To perform the phylogenetic characterization of an isolated porcine rotavirus(PoRV)and investigate its pathogenicity in suckling mice and piglets.A G4P[23]genotype PoRV strain JSJR2023 was successfully isolated from the diarrheic piglet feces through propagation in MA104 cells.The viral proliferation kinetics were analyzed using TCID50 assays,followed by complete genome sequencing through Sanger sequencing platforms.Comprehensive genotyping and phylogenetic reconstruction were conducted using MEGA7.0 with maximum likelihood algorithms.Pathogenicity was assessed in the following animal models:5-day-old C57BL/6 mice and 3-day-old piglets.Multidimensional evaluation included clinical monitoring(diarrhea scoring,growth parameters),virological detection,and histopathological analysis of intestinal tissues.The virus strain JSJR2023 could replicate efficiently in MA104 cells,achieving peak titers of 107.5 TCID50/mL.Whole genome genotype analysis showed that the strain belonged to G4-P[23]-I5-R1-C1-M1-A8-N1-T1-E1-H1.Phylogenetic analysis indicated that the VP3 and NSP4 genes of JSJR2023 strain were most closedrelated to human species rotaviruses,suggesting genetic reassortment between human and porcine RV strains.The animal experiments in suckling mice showed that the JSJR2023 strain infection caused diarrhea symptoms,intestinal edema and congestion,and shedding of intestinal villus epithelial cells.The pathogenicity experiments in piglets showed that compared with the control group,the challenged group of pig-lets had severe diarrhea symptoms,accompanied by reduced appetite and listlessness.Post-mortem examination revealed that the intes-tines were significantly thinner,congested,and filled with yellow watery contents.The challenged piglets showed typical pathological changes such as thinning of the intestinal wall and shortening and shedding of intestinal villi.In conclusion,this study successfully iso-lated a human-porcine recombinant G4P[23]PoRV strain and established the infection models in suckling mice and piglets,providing important tools for investigating the pathogenic mechanism of PoRV,evaluating vaccines and developing antiviral drug.

Japanese encephalitis virus(JEV)belongs to the genus Flavivirus and the family Flavi-viridae,and is classified as a single-stranded,positive-sense RNA virus.The disease known as Japa-nese encephalitis(JE),which results from JEV infection,is a viral zoonosis that is prevalent worldwide and poses a significant public health concern.JEV infection activates a variety of signa-ling pathways,leading to a series of changes that are crucial to the virus's pathogenesis.Among these pathways,Toll-like receptors(TLRs)are particularly significant,and their diverse range and complex signal transduction mechanisms present substantial challenges for the prevention and con-trol of JEV.Currently,there is no specific treatment for JEV.Although some vaccines have been developed to prevent JE,eradicating JEV remains difficult due to its zoonotic transmission cycle and the limited efficacy of the available vaccines.This article reviews the alterations in various TLR signaling pathways induced by JEV infection in the host,aiming to provide insights into the patho-genic mechanisms of JEV and to identify potential new antiviral targets.

Porcine reproductive and respiratory syndrome virus(PRRSV)is the pathogen of porcine reproductive and respiratory syndrome(PRRS),and its infection mainly causes abortion,stillbirth in sows and piglet respiratory infections,which are widely prevalent in the world and seriously jeopardize the development of the world's animal husbandry industry.PRRSV infection of the host is capable of inducing significant immunosuppression,and in recent years,the study of the mecha-nism of PRRSV immunosuppression has become a hot topic,with studies showing that numerous PRRSV proteins are involved in the regulation of host innate immunity and elucidating the mecha-nism by which PRRSV proteins modulate host innate immunity.In this paper,we reviewed the progress of research on the interaction mechanism between PRRSV proteins and host innate im-munity to provide a theoretical basis for a comprehensive understanding of the pathogenesis of PRRSV and the prevention and control of PRRS.

