Biological properties of sherry yeasts in the presence of antimicrobial preparations

The wine yeasts Cheres were not sensitive to high concentration (500 gamma/ml) of benzylpenicillin, streptomycin, tetracycline, oxytetracycline, chlortetracycline, morphocycline, erythromycin, oleandomycin, monomycin, neomycin, kanamycin, polymyxin, ampicillin, oxacillin, methicillin, ceporin, ristomycin, levomycetin, furadonin and furazolidone. In concentrations of 50 to 500 gamma-ml oleadomycin, chlortetracycline, oxytetracycline, kanamycin and ristomycin inhibited synthesis of the Cheres yeast biomass. Benzylpenicillin, polymyxin, neomycin and ampicillin in concentrations of 50 to 100 gamma/ml had a stimulating effect on the yeast biomass synthesis.     

Antibiotic sensitivity of the causative agents of suppurative surgical infection]

Sensitivity of 1492 strains of the causative agents of the surgical purulent infections, i. e. pathogenic Staphylococcus, Proteus, Ps. aeruginosa and E. coli to benzylpenicillin, streptomycin, levomycetin, tetracycline, erythromycin, oleandomycin, monomycin, kanamycin, novobiocin, ampicillin, oxacillin, ceporin, gentamicin and rifampicin was studied. Gentamicin was most active against all the bacterial species tested. The staphylococci were in addition sensitive in a high percentage of the cases to rifampicin, novobiocin, ceporin, monomycin and kanamycin. The isolates of E. coli were in addition sensitive to ceporin, monomycin and kanamycin. Sensitivity of the strains of Ps. aeruginosa and Proteus was low to all of the antibiotics except gentamycin. Most of the strains of the causative agents of the surgical purulent infections were multiresistant to 4 antibiotics. The number of the staphylococcal strains sensitive to benzylpenicillin, streptomycin and levomycetin increased in 1976 as compared to 1975 on the background of a limited use of these antibiotics in clinics.     

Antibiotic resistance of Pseudomonas aeruginosa strains isolated from patients with infected burns

Sensitivity to 15 drugs of 248 P. aeruginosa strains isolated from patients with infected burns was studied by the method of agar dilution. All of the strains were resistant to polymyxin M, ceporin, erythromycin and oleandomycin. Most of the strains were resistant to streptomycin, monomycin, ampicillin and rifadin. Moderate resistance of the strains to carbenicillin, morphocycline, vibramycin, kanamycin, tetraolean and tetracycline was observed: the maximum concentrations of these antibiotics (128 microgram/ml) inhibited the growth of 85, 69, 63, 51.8, 43.6 and 41.2 per cent of the strains respectively. Gentamicin proved to be most active against the strains of P. aeruginosa and inhibited 87 per cent of the strains when used in the therapeutic doses. The study provided recomendation of the drugs for parenteral and local use in treatment of burns infected with P. aeruginosa.     

Sensitivity of pathogenic clostridia to antibiotics]

By the sensitivity levels of the gas infection causative agents, i. e. pathogenic Clostridia to antibiotics, the latter were conditionally divided into 4 groups. The 1st group included the most active antibiotics, such as tetracyclines,, penicillins, cephalosporins, rifampicin, 7-chlor-7-desoxylincomycin. Their minimum inhibitory and bactericidal concentrations did not usually exceed 2 gamma/ml. For most of the strains the inhibitory and bactericidal concentrations amounted to the tenth and hundredth fractions of gamma/ml. The antibiotics of the 2nd group, i. e. erythromycin, lincomycin,ristomycin and levomycetin inhibited multiplication and viability of pathogenic Clostridia in concentrations of 20 gamma/ml. Erythromycin was most active among them The 3rd group consisted of oleandomycin, novobiocin, geliomycin and azalomycin, the minimum inhibitory concentrations of them being 20 to 50 gamma/ml. The antibiotics of the 4th group, i. e. neomycin, monomycin, kanamycin, streptomycin, polymyxin and others affected pathogenic Clostridia at very high concentrations, amounting to the hundrenth and thousandth of gamma/ml.     

