Abstract:
:The MICs and minimum bactericidal concentrations (MBCs) for the biocides benzalkonium chloride and chlorhexidine were determined against 1,602 clinical isolates of Staphylococcus aureus. Both compounds showed unimodal MIC and MBC distributions (2 and 4 or 8 mg/liter, respectively) with no apparent subpopulation with reduced susceptibility. To investigate further, all isolates were screened for qac genes, and 39 of these also had the promoter region of the NorA multidrug-resistant (MDR) efflux pump sequenced. The presence of qacA, qacB, qacC, and qacG genes increased the mode MIC, but not MBC, to benzalkonium chloride, while only qacA and qacB increased the chlorhexidine mode MIC. Isolates with a wild-type norA promoter or mutations in the norA promoter had similar biocide MIC distributions; notably, not all clinical isolates with norA mutations were resistant to fluoroquinolones. In vitro efflux mutants could be readily selected with ethidium bromide and acriflavine. Multiple passages were necessary to select mutants with biocides, but these mutants showed phenotypes comparable to those of mutants selected by dyes. All mutants showed changes in the promoter region of norA, but these were distinct from this region of the clinical isolates. Still, none of the in vitro mutants displayed fitness defects in a killing assay in Galleria mellonella larvae. In conclusion, our data provide an in-depth comparative overview on efflux in S. aureus mutants and clinical isolates, showing also that plasmid-encoded efflux pumps did not affect bactericidal activity of biocides. In addition, current in vitro tests appear not to be suitable for predicting levels of resistance that are clinically relevant.
journal_name
Antimicrob Agents Chemotherjournal_title
Antimicrobial agents and chemotherapyauthors
Furi L,Ciusa ML,Knight D,Di Lorenzo V,Tocci N,Cirasola D,Aragones L,Coelho JR,Freitas AT,Marchi E,Moce L,Visa P,Northwood JB,Viti C,Borghi E,Orefici G,BIOHYPO Consortium.,Morrissey I,Oggioni MRdoi
10.1128/AAC.00498-13subject
Has Abstractpub_date
2013-08-01 00:00:00pages
3488-97issue
8eissn
0066-4804issn
1098-6596pii
AAC.00498-13journal_volume
57pub_type
杂志文章abstract::Treatment options are limited for implant-associated infections (IAI) that are mainly caused by biofilm-forming staphylococci. We report here on the activity of the serrulatane compound 8-hydroxyserrulat-14-en-19-oic acid (EN4), a diterpene isolated from the Australian plant Eremophila neglecta. EN4 elicited antimicro...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01735-12
更新日期:2013-01-01 00:00:00
abstract::Hydrophilic albumin microspheres are proposed as a new delivery system for amphotericin B (AMB; AMB microspheres). The acute toxicity of AMB microspheres was lower than that of the AMB-deoxycholate (AMB-Doc) reference formulation in hamsters. Lethal doses in healthy and infected animals were improved at least eight ti...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.48.9.3246-3252.2004
更新日期:2004-09-01 00:00:00
abstract::The discovery of quorum-sensing (QS) systems regulating antibiotic resistance and virulence factors (VFs) has afforded a novel opportunity to prevent bacterial pathogenicity. Dietary molecules have been demonstrated to attenuate QS circuits of bacteria. But, to our knowledge, no study exploring the potential of colost...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.03722-14
更新日期:2015-04-01 00:00:00
abstract::Daptomycin is an investigational lipopeptide antibiotic active against gram-positive organisms. The mechanism of action is unique, resulting in interference with cell membrane transport. The bactericidal activity of daptomycin was evaluated against glycopeptide-intermediate susceptible Staphylococcus aureus (GISA), va...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.45.2.454-459.2001
更新日期:2001-02-01 00:00:00
abstract::The motility of viable Trichomonas vaginalis organisms is readily demonstrable in a clinical wet mount or cultured specimens. We attempted to determine whether migration is a dynamic process such that the organisms move to avoid exposure to toxic antimicrobial agents. With the use of axenic cultures of T. vaginalis th...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.32.9.1323
更新日期:1988-09-01 00:00:00
abstract::A single Klebsiella pneumoniae strain isolated in a Bulgarian hospital was found to produce CTX-M-71, a new CTX-M variant characterized by one amino acid substitution from glycine to cysteine at position 238 in comparison to CTX-M-15. This exchange decreased the hydrolytic activity of the beta-lactamase for cefotaxime...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00461-09
更新日期:2009-10-01 00:00:00
