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The research background Pseudomonas aeruginosa (Pseudomonas aeruginosa, PA) and Acinetobacter the bacilli (Acinitobacter baumannii) on behalf of non-fermenting bacteria could easily cause infections in hospitals, with the replacement of antibiotics and a large number of applications in recent years, immunosuppressants and a variety of invasive diagnostic and therapeutic means, hospital infection caused by both bacteria gradually increased. While antibiotic resistance is a growing problem in recent years, more is the emergence of polymyxin resistant Pseudomonas and Acinetobacter antibiotics, including penicillins, cephalosporins, single-lactams, fluoro- quinolones, aminoglycosides and carbon green enzyme alkenes antimicrobial resistant strains at the same time, the pan-resistant strains (Pandrug-resistant major strains). All commercially available antibiotics except polymyxin its totally ineffective, patients, once infected, often allows the clinician to do nothing. Resistant Pseudomonas aeruginosa and Acinetobacter bacilli complex mechanisms of resistance, resistance mechanisms include the following: ⑴ genomic structural gene mutations, insertions or deletions. (2) to change the target of the drug. (3) produce inactivated enzyme: ultra-broad spectrum β-lactamase AmpC beta-lactamase enzymes, metallo-β-lactamase enzymes. These mechanisms of resistance to participate in the formation of bacterial resistance. The main contradiction effective low rate of new drug resistant strains gradually adjusted regimen and potential antimicrobial activity of existing other classes of drugs before the listing of the new effective drugs, one main research directions. Have reported different calcium channel blockers associated with levofloxacin vary the effect of the drug-resistant Pseudomonas aeruginosa, which amlodipine resistant Pseudomonas aeruginosa. Also reported that macrolide drugs with other drugs such patients can improve clinical cure rate of clinical P. aeruginosa infection. However, for the antibacterial effect of these drugs as well as mechanisms of bacterial resistance, by what mechanism works have not been reported. Therefore it is necessary to this deeper research, in order to provide a theoretical basis for the treatment of multi-drug resistant non-fermenting bacteria infection. Objective research macrolides, and the calcium channel blocker amlodipine intervention role in pan-resistant strains in vitro susceptibility testing and research associated with the relevant mechanisms of resistance, and further establish the pneumonia model, its combined treatment effects were observed for the treatment of pan-resistant strains of infections caused provide a theoretical basis. Method 1. VITEK-2 analyzer identification of microorganisms, according to the CLSI (2009 Edition) standard screening 19 pan-resistant Pseudomonas aeruginosa and six pan-resistant boydii 25 pan-resistant strains of Acinetobacter agar dilution method and checkerboard dilution method the joint susceptibility testing, ceftazidime, amikacin and ciprofloxacin different drug combinations were dubbed in low concentrations the group (1MICs) and high-dose group (2MICs) azithromycin concentration 0.4mg / ml for the low concentration group, 3.9mg/ml high concentration group. Another group of different combinations of drug-containing plates added the amlodipine intervention, amlodipine eventually dubbed by instructions equivalent to conventional medication after the plasma concentration of 3.0ng/ml. 2 E-TEST 25 pan-resistant strains of metal enzyme assays. Real-time PCR technology detection, including: MexAB-OprM MexCD-OprJ MexEF-OprN and MexXY-OprM active efflux system of 25 pan-resistant strains. Select various drug combinations in vitro susceptibility testing active at the same time a Pseudomonas aeruginosa mouse pneumonia model at 6 hours after infection administration control group were injected 0.5ml saline treatment group with ceftazidime A Mika Star ciprofloxacin, and ceftazidime amikacin ciprofloxacin amlodipine two groups regimen after three days of continuous treatment, according to the lung tissue homogenates bacterial counts and pathological findings evaluated the efficacy. Results 1. Ceftazidime with amikacin and ciprofloxacin associated with, the synergistic ratio occurred ciprofloxacin group to 36.8%, the amikacin group was 84.2%, the high concentration of a combination of ceftazidime agar dilution method, respectively, and A Mika Star, azithromycin, doxycycline and ciprofloxacin joint, its efficiency were 0, 0,8% and 12%; adding the calcium channel blocker amlodipine (3.0ng/ml) after the intervention, its efficiency were 0, 0,20%, 28% (P = 0.003). Low concentration group difference was not statistically significant. 2. The metal enzyme test results separate 19 pan-resistant Pseudomonas aeruginosa strains metalloenzymes positive 8, 11 metalloenzymes negative; six pan-resistant Acinetobacter subtilis strain the metalloenzymes positive 2 4 metalloenzymes negative, each drug combination of ciprofloxacin and doxycycline group is part of the metal-negative strains, while of metalloenzymes positive strains for drug The combinations are invalid. Efflux pump gene expression of the combined group analysis and comparison, all due to to join effective strain amlodipine besylate intervention, MexA have high expression, high expression of of MexC, MexE, and MexX the part, and for ammonia is added after the intervention of amlodipine invalid and metal enzyme-positive strains, efflux pump genes have different degrees of high expression. 4. Vivo drug susceptibility test showed group regardless of whether the amlodipine intervention, bacterial clearance compared with control group difference was statistically significant (P <0.05), while the comparison between the two-drug group, the difference was not statistically significant . Conclusion 1. Adding amlodipine intervention doxycycline group, the combination of high concentrations of ciprofloxacin group on the part of the metal-negative strains significant inhibitory effect MexA have high expression strain obvious, while on the metalloenzymes positive strains invalid. Vitro sensitive and insensitive strains between the amount of the expression of the efflux pump undifferentiated, amlodipine, and can not affect the expression of the pan-resistant strains of the efflux pump genes, may only be achieved through the inhibition of efflux pump activity Antibacterial effect. Pan-resistant Pseudomonas aeruginosa infection pneumonia model, combined with the in vitro susceptibility testing of single-drug resistant antibacterial drugs, there is still some cleanup role of bacteria, but the added Amlodipine intervention is not displayed obvious treatment effect.
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