The aim of this paper was to investigate the serotypes,virulence factors and drug resist-ance of clinical isolates of Pasteurella rnultocida of porcine origin in recent years.Morphological screening and polymerase chain reaction(PCR)were used to isolate and identify 119 isolates from nasal swabs and lung tissue samples sent from swine farms in Zhejiang Province from 2010 to 2024.The isolates of Pasteurella multocida were subjected to capsular polysaccharide serotyping,lipopolysaccharide serotyping,virulence factor detection and drug resistance analysis by PCR and Kirby-Bauer disc agar diffusion method(K-B).The results showed that there were 64 strains(53.7％)of A-type,54 strains(45.3％)of D-type and 1 strain(0.9％)of F-type among the capsu-lar polysaccharide serotypes,and 10 strains(8.4％)of L1-type,20 strains(16.8％)of L3-type,86 strains(72.2％)of L6-type,and 3 strains(2.6％)of undetermined type among the lipopolysaccha-ride serotypes.The amplification results of 10 virulence genes showed that the detection rate of virulence genes hgbA,higbB and fimA was over 86.0％,the detection rate of toxA was 8.4％,while the virulence gene tbpA was not detected.There were also differences in the distribution vir-ulence genes in different capsular polysaccharide serotypes.Virulence factor pfhA was detected in type A and F but not in type D.The detection rate of adhesin gene tadD in serotype A(92.2％)was significantly higher than that of type D(9.3％),and,on the contrary,the detection rate of ad-hesin gene hsf-l in serotype D(90.7％)was significantly higher than that of type A(20.3％).Drug resistance analysis revealed that Pasteurella multocida showed high susceptibility to antimi-crobial drugs such as amoxicillin,ampicillin,cephalosporins,doxycycline,fosfenicol and ciprofloxa-cin,and showed strong resistance to antimicrobial drugs such as lincomycin,cotrimoxazole,genta-micin and amikacin,and there were 54 multi-drug resistant strains(78.3％).In summary,capsular polysaccharide serotypes were dominated by type A and D,lipopolysaccharide serotypes were dom-inated by L6,the distribution of some virulence genes varied greatly among different serotypes,and the proportion of multi-resistant strains was high,which provide reference for the prevention and control of this disease.

Objective To identify potential quality risks of Xiaoer Huatan Zhike Granules(Pediatric Phlegm-Resolving and Cough-Relieving Granules)through National Drug Sampling and Inspection,evaluate their overall quality,and propose improvements to the quality standards.Methods Samples from 34 manufacturers were tested using official standards.Exploratory methods were developed to enhance risk analysis,including thin-layer chromatography(TLC)identification,content uniformity testing,quantitative assays,and screening for unauthorized additives(e.g.,colorants).Results All batches met the official standards(100.0%compliance rate).However,deficiencies were observed:most manufacturers lacked controls for ephedrine hydrochloride content uniformity and quantification,omitted key ingredient identifications(e.g.,herbal components),and exhibited insufficient TLC specificity(e.g.,TLC of Ipecac tincture showed only one spot instead of multiple alkaloid-specific spots).Exploratory studies revealed risks in total emetine/cephaeline content,morroniside A/platycodin D content,ephedrine hydrochloride uniformity,and unauthorized colorant addition.Conclusions The overall quality of this variety is good,but the enterprise should improve the quality control measures throughout the entire process and establish stricter internal control standards;The official standards,unchanged for approximately 30 years,fail to address current regulatory requirements.The statutory quality standards need to be revised and improved.Qualitative or quantitative indicators for all drug flavors in the prescription should be added,and the content uniformity inspection of ephedrine hydrochloride should be increased.

