post-operative radiation therapy and/or chemotherapy in eight cases of ovarian endodermal sinus tumour.

The clinical pathological findings of eight cases of ovarian endodermal sinus tumour (yolk sac tumour) are presented. Histological exmination in all eight cases showed a typical endodermal sinus tumour pattern, and in six of the patients other tumour elements such as dysgerminoma, choriocarcinoma, malignant teratoma, endometriosis, and a dermoid cyst were also found. Six patients had increased serum alpha-fetoprotein concentration in the post-operative period, and two patients had a normal concentration 27 and 35 days after operation, respectively. In all cases except one, a close correlation between serum alpha-fetoprotein and progression or regression of tumour was found. Serum alphafetoprotein was thus found to be a reliable parameter in post-operative radiation and/or chemotherapy (VAMBLE). In one patient who died 10 months after operation with widespread endodermal sinus tumour growth, only a small terminal increase in serum alpha-fetoprotein concentration was found. Four of the eight women are still alive with normal alpha-fetoprotein concentration, and without clinical evidence of tumour disease.

Adolescent↗

PubMed1977

Alpha-1 antitrypsin (AAT) and alphafoetoprotein (AFP) in sera of patients with germ-cell neoplasms: value as tumour markers in patients with endodermal sinus tumour (yolk sac tumour).

Serum alphafoetoprotein (AFP) and serum alpha-1 antitrypsin (AAT) were determined in 24 patients with germ-cell neoplasms of the gonads and extragonadal sites and in two patients with hepatocellular carcinoma. In the majority of the patients serial determinations were performed. All seven patients with testicular seminoma and four patients without evidence of active disease had normal levels of serum AAT and AFP. The remaining 13 patients with germ-cell neoplasms had tumours containing endodermal sinus tumour (yolk-sac tumour) elemetns. All these 13 patients had elevated levels of serum AFP and the levels were high or very high in most cases. Nine of these 13 patients had raised serum AAT, although the elevation above normal levels was only slight in a number of cases. When serial determinations were performed serum AAT levels frequently followed the pattern of serum AFP levels, but the AAT levels were frequently within normal limits and therefore the interpretation of the results was difficult, and much less reliable as compared with those for serum AFP. The elevation of serum AAT levels following the recurrence of the tumour was found to occur much later and was much less marked than elevation of serum AFP, which occurred early, showed a large rise and was a reliable marker of tumour recurrence in patients with germ-cell neoplasms containing endodermal sinus tumour elements. 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. Serum AAT may be a useful tumour marker in patients with hepatocellular carcinoma, and this aspect should be investigated further.

Adolescent↗

PubMed1976

Alpha1-antitrypsin and alpha-fetoprotein. Protein markers in endodermal sinus (yolk sac) tumors.

A combined immunocytochemical and quantitative serum and tissue study was performed on a group of endodermal sinus (yolk sac) tumors, localizing and measuring both alpha1-antitrypsin (AAT) and alpha-fetoprotein (AFP) in tumor tissue and patient sera. Utilizing indirect immunofluorescent and triple-sandwich immunoperoxidase methods, both proteins were demonstrated within intra- and extracellular periodic acid-Schiff-positive hyaline globules characteristic of the tumor, as well as within the cytoplasm of tumor epithelial cells lining endodermal sinuses, where AAT deposition predominated. Tumor tissue extracts confirmed the presence of significant quantities of both proteins, and pretreatment serum elevations of both showed a parallel decline during therapy. In this study, AAT is characterized as a tumor protein marker for the first time, and a parallelism between AAT and AFP is demonstrated in both serum and tumor tissue. These findings represent additional supportive evidence for the yolk sac origin of endodermal sinus tumors in man.

Child↗