Enhanced RNAi does not provide efficient innate antiviral immunity in mice.

In RNA interference (RNAi), long double-stranded RNA is cleaved by the Dicer endonuclease into small interfering RNAs (siRNAs), which guide degradation of complementary RNAs. While RNAi mediates antiviral innate immunity in plants and many invertebrates, vertebrates have adopted a sequence-independent response and their Dicer produces siRNAs inefficiently because it is adapted to process small hairpin microRNA precursors in the gene-regulating microRNA pathway. Mammalian endogenous RNAi is thus a rudimentary pathway of unclear significance.

First Baby Born in Brazil after Simultaneous Diagnosis through Non-Invasive and Conventional PGT-A.

Non-invasive preimplantation genetic testing for aneuploidies (niPGT-A) aiming to assess cell-free embryonic DNA in spent culture media is promising, especially because it might overcome the diminished rates of implantation caused by the inadequate performance of trophectoderm (TE) biopsy. Our center is part of the largest study to date assessing the concordance between conventional PGT-A and niPGT-A, and we report here the delivery of the first baby born in Brazil using niPGT-A. The parents of the baby were admitted to our center in 2018.

Physiologically relevant miRNAs in mammalian oocytes are rare and highly abundant.

miRNAs, ~22nt small RNAs associated with Argonaute (AGO) proteins, are important negative regulators of gene expression in mammalian cells. However, mammalian maternal miRNAs show negligible repressive activity and the miRNA pathway is dispensable for oocytes and maternal-to-zygotic transition. The stoichiometric hypothesis proposed that this is caused by dilution of maternal miRNAs during oocyte growth.

Preimplantation genetic testing for aneuploidies does not increase success rates in fresh oocyte donation cycles: a paired cohort study.

Purpose: To determine whether in vitro fertilization cycles using fresh oocyte donations benefit from preimplantation genetic testing for aneuploidies.

Methods: A paired cohort study compared 44 fresh oocyte donation cycles with or without preimplantation genetic testing for aneuploidy (PGT-A). The sibling oocyte study analyzed fertilized oocytes, blastocyst development, and euploidy rate.

Morphology-based selection from available euploid blastocysts induces male-skewed sex proportion in the offspring.

Purpose: To determine whether blastocyst morphology has an impact on sex proportion at pre-implantation and birth in PGT-A and non-PGT-A cycles.

Methods: A total of 1254 biopsied blastocysts from 466 PGT-A cycles were analyzed for sex proportion, day of biopsy, degree of expansion, inner cell mass (ICM), and trophectoderm (TE) morphology. From these, 197 frozen single embryo transfers (SET) were assessed for clinical outcomes and sex proportion of ongoing pregnancies and deliveries.

Pronuclear and blastocyst morphology are associated age-dependently with embryo ploidy in fertilization cycles.

This retrospective study aimed to assess the relationship between standard markers of embryo morphology, maternal age and blastocyst ploidy determined by trophectoderm (TE) biopsy and Next-generation Sequencing (NGS). A total of 774 oocytes and embryos from 288 PGT-A cycles were scored for pronuclear, cleavage stage and blastocyst morphology. Pronuclear oocytes aligned between the nuclei and presenting equal number of nucleolus precursor bodies (NPBs) were designated Z1, oocytes showing equal number of NPBs, but not aligned, as Z2 while Z3 oocytes had an unequal number of NBPs between the nuclei or NPBs aligned in one nucleus and non-aligned in the other.

The Effects of Overweight and Obesity on Assisted Reproduction Technology Outcomes.

The aim of the present study was to assess the impact of professional nutrition assistance on assisted reproduction technology (ART) outcomes in overweight or obese patients with polycystic ovarian syndrome (PCOS). The study represents a retrospective analysis of fertilization rates, embryo quality and gestations after ART in seven PCOS patients, five obese and two overweight. The women attended a private Fertility Center in Brazil between the years 2010 and 2016.

Effects of zinc transporters on Cryptococcus gattii virulence.

Zinc is an essential nutrient for all living organisms because it is a co-factor of several important proteins. Furthermore, zinc may play an essential role in the infectiousness of microorganisms. Previously, we determined that functional zinc metabolism is associated with Cryptococcus gattii virulence.

Molecular detection and characterization of BK and JC polyomaviruses in urine samples of renal transplant patients in Southern Brazil.

The human polyomaviruses JC (JCPyV) and BK (BKPyV) are widespread in the human population. Following the primary infection, virus reactivation may lead to nephropathy and graft rejection in renal transplant patients. This study was carried out to access the presence of BKPyV and JCPyV DNA in urine samples collected from renal transplant patients (n = 92) and healthy individuals (n = 88) in Porto Alegre, Rio Grande do Sul.