1.Determination of MDPV in human urine by liquid-phase small-extraction-GC/MS
Renxin YAN ; Guoyu ZHU ; Jianzhong SHI ; Weibing WU
Chinese Journal of Forensic Medicine 2017;32(6):639-641
Objective The method for the analysis of Methylenedioxypyrovalerone (MDPV) in urine by liquid-phase small-extraction- GC/MS have been developed and studied . Methods A 1-mL of urine sample was adjusted to pH9 with sodium bicarbonate, and was extracted with 50μL dichloromethane. The mixture centrifuged at 14000g for 2 min . A 1-μL organic phase was injected into the GC/MS system. Results The calibration curves showed good linearity in range of 0.05μg/mL~0.20μg/mL , and the limit of detection was 0.02μg/mL, and the RSD was 3.86~5.69%, and the recovery rate was 86.5~92.8 %. Conclusion The method is sensitive, accurate and was easy to operate for fast detection of MDPV in human urine.
2.Phylogeny and virulence gene profile of Francisella salimarina
Xiaowei CHEN ; Qiwei LI ; Yan CHEN ; Shunguang LI ; Jiafan CHEN ; Chao YANG ; Cha CHEN ; Pinghua QU ; Renxin CAI
Chinese Journal of Microbiology and Immunology 2023;43(8):612-618
Objective:To study the molecular phylogeny and virulence gene profile of Francisella salimarina. Methods:Phylogenetic analysis of Francisella salimarina was performed based on the global genome data of related Francisella species on GenBank database. The consistency in phylogenetic analysis based on single marker genes (such as 16S rRNA gene, rpoB gene and mdh gene) and the core genome as compared. Virulence genes and antibiotic resistance genes were annotated using the virulence factor database (VFDB) and the Comprehensive Antibiotic Resistance Database (CARD), respectively. The virulence of Francisella salimarina was analyzed with a Galleria mellonella (greater wax moth) infection model using Francisella philomiragia ATCC 25015 T as reference strain. Results:The phylogenetic analysis revealed that Francisella salimarina was closely related to Francisella philomiragia. The phylogenetic tree based on mdh gene was highly similar to that based on the core genome. Francisella salimarina could be differentiated from other related species by 16S rRNA gene or mdh gene, with the latter being more accurate. Eight Francisella salimarina strains carried multiple virulence genes, mainly involved in secretion, adhesion, immune regulation, motility and stress survival. Moreover, beta-lactam resistance gene blaFPH was identified in all eight strains. Francisella salimarina showed high lethality in the Galleria mellonella infection model, which was similar to Francisella philomiragia ATCC 25015 T. Conclusions:Francisella salimarina was a rare pathogen with similar pathogenicity to Francisella philomiragia. The mdh gene could be used as a molecular target for rapid identification of Francisella salimarina.
3.Effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source in Sichuan Province from 2010 to 2022
Wei HE ; Wenjie YU ; Yan HUANG ; Sha LIAO ; Guangjia ZHANG ; Qi WANG ; Ruirui LI ; Liu YANG ; Renxin YAO ; Zhongshuang ZHANG ; Bo ZHONG ; Yang LIU ; Qian WANG
Chinese Journal of Schistosomiasis Control 2023;35(6):614-620
Objective To evaluate the effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source in Sichuan Province from 2010 to 2022, so as to provide insights into formulation of future control interventions. Methods Data pertaining to comprehensive echinococcosis control measures with emphasis on management of infectious source and echinococcosis surveillance in Sichuan Province from 2010 to 2022 were collected. The effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source was evaluated with prevalence of human echinococcosis, detection of newly diagnosed echinococcosis patients, prevalence of Echinococcus infection in domestic dogs, prevalence of cystic echinococcosis in livestock, prevalence of alveolar echinococcosis in small mammals and awareness of echinococcosis control knowledge, and Spearman’s rank correlation analysis. Results The prevalence of human echinococcosis reduced from 1.08% in 2010 to 0.40% in 2022 in Sichuan Province (χ2 = 1 482.97, P < 0.05), with a reduction from 0.30% to 0.02% in the detection of newly diagnosed echinococcosis cases (χ2 = 2 776.41, P < 0.05), a reduction from 15.87% to 0.46% in the prevalence of Echinococcus infection in domestic dogs (χ2 = 20 823.96, P < 0.05), a reduction from 8.05% to 1.07% in the prevalence of cystic echinococcosis in livestock (χ2 = 1 296.02, P < 0.05), and the awareness of echinococcosis control knowledge increased from 50.65% to 95.24% (χ2 = 34 938.63, P < 0.05); in addition, there was a year-specific prevalence rate of alveolar echinococcosis in small mammals (χ2 = 164.07, P < 0.05). Spearman’s rank correlation analysis revealed that the detection of newly diagnosed echinococcosis cases correlated positively with the prevalence of Echinococcus infections in domestic dogs (rs = 0.823, P < 0.05) and the prevalence of cystic echinococcosis in livestock (rs = 0.795, P < 0.05), and correlated negatively with the awareness of echinococcosis control knowledge (rs = − 0.918, P < 0.05), and the prevalence of Echinococcus infection in domestic dogs correlated positively with the prevalence of cystic echinococcosis in livestock (rs = 0.753, P < 0.05) and negatively with the awareness of echinococcosis control knowledge (rs = −0.747, P < 0.05); however, there was no correlation between the prevalence of Echinococcus infections in domestic dogs and the prevalence of alveolar echinococcosis in small mammals (rs = −0.750, P > 0.05). Conclusions The comprehensive echinococcosis control measures with emphasis on management of infectious source had achieved remarkable effectiveness in Sichuan Province; however, the transmission chain of echinococcosis has not been interrupted. Reinforced comprehensive echinococcosis control measures with emphasis on management of infectious source and sustained tracking evaluation of the effectiveness are recommended in Sichuan Province.