abstract::Among the 7 most common UL97 mutations encountered in ganciclovir-resistant clinical cytomegalovirus isolates, the associated cyclopropavir cross-resistance varies from insignificant (L595S) to substantial (M460I and H520Q) as determined by recombinant phenotyping. Mutations M460I and H520Q were preferentially selecte...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01259-10
更新日期:2011-01-01 00:00:00
abstract::The objectives of this study were to investigate raltegravir transport across several blood-tissue barrier models and the potential interactions with drug efflux transporters. Raltegravir uptake, accumulation, and permeability were evaluated in vitro in (i) P-glycoprotein (P-gp), breast cancer resistance protein (BCRP...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.04594-14
更新日期:2015-05-01 00:00:00
abstract::Diabetic foot ulcer treatment currently focuses on targeting bacterial biofilms, while dismissing fungi. To investigate this, we used an in vitro biofilm model containing bacteria and fungi, reflective of the wound environment, to test the impact of antimicrobials. Here we showed that while monotreatment approaches in...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00672-17
更新日期:2017-08-24 00:00:00
abstract::The majority of clinical isolates of Moraxella catarrhalis produce beta-lactamase. The role of this enzyme in the phenomenon of indirect pathogenicity, in which a true pathogen such as Streptococcus pneumoniae is protected from the action of certain beta-lactam antibiotics, is well recognized. By using a simple contin...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.42.10.2521
更新日期:1998-10-01 00:00:00
abstract::Development of anthrax countermeasures that may be used concomitantly in a postexposure setting requires an understanding of the interaction between these products. Anthrax immune globulin intravenous (AIGIV) is a candidate immunotherapeutic that contains neutralizing antibodies against protective antigen (PA), a comp...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00460-13
更新日期:2013-11-01 00:00:00
abstract::The multiple-dose pharmacokinetics of amoxicillin (AM [administered twice daily in a 25-mg/kg of body weight intravenous dose]) in 17 preterm infants (11 males; gestational age, 29 +/- 1.9 weeks; birth weight, 1,175 +/- 278 g) were evaluated on day 3 of life. Blood samples were collected from an arterial catheter at 0...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.39.2.431
更新日期:1995-02-01 00:00:00
abstract::The mechanism of growth inhibition of Escherichia coli by thioglycerol was probed. The extent of growth inhibition depended on the ratio of thioglycerol to initial cell concentration. Exogenously added methionine and several methionine analogues reversed the inhibition of 2 to 40 mM thioglycerol. Exposure to thioglyce...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.24.6.860
更新日期:1983-12-01 00:00:00
abstract::Antibiotic treatment of lung infections may lead to the emergence of resistance in the gut flora. Appropriate dosing regimens could mitigate this adverse effect. In gnotobiotic rats harboring intestinal Escherichia coli and Enterococcus faecium populations, a lung infection by Klebsiella pneumoniae was instigated with...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01612-09
更新日期:2010-07-01 00:00:00
abstract::Enzyme-mediated immunoassay (EMIT) serum aminoglycoside assay results were accurate and precise and correlated well with radioimmunoassay, fluoroimmunoassay, and acetyltransferase and microbiological assay determinations. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.19.6.1064
更新日期:1981-06-01 00:00:00
abstract::A novel plasmid-mediated metallo-beta-lactamase (IMP-9) is described in seven isolates of Pseudomonas aeruginosa from Guangzhou, China, isolated in 2000. The gene was carried on a large (approximately 450-kb) IncP-2 conjugative plasmid. This is the first report of carriage of bla(IMP) genes on such large plasmids. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.50.1.355-358.2006
更新日期:2006-01-01 00:00:00
abstract::Streptomycin, the first antibiotic used in tuberculosis control programs, perturbs protein synthesis at the ribosome level. It is shown here that streptomycin resistance in some clinical isolates of Mycobacterium tuberculosis is associated either with missense mutations in the rpsL gene, which encodes ribosomal protei...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.38.2.238
更新日期:1994-02-01 00:00:00
abstract::9-Deoxy-Delta(9),Delta(12)-13,14-dihydro-prostaglandin D(2) (Delta(12)-PGJ(2)), a natural cyclopentenone metabolite of prostaglandin D(2), is shown to possess therapeutic efficacy against influenza A virus A/PR8/34 (H1N1) infection in vitro and in vivo. The results indicate that the antiviral activity is associated wi...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.44.1.200-204.2000
更新日期:2000-01-01 00:00:00
