10 research outputs found

    Efeitos do tratamento com inibidor da rock durante o estágio de pós-aquecimento de oócitos bovinos vitrificados sobre desenvolvimento embrionário / Effects of treatment with rock inhibitor during the post-warming stage of vitrified bovine oocytes on embryo development

    Get PDF
    Diversas biotécnicas vem sendo utilizadas para a preservação de material genético e manutenção a medio e longo prazo de gametas e embrioes de elevado valor genético, contribuindo para o avanço das estratégias para produção pecuária. O processo de vitrificação de oocitos bovinos é uma delas, entretanto com aplicação ainda restrita, pois durante o processo  podem ocorrer varias crio injurias. Afim de reduzir os danos causados pelo congelamento de oócitos e melhorar as taxas de  clivagem e desenvolvimento embrionário obtidas no cultivo in vitro, utilizou-se a exposição a Y-27632, um inibidor seletivo de quinases de proteínas específicas associadas com Rho durante o estágio de pós-aquecimento.  Nosso estudo demonstrou que a utilização de Y-27632 em oocitos bovinos maturados e submetidos a vitrificação promoveu  taxas mais elevadas de sobrevivência bem como maior número de embriões atingindo o etágio de blastocisto.

    Clonagem, sequenciamento e caracterização de genes normalizadores de Austrolebias charrua

    No full text
    O objetivo deste trabalho é apresentar a clonagem, o sequenciamento e a caracterização dos genes ef1α e h3f3a deste peixe

    Emerging technologies to create inducible and genetically defined porcine cancer models

    Get PDF
    There is an emerging need for new animal models that address unmet translational cancer research requirements. Transgenic porcine models provide an exceptional opportunity due to their genetic, anatomic and physiological similarities with humans. Due to recent advances in the sequencing of domestic animal genomes and the development of new organism cloning technologies, it is now very feasible to utilize pigs as a malleable species, with similar anatomic and physiological features with humans, in which to develop cancer models. In this review, we discuss genetic modification technologies successfully used to produce porcine biomedical models, in particular the Cre-loxP System as well as major advances and perspectives the CRISPR/Cas9 System. Recent advancements in porcine tumor modeling and genome editing will bring porcine models to the forefront of translational cancer research

    Effects of Two Types of Melatonin-Loaded Nanocapsules with Distinct Supramolecular Structures: Polymeric (NC) and Lipid-Core Nanocapsules (LNC) on Bovine Embryo Culture Model

    Get PDF
    <div><p>Melatonin has been used as a supplement in culture medium to improve the efficiency of <i>in vitro</i> produced mammalian embryos. Through its ability to scavenge toxic oxygen derivatives and regulate cellular mRNA levels for antioxidant enzymes, this molecule has been shown to play a protective role against damage by free radicals, to which <i>in vitro</i> cultured embryos are exposed during early development. <i>In vivo</i> and <i>in vitro</i> studies have been performed showing that the use of nanocapsules as active substances carriers increases stability, bioavailability and biodistribution of drugs, such as melatonin, to the cells and tissues, improving their antioxidant properties. These properties can be modulated through the manipulation of formula composition, especially in relation to the supramolecular structures of the nanocapsule core and the surface area that greatly influences drug release mechanisms in biological environments. This study aimed to evaluate the effects of two types of melatonin-loaded nanocapsules with distinct supramolecular structures, polymeric (NC) and lipid-core (LNC) nanocapsules, on <i>in vitro</i> cultured bovine embryos. Embryonic development, apoptosis, reactive oxygen species (ROS) production, and mRNA levels of genes involved in cell apoptosis, ROS and cell pluripotency were evaluated after supplementation of culture medium with non-encapsulated melatonin (Mel), melatonin-loaded polymeric nanocapsules (Mel-NC) and melatonin-loaded lipid-core nanocapsules (Mel-LNC) at 10<sup>−6</sup>, 10<sup>−9</sup>, and 10<sup>−12</sup> M drug concentrations. The highest hatching rate was observed in embryos treated with 10<sup>−9</sup> M Mel-LNC. When compared to Mel and Mel-NC treatments at the same concentration (10<sup>−9</sup> M), Mel-LNC increased embryo cell number, decreased cell apoptosis and ROS levels, down-regulated mRNA levels of <i>BAX</i>, <i>CASP3</i>, and <i>SHC1</i> genes, and up-regulated mRNA levels of <i>CAT</i> and <i>SOD2</i> genes. These findings indicate that nanoencapsulation with LNC increases the protective effects of melatonin against oxidative stress and cell apoptosis during <i>in vitro</i> embryo culture in bovine species.</p></div

    Hatching rates of bovine embryos cultured in the presence of free or nanoencapsulated melatonin.

    No full text
    <p>Mel = Non-encapsulated melatonin, Mel-NC = melatonin-loaded polymeric nanocapsules, Mel-LNC = melatonin-loaded lipid-core nanocapsules, NC = drug-unloaded nanocapsules, LNC = drug-unloaded lipid-core nanocapsules. Melatonin was used at 10<sup>−12</sup> M, 10<sup>−9</sup> M or 10<sup>−6</sup> M concentrations. Control group was cultured in SOFaa BSA alone. The numerators represent the numbers of hatched blastocysts and the denominators represent total blastocysts in each group. Different letters (a-c) above the bars indicate significant differences between groups (<i>P</i> < 0.05).</p

    ROS levels in 4–8 cell stage embryos cultured in the presence of free and nanoencapsulated melatonin.

    No full text
    <p>Embryos were cultured in the presence of 10<sup>−9</sup> M melatonin non-encapsulated (Mel) or encapsulated in nanocapsules (Mel-NC) or lipid-core nanocapsules (Mel-LNC). In the control group embryos were cultured in SOFaa BSA medium alone. Data represent mean ± S.E.M. Different letters above the error bars indicate significant differences between groups (P< 0.05). Representative fluorescent (B, C, D, E) and corresponding bright field (b, c, d, e) images of control, Mel, Mel-NC, and Mel-LNC embryos, respectively. Scale bar = 50 μm. Magnification = 100X.</p
    corecore