[Abstract] Objective To evaluate the effect of Mycobacterium tuberculosis Direct Assay (MTD) for rapid detecting Mycobacterium tuberculosis rRNA and Multi-locus PCR for M.bovis BCG strain typing in patients with suspected extra-pulmonary tuberculosis.Methods From June 2010 to December 2011,47 children and 75 adult patients with suspected extra-pulmonary tuberculosis in Shanghai public health clinical center were recruited.Also 48 non-tuberculosis patients were taken as a negative control.Clinical specimens from these patients were collected.Acid fast stain,solid culture,liquid culture,and MTD were used to detect all clinical specimens simultaneously.Screen tuberculosis strains of the culture isolates by MPT64 antigen assay and use Multi-locus PCR for the BCG strain genotyping of the isolates without MPT64 antigen.SPSS16.0 was used to analyse the results.Results The sensitivity for acid fast stain,solid culture,liquid culture and MTD test was 10.7％ (13/122),11.5％ (14/122),16.4％ (20/122) and 37.7％ (46/122),respectively.And the specificity of MTD was 100.0％.Six clinical isolates from children were identified as BCG by Multi-locus PCR typing,the same with chemical tests.Conclusions The MTD assay and the MGIT960 liquid culture are effective and reliable method for diagnosing extra-pulmonary tuberculosis.And Multi-locus PCR can be assisted for the early diagnosis of extra-pulmonary tuberculosis patients with suspected BCG infection.

Objective To explore the influence of the scores and weights of the regular grade on the evaluation of students' learning effect.Method To compare the impact of the regular grade before and after adjustment on the total mark,analyze the problems exposed during scoring and search for the solutions according to Medical Microbiology results of four grades including Grade 2010 to 2013.SPSS 13.0 software was used for statistical analysis and Pearson method was used for correlation analysis and theory achievement scores.Results The regular grade of four grades scored highly,with the average (95.00 ± 3.80),(96.00 ± 4.55),(95.00 ± 2.84) and (95.00 ±-2.82) respectively.What was more,it had randomness.The correlation coefficient between regular grade and total mark were 0.069,0.149,0.984 and 0.285 respectively.The regular grade of Grade 2010 was the same as Grade 2013 and the theoretical score of Grade 2013 was 4 points lower than Grade 2010(71 vs.75),however the total mark of Grade 2013 was 1 point higher than Grade 2010 (80 vs.79),which showed the more the regular grade weights,the greater it impacted on the total mark.Conclusion The appropriate score and weight of the regular grade is important to evaluate the students' learning effect objectively.

Infection is one of the common complications of stroke. It can seriously affect the prognosis of patients. Poststroke infection is closely associated with immune system imbalance, while the excessive activation of sympathetic nerve is an important factor of the occurrence of immunosuppression after stroke. The sympathetic nerve regulates immune cels primarily via β2 adrenergic receptors on the surface of the immune cels. There is evidence to show that β2 adrenergic receptor mediated immune function enhances rather than inhibits under certain conditions, but its specific molecular mechanism is unclear. This article reviews the molecular mechanisms of β2 adrenergic signaling pathway in regulation of inflammation after stroke.

Objective To evaluate antimicrobial resistance and antimicrobial resistance mechanisms of Enterococcus faecalis (E.faecalis)to linezolid (LNZ),and provide basis for clinical rational drug use.Methods Twelve E.faecalis strains isolated from sputum of patients who received LNZ therapy in a hospital between January 2012 and January 2013 were collected.The minimum inhibitory concentrations (MICs)of antimicrobial agents were de-termined by agar dilution method,23S rRNA V region gene of E.faecalis was amplified by polymerase chain reac-tion,the amplified products were sequenced.Results Of 1 2 isolates,2 were intermediate strains and 1 0 sensitive strains.The G2576U mutation was detected in 2 intermediate strains,1 of which was also detected G2424U muta-tion;the variations were not detected in 10 sensitive strains.C2424U and G2576U mutation existed in R1 and R4 region respectively.Conclusion 23S rRNA V region gene mutations are found in the intermediate strains of E.faecalis.Change in MIC values of linezolid should be paid close attention in clinical use.

