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Objective To discuss the application value of modified Hodge test(MHT) for screening carbapenemase-producing Enterobacteriaceae.Methods The 24 Enterobacteriaceae reduced susceptibility to carbapenems were detected by MHT.At the same time,polymerase chain reaction(PCR) was used to detect carbapenemase genes of KPC,NDM,IMP,SIM and VIM.PCR products were sequenced and the results were compared with the sequences of Gen Bank database.Comprehensive analysis the application value of MHT and PCR to detect carbapenemase.Results Among these 24 strains,13 stains appeared to produce carbapenemase by MHT,5 positive strains were found to carry carbapenemase genes by PCR.By comparing with the sequences of Gen Bank database 1 strain were confirmed to KPC-2 and 4 strains were confirmed to IMP-4.We found that 4 strains of Enterobacteriaceae,detected carbapenemase by MHT and PCR at the same time.9 strains of MHT were positive,but we couldn′t detect the carbapenemase genes.1 strain of MHT was negative,but carbapenemase gene was found in the strain.Conclusion The value of MHT to screen carbapenemase-producing Enterobacteriaceae is necessary to further study.
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Objective To investigate SCCmec types in clinical isolates of methicillin-resistant Staphylococcus epidermidis (MRSE) carrying psm-mec.Methods We collected 165 strains of Staphylococcus epidermidis identified by automated microbiological identification system and screened MRSE by PCR amplification of esp and mecA gene.Strains with psm-mec were identified by amplification of psm-mec,fudoh and p221 DNA fragment;mec,ccr and SCCmec typing was conducted by multiplex PCR assay.Results Among 138 strains of MRSE,29 strains were identified as MRSE with psm-mec,and the carrying rate was 17.58%.Results of mec and ccr typing by multiple PCR showed that MRSE with psm-mec carried Class A mec,but the ccr type had obvious diversity.Results of SCCmec typing showed that all strains with psm-mec belonged to type Ⅱ and/or Ⅲ SCCmec.Conclusion Clinical isolates of MRSE with psm-mec carry homologous type Ⅱ and/or Ⅲ SCCmec harboring Class A mec.
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Objective To know the contents and changes situation of trace elements among children aged 0-6 years old in Chengdu are‐a .Methods The BH5100T atomic absorption spectrometry was adopted to detect the levels of trace elements Cu ,Zn ,Ca ,Mg ,Fe in 786 children aged 0-6 years old undergoing the physical examination in our hospital from April 2015 to November 2015 .The detection results were statistically analyzed .Results The deficiency rates of Cu ,Zn ,Ca ,Mg and Fe in Chengdu area were 0 .4% ,5 .0% ,18 .1% ,9 .5% and 8 .3% respectively ,in which the deficiency rates of Ca in children aged <1 ,1 ,2 ,3 ,≥ 4 years old were 47 .4% ,27 .5% ,12 .6% ,9 .9% and 11 .9% respectively ,indicating that the Ca deficiency rate in children < 1 years old was higher .The Ca deficiency rate had statistical differ‐ence among different age groups(P<0 .05) ,and there were no statistically significant differences in the deficiency rates of several trace ele‐ments among different age groups of male and female children .Conclusion The abnormality rate of trace elements among children aged 0-6 years old in Chengdu area is higher ,in which the Ca deficiency rate is highest ,meanwhile the Mg and Fe were lack too .The trace element content in children is closely related with the feeding habit .The 0-6 years old children in this area should pay attention to the supplement of trace elements ,especially supplement of Ca ,meanw hile breastfeeding is advocated .
