1.Molecular epidemiological survey of highly multigrug-resistant Pseudomonas aeruginosa
Chinese Journal of Laboratory Medicine 2001;0(03):-
Objective To verify if the multidrug resistant stains of P.aeruginosa isolated from different patients in burn ward have the same origin. Methods The susceptibility testing was performed with Etest,and the strains were typed by rep PCR with the primer ERIC2 and M13 following electrophoresis in agarose gel. Results There were multidrug resistant P.aeruginosa strains in burn ward,and analysis of the PCR productions indicated that all these multidrug resistant strains have an identical band pattern different from the sensitive strains. Conclusions The multidrug resistant strains of P. aeruginosa derive from a common origin.
2.Surveillance of Bacterial Resistance in Hematology Ward
Chinese Journal of Nosocomiology 2006;0(02):-
OBJECTIVE To investigate the epidemic characteristics and drug resistance profile of clinical bacteria in hematology ward of our hospital. METHODS The susceptibility testing of clinical isolates from hematology ward was performed and the ESBLs producing strains were detected using K-B method.The results were analyzed by WHONET5. RESULTS Out of the 397 clinical isolates, 65.2% were Gram-negative bacilli and 34.8% were Gram-positive cocci.In Gram-negative bacilli,55% were Enterobacteriaceae and 44% were nonfermenting Gram-negative bacilli.In Gram-positive cocci,60.8% were Staphylococcus spp and 38.4% were Enterococcus spp.The ESBLs producing strains in Escherichia coli and Klebsiella spp were 55.8% and 19.2%,respectively.The MRSA in S.aureus and MRCNS in coagulase negative Staphylococcus were 40.9% and 95.2%,respectively.No resistance to carbapenem was detected in Enterobacteriaceae and no resistance to vancomycin was detected in Gram-positive cocci.The resistance rate of nonfermenting Gram-negative bacilli to cefoperazone/sulbactam was less than 2.1%. CONCLUSIONS The data will be useful for the early empiric administration of antimicrobial agent in hematology ward.
3.Effect of Delayed Entry into 2 Different Blood Culture Systems(BacT/Alert 3D and BACTEC 9120) on Culture Positivity
Jingyong SUN ; Min ZHOU ; Yuxing NI
Chinese Journal of Nosocomiology 2009;0(16):-
OBJECTIVE To evaluate the effect of delayed entry(0-24 h) into BacT/Alert 3D and BACTEC 9120 and the effect of 2 incubation temperatures(22 ℃ vs 35 ℃) on culture positivity.METHODS We utilized the BacT/Alert system with FA bottles and the BACTEC 9120 system with Plus(Aerobic) bottles.Four clinical bacterial species,Staphylococcus aureus,Escherichia coli,Streptococus pneumoniae,Candida albicans,were used as the test strains.and 5 ml of blood were added to each bottle.Each species was inoculated into the bottles 3 times at an inoculum size of 10 CFU/ml,102 CFU/ml and 108 CFU/ml,respectively.The inoculated bottles were cultured using the respective instruments after they were allowed to stand at room temperature(22 ℃)and 35 ℃ for 0,8,16 and 24 h.Time-to-detection and culture positivity were evaluated.RESULTS The delay in transportation of blood culture bottles stored at room temperature(22 ℃) or 35 ℃ had no effect on the recovery rate for BACTEC 3D at less than 24 h preincubation time and for BacT/Alert 9120 at less than 16h preincubation time.The positivity rate decreased significantly for BacT/Alert 9120 for 24 h of delay.Culture positivity of BacT/Alert 3D was higher than BACTEC 9120 for 24 h of delay.CONCLUSIONS The delayed entry for BacT/Alert 3D should be within 24 h,but the delayed entry for BACTEC 9120 should be within 16 h.
4.Distribution and antimicrobial resistance of pathogenic bacteria causing urinary tract infection
Ya LI ; Wen ZHANG ; Jingyong SUN ; Yuxing NI ; Nan CHEN
Chinese Journal of Nephrology 2010;26(5):325-329
Objective To analyze the distribution and antimicrobial resistance of pathogenic bacteria in urinary tract infection (UTI)so as to provide evidence for appropriate selection of antimicrobial agents in clinical practice. Methods From January 2001 to December 2008 in Shanghai Ruijin Hospital,4683 strains of pathogenic bacteria isolated from urine samples were detected by ATB system;drug susceptibility test was performed with disk diffusion method and pathogenic bacteria distribution and drug resistance was analyzed with WHO NET 5.3 software. Results Among 4683 strains of pathogenic bacteria,most was gramnegative bacilli,accounting for about 77.8%,of which predominant strain was Escherichia coli (68.7%,3217/4683).The predominant strain of gram-positive bacteria was Enterococcus faecalis,accounting for 10.0%(468/4683).Escherichia coli showed hish resistance rotes to ampicillin,piperacillin and compound snlfamethoxazole(SMZ-TMP),which were 76.6%,61.7%and 57.4%respectively,while a low resistance to imipenem,cefoperazone-sulbactam,piperacillin-tazobactam,Enterococcus faecalis showed high resistance rates to erythromycin,gentamicin and levofloxacin,which were 65.8%,43.2%and 31.1%respectively,and were most susceptive to vancomycin and teicoplanin, both with resistance rates of 0. The susceptibility rate of Enterobacteriaceae to imipenem was 100%. From 2006 to 2008, the detection rate of extend-spectrum β-lactamases ESBLs -producing Escherichia coil in outpatient increased year by year, from 28.7% to 43.3% (P<0.05), whereas no significant change was found in inpatients. The detection rate of (ESBLs)-producing Escherichia coil in inpatients was significantly higher than that in outpatients (P<0.05).The detection rate of ESBLs-producing Escherichia coil was 23.6%. The antimicrobial resistance rate in elderly patients was significantly higher than that in overall antimicrobial resistance rote (P<0.05). Conclusions The predominant bacteria of UTI are still gram-negative bacteria, main of which is Escherichia col. Bacteria are resistant to a variety of antibiotics. Approximate selection of antibiotics in clinical practice should be made on the basis of susceptibility test results.
