103 research outputs found

    MKP-1 mediates glucocorticoid-induced ERK1/2 dephosphorylation and reduction in pancreatic beta-cell proliferation in islets from early lactating mothers

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    Maternal pancreatic islets undergo a robust increase of mass and proliferation during pregnancy, which allows a compensation of gestational insulin resistance. Studies have described that this adaptation switches to a low proliferative status after the delivery. the mechanisms underlying this reversal are unknown, but the action of glucocorticoids (GCs) is believed to play an important role because GCs counteract the pregnancy-like effects of PRL on isolated pancreatic islets maintained in cell culture. Here, we demonstrate that ERK1/2 phosphorylation (phospho-ERK1/2) is increased in maternal rat islets isolated on the 19th day of pregnancy. Phospho-ERK1/2 status on the 3rd day after delivery (L3) rapidly turns to values lower than that found in virgin control rats (CTL). MKP-1, a protein phosphatase able to dephosphorylate ERK1/2, is increased in islets from L3 rats. Chromatin immunoprecipitation assay revealed that binding of glucocorticoid receptor (GR) to MKP-1 promoter is also increased in islets from L3 rats. in addition, dexamethasone (DEX) reduced phospho-ERK1/2 and increased MKP-1 expression in RINm5F and MIN-6 cells. Inhibition of transduction with cycloheximide and inhibition of phosphatases with orthovanadate efficiently blocked DEX-induced downregulation of phospho-ERK1/2. in addition, specific knockdown of MKP-1 with siRNA suppressed the downregulation of phosphoERK1/2 and the reduction of proliferation induced by DEX. Altogether, our results indicate that downregulation of phospho-ERK1/2 is associated with reduction in proliferation found in islets of early lactating mothers. This mechanism is probably mediated by GC-induced MKP-1 expression.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de PesquisaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ São Paulo, Inst Biomed Sci, Dept Physiol & Biophys, BR-05508 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, Diadema, SP, BrazilUniv Estadual Campinas, Fac Med Sci, Dept Pharmacol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, Diadema, SP, BrazilWeb of Scienc

    Antigenic and molecular evidence of Brucella sp.-associated epididymo-orchitis in frugivorous (Artibeus lituratus) and nectarivorous (Glossophaga soricina) bats in Brazil

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    This study included 47 free-ranging bats from the State of Minas Gerais, Brazil. Six bats (12.8%) had genital inflammatory lesions, and two of them (one Artibeus lituratus and one Glossophaga soricina, a frugivorous and a nectarivorous, respectively) were diagnosed with Brucella sp. infection through PCR, and antigens in intralesional macrophages were detected using immunohistochemistry

    Erro médico: a perspectiva de estudantes de medicina e direito

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    Nas últimas décadas, houve um crescimento das implicações em sociedade do erro médico, assunto em que se entrelaçam Medicina e Direito. Este estudo procurou conhecer a percepção de estudantes de Medicina e Direito sobre erro médico, avaliando nível de interesse e informação, e a necessidade de abordar o tema na graduação e como ela ocorre para cada área, na sua ótica. Estudo observacional descritivo transversal foi realizado na Universidade Federal de Juiz de Fora (MG) em 2008 com 185 alunos de Medicina e 119 de Direito. 88,7% dos alunos de Medicina (MED) e 92,4% de Direito (DIR) referiram conhecimento sobre erro médico. O interesse se dá por ser um tema muito discutido atualmente. Os alunos consideram necessária sua abordagem na graduação (97,8% MED e 94,9% DIR). É importante discutir um tema tão atual na graduação de Medicina e de Direito pela contribuição que pode ser oferecida para diminuir o ciclo vicioso de erros, iatrogenias e processos jurídicos, além de possibilitar uma reflexão acerca do papel da educação médica na construção ética de novos profissionais

    In Vitro Identification of Novel Plasminogen-Binding Receptors of the Pathogen Leptospira interrogans

