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Objective To evaluate the feasibility of using matrix-assisted laser desorption/ioniza-tion time-of-flight mass spectrometry(MALDI-TOF MS) in combination with Sepsityper Kit or serum-separa-ting gel tubes for identification of pathogenic organisms positive for blood culture. Methods A total of 153 clinical specimens with a positive result in blood culture were collected and tested with MALDI-TOF MS in combination with Sepsityper Kit or serum-separating gel tubes. Test results were compared with those by using culturing. Results The 153 positive blood culture specimens included 143 of single bacterial infection and 10 of multiple bacterial infections. The consistency rates at species and genus levels were 76.2% (109/153) and 7.8% (12/153) between Vitek 2 Compact method and MALDI-TOF MS combined with Sepsityper Kit,and 75.1% (101/153) and 8.5% (13/153) between Vitek 2 Compact method and MALDI-TOF MS combined with serum-separating gel tubes. In the identification of single bacterial infection specimens, the consistency rates of MALDI-TOF MS combined with Sepsityper Kit at species and genus levels were 95.2% (79/83) and 0% (0/83) for gram-negative bacteria,57.5% (27/47) and 23.4% (11/47) for gram-pos-itive bacteria and 33.3% (3/9) and 11.1% (1/9) for Candida,the consistency rates of MALDI-TOF MS combined with serum-separating gel tubes at species and genus levels were 90.4% (75/83) and 4.8% (4/83) for gram-negative bacteria,55.3% (26/47) and 14.9% (7/47) for gram-positive bacteria and 0% (0/9) and 22.2% (2/9) for Candida. MALDI-TOF MS combined with Sepsityper Kit was only consistent with Vitek 2 Compact method in the identification of one specimen of multiple bacterial infections. Conclu-sion MALDI-TOF MS in combination with Sepsityper Kit or serum-separating gel tubes can identify the pathogens positive for blood culture within one hour and is of high consistency with culturing. In comparison with the traditional identification method for positive blood cultures, MALDI-TOF MS combined with Sepsi-typer Kit or serum-separating gel tubes has the advantages of rapidity and easy operation, which meet the clinical needs of rapid diagnosis and timely and effective antibacterial treatment,and is of great value in clin-ical application.
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To dynamically investigate the distribution and antimicrobial resistance profiles of bacteremia pathogens isolated from different regions in China in 2011, 2013 and 2016. Non-repetitive isolates from nosocomial bloodstream infections were retrospectively collected and detected for antimicrobial susceptibility tests (AST) by agar dilution or microbroth dilution methods. Whonet 5.6 was used to analyze the AST data. Among 2 248 isolates, 1 657 (73.7%) were Gram-negative bacilli and 591 (26.3%) were Gram-positive cocci. The top five bacteremia pathogens were as follows, Escherichia coli (32.6%, 733/2 248), Klebsiella pneumoniae (14.5%, 327/2 248), Staphylococcus aureus (10.0%, 225/2 248), Acinetobacter baumannii (8.7%, 196/2 248) and Pseudomonas aeruginosa (6.2%, 140/2 248). Colistin (96.5%, 1 525/1 581, excluding innate resistant organisms), tigecycline (95.6%, 1 375/1 438, excluding innate resistant organisms), ceftazidine/clavulanate acid (89.2%, 1 112 /1 246), amikacin (86.4%, 1 382/1 599) and meropenem (85.7%, 1 376/1 605) showed relatively high susceptibility against Gram-negative bacilli. While tigecycline, teicoplanin and daptomycin (the susceptibility rates were 100.0%), vancomycin and linezolid (the susceptibility rates were 99.7%) demonstrated high susceptibility against Gram-positive cocci. The prevalence of extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriaceae were 50.6% (206/407), 49.8% (136/273) and 38.9% (167/429) in 2011, 2013 and 2016 respectively; carbapenem-non-susceptible Enterobacteriaceae were 2.2% (9/408), 4.0% (16/402) and 3.9% (17/439) in 2011, 2013 and 2016 respectively; The prevalence of multidrug-resistant A. baumannii (MDRA) was 76.4% (55/72) in 2011, 82.7% (43/52) in 2013 and 87.5% (63/72) in 2016, respectively. The prevalence of multidrug-resistant P. aeruginosa (MDRP) was 9.8% (5/51) in 2011, 20.0% (7/35) in 2013 and 13.0% (7/54) in 2016, respectively. The prevalence of methicillin-resistant S. aureus (MRSA) was 51.9% (41/79) in 2011, 29.7% (19/64) in 2013 and 31.7% (26/82) in 2016, respectively. The prevalence of high level gentamicin