433 resultados para cloreto de bário
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This paper aimed to study the treatability of rainwater collected in Rio Claro, SP, using natural coagulant tannin based. The tannin was compared with other too primary coagulants, namely ferric chloride and corn starch. Assays were performed in laboratory scale using equipment known as Jarteste and aimed to study the conditions most suitable dosage and coagulation pH. First tests were conducted to compare the coagulating and determination of the conditions to be used in the following tests, taking as a criterion the greatest efficiency for water treatment. Also performed were performed tests to construct the tannin coagulation diagram, using the optimal concentration found in the previous phase, by varying the dosage of coagulant and the pH of clotting in order to determine the isoefficiency regions for apparent color and turbidity. Finally, tests were performed cyclically filtration with filter paper. Preliminary tests indicated that the vegetable tannin concentration 3% (m/m) from the commercial solution was presented the best set of results (84.3% removal of apparent color and 82.51% removal of turbidity) compared to ferric chloride (66.25% removal efficiency and apparent color of turbidity 67.82%) and starch (73.68% removal efficiency apparent color and turbidity to 67.19%). The coagulation diagrams indicate that the best region to work with vegetable tannin 3% is where the coagulant dosage ranges from 15 mg/L to about 37.5 mg/L and coagulation pH ranging from about 6.5 to 7.5. The cyclic filtration showed to be not efficient for the best dosage of coagulant, due to the process of clogging of the filter paper, but proved to be efficient for other dosages. Thus, for the waters studied, the results indicate that the natural coagulant based tannin is an alternative to conventional coagulants, possessing benefits of technical and environmental
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Apocynin, a methoxy-catechol originally extracted from the root of Picrorhiza kurroa, has been used as an inhibitor of the NADPH oxidase complex in phagocytic and nonphagocytic cells. Its mechanism of inhibition is linked to their prior activation through the action of peroxidases leading to oxidation of the dimeric product, diapocynin. In this study, dipocinina was synthesized and investigated its effect as an inhibitor of activation NADPH oxidase in neutrophils (PMN) and peripheral blood mononuclear cells (PBMC). The synthesis of diapocinina was performed by oxidation of apocinina by potassium persulphate in the midst of water for 5 minutes at room temperature. The precipitate was filtered and washed with water and methanol. Diapocinina was characterized by mass spectrometry. PMN and PBMC were obtained from peripheral blood of healthy donors and purified for gelatin sedimentation, or centrifugation with Histopaque ®, the red cells were lysed with ice water or ammonium chloride. Diapocinina or apocinina were incubated with opsonized zymosan, activation of PMNs and release of superoxide anion, these monitored by chemiluminescent assay dependent lucigenina. We found that diapocinina inhibitor was no better than the apocinina in PMN. However, diapocinina was more efficient than apocinina as an inhibitor of NADPH oxidase in PBMC. In conclusion, whereas PBMC are relatively poor compared with peroxidases PMN, our results are consistent with the need for oxidation apocinina for its effect as an inhibitor of NADPH oxidase
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A psoríase é uma doença inflamatória crônica da pele caracterizada pela hiperproliferação dos queratinócitos. Apesar de não se conhecer a causa da doença, sabe-se que ela envolve uma série de alterações no sistema imune inato e adquirido, principalmente. Entre essas alterações estão o aumento da produção de citocinas pró-inflamatórias como a interleucina 1 e o fator de necrose tumoral α (TNF- α). O metotrexato é um antinéoplásico análogo do ácido fólico, mas que tem seu uso consolidado no tratamento da psoríase. Sua ação principal está na inibição indireta de células em crescimento exponencial, como células tumorais e em proliferação. A modulação dos níveis de TNF-α vem a ser uma boa alternativa para o controle da psoríase. A talidomida foi o primeiro fármaco que desempenhava tal atividade, mas devido a sua teratogenicidade deixou de ser utilizada. Descobriu-se que a função antiinflamatória estava relacionada à parte ftalimídica da molécula. Então, a partir daí passou-se a sintetizar derivados que pudessem ter a mesma atividade, porém com toxicidade reduzida. Esse trabalho visa a síntese de um pró-fármaco recíproco, com a finalidade de uso tópico, unindo as atividades antiinflamatórias e antiproliferativa do metotrexato e imunomoduladora do derivado ftalimídico, o cloreto de 4-(1,3-dioxo-1,3-diidro-2H-isoindol-2-il)benzenosulfonil, para a redução de efeitos adversos e toxicidade decorrente do tratamento, visando a melhora da qualidade de vida do paciente
