Malignant germ-cell tumors (MGCT) are rare tumors of childhood accounting for less than 3% of pediatric malignancies. Yolk sac (endodermal sinus) tumor is one of the malignant germ cell tumor that usually involves the gonads (ovaries and testes). Its occurrence in the vagina is extremely rare. We report a 6-months old girl presented with a vaginal mass diagnosed as a yolk sac tumor. This diagno...

Multiplication of Toxoplasma gondii was examined in vitro in murine erythroid cells at different stages of development. Toxoplasma gondii multiplied in nucleated erythroblasts and enucleated reticulocytes from the foetal liver, and in immature reticulocytes and yolk-sac derived erythrocytes from the foetal circulation. However, the rate of multiplication was lowered as erythroblasts matured, an...

We describe a rare case of pulmonary blastoma complicated with systemic sclerosis. The serum alpha-fetoprotein level was elevated at presentation and the biopsied tumour stained positively against anti-alpha-fetoprotein antibody. The alpha-fetoprotein produced autonomously by tumour cells was of yolk-sac origin. Although the pathogenesis of pulmonary blastoma has not been clarified, we suggest ...

In this report we present a case ofprimary yolk sac tumour of the anterior mediastinum in which two dimensional echocardiography showed an extracardiac mass simulating a large pericardial effusion. Mediastinal yolk sac tumour is a rare germ cell neoplasm affecting mainly young men.' The most common presenting symptoms are dyspnoea, cough, and chest pain.2 The prognosis is usually poor, though i...

Malignant germ-cell tumors (MGCT) are rare tumors of childhood accounting for less than 3% of pediatric malignancies. Endodermal sinus tumor (EST) forms the most common histologic subtype of MGCT. The vagina is an extremely rare site for GCTs. An 8-month-old female was admitted with a short history of vaginal bleeding, and a mass protruding from the vagina. She was pale and a mass was palpable ...

We have studied both in vitro and in vivo the formation of lymphocyte progenitors before blood circulation (day 9 of gestation) has started in the mouse embryo, and we have determined the tissue where this occurs. The results demonstrate that the yolk sac of embryos at day 8 and day 8.5 of gestation contains precursor cells that can give rise, in vivo and in vitro, to mature T and B lymphocytes...

The platelet glycoprotein IIb (alpha(IIb); CD41) constitutes the alpha subunit of a highly expressed platelet surface integrin protein. We demonstrate that CD41 serves as the earliest marker of primitive erythroid progenitor cells in the embryonic day 7 (E7.0) yolk sac and high-level expression identifies essentially all E8.25 yolk sac definitive hematopoietic progenitors. Some definitive hemat...

and could be read with profit by anyone interested in the problem of hydramnios. The Morphologic Manifestations of Uptake of Materials by the Yolk Sac of the Pregnant Rabbit describes how colloidal gold, erythrocytes, cream, and protein, in the form of egg white, are absorbed by the yolk sac. There are several electron microphotographs which are used to illustrate some of the processes. The Dev...