Effect of calcium phosphate materials on multipotent mesenchymal cells from exfoliated deciduous teeth (SHED cells) in vitro.

Various calcium phosphate ceramic materials were created and their effect on cultured mesenchymal cells from exfoliated deciduous tooth pulp was evaluated. Tricalcium phosphate ceramics provides best cell survival and is an optimal material for bone tissue engineering. Analysis of the effects of tricalcium phosphate ceramics on osteogenic differentiation of SHED cells suggests that this material potentiated dexamethasone-induced osteogenic differentiation, which manifested in the increased number of ossification foci and enhanced extracellular matrix production by cells. Thus, the tricalcium phosphate ceramics created by us is a promising biomedical material that can be used for tissue-engineered bone analogs.

[Disfunction of membrane-receptor system of blood cells in children with diabetes mellitus of type I and II].

When metabolic failure in children and adolescents with diabetes, are violations of the structural and functional properties of membrane - the receptor apparatus of cells, accompanied by a decrease in ATP levels, inhibition of activity of membrane-bound enzyme Na+, K(+)-ATPase, a sharp decrease in insulin binding receptor activity and decrease glucose uptake by cells that indicates a decline in cell sensitivity to insulin. Diabetes in children and adolescents occurs with lipid disorders, activation of the processes of lipid peroxidation, manifested increasing concentrations of both primary and secondary products of lipid peroxidation, changes in structural and functional properties of erythrocyte membranes, as well as disturbances in the antioxidant defense system. Changes in the studied indexes depend on the type of diabetes and duration of the disease. Imbalance in the system LPO-AOD in the background shows the development of dyslipidemia, oxidative stress, particularly pronounced in type 2 diabetes.

[Auxotrophy and utilization of oxidized and reduced mineral sulfur forms by Brevundimonas diminuta strains]. / Auksotrofiia i usvoenie oksilennykh i vosstanovlennykh mineral'nykh soedinenii sery shtammami Brevundimonas diminuta.

Connection between auxotrophy of Brevundimonas diminuta strains for sulphur-containing amino acids and presence of oxidized or reduced sulphur forms in the medium has been shown. When grown in synthetic medium supplied with sulphate or sulphite B. diminuta strains required cystine, biotin, pantothenate and vitamin B12 for growth and utilized very limited spectrum--from 8 to 12--carbon sources. In the presence of 5 g/l of thiosulphate in the medium instead of mentioned sulphur-containing salts strains of this species did not require cystine and assimilated the ammonium nitrogen. The intensity of their growth in these conditions was lower and carbon nutrition spectra more limited than in custine-containing medium. Tetrathionate, elemental sulphur, sulphide were less efficient than thiosulphate, but they also provided growth of B. diminuta strains in the media supplied with ammonium salts, necessary vitamins and such universal C-sources as aspartate, glutamate, proline. Neither oxidized nor reduced mineral sulphur forms were able to substitute sulphur-containing amino acids for Comamonas terrigena strain requiring methionine.

Fluviols, bicyclic nitrogen-rich antibiotics produced by Pseudomonas fluorescens.

Fifteen fluorescent pseudomonads, isolated from the rhizosphere of agricultural plants, were similar in both their phenotypic properties and the chemical nature of produced pigments, to the previously described Pseudomonas fluorescens var. pseudoiodinum. DNA-DNA hybridisation data showed their genetic similarity (but not identity) to different biovars of P. fluorescens. A family of antibiotics-fluviols belonging to pyrazolo-[4,3-e]as-triazine derivatives was isolated from studied strains; isolation, properties, antimicrobial and antitumour activity of fluviols are described.

[Method for measuring glutathione system parameters in human lymphocytes]. / Metodika opredeleniia pokazatelei sistemy glutationa v limfotsitakh cheloveka.

The levels of reduced glutathion, activity of glutathion peroxidase, and glutathion S-transferase were measured in human peripheral blood mononuclears. The adapted methods permit measurements of glutathion system parameters in immunocompetent cells and can be used in patients with different immunopathological processes.

[Clinical fluorescent diagnosis of tumors using photosensitizer photogem]. / Klinicheskaia fliuorestsentnaia diagnostika opukholei s fotosensibilizatorom fotogemom.