Antibiotic sensitivity of Proteus, Pseudomonas pyocyanea and staphyloccoci isolated from scleroma and ozena patients]

Antibiotic sensitivity of 292 strains of Proteus, 60 strains of Ps, aeruginosa, 309 strains of S. aureus and 88 strains of S. epidermidis isolated from the upper respiratory tract of patients with scleroma and ozena was studied. The cultures of Pr. mirabilis were sensitive to aminoglucosides (54.9-96.2 per cent) and Pr. morganii were sensitive to levomycetin (81.5 per cent) and neomycin (92.6 per cnet). Sensitivity of Pr. vulgaris and Pr. morganii was reliably higher (p less than 0.001) than that of Pr. mirabilis. The strains of Pr. morganii were less sensitive to monomycin (P less than 0.001) and streptomycin (p less than 0.01) as compared to the cultures of other Proteus species tested. The strains of Ps. aeruginosa were sensitive only to gentamicin (90 per cent) and neomycin (81.1 per cent). Most of the strains of S. aureus (85.4-100 per cent) were sensitive to oleadomycin, erythromycin, olemorphocycline, tetraolean, oxacillin, methicillin ceporin, lincomycin, ristomycin, kanamycin, monomycin and gentamicin. Benzylpenicillin (90.8 per cent of the sensitive strains), ampicillin (67.1 per cent), tetracycline (66.7 per cent), levomycetin (68.6 per cent) and streptomycin (38.1 per cent) were less effective. Antibacterial therapy in cases with scleroma and ozena should be directed not only against causative agents of the diseases but also against the microbes developing due to disbacteriosis. Combination of parenteral and local use of the antibiotics in the treatment of chronic clebsiellesis decreased the isolation rate of Proteus and Ps. aeruginosa in the patients.     

Structure of the antibiotic resistance of the salmonellae found in Transcarpathia]

Resistance of 1280 strains of Salmonella of various serological types isolated in the Zakarpatskaya region within 1967-1976 was studied with respect to benzylpenicillin, streptomycin tetracycline, levomycetin, monomycin, neomycin, erythromycin and oleandomycin. An Increase in the resistance of Salmonella to streptomycin, tetracycline, levomycetin, monomycin and neomycin was shown. During the last years Salmonellae carrying 4-8 resistance determinants were spreading in the region. Among S. typhimurium strains with 7-8 resistance determinants predominated (58.8 per cent). The cases of salmonollosis were mainly due to these strains.     

Sensitivity of Shigella to antibiotics]

Three hundred and twenty two Shigella cultures isolated from dysentery patients within 1986-1989 were tested with the use of standard paper disks for their sensitivity to levomycetin, streptomycin, tetracycline, monomycin, neomycin, kanamycin, erythromycin, gentamicin, carbenicillin, ampicillin, oxacillin, methicillin and doxycycline. The number of the cultures belonging to Shigella sonnei amounted to 85.1 per cent of the total number of the strains studied. 91.9, 89.5, 87.3, 87.3, 80.1 and 80.1 per cent of the cultures were sensitive to gentamicin, kanamycin, carbenicillin, neomycin, levomycetin and ampicillin, respectively. 99.4 per cent of the isolates were resistant to streptomycin and 97.2 per cent were resistant to tetracycline. The sensitivity to erythromycin remained rather high (70.2 per cent). The overwhelming majority of the Shigella sonnei isolates had multiple resistance.     

Antibiotic sensitivity of the bacterial microflora from the sputum of children with acute pneumonia]

Bacteriological analysis of sputum of 598 children with acute pneumonia was performed. Sensivity of 1348 cultures belonging to 8 bacterial species with respect to benzylpenicillin, streptomycin, chloramphenicol, tetracycline, oxytetracycline, chlortetracycline, erythromycin, oleandomycin, neomycin and monomycin was determined. It was shown that the sputum microflora was often resistant to the antibiotics widely used in the medical practice for prolonged periods of time, such as benzylpenicillin, streptomycin, chloramphenicol, tetracyclines. However, it usually remained sunsitive to neomycin, monomycin, erythromycin and oleandomycin. It was found that antibioticogrammes defining the antibiotic choice were of great significance for therapy of acute pneumonia.     

