Clinical evaluation of direct drug sensitivity test for blood culture positive broths / 中华检验医学杂志

Objective:To evaluate the clinical performance of direct antimicrobial susceptibility test in blood culture-positive broth, and to provide a basis for optimizing the antibiotic use strategy in clinical bloodstream infection.Methods:A retrospective analysis was conducted on 780 blood culture-positive samples collected in Peking University People′s Hospital from May 2017 to December 2021. The direct antimicrobial susceptibility test was performed by disk diffusion method on blood culture-positive broth. The antimicrobial susceptibility breakpoints were in accordance with Clinical and Laboratory Standards Institute (CLSI) M100 S32 edition document.Results:In this study, a total of 331 strains of Gram-negative bacteria (139 strains of Escherichia coli, 79 strains of Klebsiella pneumoniae, 35 strains of Pseudomonas aeruginosa, 21 strains of Acinetobacter baumannii) and 396 strains of Gram-positive cocci (25 strains of Staphylococcus aureus, 316 strains of coagulase-negative staphylococci, 47 strains of Enterococcussp.) were collected, after excluding 53 cases with two or more isolates. Compared with the routine antimicrobial susceptibility test (AST), the rates of category agreement (CA), major error (ME), and very major error (VME) of Gram-negative bacteria were 86.0% (1368/1 591), 8.7% (139/1 591), and 0.5% (8/1 591), respectively. On the other hand, the CA%, ME%, and VME% of Gram-positive cocci were 89.2% (960/1 076), 7.5% (81/1 076), and 1% (11/1 076), respectively. Regarding the individual antimicrobial agents, the CA% of Escherichia coli was 16/17 for imipenem, 90.1% (109/121) for meropenem, and 70.8% (85/120) for cefepime. For Klebsiella pneumoniae, the CA% of was 10/13 for imipenem, 80.9% (55/68) for meropenem, and 80.3% (53/66) for cefepime. The CA% of meropenem in Pseudomonas aeruginosa and Acinetobacter baumannii were 96.0% (24/25) and 16/16. The CA% of linezolid and cefoxitin in Staphylococcus aureus were 100% (25/25) and 100% (24/24), respectively. The CA% of linezolid, cefoxitin and gentamicin in coagulase-negative staphylococci were 98.9% (269/272), 94.5% (277/293) and 71.6% (194/271) respectively. Finally, for Enterococcus sp., the CA% of vancomycin and ampicillin were 91.5% (43/47) and 94.7% (36/38), respectively. Conclusion:Compared with the conventional AST, the blood culture-positive broth direct AST exhibited high category agreement and low error rates for both Gram-negative bacteria and Gram-positive cocci, which can serve a rapid alternative for AST in cases of clinical bloodstream infection.

Effect evaluation of optimizing blood culture testing process / 中华检验医学杂志

Objective:To evaluate whether the time to positive (TTP), handling time after positive alarm and turnaround time (TAT) of bacteremia blood culture can be shortened by optimizing blood culture workflow.Methods:This study was conducted retrospectively. Positive blood culture samples collected from Peking University People′s Hospital from January 1, 2014 to June 30, 2021 were analyzed in stages. In the traditional process stage of this study (2014), 502 bottles of positive blood culture samples were included in the analysis. In the first stage of process optimization (2016), the working time of staff was increased to 22:00, and 976 positive blood culture specimens were included in the analysis. In the second stage of process optimization (2018), the rapid identification process of MALDI-TOF MS was added, and a total of 1 029 bottles of positive blood culture samples were included. In the third stage of process optimization (2020) with the introduction of the new VIRTUO BACT/ALERT system. The difference of TTP, handling time after positive alarm and TAT of whole process in different stages of traditional process and process optimization were compared. All data were statistically significant when P<0.05 using rank-sum test. Results:In the traditional process stage (2014), the median quartile time of handling time after positive alarm was 55.70 (47.35, 68.45) h. In the first stage of process optimization (2016), the median quartile time of handling time after positive alarm was 47.25 (33.88, 59.96) h, and the handling time after positive alarm in the first stage of process optimization was significantly shorter than that in the traditional process stage ( Z=?10.734, P<0.001). In the second stage of process optimization (2018), the median quartile time for handling time after positive alarm was 47.18(36.41, 59.40) h, and 12.18% of the preliminary identification results of Gram-negative bacilli before 17:00 could be reported to the clinic before audit. In the third stage of process optimization (2020), the median quartile of TTP and TAT were 39.56 (21.52, 62.65) h and 78.16(64.68, 99.72) h respectively in the original BACT/ALERT 3D system. The new VIRTUO BACT/ALERT system had a median quartile of 37.03(21.08, 58.22) h for TTP and 73.41(62.88, 89.48) h for TAT. VIRTUO BACT/ALERT 3D had a significantly shorter TTP than BACT/ALERT 3D ( Z=?2.273, P=0.023), the TAT of VIRTUO BACT/ALERT system was significantly shorter than that of BACT/ALERT 3D system ( Z=?4.040, P<0.001). Conclusion:By improving the blood culture process of microbiology laboratory in many aspects and measures, the processing time of blood culture in each stage can be shortened and clinical benefits can be obtained.

