Objective:To analyze the molecular characteristics of the virus in a local outbreak of dengue fever in Jiangsu province in 2023, and to provide a basis for the prevention and control of the outbreak.Methods:Serum samples were collected from suspected dengue patients in the acute phase of the outbreak for virus detection and serotyping by real-time fluorescence quantitative RT-PCR (RT-qPCR). Positive specimens were amplified with full-length genomic fragments and subjected to second-generation sequencing and related evolutionary analyses.Results:Four confirmed cases of dengue were found in Changzhou city, Jiangsu province, from October 18 to 21, 2023, with epidemiological association between the cases, which was recognized as a dengue outbreak. The serum RT-qPCR result of the four cases were all dengue type 1, and the whole genome sequences of three of the cases were obtained. The evolutionary tree of the E gene and the whole genome showed that the three sequences were located in the 3rd branch of the 1-I genotype, which is similar to the genotype 1-I. The genome-wide sequences of the E gene and the genome-wide evolution tree showed that the three sequences were located in the 3rd branch of the 1-I genotype, which is similar to the genome-wide genotype 1-Ⅰ. The E gene and the genome-wide evolutionary tree showed that all three sequences were located on branch 3 of genotype 1-Ⅰ, with high sequence similarity to the dengue virus epidemic strains in Guangdong and Yunnan provinces in 2023. Amino acid variant site analysis showed that there were 16 branch-specific amino acid site changes in the sequences of the three cases, among which the structural proteins, C protein and prM protein, had one variant site each, E protein had two, and the non-structural proteins had the largest number of NS5 variant sites (9).Conclusions:The local outbreak in Jiangsu was caused by dengue fever type 1 virus, with high nucleotide sequence similarity to strains from other regions of China, and amino acid site alterations.

Senecavirus A (SVA) is a major viral pathogen causing disease in pigs, and effective monitoring of SVA infection is critical for disease control. In this study, we aimed to develop a reliable ELISA method for rapidly detecting neutralizing antibodies against SVA. We used HEK293F cells to express an SVA-specific porcine Fab antibody and verified the biological activity of the Fab antibody by indirect ELISA, immunofluorescence assay, virus neutralization test, and Western blotting. The Fab antibody was biotinylated and used as a competitive antibody to establish a competitive ELISA (C-ELISA) for detecting neutralizing antibodies against SVA. We then evaluated the C-ELISA in terms of sensitivity, specificity, repeatability, and result agreement rate with the VNT. The results showed that we successfully prepared an SVA-specific porcine Fab antibody, which showed high affinity for SVA. We named this antibody 1M33Fab and designated it as Bio-1M33Fab after biotin labeling. The assay conditions were optimized as follows: the coating concentration of SVA particles being 1 μg/mL, the working concentration of Bio-1M33Fab being 0.5 μg/mL, the optimal serum dilution of 1:10, and the optimal dilution of enzyme-labeled avidin being 1:30 000. At a percent inhibition (PI) of 47%, the assay demonstrated the highest sensitivity (96.88%) and specificity (100%), with no cross-reactivity observed with the positive sera of major porcine viral diseases. The intra-assay coefficient of variation ranged from 1.12% to 7.34%, while the inter-assay coefficient of variation ranged from 1.10% to 8.97%, indicating good repeatability. In the detection of 224 clinical pig serum samples, C-ELISA and VNT showed a result agreement rate of 93.75%. In conclusion, we successfully develop a C-ELISA method for detecting neutralizing antibodies against SVA by using a porcine-derived Fab antibody, which lays a foundation for the development of detection kits.
Animals ; Swine ; Antibodies, Neutralizing/immunology* ; Enzyme-Linked Immunosorbent Assay/methods* ; Immunoglobulin Fab Fragments/immunology* ; Antibodies, Viral/immunology* ; Picornaviridae/immunology* ; Humans ; HEK293 Cells ; Swine Diseases/diagnosis* ; Picornaviridae Infections/diagnosis*

