1.Application of Raman spectroscopy in the rapid detection of pathogenic microorganisms
Jinying DONG ; Yang ZHANG ; Hao LIU ; Jiaoqi HUANG ; Wei LIU ; Junfu HUANG ; Yuzhong LI ; Weiling FU
Chinese Journal of Laboratory Medicine 2018;41(1):5-8
With the rapid development of instrument technology , Raman spectrometer has become one of the fastest growing type of instrument in the molecular spectroscopy . In recent years , Raman spectrometer gradually emerging in the application in the domain of biology and medicine , Raman spectroscopy technology appears new development constantly in the rapid identification and classification of microorganisms because of its rapid , efficient, sensitive, noninvasive, repeatability and other unique advantages.This article describes its application in the rapid detection of bacteria , viruses and other microorganisms , and also prospects for the application of Raman spectroscopy in future clinical work .
2.Application of terahertz spectroscopy in the detection of cell and tissue
Hao LIU ; Yang ZHANG ; Jinying DONG ; Jiaoqi HUANG ; Wei LIU ; Junfu HUANG ; Yuzhong LI ; Weiling FU
Chinese Journal of Laboratory Medicine 2018;41(5):348-351
As a novel,label-free and non-invasive detection modality,terahertz(THz,1THz=1012 Hz)spectroscopy has been widely used in various areas.For instance,in the biomedical field,it has great potentials to provide real-time scanning of living cells and tissues due to its unique advantages.Significant achievements have been reached in cell detection, related to bacterial identification, cancer cell characterization and blood cell detection.In tissue detection, the THz spectroscopy can be used to provide real-time scanning of living tissues and fast diagnosis.Furthermore, a single system which integrated THz spectroscopy and THz imaging would be able to collect information more sensitive and comprehensive. However,the clinical adaption of THz spectroscopy is still a controversial issue attributed to some intrinsic limitations and technical bottlenecks.In this article, both the application of THz spectroscopy in cell and tissue detection and the existing challenges and strategies to accelerate clinical applications were reviewed comprehensively.
3.Analysis of distribution of 15249 strains of nosocomial infection pathogens and drug resistance
Zhiyong LIU ; Juan YUAN ; Mei YANG ; Hongying YUAN ; Bo ZHANG ; Junfu HUANG ; Weiling FU
International Journal of Laboratory Medicine 2017;38(23):3252-3256
Objective To monitor the distribution of pathogens and the drug resistance of inpatients in Southwest Hospital in ChongQing ,and to analyze the prevalence of pathogens in various departments .Methods A total of 15249 pathogens cultured from clinical specimens in our hospital in 2016 and the antimicrobial susceptibility testing results were retrospectively analyzed .The anti-microbial susceptibility testing was carried out by using the paper diffusion method (K-B) or the automated instrument method (MIC) .The data were analyzed by WHONET5 .5 software according to the standard of CLSI2017-M100 .Results Compared with 2015 ,a total of 15249 pathogenic microorganisms were isolated from the hospital in 2016 ,among which 9742 were Gram-negative bacteria ,down 11 .45% and 4188 were Gram-positive bacteria ,up 15 .34% and 1319 were fungi ,down 11 .48% .Top five depart-ments which collected most microbiological culture specimen were Burn ,Pediatric ,ICU ,Hepatobiliary surgery ,Neurosurgery .The main specimen type of culture was sputum ,accounting for 27 .28% ,followed by blood ,wound secretion ,urine ,abdominal fluid .The first five pathogens were Klebsiella pneumoniae ,Acinetobacter baumannii ,Escherichia coli ,Staphylococcus aureus ,Pseudomonas aeruginosa .Conclusion Gram-negative bacteria are mainly infected organisms in our hospital .However ,Gram-positive bacteria are also important pathogens .Antibiotics should be selected according to the results of antimicrobial susceptibility testing .The distribu-tion of pathogens and the changes of drug sensitivity should be emphasized ,which can provide an effective theoretical basis for treat-ment .
