Abstract:
:Accurate antibiotic susceptibility testing is essential for successful tuberculosis treatment. Recent studies have highlighted the limitations of minimum inhibitory concentrations (MIC) based phenotypic susceptibility methods in detecting other aspects of antibiotic susceptibilities in bacteria. Duration and peak of antibiotic exposure, at or above the MIC required for killing the bacterial population, has emerged as another important factor for determining the antibiotic susceptibility. This is broadly defined as antibiotic tolerance. Antibiotic tolerance can further facilitate the emergence of antibiotic resistance. Currently there are limited methods to quantify antibiotic tolerance among clinical M. tuberculosis isolates. In this study, we develop a most-probable number (MPN) based minimum duration of killing (MDK) assay to quantify the spectrum of M. tuberculosis rifampicin susceptibility within subpopulations, based on time duration of rifampicin exposure required for killing the bacterial population. MDK90-99 and MDK99.99 defined as the minimum time duration of antibiotic exposure at or above MIC required for killing 90-99% and 99.99% of the initial (pre-treatment) bacterial population respectively. Results from the rifampicin MDK assay applied to 28 laboratory and clinical M. tuberculosis isolates showed that there is variation in rifampicin susceptibility among isolates. Rifampicin MDK99 / 99.99 time for isolates varied from less than 2 to 10 days. MDK was correlated with larger sub-populations of M. tuberculosis from clinical isolates that were rifampicin tolerant. Our study demonstrates the utility of MDK assays to measure the variation in antibiotic tolerance among clinical M. tuberculosis isolates and further expands clinically important aspects of antibiotic susceptibility testing.
journal_name
Antimicrob Agents Chemotherjournal_title
Antimicrobial agents and chemotherapyauthors
Vijay S,Nhung HN,Bao NLH,Thu DDA,Trieu LPT,Phu NH,Thwaites GE,Javid B,Thuong NTTdoi
10.1128/AAC.01439-20subject
Has Abstractpub_date
2020-11-30 00:00:00eissn
0066-4804issn
1098-6596pii
AAC.01439-20pub_type
杂志文章abstract::In the course of surveying for the carbapenem-hydrolyzing metallo-beta-lactamase gene bla(IMP) in pathogenic bacteria by the PCR method, we detected a gene encoding a variant metallo-beta-lactamase, designated IMP-3, which differed from IMP-1 by having low hydrolyzing activity for penicillins and carbapenems. PCR prod...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.44.8.2023-2027.2000
更新日期:2000-08-01 00:00:00
abstract::Acute kidney injury (AKI) occurs in a substantial proportion of critically ill patients receiving intravenous colistin. In the pharmacokinetic/toxicodynamic analysis reported here, the relationship of the occurrence of AKI to exposure to colistin and a number of potential patient factors was explored in 153 critically...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章,多中心研究
doi:10.1128/AAC.01367-17
更新日期:2017-10-24 00:00:00
abstract::The physicochemical constants and some structural parameters (topological, steric, and electronic) of eight third-generation monofluorate quinolones (six uncommercialized and two used clinically [ciprofloxacin and enrofloxacin]) were determined: pKa, intrinsic solubility (S0), chromatographic capacity factor, partitio...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.41.9.1996
更新日期:1997-09-01 00:00:00
abstract::The in vitro activity of the azasordarin GW 471558 was compared with those of amphotericin B, flucytosine, itraconazole, and ketoconazole against 177 clinical isolates of Candida spp. GW 471558 showed potent activity against Candida albicans, Candida glabrata, and Candida tropicalis, even against isolates with decreas...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.45.6.1905-1907.2001
更新日期:2001-06-01 00:00:00
abstract::Bactericidal activity in serum produced after administration of 1-g intravenous doses of cefoperazone, cefotaxime, ceftizoxime, and moxalactam was ascertained in six healthy subjects. The assay organisms were a strain of Staphylococcus aureus which was moderately susceptible to the drugs (MBC, 2 to 8 micrograms/ml) an...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.28.1.55
更新日期:1985-07-01 00:00:00
abstract::Colistin resistance, although uncommon, is increasingly being reported among Gram-negative clinical pathogens, and an understanding of its impact on the activity of antimicrobials is now evolving. We evaluated the potential for synergy of colistin plus trimethoprim, trimethoprim-sulfamethoxazole (1/19 ratio), or vanco...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.05996-11
更新日期:2012-09-01 00:00:00
abstract::Properties of a population of carbenicillin- and gentamicin-resistant, tobramycin-susceptible Pseudomonas aeruginosa at Veteran's Administration Hospital, Cincinnati, Ohio, have been followed during a 16-month period. As originally described, the strains were isolated from patients with urinary tract colonizations and...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.9.5.810