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Objective To investigate the SCCmec types of clinically isolated methicillin‐resistant Staphylococcus epidermidis (M RSE) .Methods Eighty‐four strains of clinically isolated Staphylococcus epidermidis identified by the fully automatic microbio‐logical identification system were collected and performed the MRSE identification by PCR for amplifying esp and mecA genes and SCCmec typing .Its distribution characteristics were analyzed .Results Esp gene was amplified in 84 strains and the detection rate of mecA was 76 .19% (64/84) ,in which the MRSE detection rates in blood ,sputum ,urine and wound secretion were 76 .8% , 68 .8% ,100% and 71 .4% respectively .The multiple PCR amplification displayed that among 64 strains of MRSE ,19 strains were SCCmec simple type ,in which 19 strains were SCCmec type Ⅰ and 3 strains were SCCmec type Ⅲ ;42 strains were SCCmec mixed type ,in which 2 strains were SCCmec mixed type Ⅰ and Ⅱ ,14 strains were SCCmec mixed type Ⅰ and Ⅲ ,12 strains were SCCmec mixed type Ⅰ ,Ⅱ and Ⅲ ,5 strains were SCCmec mixed type Ⅱ and Ⅲ ,a strains were and SCCmec mixed type Ⅲ and Ⅳ .Conclu‐sion The SCCmec type in clinically isolated MRSE shows obvious diversity and its majority is SCCmec mixed type .
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Objective To analyse the correlation between cytotoxic T-lymphocyte antigen-4(CTLA-4)gene polymorphism-318 T/C ,CT60 G/A and the susceptibility of hepatocellular carcinoma (HCC) .Methods Totally 277 cases of HCC and 306 healthy controls in our hospital from September 2012 to September 2014 were selected as the research subjects ,all subjects were Han nationality .The peripheral blood (5 mL) in each case was collected for separating serum ,the AFP level was detected by chemilunescent method ,the serum IL-2 ,IL-4 and TGF-β levels were detected by ELISA .Genomic DNA was extracted ,after PCR amplification ,the CTLA-4-318 T/C ,CT60 G/A gene polymorphism distributions were detected by the direct sequencing method . Results The CTLA-4-318 CC and CT60 AA genotypes all conformed to the Hardy-Weinberg equilibrium(P> 0 .05) .CTLA-4-318 CC and CT60 AA were related with the HCC risk decrease ,different genotypes of CTLA-4 CT60 G/A had obvious relation with serum AFP level(χ2 =12 .779 ,P=0 .012) .The serum IL-2 and IL-4 levels in the HCC patients carrying CTLA-4-318 T and CT60 G allele were significantly decreased ,while the TGF-βlevel was significantly increased ,moreover CTLA-4-318 had obvious relation with the HCC grading .Conclusion CTLA-4-318 TT could promote the occurrence and progression of HCC ,which might be related with the down-regulation of Th1/Th2 type cytokines ,and up-regulation of Th3 type cytokine .
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Objective To investigate the incidences, risk factors, genotypes and epidemiology of community-acquired blood stream infection caused by extended spectrum β-lactamases (ESBLs)-producing Escherichia coli and Klebsiella pneumonia strains and to analyze the sensitivity of those ESBLs producing strains to commonly used antibiotics. Methods Forty-two patients who were diagnosed with community-ac-quired blood stream infection caused by Escherichia coli or Klebsiella pneumonia strains in Sichuan Provincial People′s Hospital were recruited in this study. Disc diffusion method was used for the phenotypic confirmato-ry test of ESBLs. Agar dilution method was performed to measure the antimicrobial susceptibility of the ESBLs-producing strains to 13 clinically commonly used antibiotics. Genotypes of the ESBLs-producing strains were identified by polymerase chain reaction (PCR). Multilocus sequence typing (MLST) was used to analyze the epidemiology of ESBLs-producing strains. Logistic regression analysis was performed to analyze the risk factors for community-acquired blood stream infection. Results The ESBLs-producing Escherichia coli strains accounted for 56. 3% (18 / 32) and the ESBLs-producing Klebsiella pneumoniae strains accounted for 20% (2 / 10). All of the 20 ESBLs-producing strains were sensitive to imipenem, meropenem, ertapen-em, nitrofurantoin and moxalactam. The ESBLs-producing strains sensitive to amikacin, piperacillin-tazobactam and fosfomycin accounted for 95% , 90% and 85% , respectively. Drug resistance rates of the 20 strains to cefotaxime, levofloxacin, ciprofloxacin and cefepime were relatively high accounting for 100% , 80% , 80% and 75% , respectively. Among the 20 ESBLs-producing strains, 7 strains only carried the CTM gene, while the other 13 strains were all positive for two genotypes of ESBLs, mainly identified as TEM+CTM-M-14 and TEM+CTM-15 genotypes. The 18 Escherichia coli strains were classified into 10 ST types, most of which were ST131 type, followed by ST10 and ST38 types. This study indicated that malignant tumor might be a possible risk factor. Conclusion The prevalence of community-acquired blood stream infection caused by ESBLs-producing Escherichia coli strains was becoming increasingly serious. Malignant tumor might be the risk factor associated with the producing of ESBLs in Escherichia coli and Klebsiella pneumonia strains. TEM+CTX-M-14 was the predominant genotype of ESBLs-producing strains and the prevalent clone was ST131 type. Carbapenems and enzyme inhibitor compounds were ideal drugs for the treatment of commu-nity-acquired blood stream infection caused by ESBLs-producing Escherichia coli and Klebsiella pneumonia strains. This study was limited by the small sample size. Therefore, it is necessary to conduct further resear-ches based on a large number of samples.