Objective:To investigate the G/P genotypes of group A rotavirus（RVA）in the 2023 sentinel surveillance in Jiangsu Province，and to conduct a molecular characterization analysis of the whole-genome sequences of four G9P［4］genotype RVA strains identified during surveillance.Methods:A total of 212 RVA-positive specimens collected from the surveillance system in 2023 were subjected to G/P genotyping using multiplex nested RT-PCR. Whole-genome sequencing was performed on six G9P［4］strains. The resulting complete genome sequences were preliminarily genotyped using BLAST，followed by comprehensive molecular characterization analyses utilizing BioEdit 7.0.5，MAFFT，MEGA 7.0，and iTOL software.Results:The overall RVA positivity rate was 6.22%. The predominant G/P combination in both outpatient and inpatient settings was G8P［8］. Among the six G9P［4］strains，four were successfully sequenced. All four exhibited the genotype constellation G9-P［4］-I2-R2-C2-M2-A2-N1-T2-E2-H2. While the NSP2 gene belonged to the N1 genotype，all other genes corresponded to the DS-1-like genogroup. Phylogenetically，the four Jiangsu G9P［4］strains clustered within Lineage V of the VP7 gene and formed a distinct minor subclade within the N1 branch of the NSP2 gene. Unique amino acid substitutions were identified at multiple VP7 neutralization antigenic epitope sites when compared to vaccine strains.Conclusions:The predominant circulating RVA strain in Jiangsu province during 2023 was G8P［8］. Concurrently，the relatively uncommon G9P［4］-N1 strain was detected. This strain exhibited significant amino acid differences at key epitopes compared to vaccine strains. Enhancing the proportion of whole-genome sequencing in RVA surveillance is warranted to obtain more detailed genetic information，thereby providing crucial data to support future vaccine development and optimization strategies.

Objective:To investigate the G/P genotypes of group A rotavirus（RVA）in the 2023 sentinel surveillance in Jiangsu Province，and to conduct a molecular characterization analysis of the whole-genome sequences of four G9P［4］genotype RVA strains identified during surveillance.Methods:A total of 212 RVA-positive specimens collected from the surveillance system in 2023 were subjected to G/P genotyping using multiplex nested RT-PCR. Whole-genome sequencing was performed on six G9P［4］strains. The resulting complete genome sequences were preliminarily genotyped using BLAST，followed by comprehensive molecular characterization analyses utilizing BioEdit 7.0.5，MAFFT，MEGA 7.0，and iTOL software.Results:The overall RVA positivity rate was 6.22%. The predominant G/P combination in both outpatient and inpatient settings was G8P［8］. Among the six G9P［4］strains，four were successfully sequenced. All four exhibited the genotype constellation G9-P［4］-I2-R2-C2-M2-A2-N1-T2-E2-H2. While the NSP2 gene belonged to the N1 genotype，all other genes corresponded to the DS-1-like genogroup. Phylogenetically，the four Jiangsu G9P［4］strains clustered within Lineage V of the VP7 gene and formed a distinct minor subclade within the N1 branch of the NSP2 gene. Unique amino acid substitutions were identified at multiple VP7 neutralization antigenic epitope sites when compared to vaccine strains.Conclusions:The predominant circulating RVA strain in Jiangsu province during 2023 was G8P［8］. Concurrently，the relatively uncommon G9P［4］-N1 strain was detected. This strain exhibited significant amino acid differences at key epitopes compared to vaccine strains. Enhancing the proportion of whole-genome sequencing in RVA surveillance is warranted to obtain more detailed genetic information，thereby providing crucial data to support future vaccine development and optimization strategies.