OBJECTIVE To determine the prevalence of gene qnrA in clinical isolates of Enterobacteriaceae,phenotypes of drug resistance and their molecular mechanisms.METHODS Totally 332 isolates of Enterobacteriaceae from Shenzhen City from 2003 to 2004 were screened for the presence of qnrA by PCR.The gyrA,and parC genes the genes,coding ESBLs and AmpC were amplified and sequenced.K-B method,the international standard plate dilute method and E-test were used to detect MIC of the isolates with qnrA.ESBLs were distinguished by the phenotypic confirmatory test.RESULTS The incidence of qnrA in clinical isolates was 3.9%,the highest incidence of 15.6% occurred in Enterobacter cloacae.The clinical isolates were multi-resistant.gyrA And parC mutation associated with quinolone resistance and ESBLs producing was confirmed in most of the isolates with qnrA.qnrA Was embedded in In37 or InX classified to Sul1 type class Ⅰ integrons.CONCLUSIONS Gene qnrA located in plasmids is an important mechanism mediated quinolone resistance in Enterobacteriaceae.The potential horizontal transferability and multiple resistance hereditary background in these isolates challenge the anti-infective therapy.

Objective This study was designed to examine the clinical characteristics of bloodstream infections (BSI) caused by Staphylococcus aureus in a teaching hospital and the risk factors for 30-day mortality.Methods A single center retrospective cohort study was conducted for all the patients with BSI caused by S.aureus between 2008 and 2015.The data of clinical features,microbiology,and 30-day mortality were collected from the database of electronic medical records.Results A total of 121 patients with S.aureus BSI were identified.The prevalence of methicillin-resistant S.aureus (MRSA) was 17.4％ (21/121).MRSA BSIs were significantly associated with old age (≥65 years) (P=0.026),hospital acquired infection (P=0.035),respiratory tract infection (P=0.001),polyinfection (P=0.005) and inappropriate initial antibiotic therapy (P=0.001) than methicillin-sensitive S.aureus (MS SA) BSIs.The 30-day mortality was 18.2％ (22/121).Both univariate and multivariate analysis suggested that solid tumor (OR,8.932,P=0.004) and septic shock (OR,56.721,P＜0.001) were independently associated with the 30-day mortality.Conclusions The present study confirms that solid tumor and septic shock are more important risk factors than MRSA in mortality of patients with S.aureus BSI.

Objective To study the homology characteristics of clinicaly isolated and colonized linezolid(LZD)-resistant Enterococcus faecalis (E.faecalis) strains from a patient.Methods Ten E.faecalis strains (2 were isolated from urine specimens and 8 were from stool specimens) isolated from a patient with pulmonary infection were performed antimicrobial susceptibility testing, homology of E.faecalis was determined by pulsed-field gel electrophoresis (PFGE).Results Before and after patients received LZD therapy, 2 E.faecalis strains isolated form urine specimens were both resistant to LZD (MICs: 8 mg/mL, 16 mg/mL, respectively), among 8 strains from stool specimens (6 were isolated before therapy, and 2 were isolated after therapy), LZD susceptible, intermediate, and resistant strains were 4, 2, and 2 respectively(MICs: 0.25-12 mg/mL).10 strains of E.faecalis were homologous by PFGE typing.Conclusion In this case, the detection of E.faecalis from urinary tract and intestinal tract is homologous, which suggested that LZD-resistant Enterococcus may be colonized in vivo for a long time, and may be shift to cause bacterial infection.

