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listelement.badge.dso-type Item , Using rodogram function to characterize hurst coefficient in rock profiles([PENDENTE_COMPLETUDE_DSPACE], 2018) David Alvarenga DrumondA rugosidade é uma característica fundamental para definir a deformabilidade e a resistência das rochas. Uma caracterização detalhada da geometria da superfície das descontinuidades é essencial para compreender alguns dos comportamentos mecânicos da rocha. A geometria fractal tem sido utilizada por diversos autores para correlacionar parâmetros como o coeficiente de Hurst com o JRC (coeficiente de rugosidade das juntas), a fim de descrever melhor a geometria da superfície. Perfis de superfície podem ser caracterizados por uma dimensão fractal que representa a recorrência geométrica em pequena escala. Neste artigo, propomos modificar a metodologia utilizada para identificar o coeficiente de Hurst, incorporando a função rodograma na análise do JRC. A função proposta é menos influenciada por efeitos de deriva e parece ser mais precisa do que a função variograma comumente utilizada. Modelos matemáticos robustos de continuidade espacial podem ser uma alternativa melhor para caracterizar a rugosidade das descontinuidades rochosas.listelement.badge.dso-type Item , Rocha contendo biotita como fonte alternativa de potássio para fertilizante após processamento térmico com aditivos([PENDENTE_COMPLETUDE_DSPACE], 2019) Antônio Clareti PereiraBiotite is a ferromagnesian phyllosilicate that contains potassium. It is very abundant and scattered all over the world. Usually formed as a secondary product in metamorphic processes, it is considered to be an impurity in many mineral processing. Even though it is an alternative source of potassium, it is still not extracted commercially on a large scale due to the lack of commercial technology that makes the business viable economically. The objective of this work was to investigate the effect of thermalprocessing, using additives, in the solubilization of potassium and impurities in dilute mineral acid, of rock contains biotite. A rock from the Carajás-Pará-Brazil mineral province, with a content of 9.7% K₂O and 70% biotite was selected. Thermal processing was performed at two temperatures, 800°C and 900°C, for 6h using two systems: (biotite + CaCO₃+ MgCl2.6H2O) and (biotite + gypsum + Na₂CO₃). The sulfuric acid leaching step was performed at pH maintained between 2.0 and 3.0, at 85 °Cfor 1h. The extraction in the system with magnesium chloride (800°C) reached 63% of the potassium and with solubilization maximum of 5% of Fe and Al. The extractions of potassium with gypsum were.listelement.badge.dso-type Item , Converging TLR9 and PI3Kgamma signaling induces sterile inflammation and organ damage(Universidade Federal de Minas Gerais, 2019) Bráulio Henrique Freire Lima; Pedro Elias Marques; Lindisley Ferreira Gomides; Matheus Silvério Mattos; Lucas Kraemer; Celso Martins Queiroz-Junior; Mark Lennon; Emilio Hirsch; Remo Castro Russo; Gustavo Batista Menezes; Edith Hessel; Augustin Amour; Mauro Martins TeixeiraToll-like receptor 9 (TLR9) and Phosphatidylinositol-3-kinase gamma (PI3Kγ) are very important effectors of the immune response, however, the importance of such crosstalk for disease development is still a matter of discussion. Here we show that PI3Kγ is required for immune responses in which TLR9 is a relevant trigger. We demonstrate the requirement of PI3Kγ for TLR9-induced inflammation in a model of CpG-induced pleurisy. Such requirement was further observed in inflammatory models where DNA sensing via TLR9 contributes to disease, such as silicosis and drug-induced liver injury. Using adoptive transfer, we demonstrate that PI3Kγ is important not only in leukocytes but also in parenchymal cells for the progression of inflammation. We demonstrate this crosstalk between TLR9 and PI3Kγ in vitro using human PBMCs. The inhibition of PI3Kγ in CpG-stimulated PBMCs resulted in reduction of both cytokine production and phosphorylated