Nuclear transfer was used to study nuclear reprogramming of fetal diploid bovine germ cells collected at two stages of the fetal development. In the first case, germ cells of both sexes were collected during their period of intragonadal mitotic multiplication at 48 days post coïtum (d.p.c.). In the second case, only male germ cells were collected after this period, between 105 and 185 d.p.c. Is...

Cloning mammals by nuclear transfer is a powerful technique that is quickly advancing the development of genetically defined animal models. However, the overall efficiency of nuclear transfer is still very low and several hurdles remain before the power of this technique will be fully harnessed. Among these hurdles include an incomplete understanding of biologic processes that control epigeneti...

The use of nuclear techniques in nutrition adds value by the increased specificity and sensitivity of measures compared with conventional techniques in a wide range of applications. This article provides a brief overview of well-established stable-isotope techniques to evaluate micronutrient bioavailability and assess human-milk intake in breastfed infants to monitor the transfer of micronutrie...

The relationship between the level of cell confluence near the plateau phase of growth and blastocyst yield following somatic cell cloning is not well understood. We examined the effect of distinct cell culture confluence levels on in vitro development of cloned bovine embryos. In vitro-matured bovine oocytes were manually bisected and selected by DNA staining. One or two enucleated hemi-cytopl...

Widespread studies on tumor diagnosis has led to the development of techniques with greater sensitivity and improved specificity for detection of occult and small subclinical tumors. Tumor imaging by radiolabeling of tumor-specific antibodies (Immunoscintigraphy) or tissue specific biochemical agents (Receptor imaging) and especially physiologic imaging with positron emitters (PET), have ...

INTRODUCTION A N important problem in embryology is whether the differentiation of cells depends upon a stable restriction of the genetic information contained in their nuclei. The technique of nuclear transplantation has shown to what extent the nuclei of differentiating cells can promote the formation of different cell types (e.g. King & Briggs, 1956; Gurdon, 1960c). Yet no experiments have s...

A number of animals with genetically identical appearance can be produced by somatic cell nuclear transfer (SCNT). From current advancement of SCNT and molecular techniques, production of a transgenic animal becomes easier. Although cloning efficiency in goat is low, the ability to propagate genetically identical animals, with a gene or genes of interest, would be important for increasing produ...

Tripronuclear human zygotes were used to determine the feasibility of an enucleation procedure without the use of cytoskeleton inhibitors to obtain intact cytoplasts for nuclear transfer research. Of 61 tripronuclear human zygotes manipulated, 100% of the zygotes survived after removal of one pronucleus and 90.1% after complete enucleation, proving the reliability of the proposed microsurgical ...