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Objective To evaluate the diagnostic value of three tumor markers ,including alpha‐fetoprotein(AFP) ,golgi glyco‐protein 73(GP73)and tumor specific growth factor(TSGF) ,and significance of combined detection in diagnosis of primary liver cancer(PHC) .Methods Serum levels of AFP ,GP73 and TSGF were detected in 90 cases of patients with PHC(PHC group) ,52 cases of patients with liver metastasis(liver metastasis group) ,41 cases of patients with benign liver disease(benign liver disease group) ,and 55 cases of healthy individuals(healthy control group) .And clinical value of combined detection of AFP ,GP73 and TS‐GF for diagnosing PHC was analysed .Results The serum levels of AFP ,GP73 and TSGF were significantly higher than those in benign liver disease group and healthy control group ,the differences were statistically significant(P< 0 .05) .The specificity of AFP ,GP73 and TSGF in diagnosis of PHC was 79 .7% ,71 .6% and 83 .1% ,respectively .The sensitivity of AFP ,GP73 and TSGF in the diagnosis of PHC was 57 .8% ,74 .4% and 65 .6% ,respectively .The combined detection of AFP ,GP73 and TSGF improved the sensitivity for diagnosing PHC(96 .6% ) ,while the specificity of combined detection was decreased(68 .9% ) .And the diagnosis rates of PHC patients with negative AFP or low levels of AFP were increased when combined the three tumor markers . Conclusion Combined detection of AFP ,GP73 and TSGF as a significant indicator for diagnosing PHC could improve the diagnosis rate of PHC .
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Objective To investigate the genetic location of SCCmec-associated psm-mec in Staphylococcus hominis isolated from blood culture,and to lay a foundation for further functional studies of psm-mec in Staphylococcus hominis.Methods 25 strains of Staphylococcus hominis isolated from positive blood culture were collected.mecA and psm-mec gene were amplified by PCR,and the SCCmec types were determined by the results of multiplex PCR assay.For analyzing the genetic location characteristic of psm-mec in SCCmec,three pair special PCR primers were used to measure mecR1/psm-mec,psm-mec/xylR and fudoh respectively.Results There were 21 strains of methicillin-resistant Staphylococcus hominis and 4 strains of methicillin-sensitive Staphylococcus hominis. The positive rate of psm-mec gene in methicillin-resistant Staphylococcus hominis was 47.6%,and no psm-mec gene was found in methicillin-sensitive Staphylococcus hominis.Among psm-mec positive strains,2 strains belonged to SCCmecⅢ,5 strains belonged to SCCmecⅢ-like,and 3 strains belonged to new SCCmec types.All of the 10 psm-mec positive strains were mecR1/psm-mec,psm-mec/xylR and fudoh gene positive.Conclusion SCCmec-associated psm-mec extensively exists in methicillin-resistant Staphylococ-cus hominis isolated from positive blood culture,which distributes mainly in typical SCCmecⅢ,SCCmecⅢ-like and new SCCmec types and locates between mecR1 and xylR gene.
