Abstract:
:The responses of 20 ampicillin-susceptible Haemophilus influenzae type b clinical isolates to the bactericidal action of ampicillin were studied by using a modified agar dilution plate count method. A well-defined paradoxical effect was observed in each of the 24-h killing curve patterns for 19 of the 20 isolates, the remaining isolate showing a less-well-defined but suggestive paradoxical effect after 48 h of ampicillin exposure. For each isolate, the lowest 24-h persister percentage representing maximum killing (paradoxical trough percentage) occurred over a narrow range of concentrations immediately above the MIC, with such paradoxical trough percentages for the 20 isolates ranging from greater than 0.1 to less than 0.001%. Three isolates selected to represent slow, intermediate, and rapid responses were investigated by repetition of 24-h studies and by determination of expanded killing curve patterns. Resultant agar dilution plate count killing curve patterns were found to be reproducible and strain dependent and served to characterize each isolate. The paradoxical effect became more distinct with the prolongation of ampicillin action. Maximum killing was again evident for a narrow range of ampicillin concentrations immediately above the MIC, with persister percentages rising rapidly over the next few ampicillin concentrations to peak at 1 to 2 log10 increments higher than trough percentages. Based on the broad range of responses observed for the 20 isolates, the consistent presence of the paradoxical effect, and the time-dependent nature of bactericidal action, we suggest that the MBC and MBC/MIC ratios are inadequate indices of bactericidal action and that the all-or-none concept of "antimicrobial tolerance" should be abandoned.
journal_name
Antimicrob Agents Chemotherjournal_title
Antimicrobial agents and chemotherapyauthors
Woolfrey BF,Gresser-Burns ME,Lally RTdoi
10.1128/aac.31.11.1711subject
Has Abstractpub_date
1987-11-01 00:00:00pages
1711-7issue
11eissn
0066-4804issn
1098-6596journal_volume
31pub_type
杂志文章abstract::The effects of binding and the bactericidal action of vancomycin on the arrangement and mobilities of cell wall polymers in Bacillus licheniformis were investigated by (15)N nuclear magnetic resonance spectroscopy. The bactericidal action of vancomycin led to reduced mobilities of cell wall teichoic acid and teichuron...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.14.5.695
更新日期:1978-11-01 00:00:00
abstract::CP-65,207 is a new parenteral penem antibiotic with a broad spectrum that includes gram-positive, gram-negative, and anaerobic microorganisms, with MICs for 90% (MIC90s) of the majority of 1,101 clinical pathogens tested being less than or equal to 1 microgram/ml. The compound was from 10- to 100-fold more active than...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.33.8.1160
更新日期:1989-08-01 00:00:00
abstract::Moxifloxacin (BAY12-8039) is a new 8-methoxyquinolone shown to be active against Mycobacterium tuberculosis in vitro. We tested moxifloxacin for activity in mice against M. tuberculosis CSU93, a highly virulent, recently isolated clinical strain. The MIC of moxifloxacin for the CSU93 strain was 0.25 microg/ml. The ser...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.43.1.85
更新日期:1999-01-01 00:00:00
abstract::Chromosomally mediated penicillin resistance in Neisseria gonorrhoeae occurs in part through alterations in penicillin-binding proteins (PBPs) and a decrease in outer membrane permeability. However, the genetic and molecular mechanisms of transformation of a penicillin-susceptible strain of N. gonorrhoeae to high-leve...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.46.3.769-777.2002
更新日期:2002-03-01 00:00:00
abstract::Aspergillus fumigatus is a leading cause of death in immunocompromised patients and a frequent colonizer of the respiratory tracts of asthma and cystic fibrosis (CF) patients. Biofilms enable bacteria and yeasts to persist in infections and can contribute to antimicrobial resistance. We investigated the ability of A. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00234-08
更新日期:2008-11-01 00:00:00
abstract::A total of 100 Streptococcus pneumoniae strains with various penicillin G susceptibilities, isolated in Barcelona, Spain, from different pediatric sources during 1983 and the first 4 months of 1984, were tested for susceptibility to tetracycline, chloramphenicol, erythromycin, clindamycin, vancomycin, and rifampin. Th...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.28.2.357
更新日期:1985-08-01 00:00:00
abstract::The activities of sparfloxacin, azithromycin, temafloxacin, and rifapentine against two virulent strains of the Mycobacterium avium complex isolated from patients with AIDS were evaluated in a model of intracellular infection and were compared with that of clarithromycin. Human monocyte-derived macrophages were infect...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.35.7.1356
