OBJECTIVES In the past several scoring systems were proposed for early human development aiming to assist in the identification of the best embryos. Scoring criteria are usually assessed at static developmental time points by microscopy. For almost every scoring system controversial results on its benefit can be found in the literature. With the introduction of time-lapse imaging static assessm...

Using RT-PCR and in situ hybridisation, we have analysed the temporal and spatial expression patterns of Xenopus Fox genes of subclass N. By screening cDNA libraries and by RT-PCR using embryonic RNA and primers derived from EST analyses, we could isolate FoxN2, FoxN4, FoxN5 and different isoforms of FoxN3. FoxN2 and FoxN3 transcripts were found during all developmental stages including early c...

A major and early feature of cartilage degeneration is proteoglycan breakdown. Matrix metalloprotease (MMP)-13 plays an important role in cartilage degradation in osteoarthritis (OA). This MMP, in addition to initiating collagen fibre cleavage, acts on several proteoglycans. One of the proteoglycan families, termed small leucine-rich proteoglycans (SLRPs), was found to be involved in collagen f...

Synthesis of mitotic spindle proteins is probably one of the normal preparations for division in higher cells (Mazia, 1961). Not so clear, however, is the situation in early embryonic development. The most widely accepted point of view, based upon several independent lines of evidence, is that the unfertilized egg contains a store of preformed spindle precursors, and that the controlling proces...

Using the whole-cell voltage clamp technique, we have studied junctional conductance (Gj), and Lucifer Yellow (LY) coupling in 2-cell and 32-cell ascidian embryos. Gj ranges from 17.5 to 35.3 nS in the 2-cell embryo where there is no passage of LY, and from 3.5 to 12.2 nS in the later embryo where LY dye spread is extensive. In both cases, Gj is independent of the transjunctional potential (Vj)...

extant limpet. In addition, bivalves also acquired a novel structure, adducter muscle to close the separated shell plate. Because the two novel structures, the separated shell plate and the adducter muscle appear early embryonic stage, their evolution should be understood as a modification of early development. To understand the evolution of bivalve bodyplan, we have traced the cleavage pattern...

extant limpet. In addition, bivalves also acquired a novel structure, adducter muscle to close the separated shell plate. Because the two novel structures, the separated shell plate and the adducter muscle appear early embryonic stage, their evolution should be understood as a modification of early development. To understand the evolution of bivalve bodyplan, we have traced the cleavage pattern...

extant limpet. In addition, bivalves also acquired a novel structure, adducter muscle to close the separated shell plate. Because the two novel structures, the separated shell plate and the adducter muscle appear early embryonic stage, their evolution should be understood as a modification of early development. To understand the evolution of bivalve bodyplan, we have traced the cleavage pattern...

Background: The aim of our study was to compare the resulting from transfer of embryos that cryopereserved in cleavage stage after thawing and transfer of embryos after thawing and culture in sequentional media until blastocyst formation. Materials and Methods: In this prospective clinical study, we have evaluated 128 cycles in women undergone in vitro fertilization (IVF) or intracytoplasmic sp...

The par-3 gene is required for establishing polarity in early C. elegans embryos. Embryos from par-3 homozygous mothers show defects in segregation of cytoplasmic determinants and in positioning of the early cleavage spindles. We report here that the PAR-3 protein is asymmetrically distributed at the periphery of the zygote and asymmetrically dividing blastomeres of the germline lineage. The PA...