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Objective To study the clinical characteristics of acute leukemia(AL) patients with cross‐lineage antigen expression . Methods Patients were diagnosed and classified by morphology ,cytochemistry and immunology assay ,and prognostic acting factor were also analyzed .Results According to FAB standards ,acute myeloid leukemia(AML)‐M2 ,acute lymphocytic leukemia (ALL)‐L2 and no‐classified type were common in 320 patients with cross‐lineage antigen expression .The immunophenotype with B and my‐eloid mixed expression was the most common(176 cases) ,followed by cross expression of antigen T and myeloid(131 cases) ,and the co‐expression of B ,T and myeloid antigen was found in only 10 cases .In lymphoid antigenpositive AML(Ly+ AML) ,CD19 anti‐gen was the most common among B lineage ,CD7 was the most common in T lineage .In myeloid antigen positive ALL(My+ ALL) , CD33 was the most common myeloid antigen .Forty‐five cases were with mixed expression of myeloid antigen and CD56 expression . Correlation existed between CD7 and CD34(P< 0 .05) ,CD19 and CD34(P< 0 .05) .There were 9 patients with CD34 ,CD7 and CD19 co‐expression ,7 patients with CD34 ,CD7 and CD56 co‐express .In Ly+ AML patients ,23 cases were with recurrent chromo‐some abnormality ,including 11 cases with t(8 ;21)(q22 ;q22) ,RUNX1‐RUNX1T1 ,3 cases with t(15;17)(q22 ;q11‐12) ,PML/RAR ,6 cases with bone marrow eosinophilia inv(16)(p13 ;q22) ,CBF beta /MYH11 ,and 3 cases with t(9;11)(p22;q23) , MLLT3‐MLL .In My+ ALL ,15 patients were with recurrent chromosome abnormality ,including 9 cases of B‐ALL with t(9;22) (q34 ;q11 .2) ,BCR‐ABL1 ,3 cases of B‐ALL with t(v ;11q23) ,MLL rearrangement ,and 3 cases of T‐ALL with 14q11 .2 .Among the presence of reproducible chromosomal abnormalities in AL ,the antigen expression of mistranslation was still with a certain fea‐ture:Ly+ AML patients often mistranslated CD19 ,CD56 ,CD2 ,and My+ ALL patients often mistranslated CD13 and CD33 .Com‐pared with the lymphoid antigennegative AML(Ly - ALL) group ,CD7+ AML group ,CD19+ AML group and CD56+ AML group had significant difference in survival curves(with P value of 0 .01 ,0 .02 and 0 .02) .There was no significant difference in survival curves between myeloid antigen negative ALL(My -ALL) group and CD13/33+ ALL group(P<0 .05) .CD7 was also positive com‐monly(53 cases) and related with CD34(P<0 .05) .So it significantly influenced the prognosis .If patients were with co‐expression of CD34 ,CD7 and CD19 ,the prognosis could be worse .Conclusion AL with cross‐lineage antigen expression might be a special type and confirmed by immunotype .Furthermore ,expression types of differentiation antigen could be critical for prognosis and sur‐vival .
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Objective To investigate the correlation between infertility and TORCH infections ,analyse the possible influence factors .Methods TORCH infections of 2343 cases of pregnant women and 1356 cases of infertility women were detected by chemi‐luminescence method ,the positive rates of TORCH‐IgM ,IgG were compared .Results RV ,HSV infections of infertility women were higher ,mainly in 30 -34 years group .TORCH infections of infertility women among seasons were of significant difference (P<0 .05) .TORCH infections of infertility women have correlations with schooling levels ,source of family ,and history of expo‐sure to animals (P<0 .05) .Conclusion The less education ,rural aera ,and history of exposure to animals were high risk factors of TORCH infections ,so screening for TORCH infections of infertility women is very necessary .
