Sensitivity of the main causative agents of gas gangrene to currently available antibacterial drugs

Sensitivity of the main microbial species causing gas gangrene to 21 antibacterial drugs was studied. The pathogens included 28 strains of Clostridium perfringens, 21 strains of C. oedematiens, 31 strains of C. septicum and 19 strains of C. histolyticum. Antibiotics having a bactericidal effect on the Clostridia were determined. The findings of the study were indicative of a variety of the antibiotic sensitivity spectra of the Clostridium spp., which accentuated the importance of antibiotic sensitivity assay in every particular case of gas gangrene.     

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.     

Sensitivity of Corynebacterium diphtheriae isolated in Saint-Petersburg to antibacterial drugs]

One hundred and thirty strains of Corynebacterium diphtheriae isolated in St. Petersburg (42 toxigenic and 88 nontoxigenic) were tested with the method of serial dilutions in solid media for their susceptibility to 20 antibacterial drugs. The MICs of the drugs for the isolates ranged from < or = 0.015 to > or = 32.0 micrograms/ml. 13 per cent of the isolates was resistant at least to one antibacterial drug. The isolates resistant to erythromycin (11.5 per cent), lincomycin (11.5 per cent) and trimethoprim (8.5 per cent) were most frequent. 3 isolates (2.3 per cent) had multiple resistance to 8 drugs: benzylpenicillin, ampicillin, oxacillin, chloramphenicol, erythromycin, lincomycin, trimethoprim, and nitroxolin. No significant differences in the susceptibility of the toxigenic and nontoxigenic strains of C. diphtheriae were detected. Gentamicin, rifampicin, tetracycline, doxycycline and pefloxacin were the most active antibiotics.     

Sensitivity spectrum of Francisella tularensis to antibiotics and synthetic antibacterial drugs

Sensitivity of 6 F. tularensis strains to 57 antibiotics and synthetic antibacterial drugs was studied. It was shown that the strains were highly sensitive to aminoglycosides, tetracyclines, anzamycins, quinolones, chloramphenicol, nitrofurantoin, nitroxoline, novobiocin and fusidin and resistant to penicillins, cephalosporins, polypeptides, vancomycin and sulfanylamides. The interrace differences in F. tularensis could be detected only by sensitivity to erythromycin, oleandomycin and spiramycin. There was observed no cross resistance to streptomycin and other aminoglycosides in F. tularensis. Assay of F. tularensis sensitivity to antibacterial drugs of various groups with the rapid photometric procedure and the agar diffusion method revealed that the results were highly comparable.     

Comparative responses of Pseudomonas stutzeri and Pseudomonas aeruginosa to antibacterial agents

The sensitivity of six strains of Pseudomonas stutzeri (NCIMB 568, 10783, 11358, 11359, JM 302, JM 375) to cationic antiseptics, mercury compounds, the parabens, phenolics, EDTA and various antibiotics was compared with Pseudomonas aeruginosa NCIMB 8626. All Ps. stutzeri strains were highly sensitive to chlorhexidine diacetate, organomercurials and triclosan, but rather less so to quarternary ammonium compounds (QACs). They were also sensitive to other biocidal agents and more sensitive to many antibiotics than the strain of Ps. aeruginosa. There was little correlation between uptake of chlorhexidine diacetate or cetylpyridinium chloride by dense suspensions of organisms, leakage of intracellular constituents and loss of cell viability.     

Sensitivity of Pseudomonas aeruginosa to Normal Serum and to Polymyxin

Strains of Pseudomonas aeruginosa isolated from clinical material were very variable in their sensitivity to the bactericidal action of normal serum mediated by the complement system. Fifty per cent killing end points ranged from 0.015 ml to greater than 0.4 ml. Most of the strains with relatively greater sensitivity to serum were isolated from patients with cystic fibrosis. Immunization of rabbits resulted in antisera with enhanced levels of bactericidal antibody, except with one strain which was resistant to the bactericidal action of normal serum and antiserum. When P. aeruginosa was cultivated at 41 C instead of at 37 C, it was significantly more sensitive to serum and to several antibiotics, thereby implicating fever as a host defense mechanism in Pseudomonas infections. In contrast to their heterogeneity to serum bactericidal activity, the strains were relatively homogeneous in their sensitivity to polymyxin, with no apparent association between their sensitivity to the two antimicrobial agents.     

