Preliminary Study On Adhesion Molecular MAdCAM-1/VCAM-1 From Mastitis In Dairy Cows

Objective:To study the prevalence of the infection of Pseudomonas aeruginosain our hospital and investigate the drug resistance of pseudomonasaeruginosa in the last two years. The genotypes of metallo-β-lactamaseswere characterized by using polymerase chain reaction and DNAsequence analysis. To study the main genotype and distribution ofmetallo-β-lactamases.Methods:Total 536 Pseudomonas aeruginosa isolates identified by MicroScanWalkaway 96 from 2010 to 2011. Antibiotic sensitivity detected by K-Bdisk diffusion and NC31 panel of Walkaway 96. Date were analyzed byWHONET5.5 software. Metallo-β-lactamases were screened byDouble-Disk synergy test in 71 imipenem-resistant pseudomonasaeruginosa isolates. The genotype of Metallo-β-lactamases includingIMP-1,IMP-2,VIM-1,VIM-2,SPM-1 and NDM-1 were performed byPCR and DNA sequence analysis.Results:1. Drug resistance of Pseudomonas aeruginosa : The isolation of Pseudomonas aeruginosa strains was increasingfrom 2010 to 2011, but drug resistance rate declined.Cefoperazone/sulbactam was the most sensitive antimicrobial agent,followed by amikacin,levofloxacin,ceftazidime,piperacillin/tazobactam,imipenem, but resistance rate of imipenem hadbeen more than 20%.2. Distribution in the departments and the specimens of Pseudomonasaeruginosa:From 2010 to 2011, the isolation rate of Pseudomonas aeruginosafrom sputum was the highest, accounted for 79.8% and 78.6%, followedis pus, accounted for 17.4%,17.3%; The most isolation rate of thedepartments was Neurosurgery , accounted for 34.3%,25.5%, followed isRespiratory medicine, accounted for 23.0%,15.3%.3. Screening results of the metallo-β-lactamasesTotal 28 metallo-β-lactamases phenotype positive strains were gotby Double-Disk Synergy Test in 71 imipenem resistant Pseudomonasaeruginosa isolates.4. The results of metallo-β-lactamases genotype:Total 10 strains were producing IMP-1 type metallo-β-lactamases in28 strains of metallo-β-lactamases phenotype positive strains, other typesof metallo-β-lactamases had not been found .Conclusion: The isolation of Pseudomonas aeruginosa strains was increasingfrom 2010 to 2011, but drug resistance rate declined.Cefoperazone/sulbactam was the best activity antibiotic against toPseudomonas aeruginosa, and resistance rate of imipenem was more than20%. The starin of Pseudomonas aeruginosa was most commonly isolatedfrom sputum, the most isolation department was neurosurgery.Producing metallo-β-lactamases was the main mechanisms of thecarbarpenem resistant Pseudomonas aeruginosa, IMP-1 is the mostcommon metallo-β-lactamases genotype.