This study was aimed at determining the genetic characteristics of Yersinia pestis in Subei County through differ-ential region(DFR),clustered regularly interspaced short palindromic repeats(CRISPR),and variable number tandem repeat(VNTR)analyses,to guide the tracing of plague outbreaks.The DNA of 89 Yersinia pestis strains isolated from various ani-mal in foci of Subei County from 1973 to 2017 was extracted.Primers for genotyping by DFR,CRISPR,and MLVA were used in PCR,and agarose electrophoresis was used to determine whether the amplified products were present.Genotypes were deter-mined through comparison against the DFR database of Yersinia pestis in China.The PCR products were sequenced and com-pared against the online CRISPR database for Yersinia pestis to determine the genotype.The number of VNTR repeats in each strain was calculated through capillary electrophoresis,and the minimum spanning tree was constructed with BioNumerics 7.6 according to the numbers of VNTR repeats from 89 Yersinia pestis strains in Subei County and 11 strains from a Marmota hi-malayana focus in Qinghai Province.The Yersinia pestis strains in Subei County were divided into six main genotypes by DFR:8,7,lb,5,32,and 44.The Yersinia pestis strains were divided into three gene clusters and three genotypes by CRISPR.Ca35'was the main gene cluster in Subei County;the genotype was 26';and the distribution was primarily in Dangchengwan Town,Yuerhong Township,and Shibaocheng Township.Ca7 and CaΔ5'comprised secondary gene clusters,with genotypes 22 and 24,and were distributed in Dangchengwan Town,Yuerhong Township,and Shibaocheng Township.The Yersinia pes-tis strains in Subei County were divided primarily into three clusters:the Dangchengwan Machang cluster,Yuerhong Township cluster and Dangchengwan Town cluster.Therefore,the Yersinia pestis strains in Subei County,divided into major and minor genotypes according to DFR,CRISPR and MLVA,showed different regional distribution characteristics,highly diverse geno-types,and complex population characteristics.These aspects are particularly important in tracing the sources of plague out-breaks.

This study was aimed at preliminarily investigating the genetic and antimicrobial resistance characteristics of Salmonella Alachua isolates through whole-genome analyses.Five Salmonella Alachua isolates from various sources(both hu-man and non-human)were collected and identified.Phenotype and serotype verification,antimicrobial susceptibility testing,and whole-genome sequencing were performed.Virulence genes,antimicrobial resistance genes,and plasmid replicons were predicted according to globally available Salmonella Alachua genomic data.A phylogenetic tree was constructed to explore the genetic background.The first report of Salmonella Alachua in China emerged in Shanghai in 2015,and patients presented pri-marily with diarrhea.The isolates have been found predominantly in the eastern and southern coastal regions.Among the five i-solates analyzed,four belonged to sequence type(ST)2061,and one belonged to ST1298.All isolates were susceptible to most commonly used clinical antibiotics.Whole-genome analyses revealed that two ST2061 strains carried the blaKPC-2 gene,and one ST1298 strain carried the fosA7 gene.Phylogenetic analysis of global Salmonella Alachua populations indicated that the ST2061 clone belonged to the C1 clade,which was closely related to strains from the UK,whereas the ST1298 clone was found in the C4 clade,a globally disseminated fosA 7-positive lineage.This study provides initial insights into the genetic and antimi-crobial resistance characteristics of Salmonella Alachua in China,highlighting the presence of strains carrying blaKPC-2 and fo-sA7 genes.These findings may provide a reference for future large-scale molecular epidemiological surveillance and source-trac-ing efforts,and they underscore the importance of enhanced resistance monitoring for Salmonella Alachua.

The aim of this study was to understand the internal genetic diversity and population history dynamics of ticks in Inner Mongolia,to provide data for designing effective vector control programs and revealing ticks'transmission mechanisms.From 2022 to 2023,the manual collection method was used to collect samples in Inner Mongolia.The 16S rDNA and COI gene sequences of ticks were used to identify Hyalomma marginatum,Haemaphysalis concinna,and Argas persicus,and analyze the sequence characteristics and genetic diversity within the populations.Base composition analysis indicated that the average A+T content of the 16S rDNA gene and CO I gene in the three ticks was significantly higher than that of C+G.Moreover,22 haplotypes of the COI gene and 12 haplotypes of the 16S rDNA sequence were identified in Hyalomma marginatum.Eleven haplotypes were identified according to the COI gene,and nine haplotypes were identified according to the16S rDNA sequence of Haemaphysalis concinna.Two haplotypes were identified on the basis of the COI gene,and six haplotypes were identified on the basis of the 16S rDNA sequence of Ar gas persicus.The minimum 16S rDNA haplotype diversity was 0.264 for Ar gas persicus and 0.579 for the other two species.The nucleotide diversity of the three tick species was less than 0.05.Tajima's val-ue and Fu's Fs value of the neutrality test were negative.Base saturation substitution analysis indicated that neither of the two genes in the three tick species reached saturation.The phylogenetic tree revealed that Hyalomma marginatum,Haema physalis concinna,and Ar gas persicus in Inner Mongolia independently aggregated into branches.In conclusion,the base content of Hyalomma marginatum,Haemaphysalis concinna,and Argas persicus genes in Inner Mongolia was consist-ent with the characteristics of insect mitochondrial DNA content.Furthermore,the three tick populations showed rapid evolu-tionary population expansion,and the phylogeny of three tick species showed independent aggregation into clades,with no pop-ulation isolation.