更新日期:1976-05-01 00:00:00
abstract::Isoxyl (ISO), a thiourea derivative that was successfully used for the clinical treatment of tuberculosis during the 1960s, is an inhibitor of the synthesis of oleic and mycolic acids in Mycobacterium tuberculosis. Its effect on oleic acid synthesis has been shown to be attributable to its inhibitory activity on the s...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00433-07
更新日期:2007-11-01 00:00:00
abstract::Alternate therapies are needed for treatment of secondary bacterial pneumonia following influenza. The immunomodulatory peptide P4 has shown promise in mouse models of primary pneumococcal infection. Mice infected with influenza virus and then challenged with Streptococcus pneumoniae were treated with a combination of...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00057-11
更新日期:2011-05-01 00:00:00
abstract::Invasive aspergillosis is an increasingly frequent opportunistic infection in immunocompromised patients. Only two agents, amphotericin B and itraconazole, are licensed for therapy. Itraconazole acts through inhibition of a P-450 enzyme undertaking sterol 14alpha demethylation. In vitro resistance in Aspergillus fumig...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.41.6.1364
更新日期:1997-06-01 00:00:00
abstract::Food for human consumption is screened widely for the presence of antibiotic-resistant bacteria to assess the potential for transfer of resistant bacteria to the general population. Here, we describe an Enterobacter cloacae complex isolated from imported seafood that encodes two carbapenemases on two distinct plasmids...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02338-18
更新日期:2019-05-24 00:00:00
abstract::An ultrasensitive assay utilizing high-pressure liquid chromatography and mass spectrometry detection was developed and validated for the quantification of the antiretrovirals atazanavir (ATV), darunavir (DRV), lopinavir (LPV), ritonavir (RTV), and efavirenz (EFV) in human mononuclear cell (MNC) extracts. The assay ut...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02551-13
更新日期:2014-05-01 00:00:00
abstract::An in vitro pharmacodynamic model was used to simulate the in vivo pharmacokinetics of clarithromycin and 14-hydroxyclarithromycin in order to generate time-kill curves for three clinical isolates of Haemophilus influenzae (isolates 2019, 91-183, and 1746). Representative concentrations in serum or lung tissue and the...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.38.9.2003
更新日期:1994-09-01 00:00:00
abstract::Twenty-four children with cancer and localized herpes zoster were randomized to receive either topical polyinosinic acid-polycytidylic acid [poly(I:C)] or a saline placebo. Solutions containing 1.0 or 2.5 mg of drug per ml were applied to the lesions every 3 h, seven times a day for 7 consecutive days. Serial, standar...
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.8.3.289
更新日期:1975-09-01 00:00:00
abstract::Leukocyte chemotaxis was inhibited 9.6% compared with control in the presence of 10 mug of gentamicin per ml and 10.5% when exposed to 20 mug of amikacin per ml. However, cells incubated with an injectable form of gentamicin, containing preservatives, were inhibited an additional 25.8% relative to cells incubated with...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.12.4.540
更新日期:1977-10-01 00:00:00
abstract::Chryseobacterium gleum (previously included in the Flavobacterium IIb species) is a gram-negative aerobe that is a source of nosocomial infections. An Ambler class B beta-lactamase gene was cloned and expressed in Escherichia coli from reference strain C. gleum CIP 103039 that had reduced susceptibility to expanded-sp...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.46.9.2791-2796.2002
更新日期:2002-09-01 00:00:00
abstract::Intestinal endogenous members of the family Enterobacteriaceae were eliminated in 12 human volunteers treated with 400 or 800 mg of oral norfloxacin per day for 5 days. No clones resistant to quinolone derivatives were isolated. Counts of aerotolerant streptococci were affected to various degrees, depending on their s...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.29.6.1047
更新日期:1986-06-01 00:00:00
abstract::Recently, the first Neisseria gonorrhoeae strain (H041) highly resistant to the expanded-spectrum cephalosporins (ESCs) ceftriaxone and cefixime, which are the last remaining options for first-line gonorrhea treatment, was isolated in Japan. Here, we confirm and characterize a second strain (F89) with high-level cefix...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.05760-11
更新日期:2012-03-01 00:00:00
