Aim To identify the extended-spectrum ?-lactamases(ESBLs) gene in Klebsiellae pneumoniae isolates with qnr gene.Methods Antimicrobial agents susceptibilities were determined with standard agar dilution procedure on Mueller-Hintonagar and 3 isolates with qnr gene were confirmed as ESBLs producing strains by NCCLS Confirmatory Test.The partial blagene of ESBLs producing isolates were detected by PCR using universal primers for TEM,SHV,CTX-M-1group,CTX-M-2 group,CTX-M-13group,OXA-1group,OXA-2 group,OXA-10 group,PER-1 and VEB-1,respectively.At the same time,Class 1 integrase gene was also detected by PCR.The entire blaCTX-M-13group,blaTEM,blaOXA-1group were amplified by PCR using the primers outside the Open Reading Frame(ORF) of these ?-lactamases.The PCR products were also directly sequenced and analyzed;the clinical isolates of ESBLs producers were detected by PFGE. Results 3 Klebsiellae pneumoniae isolates with qnr gene were ESBLs producers and they produced CTX-M-14 ESBLs and TEM-1 ?-lactamases.1 isolate simultaneously produced OXA-1?-lactamases,and 3 isolates carried class 1 integron.Besides quinolones,ESBL producers were also resistant to most ?-lactams,and PFGE patterns of two isolates were same.Conclusion 3 Klebsiellae pneumoniae isolates with qnr gene produced CTX-M-14 ESBLs,which caused their multi-resistance,and clone spread was found in them.More attention should be paid to detect those strains.

Objective To investigate the resistance to fluoroquinolones and amikacin in escherichia coti isolates. Methods ESBLs-producers were detected by CLSI phenotypic confirmatory test and susceptibilities were tested by agar dilution method. Results 33. 8% of 361 isolates were ESBLs-producers. The resistant rate of ciprofloxacin,levofloxacin, amikaxin was 93.4%, 90.9%, 13.1% in ESBLs-produeers, and that was 69.5%,68.6 %, 19.7 % in non-ESBLs-producers, respectively. Conclusion Amikaxin is active against most escherichia coli isolates; those isolates are highly resistant to fluoroquinolones, especially, in ESBLs-producers.

Objective To investigate the ESBL gene in a Klebsiella pneumoniae strain isolated from a patient in Huashan Hospital, Shanghai. Methods ESBL gene in the transconjugant from Klebsiella pneumoniae isolate was amplified by PCR. The PCR products were cloned into pHSG398 vector. The antibiotic susceptiblity and ?-lactamases activity of the clone strain were tested; The PCR product was sequenced and analyzed. Results The ESBL gene was identified as CTX-M-12 gene and CTX-M-12 is much more active against cefotaxime than against ceftazidine.Conclusions A clinical isolate of Klebsiella pneumoniae k99-442 isolated from a patient in Huashan Hospital, Shanghai produced ESBL type CTX-M-12 which caused this isolate resistant to most ?-lactams.

OBJECTIVE To investigate the prevalence of meticillin-resistant Staphylococcus (MRS) isolates in Staphylococcus auricularis and S. hominis and detect their drug resistance. METHODS MRS isolates were detected by cefoxitin disc test and susceptibilities were tested by agar dilution method. RESULTS 94.7% and 91.7% MRS isolates were in S. auricularis and S. hominis. MRS strains were resistant to most of antimicrobial agents. There were no isolates resistant to vancomycin and teicoplanin. CONCLUSIONS MRS isolates are highly prevalent in S. auricularis and S. hominis with resistance to most of antimicrobial agents.

OBJECTIVE To investigate the prevalence of meticillin-resistant Staphylococcus haemolyticus(MRSH)and resistance in S.haemolyticus isolates. METHODS MRSH was detected by cefoxitin disc test and susceptibilities were tested by agar dilution method. RESULTS There were 86.4% of MRSH isolates.MRSH was highly resistant to penicillin,cefazolin,cefuroxime,ceftriaxone,tetracycline,ciprofloxacin,and clindamycin.The resistance rate to amikacin,rifampicine and chloramphenicol was 16.9%,11.2% and 28.1%,respectively.All isolates were susceptible to vancomycin and teicoplanin.Except for tetracycline,amikacin,rifampicin,and chloramphenicol,the resistant rate to other antimicrobial agents was significantly higher in MRSH than in MSSH. CONCLUSIONS MRSH is mostly occupied in S.haemolyticus isolates and resistant to most of antimicrobial agents.More attention should be paid to survey and detect these strains.