Prediction of bloodstream infection pathogens in hematopoietic stem cell transplantation patients by plasma microbial cell-free DNA sequencing / 中华检验医学杂志

Objective:To predict the pathogens of bloodstream infection (BSI) in hematopoietic stem cell transplantation (HSCT) patients by plasma microbial cell-free DNA (mcfDNA) sequencing with and without additional amplification.Methods:A total of 978 HSCT patients were enrolled in Peking University People′s Hospital from March to July 2021, and the 7 428 blood samples were prospectively collected from pretransplant conditioning period to 4 months after transplantation. The plasma samples were separated and then cryopreserved. According to blood culture results and whether there were plasma samples before BSI onset, twenty-eight HSCT patients with positive blood culture (39 plasma samples within 1-8 days before BSI onset) and 9 HSCT patients with negative blood culture (9 plasma samples) were filtered. The 39 samples were performed with mcfDNA additional and non-additional amplification sequencing, and the 9 samples were only performed with additional amplification sequencing. With the blood culture results as the gold standard, the consistency between the sequencing and the blood culture results was observed. Student t test and Wilcoxon test were used for statistical analysis. Results:Without additional amplification sequencing, only 7 samples sequencing results were consistent with the blood culture results, and the total pathogen detection rate was 17.95% (7/39). The rates within 3 days and 4-8 days were 23.81% (5/21) and 2/18, respectively. The main pathogenic type detected was gram-negative bacteria (5/7). With additional amplification sequencing, the total pathogen detection rate was 59.26% (16/27) and the rate within 3 days was 8/13. The number of gram-positive bacteria detected was elevated (13/16) and the number of additional microorganisms in additional amplification sequencing was increased significantly ( P=0.001 0), compared with non-additional amplification sequencing. Moreover, additional sequencing analysis of 9 samples from patients with negative culture result showed that no pathogen was detected in six samples, and the common Torque teno virus in HSCT patients was detected in only three samples. Conclusion:The pathogen detection rate of plasma mcfDNA additional amplification sequencing was better than that of non-additional amplification sequencing in HSCT patients before BSI onset, especially in the first three days, which has the potential to predict BSI pathogens.

Comparison of elastic syndesmosis hook plate and suture-button technique in treatment of syndesmosis injury / 中华创伤骨科杂志

