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

The antimicrobial activity of ceftibuten, a new oral cephalosporin, was evaluated using 4735 clinical bacterial isolates processed at four medical centers. Ceftibuten inhibited nearly 92% of all Enterobacteriaceae (less than or equal to 8.0 micrograms/ml), thereby being markedly superior to cefixime which inhibited 78.7% at less than or equal to 1.0 microgram/ml and cefuroxime which inhibited 45.1% at less than or equal to 2.0 micrograms/ml. Pseudomonads and staphylococci were not within the spectrum of activity of ceftibuten. Ceftibuten was found to be very stable in the presence of five commonly occurring beta-lactamases of both the chromosomal-mediated (P99, K1) and plasmid-mediated (CARB-2, OXA-1, TEM-1) types. Only Type Ia (P99) beta-lactamase was significantly inhibited by ceftibuten. On the basis of results of a ceftibuten MIC quality control study conducted in five laboratories, a quality control range of 0.12 to 0.5 microgram/ml is recommended for the Escherichia coli ATCC 25922 strain.
 ...
PMID:Ceftibuten (7432-S, SCH 39720): comparative antimicrobial activity against 4735 clinical isolates, beta-lactamase stability and broth microdilution quality control guidelines. 314 69

The in vitro activity of E-1040 [(6R,7R)-3-[(4-carbamoyl-1-quinuclidinio)methyl]-7-[2-(5-amino-1,2 ,4- thiadiazol-3-yl)-(Z)-2-methoxyiminoacetoamido]-8-oxo-5-thia- 1- azabicyclo(4,2,0)oct-2-ene-2-carboxylate], a novel cephalosporin, was compared with that of ceftazidime, cefpirome, cefepime, imipenem, and gentamicin. E-1040 inhibited 50% of members of the family Enterobacteriaceae, Pseudomonas aeruginosa, and Haemophilus and Neisseria species at less than or equal to 0.25 microgram/ml, and the MIC for 90% of strains tested ranged from 0.06 to 2 micrograms/ml. It was two- to fourfold more active than ceftazidime and similar in activity to cefepime and cefpirome. It inhibited Enterobacter, Citrobacter, Serratia, and Morganella species that were resistant to ceftazidime. E-1040 inhibited imipenem-, piperacillin-, aztreonam-, and tobramycin-resistant P. aeruginosa. It was less active against Xanthomonas maltophilia and P. cepacia but inhibited other Pseudomonas species. The activity of E-1040 against staphylococci and hemolytic streptococci was similar to that of ceftazidime, but E-1040 was less active than cefepime and cefpirome. It did not inhibit Bacteroides spp. There was no inoculum effect or medium effect, and MBCs were within a dilution of MICs. Plasmid beta-lactamases TEM-1, TEM-2, TEM-3 (CTX-1), SHV-1, Staphylococcus aureus, PSE, and CARB did not hydrolyze E-1040. Chromosomal beta-lactamases P99 and K-1 did not hydrolyze E-1040; E-1040 had poor affinity for these enzymes, with a Ki of greater than 100 microM.
 ...
PMID:In vitro activity of E-1040, a novel cephalosporin with potent activity against Pseudomonas aeruginosa. 315 Sep 15

beta-Lactamase identification by colony hybridization with 32P-labeled DNA probes for TEM-1, SHV-1, OXA-1, OXA-2, PSE-1, PSE-2, and PSE-4 was compared with isoelectric focusing in 122 clinical isolates making a variety of enzyme types. All strains producing a probe-type enzyme gave a positive hybridization reaction. Cross-hybridization was observed between TEM-1 and TEM-2 or TLE-1, between SHV-1 and SHV-2, between OXA-1 and OXA-4, between OXA-2 and OXA-3 (weak), between PSE-2 and OXA-6 or OXA-5 (weak), and among PSE-1, PSE-4, and CARB-3. With allowance for such cross-hybridization, only six strains gave false-positive reactions, and the procedure was 99% specific.
 ...
PMID:Detection of plasmid-mediated beta-lactamases with DNA probes. 325 20

