mouse embryos into blastocysts in vitro have been closely examined (Whitten, 1956, 1957; Brinster, 1965a, b, c), and it has been shown that the requirements depend on the stage of development when cultivation begins (Brinster & Thomson, 1966; Biggers, Whittingham & Donahue, 1967). One of the inter¬ esting findings has been that there is no absolute requirement for the essential amino acids eith...

BACKGROUND AND AIMS Sunflower cultivars exhibit a wide range of oil content in the mature achene, but the relationship between this and the dynamics of oil deposition in the achene during grain filling is not known. Information on the progress, during the whole achene growth period, of the formation of oil bodies in the components of the achene and its relationship with variations in final oil ...

Bilateral pairs of blastomeres derived from the founder cell AB, the anterior blastomere of the 2-cell stage, in the Caenorhabditis elegans embryo are initially equivalent in their developmental potential. Recently, we showed that an induction at the 12-cell stage by a blastomere called MS is necessary to establish the differences between left and right pairs of blastomeres in the anterior part...

embryonic stem cells (escs) are undifferentiated cells which are typically derived from the inner cell mass of a blastocyst-stage embryo. in culture, these cells have the capacity to self-renew in an undifferentiated state but also may differentiate into cell types representing the three embryonic germ lineages, thus revealing their pluripotent potential. these cells could be of value for creat...

Although many of the core components of the embryonic cell-cycle network have been elucidated, the question of how embryos achieve robust, synchronous cellular divisions post-fertilization remains unexplored. What are the different schemes that could be implemented by the embryo to achieve synchronization? By extending a cell-cycle model previously developed for embryos of the frog Xenopus laev...

Background This study was designed to develop a new co-culture system, assess the effect of luteinizing hormone (LH) using sequential media to promote development and increase the quality of 2-cell murine embryos through the 8-16 cell stage to morula and blastocyst stages. MaterialsAndMethods Monolayers for co-culture were prepared from ovine oviduct epithelial cells (OOEC) in DMEM/F12 medium a...

Objective A unique feature of embryo metabolism is production of reactive oxygen species (ROS). It is well established that during in vitro culture, ROS levels increase over normal ranges observed for embryos developed in vivo. This study evaluates and compares the stepwise pattern of ROS production during in vitro development of reconstructed goat embryos produced by zona-free method of somati...

Cells of mouse embryos develop a polarization of microvillous distribution at compaction. Cells of the 4-cell embryo show a uniform pattern of fluorescent-ligand binding and an even distribution of microvilli. Each cell of the early 8-cell embryo has a uniform distribution both of microvilli and of fluorescent ligand. During the 8-cell stage, there is a progressive increase in the incidence of ...

background: it has been demonstrated that performing a mock embryo transfer (et) significantly improves the pregnancy rate in ivf cycles. the mock et could be performed prior to the stimulation cycle or immediately before real et. the problem of the first procedure is the possibility of variation in the uterine position and or cervico�uterine angle. objective: the purpose of this study was to d...