PGDIS position statement on the transfer of mosaic embryos 2021.

Chromosome testing strategies, such as preimplantation genetic testing for aneuploidy (PGT-A), improve initial IVF outcomes by avoiding unwitting transfer of aneuploid embryos in morphology-based selection practices. Newer technologies have revealed that some embryos may appear to have intermediate whole chromosome (or parts of a chromosome termed segmental) copy number results suggesting trophectoderm mosaicism. An embryo with a trophectoderm mosaic-range result may be the only option for transfer for some patients. Recent data suggest that such mosaic embryos can be transferred without added risk of abnormal birth outcomes but may be associated with increased implantation failure and miscarriage rates, with higher values of mosaicism appearing to be less favourable for producing good outcomes. In this Position Statement, we provide guidance to laboratories, clinics, clinicians and counsellors to assist in discussions on the utility and transfer of mosaic embryos.

Apoptosis-related protein expression during pre- and post-natal testicular development after administration of glucocorticoid in utero in the sheep.

Pre-natal glucocorticoids are used in women at risk of preterm delivery to induce foetal lung maturation. However, glucocorticoids can produce negative outcomes for other tissues such as the reproductive system. We therefore tested the effects of pre-natal betamethasone on testicular morphology and apoptotic protein immune expression during pre- and post-natal development. Pregnant ewes (n = 42) bearing singleton male foetuses were randomly allocated to receive intramuscular injections of saline or betamethasone (0. 5 mg/kg) at 104, 111 and 118 days of gestation (DG). Testes were collected at 121 and 132 DG, and at 45 and 90 post-natal days (PD) and subjected to morphometric analysis (volume densities of sex cords and interstitial tissues; sex cord diameter). Immunohistochemistry (% stained area) was used to assess active caspase-3, Bax, Bcl-2 and cell-cycle proteins (PCNA). Compared with control values, betamethasone treatment decreased sex cord diameter at 121 DG, 45 and 90 PD, and sex cord volume at 90 PD. Active caspase-3 was decreased by betamethasone at 121 DG and 90 PD, but Bax was increased in all betamethasone groups. Bcl-2 and PCNA decreased in the betamethasone groups at 121 DG and 45 PD, but increased at 132 DG and 90 PD. We conclude that high levels of pre-natally administered glucocorticoid reduce foetal testicular development, perhaps via changes in the balance between pro- and anti-apoptotic proteins and cell-cycle proteins. These outcomes could compromise the future spermatogenic potential of male offspring.

Species Diversity and Temporal Variation of the Orchid-Bee Fauna (Hymenoptera, Apidae) in a Conservation Gradient of a Rocky Field Area in the Espinhaço Range, State of Minas Gerais, Southeastern Brazil.

This study investigated the orchid-bee community in a conservation gradient of the high-altitude rocky fields in the state of Minas Gerais, Brazil. Sampling was performed at two sites with different anthropic influences: a disturbed area (DA), with exotic plant species, and a preserved area (PA). From September 2009 through February 2011, males of euglossine bees were sampled using aromatic bait-traps. We collected a total of 819 specimens belonging to 11 species and three genera: Euglossa Latreille, Eulaema Lepeletier, and Eufriesea Cockerell. Despite the proximity of DA and PA (about 1.2 km), differences in orchid-bee abundance and richness were observed. Higher abundance was observed in the PA (n = 485) compared with the DA (n = 334). Eight species were common to both sites, and only the DA showed exclusive species. The DA showed higher diversity and higher estimated species richness. Euglossa leucotricha Rebêlo & Moure was the most abundant species at both sites followed by Euglossa melanotricha Moure. Higher abundance and richness were found in the warm rainy season. This study contributes to the knowledge of the orchid-bee fauna in the rocky fields and suggests that the greater resource availability in the DA was responsible for the higher orchid-bee diversity.