Homology analysis on 62 strains of carbapenem-resistant Acinetobacter baumannii / 中国感染控制杂志

Objective To understand the homology of carbapenem-resistant Acinetobacter baumannii(CRAB)iso-lated from hospitalized patients in a hospital,and provide evidence for the prevention of CRAB spread in hospital. Methods Antimicrobial susceptibility testing of 62 strains of CRAB isolated from all kinds of clinical specimens from hospitalized patients between August 2015 and November 2016 was performed,homology and epidemic charac-teristics were analyzed by pulsed-field gel electrophoresis(PFGE).Results 62 strains of CRAB were mainly from sputum specimens(88.71%),all were resistant to ceftazidime,cefepime,imipenem,meropenem,and ciprofloxa-cin,resistance rate to levofloxacin was the lowest(25.81%). 62 strains of CRAB were divided into 14 different types(A-N),type B,D,E,J,and M only contained 1 strain respectively,type F contained 5 subtypes,type A,G,H,and K had 3 subtypes respectively,type C and I had 2 subtypes respectively.Clinical data of the main cloned strains were analyzed,32 strains(51.61%)were isolated from patients in intensive care unit(ICU),and 12 strains (19.35%)from patients who had ever stayed in ICU.Conclusion There are two forms of Acinetobacter baumannii prevailed in hospital,which are external and internal spread,infection control should be strengthened.

Bronchopulmonary Infection of Lophomonas blattarum: A Case and Literature Review

Human infections with Lophomonas blattarum are rare. However, the majority of the infections occurred in China, 94.4% (136 cases) of all cases in the world. This infection is difficult to differentiate from other pulmonary infections with similar symptoms. Here we reported a case of L. blattarum infection confirmed by bronchoalveolar lavage fluid smear on the microscopic observations. The patient was a 21-year-old female college student. The previous case which occurred in Chongqing was 20 years ago. We briefly reviewed on this infection reported in the world during the recent 20 years. The epidemiological characteristics, possible diagnostic basis, and treatment of this disease is discussed in order to provide a better understanding of recognition, diagnosis, and treatment of L. blattarum infection.

Construction of biofilm formation related mutants in Vibrio parahaemolyticus / 中华预防医学杂志

<p><b>OBJECTIVE</b>To construct the mutants of biofilm related genes in Vibrio parahaemolyticus and confirm the mutants.</p><p><b>METHODS</b>The homologous upstream and downstream flanking fragments of target gene were amplified by using PCR, and the fusion homologous fragment was amplified by using the two flanking fragments as template. Then the fusion homologous fragment was digested by restriction enzyme and cloned into suicide plasmid pDS132. The recombinant plasmid was transferred into Vibrio parahaemolyticus RIMD 2210633 through conjugation. The mutants were screened and identified by PCR and the phenotype of one mutant was analyzed in order to verify that the mutants were constructed successfully.</p><p><b>RESULTS</b>Six recombinant plasmids carrying the fusion homologous fragments of genes vbfR, crp, hns, swrZ, swrT and cpsR respectively were constructed and identified by PCR. The amplification products of 1190, 1128, 1136, 953, 1242 and 1112 bp were obtained respectively. The six mutants (ΔvbfR, Δcrp, Δhns, ΔswrZ, ΔswrT and ΔcpsR) were constructed using recombinant plasmids. Verified by PCR, the size of amplification products of mutants (1190, 1128, 1136, 953, 1242 and 1112 bp respectively) was less (610, 739, 421, 542, 427 and 1367 bp respectively) than the corresponding positive control. Meanwhile, none of the products was amplified using the primers locating on the target gene. One mutant Δhns was selected to test the ability of biofilm formation. The result showed that the ability of biofilm formation of mutant Δhns was increased compared with the wild type.</p><p><b>CONCLUSION</b>Six mutants of biofilm related genes in Vibrio parahaemolyticus were constructed and tested by molecular and phenotype experiment to confirm that the mutants were constructed successfully.</p>

Distribution of the of nosocomial infection pathogens among general hospital in China: a Meta analysis / 中华流行病学杂志