BACKGROUND:Studies have shown that vascular factors have an important impact on the occurrence of diabetic foot.OBJECTIVE:To investigate the important role of angiopoietin-like protein 4 in the formation of diabetic foot.METHODS:(1)Bioinformatics analysis was performed on the gene expression profile data of diabetic foot patients to find the key genes.The skin samples of diabetic foot patients and healthy people were collected for hematoxylin-eosin staining,immunohistochemical staining,and qRT-PCR experiments to detect the expression of angiopoietin-like protein 4.(2)The immortalized human skin fibroblast cell line and primary human umbilical vein endothelial cells were cultured.The two kinds of cells were divided into control group and exogenous angiopoietin-like protein 4 supplemented group.The migration ability and proliferation ability of fibroblasts were detected by scratch assay and CCK-8 assay.The proliferation ability of endothelial cells was detected by Ki67 assay.RESULTS AND CONCLUSION:(1)Bioinformatics analysis results showed that the down-regulation of angiopoietin-like protein 4 gene might be the key gene leading to the formation of diabetic foot.(2)Hematoxylin-eosin staining exhibited that compared with normal skin,angiopoietin-like protein 4 was weakly expressed in diabetic foot skin,and the mRNA level was decreased(P＜0.01).(3)Scratch assay results demonstrated that compared with the control group,fibroblast migration ability was significantly enhanced in the angiopoietin-like protein 4 group.CCK-8 assay showed that the absorbance value of fibroblasts in the angiopoietin-like protein 4 group was higher than that of the control group at 24 and 48 hours(P＜0.01,P＜0.001).It is suggested that angiopoietin-like protein 4 can enhance the migration and proliferation of fibroblasts.(4)Ki67 assay results demonstrated that the number of Ki67 positive cells in the angiopoietin-like protein 4 group was significantly more than that in the control group.CCK-8 assay results showed that the absorbance value of endothelial cells in the angiopoietin-like protein 4 group was higher than that of the control group at 24 and 48 hours(P＜0.05,P＜0.001).(5)All findings suggest that angiopoietin-like protein 4 can enhance the proliferation of endothelial cells treated with high glucose.

To perform the phylogenetic characterization of an isolated porcine rotavirus(PoRV)and investigate its pathogenicity in suckling mice and piglets.A G4P[23]genotype PoRV strain JSJR2023 was successfully isolated from the diarrheic piglet feces through propagation in MA104 cells.The viral proliferation kinetics were analyzed using TCID50 assays,followed by complete genome sequencing through Sanger sequencing platforms.Comprehensive genotyping and phylogenetic reconstruction were conducted using MEGA7.0 with maximum likelihood algorithms.Pathogenicity was assessed in the following animal models:5-day-old C57BL/6 mice and 3-day-old piglets.Multidimensional evaluation included clinical monitoring(diarrhea scoring,growth parameters),virological detection,and histopathological analysis of intestinal tissues.The virus strain JSJR2023 could replicate efficiently in MA104 cells,achieving peak titers of 107.5 TCID50/mL.Whole genome genotype analysis showed that the strain belonged to G4-P[23]-I5-R1-C1-M1-A8-N1-T1-E1-H1.Phylogenetic analysis indicated that the VP3 and NSP4 genes of JSJR2023 strain were most closedrelated to human species rotaviruses,suggesting genetic reassortment between human and porcine RV strains.The animal experiments in suckling mice showed that the JSJR2023 strain infection caused diarrhea symptoms,intestinal edema and congestion,and shedding of intestinal villus epithelial cells.The pathogenicity experiments in piglets showed that compared with the control group,the challenged group of pig-lets had severe diarrhea symptoms,accompanied by reduced appetite and listlessness.Post-mortem examination revealed that the intes-tines were significantly thinner,congested,and filled with yellow watery contents.The challenged piglets showed typical pathological changes such as thinning of the intestinal wall and shortening and shedding of intestinal villi.In conclusion,this study successfully iso-lated a human-porcine recombinant G4P[23]PoRV strain and established the infection models in suckling mice and piglets,providing important tools for investigating the pathogenic mechanism of PoRV,evaluating vaccines and developing antiviral drug.

To identify clinical viral diseases characterized by reproductive disorders and abortion,a quadruple qPCR method was established for simultaneous detection of PRV,PPV,PCV2 and AS-FV.Four pairs of specific primers and probes were designed according to the conserved genes of four viruses in the NCBI gene bank.The annealing temperature,primer concentration and probe concentration of the reaction were optimized,and the specificity,sensitivity and repeatability of the method were tested.The results showed that the method could not detect other pathogens except the target ones.The minimum detection limit of PRV,PPV,PCV2 and ASFV was 10 copies.Intra-group and inter-group repeatability tests showed that the coefficient of variation of C,values be-tween different batches was less than 3％,indicating that the method was highly specific,sensitive and stable.Establishment of an efficient and sensitive quadruple qPCR method provides technical reference for the clinical prevention and control of porcine pseudorabies virus disease,porcine circo-virus disease,porcine parvovirus disease and African swine fever.