Sensitivity to antibacterial preparations of the pseudotuberculosis bacteria isolated on the territory of the Ukraine]

Sensitivity of 92 strains of the causative agent of pseudotuberculosis isolated in the Ukraine was studied with respect to 26 antibacterial drugs. It was found that the strains of the pseudotuberculous bacteria were sensitive to 17 drugs, i.e. benzylpenicillin, ampicillin, carbenicillin, cephaloridin, chloramphenicol, tetracycline, streptomycin, neomycin, monomycin, kanamycin, gentamicin, polymyxin, colistin, furadontin, nalidixic acid, sulfisoxazol and septrin. No differences in the sensitivity of the strains isolated in various districts of the Ukraine and from various sources were found. By their antibiotic sensitivity the strains isolated in the Ukraine did not differ from the cultures isolated in other districts of the USSR and abroad.     

Comparative analysis of antibiotic sensitivity of Streptococcus pneumoniae strains isolated from patients and carriers

The data on antibiotic sensitivity of 38 strains of S. pneumoniae isolated from children and 46 strains isolated from carriers are presented. The isolates from the carriers had significantly higher sensitivity to benzylpenicillin, ampicillin, methicillin, oxacillin, cefazolin, erythromycin, oleandomycin and lincomycin. Resistance to gentamicin was more frequent in the strains isolated from the carriers. Among the strains of S. pneumoniae isolated from the patients and carriers representatives of serovar K19 were more frequent. There were no statistically reliable difference in them by sensitivity to benzylpenicillin, ampicillin, cefazolin, lincomycin and rifampicin. Still, the isolates from the carriers were much more sensitive to methicillin, oxacillin, oleandomycin and erythromycin.     

Comparison of the sensitivity of Pseudomonas aeruginosa cultures that synthesize melanin and other pigments to 12 antibiotics and 5-nitro-8-quinolinol]

Sensitivity of 80 Pseudomonas aeruginosa cultures forming melanin and 80 cultures synthesizing other pigments to amikacin, gentamicin, kanamycin, carbenicillin, levomycetin, monomycin, 5-NOK, polymyxin M, rifampicin, streptomycin, tetracycline, tobramycin and erythromycin was determined. It was found that the cultures of Ps. aeruginosa synthesizing melanin were less resistant to most of the antibiotics that the other representatives of this species.     

Production of hydrolases by lactic acid bacteria and bifidobacteria and their antibiotic resistance

It was demonstrated that bifidobacteria and lactic acid bacteria B. adolescentis and Lactobacillus sp. synthesized extracellular enzymes cleaving glycoside bonds in the molecules of dextran, pectic acid, and soluble starch. The maximal production of extracellular beta-galactosidase by B. adolescentis 91-BIM and 94-BIM at a rate of 0.08 and 0.03 U/mg h was observed during the exponential growth phase at 5 and 12 h of cultivation, respectively. The cultures of bifidobacteria retained 60-70% of beta-galactosidase and alpha-amylase activities after six months of storage. The bifidobacterium strains studied were resistant to amphotericin and aminoglycosides (gentamicin, kanamycin, and netromycin). The lactam antibiotics (ampicillin, benzylpenicillin, bicillin 3, bicillin 5, and carbenicillin), the preparations inhibiting protein synthesis at the level of ribosomes (lincomycin), RNA polymerase inhibitors (rifampin), cephalosporin, and Maxipime inhibited the growth of bifidobacteria. Rifampin, erythromycin, amphotericin, Maxipime, Fortum, doxycycline, levomycetin, streptomycin, and the aminoglycosides netromycin, gentamicin, and kanamycin did not have an effect on the growth of Lactobacillus sp., whereas semisynthetic derivatives of penicillin, carbenicillin and ampicillin, inhibited its growth as well as Oxamp and lincomycin. The lactam antibiotics benzylpenicillin, bicillin 3, and bicillin 5 inhibited the growth of lactic acid bacilli by 30-90%.     