Objective To study the biologic characteristics of the new qnr gene subtype and multi-drug resistant mechanism in a clinical isolate of Klebsiella oxytoca.Methods We cloned and expressed the qnr gene,?-lactamase and integrase genes were detected by PCR.Results Susceptibility of transformant containing qnr gene against common fluoroquinolones was 3~25 times lower than recipient stain,but drug-resistance was 4~256 times lower than the clinical isolate.KLUC-1,TEM-1 and OXA-30 genes were also found in the isolate.Conclusions qnr gene can raise the drug-resistance to fluoroquinolones slightly. There are multiple drug-resistant genes in the strain containing the qnr gene.

OBJECTIVE To investigate the resistance of Pseudomonas aeruginosa strains to 5 ?-lactams.METHODS Susceptibility of 218 P.aeruginosa strains isolated from Anhui Province in 2005 to ceftriaxone,cefotaxime,ceftazidime,aztreonam,and piperacillin were tested by agar dilution method.RESULTS The resistance rate to ceftriaxone,cefotaxime,aztreonam,piperacillin,and ceftazidime were 59.2%,57.3%, 56.0%,51.8%,and 39.0%,respectively.There was statistically significant difference between ceftazidime and other 4 ?-lactams(P0.05).CONCLUSIONS Ceftazidime is the most susceptible antibiotic to P.aeruginosa strains among 5 ?-lactams tested.

OBJECTIVE To analyze the drug resistance of 141 clinical strains of Acinetobacter baumannii to 15 kinds of antimicrobial agents for the rational application of antimicrobial agents.METHODS All 141 strains of A.baumannii isolates were tested for minimal inhibitory concentration(MIC) to 15 kinds of antimicrobial agents included meropenem,imipenem,piperacillin,and so on using agar dilution method.RESULTS The lowest resistance rate of A.baumannii to the antimicrobial agents was to imipenem(22.7%),then was to meropenem and cefoperazone/sulbactam.The highest resistance rate was tetracycline(81.5%).The resistance rate to other antimicrobial agents was to about or more than 50%.CONCLUSIONS Most of A.baumannii isolates are susceptible to meropenem,imipenem,and cefoperazone/sulbactam and resistant to other antimicrobial agents,therefore,we should enhance to this kind of isolates detection.

OBJECTIVE To investigate the resistance and molecular epidemiology of Pseudomonas aeruginosa isolated from ICU. METHODS Susceptibility of P. aeruginosa isolates to 14 antimicrobial agents were tested by microScan WalkAway-40 system,and Molecular typing was analyzed by enterobacterial repetitive intergenic consensus(ERIC-PCR). RESULTS The lowest resistance rate of P. aeruginosa to the antimicrobial agents was to ceftazidime (27.3%),then to cefepime (45.5%). The highest resistance rate was to cefotaxime (100.0%) and the resistance rate to other antimicrobial agents was more than 60.0%. Patterns of ERIC-PCR were same in 5 strains of P. aeruginosa. CONCLUSIONS P. aeruginosa isolated from ICU is resistant to most of antimicrobial agents and clone spread is found in them. We should enhance detection and surveying of these isolates.

OBJECTIVE To investigate the prevalence of extended-spectrum ?-lactamases (ESBLs) and antibiotic resistance in Klebsiella pneumoniae isolates.METHODS ESBLs-producers were detected by CLSI phenotypic confirmatory test and susceptibilities were tested by agar dilution method.RESULTS 41.1% Of isolates were ESBLs producers in those isolates. ESBLs producers were highly resistant to piperacillin,cefazolin,cefuroxime,fluoroquinolones,chloramphenicol,SMZ-TMP and amikacin. The resistant rate to piperacillin-tazobactam,and ceftazidime was 26.3% and 34.2%. None was resistant to imipenem and meropenem in ESBLs producers. Except for carbapenems,the resistant rate to other antimicrobial agents was significantly higher in ESBLs producers than non ESBLs producers.CONCLUSIONS With resistance to most of antimicrobial agents,ESBLs-producers are highly prevalent in K. pneumoniae isolates,more attention should be paid to monitor these strains.