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The understanding of the essential role of selenium (Se) in thyroid hormone synthesis, metabolism and action, as well as normal thyroid function, increased during the past decades. The thyroid gland is among the human tissues with the highest Se content per mas unit, similar to other endocrine organs and brain. Biological actions of Se are mediated, in most cases, through the expression of at least 30 selenoproteins coded by 25 selenoprotein genes in the human. Via the selenoproteins, selenium can influence the cell function through antioxidant activites, modifying redox status and thyroid hormone synthesis and metabolism. Selenoproteins iodothyronine deiodinases are present in most tissues and have a role to increase the production of bioactive tri-iodothyronine. Futhermore, Se has been shown to be important in the regulation of immune function. Se deficiency is accompained by the loss of immune competence. The links between Se deficiency, altered immune function and inflamation have prompted studies in humans to examine if Se suplementation can modify auto-antibodies production in patients with chronic autoimmune thyroiditis. Until now, several randomised prospective clinical trials have been performed in patients with established chronic autoimmune thyrioditis. The clinical endpoint of each study was the decrease in TPO antibodies concentration after 3-12 months of treatment. Ussualy, the dosage of daily Se supplementation was 200μg. Selenium suplemetation had no significant effect on the concentration of TSH or thyroid hormone concentrations. These studies indicate that Se treatment result in reduced inflammatory activity, but it does not cure chronc autoimmune process. [ABSTRACT FROM AUTHOR]

The common bean has been object of breeding programs aiming the development of new cultivars adapted to varied production system and shown differentiated nutritional characteristics. Due a genetic diversity existent the landraces can be used directly for cropping, for present characteristics desirable. Little information exists about mineral content and other quality traits for those bean landraces. The aim of this paper was to verify the variability for grain nutritional characteristics in breeding cultivars and landraces of bean from Rio Grande do Sul state, Brazil. The experiment was conducted in 2009/2010 in Experimental Station Cascata, of Embrapa Temperate Agriculture. In whole grain of 54 bean genotypes with black and no black coat were determined macroelements (nitrogen, phosphorus, potash, calcium, magnesium and sulfur), oligoelements (iron, manganese, zinc and cuprum), protein and ash content, insoluble fiber, digestive nutrient and antioxidant astragalina. The results shown that the landraces varieties presents nutritional composition of macro and oligoelements, fibers, protein and ash contents in whole grain similar than that of breeding lines and cultivars. The black coat grain from breeding programs showed better nutritional quality for macro and oligoelements content than coloured grain, highlighting TB 02-04 e TB 01-01. The landraces with coloured grains TB 02-26, TB 02-24 and TB 03-13 showed the high levels of astragaline. [ABSTRACT FROM AUTHOR]

Abstract: Intestinal cancers are correlated with diet. Thus, determining and understanding nutrient-genome interactions is important. The present work assessed the action of the oligoelement selenium on cell proliferation, cytotoxicity, and in situ apoptosis induction and on the expression CASP9, BCL-XL and APC genes in intestinal adenocarcinoma cells (HT29). HT29 cells were cultured and treated with selenium at concentrations of 5, 50 and 500ng/mL with or without the damage-inducing agent doxorubicin. These cells were then evaluated for cytotoxicity (MTT), cell proliferation and in situ apoptosis induction. To evaluate gene expression, only the cells treated with 500ng/mL of selenium were used. RNA was extracted from these cells, and the expressions of CASP9, BCL-XL and APC were analyzed by the RT-PCR method. The GAPDH gene was used as a reference gene. The MTT assay showed that selenium was not cytotoxic at any of the concentrations tested. The cell proliferation assay showed that selenium did not interfere with cell proliferation at the three concentrations tested. In contrast, when the three concentrations were combined with doxorubicin, a significant decrease in the proliferation rate was observed. The apoptosis rate was significantly increased in the selenium (500ng/mL) and doxorubicin group. CASP9 expression was increased and BCL-XL expression decreased in the selenium (500ng/mL) and doxorubicin group. APC was significantly increased in the selenium group alone. These results show that selenium increases apoptosis, especially when it is associated with a damage-inducing agent. Also, selenium has an important role in the expression of the APC gene, which is related to cell cycle regulation. [Copyright &y& Elsevier]