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Objective To construct mutant strains of methicillin resistant Staphylococcus epidermi-dis (MRSE) with psm-mec gene deletion and to investigate the function of psm-mec gene.Methods The drug sensitivity test and DNA sequence analysis were performed to screen out the tetracycline and chloram -phenicol sensitive clinical strains of MRSE , whose upstream and downstream sequences of psm-mec gene were identical to those of the Staphylococcus epidermidis reference strain RP62A.The recombinant plasmid pBT2-Δpsm-mec was constructed by using the fusion PCR and a temperature sensitive shuttle plasmid .After being identified , the plasmid was transformed into the Staphylococcus aureus RN4220 strain by electropora-tion, and then transformed into the selected clinical isolates of MRSE .The mutant strains of MRSE with psm-mec deletion were screened out and identified after homologous recombination .The differences in biofilm formation between the mutant and wild-type strains were analyzed for further elucidation the relationships be-tween the psm-mec gene and biofilm formation in MRSE strains .Results Three clinical MRSE isolates for the construction of mutant strains with psm-mec gene deletion were screened out and identified by using drug sensitivity test and sequence alignment analysis .The mutants constructed via homogenous recombination were screened out and identified .Compared with the corresponding wild-type strains, the three mutants with psm-mec gene deletion showed significantly decreased ability of biofilm formation , demonstrating that the psm-mec genes strains induced the biofilm formation of MRSE .Conclusion The Δpsm-mec mutant strains were successfully constructed .The psm-mec gene played an important role in the biofilm formation of Staphy-lococcus epidermdis.
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Objective To evaluate the reliability of gas sampling from the distal end of the tracheal tube for partial pressure of end-tidal CO2 (PETCO2) monitoring in neonates.Methods A total of 50 fullterm neonates,scheduled for elective abdominal surgery under general anesthesia,aged 1-28 days,weighing 2.55-4.00 kg,of ASA physical status Ⅰ or Ⅱ,were randomly divided into 2 groups (n =25 each) using a random number table:gas samples collected from proximal end of tracheal tube group (group P) and gas samples collected from distal end of tracheal tube group (group D).Epidural catheters of 1 mm in external diameter were used.One end of the catheter was connected to a tube for carbon dioxide sampling,and the other end was inserted into the endotracheal tube and advanced toward the distal hole of the tube.At 15 min of mechanical ventilation,blood samples were collected from the radial artery for record of PETCO2 and for blood gas analysis.Consistency test was performed between PETCO2 and partial pressure of arterial CO2 (PaCO2).Results PET CO2 was significantly lower than PaCO2 in the two groups.There was no significant difference in PaCO2between the two groups.PETCO2 was significantly higher in group D than in group P.Kappa was significantly higher in group D than in group P.Conclusion Gas sampling from the distal end of the tracheal tube is more reliable than gas sampling from the proximal end in monitoring PETCO2 in the neonates.
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Objective To explore the establishment of peptide mapping database of Candida albicans ,laying the foundation for rapid diagnosis of Candida albicans infection .Methods 96 Candida albicans were collected clinically ,and its DNA was extracted . Polymerase chain reaction(PCR) was used to amplify the ITS1-5 .8S-ITS2 gene fragments and restriction endonucleases were a-dopted to identify them .Surface enhanced laser desorption ionization-time of flight-mass spectrometry(SELDI-TOF-MS) instrument was applied to detect the Candida albicans peptide mapping ,and Ciphergen ProteinChip software was used to collect data automati-cally .The established peptide mapping database was verified by confirmed Candida .Results According to restriction fragment length polymorphism analysis ,96 strains were confirmed as Candida albicans .15 peptide peaks were captured by SELDI-TOF-MS chips .Five peptide peaks of them with stable expression were screened out ,and the similarity analysis software was used to estab-lish peptide mapping database of Candida albicans .More than 95% of similarity was found between peptide mapping of Candida albicans and established database ,while less than 50% was found between peptide mapping of other Candida species and database . Conclusion The establishment of peptide mapping database of Candida albicans provides a theoretical basis for the rapid diagnosis of Candida albicans infection .