Objective To observe imaging manifestations of spinal chronic osteomyelitis.Methods Totally 56 patients with spinal chronic osteomyelitis were retrospectively enrolled,including 18 cases complicated with synovitis,acne,pustulosis,hyperostosis and osteomyelitis(SAPHO)syndrome while 38 cases did not.CT and MRI manifestations were observed.Results Among 56 cases,cervical spine involvement was observed in in 25 cases(25/56,44.64％).Single spine segment involvement,2 segments involvements and 3 or more segments involvements were found in 17(17/56,30.36％),18(18/56,32.14％)and 21 cases(21/56,37.50％),respectively.The ratio of 3 or more segments involvements in 18 cases with SAPHO syndrome was 61.11％(11/18),while in 38 cases without SAPHO syndrome was 26.32％(10/38),the former was higher than the latter(P＜0.05).Meanwhile,16 cases(16/56,28.57％)complicated with compression fracture,30(30/56,53.57％)with hyperosteogeny,22(22/56,39.29％)with paraspinal soft tissue swelled and 15(15/56,26.79％)with extra spinal involvements.The ratio of extra spinal involvement in patients with and without SAPHO syndrome was 72.22％(13/18)and 5.26％(2/38),respectively,the former was higher than the latter(P＜0.05).Conclusion Imaging manifestations of spinal chronic osteomyelitis had certain characteristics.In patients complicated with SAPHO syndrome,3 or more segments of spine involvements were common,with more extra spinal involvements.

Objective To explore the differential diagnosis of middle cerebral artery(MCA)embolic infarction and perforating artery infarction based on 3.0T vessel wall magnetic resonance imaging(VW-MRI)characteristics of the head and neck.Methods The data of 148 patients with MCA infarction were retrospectively analyzed.According to the infarction sites,all patients were divided into non-perforating artery infarction group(n=77)and perforating artery infarction group(n=71).All patients underwent routine MRI and VW-MRI scans.MCA stenosis rate,stenosis degree,remodeling index(RI),remodeling mode and plaque properties were evalu-ated,respectively.Results There was no significant difference in stenosis rate,stenosis degree,RI and remodeling mode between the two groups(P＞0.05),but there were significant differences in incidence of intraplaque hemorrhage and irregular plaques,plaque site and enhancement degree between the two groups(P＜0.05).Conclusion The differences in VW-MRI characteristics of different types of MCA infarction are mainly reflected in plaque properties,which provide useful information for clinical determina-tion of infarction types.

Glaesserella parasuis is the causative agent of Gl?sser's disease in pigs.However,the pathogenic mechanisms underlying its virulence is not yet fully understood.The RuvB protein,a member of the AAA+superfamily,is implicated in various cellular processes,yet its specific role in the virulence of Glaesserella parasuis has not been fully characterized.In this study,we con-structed a RuvB gene deletion mutant,designated ΔRuvB,using the serotype 13 Glaesserella pa-rasuis strain ZJ1208 and a suicide plasmid-mediated natural transformation approach.To elucidate the functional role of the RuvB gene,we comprehensively evaluated the biological characteristics of the ΔRuvB strain through a series of assays,including growth kinetics,colony morphology,bac-terial staining,transmission electron microscopy(TEM),osmotic stress tolerance,high-tempera-ture tolerance,heat shock resistance,UV resistance,capsular polysaccharide quantification,serum bactericidal assays,and murine virulence experiments.Our findings revealed that the growth rate of ΔRuvB showed no significant difference compared to the parental strain.TEM revealed a notable increase in bacterial cell length;however,the number of outer membrane vesicles(OMVs)on the surface of ΔRuvB did not significantly increase.Notably,the ΔRuvB strain displayed a significant reduction in capsular polysaccharide production and serum resistance,as well as diminished toler-ance to UV radiation and high temperatures.Significant alterations were observed in its resistance to osmotic stress or oxidative stress.In the mouse toxicity challenge experiment,in com-parison with the parental strain ZJ1208,the mortality rate dropped by 20 percentage points,suggesting that the virulence of ΔRuvB has been weakened to some extent.Collectively,these results underscore the critical role of the RuvB gene in enhancing the environmental adaptability of Glaesserella parasuis.

