Silsesquioxano solúvel em água, cloreto de 3-n-propil-1-azônia-4-azabiciclo[2.2.2]octano, enxertado sobre a superfície de Al/SiO2: estudo da adsorção de cromo

The water soluble material, 3-n-propyl-1-azonia-4-azabicyclo[2.2.2]octanechloride silsesquioxane (dabcosil silsesquioxane) was obtained. The dabcosil silsesquioxane was grafted onto a silica surface, previously modified with aluminum oxide. The resulting solid, dabcosil-Al/SiO2, presents 0.15 mmol of dabco groups per gram of material. The product of the grafting reaction was analyzed by infrared spectroscopy and N2 adsorption-desorption isotherms. The dabcosil-Al/SiO2 material was used as sorbent for chromium (VI) adsorption in aqueous solution.O material octanocloreto de 3-n-propil-1-azonia-4-azabiciclo[2.2.2] silsesquioxano (dabcosil silsesquioxano) solúvel em água foi obtido. O dabcosil silsesquioxano foi enxertado na superfície da sílica, previamente modificada com óxido de alumínio. O material sólido resultante dabcosil-Al/SiO2, apresentou 0,15 mmol de grupamentos dabco por grama do material. O produto enxertado foi caracterizado por espectroscopia de infravermelho, e isotermas de adsorção-dessorção de N2. O material dabcosilAl/SiO2 foi utilizado como sorvente para a adsorção de chromium(VI) em soluções aquosas.5358Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

‘Rotatinuous’ stocking: An innovation in grazing management to foster both herbage and animal production

‘Rotatinuous’ stocking is a grazing management strategy based on animal behavioural responses to sward structure which is designed to maximize herbage intake per unit of grazing time. It is an alternative to traditional grazing management practices focusing on pasture use efficiency and maximizing herbage accumulation and harvesting. To investigate this approach, Italian ryegrass (Lolium multiflorum) pastures grazed by sheep were evaluated in 2014 and 2015 under two contrasting grazing management strategies. Paddocks were distributed under a complete randomized block design with four replicates. Grazing management strategies were: traditional rotational stocking (RT), with pre- and post-grazing sward heights of 25 and 5 cm, respectively, and ‘Rotatinuous’ stocking (RN), with pre- and post-grazing sward heights of 18 and 11 cm, respectively. Thirty-two castrated Texel × Polwarth crossbred lambs were randomly allocated to treatments. As a consequence of grazing strategies, the stocking cycles were 12 and 4, with resting periods of 13 and 35 days, respectively, for RN and RT treatments. Herbage production, total herbage harvested, and feed conversion efficiency were 28%, 20%, and 40%, respectively, greater for RN than for RT treatment. Although the stocking rate was lower, the average daily gain per animal and live weigh gain per hectare were 153% and 43%, respectively, greater for the RN treatment. Despite the RN treatment being orientated to maximize herbage intake per unit of grazing time, it results in greater total herbage production and harvesting. We conclude that the ‘Rotatinuous’ stocking strategy is not necessarily reversed by low herbage harvesting efficiency. This innovation in grazing management conciliates high herbage and animal production at the same time

NO EVIDENCE OF PATHOLOGICAL AUTOIMMUNITY FOLLOWING MYCOBACTERIUM LEPRAE HEAT-SHOCK PROTEIN 65-DNA VACCINATION IN MICE

Heat-shock proteins (HSPs) are currently one of the most promising targets for the development of immunotherapy against tumours and autoimmune disorders. This protein family has the capacity to activate or modulate the function of different immune system cells. They induce the activation of monocytes, macrophages and dendritic cells, and contribute to cross-priming, an important mechanism of presentation of exogenous antigen in the context of MHC class I molecules, These various immunological properties of HSP have encouraged their use in several clinical trials. Nevertheless, an important issue regarding these proteins is whether the high homology among HSPs across different species may trigger the breakdown of immune tolerance and induce autoimmune diseases. We have developed a DNA vaccine codifying the Mycobacterium leprae Hsp65 (DNAhsp65), which showed to be highly immunogenic and protective against experimental tuberculosis. Here, we address the question of whether DNAhsp65 immunization could induce pathological autoimmunity in mice. Our results show that DNAhsp65 vaccination induced antibodies that can recognize the human Hsp60 but did not induce harmful effects in 16 different organs analysed by histopathology up to 210 days after vaccination. We also showed that anti-DNA antibodies were not elicited after DNA vaccination. The results are important for the development of both HSP and DNA-based immunomodulatory agents