OBJECTIVE:To investigate the resistance and prevalence of ?-lactamases in clinical isolates of P.aeruginosa and guide rational use of antibacterial agents.METHODS :MICs of 12 kinds of antibiotics to 70 P.aeruginosa isolates were tested by agar dilution.AmpC ?-lactamases and ESBLs were detected in 20 multi-drug P.aeruginosa strains by three-dimensional test.ESBLs genotypes were analyzed by PCR amplification and product sequencing.RESULTS:Imipenem,amikacin and ciprofloxacin had good activity against P.aeruginosa.Three-dimensional test showed that 2 strains possessed ESBLs,6 strains hyperexpressed AmpC ?-lactamases in 20 srains.PCR amplification and DNA sequencing showed that 4 strains with blaTEM,2 strains produced TEM-1,1 strain produced TEM-29,1 strain produced TEM ?-lactamase named as TEM-147 by GenBank with only one amino acid substitutionfrom TEM-29.CONCLUSIONS:Attention must be paid to the detection of ESBLs in P.aeruginosa which may cause clinical infections.Carbapenems,amikacin or ciprofloxacin can provide effective therapy for such infections.

OBJECTIVE:To observe the relationship between gyrA gene mutations of the clinical isolates of Pseudomonas aeruginosa and quinolone resistance and to evaluate the feasibility of analyzing gyrA gene mutations using PCR-RFLP-SSCP.METHODS:With gyrA gene order of the clinical isolates of Pseudomonas aeruginosa taken as target sequence,gyrA gene mutations in strain ATCC 27853 and 16 clinical isolates of Pseudomonas aeruginosa were analyzed contrastively using PCR,PCR-RFLP,PCR-SSCP,and DNA sequencing.RESULTS:Of the total 8 ciprofloxacin resistant Pseudomonas aeruginosa,6 strains showed single point ACC→ ATC mutation in the gyrA gene at codon 83,leading to amino acid substitution of Thr83→Ile.SacⅡ digestion fragment of the PCR amplified products in gyrA gene was in line with the sequencing results.SSCP showed that the banding patterns of all strains were different from that of strain ATCC 27853 except 2 strains.CONCLUSION:The molecular mechanism of the quinolone resistant Pseudomonas aeruginosa isolated from clinics was manifested as mutations in the gyrA gene at codon 83.The results showed that PCR-RFLP-SSCP is a rapid and accurate method for the detection of basyl variation in gyrA in quinolone resistant Pseudomonas aeruginosa.

[ ABSTRACT] AIM:To investigate the change of phosphorylation of tau protein and expression of cyclooxygenase 2 ( COX-2) in colon submucosal neurons of enteric nerve system in inflammatory bowel disease ( IBD) rats induced by tri-nitrobenzene sulfonic acid (TNBS).METHODS:Male rats (n=30) were randomly assigned to 3 groups (n=10 each):control group, IBD group and TNBS group.The IBD rats were induced by TNBS+ethanol enema for 14 d.The control and TNBS rats were given an equal volume of saline and TNBS, respectively.The general situation and the histopathologic change of the rat colon were observed.Immunofluorescence was used to check the change of phosphalated tau protein and COX-2 expression in the submucosal neurons of the colon.The expression of COX-2 and phosphorylated tau231 and tau262 in the rat colon submucosal neurons was observed by double immunofluorescence staining.RESULTS:Compared with con-trol group, the number of neurons in the colon of IBD rats decreased obviously and the expression of phospholated tau231 and tau262 was significantly increased.The number of neurons in the colon of TNBS rats showed no significant difference compared with control rats.The rat neurons in control group and TNBS group did not express COX-2.COX-2 expression was observed in the nucleus and cytoplasm of colonic neurons in IBD rats, which showed significantly different from control and TNBS rats.CONCLUSION:The decreased neurons in the enteric nerve system of IBD rats might be associated with the phosphorylation of tau protein and the expression of inducible COX-2.

Aim To investigate the effects and possible mechanisms of kaemperol in the rats with chronic cere-bral ischemia.Methods Chronic cerebral hypoperfu-sion model was produced by permanent occlusion of bi-lateral common carotid arteries (2VO)in rats.After KAE treatment,the rats underwent Morris water maze and prehensile traction test.Neuronal morphology was observed using Nissl and HE staining.The activity of SOD and the content of MDA in brain tissue were de-termined.The DJ-1 protein expression was assayed by Western blot.Results Compared with 2VO model group,KAE significantly improved learning and memo-ry and the grasping ability.In addition,KAE signifi-cantly reduced brain tissue pathological injury induced by 2VO. Furthermore, KAE significantly increased SOD activity and enhanced antioxidant protein DJ-1 ex-pression in brain tissue.Conclusions KAE could sig-nificantly attenuate the cognitive impairment,limb bal-ance dysfunction and pathological injury in rats with chronic cerebral ischemia.The mechanism may be re-lated to improving the antioxidant system in vivo.

Objective To study the sleep improvement function of DHA-PC.Methods The mice were randomly divid-ed into control, vehicle, DHA+Lecithin (60+200 mg/kg) and DHA-PC(50,100,200 mg/kg) groups.Ten mice were enrolled in each group .The mice of control were administered with normal food , the vehicle group was orally given normal saline at the dosage of 0.2 ml/10 g, while both DHA-PC and DHA+Lecithin were orally given corresponding drugs at the dosage of 0.2 ml/10 g.All the groups were treated for 30 days except control group .The direct sleep-inducing test, the test of lengthening sleep time induced by pentobarbital sodium , the test of pentobarbital sodium subthreshold-hypnosis and the test of barbital sodium sleep latency were conducted to observe the inductive effect of DHA -PC.Results Neither the effect on mice body mass nor directly-induced sleep was observed .DHA-PC (50,100, and 200 mg/kg) could prolong sleep time to (56.2 ±13.7),(57.9 ±25.4) and(64.1 ±18.4) min, respectively,compared to vehicle(32.9 ±10.8)min (P<0.05).DHA+Lecithin could not prolong sleep time (38.6 ±11.7)min compared to (32.9 ±10.8)min of vehicle.There was significant difference compared with DHA-PC at the dosage of 200 mg/kg (64.1 ±18.4)min (P<0.05).DHA-PC (200 mg/kg) enhanced pentobarbital sodium subthreshold-hypnosis (70%) compared to vehicle (10%) (P<0.05),so did DHA+Lecithin (60%) compared to vehicle (10%) (P<0.05).Both DHA-PC (200 mg/kg)[(22.9 ±4.1)min ] and DHA+Lecithin [(19.5 ±2.7) min ]could shorten sleep latency compared to vehicle (31.3 ±6.9) min(P<0.01), and the sleep latency of DHA +Lecithin (19.5 ±2.7) min was shorter than that of DHA-PC(50,100 mg/kg).Conclusion DHA-PC has some effect some sleep improvement in mice .