OBJECTIVE: This study aims to evaluate the production of interferon-gamma and interleukin-10 by stimulated peripheral blood mononuclear cells isolated from patients with supraglottic laryngeal cancer before and after surgical treatment. METHODS: Fourteen patients with advanced supraglottic laryngeal cancer were studied. Cultures of peripheral blood mononuclear cells isolated during the preoperative and late postoperative periods were stimulated with concanavalin A and Bacille Calmette-Guerin, and the supernatant concentrations of interferon-gamma and interleukin-10 were measured. RESULTS: For non-stimulated cultures, the interferon-gamma levels produced by the preoperative period and the late postoperative period cultures were lower than the levels produced by the control group cultures. The interferon-gamma levels after stimulation with concanavalin A were higher in the late postoperative period cultures than in the preoperative evaluation cultures. Stimulation with Bacille Calmette-Guerin led to the production of similar levels of interferon-gamma and interleukin-10 by all cultures; thus, stimulation increased the levels of interferon-gamma produced by both the preoperative and postoperative cultures relative to the levels produced by the corresponding unstimulated cultures. CONCLUSION: Patients with advanced supraglottic laryngeal cancer exhibit an in vitro deficiency in interferongamma secretion by mononuclear cells. Stimulated cells seem to recover this function during the postoperative period.

A 1µs Molecular Dynamic simulation was performed with a realistic model system of Sodium Dodecyl Sulfate (SDS) micelles in aqueous solution, comprising of 360 DS-, 360 Na+ and 90000 water particles. After 300 ns three different micellar shapes and sizes 41, 68 and 95 monomers, were observed. The process led to stabilization in the total number of SDS clusters and an increase in the micellar radius to 2.23 nm, in agreement with experimental results. An important conclusion, is be aware that simulations employed in one aggregate, should be considered as a constraint. Size and shape distribution must be analyzed.

O presente estudo teve como objetivo avaliar o efeito das baixas doses da radiação gama na concentração de carotenóides totais, alfa e beta-caroteno em cenouras minimamente processadas, durante a vida-útil. As cenouras são as principais fontes de carotenóides provitamínicos A (alfa e beta-caroteno) de origem vegetal. De acordo com a Pesquisa de Orçamento Familiar (POF) realizada na região Sudeste do Brasil, no grupo de raízes e tubérculos a cenoura é amplamente consumida. A estabilidade dos carotenóides varia grandemente durante o processamento e o armazenamento, dependendo de sua estrutura, temperatura, oxigênio, luz, umidade, atividade de água e presença de ácidos e metais antioxidantes e pró-oxidantes. As cenouras minimamente processadas neste experimento foram manualmente descascadas, lavadas, cortadas mecanicamente, acondicionadas em embalagens com atmosferas modificadas de 5% O2 / 10% CO2 e 21% O2 (ar sintético), tratadas com radiação ionizante gama, fonte de césio, nas doses de 0,25, 0,50, 0,75 e 1,00kGy, e armazenadas a 5°C durante 24 dias. Os carotenóides totais foram quantificados por espectrofotometria a 449nm. Para a determinação de alfa e beta-caroteno utilizou-se cromatografia líquida de alta eficiência (CLAE). Os diferentes tratamentos e o grupo controle foram, também, avaliados através das análises de cor e voláteis, por cromatografia gasosa/espectrometria de massas associada à microextração em fase sólida (CG-EM/MEFS), para estudar as perdas dos carotenóides durante o processamento.

This study aims was to evaluate the effect of low doses of gamma radiation on the total carotenoids, alpha and beta-carotene content in minimally processed carrots, during the shelflife. Carrots are the mains vegetable source of carotenoids provitamin A (alpha and beta-carotene). According to the Family Budget Survey (FBS) carried out in the Brazilian Southeast, within the roots and tubers group, carrots are widely consumed. The carotenoid stability varies largely during the stages of processing and storage, depending upon structure, temperature, oxygen availability, light exposure, humidity content, water activity and acid, metal anti-oxidant and pro-oxidant presence. The minimally processed carrots in this experiment were manually peeled, rinsed, cutted into diskis, packaged under 5% O2 / 10% CO2 and 21% O2 (sintetic air), gamma ionizing radiation treatments was carried out with a 137Cs source, of 0,25, 0,50, 0,75 and 1,0kGy doses, and shelf-stored at 5°C for 24 days. Total carotenoids quantification was by 449nm spectrophotometer. Determination of a and beta-carotenes was made by High Performance Liquid Chromatography (HPLC). The different treatments and control group were, too, evaluated by analysing of colour and volatiles, by gas chromatography/mass spectroscopy with solid phase microextration (CG-MS/SPME), for study the significant carotenoids losses during the process.

Simulações de Monte Carlo foram realizadas para soluções aquosas concentradas de uréia nas concentrações de 4, 5, 6, 7 e 8 mol L-1 no ensemble NpT a 298 K e 1 atm. As superfícies de energia potencial foram representadas pela soma dos potenciais clássicos de Coulomb e de Lennard-Jones, nos quais a aditividade de pares foi considerada. Nas simulações a água foi descrita pelo modelo TIP4P e a uréia por dois modelos: o modelo OPLS planar e um modelo no qual a molécula de uréia não é totalmente planar. Os resultados das simulações para os dois modelos mostraram que a uréia não causa perturbações significativas na estrutura da água, na faixa de concentrações estudadas. No entanto, foi observada diminuição do número médio de ligações de hidrogênio entre as moléculas de água. Para as soluções mais concentradas os resultados obtidos com o modelo OPLS sugerem a formação de dímeros de uréia. Observou-se similaridade entre alguns dos resultados das simulações obtidos com os modelos: OPLS planar e não-planar da uréia , nas mesmas concentrações e condições.

Monte Carlo simulations were carried out for concentrated aqueous urea solutions at 4, 5, 6, 7 and 8 mol L-1 in the NpT ensemble at 298 K and 1 atm. The potential energy surfaces were represented by the sum of Coulomb and Lennard-Jones potentials in which pair-wise additivity was considered. Water was described by the TIP4P model, while urea was described by the OPLS planar model and also by a proposed non-planar model. The simulation results for both urea models showed that urea does not induce any significant changes in the structure of water over all the concentrations studied. However, it was noted that the number of hydrogen bonds between the water molecules decrease as the concentration increases. The simulation results of the OPLS planar model suggest the formation of urea dimers in the more concentrated solutions. The simulations with the non-planar model showed several features similar to those of the OPLS planar model.