Vitamin D plays an important role in many physiological processes, particularly calcium and phosphorous homeostasis. The biochemistry of vitamin is also complex, encompassing a range active molecules that may be either endogenous or dietary origin. lipids fats the production, processing use interesting one, with relative paucity model studies into interactions lipidic systems such as micelles v...

Supplemental vitamin D is available in 2 distinct forms: ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3). Pharmacopoeias have officially regarded these 2 forms as equivalent and interchangeable, yet this presumption of equivalence is based on studies of rickets prevention in infants conducted 70 y ago. The emergence of 25-hydroxyvitamin D as a measure of vitamin D status provides a...

There is a high prevalence of vitamin D deficiency worldwide, but how to define vitamin D deficiency is controversial. Currently, the plasma concentration of total 25-hydroxyvitamin D [25(OH)D] is considered an indicator of vitamin D status. The free hormone hypothesis states that protein-bound hormones are inactive while unbound hormones are free to exert biological activity. The majority of c...

Vitamin D plays a major role in bone mineral homeostasis by promoting the transport of calcium and phosphate to ensure that the blood levels of these ions are sufficient for the normal mineralization of type I collagen matrix in the skeleton. In contrast to classic vitamin D-deficiency rickets, a number of vitamin D-resistant rachitic syndromes are caused by acquired and hereditary defects in t...

The absorption and metabolism of vitamin D(3)-(3)H was studied in eight patients with chronic renal failure. Although the intestinal absorption of vitamin D(3)-(3)H was normal, the metabolic fate of the vitamin was abnormal as characterized by a twofold increase in fractional turnover rate, an abnormal accumulation of biologically inactive lipid-soluble metabolites, and the urinary excretion of...

The analysis of the maintenance of a metabolite of vitamin D (25dihydroxyvitamin D) and vitamin D-binding protein in the blood serum of children under 3 years, patients with pneumonia. Found that a child with pneumonia is characterized by a significant decrease in blood serum concentrations of 25-dihydroxyvitamin D and vitamin D-binding protein. Additional risk factors for pneumonia in young ch...

Carp (Cyprinus carpio), a freshwater fish that lives in a low-calcium environment, and Atlantic cod (Gadus morhua), a seawater fish that lives in a high-calcium environment, were studied for the presence of a novel membrane binding protein ("receptor") for the vitamin D metabolite, 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)]. Basal lateral membranes from enterocytes of either species were prep...