Akt. Therefore, drugs that target PI3Kγ have the potential to treat diseases mediated by excessive TLR9 signalling.listelement.badge.dso-type Item , ROCK Inhibition Drives Resolution of Acute Inflammation by Enhancing Neutrophil Apoptosis(Universidade Federal de Minas Gerais, 2019) Izabela Galvão; Rayssa Maciel Athayde; Denise Alves Perez; Alesandra Corte Reis; Luísa Rezende; Vivian Louise Soares de Oliveira; Barbara Maximino Rezende; William Antônio Gonçalves; Lirlândia Pires de Sousa; Mauro Martins Teixeira; Vanessa PinhoUncontrolled inflammation leads to tissue damage and it is central for the development of chronic inflammatory diseases and autoimmunity. An acute inflammatory response is finely regulated by the action of anti-inflammatory and pro-resolutive mediators, culminating in the resolution of inflammation and restoration of homeostasis. There are few studies investigating intracellular signaling pathways associated with the resolution of inflammation. Here, we investigate the role of Rho-associated kinase (ROCK), a serine/threonine kinase, in a model of self-resolving neutrophilic inflammatory. We show that ROCK activity, evaluated by P-MYPT-1 kinetics, was higher during the peak of lipopolysaccharide-induced neutrophil influx in the pleural cavity of mice. ROCK inhibition by treatment with Y-27632 decreased the accumulation of neutrophils in the pleural cavity and was associated with an increase in apoptotic events and efferocytosis, as evaluated by an in vivo assay. In a model of gout, treatment with Y-27632 reduced neutrophil accumulation, IL-1β levels and hypernociception in the joint. These were associated with reduced MYPT and IκBα phosphorylation levels and increased apoptosis. Finally, inhibition of ROCK activity also induced apoptosis in human neutrophils and destabilized cytoskeleton, extending the observed effects to human cells. Taken together, these data show that inhibition of the ROCK pathway might represent a potential therapeutic target for neutrophilic inflammatory diseases.listelement.badge.dso-type Item , Yellow fever virus is susceptible to sofosbuvir both in vitro and in vivo(Universidade Federal de Minas Gerais, 2019) Caroline Souza de Freitas; Luiza Mendonça Higa; Carolina de Queiroz Sacramento; André Costa Ferreira; Patrícia Alves Reis; Rodrigo Delvecchio; Fabio Luís Lima Monteiro; Giselle Barbosa Lima; Harrison James Westgarth; Yasmine Rangel Vieira; Mayara Mattos; Natasha Rocha; Lucas Villas Bôas Hoelz; Rennan Papaleo Paes Leme; Mônica Macedo Bastos; Gisele Olinto Libanio Rodrigues; Carla Elizabeth Lopes; Celso Martins Queiroz Junior; Cristiano Xavier Lima; Vivian Vasconcelos Costa; Mauro Martins Teixeira; Fernando Augusto Bozza; Patrícia Torres Bozza; Núbia Boechat; Amílcar Tanuri; Thiago Moreno Lopes e SouzaYellow fever virus (YFV) is a member of the Flaviviridae family. In Brazil, yellow fever (YF) cases have increased dramatically in sylvatic areas neighboring urban zones in the last few years. Because of the high lethality rates associated with infection and absence of any antiviral treatments, it is essential to identify therapeutic options to respond to YFV outbreaks. Repurposing of clinically approved drugs represents the fastest alternative to discover antivirals for public health emergencies. Other Flaviviruses, such as Zika (ZIKV) and dengue (DENV) viruses, are susceptible to sofosbuvir, a clinically approved drug against hepatitis C virus (HCV). Our data showed that sofosbuvir docks onto YFV RNA polymerase using conserved amino acid residues for nucleotide binding. This drug inhibited the replication of both vaccine and wild-type strains of YFV on human hepatoma cells, with EC50 values around 5 μM. Sofosbuvir protected YFV-infected neonatal Swiss mice and adult type I interferon receptor knockout mice (A129-/-) from mortality and weight loss. Because of its safety profile in humans and significant antiviral effects in vitro and in mice, Sofosbuvir may represent a novel therapeutic option for the treatment of YF.