Glaesserella parasuis is the causative agent of Gl?sser's disease in pigs.However,the pathogenic mechanisms underlying its virulence is not yet fully understood.The RuvB protein,a member of the AAA+superfamily,is implicated in various cellular processes,yet its specific role in the virulence of Glaesserella parasuis has not been fully characterized.In this study,we con-structed a RuvB gene deletion mutant,designated ΔRuvB,using the serotype 13 Glaesserella pa-rasuis strain ZJ1208 and a suicide plasmid-mediated natural transformation approach.To elucidate the functional role of the RuvB gene,we comprehensively evaluated the biological characteristics of the ΔRuvB strain through a series of assays,including growth kinetics,colony morphology,bac-terial staining,transmission electron microscopy(TEM),osmotic stress tolerance,high-tempera-ture tolerance,heat shock resistance,UV resistance,capsular polysaccharide quantification,serum bactericidal assays,and murine virulence experiments.Our findings revealed that the growth rate of ΔRuvB showed no significant difference compared to the parental strain.TEM revealed a notable increase in bacterial cell length;however,the number of outer membrane vesicles(OMVs)on the surface of ΔRuvB did not significantly increase.Notably,the ΔRuvB strain displayed a significant reduction in capsular polysaccharide production and serum resistance,as well as diminished toler-ance to UV radiation and high temperatures.Significant alterations were observed in its resistance to osmotic stress or oxidative stress.In the mouse toxicity challenge experiment,in com-parison with the parental strain ZJ1208,the mortality rate dropped by 20 percentage points,suggesting that the virulence of ΔRuvB has been weakened to some extent.Collectively,these results underscore the critical role of the RuvB gene in enhancing the environmental adaptability of Glaesserella parasuis.

Objective:To construct a sizeable naive human Fab phage display antibody library to screen high-affinity specific antibodies in vitro. Methods:Total RNA was extracted from peripheral blood mononuclear cells (PBMCs) of 126 healthy individuals, subsequently reverse-transcribed into cDNA, and used as a template. PCR amplification was performed to obtain the V H from IgG, IgM and light chain κ, λ, separately, with the initial PCR products serving as templates for a second round of PCR. Overlap extension PCR was employed to generate fragments of the κ and λ light chains. These fragments were ligated with the phage vector pNC3, which harbors the variable region 1 of the heavy chain, to construct a recombinant phage plasmid. This plasmid was then electroporated into competent Escherichia Coli TG1 cells to establish a naive human Fab phage display antibody library. One hundred clones were randomly selected for identification and sequencing, and antibody gene polymorphisms were analyzed using the IMGT database and MAFFT software. Recombinant α-hemolysin from Staphylococcus aureus was utilized to screen Fab antibody fragments through biopanning of the antibody library, followed by random selection of phage ELISA-identified clones. The positive clones (antigen A450∶blank control A450≥2.1) were sequenced. Results:Two large naive Fab phage display antibody libraries were successfully constructed, in which the capacity of κ and λ chain antibody libraries were 1.25×10 11 and 1.54×10 11, respectively. The titers for two antibody libraries were 6.04×10 13 CFU/ml and 3.50×10 13 CFU/ml. The positive transformation insertion rates for κ and λ chain antibody libraries were 96% (96/100) and 100% (100/100), respectively. Sequence analysis revealed that all antibody sequences were unique. The amino acid sequences in the skeletal region were relatively conserved. In contrast, significant variations in the length of the complementarity determining region (CDR) were found, and the diversity of amino acid sequence of the complementary determining region was high, especially the CDR3. Analysis using the IMGT database indicated that the sequences exhibited a broad distribution across variable-diversity-joining gene families. After six rounds of panning, specific phage antibodies enrichment targeting α-hemolysin were achieved. A total of 142 monoclonal antibodies were sequenced, yielding 8 distinct Fab antibody sequences. Conclusion:This study successfully constructed two naive human Fab phage display antibody libraries with large capacity and good diversity, which can be used for screening human antibodies for serum epidemiology.

Objective To explore the differential diagnosis of middle cerebral artery(MCA)embolic infarction and perforating artery infarction based on 3.0T vessel wall magnetic resonance imaging(VW-MRI)characteristics of the head and neck.Methods The data of 148 patients with MCA infarction were retrospectively analyzed.According to the infarction sites,all patients were divided into non-perforating artery infarction group(n=77)and perforating artery infarction group(n=71).All patients underwent routine MRI and VW-MRI scans.MCA stenosis rate,stenosis degree,remodeling index(RI),remodeling mode and plaque properties were evalu-ated,respectively.Results There was no significant difference in stenosis rate,stenosis degree,RI and remodeling mode between the two groups(P＞0.05),but there were significant differences in incidence of intraplaque hemorrhage and irregular plaques,plaque site and enhancement degree between the two groups(P＜0.05).Conclusion The differences in VW-MRI characteristics of different types of MCA infarction are mainly reflected in plaque properties,which provide useful information for clinical determina-tion of infarction types.

