We have examined the prevalence of the C677T and A1298C single nucleotide polymorphisms (SNPs) in the methylenetetrahydrofolate reductase (MTHFR) gene in healthy Tamilians and in patients with acute myocardial infarction and related this polymorphism to plasma homocysteine concentrations, serum folate, serum cobalamin and riboflavin status. The SNPs in the MTHFR gene were determined by polymera...

Because cobalamin deficiency is routinely treated with parenteral cobalamin, we investigated the efficacy of oral therapy. We randomly assigned 38 newly diagnosed cobalamin deficient patients to receive cyanocobalamin as either 1 mg intramuscularly on days 1, 3, 7, 10, 14, 21, 30, 60, and 90 or 2 mg orally on a daily basis for 120 days. Therapeutic effectiveness was evaluated by measuring hemat...

BACKGROUND Vitamin B₁₂ deficiency is common among the elderly, and early detection is clinically important. However, clinical signs and symptoms have limited diagnostic accuracy and there is no accepted reference test method. METHODS In elderly subjects (n = 700; age range 63-97 years), we investigated the ability of serum cobalamin, holotranscobalamin (holoTC), total homocysteine (tHcy), met...

PURPOSE The aim of the study was to investigate whether pelvic radiotherapy for rectal cancer had a negative impact on cobalamin status. METHODS AND MATERIALS Consecutive patients receiving pelvic radiotherapy (50 Gy) for rectal cancer were evaluated prospectively (n = 54). Serum cobalamin, holotranscobalamin (holoTC), methylmalonic acid (MMA), and total homocysteine (tHcy) were measured at s...

Vitamin B12 (cobalamin) deficiency is prevalent worldwide and causes megaloblastic anemia and neurologic deficits. While the anemia can be treated, the neurologic deficits can become refractive to treatment as the disease progresses. Therefore, timely intervention is critical for a favorable outcome. Moreover, the metabolic basis for the neuro-pathologic changes and the role of cobalamin defici...

BACKGROUND Anemia is a major public health problem among children under 5 years of age in India. Cobalamin and folate deficiencies play an important role in the etiology of anemia. This study was done to assess the prevalence of cobalamin and folate deficiencies among children in the age group of 12-59 months. METHODS A community-based cross-sectional study was conducted. A total of 470 child...

ATP:co(I)rrinoid adenosyltransferases (ACATs) are enzymes that catalyze the formation of adenosylcobalamin (AdoCbl, coenzyme B(12)) from cobalamin and ATP. There are three families of ACATs, namely, CobA, EutT, and PduO. In Salmonella enterica, CobA is the housekeeping enzyme that is required for de novo AdoCbl synthesis and for salvaging incomplete precursors and cobalamin from the environment...

Hypothyroidism may result in accelerated atherosclerosis. Hyperhomocysteinaemia is an independent risk factor for premature atherosclerotic vascular disease. The aim of the present study was to assess plasma total homocysteine (tHcy), folate and cobalamin concentrations in hypothyroid patients before and after treatment. Thirty-one hypothyroid and thirty health young women were studied. The hyp...

The distribution of cobalamin cofactors was investigated in the livers and tumors of rats bearing transplanted Morris 7777 or 7800 hepatomas, in the livers of rats treated with the hepatocarcinogen diethylnitrosamine, and in normal rats. There was a significant increase in the proportion of methylcobalamin both in livers and tumors from rat bearing the hepatomas 7777 and 7800 compared to the pr...

We describe a radioassay for cobalamin (vitamin B12) in human serum or plasma that requires no boiling or other pretreatment of the sample. Normal chicken serum covalently coupled to magnetizable particles is used as the binding agent. The assay is performed at pH 12.9, at which pH all cobalamin in human serum is released from its binding proteins, whereas the binding agent maintains a high aff...