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J F Acar

Publications and source records attributed to J F Acar.

At least 37 records · Page 2Linked to original sources
PubMed1995

SYN987, SYN1193, and SYN1253, new quinolones highly active against gram-positive cocci.

SYN987, 1193 and 1253 are new fluorinated quinolones with enhanced activity against Gram-positive bacteria. The MICs of SYN 987, 1193 or 1253 were studied by an agar dilution method against 88 streptococci (including penicillin resistant Streptococcus pneumoniae), 30 enterococci and 62 Staphylococcus aureus. SYN 987, 1193 and 1253 were 2 to 4 times more active than sparfloxacin and 16-64 times more active than older fluoroquinolones against all streptococci and ciprofloxacin-resistant S. aureus. This study demonstrates that SYN 987, 1193 and 1253 are extremely potent antibacterial agents which deserve further evaluation.

Anti-Infective Agents↗
PubMed1995

Synergistic effect of amoxicillin and cefotaxime against Enterococcus faecalis.

The antibacterial efficacy of the combination of amoxicillin and cefotaxime was assessed against 50 clinical strains of Enterococcus faecalis. For 48 of 50 strains, the MIC of amoxicillin that inhibited 50% of isolates tested decreased from 0.5 microgram/ml (range, 0.25 to 1 microgram/ml) to 0.06 microgram/ml (range, 0.01 to 0.25 microgram/ml) in the presence of only 4 micrograms of cefotaxime per ml. Alternatively, the MIC of cefotaxime that inhibited 50% of isolates tested decreased from 256 micrograms/ml (range, 8 to 512 micrograms/ml) to 1 micrograms/ml (range, 0.5 to 16 micrograms/ml) in the presence of only 0.06 microgram of amoxicillin per ml. For JH2-2, a reference strain of E. faecalis, the MICs of amoxicillin, cefotaxime, and amoxicillin in the presence of cefotaxime (4 micrograms/ml) were 0.5, 512, and 0.06 microgram/ml, respectively. By using a penicillin-binding protein (PBP) competition assay, it was shown that with cefotaxime, 50% saturation of PBPs 2 and 3 was obtained at very low concentrations (< 1 microgram/ml), while 50% saturation of PBPs 1, 4, and 5 was obtained with > or = 128 micrograms/ml. With amoxicillin, 50% saturation of PBPs 4 and 5 was obtained at 0.12 and 0.5 microgram/ml, respectively. Therefore, the partial saturation of PBPs 4 and 5 by amoxicillin combined with the total saturation of PBPs 2 and 3 by cefotaxime could be responsible for the observed synergy between these two compounds.

Amoxicillin↗
PubMed1995

Epidemiology of quinolone resistance: Europe and North and South America.

After nearly 10 years of fluoroquinolone usage for a wide range of bacterial infections, a striking difference has been observed in the incidence of bacterial resistance to fluoroquinolones between bacteria responsible for community- and hospital-acquired infections, respectively. Resistance is only rarely encountered among common pathogens. In most studies, 97 to 100% of all pathogens are fully susceptible to fluoroquinolones. In contrast, resistance to fluoroquinolones has emerged and increased among bacteria responsible for nosocomial infections. The incidence of resistance to fluoroquinolones varies between bacterial species, clinical settings and countries, and is related to local epidemic spread of a few clones. The highest incidence of resistance is observed in Pseudomonas aeruginosa, Acinetobacter spp., Serratia marcescens and, particularly, methicillin-resistant Staphylococcus aureus (MRSA): some investigators have reported 95 to 100% fluoroquinolone resistance among MRSA. Follow-up of trends in the resistance to fluoroquinolones based upon surveillance programmes are needed.

4-Quinolones↗
PubMed1995

[Corynebacterium diphtheriae endocarditis complicated by septic arthritis and cerebral abscess].

The authors report a rare case of the mitis type Corynebacterium diphteriae endocarditis on a prosthetic valve complicated by septic arthritis and cerebral abscess. The authors underline the importance of regular transoesophageal echocardiographic control and underline the diagnostic value of ultrafast computed tomography for the diagnosis of aortic annular and interventricular septal abscesses in patients with mechanical prosthetic valves.

Arthritis, Infectious↗
PubMed1994

Comparative activity of teicoplanin and vancomycin against 400 penicillin susceptible and resistant Streptococcus pneumoniae. The French Study Group.

The MICs of teicoplanin and vancomycin were determined for 400 penicillin-susceptible and -resistant strains of Streptococcus pneumoniae isolated during a multicenter study in 1992. Teicoplanin displayed a four-fold better activity than vancomycin, with modal MICs of these agents being 0.06 and 0.25 micrograms/ml, respectively. These data warrant further studies with teicoplanin in the treatment of pneumococcal infections.

Microbial Sensitivity Tests↗
PubMed1994

N,N-dimethylglycyl-amido derivative of minocycline and 6-demethyl-6-desoxytetracycline, two new glycylcyclines highly effective against tetracycline-resistant gram-positive cocci.

