Objective:To investigate the drug resistance gene characteristics, plasmid characteristics and genome tracing of Shigella sonnei causing a bacillary dysentery outbreak in Shandong Province. Methods:Sixty-five Shigella sonnei strains isolated from a 2021 outbreak in a county of Shandong Province were analyzed using antimicrobial susceptibility testing, whole genome sequencing (WGS), characterization of resistance and virulence genes, plasmid profiling, core genome multilocus sequence typing (cgMLST), and single nucleotide polymorphism (SNP) analysis. Results:All isolates had the same resistance phenotype and genotypes and were multidrug-resistant ESBL-producing Shigella sonnei, carrying important virulence genes. Plasmid analysis revealed a conserved genetic arrangement, pil( M/ N/ O2/ P)-tra( F/ H/ J/ K/ N/ O/ P/ Q)-IS Ecp1- blaCTX-M-14-Tn 903- yub( J/ I/ F/ G/ E/ D), and shared across strains from diverse regions and bacterial species. The cgMLST and SNP analyses demonstrated concordant clustering, with all 65 outbreak-related strains forming a single cluster alongside human-derived strains from Guangxi. Conclusion:The ESBL-producing Shigella sonnei responsible for the outbreak shares a homologous relationship with Guangxi human-derived strains, and the detected resistance plasmids and virulence genes underscore the need to strengthen drug resistance surveillance and genome tracing.

Objective:To investigate the drug resistance gene characteristics, plasmid characteristics and genome tracing of Shigella sonnei causing a bacillary dysentery outbreak in Shandong Province. Methods:Sixty-five Shigella sonnei strains isolated from a 2021 outbreak in a county of Shandong Province were analyzed using antimicrobial susceptibility testing, whole genome sequencing (WGS), characterization of resistance and virulence genes, plasmid profiling, core genome multilocus sequence typing (cgMLST), and single nucleotide polymorphism (SNP) analysis. Results:All isolates had the same resistance phenotype and genotypes and were multidrug-resistant ESBL-producing Shigella sonnei, carrying important virulence genes. Plasmid analysis revealed a conserved genetic arrangement, pil( M/ N/ O2/ P)-tra( F/ H/ J/ K/ N/ O/ P/ Q)-IS Ecp1- blaCTX-M-14-Tn 903- yub( J/ I/ F/ G/ E/ D), and shared across strains from diverse regions and bacterial species. The cgMLST and SNP analyses demonstrated concordant clustering, with all 65 outbreak-related strains forming a single cluster alongside human-derived strains from Guangxi. Conclusion:The ESBL-producing Shigella sonnei responsible for the outbreak shares a homologous relationship with Guangxi human-derived strains, and the detected resistance plasmids and virulence genes underscore the need to strengthen drug resistance surveillance and genome tracing.

