Background There is a growing interest in studying the relationship between intrinsic resistance and biofilms resistance to drugs. However, the relationship still remains unclear in the macroscopic bacterial growth. Our study is to illuminate the change of bacterial drug resistance of gyrA mutant and active efflux pump during the development of Pseudomonas aeruginosa (P. aeruginosa) biofilms. Methods The strains of type Ⅱ topoisomerase gene mutant (gyrA mutant) and multidrug resistance (MDR) efflux pump were clinical isolates and detected by polymerase chain reaction (PCR). The process of bacterial biofilms development was observed by scanning electron microscope. Triparental mating experiments were performed to transfer report gene of green fluorescent protein (GFP) into P. aeruginosa biofilms strains and followed by analysis of bacterial survival rate between intrinsic resistance and biofilms resistance.Results The fluorescent strains with pGFPuv could develop mature biofilms on Teflon surface. Before a period of 72 hours, the survival rate of biofilms bacteria and intrinsic resistance strains in ciprofloxacin solution was significantly different (P<0.05). The survival number of intrinsic resistance strains (gyrA mutation and active efflux pump) was illustriously higher than biofilm strain in the initial stage of biofilms development. After 72 hours incubation, there was no clearly difference between mutants and biofilms strains in the survival rate (P>0.05). The carbonyl cyanide m-chlorophenylhydrazone and azithromycin could significantly reduce the drug resistance of biofilm strains and efflux pump strains.Conclusions In the development of P. aeruginosa biofilms, the strains of gyrA mutation and MDR efflux could be conferred with new level of drug resistance. When co-cultured mutated strains with biofilm strains, biofilms may play a major role in bacterial resistance. But after 72 hours incubation (a mature biofilms had been developed), there was no clearly difference between the number of mutant strains and biofilm strains.

BACKGROUNDThere is a growing interest in studying the relationship between intrinsic resistance and biofilms resistance to drugs. However, the relationship still remains unclear in the macroscopic bacterial growth. Our study is to illuminate the change of bacterial drug resistance of gyrA mutant and active efflux pump during the development of Pseudomonas aeruginosa (P. aeruginosa) biofilms.

METHODSThe strains of type II topoisomerase gene mutant (gyrA mutant) and multidrug resistance (MDR) efflux pump were clinical isolates and detected by polymerase chain reaction (PCR). The process of bacterial biofilms development was observed by scanning electron microscope. Triparental mating experiments were performed to transfer report gene of green fluorescent protein (GFP) into P. aeruginosa biofilms strains and followed by analysis of bacterial survival rate between intrinsic resistance and biofilms resistance.

RESULTSThe fluorescent strains with pGFPuv could develop mature biofilms on Teflon surface. Before a period of 72 hours, the survival rate of biofilms bacteria and intrinsic resistance strains in ciprofloxacin solution was significantly different (P < 0.05). The survival number of intrinsic resistance strains (gyrA mutation and active efflux pump) was illustriously higher than biofilm strain in the initial stage of biofilms development. After 72 hours incubation, there was no clearly difference between mutants and biofilms strains in the survival rate (P > 0.05). The carbonyl cyanide m-chlorophenylhydrazone and azithromycin could significantly reduce the drug resistance of biofilm strains and efflux pump strains.

CONCLUSIONSIn the development of P. aeruginosa biofilms, the strains of gyrA mutation and MDR efflux could be conferred with new level of drug resistance. When co-cultured mutated strains with biofilm strains, biofilms may play a major role in bacterial resistance. But after 72 hours incubation (a mature biofilms had been developed), there was no clearly difference between the number of mutant strains and biofilm strains.

Biofilms ; drug effects ; Carbonyl Cyanide m-Chlorophenyl Hydrazone ; pharmacology ; Ciprofloxacin ; pharmacology ; DNA Gyrase ; genetics ; Drug Resistance, Bacterial ; Mutation ; Pseudomonas aeruginosa ; drug effects ; genetics

OBJECTIVE: To observe the clinical effect of acupuncture at sphenopalatine ganglion combined with conventional acupuncture for episodic cluster headache (CH). METHODS: One hundred and eighty patients with episodic CH were randomly divided into a combined group (60 cases, 3 cases dropped off)，an acupuncture group (60 cases, 2 cases dropped off) and a sphenopalatine ganglion group (60 cases, 2 cases dropped off and 1 case was removed). The patients in the acupuncture group were treated with conventional acupuncture at Touwei (ST 8), Yintang (GV 24⁺), Yangbai (GB 14), Hegu (LI 4), etc., once a day, 6 times a week. The patients in the sphenopalatine ganglion group were treated with acupuncture at sphenopalatine ganglion, once every other day, 3 times a week. On the basis of the conventional acupuncture, the combined group was treated with acupuncture at sphenopalatine ganglion once every other day. Two weeks were taken as a course of treatment, and 3 courses of treatment were required in the 3 groups. The score of visual analogue scale (VAS), the number of headache attacks per week, the duration of each headache attack and the score of migraine-specific quality of life questionnaire version 2.1 (MSQ) were observed before and after treatment and in follow-up of 3 months after treatment. The clinical efficacy of each group was compared. RESULTS: After treatment and in follow-up, the VAS score of headache, the number of headache attacks per week, the duration of each headache attack, and each various scores and the total score of MSQ of each group were lower than those before treatment (P<0.01). Except that the number of headache attacks per week in the combined group was lower than the sphenopalatine ganglion group (P<0.01), other indexes in the combined group were lower than the other two groups (P<0.05, P<0.01). The total effective rate in the combined group was 93.0% (53/57), which was higher than 75.9% (44/58) in the acupuncture group and 73.7% (42/57) in the sphenopalatine ganglion group（P<0.05, P<0.01). CONCLUSION Acupuncture at sphenopalatine ganglion combined with conventional acupuncture could reduce the degree of pain in patients with episodic CH, reduce the number and duration of headache attacks, and improve the quality of life of patients. It is more effective than simple conventional acupuncture or acupuncture at sphenopalatine ganglion alone.
Acupuncture Points ; Acupuncture Therapy ; Cluster Headache/therapy* ; Headache/therapy* ; Humans ; Quality of Life ; Treatment Outcome