The in vitro activities of the N,N-dimethylglycyl-amino derivative of minocycline (DMG-MINO) and 6-dimethyl-6-dexoxytetracycline (DMG-DMDOT), members of a new generation of tetracyclines, were evaluated by an agar dilution method and were compared with those of tetracycline and minocycline against 224 tetracycline-resistant and 73 tetracycline-susceptible recent clinical isolates of gram-positive cocci, including multiple-antibiotic-resistant methicillin-resistant Staphylococcus aureus and penicillin-resistant Streptococcus pneumoniae. The MICs of DMG-MINO and DMG-DMDOT were up to 500- to 2,000-fold lower than those of tetracycline against methicillin-resistant S. aureus and Streptococcus pneumoniae (MIC for 50% of strains tested [MIC50], < 0.06 microgram/ml). Against Streptococcus groups A, B, C, and G and Enterococcus faecalis, the MIC50 was 0.5 microgram/ml. MIC50s were greater only for coagulase-negative staphylococci (2 micrograms/ml). These data indicate that DMG-MINO and DMG-DMDOT are very potent drugs, and further in vitro and in vivo studies are warranted.

Coagulase↗
PubMed1994

[Antibacterial activity of ciprofloxacin in the urine during four days after a single 500 mg and 750 mg oral dose].

Antibacterial activity of ciprofloxacin was studied in the urine after a single 500 mg and 750 mg oral dose in ten healthy female volunteers. Urine was collected, after each single oral dose, during seven time periods: 0-3 h, 3-6 h, 6-12 h, 12-24 h, 24-48 h, 48-72 h, 72-96 h. Ciprofloxacin concentrations were assayed by microbiological method. Urine antibacterial activity was determined for five bacterial strains isolated in urine: 2 E. coli strains, one sensitive and the other resistant to nalidixic acid (Nal-A), 1 Klebsiella pneumoniae resistant to nalidixic acid (Nal-B), 1 Staphylococcus saprophyticus and 1 Enterococcus faecalis. MICs of ciprofloxacin against these strains were respectively 0.003, 0.06, 0.25, 0.06 and 0.5 micrograms/ml. Ciprofloxacin mean concentrations in the seven urine samples were 292.5 +/- 55.8, 81.1 +/- 16.9, 43.7 +/- 11.6, 11.5 +/- 1.9, 1.3 +/- 0.2, 0.3 +/- 0.05 et 0.1 +/- 0.05 micrograms/ml after a single 500 mg oral dose and 215.1 +/- 68.1, 56.1 +/- 17.8, 43 +/- 8.8, 14.4 +/- 5.5, 1.4 +/- 0.2, 0.4 +/- 0.1 and 0.2 +/- 0.05 micrograms/ml after a single 750 mg oral dose. Urine bacteriostatic activity was not very different after a 500 mg dose and a 750 mg dose. Against enterobacteriacae, after a 500 mg dose it was > or = 16 the first day; it was > or = 512 for the Nal-S E. coli. It was > or = 64 the first day, and remained between 2 and 32 the second day for the Nal-R strains (E. coli and Klebsiella).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1993

Activity of the beta-lactamase inhibitor BRL 42715 against cephalosporinases produced by Enterobacteriaceae.

BRL 42715, a novel beta-lactamase inhibitor, was evaluated for its capacity to inhibit cephalosporinases. BRL 42715 was effective in potentiating the activity of antibiotics against clinical isolates of Enterobacteriaceae that produced high levels of cephalosporinases. This correlated well with the very low 50% inhibition values (< 0.004 mg/L) of BRL 42715 for cephalosporinases extracted from different species. When compared in vitro to clavulanic acid, sulbactam, and tazobactam, BRL 42715 was the most efficient inhibitor of cephalosporinase.

Anti-Bacterial Agents↗
PubMed1993

Susceptibility survey of piperacillin alone and in the presence of tazobactam.

Among 325 fresh isolates of bacteria from 153 hospital patients with serious infections, 142 were susceptible to piperacillin, 129 were resistant and a further 54 exhibited a marked inoculum effect. Tazobactam restored the susceptibility of resistant isolates of Staphylococcus aureus and Staphylococcus epidermidis (except methicillin-resistant isolates), Haemophilus influenzae, Moraxella catarrhalis, Acinetobacter spp. and Bacteroides fragilis. Among 87 Enterobacteriaceae that were resistant to piperacillin, or showed an inoculum effect, 78 (89%) were restored to susceptibility by tazobactam. Pseudomonas spp. resistant to piperacillin were mostly resistant to the combination.

Bacteria↗
PubMed1993

In-vitro antibacterial activity of cefepime: a multicentre study.