abstract::The pharmacodynamic effects of metronidazole on Trichomonas vaginalis have been poorly characterized. The present in vitro study was performed to characterize the relationship between killing of trichomonads and metronidazole exposure (metronidazole concentration and time of exposure). Five laboratory strains and five...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.39.8.1848
更新日期:1995-08-01 00:00:00
abstract::4,4'-Isopropylidine-bis[2-isopropyl]phenol was found to possess antimicrobial activity against gram-positive bacteria and some fungi, whereas it had no effect on gram-negative organisms. The drug has a potent inhibitory action on the synthesis of cell wall mucopeptides of Bacillus subtilis by inhibiting the enzyme d-g...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.9.4.580
更新日期:1976-04-01 00:00:00
abstract::Biochemical variations accompanying the acquisition of ethambutol (EMB) resistance in a single-step mutant of Mycobacterium tuberculosis H37Ra were analyzed. Comparative analysis of phospholipids revealed a reduced content in the EMB-resistant strain, particularly in the cell membrane fraction. Significant alterations...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.34.9.1773
更新日期:1990-09-01 00:00:00
abstract::A novel algorithm designed for the screening of carbapenemase-producing Enterobacteriaceae (CPE), based on faropenem and temocillin disks, was compared to that of the Committee of the Antibiogram of the French Society of Microbiology (CA-SFM), which is based on ticarcillin-clavulanate, imipenem, and temocillin disks. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00796-17
更新日期:2017-07-25 00:00:00
abstract::The lfrA gene of Mycobacterium smegmatis encodes an efflux pump which mediates resistance to different fluoroquinolones, cationic dyes, and anthracyclines. The deletion of the lfrR gene, coding for a putative repressor and localized upstream of lfrA, increased the lfrA expression. In this study, reverse transcription-...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00656-06
更新日期:2006-12-01 00:00:00
abstract::A micellar formulation of amphotericin B (AmB) solubilized with poloxamer 188 was evaluated against an AmB Leishmania donovani-resistant line. A concave isobologram showed a synergistic effect of this association against promastigotes. This result was confirmed with amastigotes since the 50% effective concentration of...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.44.8.2190-2192.2000
更新日期:2000-08-01 00:00:00
abstract::Malaria control is hindered by the evolution and spread of resistance to antimalarials, necessitating multiple changes to drug policies over time. A comprehensive antimalarial drug resistance surveillance program is vital for detecting the potential emergence of resistance to antimalarials, including current artemisin...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01894-15
更新日期:2015-12-01 00:00:00
abstract::Remdesivir was recently approved by the Food and Drug Administration for the treatment of hospitalized patients with coronavirus disease 2019 (COVID-19). Remdesivir is the prodrug of an adenosine analogue that inhibits viral replication of several RNA virus families, including Coronaviridae Preclinical data in animal ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章,评审
doi:10.1128/AAC.01814-20
更新日期:2020-12-16 00:00:00
abstract::Defensins are small cationic bactericidal peptides present abundantly in the granules of polymorphonuclear neutrophils (PMNs). Human PMNs contain four defensins termed HNP-1 to HNP-4. We used a new assay system in agar plates, the radial diffusion assay, to evaluate the effects of human defensins against gram-positive...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.40.10.2280
更新日期:1996-10-01 00:00:00
abstract::Pseudomonas aeruginosa strains that produce metallo-beta-lactamases (MBLs) are becoming increasingly prevalent. We evaluated the epidemiological and microbiological characteristics of monomicrobial bloodstream infections caused by MBL-producing P. aeruginosa isolates, as well as the clinical outcomes in patients with ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.50.1.388-390.2006
更新日期:2006-01-01 00:00:00
abstract::We compared the activity of delavirdine (DLV) plus zidovudine (AZT) (n = 300) with that of AZT (n = 297) against human immunodeficiency virus type 1 in a randomized, double-blind, placebo-controlled trial. DLV exerted a transient antiviral effect, and mutations for resistance to DLV were found in more than 90% of subj...
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.44.11.3155-3157.2000
更新日期:2000-11-01 00:00:00
abstract::Staphylococcus epidermidis is one of the most frequent causes of device-associated infections, because it is known to cause biofilms that grow on catheters or other surgical implants. The persistent increasing resistance of S. epidermidis and other coagulase-negative staphylococci (CoNS) has driven the need for newer ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00504-13
更新日期:2013-10-01 00:00:00