Objective:To compare our self-designed elastic syndesmosis hook plate (ESHP) and suture-button technique in treatment of injury to the distal tibiofibular syndesmosis.Methods:A retrospective study was conducted of the 53 patients who had been treated at Military Orthopaedic Center, 909 Hospital of Joint Service Support Force of PLA for ankle fractures complicated with syndesmosis injury by ESHP or suture-button technique from March 2013 to March 2017. Of them, 28 were treated by ESHP (ESHP group: 15 males and 13 females aged from 26 to 60 years) and 25 by suture-button technique (suture-button group: 14 males and 11 females aged from 24 to 59 years). The 2 groups were compared in terms of syndesmosis fixation time, postoperative incision bleeding, hospital stay, and ankle dorsiflexion and plantarflexion and ankle function by Baird-Jackson scoring at 3, 6, 12 months after surgery. Postoperative complications were observed.Results:The 2 groups were comparable because there was no statistically significant deference in general data between the 2 groups ( P>0.05). Surgery went on uneventfully in all the patients. The syndesmosis fixation time [(9.7±2.2) min] and postoperative incision bleeding [(49.3±10.4) mL] in the ESHP group were significantly less than in the suture-button group [(16.2±1.4) min and (62.4±6.3) mL] ( P<0.05); the maximum plantar flexion (29.9°±1.3°) and Baird-Jackson scores (87.2±2.9) at 3 months after surgery in the ESHP group were significantly greater than in the suture-button group (22.8°±1.3° and 78.7±4.1) ( P<0.05). There were no significant differences between the 2 groups in hospital stay, maximum plantar flexion at postoperative 6 or 12 months, maximum dorsiflexion at postoperative 3, 6 or 12 months, or Baird-Jackson scores at postoperative 6 or 12 months (all P>0.05). This cohort was followed up for 12 to 14 months (average, 12.5 months). All fractures united during follow-up and all the implants were removed around postoperative 12 months. Follow-up within 12 months observed internal fixation failure caused by metal fatigue in one case in the ESHP group, and internal fixation irritation in one case, internal fixation failure in 2 cases and internal fixation sinking and osteolysis in one case in the suture-button group. Conclusion:Compared with the suture-button technique, treatment of injury to the distal tibiofibular syndesmosis with ESHP may lead to shorter fixation time, less postoperative bleeding and complications, and faster functional recovery of the ankle.

Characteristics of influenza A (H3N2) virus hemagglutinin genes in Fujian province from 2014 to 2016 / 中华微生物学和免疫学杂志

Objective To investigate the genetic characteristics and mutations in hemagglutinin ( HA) genes of influenza A subtype H3N2 viruses isolated in Fujian province during 2014—2016. Methods HA gene fragments of 44 randomly selected influenza A (H3N2) viruses were amplified by RT-PCR and then sequenced by Sanger sequencing. Obtained sequences were analyzed by bioinformatics software and on-line websites. Results Pair-wise similarity among HA genes of the 44 strains was between 97. 3%-100. 0% at nucleotide level. The average variations between epidemic strains and corresponding vaccine strains in the year of 2014, 2015 and 2016 were 0. 012, 0. 008 and 0. 009, respectively. The genotype of epidemic strains in 2014 was 3C. 3a rather than 3C. 1 of the vaccine strain. Notably, variations at some antigenic sites, re-ceptor binding sites ( RBSs) and N-Glycosylation sites were identified despite the fact that the genotypes were identical between epidemic and vaccine strains in 2015 and 2016. Conclusion Variations at the HA genes of influenza A (H3N2) viruses in Fujian province occurred during the year of 2014—2016, reflecting the ability of circulating strains to escape the vaccine-induced immunity. Sustainable influenza surveillance and prompt identification of viral variants would benefit influenza prevention and control.

Rapid identification of pathogenic organisms positive for blood culture by MALDI-TOF mass spec-trometry in combination with Sepsityper Kit or serum-separating gel tubes / 中华微生物学和免疫学杂志

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.

Antitumor effect of 131 I-labeled anti-VEGFR2 targeted nanoparticles in anaplastic thyroid carcinoma mouse models / 中华核医学与分子影像杂志

Objective To investigate the radioactivity distribution of 131 I-bovine serum albumin ( BSA )-mesoporous silica nanoparticles ( MSNs )-anti-vascular endothelial growth factor receptor 2 (VEGFR2) in anaplastic thyroid carcinoma (ATC) and to explore its antitumor efficacy in ATC-bearing nude mouse models. Methods 131 I-BSA-MSNs-anti-VEGFR2 and 131 I-BSA-MSNs were constructed. FRO tumor xenografts were established and the SPECT/CT images of tumor-bearing mice were acquired at differ-ent time points after intratumoral injection with 131 I-BSA-MSNs-anti-VEGFR2 ( targeting group) , 131 I-BSA-MSNs ( non-targeting group) , Na131 I ( Na131 I group) and saline ( control group) , respectively. The changes of body mass and tumor volume in each group were recorded. Two-sample t test and log-rank test were used to analyze the data. Results After incubation for 3 h, the fluorescence intensity in targeting group was higher than that in non-targeting group (345.26±16.35 vs 280.61±9.65;t=5.90, P<0.05). After injection for 1-3 weeks, the radioactivity detected by SPECT/CT in targeting group was obviously stronger than that in non-targeting group ( t values:7.060-12.780, all P<0.05) . At the end of the observation, the tumor vol-ume of Na131I group, control group, non-targeting group and targeting group increased to (278.3±19.3)％, (296.6±24.2)％, (198.7±13.2)％ and (103.7±6.2)％ of the original volume, respectively. The body mass of the first 2 groups decreased to (88.6±3.0)％ and (86.2±3.1)％ of the original body mass respec-tively, while that of the latter 2 groups increased to (102.1±3.1)％ and (116.2±3.4)％ of the original body mass respectively. Survival analysis showed that the median survival time in targeting group ( 38 d) was sig-nificantly longer than that in non-targeting group (34 d;χ2=8.05, P<0.05). Conclusion 131I-BSA-MSNs-anti-VEGFR2 can effectively inhibit the tumor growth of ATC and prolong the survival of tumor-bearing nude mice, which gives a good suggestion for the treatment and prognosis evaluation of ATC.

