Abstract:
:We investigated the impact of low-level resistance to fluoroquinolones on the bactericidal activity of ciprofloxacin in a murine model of urinary tract infection. The susceptible Escherichia coli strain CFT073 (ciprofloxacin MIC [CIP MIC] of 0.008 microg/ml) was compared to its transconjugants harboring qnrA1 or qnrS1 and to an S83L gyrA mutant. The three derivatives showed similar low-level resistance to fluoroquinolones (CIP MICs, 0.25 to 0.5 microg/ml). Bactericidal activity measured in vitro after 1, 3, and 6 h of exposure to 0.5 microg/ml of ciprofloxacin was significantly lower for the derivative strains (P < 0.01). In the murine model of urinary tract infection (at least 45 mice inoculated per strain), mice were treated with a ciprofloxacin regimen of 2.5 mg/kg, given subcutaneously twice daily for 2 days. In mice infected with the susceptible strain, ciprofloxacin significantly decreased viable bacterial counts (log10 CFU/g of tissue) in the bladder (4.2 +/- 0.5 versus 5.5 +/- 1.3; P = 0.001) and in the kidney (3.6 +/- 0.8 versus 5.0 +/- 1.1; P = 0.003) compared with those of untreated mice. In contrast, no significant decrease in viable bacterial counts was observed with any of the three derivative strains. The area under the concentration-time curve from 0 to 24 h/MIC and the maximum concentration of drug in serum/MIC ratios measured in plasma were indeed equal to 827 and 147, respectively, for the parental strain, and only 12.4 to 24.8 and 2.2 to 4.4, respectively, for the derivative strains. In conclusion, low-level resistance to fluoroquinolones conferred by a qnr gene is associated with decreased bactericidal activity of ciprofloxacin, similar to that obtained with a gyrA mutation.
journal_name
Antimicrob Agents Chemotherjournal_title
Antimicrobial agents and chemotherapyauthors
Allou N,Cambau E,Massias L,Chau F,Fantin Bdoi
10.1128/AAC.01664-08subject
Has Abstractpub_date
2009-10-01 00:00:00pages
4292-7issue
10eissn
0066-4804issn
1098-6596pii
AAC.01664-08journal_volume
53pub_type
杂志文章abstract::The single- and multiple-dose pharmacokinetics of and tolerability to a new microfluidized suspension of atovaquone were studied in human immunodeficiency virus-seropositive patients with CD4 counts of < or = 200 cells per mm3 in order to define a dosing regimen for the treatment of Pneumocystis carinii pneumonia. Thi...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 临床试验,杂志文章
doi:10.1128/AAC.40.3.556
更新日期:1996-03-01 00:00:00
abstract::Rates of metallo-beta-lactamase and 16S rRNA methylase production were investigated in 51 imipenem-resistant Pseudomonas aeruginosa clinical isolates collected from hospitals in São Paulo, Brazil. Of them, 57% and 75% produced SPM-1 and RmtD, respectively. Of note, 51% produced both enzymes, suggesting that their copr...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00443-07
更新日期:2007-09-01 00:00:00
abstract::Pharmacokinetic parameters were calculated from intravenous data based upon a two-compartment open model. These parameters were subsequently used to determine the absorption rates and bioavailability of cephradine administered intramuscularly and orally. The results indicate that cephradine obeys dose-independent kine...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.10.2.283
更新日期:1976-08-01 00:00:00
abstract::The antibacterial activity of octenidine dihydrochloride (WIN 41464-2) against intact preformed in vitro plaques of four indigenous oral plaque-forming microorganisms, Streptococcus mutans, Streptococcus sanguis, Actinomyces viscosus, and Actinomyces naeslundii, was studied. Both absolute (plaque bactericidal index) a...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.23.3.379
更新日期:1983-03-01 00:00:00
abstract::SCY-078 is an orally active antifungal whose target is the β-(1,3)-d-glucan synthase (GS). We evaluated the spontaneous emergence of SCY-078-resistant Candida glabrata isolates following drug exposure in vitro Resistant isolates were analyzed using broth microdilution methodology and FKS sequencing. The kinetic inhibi...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00833-17
更新日期:2017-08-24 00:00:00
abstract::Using a rabbit model of methicillin-resistant Staphylococcus aureus knee-prosthesis infection, we studied the efficacy of teicoplanin cement alone or in combination with systemic intramuscular (i.m.) injections of teicoplanin. Seven days after infection, surgical debridement and removal of the infected prostheses were...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.47.10.3365-3367.2003
更新日期:2003-10-01 00:00:00
abstract::The fluoroquinolone antimicrobial drug danofloxacin was administered to sheep intravenously (i.v.) and intramuscularly (i.m.) at a dose of 1.25 mg/kg of body weight in a two-period crossover study. The pharmacokinetic properties of danofloxacin in serum, inflamed tissue cage fluid (exudate), and noninflamed tissue cag...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.47.2.626-635.2003