Culicoides Latreille is among the most diverse and numerous genera of blood-sucking midges,and is widely dis-tributed throughout the world.In addition to stinging and harassing humans and animals,it can also transmit a variety of infec-tious diseases in humans and animals,including African horse fever virus(AHSV),blue tongue virus(BTV),and Japanese encephalitis virus(JEV).Therefore,this insect is an important arbovirus vector of medical concern.Scientific monitoring and timely understanding of the population composition,density,and seasonal fluctuation are the basic premise for effective control of blood-sucking midges.In recent years,studies have increasingly assessed the ecological habits and monitoring methods of blood-sucking midges worldwide.This article reviews the frequently used monitoring methods for blood sucking midges world-wide,to provide a reference for monitoring midge density in China.The main methods include CDC light traps,CO2-baited CDC traps,CO2-baited CDC traps without light bulbs,Onderstepoort Veterinary Institute traps,BG-sentinel traps,human landing catch,human net trapping,animal enclosure traps,animal-baited trapping,sweep netting for adult monitoring,the saturated saline flotation method,the Berlese funnel method,and emergence traps for larval monitoring.The methods'operat-ing procedures,applicable monitoring scope,and advantages and limitations are described to provide ideas for promoting the development and improvement of monitoring technology and instruments.In addition,the monitoring methods described here-in,such as the CDC light trap method,sweep netting,and human landing catch,are applicable to monitoring and collecting other midge insects.

Older critically ill patients with tuberculosis may have multiple organ involvement and rapid disease progression,and often have high mortality.Consequently,high-risk patients must be identified early to receive aggressive treatment.The purpose of this study was to investigate the correlation between serum inflammatory factors and prognosis in older critically ill patients with tuberculo-sis,to provide a diagnosis and treatment basis for clinicians,and to facilitate early intervention for patients with poor prognosis.SPSS software was used to analyze data for 172 patients included in the study(82 patients in the survival group and 90 patients in the death group).Univariate analysis indicated significantly higher levels of IL-6,IL-1β,TNF-α,IL-8,IL-17,IL-12P70,IFN-γ,and IL-10 in the death group than the survival group(P<0.05).Multivariate logistic regression analysis demonstrated that IL-6(OR=1.002,95%CI:1.000-1.003,P=0.021),TNF-α(OR=1.175,95%CI:1.034-1.335,P=0.013),and IFN-γ(OR=1.008,95%CI:1.001-1.015,P=0.036)were independent risk factors,and the AUC of the three combined factors in predicting critical and severe tuberculo-sis prognosis in older patients was 0.771.Serum levels of IL-6,TNF-α,and IFN-γ were closely associated with the occurrence and development of tuberculosis in critically ill older patients.The combined detection of the three factors had a high clinical value for the assessment of prognosis of critically ill older patients with tuberculosis,and might be used to predict death in this patient group.

This study evaluated the potential of OPC-167832 as a new method for the treatment of Mycobacterium fortuitum infec-tion.Drug sensitivity tests were conducted with the broth microdilution method to determine the minimum inhibitory concentration(MIC)of OPC-167832 against standard strains of M.fortuitum and 44 clinical isolates of M.fortuitum.A DprE1 overexpression strain was constructed,and the effect in the MIC of OPC-167832 against M.fortuitum were explored.Intracellular germicidal tests and checkerboard tests were conducted to verify the ability of OPC-167832 to kill intracellular M.fortuitum,and its interaction with five drugs:amikacin,clarithromycin,imipenem,moxifloxacin,and clofazimine.The MIC50 and MIC90 against 44 clinical isolates of M.fortuitum were 0.031 25 μg/mL and 0.062 5μg/mL,respectively.The epidemiological cut-off value(ECOFF)was 0.062 5 μg/mL.Overexpression of DprE1 led to resistance to OPC-167832 in M.fortuitum.After 24 hours of incubation,the intracellular bacterial in-hibition rate of OPC-167832 at a 1 μg/mL concentration was 81.37%,exceeding the 74.05%inhibition rate of amikacin at a 1 μg/mL concentration.OPC-167832 showed strong inhibitory activity against M.fortuitum in vitro and in macrophages,and might provide a promising treatment for M.fortuitum infection.

