1,125 research outputs found

    Cryopreservation of Sheep Produced Embryos – Current and Future Perspectives

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    Due to economical and scientific limitations, sheep embryo reproductive technologies are less commercially applied than in other animal species. However, it is very clear that, in the near future, those techniques are expected to have a central role in animal production as a consequence of genetic and reproductive demands. One drawback is that results obtained after sheep embryo cryopreservation are unattractive for commercial purposes. It is expected that a successful cryopreservation of sheep embryos can push forward all other reproductive biotechnologies in this species, such as multiple ovulation and embryo transfer (MOET), artificial insemination, or in vitro production of embryos. This paper tries to discuss the current and future perspectives of cryopreservation of in vivo- and in vitro-produced sheep embryos concerning advantages and limitations for its practical use and possible solutions for improving methods to allow a higher survival rate of cryopreserved embryos

    Using biotechnology to solve engineering problems Non-destructive testing of microfabrication components

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    Fundacao para a Ciencia e a Tecnologia, I.P. (FCT), Portugal, for financial support under program "Investigador FCT 2013" (IF/01203/2013/CP1163/CT0002) and UID/BIO/04565/2013. TS and RM acknowledge FCT for PEst-OE/EME/UI0667/2014 and UID/EMS/00667/2013. The study was also partially supported by project PTDC/EME-TME/118678/2010.In an increasingly miniaturised technological world, non-destructive testing (NDT) methodologies able to detect defects at the micro scale are necessary to prevent failures. Although several existing methods allow the detection of defects at that scale, their application may be hindered by the small size of the samples to examine. In this study, the application of bacterial cells to help the detection of fissures, cracks, and voids on the surface of metals is proposed. The application of magnetic and electric fields after deposition of the cells ensured the distribution of the cells over the entire surfaces and helped the penetration of the cells inside the defects. The use of fluorophores to stain the cells allowed their visualisation and the identification of the defects. Furthermore, the size and zeta potential of the cells and their production of siderophores and biosurfactants could be influenced to detect smaller defects. Micro and nano surface defects made in aluminium, steel, and copper alloys could be readily identified by two Staphylococcus strains and Rhodococcus erythropolis cells.publishersversionpublishe

    Effect of acetaldehyde intoxication and withdrawal on NPY expression: focus on endocannabinoidergic system involvement

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    Acetaldehyde (ACD), the first alcohol metabolite, plays a pivotal role in the rewarding, motivational, and addictive properties of the parental compound. Many studies have investigated the role of ACD in mediating neurochemical and behavioral effects induced by alcohol administration, but very little is known about the modulation of neuropeptide systems following ACD intoxication and withdrawal. Indeed, the neuropeptideY (NPY) system is altered during alcohol withdrawal in key regions for cerebrocortical excitability and neuroplasticity.The primary goal of this research was to investigate the effects of ACD intoxication and withdrawal by recording rat behavior and by measuring NPY immunoreactivity in hippocampus and NAcc, two brain regions mainly involved in processes which encompass neuroplasticity in alcohol dependence. Furthermore, on the basis of the involvement of endocannabinoidergic system in alcohol and ACD reinforcing effects, the role of the selective CB1 receptor antagonist AM281 in modulating NPY expression during withdrawal was assessed. Our results indicate that (i) ACD intoxication induced a reduction in NPY expression in hippocampus and NAcc; (ii) symptoms of physical dependence, similar to alcohol’s,were scored at 12 h from the last administration of ACD; and (iii) NPY levels increased in early and prolonged acute withdrawal in both brain regions examined. The administration of AM281 was able to blunt signs of ACD-induced physical dependence, to modulate NPY levels, and to further increase NPY expression during ACD withdrawal both in hippocampus and NAcc. In conclusion, the present study shows that complex plastic changes take place in NPY system during ACD intoxication and subsequent withdrawal in rat hippocampal formation and NAcc. The pharmacological inhibition of CB1 signaling could counteract the neurochemical imbalance associated with ACD, and alcohol withdrawal, likely boosting the setting up of homeostatic functional recover

