40 research outputs found

    L-Tyr-Induced Phosphorylation of Tyrosine Hydroxylase at Ser40: An Alternative Route for Dopamine Synthesis and Modulation of Na+/K+-ATPase in Kidney Cells

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    Background/Aims: Dopamine (DA) is a natriuretic hormone that inhibits renal sodium reabsorption, being Angiotensin II (Ang II) its powerful counterpart. These two systems work together to maintain sodium homeostasis and consequently, the blood pressure (BP) within normal limits. We hypothesized that L-tyrosine (L-tyr) or L-dihydroxyphenylalanine (L-dopa) could inhibit the Na+/K+-ATPase activity. We also evaluated whether L-tyr treatment modulates Tyrosine Hydroxylase (TH). Methods: Experiments involved cultured LLCPK1 cells treated with L-tyr or L-dopa for 30 minutes a 37°C. In experiments on the effect of Dopa Descarboxylase (DDC) inhibition, cells were pre incubated for 15 minutes with 3-Hydroxybenzylhydrazine dihydrochloride (HBH), and them L-dopa was added for 30 minutes. Na+/K+-ATPase activity was quantified colorimetrically. We used immunoblotting and immunocytochemistry to identify the enzymes TH, DDC and the dopamine receptor D1R in LLCPK1 cells. TH activity was accessed by immunoblotting (increase in the phosphorylation). TH and DDC activities were also evaluated by the modulation of the Na+/K+-ATPase activity, which can be ascribed to the synthesis of dopamine. Results: LLCPK1 cells express the required machinery for DA synthesis: the enzymes TH, and (DDC) as well as its receptor D1R, were detected in control steady state cells. Cells treated with L-tyr or L-dopa showed an inhibition of the basolateral Na+/K+-ATPase activity. We can assume that DA formed in the cytoplasm from L-tyr or L-dopa led to inhibition of the Na+/K+-ATPase activity compared to control. L-tyr treatment increases TH phosphorylation at Ser40 by 100%. HBH, a specific DDC inhibitor; BCH, a LAT2 inhibitor; and Sch 23397, a specific D1R antagonist, totally suppressed the inhibition of Na+/K+-ATPase activity due to L-dopa or L-tyr administration, as indicated in the figures. Conclusion: The results indicate that DA formed mainly from luminal L-tyr or L-dopa uptake by LAT2, can inhibit the Na+/K+-ATPase. In addition, our results showed for the very first time that TH activity is also significantly increased when the cells were exposed to L-tyr

    VizLattes: a tool for relevance analysis from scientific co-authorship networks

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    Social network data typically carry attribute information associated with the individuals and to their relationships. Such interconnected information can be useful to identify groups of individuals sharing common attribute properties and also to investigate the behaviour of particular individuals in a global network scenario. Different approaches have been introduced to extract and identify information of interest in social networks, and community identification is one of them. Some methods focus on identifying groups or communities of individuals based on their relationships, while others try to identify groups of individuals based on the common information they share. Integrating both approaches is not straightforward, as different mathematical and computational must be implemented and integrated into a unified framework. In this paper we approach this problem and propose a new method to identify underlying communities in a network, while highlighting the information shared by their components. Our solution relies on a single unified mathematical method. As a proof-of-concept, we have applied the proposed method to scientific co-authorship networks extracted from the wellknown Lattes Platform made available by CNPq, the Brazilian national science funding agency. We use textual information on the co-authors and their papers as focus attributes. We show that the method supports both community detection and also the identification of thematic paths, underlying topics and relevant authors characterizing distinct academic communities. The results presented show that this approach can be quite useful for exploration and understanding of academic collaboration networks.CAPESCNPqFAPES

    Epidemiologic profile of juvenile-onset compared to adult-onset spondyloarthritis in a large Brazilian cohort

