Evaluation of targeted oxidative stress induced by oxygen-ozone in vitro after ischemic induction.

Encephalic vascular accident, or stroke, is the most common pathology of the central nervous system in humans, the second leading cause of death and physical and cognitive disabilities, in developing countries. It presents as an ischemic (more common) or hemorrhagic form. Ozone therapy has been shown to be effective in neuromodulation, neuroprotection, and nerve regeneration. The present study aimed to evaluate the effect of targeted mild ozone after inducing cerebral ischemia in vitro. Neuroblastoma lineage cells (SH-SY5Y) and canine amniotic membrane stem cells were subjected to 24 hours of hypoxia in an incubator culture chamber. The cells were evaluated by MTT assay, colorimetric assay spectrophotometry, fluorescence microscopy, and flow cytometry. Treatment with low concentrations of ozone (2-10 µg/mL), indicated a possible neuroregenerative effect at low concentrations, correlated with lower levels of apoptosis and oxidative stress compared to cells not subjected to hypoxia. High concentrations of ozone (18-30 µg/mL) promoted an increase in rate of apoptosis and cell death. We developed a novel protocol that mimics ozone therapy for ischemic stroke, using ozonized culture medium after hypoxia induction. Although more studies are needed, we conclude that ozone has a dose-dependent hormetic effect and can reverse the effect of ischemia in vitro at low concentrations.

Acquisition and maintenance of pluripotency are influenced by fibroblast growth factor, leukemia inhibitory factor, and 2i in bovine-induced pluripotent stem cells.

Several opportunities for embryo development, stem cell maintenance, cell fate, and differentiation have emerged using induced pluripotent stem cells (iPSCs). However, the difficulty in comparing bovine iPSCs (biPSCs) with embryonic stem cells (ESCs) was a challenge for many years. Here, we reprogrammed fetal fibroblasts by transient expression of the four transcription factors (Oct4, Sox2, Klf4, and c-Myc, collectively termed "OSKM" factors) and cultured in iPSC medium, supplemented with bFGF, bFGF2i, leukemia inhibitory factor (LIF), or LIF2i, and then compared these biPSC lines with bESC to evaluate the pluripotent state. biPSC lines were generated in all experimental groups. Particularly, reprogrammed cells treated with bFGF were more efficient in promoting the acquisition of pluripotency. However, LIF2i treatment did not promote continuous self-renewal. biPSCs (line 2) labeled with GFP were injected into early embryos (day 4.5) to assess the potential to contribute to chimeric blastocysts. The biPSC lines show a pluripotency state and are differentiated into three embryonic layers. Moreover, biPSCs and bESCs labeled with GFP were able to contribute to chimeric blastocysts. Additionally, biPSCs have shown promising potential for contributing to chimeric blastocysts and for future studies.

Influence of Elective Cesarean Calving (with and without Dexamethasone Induction) on the Erythrogram and Iron Serum Profiles in Nellore Calves.

The aim of the present study is to evaluate the erythrogram and iron serum profiles of neonatal calves born spontaneously or born by elective cesarean section with or without dexamethasone induction. The research was performed on 38 newborn Nellore calves. Three groups of calves were assigned according to the type of birth: calves born by spontaneous vaginal calving (n = 10), calves born by elective cesarean section without inducing labor (n = 14), and calves born by elective cesarean section with labor induction with dexamethasone (n = 14). Blood samples to assess red blood cell count (RBC), hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), concentration of mean corpuscular hemoglobin (MCHC), serum iron (SFe), total capacity to bind iron to transferrin (TIBIC), and transferrin saturation index (TSI) were performed at calving (0, 3, 6, and 12 h of life) and on 1, 2, 3, 5, 7, 10, 15, and 30 days of life. Regardless of the experimental group (calves born spontaneously, or born by elective cesarean section with or without dexamethasone induction), in the first day of life there was a decrease in the number of red blood cells, hemoglobin rates, and values of the globular volume. In the period of the first 10 days of life, animals from spontaneous vaginal delivery quickly recovered values of erythrocytes, hemoglobin, and packed cell volume, whereas animals born by elective C-section (induced and uninduced) did not recover as quickly in their rates of hemoglobin and packed cell volume values. In calves born by elective C-section (induced and uninduced), it was observed in their period between 10 and 30 days of life that the MCV and MCH were reduced by passing the presenting microcytic hypochromic when compared with calves obtained by spontaneous vaginal delivery. In the period between 10 and 30 days of life, the levels of SFe and TSI in animals born by elective C-section (induced and uninduced) are significantly lower. The differences in the erythrogram values between Nellore calves born spontaneously and those by elective C-section with or without induction must be considered consequent to the process of neonatal adaptation to extrauterine life. Iron supplementation in the first month of life in calves from cesarean could be recommended to prevent anemia of this iron deficiency.

Delivery of cloned offspring: experience in Zebu cattle (Bos indicus).

The production of a healthy cloned calf is dependent on a multitude of successful steps, including reprogramming mediated by the oocyte, the development of a functional placenta, adequate maternal-fetal interaction, the establishment of a physiological metabolic setting and the formation of a complete set of well-differentiated cells that will eventually result in well-characterised and fully competent tissues and organs. Although the efficiency of nuclear transfer has improved significantly since the first report of a somatic cell nuclear transfer-derived animal, there are many descriptions of anomalies concerning cloned calves leading to high perinatal morbidity and mortality. The present article discusses some our experience regarding perinatal and neonatal procedures for cloned Zebu cattle (B. indicus) that has led to improved survival rates in Nellore cloned calves following the application of such 'labour-intensive technology'.