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Objective To evaluate the characteristics of the PREVI Isola automated plate streaker (bioMérieux,SA).Methods 80 respiratory tract specimens,70 sterile fluids,52 stools,69 swabs,12 cerebrospinal fluids and 80 urines were collected in Peking Union Medicd College Hospital.Specimens were processed with manual streaking and PREVI Isola system.PREVI Isola system were evaluated comparing to the manual streaking.The quality of results were analyzed by SPSS 16.0, doing Wilcoxon’s Sign Rank Test for the results of finally isolated species,overall numbers of isolated colonies and semi-quantita-tive of the species were both isolated by the two methods.Results PREVI Isola system was highly automatic,which could select the right plates and stake the bar code on the back of the plate indicating the type of the agar and inoculation time, PREVI Isola system could accurately absorb the liquid specimen and use a novel comb streaking procedure for processing of fluid specimens on standard agar plates,like 17 inoculating loops work together.It also had a good reproducibility.The quali-ty of PREVI Isola system results:As to the finally isolated species,there was significant statistical difference between PREVI Isola system and manual streaking method in respiratory tract and stools specimen,there were more species isolated by manual streaking method than PREVI Isola system.There were no differences between the two methods for the other of specimen types.As to the amount of pure clones of the species were both isolated by the two methods,there were significant statistical differences between the two methods for respiratory tract,sterile fluid and stool specimens.The amount of clones isolated by PREVI Isola system was more than manual streaking method.In semi-quantitative results,there were significant statistical differences between the two methods for respiratory tract and urine specimen,Species had wider distribution of PREVI Isola system than manual streaking method.Inoculation efficiency:if the batch of specimen type was simple (mainly the urine and so on),using the same plates,PREVI Isola system was more efficient than manual streaking method.Howev-er,if the batch of specimen type was complicated,manual method was high-performance.Besides,not all specimen type could be inoculated by PREVI Isola system,such as cerebrospinal fluid,catheter and tissues.Conclusion If the lab had simple specimen type,or utilize the specimen type using the same agar plates to be inoculated together,PREVI Isola system belongs to a good performance automated plate streaker.
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Aim To investigate glucose uptake effects and mechanism of emodin in 3T3-L1 adipocytes. Methods LPS-induced differentiated 3 T3-L1 adipo-cytes were divided into control group and emodin ( 1 , 10, 50 μmol · L-1 ) groups. Then, 6-NBDG uptake and the expression of cell surface GLUT4 , PPARγ, AMPKα1/2 , p-AMPKα1/2 , IRS-1 , p-IRS-1 , Adi-ponectin, chREBP-α and chREBP-β were detected. The ability of 6-NBDG uptake in LPS-induced 3 T3-L1 adipocytes was also evaluated following interference with AMPK inhibitor and PPARγinhibitor, respective-ly. Meanwhile, STZ-induced diabetic rats were ran-domly divided into control group and emodin treatment group. The mRNA expression of Adiponectin and pro-tein expression of cell surface GLUT4 , AMPKα1/2 , p-AMPKα1/2 were measured. Results Compared with the control group, emodin improved the mRNA expres-sion of cell surface GLUT4, Adiponectin, chREBP-αand chREBP-β, and protein expression of cell surface GLUT4 , PPARγ, IRS-1 , p-IRS-1 , AMPKα1/2 and p-AMPKα1/2 in 3T3-L1 adipocytes(P<0. 05). Emodin enhanced 6-NBDG uptake and the uptake of emodin group was both decreased following interference with AMPK inhibitor and PPARγ inhibitor, respectively ( P<0. 05 ) . Emodin also increased the mRNA expression of Adiponectin and protein expression of cell surface GLUT4 , AMPKα1/2 and p-AMPKα1/2 in adipose tis-sue of T2 DM rats ( P <0. 05 ) . Conclusion Emodin can enhance glucose uptake in 3 T3-L1 adipocytes and the mechanism is probably associated with activating Adiponectin and IRS-1 , thereby activating AMPK and PPARγ.
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Aim To investigate the effect of Salidroside on the focal celebral ischemia/reperfusion injury in rats and its underlying mechanism. Methods Adult male Sprague-Dawley rats, weighing 260-300 g, were ran-domly divided into three groups: sham, MCAO, MCAO+salidroside ( Sal ) groups. The rats were sub-jected to local celebral ischemia reperfusion with su- ture-occluded method. The rats of MCAO +Sal group were treated intraperitoneally with salidroside ( 50 mg ·kg-1 ) for 6 days. Neurological deficit testing was performed with Longa’ s Scale. The mRNA expressions of Neun,Nogo-A,and NgR were detected by RT-qPCR in ischemic brain. The protein expressions of Neun, NGF , BDNF , Nogo-A and NgR were determined by Western blot. Results Compared with MCAO group, salidroside significantly improved the neurological defi-cit,promoted the expressions of Bcl-2,Neun,NGF,BD-NF, and inhibited the expressions of Nogo-A, NgR. Conclusion Salidroside can reduce neurological defi-cit, increase the number of Nissl’ s Body and the ex-pression of Neun, and protect rats against focal cele- bral ischemia/reperfusion injury,which may be accom-plished by increasing the expressions of Bcl-2, NGF, BDNF, and inhibiting the expressions of Nogo-A, NgR.