The aim of this paper was to investigate the serotypes,virulence factors and drug resist-ance of clinical isolates of Pasteurella rnultocida of porcine origin in recent years.Morphological screening and polymerase chain reaction(PCR)were used to isolate and identify 119 isolates from nasal swabs and lung tissue samples sent from swine farms in Zhejiang Province from 2010 to 2024.The isolates of Pasteurella multocida were subjected to capsular polysaccharide serotyping,lipopolysaccharide serotyping,virulence factor detection and drug resistance analysis by PCR and Kirby-Bauer disc agar diffusion method(K-B).The results showed that there were 64 strains(53.7％)of A-type,54 strains(45.3％)of D-type and 1 strain(0.9％)of F-type among the capsu-lar polysaccharide serotypes,and 10 strains(8.4％)of L1-type,20 strains(16.8％)of L3-type,86 strains(72.2％)of L6-type,and 3 strains(2.6％)of undetermined type among the lipopolysaccha-ride serotypes.The amplification results of 10 virulence genes showed that the detection rate of virulence genes hgbA,higbB and fimA was over 86.0％,the detection rate of toxA was 8.4％,while the virulence gene tbpA was not detected.There were also differences in the distribution vir-ulence genes in different capsular polysaccharide serotypes.Virulence factor pfhA was detected in type A and F but not in type D.The detection rate of adhesin gene tadD in serotype A(92.2％)was significantly higher than that of type D(9.3％),and,on the contrary,the detection rate of ad-hesin gene hsf-l in serotype D(90.7％)was significantly higher than that of type A(20.3％).Drug resistance analysis revealed that Pasteurella multocida showed high susceptibility to antimi-crobial drugs such as amoxicillin,ampicillin,cephalosporins,doxycycline,fosfenicol and ciprofloxa-cin,and showed strong resistance to antimicrobial drugs such as lincomycin,cotrimoxazole,genta-micin and amikacin,and there were 54 multi-drug resistant strains(78.3％).In summary,capsular polysaccharide serotypes were dominated by type A and D,lipopolysaccharide serotypes were dom-inated by L6,the distribution of some virulence genes varied greatly among different serotypes,and the proportion of multi-resistant strains was high,which provide reference for the prevention and control of this disease.

Objective To compare the efficacy and adherence of rivaroxaban versus low-molecular-weight heparin for prophylactic anticoagulation in cancer patients with venous thromboembolism(VTE).Methods A total of 120 intermediate-to-high VTE risk patients with malignant tumors admitted to Depart-ment of Hematology and Oncology,West China Longquan Hospital of Sichuan University between September 2021 and December 2022,were randomly assigned to the rivaroxaban group(n=60)and the low-molecular-weight heparin group(n=60)using the random number table.The rivaroxaban group received oral Rivaroxa-ban,while the low-molecular-weight heparin group received subcutaneous injections of low-molecular-weight heparin sodium for prophylactic anticoagulation.All patients were followed up for 180 days.The primary end-point was medication adherence.The secondary endpoints included the incidence of VTE,bleeding events,and changes in coagulation parameters.Results The rate of good medication adherence was significantly higher in the rivaroxaban group than in the low-molecular-weight heparin group(95.00％vs.88.33％,P＜0.05).However,there were no statistically significant differences in the incidence of VTE or overall bleeding events between the two groups(P＜0.05).Following treatment,parameters including fibrinogen,prothrombin time(PT),and D-dimer levels showed significant improvement from baseline in both groups.Compared to the low-molecular-weight heparin group,the Rivaroxaban group demonstrated significantly higher fibrinogen levels,shorter PT,and lower D-dimer levels(P＜0.05).Stepwise logistic regression analysis identified the post-treatment platelet(PLT)count as a significant factor influencing bleeding events during prophylactic antico-agulation(P＜0.05).Khorana score≥3(high risk)was identified as a risk factor for bleeding events(P＜0.05).The incidence of clinically relevant non-major bleeding(CRNMB)was higher in the rivaroxaban group[11.67％(7/60)]compared to the low-molecular-weight heparin group[8.33％(5/60)],although the differ-ence was not statistically significant(P＜0.05).Kaplan-Meier curve analysis revealed no significant difference in the cumulative incidence of bleeding-free events between the two groups(P＜0.05).Conclusion Oral ri-varoxaban and subcutaneous low-molecular-weight heparin demonstrate comparable efficacy and safety for VTE prevention in cancer patients,but rivaroxaban significantly improves patient's adherence.