Efecto del resveratrol en el porcentaje y calidad de embriones in vitro generados por separación de blastómeras en bovinos

The oxidative state is an important factor that determines the development of bovine embryos. The objective in this study was to evaluate the effect of resveratrol on the quality of in vitro embryos generated by separation of blastomeres in cattle. Oocytes from the slaughterhouse were matured and fertilized in vitro by the conventional method. After 18 hours of fertilization, the zygotes were cultured for 3 days in synthetic oviductual fluid medium (SOF) for control and supplemented with 2 μM and 0.5 μM for the treatments. On day 3 they were stripped of their zona pellucida (ZP) to be cultivated at a rate of four blastomeres in well of the well (WOW) for 6 days in medium SOF supplemented with resveratrol. We evaluated percentage data of cleavage and embryonic division (8 to 10 blastomeres) after 3 days of culture, finding a significant difference p<0.05 with supplementation with 0.5 μM of resveratrol. At 6 days after blastomeres separation, percentage of embryos, number of total cells, live cells and dead cells were evaluated using Hoechst, FDA and PI staining respectively. There were no differences in the percentage of blastocysts between treatments; however, supplementation with 0.5 μM of resveratrol to the SOF medium had a greater amount of total cells and living cells (p<0.05). In conclusion, supplementation with resveratrol in the SOF medium does not increase the percentage of blastocysts but improves its quality using a concentration of 0.5 μM.El estado oxidativo es un factor importante que determina el desarrollo de embriones bovinos. El objetivo de este estudio fue evaluar el efecto del resveratrol en el porcentaje y calidad de embriones in vitro generados por separación de blastómeras en ganado bovino. Ovocitos provenientes de matadero fueron madurados y fecundados in vitro por el método convencional. Terminada las 18 horas de fecundación, los cigotos se cultivaron por 3 días en medio fluido oviductual sintético (SOF) para el control y suplementado con 2 µM y 0,5 µM para los tratamientos. Al día 3 se despojaron de su zona pelúcida (ZP) para ser cultivados a razón de cuatro blastómeras en well of thewell (WOW) por 6 días en medio SOF suplementado con resveratrol. Se evaluaron datos porcentuales de clivaje y división embrionaria (8 a 10 blastómeros) a los 3 días de cultivo superando la suplementación con 0.5µM de resveratrol (p<0,05). A los 6 días post separación de blastómeras se evaluó porcentaje de embriones, cantidad de células totales, células vivas y células muertas, utilizando la tinción Hoechst, FDA y PI respectivamente. No hubo diferencias en el porcentaje de blastocistos entre tratamientos; sin embargo, la suplementación con 0,5 µM de resveratrol al medio SOF tuvo mayor cantidad de células totales y células vivas (p<0,05). Finalmente la suplementación con resveratrol al medio SOF no aumenta el porcentaje de blastocistos pero sí mejora su calidad usando una concentración de 0,5 µM

Effects of enamel matrix derivative and transforming growth factor-β1 on human osteoblastic cells

<p>Abstract</p> <p>Background</p> <p>Extracellular matrix proteins are key factors that influence the regenerative capacity of tissues. The objective of the present study was to evaluate the effects of enamel matrix derivative (EMD), TGF-β1, and the combination of both factors (EMD+TGF-β1) on human osteoblastic cell cultures.</p> <p>Methods</p> <p>Cells were obtained from alveolar bone of three adult patients using enzymatic digestion. Effects of EMD, TGF-β1, or a combination of both were analyzed on cell proliferation, bone sialoprotein (BSP), osteopontin (OPN) and alkaline phosphatase (ALP) immunodetection, total protein synthesis, ALP activity and bone-like nodule formation.</p> <p>Results</p> <p>All treatments significantly increased cell proliferation compared to the control group at 24 h and 4 days. At day 7, EMD group showed higher cell proliferation compared to TGF-β1, EMD + TGF-β1 and the control group. OPN was detected in the majority of the cells for all groups, whereas fluorescence intensities for ALP labeling were greater in the control than in treated groups; BSP was not detected in all groups. All treatments decreased ALP levels at 7 and 14 days and bone-like nodule formation at 21 days compared to the control group.</p> <p>Conclusions</p> <p>The exposure of human osteoblastic cells to EMD, TGF-β1 and the combination of factors <it>in vitro </it>supports the development of a less differentiated phenotype, with enhanced proliferative activity and total cell number, and reduced ALP activity levels and matrix mineralization.</p

Vapd In Xylella Fastidiosa Is A Thermostable Protein With Ribonuclease Activity.

