1.Analysis of distribution and drug resistance of pathogenic bacteria in burn wards
Zhengpeng XU ; Su WANG ; Lizhong HAN ; Wenkui WANG
Journal of Shanghai Jiaotong University(Medical Science) 2017;37(4):527-531
Objective·To analyze changes in the type distribution and drug resistance of pathogenic bacteria isolated from burn wards and to provide evidence for rational use of antibiotics, reduction of drug-resistant isolates, and hospital infection control. Methods·Isolates from burn patients were collected from January 2011 to December 2014. Statistical analysis of infection sources, type distribution, and changes in resistance rates of main pathogens during the four year period was performed. Results·A total of 2399 isolates were collected, including 1286 (53.61%) gram-negative bacilli (G-b), 1088 (45.35%) gram-positive cocci (G+c), and 25 (1.04%) fungi. The most common G-b pathogens were Pseudomonas aeruginosa (447, 34.76%) and Acinetobacter baumannii (369, 28.69%). The most common G+c pathogen and fungus were Staphylococcus aureus (489, 44.94%) and Candida albicans (8, 33.33%), respectively. In the last two years, the detection rates of S.aureus and A.baumannii were significantly lower and the detection rate of P.aeruginosa was significantly higher than those in the first two years (P<0.05). P.aeruginosa and A.baumannii showed high resistance (>80%) to the third and fourth generation cephalosporins, carbapenems, aminoglycosides and quinolones, but the changes were not statistically significant (P>0.05). S.aureus was only highly resistant to penicillin (97.58%) and was 100% susceptible to vancomycin. Its resistance rates toward cefazolin, ampicillin/sulbactam, gentamicin, levofloxacin, and rifampin decreased significantly (P<0.05). The detection rate of methicillin-resistant S. aureus (MRSA) dropped from 72.28% to 63.00%. Conclusion·Many types of drug resistant bacteria were detected in burn wards. The drug resistance problem was serious. Improving management and rational use of antibiotics can reduce the occurrence of drug-resistant bacteria and increase the efficacy of clinical anti-infective treatment and nosocomial infection control.
2.Construction and identification of recombinant adenovirus vectors carrying the human transcription factor PU.1 gene
Chenyang LIU ; Wenjie YAN ; Min WANG ; Wenkui SUN ; Xin SU ; Yi SHI
Journal of Medical Postgraduates 2016;29(5):465-469
Objective PU.1 plays a key role in innate immune function in the alveolar macrophage.This study was to con-struct and identify recombinant adenovirus vectors carrying the human transcription factor PU.1 gene. Methods The recombinant shut-tle plasmid was obtained from the PU.1 gene ( SPI1) and eukaryotic expression vector that digested by restriction enzymes and connected by T4 DNA ligase.The target fragment SPI1-IRES-EGFP was amplified by PCR.The product was cloned into the intermediate pDONR221 and then recombined with the adenovirus backbone plasmid pAd/CMV/V5-DEST to form a recombinant adenovirus vector. The recombinant adenovirus vector was linearized by PacI and then transfected into human embryonic kidney (HEK293) cells to obtain the recombinant adenovirus pAD-SPI1-IRES-EGFP, which was then propagated in HEK293 cells, filtered and purified to obtain high-con-centration adenoviruses.The adenovirus titer was determined by TCID 50 assay.The PU.1 gene expression in the HEK293 cells was con-firmed by fluorescence microscopy and real-time qPCR. Results PCR amplification, restriction digestion and sequencing analysis showed the recombinant adenovirus carried the correct PU.1 gene.The final virus titer, calculated by TCID 50, was 8 ×1011 IU/mL. Green fluorescence was observed under the fluorescence microscope. Real-time qPCR confirmed that the expression of PU.1 mRNA was increased by 2189.93 folds. Conclusion The recombinant adenovirus vector carrying the PU.1 gene was constructed and obtained successfully, which could contribute to further studies of the influence of PU.1 overex-pression on the innate defense against Aspergillus fumigatus.
3.Construction and identification of a recombinant adenoviral vector expressing murine dendritic cell-associ-atedC-type lectin-1
Di XIA ; Qian QIAN ; Zhicheng LIU ; Mingming TAN ; Yuan DING ; Xin SU ; Wenkui SUN ; Yi SHI
Journal of Medical Postgraduates 2015;(4):341-345
Objective Dendritic cell-associatedC-type lectin-1 ( Dectin-1) is one of the most important receptors in antifungal innate immune response.This study was to construct a recombinant adenovirus vector expressing themurine Dectin-1gene and acquire a high-concentration adenovirus by amplification and purification. Methods The PCR amplification product CLEC7A-pIRES2-EGFP was cloned into the intermediate vector pDONR221, and then recom-bined with the backbone vector pAD/CMV/V5-DEST to produce a re-combinant plasmid pAD-CLEC7A-pIRE2S -EGFP.The recombinant plasmid was linearized with Pac I and transfected into human embryon-ic kidney ( HEK293) cells to produce recombinant adenovirus pAD-CLEC7Ap-IRES 2-EGFP. The adenovirus was propagated in the HEK293 cells and purified by filtering through the cellulose acetate membrane and concentrating column.Fluorescence microscopy and re-al-time PCR were used to determine the expression of the Dectin-1 gene. Results PCR identification, enzyme digestion, and sequen-cing results manifested theDectin-1 gene in the vector, with the final adenovirus titer of 5×1011 IU/mL.Fluorescence microscopy revealed green fluorescence and real-time PCR assay confirmed that the expression of Dectin-1 was improved by 8677.25 times. Conclusion A relatively high-titer adenovirus expressing Dectin-1 was acquired,which may help to further study the high expression of Dectin-1 in anti-fungal innate immunity in vitro and in vivo.
4.Comparison of susceptibility testing by EUCAST and CLSI broth microdilution methods against Aspergillus isolates
Fei CHEN ; Wenkui SUN ; Ting WU ; Wenjie YAN ; Xin SU ; Yi SHI
Chinese Journal of Infection and Chemotherapy 2014;(4):338-343
Objective To compare the results of susceptibility testing by European Committee on Antimicrobial Susceptibility Testing (EUCAST)and Clinical and Laboratory Standards Institute (CLSI)broth microdilution methods against Aspergillus isolates.Methods The susceptibilities of 116 Aspergillus isolates were determined for amphotericin B, voriconazole, itraconazole,caspofungin and micafungin according to EUCAST (E.DEF 9.1 )and CLSI (M38-A2)methods.The essential agreement (EA),categorical agreement (CA),very major errors (VME)and major errors (ME)of the two methods were compared.Results The EA was 96.3%-100% between the two methods.The CA ,ME,and VME were 98.8%,0-1.2% and 0 respectively for the susceptibility of Aspergillus fumigatus to voriconazole.The CA,ME and VME was 1 00%,0 and 0 respectively for the susceptibility of Aspergillus fumigatus and Aspergillus niger to amphotericin B,or the susceptibility of Aspergillus fumigatus and Aspergillus flavus to itraconazole.Conclusions The results of susceptibility testing by EUCAST and CLSI broth microdilution methods are well consistent against Aspergillus isolates.
5.Application and overview of image guided surgery system.
Wenkui SU ; Yuli ZHANG ; Dongmei LI ; Zhaoying ZHOU
Chinese Journal of Medical Instrumentation 2010;34(4):284-288
This paper introduces the development and the key technology of image guided Surgery Systems (IGSS) and analyses its prospect in this paper. IGSS can be used in clinical surgery as an assistant tool, and it would be an advanced medical equipment combined with medical robotics.
Robotics
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Surgery, Computer-Assisted
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instrumentation
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methods