Changes and clinical significance of antimicrobial peptide LL-37 and CRP in patients with Pseudomonas aeruginosa positive sputum culture / 国际检验医学杂志

Objective To investigate the changes of antimicrobial peptide LL-37 and C-reactive protein (CRP ) in the patients with Pseudomonas aeruginosa positive sputum culture and their mutual relation . Methods Fifty cases of Pseudomonas aeruginosa positive sputum culture and 27 cases undergoing physical ex-amination in the Guangdong Provincial Hospital of Chinese Medicine from September 2016 to May 2017 were selected as the research subjects .The level of antimicrobial peptide LL-37 was detected by double antibody sandwich ELISA and the CRP level was detected by immunoturbidimetry .Results The levels of antimicrobial peptide LL-37 and CRP in the Pseudomonas aeruginosa positive sputum culture group were significantly high-er than those in the healthy control group ,the difference was statistically significant (P< 0 .05) ,and they showed the positive correlation (r=0 .411 ,P<0 .05) .Conclusion In positive sputum culture of Pseudomonas aeruginosa ,antimicrobial peptide LL-37 and CRP levels are increased ,which has a certain clinical application value for the early diagnosis of infection .

Identification and classification of non-tuberculosis Mycobacterium by matrix-assisted laser desorption ionization-time of flight mass spectrometry / 中华检验医学杂志

Objective Reference standard of the RPOB(rifampin resistance)gene recommended by CLSI-MM18A(Interpretive Criteria for Identification of Bacteria and Fungi by DNA Target Sequencing) was used to evaluate the ability of MALDI-TOFMS techniques for the identification and classification of non-tuberculous Mycobacterium.Methods Fifty five clinicalstrains were collected from 2012 to 2016 with different sources.The RPOB gene was sequenced, and results were applied to phylogenetics analysis. MALDI-TOF MS technology was implemented to identify the strains, and cluster analysis was conducted based on protein fingerprint.The consistency of two methods for NTM identification and typing was evaluated.Results The RPOB gene method showed a good ability of identification(similarity>99.0%) and subtyping(to subspeciesof the complex level).The French BioMérieux MALDI-TOF MS identified 89.1% of 55 strains to genus level and 78.2% to species level.The phylogeneticsanalysis of protein fingerprint by SARAMS Premium software also showed good typing ability.Conclusions MALDI-TOF MS technology can identify and classify non-tuberculous Mycobacterium effectively,which is rapid and easy.It is complementary to RPOB gene method in laboratory application.

Identification of Streptobacillus moniliformis isolated from the knee joint pus by 16S rRNA gene sequencing and biochemical reactions / 实用医学杂志

Objective To indentify Streptobacillus moniliformis isolated from the knee joint pus by 16S rRNA gene sequencing and biochemical reactions and explore the clinical value of the method. Methods The bacterial 16S rRNA gene sequence-based identification, bacterial morphology, VITEK 2 automate systems, API 20NE strips, API 20E strips and API 50CH were performed to identify the rare bacteria. Results The bacteria grew slow on blood agar and chocolate agar and were inhibited on Maconkey agar. The bacterial colony on blood agar tookes the form of 1~2 mmomelette, which was translucent and moist with circular protrusion and smooth edges. They were Gram-staining negative and in catenation, its thalli 1~3μm, round, oval or fusiform. Vitek 2 GN-13, API 20NE and API 20E were unable to reach the identification of the bacteria. 16S rRNA gene sequencing showed the bacteria were similar to streptobacillus moniliformis by 100%. Conclusion The rare bacteria isolated from left knee joint are streptobacillus moniliformis. 16S rRNA gene sequences combined with the biochemical reactions is accurate in the identification of these bacteria.

Use ITS gene sequence analysis to identify dematiaceous fungi / 实用医学杂志

Objectives Use ITS gene sequence analysis to identify 15 strains of dematiaceous fungi , to learn the types of pathogenic strains and clinical treatment. Methods By observing the colony morphology and microscope morphological of the dematiaceous fungi isolated from superficial mycoses , and identified by ITS gene sequence analysis. Results 15 strains were identified by morphological observation as dematiaceous fungi.The amplified bands were identified by Tanon-3500 gel imaging system between 500 ~ 700 bp. Blast sequencing results show that 2 strains Alternaria alternate , 2 strains Cladosporium sphaerospermum. 2 strains Exophiala dermatitis, 1 strains Cladosporium cladosporioides, Curvularia lunata, Talaromyces rugulosus, Phaeobotryon cupressi, Cladosporium tenuissimum, Fonseceea pedrosoi, Exophiala werneckii, Exophiala oligosperma and Fonsecaea monophora. Conclusion ITS gene sequence analysis can identify dematiaceous fungi effectively , avoided undetected and misdiagnose cause by the lack of clinical experience.

Identification of the strain 1012 isolated from the sample of EQA of the Chinese National Center of Clinical Laboratory, and phylogenetic analysis of Actinomyces turicensisand related bacteria in the family Actinomycetaceae / 中华检验医学杂志

ObjectivesTo identified the strain 1012 from the National Center of Clinical Laboratory of China for microbe inter-laboratory quality assessment in 2010, and study the taxonomic status of strain 1012 and related species in the genus Actinomyces. Methods The bacterial traditional morphological characteristics, commercial API systems, and 16S rRNA gene sequence analysis were applied to identify the problematic culture of strain 1012. The phylogenetic tree based on the remote information of the prokaryotes systems was constructed to study the taxonomic status and evolutionary relationship of the genus Actinomyces and related species in the family Actinomycetaceae. Results Strain 1012 was determined as a kind of facuhative anaerobic,non-spot-forming,Gram-positive coryneformbacteria,which was identifiedto Actinomyces turicensis for the phenotypic biochemical characteristics of more than 60 items, The comparative study of 16S rRNA gene showed the strain 1012 with 99. 8％ similarities to Actinomyces turicensis, but only 90. 6％ to the type species of Actinomyces bovis in the genus Actinomyces. However, the comparative study of 16S rRNA gene showed the strain 1012 with only 90. 6％ homology to the type species of Actinomyces bovis in the genus Actinomyces. Further phylogenetic analysis showed that nine independent clusters were grouped in the family Actinomycetaceae, of which four clusters were separately represented the genera Varibaculum,Mobiluncus, Actinobaculum and Arcanobacterium, while other five clusters all were designated to the genus Actinomyces. The study showed strain 1012 was located in genus Ⅲ of Actinomyces, yet with a relatively long genetic distance to Actinomyces bovis. ConclusionThe genus Actinomyces may be reclassified as one genus Actinomyces sensu stricto and several new genera for the genotypic characteristics.