55 research outputs found

    LPS-induced IL-8 activation in human intestinal epithelial cells is accompanied by specific histone H3 acetylation and methylation changes

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    <p>Abstract</p> <p>Background</p> <p>The release of LPS by bacteria stimulates both immune and specific epithelial cell types to release inflammatory mediators. It is known that LPS induces the release of IL-8 by intestinal mucosal cells. Because it is now emerging that bacteria may induce alteration of epigenetic patterns in host cells, we have investigated whether LPS-induced IL-8 activation in human intestinal epithelial cells involves changes of histone modifications and/or DNA methylation at IL-8 gene regulatory region.</p> <p>Results</p> <p>RT-PCR analysis showed that IL-8 mRNA levels rapidly increase after exposure of HT-29 cells to LPS. DNA demethylating agents had no effects on IL-8 expression, suggesting that DNA methylation was not involved in IL-8 gene regulation. Consistently we found that 5 CpG sites located around IL-8 transcription start site (-83, -7, +73, +119, +191) were unmethylated on both lower and upper strand either in LPS treated or in untreated HT-29 cells, as well as in normal intestinal mucosa.</p> <p>Conversely, pretreatment of HT-29 cells with deacetylase inhibitors strengthened the LPS-mediated IL-8 activation. Inhibitors of histone deacetylases could induce IL-8 mRNA expression also in the absence of LPS, suggesting that chromatin modifications could be involved in IL-8 gene regulation. Chromatin immunoprecipitation analyses showed that, concurrently with IL-8 activation, transient specific changes in H3 acetylation and H3K4, H3K9 and H3K27 methylation occurred at IL-8 gene promoter during LPS stimulation. Changes of H3-acetyl, H3K4me2 and H3K9me2 levels occurred early, transiently and corresponded to transcriptional activity, while changes of H3K27me3 levels at IL-8 gene occurred later and were long lasting.</p> <p>Conclusion</p> <p>The results showed that specific chromatin modifications occurring at IL-8 gene, including histone H3 acetylation and methylation, mark LPS-mediated IL-8 activation in intestinal epithelial cells while it is unlikely that DNA methylation of IL-8 promoter is directly involved in IL-8 gene regulation in these cells.</p

    Chromatin and DNA methylation dynamics during retinoic acid-induced RET gene transcriptional activation in neuroblastoma cells.

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    Although it is well known that RET gene is strongly activated by retinoic acid (RA) in neuroblastoma cells, the mechanisms underlying such activation are still poorly understood. Here we show that a complex series of molecular events, that include modifications of both chromatin and DNA methylation state, accompany RA-mediated RET activation. Our results indicate that the primary epigenetic determinants of RA-induced RET activation differ between enhancer and promoter regions. At promoter region, the main mark of RET activation was the increase of H3K4me3 levels while no significant changes of the methylation state of H3K27 and H3K9 were observed. At RET enhancer region a bipartite chromatin domain was detected in unstimulated cells and a prompt demethylation of H3K27me3 marked RET gene activation upon RA exposure. Moreover, ChIP experiments demonstrated that EZH2 and MeCP2 repressor complexes were associated to the heavily methylated enhancer region in the absence of RA while both complexes were displaced during RA stimulation. Finally, our data show that a demethylation of a specific CpG site at the enhancer region could favor the displacement of MeCP2 from the heavily methylated RET enhancer region providing a novel potential mechanism for transcriptional regulation of methylated RA-regulated loci