resistance (HLGR) of Enterococcus faecium and Enterococcus faecalis were 43.2% (48/111) and 40.9% (27/66), respectively. The predominant organism of carbapenem-non-susceptible Enterobacteriaceae was K. pneumoniae with its proportion of 57.1% (24/42). Among 30 tigecycline-non-susceptible Enterobacteriaceae, K. pneumoniae was the most popular organism with 76.7% (23/30). Among 39 colistin-resistant Enterobacteriaceae, E. coli, Enterobacter cloacae and K. pneumoniae were constituted with the percent of 43.6 (17/39), 35.9 (14/39) and 15.4 (6/39), respectively. The Gram-negative bacilli (E. coli and K. pneumoniae were the major organisms) were the major pathogens of nosocomial bacteremia, to which tigecycline, colistin and carbapenems kept with highly in vitro susceptibility. Whereas, among the Gram-positive cocci, S. aureus was the top 1 isolated organism, followed by E. faecium, to which tigecycline, daptomycin, linezolid, vancomycin and teicoplanin kept with highly in vitro susceptibility. Isolation of colistin-resistant Enterobacteriaceae, tigecycline-non-susceptible Enterobacteriaceae, linezolid- or vancomycin-non-susceptible Gram-positive cocci suggests more attention should be paid to these resistant organisms and dynamic surveillance was essential.
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To investigate the resistance mechanisms of tigecycline-non-susceptible Acinetobacter baumannii and for providing the evidence of the control of nosocomial infection and rational use of antibiotics. The minimum inhibitory concentrations (MICs) of 94 non repetitive tigecycline-non-susceptible A. baumannii from 20 hospitals in 12 cities of China were determined by agar dilution method and broth microdilution method. The molecular epidemiology was studied by Multilocus sequence typing (MLST) and eBURST software. PCR and sequencing techniques were used to analyze the resistance genes (blaOXA-40-like, blaOXA-58-like, blaOXA-23-like, blaOXA-51-like, blaNDM-1), ISAba1, and the mutation sites of adeR, adeS, and trm. The activity of polymyxin B and minocyclinem against tigecycline-non-susceptible A. baumannii were 100% and 25.5%, respectively. The sensitivities of other antibiotics were less than 3.5%, and the sensitivities of imipenem and meropenem totigecycline-nonsusceptible A. baumannii were only 1.1%. A total of 12 ST types were identified, including ST195 (45, 47.9%), ST208 (19, 20.2%) and ST457 (10, 10.6%). EBURST analysis found that 8 of the ST types belonged to the clone complex 92 (Clonal Complex 92, CC92). The blaOXA-23-like type carbapenem gene was identiefied in 93 strains (99% positive); and none of the strains contained the blaNDM-1 gene. The detection rates of adeR and adeS were 73.4% and 91.5% respectively and high frequency mutation sites were located in adeR (Asp26Asn) and adeS (Ala97Glu); The ISAba1 located upstream of the adeS gene was detected in 12 strains of A. baumannii, mainly from the northern region of China. The 240 nucleotide deletion of the trm gene caused a frameshift leading to a premature stop. So the tigecycline-non-susceptible A. baumannii showed high resistance against most antibiotics except polymyxin B. The deletion and mutation of adeR, adeS and trm were the main resistant mechanisms in tigecycline-non-susceptible A. baumannii in China.
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Surgery,hypothermia,blood transfusion,pain,anxiety,the choice of anesthesia drugs and anesthetic techniques can affect the patient's immunolosical function.Especially for cancer patients,inhibition of the perioperative immunolosical function can make the residual tumor cell metastasis and recurrence,affecting long-term prognosis and reducing quality of life.Therefore,clinicians need to evaluate and improve immunolosical function in cancer patients by several aspects.
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Clinical microbiology tests play an important role in the etiological diagnosis and treatment of infectious diseases, monitoring and alerting of nosocomial infection, rational use of drugs and drug sensitivity monitoring.Microbiology laboratory should strengthen the application and popularization of techniques for rapid diagnosis and point-of-care diagnosis, and intensify the quality control.With patients-oriented principle, microbiology laboratory should enhance the communications with clinicians to better serve the diagnosis and treatment of infectious diseases.
