ABSTRACT
Objective To investigate the source of microbial contamination in the clean room of the workshop. Methods Microbiological sampling was carried out from the air, environment and personnel of the workshop. The samples were cultivated, the microorganisms were detected by MALDI-TOF-MS, and homology analysis was performed with the microbial identification system of the instrument. Results A total of 14 species and 41 strains of bacteria were detected. Nine strains of Staphylococcus epidermidis were selected for homology analysis, and the Staphylococcus epidermidis from personnel gloves and headgear had 94% homology. There was 83% homology among the staphylococcus epidermidis derived from the sedimentation bacteria, the ground environment and personnel, which was higher than the 71% of the standard strain. Conclusion The homology analysis demonstrates that the pollution in the clean room of the workshop mainly comes from personnel, and secondly comes from the environment outside the workshop. Enterprises need to strengthen management to prevent the occurrence of microbial contamination. MALDI-TOF-MS can be used for rapid detection of complex environmental bacteria and for homology analysis.
ABSTRACT
Objective@#To understand the epidemiologic features of the rabies in Xishuang banna prefecture of Yunnan province, China in 2008-2017 and the viral molecular-evolution characteristics.@*Methods@#The data of rabies case questionnaire were collected. The brain tissue samples from mad dogs, suspicious sick dogs and human brain tissue, saliva and cerebrospinal fluid samples from rabies patients were collected in Xishuangbanna. Coding region of nucleoprotein and glycoprotein genes were amplified by RT-PCR and sequenced. Homology and phylogenetic analysis were performed using the relevant bioinformatics software.@*Results@#A total of 62 cases of human rabies were occurred in 28 districts of the 3 counties, Xishuangbanna prefecture in 2008-2017. Of them, 37 cases in Jinghong county, 15 in Menghai county and 10 in Mengla county. In which 48 cases were bitten by domestic dogs (77.42%), 11 cases were bitten by wild dogs (17.74%). Rabies case was occurred every year in the past decade. The seasonal incidence was not obvious. The majority of patients were aged from 30 to 59 years-old, with the youngest 1 year-old and the eldest 91 year-old. The male to female ratio was 1.70∶1, most cases were farmers. The nucleotide sequences of nucleoprotein gene of 9 virus strains (7 from Jinghong, 1 from Menghai and 1 from Mengla) were obtained from the samples of dogs and patients. Homology and phylogenetic analyses indicated that the 5 strains belonged to clade China-Ⅰ, 3 clade China-Ⅱ and 1 clade China-Ⅵ. The nucleotide sequences of glycoprotein gene of 5 virus strains (3 from Jinghong, 1 from Menghai and 1 from Mengla) were obtained from these positive samples, and all were clade China-Ⅰ, it is same with nucleoprotein genes analysis result from these 5 virus strains. These China-Ⅰ and China-Ⅱ strains from Xishuangbanna have a closer genetic relationship with same clade strains isolated from Pu’er and other prefectures of Yunnan province as well as Sichuan, Guizhou and Guangxi. The China-Ⅵ strain from Xishuangbanna share high homology and genetic relationship with China-Ⅵ strains isolated from southwestern Yunnan and neighbouring countries such as Myanmar, Laos and Vietnam in recent years.@*Conclusions@#In Xishuangbanna, rabies mainly occurred in rural area and domestic dog was the main source of transmission. These RABV clades China-Ⅰ, China-Ⅱ and China-Ⅵ were found in this region and the China-Ⅰ was principal clade. The transmission source of China-Ⅰ and China-Ⅱ were from adjacent areas in the province and China-Ⅵ was from Myanmar and Laos.
ABSTRACT
OBJECTIVE: To analyze the microbial contamination and investigate the bacteriostatic efficacy of compound balloonflowers and ephedrine syrup(Ⅱ). METHODS: The compound balloonflowers and ephedrine syrup(Ⅱ) was analyzed for the bacteriostatic efficacy, content of bacteriostatic agent and C18 column was adopted with gradient elution. The mobile phase consisted of 0.02 mol•L-1 ammonium acetate solution and methanol. The detective wavelength was set at 255 nm. The contaminating bacteria detected in the samples were identified by VITEK2 Campact, MALDI-TOF-MS and 16S rRNA sequencing, and homology analysis was conducted for the contaminating bacteria in the samples from the same enterprise. RESULTS: The bacteriostatic efficacy of the products of one enterprise did not meet the requirements of Chinese Pharmacopoeia(2015 edition). There were excessive and uneven contamination of microorganisms in the samples. The dosages of bacteriostatic agents in some enterprises did not conform to the standard requirements. CONCLUSION: Production enterprises should strictly control the dosages of bacteriostatic agents and the stability of the production process, and strengthen the monitoring of the sterilization effect of the whole production process to improve product quality.