During clinical trials of photodynamic therapy (PDT) the tissue fluorescence spectra under 510 nm laser excitation were recorded in 22 patients with tumors of the lungs, larynx, skin, gastric and esophageal carcinoma, and cancer of the gynecological organs before (autofluorescence) and after drug administration. A spectroscopic fluorescence detection system, developed at the General Physics Institute, Russian Academy of Sciences, was applied for tumor diagnostics. The system has been used for clinical fluorescence diagnostics with the aid of HPD-type photosensitizer Photogem (Moscow Institute of High Chemical Technologies) marked by selective retention in malignant tumors. Methods and equipment for spectra analysis aimed at estimating drug distribution in the near-surface layers of tissues, determining the tumor boundaries before photodynamic treatment, as well as studying drug pharmaco kinetics have been developed and tested. The results demonstrate the possibility of tumor detection by fluorescence even in low selectivity of drug accumulation which appears to be dependent on the stage and type of the disease and the organ involved.

[Photodynamic therapy and fluorescent diagnosis of malignant tumors using preparation photogem]. / Fotodinamicheskaia terapiia i fliuorestsentnaia diagnostika zlokachestvennykh opukholei preparatom fotogem.

From February, 1992 to May, 1993 photodynamic therapy (PDT) was applied at the State Scientific Center of Laser Medicine and the Moscow Scientific-Research Oncological Institute for the treatment of 60 patients with primary and metastatic malignant tumors of the breast, skin, respiratory and digestive organs, female reproductive organs, and urinary bladder. Forty-eight patients underwent one course of PDT, 11 patients received 2 courses, and one patient was given 3 courses. Russian-produced Photogem was used as the photosensitizer. It was infused intravenously 24, 48, or 72 hours before exposure to laser beam. The dose of Photogem ranged from 2.5 to 6.0 mg/kg. The density of laser radiation power during PDT sessions ranged from 100 to 1,600 mVt/cm2, energy exposure from 80 to 600 J/cm2, duration of irradiation from 3 to 45 minutes. After treatment the patients were studied in follow-up periods of 4 weeks to 17 months. Complete regression of the tumor verified morphologically was found in 62%, partial regression in 34%, and limited response or absence of an effect in 4% of cases. Fluorescent-diagnostic examination of patients was conducted at the Moscow Scientific-Research Oncological Institute. It demonstrated the reliability of this diagnostic method with the use of the preparation Photogem as the photosensitizer.

[Mechanism of action of the antineoplastic antibiotic asterin on cellular factors of immunogenesis regulation]. / Mekhanizmy vliianiia protivoopukholevogo antibiotika asterina na kletochnye faktory reguliatsii immunogeneza.

Asterin is a novel antitumor antibiotic isolated from a medicinal plant of the aster family in the Department of Antibiotics of the Institute of Microbiology and Virology of the National Academy of Sciences of the Ukraine. The mechanisms of its influence on the host antitumor resistance were studied. Asterin was shown to promote the modulation of the specific and nonspecific link of the antitumor resistance. It activated to a definite extent the effector productive phase with the dominating influence on the proliferative phase. The antibiotic immunocorrective action was achieved via the recovery of the suppression mechanism controlling the proliferation and differentiation of all the cell populations. The molecular mechanisms of the asterin action on the lymphocyte transformation characterized by an increase in the metabolism and synthesis of the membrane phospholipids are likely associated with the control of their free radical processes.

[The subcellular distribution of the glutathione system enzymes in the brain tissue of the rat]. / Subkletochnyoe raspredelenie fermentov sistemy glutationa v tkani golovnogo mozga krysy.

Using the percoll density gradient method for rapid isolation of organelles the distribution of glutathione system enzymes in the rat brain was characterized including glutathione S-transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR). In the fraction of mitochondria, the shares of GPx, GR, and GST were found to be as much as 92, 61, and 15% from their respective general activities. No enzymatic activity was found in lysosomes. Fractions of organelles with low density (microsomes, Golgi complex, cytoplasmic membranes) were cross-contaminated. Nevertheless, on the base of the established dynamics of distribution of the marker enzyme activity among various cell organelles it is suggested that, besides mitochondria, the glutathione system enzymes may be localized primarily in the endoplasmic reticulum, rather than in other organelles.

[Amyloidosis in systemic lupus erythematosus]. / Amiloidoz pri sistemnoi krasnoi volchanke.

