Publications by authors named "Marcia Marques Silveira"

Background: Several guidelines recommend the use of different classifiers to determine the risk of recurrence (ROR) and treatment decisions in patients with HR+HER2- breast cancer. However, data are still lacking for their usefulness in Latin American (LA) patients. Our aim was to evaluate the comparative prognostic and predictive performance of different ROR classifiers in a real-world LA cohort.

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The establishment of epigenetic marks during the reprogramming window is susceptible to environmental influences, and stimuli during this critical stage can cause altered DNA methylation in offspring. In a previous study, we found that low levels of sulphur and cobalt (low S/Co) in the diet offered to oocyte donors altered the DNA methylome of bovine embryos. However, due to the extensive epigenetic reprogramming that occurs during embryogenesis, we hypothesized that the different methylation regions (DMRs) identified in the blastocysts may not maintain in adulthood.

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The use of biological templates for the suitable growth of adipose-derived mesenchymal stem cells (AD-MSC) and "neo-tissue" construction has exponentially increased over the last years. The bioengineered scaffolds still have a prominent and biocompatible framework playing a role in tissue regeneration. In order to supply AD-MSCs, biomaterials, as the stem cell niche, are more often supplemented by or stimulate molecular signals that allow differentiation events into several strains, besides their secretion of cytokines and effects of immunomodulation.

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Introduction: The expression of retroviral envelope proteins in the placenta facilitates generation of the multinuclear syncytiotrophoblast as an outer cellular layer of the placenta by fusion of the trophoblastic cells. This process is essential for placenta development in eutherians and for successful pregnancy.

Methods: We tested the hypothesis that alterations in DNA methylation and gene expression profiles of the endogenous retroviruses (ERVs) and genes related to epigenetic reprogramming in placenta of cloned calves result in abnormal offspring phenotypes.

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XIST, in association with the shorter ncRNA RepA, are essential for the initiation of X chromosome inactivation (XCI) in mice. The molecular mechanisms controlling XIST and RepA expression are well characterized in that specie. However, little is known in livestock.

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Introduction: Cloning via somatic cell nuclear transfer (SCNT) has been associated with a variety of pathologies, primarily in the placenta, and these alterations may be associated with aberrant epigenetic reprogramming of the donor cell genome. We tested the hypothesis that DNA methylation patterns are not appropriately established after nuclear transfer and that those altered patterns are associated with specific aberrant phenotypes.

Methods: We compared global and specific placental DNA methylation patterns between aberrant and healthy SCNT-produced calves.

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