[Some factors influencing the efficiency of disk-diffusion test to determine the antibiotic sensitivity of microorganisms].

On diffusion of an antibiotic from the disk to the nutrient medium, gel concentration of an antibiotic changes. This process is individual for each antibiotic. The action of different concentrations of the antibiotic at different intervals results in the suppression of microbial growth around the disk (formation of a zone). The relationship between the antibiotic concentration in the disk and the diameter of a microbial growth suppression area is proportional in the limited range of concentrations. The relationship between the concentration of an antibiotic and the diameter of a growth suppression area may greatly vary for various taxonomic groups of microorganisms and for various strains. The established fact may be responsible for the disagreement of results of a microbial antibiotic sensitivity test, by using different methods and makes the standardization of the disk-diffusion test difficult.

[Radiologic diagnosis of Payr disease in children]. / Rentgenodiagnostika bolezni Paira u detei.

The experience with diagnosis of Payr disease in 119 children with the use of a roentgenologic method, in particular, irrigoscopy was summarized. Falling of the right colic flexure with formation of abrupt kinks of the transverse colon, and retention of contrast substance in the right portion of the large intestine are the main roentgenologic signs of the Payr disease.

[Characteristics of antibiotic use in children]. / Usobennosti primeneniia antibiotikov u detei.

In antibiotic therapy of children bacteriological findings should be considered. The choice of antibiotic doses depends on the drug pharmacokinetics and damaging effect, the state of the excretory organs and some other factors. Antibiotic elimination in children during the postnatal period is limited: there is a relationship between the gestation term and intensity of drug elimination. Antibiotics penetrate through the placental barrier. They are detected in the mother milk. The damaging effect of antibiotics in many respects depends on their properties, dosage and administration route. Children are more sensitive to the direct toxic action of antibiotics as compared to adults. Development of dysbacteriosis in children is frequent. Allergic reactions with diverse clinical signs are possible in children. Combined antibiotic therapy with observation of definite requirements is more efficient. Still, because of the antibiotic damaging effect monotherapy is more preferable in all possible cases.

[Effect of various microorganisms on the activity of levorin]. / Vliianie nekotorykh mikroorganizmov na aktivnos't levorina.

Levorin added to nutrient media with growing cultures of aerobic gram-positive bacilli, Escherichia, enterococci and filamentous fungi was partially inactivated. The antibiotic activity decrease depended on the strain characteristics, incubation period and temperature. Fermentation broth filtrates of the experimental strains also inactivated levorin while to a lesser extent than the growing organisms. In contaminated levorin pastes, the antibiotic activity was lower. The fermentative nature of inactivation was not proved.

[Chemotherapy of bacteroides infection under clinical and experimental conditions]. / Khimioterapiia bakteroidnykh infektsii v klinike i eksperimente.

Bacteroides were detected in pus and bioptates of the majority of 125 patients with purulent and purulent septic infections of various localization. In 90 per cent of the subjects the bacteroides were detected in association with aerobes, facultative and obligate anaerobic bacteria. The species of the bacteroides and concomitant microflora isolated from the cases with different diseases were defined by endogenic sources of the microbial contamination. Sensitivity of 112 bacteroide strains to antimicrobial agents was tested. Chloramphenicol, clindamycin, metronidazole, cefotaxime and heliomycin proved to be the most efficient. Efficacy of heliomycin was detected in hamsters with experimental bacteroide infection in the buccal sac. Thorough bacteriological examination is required for rational chemotherapy of bacteroide infections.

[Rapid determination of microbial sensitivity to antibiotics by using laser spectroscopy]. / Uskorennoe opredelenie chuvstvite'lnosti mikroorganizmov k antibiotikam s ispo'lzovaniem lazernoi spektroskopii.

A method of express-determination of the susceptibility of microbes to antibiotics is presented based upon the registration by the method of laser spectroscopy of changes of optic properties of cultures at early terms of their incubation in liquid nutrient media with addition of antibiotics. The method was elaborated in 13 standard strains of Staphylococcus aureus and Escherichia coli with antibiotics of different classes, tested on the microflora of pus of patients with sepsis, verified by the method of serial dilutions of the antibiotic. The method makes it possible to obtain the minimum inhibiting concentration of antimicrobial preparations 1 h after the moment of obtaining the native material.

[Use of different nutrient medium variants in determining the antimicrobial activity of neomycin]. / Ispol'zovanie razlichnykh variantov pitatel'nykh sred pri opredelenii antimikrobnoi aktivnosti neomitsina.

Gel diffusion regularities with respect to neomycin sulfate substances differing in their composition and the antibiotic separate components were studied on nutrient media of diverse composition. Optimal conditions for standardization of neomycin sulfate antimicrobial activity with using the agar diffusion method and synthetic medium are determined.

[Microcomputer-based automation of the microbiological analysis of antibiotic activity]. / Avtomatizatsiia mikrobiologicheskogo analiza aktivnosti antibiotikov na baze mikroEVM.

Laboratory informative computer systems (LICS-10 and LICS-11) for microbiological assay of antibiotics were developed. The systems are based on the ISKRA-1256 computer. As compared to the routine method with the use of the well-known V. S. Dmitrieva's Tables the LICSs provide more than a 2-fold decrease in the working hours of the assay. The data on the specific software for the LICSs are presented and the algorithms for the calculations are described.

[Organizational and methodologic aspects of antibiotic therapy in a surgical clinic]. / Organizatsionno-metodicheskie aspekty antibiotikoterapii v khirurgicheskoi klinike.

The article presents modern ideas of the most rational methods of antibiotic therapy in treatment of patients in the surgical clinic.

[Effect of kerogen oxidation products on the biosynthesis of beta-lactamases by Escherichia coli]. / Vliianie produktov okisleniia kerogena na biosintez beta-laktamaz esherikhiiami.

Shale acid concentrate (SAC) and ozonid, the products of water-alkaline oxidation of kerogen stimulated production of beta-lactamases by E. coli. The effect was most pronounced when the SAC was added to the fermentation nutrient medium. Kerogen ozonid was inferior by its activity. Cultivation of the seed material on media containing both the products of kerogen did not influence the enzyme production. Stimulating effect on production of either penicillinases or cephalosporinases was observed. SAC and ozonid had no influence on the culture growth, multiplication and biomass accumulation.

[Standardized nutrient medium for determining the biological activity of antibiotics of the aminoglycoside group]. / Unifitsirovannaia pitatel'naia sreda dlia opredeleniia biologicheskoi aktivnosti nekotorykh antibiotikov aminoglikozidnoi gruppy.

The possibility of the use of nutrient media containing only salt components in addition to agar-agar in determination of the biological activity of aminoglycoside antibiotics was confirmed. The optimal results were obtained on the medium including ammonium acetate, disubstituted sodium phosphate and agar-agar. Glucose was added to the medium simultaneously with the test microbe. The medium is simple by its composition. It provides satisfactory growth of B. subtilis ATCC 6633 as the test microbe and clear inhibition growth zones of sufficient size. The results of the assay of the biological activity of neomycin, monomycin, streptomycin and kanamycin on the medium of this composition were reproducible.