Abstract:
:Changes in plasmid DNA supercoiling were measured following treatment of Escherichia coli cells, carrying topoisomerase mutations, with the quinolone ciprofloxacin. In quinolone-susceptible cells (top+ gyr+) as well as in topA mutants and in gyrB mutants, plasmid DNA was relaxed after the addition of ciprofloxacin. In cells partially resistant to quinolones, low ciprofloxacin levels led to an increase in negative superhelicity of plasmid DNA, whereas at higher ciprofloxacin concentrations, DNA became relaxed. Cells exhibiting partial resistance to quinolones carried either a gyrA mutation alone or a combination of gyrA and gyrB mutations. Moreover, they showed a reduction in gyrase activity, indicated by the supercoiling of a reporter plasmid. Therefore, we conclude that a low level of quinolone action and a DNA with a lower-than-normal level of superhelicity are the two essential conditions for obtaining a ciprofloxacin-promoted increase in plasmid DNA supercoiling. In contrast, deficiency in topoisomerase I is not required for this effect.
journal_name
Antimicrob Agents Chemotherjournal_title
Antimicrobial agents and chemotherapyauthors
Aleixandre V,Herrera G,Urios A,Blanco Mdoi
10.1128/aac.35.1.20subject
Has Abstractpub_date
1991-01-01 00:00:00pages
20-3issue
1eissn
0066-4804issn
1098-6596journal_volume
35pub_type
杂志文章abstract::To investigate whether grapefruit juice inhibits the metabolism of clarithromycin, 12 healthy subjects were given water or grapefruit juice before and after a clarithromycin dose of 500 mg in a randomized crossover study. Administration of grapefruit juice increased the time to peak concentration of both clarithromyci...
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.42.4.927
更新日期:1998-04-01 00:00:00
abstract::Four isogenic derivatives with stably increased glycopeptide MICs (all become resistant to teicoplanin) were obtained from four glycopeptide-susceptible clinical isolates of Staphylococcus haemolyticus. All strains were extensively analyzed and compared for a number of distinctive features. In particular, the results ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00260-06
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abstract::Polyhexylcyanoacrylate nanoparticles loaded with either the human immunodeficiency virus (HIV) protease inhibitor saquinavir (Ro 31-8959) or the nucleoside analog zalcitabine (2',3'-dideoxycytidine) were prepared by emulsion polymerization and tested for antiviral activity in primary human monocytes/macrophages in vit...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.40.6.1467
更新日期:1996-06-01 00:00:00
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journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02143-18
更新日期:2019-03-27 00:00:00
abstract::Five isoforms of protein mannosyltransferase (Pmt) O-mannosylate secretory proteins in Candida albicans. pmt mutants were differentially defective for biofilm formation on plastic in static and flow-through systems, and a Pmt inhibitor blocked early stages of biofilm formation. Conceptually, Pmt inhibition may prevent...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00606-06
更新日期:2006-10-01 00:00:00
abstract::Sixty-three consecutive streptococcal blood isolates from neutropenic patients, represented mainly by viridans group streptococci, were evaluated in vitro for antibiotic susceptibility. Of these isolates, 79.3% were highly susceptible to penicillin (MIC, less than or equal to 0.12 microgram/ml). Overall, imipenem was ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.33.4.580
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abstract::The capacity for intracellular growth is an important survival strategy for a large group of common pathogens. Helicobacter pylori, the etiological agent for gastritis and duodenal ulcer, has been shown by both in vivo and in vitro studies to have the capacity to invade epithelial cells. In vitro models are used to st...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.40.12.2727
更新日期:1996-12-01 00:00:00
abstract::The dynamic interaction of planktonic and biofilm cells of mucoid Pseudomonas aeruginosa with tobramycin and piperacillin was investigated in a chemostat system. The results indicated that planktonic and young biofilm cells of the 2-day-old chemostat culture of P. aeruginosa were susceptible to killing by chemostat-co...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.36.6.1208
更新日期:1992-06-01 00:00:00
abstract::The organic salt triethyl-n-hexylammonium triethyl-n-hexylboride (N(2226)B(2226)) has biostatic effects against two gram-positive bacteria, Bacillus subtilis and Micrococcus luteus, and the yeast Candida albicans. Escherichia coli and chicken embryo fibroblasts grown in tissue culture are more refractory to this compo...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.8.4.510
更新日期:1975-10-01 00:00:00
abstract::The activity of cinoxacin, a synthetic organic acid antimicrobial agent, was studied and found to have in vitro activity similar to that previously reported for nalidixic acid. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.7.3.370
更新日期:1975-03-01 00:00:00
abstract::Candida biofilm infections pose an increasing threat in the health care setting due to the drug resistance associated with this lifestyle. Several mechanisms underlie the resistance phenomenon. In Candida albicans, one mechanism involves drug impedance by the biofilm matrix linked to β-1,3 glucan. Here, we show this i...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02378-12
更新日期:2013-04-01 00:00:00
abstract::The in vitro susceptibility of Brucella melitensis was examined vis-a-vis the clinical outcome in 75 patients with brucellosis. The initial MICs for Brucella isolates from patients who relapsed and from those who did not were similar. Furthermore, the MICs for isolates from patients whose infections relapsed were no d...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.30.6.958
更新日期:1986-12-01 00:00:00
abstract::Novel penem molecules with heterocycle substitutions at the 6 position via a methylidene linkage were investigated for their activities and efficacy as beta-lactamase inhibitors. The concentrations of these molecules that resulted in 50% inhibition of enzyme activity were 0.4 to 3.1 nM for the TEM-1 enzyme, 7.8 to 72 ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.48.12.4589-4596.2004
