To elucidate the genomic characteristics of Salmonella strains derived from sheep,this study employed various methods,including bacterial isolation and identification,biochemical identi-fication,pathogenicity test,whole-genome sequencing,and BLAST comparison,along with the screening of integrative conjugative elements(ICE)using ICEfinder and EasyFig for comparative analysis,as well as plasmid comparisons utilizing PlasmidBrig.The results revealed the isolation of a Gram-negative,non-spore-forming bacillus from nasal swabs of diseased sheep,which formed gray-white,smooth-surfaced,and neatly edged circular colonies on TSA sheep blood agar.On XLT-4 agar medium,it produced smooth-surfaced,white,circular colonies.The bacterium was identified as Salmonella enterica through 16S rRNA sequencing and biochemical identification.This bacteri-um induces hemorrhaging in the intestines of guinea pigs,resulting in their demise within a 48-hour period.The pathogen exhibits high virulence.Whole-genome alignment demonstrated a high degree of homology with Salmonella enterica subsp.diarizonae serotype 61:k:1,5,(7).ICE screen-ing and comparative analysis indicated the presence of a novel ICE in this strain,characterized by a core structural framework that includes an integrative shear module,a mobilizable processing mod-ule,a conjugative pair formation module,and a regulatory module.Notably,ICE from different spe-cies containing the same integrase exhibited identical inverted repeat sequences and insertion sites at tRNAPhe.Plasmid homology comparisons revealed that plasmid sequences from different strains of Salmonella enterica subsp.diarizonae serotype 61:k:1,5,(7)also showed high homology;however,the homology with plasmid sequences from other Salmonella and Escherichia coli strains was only 50％.These findings indicate that the isolated strain is Salmonella enterica subsp.diarizonae serotype 61:k:1,5,(7)and contains a novel ICE as well as a plasmid.This study fur-ther enriches the molecular epidemiology of Salmonella and provides a theoretical basis for the prevention and control of infections caused by this pathogen.

pAPN is a zinc-dependent metalloprotease,mediating the fusion between virus and host cell,and playing a role as the receptor of coronavirus.To explore the effect of pAPN on PEDV rep-lication,the full-length pAPN gene was amplified from the porcine small intestinal by PCR,and was cloned into the lentiviral vector via the homologous site digested with BamH Ⅰ and Not Ⅰ to obtain the recombinant lentiviral vector PLVX-pAPN-mCMV-ZsGreen1-puro.The recombinant lentiviral vector and helper plasmids pLP1,pLP2,pLP-VSVG were co-transfected into 293T cells for lentiviral packaging.Vero cells were infected with the packaged lentivirus and the pAPN gene overexpressing cells were screened by puromycin.The stable expression of Vero-pAPN monoclonal cell line was screened by a limited dilution method,and the effect of the cell line on the replication of PEDV was determined by qPCR for N mRNA transcription level,Western blot for N protein level,and TCID50.The results showed that the packaged lentivirus could infect Vero cells,and the monoclonal cell line Vero-pAPN(2C5)could stably expressed pAPN.The Vero-pAPN cell line can promote the replication of PEDV,the N gene mRNA transcription level was significantly different at 12-48 h(P＜0.05),the N protein expression level increased,and the TCID50 was significantly different at 24 and 48 h(P＜0.05).In conclusion,the Vero-pAPN cell line was constructed in this study and it can significantly promote the replication of PEDV,which provides a candidate cell line for PEDV vaccine production and isolation.

To elucidate the genomic characteristics of Salmonella strains derived from sheep,this study employed various methods,including bacterial isolation and identification,biochemical identi-fication,pathogenicity test,whole-genome sequencing,and BLAST comparison,along with the screening of integrative conjugative elements(ICE)using ICEfinder and EasyFig for comparative analysis,as well as plasmid comparisons utilizing PlasmidBrig.The results revealed the isolation of a Gram-negative,non-spore-forming bacillus from nasal swabs of diseased sheep,which formed gray-white,smooth-surfaced,and neatly edged circular colonies on TSA sheep blood agar.On XLT-4 agar medium,it produced smooth-surfaced,white,circular colonies.The bacterium was identified as Salmonella enterica through 16S rRNA sequencing and biochemical identification.This bacteri-um induces hemorrhaging in the intestines of guinea pigs,resulting in their demise within a 48-hour period.The pathogen exhibits high virulence.Whole-genome alignment demonstrated a high degree of homology with Salmonella enterica subsp.diarizonae serotype 61:k:1,5,(7).ICE screen-ing and comparative analysis indicated the presence of a novel ICE in this strain,characterized by a core structural framework that includes an integrative shear module,a mobilizable processing mod-ule,a conjugative pair formation module,and a regulatory module.Notably,ICE from different spe-cies containing the same integrase exhibited identical inverted repeat sequences and insertion sites at tRNAPhe.Plasmid homology comparisons revealed that plasmid sequences from different strains of Salmonella enterica subsp.diarizonae serotype 61:k:1,5,(7)also showed high homology;however,the homology with plasmid sequences from other Salmonella and Escherichia coli strains was only 50％.These findings indicate that the isolated strain is Salmonella enterica subsp.diarizonae serotype 61:k:1,5,(7)and contains a novel ICE as well as a plasmid.This study fur-ther enriches the molecular epidemiology of Salmonella and provides a theoretical basis for the prevention and control of infections caused by this pathogen.