ABSTRACT
Objective To study the genotypes, epidemiological characteristics and homology of Noroviruses (NoV) circulating in Shenzhen in the winter of 2017. Methods RT-PCR was performed using Nov-specific primers after extracting viral genome from 313 fecal samples. Positive RT-PCR products were then sequenced. Phylogenetic trees were constructed based upon the gene sequences of isolated and reference NoV strains using Mega 4. 1 and Clustal W software. Results There were 26 NoV-positive samples and all belonged to G Ⅱ. 4 subtype. These strains shared high homologies with G Ⅱ. 4 ( KY407156), G Ⅱ. 4 (KY580757) and GⅡ. 4 (KX372682). Phylogenetic analysis also suggested that 88. 46％ of them had a lower homology with the NoV strains isolated in the same area in recent years and 46. 15％ were different from the epidemic strains in other provinces of China. Conclusion NoV GⅡ. 4 was the epidemic strain in Shenzhen during the winter of 2017. More attention should be paid to it from the local public health authori-ties considering its owned characteristics in epidemic and homology.
ABSTRACT
Objective T he drug resistance detection of carbapenem resistant Klebsiella pneumoniae (CRKP)isolated from 4 intensive care units(intensive care unit,emergency ward,neurology intensive care u-nit and cardiac intensive care unit)in the hospital was conducted,and the detection and homology analysis of resistance gene KPC was carried out.Methods 40 strains of non-repetitive CRKP were isolated from the in-tensive care units in the hospital from January to December 2015.Drug resistance detection was conducted by using minimal inhibitory concentration(MIC)method,The Hodge test was used for the phenotypic test of A type of carbapenems.Polymerase chain reaction(PCR)was used to amplify the KPC gene.The products were sequenced and analyzed.Homology analysis was performed on all strains using ERIC-Ⅱ as primers.Results 40 strains of CRKP showed high drug resistance rate;the positive rate of Hodge test was 100.0%,the resist-ance gene KPC were detected in 29 strains,the positive rate was 72.5%,and the sequencing results was type KPC-2;40 strains of CRKP can be divided into 7 types by homology analysis,including 28 strains of type A, accounting for 70.0%;2 strains of B type.Accounted for 5.0%;1 strains of C type,accounting for 2.5%;1 strains of D type,accounting for 2.5%;2 strains of E type,accounting for 5%;5 strains of F type,accounting for 12.5%;1 strains of G type,accounting for 2.5%.Conclusion The main drug-resistant genotype of CRKP isolated from all intensive care units in the hospital was KPC-2,including 7 types,among which is mainly A type,and there is a trend of epidemic transmission between ICU and emergency wards.
ABSTRACT
Objective To investigate drug resistance genes and epidemic characteristics of β-lactamase carried by carbapenem-resistant Acinetobacter baumannii (CRAB) in the respiratory intensive care unit(RICU) in a hospital.Methods Clinically isolated CRAB from RICU patients in October-December 2015 were collected.Five drug resistance genes (KPC-2,IMP,VIM,NDM-1,OXA-23) were specifically amplified by polymerase chain reaction (PCR),amplified products were performed agarose gel electrophoresis and sequencing analysis,the homology was analyzed with pulsed-field gel electrophoresis (PFGE).Results A total of 22 CRAB strains were isolated in October-December 2015,19 (86.36％) of which were isolated from sputum.The resistance rate of 22 CRAB strains to compound sulfamethoxazole was 59.09 ％,resistance rate to minocycline was 9.09 ％,all were sensitive to polymyxin B,resistance rates to other antimicrobial agents were more than 80％.Three kinds of resistance genes KPC-2,IMP and NDM-1 were not found by PCR amplification,positive rates of VIM and OXA-23 were both 100％.PFGE homology analysis revealed that 22 strains were divided into 13 different types,each type contained 1-5 strains,9 types(69.23％) contained only 1 strain respectively,the other 4 types (30.77％) contained 2-5 strains.A5,A7,and A8;A9,A11,A14,A19 and A22;A4,A10 and A12;A16 and A18 were of the same type respectively.Conclusion The main types of β-lactamase-resistant genes of CRAB in RICU are VIM and OXA-23.Homology analysis shows a small parts are of the same clone strains,which reveals epidemic of a small scale.