6.Prevalence and genotypes of carbapenemase-producing Enterobacteriaceae
Fangfang ZHANG ; Xiaoli WANG ; Hongping QU ; Yuxing NI ; Jingyong SUN
Chinese Journal of Infection and Chemotherapy 2014;(6):521-525
Objective To investigate the prevalence and main genotypes of carbapenemases in carbepenem‐resistant Enterobacteriaceae (CRE) .Methods A total of 114 strains of CRE were isolated in Shanghai Ruijin Hospital from May 2011 to June 2013 .The diameter of inhibition zone of imipemen or meropenem for these strains was not larger than 22 mm .PCR method was used to screen for the main carbapenemase genes (blaKPC ,blaIMP ,blaVIM ,blaOXA‐48 and blaNDM ) with previously described primers followed by nucleotide sequencing analysis . Conjugation experiments were performed to examine the transferability of plasmids .Pulsed‐field gel electrophoresis (PFGE) was used to show the relatedness of KPC‐2‐producing Enterobacteriaceae .Results Most of the 114 isolates were K lebsiella pneumoniae and Escherichia coli .Of the 114 isolates ,98 was positive for carbapenemases ,specifically ,78 blaKPC‐2‐positive ,15 blaIMP‐4‐positive ,2 blaIMP‐8‐positive ,1 positive for both blaKPC‐2 and blaIMP‐4 and 4 blaNDM‐1‐positive .None of the strains was positive for blaOXA‐48 or blaVIM .About 21 .4% (21/98) of the isolates were conjugated successfully .The 49 blaKPC‐2‐positive K .pneumoniae isolates were grouped into 12 types according to PFGE patterns .Majority (34/49) of these isolates belonged to the same type A .Conclusions BlaKPC‐2 was the primary epidemic genotype of Enterobacteriaceae in Ruijin Hospital ,followed by blaIMP‐4 .NDM‐1 carbapenemase was produced in 4 strains of CRE . Meanwhile , clonal spread of KPC‐2‐producing K . pneumoniae was observed in some departments of our hospital , such as surgical ICU , respiratory medicine and thoracic surgery . Appropriate measures should be taken timely and effectively to prevent the in‐hospital spread of resistant genes .
7.Pharmacological Studies on Liniao Capsules
Yuxing CHEN ; Ruiling ZHOU ; Lan SUN ; Jingchao CUI ;
Chinese Traditional Patent Medicine 1992;0(02):-
Objective:To observe the diuretic action of Liniao Capsules (LC). Methods: The urinary effects of LC were studied in the loading rats with water.Results: LC could significantly increase the urinary output, shorten the latent period of emiction, and reduce the contents of TP in urine and BUN in blood serum. Conclusion: LC exerted the significant diuretic effect in rats.
8.Levels of Interleukin-4, Interleukin-6 and Interferon-gamma in Bronchoalveolar Lavaga Fluid of Children with Refractory Mycoplasma Pneumoniae Pneumonia and the Features of Bronchoscopy
Li TAN ; Chengqing WU ; Yuxing SUN ; Zhengyan GAN
Journal of Kunming Medical University 2016;37(7):70-73
Objective To explore the interleukin-4 (IL-4),interleukin-6 (IL-6),interferon-gamma (IFN-γ) levels in bronchoalveolar lavage fluid (BALF) of children with refractory mycoplasma pneumoniae pneumonia,and the features of bronchoscopy.Methods A total of 47 children with refractory mycoplasma pneumoniae pneumonia were selected as the observation group,28 children with bronchial foreign body in GAN zhengyan were chosen as controls during the same period.ELISA method was used to detect the IL-4,IL-6,IFN-γ levels in the BALF,and compared them in these two groups.The bronchoscope features of the observation group were observed.Results The IL-4,IL-6,IFN-γ levels in the BALF of children in the observation group were (8.3 ± 3.1) pg/mL,(62.3 ± 18.4) pg/mL,(76.5 ± 21.9) pg/mL,and they were significantly higher than those of the controls (3.1 ± 1.2) pg/m L,(30.0 ± 1.5) pg/m L,(31.3 ± 24.9) pg/mL (P <0.05,respectively).In the observation group,the bronchial mucosa congestion and edema were observed in all patients,there were variable amounts of mucus secretions.There were other changes include:microtubule reductus (68.1%),bronchial mucosal follicle-like hyperplasia (38.3%),mucosal erosions (8.5%),airway inflammatory stenosis,mucus plug blocking (59.6%),granulation proliferation (14.9%),bronchial obliteration (4.3%) Conclusions The IL-4,IL-6,IFN-γ levels in the BALF of children with RMPP significantly increased.This indicates a significant local inflammatory response in children with RMPP.Mycoplasma pneumoniae pneumonia (MPP) has certain features of bronchoscope,these features are helpful to the diagnosis and treatment of MPP.