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Aim To investigate the neuroprotective effect of salidroside in MCAO rats. Methods The rats were subjected to middle cerebral artery occlusion with suture-occluded method, and the neurologic injury and infarct size of rats were evaluated. According to the gene chip detected, the protein expressions of caspase-3 , cleaved caspase-3 were determined and the mRNA expressions of IL-6, Vgf, Hba-a2, Hbb-b1, Hbb, CD44, Pnpla2, Slc6a5 and Slc5a7 were tested. Re-sults Compared with MCAO group, salidroside signif-icantly improved the neurological deficit, reduced the infarct sizes, inhibited the expressions of cleaved caspase-3 protein and IL-6 mRNA, promoted the ex-pressions of Vgf, Hba-a2, Hbb-b1, Hbb, and reduced the expressions of CD44 , Pnpla2 , Slc6 a5 and Slc5 a7 . Conclusions Salidroside can reduce the neurological deficit and infarct size, and protect rats against focal cerebral ischemia-reperfusion injury, which may be ac-complished by increasing the expressions of Vgf, Hba-a2, Hbb-b1, and Hbb, and decreasing the expressions of cleaved caspase-3 , IL-6 , CD44 , Pnpla2 , Slc6 a5 and Slc5 a7 .
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Objective To investigate the profile of antimicrobial resistance in clinical isolates from the patients in Peking Union Medical College Hospital during 2012.Methods A total of 6 662 nonduplicate clinical isolates were collected.Disc diffusion test or Kirby-Bauer method and automated systems were employed to study the antimicrobial resistance.The data were analyzed by WHONET 5.6 software according to CLSI 2012 breakpoints.Results Of the 6 662 bacterial strains included in this analysis, gram negative organisms and gram positive cocci accounted for 66.7% (4 446/6 662)and 33.3% (2 216/6 662),respectively. The top 10 most frequently isolated microorganisms were E.coli (17%),P .aeruginosa (11.4%),A.baumannii (11.4%), S.aureus (11.2%),K.pneumoniae (9.2%),E.faecalis (8.4%),E.faecium (4.1%),coagulase negative Staphylococcus (3.3%),E.cloacae (3.1%)and S.maltophilia (3.1%).About 39.9% of the S.aureus strains and 73.4% of the coagulase negative Staphylococcus were methicillin-resistant.No staphylococcal strains were found resistant to vancomycin,teicoplanin or linezolid.A few of vancomycin-or teicoplanin-resistant strains were identified in both E.faecium and E.faecalis.No lin-ezolid resistant strains were found.ESBLs-producing strains accounted for 53.0%,25.7% and 27.0% in E.coli,Klebsiella spp.(K.pneumoniae and K.oxytoca)and P .mirabilis, respectively.The Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 2.6% of these strains were resistant to carbapenems.A few pan-re-sistant strains of K.pneumoniae (0.7%,4/615)were iden-tified.About 20.3% and 13.6% of the P .aeruginosa isolates were resistant to imipenem and meropenem,respectively.P . aeruginosa isolates showed the lowest resistance rate (7.2%)to amikacin.And 72.8% and 75.2% of A.baumannii strains were resistant to imipenem and meropenem.A.baumannii isolates showed relatively low resistance rate to cefoperazone-sulbac-tam (51.2%)and minocycline (30.2%).The prevalence of pan-resistant strains was 43.5% in A.baumannii and 1.4% in P . aeruginosa.Conclusions Bacterial resistance is still increasing,especially pan-resistant A.baumannii strains.It is mandatory to take effective measures to control hospital infections and improve rational antibiotic use.