Microbiological profiles of pathogens causing nosocomial bacteremia in 2011, 2013 and 2016 / 生物工程学报

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.

Loboratory diagnosis and preliminary viral sequence analysis of the first case of human infection with avian influenza A (H5N6) virus in Fujian province / 中华实验和临床病毒学杂志

Objective@#To provide effective reference of laboratory detection and prevention-control in avian influenza epidemic via analyzing the detection result of the first case infected avian influenza H5N6 virus in Fujian province.@*Methods@#The viral RNA was extracted from the patient’s throat swab and specimens of surrounding environment, and detected by real-time RT-PCR. The gene sequences of HA and NA gene segments were obtained by RT-PCR and sequencing, the evolution characteristics of the virus were elementarily analyzed by bioinformatics.@*Results@#The avian influenza H5N6 virus was confirmed from the patient’s throat swab, termed influenza A/Fujian-Sanyuan/21099/2017(H5N6)virus. The throat swabs of case from 5 different time points were collected and the H5N6 nucleic acid were detected from the first three times collection. Among 43 specimens of surrounding environment, there were 16 H5 virus samples. The HA and NA gene segments of A/Fujian-Sanyuan/21099/2017 were closely related to A/Cygnus atratus/Hubei/2Z2-O/2016(H5N8) and A/chicken/Hubei/ZYSJF16/2016(H5N6), with a similarity of 99.6% and 99.0% respectively. The cleavage site of HA gene contained multiple basic amino acids.@*Conclusions@#The suspected case was the first case infected with avian influenza H5N6 virus in Fujian province, and the HA and NA genes of virus were highly similar to those of H5N8 and H5N6 virus respectively.

A retrospective evaluation of the performance of 2 blood culture media in detection of bloodstream infection: clinical comparison of BACTEC and BacT/Alert systems / 中华检验医学杂志

Objective To evaluate the clinical performance of the BACTEC Plus aerobic,BACTEC Lytic anaerobic,BacT/Alert aerobic and anaerobic blood culture media in detection of bloodstream infections.Methods Retrospective study was conducted.A total of four blood culture bottles from each inpatient with suspected bloodstream infections were collected and analyzed from June 2013 to September 2015 in Peking University People's Hospital.The four bottles,including BACTEC Plus aerobic,BACTEC Lytic anaerobic,BacT/Alert FA aerobic and BacT/Alert FN anaerobic media,and was incubated for 5 days in the BacT/Alert 3D and BACTEC FX instruments,respectively.Time to detection (TTD) and positive rate in detecting bacteria of the two systems were evaluated by Wilcoxon test and Chi-square test.Results Among 2 189 total cultures collected,20 were excluded because of blood shortage and 201 (9.27％) were positive for pathogens.The positive rates of BACTEC Plus aerobic media and BacT/Alert FA aerobic media were 75.3％ (140/186) and 69.4％ (129/186) (x2 =1.625,P=0.202),respectively.While,the positive rates of BacT/Alert FN anaerobic media and BACTEC Lytic anaerobic media were 81.8％ (99/121) and 63.6％ (77/121) for total organisms,respectively (x2 =10.083,P =0.001).A significant difference in TTD was detected in BACTEC Plus aerobic media[11.0 (8.0-16.0) h] and BacT/Alert FA aerobic media[13.9 (10.4-18.7) h] (Z =-5.240,P ＜ 0.001).BACTEC Lyric anaerobic media[8.0(7.0-10.0) h] had a shorter TTD (Z =-4.299,P ＜ 0.001) than BacT/Alert FN anaerobic media[11.3(9.3-12.7) h].The positive rates of BACTEC and BacT/Alert system were 74.13％ (149/201) and 74.63％ (150/201),respectively,compared with taking one set from each system.Conclusions BACTEC media has a shorter TTD and almost the same bacterial recovery,and lower false positive rate than the BacT/ Alert media.

