However, under the conditions of reduced or total loss of activity of homocystine
metabolizing enzyme due to mutation in corresponding gene, this metabolic balance is disturbed resulting into hyperhomocystenimia.
We have also reported (17) selective and highly sensitive HRS assay for mercury (II) recognition in 5 ppb level in aqueous solution using gold nanopartilces modified with mercaptopropionic acid, homocystine
and 2,6-pyridinedicarboxylic acid.
Homocysteine and homocystine
, in large quantities, may be harmful.
Folate administration, although proven to reduce homocystine
levels, has not currently been shown to reduce levels of any cardiovascular disease.
The most recent association has been with the concentration of an amino acid called homocystine
in the blood.
Free Total Homocystine
homocysteine NBS LD NBS LD Number of samples 234 25 104 8 Mean 15.1 15.7 91.1 88.5 Median 9.5 5 79 71.5 Range 0-90 0-100 5-269 9-202 P value P = 0.917 P = 0.933 Methionine Cystine NBS LD NBS LD Number of samples 237 25 223 24 Mean 72.6 119.6 39 43 Median 62.5 99.2 31.5 35.3 Range 3-600 10-324 4-180 3-57 P value P = 0.165 P = 0.660 TABLE 2: Percentage of patients meeting the Great Ormond Street (GOS) and Ross and Genetic Metabolic Dietitians International (GMDI) protein recommendations.
Concentrations of 6 other amino acids including alloisoleucine, homocystine
, cystathionine, cystine, argininosuccinate, [alpha]-aminoadipic acid, were not detectable (< 1 [micro]mol/L) in blood spot extracts.
A previously unrecognized risk factor for stroke, which is prevalent and modifiable, is elevated plasma homocystine
. (5) Hyperhomocysteinemia appears to act independently of other risk factors.
A hypercoagulable workup (protein C, protein S, factor II mutation, antithrombin III level, lupus anticoagulant, MTHFR mutation, cryoglobulin, homocystine
, cardiolipin antibody, lipoprotein (a), beta-2 glycoprotein) showed abnormality of Factor V Leiden with heterozygousity for R506Q polymorphism.
(For cystine and homocystine
, quantitative, see 82131, 82136, 82139)
The pathways were altered by feeding either methionine or homocystine
(H-H) in conjunction with either folic acid (FA) or choline deficiency.
We also investigated for prothrombotic states, like Anti thrombin III concentrations, Homocystine
levels, Factor VIII, Factor V Leiden, albumin, fibrinogen, and, platelet count, platelet aggregation, and bleeding time were normal.