ABSTRACT
We investigated the molecular characteristics of the full-length genome of 5 dengue serotype 4 virus (DENV-4) strains isolated in Yunnan Province,China,2015 and their molecular epidemiological feature.Isolation of dengue virus was using C6/36 cell culture method.Viral RNA was extracted from virus isolates,then the full-length genome was amplified by RT-PCR.The homology and phylogenetic analysis was made on the nucleotide and deduced amino acid sequences by bioinfor matics softwares including ClastalX1.83 and MEGA6 etc.Results showed that five strains of DENV-4 isolated from dengue fe ver cases in Ruili City of Yunnan Province in 2015,of these,2 strains from indigenous cases,3 from imported cases from Lashio and Nam Can cities of Myanmar to Ruili of China.RT-PCR and sequencing indicated that the full-length genes (10 661 nt) of 5 DENV-4 strains were obtained,and their open reading frame (103-10 264) were coded 3 386 amino acid residues.Phylogenetic tree and homology analysis based on the comeplete genome or structural and non-structural protein genes showed that the 5 DENV 4 isolates were highly homologous and gathered in an evolution as well as they have a closer genetic relationship with the DENV-4 genotype Ⅰ (G-Ⅰ) strains isolated from Thailand.Results indicated that the Yunnan strains belonged to G-Ⅰ.Yunnan strains and Thailand strains compared with DENV 4 prototype strain (H241,Philippines 1956) and Guangzhou strain (B5,1990) of China and showed low homology and evolutionary relationship.When Yunnan strains compared with H241 strain,there were 21 and 45 different sites in amino acid of structural and non-structural proteins,respectively.This is the first time in Yunnan to obtain full-length genomes sequence of DENV-4 and they have closer evolutionary relationship with DENV 4G-Ⅰ strains from Southeast Asia region in recent years.The autochthonous DENV-4 epidemic in Yunnan was detected for the first time,and the virus transmission sources were from neighboring northern Myanmar.It is necessary to further study that change of the amino acid sites of Yunnan strains of DENV-4 is related to its antigenicity and virulence.
ABSTRACT
Objective To understand the homology of clinical isolates from patients with carbapenem-resistant Klebsiella pneumoniae(CRKP)infection and isolates from environment in a medical institution.Methods One CRKP strain isolated from a patient in this hospital and 4 strains of Klebsiella pneumoniae(K.pneumoniae)isolated from patient's surroundings were collected,susceptibility of 5 strains to commonly used antimicrobial agents was detected,production of carbapenems in 5 strains were detected by modified Hodge testing and carbapenem inactivation method(CIM),homology analysis was performed by pulsed-field gel electrophoresis(PFGE).Results Antimicrobial susceptibility testing results showed that 5 strains of K.pneumoniae(1 from patient,4 from the patient's ward surroundings,including hands of nursing aides,solution bottle opening,handle for lifting and dropping bed,and bedrail)were all resistant to other antimicrobial agents except to cephamycin and aminoglycosides.The modified Hodge testing and CIM confirmed that 5 strains all produced carbapenemases;PFGE results showed that electrophoretogram of CRKP isolated from solution bottle opening of ward,bedrail,and handle for lifting and dropping bed were the same as CRKP isolated from patient,while electrophoretogram of CRKP isolated from hands of nursing aides had 2 different bands,there was a close relationship between the strains.Conclusion The same type of CRKP were isolated from patient and his surroundings,it is necessary to implement healthcare-associated infection(HAI)control system,isolate infected patient,and strengthen environmental cleaning and disinfection,so as to avoid the outbreak of HAI.
