BackgroundStudies have shown that radiation from radiotherapy increases the yeast colonization of patients. However it is not clear, if such radiation alters the yeast itself. The aim of the present study was therefore to report the direct impact of gamma radiation on Candida tropicalis. Methods C. tropicalis was obtained from a patient with a carcinoma, a suspension of this yeast containing 2.0 × 103 colony forming units per milliliter was prepared. It was submitted to gamma radiation dosage similar to that used in the treatment of head and neck cancer. After a cumulative dose of 7200 cGy some virulence attributes of C. tropicalis, including macro and micromorphological characteristics, adhesion and biofilm abilities, murine experimental infection and phagocytosis resistance were evaluated on irradiated and non-irradiated yeasts.ResultsAfter irradiation the colony morphology of the yeast was altered from a ring format to a smooth appearance in most colonies. Scanning electron microscopy revealed notable differences in the structures of both these colonies and the yeast cells, with the loss of pseudohyphae following irradiation and an increase in extracellular matrix production. The adherence and biofilm production of the yeast was greater following irradiation, both in terms of the number of yeasts and total biomass production on several abiotic surfaces and TR146 cells. The phagocytic index of the irradiated yeasts was not statistically different; however, the presence of cellular debris was detected in the kidneys of infected animals. Mice infected with irradiated yeasts developed an infection at the site of the yeast inoculation, although systemic infection was unchanged.ConclusionsOur findings show for the first time that C. tropicalis, one of the most important yeasts from colonization, which cause fatal candidemia in cancer patients, is affected by gamma irradiation, with changes to its virulence profile.

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Several daily activities are performed through digital devices, so there is no way to disregard them in the most varied sectors. Therefore, educational institutions have already under stood that digital resources are important for learning and, therefore, some text books have already incorporated these tools as part of their material. Thus, this article analyzes the teaching concepts existing in the Digital Educational Objects (OEDs) of the Portuguese digital textbook: language in connection (2013), by the authors Maria das Graças Leão Sette, Márcia Antônia Travalha and Maria do Socorro Starling de Barros. The theoretical foundation is based on the assumptions of prescriptive, descriptive and productive teaching, based mainly on Halliday (1974) andTravaglia (2002). For analysis, we surveyed the OEDs and assisted each one in order to identify such teaching concepts. The results of the investigation indicate that, in the analyzed OEDs, there is the presence of three types of teaching: prescriptive, descriptive and productive.

Analisamos, neste trabalho, as concepções de língua(gem),destacando também as concepções de leitura/literatura, nos Objetos Educacionais Digitais (OED) do livro didático digital Português: linguagens em conexão (2013), das autoras Maria das Graças Leão Sette, Márcia Antônia Travalha e Maria do Socorro Starling de Barros. A base teórica dessa pesquisa está sustentada em Bakhtin ([1929] 2014), Fuza, Ohuschi e Menegassi (2011), Geraldi (1999), Oliveira (2010), Travaglia (2002), dentre outros. O estudo é uma pesquisa de natureza qualitativa e de cunho documental, pois analisamos documentos presentes no contexto de ensino, ou seja, OED e livro didático de português. Para a viabilização dessa pesquisa, seguimos os seguintes passos metodológicos: (i) realizamos o levantamento dos OED do eixo leitura e ensino de imagens no referido livro; (ii) assistimos a cada um dos OED; (iii) analisamos os OED do livro, considerando a categoria de análise concepções de língua(gem) e de leitura. Os resultados da investigação indicam que há uma hibridização das concepções de língua(gem) nos OED analisados. Apesar disso, verificamos que há uma maior predominância das concepções de linguagem como expressão do pensamento e como instrumento de comunicação, em detrimento da linguagem como interação verbal.