It is now well established that carotene is a precursor of vitamin A, and its transformation into the vitamin is a function of the animal organism. During studies of the mechanism of this change, attention has been focused mainly on the liver, the storehouse of vitamin A in the animal body, and at least one investigator has claimed that the change takes place in the liver through the action of ...

We investigated the effects of dietary supplementation of zinc (Zn) with or without vitamin A (Vit. A), to elucidate any cross activity between the two micronutrients, on memory and nerve growth factor (NGF) production in ddY male mice depleted for the two elements. After 3 mo-feeding with a Zn and Vit. A deficient (VAD) diet, mice were divided into three groups and replenished with normal Zn w...

Chou et al. discover a new mode of maternal inheritance by analyzing human mutations in plasma retinol binding protein (RBP). Mechanistically, these mutations simultaneously lower RBP's affinity for vitamin A and greatly increase its affinity for its cell-surface receptor, thus dominantly blocking the transmembrane transport of vitamin A.

We previously reported the presence of brown/beige adipocytes in the white fat depots of mature cattle. The present study examined the effects of dietary vitamin A on the expression of brown/beige adipocyte-related genes in the white fat depots of fattening cattle. No significant differences were observed in the expression of Ucp1 between vitamin A-deficient cattle and control cattle. However, ...

OBJECTIVE To investigate the vitamin A status of pregnant mothers, lactating mothers, preterm and term infants who were being fed exclusively on breast milk. DESIGN Systematic/cross sectional. SETTING Vitamin A research laboratory, animal science research laboratory, University of Zimbabwe, and Harare Central Hospital. SUBJECTS 105 pregnant mothers attending the antenatal clinic at Harare...

BACKGROUND Orange-fleshed sweetpotato (OFSP) can be used to tackle vitamin A deficiency, a major public health problem in most developing countries. In East Africa, common ways of using sweetpotato include drying and subsequent storage. The aim of the study was to investigate the impact of drying and storage on the total carotenoid retention (as an estimate of provitamin A retention) from OFSP....

BACKGROUND Vitamin A deficiency is an important dietary deficiency in the world. Thus, the ne¬cessity of screening for deficient populations is obvious. This paper introduces a fast, cheap and relatively reliable method called "dried blood spot" (DBS) method in screening the deficient populations. The validity of this method for retinol measurement was investigated. METHOD The "precision" and...

Vitamin A deficiency (VAD) and iron deficiency anemia (IDA) have been recognized as public health problems in Honduras for over 30 years. This paper, based on the 1996 National Micronutrient Survey on 1678 children 12-71 months of age, presents the results for vitamin A status and anemia prevalence, as well as the level of vitamin A in sugar at the household level. The results showed that 14% o...

Perfusion feeding in rats induced a decrease in circulating retinol despite an adequate supply of vitamin A. We studied the effect of total parenteral nutrition (TPN) on the retinol specific carrier in rat, analyzing holo-RBP (bound to retinol) and apo-RBP (without retinol) in serum and in liver. Vitamin A-sufficient (A+) and -deficient (A-) rats were characterized in terms of vitamin A and RBP...

Vitamin A deficiency is the most important cause of childhood blindness in lower and middle income countries, and contributes significantly to morbidity and mortality from common childhood infections. Beaton and colleagues’ metaanalysis of randomized community-based trials in eight countries concluded that vitamin A supplementation resulted in a 23% reduction in the mortality rates of children ...