Transforming growth factor β1 (TGFβ1) is shown here to be required for yolk sac haematopoiesis and endothelial differentiation. Mice with a targeted mutation in the TGFβ1 gene were examined to determine the cause of prenatal lethality, which occurs in 50% of homozygous TGFβ1 null (TGFβ1−/−) conceptions. 50% of TGFβ1−/− and 25% of TGFβ1+/− conceptuses were found to die at around 10.5 dpc. The pr...

To examine the influence of the hematopoietic microenvironment on hematopoietic cell proliferation and differentiation during the yolk sac phase of hematopoiesis, we have recently established cell lines from embryonic yolk sac visceral endoderm (YSE) and mesoderm (YSM). In the present experiments, we compared in vitro growth of adult murine bone marrow high proliferative potential colony-formin...

BACKGROUND Cardiac involvement by a malignant tumor is rare. However, this is a case of right heart failure due to cardiac metastasis from a yolk sac tumor. Although a few case reports of cardiac metastasis from yolk sac tumors have been published, to our knowledge this is the first instance of multiple metastases to the right ventricular of yolk sac tumor in an adult male. CASE REPORT The pati...

The embryonic origin and development of hematopoietic and endothelial cells is highly interdependent. We hypothesized that primary endothelial cells from murine yolk sac and para-aortic splanchnopleura (P-Sp) may possess the capacity to expand hematopoietic stem cells (HSCs) and progenitor cells ex vivo. Using Tie2-GFP transgenic mice in combination with fluorochrome-conjugated monoclonal antib...

In adults, the nonclassical MHC class I molecule, FcRn, binds both IgG and albumin and rescues both from a degradative fate, endowing both proteins with high plasma concentrations. FcRn also transports IgG from mother to young during gestation. Anticipating that a detailed understanding of gestational IgG transport in the mouse may give us a useful model to understand FcRn function in the human...

BACKGROUND To describe 19 years of clinical experience managing pediatric patients with testicular yolk sac tumors at the Chongqing Medical University Affiliated Children's Hospital. METHODS This study involved a retrospective review of the records of 61 pediatric patients who presented with testicular yolk sac tumor at our institution between 1995 and 2014. RESULTS All patients presented w...

Tropomodulin (Tmod)1 caps the pointed ends of actin filaments in sarcomeres of striated muscle myofibrils and in the erythrocyte membrane skeleton. Targeted deletion of mouse Tmod1 leads to defects in cardiac development, fragility of primitive erythroid cells, and an absence of yolk sac vasculogenesis, followed by embryonic lethality at embryonic day 9.5. The Tmod1-null embryonic hearts do not...

With the use of immunohistochemical techniques, seven mouse monoclonal antibodies and the lectin from Ulex europaeus, detecting blood group antigens of the ABH and Lewis systems, have been used to define the distribution of these antigenic structures in germ cell tumors. The reagents used recognize the following blood group antigens: A, B, H, Lewisa, Lewisb, X (Lewisx), Y (Lewisy), and type I p...

BACKGROUND This study was undertaken to determine if there were different abortion rates between normal and abnormal yolk sacs. MATERIALS AND METHODS In this cohort study, the yolk sac characteristics of 193 consecutive pregnant women, of 5-6.5 weeks gestation, with normal body mass index (BMI) were prospectively evaluated. All patients underwent two-dimensional transvaginal ultrasonography, ...

Embryonic hematopoiesis is initiated in part in the blood islands of the yolk sac. Previous confocal microscopic analysis has shown that the CD34 antigen, a mucin-like cell surface glycoprotein that is expressed by hematopoietic progenitors and all endothelial cells of the adult and embryo, is also found on a subset of luminal hematopoietic-like cells in the yolk sac blood islands as well as on...