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J L Muñoz Bellido

Publications and source records attributed to J L Muñoz Bellido.

At least 19 recordsLinked to original sources
PubMed2006

Molecular epidemiology of drug-resistant Salmonella Typhimurium in Spain.

One hundred and forty-seven Salmonella serotype Typhimurium strains isolated in three provinces in the midwest of Spain were studied. Of these, 93.6% were drug resistant. There were two predominant resistance phenotypes: 43 isolates (29.3%) were resistant to amoxicillin, tetracyclines, chloramphenicol, streptomycin and sulphamethoxazole and 27 isolates (18.4%) to amoxicillin, amoxicillin/clavulanic acid, tetracyclines, chloramphenicol, streptomycin and sulphamethoxazole. Randomly amplified polymorphic DNA (RAPD) analysis and pulsed field gel electrophoresis (PFGE) were performed for molecular typing. Thirty-six DNA band profiles were differentiated by RAPD, and 38 by PFGE. We found a high level of clonality; 27% of strains were identical by both methods. There were additional smaller clonal lines within every area. The highest discriminatory power was obtained with PFGE, but the greatest degree of genetic diversity was observed among Salmonella Typhimurium using both RAPD and PFGE.

Drug Resistance, Bacterial↗
PubMed2005

[Prevalence of anti-Chlamydophila pneumoniae antibodies in patients with intrinsic asthma].

Chlamydophila pneumoniae is a respiratory pathogen which has been involved in the pathogenesis of a number of chronic diseases. We studied the association between IgG antibodies against C. pneumoniae and intrinsic asthma in adults. C. pneumoniae IgG serum titers were determined by enzymatic immunoassay in 55 adult patients and 87 healthy controls. A significant association was found between anti-C. pneumoniae antibodies and intrinsic asthma, as compared to the control group (23.6% vs. 10.3%, p <0.05). C. pneumoniae may therefore be involved in the origin or in exacerbations of intrinsic asthma.

Adult↗
PubMed2003

In vitro activity of newer antibiotics against Corynebacterium jeikeium, Corynebacterium amycolatum and Corynebacterium urealyticum.

The in vitro activity of ciprofloxacin, erythromycin, telithromycin, teicoplanin, linezolid and quinupristin-dalfopristin was tested against human derived pathogenic corynebacteria. The MICs of these antibiotics were measured using the agar dilution method against 31 strains of Corynebacterium jeikeium, 58 Corynebacterium amycolatum (including 33 multidrug-resistant strains) and 64 Corynebacterium urealyticum clinical strains. A high resistance rate to ciprofloxacin and erythromycin was found in the three species. Telithromycin was much more active than erythromycin (MIC(90) of erythromycin >or=128 mg/l for all three species; MIC(90) of telithromycin: 4 mg/l for C. jeikeium, 64 mg/l for C. amycolatum and 1 mg/l for C. urealyticum). There were no teicoplanin-resistant (MIC(90) 1, 0.5 and 1 mg/l, respectively) or linezolid-resistant strains (MIC(90) 1, 0.2 and 0.5 mg/l, respectively). Quinupristin-dalfopristin was active against most strains with an activity similar to linezolid, but three C. jeikeium and one C. amycolatum showed MICs >or=4 mg/l. Telithromycin showed much better activity against corynebacteria than older macrolides. Synercid and linezolid were active against most isolates tested, including multidrug resistant strains.

Acetamides↗
PubMed2002

In vitro activity of linezolid, synercid and telithromycin against genetically defined high level fluoroquinolone-resistant methicillin-resistant Staphylococcus aureus.

The in vitro activity of levofloxacin, moxifloxacin, gatifloxacin, erythromycin, telithromycin, linezolid, synercid and vancomycin was measured against 36 genetically defined, gyrA/grlA double mutant MRSA clinical strains with an MIC to ciprofloxacin > or = 8 mg/l. The three newer fluoroquinolones tested were more active than ciprofloxacin. Resistance rates for levofloxacin and gatifloxacin were high (44.5 and 36.1%, respectively). All the strains were moxifloxacin-susceptible, though most of them had MICs close to the break point. All the strains were intermediate or resistant to erythromycin and most were also resistant to telithromycin. No strains were resistant to linezolid, synercid or vancomycin (MIC(90): 2, 1 and 2 mg/l, respectively).