The sensitivity to 12 antibiotics of 125 strains of Streptococcus group B isolated in a maternity home

Sensitivity of 125 strains of group B streptococci isolated from newborns, their mothers and personnel in a maternity home was studied with respect to 12 antibiotics: benzylpenicillin, ampicillin, methicillin, cephalotin, erythromycin, lincomycin, levomycetin (chloramphenicol), oxacillin, tetracycline, streptomycin, gentamicin and ristomycin. The method of serial dilutions in a solid medium was applied. All the strains were sensitive to ristomycin and erythromycin. The predominating number of the strains were sensitive to lincomycin, levomycetin and the beta-lactam antibiotics. Strains resistant or moderately resistant to benzylpenicillin, ampicillin, oxacillin, methicillin and cephalotin were detected. The majority of the strains were resistant to streptomycin, tetracycline and gentamicin. Multiple antibiotic resistance with 2-7 determinants was revealed in 11.2 per cent of the strains. The antibiotic sensitivity of the strains isolated from the newborns, their mothers and the personnel in the maternity home was on the whole similar or insignificantly differed.     

Production of hydrolases by lactic acid bacteria and bifidobacteria and their antibiotic resistance

It was demonstrated that bifidobacteria and lactic acid bacteria B. adolescentis and Lactobacillus sp. synthesized extracellular enzymes cleaving glycoside bonds in the molecules of dextran, pectic acid, and soluble starch. The maximal production of extracellular β-galactosidase by B. adolescentis 91-BIM and 94-BIM at a rate of 0.08 and 0.03 U/mg per h was observed during the exponential growth phase at 5 and 12 h of cultivation, respectively. The cultures of bifidobacteria retained 60–70% of β-galactosidase and α-amylase activities after six months of storage. The bifidobacterium strains studied were resistant to amphotericin and aminoglycosides (gentamicin, kanamycin, and netromycin). The lactam antibiotics (ampicillin, benzylpenicillin, bicillin 3, bicillin 5, and carbenicillin), the preparations inhibiting protein synthesis at the level of ribosomes (lincomycin), RNA polymerase inhibitors (rifampin), cephalosporin, and Maxipime inhibited the growth of bifidobacteria. Rifampin, erythromycin, amphotericin, Maxipime, Fortum, doxycycline, levomycetin, streptomycin, and the aminoglycosides netromycin, gentamicin, and kanamycin did not have an effect on the growth of Lactobacillus sp., whereas semisynthetic derivatives of penicillin, carbenicillin and ampicillin, inhibited its growth as well as Oxamp and lincomycin. The lactam antibiotics benzylpenicillin, bicillin 3, and bicillin 5 inhibited the growth of lactic acid bacilli by 30–90%.     

Sensitivity of bifidobacteria to antibacterial drugs

Twenty one strains of bifidobacteria belonging to various species were studied with respect to their sensitivity to antibacterial drugs most widely used in medical practice. The strains were isolated from practically healthy persons and from persons in contact with antibiotics in their production. It was found that sensitivity of the strains was the highest with respect to penicillins and tetracyclines. With respect to kanamycin, monomycin and levomycetin the strains were resistant. Strain differences in resistance to separate antibacterial drugs were observed. Increased streptomycin and tetracycline resistance of the strains isolated from the persons being for a prolonged period in contact with these antibiotics in their production, was stated.     

Determination of Antibiotic Susceptibility of Rickettsia by the Plaque Assay Technique

Plaque formation by various rickettsiae was completely inhibited by commercial antibiotic discs impregnated with tetracycline, chloramphenicol, nitrofurantoin, and erythromycin; partial inhibition was observed around discs containing nalidixic acid and sulfisoxazole, but no inhibition was seen around discs containing cephalothin, ampicillin, oxacillin, kanamycin, polymyxin B, streptomycin, or penicillin.     

Sensitivity of Yersinia enterocolitica to antibiotics]

Sensitivity of 33 foreign and 10 native strains of Y. enterocolitica to tetracycline, aminoglycosides, penicillins, levomycetin and polymyxin was studied. All the strains proved to be resistant to penicillin, oxacillin and ampicillin: they produced penicillinase. The level of resistance to penicillin did not always correlate with penicillin activity. The ability of the native strains to acquire R-factor in vitro from Coli bacteria was shown.     

