2,111 research outputs found

    The MMP-1/PAR-1 Axis Enhances Proliferation and Neuronal Differentiation of Adult Hippocampal Neural Progenitor Cells

    Get PDF
    Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that play a role in varied forms of developmental and postnatal neuroplasticity. MMP substrates include protease-activated receptor-1 (PAR-1), a G-protein coupled receptor expressed in hippocampus. We examined proliferation and differentiation of adult neural progenitor cells (aNPCs) from hippocampi of mice that overexpress the potent PAR-1 agonist MMP-1. We found that, as compared to aNPCs from littermate controls, MMP-1 tg aNPCs display enhanced proliferation. Under differentiating conditions, these cells give rise to a higher percentage of MAP-2+ neurons and a reduced number of oligodendrocyte precursors, and no change in the number of astrocytes. The fact that these results are MMP and PAR-1 dependent is supported by studies with distinct antagonists. Moreover, JSH-23, an inhibitor of NF-κB p65 nuclear translocation, counteracted both the proliferation and differentiation changes seen in MMP-1 tg-derived NPCs. In complementary studies, we found that the percentage of Sox2+ undifferentiated progenitor cells is increased in hippocampi of MMP-1 tg animals, compared to wt mice. Together, these results add to a growing body of data suggesting that MMPs are effectors of hippocampal neuroplasticity in the adult CNS and that the MMP-1/PAR-1 axis may play a role in neurogenesis following physiological and/or pathological stimuli

    Mineralogical controls on mobility of rare earth elements in acid mine drainage environments

    Get PDF
    Supplementary data related to this article can be found at https://doi.org/10.1016/j.chemosphere.2018.04.095.Rare earth elements (REE) were analyzed in river waters, acid mine waters, and extracts of secondary precipitates collected in the Iberian Pyrite Belt. The obtained concentrations of the REE in river water and mine waters (acid mine drainage - AMD) were in the range of 0.57 μg/L (Lu) and 2579 μg/L (Ce), which is higher than previously reported in surface waters from the Iberian Pyrite Belt, but are comparable with previous findings from AMD worldwide. Total REE concentrations in river waters were ranged between 297 μg/L (Cobica River) and 7032 μg/L (Trimpancho River) with an average of 2468 μg/L. NASC (North American Shale Composite) normalized REE patterns for river and acid mine waters show clear convex curvatures in middle-REE (MREE) with respect to light- and heavy-REE. During the dissolution experiments of AMD-precipitates, heavy-REE and middle-REE generate the most enriched patterns in the solution. A small number of precipitates did not display MREE enrichment (an index Gdn/Lun < 1.0) in NASC normalized pattern and produced relatively lower REE concentrations in extracts. Additionally, very few samples, which mainly contained aluminum sulfates, e.g., pickeringite and alunogen, displayed light-REE enrichment relative to heavy-REE (HREE). In general, the highest retention of REE occurs in samples enriched in magnesium (epsomite or hexahydrite) and aluminum sulfates, mainly pickeringite.Financial support was provided by the Andalusian Autonomous Government Excellence Project, code P06-RNM-02167. This work was also co-funded by the European Union through the European Regional Development Fund, based on COMPETE 2020, project ICT (UID/GEO/04683/2013), reference POCI-01-0145-FEDER-007690, national funds provided by FCT. Post-Doctoral Fellowship through Erasmus Mundus SAT program and Young Scientist Research Grant (SEAS-2015−14) of the National University of Mongolia were supported for T.-O. Soyol-Erdene. The authors also appreciate the valuable comments and suggestions made by the anonymous reviewers

    Affective state dependence and relative trait stability of perfectionism in sleep disturbances

    Get PDF
    OBJECTIVE: To evaluate the degree of absolute change, relative stability and state dependence of trait perfectionism in sleep disturbances in a sample of university students. METHOD: Participants completed the Multidimensional Perfectionism Scale and two items concerning sleep difficulties. The mean age at T0 (baseline) was 19.59 years (SD = 1.61, range = 17-25) and 62.5% of the sample were female. RESULTS: Absolute changes in self-oriented and socially-prescribed perfectionism were found. Relative stability was found for all perfectionism dimensions. Prior and concurrent sleep disturbances explained a significant amount of variance in perfectionism. Controlling for the effects of sleep measures, prior selforiented perfectionism and other-oriented perfectionism were the only significant predictors of subsequent self-oriented perfectionism and otheroriented perfectionism, at T1 and T2. Difficulties falling asleep at T1 and socially-prescribed perfectionism at T0 were significant predictors of socially-prescribed perfectionism at T1. CONCLUSION: Despite significant changes in perfectionism mean scores over the follow-up, the correlation analyses demonstrated that participants remained quite stable in regard to their relative levels of perfectionism. As concurrent difficulties initiating sleep also predicted concurrent socially-prescribed perfectionism, this seems to be one dimension of perfectionism with trait-state characteristics.OBJETIVOS: Avaliar o grau de mudança absoluta, de estabilidade relativa e dependência do estado do perfeccionismo nas perturbações de sono numa amostra de estudantes universitários. MÉTODO: Os sujeitos completaram a Escala Multidimensional do Perfeccionismo e dois itens sobre dificuldades em dormir. Os dados foram recolhidos em três momentos de avaliação, separados por um intervalo de um ano acadêmico. A idade média dos sujeitos noT0 era de 19,59 anos (DP = 1,61, variação = 17-25); 62,5% eram mulheres. RESULTADOS: Foram encontradas ao longo do follow-up mudanças absolutas para o Perfeccionismo Autoorientado e para o Perfeccionismo Socialmente Prescrito. Foi encontrada estabilidade relativa para todas as dimensões do perfeccionismo. As dificuldades de sono prévias e concorrentes explicaram significativamente a variância do perfeccionismo. Controlando o efeito das dificuldades em dormir, o Perfeccionismo Autoorientado e o POO prévios foram os únicos preditores significativos de Perfeccionismo Autoorientado e POO subsequente (T1 e T2). As dificuldades em iniciar o sono no T1 e o Perfeccionismo Socialmente Prescrito prévio (T0) revelaram-se preditores significativos dePerfeccionismoSocialmente PrescritonoT1. CONCLUSÃO: Apesar das mudanças significativas nas pontuações médias de perfeccionismo ao longo do follow-up, as análises de correlação demonstraram que os participantes permaneceramrelativamenteestáveisnosseusníveisdeperfeccionismo.Umavezque asdificuldades em iniciar o sono concorrentes serevelaram um preditor significativo de Perfeccionismo Socialmente Prescrito, o Perfeccionismo Socialmente Prescrito é a dimensão do perfeccionismo que possui características traço-estado

