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At least 523 records · Page 29Linked to original sources
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↗
PubMed1982

[Electron microscopic study of in vitro differentiation of the small intestinal endoderm in young bird embryo in the presence or absence of mesenchyme].

Electron microscopical studies demonstrated that the small intestinal endoderm of young avian embryos cultures in vitro in the presence or absence of mesenchyme can differentiate into an absorptive epithelium with the brush border, and that, in the absence of mesenchyme the brush border develops much earlier than in the presence of mesenchyme, but goblet cells do not appear and morphogenesis of villi does not occur. These results show that the intestinal mesenchyme controls the endodermal differentiation, though the undifferentiated endoderm possesses self-differentiation potency.

Animals↗
PubMed1984

Apolipoprotein expression by murine visceral yolk sac endoderm.

Apolipoprotein expression was examined in the postimplantation mouse embryo. Antibodies directed against murine Apolipoprotein AI and human low-density lipoprotein (LDL) particles specifically immunoprecipitated metabolically labelled radioactive apolipoproteins from the culture supernatant of 10.5 days post coitum (days p.c.) yolk sac visceral endoderm cultured in vitro. No evidence for apolipoprotein expression by other embryonic or extraembryonic tissues at this stage was obtained. Immunohistochemical staining at sectioned 10.5 days p.c. embryos with anti-Apolipoprotein AI antibodies revealed specific localization of immunoreactive material in the yolk sac visceral endoderm. We conclude that the yolk sac visceral endoderm is a source of lipoproteins during postimplantation embryonic development.

Animals↗
PubMed1980

The migration of presumptive primordial germ cells through the endodermal cell mass in Xenopus laevis: a light and electron microscopic study.

Presumptive primordial germ cells (pPGCs) were examined during migration from their deep endodermal position to the endodermal crest in Xenopus laevis, using light and electron microscopy with Epon sections, and several morphological characteristics of pPGCs, associated with their migration, were revealed. pPGCs displayed polymorphism, with smooth contours. The intercellular space around the PGCs was large and variable in width and cytoplasmic processes from pPGCs were occasionally observed in it. It was shown quantitatively that pPGCs at the migratory stage had a tendency to move with the leading end, towards which the nucleus was localized, dragging the germinal plasm behind. These polarized pPGCs were frequently associated with large intercellular spaces, both at their leading and trailing ends. Cytoplasmic processes of polarizing pPGCs found in the large intercellular space at the leading end were conspicuous. Ultrastructurally, the nuclei of pPGCs were euchromatic, and the nucleolus was prominent. The germinal plasm at the light microscope level corresponded to the cytoplasmic area near the nucleus where a large number of mitochondria with well-developed cristae and most of the other organelles were aggregated. Centrioles and centriole-associated microtubules observed in the aggregate were thought to be important structures responsible for the cell polarization mentioned above. It was demonstrated quantitatively that the size of mitochondria in pPGCs was larger on average than that of mitochondria in neighbouring somatic endodermal cells. Numerous irregularly shaped small yolk platelets characterized pPGCs. These ultrastructural features suggested that pPGCs were in an activated metabolic state. It was concluded that the migration of pPGCs was attributable to active movement with high cell metabolism, causing the formation of cell processes and intracellular polarization.

Animals↗
PubMedDate not supplied

Thymus development in amphibians: colonization by thymic endodermal rudiments by lymphoid stem-cells of mesenchymal origin in the urodele Pleurodeles waltlii Michah.

Pleurodeles waltlii thymus morphogenesis was studied by serial semi-thin sections and by electron microscopy. Thymus endodermal buds were first seen 9 days after fertilization. From 12 to 16 days, these rudiments are invaded by a small number of cells moving from the cephalic mesenchyme environment. These cells have the ultrastructural morphology of lymphoid stem-cells. Cytologic transitional forms from endodermal to lymphoid-like cells are never observed. These results clearly indicate that in amphibians the thymus lymphocytes are not derived from the initial endodermal rudiments.

Animals↗
PubMed1987

Endodermal sinus tumor (yolk sac tumor) of the ear.

Endodermal sinus tumors (yolk sac tumors) are malignant germ cell tumors that usually arise in the gonads. We report what is, to our knowledge, the first known case of an endodermal sinus tumor of the ear. The tumor was present in a developmentally delayed child with an abnormal temporal bone and exhibited histopathologic and immunocytochemical features identical to those of endodermal sinus tumors of gonadal origin. The tumor resolved after chemotherapy, and the patient remained alive without evidence of disease at the time of this writing. The purpose of this report is to add a rare tumor to the differential diagnosis of neoplasms of the ear in children and to familiarize otorhinolaryngologists and head and neck surgeons with its pathologic features and clinical management.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1976

Endodermal sinus tumor of the pineal region: case report.