Resistance to antibiotics and heavy metal salts of coagulase-positive staphylococci belonging to different biological types (ecovars)

A total of 189 strains of S. aureus isolated from cows, sheep, swines, poultry, monkeys, rabbits, foxes, and humans and 23 strains of S. intermedius isolated from minks and sables were studied. The staphylococci belonged to different biological types (according to the Hajek-Marsalek's scheme) and ecovars (according to the Meyer-Witte's scheme). The strains were studied with respect to their resistance to 10 antibiotics (benzylpenicillin, streptomycin, tetracycline, levomycetin, erythromycin, oleandomycin, neomycin, kanamycin, monomycin, and novobiocin), mercuric chloride and cadmium sulfate. As a whole the frequency of resistance to the above preparations among the staphylococci of the animal origin was not high. Differences in the frequency and range of the resistance between strains belonging to different biological types (ecovars) were shown. The highest number of the resistant cultures was detected among the strains of the biological type E (ecovar canis) and atypical strains of S. intermedius isolated from the minks. The least number of the resistant cultures was detected among the strains of the biological type C1 (ecovar bovis) isolated from the cows. It was found that almost all strains of S. intermedius were resistant to cadmium sulfate. This may be used as an additional characteristic of the species.     

Effect of hydroacridine derivatives on the sensitivity of polyresistant strains of Staphylococcus aureus and Escherichia coli to antibiotics]

Sensitivity of 4 clinical strains of Staph. aureus and E. coli to 13 hydroacridine derivatives and their combinations with antibiotics, such as benzylpenicillin, ampicillin, semi-synthetic penicillins, streptomycin, chloramphenicol, tetracycline, chlortetracycline, monomycin, oleandomycin and erythromycin was studied. The highest bacteriostatic effect was observed on the use of perhydroactidine derivatives with benzylpenicillin or ampicillin with respect to polyresistant penicillinase-producing strains of Staph. aureus, resistance of which to these antibiotics was decreased 250--1000 times. Under the effect of the above compounds the staphylococcal resistance to chloramphenicol, tetracycline, chlortetracycline, oleandomycine and erythromycin decreased 2--66 times. The combinations of hydroacridine with the antibiotics, except 10-amino-trans-syn-trans-perhydroacridine had no effect on the resistance of the E. coli strains. The results of the combined effect of the above substances were associated with their chemical nature, the bacterial type and possibly the character of the strain resistance.     

Antibiotic sensitivity and the characteristics of transmissive R plasmids in Shigella belonging to various species]

Sensitivity of 241 Shigella strains isolated from patients at various regions of the USSR in 1975--1978 was tested with respect to 14 antibiotics by the method of serial dilutions. 90.5 per cent of the isolates proved to be resistant to the antibacterial drugs and the greater part of 75.9 per cent of them had multiple resistance. The resistance of the Shigella was most pronounced and frequent with respect to tetracycline, streptomycin, levomycetin, as well as ampicillin and carbenicillin. Gentamicin, cephaloridin, polymyxin M, kanamycin, monomycin, neomycin and rifampicin were highly active against the Shigella. More than 50 per cent of the isolates were sensitive to levomycetin, ampicillin and carbenicillin. Differences in the frequency of the resistant strains and the spectrum of the antibiotic resistance of different Shigella subgroups (species) were observed. The study of 173 multiple resistant Shigella strains showed that about 67 per cent of the strains had a capacity for transduction of the resistance markers into the recipient cells of E. coli. The conjugative R-plasmids were most frequent in Sh. boydii and Sh. sonnei (95 and 95 per cent respectively), less frequent in Sh. flexneri and Sh. newcastle (68 and 53 per cent respectively) and least frequent in the mannitol negative Shigella (25 per cent). The capacity for transduction of R-plasmids in the strains carrying the determinants of resistance to 2 or 3 antibiotics was higher than in the strains carrying the determinant of resistance to one antibiotic. The clinical Shigella strains tested mainly had transmissive R-plasmids of fi--character (79 per cent).