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    Objective To analyze the clinical and epidemiologic characteristics of juvenile-onset spondyloarthritis (SpA) (< 16 years) and compare them with a group of adult-onset (≥ 16 years) SpA patients. Patients and methods Prospective, observational and multicentric cohort with 1,424 patients with the diagnosis of SpA according to the European Spondyloarthropathy Study Group (ESSG) submitted to a common protocol of investigation and recruited in 29 reference centers participants of the Brazilian Registry of Spondyloarthritis (RBE – Registro Brasileiro de Espondiloartrites). Patients were divided in two groups: age at onset<16 years (JOSpA group) and age at onset ≥ 16 years (AOSpA group). Results Among the 1,424 patients, 235 presented disease onset before 16 years (16.5%). The clinical and epidemiologic variables associated with JOSpA were male gender (p<0.001), lower limb arthritis (p=0.001), enthesitis (p=0.008), anterior uveitis (p=0.041) and positive HLA-B27 (p=0.017), associated with lower scores of disease activity (Bath Ankylosing Spondylitis Disease Activity Index – BASDAI; p=0.007) and functionality (Bath Ankylosing Spondylitis Functional Index – BASFI; p=0.036). Cutaneous psoriasis (p<0.001), inflammatory bowel disease (p=0.023), dactylitis (p=0.024) and nail involvement (p=0.004) were more frequent in patients with adult-onset SpA. Conclusions Patients with JOSpA in this large Brazilian cohort were characterized predominantly by male gender, peripheral involvement (arthritis and enthesitis), positive HLA-B27 and lower disease scores.Objetivo Analisar as características clínicas e epidemiológicas das espondiloartrites (EpA) de início juvenil (< 16 anos) e compará-las com um grupo de pacientes com EspA de início na vida adulta (≥ 16 anos). Pacientes e métodos Coorte prospectiva, observacional e multicêntrica com 1.424 pacientes com diagnóstico de EspA de acordo com o European Spondyloarthropathy Study Group (ESSG) submetidos a um protocolo comum de investigação e recrutados em 29 centros de referência participantes do Registro Brasileiro de Espondiloartrites (RBE). Os pacientes foram divididos em dois grupos: idade no início<16 anos (grupo EspAiJ) e idade no início ≥ 16 anos. Resultados Entre os 1.424 pacientes, 235 manifestaram o início da doença antes dos 16 anos (16,5%). As variáveis clínicas e epidemiológicas associadas com a EspAiJ foram: gênero masculino (p<0,001), artrite em membro inferior (p=0,001), entesite (p=0,008), uveíte anterior (p=0,041) e HLA-B27 positivo (p=0,017), em associação com escores mais baixos de atividade da doença (Bath Ankylosing Spondylitis Disease Activity Index – BASDAI; p=0,007) e de capacidade funcional (Bath Ankylosing Spondylitis Functional Index – BASFI; p=0,036). A psoríase cutânea (p<0,001), a doença inflamatória intestinal (p=0,023), a dactilite (p=0,024) e o envolvimento ungueal (p=0,004) foram mais frequentes em pacientes com EspA de início na vida adulta. Conclusões Nessa grande coorte brasileira, os pacientes com EspAiJ se caracterizavam predominantemente pelo gênero masculino, envolvimento periférico (artrite e entesite), HLA-B27 positivo e escores de doença mais baixos.Universidade Federal de PernambucoInsper Instituto de Educação e PesquisaUniversidade de São Paulo Faculdade de Medicina Divisão de ReumatologiaUniversidade de BrasíliaHospital Geral de GoiâniaUniversidade de CampinasUniversidade Federal do AmazonasPontifícia Universidade CatólicaHospital Evangélico de CuritibaUniversidade Federal do Rio de JaneiroUniversidade Estadual do Rio de JaneiroFaculdade de Medicina de São José do Rio PretoUniversidade Federal do ParanáHospital Geral de FortalezaSanta Casa do Rio de JaneiroSanta Casa de São PauloHospital de Base do Distrito FederalUniversidade Federal do Mato Grosso do SulUniversidade Federal do Rio Grande do SulFaculdade de Medicina Souza MarquesHospital do Servidor Público EstadualUniversidade de São Paulo Instituto de Ortopedia e TraumatologiaUniversidade Federal de Santa CatarinaUniversidade Federal de São Paulo (UNIFESP)Santa Casa de Belo HorizonteUniversidade Federal de Minas GeraisUniversidade Federal do CearáEscola de Medicina e Saúde PúblicaUniversidade Federal do ParáUniversidade Federal do Espírito SantoUNIFESPSciEL

    Erratum of Enteropathic arthritis in Brazil: data from the Brazilian registry of spondyloarthritis

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    Universidade Federal de Minas GeraisInstituto Insper de Educação e PesquisaUniversidade de São Paulo Disciplina de ReumatologiaUniversidade de BrasíliaHospital Geral de GoiâniaUniversidade de CampinasUniversidade Federal do AmazonasPontifícia Universidade CatólicaFaculdade de Medicina de São José do Rio PretoHospital Evangélico de CuritibaUniversidade Federal do Rio de JaneiroUniversidade Federal do ParanáHospital Geral de FortalezaUniversidade Estadual do Rio de JaneiroSanta Casa do Rio de JaneiroSanta Casa de São PauloHospital de BaseUniversidade Federal do Mato Grosso do SulUniversidade Federal de PernambucoUniversidade Federal do Rio Grande do SulFaculdade de Medicina Souza MarquesHospital do Servidor Público EstadualUniversidade de São Paulo Instituto de Ortopedia e TraumatologiaUniversidade Federal de Santa CatarinaUniversidade Federal de São Paulo (UNIFESP)Santa Casa de Belo HorizonteUniversidade Federal do CearáEscola de Medicina e Saúde PúblicaUniversidade Federal do ParáUniversidade Federal do Espírito SantoUNIFESPSciEL

    Enteropathic arthritis in Brazil: data from the brazilian registry of spondyloarthritis