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Objective To investigate antimicrobial resistance among Streptococcus pneumoniae clinically isolated from 14 teaching hospitals located at different areas in China in 2005-2008 and to give logical guidance for clinical empirical therapy.Methods A total of 1 317 non-repetitive S.pneumoniae isolates in 14 teaching hospitals from 2005-2008 were collected and sent to the central lab for reidentification and susceptibility testing, including 271 isolates collected in 2005, 391 isolates collected in 2006, 363 isolates collected in 2007 and 292 isolates collected in 2008. Most of the isolates were from community-acquired respiratory tract infections, which were isolated from outpatient or emergency department patients with respiratory tract infections or those patients with respiratory tract infections within ≤48 hours hospitalization.The districts where the organisms were isolated include North China, Northeast China, South China, Central and Northwest China and East China.The patients included adults, teenagers and children.The minimum inhibitory concentrations (MICs) or inhibitory zone diameter of 17 antimicrobial agents were determined by Etest method, agar dilution method or disk diffusion method.WHONET5.5 software was used to analyze susceptibility rate, intermediate rate, resistance rate, MIC50 and MIC90.Results Linezolid (100%) and fluoroquinolones (95.2%-99.7%) showed excellent activities against S.pneumoniae.Among β-lactams, amoxicillin-clavulanic acid remained high activities (73.8%-92.1%),followed by penicillin, ceftriaxone and cefepime with year-over-year decrease in activities.The activities of three second-generation cephalosporins were low (36.3%-38.4% in 2008).The activities of erythromycin, azithromycin, clindamycin, trimethoprim/sulfamethoxazole and tetracycline against S.pneumoniae were poor and decreased year over year.The incidence of penicillin non-susceptible S.pneumoniae (PNSP) was increasing especially for PISP (from 4.4% in 2005 to 20.2% in 2008).The incidence of PNSP in North China was low (6.0%), while this value were high in central China and East China (30.1% and 38.7%, separately).The incidence of PNSP in adults (15.7%) was obviously lower than that in children(≤5 years:33.0%) and teenagers (6-17 years:38.2%).Conclusions linezolid and fluoroquinolones showed excellent in vitro activity against S.pneumoniae, followed by penicillin and cephalosporins with year-over-year decrease of activity. Clinicians should pay more attention when using those antimicrobial agents with poor activity against S.pneumoniae, which include macrolides, clindamycin, trimethoprim/sulfamethoxazole and tetracycline.
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Objective To investigate distribution and antimicrobial resistance among nosocomial pathogens from 13 teaching hospitals in China in 2009. Methods Non-repetitive pathogens from nosocomial BSI, HAP and IAI were collected and sent to the central lab for MIC determination by agar dilution method.WHONET5.6 software was used to analyze the data. Results A total of 2 502 clinical isolates were collected. The top three pathogens of BSI were Escherichia coli [27. 1% (285/1 052 )] , coagulase-negutive staphylococcus [12. 6% ( 133/1 052)] and Klebsiella pneumoniae [10. 8% ( 114/1 052)]. The top three pathogens of HAP were Acinetobacter baumannii [28. 8% (226/785)], Pseudomonas aeruginosa [16. 1% (126/785)] and Klebsiella pneumoniae [14.6% (115/785 )] . The top three pathogens of IAI were Escherichia coli[31.0% ( 206/665 )], Klebsiella pneumonia [11.3% ( 75/665 )] and Enterococcus faecium [10. 8% (72/665)]. Against Escherichia coil and Klebsiella spp. , the antimicrobial agents with higher than 80% susceptibility rate included imipenem and meropenem (98. 1%-100% ), tigecycline (95.3%-100% ), piperacillin-tazobactam ( 88.6% -97. 1% ) and amikacin ( 88. 3% -92. 5% ). Against Enterobacter spp. , Citrobacter spp. and Serratia spp. , the susceptibility rates of tigecycline were 93.5% -100% whereas the value of imipenem and meropenem were 92.9% -100%. Other antimicrobial agents with high activity included amikacin ( 85.2% -96. 7% ), pipcracillin-tazobactam ( 82.4% -96.4% ), cefepime ( 79. 6% -96. 7% ) and cefoperazonc-sulbactam (78. 7%-90. 0% ). Polymyxin B showed the highest susceptibility rateagainst Pseudomonas aeruginosa ( 100% ), followed by amikacin ( 81.9% ) and piperacillin-tazobactam (80.1% ). Polymyxin B also showed the highest susceptibility rate against Acinetobacter baumannii (98. 8% ), followed by tigecycline (90. 1% ) and minocycline (72. 0% ). The incidence of carbapenemresistant Acinetobacter baumannii was 60. 1%. The MRSA rate was 60. 2% and the MRSCoN rate was 84. 2%. All Staphylococcus strains were susceptible to tigecycline, vancomycin, teicoplanin and linezolid except for one isolate of Staphylococcus haemolysis with intermediate to teicoplanin. Two Enterococcus faecalis isolates which were intermediate to linezolid and one Enterococcus faecium isolate which was resistant to vancomycin and teicoplanin was found in this surveillance, while the MICs of tigecycline against these three isolates were 0. 032-0. 064 μg/ml. Conclusions Tigecycline, carbapenems, piperacillin-tazobactam,amikacin and cefepime remain relatively high activity against nosocomial Enterobacteriaceae. Pseudomonas aeruginosa exhibite high susceptibility to polymyxin B, while Acinetobacter baumanni shows high susceptibility to polymyxin B and tigecycline. Tigecycline, vancomycin, teicoplanin and linezolid remain high activity against nosocomial gram-positive cocci.