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    Background: Leptospirosis is a multisystem disease caused by pathogenic strains of the genus Leptospira. We have reported that Leptospira are able to bind plasminogen (PLG), to generate active plasmin in the presence of activator, and to degrade purified extracellular matrix fibronectin. Methodology/Principal Findings: We have now cloned, expressed and purified 14 leptospiral recombinant proteins. The proteins were confirmed to be surface exposed by immunofluorescence microscopy and were evaluated for their ability to bind plasminogen (PLG). We identified eight as PLG-binding proteins, including the major outer membrane protein LipL32, the previously published rLIC12730, rLIC10494, Lp29, Lp49, LipL40 and MPL36, and one novel leptospiral protein, rLIC12238. Bound PLG could be converted to plasmin by the addition of urokinase-type PLG activator (uPA), showing specific proteolytic activity, as assessed by its reaction with the chromogenic plasmin substrate, D-Val-Leu-Lys 4-nitroanilide dihydrochloride. The addition of the lysine analog 6-aminocaproic acid (ACA) inhibited the protein-PLG interaction, thus strongly suggesting the involvement of lysine residues in plasminogen binding. The binding of leptospiral surface proteins to PLG was specific, dose-dependent and saturable. PLG and collagen type IV competed with LipL32 protein for the same binding site, whereas separate binding sites were observed for plasma fibronectin. Conclusions/Significance: PLG-binding/activation through the proteins/receptors on the surface of Leptospira could help the bacteria to specifically overcome tissue barriers, facilitating its spread throughout the host.FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo)CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico)Fundacao Butantan, BrazilFAPESP (Brazil

    Apoptose e maturação placentária bovina: um estudo imunohistoquímico e morfométrico

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    Resumo: A liberação da placenta após o parto envolve a perda da adesão materno-fetal e ocorre somente após a maturação completa do placentoma, que está relacionada com a diminuição da celularidade dos tecidos fetal e materno. A apoptose é requerida tanto para a maturação quanto para a liberação normal da placenta após o parto. O objetivo do presente estudo foi avaliar a ocorrência de apoptose em amostras de placenta de vacas em diferentes fases de gestação. Amostras de placentomas de 15 vacas saudáveis com 4 (n=5), 6 (n=5) e 9 (n=5) meses de gestação foram colhidas e processadas rotineiramente para a histologia, imunoistoquímica e histoquímica. As lâminas obtidas foram coradas em HE, Picrosirius Red e submetidas à análise imunoistoquímica das proteínas Caspase 3, Caspase 8, Bax e Bid. O aumento no número de vasos não necessariamente se associou ao aumento do calibre destes durante a evolução da gestação. Os resultados de histomorfometria revelaram aumento da marcação para Bax e Caspases 3 e 8 em células trofoblásticas binucleadas no final da gestação, enquanto o Bid se manteve sem alteração significativa. A histomorfometria das células trofoblásticas mononucleadas revelou expressão alta para Bax no início de gestação, com diminuição aos 6 meses de gestação e aumento das imunomarcações para Caspases 3 e 8, e Bid com o avanço gestacional. Os colágenos tipo I e III não aumentaram do terço médio ao final da gestação, o que é importante para a diminuição da adesão materno-fetal. Esses resultados confirmam que as Caspases 3 e 8, e o Bax estão envolvidos nos mecanismos de ativação da apoptose pela via intrínseca mitocondrial e/ou extrínseca ao longo da gestação em células trofoblásticas binucleadas, e que nas células trofoblásticas mononucleadas o Bax deixa de ser importante, enquanto o Bid e as Caspases 3 e 8 se tornam os mais significativos

    Responsiveness of the Early Childhood Oral Health Impact Scale (ECOHIS) is related to dental treatment complexity

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    Abstract\ud \ud Background\ud The responsiveness of the Early Childhood Oral Health Impact Scale (ECOHIS) has varied greatly across studies; hence, we hypothesized that this discrepancy could be related to the complexity of dental treatment received. Thus, we aimed to evaluate the responsiveness of the ECOHIS to changes in oral health-related quality of life (OHRQoL) following dental treatments of varying complexity in preschool children.\ud \ud \ud Methods\ud Preschool children aged 3 to 6 years were selected; their parents responded to the ECOHIS at baseline. The parents responded to the ECOHIS again and a global transition question 30 days after the children were treated. The type of treatment received by the children was categorized according to complexity, as follows: 1) non-operative treatment only, 2) restorative treatment, and 3) endodontic treatment and/or tooth extraction. Change scores and effect sizes (ES) were calculated for total scores, as well as considering the different treatment types and global transition question responses.\ud \ud \ud Results\ud Of the 152 children who completed the study, the ECOHIS yielded large ES for total scores (0.89). The children showed increasing ES values associated with better perception of improvement, assessed by the global transition question. The magnitude of ES after treatment was related to treatment complexity (0.53, 0.92 and 1.43, for children who received non-operative treatment only, restorative treatment, and endodontic treatment and/or tooth extraction, respectively).\ud \ud \ud Conclusions\ud Parents whose children required more complex dental treatment are more likely to perceive treatment-related changes to OHRQoL assessed with the ECOHIS.The study was funded by Conselho Nacional de Desenvolvimento Científico\ud e Tecnológico – CNPq (Grants # 471817/2012–0 and 306,304/2015–5),\ud Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP (Grant #\ud 2012/24243–7), and Coordenação de Aperfeiçoamento de Pessoal de Nível\ud Superior (CAPES)
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