123 resultados para Câncer de pulmão não pequenas células


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Bacillus thuringiensis (Bt), is an environmental Gram-positive spore-forming bacterium that produces crystalline parasporal protein (Cry) during sporulation. The inclusions often exhibit strong and specific insecticidal activity, making Bt an agent for agricultural controlling insects pest, mites, protozoa and nematodes. Recent studies reported that some of these Crys do not show cytotoxicity against insects but they are capable to kill some human and animal cancer cells. These proteins were denominated parasporins (PS). However, antitumor activity of Bt parasporin on the development of murine colorectal cancer (CT-26), are not well studies and these are no reports on the in vivo effect of these proteins. Thus, the present study evaluated the in vitro and in vivo anti-tumoral activity of Bt parasporin against the murine colorectal cancer line CT-26. Therefore, Balb/c mice were s.c. inoculated with CT-26 cells and weekly treated with parasporin (i.p.) pre-activated by enzymatic digestion with trypsin or proteinase K. Our results have shown, for the first time, that despite the anti-tumor activity in vitro, parasporin crystals couldn’t combat tumor growth in vivo. Instead, this protein was highly toxic, affecting the liver and spleen, with possible effect on other organs, decreasing the survival of treated animals. The results indicate the need for studies to better detoxification or manipulation of parasporin for therapeutic use and new studies for analysis of toxicological effects of repetitive exposure of farmers to this toxin

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O câncer, manifestação originada pelo crescimento descontrolado de células, afeta milhões de indivíduos. Os macrófagos são as primeiras células a serem ativadas para participar de uma resposta imunológica propriamente dita, são células capazes de secretar mais de cem produtos biologicamente ativos, entre esses, espécies reativas de nitrogênio e citocinas que atuam no contexto da resposta imunológica e/ou inflamatória. Sabendo que compostos de paládio (II) podem apresentar potenciais atividades antitumorais, neste trabalho foram testado os compostos de fórmula geral PdI2 (tdmPz) e Pd (SCN)2 (tdmPz), quanto a atividade anti-inflamatória e antitumoral. Como droga padrão das reações realizadas foi utilizada a cisplatina. Foi determinada a ação destes compostos frente ao sistema imunológico através, de ensaios de determinação de índice de citotoxicidade mediano (IC50) pela técnica de MTT, óxido nítrico (NO) e determinação das citocinas pró-inflamatórias TNF- e IL-12. Além disso, foi determinada a atividade antitumoral dos compostos frente à célula tumoral de Ehrlich. Os resultados não mostraram produção de NO e das citocinas IL-12 e TNF- pelos macrófagos peritoneais de animais normais e animais portadores do tumor de Ehrlich na sua forma sólida. No que se referem à atividade tóxica dos compostos testados, estes mostraram efeito citotóxico sobre os macrófagos e sobre a linhagem tumoral testada. Sendo assim mesmo não havendo a produção de mediadores próinflamatórios, os compostos apresentaram uma considerável citotoxicidade frente às células tumorais de Ehrlich e macrófagos peritoneais

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Helicobacter pylori (H. pylori) is a common gastric pathogen that has infected more than 50% of the population of the world and it has been associated with chronic gastritis, gastric ulcers, duodenal ulcer, and gastric cancer. Although, almost all infected people develop gastritis, there is a variety of clinical outcomes, and only a minority (<1%) of infected individuals develop gastric cancer. There are evidences which suggest that the chronic inflammatory reaction caused by the bacterial infection may be involved in the production of reactive oxygen species or reactive nitrogen species. It may lead to DNA damage, which together with the cellular response could lead to gene mutations, chromosomal aberrations characterizing genomic instability that may represent the early step in gastric carcinogenesis. The extent and severity of gastric mucosal inflammation, as well as the clinical outcome of the infection, depend on a number of factors, including the host genetic susceptibility such SNP T3801 CYP1A1, immune response, age at which the infection was acquired, environmental factors, especially dietary and bacterial virulence factors. Due to the risk of developing gastric cancer in humans infected by H. pylori, we used the Comet Assay to investigate the influence of the SNP T3801C CYP1A1 on levels of oxidative DNA damage in gastric epithelial cells. The study was conducted with biopsies from the gastric antrum and corpus of 103 H. pylori-infected patients and 24 uninfected control patients. Genotype of SNP T3801C CYP1A1 was determined by PCR-RFLP and DNA damage levels were measured in gastric mucosal cells from antrum and corpus by the Comet assay. Levels of DNA damage in gastric mucosa cells from antrum and corpus of H. pylori-infected patients with mild, moderate, severe gastritis, and gastric cancer were significantly higher compared to uninfected normal mucosa cells. However, levels... (Complete abstract click electronic access below)