Objective:To explore the diagnostic value of thromboelastography (TEG) combined with conventional coagulation test (CCT) for trauma-induced coagulopathy (TIC) in patients with electric burns in the early stage.Methods:This study was a retrospective case series research. From February 2018 to February 2024, the clinical data of 128 electric burn patients and 118 thermal burn patients who met the inclusion criteria and admitted to the Department of Burn Surgery of the Third Affiliated Hospital of Inner Mongolia Medical University were collected, including 224 males and 22 females, aged (38±14) years. The patients were divided into electric burn group (128 cases) and thermal burn group (118 cases) according to their injuries. The incidence of TIC, the indicators of CCT, including prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen level, D-dimer level, platelet count, and the detection indicators of TEG, including coagulation reaction time, K value, coagulation angle, maximum thrombus amplitude, comprehensive coagulation index, and lysis rate at 30 minutes after maximum amplitude within 8 hours of admission were compared between the two groups of patients. The Kappa test was used to analyze the consistency between CCT and TEG in diagnosing TIC in patients with electric burns in the early stage after burns. The receiver operating characteristic curves of CCT, TEG, and TEG combined with CCT in diagnosing TIC in 128 patients with electric burns were drawn, and the area under the curve (AUC), the maximum Jordan index, and sensitivity and specificity at this time were calculated.Results:The proportion of patients diagnosed with TIC in electric burn group was 19.5% (25/128) within 8 hours of admission, which was significantly higher than 10.2% (12/118) in thermal burn group ( χ2=4.21, P<0.05). Compared with those in thermal burn group, prothrombin time was significantly shortened ( t=-2.32, P<0.05), D-dimer level, fibrinogen level, and platelet count were significantly increased (with Z values of -2.11 and -4.16, respectively, t=4.69, P<0.05), the coagulation reaction time was significantly shortened ( t=-2.51, P<0.05), and the maximum thrombus amplitude and lysis rate at 30 minutes after the maximum amplitude were significantly increased (with t values of 2.50 and 2.10, respectively, P<0.05) in patients in electric burn group within 8 hours of admission. There were no statistically significant differences in the other CCT indicators and TEG detection indicators between the two groups of patients ( P>0.05). The CCT and TEG showed high consistency in the diagnosis of TIC in patients with electric burns in the early stage after burns (Kappa=0.63, P<0.05). The AUCs of TEG combined with CCT, TEG, and CCT in diagnosis of TIC in 128 patients with electric burns were 0.92, 0.84, and 0.77 (with 95% confidence intervals of 0.86-0.97, 0.71-0.97, and 0.71-0.97, respectively), with the maximum Jordan indexes of 0.86, 0.57, and 0.65. At this time, the specificity was 93.7%, 83.2%, and 88.2%, respectively, and the sensitivity was 92.3%, 87.5%, and 76.5%, respectively. Conclusions:Patients with electric burns are in a state of hypercoagulability of coagulation system and hyperfunction of fibrinolysis system in the early stage after burns, and TEG combined with CCT can increase the diagnostic rate of TIC in patients with electric burns.

OBJECTIVE To explore the role of Yes-associated protein(YAP)in epidermal stem cell(EPSC)differentiation after ionizing radiation(IR).METHODS ① A punch was used to induce skin injuries on the back of mice.The IR group received localized irradiation with 60 Co γ-rays,while the normal control group did not.Samples were collected at 0,1,3,6,9,and 12 d for RNA and protein extraction.Western blotting was used to detect changes in YAP protein expressions during wound healing.Real-time quantitative polymerase chain reaction(RT-qPCR)was performed to assess the mRNA levels of Yap and its downstream target genes,connective tissue growth factor(Ctgf),and cysteine-rich protein 61(Cyr61).② EPSCs were exposed to 60 Co γ at a dose of 4 or 8 Gy,while the control group was not irradiated.Cells were collected to detect the levels of YAP protein via Western blotting.Cells were collected at 4,12,24,and 36 h post-IR to assess the levels of YAP mRNA by RT-qPCR.③ Short hairpin RNA(shRNA)was used to establish stable YAP knockdown cell lines,and the knockdown efficiency of sh YAP was verified by Western blotting.RT-qPCR was then performed to detect the impact of YAP knockdown on mRNA levels of K1 and K10 after IR.RESULTS① Compared with the control group,the YAP protein level in the IR group during wound healing was significantly reduced(P<0.05,P<0.01),so were the mRNA levels of Yap and its downstream target genes Ctgf and Cyr61(P<0.05,P<0.01).② Compared to the cell control group,the mRNA and protein levels of YAP in the IR group cells were significantly reduced(P<0.01).③ In the sh YAP cells,the YAP protein level was significantly reduced(P<0.01).Furthermore,the mRNA levels of K1 and K10 were significantly decreased after IR in sh YAP cells(P<0.01).CONCLUSION YAP can regulate EPSC differentiation in wound healing after IR.