更新日期:1991-07-01 00:00:00
abstract::The emergence of resistant strains among common and rare Candida species necessitates continuous monitoring of the in vitro susceptibilities of those isolates. We therefore assessed the in vitro activities of micafungin against 1,099 molecularly identified isolates belonging to 5 common and 20 rare Candida species by ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01027-16
更新日期:2016-09-23 00:00:00
abstract::The effects of caspofungin combined with amphotericin B were investigated with Candida glabrata. Although in vitro experiments showed an indifferent interaction, the combination regimen was the only therapeutic approach yielding organ sterilization in a murine candidemia model. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.49.6.2546-2549.2005
更新日期:2005-06-01 00:00:00
abstract::The production of Klebsiella pneumoniae carbapenemases (KPCs) by Enterobacteriaceae has become a significant problem in recent years. To identify factors that could predict isolation of KPC-producing K. pneumoniae (KPCKP) in clinical samples from hospitalized patients, we conducted a retrospective, matched (1:2) case-...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02373-13
更新日期:2014-06-01 00:00:00
abstract::Among hospitalized adults who received vancomycin for their skin and skin structure infection (SSSI), patients who experienced acute kidney injury (AKI) had considerably higher 30-day readmission rates. Nearly half of the observed 30-day readmissions were due to non-SSSI-related reasons, which is consistent with the p...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01268-20
更新日期:2020-09-21 00:00:00
abstract::The effect of monocytopenia and granulocytopenia on the outgrowth of Staphylococcus aureus as well as on antibiotic efficacy was studied in an experimental thigh infection in mice. Pretreatment with etoposide reduced monocyte numbers in blood to 14% and those of granulocytes to 54% at the time of infection. Monocytope...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.33.6.980
更新日期:1989-06-01 00:00:00
abstract::The effects on Staphylococcus aureus viability and beta-lactamase activity of concentrations that simulated those in human serum after a combined dose of 875 mg of amoxicillin and 125 mg of clavulanic acid were studied in an in vitro pharmacodynamic model. Six hours of preexposure to concentrations of the amoxicillin-...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.41.6.1403
更新日期:1997-06-01 00:00:00
abstract::Antibiotic therapy with penicillin, doxycycline, and ceftriaxone has proven to be effective for the treatment of Lyme borreliosis. In some patients, however, it was noticed that borreliae can survival in the tissues in spite of seemingly adequate therapy. For a better understanding of this phenomenon, we investigated ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.39.5.1127
更新日期:1995-05-01 00:00:00
abstract::The intestinal elimination of ciprofloxacin in the large bowel was studied in a rabbit model. Segments from the cecum, colon, and sigmoid colon along with their intact blood vessels were isolated and perfused, and their contents were collected over a 90-min period following the administration of a single parenteral do...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.40.1.11
更新日期:1996-01-01 00:00:00
abstract::RBx 11760, a bi-aryl oxazolidinone, was investigated for antibacterial activity against Gram-positive bacteria. The MIC90s of RBx 11760 and linezolid against Staphylococcus aureus were 2 and 4 mg/liter, against Staphylococcus epidermidis were 0.5 and 2 mg/liter, and against Enterococcus were 1 and 4 mg/liter, respecti...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00453-16
更新日期:2016-11-21 00:00:00
abstract::Nephrotoxicity was more marked in rats receiving isepamicin at midlight than at middark. And, the once-daily administration at middark induced a lesser degree of nephrotoxicity than the twice-daily injection, which indicates that the once-daily treatment therapy may have potential value in the clinical use of aminogly...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.37.9.2042
更新日期:1993-09-01 00:00:00
abstract::A sequential therapy of caspofungin (CAS) and fluconazole (FLC) administration for treatment of Candida albicans infection was investigated. Treatment with CAS followed by FLC was as effective as CAS treatment given alone for the same duration. Our data suggest that switching from CAS to FLC is a potentially explorabl...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.48.10.4056-4058.2004
更新日期:2004-10-01 00:00:00
