[The functional properties and oxidative modification of plasma and neutrophil proteins in community-acquired pneumonia].

The functional properties of neutrophils (the activity of myeloperoxidase and the production of hydroxyl radical) were studied in community-acquired pneumonia (CAP) predominantly with the alveolar and interstitial types of lung parenchymal infiltration. Protein oxidative modification was estimated from the content of protein carbonyl derivatives in neutrophilic leukocytes and plasma and from the plasma concentration of bityrosine and oxidized tryptophan in patients with CAP. The production of hydroxyl radical and the activity of myeloperoxidase in the neutrophils of patients with CAP were increased and did not depend on the type of lung tissue infiltration. The development of oxidative stress in CAP was accompanied by the substantiation activation of protein oxidative modification processes in the neutrophilic leukocytes and plasma.

Role of thiol-disulfide system in mechanisms of functional changes in neutrophils under conditions of oxidative stress.

We studied the state of the thiol-disulfide system (contents of reduced and oxidized glutathione, their ratio, and concentrations of protein SH-groups and protein-bound glutathione) and functional properties of neutrophils (production of hydroxyl radicals, IL-8, and TNF-α and myeloperoxidase activity) from healthy donors under conditions of oxidative stress in vitro induced by H(2)O(2)in a final concentration of 200 µM and from patients with community-acquired pneumonia. We evaluated the role of reduced and protein-bound glutathione in the regulation of functional state of blood neutrophils from patients with community-acquired pneumonia and during oxidative stress in vitro under conditions cell incubation with N-ethylmaleimide or 1,4-dithioerythritolsulfhydryl, the blocker and protector of sulfhydryl groups, respectively.

Regulatory role of nitric oxide in neutrophil apoptosis.

Apoptosis of blood neutrophils from healthy donors was studied under conditions of cell culturing with different concentrations of H(2)O(2), selective NO synthase inhibitor, and inductor of NO synthesis (L-arginine). In vitro incubation of neutrophilic leukocytes with 5 mM H(2)O(2) led to activation of the apoptotic program in neutrophils, which was seen from increased content of Bax protein in the cells and increased number of apoptotic cells in the culture. Increased content of annexin-positive cells after incubation of neutrophil culture with NO synthase inhibitor suggests involvement of NO in the regulation of neutrophil apoptosis under conditions of oxidative stress, while L-arginine prevented H(2)O(2)-induced programmed cell death.

[Extrahospital pneumonias: the clinico-scintigraphic characterization and oxidative balance of cells].

Ventilation-perfusion pulmonary scintigraphy was carried out in 30 patients with a verified diagnosis of extra-hospital pneumonia (EHP) and 10 healthy subjects; ventilation-perfusion ratio (V/Q), apex-basis ventilation and perfusion gradient, and the condition of alveolar-capillary permeability (ACP) were analyzed. Clinical symptoms during the debut of EHP were more pronounced in patients with an alveolar type of pulmonary infiltrate (PI) vs. patients with interstitial one: they had pulmonary infiltration syndrome, pleural pain, tachypnoe, tachycardia, a fever of higher than 38 degrees C, and leucocytosis more often. During the acute period of EHP, elevated lipid peroxidation in the erythrocyte membrane as well as a decrease in the content of reduced glutathione and the activity of superoxide dismutase and catalase in erythrocytes did not depend on the type of PI. In EHP, independently of PI type, the study revealed an increase in V/Q of higher than 1.0 on the side of lesion and bilateral (including the healthy side) increase in ACP for radioactive aerosol.

Hepatoprotective and antioxidant activity of meadowsweet extract during experimental toxic hepatitis.

The extract of meadowsweet aerial parts exhibits hepatoprotective and antioxidant activity during experimental toxic CCl(4) hepatitis. This extract improved liver function. Meadowsweet extract in 70% ethanol (100 mg/kg) was most potent and exhibited low toxicity. By several parameters the effectiveness of this extract surpassed that of Carsil.

[Impaired oxidative metabolism in acute inflammatory diseases].

The specific features of lipid peroxidation (LPO) and the activity of enzymatic antioxidants in the plasma and red blood cells of patients with acute appendicitis, phlegmons, and abscesses located in the soft tissues of the shin, hip, buttocks, shoulder, and forearm were comprehensively evaluated. In these diseases, the signs of evolving oxidative stress were revealed irrespective of the site of an acute inflammatory focus. Excess accumulation of LPO products was recorded with the inhibition of antioxidative defense components, including erythrocytic glutathione-dependent enzymes. The manifestations of antioxidant deficiency were accompanied by a reciprocal increase in the concentration of the antioxidative protein ceruloplasmin and increased with more severe inflammation. The signs of imbalance in the prooxidant/antioxidant defense system slightly normalized at discharge during clinical convalescence.