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Apocynin has been used as an efficient inhibitor of the multi-enzymatic complex NADPH oxidase in many experimental models involving phagocytic and nonphagocytic cells. The mechanism of inhibition has been linked with the previous activation of apocynin through the action of cellular peroxidases leading to the formation of a dimeric oxidation product, diapocynin. In this study we compared apocynin with pure diapocynin regarding their effects as scavenger of hydrogen peroxide and hypochlorous generated by glucose/glucose oxidase and myeloperoxidase respectively, and as inhibitors of the production of hydrogen peroxide and hypochlorous acid by activated neutrophils. The production of hydrogen peroxide was measured by the oxidation of the fluorescent substance Amplex Red and the production of hypochlorous acid by was measured as taurine-chloramine derivative using the chromogenic substrate 3,3’,5,5’- tetramethylbenzidine (TMB). Neutrophils (1 x106 cells/mL) were pre-incubated in PBS buffer supplemented with 1 mM calcium chloride, 0.5 mM magnesium chloride, 1 mg/mL glucose and 5 mM taurine in the presence or absence of inhibitors. The reactions were triggered by adding the soluble stimulus Forbol Miristate Acetate PMA or zymosan and incubated by additional 30 minutes. We found that pure diapocynin was not better than apocynin regarding its scavenger and inhibitory properties. These results suggest that the formation of diapocynin is not essential for the action of apocynin as inhibitor of NADPH oxidase activation
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Concerns about the quality of groundwater have been continuously rising, considering its importance for the public water supply in the State of São Paulo, and even more due to the impact that anthropic action has been causing to the original quality of that natural resource. It is extremely relevant to identify the contamination focuses along the aquifers of the State of São Paulo. This report aims to evaluate nitrates and fluorides concentrations along the aquifers present in the state, in order to identify places where change in the quality of groundwater is observed, through the comparison between measured concentrations and reference values, such as: “Intervention Value” (maximum allowed value) and “Alert Value” (attention required value). To perform this research, a full compilation and organization has been done on chemical analysis data from the “Sistema de Informações de Águas Subterrâneas - SIDAS”, made available by the “Divisão de Procedimentos de Outorga – DPO” of the “Departamento de Água e Energia Elétrica – DAEE”. This work has made possible the build-up of a database composed by 6,860 wells, with analytical data ready to be interpreted, containing information about water pH, electrical conductivity, hardness and chloride, iron, fluoride, nitrogen, nitrates and total dissolved solids concentrations. This database shows concentration data for nitrates (6,157 wells) and fluoride (3,316 wells). From this information, maps for nitrates and fluorides concentration distributions have been made, by each aquifer and each “Unidade de Gerenciamento de Recursos Hídricos – UGRHI”, which has enabled the identification of wells where the concentrations of these chemical compounds exceeds the reference values. Concerning nitrates, these analysis indicated the existence of contamination sources from rural and urban zones, mostly present in the west region... (Complete abstract click electronic access below)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Agronomia (Produção Vegetal) - FCAV
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Pós-graduação em Agronomia (Agricultura) - FCA
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Métodos comparativos foram desenvolvidos para detectar e quantificar o corante solvente azul 14 (SA-14) em amostras de combustíveis. O método eletroanalítico foi baseado na técnica de voltametria de onda quadrada (VOQ) com detecção em +0,60 V vs. Ag/AgCl sobre o eletrodo de carbono vítreo, usando tampão Britton-Robinson e N, N-dimetilformamida (1:1, v/v) como eletrólito suporte. Para metodologia, envolvendo a cromatografia líquida de alta performance (CLAE) foi empregada uma fase móvel composta de acetonitrila e cloreto de lítio (85:15, v/v) e a detecção eletroquímica foi realizada em um potencial de oxidação em +0,65 V vs. Ag/AgCl. Sob as melhores condições de trabalho curvas de calibração foram obtidas, para ambos os métodos, as quais foram lineares na faixa de concentração de 5,0×10 -7 a 6,0×10 -6 mol L-1 (VOQ) e 8,0×10 -8 a 3,0×10 -6 mol L-1 (CLAE). Os métodos foram aplicados para quantificar o corante em amostras de álcool e querosene após um simples processo de extração em fase sólida com resultados de recuperação satisfatórios.
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Pós-graduação em Química - IQ
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Pós-graduação em Química - IQ
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The knowledge of the etiology of any disease or condition is paramount to a safe and effective treatment. This literature review aims to show some options to treat dentine hypersensitivity (HSDC). The loss of cervical enamel and cementum exposure of tubules leads to a painful condition and patient discomfort, called HSDC. This loss of tooth structure occurs due to formation of cervical lesions in cases of gingival recession, abrasion, erosion, or abfraction by the association of two or more factors. Some treatments are not effective, but there are effective therapies, such as: application of ferric oxalate, potassium oxalate, potassium nitrate, fluoride varnish, solutions of calcium phosphate, adhesives and Bonding procedures. Therefore, the identification and removal of etiological factors is essential to successful treatment of HSDC normally associated to tubules obliterate and consequent reduction of fluid motion within the dentin.
Análise físico-química do MTA e do cimento Portland associado a quatro diferentes radiopacificadores
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Química - IQ