    Isogeometric analysis for fluid shear stress in cancer cells

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    Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2018 do Instituto Politécnico de Lisboa. Código de referência IPL/2018/IGACFC_ISELThe microenvironment of the tumor is a key factor regulating tumor cell invasion and metastasis. The effects of physical factors in tumorigenesis is unclear. Shear stress, induced by liquid flow, plays a key role in proliferation, apoptosis, invasion, and metastasis of tumor cells. The mathematical models have the potential to elucidate the metastatic behavior of the cells’ membrane exposed to these microenvironment forces. Due to the shape configuration of the cancer cells, Non-uniform Rational B-splines (NURBS) lines are very adequate to define its geometric model. The Isogeometric Analysis allows a simplified transition of exact CAD models into the analysis avoiding the geometrical discontinuities of the traditional Galerkin traditional techniques. In this work, we use an isogeometric analysis to model the fluid-generated forces that tumor cells are exposed to in the vascular and tumor microenvironments, in the metastatic process. Using information provided by experimental tests in vitro, we present a suite of numerical experiments which indicate, for standard configurations, the metastatic behavior of cells exposed to such forces. The focus of this paper is strictly on geometrical sensitivities to the shear stress’ exhibition for the cell membrane, this being its innovation.info:eu-repo/semantics/publishedVersio

    Guidelines for the management and treatment of periodic fever syndromes Cryopyrin-associated periodic syndromes (cryopyrinopathies – CAPS)

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    AbstractObjectiveTo establish guidelines based on cientific evidences for the management of cryopyrin associated periodic syndromes.Description of the evidence collection methodThe Guideline was prepared from 4 clinical questions that were structured through PICO (Patient, Intervention or indicator, Comparison and Outcome), to search in key primary scientific information databases. After defining the potential studies to support the recommendations, these were graduated considering their strength of evidence and grade of recommendation.Results1215 articles were retrieved and evaluated by title and abstract; from these, 42 articles were selected to support the recommendations.Recommendations1. The diagnosis of CAPS is based on clinical history and clinical manifestations, and later confirmed by genetic study. CAPS may manifest itself in three phenotypes: FCAS (mild form), MWS (intermediate form) and CINCA (severe form). Neurological, ophthalmic, otorhinolaryngological and radiological assessments may be highly valuable in distinguishing between syndromes; 2. The genetic diagnosis with NLRP3 gene analysis must be conducted in suspected cases of CAPS, i.e., individuals presenting before 20 years of age, recurrent episodes of inflammation expressed by a mild fever and urticaria; 3. Laboratory abnormalities include leukocytosis and elevated serum levels of inflammatory proteins; and 4. Targeted therapies directed against interleukin-1 lead to rapid remission of symptoms in most patients. However, there are important limitations on the long-term safety. None of the three anti-IL-1β inhibitors prevents progression of bone lesions

    Profile of paediatric rheumatology specialists and services in the state of São Paulo

