Biocompatibility of biphasic α,ß-tricalcium phosphate ceramics in vitro.

The biocompatibility of biphasic α,ß-tricalcium phosphate ceramics, obtained by annealing a compact preform based on ß-tricalcium phosphate powder, was studied in vitro. It was found that within 10-30 days the adhesion of primary dental pulp stem cells located on the surface of biphasic α,ß-tricalcium phosphate ceramics is suppressed. Decrease of the cell number on the surface of biphasic α,ß-tricalcium phosphate ceramics, most likely, can be associated with both the pH level (acidic) as a result of hydrolysis of the more soluble phase of α-tricalcium phosphate and with the nature of surface that changes as a result of the formation and growth of hydroxyapatite crystals.

Effect of sunlight transformed by luminophore-containing materials on cell functions in vitro and in vivo.

Effect of sunlight transformed by luminophore-containing materials on cell viability and functional state of the retina was assessed using the photodamage model. Exposure to the luminescent component of light improved viability of NIH 3T3 cells and promoted recovery of electric activity in rabbit retina after photodamage.

[The rate of detection and diagnostic significance of antibodies to Borrelia burgdorferri in patients with eyes diseases of inflammatory nature].

The eyes diseases appear at any stage of Lyme borreliosis and clinical manifestations are polymorphic and non-specific. The study examined prevalence of B. burgdorferi s.l. infection in patients with different eyes diseases and evaluated diagnostic significance of antibodies to B. burgdorferi in clinical practice. The sampling included 57 patients with conjunctivitis, keratitis, uveitis, choreoretinitis, optical neuritis of unclear etiology. The blood serum of patients was analyzed to detect presence of IgM- and IgG-antibodies to B. burgdorferi s.l. The positive results were confirmed in Western blot (two-sweep method). The immune enzyme analysis detected antibodies to B. burgdorferi in 7 out of 57 examined patients (12.3%). The Western blot confirmed presence of antibodies only in 3 serums out of 57 (5.3%). The high rate of false positive results was established during immune enzyme analysis detecting IgM-antibodies to B. burgdorferi. On the basis of comprehensive examination ophtalmo-borreliosis was diagnosed in two out of three patients seropositive to B. burgdorferi. In one seropositive patient co-infection B. burgdorferi provoked exacerbation of chronic uveitis of unclear etiology. It is appropriate to include in plan of examination of patients with inflammatory eyes diseases of unclear genesis the detection of antibodies to B. burgdorferi using two-sweep test (study of serums with immune enzyme analysis, confirmation of positive results in Western blot).

[Investigation of beta-endorphin nonopioid reception in preimplantation development of mouse embryo in vitro].

The effect of beta-endorphin on 2-, 4- and 8-cell embryo development in vitro was studied. It is shown, that hormone has no effect on 2-cell embryos development, but it has enhanced viability of 4- and 8-cell mouse embryos. The number ofblastocyst formation increases in presence of 0.1 microM beta-endorphin in embryo cultured medium but the number of blastocyst with abnormal structure decreases. The effect of hormone on the change of intracellular concentration of Ca2+ ion in 2-, 4- and 8-cell mouse embryo has been studied with the help of fluorescent microscopy. The effect of adenylate cyclase, and phospholipase activity blockers and opioid blocker naloxone on the change of intracellular concentration of Ca2+ ion in early mouse embryo in the presence of beta-endorphin have been also studied. It is shown that 2-cell embryo has opioid and nonopioid beta-endorphin receptors, whereas 4- and 8-cell mouse embryos have only nonopoioid beta-endorphin receptors. It is also shown that the effect of beta-endorphin in the early mouse embryo through a nonopioid receptors occurs with the participation of intracellular Ca2+ and adenylate cyclase signaling system.

Biosynthetic wound coatings as susbtrates for cell growth.

Experimental studies of composite materials formed on the basis of fluorine-containing latex and bioactive polysaccharides showed that physicochemical properties of composite materials and their adhesion characteristics can be modulated by variations of polysaccharide-latex ratio and the nature of polysaccharides. The ratio of components ensuring the formation of biosynthetic films that meet the standards for modern wound coating and maintain adhesion and growth of substrate-dependent mammalian cells was determined. These materials can considerably increase the efficiency of treatment of extensive and deep skin wounds in cases when application of cell cultures is indicated.

[Effect of the nitric oxide donors Na nitroprusside and L-arginine on the course of uveitis, the antioxidative and antiproteolytic potential of tear and blood in the experiment].

The nitric oxide (NO) donors Na nitroprusside and L-arginine were tested for their effects on the course of experimental immunogenic uveitis, antiproteolytic and antioxidative activities in the rabbit tear and blood. With the use of the NO donors, the course of uveitis was shown to be more severe and prolonged. In uveitis, there was a change in the activity of the antiproteinases--alpha1-antitrypsin and alpha2-macroglobulin and the antioxidative enzymes superoxide dismutase in both tear and blood. The magnitude of changes in the biochemical parameters under study suggested that the course of uveitis was more severe in the rabbits given the NO donors. Thus, the inclusion of the NO donors in the active phase enhances an inflammatory reaction in immunogenic uveitis.