Complete genome analysis of influenza A(H1N1) pdm09 virus isolated from one case of pneumonia of unknown etiology (PUE) in Fujian Province, China / 中国人兽共患病学报

To study the biological characteristics and mutations of influenza A(H1N1)pdm09 virus isolated from one case of pneumonia of unknown etiology (PUE),which would provide references for clinical treatment and disease control,the throat swab specimen from the PUE case was isolated in the Madin-Darby Canine Kidney (MDCK) cells,and then the antigenicity,pathogenicity and drug resistance of influenza A (H1N1) pdm09 virus were analyzed after sequencing.As a result,one influenza virus strain was isolated from the specimen and named as A/FujianGulou/SWL64/2016(H1N1).The similarities of nucleotide sequences and amino acids sequences compared with the vaccine strain A/California/07/2009 (H1N1) were 96.9％-98.9％ and 96.7％-99.5％,respectively.Eighteen amino acids had mutated in the HA and 4 mutations,K163Q,S185T,S203T and D222N,were involved in 3 different epitopes,which indicated that the antigenic drift had occurred in the influenza virus.The D222N mutation associated with receptor binding site made the virus infect lower respiratory tract more easily.The virus was still amantadine-resistance and oseltamivir-sensitive.In conclusion,the influenza A (H1N1) pdm09 virus in this study have occurred antigenic drift and has the molecular characterization of causing severe pneumonia,so further surveillance should be performed to prevent and control the influenza epidemic.

The correlation studies of the Lp-PLA2,hs-CRP and D-dimmer in patients with coronary heart disease / 国际检验医学杂志

Objective To study the correlations among the lipoprotein associated phospholipase A2 (Lp‐PLA2) ,hypersensitive C‐reactive protein(hs‐CRP)and D‐dimmer in patients with the coronary heart disease .Methods 260 cases of patients with coronary heart disease(CHD) were enrolled in the study as observation group and 260 healthy people from the physical examinations were recruited as control group .The concentrations of Lp‐PLA2 ,hs‐CRP ,D‐dimer and other biochemical indicators in blood sera of the two groups were detected ,using the Spearman correlation analysis to test the relationship between those indicators .Results The Lp‐PLA2 ,hs‐CRP ,D‐dimer levels of the observation group were obviously higher than those of control group .The Lp‐PLA2 level of the observation group was positively correlated with the cardiac function index(r=0 .873 ,P<0 .05) .hs‐CRP was positively cor‐related with cardiac function index(r=0 .782 ,P<0 .05) .D‐dimmer was positively correlated with the functional grades of heart(r=0 .674 ,P<0 .05) .Conclusion Lp‐PLA2 ,hs‐CRP and D‐dimer could be important indicators for the detection of coronary heart disease .

Molecular mechanisms of colistin-resistant Klebsiella pneumoniae and Escherichia coli isolates / 中华检验医学杂志