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Objective:To observe the changes of lung index,lung function,regulatory T cells and Foxp3,TGF-β1,Smad3,Smad7 protein expression in adjuvant arthritis(AA) rats,and to investigate the possible mechanism of Foxp3 and TGF-β/Smads signal transduction pathway in reducing lung function.Methods: 24 Wistar rats were randomly divided into normal control group and model group,12 rats in each group.The rats were injected with 0.1 ml Freunds'complete adjuvant to induce inflammation at the part of their rightback foot in model group.On the 48~(th) day post-inflammatory,the swelling degree of toe and arthritis index(AI) were observed.Lung index of the rats was calculated,and pulmonary function of the rats was detected.The percentage of regulatory T cells was determined,and pathological changes of the lungs was observed by HE staining.Foxp3,TGF-β1,Smad3,Smad7 protein expression in the lungs of the two groups of rats was examined by immunohistochemistry.Results:①Compared with those of the normal,the swelling degree of toes,AI,and the lung index were increased.The average peak expiratory flow in 1 second (FEV1/FVC),alveolitis points,TGF-β1 and Smad3 protein expression was significantly higher in the AA model group rats(P＜0.01).Forced vital capacity (FVC),25% of vital capacity of the peak expiratory flow (FEF25),50% of vital capacity of the peak expiratory flow (FEF50),75% of vital capacity of the peak expiratory flow (FEF75),maximum mid-expiratory flow (MMF),forced maximal expiratory flow (PEF),pulmonary dynamic compliance (Cldyn),the percentage of CD4~+ T cell,CD25~+ T cell,CD4~+ CD25+~ T cell,Foxp3 and Smad7 protein expression was obviously lower in the AA model group rats(P＜0.01).②FEF50,Cldyn and MMF were negative correlated with the swelling degree of toes,pulmonary coefficient and TGF-β1.FEF50,FEF75,MMF and FEV1/FVC were positiyely correlated with the arthritis index,pulmonary coefficient and Foxp3(P＜0.05 or P＜0.01).Conclusion:The decline in lung function in AA rats.Tip-induced may be sustained after the inflammation,and the development of cause inflammation,to chronic inflammatory response leading to lung injury.Simultaneously,the decline in lung function and Foxp3.Smad3,Smad7,TGF-β1 protein expression was associated.Description transcription factor Foxp3 and TGF-β1/Smads signal transducation pathway may participate in the mechanism.
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Objective To evaluate the influences of susceptibility interpretation of Escherichia coli,Klebsiella pneumonia and Proteus mirabilis in China mainland according to the old and new ceftazidime,cefotaxime and ceftriaxone breakpoints in CLSI M100-S20 and CLSI M100-S19. Methods First, We analyzed the antibacterial susceptibility results of the three bacteria by agar dilution method in the SEANIR surveillance item, which were collected from 15 national hospitals between the year of 2005 and 2007 and excluded the AmpC enzyme positive isolates according to the PGR-DNA sequencing method and/or the antibacterial susceptibility phenotype. ESBL phenotype was confirmed by the CLSI phenotypic confirmatory test. Antibacterial susceptibility of the total 2733 Escherichia coli, Klebsiella pneumonia, Proteus mirabilis isolates was retrospectively analyzed by WHONET 5. 4 software according to the breakpoints of the CLSI M100-S19 (S19) and CLSI M100-S20 (S20). Second, 207 isolates of Peking Union Medical College Hospital with the results of both agar dilution method and disk diffusion method were performed by recurrent analysis. Then we observed the inter-method agreement through the scatter diagram according to the breakpoints of S19 and S20. Results First, as to the ESBL positive Escherichia coli, Klebsiella pneumonia and Proteus mirabili.s, the resistant rate of cefotaxime increased from 65.2% , 55.5%, 14. 6% under S19 (64 μg/ml) to 99. 7%, 96. 2% , 93. 8% under S20 (4 μg/ml). The susceptibility rates decreased from 6. 0%, 11.5%, 33.3% under S19 (8 μg/ml) to 0%, 0. 2%, 0% under S20 ( 1 μg/ml). Ceftriaxone had the same trend as cefotaxime. Though ceftazidime was more active than cefotaxime and ceftriaxone, as to the ESBL positive Escherichia coli and Klebsiella pneumonia, the resistant rates slightly increased from 30. 3%,43. 2% under S19 (32 μg/ml) to42.0%, 56. 0% under S20 (16 μg/ml). The susceptibility rates slightly decreased from 58. 1%, 44. 1% under S19 (8 μg/ml) to 44. 7%, 28.0% under S20 (4 μg/ml). Second,as to the ESBL negative Escherichia coli, Klebsiella pneumonia and Proteus mirabilis, all the susceptibility rates of ceftazidime, cefotaxime and ceftriaxone were between 99. 2%-100. 0%, the resistant rate were between 0%-0. 4%. Third, the S20 MIC breakpoints had a good correspondence with the ESBL phenotype.Fourth, according to the recurrent analysis of MIC testing and disk dilution method, r value was 0. 