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Biomedical subjects

L V Koval'chuk

Publications and source records attributed to L V Koval'chuk.

At least 19 recordsLinked to original sources

[A comprehensive study of the mechanisms of the development of chronic inflammation in periodontitis].

Bacteriological and cytological analysis of the saliva, dental plaques, and gingival fluid was carried out in 48 patients with periodontitis and 25 donors. The concentrations of proinflammatory cytokines IL-1 and TNF-alpha were increased, the levels of anti-inflammatory cytokines IL-4 and TFR beta-1 were decreased, and MIF production was suppressed in the patients in comparison with donors. Important theoretical and practical recommendations are offered.

Adult↗

[Role and significance of structural, metabolic and functional disorders of mononuclear phagocytes in pathogenesis of caseous pneumonia].

Comprehensive clinical, X-ray, cytochemical, morphological, biochemical, and immunological studies of 14 patients with caseous pneumonia have provided evidence that significant structural, metabolic, and functional disorders of mononuclear phagocytes (MNP) play a leading role in the pathogenesis of acute tuberculosis. Structural and metabolic disorders of macrophages and monocytes in patients with caseous pneumonia result from impaired mitochondrial oxidation and glycolysis, aggregation and latinization of the membranes of lysosomes, release of their contents into the cytosol with damages to intracellular structures and the cellular membrane itself. This is also suggested by a drastic rise in the production of prostaglandins E2 and F2 alpha, prostaglandins E2 in particular, in the supernatants of cultured monocytes (100 nM). This is determined as the membrane-damaging effect of MNP due to the toxic action of rapidly multiplying mycobacterial population not only in the lung, but even in blood. MNP structural and metabolic disturbances are an equivalent to their lowered functional activity, as evidenced by a considerable deficiency of synthesis of intracellular and secretory pools of interleukin I and by a fall in their migrational and adhesive activities, two thirds of macrophages having signs of dystrophy and cytolysis. On entering the specific inflammatory area of the lung, these cells abundantly disintegrate. Their destruction leads to the elaboration of enzymes, prostaglandins, and other biologically active agents, which promotes the occurrence of extensive caseously destructive changes and creates conditions for rapid multiplication of mycobacteria.

Acute Disease↗

[The activation processes of T-lymphocytes and their regulatory subpopulations in patients with pulmonary tuberculosis].

Immunophenotyping of lymphocytes by direct double-color immunofluorescence, investigation of metabolic activity of succinate dehydrogenase, alpha-glycerophosphate dehydrogenase, glucose-6-phosphate dehydrogenase, NAD- and NADP-diaphorases were performed in 77 tuberculous patients and 50 healthy donors. Activation of T-lymphocytes and their regulatory subpopulations is shown to depend on the extension of lung infiltration. At the same time, there were marked disorders in intracellular metabolism of peripheral blood lymphocytes. Close correlation exists between the activity of lymphocytic energy enzymes and the degree of expression on lymphocytes of receptors to interleukin-2, transferrin and HLA-DR-molecules. Cytochemical reactions for evaluation of blood lymphocyte energetic enzymes activity may be used in clinical practice for characterization of activation of T-lymphocytes and their regulatory subpopulations.

Adult↗

[Increased apoptosis of immunocompetent cells as a possible mechanism in the development of immunodeficiency in patients with acutely progressive tuberculosis].

The formation of immunodeficiency whose likely mechanism is apoptosis of some immunocompetent cells was studied in 35 patients with caseous pneumonia. The leading clinical sign of apoptosis in acutely progressive tuberculosis is significant lymphopenia (4-10%). Immunological studies indicated a substantial reduction in the count of T lymphocytes and their regulatory subpopulations of different phenotypes. In vitro mitogenic induction causes a decline of activated CD3+, CD4+, and CD8+ cells on the average by 10-40%, a decrease in the proliferative and synthetic functions, as compared with those in patients with infiltrative tuberculosis of the lung and healthy donors. Cytochemical findings in the same patients show that half the lymphocytes in the blood samples from patients with caseous pneumonia has profound intracellular metabolic disturbances. These cells are unavailable and undergo apoptosis, which determines immunodeficiency in patients with acutely progressive tuberculosis.

Acute Disease↗

[Cellular and intracellular markers of lymphocyte activation in patients with infiltrative pulmonary tuberculosis].