Immobilization and long-term culturing of mouse embryonic stem cells in collagen-chitosan gel matrix.

We propose a method of creation of a 3D matrix consisting of native collagen fibers and natural polysaccharide chitosan. The collagen-chitosan hydrogels maintain viability and prolipherative activity of embryonic stem cells obtained from internal cells of mouse blastocyst. The proposed system forming hydrogels in situ can be used in cell therapy for immobilization and targeted delivery of stem cells.

Model of immunogenic uveitis in rabbits.

Six models of experimental immunogenic uveitis induced by injection of normal horse serum were tried in rabbits. A convenient working variant of the model was developed characterized by high activity and long duration of the inflammatory process in the eye. Creation of this model requires pre-sensitization (subcutaneous injection of 5 ml normal horse serum) followed by intravitreal injection of the resolving dose of horse serum on day 9. An adapted improved model of experimental immunogenic uveitis in rabbits is proposed.

Factors affecting survival of reconstructed mouse embryos after nuclear transfer.

Reconstruction of mouse embryos was performed by injection of donor genetic material from differentiated cells of various types (cumulus cells, cardiomyocytes, and epithelial cells) into recipient cells (mature oocytes and zygotes). A medium for microsurgery was selected, which enhanced survival of both embryonic and somatic cells during the reconstructive manipulations. Special preparation of somatic cells to transplantation was carried out, which employed factors synchronizing the cells in a certain phase of the cell cycle in order to enhance their capacity to maintain the development of reconstructed embryos. The processes of nucleus reprogramming in specialized cells under the action of cytoplasmic factors of oocytes and zygotes were examined. During in vitro culturing of reconstructed embryos, the most successful development was observed in embryos implanted with donor material from cumulus cells. Mouse embryos reconstructed with a certain genome and subsequent production and use of stem cells are considered as the model system for developing the basic principles of replacement therapy.

[A study of the effect of irradiation hardness on the properties of the fluoropolymeric matrix modified by polyanionic biologically active substances]. / Izuchenie vliianiia zhestkosti oblucheniia na svoistva ftropolimernoi matritsy, modifitsirovannoi polianionnymi biologicheski aktivnymi veshchestvami.

The properties of a synthetic substrate responsible for the behavior of substrate-dependent cells in the culture were studied. The effect of the composition of a system water-soluble biopolymer (sodium alginate or methyl cellulose)-synthetic latex SKF-26 and the effect of various types of radiations on its biophysical properties were studied. The results obtained indicate that the addition of water-soluble biopolymeric additives to synthetic polymeric films improves the adhesion of cells to the substrate, the adhesion being closely related to the concentration of additives. It was found that the modification methods that determine changes in the charge of the substrate affect the capacity of different cell types for adhesion and proliferation. It was also found that the hardness of irradiation does not affect the vapor permeability and the extent of film swelling.

[Hyperlipoproteinemias and proteinase inhibitor balance in patients with proliferative diabetic retinopathy with solid exudates in retina]. / Giperlipoproteidemii i proteinazno-ingibitornyi balans u bol'nykh proliferativnoi diabeticheskoi retinopatiei pri nalichii tverdykh ékssudatov v setchatke.

Studies of lipid metabolism and proteinase inhibitor balance in the blood of patients with proliferative diabetic retinopathy (PDR) revealed hyperlipoproteinemias (HLP) in 61%. Type IIa HLP predominated (32%), type IV HLP were diagnosed in 23%, and type IIb in 7% of cases. Solid exudations in the retina were 7 times more frequent in patients with type IV HLP and 5 times more frequent in those with type IIb HLP than in patients without HLP. The most expressed shifts of proteinase inhibitor balance towards increase of trypsin-like activity, which was not compensated for by the antitryptic potential, were observed in the same two groups. The data indicate that PDR patients with types IIb and IV HLP with increased blood proteolytic activity not compensated for by inhibitors are at a high risk of developing solid exudations in the retina. Therefore individual drug correction of lipid metabolism and proteinase inhibitor balance is recommended for maintaining visual function in diabetics. The treatment should be based on the results of clinical and biochemical studies.

[Parameters of blood proteinase inhibitor balance and hyperlipoproteinemia in patients with proliferative diabetic retinopathy with vitreous hemorrhage]. / Pokazateli proteinazno-ingibitornogo balansa krovi i giperlipoproteidemii u bol'nykh proliferativnoi diabeticheskoi retinopatiei s krovoizliianiem v steklovidnoe telo.