Based on the authors' experience from 1982 to 1990 it was noted that out of 26 cases of renal amyloidosis in the presence of nonpurulent and purulent conditions 2 patients (7%) demonstrated the association with systemic lupus erythematosus (SLE). It was also noted that amyloidosis developed in the patients with a long history of the disease. Long-course immunosuppression treatment could be regarded as the other factor-of-risk for amyloidosis development. Histochemical examination of both patients demonstrated that amyloid deposits in the renal glomeruli were resistant to the potassium permanganate effect and consisted of AL-protein. The results obtained indicated the possibility of appearance of immunoglobulins AL--the proteins of the primary amyloidosis--synthesized in the spectrum in the SLE presence as well as their deposition in the renal glomeruli. As a possible cause of proteinuria and the nephrotic syndrome in SLE patients amyloidosis should be diagnosed in the life time and be regarded in the choice of therapeutic policy as well as in the assessment of pulse immunosuppressive therapy practicability.

[Regulation of immuno- and hematopoiesis with asterin]. / Reguliatsiia immuno- i gemopoéza asterinom.

It was shown that asterin, a higher plant preparation, had a marked antiblastomic action and a favourable effect on differentiation of the precursor cells and blood cells. It accelerated proliferation, migration of the truncal hemopoietic cells and their transfer from the dormant state into the cellular cycle. It also changed the cell differentiation in the direction of myelopoiesis. The mechanism of the asterin's immunomodulating action was found to be associated with regulation of T-cellular immunity and T-dependent immune response.

[Immunomodulating mechanism of the antitumor effect of asterin]. / Immunomoduliruiushchii mekhanizm protivoopukholevogo deistviia asterina.

It was shown that asterin therapy performed on a model of spontaneous metastasis markedly changed the content of the thymus serum factor in mice and normalized its level. The inducing mechanism of the drug's antitumor action was realized both at the stage of the metastatic postinvasion phase and during its terminal period which was probably due to an increase in the influence of the thymus on the immune system and evident from an increase in the therapeutic action of the drug.

[Antioxidant effect of the antineoplastic antibiotic obtained from a plant of the family Asteraceae]. / Antioksidantnoe deistvie protivoopukholevogo antibiotika, poluchennogo iz rasteniia semeistva slozhnotsvetnykh.

Antitumour antibiotic from a plant of the family Asteracea has been studied for the biochemical mechanism of its action. Redox processes were tested by the method of spontaneous chemiluminescence determining the intensity of freely radical oxidation of membrane cell phospholipids. It was established that the antibiotic under study stabilized the indices of spontaneous chemiluminescence up to the normal level.

The effect of Staphylococcus aureus enterotoxin A on proliferation of lymphoid and nerve cells.

The effects of Staphylococcus aureus enterotoxin A (SEA) on proliferative activities of human peripheral blood lymphocytes, B-lymphoma cells of the Namalva line, and nerve cells of the PC12 line have been studied. It has been shown that SEA affects these cells in identical ways, producing either a mitogenic or an antiproliferative effect. Studies on the dynamics of cellular responses to the action of SEA have demonstrated that the effects of the toxin are mediated by its interaction with different binding sites on the membranes of target cells. It has been established also that the antiproliferative effect of SEA is not associated with changes in 2',5'-oligo(A)-synthetase activity or in the level of interferon secretion.

Aerobic spore-forming bacteria as aetiological factors of bacteriaemia.

The paper presents data from the literature and results of the authors' own studies on the aetiological role of aerobic spore-forming bacteria in the development of bacteriaemia in man. Special attention is paid to various diseases caused by micro-organisms of the genus Bacillus. The importance of species-specific identification of bacilli isolated from blood and comprehensive study of pathogenicity of these bacteria is discussed.

[Antibodies to viruses in children with diabetes mellitus]. / Antitela k nekotorym virusam u detei v dinamike sakharnogo diabeta.

Serological studies were carried out in the time course of insulin-dependent diabetes mellitus in 419 children, among whom paired sera from 66 were studied in the very beginning of diabetes mellitus. By seroconversion in 83% of the children early in the disease, different, frequently mixed virus infections were diagnosed: Coxsackie B2, B3, B4 (46%), rubella (41%), influenza A, B, C (38%), parainfluenza types 1-3 (35%), mumps (23%), adenovirus infection (18%), HB virus infection (4.5%). Acute respiratory diseases preceded or coincided with the onset of diabetes in half of the children with diagnosed acute respiratory and enterovirus infections. No clinical signs of rubella, mumps, or hepatitis immediately before the onset of diabetes or early in the disease were found. A possible role of virus infection diagnosed early in diabetes, in the etiology of chronic insulitis, in provocation of its exacerbation, and manifestation of diabetes mellitus is discussed.