One hundred clinical strains of Acinetobacter calcoaceticus isolated from 1981 to 1986 were screened for enzymatic resistance to beta-lactam antibiotics. Fourteen beta-lactam antibiotics were tested and four phenotypes were defined on the basis of enzymatic resistance and of susceptibility to the following beta-lactams: ticarcillin, piperacillin, cefotaxime, and ceftazidime. The resistance of A. calcoaceticus to beta-lactam antibiotics was predominantly due to beta-lactamases, which were produced by 81% of the strains. In most (71%) of the beta-lactamase producing strains, a penicillinase of the TEM type was observed; in 9% of the strains, all isolated since 1985, a CARB-type penicillinase with a pI 6.3 was observed. The presence of a cephalosporinase type enzyme was detected in acinetobacter strains isolated since 1981 and its incidence increased in 1986. Multiple beta-lactamases (penicillinase plus cephalosporinase) were observed in 32% of the strains.
 ...
PMID:Distribution of beta-lactamases and phenotype analysis in clinical strains of Acinetobacter calcoaceticus. 326 30

The ongoing discoveries of new beta-lactamases, mainly penicillinases, in Gram-negative bacteria has emphasized the problem of their precise identification, and thus their phylogeny. Crude extracts, prepared by sonication, of 14 plasmid beta-lactamases, types TEM, carbenicillinases (CARB or PSE) and oxacillinases (OXA) were analysed by a simple, rapid (3.5 to 4 hours) method of electrophoresis on polyacrylamide (7%) agarose (1.4%) gels, using Tris-glycine buffer at pH 8.7. Preliminary serial dilutions were made to determine enzymic activity levels. Enzymes were then characterized by their relative electrophoretic mobilities. These mobilities had coefficients of variability between 2% and 10%, ranged from 5 to 61, and were correlated with their isoelectric points (pI). Thus, the lower the pI is, the greater the mobility is. Despite the high resolving power of the polyacrylamide-agarose gel system, enzymes with similar pI's and of similar types (PSE-1 and CARB-3, or OXA-1 and OXA-4) or different types (SHV-1 and OXA-6) could not be distinguished on the basis of their mobilities. However, this technique provides for rapid and easy identification of the major penicillinases in Gram-negative bacteria. A combination of polyacrylamide-agarose gel electrophoresis and pH gradient electrophoresis (titration curve) could provide a powerful approach to the study of the molecular structure of these enzymes.
 ...
PMID:[Electrophoretic behavior of beta-lactamases in gram-negative bacteria]. 328 89

Susceptibility testing of 7,775 recent clinical isolates from four medical centers showed Ro 15-8074 to be 2-to greater than 8-fold more active than either cefaclor or cefuroxime against the Enterobacteriaceae. Ro 15-8074 MICs for 50% of the strains tested were greater than or equal to 32 micrograms/ml for Staphylococcus spp., enterococci, Pseudomonas aeruginosa, and Pseudomonas maltophilia. beta-Lactamase hydrolysis experiments failed to demonstrate significant Ro 15-8074 inactivation by commonly encountered chromosomal or plasmid-mediated enzymes (P99, K1, K14, TEM, and CARB).
 ...
PMID:Antimicrobial activity of Ro 15-8074, active metabolite of a new oral cephalosporin (Ro 15-8075), against 7,775 recent clinical isolates. 349 61

Although still there are Klebsiella strains which do not harbour plasmids and produce constitutive chromosomal beta-lactamases, recently clinical isolates were found in ever increasing numbers carrying mainly TEM-, CARB- and OXA type R-factors. We selected four chromosomal cephalosporinase producing Klebsiella strains to study the pI values of the enzymes and their simultaneous separability from accompanying proteins by chromatofocusing techniques. We compared pI values of the pure and the crude preparations: K. pneumoniae K1 SC 10436: pIpure = 6.4, pIcrude = 6.42; K. aerogenes K1 1082 E: pIpure = 6.5, pIcrude = 6.5; K. oxytoca 1082 E: pIpure = 6.42, pIcrude = 6.4; K. oxytoca 20: pIpure = 7.62, pIcrude = 7.6. Excellent agreement of the pI values among each other, but occasional differences with those obtained by analytical isoelectrofocusing are attributed to methodological diversities and to the presence of satellite enzymes, known to exist in Klebsiella.
 ...
PMID:Use of chromatofocusing for separation of beta-lactamases. VIII. Analytical chromatofocusing of chromosomal cephalosporinases from four Klebsiella strains. 350 Jan 79

