LOCATION OF VITAMIN B12 IN HUMAN ERYTHROCYTES

Thiocyanate metabolism in human vitamin B12 deficiency.

Patients with subacute combined degeneration who smoked had significantly lowered plasma thiocyanate levels than control smokers, but plasma thiocyanate levels in non-smoking patients with neurological disease due to vitamin B(12) deficiency were not significantly different from control values. The results provide no support for the hypothesis that chronic cyanide intoxication is responsible fo...

Human dietary deficiency of vitamin B12.

Vitamin B12 levels in erythrocytes in normal subjects and in pernicious anaemia.

A reliable method is described for the assay of vitamin B(12) activity in erythrocytes using Lactobacillus leichmannii. The results are shown for age, sex, and blood group in normal subjects, and before, during, and after therapy in vitamin B(12) deficiency anaemia. The normal range is 85-225 pg/ml (mean = 155 +/- 35 pg/ml). Raised levels were found in the newborn, and subnormal levels in subje...

Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency.

BACKGROUND Vitamin B12 deficiency is common, and the incidence increases with age. Most people with vitamin B12 deficiency are treated in primary care with intramuscular (IM) vitamin B12. Doctors may not be prescribing oral vitamin B12 formulations because they may be unaware of this option or have concerns regarding its effectiveness. OBJECTIVES To assess the effects of oral vitamin B12 vers...

Detection of vitamin B12 deficiency in older people by measuring vitamin B12 or the active fraction of vitamin B12, holotranscobalamin.

BACKGROUND Impaired vitamin B(12) function and decreased vitamin B(12) status have been associated with neurological and cognitive impairment. Current assays analyze total vitamin B(12) concentration, only a small percentage of which is metabolically active. Concentrations of this active component, carried on holotranscobalamin (holoTC), may be of greater relevance than total vitamin B(12). M...