The antimicrobial activity of cefepime, a new broad-spectrum parenteral cephalosporin, was evaluated in vitro against 1757 recent clinical Gram-positive and Gram-negative isolates. Cefepime was active at low concentrations (MIC50 values < or = 0.06 mg/L and MIC90 values < or = 0.12 mg/L) against non-cephalosporinase-producing Enterobacteriaceae (Escherichia coli, Proteus mirabilis, Salmonella spp. and Shigella spp.). For Klebsiella pneumoniae, MICs were between 0.016 and 16 mg/L; the highest MIC values were observed for extended-spectrum beta-lactamase-producing strains. Against Enterobacteriaceae, such as cephalosporinase producing Enterobacter cloacae, MICs were < or = 0.5 mg/L, but MICs against cephalosporinase hyperproducing strains were generally higher. Ticarcillin-sensitive strains of Pseudomonas aeruginosa were inhibited by cefepime concentrations of 0.5-16 mg/L, while cefepime MICs were 8-64 mg/L for strains resistant to ticarcillin. The cefepime MIC50 value for Haemophilus spp. including many resistant to amoxycillin, was 0.03 mg/L. Against methicillin-sensitive strains of Staphylococcus aureus, cefepime MICs were 0.5-16 mg/L; MICs against methicillin-resistant staphylococci were 16- > 128 mg/L). Against methicillin-sensitive coagulase-negative staphylococci, cefepime MIC values were 0.03-16 mg/L; corresponding values for methicillin-resistant strains were 2-128 mg/L. Streptococci (Groups A, C and G) were sensitive to cefepime with MICs ranging from < or = 0.008-2 mg/L (MIC50, 0.03 mg/L; MIC90, 0.25 mg/L). The activity of cefepime against Group B streptococci and pneumococci were comparable, with MIC50 values of 0.12 and 0.25 mg/L, respectively, and MIC90 values of 0.03 and 0.25 mg/L, respectively. Most enterococci and all Listeria monocytogenes strains had MICs > or = 32 mg/L.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗
PubMed1993

The epidemiology of bacterial resistance to quinolones.

The new fluoroquinolones have been in use for nearly 10 years in the treatment of community- and nosocomially-acquired infections. Resistant clones may be selected during therapy and disseminate if favourable epidemiological conditions prevail. Resistance to the fluoroquinolones is still rare in common pathogens with 97 to 100% of strains remaining susceptible. Resistance has been reported in methicillin-susceptible Staphylococcus aureus, Campylobacter jejuni/coli, Salmonella, Shigella and Escherichia coli. Among nosocomial pathogens, the incidence of fluoroquinolone resistance varies between bacterial species, countries and periods of study, and is dependent on local epidemiological factors and antibiotic policies. The highest incidence of resistance is observed in Serratia and Acinetobacter spp., and particularly in methicillin-resistant S. aureus. Surveillance programmes are needed to follow up trends in resistance to the fluoroquinolones and their possible association with clinical failures.

Anti-Infective Agents↗
PubMed1993

Epidemiology of resistance to diaminopyrimidines.

Resistance to trimethoprim emerged in Enterobacteriaceae and later in other Gram-negative and Gram-positive bacteria within two years of the clinical introduction of the drug. Resistance is borne in many different replicons often present in multiply-resistant epidemic bacteria. The incidence of trimethoprim resistance is highly variable, depending upon methodology, type of patients, local epidemiology: this can be illustrated by the high variation of trimethoprim resistance among Salmonella, Shigella or MRSA in various countries and by the incidence of resistance in penicillin-resistant Streptococcus pneumoniae.

Cross Infection↗
PubMed1992

Antimicrobial resistance in Streptococcus pneumoniae: an epidemiological survey in France, 1970-1990.

The antimicrobial resistance of Streptococcus pneumoniae was surveyed in 1970-1990 at Saint Joseph and Broussais hospitals in Paris (3,279 isolates) and in 1984-1990 at the National Reference Center for Pneumococci (NRCP) in Créteil (8,128 isolates). All isolates were tested for susceptibility and serotyped. At St. Joseph and Broussais hospitals, the rate of resistance to tetracycline increased from 14% in 1970 to 46.5% in 1978 and then decreased to approximately 20% in 1988-1990. Resistance to chloramphenicol appeared in 1972; its frequency remained at less than 10% until 1990. Resistance to macrolides was first detected in 1976, increased to 20% in 1984, and reached 29% in 1990. Among strains submitted to the NRCP, resistance to penicillin (MIC, greater than or equal to 0.1 mg/L) remained infrequent (less than or equal to 1.1%) between 1984 and 1986 but then increased steadily, reaching 12% in 1990. The frequency of high-level resistance to penicillin (MIC, greater than 1 mg/L) among penicillin-resistant pneumococci increased from 13% in 1988 to 48% in 1990. Compared with other serotypes, the penicillin-resistant serotype isolated most frequently (23F, 49.3%) was more often highly resistant to penicillin and was more often multiresistant.

Drug Resistance, Microbial↗