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    INTRODUCTION: Paediatric rheumatology (PR) is an emerging specialty, practised by a limited number of specialists. Currently, there is neither a record of the profile of rheumatology patients being treated in Brazil nor data on the training of qualified rheumatology professionals in the country. OBJECTIVE: To investigate the profile of PR specialists and services, as well as the characteristics of paediatric patients with rheumatic diseases, for estimating the current state of rheumatology in the state of São Paulo. PATIENTS AND METHODS: In 2010, the scientific department of PR of the Paediatric Society of São Paulo administered a questionnaire that was answered by 24/31 accredited specialists in PR practising in state of São Paulo and by 8/21 institutions that provide PR care. RESULTS: Most (91%) of the surveyed professionals practise in public institutions. Private clinics (28.6%) and public institutions (37.5%) reported not having access to nailfold capillaroscopy, and 50% of the private clinics reported not having access to acupuncture. The average duration of professional practise in PR was 9.4 years, and 67% of the physicians had attended postgraduate programmes. Seven (87.5%) public institutions perform teaching activities, in which new paediatric rheumatologists are trained, and five (62.5%) offer postgraduate programmes. Two-thirds of the surveyed specialists use immunosuppressants and biological agents classified as restricted use by the Health Secretariat. The disease most frequently reported was juvenile idiopathic arthritis (29.1-34.5%), followed by juvenile systemic lupus erythematosus (JSLE) (11.6-12.3%) and rheumatic fever (9.1-15.9%). The incidence of vasculitis (including Henoch-Schönlein purpura, Wegener's granulomatosis, and Takayasu's arteritis) and autoinflammatory syndromes was higher in public institutions compared to other institutions (P = 0.03, P = 0.04, P = 0.002, and P < 0.0001, respectively). Patients with JSLE had the highest mortality rate (68% of deaths), mainly due to infection. CONCLUSION: The field of PR in the state of São Paulo has a significant number of specialists with postgraduate degrees who mostly practise at teaching institutions with infrastructures appropriate for the care of high-complexity patients.INTRODUÇÃO: A reumatologia pediátrica (RP) é uma especialidade emergente, com número restrito de especialistas, e ainda não conta com uma casuística brasileira sobre o perfil dos pacientes atendidos e as informações sobre a formação de profissionais capacitados. OBJETIVO: Estudar o perfil dos especialistas e dos serviços em RP e as características dos pacientes com doenças reumáticas nessa faixa etária a fim de estimar a situação atual no estado de São Paulo (ESP). PACIENTES E MÉTODOS: No ano de 2010 o departamento científico de RP da Sociedade de Pediatria de São Paulo encaminhou um questionário respondido por 24/31 especialistas com título de especialização em RP que atuam no ESP e por 8/12 instituições com atendimento nesta especialidade. RESULTADOS: A maioria (91%) dos profissionais exerce suas atividades em instituições públicas. Clínicas privadas (28,6%) e instituições (37,5%) relataram não ter acesso ao exame de capilaroscopia e 50% das clínicas privadas não tem acesso à acupuntura. A média de tempo de prática profissional na especialidade foi de 9,4 anos, sendo 67% deles pós-graduados. Sete (87,5%) instituições públicas atuam na área de ensino, formando novos reumatologistas pediátricos. Cinco (62,5%) delas têm pós-graduação. Dois terços dos especialistas utilizam imunossupressores e agentes biológicos de uso restrito pela Secretaria da Saúde. A doença mais atendida foi artrite idiopática juvenil (29,1%-34,5%), seguida de lúpus eritematoso sistêmico juvenil (LESJ) (11,6%-12,3%) e febre reumática (9,1%-15,9%). Vasculites (púrpura de Henoch Schönlein, Wegener, Takayasu) e síndromes autoinflamatórias foram mais incidentes nas instituições públicas (P = 0,03; P = 0,04; P = 0,002 e P < 0,0001, respectivamente). O LESJ foi a doença com maior mortalidade (68% dos óbitos), principalmente por infecção. CONCLUSÃO: A RP no ESP conta com um número expressivo de especialistas pós-graduados, que atuam especialmente em instituições de ensino, com infraestrutura adequada ao atendimento de pacientes de alta complexidade.Universidade Federal de São Paulo (UNIFESP) Departamento de Pediatria Setor de Reumatologia PediátricaUniversidade de São Paulo Faculdade de Medicina Hospital das ClínicasSanta Casa de Misericórdia de São Paulo Departamento de Pediatria Setor de ReumatologiaUniversidade Estadual de Campinas Unidade de Reumatologia PediátricaUniversidade de São Paulo Faculdade de Medicina de Ribeirão Preto Departamento de Puericultura e PediatriaSanta Casa de Misericórdia de Santos Setor de Reumatologia PediátricaFaculdade de Medicina de Botucatu Hospital Estadual de Bauru Serviço de Reumatologia PediátricaFaculdade de Medicina de BotucatuUNIFESP, Depto. de Pediatria Setor de Reumatologia PediátricaSciEL

    Brazilian multicenter study of 71 patients with juvenile-onset Takayasu's arteritis: clinical and angiographic features