更新日期:2004-12-01 00:00:00
abstract::The in vitro activities of eight antifungal drugs against clinical isolates of Fonsecaea pedrosoi (n = 21), Fonsecaea monophora (n = 25), and Fonsecaea nubica (n = 9) were tested. The resulting MIC(90)s for all strains (n = 55) were as follows, in increasing order: posaconazole, 0.063 microg/ml; itraconazole, 0.125 mi...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01655-09
更新日期:2010-04-01 00:00:00
abstract::This study analyzed the enzymatic basis and molecular epidemiology of amoxicillin-clavulanate-resistant Escherichia coli isolated by the microbiology laboratory of a United States tertiary care hospital. From October 1998 to December 1999, all E. coli isolates were screened for ampicillin-sulbactam resistance. Of 283 ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.48.5.1520-1525.2004
更新日期:2004-05-01 00:00:00
abstract::Dientamoeba fragilis is a commonly encountered trichomonad which has been implicated as a cause of gastrointestinal disease in humans. Despite the frequency of reports recording infections with this parasite, little research has been undertaken in terms of antimicrobial susceptibility. The aim of this study was to eva...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.05125-11
更新日期:2012-01-01 00:00:00
abstract::The racemic nucleoside analogue 2'-deoxy-3'-oxa-4'-thiocytidine (dOTC) is in clinical development for the treatment of human immunodeficiency virus (HIV) type 1 (HIV-1) infection. dOTC is structurally related to lamivudine (3TC), but the oxygen and sulfur in the furanosyl ring are transposed. Intracellular metabolism ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.43.8.1835
更新日期:1999-08-01 00:00:00
abstract::In vivo antiherpesvirus effects of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil (brovavir) were tested in two mouse model infections with herpes simplex virus type 1 (HSV-1) strains which showed different degrees of virulence in mice. Successful efficacies of oral and intraperitoneal (i.p.) treatments with brova...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.34.5.691
更新日期:1990-05-01 00:00:00
abstract::The antimicrobial activity of CS-940, a new trifluorinated quinolone drug, was tested against 761 clinical isolates. CS-940 activity against members of the family Enterobacteriaceae was most similar to that of ciprofloxacin and ofloxacin, with a large range of MICs inhibiting 90% of isolates tested (MIC90S) of 0.015 t...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.39.10.2325
更新日期:1995-10-01 00:00:00
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journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01139-07
更新日期:2008-05-01 00:00:00
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journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.6.6.697
更新日期:1974-12-01 00:00:00
abstract::We conducted a retrospective study of 2,149 clinicalSalmonellastrains to help document the historical emergence of antimicrobial resistance. There were significant increases in resistance to older drugs, including ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline, which were most common inS...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02536-15
更新日期:2016-03-25 00:00:00
abstract::Spider venoms are vast natural pharmacopoeias selected by evolution. The venom of the ant spider Lachesana tarabaevi contains a wide variety of antimicrobial peptides. We tested six of them (latarcins 1, 2a, 3a, 4b, 5, and cytoinsectotoxin 1a) for their ability to suppress Chlamydia trachomatis infection. HEK293 cells...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
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更新日期:2011-11-01 00:00:00
abstract::Burkholderia pseudomallei, the causative agent of melioidosis, is inherently resistant to a variety of antibiotics including aminoglycosides, macrolides, polymyxins, and beta-lactam antibiotics. Despite resistance to many beta-lactams, ceftazidime and beta-lactamase inhibitor-beta-lactam combinations are commonly used...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.47.7.2082-2087.2003
更新日期:2003-07-01 00:00:00
abstract::Clostridioides difficile causes severe antibiotic-associated diarrhea and colitis. C. difficile is an anaerobic, Gram-positive sporeformer that is highly resistant to β-lactams, the most commonly prescribed antibiotics. The resistance of C. difficile to β-lactam antibiotics allows the pathogen to replicate and cause d...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01496-19
更新日期:2019-12-20 00:00:00
abstract::The elimination kinetics of cefotetan (YM09330), a new parenteral semisynthetic cephamycin derivative, were studied in eight healthy volunteers and 41 patients with renal insufficiency after the administration of a single 500-mg dose intravenously. Concentrations of cefotetan in serum and urine were determined by both...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
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journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01662-09
更新日期:2010-05-01 00:00:00
abstract::The effect of liposomal encapsulation of ampicillin on the antibacterial activity against intracellular Listeria monocytogenes was studied by comparing survival of L. monocytogenes within peritoneal mouse macrophages in the presence of free ampicillin alone or in combination with liposome-entrapped ampicillin. In the ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.30.2.295
更新日期:1986-08-01 00:00:00
abstract::DNA microarrays were used to analyze Candida glabrata oropharyngeal isolates from seven hematopoietic stem cell transplant recipients whose isolates developed azole resistance while the recipients received fluconazole prophylaxis. Transcriptional profiling of the paired isolates revealed 19 genes upregulated in the ma...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00535-10
更新日期:2010-08-01 00:00:00
abstract::The time course of plasma drug levels and urinary recovery for two lipopeptide antifungal antibiotics, L-671,329 and cilofungin, were measured in male rhesus monkeys (Macaca mulatta) and in female DBA/2 mice. The antibiotics were administered intravenously at 10 mg/kg of body weight in phosphate-buffered saline-26% po...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.36.3.607
更新日期:1992-03-01 00:00:00