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    Inflammatory bowel diseases (Crohn's disease and ulcerative rectocolitis) have extraintestinal manifestations 25% of the patients, with the most common one being the enteropathic arthritis. METHODS: Prospective, observational, multicenter study with patients from 29 reference centers participating in the Brazilian Registry of Spondyloarthritis (RBE), which incorporates the RESPONDIA (Ibero-American Registry of Spondyloarthritis) group. Demographic and clinical data were collected from 1472 patients and standardized questionnaires for the assessment of axial mobility, quality of life, enthesitic involvement, disease activity and functional capacity were applied. Laboratory and radiographic examinations were performed. The aim of this study is to compare the clinical, epidemiological, genetic, imaging, treatment and prognosis characteristics of patients with enteropathic arthritis with other types of spondyloarthritis in a large Brazilian cohort. RESULTS: A total of 3.2% of patients were classified as having enteroarthritis, 2.5% had spondylitis and 0.7%, arthritis (peripheral predominance). The subgroup of individuals with enteroarthritis had a higher prevalence in women (P < 0.001), lower incidence of inflammatory axial pain (P < 0.001) and enthesitis (P = 0.004). HLA-B27 was less frequent in the group with enteroarthritis (P = 0.001), even when considering only those with the pure axial form. There was a lower prevalence of radiographic sacroiliitis (P = 0.009) and lower radiographic score (BASRI) (P = 0.006) when compared to patients with other types of spondyloarthritis. They also used more corticosteroids (P < 0.001) and sulfasalazine (P < 0.001) and less non-steroidal anti-inflammatory drugs (P < 0.001) and methotrexate (P = 0.001). CONCLUSION: There were differences between patients with enteroarthritis and other types of spondyloarthritis, especially higher prevalence of females, lower frequency of HLA-B27, associated with less severe axial involvement.As doenças inflamatórias intestinais (doença de Crohn e retocolite ulcerativa) apresentam manifestações extraintestinais em um quarto dos pacientes, sendo a mais comum a artrite enteropática. MÉTODOS: Estudo prospectivo, observacional e multicêntrico, realizado com pacientes de 29 centros de referência participantes do Registro Brasileiro de Espondiloartrites (RBE), que se incorpora ao grupo RESPONDIA (Registro Ibero-americano de Espondiloartrites). Dados demográficos e clínicos de 1472 pacientes foram colhidos, e aplicaram-se questionários padronizados de avaliação de mobilidade axial, de qualidade de vida, de envolvimento entesítico, de atividade de doença e de capacidade funcional. Exames laboratoriais e radiográficos foram realizados. Objetivamos, neste presente artigo, comparar as características clínicas, epidemiológicas, genéticas, imagenológicas, de tratamento e prognóstico de enteroartríticos com os outros espondiloartríticos nesta grande coorte brasileira. RESULTADOS: Foram classificados como enteroartrite 3,2% dos pacientes, sendo que 2,5% tinham espondilite e 0,7%, artrite (predomínio periférico). O subgrupo de indivíduos com enteroartrite apresentava maior prevalência de mulheres (P < 0,001), menor incidência de dor axial inflamatória (P < 0,001) e de entesite (P = 0,004). O HLA-B27 foi menos frequente no grupo de enteroartríticos (P = 0,001), mesmo se considerado apenas aqueles com a forma axial pura. Houve menor prevalência de sacroiliíte radiológica (P = 0,009) e também menor escore radiográfico (BASRI) (P = 0,006) quando comparado aos pacientes com as demais espondiloartrites. Também fizeram mais uso de corticosteroides (P < 0,001) e sulfassalasina (P < 0,001) e menor uso de anti-inflamatórios não hormonais (P < 0,001) e metotrexato (P = 0,001). CONCLUSÃO: Foram encontradas diferenças entre as enteroartrites e as demais espondiloartrites, principalmente maior prevalência do sexo feminino, menor frequência do HLA-B27, associados a uma menor gravidade do acometimento axial.Universidade Federal de Minas GeraisInstituto Insper de Educação e PesquisaUniversidade de São PauloUniversidade de BrasíliaHospital Geral de GoiâniaUniversidade de CampinasUniversidade Federal do AmazonasPontifícia Universidade CatólicaFaculdade de Medicina de São José do Rio PretoHospital Evangélico de CuritibaUniversidade Federal do Rio de JaneiroUniversidade Federal do ParanáHospital Geral de FortalezaUniversidade Estadual do Rio de JaneiroSanta Casa do Rio de JaneiroSanta Casa de São PauloHospital de BaseUniversidade Federal do Mato Grosso do SulUniversidade Federal de PernambucoUniversidade Federal do Rio Grande do SulFaculdade de Medicina Souza MarquesHospital do Servidor Público EstadualUniversidade de São Paulo Instituto de Ortopedia e TraumatologiaUniversidade Federal de Santa CatarinaUniversidade Federal de São Paulo (UNIFESP)Santa Casa de Belo HorizonteUniversidade Federal do CearáEscola de Medicina e Saúde PúblicaUniversidade Federal do ParáUniversidade Federal do Espírito SantoUNIFESPSciEL

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
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