Publications by authors named "Flavio Meirelles"

-produced blastocysts are exposed to different stimuli when compared with ones. This includes the culture of embryos in a sturdy petri-dish, while embryos develop in a soft and dynamic structure. Here we hypothesized that a softer environment could differently modulate the produced embryos To that aim, presumptive zygotes were produced by fertilization and divided into three groups: 1) Cultured in a regular Petri dish - Control (CON); 2) Cultured on top of an alginate hydrogel surface (TOP); 3) Encapsulated inside an alginate hydrogel sphere (ENC) and cultured.

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Developing embryos are susceptible to fluctuations in the nutrients and metabolites concentrations within the reproductive tract, which can lead to alterations in their developmental trajectory. Ketotic dairy cows have diminished fertility, and elevated levels of the ketone body beta-hydroxybutyrate (BHB) have been associated with poor embryonic development. We used an in vitro model based on either in vitro fertilization (IVF) or parthenogenesis to investigate the effects of BHB on the preimplantation bovine embryo development, epigenome, and transcriptome.

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The use of C-type natriuretic peptide (CNP) in the interaction with the oocyte and in the temporary postponement of spontaneous meiosis resumption has already been well described. However, its action in pre-implantation developmental-stage embryos is yet to be understood. Thus, our study aimed to detect the presence of the canonical CNP receptor (natriuretic peptide receptor, NPR2) in germinal vesicle (GV)-, metaphase II (MII)-, presumptive zygote (PZ)-, morula (MO)-, and blastocyst (BL)-stage embryos and, later, to observe possible modulations on the embryos when co-cultured with CNP.

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The first interactions among the embryo, endometrium, and corpus luteum (CL) are essential for pregnancy success. Small extracellular vesicles (sEVs) are part of these interactions. We previously demonstrated that sEVs from in vivo- or in vitro-produced bovine embryos contain different miRNA cargos.

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Biomaterials derived from biological matrices have been widely investigated due to their great therapeutic potential in regenerative medicine, since they are able to induce cell proliferation, tissue remodeling, and angiogenesis . In this context, highly vascularized and proliferative tissues, such as the uterine wall, present an interesting source to produce acellular matrices that can be used as bioactive materials to induce tissue regeneration. Therefore, this study aimed to establish an optimized protocol to generate decellularized uterine scaffolds (dUT), characterizing their structural, compositional, and biomechanical properties.

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This study explored the migration of follicular fluid (FF)-derived extracellular vesicles (EVs) of the uterine environment to the bloodstream and their interaction with neutrophils and . For the experiment, six Nellore heifers () received an intrauterine infusion seven days after ovulation with 1X PBS only (sham group; n=1), 1X PBS stained with lipophilic dye PKH26 (control group; n=2), or FF-derived EVs stained with PKH26 (treated group; n=3). Plasma was collected at 0, 10, 30, 60-, 180-, 360-, 720-, and 1440-min post-infusion to obtained EVs for analysis by nano flow cytometry.

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Maximal oxygen uptake (VOmax) is a determining indicator for cardiorespiratory capacity in endurance athletes, and epigenetics is crucial in its levels and variability. This initial study examined a broad plasma miRNA profile of twenty-three trained elite endurance athletes with similar training volumes but different VOmax in response to an acute maximal graded endurance test. Six were clustered as higher/lower levels based on their VOmax (75.

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Progesterone (P4) is predicted to act as a negative regulatory hormone for oocyte maturation events; however, its local effects during follicular development remain poorly understood in bovine. The complex process of oocyte meiosis progression is dependent on cellular communication among follicular cells. Besides, the breakdown of this communication, mainly between cumulus cells (CC) and oocyte, through the retraction of cumulus projections connecting these cells can impact oocyte maturation.

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Selection strategies are performed post-fertilization when the random combination of paternal and maternal genomes has already occurred. It would be greatly advantageous to eliminate meiotic uncertainty by selecting genetically superior gametes before fertilization. To achieve this goal, haploid embryonic cells and embryonic stem cell lineages could be derived, genotyped, and used to substitute gametes.

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Article Synopsis
  • The study investigates the role of the extracellular matrix (ECM) in uterine tube physiology and aims to create region-specific decellularized scaffolds from porcine uterine tubes for tissue engineering applications.
  • To achieve this, porcine uterine tubes were treated with specific solutions to remove cellular components while preserving the ECM structure and composition.
  • Experimental results showed successful decellularization, maintaining the scaffold’s structural integrity, and high cell viability, indicating potential use in reproductive biotechnology.
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During oocyte meiosis resumption, a coordinated program of transcript translation and decay machinery promotes a remodeling of mRNA stores, which determines the success of the acquisition of competence and early embryo development. We investigated levels of two genes related to mRNA translation ( and ) and two related to mRNA degradation ( and ) machinery and found downregulated in -matured bovine oocytes compared to counterparts. Thereafter, we tested the effects of a pre-IVM step with NPPC and a modified IVM with AREG on the modulation of members of mRNA translation and degradation pathways in cumulus cells and oocytes.

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While cryopreservation of cauda epididymal sperm (SpCau) allows the preservation of post-mortem bulls' gametes, the process triggers sperm damage. Although improving post-thaw sperm quality, using egg yolk extenders (EY) raises biosafety concerns which forces the use of EY-free extenders (EYFE). Since EYFE are less efficient in preserving post-thaw sperm quality, a strategy for ejaculated sperm (SpEj) frozen with EYFE is to add an Equilibrium Time (ET) step period to the cryopreservation process.