Acetamides↗
PubMed2002

[In vitro activity of moxifloxacin against respiratory pathogens in Latin America].

We compared the in vitro activity of moxifloxacin, levofloxacin and six other antibiotics frequently used in respiratory tract infections, against 1563 Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, Haemophilus influenzae and Moraxella catarrhalis clinical isolates from 21 centers in 10 Latin American countries from March 2000 to April 2001. Moxifloxacin was the most active compound against all the species included. Moxifloxacin was 2- to 4-fold more active than levofloxacin against Gram-positive bacteria. This difference was much higher against levofloxacin-resistant S. pneumoniae isolates (MIC: 0.5 mg/l vs 8 mg/l). The activity of moxifloxacin against H. influenzae and M. catarrhalis was similar to levofloxacin; all the isolates were inhibited at < or = 1 mg/l concentrations of moxifloxacin and levofloxacin.

Anti-Infective Agents↗
PubMed2001

Molecular diversity of quinolone resistance in genetically related clinical isolates of Staphylococcus aureus and susceptibility to newer quinolones.

The genes encoding topoisomerases (gyrA and grlA) and the norA promoter of 100 fluoroquinolone-susceptible and -resistant Staphylococcus aureus clinical isolates obtained in two geographically distant hospitals were analysed. The relationship between mutations found and the susceptibility to newer quinolones was determined. Thirty-nine strains were grouped in seven clones by pulsed-field gel electrophoresis (PFGE). The remaining 61 strains were classified as unrelated strains. In three clones, all strains showed the same grlA-gyrA-norA mutation profiles. Strains in the rest of the groups showed different mutation profiles, even though PFGE indicated that they possessed genetically similar populations. One cluster showed a high level of diversity; five different mutation profiles were detected in the six isolates belonging to this pattern. Two isolates had a Glu84 to Lys mutation in grlA and another isolate had this mutation combined with a Ser84 to Leu mutation in gyrA. Combination of a Ser80 to Phe mutation in grlA and a Ser84 to Leu in gyrA was found in the two other isolates. One of these also had a thymine to a guanine transversion at a position 89 nucleotides upstream of the norA start codon in the norA promoter. These results show that fluoroquinolone resistance in clinical S. aureus strains does not necessarily result from the spread of resistant clones. Fluoroquinolone resistance may develop independently in strains belonging to the same PFGE pattern by accumulation of different mutations over a quinolone-susceptible ancestor wild type or single grlA mutant.

4-Quinolones↗
PubMed2000

The role of fluoroquinolones in respiratory tract infections: community acquired pneumonia.

Newer fluoroquinolones may play an important role in the management of community acquired pneumonia. They retain activity similar to older fluoroquinolones against Gram-negative bacteria and are significantly more active against Gram-positive bacteria, especially pneumococci. They are also active against bacteria causing atypical pneumonia, penicillin-sensitive and -resistant and macrolide-sensitive and -resistant pneumococci and against beta-lactamase producing and non-producing Haemophilus influenzae. They have similar or slightly lower activity than ciprofloxacin against other Gram-negative organisms. They have rapid bactericidal activity and attain good lung tissue levels. Clinical studies show results similar or better than older treatments. Their impact on ecology and resistance remains to be elucidated but data on side effects and toxicity must be carefully evaluated.

Anti-Infective Agents↗
PubMed2000

[Activity of new quinolones against clinical isolates of Corynebacterium species].