4.Methicillin-resistant Staphylococcus aureus SCCmec parting and resistance analysis
Yu WU ; Guiyu WANG ; Yao YU ; Li XU ; Junfu HUANG
International Journal of Laboratory Medicine 2016;37(4):455-456,458
Objective To analyze the clinical distribution ,antimicbial resistance and Staphylococcal cassette chromosome mec (SCCmec) genotype characteristics of 346 methicillirrresistant Staphylococcus aureus (MRSA) clinical isolates in the hospital . Methods A total of 784 strains of Staphylococcus aureus isolated from January 2014 to January 2015 in the hospital ,MRSA identi-fication and the SCCmec genotype was conducted by PCR assay .Results 346 strains of MRSA (44 .13% ) were isolated from 784 strains of Staphylococcus aureus ,the detection rate of MRSA from sputum accounted for 43 .06% ,the secretion accounted for 48 .55% .MRSA was resistant to penicillin ,levofloxacin and erythromycin ,sensitive to vancomycin ,linezolid and teicoplanin .SCC-mec genotyping result showed that SCCmecⅡ was identified in 130 ,SCCmecⅢ in 196 ,SCCmecⅣ in 11 ,SCCmecⅤ in 9 .Conclusion SCCmecⅢ is the main genotypes of MRSA from our Hospital ,all of the MRSA strains are multi-resistant to tested antibiotics , but sensitive to vancomycin and teicoplanin .
5.Rapid detections of OprD2 gene in Pseudomoas aeruginosa using loop-mediated isothermal amplification
Huan WANG ; Qing HUANG ; Junfu HUANG ; Han XIA ; Zhao YANG ; Weiling FU
Chinese Journal of Laboratory Medicine 2013;(6):543-547
Objective To establish a rapid detection approach by visual interpretation directly for OprD2 resistance gene of Pseudomonas aeruginosa based on the Loop-mediated isothermal amplification (LAMP),and provide a quick and effective method for clinical monitoring of Pseudomonas aeruginosa strains.Methods Totally 47 strains of Pseudomonas aeruginosa collected from December 2011 to June 2012 in Southwest Hospital of microorganisms were prospectively studied.Four LAMP primers (two inner,two outer) were designed according to the six zones of the OprD2 gene of Pseudomonas aeruginosa.A positive reaction is indicated by the color change after adding an intercalating dye (hydroxy naphthol blue) to the reaction solution.This method was used to detect and analyze the distribution of OprD2 resistance gene in 47 strains of Pseudomonas aeruginosa and its coirelation with antibiotic resistance.Results The LAMP assays showed 100% specificity for the OprD2 gene,and the sensitivity (with the lowest detection limits of 17.414 μg/L) was 10-fold higher than that of conventional PCR assays.The OprD2 gene was negative in 23 strains by both conventional PCR and LAMP.In OprD2 negative strains,the resistance rate of cefotaxime,levofloxacin,aztreonam,piperacillin,imipenem and meropenem was 100% (23/23),57% (13/23),48% (11/23),48% (11/23),48% (11/23) and 43% (10/23).Compared with the OprD2 positive strains,statistical analysis showed that the resistance rate of imipenem,levofloxacin and meropenem in OprD2 negative strains increased significantly (chisquare value is 9.155,4.846,4.037,P value was 0.002,0.028,0.045,and so there was significant difference).Conclusions The established LAMP approach in this study enables rapid,sensitive and specific detection of OprD2 gene in Pseudomonas aeruginosa by visual interpretation.Deficiency of OprD2 gene confers Pseudomonas aeruginosa a basal level of resistance to carbapenems especially to imipenem.The identification of OprD2 gene distribution in Pseudomonas aeruginosa is helpful to the selection of antimicrobial agents in the infection treatment.
6.Genetic Mutations of HBV Core Region
Qing HUANG ; Guiyu WANG ; Junfu HUANG ; Hong PAN ; Jun LI ; Weiling FU
Chinese Journal of Nosocomiology 2009;0(14):-
OBJECTIVE To study the mutation profiles of hepatitis B virus(HBV) in the core regions.METHODS Based on the sequence alignment of all HBV genotypes,specific primers targeting all HBV genotypes were designed to amplify the core region of HBV followed by sequence analysis on the sequencing data available.RESULTS Among the 34 cases,23 cases showed mutations in the core region.According to the mutation profiles,the most common mutations were the A1762T(50.0%) and G1764A(52.9%) in the basic core promoter(BCP) regions,and it always showed as double mutations.The L60V in core gene regions was the secondary common mutations(17.6%).Among all patients,there were 18,6 and 10 cases showed mutations in BCP,pre-core,and core gene regions,respectively.The most common mutations in BCP,pre-core,and core gene regions were the double mutations at A1762T and G1764A(94.7%),G1896A(83.3%),and L60V(50.0%),respectively.CONCLUSIONS The most common mutations in the core region of HBV are the double mutations at A1762T and G1764A.Analysis on the mutation profiles of HBV core regions might be helpful for the prognosis and prediction of HBV infections.
