The inclusion of blastomeres into the inner cell mass in early-stage human embryos depends on the sequence of cell cleavages during the fourth division

The fate of the ICM in humans is still unknown, due to the ethical difficulties surrounding experimentation in this field. In this study we have explored the existing time-lapse recording data of embryos in the early stages of development, taking advantage of the large refractile bodies (RBs) within blastomeres as cellular markers. Our study found that the cellular composition of the ICM in humans is largely determined at the time of the fourth division and blastomeres which cleave first to fourth, during the fourth division from 8 cells to 16 cells, have the potential to be incorporated in the ICM

Dibutyryl Cyclic AMP Modulates Keratinocyte Migration Without Alteration on Integrin Expression

Cyclic adenosine monophosphate (cAMP) has long been regarded as a second messenger and a regulator of human keratinocyte proliferation. It has been demonstrated that cAMP inhibits keratinocyte proliferation when used at high concentrations. Nevertheless, new recent reports have demonstrated that cAMP may stimulate or inhibit keratinocyte growth depending upon the concentration used. Studies to examine the influence of cAMP upon the migration of other cell types have been contradictory. To determine the direct effect of dibutyryl cAMP (DBcAMP) upon human keratinocyte migration, we used a quantitative locomotion assay using a wide range of DBcAMP concentrations. We found a bi-phasic effect of DBcAMP on keratinocyte migration across connective tissue matrices. Keratinocyte locomotion on the matrices was promoted at 10-5 M and 10-6 M of DBcAMP, but not at higher or lower concentrations. Timecourse experiments demonstrated that the effect of DBcAMP on keratinocyte locomotion and proliferation occurred independently. Fluorescence-activated cell sorter analysis demonstrated that the effect of DBcAMP on the migration of human keratinocytes was independent from the modulation of integrin receptors. Although the cellular mechanisms by which DBcAMP promotes keratinocyte migration is unclear, the addition of DBcAMP or TPA to keratinocyte cultures enhanced the synthesis of a 92-kDa metalloproteinase in association with enhanced cellular migration. These observations suggest a possible link between metalloproteinase expression and cellular migration

Therapeutic Efficacy of Recombinant Canine Interferon-γ in Atopic Dogs

Sakurai Toru, Iwasaki Toshiroh, Hasegawa Atsuhiko. Therapeutic Efficacy of Recombinant Canine Interferon-γ in Atopic Dogs. In: Bulletin de l'Académie Vétérinaire de France tome 159 n°5, 2006. Séances thématiques exceptionnelles : Les maladies infectieuses. p. 404