A representação do afro-descendente brasileiro na narrativa ficcional

Módulo 5

Efeito de glucanas do fungo Caripia montagnei em modelo de inflamação intestinal induzida por tnbs em ratos Wistar e em células de carcinoma de cólon humano HT-29

Compounds derived from fungi has been the subject of many studies in order to broaden the knowledge of their bioactive potential. Polysaccharides from Caripia montagnei have been described to possess anti-inflammatory and antioxidant properties. In this study, glucans extracted from Caripia montagnei mushroom were chemically characterized and their effects evaluated at different doses and intervals of treatment. It was also described their action on colonic injury in the model of colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS), and its action on cells of the human colon carcinoma (HT-29). Compounds extracted of C. montagnei contain high level of carbohydrates (96%), low content of phenolic compounds (1.5%) and low contamination with proteins (2.5%). The (FT-IR) and (NMR) analysis showed that polysaccharides from this species of mushroom are composed of α- and β-glucans. The colonic damage was evaluated by macroscopic, histological, biochemical and immunologic analyses. The results showed a reduction of colonic lesions in all groups treated with the glucans of Caripia montagnei (GCM). GCM significantly reduced the levels of IL-6 (50 and 75 mg/kg, p < 0.05), a major inflammatory cytokine. Biochemical analyses showed that such glucans acted on reducing levels of alkaline phosphatase (75 mg/kg, p < 0.01), nitric oxide (p < 0.001), and myeloperoxidase (p < 0.001). These results were confirmed microscopically by the reduction of cellular infiltration. The increase of catalase activity suggest a protective effect of GCM on colonic tissue, confirming their anti-inflammatory potential. GCM displayed cytostatic activity against HT-29 cells, causing accumulation of cells in G1 phase, blocking the cycle cell progression. Those glucans also showed ability to modulate the adhesion of HT-29 cells to Matrigel® and reduced the oxidative stress. The antiproliferative activity against HT-29 cells displayed by GCM (p <0.001) can be attributed to its cytostatic activity and induction of apoptosis by GCM

Desenvolvimento de uma formulação cólon específica visando o tratamento da colite ulcerativa

Micro and nanoparticulate systems as drug delivery carriers have achieved successful therapeutic use by enhancing efficacy and reducing toxicity of potent drugs. The improvement of pharmaceutical grade polymers has allowed the development of such therapeutic systems. Microencapsulation is a process in which very thin coatings of inert natural or synthetic polymeric materials are deposited around microsized particles of solids or around droplets. Products thus formed are known as microparticles. Xylan is a natural polymer abundantly found in nature. It is the most common hemicellulose, representing more than 60% of the polysaccharides existing in the cell walls of corn cobs, and is normally degraded by the bacterial enzymes present in the colon of the human body. Therefore, this polymer is an eligible material to produce colon-specific drug carriers. The aim of this study was to evaluate the technological potential of xylan for the development of colon delivery systems for the treatment of inflammatory bowel diseases. First, coacervation was evaluated as a feasible method to produce xylan microcapsules. Afterwards, interfacial cross-linking polymerization was studied as a method to produce microcapsules with hydrophilic core. Additionally, magnetic xylan-coated microcapsules were prepared in order to investigate the ability of producing gastroresistant systems. Besides, the influence of the external phase composition on the production and mean diameter of microcapsules produced by interfacial cross-linking polymerization was investigated. Also, technological properties of xylan were determined in order to predict its possible application in other pharmaceutical dosage forms

Micropartículas poliméricas à base de xilana e Eudragit® S-100 contendo mesalazina visando à liberação cólon-específica