67,0. 79, 0. 77 for ceftazidime, cefotaxime and ceftriaxone, respectively, and all P value were under 0. 01. The intermethod rates of S19 and S20 were both acceptable. Conclusions If the cefotaxime and ceftriaxone S20 new breakpoints were used, the concordance of antibacterial susceptibility results and ESBL phenotype would increase greatly. The clinician could select proper antibiotics according to the antibacterial susceptibility results and clinical symptoms. It is no longer necessary to edit results for cephalosporins, aztreonam, or penicillins from susceptible to resistant. However, until laboratories implement the new interpretive criteria,ESBL testing should be performed as described in Supplemental Table 2A-S1. The relationship between the new breakpoints of ceftazidime and clinical outcomes need to be further evaluated.
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Objective To evaluate the performance of modified Hodge test on the detection of carbapenemases among Enterobacteriaceae with decreased susceptibility to carbapenems. Methods Fortynine Enterobacteriaceae isolates with decreased susceptibility to carbapenems ( MIC of imipenem, meropenem or ertapenem was ≥ 2 μg/ml ) were collected from 16 teaching hospitals from 2004 to 2008. MICs of imipenem, meropenem and etapenem were determined by agar dilution method. Carbapenemases were detected by modified Hodge test. Carbepenemase-causing positive results and AmpCs-causing positive results were differentiated by phenyl boronic acid and oxacillin. Beta-lactamases encoding genes including blaNDM-1were detected by PCR and sequencing. Results Thirty-six of 49 isolates were non-susceptible to imipenem (MIC >4 μg/ml), 31 were non-susceptible to meropenem (MIC > 4 μg/ml) and 47 were non-susceptible to ertapenem (MIC > 2 μg/ml). Twenty-three isolates showed positive modified Hodge test result, including 9 weak-positive results and 14 strong-positive results. Through PCR detection and sequencing, 2 out of 9 isolates showing weak-positive results carried blaKPC-2 and other 7 did not carry any carbapenemase genes but AmpCs/ESBLs genes. Among the 14 isolates showing strong-positive results, 4 carried blaKPC-2, 8 carried blaIMP-4 and 2 caried blaIMP-8. All 26 isolates with negative modified Hodge test result didn't carry any carbapenemase genes. No isolate carried blaNDM-1. Carbapenemases genes PCR detection was regarded as a gold standard, and the sensitivity, specificity, positive predictive value and negative predictive value of modified hodge test was 100%, 79%, 70% and 100% on the detection of carbapenemases among Enterobacteriaceae with decreased susceptibility to carbapenems. Conclusions Modified Hodge test revealed great sensitivity but showed a few false positive results. True and false positive results can be effectively differentiated by phynel boronic acid and oxacillin.
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Objective To compare the in vitro activity of cefminox with other antimicrobial agents against clinical Escherichia coil, Klebsiella pneumoniae isolates and Bacteroides species. Methods MICs of sixteen antimicrobial agents against 945 Escherichia coli and 588 Klebsiella pneumoniae isolates from 15 teaching hospitals and MICs of four antimicrobial agents against 50 Bacteroides species isolates were determined by agar dilution method. WHONET 5.4 software was used to analyze the data. Results Among 1533 Escherichia coli and Klebsiella pneumoniae isolates, 628 isolates produced neither extended-spectrum beta-lactamases (ESBLs) nor AmpC, while 837 isolates produced only ESBLs and 68 isolates produced AmpC enzymes. The susceptibility rate of cefminox against non-ESBLs-producing or ESBLs-producing isolates was above 90%. MIC_(50) of eefminox was 2-4 fold lower than cefometazole and 8-16 fold lower than cefoxitin. MIC50 of cefminox was 2-8 fold lower than cefometazole and 8-16 fold lower than cefoxitin. Against ESBLs-producing isolates, the in vitro activity of cefminox was superior to the third and fourth generation cephalosporins, aztreonam, cefoperazone/sulbactam, levofloxacin, amikacin and inferior to carbapenems. Its activity was similar to piperacillin-tazobactam. The susceptibility rate of cefminox against AmpC-producing isolates was less than 20%. The susceptibility rate of cefminox against Bacteroides species was 90%, which was higher than that of cefometazole (50% -70%) and penicillin (0%) and similar to that of metronidazole. Conclusion Cefminox exhibites good activity against ESBLs-producing and non-ESBLs-producing Escherichia coli and Klebsiella pneumoniae isolates and Bacteroides species, which indicates that cefminox could be one of the options for the treatment of infections caused by these organisms.
