64 research outputs found
Threonine utilization is high in the intestine of piglets
The whole-body threonine requirement in parenterally fed piglets is
substantially lower than that in enterally fed piglets, indicating that
enteral nutrition induces intestinal processes in demand of threonine. We
hypothesized that the percentage of threonine utilization for oxidation
and intestinal protein synthesis by the portal-drained viscera (PDV)
increases when dietary protein intake is reduced. Piglets (n = 18)
received isocaloric normal or protein-restricted diets. After 7 h of
enteral feeding, total threonine utilization, incorporation into
intestinal tissue, and oxidation by the PDV, were determined with stable
isotope methodology [U-(13)C threonine infusion]. Although the absolute
amount of systemic and dietary threonine utilized by the PDV was reduced
in protein-restricted piglets, the percentage of dietary threonine intake
utilized by the PDV did not differ between groups (normal protein 91% vs.
low protein 85%). The incorporation of dietary threonine into the proximal
jejunum was significantly different compared with the other intestinal
segments. Dietary, rather than systemic threonine was preferentially
utilized for protein synthesis in the small intestinal mucosa in piglets
that consumed the normal protein diet (P < 0.05). Threonine oxidation by
the PDV was limited during normal protein feeding. In protein-restricted
pigs, half of the total whole-body oxidation occurred in the PDV. We
conclude that, in vivo, the PDV have a high obligatory visceral
requirement for threonine. The high rate of intestinal threonine
utilization is due mainly to incorporation into mucosal protein
A História da Alimentação: balizas historiogråficas
Os M. pretenderam traçar um quadro da HistĂłria da Alimentação, nĂŁo como um novo ramo epistemolĂłgico da disciplina, mas como um campo em desenvolvimento de prĂĄticas e atividades especializadas, incluindo pesquisa, formação, publicaçÔes, associaçÔes, encontros acadĂȘmicos, etc. Um breve relato das condiçÔes em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biolĂłgica, a econĂŽmica, a social, a cultural e a filosĂłfica!, assim como da identificação das contribuiçÔes mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histĂłrica, foi ela organizada segundo critĂ©rios morfolĂłgicos. A seguir, alguns tĂłpicos importantes mereceram tratamento Ă parte: a fome, o alimento e o domĂnio religioso, as descobertas europĂ©ias e a difusĂŁo mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rĂĄpido balanço crĂtico da historiografia brasileira sobre o tema
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