更新日期:2003-02-01 00:00:00
abstract::The 50% inhibitory concentration (IC50s) of benflumetol (range, 12.5 to 240 nM; mean, 55.1 nM) for 158 Senegalese isolates were evaluated. Ten isolates (6%) showed decreased susceptibility to benflumetol. Benflumetol was slightly more potent against chloroquine-resistant isolates (P < 0.025). No correlation or weak co...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.43.2.418
更新日期:1999-02-01 00:00:00
abstract::A dipeptide lantibiotic, named Smb, in Streptococcus mutans GS5 was characterized by molecular genetic approaches. The Smb biosynthesis gene locus is encoded by a 9.5-kb region of chromosomal DNA and consists of seven genes in the order smbM1, -T, -F, -M2, -G, -A, -B. This operon is not present in some other strains o...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.49.2.541-548.2005
更新日期:2005-02-01 00:00:00
abstract::The small-colony-variant (SCV) phenotype of Staphylococcus aureus has been associated with difficult-to-treat infections, reduced antimicrobial susceptibility, and intracellular persistence. This study represents a detailed intra- and extracellular investigation of a clinical wild-type (WT) S. aureus strain and its co...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00205-10
更新日期:2011-04-01 00:00:00
abstract::Many Pseudomonas aeruginosa isolates from the airways of patients with cystic fibrosis (CF) are sensitive to antibiotics in susceptibility testing, but eradication of the infection is difficult. The main reason is the biofilm formation in the airways of patients with CF. The pharmacokinetics (PKs) and pharmacodynamics...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.06486-11
更新日期:2012-05-01 00:00:00
abstract::Induction of the cloned ampC Citrobacter freundii beta-lactamase in Escherichia coli by 6-aminopenicillanic acid was prevented by periplasmic TEM beta-lactamase in the same cell. In contrast, cytoplasmic TEM beta-lactamase did not prevent induction. This result implies that entry of the beta-lactam into the cytoplasm ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.34.12.2429
更新日期:1990-12-01 00:00:00
abstract::The MICs of three new antimicrobial agents of different classes, U-70138F, roxithromycin (RU 965), and ofloxacin (ORF 18489), versus Chlamydia trachomatis in McCoy cell cultures were 0.25, 0.8, and 1.0 microgram/ml, respectively. For each test drug, the MIC and MBC were identical or were within 1 dilution of one anoth...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.30.5.806
更新日期:1986-11-01 00:00:00
abstract::Deciphering the mode of action (MOA) of new antibiotics discovered through phenotypic screening is of increasing importance. Metabolomics offers a potentially rapid and cost-effective means of identifying modes of action of drugs whose effects are mediated through changes in metabolism. Metabolomics techniques also co...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02109-15
更新日期:2016-03-25 00:00:00
abstract::The efficacy of single-dose therapy with 3 g of cephalexin was evaluated in 129 women with symptoms of acute uncomplicated lower urinary tract infections. Of 91 patients with significant bacteriuria, 61 (67%) were cured of their original infection; this was similar to the 54 to 79% cure rates reported in unselected po...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.29.3.383
更新日期:1986-03-01 00:00:00
abstract::Echinocandins are important in the prevention and treatment of invasive candidiasis but limited by current dosing regimens that include daily intravenous administration. The novel echinocandin CD101 has a prolonged half-life of approximately 130 h in humans, making it possible to design once-weekly dosing strategies. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02154-17
更新日期:2018-01-25 00:00:00
abstract::Cyclic phosphate derivative of DHPG, 2'-nor-cGMP [9-[(2-hydroxy-1,3,2-dioxaphosphorinan-5-yl)oxymethyl]-guani ne phosphate-oxide] was evaluated for activity against guinea pig cytomegalovirus (GPCMV) infection in cultured guinea pig embryo cells and in guinea pigs. By virus yield reduction and plaque reduction assays,...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.33.9.1563
更新日期:1989-09-01 00:00:00
abstract::Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory Standards reference agar dilution method with supplemented brucella blood agar and an inoculum of 10(5) CFU/spot. Comparative antimicrobials tested i...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.43.9.2231
更新日期:1999-09-01 00:00:00
abstract::Penetration of linezolid into bone and joint tissues was studied by high-performance liquid chromatography in 13 patients suffering from implant-associated infections with methicillin-resistant staphylococci. Mean concentrations of linezolid in infected tissues were greater than 10 mg/liter in a sampling time range of...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 临床试验,杂志文章
