[The protective properties of the lysosomal form of Pseudomonas aeruginosa anatoxin in a test of its active protection of experimental animals]. / Izuchenie protektivnykh svoistv liposomal'noi formy anatoksina Pseudomonas aeruginosa v teste aktivnoi zashchity éksperimental'nykh zhivotnykh.

The protective activity of the liposomal form of P. aeruginosa toxoid and intact phosphatidylethanolamine liposomes has been evaluated in mice with experimental P. aeruginosa infection. It has been revealed that the liposomal form of P. aeruginosa toxoid, introduced in a single injection, ensures the formation of more intense and prolonged immunity in comparison with that induced by the toxoid adsorbed on aluminum hydroxide. This investigation has revealed that intact phosphatidylethanolamine liposomes also possess protective properties, protecting 10-36.7% of the animals from infection with P. aeruginosa toxigenic strain.

[Experimental and clinical study of nitazol as an antibacterial drug in the complex treatment of peritonitis]. / Eksperimental'no-klinicheskoe izuchenie nitazola kak antibakterial'nogopreparata v kompleksnom lechenii peritonitov.

Antibacterial properties of the Soviet drug nitazol which is a derivative of imidazole were studied. It was shown that nitazol in a dose of 4-8 micrograms/ml was highly active against gram-negative nonsporulating anaerobes, gram-positive anaerobic cocci and spore-forming Clostridia spp. Unlike metronidazole, it was efficient against both standard and clinical strains of facultative anaerobes such as E. coli, S. aureus and Klebsiella spp. isolated from patients with peritonitis and being poly-resistant to antibiotics. It was found in vitro that the antibacterial effect of nitazol was higher when it was used in combination with some antibiotics. It was demonstrated on experimental models of peritonitis caused by Staphylococcus spp. and E. coli in mice that nitazol used alone or in combination with gentamicin had a favourable effect on the animal survival and lifespan. The combination of nitazol with gentamicin was applied in the combined treatment of appendicular peritonitis in 80 children and its high therapeutic efficacy was stated. Nitazol is useful as an antibacterial drug in the combined treatment of children with purulent peritonitis.

[Evaluation of liposomal forms of rifampicin and prodigiozan in the treatment of experimental chronic tonsillitis]. / Otsenka liposomal'nykh form rifampitsina i prodigiozana pri lechenii éksperimental'nogo khronicheskogo tonzillita.

Therapeutic effect of liposomal dosages of rifampicin and prodigiozan was studied on rabbits with simulated chronic tonsillitis in comparison to that of commercial ones of the drugs. The treatment schemes included daily intra-tonsillar++ injections of the dosage forms for 5 days. A high efficacy of their liposomal dosage forms in treatment of experimental chronic tonsillitis was confirmed microbiologically and immunologically. Approval of the liposomal dosage forms used in the therapy of patients with chronic tonsillitis requires clinical trials.

[Antibacterial activity of nitazole and its use in combined treatment of appendicular peritonitis in children]. / Antibakterial'naia aktivnost' nitazola i primenenie ego v kompleksnom lechenii appendikuliarnogo peritonita u detei.

The experimental-clinical investigations have demonstrated the high effectiveness of the native preparation Nitazole against the Gram-negative non-spore-forming anaerobic bacteria, Gram-positive anaerobic cocci, spore-forming Clostridium, certain facultative anaerobes. This permits to recommend it for the use as an antibacterial preparation for the treatment of peritonitis in children.

[Immunogenic properties of the liposomal form of Pseudomonas aeruginosa anatoxin]. / Immunogennye svoistva liposomal'noi formy anatoksina sinegnoinoi palochki.

Studies of immunogenic properties of P. aeruginosa anatoxin incorporated into liposomes of varying lipid compositions have shown that single immunization of mice with the anatoxin included into phosphatidyl ethanolamine and lecithin cholesterol liposomes induces a 6-8-fold higher antitoxin antibodies production than immunization with unadsorbed or adsorbed on aluminum hydroxide P. aeruginosa toxoid. The maximal production of antibodies against exotoxin A of P. aeruginosa is observed already on the 14th day. The adjuvant properties of lecithin-cholesterol liposomes were revealed only in the primary immune response, while phosphatidyl ethanolamine-containing liposomes exhibited the capacity for enhancing both the primary and the secondary immune responses. The use of liposomal P. aeruginosa anatoxin made of lipids varying in composition and charge is a promising trend of research aimed at designing new highly effective immunization preparations for P. aeruginosa infection prevention.