Sensitivity of Escherichia coli O157:H7, a pathogen of hemorrhagic colitis, to antibacterial drugs]

Antibioticograms of enterohemorrhagic strains of serogroup O157 Escherichia coli isolated in the Russian Federation and Japan were comparatively studied. Strains with multiple drug resistance were detected. The main biochemical characteristics of the isolates were investigated. Significant differences in susceptibility spectra of the isolates and in their fermentative properties were revealed.     

Sensitivity of Pseudomonas mallei to sulfanilamide combinations in vitro

It was shown that 9 strains of P. mallei were sensitive to sulfanilamides and their combinations with trimethoprim: sulfamonomethoxine + trimethoprim (2.5:1), sulfamethoxazole + trimethoprim (5:1) and sulfazin + trimethoprim (2.5:1 and 5:1). In regard to multiple lowering of the minimum bactericidal concentration of both drugs the combinations of sulfazin with trimethoprim (5:1 or 2.5:1) and sulfamethoxazole with trimethoprim (5:1) or biseptol proved to be the most active. The activity of the sulfamonomethoxine combination with trimethoprim (sulfate) was lower.     

Pyocin Sensitivity of Pseudomonas Species

Only the fluorescent pseudomonads, Pseudomonas aeruginosa, P. putida, and P. fluorescens, were sensitive to pyocins produced from P. aeruginosa.     

Taking inventory: antibacterial agents currently at or beyond phase 1

At least 18 antibacterial agents are currently undergoing clinical trials for the treatment of infections caused by susceptible and resistant bacteria. The beta-lactam class includes new parenteral carbapenems and cephalosporins with varying spectra of activities. The glycopeptides are antibiotics with in vitro activity primarily against Gram-positive bacteria, including multi-resistant strains. Three quinolones are being investigated for use against a variety of Gram-positive and respiratory Gram-negative organisms. Several other classes of antibacterial agents currently in clinical trials are represented by a glycolipodepsipeptide, a dihydrofolate reductase inhibitor, an oxazolidinone, two peptide antibiotics, a glycylcycline, and a peptide deformylase inhibitor, a member of a new antibacterial class.     

葡萄球菌临床分离株对抗生素的药物敏感性

目的 了解天津8家三级甲等医院葡萄球菌临床分离株对常用抗生素的耐药情况和趋势。方法 收集天津市8所医院葡萄球菌临床株,用纸片扩散法进行药物敏感性测定。结果 2001～2002年分离的葡萄球菌临床株490株。金黄色葡萄球菌319株,MRSA占51.7%;凝固酶阴性葡萄球菌171株,MRCNS占65.6%。其中一医院2002～2003年分离的葡萄球菌临床株共103株.金黄色葡萄球菌81株,MRSA占%;凝固酶阴性葡萄球菌22株,MRCNS占72.84%;未发现万古霉素耐药株。结论 葡萄球菌的标本来源主要是痰培养和尿培养。MRSA的分离率与我国其他地区的数据相似。万古霉素在该地区仍然是最有效的治疗葡萄球菌感染的抗菌药物。     

Moving goalposts--regulatory oversight of antibacterial drugs

Is uncertainty concerning the regulation of antimicrobial drug trials stifling investment in infectious disease treatments? Here, experts from a large pharma company and a biotech firm provide their perspectives.     

Sensitivity to antibacterial preparations of the pathogenic staphylococci isolated from carriers]

After discontinuation of the use of antibiotics for sanation of the carriers of pathogenic staphylococci among the staff of a maternity unit, the number of the strains resistant to penicillin, streptomycin, chlortetracycline, tetracycline, levomycetin, erythromycin, monomycin and neomycin decreased 1.3, 2.9, 10,4.3,5.5,1.5,3.9 and 2.4 times respectively. The differences were statistically reliable. The causes of the antibiotic resistance decrease require further investigation.     

Sensitivity of fungi of the genus Candida to antifungal drugs

Seventy two Candida strains isolated from patients with candidiosis of the oral mucosa were studied with respect to their sensitivity to nystatin, levorin, decamine, ethonium, sanguiritrin and clotrimazole. At concentrations of 0.5 to 5 micrograms/ml all the Candida species i.e. C. albicans, C. tropicalis, C. krusei and C. quilliermondii were highly sensitive to clotrimazole. Fungistatic action of levorin, nystatin and sanguiritrin was observed in 91, 67 and 38 per cent of the strains respectively. The Candida strains were resistant to decamine and ethonium used in the above concentrations.