    A new generation photodetector for astroparticle physics: the VSiPMT

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    The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design we proposed for a revolutionary photon detector. The main idea is to replace the classical dynode chain of a PMT with a SiPM (G-APD), the latter acting as an electron detector and amplifier. The aim is to match the large sensitive area of a photocathode with the performance of the SiPM technology. The VSiPMT has many attractive features. In particular, a low power consumption and an excellent photon counting capability. To prove the feasibility of the idea we first tested the performance of a special non-windowed SiPM by Hamamatsu (MPPC) as electron detector and current amplifier. Thanks to this result Hamamatsu realized two VSiPMT industrial prototypes. In this work, we present the results of a full characterization of the VSiPMT prototype

    IL-1β maintains the DNA hypermethylation of anti-inflammatory IL-10 gene in a human intestinal epithelial cell line

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    Intestinal inflammation is a natural process crucial to maintain gut integrity, but its deregulation is involved in the pathogenesis of severe intestinal disorders[1]. Intestinal epithelial cells play a crucial role in the inflammatory response, modulating the immune cell exposure to antigens and by their ability to secrete many inflammatory mediators. IL-1β represents a pivotal player: secreted by infiltrated leucocytes, it induces the expression of several pro-inflammatory genes. Also the anti-inflammatory IL-10, whose function is to terminate the inflammatory process, modulates the intestinal physiology[2]. Recent clinical reports showed that patients with ulcerative colitis in remission phase have significantly higher IL10 gene expression in mucosa compared with active patients and controls[3]. Moreover, in the latest years aberrant epigenetic mechanisms were put in binomial relationship with chronic inflammatory diseases[4]. Previously, we described a demethylation of pro-inflammatory IL6 and IL8 genes in human colonic Caco-2 cells differentiated into an enterocyte-like phenotype and exposed to the inflammatory action of IL-1β[5]. In the present study we evaluate whether the IL-1β treatment affected the methylation status of the anti-inflammatory IL10 gene, in the same in vitro model. Our results showed that IL-1β treatment did not change the hypermethylation status of the IL10 promoter. Moreover, in cell lysates from IL-1β-treated Caco-2 cells, we observed a dose-dependent increase of DNMTs activity and, surprisingly, a decrease of DNMT3b expression. These findings put in evidence the complexity of relationship between IL-1β and DNMTs, and may suggest a potential role of IL-1β as pleiotropic modulator of DNA methylation in Caco-2 cell line

    RELAÇÕES ENTRE ESTADO E SOCIEDADE CIVIL: REFLEXÕES SOBRE PERSPECTIVAS DEMOCRÁTICAS

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    Este artigo objetiva, a partir da síntese das categorias Estado e sociedade civil nos autores clássicos e contemporâneos situar os conselhos gestores de políticas públicas, bem como refletir sobre as questões que envolvem a participação democrática da sociedade civil no Brasil no contexto desses espaços. Para isso ao longo do texto os conselhos são compreendidos enquanto espaço de interlocução entre a sociedade civil e o Estado, tendo como uma de suas finalidades o controle social das políticas públicas. De igual sorte consideramos que a participação da sociedade civil se configura enquanto prática necessária na consolidação de aspectos que compõem a democracia em diferentes níveis de gestão social e ainda possibilita fortalecer e aprofundar a democracia, com vistas a uma cidadania integral com acesso aos direitos civis, políticos e sociai

    Methylation decrease of BECN1 gene induced by phytochemical Indicaxantin in Caco2 cells: an epigenetic hypothesis of autophagy

