[Benefits of antioxidant agents' use for dental filling consequent to the endo-bleaching].

Efficacy of antioxidant agents' use after dental endo bleaching was studied in clinical trial. The study enrolled 169 patients, ranging age 16 to 60 years in age. The patients were randomized into 2 groups: control (63) and trial (106). In patients of the control group tooth cavity was left open after endo bleaching, and was filled only after 7 days. In patients of the trial group antioxidant agent was administered into the dental tissues consequently to the endo bleaching, and the cavity was filled immediately. Assessment of the immediate and distant effects revealed unwanted results of postponed dental filling (control group) in terms of tooth color stability and forming micro cracks. Results of antioxidant use and immediate dental filling after endo bleaching have proven our earlier experimental studies on benefits of antioxidant use to be right. Based on the results of our clinical study we can recommend use of antioxidant after endo bleaching to achieve successful dental fillings in clinical practice.

Role of free nitrogen and oxygen radicals in the pathogenesis of lipopolysaccharide-induced endotoxemia.

We studied molecular mechanisms of changes in oxidative metabolism under conditions of experimental lipopolysaccharide-induced endotoxemia. Generation of reactive nitrogen and oxygen species in mice increased 18 h after treatment with lipopolysaccharide. These changes contributed to inactivation of enzymes and enzyme complexes (ribonucleotide reductase, NADH-ubiquinone oxidoreductase, and cytochrome c oxidase), dysfunction of the mitochondrial electron transport chain, and development of oxidative stress. Plaferon LB protected mice from the toxic effect of lipopolysaccharide.

[The role of oxidative metabolism in pathogenesis of hyperbilirubinemia in infants].

The aim of the study was the investigation of free radical oxidation intensity in blood of newborn infants with hyperbilirubinemia. In infants blood the bilirubin, free nitric oxide, lipoperoxide radicals Fe(2+)-ions, methemoglobin, oxy- and desoxy hemoglobin content, erythrocytes deformability and resistance were studied. Results of the study testify the intensive generation of free nitric oxide, release of ferritin-free ferrous (Fe(2+)), intensification of lipoperoxidation, decrease of red blood cells resistance, and accumulation of methemoglobin in blood of newborn infants with hyperbilirubinemia. The low content of nitric oxide in blood is due to its oxidative transformation to peroxynitrite. NOO(-)-inducible hemolysis of erythrocytes is one of promoters of hyperbilirubinemia in infants. It was concluded, that the reason of infants hyperbilirubinemia is intensification of oxidative stress, formation of excessive nitric oxide, enhancing of red blood cells haemolysis and it promotes disturbance of erythrocytes membrane, decrease of their resistance and deformability, intensification of haemolysis and extrication of redox-active iron.

[Plaferon LB in prevention of radiation-induced changes in lipid metabolism indices and erythrocyte deformability rate].

Oxidative damage of biological membranes plays critical role in the process of radiation-induced damages in tissues and cells. It involves reactive oxygen species generated under ionizing radiation. Development of radiation-induced oxidative stress facilitates the intensification of lipid peroxidation and fatty acid reorganization, which, in its turn, results in decreased lipid matrix fluidity, changes in biophysical properties of membranes, increased rigidity of membrane lipid-protein surface. Radiation-induced damage of cellular and subcellular membrane structures results in cellular metabolism disorder, which facilitates farther dysfunction of tissues and changes in homeostasis of whole organism. Hence, the search for effective protection is of actual interest of contemporary radiology. Our study aimed to determine membrane protective properties of Plaferon LB under radiation. On the basis of obtained results we can conclude that intensification of free radical oxidation, accompanying radiation damage, facilitates the activation of lipolysis in a body and functional and structural disorders of erythrocytes revealed by lowered deformability of erythrocytes and accumulation of methaemoglobin. Both vitamin C and Plaferon LB were found ineffective for correction of lipid metabolism at early stage of post radiation damage; although facilitating a decrease in oxidation intensity in blood, they provided retention of erythrocyte deformability and thereby, partial retention of rheological properties of blood. It should be mentioned that in contrast with vitamin C, Plaferon LB, apart from its ability to restrict reactive oxygen formation, revealed ability to stabilize erythrocyte membranes and thereby to prevent hemolysis.

[Age related changes of physical-chemical parameters of erythrocytes].

The aim of our study was to investigate age related changes of physical-chemical parameters of erythrocytes. It is known that insufficiency of erythrocytes antioxidant defence system in newborns is a keystone of peculiarities manifested in homeostasis among this group. The excess volume of reactive oxygen determines disorders related to the functioning of cation channels that are represented by decrease of K(+) ions, moderate hydration of erythrocytes and may cause accumulation of intraerythrocyte calcium. Excessive calcium may also cause activation of Ca(2+)-dependent erythrocytes' NOS and increase of nitric oxide content in newborns' erythrocytes. However, in spite of high NO content, the insufficiency of antioxidant system is conductive to intensive formation of methaemoglobin in newborns' blood. The other cause of intensive haemolysis of erythrocytes in this age group may be also the activation of Ca(2+)-dependent mechanism, which contributes to the exposition of phosphatidilserin on the surface of the erythrocyte's membrane and elimination of erythrocytes by macrophages. The increasing activity of antioxidant enzymes among aged persons seems to be a compensatory mechanism against excessively reactive oxygen in old age and this process ensures maintenance of intensity of hemolysis within the physiological frames.

[Use of lectin for detection of changes of erythrocytic osmotic resistance and deformity in acute advanced peritonitis]. / Primenenie lektina dlia vyiavleniia izmenenii osmorezistentnosti i stepeni deformatsii éritrotsitov pri ostrom rasprostranennom peritonite.

Thirty-one patients with acute general peritonitis were studied. Lectin (LPM) demonstrated an additional peak on kinetic curves of erythrocytic osmolysis in patients with acute general peritonitis. Deformity of erythrocytes had a tendency to decrease (p > 0.05), but in the presence of LPM this difference increased sharply (p < 0.001). On day 7 after surgery in case of a favorable outcome the peak decreased or disappeared, deformity of erythrocytes also disappeared. It is important for diagnosis and prognosis.