Colon-specific drug delivery systems have attracted increasing attention from the pharmaceutical industry due to their ability of treating intestinal bowel diseases (IBD), which represent a public health problem in several countries. In spite of being considered a quite effective molecule for the treatment of IBD, mesalazine (5-ASA) is rapidly absorbed in the upper gastrointestinal tract and its systemic absorption leads to risks of adverse effects. The aim of this work was to develop a microparticulate system based on xylan and Eudragit® S- 100 (ES100) for colon-specific delivery of 5-ASA and evaluate the interaction between the polymers present in the systems. Additionaly, the physicochemical and rheological properties of xylan were also evaluated. Initially, xylan was extracted from corn cobs and characterized regarding the yield and rheological properties. Afterwards, 10 formulations were prepared in different xylan and ES100 weight ratios by spray-drying the polymer solutions in 0.6N NaOH and phosphate buffer pH 7.4. In addition, 3 formulations consisting of xylan microcapsules were produced by interfacial cross-linking polymerization and coated by ES100 by means of spray-drying in different polymer weight ratios of xylan and ES100. The microparticles were characterized regarding yield, morphology, homogeneity, visual aspect, crystallinity and thermal behavior. The polymer interaction was investigated by infrared spectroscopy. The extracted xylan was presented as a very fine and yellowish powder, with mean particle size smaller than 40μm. Regarding the rheological properties of xylan, they demonstrated that this polymer has a poor flow, low density and high cohesiveness. The microparticles obtained were shown to be spherical and aggregates could not be observed. They were found to present amorphous structure and have a very high thermal stability. The yield varied according to the polymer ratios. Moreover, it was confirmed that the interaction between xylan and ES100 occurs only by means of physical aggregation

Hemogasometria de eqüinos submetidos à obstrução experimental do duodeno, íleo e cólon maior

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Perfil eletroforético do proteinograma sérico de eqüinos com obstrução experimental do cólon menor

Avaliaram-se as alterações do proteinograma sérico de eqüinos submetidos à isquemia e reperfusão do cólon menor por distensão intraluminal. Foram utilizados 10 animais submetidos à laparotomia pelo flanco, em posição quadrupedal, para a indução de obstrução no cólon menor durante um período de quatro horas. Cinco animais foram instrumentados, mas sem distensão (grupo controle - G1). em cinco outros animais, foi realizada isquemia mural por distensão do cólon menor via manguito inflado com 40mmHg (grupo distendido - G2). Foram colhidas amostras de sangue antes da intervenção cirúrgica (M1), com 4 horas da colocação do manguito (M2) e com 3 horas (M3) e 12 horas (M4) de reperfusão. Após centrifugação e fracionamento das amostras, as proteínas de fase aguda foram separadas por eletroforese em gel de poliacrilamida contendo SDS-PAGE, e suas concentrações determinadas por densitometria computadorizada. Foram encontradas 19 proteínas no fracionamento eletroforético, com peso molecular variando de 185.000 a 14.000 Daltons (Da). Os pesos moleculares encontrados, correspondentes às proteínas mais conhecidas, foram ceruloplasmina, 130.000 Da; proteína C-reativa, 122.000 Da; transferrina, 85.000 Da; α1-antitripsina, 61.000 Da; haptoglobina, 47.000 Da; e glicoproteína ácida, 40.000 Da. Os resultados mostram que proteínas de fase aguda se alteram após o trauma cirúrgico.

Alterações morfométricas no plexo mioentérico do cólon menor equino distendido experimentalmente

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Características celulares e bioquímicas do líquido peritoneal de equinos submetidos à obstrução experimental do duodeno, íleo e cólon maior

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação histomorfométrica e ultra-estrutural da mucosa do cólon menor eqüino submetido a distensão

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Probióticos e prebióticos na atenção primária ao câncer de cólon

CONTEXTO: As neoplasias de cólon são a terceira forma mais comum de câncer atualmente. Seus tratamentos ainda estão associados a elevado risco de complicações, ressaltando, assim, a necessidade de elaborar novas estratégias de tratamento. A ingestão de probióticos, prebióticos ou a combinação de ambos (simbióticos), representa nova opção terapêutica. Diante da importância do equilíbrio quantitativo e qualitativo da microbiota intestinal para saúde humana e com objetivo de melhor elucidar o papel dos probióticos e prebióticos, o tema citado procura abordar a importância destes como coadjuvantes na prevenção e tratamento de câncer de cólon. METODOLOGIA: Foi realizada pesquisa em bancos de dados científicos (Medline, Lilacs, PubMed, Ovid, Scielo) através de levantamento de artigos científicos, além da busca direta aos periódicos, priorizando-se os mesmos do período de 2003 a 2008. Foram, também, coletadas informações através de sites da internet, como forma de melhor compreender a epidemiologia, conceitos e tratamentos dessa patologia. RESULTADOS: Estudos apontam relação inversa entre o consumo de probióticos e prebióticos e o diagnóstico de câncer de cólon, sendo que alguns dos possíveis mecanismos englobam: aumento da resposta imune, redução da resposta inflamatória, inibição de formação de células tumorais e da conversão de substâncias pré-carcinogênicas em carcinogênicas. CONCLUSÃO: Através da realização desta revisão literária foi possível obter respostas positivas quanto ao uso de probióticos e prebióticos na carcinogênese, colocando seu uso como recomendado de forma adequada.