Objective:To analyze the cause and epidemiological characteristics of an outbreak of cutaneous anthrax in Caoxian County, Heze City, Shandong Province, and to provide scientific basis for anthrax prevention and control.Methods:Using on-site epidemiological investigation methods and the "Anthrax Epidemiological Case Investigation Form", case investigations were conducted based on the epidemiological contact history and close contacts of suspected anthrax cases reported by the national health care system ( n = 83). Scorched skin smears, diseased cattle tissues, soil samples from the slaughter site and smears from slaughter utensils were collected from cases for Real-time PCR testing and pathogenic bacteria isolation and culture, respectively. Anthrax determination criteria were carried out with reference to "Anthrax Diagnosis" (WS 283-2020). Results:A total of 13 cases of cutaneous anthrax were found in this outbreak, including 12 clinically diagnosed cases and one confirmed case (positive Real-time PCR test and isolation of a strain of Bacillus anthracis). The epidemiological investigation determined that the source of infection in this outbreak was diseased cattle, the transmission route was through slaughter of diseased cattle, contact with contaminated utensils and related cattle products, and the patients were mainly engaged in occupations related to cattle slaughter or cattle product collection and sale. A total of 84 samples were collected, including 13 skin scabs, 64 environmental samples and 7 beef samples. Thirty-six positive PCR tests were performed, with a positive rate of 42.86% (36/84). Among them, 100.00% (13/13) were positive for skin scab smear specimens, 29.69% (19/64) for environmental samples and 4/7 for beef samples. A total of 8 strains of Bacillus anthracis were isolated, including 6 environmental specimens, 1 suspected case and 1 beef strain, with an overall detection rate of 9.52% (8/84). Eighty-three close contacts were investigated. Thirteen households involved in the epidemic were disinfected by spraying (200 ml/m 2) with chlorine-containing disinfectant (5 000 mg/L), and a total of 40 households involved in the epidemic were disinfected, covering an area of about 10 765 m 2. Forty-five pieces of suspected contaminated clothing were burned and disposed of, and 152 pieces of kitchenware were soaked. Conclusions:Slaughter of infected cattle, contact with contaminated utensils and related cattle products are the main causes of this skin anthrax outbreak. Strengthening market supervision, deepening inter-animal epidemic prevention, carrying out publicity and education on anthrax prevention and control, and enhancing practitioners' awareness of disease prevention is the key to prevent anthrax from occurring.

Objective:To learn about the epidemiological and spatial clustering characteristics of brucellosis in Shandong Province, and to provide a reference for scientific prevention and control of brucellosis.Methods:The epidemic data of human brucellosis in Shandong Province from January 2015 to December 2020 were collected from the Infectious Disease Reporting Information Management System of China Disease Control and Prevention Information System, and the data were analyzed by descriptive epidemiology and spatial clustering analysis.Results:A total of 18 811 cases of human brucellosis were reported in Shandong Province from 2015 to 2020, and the average annual incidence rate was 3.16/100 000. Human brucellosis occurred in every month of the year, and the peak incidence was from March to August, accounting for 66.31% (12 474/18 811). The top 5 counties (districts) with average annual incidence rates were Lijin County (32.39/100 000), Kenli District (11.02/100 000), Wudi County (10.35/100 000), Zhanhua District (9.59/100 000) and Shanghe County (8.80/100 000). There were 13 436 males and 5 375 females, with a male-female sex ratio of 2.50 ∶ 1.00; the age was mainly concentrated in 30-69 years old, accounting for 83.23% (15 656/18 811); farmer was the main occupation, accounting for 85.82% (16 144/18 811). The results of global spatial autocorrelation analysis showed that the annual incidence rates of brucellosis in Shandong Province showed a spatial clustering distribution from 2015 to 2020; and the local spatial autocorrelation analysis showed that the high incidence of human brucellosis was mainly concentrated in the north of Shandong Province.Conclusions:The incidence of brucellosis in Shandong Province is mainly concentrated in spring and summer, most of them are farmers, and the high incidence areas have spatial clustering. Key prevention and control measures should be taken for high incidence seasons, high-risk population and northern high clustering areas to reduce the incidence of brucellosis.

To investigate Streptococcus suis ( S.suis) isolated from patients in Shandong province using genomic epidemiology and pathogenologic analysis. To provide the foundation to establish reasonable and accurate prevention and control measures of human S. suis infection. Molecular typing, whole genome phylogenetic tree, virulence gene typing, antibiotic resistance profile and mobile genetic elements carrying antibiotic resistance genes of isolated S. suis strains were investigated. The pathogenicity of isolated strains was also evaluated by comparing their capacity to induce pro-inflammatory cytokine production in vitro. S. suis infections in Shandong province were predominantly due to serotype 2 and sequence type 1 strains. The major symptoms were meningitis. The studied strains could be divided into five lineages. All strains belong to highly pathogenic type in Shandong province,Strains from lineage 2 possessed higher capacity to stimulate pro-inflammatory cytokine production than other strains did, even though other strains belong to highly pathogenic strains. In addition, multiple antibiotic resistance genes and corresponding mobile genetic elements werewidespread in S. suis strains from Shandong province, except strains from lineage 3. High diversities in genome, evolutionary path and pathogenicity of S. suis strains from Shandong province were revealed. It was necessary to surveillant the S. suis strain in genomic level.