pAPN is a zinc-dependent metalloprotease,mediating the fusion between virus and host cell,and playing a role as the receptor of coronavirus.To explore the effect of pAPN on PEDV rep-lication,the full-length pAPN gene was amplified from the porcine small intestinal by PCR,and was cloned into the lentiviral vector via the homologous site digested with BamH Ⅰ and Not Ⅰ to obtain the recombinant lentiviral vector PLVX-pAPN-mCMV-ZsGreen1-puro.The recombinant lentiviral vector and helper plasmids pLP1,pLP2,pLP-VSVG were co-transfected into 293T cells for lentiviral packaging.Vero cells were infected with the packaged lentivirus and the pAPN gene overexpressing cells were screened by puromycin.The stable expression of Vero-pAPN monoclonal cell line was screened by a limited dilution method,and the effect of the cell line on the replication of PEDV was determined by qPCR for N mRNA transcription level,Western blot for N protein level,and TCID50.The results showed that the packaged lentivirus could infect Vero cells,and the monoclonal cell line Vero-pAPN(2C5)could stably expressed pAPN.The Vero-pAPN cell line can promote the replication of PEDV,the N gene mRNA transcription level was significantly different at 12-48 h(P＜0.05),the N protein expression level increased,and the TCID50 was significantly different at 24 and 48 h(P＜0.05).In conclusion,the Vero-pAPN cell line was constructed in this study and it can significantly promote the replication of PEDV,which provides a candidate cell line for PEDV vaccine production and isolation.

Objective: To investigate the correlation between the feature of lobulation, degree of lobulation on CT images and epidermal growth factor receptor gene (EGFR) mutations in advanced pulmonary adenocarcinoma. Methods: Two hundred and one patients who were diagnosed with advanced pulmonary adenocarcinoma between January and December 2017 and had undergone a chest CT and EGFR mutation testing at Shanghai Pulmonary Hospital were enrolled in this retrospective study. The clinical and imaging data of the patients were analyzed. The patients were classified into EGFR mutations group (107 cases) and wild type group (94 cases) according to whether EGFR gene mutation occurred. The feature of lobulation (described as presence of lobulation, absence of lobulation, or obscured margin), degree of lobulation (including deep lobulation, shallow lobulation, no lobulation, and obscured) on CT images were statistically compared between the two groups. Results: Based on the presence or absence of lobulation sign, there were 99, 0, 8 cases with lobulation, no lobulation, obscured margin in the EGFR mutations group and 80, 1, 13 cases in the wild type group, respectively. There was no significant difference in lobulation sign between the EGFR mutations group and wild type group (P=0.152). According to the degree of lobulation, there were 32, 67, 0, 8 cases of deep lobulation, shallow lobulation, no lobulation, obscured margin in EGFR mutations group and 60, 20, 1, 13 cases in wild type group. Significant differences of frequency were found regarding deep lobulation and shallow lobulation between the two groups (P<0.001). However, there was no significant difference between the two groups in the presence of no lobulation, and obscured margin (P>0.05). Conclusions EGFR mutations are significantly associated with shallow lobulation in advanced pulmonary adenocarcinoma. Conversely, deep lobulation is more likely to appear in advanced pulmonary adenocarcinoma with wild-type EGFR. However, there is no association between EGFR mutation status and the presence of lobulation.

Objective To investigate the correlation between the feature of lobulation, degree of lobulation on CT images and epidermal growth factor receptor gene (EGFR) mutations in advanced pulmonary adenocarcinoma. Methods Two hundred and one patients who were diagnosed with advanced pulmonary adenocarcinoma between January and December 2017 and had undergone a chest CT and EGFR mutation testing at Shanghai Pulmonary Hospital were enrolled in this retrospective study. The clinical and imaging data of the patients were analyzed. The patients were classified into EGFR mutations group (107 cases) and wild type group (94 cases) according to whether EGFR gene mutation occurred. The feature of lobulation (described as presence of lobulation, absence of lobulation, or obscured margin), degree of lobulation (including deep lobulation, shallow lobulation, no lobulation, and obscured) on CT images were statistically compared between the two groups. Results Based on the presence or absence of lobulation sign, there were 99, 0, 8 cases with lobulation, no lobulation, obscured margin in the EGFR mutations group and 80, 1, 13 cases in the wild type group, respectively. There was no significant difference in lobulation sign between the EGFR mutations group and wild type group (P=0.152). According to the degree of lobulation, there were 32, 67, 0, 8 cases of deep lobulation, shallow lobulation, no lobulation, obscured margin in EGFR mutations group and 60, 20, 1, 13 cases in wild type group. Significant differences of frequency were found regarding deep lobulation and shallow lobulation between the two groups (P<0.001). However, there was no significant difference between the two groups in the presence of no lobulation, and obscured margin (P>0.05). Conclusions EGFR mutations are significantly associated with shallow lobulation in advanced pulmonary adenocarcinoma. Conversely, deep lobulation is more likely to appear in advanced pulmonary adenocarcinoma with wild?type EGFR. However, there is no association between EGFR mutation status and the presence of lobulation.