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    Objective: To describe the clinical and angiographic characteristics of Takayasu's arteritis in Brazilian children and adolescents. Methods: A retrospective data collection was performed in 71 children and adolescents followed in 10 Brazilian reference centers in Pediatric Rheumatology. The evaluation was carried out in three different time points: from onset of symptoms to diagnosis, from the 6th to 12th month of diagnosis, and in the last visit. Results: Of 71 selected patients, 51 (71.8%) were girls. The mean age of onset of symptoms and of time to diagnosis was 9.2 (+/- 4.2) years and 1.2 (+/- 1.4) years, respectively. At the end of the study, 20 patients were in a state of disease activity, 39 in remission and 5 had evolved to death. The most common symptoms in baseline assessment, second evaluation, and final evaluation were, respectively: constitutional, musculoskeletal, and neurological symptoms. A decrease in peripheral pulses was the most frequent cardiovascular signal, and an increase in erythrocyte sedimentation rate was the most frequent laboratory finding in all three evaluation periods. The tuberculin test was positive in 41% of those tested. Stenosis was the most frequent angiographic lesion, abdominal artery was the most affected segment, and angiographic type IV the most frequent. Most (90%) participants were treated with glucocorticoids, 85.9% required another immunosuppressive drug, and 29.6% underwent angioplasty. Conclusion: This is the largest study on juvenile-onset Takayasu arteritis, and a high number of patients under the age of 10 years, with predominance of constitutional symptoms early in the disease, was observed. (C) 2016 Elsevier Editora Ltda. All rights reserved.Univ Fed Sao Paulo, Dept Pediat, Sect Pediat Rheumatol, Sao Paulo, SP, BrazilUniv Sao Paulo, Inst Crianca, Pediat Rheumatol Sect, Sao Paulo, SP, BrazilSanta Casa Misericordia Sao Paulo, Sao Paulo, SP, BrazilUniv Sao Paulo, Sch Med, Ribeirao Preto, SP, BrazilUniv Estado Rio de Janeiro, BR-20550011 Rio De Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, Inst Pediat Martagao Gesteira, Rio De Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, Rheumatol Unit, Rio De Janeiro, RJ, BrazilUniv Fed Pernambuco, Rheumatol Unit, Recife, PE, BrazilUniv Fed Bahia, Salvador, BA, BrazilHosp Pequeno Principe, Curitiba, Parana, BrazilUniv Fed Sao Paulo, Dept Pediat, Sect Pediat Rheumatol, Sao Paulo, SP, BrazilWeb of Scienc

    Profile of paediatric rheumatology specialists and services in the state of São Paulo