The authors investigated markers of activation of CD25-, CD71- and HLD-DR molecules on CD3+, CD4+ and CD8+ lymphocytes simultaneously with cytochemical activity of the main energetic and synthetic enzymes in 34 patients with new-onset infiltrative tuberculosis of the lungs and in 30 healthy controls. It was found that reduced number of effector and regulatory lymphocyte subpopulations was recorded only in patients with advanced infiltrative tuberculosis in line with a sharp decline in enzymatic and functional activity of immunocompetent cells. In local infiltrative tuberculosis impairment of activation processes occurs only at intracellular level in time of energy metabolism shift to predominant glycolysis, this allowing lymphocytes to persist functionally active. A close relationship is shown between glycolytic enzymes and activation of CD3+ cells and their subpopulations. Basing on the above findings, one may refer the above enzymes to intracellular activation markers of lymphocytes.

Adult↗

[A comparative study of the expression of activation markers on T-lymphocyte subpopulations in different forms of bronchial asthma].

In this study we investigated a phenotype of intact and PHA-stimulated T-lymphocytes from peripheral blood of patients with allergic and nonallergic asthma. Expression of the activation markers (CD25, CD71, HLA-DR) on subsets of T-lymphocytes (CD4+ and CD8+) was determined using double-colour flow cytometry. It was found that nonallergic patients had increased percentages of CD4+CD25+, CD8+CD25+, CD4+HLA-DR+, CD8+HLA-DR+ cells. Allergic patients had a significant increase of CD4+CD25+ cells only. To examine functional significance of these changes mononuclear cells were cultivated with PHA in vitro. Thus, our findings improve our knowledge about asthma pathogenesis and create the grounds for pathogenetically validated immunocorrection.

Adult↗

[The characteristics of the immune status of patients with Alzheimer's disease].

Disorders seen in patients with Alzheimer's disease are also related to the pathology of immunity. In order to study it in a more detailed manner, some immunity parameters were examined in 30 patients with Alzheimer's disease, 15 patients with Huntington's chorea which may have similar mechanisms of immunologic defects, and 15 healthy donors. A study was also made of the capacity of peripheral blood lymphocytes to respond to polyclonal mitogens in blast transformation test and according to the production of immunoglobulins in vitro. The subpopulation composition of these cells was investigated as well. A significant rise of the count of C 8+ lymphocytes, depression of proliferative response, low spontaneous and high Phytolacca mitogen-stimulated immunoglobulin production have been revealed. The changes recorded in Huntington's chorea had the same nature of development. The disorders revealed allow a conclusion about an important role that may be played by the immune system in these degenerative diseases of the brain.

Alzheimer Disease↗

[The interpretation of laboratory parameters in evaluating the immune status of man].

At least 3 physiologic parameters appear to be useful for the assessment of the immunity status of a patient. These parameters are as follows: immunocyte ability to activation, proliferation, and differentiation; these characteristics may be directly examined with the use of novel products of immunobiotechnology. The suggested approach essentially simplifies interpretation of the findings obtained in studies of human immunity system. Besides lymphocytes, special attention is paid to immunoregulatory monocytes, macrophages, and granulocytes. Since these cells are known to secrete quite a number of mediators, an imbalance of their production and reception may contribute to the pathogenesis of many a disease.

Humans↗

Priming of phagocytes by cytokines and water-soluble products of lipid peroxidation.

It is well known that during certain pathological processes phagocytes acquire the ability to generate activated oxygen species during phagocytosis. The priming of phagocytes by cytokines and water-soluble products of lipid peroxidation (LPO) is described. Preincubation of human polymorphonuclear leukocytes (PMNL) with the water-soluble products of LPO or oxidised liposomes for 15-20 min at 37 degrees C enhanced their functional activity when they were stimulated by opsonised zymosan or latex particles. There was a 2-3-fold increase in luminol-dependent chemiluminescence response of cells stimulated in this way, and an increase in Fc-receptor expression on the PMNL surface. An endogenous cytokine alone did not activate the phagocytes for an oxidative burst response, but preincubation of murine peritoneal macrophages (MP) and human PMNL with cytokines (molecular mass 20-30 kDa) for 3-48 h at 37 degrees C enhanced the cell chemiluminescence response to opsonised zymosan by a factor of 5-9 for MP and a factor of 2-3 for PMNL. Treatment of phagocytes with the cytokine complex also increased other effector functions of the phagocytes such as tumouricidal activity, phagocytosis, secretion of interleukin-1, and antiparasitic activity. The protein synthesis inhibitor cycloheximide abolished cytokine-induced priming of MP (but not of PMNL). The mechanisms of short-term and prolonged priming of the two types of phagocytes (MP and PMNL) are discussed.

Animals↗