The activity of six quinolones (ciprofloxacin, levofloxacin, trovafloxacin, moxifloxacin, clinafloxacin and grepafloxacin) against 86 clinical isolates of Corynebacterium spp. obtained from different clinical sources was studied. Of these, 30 isolates were identified as C. jeikeium, 30 as C. urealyticum and 26 as C. amycolatum. C. amycolatum was the most resistant species, with 85.5% of the strains analyzed resistant to all the quinolones studied. Clinafloxacin showed the best activity against these species with a concentration range between <0.01 and 8 mg/l, and MIC50 and MIC90 64 and 32 times lower, respectively, than the MICs of ciprofloxacin. The majority of the isolates (90%) of C. jeikeium and C. urealyticum were susceptible to all the quinolones studied. Only 9.9% of the C. jeikeium strains and 13.2% of the C. urealyticum strains were resistant to ciprofloxacin, which showed the lowest activity of the antimicrobial agents evaluated. Clinafloxacin, grepafloxacin and moxifloxacin were the most active quinolones against these two multiresistant species.

Anti-Infective Agents↗
PubMed2000

[In vitro activity of new quinolones against clinical strains of Staphylococcus aureus of the wild type and with mutations characterized by gyrA, gyrB and grlA].

The aim of this study was to determine the in vitro activity of five quinolones against clinical strains of methicillin-susceptible and -resistant Staphylococcus aureus clinical isolates characterized at the molecular level with respect to the presence of mutations in genes coding for resistance to quinolones (grlA, gyrA and gyrB). The relationship between the mutations found and the activities of these quinolones was also analyzed. Trovafloxacin was the most active against methicillin-susceptible S. aureus and showed good activity against methicillin-resistant S. aureus, with a MIC90 of 2 mg/l. The grlA-gyrA double mutation was the most frequent (55% of the strains). Single mutation in grlA was detected only in 5% of strains; 39% of strains showed a wild-type genotype. The grlA-gyrA double mutants presented a high level of resistance against the fluoroquinolones tested except for trovafloxacin, with the MIC ranging between 0.5 and 4 mg/l. Wild-type strains were susceptible to all the fluoroquinolones tested and the single grlA mutants had a low level of quinolone resistance but were still below the breakpoint for resistance. Trovafloxacin and sparfloxacin were less affected by this mutation.

Anti-Infective Agents↗
PubMed1999

In vitro activities of 13 fluoroquinolones against Staphylococcus aureus isolates with characterized mutations in gyrA, gyrB, grlA, and norA and against wild-type isolates.

The in vitro activities of 13 fluoroquinolones (FQs) were tested against 90 Staphylococcus aureus clinical isolates: 30 wild type for gyrA, gyrB, grlA and norA and 60 with mutations in these genes. Clinafloxacin (CI-960), sparfloxacin, and grepafloxacin were the most active FQs against wild-type isolates (MICs at which 90% of isolates were inhibited, 0.06 to 0.1 microgram/ml). Mutations in grlA did not affect the MICs of newer FQs. grlA-gyrA double mutations led to higher MICs for all the FQs tested. Efflux mechanisms affected the newer FQs to a much lesser extent than the less recently developed FQs.

Anti-Infective Agents↗
PubMed1999

In vitro activity of eight fluoroquinolones against multiresistant Stenotrophomonas maltophilia.

We studied the activity of eight fluoroquinolones (norfloxacin, ciprofloxacin, grepafloxacin, trovafloxacin, gatifloxacin, clinafloxacin, PD-117596 and PD-138312) against 58 multiresistant Stenotrophomonas maltophilia clinical strains. Norfloxacin was the least active drug (MIC(90) = 128 mg/l). Grepafloxacin, trovafloxacin and gatifloxacin activity was moderately higher (MIC(90) = 8 mg/l) than ciprofloxacin (MIC(90) = 16 mg/l). The best activity was shown by clinafloxacin and PD-138312 (MIC(90) = 4 mg/l). The most resistant strains showed similar MICs against all the fluoroquinolones tested. The highest increase of activity of newer fluoroquinolones was observed against the most sensitive strains.

Anti-Infective Agents↗