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Objective To investigate the comparability of the activity detection of 6 common serum enzymes by different bio-chemical detecting systems at the same laboratory to provide the basis for realizing the traceability and comparability of serum en-zyme detection.Methods The detection system consisted of the Hitachi 008 biochemical analyzer,and original reagents,C-fas cali-brator and controller of Roche was taken as the reference system X(comparison method)and the detection system consisted of the ABBOTT ARCHITECT C16000 biochemical analyzer,reagents and calibrator of Zhongsheng,and controller of BIO-RAD was taken as the detecting systemY (laboratory method),which were used to detect the accuracy and precision of fresh serum enzymes inclu-ding ALT,AST,ALP,GGT,LDH and CK according to the NCCLS document EP9-A2.Then the enzyme activity results detected by the Y and X methods were compared and the relative error(SE%)was calculated.The comparability of the results detected by these two kinds of different detection systems was judged with 1/2 of allowable error in the external quality assessment stipulated by CLIA′88 as the standard.Results The accuracy and precision of the activity detection results of 6 enzymes by the Hitachi 008 and ARCHITECT C16000 biochemical analyzers all conformed to the requirements and the systematic error was clinically acceptable. Conclusion In measuring same test item by two or more detection systems,the method comparability and the bias assessment should be performed for ensuring the accuracy and comparability of the detection results.
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Objective To evaluate the main performance of ABBOTT ARCHITECT C160000 biochemistry analyzer,and to judge whether the performance meets the laboratory requirement.Methods According to the clinical laboratory management meth-od and the requirement of accreditation of national laboratory,the precision,accuracy and linearity of the 17 test items(Urea,Cre, UA,Glu,etc.)were analyzed by the CLSI EP5-A2 document,CLSI EP9-A2 document and CLSI EP6-P document;the quotative ref-erence ranges of the 17 test items were verified.Results The coefficient of variation(CV)in within-batch precision of Urea,Cre, UA,Glu,etc.was ≤1/4 CLIA′88 standard and CV in the between-batch precision ≤1/3CLIA′88 standard;in the accuracy test,the relative bias of the 17 test items≤1/2CLIA′88 standard;the linearity of the 17 items was good(r2 >0.95);the cited reference range of various detection items was suitable.Conclusion The performance of the ABBOTT ARCHITECT C160000 automatic biochem-istry analyzer meets the laboratory demand.
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Objective To investigate the mechanism of one carbapenems resistant Raoultella planticola( R.planticola) isolate.Methods This is an experimental study.R.planticola was isolated from a patient′s drainage fluid from orthopedic department in November 2010 in Sichuan Provincial People′s Hospital.Minimum inhibitory concentration of R.planticola to 13 antibiotics was determined by using the agar dilution method.Modified Hodge test was used to detect carbapenemase .EDTA synergistic test was performed to research metallo-beta-lactamase.The genes coded the β-lactamase were amplified by polymerase chain reaction ( PCR ) , including class A carbapenemase ( KPC ) , class B carbapenemases (NDM, IMP, VIM, SIM), extended spectrum beta-lactamases[ESBL(CTX, TEM, SHV)], and AmpCβ-lactamases ( FOX, EBC, ACC, DHA, CIT, MOX).Results The susceptibility test showed that R.planticola was resistant to 9 antibiotics.MIC value of meropenem for R.planticola was up to 32 mg/L.R.planticola kept intermediary to imipenem , whereas it was susceptible to cefepime , amikacin and polymyxin B.Modified Hodge test and EDTA synergistic test were positive in R.planticola.Class B carbapenemase (IMP) gene and two extended spectrum β-lactamases(CTX, SHV) genes were positive by PCR.The genes were conformed as IMP-4, CTX-M3 and SHV-12 by sequencing and compared with GenBank.Other resistant genes were negative.Conclusion IMP-4 was identified in R.planticola, the combined produce IMP-4 and ESBLs might be the main mechanism of R.planticola resistant to carbapenems.
