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Objective To evaluate the diagnostic value of serum M-type phospholipase A2 receptor(PLA2R) antibody detection for the diagnosis of idiopathic membranous nephropathy(IMN) by meta analysis.Methods By searching the databases of PubMed,Emabse,Wanfang and CNKI from inception to May,2017,all the literatures referred to serum PLA2R antibody for the diagnosis of IMN in both English and Chinese were reviewed and selected according to the inclusion and exclusion criteria.QUADAS was used to assess the quality of eligible studies.Meta-disc 1.4 was used to analyze heterogeneity and pooled effectsize and Stata 12.0 was used to analyze publication bias.Results A total of 20 studies with high quality were included.Heterogeneity test indicated there was no threshold effect.The pooled sensitivity was 0.69 (95 ％ CI:0.67 to 0.72),the pooled specificity was 0.97 (95 ％ CI:0.96 to 0.98) and the summary area under curve was 0.880.Sensitivity analysis indicated that the result was stable.Deek's funnel plot indicated there was no publication bias.Conclusion The sensitivity of detection of serum PLA2R antibody was acceptable for the diagnosis of IMN with high specificity,so more attention on PLA2R antibody should be paid in the clinical practice.
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Objective To construct a mutant strain of Streptococcus mutans ( S.mutans ) with clpC-deletion and to investigate the role of clpC gene in genetic competence.Methods The fragment of clpC gene and the kanamycin resistant cassette flanked by two loxP sites were amplified by PCR.The purified fragment of clpC gene was cloned into pMD-19T simple vector to construct pCKX1.The pCKX1 vector was digested with ClaⅠ/EcoRⅠ, then blunted and introduced into lox71-KMR-lox66 to obtain pCKX2 vector via homologous recombination.The pCKX2 vector was linearized with SalⅠ and transformed into S.mutans UA159 strain.The positive strains constructed via homologous recombination were screened with kanamycin and transformed with the thermosensitive plasmid pCrePA.The KMR cassette was excised after incubating at 30℃ for 48 hours.Then the pCrePA plasmid was removed after overnight incubating at 37℃for the prepara-tion of clpC-deletion mutant.Total RNA were extracted from the S.mutans UA159 strain and the clpC-dele-tion mutant strain respectively, and then reverse transcribed into first strand cDNA.The target gene frag-ments were amplified by RT-PCR and analyzed by the agarose gel electrophoresis and sequencing.After be-ing verified by PCR and sequencing, the S.mutans UA159 strain and the clpC-deletion mutant strain were re-spectively transformed with E.coli-S.mutans shuttle vector pDL276 to observe the competence development induced by the competence-stimulating peptide (CSP).Results The PCR and sequencing results showed that the pCKX2 vector and the mutant strain with clpC-deletion were constructed successfully via homologous recombination.No clpC gene was detected in the clpC-deletion mutant as indicated by RT-PCR analysis.The formation of competent clpC-deletion mutant was delayed and the competence state was prolonged as com-pared with its parent strains.Conclusion The clpC gene negatively regulated the formation of competent S.mutans.
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Objective To investigate the genotype and epidemiology of plasmid‐mediated AmpC β‐lactamases produced by the clinical strains of Escherichia coli and Klebsiella pneumoniae .Methods A total of 176 clinical nonrepetitive cefoxitin non‐sensitivity isolates of Escherichia coli and Klebsiella pneumoniae was collected from July 2011 to August 2012 .Polymerase chain reaction (PCR) for AmpC enzyme gene amplification and DNA sequencing were carried out for genotype of AmpC beta‐lactamases .Results The results of PCR showed that the positive rate of ampC of the 176 strains of Escherichia coli and Klebsiella pneumoniae AmpC was 18 .2% ,mainly DHA type ,counting for 59 .4% ,CIT counting for 37 .5% ,EBC counting for 3 .1% .The positive rate of ampC of Escherichia coli was 11 .4% ,mainly CIT type ,counting for 77 .8% ,the positive rates of DHA type and EBC type both were 11 .1% .The positive rate of ampC of Klebsiella pneumoniae were 23 .7% ,mainly DHA type ,counting for 78 .3% ,CIT type count‐ing for 21 .7% .The results of DNA sequencing showed that there were 18 strains DHA‐1 type and 1 strain ampC gene type of Morganella morganii in DHA type strains ,the concordance rate was 97 .0% ,10 CIT type strains was CMY‐2 type ,1 strain was CMY‐42 ,one strain was CMY‐4 type ,EBC type was ampC gene type of Enterobacter cloacae ,the concordance rate was 99 .0% .A total of 32 strains of gene sequencing were registered as KJ127248 - KJ127279 in GenBank .Conclusion The main genotypes of plasmid‐mediated ampC enzyme produced by Escherichia coli and Klebsiella pneumoniae were CMY‐2 and DHA‐1 respectively .
