Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0276640 (TEM)
 20,729 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three concentrations of the penicillanic acid sulfone, sulbactam were tested in combination with cefoperazone against 632 recent clinical bacterial isolates. Cefoperazone was effective alone (less than or equal to 16 micrograms/mL) against 95% of Enterobacteriaceae and combined with 4 micrograms/mL sulbactam inhibited 99.5% of strains. This coverage of enteric bacilli was superior to timentin (99.1%), ceftazidime (98.2%), and tobramycin (90.9%). The minimum inhibitory concentrations (MICs) of cefoperazone-susceptible strains also were markedly decreased by sulbactam (overall MIC90s, 8.0 micrograms/mL for cefoperazone and 1.0 microgram/mL for cefoperazone and 4.0 micrograms/mL for sulbactam). Sulbactam also expanded the spectrum of cefoperazone against Acinetobacter species, some rare Pseudomonas species, and Bacteroides fragilis group species. Sulbactam had direct antimicrobial activity against the acinetobacters and Pseudomonas acidovorans, but the increased activity of cefoperazone-sulbactam against some other Pseudomonas species and anaerobes was attributed to beta-lactamase inhibition. The cefoperazone MICs against beta-lactamase producing Staphylococcus species also were lowered to the level of enzyme-deficient strains. Cefoperazone bactericidal activity was improved by 4.0 micrograms/mL sulbactam, and no antagonism was observed. beta-lactamase hydrolysis studies confirmed a slow hydrolysis of cefoperazone only by TEM beta-lactamases and a high-grade resistance to enzyme breakdown by sulbactam. Differential beta-lactamase affinity studies for cefoperazone and sulbactam showed potential efficacy and applications to plasmid-mediated TEM and OXA enzymes and only marginal effective sulbactam inhibition of Pseudomonas and Klebsiella species enzymes. Disk diffusion studies on 556 strains confirmed the applicability of the cefoperazone 75-micrograms disk to testing routine isolates other than enterococci and methicillin-resistant Staphylococcus aureus. The addition of 4.0 micrograms sulbactam/mL in a fixed concentration to dilution test systems and 15 micrograms sulbactam to the 75 micrograms cefoperazone disk were recommended for in vitro tests. Susceptibility and resistant interpretive criteria for the disk and dilution tests can be applied with confidence. Only 0.4% false-susceptibility errors and a 97.5% absolute interpretive agreement were achieved using the 75 micrograms cefoperazone/15 micrograms sulbactam disk.
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PMID:The cefoperazone-sulbactam combination. In vitro qualities including beta-lactamase stability, antimicrobial activity, and interpretive criteria for disk diffusion tests. 299 61

Cefoperazone was tested against 554 clinical isolates alone and with sulbactam in three combinations. The addition of sulbactam in low concentrations (less than or equal to 4 micrograms/ml) improved the spectrum of cefoperazone principally against gram-negative bacilli such as Acinetobacter species, some Pseudomonas species, and beta-lactamase-positive Enterobacteriaceae. Nearly all of the spectrum increase was achieved at a sulbactam level of less than or equal to 2 micrograms/ml. Sulbactam was found to be an effective antimicrobial agent against Acinetobacter species (MIC50, 1.0 microgram/ml), Pseudomonas acidovorans (MIC50, 2.0 micrograms/ml), Neisseria gonorrhoeae (MIC50, less than or equal to 0.5 microgram/ml), and N. meningitidis (MIC50, less than or equal to 0.5 microgram/ml). Sulbactam had a higher affinity and binding constant for the plasmid-mediated beta-lactamases such as TEM-1 and TEM-2 compared to cefoperazone (greater than or equal to 10-fold difference). This finding was important as cefoperazone can be hydrolyzed at a moderate rate by the highly efficient TEM enzymes (less than 2% of clinical Escherichia coli isolates). Sulbactam increased the susceptibility (less than or equal to 16 micrograms/ml) of 220 isolates of Enterobacteriaceae to cefoperazone from 88.6 to 96.3% when 4.0 micrograms/ml of sulbactam was added. The cefoperazone antimicrobial activity was also increased against the nonenteric bacilli from a 69.5 to a 87.4% total inhibition. MICs among cefoperazone-susceptible gram-negative and gram-positive strains were routinely decreased 2- to 32-fold, as calculated from MIC90 results. Therefore, sulbactam should predictably increase the antimicrobial spectrum and clinical effectiveness of cefoperazone against nosocomial and other pathogens such as the plasmid-containing enteric bacilli, Bacteroides species and Acinetobacter species, and possibly provide the opportunity to reduce dosage schedules for infecting species already susceptible to cefoperazone alone.
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PMID:In vitro antimicrobial activity of cefoperazone-sulbactam combinations against 554 clinical isolates including a review and beta-lactamase studies. 299 94

Comparison of the activity of cefoperazone, cefamandole, cefotaxime, cephalothin and moxalactam against Enterobacteriaceae showed cefoperazone to be twofold (Escherichia coli, Klebsiella) to eigthfold (Enterobacter) more active than cefamandole. The lowes MIC values were found for cefotaxime (0.03 - 0.25 microgram/ml) followed by moxalactam (0.06 - 0.25 microgram/ml). Cefoperazone stood out in activity against Pseudomonas aeruginosa (MIC50 4 microgram/ml). Cephalothin resistance affected the MIC values of cefoperazone and moxalactam only to a small degree. From beta-lactamase susceptibility studies it was concluded that cefoperazone may be hydrolyzed by TEM type beta-lactamases, but that the cephalosporinases (class I) and the chromosomal broad-spectrum beta-lactamases (class IV) only have little effect on this antibiotic. Moxalactam was not degraded by any of the beta-lactamase preparations tested.
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PMID:Activity and specific beta-lactamase susceptibility of cefoperazone and moxalactam. Comparison with other cephalosporins. 645 58

High therapeutic efficacies of ceftriaxone, ceftazidime, cefotaxime and azthreonam in the treatment of experimental plague induced by beta-lactamase-producing strains of the plague microbe containing R plasmids RP-1, R57b and R40a were shown to correlate with their in vitro antibacterial activities. The therapeutic efficacy of sulbactam/ampicillin was recorded in the treatment of plague induced by the strain containing R plasmids R57b and R40a (the treatment course of 7 days). However, it was lower when the infection was due to the strain containing plasmid RP-1 (beta-lactamase TEM-2). Cefoperazone was not active in the treatment of experimental plague induced by the strains containing plasmids RP-1 and R57b (beta-lactamases TEM-2 and OXA-3). Ceftriaxone versus the antibiotics tested was considered to be the drug of choice for the etiotropic therapy of plague induced not only by the type strains of the plague microbe but also by its variants with the plasmid pattern resistance to penicillins.
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PMID:[Experimental evaluation of prospects for the use of beta-lactams in plague infection caused by pathogens with plasmid resistance to penicillins]. 1007 60