101 research outputs found

    New records and detailed distribution and abundance of selected arthropod species collected between 1999 and 2011 in Azorean native forests

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    [Background] In this contribution we present detailed distribution and abundance data for arthropod species identified during the BALA ¿ Biodiversity of Arthropods from the Laurisilva of the Azores (1999-2004) and BALA2 projects (2010-2011) from 18 native forest fragments in seven of the nine Azorean islands (all excluding Graciosa and Corvo islands, which have no native forest left).[New information] Of the total 286 species identified, 81% were captured between 1999 and 2000, a period during which only 39% of all the samples were collected. On average, arthropod richness for each island increased by 10% during the time frame of these projects. The classes Arachnida, Chilopoda and Diplopoda represent the most remarkable cases of new island records, with more than 30% of the records being novelties. This study stresses the need to expand the approaches applied in these projects to other habitats in the Azores, and more importantly to other less surveyed taxonomic groups (e.g. Diptera and Hymenoptera). These steps are fundamental for getting a more accurate assessment of biodiversity in the archipelago.AMCS was supported by a Marie Curie Intra-European Fellowship (IEF 331623 ‘COMMSTRUCT’) and by a Juan de la Cierva Fellowship (IJCI-2014-19502) funded by the Spanish ‘Ministerio de Economía y Competitividad’.Peer Reviewe

    Changes in calcium dynamics following the reversal of the sodium-calcium exchanger have a key role in AMPA receptor-mediated neurodegeneration via calpain activation in hippocampal neurons

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    Proteolytic cleavage of the Na(+)/Ca(2+) exchanger (NCX) by calpains impairs calcium homeostasis, leading to a delayed calcium overload and excitotoxic cell death. However, it is not known whether reversal of the exchanger contributes to activate calpains and trigger neuronal death. We investigated the role of the reversal of the NCX in Ca(2+) dynamics, calpain activation and cell viability, in alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor-stimulated hippocampal neurons. Selective overactivation of AMPA receptors caused the reversal of the NCX, which accounted for approximately 30% of the rise in intracellular free calcium concentration ([Ca(2+)](i)). The NCX reverse-mode inhibitor, 2-[2-[4-(4-nitrobenzyloxy)phenyl]ethyl]isothiourea (KB-R7943), partially inhibited the initial increase in [Ca(2+)](i), and prevented a delayed increase in [Ca(2+)](i). In parallel, overactivation of AMPA receptors strongly activated calpains and led to the proteolysis of NCX3. KB-R7943 prevented calpain activation, cleavage of NCX3 and was neuroprotective. Silencing of NCX3 reduced Ca(2+) uptake, calpain activation and was neuroprotective. Our data show for the first time that NCX reversal is an early event following AMPA receptor stimulation and is linked to the activation of calpains. Since calpain activation subsequently inactivates NCX, causing a secondary Ca(2+) entry, NCX may be viewed as a new suicide substrate operating in a Ca(2+)-dependent loop that triggers cell death and as a target for neuroprotectio

    C2-phytoceramide perturbs lipid rafts and cell integrity in Saccharomyces cerevisiae in a sterol-dependent manner

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    Specific ceramides are key regulators of cell fate, and extensive studies aimed to develop therapies based on ceramide-induced cell death. However, the mechanisms regulating ceramide cytotoxicity are not yet fully elucidated. Since ceramides also regulate growth and stress responses in yeast, we studied how different exogenous ceramides affect yeast cells. C2-phytoceramide, a soluble form of phytoceramides, the yeast counterparts of mammalian ceramides, greatly reduced clonogenic survival, particularly in the G2/M phase, but did not induce autophagy nor increase apoptotic markers. Rather, the loss of clonogenic survival was associated with PI positive staining, disorganization of lipid rafts and cell wall weakening. Sensitivity to C2-phytoceramide was exacerbated in mutants lacking Hog1p, the MAP kinase homolog of human p38 kinase. Decreasing sterol membrane content reduced sensitivity to C2-phytoceramide, suggesting sterols are the targets of this compound. This study identified a new function of C2-phytoceramide through disorganization of lipid rafts and induction of a necrotic cell death under hypo-osmotic conditions. Since lipid rafts are important in mammalian cell signaling and adhesion, our findings further support pursuing the exploitation of yeast to understand the basis of synthetic ceramides' cytotoxicity to provide novel strategies for therapeutic intervention in cancer and other diseases.This work was supported by Fundacao para a Ciencia e Tecnologia through projects PTDC/BIA-BCM/69448/2006 and PEst-C/BIA/UI4050/2011, and fellowships to A. P. (SFRH/BPD/65003) and F. A. (SFRH/BD/80934/2011), as well as by FEDER through POFC - COMPETE. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    The Recognition of N-Glycans by the Lectin ArtinM Mediates Cell Death of a Human Myeloid Leukemia Cell Line

