The dose of vitamin D that some researchers recommend as optimally therapeutic exceeds that officially recognized as safe by a factor of two; it is therefore important to determine the precise mechanism by which excessive doses of vitamin D exert toxicity so that physicians and other health care practitioners may understand how to use optimally therapeutic doses of this vitamin without the risk...

Serum undercarboxylated osteocalcin (ucOC) is an index of vitamin K nutritional status in treatment-naive postmenopausal osteoporotic women. The purpose of the present study was to reveal the association between vitamin K nutritional status and serum ucOC concentrations in postmenopausal osteoporotic women taking bisphosphonates. Eighty-six postmenopausal women with osteoporosis (age range: 47-...

Policies for giving babies vitamin K prophylactically at birth have been dictated, over the last 60 years, more by what manufacturers decided on commercial grounds to put on the market, than by any informed understanding of what babies actually need, or how it can most easily be given. By a pure fluke a 1 mg IM dose, designed to prevent early vitamin deficiency bleeding ("haemorrhagic disease o...

The development of vascular calcification is an active, highly regulated process with similarities to bone formation. Osteocalcin (OC), a vitamin K-dependent protein expressed by osteoblasts, contains 3  -carboxyglutamic acid residues derived from the vitamin K-dependent posttranslational modification of glutamic acid residues. Circulating undercarboxylated OC (ucOC) is increased in vitamin K ...

OBJECTIVE Osteopenia is a common complication of juvenile idiopathic arthritis (JIA). In adults, low bone density and increased fracture risk are associated with low vitamin K status of bone. The vitamin K-dependent protein osteocalcin plays an important role in bone metabolism. Its activity depends upon post-translational carboxylation in which vitamin K is an essential co-factor. Hence, vitam...

Protein S is a vitamin K-dependent plasma protein that inhibits the process of blood coagulation via activation of protein C, another vitamin K-dependent plasma protein A 58-year-old man with hereditary protein S deficiency had repeated attacks of acute myocardial infarction at age 52 and 58 years.

obesity is one of the health problems in the developing and developed countries. obesity subjects the individuals with metabolic and endocrine disorders. it is obvious that vitamin d deficiency or insufficiency may lead to secondary hyperparathyroidism. thus, obesity increases the risk of vitamin d deficiency. considering the high prevalence of vitamin d deficiency in children and adolescents w...

Vitamin B12 (cobalamin) is an essential coenzyme for nucleic acid synthesis. Animal protein is the major dietary source of vitamin B12. Deficiency of vitamin B12 leads to megaloblastic anemia, degeneration of the brain, spinal cord, peripheral nerves, and abnormalities of epithelial tissues. Two factors are necessary for the cure of megaloblastic anemia: one in food (extrinsic factor) and one i...

The role of vitamin K in the synthesis of prothrombin has been examined with the following results. 1. Vitamin K deficiency has no effect on general protein synthesis as studied by amino acid incorporation into protein in vivo and in vitro and by tryptophan pyrrolase production following tryptophan feeding. 2. Prothrombin activity was found in normal rat liver microsomes with increased release ...

backgrounds: vitamin d deficiency is a public health concern even in sunny areas, so we decided to assess the prevalence of vitamin d deficiency and its related factors among university students in shiraz. methods: this cross‑sectional study was carried out on 254 (128 male and 126 female) university students. demographic questionnaires and a questionnaire on exposure to sun light and sun prote...