ABSTRACT
Objective To study the homology relationship among clinically isolated imipenem-resistant klebsiella pneumoniae strains and possible transmission route of drug resistant strains to provide a basis for blocking the transmission of this kind of bacteria in clinc.Methods Clinical samples collection and bacterial culture were routinely conducted,meanwhile the hand surface of ICU medical staffs and the surfaces of patien's bedside objects were performed the sample collection for conducting the bacterial count and culture.The bacterial identification and drug susceptibility test were performed by the VITEK-2 COMPACT system.The bacterial homology detection adopted the ERIC-rep-PCR method.Results Totally 642 strains of imipenem-resistant Klebsiella pneumoniae were clinically isolated from January 2011 to December 2013.Among them,389 strains(60.59％) were derived from ICU.72 strains (11.21％) fsrom the respiratory department,53 strains (8.26％) from the neurology department,41 strains (6.39 ％) from the cardiovascular department,31 strains (4.83％) from the surgical department,11 strains (1.71％) from the gastroenterology department,5 strains (0.78 ％) from the renal department,17 strains (2.65 ％) from the emergency department and 23 strains(3.58％) from the other departments.One strain of imipenem-resistant Klebsiella pneumoniae was isolated from the IGU object surface.Among 642 clinical bacterial strains,there were 8 main clones,these 8 clone strains added up to 394 strains,which accounted for 61.37％ of whole bacterial strains,the other 248 strains were single clones.Conclusion The monoclonal prevalence of imipenem-resistant klebsiella pneumonia in this hospital actually exists.The contact transmission may be the possible transmission route of this kind of infection.
ABSTRACT
Objective To investigate the drug resistance rate and homology of Pseudomonas aeruginosa isolated from ICU in Mudanjiang Municipal First People′s Hospital from January to June 2015 to understand its prevalence situation in ICU and provide a basis for the rational prevention and control of nosocomial infection.Methods The Vitek-2 Compact fully automatic microbiologi-cal identification instrument was adopted to perform the drug resistance analysis on 126 strains of Pseudomonas aeruginosa from ICU detected by different pathways in the first half of 2015.The homology of bacterial strains was analyzed by pulse-field gel elec-trophoresis(PFGE).Results Two nosocomial infection monitorings were performed in ICU from January to June 2015.Four strains of Pseudomonas aeruginosa isolated from the nurse hand,medicative cart and doorknob of ICU ward all were sensitive strains;122 strains of Pseudomonas aeruginosa were detected in 110 ICU inpatients,in which 38 multi-drug resistant strains were detected from 18 ICU inpatients.The homology analysis was performed in 38 multi-drug resistant strains and 4 strains detected by nosocomial infection monitoring,these strains included 5 groups (A-E),which was dominated by the clone types of A,B and C, while the strains detected by nosocomial infection monitoring all were clone type B.Multiple subtype infection was detected in 4 pa-tients.Conclusion The infection situation of Pseudomonas aeruginosa is serious in ICU,no epidemic outbreak of strains detected by nosocomial infection monitoring exists.The cross prevalence of multiple clone strains exists in inpatients.
ABSTRACT
Objective To identify and analyze the homology of Ochrobactrum isolated from clinical blood samples of children.Methods The 26 strains of Ochrobactrum anthropi were identified by Vitek 2 Compact and test strips of API 20 NE bacterial identification system.The biochemical phenotypes were identified by manual tests.The 16S rRNA and recA gene were amplified by PCR and sequenced.The drug sensitivity tests of Ochrobactrum anthropi were performed by Vitek 2 Compact and matched GN13 card.The homology was analyzed by pulsed field gel electrophoresis.Results Based on the identification of the instruments and the manual tests for biochemical phenotype,all the 26 experimental strains were Ochrobactrum anthropi.The results of sequencing for 16S rRNA and recA gene amplification products showed 25 strains were Pseudochrobactrum saccharolyticum and the other 1 was O.grignonensein.Drug sensitivity analysis showed that the all the 26 strains were resistant to aztreonam,but the sensitive rates to quinolones,aminoglycosides,trimethoprim sulfamethoxazole,four generation of cephalosporins and the antibiotics compound of piperacillin/tazobactam were all more than 80％.Pulsed field gel electrophoresis analysis showed that the 25 strains were highly homologous with differences of only 1 to 3 bands in fingerprint profiles.Conclusion Based on the biochemical phenotype and the sequencing of 16S rRNA and recA gene,the Ochrobactrum-like bacteria could be identified to the level of species.The highly homologous strains of Pseudochrobactrum saccharolyticum may be sourced from a clustered infection.