abstract::Antimicrobial lock solutions are important for prevention of microbial colonization and infection of long-term central venous catheters. We investigated the efficacy and safety of a novel antibiotic-free lock solution formed from gas plasma-activated disinfectant (PAD). Using a luminal biofilm model, viable cells of m...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00744-18
更新日期:2018-07-27 00:00:00
abstract::High-performance liquid chromatography was used to determine the penetration of 19 antimicrobial agents into human polymorphonuclear leukocytes. The ratios of the intracellular concentration to the extracellular concentration of ampicillin, piperacillin, cefazolin, ceftizoxime, cefpimizole, and ceftazidime were all le...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.31.12.1904
更新日期:1987-12-01 00:00:00
abstract::The penicillin-binding proteins (PBPs) of helical (log-phase) Helicobacter pylori ATCC 43579 were identified by using biotinylated ampicillin. The major PBPs had apparent molecular masses of 47, 60, 63, and 66 kDa; an additional minor PBP of 95 to 100 kDa was also detected. The relative affinities of various beta-lact...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.43.11.2702
更新日期:1999-11-01 00:00:00
abstract::The interaction between four fluoroquinolones (ciprofloxacin, norfloxacin, pefloxacin, and ofloxacin) and biofilms of Pseudomonas aeruginosa in wells of microtiter plates and on segments of vascular catheters were studied in an in vitro model of vascular catheter colonization. Subinhibitory concentrations (one-half, o...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.39.10.2262
更新日期:1995-10-01 00:00:00
abstract::Miconazole, a broad-spectrum antimycotic agent with some antibacterial activity, has recently become available for experimental parenteral use in the United States. Its efficacy as an anticandidal drug was tested in adult Wistar rats. A previously established infectious dose of 5 x 10(6)Candida albicans was intravenou...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.13.2.321
更新日期:1978-02-01 00:00:00
abstract::Morphological heterogeneity of Aspergillus terreus cultures was observed during continued cultivation of amphotericin B (AMB)-resistant isolates on drug-free medium. Outgrowth leads to the emergence of multiple sectors that might result from increased growth rates at drug-free conditions. We evaluated the differences ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00755-17
更新日期:2017-11-22 00:00:00
abstract::The effects of multiple-dose administration of tenofovir disoproxil fumarate (TDF) on the pharmacokinetics of morinidazole (MOR) were compared in healthy subjects. MOR exposure was similar, with an area under the curve from 0 h to infinity (AUC0-∞) treatment ratio for MOR+TDF/MOR of 1.01 (90% confidence interval, 0.97...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02067-19
更新日期:2020-04-21 00:00:00
abstract::Clarithromycin is compared with clindamycin for single-dose prophylaxis of streptococcal endocarditis in rats. Human-like kinetics of the two antibiotics prevented endocarditis in animals challenged with both small and large amounts of bacterial inocula. Clarithromycin was marginally superior to clindamycin against sm...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.40.3.809
更新日期:1996-03-01 00:00:00
abstract::Monotherapy with isoniazid or amikacin or clarithromycin or combinations of two of these drugs showed nil to modest therapeutic activity in beige mice infected with Mycobacterium avium. However, the combination of all three, isoniazid-amikacin-clarithromycin, markedly reduced CFUs in both spleens and lungs after 91 da...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.42.3.712
更新日期:1998-03-01 00:00:00
abstract::Patterns of susceptibility of 45 Proteus penneri clinical isolates to 14 antimicrobial agents were evaluated by a macrobroth dilution method. All strains were highly susceptible to ceftizoxime, ceftazidime, moxalactam, cefoxitin, gentamicin, tobramycin, netilmicin, and, with few exceptions, to amikacin, piperacillin, ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.26.3.419
更新日期:1984-09-01 00:00:00
abstract::Human cytomegalovirus (HCMV) infection is usually benign in healthy individuals but can cause life-threatening disease in those with compromised immune systems. Approved drugs available to treat HCMV disease, including ganciclovir, cidofovir, and foscarnet, have significant toxicities that limit their use in certain p...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00382-16
更新日期:2016-07-22 00:00:00
abstract::We characterized the stability of a plasmid pCP53-mcr1_3 encoding mcr-1 and mcr-3.19 with and without colistin exposure during cultural passages via S1-pulsed-field gel electrophoresis (PFGE) and nanopore MinION sequencing. Both mcr-1 and mcr-3.19 were missing in certain subclones, mediated by genetic excision (ISApl1...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01002-19
更新日期:2019-08-23 00:00:00