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Objective To evaluate the in vitro activity of daptomycin, vancomycin, teicoplanin, tigecycline, ceftobiprole and linezolid against 499 strains of blood-isolated gram-positive cocci. Methods Determination of the minimal inhibitory concentration (MICs) of daptomycin with microbrothdilution method and the MICs of other 9 antimicrnhial agents with agar dilution method against 499 strains of blood-isolated gram positive cocci was carried out. The data was analyzed with WHONET 5.4 software. Results The susceptibility rates of staphylococci to daptomycin, tigecycline, linezolid, ceftobiprole, vancomyein and teicoplanin were 100%. All staphylococcus strains were inhibited by daptomycin at a MIC of 1 mg/L. The MIC50 and MIC60 of daptomyein were both 0.5 mg/L against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus coagalase-negative (MRSCnN). Among Enterococcus spp, the highest MIC of daptomycin was 4 mg/L. The MIC50 and MIC90 of daptomycin were both 2 mg/L against E.faecalis, whereas they were 2 mg/L and 4 mg/L against E.faecium. One strains of linezolid-resistant E.faecalis(MIC:8 mg/L)was susceptible to daptomycin (MIC: 1 mg/L). Three strains of E.faecium carrying vanA gene with vancomycin MICs above 32 mg/L and teicoplanin MICs also 32 mg/L were susceptible to daptomycin, tigeeycline and linezolid. The MIC range of daptomycin against Streptococcus pneumoniae and Streptococcus viridans was 0.032-0.25 mg/L and 0.125-1.000 mg/L separately. Conclusions Daptomycin has excellent in vitro activity against common gram-positive pathogens isolated from blood. It may be a good choice for clinicians to treat drug-resistant gram-positive cocci.
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Objective To establish the real-time quantitative PCR (RQ-PCR) assay for detecting Candida albicans (C.albicans) in whole blood and its clinical application in the febrile surgical patients who may develop gut barrier damage and gut microorganism translocation.Methods The NAG1 gene,which is a single copy in C.albicans genome,was selected as the target gene for designing the primers and probe.The plasmid was fabricated and produced as standard samples.C.albicans genomes were extracted with QIAamp(R) DNA Blood Mini Kit,and the total 20 μl TaqMan RQ-PCR amplification reaction system was established.The 74 venous blood samples from the surgical febrile patients were detected for C.albicans load.Results The specificities of the primers and probe were excellent,the correlation coefficients of the standard curves were between 0.9918 and 0.9985,and the efficiency of amplification was 0.88-1.027 for the samples above the lowest detection limit (100 copies/μl examine fluid,or nearly 1.1 × 103 cfu/ml whole blood).The average accuracy of the RQ-PCR equipment was (99.64±2.08) %,the sensitivity was 97.46%,the specificity was 100%,and the average coefficients of variation (CV) of the intra-and inter-assay were (14.76±2.64)% and (17.85±3.53)%,respectively.The average recovery rate of C.albicans DNA in whole blood samples was (88.60±5.73) %,and the average CV of recovery rate was (11.70 ±5.36) %.The number of copies of C.albicans genes per unit blood was not significantly different among the same original blood samples stored separately under-20℃ for 3 or 6 months when compared with its freshly collected blood (P = 0.267).In the 74 whole blood samples obtained from the febrile surgical patients,the positive rate of C.albicans genes was 2.7% and the highest load was 4.42×103 cfu/ml.Conclusions RQ-PCR is a rapid,sensitive,highly specific,and reproducible method in detecting C.albicans NAG1 gene.Clinically it can be used to quantitatively evaluate the numbers of C.albicans in the whole blood.A small percentage of the febrile surgical patients may develop blood infection of C.albicans.