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(Microarray technology in study of head neck cancer). The microarray technology is a tool for global analysis of gene expression that allows investigating hundreds or thousands of genes in a sample using a hybridization reaction. This technology is based on hybridization between labeled targets derived from biological samples and an array of many DNA probes immobilized on a solid matrix, representing the genes of interest. The simultaneous study of hundreds of genes became the microarray technique a very important tool of global analysis, with applications in several areas, including the study of the development of cancer. Head and neck squamous cell carcinoma (HNSCC) is the fifth most common cancer worldwide, with a global annual incidence of 780,000 new cases. Large-scale studies involving microarrays have identified specific gene expression signatures associated with expression changes in HNSCC samples compared to normal tissue, as well as genes involved in clinical outcome and metastasis. However, the considerable heterogeneity among these studies occurs due to experimental design, number of samples, disease sites and stage, choice of microarray platform and results validation. Thus, there is much to be validated, before the technique has clinical utility. In relation to head and neck neoplasia, the large-scale gene analysis is very important, since the clinical and histopathological methods currently used appear to be insufficient to predict clinical progression and response to treatment. Thus, this approach could result in more effective diagnostic and prognostic and most appropriate therapy for this neoplasia.

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

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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

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Aloe vera (Aloe barbadensis Miller), popularly known in Brazil as babosa, has a long history of use as medicinal plant for different therapeutic purposes. The components of the plant extract are present in various products of human use, mainly for nutritional and cosmetics purposes. However, some studies suggest that this extract might also have carcinogenic activity. The aloe vera extract is a complex mixture of bioactive compounds. The study of isolated compounds may contribute to elucidate contradictory results about the effects related to the consumption of the plant, as well as their mechanisms of action. One of the most important compound from Aloe vera is aloe-emodin, which is a secondary metabolite generated in the intestinal tract. Putative antimicrobial and antitumor effects were previously attributed to aloe-emodin. Although the exposure of urothelial cells to aloe-emodin was already reported in the literature, only one study showed its effects on urothelial cells, suggesting that aloe-emodin inhibits the viability of T24 cancer cells due to apoptosis induction. Since there is no sufficient information about the effects of aloe-emodin on urothelial cells, and low efficiency in the treatment of bladder cancer currently, the present study aims to evaluate the hypothesis that the treatment with aloe-emodin could impact the behavior of other urothelial cell lines in vitro. Therefore, the in vitro IC50 exposure of aloe-emodin to human immortalized neoplastic urothelial cells will be determinated in order to verify possible differences in the behavior of urothelial cells in vitro treated with aloe-emodin in comparison with untreated cells. Furthermore, differences between cell lines will be also evaluated

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O câncer é uma doença que tem início quando ocorre uma mutação genética no DNA da célula, onde o mecanismo de controle do crescimento normal do tecido celular é alterado. O tratamento do câncer por radioterapia tem como objetivo a eliminação das células cancerígenas ou alívio dos sintomas. Este trabalho visa estudar conceitos envolvidos no planejamento do tratamento de câncer por radioterapia, o modelo de programação linear, os métodos Primal-Dual-Afim-Escala e Primal-Dual-Clássico e apresentar uma aplicação dos métodos para problemas gerais de otimização

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)