Objective To analyze the genomic evolution characteristics of pathogenicity islands (PAIs)in Deng strain of enteropathogenic Escherichia coli (E.coli,EPEC Deng).Methods EPEC Deng was isolated from infant stool specimen,serotypes were identified and antimicrobial susceptibility testing was performed;whole-genome se-quencing was performed by Illumina 2000 system,the locations of prophages(PPs)in the chromosome were detected using PHAST software,collinearity analysis was performed by MUMmer software,phylogenetic trees of homolo-gous gene were constructed in order to understand the evolutional rule of homology gene.PAIs prediction was per-formed using PAI finder software,the homologous evolutionary rule of PAIs core region(LEE)and core genes were clarified,genetic polymorphism was analyzed.Results The serotype of EPEC Deng strain was O119:H6,the strain was resistant to ciprofloxacin,levofloxacin,and ampicillin,but sensitive to other antimicrobial agents.The complete circular chromosome contained 5 025 482 bp with a GC content of 50.52 %,and the plasmid contained 207 564 bp with a GC content of 49.50%.A total of 17 PPs in the chromosomal genome were discovered,phyloge-netic trees analysis suggested that EPEC Deng strain was highly homologous with O26:H11 and O111 :H strains;PAIs and core genes were highly homologous with RDEC-1 and O26:H413/89-1 strains;genetic diversity analysis showed that the intimin (eae)and its receptor tir had high polymorphism,with the pi (π)value>0.10,the genes in type III secretion system was relatively stable.Conclusion The study clarified the genomic evolution characteris-tics of EPEC Deng genome and it’s PAIs,and is helpful for understanding genetic characteristics of native EPEC.

ObjectiveTo analyze the characterstics of phenotype and genotype of multidrug resistant tuberculosis (MDR-TB) and extensively drug resistant tuberculosis (XDR-TB) by molecular line probe assay and liquid culture with MGIT960.MethodsGenoType MTBDR Kits were used for identifying the types of the first-line and second-line antituberculosis drug resistant genes partly and BD MGIT960 was used for detecting the chug susceptibility.Results( 1 ) Out of 94 MDR-TB strains,the rate of drug resistant to EMB,AMK,OFX and MFX by BD MGIT960 assay were 36.2%,17.0%,54.3% and 55.3%,respectively.Among these isolates,13 were extensively drug resistant tuberculosis (XDR-TB).(2) Compared with MGIT960,the concordance rate of GenoType MTBDRplus was 86.2% and 95.7% respectively.Taking MGIT960 results as reference,the sensitivity of GenoType MTBDRsl detecting the susceptibility of EMB,AMK,OFX and MFX to 94 isolates were 47.1%,81.3%,94.1%,94.2%,respectively.The specificity were 75.0%,98.7%,90.7%,92.9%,respectively.(3) Among the rpoB mutation categories,S531L accounts for most.MTB resistant to IFN caused by the mutation of katG chiefly and the S315T1 was in the majority.The gyrA mutation sites located at the ninety-fourth codon most.Out of 94 strains,23 were mixed with 2 kindsof Mycobacterium tuberculosis at least and 7 were undetectable mutations.Conclusion Among the M/XDR-TB,the strains resistant to INH,RFP,AMK,OFX and MFX were caused most by the mutation of katG,rpoB,rrs and gyrA,respectively.The relationship between EMB and embB was not so clear relatively.As a fast detecting drug susceptibility test kit,GenoType MTBDR possess good sensitivity and specificity.So,it could be as an assistant method to guide the therapy on clinic.

Objective To investigate the relationship between the expression of ITGAV and the radiosensitivity of NSCLC cells. Methods The expression of ITGAV in NSCLC and its relationship to the prognosis of patients who received radiotherapy were analyzed using bioinformatics methods. Differences in radiosensitivity between radio-resistant cells and parent cells were verified by clone formation experiment, and the protein expression of ITGAV was detected by Western blot. The transfection efficiency of si-ITGAV was determined by Western blot and qRT-PCR analyses. The best ITGAV interference sequence was selected to transfect A549R and H1299R cells. Clone formation experiment and flow cytometry were used to detect clone formation, apoptosis and cell cycle of A549R and H1299R cells. Results The expression of ITGAV in NSCLC tissues was significantly higher than that in normal tissues (P<0.05), and NSCLC patients with high ITGAV expression had poor prognosis. The clonogenic ability of the si-ITGAV group was significantly lower than that of the negative control group at 4, 6, 8Gy irradiation (all P<0.05). After 6 Gy irradiation, the apoptosis of the si-ITGAV group was increased (P_H1299R<0.0001, P_A549R=0.0002), the proportion of G₂/M phase cells to A549-siITGAV and H1299R-siITGAV cells was higher than that in the negative control group (P_H1299R<0.0001, P_A549R=0.0007). Conclusion Interfering with ITGAV expression can increase the radiosensitivity of NSCLC.