Nutrition
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In critically ill patients there is consistent evidence that significant benefits are achieved if nutrients are delivered within the gut compared with the parenteral route. However, in conditions related to gut hypoflux, enteral nutrition may play a double role in counterbalancing the installed low-flow state. On the one hand, enteral-induced postprandial hyperemia may preserve the mucosal barrier and ameliorate immune competence; on the other hand, feeding by the gut may pose a theoretical risk of intestinal ischemia. ⋯ Arginine may prevent intestinal injury due to hypoperfusion but may harm the gut if ischemia is established. In contrast, glutamine may promote benefits in both conditions. Further investigations by randomized trials in this field are necessary.
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We investigated if alterations in the insulin-signaling pathway could contribute to reduced hepatic glycogen levels in adult rats subjected to a protein deficiency during intrauterine life and lactation and reared through to recovery on a soybean diet. ⋯ Adult rats maintained with a soybean diet exhibited insulin resistance due, at least in part, to alterations in the early steps of the insulin signal transduction pathway.
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Hypothalamic centers integrate external signals of nutrient availability and energy status and initiate responses to maintain homeostasis. Quantifying changes in hypothalamic gene expression in the presence of nutrient excess may identify novel responsive elements. ⋯ Expression of five genes involved in availability of dopamine was increased after a high-fat diet. Failure to reduce dopamine availability sufficiently, to counter the feeding reward effect, could contribute to diet-induced obesity in these mice.
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Comparative Study
Comparative 25-OH-vitamin D level in institutionalized women older than 65 years from two cities in Spain and Argentina having a similar solar radiation index.
The present study evaluated and compared vitamin D nutritional status and calcium-phosphorus metabolism in institutionalized women >65 y from two cities that have a similar sun irradiation index (heliophany). ⋯ Even at the end of summer, vitamin D deficiency/insufficiency was prevalent in the two studied institutionalized elderly women. In the narrow range of the dietary calcium intake (close to 800 mg/d) of both studied groups, secondary hyperparathyroidism was absent when 25OHD levels were >17 ng/dL, indicating changes in the regulation control of serum PTH and consequently the changes in this threshold. As a result, vitamin D deficiency must be reversed to avoid the increment in bone turnover and to ensure the endocrine and paracrine functions of vitamin D for overall health and well-being.
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Recent evidence has suggested a role for vitamin D in breast cancer prevention and survival. Studies have reported an inverse relation between vitamin D intake and the risk of breast cancer, improvements in survival after a diagnosis of breast cancer in women with higher levels of vitamin D, and vitamin D insufficiency in up to 75% of women with breast cancer. ⋯ Although ongoing studies have investigated a possible link between adequate levels of vitamin D and improved cancer prognosis, breast cancer survivors may derive additional, non-cancer-related benefits from adequate vitamin D levels, including improvements in bone mineral density, quality of life, and mood. Maintaining adequate vitamin D stores is recommended for breast cancer survivors throughout their lifetime.