Conceptuses from 9.5-day pregnant rats were cultured for 48 h in heat-inactivated homologous serum to which leupeptin, a specific inhibitor of the lysosomal cysteine-proteinases, was added for the final or the penultimate 6 h. The presence of leupeptin (25 micrograms/ml or above) increased the protein content of yolk sacs at harvesting to approximately twice the control value. The protein conte...

Yolk retention and yolk sac infection is considered as an important cause of death in chicken as well as in guinea fowl, duck, turkey, quail and goose. The factors which slow down the rate of yolk absorption and may in turn, lead to yolk retention are discussed. Yolk sac infection of bacterial origin is most important among these factors. Other factors which may contribute include posthatch sta...

Gastric adenocarcinoma with yolk sac tumor (YST) differentiation has rarely been reported. We report a case of primary gastric adenocarcinoma with yolk sac tumor differentiation and liver metastases of the YST component in a 50-years-old patient. This was suspected due to high serum level of alpha fetoprotein in the presence of a gastric fundal tumor. Gastric carcinoma with yolk sac tumor compo...

Yolk sac tumor rarely involves the pericardium. A 17-year-old boy had a mediastinal mass leading to total obstruction of the superior vena cava with cardiac tamponade and pleural effusion. Further imaging studies and biopsy showed that the origin was a yolk sac tumor. After surgery and adjuvant chemotherapy, no recurrence was noted during a follow-up of 20 months. This report describes the magn...

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 ...

Mature T cells are derived from prethymic stem cells, which arise at one or more extrathymic sites and enter and differentiate in the thymus. The nature of these prethymic stem cells is a critical factor for the formation of the T-cell repertoire. Although the bone marrow of adult mice can provide such stem cells, their origin during murine embryogenesis is still undetermined. Among potential s...

AIMS The present study aimed to determine whether yolk sacs with abnormal sonographic appearance are associated with adverse perinatal outcomes in both early and late gestation. MATERIAL AND METHODS A total of 305 viable singleton pregnancies with gestational age of 6 to 9 weeks were prospectively evaluated with respect to perinatal outcomes and sonographic characteristics of the yolk sacs. ...