Objective:To establish virus culture method and full genome sequencing method for severe acute respiratory syndrome coronavirus (2019-nCoV), and to illuminate the variation of 2019-nCoV.Methods:The pharyngeal swab specimens were inoculated into Vero-E6 cells for isolation, and the cytopathic effect were observed day by day, and the result of virus isolation were confirmed by Real-Time RT-PCR. Some isolated viruses were diluted 10 times to detect the virus titer. Full-genome of 2019-nCoV was sequenced with the whole genome capture technology and next generation sequencing technology. Phylogenetic analysis and molecular characterization for obtained 2019-nCoV sequences were undertaken.Results:Twenty-two 2019-nCoV strains were isolated with Vero-E6 cell line in the Biosafety Level-3 Laboratory (BSL-3). Eighteen full-genome sequences obtained (almost 29 000 nucleotide) were analyzed with 99.94%~100% identity and 28 nucleotides and 20 amino acids variations. Phylogenetic analysis showed that the 2019-nCoV sequences belonged to different clades, including clade S and clade L with Europe lineage L. I and Europe lineage L. II.1. Furthermore, 5 of 18 2019-nCoV harbor the D614G mutation.Conclusions:2019-nCoV were successfully isolated with Vero-E6 cells, and partially illuminated the phylogenetic characteristics, which provided a basis for subsequent drug screening and biological characteristics research. Continuous monitoring and analysis of the sequences of new cases would be vital to understand the genetic evolution and rates of substitution of the 2019-nCoV.

To investigate Streptococcus suis ( S.suis) isolated from patients in Shandong province using genomic epidemiology and pathogenologic analysis. To provide the foundation to establish reasonable and accurate prevention and control measures of human S. suis infection. Molecular typing, whole genome phylogenetic tree, virulence gene typing, antibiotic resistance profile and mobile genetic elements carrying antibiotic resistance genes of isolated S. suis strains were investigated. The pathogenicity of isolated strains was also evaluated by comparing their capacity to induce pro-inflammatory cytokine production in vitro. S. suis infections in Shandong province were predominantly due to serotype 2 and sequence type 1 strains. The major symptoms were meningitis. The studied strains could be divided into five lineages. All strains belong to highly pathogenic type in Shandong province,Strains from lineage 2 possessed higher capacity to stimulate pro-inflammatory cytokine production than other strains did, even though other strains belong to highly pathogenic strains. In addition, multiple antibiotic resistance genes and corresponding mobile genetic elements werewidespread in S. suis strains from Shandong province, except strains from lineage 3. High diversities in genome, evolutionary path and pathogenicity of S. suis strains from Shandong province were revealed. It was necessary to surveillant the S. suis strain in genomic level.

Objective:To analyze molecular epidemiological characteristics of drug resistance genes and carbapenem resistance of Pseudomonas aeruginosa (PA) in rural well water. Methods:According to Citation of Natural Mineral Water Inspection (GB 8538-2016), a total of 112 well water samples were tested in Juye county of Shandong province, and PFGE and drug susceptibility test were conducted for the identified PA strains. After PCR identification of carbapenem resistance genes, S1-PFGE and Southern blotting were used to determine the location of drug resistance genes, and combined experiments were used to determine gene transferability. Results:The detection rate of PA in rural well water samples in Juye county of Shandong province was 54.46% (61/112). The 61 strains could be divided into 56 PFGE types. There were 2 strains with 100.00% consistent band types, and there was no obvious predominant band type. The results of drug susceptibility experiments showed that 93.44% (57/61) were multi-drug resistant strains, and there were 2 strains carrying blaVIM-2, both of which were located on the plasmid, and both of them were transferred horizontally with the plasmid. Conclusion:PA carrying carbapenem resistance genes was detected in well water of rural communities in Juye country, and there is the possibility of horizontal transmission of such resistance genes.