<p><b>OBJECTIVE</b>To provide basic and direction for nosocomial infection prevention and control through evaluation the distribution of nosocomial infection pathogens and understand current situation of pathogens among general hospital in China.</p><p><b>METHODS</b>Articles were searched and collected from CBM, CNKI,VIP database and Wanfang database published between creating database to March. 2013 about investigation of nosocomial infection. Those literatures were screened and extracted according to the inclusion and exclusion criteria by two reviewers independently. The analysis of pathogens distribution was performed by using comprehensive Meta analysis software and stratified by factor as year, hospital level and region of the study. The distribution rate of different pathogens were merged according to statistical tests for the heterogeneity test.</p><p><b>RESULTS</b>The 345 trials were included. The results show 1)the pooled distribution rates of common pathogens in 1987-2000 were as follows:18.6% (95% CI:13.7%-24.9%), 18.1% (95% CI:15.4%-21.0%), 14.8% (95% CI: 12.2%-17.9%), 5.2% (95%CI:4.1%-6.6%) for Fungus, Staphylococcus, Pseudomonas, and Klebsiella respectively;the pooled rates of common pathogens in 2001-2012 were as follows:17.6% (95% CI: 16.4%-18.8%), 15.0% (95% CI:14.2%-15.8%), 13.9% (95% CI:13.1%-14.7%), 10.4% (95% CI: 9.9%-11.0%)for Fungus, Staphylococcus, Pseudomonas, and Klebsiella respectively. 2)The pooled distribution rates of pathogens in second and below grade hospital were 3.2% (95%CI:0.3%-29.9%), 4.7% (95% CI:3.4%-6.3%), 7.2% (95% CI:1.7%-26.1%)for Mycoplasma, Shigella and Alkaligenes respectively;the pooled distribution rates of pathogens in third grade hospital were 1.1% (95% CI: 0.1%-15.4%), 1.8% (95%CI:0.6%-5.1%), 4.3% (95%CI:2.3%-8.0%)for Mycoplasma, Shigella and Alkaligenes respectively. 3)The pooled rate of Mycoplasma for Yangtze River Economic Area was 14.3% (95%CI:2.0%-58.1%)and for Southwest Economic Area was 0.3% (95%CI:0.1%-1.1%). The pooled rate of Corynebacterium for Yangtze River Economic Area was 0.4% (95%CI:0.1%-1.4%)and for Southeast Economic Area was 9.5% (95% CI:2.4%-31.1%). The pooled rate of Haemophilus for Northern Economic Area was 0.5% (95%CI:0.2%-0.9%)and for Southeast Economic Area was 9.2% (95% CI:7.3%-11.6%). The pooled rate of Salmonella for Yangtze River Economic Area was 6.3% (95% CI:4.6%-8.6% ) and for Southeast Economic Area was 0.4% (95% CI:0.1%-3.0% ).</p><p><b>CONCLUSION</b>The common nosocomial infection pathogens were Fungus, Staphylococcus, Pseudomonas and Escherichia among general hospitals in China. A remarkable note is that Klebsiella was increased significantly in recent years and becomes one of the most common pathogens. There were differences in the distribution rate of nosocomial infection pathogens among general hospitals between levels and regions in China.</p>

Use of rich BHI medium instead of synthetic TMH medium for gene regulation study in Yersinia pestis / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>This study is to verify the use of rich BHI medium to substitute synthetic media for gene regulation studies in Yersinia pestis.</p><p><b>METHODS</b>The transcriptional regulation of rovA by PhoP or via temperature upshift, and that of pla by CRP were investigated when Y. pestis was cultured in BHI. After cultivation under 26 °C, and with temperature shifting from 26 to 37 °C, the wild-type (WT) strain or its phoP or crp null mutant (ΔphoP or Δcrp, respectively) was subject to RNA isolation, and then the promoter activity of rovA or pla in the above strains was detected by the primer extension assay. The rovA promoter-proximal region was cloned into the pRW50 containing a promoterless lacZ gene. The recombinant LacZ reporter plasmid was transformed into WT and ΔphoP to measure the promoter activity of rovA in these two strains with the β-Galactosidase enzyme assay system.</p><p><b>RESULTS</b>When Y. pestis was cultured in BHI, the transcription of rovA was inhibited by PhoP and upon temperature upshift while that of pla was stimulated by CRP.</p><p><b>CONCLUSION</b>The rich BHI medium without the need for modification to be introduced into the relevant stimulating conditions (which are essential to triggering relevant gene regulatory cascades), can be used in lieu of synthetic TMH media to cultivate Y. pestis for gene regulation studies.</p>

