The possibility of diagnosing intrauterine infection by the content of nitrite and non-thiolate nitroso compounds in maternal blood plasma

The aim of the study is to develop a method for early diagnosis of intrauterine infection (IUI). A study of markers of inflammation in the venous blood of 60 pregnant women was conducted. The study was followed by a retrospective assessment of the outcomes of pregnancies and childbirth. Of these, 33 patients with a gestation period of more than 37 weeks (full-term pregnancy) and, accordingly, 27 patients from whom the blood sample was taken at a period of less than 37 weeks - patients with the threat of premature birth (PB). PB is the main factor contributing to the development of IUI. 27 patients were diagnosed with premature rupture of the membranes (PROM). Of these, 15 are with the threat of PB. 8 of them had a diagnosed IUI. In all cases of diagnosed PROM, including those with IUI, the concentration of nitrite and nontiolate nitroso compounds (NO2-+RNO) in the mother's blood plasma was 2.3±1.2 µM, while normally it does not exceed 0.1 µM (p<0.001). Regardless of the duration of pregnancy. The use of antibiotics in the case of PROM contributed to the normalization of the concentration (NO2-+RNO). Therefore, increasing of this indicator is result of bacterial infection. Indications of other markers of inflammation: the number of leukocytes in venous blood and in a smear of vaginal contents, the level of C-RB did not significantly change in both PROM and IUI (p>0.1). Since the concentration index (NO2-+RNO) increased in almost all cases of PREM, unlike all other clinical and biochemical indicators used in modern medicine, there is an obvious sense of its use for the current monitoring of the health of pregnant women. But it is still impossible to say unequivocally about the possibility of monitoring the fetal health by concentration (NO2-+RNO) in the mother's blood.

[Possibilities for the diagnosis of inflammatory reaction in ischemic stroke]

AIM

To study diagnostic possibilities for determining the content of nitrite and N-nitroso compounds (NO₂^-+RNNO) in blood plasma and cerebrospinal fluid (CSF) in patients with acute ischemic stroke (IS).

MATERIAL AND METHODS

Twenty-four patients with IS were examined. The content of NO oxidation products was determined in venous blood and CSF by using an enzyme sensor based on the unique property of nitrite (NO₂^-), N-nitroso compounds (RNNO), S-nitrosothiols and dinitrosyl iron complexes to inhibit the enzyme catalase in the presence of halide ions. The study was conducted on the 1st day of IS.

RESULTS AND CONCLUSION

CSF in patients with IS contained nitrite and N-nitroso compounds (NO₂^-+RNNO) in concentrations ranging from 0.4 to 2.0 µm. The relationship between the size of IS and the concentration of NO₂^-+RNNO in CSF was shown. It was 1.01±0.13 µm in patients with medium IS and 0.71±0.07 µm in patients with small IS (U-criterion 16.5; p<0.05). There was no correlation between the severity of neurological deficit at the time of hospitalization and discharge from the hospital and the content of NO₂^-+RNNO in CSF (r=0.134; p>0.5; r=0.155; p>0.5, respectively). Plasma NO₂^-+RNNO levels were not associated with the presence and size of IS though they were elevated in patients with inflammatory complications. In conclusion, NO₂^-+RNNO can be considered as a marker of inflammation in patients with IS. Their presence in CSF reflects the extent of brain damage, but not the presence of concomitant inflammatory diseases.

Selectivity in Physiological Action of Nitric Oxide: A Hypothetical Mechanism

The study showed that dinitrosyl iron complex (NO)₂Fe(RS)₂ containing the thiolate ligands, which is the basic physiological donor of NO, can transfer NO to other molecule only at the moment of rearrangement. This rearrangement can occur during interaction of the complex with more effective iron chelators than the thiolate ligands. In the absence of NO trap, a new complex is formed with a new ligand. NO transfer to a trap can also occur under the action of the agents such as mercury salts or ROS, which interact with the thiolate ligands. Probably, the ligands in the dinitrosyl iron complexes are the structures responsible for interaction of these complexes with physiological targets and for specificity and effectiveness of this interaction.

Enzymatic Sensor Detects Some Forms of Nitric Oxide Donors Undetectable by Other Methods in Living Tissues

Studies with the use of highly sensitive enzymatic sensor have shown the presence of various forms of nitrosyl iron complexes, including those undetectable by other methods, in living tissues. All these complexes are long-living compounds and constitute the major part of nitroso compounds in the blood, muscles, liquor, and amniotic fluid.