[Structural transformations and aggregation stability of lecithin liposomes in cryoprotective media]. / Strukturnye prevrashcheniia i agregatsionnaia ustoichivost' letsitinovykh liposom v sredakh s krioprotektorami.

To study the structural transformations and aggregation stability in liposomes, a new approach is proposed whose efficiency is demonstrated during the analysis of light scattering by lecithin liposome sols doped with low-molecular cryoprotectors . This approach is used to determine absolute dimensions, relative values of weight concentration, masses of vesicules and their surface densities as well as their polydispersity characteristics. The anisotropic scattering data suggest that cryoprotectors eliminate small scale defects which are partially restored at low temperatures. Low-molecular cryoprotectors are found to produce some favourable changes in dimensions and distribution of liposomes and to increase their aggregation and structural stability.

[Isolation and low-temperature preservation of liposomes containing rifampicin]. / Poluchenie i nizkotemperaturnoe konservirovanie liposom, soderzhashchikh rifampitsin.

The optimal conditions for preparations of rifampicin-containing liposomes were determined with the methods of mechanical shaking, gas dispersion and and reversible phases. It was found that the percentage of rifampicin incorporation into liposomes depended on the molar ratio of the antibiotic to the lipid (the optimal ratio was 1 : 10), the size and structure of liposomes, the amount of cholesterol added and the lipid membrane charge. Incorporation of rifampicin amounted to 16.1 +/- 2.4, 39.2 +/- 3.2 and 60.5 +/- 2.9 per cent with respect to neutral lecithin multilamellar liposes, liposomes prepared with the gas dispersion method and liposomes prepared with the method of reversible phases, respectively. Cholesterol in a molar ratio to lecithin equal to 2 : 5 or higher and dicetyl phosphate imparting the negative charge to the membrane had an inhibitory effect on the drug uptake by liposomes, while stearyl amine having the positive charge had a stimulating effect. The effect of the cryoprotectors glucose, polyvinylpyrrolidone, poly-ethylene glycole-400 and glycerol on low-temperature preservation and storage of rifampicin-containing liposomes was studied. It was shown that 10--15 per cent solutions of sucrose and glucose had the highest cryoprotective effect, when the two-stage method of freezing was used. It provided almost 84 per cent preservation of liposomal rifampicin. Electron microscopy showed that after defrosting liposomes no significant changes in the size and structure of lipid membranes were observed.

[Structural and aggregational stability of lecithin liposomes based on light-scattering data]. / Strukturnaia i agregatsionnaia ustoichivost' letsitinovykh liposom po dannym svetorasseianiia.

The light scattering method for investigation of structural and aggregate stability is proposed, based on the comparison between angle and time dependence of total intensity of scattering light and its depolarized component. The structural evolution of liposome is observed by the anisotropic light scattering method. It is shown that the sols aggregate stability violation follows the appearance and increase of small-scale defects of vesicules. The interpretation of light scattering data is confirmed by electron micrographs.

[Effect of thymosterin A on the immunological reaction of mice]. / Vplyv tymosterynu A na imunolochichnu reaktisiiu myshei

Proliferaiton of thymus-dependent lymphocytes and immunological reaction of the line CBA mice immunized with sheep erythrocytes was studied as affected by thymosterol A. The data obtained confirmed the authors' assumptions on a stimulation effect of thymosterol A on division of thymocytes. Introduction of the mentioned preparation against a background of the antigenic aciton of sheep erythrocytes causes an increase in the amount of cells synthesizing hemolysins more than by 60% as compared to the control. The preparation effect depends on the dose. The data are presented, which makes it possible to assume that the mentioned effects may be due to the action of thymosterol A on the content and activity of the intracellular cyclic AMP.