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    Autophagy is a highly conserved catabolic process that degrades and recycles intracellular components through the lysosomes [1]. The role of this process in tumorigenesis and tumor progression is controversial: in the early stages, it can block tumor growth and conversely it can promote its progression in the later stages [2]. The tumor suppressor BECN1 gene, encodes the protein Beclin 1, a marker of autophagy down-regulated in several types of cancer, such as colorectal cancer [3]. There are a lot of both genetic and environmental risk factors for colorectal cancer, including diet: for this reason, in accordance with epidemiological studies, consumption of foods rich in phytochemicals is widely promoted. The betalain indicaxantin (Ind) is a phytochemical from the Opuntia Ficus-Indica fruit having several biological activities, such as antioxidant, anti-inflammatory. It showed antiproliferative and proapoptotic effects in colorectal adenocarcinoma (Caco2) cells where was able to regulate gene expression through modulation of methylation state of DNA at CpG islands [4]. For the first time, using Methylation-Sensitive Restriction Endonuclease PCR (MSRE-PCR), we report that Ind (50 e 100 µM) decreases the methylation of BECN1 promoter in Caco2 cells, to the same extent as 5-azacytidine (Zcyd, positive control). Interestingly, colorimetric detection of DNA Methyltransferases activity, indicates that Ind reduced the activity of these enzymes, like Zcyd did. These preliminary data, indicating that Ind is able to decrease the methylation of BECN1 gene, allow us to propose an epigenetic hypothesis of autophagy regulation in Caco2 cells

    Up-Regulation of the Nrf2/HO-1 Antioxidant Pathway in Macrophages by an Extract from a New Halophilic Archaea Isolated in Odiel Saltworks

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    The production of reactive oxygen species (ROS) plays an important role in the progression of many inflammatory diseases. The search for antioxidants with the ability for scavenging free radicals from the body cells that reduce oxidative damage is essential to prevent and treat these pathologies. Haloarchaea are extremely halophilic microorganisms that inhabit hypersaline environments, such as saltworks or salt lakes, where they have to tolerate high salinity, and elevated ultraviolet (UV) and infrared radiations. To cope with these extreme conditions, haloarchaea have developed singular mechanisms to maintain an osmotic balance with the medium, and are endowed with unique compounds, not found in other species, with bioactive properties that have not been fully explored. This study aims to assess the potential of haloarchaea as a new source of natural antioxidant and anti-inflammatory agents. A carotenoid-producing haloarchaea was isolated from Odiel Saltworks (OS) and identified on the basis of its 16S rRNA coding gene sequence as a new strain belonging to the genus Haloarcula. The Haloarcula sp. OS acetone extract (HAE) obtained from the biomass contained bacterioruberin and mainly C18 fatty acids, and showed potent antioxidant capacity using ABTS assay. This study further demonstrates, for the first time, that pretreatment with HAE of lipopolysaccharide (LPS)-stimulated macrophages results in a reduction in ROS production, a decrease in the pro-inflammatory cytokines TNF-α and IL-6 levels, and up-regulation of the factor Nrf2 and its target gene heme oxygenase-1 (HO-1), supporting the potential of the HAE as a therapeutic agent in the treatment of oxidative stress-related inflammatory diseases.This research was funded by the Operative FEDER Program-Andalucía 2014-2020 (US-1380844 and UHU-1257518), Spanish Agencia Estatal de Investigación (PID2019-110438RBC22-AEI/FEDER), the Andalusian government (I+D+i-JA-PAIDI-Retos projects 2020-PY20) and the “VII Plan Propio de Investigación y Transferencia” of The University of Seville. The work was partially funded by national funds from Fundação para a Ciência e a Tecnologia (FCT, Portugal) in the scope of the projects UIDB/04565/2020 and UIDP/04565/2020 of the Research Unit iBB-Institute for Bioengineering and Biosciences, and of the project LA/P/0140/2020 of the i4HB-Associate Laboratory Institute for Health and Bioeconomy. P.G.-V acknowledges financial support from the “Margarita Salas” grant for the training of young doctors, University of Huelva
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