ABSTRACT
Objective To investigate the antibiotic resistance pattern and molecular epidemiology of carbapenem-resistant Pseudomonas aeruginosa.Methods The antimicrobial susceptibility was measured by agar dilution method for the 104 strains of carbapenem-resistant P.aeruginosa (CRPA) collected from Huashan Hospital.The homology between these strains was evaluated by pulsed field gel electrophoresis (PFGE).Results Of thel04 CRPA strains,85.6％ were resistant to meropenem and 98.1％ to imipenem.These strains also showed various percentages of resistance to amikacin (18.3％),gentamicin (40.4％),ceftazidime (26.9％),cefepime (21.2％),ciprofloxacin (44.2％),levofloxacin (50.0％),piperacillin-tazobactam (19.2％),cefoperazone-sulbactam (26.9％),ticarcillin-clavulanic acid (52.9％),aztreonam (26.9％),and colistin (5.8％).PFGE analysis showed that these strains were divided into 48 types,belonging to 9 clones.Only 3 strains were non-typeable.Clone A was the primary epidemic strain (41.6％,42/101),which was mainly isolated from Neurosurgery,Geriatrics and General Ward.Clone B accounted for 5.9％ (6/101) of the strains.Conclusions Multiple clones of carbapenem resistant Pseudomonas aeruginosa were prevalent in Huashan hospital.Effective infection control approaches should be adopted to prevent the development and the further spreading of antimicrobial resistance.
ABSTRACT
We investigated the molecular characteristics of the full-length genome of 14 dengue serotype 1 virus (DENV-1)strains isolated in Sino-Myanmar border region in Yunnan Province,China during 2013-2015.Isolation of dengue virus was using C6/36 cell culture method.Viral RNA was extracted from virus isolates,and then the full-length genome was amplified by RT-PCR.The homology and phylogenetic analysis was made on the nucleotide and deduced amino acid sequences by bioinformatics software including ClastalX1.83 and MEGA6 etc.Results showed that fourteen strains of DENV-1 isolated from dengue fever cases,of these,9 strains from Ruili City of Dehong Prefecture,3 from Lincang Prefecture,2 from Kunming City.RT-PCR and sequencing indicated that the full-length genes (10 735 nt) of 14 DENV-1 strains were obtained,and their open reading frame (95-10 271) were coded 3 392 amino acid residues.The genotypes of DENV-1 were revealed by homology and phylogenetic analysis based on structural and non-structural proteins.Thirteen were genotype Ⅰ (G-Ⅰ) (7 from indigenous cases in Ruili and Lincang and 6 from imported case from Myanmar to Ruili,Lincang and Kunming),and 1 G-Ⅲ from imported case from India to Kunming.The phylogenic analysis indicated that the 13 isolates from Yunnan divided into 2 phylogenic subgroups,and they had a closer genetic relationship with the strains isolated from Southeast Asia.The gene sequences of the 13 G-Ⅰ strains have been acquired,the rate of their nucleotide homology and amino acid homology were 97.02 ％-100 ％ and 98.78 ％100 ％ respectively.Compared with 6 strains from Southeast Asia,nucleotide homology and amino acid homology were 96.53％-99.53％ and 97.33％-100％ respectively.Compared with prototype strain (US_Hawaii) of DENV-1,nucleotide homology and amino acid homology were 93.76％-94.45 ％ and 95.86 ％-96.91％ respectively.Compared with US_Hawaii strain,there were 44 and 150 different sites in amino acid of structural and non-structural proteins,respectively.The G-1 of DENV-1 have been popular in Sino-Myanmar border region in Yunnan,2013-2015.They have genetic diversity but multiple transmission sources were from Myanmar,and should strengthen control cross-border spread of dengue fever in this region.It is necessary to further study that change of the amino acid sites of Yunnan strains of DENV-1 is related to its antigenicity and pathogenicity.
