Determination of cobalamins
in biological material.
In these circumstances, it is possible that the NO might diminish the enzyme cofactor abilities of cobalamins
and produce a functional vitamin [B.
This hybrid method allows scientists to quickly detect and measure levels of specific individual cobalamins
in food and supplement samples.
The newer technique for quantifying cobalamins
uses one of two separation methods.
) deficiency is important because cobalamin
is required for biosynthesis of DNA, RNA, and protein.
deficiency can have protean morbid effects on health.
If genetic factors were the only regulators of the HC concentration, the physician could decide that the low concentration of cobalamins
reflected an inherited low HC.
5) 28 MMA, [micro]mol/L 240 (71-563) 38 Cobalamins
, pmol/L 188 (81-770) 46 Total TC, pmol/L 1002 (544-1584) 22 HoloTC, pmol/L 53 (24-180) 55 TC saturation, fraction 0.
HoIoTC calibrators (Axis-Shield) were prepared gravimetrically from a stock solution of recombinant holoTC saturated with cobalamins
12] saturated transcobalamin (holo-TC)(4) or total cobalamin
after oral ingestion of vitamin [B.
No detectable leakage of cobalamins
from the beads was observed as judged from measurement of cobalamins
in the supernatant of 250 [micro]L of stock solution of the washed beads redisolved in 250 [micro]L of buffer (<33 pmol/L cobalamin
Blood was collected into tubes without anticoagulants for measurement of P-MMA and plasma creatinine, into heparin fluoride-containing tubes for measurement of P-tHcy, and into EDTA-containing tubes for measurement of plasma cobalamins
, blood hemoglobin, erythrocyte mean cell volume, erythrocyte folate, platelet count, and white cell count.
Thus, measurement of plasma cobalamins
is at the same time a measure for the sum of haptocorrin and transcobalamin saturated with cobalamin
Methionine synthase catalyzes the transfer of the methyl group of 5-methyltetrahydrofolate to homocysteine via a methylcobalamin intermediate with cycling of cobalamin
between the +1 valency state cobalamin
and the +3 valency state cobalamin
12] from the liver, or decreased clearance of cobalamin
from plasma (12).