This study reports a case of pulmonary infection by Pasteurella multocida together with nontuberculous mycobacteria,and the pathogenic characteristics of P.multocida isolated in this case.The patient was a 69 year old woman admitted with bronchiecta-sis and infection.Bacterial culture of bronchoalveolar lavage fluid,tuberculosis culture,and Dano-seq multiple pathogen detection were performed after admission.Drug sensitivity testing and second-generation sequencing were performed on the isolated P.multo-cida strain.Non-tuberculous mycobacteria(M.kansasii)and P.multocida were detected in the bacterial culture and Dano-seq re-sults.The major virulence factors of this P.multocida strain included htrB,rfaE,and msbA,among a total of 21 factors.The resistance genes of this strain included floR,sul2,and FosA3,among ten identified genes.MLST analysis classified the P.multocida strain as ST12.A phylogenetic tree indicated that the strain was homologous to the main epidemic strains in China.A detection scheme combin-ing traditional isolation and cultivation with next-generation sequencing enables rapid and accurate identification of rare pathogens,and provides the necessary antimicrobial susceptibility results,thereby facilitating the accurate diagnosis and treatment of rare dis-eases.

Tuberculosis(TB),a chronic infectious disease caused by infection with the Mycobacterium tuberculosis complex(MTBC),has re-emerged as the leading cause of death from a single infectious agent worldwide.Because of widespread use and mis-use of anti-tuberculosis drugs,the emergence of multidrug-resistant TB(MDR-TB)and extensively drug-resistant TB(XDR-TB)is increasing,thus posing a serious threat to global health.The current problem of drug resistance is a major prevention and treatment challenge;therefore,the search for new drug targets is urgently needed.In recent years,substantial progress has been made in re-search on anti-tuberculosis drug targets and novel therapeutic strategies.Herein,we summarize recent research progress in anti-tuberculosis drug targets,primarily cell wall synthesis,nucleic acid replication and transcription,and energy metabolism.We also provide an overview of research progress regarding two novel therapeutic strategies,to provide a theoretical basis and research ideas for the development of new clinical drugs.

A recombinant adenovirus(rAd)for expression of Mycobacterium tuberculosis(M.tb)c-di-AMP phosphodiesterase CnpB was constructed,and its induced humoral immune response was detected.The codon-optimized gene of M.tb CnpB was cloned into the adenoviral plasmid pcADV.The recombinant plasmid pcADV-CnpB was transfected into HEK293T cells,and expression was detected with Western blot.The recombinant plasmid pcADV-CnpB and the backbone plasmid were co-transfected into HEK293T cells to obtain the recombinant adenovirus rAd-CnpB.rAd-CnpB was amplified in HEK293T cells,and the target protein expression of rAd-CnpB was detected with Western blot and immunofluorescence.Mice were immunized with rAd-CnpB intranasally,and their sera and bronchoalveolar lavage fluid(BALF)were collected.ELISA was used to detect levels of antigen-specific antibodies.Restriction enzyme digestion and sequencing indicated that the recombinant plasmid pcADV-CnpB was successfully constructed and led to protein expression in eukaryotic cells.rAd-CnpB was packaged and produced in HEK293T cells.After amplification and purification,rAd-CnpB with a titer of 5.53×1010 PFU/mL was obtained.rAd-CnpB led to CnpB expression in HEK293T cells.Intranasal immunization with rAd-CnpB increased levels of IgG and secretory IgA in BALF and led to high levels of IgG in sera.rAd-CnpB,the recombinant adenovirus for expression of c-di-AMP phosphodiesterase CnpB was successfully constructed,and was found to induce antigen-specific humoral and mucosal immune responses through mucosal immunization.Thus,rAd-CnpB may be used in further research on new TB vaccine strategies.

This study assessed the role and mechanism of the recombinant Bacillus Calmette-Gue?rin vaccine(rBCG)with c-di-AMP adjuvant in regulating metabolism and immunity in epididymal white adipose(eWAT)in mice.Male C57BL/6 mice were intravenously immunized with BCG and rBCG,and their body weights were monitored.eWAT was isolated from the mice,and the stromal vascular fractions(SVFs)cell number was counted with a hemocytometer.Sections of mouse adipose tissue were prepared,and the size,number,and morphology of eWAT adipocytes and crown-like structure(CLS)formation were compared under a microscope after HE staining.The transcription levels of lipid metabolism-associated factors,cytokines and aging-associated genes in each group were determined with qRT-PCR.The body weights of mice gradually increased after immunization with BCG and rBCG.The proportions of eWAT increased,and the SVFs cell number decreased,in rBCG immunized mice.HE staining indicated that BCG immunization promoted hyperplasia,whereas rBCG immunization promoted hypertrophy of eWAT adipocytes;moreover,both BCG and rBCG immunization induced CLS formation in eWAT.The qRT-PCR results indicated that rBCG immunization inhibited the expression of genes associated with lipolysis and energy expenditure in eWAT.BCG immunization had little effect on cytokine transcription,whereas rBCG significantly induced the transcription of IFN-γ and IL-1Ra,and inhibited that of IL-15 and IL-2,but did not induce the expression of aging-associated genes.Thus,rBCG immunization induced eWAT adipocyte hypertrophy,which was associated with the inhibition of eWAT lipolysis and the regulation of cytokine expression.