9.The epidemiological study of methicillin-resistant Staphylococcus aureus in Shanghai
Yibo ZHANG ; Lizhong HAN ; Haiqing CHU ; Yanqun JIANG ; Yang SUN ; Hong ZHANG ; Yuxing NI
Chinese Journal of Laboratory Medicine 2009;32(7):805-809
Objective To investigate antibiotic resistance and molecular epidemiology profile of methicillin-resistant Staphylococcus aureus (MRSA) in Shanghai. Methods The antibiograms of 140 MRSA isolates from 5 hospitals for 13 drugs were analyzed by agar dilution and broth dilution. The PVL gene and SCCmec were detected by PCR; The clonal relatedness of 140 isolates were determined by PFGE and 39 strains were chosen to be characterized further by spa typing. Results All 140 MRSA are PVL negative and most of them were identified as SCCmec Ⅲ [45.7% (64/140)], followed by SCCmec Ⅲ a [25.0% (35/140)], SCCmecⅢb [14.3% (20/140)], SCCmecⅡ [10.7% (15/140)] and SCCmecⅣ [4.3% (6/140)]. All isolates were susceptible to vancomycin, teicoplanin and daptomycin. The resistance to gentamicin, sulphamethoxazole and clindamycin was 98. 6% (138/140), 98. 6% (137/140) and 97. 9% (137/140), respectively. Resistance to erythromycin, ciprofloxacin and tetracycline was above 80%, and resistance to rifampicin was 10. 7% (15/140). Sixteen different PFGE patterns(A-P) were found and most of MRSA belonged to group C[30. 7% (43/140)] ,B[13.6% (19/140)]and Ⅰ [10. 7% (15/140)]. Among 39 strains with prevalent PFGE patterns, 4 spa genotypes were identified: t002133. 33% (13/39)] ,t030 [12. 82% (5/39)] ,t037[51.28% (20/39)]and t459[2. 57% (1/39)]. Conclusions Sixteen different PFGE patterns and 4 spa genotypos were found from 5 hospitals in Shanghai. The most popular MRSA clone is PVL negative, SCCmec Ⅲ, with resistant profile of erythromycin, ciprofloxacin,clindamycin,etracycline, gentamicin,and sulphamethoxazole [E-C-L-T-G-M-]. This result suggests that hospital infection control and reasonable antibiotic usage are critical.
10.Co-production of carbapenem-hydrolyzing enzyme KPC-2 and ArmA 16S rRNA methylase in pandrugs resistant Enterobacter cloacae
Qiong WU ; Yuxing NI ; Lizhong HAN ; Jingyong SUN ; Qingzhong LIU ; Yanqun JIANG ; Feng GAO
Chinese Journal of Microbiology and Immunology 2011;31(10):888-892
Objective To investigate the production of carbapenemase and 16S rRNA methylase in five isolates of pan-drugs resistant E.cloacae recovered in Ruijin hospital.Methods MICs of the five isolates to 10 antibiotics were determined by E test.Six kinds of 16S rRNA methylase genes and a series of β- lactamase genes were amplified by PCR.Shotgun cloning was performed to detect carbapenem resistance determinant.The conjugal transfer of carbapenemase gene and 16S rRNA methylase gene was performed in broth culture with E.coli J53 as the recipient.Pulsed-field gel electrophoresis (PFGE) was carried out to analyse the genotyping.IEF was performed to detect β-1actamases.Southern blot was performed to determine the location of carbapenem resistance determinant.Results The MICs of 10 antibiotics were >32 mg/L.Four β-1actamases with pIs of 5.4 ( TEM-1 ),6.7 ( KPC-2 ),8.2 ( SHV-12 ),8.4 (CTX-M-14) were determined.The insertion sequence in the recombinant plasmid was blaKPC-2 flanked by a transposon.blaKPC-2 was located on a large non-conjugative plasmid whereas armA was located on an other conjugative plasmid.PFGE patterns of 5 isolates were identical.Conclusion KPC-2 was responsible for carbapenem resistance in pandrugs resistant Enterobacter cloacae.There was no relationship between blaKPC-2 and armA.Although pandrug resistant Enterobacteriaceae remain rare,the emergence of this group of organism merits monitoring.