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This study aimed to evaluate the effect of including soybean molasses (SM) on performance, blood parameters, carcass traits, meat quality, fatty acid, and muscle (longissimus thoracis) transcriptomic profiles of castrated lambs. Twenty Dorper × Santa Inês lambs (20.06 ± 0.

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Background: It is well described that circulating progesterone (P4) plays a key role in several reproductive events such as oocyte maturation. However, during diestrus, when circulating P4 is at the highest concentrations, little is known about its local impact on the follicular cells such as intrafollicular P4 concentration due to corpus luteum (CL) presence within the same ovary. Based on that, our hypothesis is that the CL presence in the ovary during diestrus alters intrafollicular P4 concentrations, oocyte competence acquisition, follicular cells gene expression, and small extracellular vesicles (sEVs) miRNAs contents.

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Background: The worldwide growing demand for human insulin for treating diabetes could be supplied by transgenic animals producing insulin in their milk.

Methods And Results: Pseudo-lentivirus containing the bovine β-casein promoter and human insulin sequences was used to produce modified adult fibroblasts, and the cells were used for nuclear transfer. Transgenic embryos were transferred to recipient cows, and one pregnancy was produced.

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Histone deacetylation is an important mechanism involved in human breast cancer tumorigenesis and recent veterinary oncology studies also demonstrate a similar relationship in some canine neoplasms. The use of HDAC inhibitors and has demonstrated antitumor action on several strains of human and animal cancers. The present study aims to correlate the expression of H3K9Ac, H4K12Ac, HDAC1, HDAC2 and HDAC6 in simple mammary carcinomas in dogs with clinicopathological parameters and overall survival time.

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Haploid embryos have contributed significantly to our understanding of the role of parental genomes in development and can be applied to important biotechnology for human and animal species. However, development to the blastocyst stage is severely hindered in bovine haploid androgenetic embryos (hAE). To further our understanding of such developmental arrest, we performed a comprehensive comparison of the transcriptomic profile of morula-stage embryos, which were validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) of transcripts associated with differentiation in haploid and biparental embryos.

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Mechanisms of cell reprogramming by pluripotency-related transcription factors or nuclear transfer seem to be mediated by similar pathways, and the study of the contribution of OCT4 and SOX2 in both processes may help elucidate the mechanisms responsible for pluripotency. Bovine fibroblasts expressing exogenous or , or both, were analyzed regarding the expression of pluripotency factors and imprinted genes and , and used for in vitro reprogramming. The expression of the gene was increased in the control sorted group, and putative iPSC-like cells were obtained when cells were not submitted to cell sorting.

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The present study developed a review and exploration of data in public and already validated repositories. The main objective was to identify the pathways involved in ruminants' cervical dilatation, which are conserved between cattle and sheep in the follicular and luteal phases of the reproductive cycle. In cattle, 1961 genes were more differentially expressed in the follicular phase and 1560 in the luteal phase.

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Despite the advances in in vitro embryo production (IVP) over the years, the technique still has limitations that need to be overcome. In cell cultures, it is already well established that three-dimensional culture techniques are more physiological and similar to the in vivo development. Liquid marble (LM) is a three-dimensional system based on the use of a hydrophobic substance to create in vitro microbioreactors.

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Cloning by somatic cell Nuclear Transfer (SCNT) is a powerful technology capable of reprograming terminally differentiated cells to totipotency for generating whole animals or pluripotent stem cells for use in cell therapy, drug screening, and other biotechnological applications. However, the broad usage of SCNT remains limited due to its high cost and low efficiency in obtaining live and healthy offspring. In this chapter, we first briefly discuss the epigenetic constraints responsible for the low efficiency of SCNT and current attempts to overcome them.

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Aiming to evaluate the effects of increased body energy reserve (BER) in Nellore cows' reproductive efficiency, cows were fed with different nutritional plans to obtain animals with high BER (HBER; Ad libitum diet) and moderate BER (MBER: cows fed 70% of HBER group ingestion). To evaluate the BER, cows were weekly weighted and evaluated for subcutaneous fat thickness and insulin serum concentration along the experimental period. At the end of the experimental period, animals were submitted to estrous synchronization and artificial insemination.

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Much effort has been employed to improve the quality of embryos obtained by in vitro production (IVP) given the relevance of this technology to current livestock systems. In this context, dynamic IVP systems have proved beneficial to the embryo once they mimic fluid flows and mechanical forces resulting from the movement of ciliated cells and muscle contraction in the reproductive tract. In the present study, we sought to confirm these initial findings as well as assess potential molecular consequences to the embryo by applying micro-vibration (45 Hz for 5 s once per 60 min) during both oocyte maturation and embryo culture in cattle.

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Besides their canonical roles as energy sources, short-chain fatty acids act as metabolic regulators of gene expression through histone posttranslational modifications. Ketone body β-hydroxybutyrate (BHB) causes a novel epigenetic modification, histone lysine β-hydroxybutyrylation (Kbhb), which is associated with genes upregulated in starvation-responsive metabolic pathways. Dairy cows increase BHB in early lactation, and the effects of this increase on cellular epigenomes are unknown.

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Background: The generation of induced pluripotent stem cells (iPSC) has been a game-changer in translational and regenerative medicine; however, their large-scale applicability is still hampered by the scarcity of accessible, safe, and reproducible protocols. The porcine model is a large biomedical model that enables translational applications, including gene editing, long term and offspring analysis; therefore, suitable for both medicine and animal production.

Aim: To reprogramme into pluripotency, and herein urine-derived cells (UDCs) were isolated from porcine urine.

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