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Objective: To investigate the gene frequency of HLA-B* 5801 in the population of Chinese Minnan region.Methods:In this study,we enrolled 178 patients requiring allopurinol therapy( including 40 patients with gout,89 patients with hyperuricemia and 49 patients with gouty arthritis) and 100 healthy people.We isolated genomic DNA from their blood and screened for HLA-B*5801 with both PCR and gene sequencing.Results:We found 22%patients and 16%healthy people with HLA-B*5801.The frequencies of HLA-B*5801 in patients and healthy people are 0.13 and 0.09,respectively.The results from PCR and gene sequencing were consistent.Conclusion:The frequency of HLA-B*5801 in the population of Chinese Minnan region is relatively high.Therefore,it is necessary to screen for HLA-B*5801 in allopurinol users before taking the medicine.
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Objective To investigate the staphylococcal chromosomal cassette mec (SCCmec)genotypes and molecular epidemi-ology of hospital-acquired MRSA.Methods A total of 26 non-duplicate MRSA isolates with the same resistant pattern were studied.SCCmec genotyping was analyzed by multiplex PCR.Repetitive element polymerase chain reaction (Rep-PCR)tech-nique was used to analyze the homology between these strains based on the DiversiLab system.Results The most common geno-type of these MRSA strains was SCCmec-III (84.6%).Two strains belonged to SCCmec-II and 1 SCCmec-IV.SCCmec-I strain was not identified.Based on the results of DiversiLab analysis,these MRSA strains were classified into 10 groups.The genetic similarity ranged from 40% to 100% among these SCCmec types.The two strains of SCCmec-II belonged to the same subtype.The similarity coefficient was higher than 90% for one strain of SCCmec-III subtype 1.The 4 strains of SCCmec-III subtype 3 were grouped into the same set with a similarity coefficient of > 95%.The MRSA strains of SCCmec-III subtype 2 was divided into 5 groups (similarity co-efficient > 90%).Conclusions SCCmec-III is the major genotype of MRSA isolates in our hospital.MRSA strains may spread in some wards.Clinicians and infection control department should pay close attention to this issue.
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Objective To investigate and analyze the double-disk inhibiting synergy test for detecting AmpC β-lactamase pro-duced by Klebsiella pneumoniae and to evaluate its application value in clinical laboratory.Methods The cefoxitin disk agar diffu-sion method,cefoxitin three-dimensional method,double-disk inhibiting synergy test and drug resistance gene multiplex PCR assay were adopted to detect the clinically isolated bacterial strains.Results Among 137 clinically isolated strains of Klebsiella pneumoni-ae,22 strains were insensitive to cefoxitin and 11 strains were positive by the three-dimensional method;in the double-disk inhibiting synergy test,18 strains were positive for the FOX/FOX+PBA group and 11 strains were positive for the CTT/CTT+PBA group respectively;in the multiplex PCR assay,19 strains were positive.The coincidence rate of the cefoxitin three-dimensional method and multiplex PCR methods was 47.4%(9/19),in the double-disk inhibiting synergy test,the coincidence rate of the positive re-sults in the CTT/CTT+PBA group and the multiplex PCR methods was 57.9%(11/19);the coincidence rate of the FOX/FOX+PBA group and multiplex PCR methods was 94.7%(18/19).Conclusion The double-disk inhibiting synergy test is simple with highly accurate results,in which the FOX/FOX+PBA double-disk synergy test could be applied to detect AmpC β-lactamase pro-duced by clinical isolates of Klebsiella pneumoniae.
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Objective To investigate the prevalence of qepA, quinolone efflux protein, among 41 unique clinical strains of K. pneumoniae producing ESBLs and to study the qepA-bearing isolates using the Diversilab system. Methods Identification and antimicrobial susceptibility were performed by Vitek-2 Compact System. Screening of qepA was carried out by PCR amplification. The NCBI BLAST program was utilized for sequence comparisons. qnr-bearing strains was evaluated by the Repetitive-sequence-based PCR(Rep-PCR) employing the Diversilab system. And the existence of rmtB was detected among these qepA contained isolates. Results qepA were detected in 5 isolates( 12.2% ). The Rep-PCR profiles produced by the Diversilab system showed that 2/5 of isolates were indistinguishable. And 60% of qepA-positive isolates were detected to harbor rmtB gene. Conclusion The data suggest the emergence of qepA-borne K. pneumoniae.