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Objective To investigate antimicrobial resistance among nosocomial gram-negative bacilli in 2006.Methods About 987 consecutive and non-repetitive gram-negative bacilli were isolated from 10 teaching hospitals from Sep.to Dec.in 2006 in China.All of these isolates were sent to the central laboratory for reidentification and susceptibility testing.The minimal inhibitory concentration(MICs)of meropenem and other antibacterial agents were determined by agar dilution method.Results The activity of antibacterial agents against Enterobacteriaceae was as fol lows in descending order of susceptible rate: meropenem(susceptible rate 99.8%),imipenem(99.5%),piperacillin/tazobactam(91.3%),amikacin (89.3%),cefepime(83.8%),cefoperazone/sulbactam(79.7%),ceftazidime(74.7%),cefotaxime (57.7%),ceftriaxone(56.6%),ciprofloxacin(53.6%).The prevalence of extended-spectrum β-Iactamases(ESBL)was 59.0% in Escherichia coli,33.0%in Klebsiella pneumoniae and 8.0%in Proteus mirabilis.The most active agents against E.coli and K.pneumoniae were meropenem,imipenem(99.2%. 100%),piperacillin/tazobactam(90.8%-97.0%),and amikacin(83.8%-92.4%).Cefepime Was more active against K.pneumoniae than E.coli(85.4% vs.65.2%).Against E.cloacae,E.aerogenes and Citrobacter freundii,the most active agents were as follows in desecnding order:meropenem,imipenem (99.2%-100%),amikacin(85.2%-92.6%),cefepime(81.5%-85.9%),piperacillin/tazobactam (73.4%-87.2%),cefoperazone/sutbactam(65.6%-77.7%),and ciprofloxacin(53.1%-72.3%).The most active agents against Pseudomonas aeruginosa were amikacin(83.5%),followed by meropenem (79.1%),piperacillin/tazobactam(74.1%),and imipenem(70.9%).The most susceptible agents against Acinetobacter baumannii were imipenem(79.1%),meropenem(73.4%) and cefoperazone/ sulbaetam(54.7%).Mutiresistant A.baumannii increased up to 53.0%.The most active agents against Burkholderia cepacia were meropenem(73.3%),eeflazidime(73.3%),and piperacillin/tazobactam (62.2%).Conclusions Carbapenems remained very high activity against Enterobacteriaceae.Increasing resistance to 10 antimicrobials agents tested from A.baumanni and P.aeruginosa brought great concern.
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Objective To investigate antimicrobial resistance among gram-positive cocci in China in 2006.Methods From Jun 2006 to Dec 2006,674 consecutive and non-repetitive gram-positive bacteria were collected from 7 teaching hospitals.The minimal inhibitory concentration(MICs)of antibacterial agents were determined by agar dilution method.Results The prevalence of penicillin.resistant(ease)and pemcllhn. intermediate S.pneumoniae(PISP)among 100 isolates was l%and 19%,respectively.Teicoplanin and vancomycin were the most active agents against S.pneumoniae.97% and 98% S.pneumoniae isolates were susceptible to levofloxacin and moxifloxacin,respectively.The susceptibility of amoxicillin/clavulanic acid, ceftriaxone and chloramphenicol are 96%,87% and 73%,respectively.The susceptible rates of penicillin. susceptible S.pneumoniae(PSSP)to cefprozil and cefaclor were 62% and 55.7%,respectively.All the PISP and PRSP isolates were resistance to the two antibiotics.The susceptibility to macrolides,trimethoprim/ sulfamethoxazole and tetracycline was lower than 35%.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA)and methicillin.resistant coagulase-negative Staphylococci(MRSCON)was 48%(33%-84%)and 81%(69%-94%),respectively.The susceptible rates of MRSA to trimethoprim/ sulfamethoxazole,chloramphenicol,rifampin,and the other antibiotics in this study were 72%,66%and 45%,respectively.The susceptible rate of MRSA to marcrolides,aminoglycosides,tetracyclines and quinolones were not more than 18%.56%(30%-86%)of E.faecalis and 80%(50%.100%)of E.faecium were highly resistant to gentamicin.The susceptibility of E.faecalis to all the antibiotics except chloramphenicol and tetracycline were higher than E.faecium.All isolates of S.aureus,CoNS and E.faecalis tested were susceptible to vacomycin and teicoplanin.There were two vacomycin.resistant E.faecium strains isolated from Hangzhou.Conclusions Antimicrobial resistance patterns of gram.positive cocci differed in different regions.The resistance of gram-positive cocci to the antibiotics in this study this year was a little higher than the data of the year of 2005.Teicoplanin and vancomycin remained very high activity to gram-positive cocci.
