Objective To investigate whether Pseudomonas aeruginosa pvdQ( PA2385 ) gene reveals altered antibiotic susceptibility under swarming conditions. Methods The plasmid pME6032 with pvdQ gene was constructed and identified, then transformed into Pseudomonas aeruginosa PAO1 by the electroporation, building pvdQ overexpression strain. Using the same method building pME6032-PAO1 strain.Bacteria were inoculated in LB overnight , measuring the colony diameter of the swarming zone . Results Strains of pvdQ overexpression was successfully constructed by real-time PCR. Comparison of two strains of the swarming motility of change in diameter: The result showed that PAO1 and pvdQ overexpression strains can both improve the antibiotics resistance. Swarmer cells of pvdQ overexpression strain exhibited a 2- to 4-fold increase in antibiotic resistance toward ceftazidime,ciprofloxacin, meropenem and polymyxin B compared to PAO1 on BM2-swarming agar plates. Conclusion pvdQ gene played an important role in elevating the antibiotics resistance, which through prarticipated in the swarmer cell differentiation.

Objective To investigate the effect and mechanism of siHybrids technique on inhibiring the efflux pump gene mexB of Pseudomonas aeruginosa PAO1 in vitro. MethodsTargeting the efflux pump gene mexB of Pseudomonas aeruginosa PAO1 ,we designed and synthesized three siHybrids molecule and one negative scamble siHybrids molecule. Pseudomonas aeruginosa PAO1 were intervened by the siHybrids molecules in 50 nmol/L, respectively. And the experiments were made of control groups[blank and scamble (sc) -001]and intervened groups[siHybrids( si ) -001, siHybrids( si ) -002 and siHybrids(si) -003]of Pseudomonas aeruginosa PAO1. The targeting efflux pump gene mexB mRNA expressions of Pseudomonas aeruginosa PAO1, including all groups, were measured by real-time PCR in 12 h and 24 h after interference in vitro. Further, the minimal inhibitory concentration (MIC) of chlormycetinCP, erythrocin( EM ), levofloxacin ( L-OFLX), ceftazidime ( CAZ), meropenem (MER) to those groups were detected by using Mueller-Hinton broth dilution before and after interference. ResultsThe relative mexB mRNA amounts of Pseudomonas aeruginosa PAO1 intervened by different siHybrids were not much more different from each other after 12 h,but the expression of mexB mRNA of the intervened group ( si-001 ,si-002 ,si-003 ) was much lower than control groups after interference for 24 h. The relative mexB mRNA amounts, comparing 12 h with 24 h, we would find the blank control and negative control submit escalating trend. And the intervened control ,three different siHybrids were all with a downward tendency. However, in presence of 50 nmol/L siHybrids, the minimal inhibitory concentration(MIC) of CP, EM, L-OFLX, CAZ, MER to those controls were not much more different before and after interference. Conclusion On level of the mRNA expressions, siHybrids could inhibit the efflux pump gene mexB of Pseudomonas aeruginosa PAO1 in vitro, and within 24 h would be able to function effectively. Further, the effect was time-dependent.

Objective To analyze the current status of bacterial spectrum and drug resistance in community-acquired biliary tract infection to provide a basis for clinical medication .Methods The patients with community-acquired biliary tract infection (ex-periment group) and the patients with biliary tract diseases without biliary tract infection (control group) derived from the native ar-ea treated in this hospital from September 2014 to January 2016 were selected .The bile juice was intraoperatively extracted for con-ducting the bacterial culture and drug susceptibility test .Results Thirteen specieses (60 strains) of bacteria were isolated in the ex-periment group .The top 3 specieses were Escherichia coli (35 .0% ) ,Klebsiella pneumonia (21 .7% ) and Enterobacter cloacae (10 .0% ) .Eight specieses (13 strains) of bacteria were isolated in the control group .The top 3 specieses were Escherichia coli (30 .8% ) ,Klebsiella pneumonia(15 .4% ) and Lactococcus garvieae (15 .4% ) .The proportions of drug resistant strains in the two groups were 95 .0% and 84 .6% respectively (P>0 .05) .The proportions of multiple drug resistant strains in the two groups were 30 .0% and 7 .7% respectively(P>0 .05) .The occurrence rates of multiple drug resistance in the top 3 specieses of bacteria in the experiment group were 61 .9% ,7 .7% and 16 .7% respectively .Conclusion The bacterial spectra of community-acquired acute bili-ary tract infection in the native area are dominated by Gram negative bacteria .The total bacterial drug resistance is serious ,but the drug resistance situation in different bacteria pathogens is different .