abstract::Ga(3+) is a semimetal element that competes for the iron-binding sites of transporters and enzymes. We investigated the activity of gallium maltolate (GaM), an organic gallium salt with high solubility, against laboratory and clinical strains of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resista...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00700-09
更新日期:2010-01-01 00:00:00
abstract::Here we completely sequenced four mcr-1-haboring plasmids, isolated from two extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli and two carbapenemase-producing Klebsiella pneumoniae clinical isolates. The mcr-1-harboring plasmids from an E. coli sequence type 2448 (ST2448) isolate and two K. pneumoniae ST...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00550-16
更新日期:2016-06-20 00:00:00
abstract::Cytomegalovirus can cause debilitating and life-threatening disease in newborns infected in utero and immunocompromised individuals, including transplant recipients. RG7667 is a unique combination of two monoclonal antibodies that binds glycoprotein complexes on the surface of cytomegalovirus and inhibits its entry in...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1128/AAC.00523-15
更新日期:2015-08-01 00:00:00
abstract::When growing bacteria are exposed to bactericidal concentrations of antibiotics, the sensitivity of the bacteria to the antibiotic commonly decreases with time, and substantial fractions of the bacteria survive. Using Escherichia coli CAB1 and antibiotics of five different classes (ampicillin, ciprofloxacin, rifampin,...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.49.4.1483-1494.2005
更新日期:2005-04-01 00:00:00
abstract::Cyclacillin, a new aminosalicylic semisynthetic penicillin, was compared with amoxicillin for the therapy of acute bacterial maxillary sinusitis in 80 patients (ages, 12 to 70 years) in a prospective, double-blind, randomized clinical trial. Direct sinus aspirations for quantitative culture were done for all patients ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1128/aac.30.3.350
更新日期:1986-09-01 00:00:00
abstract::Chloramphenicol acetyltransferases specified by fi(-) (F fertility-noninhibiting) R factors were compared with those specified by the fi(+) R factors R1, 222, and R6-S. Three classes of enzyme were distinguished: class I was determined by group N fi(-) R factors and was indistinguishable from the enzyme determined by ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.3.1.99
更新日期:1973-01-01 00:00:00
abstract::The respiratory syncytial virus (RSV) L protein is a viral RNA-dependent RNA polymerase that contains multiple enzyme activities required for RSV replication. The RSV L inhibitors described in literature are limited by their cytotoxicity or the lack of RSV B subtype coverage. Here, we characterize a new RSV L inhibito...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02540-14
更新日期:2014-07-01 00:00:00
abstract::The DNA sequences of two plasmids carrying vanA, pVEF1 (39,626 bp) and pVEF2 (39,714 bp), were determined. Forty-three shared coding sequences were identified, and the only nucleotide difference was an 88-bp indel. A postsegregational killing system was identified. This system possibly explains the persistence of the ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00557-06
更新日期:2007-02-01 00:00:00
abstract::A new method for the analysis of serum chloramphenicol by reversed-phase, high-performance liquid chromatography (HPLC) is described. The method involves a preliminary extraction of 0.1 ml of serum with ethyl acetate containing an internal standard, chromatography with a reversed-phase C18 microparticulate column with...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.14.3.439
更新日期:1978-09-01 00:00:00
abstract::Carbapenem-resistant Acinetobacter baumannii is a major source of nosocomial infections worldwide and is mainly associated with the acquisition of OXA-type carbapenemases and, to a lesser extent, metallo-β-lactamases (MBLs). In this study, 82 nonepidemiologically related Acinetobacter strains carrying different types ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.03870-14
更新日期:2014-12-01 00:00:00
abstract::Placental transfer of the HIV protease inhibitor darunavir was investigated in 5 term human cotyledons perfused with darunavir (1,000 ng/ml) in the maternal to fetal direction. The mean (± the standard deviation [SD]) fetal transfer rate (FTR) (fetal/maternal concentration at steady state from 30 to 90 min) was 15.0%±...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.03184-14
更新日期:2014-09-01 00:00:00
abstract::The efficacy of a new class of drugs for Pneumocystis carinii pneumonitis was demonstrated. 566C80, a hydroxynaphthoquinone, administered orally in a dose of greater than or equal to 100 mg/kg of body weight per day prophylactically prevented P. carinii pneumonitis in 90% or more of rats, while all untreated control a...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.34.2.225
更新日期:1990-02-01 00:00:00