Pernicious anemia has recently been recognized as a risk factor for osteoporosis and fractures. Although vitamin B12 is important for osteoblast function, the effect of vitamin B12 replacement in states of vitamin B12 deficiency on bone density and fracture incidence is not known. We report 2-year follow-up data from a patient with severe osteoporosis, multiple vertebral compression fractures, ...

In 2008, clinicians performing routine medical examinations in the United States reported high rates of hematologic and neurologic disorders caused by vitamin B12 deficiency in resettled Bhutanese refugees. To confirm this finding, CDC screened Bhutanese refugees' serum samples for vitamin B12 levels and found vitamin B12 deficiency in 64% (n = 99) of samples obtained before departure and 27% (...

Maternal vitamin B12 deficiency during pregnancy is an independent risk factor for neural tube defects and other neurological problems in infants. We determined the vitamin B12 status of 143 pregnant women in Nigeria representing all trimesters who presented to an antenatal clinic in Jos, Nigeria, using holotranscobalamin II levels (holoTCII), which is a measure of the vitamin B12 that is avail...

Vitamin B12 is an essential vitamin that is widely used in medical and food industries. Vitamin B12 biosynthesis is confined to few bacteria and archaea, and as such its production relies on microbial fermentation. Rational strain engineering is dependent on efficient genetic tools and a detailed knowledge of metabolic pathways, regulation of which can be applied to improve product yield. Recen...

The cysG gene of Salmonella typhimurium is involved in synthesis of both cobalamin (B12) and siroheme (a cofactor required for SO3(2-) and NO2(2-) reductases). The failure to reduce SO3(2-) leads to cysteine auxotrophy, for which the enzyme is named. Although Escherichia coli does not synthesize B12 de novo, it possesses a very similar CysG enzyme which has been shown to catalyze two methylatio...

Very old adults are at increased risk of folate and vitamin B12 deficiencies due to reduced food intake and gastrointestinal absorption. The main aim was to determine the association between folate and vitamin B12 intake from total diets and food groups, and status. Folate or vitamin B12 intakes (2 × 24 h multiple pass recalls) and red blood cell (RBC) folate or plasma vitamin B12 (chemilumines...

The human monoclonal antibody b12 recognizes a conserved epitope on gp120 that overlaps the CD4 binding site. b12 has neutralizing activity against diverse human immunodeficiency virus type 1 (HIV-1) strains. However, we recently reported that b12 sensitivity of HIV-1 envelopes amplified from patient tissues without culture varied considerably. For two subjects, there was clear modulation of b1...

Background Metformin is the most common oral hypoglycemic used and associated with certain abnormalities. The objective was to evaluate and define the occurrence and bases of vitamin B12 deficiency amongst patients on Metformin for diabetes mellitus type II. Methods A cross-sectional study was conducted on 209 patients having diabetes type II between January-December 2016. The patients aged > 4...

Many children in low- and middle-income countries may have inadequate intake of vitamin B12 and folate; data confirming these inadequacies are limited. We used biochemical, demographic, behavioral and anthropometric data to describe the folate and vitamin B12 concentrations among six- to 23-month-old Nepalese children. Vitamin B12 (serum B12 < 150 pmol/L) and folate deficiencies (red blood cell...

We investigated the influence of varying cobalt (Co) and B12 concentrations to growth and nitrogen fixation of Trichodesmium, a major diazotroph in the tropical and subtropical oligotrophic ocean. Here we show that sufficient inorganic Co, 20 pmol L(-1), sustains the growth of Trichodesmium either with or without an additional B12 supply. We also found that in these culture conditions, nitrogen...