    Fuzzy modelling of acid mine drainage environments using geochemical, ecological and mineralogical indicators

    Get PDF
    Fuzzy logic was applied to model acid mine drainage (AMD) and to obtain a classification index of the environmental impact in a contaminated riverine system. The data set used to develop this fuzzy model (a fuzzy classifier) concerns an abandoned mine in Northern Portugal— Valdarcas mining site. Here, distinctive drainage environments (spatial patterns) can be observed based on the AMD formed in the sulphide-rich waste-dumps. Such environments were established, as the effluent flows through the mining area, using several kinds of indicators. These are physical–chemical, ecological and mineralogical parameters, being expressed in a quantitative or qualitative basis. The fuzzy classifier proposed in this paper is a min– max fuzzy inference system, representing the spatial behaviour of those indicators, using the AMD environments as patterns. As they represent different levels (classes) of contamination, the fuzzy classifier can be used as a tool, allowing a more reasonable approach, compared with classical models, to characterize the environmental impact caused by AMD. In a general way it can be applied to other sites where sulphide-rich waste-dumps are promoting the pollution of superficial water through the generation of AMD

    Ferromagnetic Levan Composite: An Affinity Matrix to Purify Lectin

    Get PDF
    A simple and inexpensive procedure used magnetite and levan to synthesize a composite recovered by a magnetic field. Lectins from Canavalia ensiformis (Con A) and Cratylia mollis (Cramoll 1 and Cramoll 1, 4) did bind specifically to composite. The magnetic property of derivative favored washing out contaminating proteins and recovery of pure lectins with glucose elution. Cramoll 1 was purified by this affinity binding procedure in two steps instead of a previous three-step protocol with ammonium sulfate fractionation, affinity chromatography on Sephadex G-75, and ion exchange chromatography through a CM-cellulose column

    Precision Measurement of KS Meson Lifetime with the KLOE detector

    Get PDF
    Using a large sample of pure, slow, short lived K0 mesons collected with KLOE detector at DaFne, we have measured the KS lifetime. From a fit to the proper time distribution we find tau = (89.562 +- 0.029_stat +- 0.043_syst) ps. This is the most precise measurement today in good agreement with the world average derived from previous measurements. We observe no dependence of the lifetime on the direction of the Ks.Comment: 5 pages, 7 figure

    A Rapid and Simple Procedure for the Establishment of Human Normal and Cancer Renal Primary Cell Cultures from Surgical Specimens

    Get PDF
    The kidney is a target organ for the toxicity of several xenobiotics and is also highly susceptible to the development of malignant tumors. In both cases, in vitro studies provide insight to cellular damage, and represent adequate models to study either the mechanisms underlying the toxic effects of several nephrotoxicants or therapeutic approaches in renal cancer. The development of efficient methods for the establishment of human normal and tumor renal cell models is hence crucial. In this study, a technically simple and rapid protocol for the isolation and culture of human proximal tubular epithelial cells and human renal tumor cells from surgical specimens is presented. Tumor and normal tissues were processed by using the same methodology, based on mechanical disaggregation of tissue followed by enzymatic digestion and cell purification by sequential sieving. The overall procedure takes roughly one hour. The resulting cell preparations have excellent viabilities and yield. Establishment of primary cultures from all specimens was achieved successfully. The origin of primary cultured cells was established through morphological evaluation. Normal cells purity was confirmed by immunofluorescent staining and reverse transcription-polymerase chain reaction analysis for expression of specific markers

    Mapping social work across 10 countries: Structure, intervention, identity and challenges

    Get PDF
    An emerging global consciousness and rising attention given to international social work development has seen the recognition of comparative research within the profession. Understanding the functioning and organisation of social work within various country contexts is critical in order to formulate knowledge around its overall impact, successes and challenges, allowing social workers to learn from one another and build professional consolidation. The profession is mapped out in 10 countries, reflecting on its structure, identity and development. Although the profession is developing globally, it is also experiencing significant challenges. Key insights, conclusions and recommendations for future research are presented
    corecore