Publications by authors named "Otavio Mitio Ohashi"

In this longitudinal study, the anti-Müllerian hormone (AMH) levels in blood were determined in 32 Murrah buffalo females at 8, 10, 12, 16 and 19 months of age when females were synchronized and the antral follicular population (AFP) was estimated. Correlations of AFP to the AMH level at 19 months of age and retrospectively to younger ages were investigated. Then females were split into high and low AFP, and their AMH levels were compared for all ages and tested as predictors of AFP categories.

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Despite the cytotoxicity and embryotoxicity previously reported artesunate is a recommended drug to treat malaria for adults, children, and women in the first trimester of pregnancy. To address the putative effects of artesunate on female fertility and preimplantation embryo development, when the pregnancy is not detectable yet, artesunate was added to the oocyte maturation and embryo development of bovine. Briefly, in experiment 1 the cumulus-oocyte complexes (COCs) were matured for 18 h with 0.

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Ruminant energy supplementation with vegetable oils or fats has been standing out worldwide and oil palm processing has been receiving growing interest. This study assessed the effect of supplementation with saturated and unsaturated fatty acids from the palm oil industry on the lipid profile of seminal plasma and of the sperm membrane, as well as on the morphological and functional characteristics of raw and cryopreserved buffalo semen. Twelve purebred Murrah bulls () were assigned to the experimental groups and fed diets for 120 days with no added lipids (CONT, four bulls), or with an extra amount of 3% lipids from crude palm oil (PALM, four bulls), or from palm oil deodorizer distillate (PODD, four bulls).

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Heat stress reduces the reproductive capacity of bulls raised in tropical climate. However, the reestablishment of scrotal thermoregulation and the dynamics of sperm defects emergence after stress are not completely known in buffaloes. Thus, the study aimed to evaluate the effect of short-term heat stress over scrotal thermoregulation and sperm attributes, relating them to spermatogenesis stages.

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Sex selection through sperm sorting offers advantages in regards selection pressure in high-producing livestock. However, the sex-sorting process results in sperm membrane and DNA damage that ultimately decrease fertility. We hypothesized that given the role of protamines in DNA packaging, protamine deficiency could account, at least partially, for the DNA damage observed following sperm sex sorting.

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Transvaginal follicular aspiration technique together with embryo production are the biotechnological alternatives currently available to support genetic improvement breeding programs in buffalo species. However, aspects related to animal management, lack of knowledge of the metabolic needs and biochemical peculiarities of gametes and embryos, as well as the reproductive physiology characteristics have hampered progress in the results. Despite the low availability of good quality oocytes collected after OPU in donors as a physiological characteristic of buffalo species, high rates of oocyte maturation, modest embryo cleavage, blastocyst production and pregnancy rates after transvaginal embryo transfer in recipients could be obtained in buffalo embryo production programs.

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Embryo Production (IVP) is widely used to improve the reproductive efficiency of livestock animals, however increasing the embryo development rates and pregnancy outcomes is still a challenge for some species. Thus, the lack of biological knowledge hinders developing specie-specific IVP protocols. Therefore, the contributions of RNA-seq to generate relevant biological knowledge and improve the efficiency of IVP in livestock animals are reviewed herein.

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Consequences of oocyte supplementation with l-carnitine may vary depending on species-specific cellular lipid profile, level of mitochondrial activity, or even on ipid availability in culture medium. This study aimed to evaluate l-carnitine supplementation on competence and gene expression of enzymes related to lipid metabolism in oocytes and cumulus cells from buffalo COCs matured in the presence or absence of fetal bovine serum (FBS). COCs were matured in vitro in FBS (10%) or bovine serum albumin fatty acid-free (BSA-FAF) (0.

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The knowledge about the biological events that regulate lipid metabolism in oocytes and embryos in buffalo is scarce. Lipogenesis, lipolysis, transport and oxidation of fatty acids (FAs) occur in gametes and embryonic cells of all mammalian species, as an intrinsic component of energy metabolism. In oocytes and cumulus cells, degradation of lipids is responsible for the production of ATP that is essential for the metabolic processes that lead to oocyte maturation in in vivo and in vitro culture conditions.

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Purpose: To evaluate the effects of this thymol-rich oil in the proliferation of human adipose tissue-derived stem cells.

Methods: Stem cells were isolated from human adipose tissue by liposuction. After the first passage, cells were cultivated in triplicate for three days in control medium and medium supplemented with three oil samples (1.

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Somatic cell nuclear transfer (SCNT) success is partially hindered by the low epigenetic reprogramming efficiency of the donor cell. Previous studies suggest cellular heterogeneity among donor nuclei in regard to reprogramming potential, which precludes comparison among different strategies to increase cloning success. In this context, we evaluated the effect of using clonal cell populations (CPs) of bovine adult fibroblasts established by single-cell plating in SCNT.

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Purpose:: To evaluate the Adipose Stem Cells (ACS) therapy efficacy on the time and quality of wound healing process in rats.

