Heat-induced and spontaneous expression of Hsp70.1Luciferase transgene copies localized on Xp22 in female bovine cells

<p>Abstract</p> <p>Background</p> <p>Expression of several copies of the heat-inducible <it>Hsp70.1Luciferase </it>(<it>LUC</it>) transgene inserted at a single X chromosome locus of a bull (<it>Bos taurus</it>) was assessed in females after X-chromosome inactivation (XCI). Furthermore, impact of the chromosomal environment on the spontaneous expression of these transgene copies before XCI was studied during early development in embryos obtained after in vitro fertilization (IVF), when the locus was carried by the X chromosome inherited from the bull, and after somatic cell nuclear transfer (SCNT) cloning, when the locus could be carried by the inactive Xi or the active Xa chromosome in a female donor cell, or by the (active) X in a male donor cell.</p> <p>Findings</p> <p>Transgene copies were mapped to bovine Xp22. In XX^{<it>LUC </it>}female fibroblasts, i.e. after random XCI, the proportions of late-replicating inactive and early-replicating active X^{<it>LUC </it>}chromosomes were not biased and the proportion of cells displaying an increase in the level of immunostained luciferase protein after heat-shock induction was similar to that in male fibroblasts. Spontaneous transgene expression occurred at the 8-16-cell stage both in transgenic (female) embryos obtained after IVF and in male and female embryos obtained after SCNT.</p> <p>Conclusions</p> <p>The X^{<it>LUC </it>}chromosome is normally inactivated but at least part of the inactivated X-linked <it>Hsp70.1Luciferase </it>transgene copies remains heat-inducible after random XCI in somatic cells. Before XCI, the profile of the transgenes' spontaneous expression is independent of the epigenetic origin of the X^{<it>LUC </it>}chromosome since it is similar in IVF female, SCNT male and SCNT female embryos.</p

IGF-I and IGF-II receptors in the sheep placenta : evolution during the course of pregnancy

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Influence d’une supplémentation en omégas 3 au cours de la grossesse

Maternal nutrition is a major environmental factor, which can be modified and can affect fetal growth and development with potential long-term consequences. There is currently a strong mediatic pressure for supplementing diets with omega 3 fatty acids. Nevertheless, if beneficial effects seem to be confirmed in adults and in animal models, the evidence for favourable effects of omega 3 supplementation in pregnant women are less obvious. Indeed, there is a trend showing a positive effect on cerebral development, but long term effects have not been demonstrated and both the quantity of omega 3 and the omega 3:omega 6 ratios are not precisely determined. Numerous studies are needed, both in pregnant animal models and in patients, to unravel these effects.L’alimentation est un facteur environnemental majeur, modifiable, pouvant avoir une action sur le développement et la croissance fœtale avec de possibles conséquences a très long terme. Il existe actuellement une forte pression médiatique en faveur de la supplémentation en oméga 3. Cependant, force est de constater que, si les preuves d’un bénéfice semblent exister chez l’adulte et chez l’animal, cela est loin d’être le cas chez la femme enceinte. Il existe cependant une tendance en faveur d’une action favorable sur le développement cérébral, sans que les effets à long terme soient démontrés. La quantité d’oméga 3, le rapport oméga 3/oméga 6 idéaux ne sont pas déterminés avec certitude. De nombreuses études sont donc encore à mettre en place, tant chez l’animal que chez la femme afin de répondre à ces questions

Expression of the growth hormone gene in ovine placenta : detection and cellular localization of the protein.

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Effect of a hyperlipidic hypercholesterolaedomic diet in pubertal does on fetal and post natal development

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Occurence of a growth hormone in the ovine placenta

Résumé A39International audienc

Expression of growth hormone and its receptor in the placental and feto-maternal environment during early pregnancy in sheep

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Coccygeal chordoma in a degu: case report and review of the literature

International audienceAn 8-y-old, intact female degu (Octodon degus) was presented with a slow-growing mass on the tail tip. The mass was completely removed by partial caudectomy. Histologically, the last coccygeal vertebra was replaced by a lobulated neoplasm composed of large clear polygonal cells embedded in a myxoid alcian blue-positive matrix with highly vacuolated cytoplasm (physaliferous cells) and intracytoplasmic periodic acid-Schiff-positive granules. The neoplasm exhibited the morphologic features of a "classic" chordoma of humans, which is 1 of 3 distinct chordoma subtypes. Immunohistochemistry revealed dual expression of cytokeratin AE1/AE3 and vimentin, consistent with a diagnosis of chordoma. Chordomas are uncommon slow-growing neoplasms in humans and animals, arising from notochordal remnants. Depending on their subtype and location, they can have a high local recurrence rate and metastatic risk. Chordoma should be included in the differential diagnosis of a soft tissue mass on the tail of a degu, similar to the clinical situation in ferrets