Objective To elucidate the resistance mechanisms of clinical colistin-resistant Klebsiella pneumoniae and Escherichia coli isolates in China.Methods A total of 964 K.pneumoniae and 1 389 E. coli isolates were retrospectively collected from national surveillance programs from 2011 to 2014 in China. Antimicrobial susceptibility testing was determined by the microdilution method.The PCR amplification followed by sequencing was used to detect the mcr-1 gene and colistin-resistance genes, including mgrB, pmrB and phoQ.Real-time quantitative PCR was performed to examine the relative transcriptional levels of pmrB, pmrC, pmrD, pmrK and pmrE genes in K.pneumoniae, and pmrA, pmrB, pmrC, phoP and phoQ genes in E.coli.Conjugation experiment was used to detect the transferability of the resistance plasmid carrying the mcr-1 gene.Statistical analyses were performed using IBM SPSS Statistics (version 16.0) and a P value <0.05 was considered statistically significant. Results The colistin-resistant rates of K. pneumoniae and E.coli were 0.62% ( 6/964 ) and 1.66% ( 23/1 389 ) , respectively.No amino acids substitutions were identified in mgrB genes among colistin-resistant isolates.Among six colistin-resistant K. pneumoniae isolates, five isolates were identified to have point mutations in pmrB gene, but no point substitution was detected in phoQ gene.One to four point mutations had been found in pmrB and phoQ genes in colistin-resistant E.coli isolates, respectively.The expression level of pmrB, pmrC, pmrD, pmrK and pmrE genes showed no significant difference between colistin-resistant and colistin-susceptible isolates [pmrB, (1.04 ±1.12) vs.(0.94 ±0.67), P=0.945; pmrC, (1.39 ±2.01) vs.(0.16 ±0.27), P=0.101;pmrD, (1.59 ±2.43) vs.(0.88 ±0.34),P=0.445;pmrK, (0.64 ±0.62) vs.(0.04 ±0.10), P=0.051;pmrE, (3 492 833 388.83 ±8 478 977 986.85) vs.(20 771 428.93 ±38 000 732.85), P=0.445].However, the transcriptional level of pmrB genes in colistin-resistant group was 9.5-fold higher than that of the colistin-susceptible group in E.coli isolates.Four in six colistin-resistant K.pneumoniae isolates possessed mcr-1 gene, whereas all of the colistin-resistant E. coli had the mcr-1 gene. The conjugation verified the transferability rate of the plasmid carrying mcr-1 gene was 5.78 ×10-6 , and the MIC value of colistin of the conjugant increased 21-fold than the recipient strain.Conclusions Plasmid-mediated mcr-1 gene was the major reason for colistin resistance in clinical isolates of K.pneumoniae and E.coli. Some other resistance mechanisms such as transcriptional up-regulated pmrB gene also involved in colistin resistance.

Fst statistical method for evaluating KIF1B gene rs17401966 polymorphism and heterogeneity source of hepatocellular carcinoma risk meta-analysis / 国际检验医学杂志

Objective To adopt Fst statistical method to assess the heterogeneity sources of meta‐analysis by dichotomous varia‐ble .Methods The case‐control studies on the relationship between KIF1B gene rs17401966 polymorphism and hepatocellular carci‐noma(HCC) risk were collected by retrieving the databases including Google Scholar ,EMBASE ,PubMed ,ISI Web of Knowledge and CNKI .The meta analysis was performed by using the Stata12 .0 software .The genetic differentiation degree among populations was analyzed and researched by using the Arlequin 3 .5 software .Results A total of 5 case‐control studies were finally included ,in‐volving 12 research populations .The meta analysis on 12 populations showed that KIF1B gene rs17401966G allele was negatively correlated with HCC risk (OR=0 .77 ,95% CI:0 .65-0 .93 ;P=0 .005) .However ,the strong heterogeneity existed in this pooled re‐sults .The genetic differentiation test in the included 12 populations found that Zhang′s five research populations had varying de‐grees of genetic differentiation compared to other populations .Then the proper subgroup analysis was further conducted based on Fst value ,and then the I2 value of the heterogeneity test in the group 8 and 9 was descended to less than 25% .However ,the meta analysis results of the group 8 and 9 were inconsistent .Conclusion This study showed that conducting the meta‐analysis of KIF1B gene rs17401966 polymorphism and the HCC risk can find the heterogeneity sources of meta‐analysis by conducting the genetic dif‐ferentiation test in the included population .