7.Detecting Micro-luminescence of 330 Codon in emb gene of Mycobacterium tuberculosis by Molecular Beacon Hybridization
Qinghai CHEN ; Xing LIU ; Junfu HUANG ; Yang LUO ; Hong KUANG ; Weiling FU
Chinese Journal of Nosocomiology 2009;0(14):-
OBJECTIVE To design molecular beacon detecting embB330 codon of ethambutol-resistant Mycobacterium tuberculosis(MTB),meanwhile,and try to detect fluorescence of mutation site of embB330 codon in liquid by fluorescence microscope by compareing the mutation strains and standard strains.METHODS The software,Beacon designer,was used to design molecular beacon detecting embB330codon and detecting fluorescence signal from hybridization between the amplified product and probe by fluorescence microscope,and to confer to the sequencing results.RESULTS The difference between PCR products from standard strain and ethambutol-resistant one was obvious in detecting the fluorescent light by use of fluorescence microscope.We detected fluorescent light signal between the 33 ethambutol-resistant strains and 10 H37RV standard strains.The rate of ethambutol-resistant strains was about 3%,and the rate of sequencing was about 3%.CONCLUSIONS The technology of molecular beacon effectually can detect mutation single base site of embB330codon.Fluorescence microscope owns characteristics such as high sensitiveness to detect the fluorescent light.
8.Prevention of Nosocomial Infections in Laboratory Departments of Large Scale Hospitals:Current Situation and Measures
Xue ZHANG ; Yang LUO ; Bo ZHANG ; Junfu HUANG ; Weiling FU
Chinese Journal of Nosocomiology 2006;0(03):-
OBJECTIVE To analyze the reasons of nosocomial infection in laboratory departments, and then advance corresponding measures to overcome them. METHODS The current situations in laboratory department between domestic large scale hospitals and overseas hospitals were compared, especially paying attentions to those parts involving in management system and precautionary measures. RESULTS There were a lot of shortcomings existed in the supervision of nosocomial infections in laboratory departments; many measures should be taken to increase the management level. CONCLUSIONS To reform and improve the system of nosocomial infection control and prevention, and establish an effective and systematic alerting and prevention system will benefit all kinds of the hospitals.
9.DNA Staining Efficiencies of Different Fluorescent Dyes in Preparative Agarose Gel Electrophoresis:A Comparative Analysis
Qing HUANG ; Weiling FU ; Yuhui ZHAO ; Han XIA ; Junfu HUANG ; Bin CHEN
Chinese Journal of Nosocomiology 2005;0(11):-
OBJECTIVE To set-up safe alternatives to ethidium bromide(EB).METHODS Comparative analysis was performed on the DNA staining efficiencies of 4 fluorescent dyes including SYBR Gold,SYBR Green Ⅰ,(GoldView) and EB in preparative agarose gel electrophoresis.RESULTS Although both SYBR Gold and SYBR Green Ⅰ altered electrophoretic mobility and thus DNA size estimates,they were cost-effective alternatives to EB.SYBR Gold was more sensitive than SYBR Green Ⅰ at detecting short fragments,but 50 bp bands were clearly(visible) using either dye when visualized with a long integration time.CONCLUSIONS SYBR Gold or SYBR Green Ⅰ are sensitive and relatively safe alternatives to EB.
10.Detection of Pseudomonas aeruginosa with Piezoelectric Immunosensor Microarray:An Experimental Research
Qingmei WANG ; Weiling FU ; Xiaobing ZHANG ; Junfu HUANG
Chinese Journal of Nosocomiology 2005;0(11):-
OBJECTIVE To study the main bacteria and their drug-resistance of postoperative infections after liver transplantation.METHODS The distribution and drug-resistance profile of 156 strains of bacterial isolates from(various) specimens in 68 liver transplantation inpatients were retrospectively analyzed last year.RESULTS The(incidence) of infections after liver transplantation was 67.6 %.The major bacteria were Klebsilla pneumoniae((17.3%)),Staphylococcus aureus(14.1%),Candida albicans(11.0%),and Pseudomonas aeruginosa((11.0%)).The bacteria had the character of multidrug-resistance and high drug-resistance.The most effective(antibiotics) to Gram-negatives and Gram-positives were still the carbopenems and glycopeptide.CONCLUSIONS(Infection) is a major complication after liver transplantation.Prevention,early diagnosis and treatment of the(infection) are very important.

Result Analysis
Print
Save
E-mail