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Objective To investigate the clinical value of serum iron(Fe),total iron binding capacity(TIBC),serum ferritin(SF), folic acid(FA)and vitamin 12(ViB12 )in the diagnosis and treatment of chronic renal failure(CRF).Methods Fasting blood sam-ples were collected from 72 patients with CRF and 83 normal controls.Then the serum SF,ViB12 and FA contents were measured by the ARCHITECT i2000SR fully automatic chemiluminescence immunoassay analyzer;serum Fe and TIBC were detected by the VITORS FS 5.1 dry biochemical analyzer;RBC,HGB,HCT and MCV were analyzed by the Mindray BC-6800 complete automated blood counter.The detection results were performed the statistical analysis by the SPSS16.0 software.Results The levels of TIBC,RBC,HGB and HCT in the CRF patients were significantly lower than those in the control group(P 0.05);the FA level in the female patients was lower than that in the control group,but which in the male patients had no statistical differences compared with the control group(P >0.05).Conclusion The indexes of anemia associat-ed metabolin in the CRF patients can provide certain reference value for the diagnosis and treatment of chronic renal fail and has cer-tain guidance significance for correcting anemia caused by renal insufficiency.
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Objective To establish protein fingerprints of common bacteria in clinics and to lay a foundation for rapid identification of bacteria.Methods Strains of Escherichia coli,Klebsiella pneumoniae,Pseudomonas aeruginosa and Staphylococcus aureus were detected by surface enhanced laser desorption and ionization time-of-flight mass spectrometry (SELDI-TOF MS).Stable expression protein peaks were screened and the data was input into the self-constructed Fingerwave software for identification of target bacteria by protein fingerprint comparison.Two hundred and fifty-six clinical isolates,including E.coli,K.pneumoniae,P.aeruginosa and S.aureus were detected and the data was compared with constructed database to evaluate its diagnostic value.Results The protein fingerprints including four common bacteia was used to identify the target bacteria with identification rate of 93.1％ (54/58) for E.coli,87.2％ (75/86) for K.pneumoniae,96.2％ (60/63) for P.aeruginosa and 96.2％ (51/53) for S.aureus,respectively.Conclusion Common bacteria can be rapidly identified by using the protein fingerprint comparison,which provides a powerful tool for bacterial identification.
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Objective To establish protein fingerprinting identification model of Pseudomonas aeruginosa (P. aeruginosa) and to lay a foundation for rapid identification of P. aeruginosa by proteinchip golden array. Methods Sixty-four P. aeruginosa and one hundred and ninety-nine control bacteria identified in our laboratory were collected and divided into training and testing group. Surface enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF-MS) and proteinchip golden array were used to detect the protein profiling of the bacteria. Data were automatically collected by Ciphergen Proteinchip Software and protein markers of P. aeruginosa were screened by BioMarker Wizard Software. Classification tree model was developed and validated by BioMarker Patterns Software. The model was blindly tested with twenty-nine P. aeruginosa and sixty-four control bacteria. Results Eighty protein peaks were detected between 3000 and 20 000, among which fifty-eight ones showed significantly difference between P. aeruginosa and the control bacteria (P＜0.01). By BioMarker Patterns Software, one protein peak ( M/Z at 14 045.2) was chosen to develop a classification tree model. The results exhibited with sensitivity of 96. 55% and specificity of 100%. Conclusion Proteinchip golden array has the potential for rapid identification of P. aeruginosa.
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Objective To evaluate the effect of various sampling errors on ELISA test results. Methods Standard sample volume,standard sample volume reducing 1,2,3,4 μL or adding 1, 2,3 μL were respectively pipetted into the wells of a microplate,follwed by routine operation of ELISA test. Then the influence of various sampling errors was analyzed on ELISA test results of HBsAg, HCV and TP. Results S/CO value was increased with the increase of sample volume. The statistical difference of mean S/CO value of HBsAg and TP was only found between sample volume adding 3 μL group and control group(P<0.05). For HCV result, there were significant differences between standard sample volume adding 2,3μL or reducing 3,4μL groups and control group(P<0.05), while no obvious differences were found in the other groups(P>0.05). The difference of mean positive rate between ex-perimental groups and control group showed an increasing tendency with the reduction of sample vol-ume,and significant differences in HBsAg, HCV and TP results were also found between sample vol-ume increase groups and reduction groups(P<0.05). Conclusion Various sampling errors influence ELISA test results to different degrees,and the extent increases with the reduction of standard sample volume.