[Pharmacological availability of erythromycin granules for children's use]. / Farmatsevticheskaia dostupnost' detskoi lekarstvennoi formy éritromitsina v vide granul.

Pharmaceutical availability of erythromycin granules with polymeric coating of different composition+ was studied. With an account of the ++anatomo-physiological features of a child organism and the properties of the antibiotic, acetylphthalyl cellulose in combination with hydroxypropyl methylcellulose or methyl cellulose was used as a film forming agent. The coated granules were estimated by such parameters as the time of disintegration and the rate of dissolution in various media. The results of the study showed that coating of the erythromycin granules with the film composed of acetylphthalyl cellulose and hydroxypropyl methylcellulose in the ratio of 8 to 2 provided the required protection of the antibiotic in acid media and high pharmaceutical availability of the drug.

[Production of liposomal preparations of streptomycin and dihydrostreptomycin]. / Poluchenie liposomal'nykh preparatov streptomitsina i digidrostreptomitsina.

The effect of the conditions of the formation of liposomal preparations of streptomycin and dihydrostreptomycin on incorporation of the antibiotics into the liposomes was studied. The liposomes were obtained with the detergent (cholate) method modified by the authors. The modification implies preliminary application of a 20 per cent antibiotic buffer solution on columns for gel filtration of a mixed mycellar antibiotic solution (20 per cent). The volume ratio of the preliminary applied buffer solution and the mixed mycellar solution is higher than 4:1. The new procedure is simple, readily reproduced, providing formation of the liposomal preparations characterized by high levels of the antibiotic incorporation (about 300 micrograms per 1 mg of lecithin). The preparations are stable with regard to the antibiotic release. The liposomes do not aggregate on storage for a long period (more than 6 months). The liposomal preparations thus formed may be useful as intravenous dosage forms of the antibiotics.

[Effectiveness of liposome-incorporated streptomycin in experimental tuberculosis in mice]. / Effektivnost' streptomitsina, vkliuchennogo v liposomy, pri éksperimental'nom tuberkuleze u myshei.

The chemotherapeutic efficacy of streptomycin incorporated into liposomes was studied on mice with experimental tuberculosis. Streptomycin incorporated into liposomes was prepared with the detergent method using purified egg lecithin, sodium cholate and streptomycin sulfate. The level of streptomycin incorporation into liposomes was 250-399 micrograms of streptomycin base per 1 mg lecithin. The size of the liposome was determined by electron microscopy. It was 40-80 nm. BALB/c and (CBA X C57B1(6)) F1 mice infected with M. tuberculosis H37Rv (0.1 mg of half-moist mass per mouse, intravenously) were used in the experiments. It was shown that the liposome-incorporated streptomycin injected intravenously on the 3rd or the 4th day (20 or 25 mg/kg) or 3 times on the 4th, 7th and 10th or the 12th days (50 or 67.5 mg/kg a day) after the infection inhibited the growth of M. tuberculosis in the spleen tissue, while analogous doses of streptomycin solution had no such an effect. With respect to the lung tissue, the antibacterial effect of the liposome-incorporated streptomycin was not potentiated. When the liposome-incorporated streptomycin was administered 3 times, the life-span of the animals was increased and the loss of the body weight was retarded as compared to the results of an analogous treatment course with the use of streptomycin solution. The acute toxicity of intravenous streptomycin incorporated into liposomes was lower as compared to that of streptomycin solution.