Nanomaterials (NMs) display many unique and useful physico-chemical properties. However, reliable approaches are needed for risk assessment of NMs. The present study was performed in the FP7-MARINA project, with the objective to identify and evaluate in vitro test methods for toxicity assessment in order to facilitate the development of an intelligent testing strategy (ITS).
View Article and Find Full Text PDFThe utilization of neural stem cells and their progeny in applications such as disease modelling, drug screening or safety assessment will require the development of robust methods for consistent, high quality uniform cell production. Previously, we described the generation of adherent, homogeneous, non-immortalized mouse and human neural stem cells derived from both brain tissue and pluripotent embryonic stem cells (Conti et al., 2005; Sun et al.
View Article and Find Full Text PDFObjective: To investigate expression of N- and E-cadherin in the developing human ovary.
Design: The expression of N- and E-cadherin was analyzed in 18 human fetal ovaries between 8 and 20 weeks' gestation using immunohistochemistry. Fetal human male and rat urogenital tracts were used for comparison of expression.
Ovarian germ cell survival is dependent upon the formation of primordial follicles, which occurs during fetal life in the human. Activin contributes to germ cell proliferation and survival at this time. SMADs2 and 3 are central elements in the activin signalling pathway and thus indicate sites of activin action.
View Article and Find Full Text PDFBackground: Germ cells arise from a small group of cells that express markers of pluripotency including OCT4. In humans formation of gonadal compartments (cords in testis, nests in ovary) takes place during the 1st trimester (6-8 weeks gestation). In the 2nd trimester germ cells can enter meiotic prophase in females whereas in males this does not occur until puberty.
View Article and Find Full Text PDFDuring mammalian ovary formation, the production of ovarian follicles is accompanied by an enormous loss of germ cells. It is not known how this loss is regulated. We have investigated the role of the Trk tyrosine kinase receptors, primarily TrkB, in this process.
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