ABSTRACT
Objective To understand the homology of sequence type 562 (ST562) strains of Burkholderia pseudomallei which circulated in two separate continents (Asia and Australia) at different times.Methods Spe Ⅰ restriction fragments and 4-locus multiple locus variable number tandem repeat analysis (MLVA-4) profiles were extracted from MSHR5858 (ST562 Australia strain) and 350105 (ST562 historical strain of Hainan) genomes respectively by in silico analysis and then compared with the PFGE and MLVA-4 results of five ST562 clinical isolates from Hainan to test their homology.Synteny and homology between MSHR5858 and 350105 genomes were evaluated with bioinformatics methods.Results Five ST562 clinical strains from Hainan shared same PFGE pattern (similarity ＞97％) and this pattern coincided to the map of Spe Ⅰ restriction fragments of Australian strain MSHR5858.The amounts of genomic restriction fragments (Spe Ⅰ) for MSHR5858 and 350105 were 31 and 34 respectively,with 31 of them matched by each other.Five ST562 clinical strains of Hainan were distinct by MLVA-4 profiles,among which HPPH43 (MLVA-4 profile:10,8,10,8) was close to Australia strain MSHR5858 (10,8,8,6),containing identical repeat numbers at VNTR loci 2341k and 1788k;while HK003 (11,8,15,7) and HK061 (11,8,17,7) similar to Hainan historical strain 350105 (11,8,11,8),with same repeat numbers at loci 2341k and 1788k also.High-degree synteny and consistency on genomic contents were observed between 350105 and MSHR5858,indicating a similar origin for the 2 strains.Conclusion All inter-continental and historical ST562 strains ofB.pseudomallei had similar genomic characteristics,supporting the assumption that they had a common origin.Also,it is possible that Hainan historical strain 350105 is the ancestor of all circulating ST562 strains.
ABSTRACT
Objective To understand the homology of sequence type 562 (ST562) strains of Burkholderia pseudomallei which circulated in two separate continents (Asia and Australia) at different times.Methods Spe Ⅰ restriction fragments and 4-locus multiple locus variable number tandem repeat analysis (MLVA-4) profiles were extracted from MSHR5858 (ST562 Australia strain) and 350105 (ST562 historical strain of Hainan) genomes respectively by in silico analysis and then compared with the PFGE and MLVA-4 results of five ST562 clinical isolates from Hainan to test their homology.Synteny and homology between MSHR5858 and 350105 genomes were evaluated with bioinformatics methods.Results Five ST562 clinical strains from Hainan shared same PFGE pattern (similarity ＞97％) and this pattern coincided to the map of Spe Ⅰ restriction fragments of Australian strain MSHR5858.The amounts of genomic restriction fragments (Spe Ⅰ) for MSHR5858 and 350105 were 31 and 34 respectively,with 31 of them matched by each other.Five ST562 clinical strains of Hainan were distinct by MLVA-4 profiles,among which HPPH43 (MLVA-4 profile:10,8,10,8) was close to Australia strain MSHR5858 (10,8,8,6),containing identical repeat numbers at VNTR loci 2341k and 1788k;while HK003 (11,8,15,7) and HK061 (11,8,17,7) similar to Hainan historical strain 350105 (11,8,11,8),with same repeat numbers at loci 2341k and 1788k also.High-degree synteny and consistency on genomic contents were observed between 350105 and MSHR5858,indicating a similar origin for the 2 strains.Conclusion All inter-continental and historical ST562 strains ofB.pseudomallei had similar genomic characteristics,supporting the assumption that they had a common origin.Also,it is possible that Hainan historical strain 350105 is the ancestor of all circulating ST562 strains.
ABSTRACT
Objective To analyze the drug resistance and homology of Acinetobacter baumannii (Ab) isolated from patients with explosive injury ,so as to explore the characteristics of drug resistance and prevalence of infection .Methods A total of 61 strains of AB isolated from clinical specimens of patients with explosive injury were collected .The antimicrobial susceptibility of these iso‐lates was detected by using K‐B test .All the strains were gene typed by using the pulsed field gel electrophoresis .Results The re‐sults of antimicrobial susceptibility test shown that the 61 isolates of Ab had high resistance rate ,and were multi‐drug resistant to common antibacterial agents ,except for tigecycline (the resistante rate was 11 .5% ) and minocycline (the resistante rate was 48 .0% ) .The 61 isolates of Ab were divided into 8 kinds of genotypes ,among which type A was the most prevalent one (25 strains) .Other genotypes were type B(10 strains) ,type C(6 strains) ,type D(4 strains) ,type E(8 strains) ,type F(3 strains) ,type G(4 strains) and type H(1 strain) .The isolates of Ab were with high homology .Conclusion Multi‐drug resistance is observed in strains of Ab isolates from patients with explosive injury .Clonal strains of AB may be disseminates among regions ,which indicates that high attention should be paid to these strains .