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Objective To analyze the genotype and molecular epidemiology of carbapenem-resistant Enterobacteriaceae.Method A total of 201 carbapenem-resistant Enterobacteriaceae were isolated from 14hospitals in 11 cities.The MICs of 14 antimicrobial drugs were detected using agar dilution method.Phenotypes of carbapenemases were screened using modified Hodge test and ethylene diamine tetraacetic acid (EDTA) test.Drug resistance genes were screened using PCR method.The strains carrying carbapenem resistance genes were confirmed by conjugation test.Homology analysis was carried out using pulsed-field gel electro-phoresis (PFGE) method and the epidemiological correlation is analyzed based on the Multilocus Sequence Typing (MLST) method in order to study the molecular epidemiology of carbapenem-resistant Enterobacteriaceae.Results Fifty-three strains among 201 carbapenem-insensitive Enterobacteriaceae were detected positive carbapenem-resistant genes,among which included 33 Klebsiella pneumoniae,9 Citrobacter freundii,6 Escherichia coli and 5 Enterobacter cloacae.Among the 53 strains,43 were from Beijing,6 strains from Hangzhou,3 strains from Nanjing and one from Fuzhou.Resistance genes-harboring plasmids were successfully transferred from 28 of 53 strains to Escherichia coli EC600.The PFGE spectmm showed that 33 Klebsiella pneumoniae were classified into three types,9 Citrobacterfreundii classified into four types,5 Enterobacter cloacae classified into four types,while 6 Escherichia coli were the same type.Based on the results of MLST test,29 Klebsiella pneumoniae strains producing KPC-2 type carbapenemase were all ST11,while among the four Klebsiella pneumonia carrying IMP-4 carbapenem resistant gene,three strains were ST876,one was ST147.Conclusions Carbapenem-resistant genes were detected only in hospitals from Beijing,Hangzhou,Nanjing and Fuzhou,and type KPC-2 was the most common,followed by IMP-4 and IMP-8.High homology of resistant strains could be related to horizontal transfer of carbapenemase genes,which should cause great concern.
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Objective To investigate the expression of CKLF-like MARVEL transmembrane (CMTM)domain-containing family in clear cell renal cell carcinoma(ccRCC)and its significance.Methods Seventy-five samples of ccRCC were collected,including 50 males and 25 females,mean age (59 ± 10)years.There were 34 cases in clinical stage Ⅰ,23 cases in stage Ⅱ,14 cases in stage Ⅲ and 4 cases in stage Ⅳ.The pathological differentiation was 3 cases of grade Ⅰ,1 case of grade Ⅰ-Ⅱ,35 cases of grade Ⅱ,10 cases of grade Ⅱ-Ⅲ,18 cases of grade Ⅲ,3 cases of grade Ⅲ-Ⅳ and 5 cases of grade Ⅳ.The expression of CMTM3 and CMTM5 proteins in 75 cases of ccRCC and corresponding adjacent normal kidney tissues was detected by tissue microarray and immunohistochemistry.Results The positive expression rate of CMTM3 and CMTM5 was 98.7％,97.3％ in the adjacent normal kidney tissues,and 44.0％,68.0％ in ccRCC tissues(P ＜ 0.05).The expression of CMTM3 and CMTM5 had no correlation with the gender,age,clinical staging and pathological differentiation(P ＞ 0.05).Conclusion CMTM3 and CMTM5 could be ccRCC suppressor genes,and their mutation or methylation might be an early event in the carcinogenesis of ccRCC,thus promise them to be potential biomarkers in early diagnosis.
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Objective To identify critical genes in evolution of Staphylococcus aureus (S.aureus).Methods A total of 2457 genes from two whole genomes of S.aureus strains were amplified for fabricating whole genome microarray,which was employed for comparative genome hybridization (CGH) analysis of 23 strains of divergent MRSA clones,including ST239-spa t037 and ST239-spa t030.Representatives of differential genes were confirmed by PCR.Results Four gene clusters were identified to be associated with evolution of major epidemic MRSA clones.The four gene clusters were specific to ST239-spa t030,and belonged to three known genomic islands (vSa4,prophage ΦSa1 and ΦSa3).Eight genes were variable expressed in ST239-spa t030 MRSA from different coutries.Conclusion The acquisition of genomic islands vSa4,prophage ΦSa1 and ΦSa3 enhanced the virulence and resistance of ST239-spa t030 MRSA,and contributed to its rapid replacement of ST239-spa t037 MRSA in China.
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Objective:To observe the effect of Jiedu Huoxue Prescription on gastrin of atrophic gastritis rats. Methods:The atrophic gastritis rats model was established by using combination of MNNG, sodium salicylate, hot saline water and irregular diet. The blood serum gastrin content was detected with RI. Results: Compared with model group, the contents of gastrin in Jiedu Huoxue Prescription group, sanjiu group and weimeisu group increased significantly (P