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)

304 strains of R-plasmid harbouring enterobacteria resistant to aminoglycosides were studied for their susceptibilities to a range of antibiotics, including cefotetan. Cefotetan and latamoxef were the most active of the four cephamycins tested and all were stable to the beta-lactamases produced by these strains. No new beta-lactamases (SHV-2, CTX-1, TEM-4, CAZ-1) were found in these strains capable of hydrolysing third generation cephalosporins. The activity of cefotetan against these multi-resistant, beta-lactamase producing strains may be of clinical value.
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PMID:Comparative activity of cefotetan against plasmid-encoded aminoglycoside-resistant enterobacteria strains. 318 Mar 7

The in vitro activity of cefotetan was assessed against beta-lactamase producing clinical isolates. The majority of Enterobacteriaceae were inhibited by less than or equal to 8 micrograms/ml with 50% of isolates inhibited by less than or equal to 1 microgram/ml. Cefotetan inhibited organisms resistant to cefazolin, cefonicid and cefoperazone, but not isolates of Enterobacter, Citrobacter or Serratia resistant to ceftizoxime. Cefotetan inhibited beta-lactamase producing Haemophilus influenzae and Neisseria gonorrhoeae at less than or equal to 1 microgram/ml, but it did not inhibit Acinetobacter or Pseudomonas aeruginosa. Cefotetan was as active as cefoxitin against anaerobic species such as Bacteroides fragilis and Clostridium. Cefotetan was not hydrolyzed by Richmond-Sykes plasmid beta-lactamases of type III such as TEM and SHV, nor by the OXA or PSE beta-lactamases. It also was not hydrolyzed by cephalosporinases of Richmond-Sykes type Ia or Id. Cefotetan inhibited beta-lactamases of the type Ia and Id, but it also induced these beta-lactamases in P. aeruginosa, E. cloacae and C. freundii.
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PMID:The activity and beta-lactamase stability of cefotetan compared to other beta-lactam antibiotics. 387 87

The antibacterial activity of cefotetan, a new cephamycin, was compared with that of cephalothin, cefoxitin, cefamandole, cefoperazone and cefotaxime on 12 substrains of Escherichia coli K12 BM13 harbouring single and multi-copy plasmids coding for plasmid-mediated beta-lactamases TEM, SHVI, OXA-I and OXA-III. The 99% inhibitory concentrations (IC99) for the recipient strain were increased in proportion to the enzyme activity in the case of cefamandole and cefoperazone. In contrast, the activity of cefoxitin, cefotaxime and cefotetan was not significantly modified. Since these enzymes are responsible for the resistance of Enterobacteriaceae in the great majority of clinical isolates, cefotetan can be expected to be fully active against strains producing them. Cefotetan was not hydrolysed by chromosomal cephalosporinase and it was active against Enterobacter, Citrobacter and Morganella strains producing a low level of enzyme but hyperproducing variants were highly resistant to cefotetan.
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PMID:Comparative activity of cefotetan on Escherichia coli K12 possessing plasmid-mediated beta-lactamases. 634 49

Among clinical isolates of Escherichia coli, Klebsiella pneumoniae, and Klebsiella oxytoca, there is an ever-increasing prevalence of beta-lactamases that may confer resistance to newer beta-lactam antibiotics that is not detectable by conventional procedures. Therefore, 75 isolates of these species producing well-characterized beta-lactamases were studied using two MicroScan conventional microdilution panels, Gram Negative Urine MIC 7 (NU7) and Gram Negative MIC Plus 2 (N+2), to determine if results could be utilized to provide an accurate indication of beta-lactamase production in the absence of frank resistance to expanded-spectrum cephalosporins and aztreonam. The enzymes studied included Bush groups 1 (AmpC), 2b (TEM-1, TEM-2, and SHV-1), 2be (extended spectrum beta-lactamases [ESBLs] and K1), and 2br, alone and in various combinations. In tests with E. coli and K. pneumoniae and the NU7 panel, cefpodoxime MICs of >/=2 microg/ml were obtained only for isolates producing ESBLs or AmpC beta-lactamases. Cefoxitin MICs of >16 microg/ml were obtained for all strains producing AmpC beta-lactamase and only 1 of 33 strains producing ESBLs. For the N+2 panel, ceftazidime MICs of >/=4 microg/ml correctly identified 90% of ESBL producers and 100% of AmpC producers among isolates of E. coli and K. pneumoniae. Cefotetan MICs of >/= 8 microg/ml were obtained for seven of eight producers of AmpC beta-lactamase and no ESBL producers. For tests performed with either panel and isolates of K. oxytoca, MICs of ceftazidime, cefotaxime, and ceftizoxime were elevated for strains producing ESBLs, while ceftriaxone and aztreonam MICs separated low-level K1 from high-level K1 producers within this species. These results suggest that microdilution panels can be used by clinical laboratories as an indicator of certain beta-lactamases that may produce hidden but clinically significant resistance among isolates of E. coli, K. pneumoniae, and K. oxytoca. Although it may not always be possible to differentiate between strains that produce ESBLs and those that produce AmpC, this differentiation is not critical since therapeutic options for patients infected with such organisms are similarly limited.
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PMID:Can results obtained with commercially available MicroScan microdilution panels serve as an indicator of beta-lactamase production among escherichia coli and Klebsiella isolates with hidden resistance to expanded-spectrum cephalosporins and aztreonam? 970 95