ABSTRACT
Objective Pathogens from the nosocomial infection have been analyzed by MALDI‐TOF microbial identification system ,to evaluate mass spectrometry analysis advantage and explore the mass spectrometry method .Methods The pathogens have been analyzed by MALDI‐TOF microbial identification system ,by compared with the VITEK‐2 compact detection in the tes‐ting time ,detection rate and the amounts of identified strains .The homology differences have been analyzed by comparison calcula‐tion of common peaks from the fingerprint spectrums .Results Thirty‐one Escherichia coli strains ,28 Klebsiella pneumonia strains and 9 unusual pathogen strains have been identified by MALDI‐TOF MS for only 1 hours .It has more advantages than VITEK‐2 in the testing time and other aspects .Conclusion Nosocomial infection of pathogen shows a point source propagation mode centering on the department .MALDI‐TOF mass spectrometry is able to rapidly and correctly identify the pathogen .MALDI‐TOF microbial i‐dentification system is expected to be the major detecting technique in the field of the pathogen monitor and resistance monitoring a ‐nalysis .
ABSTRACT
ObjectiveTo establish the rapid molecular diagnosis of 16 common coagulase negative Staphylococcus(CNS).MethodsDNA sequencing of 16 CNS would be obtained with gap gene.After the alignment gap gene sequences which were available in the GenBank,the bacteria were identified with homological alignment and phylogenetic tree,and compared with the 16S rRNA gene.ResultsThe sequence similarity of the gap sequences ranged from 39% to 98% in 16 CNS.There were the highest similarity (98%) between S.hominis and S.hominis subsp,and the lowest(39% ) between S.saprophyticus and S.xylosus.The sequence similarity of the 16S rRNA sequences ranged from 96 to 98%,at least two species of bacteria similar rate of 99% and the most four species similar rate of 99%.Phylogenetic homology analysis showed that it was a high confidence(99% ) in the detection ofS.xylosus and S.lentus,S.chromogenes and S.intermedius,S.hominis and S.hominis subsp,but for 10 other species of bacteria,gap homology analysis has less unreliable confidence(49%,56% ) and 16S rRNA has more unreliable confidence(43%,43%,50%,56%,63%,65%,76% ).ConclusionAnalysis of gap sequence could identify 16 CNS timely and accurately,with higher confidence than 16S rRNA.
ABSTRACT
Objective To understand the genetic characteristics of Enterovirus 71 ( EVT1 ) circu-lating strains of Guangdong province in 2008. Methods We isolated an EV71 strain from the fatal case of the hand, foot and mouth disease during an epidemic of Guangdong in 2008. Its complete genome was se-quenced and analyzed comparatively. Results The results showed that the full length of EV71 GDFS-3 ge-nome( not including poly A tail ) is 7405 bp. No insertion or deletion is detected in the coding region. There are several insertions and deletions in 5'and 3'UTR. Phylogenetic analysis of GDFS-3 and reference strains showed GDFS-3 strain shares the highest nueleotide homology with TW984 strain(96.0% ) but low homology with SIN5865, MS and BrCr( about 81.0% ). GDFS-3 strain also shares the highest amino acid homology with TW984 strain(99.0% ). It clustered with reference strains of CA subgenotype in the phylogenetie tree. The nucleotide identity with CA reference strains is 91.0% -95.0%. Conclusion The phylogenetic analysis based on the entire genome demonstrates that GDFS-3 strain has the nearest genetic relationship with TW984 strains ( isolated in 2004). GDFS-3 may belong to the same subgenogroup ( CA ) with Taiwan predominant strains. Otherwise,Some mutations in 5'UTR of EV71 may play the very important role in heightened viru-lence.
ABSTRACT
To gain a better understanding of the genetic diversity and evolution of PRRSV in the Ningxia Hui Nationality Autonomous Region (Ningxia) of China, the nsp2 genes from a series of PRRSV strains collected from the region in 2007 were partially sequenced. These sequences were then analyzed along with the classical strain (ch-la) and two other epidemic strains SD (3) and SD2006. Comparison of the nucleotide sequence with ch-la indicated that nsp2 genes of seventeen Ningxia isolates (NX strain) have deletions of 87 nucleotides. Sequence analysis indicated that homology between the Ningxia strain and ch-la was 60.3%-79.9% in the nucleotide sequence, and homology between the NX strains and SD strains was 80.3%-98.8% in the nucleotide sequence. The nsp2 genes of the seventeen isolates had 74.9%-100% nucleotide sequence identities with each other. This study was undertaken to assess the regional variation of prevalent PRRSV and to establish a sequence database for PRRSV molecular epidemiological studies.