Expression of an antigen, recognized by a monoclonal antibody raised against PC13 embryonal carcinoma, is described in mouse preimplantation embryogenesis. The antigen is found in the cytoplasm of ovulated ova and is first noted on the cell surface of the 1-cell embryo 20 h post-ovulation. Surface labelling of blastomeres is uniform until the 8-cell stage when antigen expression becomes polariz...

Spinocerebellar ataxia 3 (SCA3) is an autosomal dominant neurodegenerative disorder characterized by variable expression and a variable age of onset. SCA3/MJD (Machado-Joseph disease) is caused by an expansion of a (CAG)(n) repeat in the MJD1 gene on chromosome 14q32.1. A single cell PCR protocol has been developed for preimplantation genetic diagnosis (PGD) of SCA3 to select unaffected embryos...

Not only a whole denuded egg, but also blastomeres isolated from 2-, 4- and 8-cell starfish embryos developed into morphologically normal, but dwarf bipinnariae, the sizes of which were roughly proportionate to that of the respective original blastomeres. Some of the blastomeres isolated from the 16-cell stage were also capable of developing into the larval stage. All isolated blastomeres divid...

Two successive inductions specify blastomere identities, that is complex cell lineages and not specific tissues, in a major part of the early C. elegans embryo. The first induction acts along the anterior-posterior axis of the embryo and the second along the left-right axis. During the first induction a specific lineage program is induced in the posterior of the two AB blastomeres present in th...

Gaining knowledge about the physiological timetable of gene expression during preimplantation embryo development is crucial, and a better understanding of cytokine and growth factor expression in early embryonic development could lead to improved in vitro culture conditions and enhance in vitro fertilization implantation rates. Our aim was to detect the patterns and levels of two messenger ribo...

Background: In vitro culture of mammalian embryos can slow or stop growth completely. This may be due to the medium used, pH, temperature, or light. There is considerable concern about the harmful effect of light in the laboratory environment. Cell number and apoptosis are useful parameters that indicate embryonic development and health. In this study, we assessed these two factors in the blas...

clinical reproductive centers produce large amounts of surplus poor-quality embryos annually, how to maximize the use of these embryos, and which of them have the potential to develop into blastocyst stage and influencing factors were lack of systematic research. objective: to investigate the fate of surplus poor-quality embryos which were cultured to obtain blastocyst, determine the factors wh...

We have further analysed the roles of mesoderm induction and dorsalization in the formation of a regionally specified mesoderm in early embryos of Xenopus laevis. First, we have examined the regional specificity of mesoderm induction by isolating single blastomeres from the vegetalmost tier of the 32-cell embryo and combining each with a lineage-labelled (FDA) animal blastomere tier. Whereas do...