This is a case report of an endodermal sinus tumor occurring in the pineal region of a 12-year-old Caucasian boy. Germ cell tumors of this type demonstrate a selective overgrowth of yolk sac endoderm associated with extraembryonic mesoblast and arise perferentially in the gonads of young children. This is the ninth known report of this tumor in the world literature. Its occurrence in the posterior third ventricle again confirms that pineal region germ cell tumors are histologically analogous to germ cell tumors originating in the gonads. A disturbance in the region of the primitive streak is thought to account for the exclusive midline location of this tumor in extragonadal sites. This patient was treated with a combination of vincristine, actinomycin D, and cyclophosphamide, and concomitant cobalt irradiation. For endodermal sinus tumors in the pineal region, this combination appears more effective than previously reported treatment by irradiation alone.

Adolescent↗
PubMed1981

Successful treatment of metastatic extragonadal endodermal sinus (yolk sac) tumor in childhood.

Two children with metastatic extragonadal endodermal sinus tumor who had failed VAC chemotherapy were treated with combination chemotherapy consisting of cis-platinum, vinblastine, doxorubicin HCl (Adriamycin) and bleomycin (cis-VAB). There was a complete response in both patients with one child remaining tumor-free 3 1/2 years after metastasis and 2 1/2 years after stopping therapy. The main toxic reactions encountered were associated with the use of cis-platinum, but these were manageable and resolved upon completion of therapy. Cis-VAB appears to be a safe and effective regimen for the treatment of metastatic endodermal sinus tumor. A study of the efficacy of cis-VAB in a larger group of children with endodermal sinus tumor of poor prognosis seems indicated.

Adolescent↗
PubMed1986

Endodermal sinus tumor of the mediastinum. A report of seven cases and review of the literature.

Primary mediastinal endodermal sinus tumor is rare, and to date only 49 cases have been described in the English-language literature. Seven new cases are reported. Light microscopic examination showed characteristic features including papillary, reticular, tubular and solid growth patterns, complete or incomplete Schiller-Duval bodies and intracellular or extracellular periodic acid-Schiff-positive material. Immunohistochemical studies showed alpha-1-antitrypsin in seven, alpha-fetoprotein in seven, keratin in six, and carcinoembryonic antigen in four cases. The beta subunit of human chorionic gonadotropin, albumin, fibronectin, and transferrin were not found in any case. Electron microscopic studies performed in four cases showed intracellular and extracellular basement membrane-like material, multiple large multivesicular bodies, desmosomes and microvilli. Mediastinal endodermal sinus tumor can and must be differentiated from poorly differentiated adenocarcinoma metastatic or extending to the mediastinum because of the distinctly different prognoses and therapies. In spite of modern chemotherapy, the prognosis of mediastinal endodermal sinus tumor remains poor. The single most important prognostic indicator is whether the tumor mass can be completely excised before or after chemotherapy.

Adolescent↗
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↗
PubMed1993

Endodermal sinus tumor of the vagina in an infant: magnetic resonance imaging evaluation.

Endodermal sinus tumor is a rare and highly malignant lesion. This report documents the clinical findings and magnetic resonance imaging (MRI) of an uncommon case of the endodermal sinus tumor arising in the vagina of a 6-month-old infant. MRI was extremely accurate in delineating the possible extent and location of the vaginal lesion. This is the first report to demonstrate MRI of vaginal endodermal sinus tumor.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Primary endodermal sinus tumor of the liver detected by CT.

We report a case of primary endodermal sinus tumor of the liver. Endodermal sinus tumors are rare neoplasms which usually arise in the testis or ovary. Extragonadal endodermal sinus tumors are uncommon and primary tumors of the liver are very rare. The tumor was detected using CT and the diagnosis was made by percutaneous biopsy.

Female↗
PubMed1981

Ultrastructure and immunohistochemical staining of a transplanted endodermal sinus tumor.