Efeitos da injeção de solução bicarbonatada de ácido acetilsalicílico em mucosa colorretal de coelhos, com vistas a aplicação no preparo pré-operatório do cólon

INTRODUÇÃO: A recidiva local no câncer colorretal tem como principal causa o implante de células tumorais nas anastomoses. 11-15 Dessa maneira, lavagem química do lúmen intestinal é preconizada para evitar tanto o implante quanto à recidiva local. 11-28 em estudos prévios constatamos que a solução bicarbonatada de ácido acetilsalicílico tem efeitos citolíticos e anti-tumorais in-vitro.31 OBJETIVOS: Avaliar a toxicidade da solução de aspirina na mucosa colônica de coelhos com o objetivo de usá-la no preparo intestinal de portadores de câncer colorretal. MATERIAIS E MÉTODOS: Foram utilizados 20 coelhos. Um clampe vascular foi colocado acima do cólon sigmóide. Os animais foram submetidos a um enema com 50 ml da solução de aspirina ou soro fisiológico de acordo com o grupo. Os animais foram sacrificados ao término do procedimento ou tardiamente de acordo com o grupo. RESULTADOS: A solução de aspirina não altera a mucosa colônica de coelhos. CONCLUSÃO: O uso da solução bicarbonatada de ácido acetilsalicílico no preparo intestinal de portadores de câncer colorretal é clinicamente possível.

Adenocarcinoma de cólon com diferenciação neuro-endócrina e escamosa. Relato de caso.

A tubular adenocarcinoma of the colon with solid area composed by small cells that was found by immunohistochemistry study using antibody to neuron-specific enolase (NSE) to possess neuroendocrine differentiation is related. In another areas of the tumor were visualized keratinizing squamous cells. The presence of neuro-endocrine and squamous cells features provide further evidence that neoplastic colonic cells have the capacity for multi-directional differentiation. The implications of this combination in relation to theories of tumor origin and differentiation and the prognostic significance of neuro-endocrine cells in malignant neoplasms of the gastrointestinal tract are discussed.

Ação do diclofenaco de sódio, após a interrupção da peritonite estercorácea, no cólon de ratos. Estudo da resistência mecânica e do colágeno tecidual.

The objective of the present study was to investigate changes in colon wall in rats with fecal peritonitis (Per) associated with sodium diclofenac (SD) by studying breaking strength and tissue collagen concentration. The rats were divided into the following experimental groups: GROUP 1-SD: 60 animals injected intramuscularly with sodium diclofenac at the dose of 2 mg/kg body weight; GROUP 2-Per: 60 animals injected intraperitoneally with a suspension of human feces. Peritonitis was interrupted after six hours of evolution; GROUP 3-Per+SD: 60 animals injected intraperitoneally with a suspension of human feces and receiving SD according to the schedule used for Groups 1 and 2; CONTROL GROUP: 12 animals injected intramuscularly with physiological saline. The animals of Group 1, 2 and 3 were successively sacrificed 2, 4, 7, 14 and 21 days after interruption of peritonitis an/or the beginning of treatment. Under conditions of the experimental model and of the methods used, we conclude that sodium diclofenac, peritonitis and the peritonitis-sodium diclofenac association decrease the breaking strength and the concentration of tissue collagen in the colon segment.

Efeitos do parecoxibe no intestino delgado e cólon de rato: análise morfológica e da força de ruptura

Pós-graduação em Bases Gerais da Cirurgia - FMB

Efeitos da ingestão de Yacon (Smallanthus sonchifolius) sobre o processo de carcinogênese de cólon induzido pela 1, 2-dimetilhidrazina em ratos wistar

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)