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OBJECTIVE To investigate the antimicrobial resistance of hospital-and community-acquired pathogens collected from 10 teaching hospitals located at different areas in China in 2006.METHODS According to the study protocol,the strains of Streptococcus pneumoniae,meticillin-susceptible Staphylococcus aureus(MSSA),Escherichia coli and Klebsiella pneumoniae were collected and sent to the central lab for reidentification and susceptibility testing.The minimal inhibitory concentrations(MICs) of antimicrobial agents against Str.pneumoniae were determined by Etest method and MICs of antimicrobial agents against S.aureus,E.coli and K.pneumoniae strains were determined by agar dilution method.WHONET5.4 software was used to analyze the data.RESULTS Among 353 Str.pneumoniae strains,74.2% were penicillin-susceptible(PSSP),9.6% were penicillin-intermediate(PISP) and 16.2% were penicillin-resistant(PRSP).Strains from different hospitals showed different sensitivity to penicillin.Among ?-lactam antibiotics,cefuroxime showed the lowest susceptibility rate of 0%(for PRSP) to 76.7%(for PSSP).The susceptibility rate to ceftriaxone and amoxicillin-clavulanic acid was 98.1% and 98.9% in PSSP group,61.8% and 64.7% in PISP group,and 15.8% and 10.5% in PRSP group.The ESBLs rate was 56.2% among 267 Escherichia strains and 42.7% among 206 K.pneumoniae strains.For ESBLs-producing strains,the susceptibility rates to cefotaxime and ceftriaxone were low and the rate to ceftazidime was relatively high among ?-lactam antibiotics.73.4% MSSA strains produced ?-lactamase.?-Lactam antibiotics tested showed high susceptibility against MSSA strains.The susceptibility rate was 98.9-100%.The susceptibility rate to ciprofloxacin and levofloxacin was 80.8% and 88.1%,separately.CONCLUSIONS Fluoroquinolones show high susceptibility against Str.pneumoniae.Ceftriaxone and amoxicillin-clavulanic acid have relatively high susceptibility among ?-lactams.For MSSA and non-ESBLs-producing E.coli and K.pneumoniae strains,?-lactams show high susceptibility.For ESBLs-producing E.coli and K.pneumoniae strains,the susceptibility rates to cefotaxime and ceftriaxone are low and that to ceftazidime,cefepime and cefoperazone-sulbactam are relatively high.
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OBJECTIVE To investigate predisposing factors of candidemia in nosocomial infections.METHODS To retrospectively review the clinical features of 120 cases,including 59 who developed candidemia and 61 cases with bacteremia during the period of 1990-2004.RESULTS The incidence of candidemia was stable over a 14-year period.Candida albicans remained the predominant Candida species recovered(30.5%),followed by C.tropicalis(25.7%),C.glabrata(12.9%),C.parapsilosis(12.9%) and others(17.1%).Of the total 59 cases of candidemia,were administrated by broad spectrum antibiotic therapy for long time,urinary catheters,malignant tumor,etc.Multivariate analysis showed that candidemia was related with many factors.CONCLUSIONS C.albicans was the major pathogen in our hospital during 14 years;the candidemia is related with the use of quinolones,ventilator,central venous catheters and radiation-chemotherapy(P
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80% activity rate against E.coli included piperacillin/tazobactam(93.4%)、ceftazidime(86%),and amikacin(83.3%);The susceptible rate to piperacillin/tazobactam in K.pneumoniae was 84.6%. The susceptible rate to ceftazidime decreased from 82.3% to 69.9%, which was lower than to cefepime (77.2%). Over 50% of Enterobacter cloacae were resistant to ceftazidime, cefotaxime and ceftriaxone. Susceptible rates to piperacillin/tazobactam in E. cloacae,E. aerogenes,Citrobacter freundii and Serratia marcescens (67.7%-96.4%) were higher than those to cefepime (68.8%-77.5%), cefoperazone/sulbactam (59.7%-87.5%). Susceptibility to amikacin among these 4 species (70%-83.7%) was higher than to ciprofloxacin (48.1%-79.5%). All of Morganella morganii and Proteus vulgaris isolates were susceptible to meropenem and imipenem; Over 90% of the isolates were susceptible to cefepime, cefoperazone/sulbactam and piperacillin/tazobactam.The most active agent against Pseudomonas aeruginosa was meropenem (84%), followed by amikacin, piperacillin/tazobactam, ceftazidime and imipenem (72.5%-76.6%). Mutiple-drug-resistant Acinetobacter baumannii increased from 33% in 2003 to 48% in 2004. Resistance to carbapenems increased to 18% in this species in 2004. The most active agents against Burkholderia cepacia were meropenme (64.9%), cefoperazon/sulbactam (63.2%), ceftazidime (59.6%), piperacillin/tazobactam (56.1%) and cefepime (52.6%).Conclusions Carbapenems remained very high activity against Enterobacteriaceae. Increasing resistance to 10 antimicrobials agents tested among A. baumanni brought great concern. Meropenem was 4-to 16-fold more active against common gram-negative bacilli than imipenem.