Methods:: Nine male Wistar rats were randomly distributed into three groups I) 7 days of healing; II) 14 days of healing; III) 21 days of healing. Four incisions were made on the dorsal surface of each rat and then treated with intralesional ACS, meloxicam, and no treatment and ACS+meloxicam.

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The agouti (Dasyprocta sp.) is a hystricomorph rodent found in some regions of the Americas. It is an important cynegetic species, which indicates that the overhunting is a threat to their conservation.

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The goal of this study was to describe the sexual behavior in female and male collared peccary. Twenty females and twelve males were monitored in familiar and non-familiar units for two 60 days periods. During both phases, we recorded 2747 sexual interactions initiated by 20 different females toward males and 4461 sexual interactions initiated by 12 males toward females.

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Glucocorticoids (GCs) are important mediators of key cellular events. Herein, we investigated the effect of adding cortisol to the IVM medium on the acquisition of developmental competency in bovine oocytes. Cortisol (0.

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Article Synopsis
  • * Different concentrations of L-arginine (0, 1, 10, and 50 mM) were tested for their impact on fertilization rates, the production of nitric oxide, cleavage, blastocyst rates, and total blastocyst cell numbers over time.
  • * The results showed that while high concentrations (50 mM) of L-arginine harmed embryo development, a lower concentration (1 mM) with Bos indicus sperm improved the rate of hatched blastocysts, suggesting that too much L
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Nitric oxide (NO) is a cell-signaling molecule that regulates a variety of molecular pathways. We investigated the role of NO during preimplantation embryonic development by blocking its production with an inhibitor or supplementing in vitro bovine embryo cultures with its natural precursor, L-arginine, over different periods. Endpoints evaluated included blastocyst rates, development kinetics, and embryo quality.

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Ovum pick up (OPU) associated with in vitro production (IVP) of embryos has been shown as an important tool in cattle breeding to increase the number of descendants from animals of high genetic value. In herds maintained distant from the laboratory, collecting cumulus-oocyte complexes (COCs) and transporting them to the laboratory may take several hours and decrease COCs viability, representing a challenge for commercial settings. In this study, a prematuration culture to induce temporary meiosis block was evaluated in a commercial scale IVP setting as a strategy to transport bovine OPU-derived COCs from Nelore and Brangus donors.

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Because the collared peccary (Tayassu tajacu) has a peculiar Leydig cell cytoarchitecture, this species represents a unique mammalian model for investigating testis function. Taking advantage of the well-established and very useful testis xenograft technique, in the present study, testis tissue and testis cell suspensions from immature collared peccaries (n=4; 3 months old) were xenografted in SCID mice (n=48) and evaluated at 2, 4, 6, and 8 months after grafting. Complete spermatogenesis was observed at 6 and 8 months after testis tissue xenografting.

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In vitro-produced embryos store high lipid content in cytoplasmic lipid droplets (LD), and reduction or removal of LD has been demonstrated to improve freeze-thaw viability. The Perilipin Adipophilin Tail-interacting Protein of 47 kD (PAT) family of proteins is involved in the formation and regulation of LD in many cell types, but their presence has not been addressed either in cattle oocytes or preimplantation embryos. Therefore, this study aimed to detect the expression of PAT family transcripts (Perilipin-2 [PLIN2] and Perilipin-3 [PLIN3]) in immature and in vitro-matured (IVM) oocytes, and in in vitro-produced embryos at the stages of two to four cells, eight to 16 cells, morulae (MO), and blastocyst (BL).

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Background: Melatonin inclusion into in vitro oocyte maturation (IVM) protocols has been suggested because it possesses a powerful free radical scavenger capability that improves the quality of the oocyte used in in vitro embryo production (IVP). The aim of our study was to investigate the presence of melatonin membrane receptors (MT1and MT2) and MT3, which is the melatonin binding site of NQO2 enzyme, in both oocytes and hatched blastocysts to consider an additional subcellular mechanism responsible for the effects of melatonin on IVP.

Methods: The presence of the high affinity melatonin receptors was investigated through an autoradiographic binding assay, using the non-permeable ligand [125I]-iodomelatonin (17 pM) in embryos.

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Cell death by apoptosis is considered to be irreversible. However, reports have indicated that its reversibility is possible if the cells have not yet reached the "point of no return." In order to add new information about this topic, we used cells at different moments of apoptotic process as nuclear donors in somatic cell nuclear transfer (SCNT) in order to test if programmed cell death can be reversed.

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Plasma concentration of progesterone and 17beta-estradiol of black-rumped agouti (Dasyprocta prymnolopha) during the estrous cycle. The agouti is a game animal that have been raised in captivity for conservation and sustainability purposes. However, the management of wild animals in an intensive breeding system requires an assertive knowledge of its reproductive parameters, one of the most important features for production improvement.

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Cell cycle synchronization by serum starvation (SS) induces apoptosis in somatic cells. This side effect of SS is hypothesized to negatively affect the outcome of somatic cell nuclear transfer (SCNT). We determined whether apoptotic fibroblasts affect SCNT yields.

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