An endodermal sinus (yolk sac) tumor was successfully transplanted into athymic nude mice. Histologic and ultrastructural investigations revealed that the transplanted tumor had a characteristic appearance with numerous Shiller-Duval bodies, endodermal sinus structures and ultrastructural profiles as previously described in human material. The endodermal sinus tumor and normal human yolk sac have been found to synthesize not only alpha-fetoprotein (AFP), but also other serum proteins, namely, albumin, prealbumin, alpha 1-antitrypsin, and transferrin. Serological study by radioimmunoassay demonstrated AFP, carcinoembryonic antigen (CEA) and human chorionic gonadotropin (HCG) in the sera of the tumor-bearing nude mice and in cyst fluid from the transplanted tumor. Immunohistochemical investigation using the unlabeled antibody peroxidase-antiperoxidase method showed using the unlabeled antibody peroxidase-antiperoxidase method showed that the tumor cells produced CEA, alpha 1-antitrypsin, transferrin, HCG as well as AFP. These immunohistochemical staining properties were correlated with the findings on radioimmunoassay.

Adult↗
PubMed1999

Fourier transform infrared-spectroscopic characterisation of isolated endodermal cell walls from plant roots: chemical nature in relation to anatomical development

The chemical nature of enzymatically isolated endodermal cell walls from Cicer arietinum L., Clivia miniata Reg. and Iris germanica L. was studied by FTIR (Fourier transform infrared) spectroscopy. Observed frequencies were assigned to functional groups present in the cell wall and relative amounts of the biopolymers suberin and lignin, cell wall carbohydrates and proteins were determined. Infrared absorption spectra indicated structural characteristics for the three different developmental states of the isolated endodermal cell wall: primary endodermis with Casparian strips (state I), secondary endodermis with suberin lamellae (state II), and tertiary endodermis with U-shaped cell wall depositions (state III). The data obtained from this study are compared with previous results obtained by chemical degradation of isolated endodermal cell walls and subsequent determination of monomeric degradation products by gas chromatography and mass spectrometry. It is concluded that FTIR spectroscopy represents a direct and nondestructive method suitable for the rapid investigation of isolated plant cell walls. Furthermore, the observation that the suberin-assigned absorption bands disappeared after transesterification of the samples with BF(3)-methanol confirmed that suberin is completely degraded by this treatment.

Journal Article↗
PubMed2006

Unusual presentation of intradural endodermal cysts in young children under 2 years of age. Report of two cases.

INTRODUCTION: Spinal endodermal cysts are congenital maldevelopmental lesions usually presenting in early adulthood. Whereas the diagnosis is rare in newborns and it is usually led by cardiopulmonary distress or other associated malformations, no characteristic clinical findings associated with these entities have been described in older patients where spinal endodermal cysts usually behave as intraspinal space occupying lesions. DISCUSSION: The authors report on two children under 2 years of age affected by cervical endodermal cysts that presented with a history of acute motor deficit following a laryngitis. The hypothesis about the pathogenesis is that the upper respiratory tract infection might have stimulated the secretion of the cyst lining, inducing growth of the cyst and the sudden appearance of the motor deficit. Because of the apparent lack of relation between the benign laryngitis and the motor deficit, the occurrence of such an association might have been underestimated in some of the previously reported cases.

Ataxia↗
PubMed1984

Normal pregnancy and delivery following conservative surgery and chemotherapy for ovarian endodermal sinus tumor.

Management of younger patients with early stage ovarian endodermal sinus tumor who desire to have children can be a challenging problem. However, after an adequate and thorough staging procedure for the patient's tumor status, a Stage Iai endodermal sinus tumor may be treated with conservative surgery only, followed by chemotherapy. Successful pregnancy and delivery following unilateral adnexectomy and chemotherapy for ovarian endodermal sinus tumor have been reported only once [J. P. Forney, Obstet. Gynecol. 52, 360 (1977)]; the second reported case is presented here. It should be pointed out that strict follow-up and reliability of the patient are mandatory for such conservative therapy.

Adult↗
PubMed1988

Radiosensitivity related to neuroendocrine and endodermal differentiation in lung carcinoma lines.

A panel of human lung carcinoma lines was studied with respect to hormone production and intermediate filament expression to distinguish between endodermal and neuroendocrine differentiation. An index of the degree of neuroendocrine differentiation of each line was derived from the presence or absence of hormone production, cytokeratins, neurofilaments and an embryonic endodermal cell marker, which allowed identification of three groups showing high, intermediate or low neuroendocrine expression. This grouping correlated well with the in vitro radiosensitivity of the lines, those expressing pure neuroendocrine features being significantly more radiosensitive than those with an endodermal phenotype, with the intermediate group having intermediate sensitivity. Use of such an index might predict those patients likely to benefit from the use of radiotherapy in their management.

Adenocarcinoma↗