Xylella fastidiosa strain 9a5c is a gram-negative phytopathogen that is the causal agent of citrus variegated chlorosis (CVC), a disease that is responsible for economic losses in Brazilian agriculture. The most well-known mechanism of pathogenicity for this bacterial pathogen is xylem vessel occlusion, which results from bacterial movement and the formation of biofilms. The molecular mechanisms underlying the virulence caused by biofilm formation are unknown. Here, we provide evidence showing that virulence-associated protein D in X. fastidiosa (Xf-VapD) is a thermostable protein with ribonuclease activity. Moreover, protein expression analyses in two X. fastidiosa strains, including virulent (Xf9a5c) and nonpathogenic (XfJ1a12) strains, showed that Xf-VapD was expressed during all phases of development in both strains and that increased expression was observed in Xf9a5c during biofilm growth. This study is an important step toward characterizing and improving our understanding of the biological significance of Xf-VapD and its potential functions in the CVC pathosystem.10e014576

Dog skin parasite load, TLR-2, IL-10 and TNF-α expression and infectiousness

Visceral leishmaniosis is a zoonotic disease that is transmitted by Lutzomyia longipalpis sandflies. Dogs are the main peri-urban reservoir of the disease, and progression of canine leishmaniosis is dependent on the type of immune response elaborated against the parasite. Type 1 immunity is characterized by effective cellular response, with production of pro-inflammatory cytokines such as tumour necrosis factor alpha (TNF-α). In contrast, Type 2 immunity is predominantly humoral, associated with progression of the disease and mediated by anti-inflammatory cytokines such as interleukin 10 (IL-10). Although seemly important in the dynamics of leishmaniosis, other gene products such as toll-like receptor 2 (TRL-2) and inducible nitric oxide synthase (iNOS) exert unclear roles in the determination of the type of immune response. Given that the dog skin serves as a micro-environment for the multiplication of Leishmania spp., we investigated the parasite load and the expression of TLR-2, iNOS, IL-10 and TNF-α in the skin of 29 infected and 8 control dogs. We found that increased parasite load leads to upregulation of TLR-2, IL-10 and TNF-α, indicating that abundance of these transcripts is associated with infection. We also performed a xenodiagnosis to demonstrate that increased parasitism is a risk factor for infectiousness to sandflies

Sheets of vertically aligned BaTiO₃ nanotubes reduce cell proliferation but not viability of NIH-3T3 cells

All biomaterials initiate a tissue response when implanted in living tissues. Ultimately this reaction causes fibrous encapsulation and hence isolation of the material, leading to failure of the intended therapeutic effect of the implant. There has been extensive bioengineering research aimed at overcoming or delaying the onset of encapsulation. Nanotechnology has the potential to address this problem by virtue of the ability of some nanomaterials to modulate interactions with cells, thereby inducing specific biological responses to implanted foreign materials. To this effect in the present study, we have characterised the growth of fibroblasts on nano-structured sheets constituted by BaTiO3, a material extensively used in biomedical applications. We found that sheets of vertically aligned BaTiO3 nanotubes inhibit cell cycle progression - without impairing cell viability - of NIH-3T3 fibroblast cells. We postulate that the 3D organization of the material surface acts by increasing the availability of adhesion sites, promoting cell attachment and inhibition of cell proliferation. This finding could be of relevance for biomedical applications designed to prevent or minimize fibrous encasement by uncontrolled proliferation of fibroblastic cells with loss of material-tissue interface underpinning long-term function of implants