The susceptibility testing of 7,745 recent clinical isolates from four medical centers showed Ro 19-5247 to be eight- to greater than 64-fold more active than cephalexin against the Enterobacteriaceae. Ro 19-5247 was comparable with cephalexin in anti-staphylococcal activity (MIC50, 4.0 micrograms/ml) and fourfold more active than cefixime. None of the oral cephalosporins were effective (MIC50, greater than 32 micrograms/ml) against enterococci, Pseudomonas aeruginosa and P. maltophilia. beta-lactamase hydrolysis experiments failed to demonstrate significant Ro 19-5247 inactivation by ten commonly encountered chromosomal- or plasmid-mediated enzymes (P99, K1, K14, TEM, CARB, OXA).
 ...
PMID:Antimicrobial activity of Ro 19-5247 (T-2525), a new oral cephalosporin, tested against 7,745 recent clinical isolates. 356 94

A total of 4093 non-replicate Pseudomonas aeruginosa isolates supplied by 10 French hospitals from September 1981 to August 1983 was examined for susceptibility to ticarcillin (TIC) and to 11 other beta-lactam antibiotics. Overall incidence of TIC-resistance was low (20.9%) but variable between hospital, unit and culture site and primarily mediated by a constitutive beta-lactamase as observed by iodometric detection (66.3%). As suggested by analytical isoelectrofocusing on gel, PSE-1 (CARB-2) and OXA types were predominant but new types appeared. The comparative in vitro activities of 12 antipseudomonal beta-lactams appreciated by microtiter MICs with an inoculum of 10(5) CFU were established according to phenotype: TIC-susceptible, TIC-R with a constitutive beta-lactamase (PSE-1, OXA-1, OXA-2, OXA-3, PSE-2 and a new type, TEM-1 and TEM-2 and derepressed cephalosporinase) or without detectable activity. Different patterns of resistance were demonstrated, but imipenem, ceftazidime and aztreonam were the most active antibacterial agents.
 ...
PMID:beta-Lactamases of Pseudomonas aeruginosa and susceptibility against beta-lactam antibiotics. 392 Dec 65

Acquired resistance of Pseudomonas aeruginosa to beta-lactam antibiotics, e.g. ticarcillin, has the following characters: The incidence of ticarcillin-resistant strains is about 21% but it varies with hospitals from 10.9 to 35.1%. Resistance is predominantly due to beta-lactamases, which are produced by two-thirds of the strains (64.4% in 1982, 67.9% in 1983). The presence of beta-lactamase positive strains is dependent upon the type of patient, the hospital unit (e.g. urology or burns) and the nature of the specimen collected. Most beta-lactamase positive strains spontaneously produce one single penicillinase of the CARB (53.8%), OXA (30.5%) or TEM (8.7%) type. New types of beta-lactamases may develop and hydrolyse beta-lactam antibiotics such as ticarcillin, azlocillin, cefoperazone or cefsulodin. With beta-lactam antibiotics (cefotaxime, moxalactam, ceftazidime) that resist hydrolysis, bacterial resistance is due to production of a constitutive beta-lactamase of the cephalosporinase type. This enzyme has recently appeared and its incidence is low (6.8%). Associated beta-lactamases (e.g. penicillinase plus cephalosporinase) are exceptional.
 ...
PMID:[Distribution of constituent beta-lactamases in Pseudomonas aeruginosa]. 623 93


<< Previous 1 2 3 4 Next >>