Efficacy of endoscopic histoacryl injection in treatment of gastric variceal bleeding caused by regional portal hypertension / 临床肝胆病杂志

ObjectiveTo analyze the efficacy of endoscopic histoacryl injection in the treatment of gastric variceal bleeding caused by regional portal hypertension. MethodsThe endoscopic features and efficacy of endoscopic histoacryl injection were examined and compared in two groups of patients admitted to our hospital from June 2012 to December 2012. One of the groups included 6 patients with gastric variceal bleeding caused by regional portal hypertension and the other group included 6 patients with gastric variceal bleeding caused by hepatitis B cirrhosis-related portal hypertension. Between-group comparison of categorical data was made by Fisher′s test. ResultsIn patients with regional portal hypertension, five of them had severe isolated gastric varices (IGV) and one had severe IGV with mild esophageal varices. All six patients with hepatitis B cirrhosis-related portal hypertension had severe IGV and the endoscopic features were similar to those of patients with regional portal hypertension. Significant differences were observed between the group with regional portal hypertension and the group with hepatitis B cirrhosis related portal hypertension in short-term response rate (1/6 vs 6/6, P=0.015) and long-term response rate (0/6 vs 5/6, P=0.015). ConclusionThe gastric varices caused by regional portal hypertension has a fast progression rate and a high bleeding risk. The efficacy of endoscopic histoacryl injection in patients with this type of gastric varices is poor.

Antibiotic-resistant genes and multilocus sequencing typing of Pseudomonas aeruginosa / 中国人兽共患病学报

We investigated the antibiotic‐resistant genes and genetic diversity of Pseudomonas aeruginosa from patients in hospital ,the smear samples from hospital and clinic environment ,and from medical staff’ hands respectively in 2011‐2012 in Nanshan District of Shenzhen .Polymerase chain reaction were used to detect the 20 kinds of antibiotic‐resistant genes (TEM , VEB,CARB,OXA,SHV,PER,GES,GTX,SPM,GIM,IMP,VIM,DHA,oprD,Aac(6′)‐Ⅰ ,Aac(6′)‐Ⅱ ,Aac (3′)‐Ⅰ ,A ac(2″)‐Ⅰ ,qacE1‐sull and int‐Ⅰ) .Multilocus sequencing typing was used to analyze the clonal complexes .The 11 kinds resistant genes TEM ,SHV ,IMP ,DHA ,Aac(6′)‐Ⅰ ,Aac(6′)‐Ⅱ ,Aac(3′)‐Ⅰ ,Aac(2″)‐Ⅰ ,qacE1‐sull ,int‐Ⅰand oprD were detected ,for the positive rates respectively ,and which were 8 .1% ,6 .4% ,4 .8% ,9 .7% ,4 .8% ,14 .5% ,9 .7% , 56 .5% ,8 .1% ,and 8 .1% ;the loss rate of oprD gene was 61 .2% .The 19 antibiotic resistance gene profiles existed in 52 Pseudomonas aeruginosa strains .Multilocus sequencing typing found 39 sequence types and 5 clonal complexes in 62 Pseudo‐monas aeruginosa strains ,CC244 and ST856 were dominant .There were some differences of antibiotic resistance gene profiles between different samples ,the Pseudomonas aeruginosa strains from patients carried multiple resistant genes .In our research , the Pseudomonas aeruginosa had the genetic diversity and the dominant clonal complexes existed .

Diagnostic and Therapeutic Value of Single-balloon Enteroscopy in Suspected Small Intestinal Diseases / 胃肠病学

Background:Single-balloon enteroscopy(SBE)is a new method for the examination of small intestine,its clinical value in suspected small intestinal diseases need to be further studied. Aims:To evaluate the diagnostic and therapeutic value of SBE in suspected small intestinal diseases. Methods:A total of 73 suspected small intestinal diseases patients who had undergone 81 SBE examinations from July 2011 to October 2013 at Chengdu Military General Hospital were retrospectively examined,indications,diagnostic and therapeutic value of SBE in suspected small intestinal diseases were analyzed. Results:Of all the 81 examinations,33(40. 7% )were obscure gastrointestinal bleeding,29(35. 8% ) incomplete intestinal obstruction,and 19(23. 5% )chronic abdominal pain or diarrhea. The intubation depth was 230 cm for the oral approach,and 100 cm for the anal approach. The diagnostic yield of SBE was 67. 9% ,the main lesions were small intestinal ulcer,small intestinal inflammation,small intestinal tumor,small intestinal polyp. A total of 8 patients underwent endoscopic therapy,of whom 5 underwent endoscopic hemostatic therapy and 3 underwent resection of polyp. No serious complications were found. Conclusions:SBE is a safe and reliable diagnostic and therapeutic method for suspected small intestinal diseases,and its main indications are obscure gastrointestinal bleeding and incomplete intestinal obstruction.