This study investigates the effects of pseudorabies virus(PRV)infection on the antiviral immune signaling pathways and type Ⅰ interferon factors in mouse trigeminal ganglion(TG)cells.In this experiment,primary TG cells were infected with PRV at a multiplicity of infection(MOI)of 1,while mice were infected via a drop-nose method using 106,29 TCID50 of PRV.Real-time fluorescence quantitative PCR(qPCR),Western blot and ELISA were used to assess gene tran-scription,protein expression,and the secretion of IFN-α and IFN-β.The results indicated that PRV infection of mouse TG primary cells led to alterations in the gene and protein expression of RIG-Ⅰ,MAVS,and IRF3,as well as the phosphorylation of IRF3 and IKBα both in vivo and ex vivo.ELISA results showed that PRV infection could regulate the secretion of IFN-α and IFN-β in mouse primary TG cells and mouse TGs.The results of RIG-Ⅰ signaling pathway-related proteins and the secretion of IFN-a and IFN-β were analyzed using Western blot after using siRNA to interfere with RIG-Ⅰ expression in TG cells.The results showed that siRIG-Ⅰ successfully inter-fered with RIG-Ⅰ protein expression in TG cells and caused changes in the expression of down-stream proteins such as MAVS and IRF3,and also regulated the secretion of IFN-α and IFN-β in TG cells.Furthermore,the results indicated that PRV infection induced the expression of RIG-Ⅰ in mouse TG progenitor cells,regulating the antiviral immune response of type Ⅰ interferon factors in TG cells through the RIG-Ⅰ-MAVS-IRF3 signaling axis.Notably,PRV inhibited the expression of IRF3 in TG cells while significantly upregulating the expression of IFN-β during the later stages of infection,which may be an important factor in the important reason for the rapid mortality ob-served in mice during the late stages of PRV infection.This experiment elucidates part of the anti-viral immune mechanism mediated by the RIG-Ⅰ-MAVS-IRF3 signaling pathway in regulating type Ⅰ interferon factor after PRV infection of mouse TG cells,as well as the discovery of differ-ent trends of IRF3 protein changes in vivo and ex vivo,laying the groundwork for future in-depth studies.

Porcine deltacoronavirus(PDCoV)is the main pathogen of porcine deltacoronavirus dis-ease.After infection,pigsmanifest a series of main symptoms,such as persistent vomiting,watery diarrhea and severe dehydration.Pigs at almost all growth stages are likely to be infected with the virus,especially suckling piglets are much sensitive to the virus.Once PDCoV infects the host,it u-sually causes significant immunosuppression.In recent years,studies on the immunosuppressive mechanism of PDCoV have gradually attracted widespread attention.The results showed that mul-tiple proteins of PDCoV were involved in the regulation of host innate immunity,revealing the mechanism of these proteins in regulating host innate immunity.In this paper,the interaction mechanism between PDCoV protein and host innate immunity were rsummarized,which will pro-vide a theoretical basis for further understanding the pathogenesis of PDCoV and effective preven-tion and control of porcine delta coronavirus disease.

To establish a TaqMan-based multiplex RT-qPCR method for the identification of Japa-nese encephalitis virus(JEV),Porcine reproductive and respiratory syndrome virus(PRRSV),and Classical swine fever virus(CSFV),this study designed and synthesized three pairs of specific primers and probes based on the conserved sequences of JEV E,PRRSV ORF6,and CSFV E2 a-vailable in the NCBI GenBank.By optimizing the reaction system and protocol,a multiplex RT-qPCR method for detecting these three viruses was developed and applied to the detection of clini-cal samples.The results showed that the established TaqMan multiplex RT-qPCR specifically am-plified the gene fragments of JEV,PRRSV,and CSFV,and did not amplify other non-target genes,indicating good specificity of the method.Intra-assay and inter-assay repeatability tests showed that the coefficient of variation(Cv)values were all below 3％,demonstrating that the method has ex-cellent repeatability.Sensitivity tests revealed that the minimum detectable amount for the recom-binant plasmids of the three viruses was 100 copies/pL.Using the established method,a total of 969 samples,including blood,aborted fetuses,semen,and deceased pigs,from 26 pig farms in Guizhou Province were tested.The detection rates were 34.3％(332/969)for JEV,28.3％(274/969)for PRRSV,and 19.8％(192/969)for CSFV.The co-infection rates were 10.1％(98/969)for JEV and PRRSV,12.1％(117/969)for JEV and CSFV,and 14.6％(141/969)for CSFV and PRRSV.Additionally,the triple co-infection rate of JEV,PRRSV,and CSFV was 7.9％(77/969).These results indicate that the TaqMan multiplex RT-qPCR method developed in this study is ef-fective for detecting these three viruses in pig farms,providing technical support for identifying vi-ral causes of reproductive disorders.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.