Determination of homocysteine and other low-molecular-weight amino thiols in blood plasma

The relevance of the development and the improvement of methods for the determination of metabolites (biomarkers) of toxic substances in biological fluids (blood, urine, etc.) is associated with the need to establish facts of humans and animals exposure to toxic chemicals. The need for such analysis arises within the framework of monitoring of the compliance with the provisions of the Chemical Weapons Convention (CWC), when conducting investigations into the alleged use of chemical agents, as well as within the framework of the official proficiency tests carried out by the Organization for the Prohibition of Chemical Weapons (OPCW). Nowadays there exists the problem of the determination of low-molecular-weight mustard gas biomarkers in biological samples with the use of gas chromatography methods with mass-selective detection. The low-molecular-weight biomarkers of sulfur mustard (SM) are thiodiglycol, oxides and sulfoxides. The identification and quantitative assessment of SM markers in blood and urine is carried out according to the methods, based on the displacement of thiodiglycol and its derivatives from protein conjugates with titanium trichloride, solid-phase extraction, concentration in ethyl acetate solution, derivatization with pentafluorobenzoyl chloride, heptafluorobutyrylimidazole, heptafluorobutyric acid anhydride or chloride, subsequent stripping of the derivative into the appropriate solvent and GH-MS analysis (chemical ionization technique with methane as a reagent gas with the registration of negative ions). After the sample preparation, the limits of detection of the minimum values of ultra-low concentrations of the analyzed biomarkers of SM in urine and blood plasma were determined. After the chromatographic analysis, the corresponding graphs of indicators have been constructed, based on the concentrations of biomarkers in urine and blood plasma. Later on they have been used for the elaboration of the methods for the determination of SM biomarkers in human urine and blood.

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The value of low-molecular-weight DNA of blood plasma in the diagnostic of the patological processes of different genesis

Biomeditsinskaya Khimiya ◽

10.18097/pbmc20135903358 ◽

2013 ◽

Vol 59 (3) ◽

pp. 358-373 ◽

Cited By ~ 2

Author(s):

I.N. Vasilyeva ◽

V.N. Zinkin

Keyword(s):

Molecular Weight ◽

Blood Plasma ◽

Low Frequency ◽

The Body ◽

Chronic Obstructive ◽

Low Molecular Weight ◽

Frequency Noise ◽

Obstructive Pulmonary Disease ◽

Blood Concentrations ◽

In Blood Plasma

The low-molecular-weight DNA appears in blood plasma of irradiated rats, and its content correlates directly with the irradiation dose. Cloning has shown, that enrichment of low-molecular-weight DNA with G+C content and features of its nucleotide sequences point to its ability to form rather stable nucleosomes. DNA obtained after irradiation of rats with principally different doses 8 and 100 Gy differed not only quantitatively, but also by content of the dinucleotides CpG and CpT; this suggests their origin from different sites of genome. For the first time it has been shown that exposure to low-frequency noise results in an increase of the contents of blood plasma low-molecular-weight DNA. In stroke patients blood concentrations of this DNA increased 3 days after the beginning of the acute period, and dynamics of its excretion differs in ischemic and hemorrhagic forms; in the case of ischemia low-molecular-weight DNA appears in cerebrospinal fluid. The chronic obstructive pulmonary disease in the state of remission is characterized by the decline of the level of low-molecular-weight DNA in the blood plasma unlike in the case of the chronic nonobstructive bronchitis. The clear dependence between formation and special features of the low-molecular-weight DNA fraction in blood plasma makes it possible to consider the low-molecular fraction as an universal index of apoptosis, which allows to distinguish basically different conditions of the body.

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