The retrospective study of oxacillin susceptible, mecA positive Staphylococcus aureus in China / 中华检验医学杂志

Objective The purpose of the study is to understand the epidemiology,distribution and molecular characteristics of oxacillin susceptible mecA positive Staphylococcus aureus (S.aureus).Methods Totally 1588 S.aureus isolates collected from 12 hospitals in 10 cities of China between 2010 and 2012 were retrospectively characterized.The isolates were characterized by antimicrobial susceptibility test of 20antimicrobial drugs.Three different methods (cefoxitin disc diffusion,agar dilution for oxacillin and cefoxitin) to detect oxacillin susceptible and mecA positive S.aureus were also compared.All the strains were confirmed to be S.aureus by detecting S.aureus specific genes by PCR (including nuc,femB,and mecA gene),which was viewed as the golden standard of MRSA.The molecular typing methods included SCCmec and spa typing.The statistical analyses were carried out in statistical product and service solutions (SPSS),Version 18.0.The significance level P was set at 0.05.Results According to the MICs of cefoxitin and oxacillin,a total of 60 isolates were oxacillin susceptible methicilin resistance Staphylococcus aureus (MRSA).Based on the differences of the specimen collection date,it is found that oxacillin susceptible MRSA have increased from 2010 to 2012 (P =0.05,95％ CI 0.045-0.056,X2 =6.099).These isolates were distributed in 9 major cities,and the highest prevalence is 30.0％ (18/60) in Guangzhou,followed by Beijing (18.3％,11/60),Wuhan (15.0％,9/60),Hangzhou (13.3％,8/60).Most of the isolates were from skin soft tissue infection (35％,21/60),blood stream infection (30％,18/60) and respiratory infection specimens (18.3％,11/60).The resistance rate to cefoxitin,erythromycin,clindamycin and tetracycline was 100％ (60/60),86.7％ (52/60),66.7％ (40/60) and 50％ (30/60),respectively.The molecular characterization showed that 21 spa and 5 SCCmec types were detected.The most predominant clone was spa t437-SCCmec Ⅳ (25.0％,15/60),followed by spa t437-SCCmecV (13.3％,8/60).Conclusions The detection rate of oxacillin susceptible MRSA is significantly higher from 2010 to 2012.The major clone is t437-SCCmec Ⅳ.The use of cefoxitin should replace oxacillin in detecting this type of MRSA.Further study is needed to confirm whether beta lactam antimicrobial agents should be used in the treatment of oxacillin susceptible mecA positive S.aureus.

Molecular characterization of St ap hy lococcus aureus in Yanbian / 中国感染与化疗杂志

Objective To investigate the molecular epidemiology of Staphylococcus aureus in Yanbian area .Methods From March 2011 to June 2012 ,a total of 101 consecutive and non-duplicate strains of Staphylococcus aureus were collected from Yanbian Hospital .Genotypes of SCCmec ,spa,and multilocus sequence typing (MLST) were determined by PCR combined with DNA sequencing analysis .The pvl gene was detected by PCR .Results The most prevalent SCCmec type was type II (65 .0% ,39/60) ,followed by SCCmec type III (26 .7% ,16/60) .A total of 11 Spa types were identified for the MRSA strains ,including t2460 (55 .0% ,33/60) ,t030 (18 .3% ,11/60) ,t002 ,t324 ,and t632 (5 .0% ,3/60 each) .A total of 29 Spa types were identified for MSSA strains ,including t796 (14 .6% ,6/41) ,t309 (9 .8% ,4/41) ,and t126 (7 .3% ,3/41) . The pvl gene was identified in 5 stains .MRSA strains were classified into three types based on multilocus sequence typing (MLST) ,namely ST5 ,ST239 and ST72 .MLST-based MSSA types were more diverse ,including ST5 ,ST 25 ,ST 15 ,ST 59 ,ST 1 ,ST 7 ,ST 45 ,ST 22 ,and ST 188 .Conclusions ST5-MRSA-SCCmecII-t2460 and ST239-MRSA-SCCmecIII-t030 are the most prevalent MRSA clones in Yanbian area .Multiple prevalent MSSA clones are identified.

The genotype and epidemiological feature of the Enterobacteriaceae carrying carbapenemase in China / 中华内科杂志

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.