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    INTRODUCTION: Paediatric rheumatology (PR) is an emerging specialty, practised by a limited number of specialists. Currently, there is neither a record of the profile of rheumatology patients being treated in Brazil nor data on the training of qualified rheumatology professionals in the country. OBJECTIVE: To investigate the profile of PR specialists and services, as well as the characteristics of paediatric patients with rheumatic diseases, for estimating the current state of rheumatology in the state of São Paulo. PATIENTS AND METHODS: In 2010, the scientific department of PR of the Paediatric Society of São Paulo administered a questionnaire that was answered by 24/31 accredited specialists in PR practising in state of São Paulo and by 8/21 institutions that provide PR care. RESULTS: Most (91%) of the surveyed professionals practise in public institutions. Private clinics (28.6%) and public institutions (37.5%) reported not having access to nailfold capillaroscopy, and 50% of the private clinics reported not having access to acupuncture. The average duration of professional practise in PR was 9.4 years, and 67% of the physicians had attended postgraduate programmes. Seven (87.5%) public institutions perform teaching activities, in which new paediatric rheumatologists are trained, and five (62.5%) offer postgraduate programmes. Two-thirds of the surveyed specialists use immunosuppressants and biological agents classified as restricted use by the Health Secretariat. The disease most frequently reported was juvenile idiopathic arthritis (29.1-34.5%), followed by juvenile systemic lupus erythematosus (JSLE) (11.6-12.3%) and rheumatic fever (9.1-15.9%). The incidence of vasculitis (including Henoch-Schönlein purpura, Wegener's granulomatosis, and Takayasu's arteritis) and autoinflammatory syndromes was higher in public institutions compared to other institutions (P = 0.03, P = 0.04, P = 0.002, and P < 0.0001, respectively). Patients with JSLE had the highest mortality rate (68% of deaths), mainly due to infection. CONCLUSION: The field of PR in the state of São Paulo has a significant number of specialists with postgraduate degrees who mostly practise at teaching institutions with infrastructures appropriate for the care of high-complexity patients.INTRODUÇÃO: A reumatologia pediátrica (RP) é uma especialidade emergente, com número restrito de especialistas, e ainda não conta com uma casuística brasileira sobre o perfil dos pacientes atendidos e as informações sobre a formação de profissionais capacitados. OBJETIVO: Estudar o perfil dos especialistas e dos serviços em RP e as características dos pacientes com doenças reumáticas nessa faixa etária a fim de estimar a situação atual no estado de São Paulo (ESP). PACIENTES E MÉTODOS: No ano de 2010 o departamento científico de RP da Sociedade de Pediatria de São Paulo encaminhou um questionário respondido por 24/31 especialistas com título de especialização em RP que atuam no ESP e por 8/12 instituições com atendimento nesta especialidade. RESULTADOS: A maioria (91%) dos profissionais exerce suas atividades em instituições públicas. Clínicas privadas (28,6%) e instituições (37,5%) relataram não ter acesso ao exame de capilaroscopia e 50% das clínicas privadas não tem acesso à acupuntura. A média de tempo de prática profissional na especialidade foi de 9,4 anos, sendo 67% deles pós-graduados. Sete (87,5%) instituições públicas atuam na área de ensino, formando novos reumatologistas pediátricos. Cinco (62,5%) delas têm pós-graduação. Dois terços dos especialistas utilizam imunossupressores e agentes biológicos de uso restrito pela Secretaria da Saúde. A doença mais atendida foi artrite idiopática juvenil (29,1%-34,5%), seguida de lúpus eritematoso sistêmico juvenil (LESJ) (11,6%-12,3%) e febre reumática (9,1%-15,9%). Vasculites (púrpura de Henoch Schönlein, Wegener, Takayasu) e síndromes autoinflamatórias foram mais incidentes nas instituições públicas (P = 0,03; P = 0,04; P = 0,002 e P < 0,0001, respectivamente). O LESJ foi a doença com maior mortalidade (68% dos óbitos), principalmente por infecção. CONCLUSÃO: A RP no ESP conta com um número expressivo de especialistas pós-graduados, que atuam especialmente em instituições de ensino, com infraestrutura adequada ao atendimento de pacientes de alta complexidade.34635

    IDENTIFICATION OF A GDP-MANNOSE PYROPHOSPHORYLASE GENE FROM SULFOLOBUS SOLFATARICUS.

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    An open reading frame (ORF) encoding a putative GDP-mannose pyrophosphorylase (SsoGMPP) was identified on the genome sequence of Sulfolobus solfataricus P2, the predicted gene product showing high amino acid sequence homology to several archaeal, bacterial, and eukaryal GDP-mannose pyrophosphorylases such as guanidine diphosphomannose pyrophosphorylases (GMPPs) from Saccharomyces cerevisiae and Arabidopsis thaliana. The sequence was PCR amplified from genomic DNA of S. solfataricus P2 and heterologous gene expression obtained as a fusion to glutathione S-transferase in Escherichia coli, under conditions suitable to reduce the formation of inclusion bodies. Specific assays performed at 60 jC revealed the presence of the archaeal synthesizing GDP-mannose enzyme activity in the cell extracts of the transformed E. coli. As a positive control, the same assays were performed at the mesophilic enzyme optimum temperature on the already characterized yeast recombinant GMPP. The recombinant protein was purified to homogeneity by glutathione sepharose affinity chromatography and its thermophilic nature could be verified. The enzyme was definitively identified by demonstrating its capability to catalyze also the reverse reaction of pyrophosphorolysis and, most interestingly, its high specificity for synthesizing GDP-mannose
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