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    ArtinM, a d-mannose-binding lectin from Artocarpus heterophyllus (jackfruit), interacts with N-glycosylated receptors on the surface of several cells of hematopoietic origin, triggering cell migration, degranulation, and cytokine release. Because malignant transformation is often associated with altered expression of cell surface glycans, we evaluated the interaction of ArtinM with human myelocytic leukemia cells and investigated cellular responses to lectin binding. The intensity of ArtinM binding varied across 3 leukemia cell lines: NB4>K562>U937. The binding, which was directly related to cell growth suppression, was inhibited in the presence of Manα1-3(Manα1-6)Manβ1, and was reverted in underglycosylated NB4 cells. ArtinM interaction with NB4 cells induced cell death (IC50 = 10 µg/mL), as indicated by cell surface exposure of phosphatidylserine and disruption of mitochondrial membrane potential unassociated with caspase activation or DNA fragmentation. Moreover, ArtinM treatment of NB4 cells strongly induced reactive oxygen species generation and autophagy, as indicated by the detection of acidic vesicular organelles in the treated cells. NB4 cell death was attributed to ArtinM recognition of the trimannosyl core of N-glycans containing a ß1,6-GlcNAc branch linked to α1,6-mannose. This modification correlated with higher levels of N-acetylglucosaminyltransferase V transcripts in NB4 cells than in K562 or U937 cells. Our results provide new insights into the potential of N-glycans containing a β1,6-GlcNAc branch linked to α1,6-mannose as a novel target for anti-leukemia treatment

    Guidelines for the management of neuroendocrine tumours by the Brazilian gastrointestinal tumour group

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    Neuroendocrine tumours are a heterogeneous group of diseases with a significant variety of diagnostic tests and treatment modalities. Guidelines were developed by North American and European groups to recommend their best management. However, local particularities and relativisms found worldwide led us to create Brazilian guidelines. Our consensus considered the best feasible strategies in an environment involving more limited resources. We believe that our recommendations may be extended to other countries with similar economic standards.Univ Sao Paulo, Inst Canc Estado Sao Paulo, BR-01246000 Sao Paulo, BrazilUniv Sao Paulo, Fac Med, Dept Radiol & Oncol, BR-01246903 Sao Paulo, BrazilHosp Sirio Libanes, BR-01308050 Sao Paulo, BrazilHosp Moinhos de Vento Porto Alegre, BR-90035000 Porto Alegre, RS, BrazilOncoctr, BR-30360680 Belo Horizonte, MG, BrazilUniv Fed Rio Grande do Sul, Dept Cirurgia, BR-90040060 Porto Alegre, RS, BrazilHosp Clin Porto Alegre, BR-90035903 Porto Alegre, RS, BrazilUniv Fed Ceara, Fac Med, Dept Fisiol & Farmacol, BR-60020180 Fortaleza, Ceara, BrazilHosp Univ Walter Cantidio, BR-60430370 Fortaleza, Ceara, BrazilInst Nacl Canc, BR-20230240 Rio De Janeiro, BrazilUniv Sao Paulo, Fac Med, Disciplina Endocrinol & Metabol, BR-01246903 Sao Paulo, BrazilAC Camargo Canc Ctr, Dept Surg, BR-01509010 Sao Paulo, BrazilUniv Sao Paulo, Fac Med, Dept Gastroenterol, Sao Paulo, BrazilUniv Fed Ciencias Saude Porto Alegre, BR-90050170 Porto Alegre, RS, BrazilHosp Albert Einstein, BR-05652900 Sao Paulo, BrazilHosp Base, Fac Med Sao Jose do Rio Preto, BR-15090000 Sao Paulo, BrazilSanta Casa Sao Jose do Rio Preto, BR-15025500 Sao Jose Do Rio Preto, BrazilPontificia Univ Catolica Parana, Hosp Erasto Gaertner, BR-81520060 Curitiba, Parana, BrazilUniv Fed Rio Grande do Norte, BR-59300000 Natal, RN, BrazilUniv Sao Paulo, Inst Coracao, BR-05403900 Sao Paulo, BrazilAC Camargo Canc Ctr, Med Oncol, BR-01509010 Sao Paulo, BrazilUniv Fed Sao Paulo, Disciplina Gastroenterol, BR-04021001 Sao Paulo, BrazilHosp Sao Rafael, BR-41253190 Salvador, BA, BrazilHosp Canc Barretos, Dept Cirurgia Aparelho Digest Alto & Hepatobiliop, BR-14784400 Sao Paulo, BrazilUniv Sao Paulo, Fac Med, Dept Patol, BR-01246903 Sao Paulo, BrazilClin AMO, BR-1950640 Salvador, BA, BrazilHosp Sao Jose, BR-01323001 Sao Paulo, BrazilUniv Nove de Julho, BR-02111030 Sao Paulo, BrazilUniv Fed Sao Paulo, Disciplina Gastroenterol, BR-04021001 Sao Paulo, BrazilWeb of Scienc

    The institutions of archaic post-modernity and their organizational and managerial consequences: The case of Portugal

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    The long march of modernization of the Western societies tends to be presented as following a regular sequence: societies and institutions were pre-modern, and then they were modernized, eventually becoming post-modern. Such teleology may provide an incomplete or distorted narrative of societal evolution in many parts of the world, even in the ‘post-modern heartland’ of Western Europe, with Portugal being a case in point. The concept of archaic post-modernity has been developed by a philosopher, José Gil, to show how Portuguese institutions and organizations combine elements of pre-modernity and post-modernity. The notion of an archaic post-modernity is advanced in order to provide an alternative account of the modernization process, which enriches discussion of the varieties of capitalism. Differences in historical experiences create singularities that may be considered in the analysis of culture, management and organization

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): study protocol for a randomized controlled trial

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    BACKGROUND: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). METHODS/DESIGN: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH2O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure 6430 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. DISCUSSION: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration metho

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset
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