Antibacteral effect of six Chinese traditional medicines on Yersinia pestis / 中国地方病学杂志

Objective To screen the antibacterial activity of Chinese traditional medicines against Yersinia pestis.Methods Six Chinese traditional medicines(Coptis Chinesis etc)were selected and extracted with pure water to make a concentration of 1 mg/L.Yersinia pestis strain 201 and EV 76 were used to determine the minimal inhibitory concentrations(MIC)of these selected medicines in vitro with liquid dilution method.Results Three herbs had inhibition effects on the strain 201 and EV76 in different extents,among which Rheum palmatum had the strongest effect and MIC was 0.025 00 mg/L.Furthermore,the Chinese traditional medicine had the same MIC on both strain 201 and EV76.Conclusions Chinese traditional medicines commonly used have inhibiting effect on Yersinia pesti.

Study of Rhubarb anti-Yersina pestis based on DNA microarray / 中国地方病学杂志

Objective To establish a method for studying molecular mechanism of Rhubarb inhibiting anti-Yersinia pesti based on DNA microarray.Methods A whole genome DN A microarray containing 4005 annotated genes of Yersiniapesti Was used.The minimal inhibitory concentration(MIC)of Rhubarb to Yersiniapestiwas determined by liquid dilution method.The gene expression profile of Yersinia pesti was performed after the exposure to Rhubarb at a concentration of 10×MIC for 30 minutes.The total RNA extracted and purified from Yersinia pesti Was reversely transfected to cDNA and labeled by Cy3-Cy5 dye.The labeled probes were hybridized to the microarray anti the results were obtained by a laser scanner and the microarray data was confirmed by real-time quantitative RT-PCR.Results The platform of the DNA microarray-based bacteria transcriptional profile was established.A total of 498 genes of Yersinia pesti changed significantly in response to Rhubarb.Among them.358 genes were up-regulated,140 down-reguated.Conclusions The whole genome DNA microarray can be used in the studying of molecular anti-Yersinia pesti mechanism of Rhubarb.

Global gene expression of berberine against Yersiniapestis in vitro / 中国地方病学杂志

Objective To investigate the antibacterial molecular mechanism of Traditional Chinese Medicine Coptis rhizome against Yersinia pestis(Y.pestis).Methods The method based on whole genome DNA micrnarray of Y.pestis was used.The minimal inhibition concentration(MIC)of berberine to Y.pestis was determined with liquid dilution method.Then gene expression profile of Y.pestis was performed after exposed to berberine at the concentration of 10×MIC for 30 minutes.Total RNA extracted and purified from Y.pestis and reverse-transcribed to cDNA,then labeled by Cy-dye.Finally,the labeled probes were hybridized to the microarray and the results were obtained by a laser scanner and analyzed by the SAM software.Results The gene expression profile data revealed that the response of Y.pestis to berberine was a global phenomenon.A total of 360 genes changed significantly.Among them,333 genes were up-regulated,27 down-regulated.These differentially expressed genes were further classified into 24 different functional categories based on the genomie annotation of Y.pestis CO92,in which the number of mainly related genes were 83,75 and 48,including cell envelop,unkown,transport/binding proteins functions.The 40 genes related to the metabolism were upregulated,which was a remarkable change.Conclusion Our results have revealed the general gene expression changes of Y.pestis in response to berberine and demonstrated the antibacterial molecular mechanism of the Coptis rhizome.The major mechanism of Y.pestis in response to berberine is the upregulation of genes related to the metabolism.