The parameters of proteinase-inhibitor balance and lipid metabolism were studied in the blood of patients with proliferative diabetic retinopathy. Metabolic disorders in patients with proliferative diabetic retinopathy with hemophthalmia are characterized by a notable increase in the activities of trypsin-like enzymes and alpha 2-macroglobulin level and normal activity of alpha 1-antitrypsin and shifted lipid metabolism parameters characteristic of types IIb and IV hyperlipoproteinemia. These data indicate a necessity of monitoring lipid metabolism and proteinase-inhibitor balance in patients with diabetic retinopathy in order to detect subjects at a high risk of hemophthalmia and timely start drug correction for preventing this complication.

[Results of the use of vasoactive preparation pikamilon in pigmented retinal abiotrophy]. / Rezul'taty primeneniia vazoaktivnogo preparata pikamilona pri pigmentnoi abiotrofii setchatki.

Eighty patients with pigmented retinal abiotrophy (PRA) and 20 controls were examined. The perfusion pressure and arteriovenous coefficient are markedly reduced in patients with stages 1-2 PRA, in comparison with controls. Deterioration of the visual function in patients with stages 3-4 PRA vs. that in stages 1-2 was associated with a more marked reduction of the hemodynamic parameters and the status of ocular vessels. Pikamilon therapy in a dose of 2 ml of 10% solution once a day intramuscularly for 10 days led to improvement of the visual function and ocular hemodynamics in patients with PRA. Treatment efficacy was higher in patients with disease stages 1-2. Pikamilon is recommended for the treatment of patients with PRA.

[Oxidation of p-nitrobenzylamine and p-dimethylaminomethylbenzylamine by amine oxidases from the human placenta and serum]. / Okislenie p-nitrobenzilamina i p-dimetilaminometilbenzilamina aminoksidazami platsenty i syvorotki krovi cheloveka.

Oxidation of p-nitro- and p-dimethylaminomethyl derivatives of benzylamine, catalyzed by amine oxidases from human placenta and blood serum, was studied. The amine oxidase activity was estimated by means of a spectrophotometric procedure involving measurement of aldehyde formed during the reaction after extraction with hexane. For extraction of benzaldehyde and p-nitrobenzaldehyde in the samples HCl was added up to the concentration of 0.17 M and for extraction of p-dimethylaminomethyl benzaldehyde--NaHCO3 up to the 0.5 M concentration. The reaction products were extracted with a yield of 94%, 83% and 78% respectively; molar extinction coefficients for aldehydes at the maximal absorption were equal to 13,080 (241 mn), 16,520 (258 nm), and 11,547 (248 nm), respectively. Analysis of the oxidative reactions using inhibitors Lilly 51,641, deprenyl, aminoguanidine and semicarbazide showed that monoamine oxidase of the A type (95%) and benzylamine oxidase (7%) catalyzed oxidation of 0.1 mM p-nitrobenzylamine in mitochondria and microsomes but oxidation of the substrate at 1 mM concentration was catalyzed by monoamine oxidase of the B type (20% in mitochondria and 35% in microsomes). In the soluble fraction oxidation of p-nitrobenzylamine was catalyzed mainly by diamine oxidase (55%); monoamine oxidase of the A type catalyzed oxidation of 30% of the amine, benzylamine oxidase-15%. The molecular activity of the mitochondrial monoamine oxidase of the A type with p-nitrobenzylamine as a substrate was equal to 61 nmol of the product per 1 mole of the enzyme per 1 min.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effect of new 2-propinylamine derivatives on mitochondrial monoamine oxidase activity]. / Vliianie novykh proizvodnykh 2-propinilamina na aktivnost' mitokhondrial'nykh monoaminoksidaz.

New derivatives of 2-propinyl amine were studied as possible inhibitors of mitochondrial monoamine oxidases (MAO) from rat liver and brain tissues. Kinetics of inhibition of the MAO activity (A and B types) is described for one of the substances studied -- N-(8-quinolyl methyl)-N-methyl-2-propinyl amine. Interaction of N-(8-quinolylmethyl)-N-methyl-2-propinyl amine with MAO of the A type (serotonin as a substrate) and of the B type (beta-phenylethylamine as a substrate) was studied by the kinetic method, which enabled to determine and quantitatively estimate the steps of enzyme-inhibitor complexes formation. The inhibition of the mitochondrial MAO A and B types by the substance was shown to include the steps of formation of dissociating enzyme-inhibitor intermediates with the subsequent irreversible modification of them. The data on K1 values, estimated in experiments with serotonin and beta-phenylethylamine as substrates, show that the affinity of N-(8-quinolyl methyl)-N-methyl-2-propinyl amine towards MAO of the A type was 10-fold higher than the affinity towards MAO of the B type. The rates of these complexes conversion into irreversibly blocked forms of the MAO A and B types was found to be similar.