doi:10.1128/aac.47.12.3964-3966.2003
更新日期:2003-12-01 00:00:00
abstract::Levels of roxithromycin in serum and tissue were investigated in 29 subjects undergoing tonsillectomy. A total of 13 subjects received a single oral dose of 300 mg, and 16 received four oral doses 12 h apart as follows: a 300-mg loading dose followed by three 150-mg doses. Measurable levels of roxithromycin were prese...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.32.9.1461
更新日期:1988-09-01 00:00:00
abstract::Cladosporium trichoides and Sporothrix schenckii are fungi known to be pathogenic for man. No effective chemotherapy is available for cladosporiosis, and systemic sporotrichosis can be very resistant to antifungal chemotherapy. Experimental infections of mice with these fungi resembled their respective infections in m...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.3.1.95
更新日期:1973-01-01 00:00:00
abstract::The apparent body clearance of chloramphenicol was investigated in 21 hospitalized adult patients on 27 occasions. Apparent body clearance was found to be significantly lower (1.99 +/- 1.49 ml/min per kg) in patients with total serum bilirubin concentrations of >1.5 mg/100 ml than in patients with serum bilirubin conc...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.15.5.651
更新日期:1979-05-01 00:00:00
abstract::β-Lactams are often used to treat Helicobacter cinaedi infections; however, the mechanism underlying β-lactam resistance is unknown. In this study, we investigated β-lactam resistance in an H. cinaedi strain, MRY12-0051 (MICs of amoxicillin [AMX] and ceftriaxone [CRO], 32 and 128 μg/ml; obtained from human feces). Bas...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02036-17
更新日期:2018-01-25 00:00:00
abstract::Bacteriophage therapy is a promising alternative treatment to antibiotics, as it has been documented to be efficacious against multidrug-resistant bacteria with minimal side effects. Several groups have demonstrated the efficacy of phage suspension in vivo to treat lung infections using intranasal delivery; however, p...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01714-17
更新日期:2018-01-25 00:00:00
abstract::To compare the effects of four antimicrobial peptides (MUC7 12-mer, histatin 12-mer, cathelicidin KR20, and a peptide containing lactoferricin amino acids 1 to 11) on the yeast Saccharomyces cerevisiae, we employed a genomewide fitness screen of combined collections of mutants with homozygous deletions of nonessential...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01439-12
更新日期:2013-02-01 00:00:00
abstract::Arylimidamides (AIAs) have been shown to have considerable biological activity against intracellular pathogens, includingTrypanosoma cruzi, which causes Chagas disease. In the present study, the activities of 12 novel bis-AIAs and 2 mono-AIAs against different strains ofT. cruziin vitroandin vivowere analyzed. The mos...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01667-15
更新日期:2016-03-25 00:00:00
abstract::The treatment of woodchuck hepatitis virus infections with 1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-iodocytosine (FIAC) and 1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-methyluracil (FMAU), given intraperitoneally, caused complete and permanent decrease of serum virus endogenous DNA polymerase and viral DN...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.34.3.473
更新日期:1990-03-01 00:00:00
abstract::INX-08189 is an aryl-phosphoramidate of 6-O-methyl-2'-C-methyl guanosine. INX-08189 was highly potent in replicon assays, with a 50% effective concentration of 10±6 nM against hepatitis C genotype 1b at 72 h. The inhibitory effect on viral replication was rapid, with a 50% effective concentration (EC50) of 35±8 nM at ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01335-10
更新日期:2011-05-01 00:00:00
abstract::The adaptive resistance of Pseudomonas aeruginosa to aminoglycosides is known to occur during chronic lung infections in cystic fibrosis patients in response to nonlethal concentrations of aminoglycosides. Not only is it difficult to achieve high levels of drug throughout the dehydrated mucus in the lung, but also ste...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00935-10
更新日期:2011-05-01 00:00:00
abstract::Children and adolescents with acute myeloid leukemia (AML) are at risk of life-threatening bacterial infections, especially with viridans group streptococci. Primary antibacterial prophylaxis with vancomycin-based regimens reduces this risk but might increase the risks of renal or liver toxicity or Clostridium diffici...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01838-17
更新日期:2018-02-23 00:00:00