The effects of three nonoxynol-9 preparations on vaginal flora and epithelium.
(25/1212)
To evaluate the effects of nonoxynol-9 (N-9) on the vaginal flora and epithelium, 48 women (16 in each group) were evaluated by use of quantitative vaginal cultures and colposcopy. at baseline and at 0.5, 4, 24, 48, and 72 h after insertion of one of three N-9 preparations (4% gel [Conceptrol], 3.5% gel [Advantage-24], or a 28% vaginal contraceptive film). The proportion positive for H2O2+ or H2O2- lactobacilli did not change significantly with any of the preparations, but lactobacilli concentrations decreased transiently. Both the proportion of women with Gardnerella vaginalis and the concentration of G. vaginalis decreased transiently. The proportion of women with Escherichia coli increased with the 4% gel, and the concentration increased with all preparations. The number with anaerobic gram-negative rods increased, although the concentrations decreased. Symptoms and colposcopic abnormalities were rare. Changes in levels of vaginal bacteria were transient after single applications of N-9, but adverse effects may be enhanced with frequent, chronic use. (+info)
Prevalence of resistance to MLS antibiotics in 20 European university hospitals participating in the European SENTRY surveillance programme. Sentry Participants Group.
(26/1212)
Macrolide, lincosamide and streptogramin (MLS) antibiotics are chemically distinct inhibitors of bacterial protein synthesis. Resistance to MLS antibiotics may be constitutive or inducible. The purpose of this study is to update our understanding of the prevalence of different forms of MLS resistance in Europe. The analysis of 3653 clinical pneumococcal, staphylococcal and enterococcal isolates exhibited an average percentage of 21.3% and 6.2% intermediate and high-level penicillin-resistant Streptococcus pneumoniae, 21.8% methicillin-resistant Staphylococcus aureus and 11% vancomycin-resistant Enterococcus faecium. Geographical differences in erythromycin and clindamycin resistance in isolates of S. pneumoniae and S. aureus strongly reflect geographical variations in susceptibility to penicillin and methicillin, respectively. A very narrow range of MICs was obtained with quinupristin/dalfopristin, with no S. pneumoniae, S. aureus and E. faecium isolate having an MIC of > 4 mg/L, indicating a possible role of quinupristin/dalfopristin in the treatment of infections by multi-resistant Gram-positive bacteria. (+info)
Enterococcus hirae vacuolar ATPase is expressed in response to pH as well as sodium.
(27/1212)
The Enterococcus hirae ntp operon encodes both a vacuolar ATPase, which transports Na+ as well as Li+, and the KtrII K+ transporter. A plasmid, in which the chloramphenicol acetyltransferase gene (CAT) was placed downstream of the ntp promoter, was introduced into a mutant totally defective in Na+ extrusion. The CAT activity of this transformant was increased preferentially by addition of NaCl, but not by LiCl, in the media or by elevating the medium pH, correlating well with the increase in amounts of the ATPase subunits observed by Western blotting. The physiological significance of these responses of the ntp promoter is discussed. (+info)
Indispensable glutamic acid residue-139 of NtpK proteolipid in the reaction of vacuolar Na(+)-translocating ATPase in Enterococcus hirae.
(28/1212)
Enterococcus hirae vacuolar ATPase catalyzes translocation of Na+ or Li+ coupled with ATP hydrolysis. It is suggested that the glutamic acid residue (Glu139) of NtpK proteolipid subunit of this multisubunit enzyme is the binding site of these ions for translocation. Here we established a complementation system for the ntpK gene with its deletion mutant, and found that the ATPase activity disappeared upon replacement of Glu139 by aspartic acid. The side-chain length of this acidic residue of NtpK is thus important for this ATPase reaction. (+info)
In vitro activities of linezolid against important gram-positive bacterial pathogens including vancomycin-resistant enterococci.
(29/1212)
The emergence of resistance in gram-positive bacteria has necessitated a search for new antimicrobial agents. Linezolid is an oxazolidinone, a new class of antibacterial agents with enhanced activity against pathogens. We compared the activity of linezolid to those of other antimicrobial agents against 3,945 clinical isolates. Linezolid demonstrated potent activity against all isolates tested. For all vancomycin-susceptible enterococci, staphylococci, and streptococci, the activity of linezolid was comparable to that of vancomycin. Against oxacillin-resistant staphylococci and vancomycin-resistant enterococci, linezolid was the most active agent tested. In summary, linezolid appears to be a promising new antimicrobial agent for the treatment of gram-positive infections. (+info)
Risk factors for acquisition of gentamicin-resistant enterococcal infection: a case-controlled study.
(30/1212)
High-level gentamicin-resistant enterococci present problems in the treatment of infected patients, especially as synergy between penicillin and gentamicin is lost. Previous studies have suggested various risk factors for the acquisition of these enterococci. A case-controlled study was performed on 17 patients infected with resistant enterococci and 26 infected with sensitive strains who attended a London hospital. The key risk factors for acquisition of infection with high-level gentamicin-resistant enterococci were found to be prior prolonged antibiotic treatment, use of five or more antibiotics, and the presence of a urinary catheter. It is proposed that infection control measures should be targeted at patients at higher risk. In addition, control of antibiotic usage in a hospital may help to prevent acquisition and spread of these organisms. (+info)
Health risks associated with unpasteurized goats' and ewes' milk on retail sale in England and Wales. A PHLS Dairy Products Working Group Study.
(31/1212)
A pilot study to determine the microbiological quality of unpasteurized milk from goats and ewes sampled from farm shops, health food shops, and other retail premises found that 47%, (47/100) of goats' and 50% (13/26) of ewes' milk samples failed the standards prescribed by the Dairy Products (Hygiene) Regulations 1995. In addition, Staphylococcus aureus, haemolytic streptococci or enterococci, were present in excess of 10(2) c.f.u./ml in 9 (7 %) 2 (2 %) and 19 (15%) samples, respectively. Salmonella, campylobacter, verocytotoxin-producing Escherichia coli O157:H7 and Listeria monocytogenes were not detected in the samples. At the time of purchase approximately half of the milk samples (58 %) were frozen, the rest were liquid. Farm outlets sold predominantly liquid milk, other retail premises sold a frozen product. The microbiological quality of goats' and ewes' milk, whether frozen or liquid, was not significantly different. Milk sold from farm shops was of lower quality than that from health food shops and other retail premises. In this pilot study most producers (92 %) supplied, and most retailers (76 %) sold unpasteurized goats' and ewes' milk that contained unacceptable levels of indicator organisms. The study was carried out during the winter when goats' milk production is reduced. The results indicate the need for a full representative study of unpasteurized goats' and ewes' milk on retail sale throughout the year. (+info)
Glycopeptide tolerance in bacteria causing endocarditis.
(32/1212)
Glycopeptides have been recommended as therapy for endocarditis. MICs and MBCs of vancomycin and teicoplanin were compared for 100 isolates from patients with proven bacterial endocarditis. MICs were generally lower for teicoplanin and tolerance to both agents was common. Almost all isolates of enterococci were tolerant to both glycopeptides. Among the streptococci, 78% were tolerant to teicoplanin and 57% to vancomycin. Similar findings were demonstrated for staphylococci. Although isolates appear sensitive to glycopeptides, bactericidal activity cannot always be predicted. If a glycopeptide is indicated for treatment of endocarditis, combination therapy with a suitable aminoglycoside should be considered unless MBC testing can be performed. (+info)