Objective:To analyze the molecular characteristics of the virus in a local outbreak of dengue fever in Jiangsu province in 2023, and to provide a basis for the prevention and control of the outbreak.Methods:Serum samples were collected from suspected dengue patients in the acute phase of the outbreak for virus detection and serotyping by real-time fluorescence quantitative RT-PCR (RT-qPCR). Positive specimens were amplified with full-length genomic fragments and subjected to second-generation sequencing and related evolutionary analyses.Results:Four confirmed cases of dengue were found in Changzhou city, Jiangsu province, from October 18 to 21, 2023, with epidemiological association between the cases, which was recognized as a dengue outbreak. The serum RT-qPCR result of the four cases were all dengue type 1, and the whole genome sequences of three of the cases were obtained. The evolutionary tree of the E gene and the whole genome showed that the three sequences were located in the 3rd branch of the 1-I genotype, which is similar to the genotype 1-I. The genome-wide sequences of the E gene and the genome-wide evolution tree showed that the three sequences were located in the 3rd branch of the 1-I genotype, which is similar to the genome-wide genotype 1-Ⅰ. The E gene and the genome-wide evolutionary tree showed that all three sequences were located on branch 3 of genotype 1-Ⅰ, with high sequence similarity to the dengue virus epidemic strains in Guangdong and Yunnan provinces in 2023. Amino acid variant site analysis showed that there were 16 branch-specific amino acid site changes in the sequences of the three cases, among which the structural proteins, C protein and prM protein, had one variant site each, E protein had two, and the non-structural proteins had the largest number of NS5 variant sites (9).Conclusions:The local outbreak in Jiangsu was caused by dengue fever type 1 virus, with high nucleotide sequence similarity to strains from other regions of China, and amino acid site alterations.

Objective:To compare the imaging quality and metabolic quantitative parameters of pulmonary nodules between Q. Flex whole information five-dimensional (5D) and conventional three-dimensional (3D) PET/CT imaging for clinical evaluation.Methods:Fifty-four patients (30 males, 24 females, age: 60(42, 75) years; 78 solid pulmonary nodules (maximum diameter≤3 cm) with abnormal uptake of 18F-FDG) from Tianjin Cancer Hospital Airport Hospital between June 2022 and August 2022 were enrolled in this retrospective study. All patients underwent 5D scanning and 3D, 5D reconstruction. Image quality scores, signal-to-noise ratio (SNR), SUV max, SUV mean and metabolic tumor volume (MTV) of pulmonary nodules of 5D group and 3D group were evaluated and compared with χ2 test and Wilcoxon signed rank test. Correlation of quantitative parameters between 2 groups were analyzed by using Spearman rank correlation analysis. Results:Thirty-five of 78(45%) pulmonary nodules with image quality score≥4 were found in 5D group, which were more than those in 3D group (22/78(28%); χ2=4.67, P=0.031). Meanwhile, SNR, SUV max, SUV mean, and MTV were significantly positively correlated between the 2 groups ( rs values: 0.86, 0.86, 0.85, and 0.95, all P<0.001). SNR, SUV max and SUV mean of pulmonary nodules in 5D group were significantly higher than those in 3D group, which were 37.46(18.42, 62.00) vs 32.72(16.97, 54.76) ( z=-4.07, P<0.001), 9.71(5.48, 13.82) vs 8.96(4.82, 12.63) ( z=-3.05, P<0.001) and 6.30(3.39, 8.94) vs 5.61(2.99, 7.63)( z=-4.07, P<0.001) respectively. MTV of pulmonary nodules in 5D group was significantly lower than that in 3D group, which was 1.72(0.66, 2.74) cm 3vs 1.98(1.06, 4.63) cm 3 ( z=-7.13, P<0.001). Quantitative parameters of lower lung field and nodules with maximum diameters of >10 mm and ≤20 mm based on 5D scanning changed most significantly compared with those based on 3D scanning ( z values: from -5.23 to -2.48, all P<0.05). Conclusion:Q. Flex 5D PET significantly improves the quantitative accuracy of SUV and MTV of pulmonary nodules, and the improvement of image quality is substantial without increasing the radiation dose, which has clinical practical value.

Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious disease caused by porcine reproductive and respiratory syndrome virus (PRRSV), which causes great economic losses. At the moment, no effective neutralizing antibody is available for scientific research and treatment. Therefore, developing a method for screening the neutralizing monoclonal antibodies is of great significance for the prevention and treatment of PRRSV and the screening of antigen sites. Monoclonal antibodies have been widely used in the treatment and diagnosis of many human and animal diseases. Therefore, screening effective neutralizing antibodies for different pathogens is an urgent task. Among the methods for monoclonal antibody screening, B cell immortalization is an effective method to obtain neutralizing monoclonal antibody. Specifically, in this study, the bcl-6 and bcl-xl genes were connected by f2a and then the yielded product was ligated to a vector for retrovirus packaging. The swine lymphocytes immunized with PRRSV were infected the yielded mature viruses and cultured in the complete medium containing CD40L and IL21 cytokines. Then, CD21 was used as the marker to screen B cells with the magnetic bead method. Finally, monoclonal B cells were obtained and the secretion of antibodies was tested. The results showed that the plasmid, either being transfected alone or with the packaged plasmids, could be expressed, and that the packaged retrovirus could infect the cells. Moreover, the infected lymphocytes secreted antibodies, so did the screened B cells. Therefore, the method for screening monoclonal antibody against PRRSV was successfully established.
Animals ; Antibodies, Monoclonal ; Antibodies, Neutralizing ; Antibodies, Viral ; Humans ; Porcine Reproductive and Respiratory Syndrome/prevention & control* ; Porcine respiratory and reproductive syndrome virus/genetics* ; Swine

Objective: To understand the knowledge, attitude and behavior of HIV/AIDS prevention and treatment of freshmen in Jiangsu Colleges, so as to provide evidence for carrying out HIV/AIDS prevention and treatment propaganda among young college students. Methods: A total of 2 538 freshmen in 8 colleges in Jiangsu province were surveyed by cluster sampling, and anonymous self-reported questionnaire survey was carried out. Valid questionnaires were collected and analyzed. Results: Among 2 538 students valid, the total awareness rate of the eight items of new HIV/AIDS basic knowledge which provided to the public by the State (referred to the new eight items) was 85.74%, the awareness rate of boys was higher than that of girls’(88.21%, 84.34%)(P<0.05), the rate of college students of science was higher that of those of arts(87.31%, 83.67%)(P<0.05). the general awareness rate of other knowledge was 72.14%, and the rate of boys was higher than that of girls(75.00%, 70.53%)(P<0.05). As for "whether eating with the AIDS-affected patients may be affected with AIDS/HIV", boys and students of science were more rational(58.3%, 55.1%; 50.4%, 50.9%)(P<0.05). 50.08% students approved of having sexual behavior before marriage, and the rate of boys was higher than that of girls(69.00%, 39.40%)(P<0.01). 71.24% of the students thought that condoms should be used consistently in sex behaviors, and the proportion of female students (80.76%) was much higher than that of male students(54.37%), and the rate of the students of science was higher than that of students of arts(73.36%, 69.63%)(P<0.05). 6.03% students had received consult and test of AIDS. 40.34% of the untested students were willing to receive the test but didn’t know where to go. 1.34% students were afraid of receiving the test because of fear. The most popular ways of HIV/AIDS publicity among students are micro films(76.32%), lectures(66.67%) and peer education(60.80%). Conclusion It is suggested to publicize HIV/AIDS knowledge among students according to different gender and subject characteristics and combining multimedia, with emphasis on strengthening the publicity of HIV/AIDS epidemiology,treatment and related information, and attaching importance to sexual health education among young students.

Antigenic purity is important for quality control of the foot-and-mouth (FMD) whole virus inactivated vaccine. The recommended method for evaluation the antigenic purity of FMD vaccine is to check the serum conversion to non-structural protein (NSP) 3AB antibody after 2 to 3 times inoculation of animals with inactivated vaccine. In this study, we developed a quantitative ELISA to detect the amount of residual 3AB in vaccine antigen, to provide a reference to evaluate the antigenic purity of FMD vaccine. Monoclonal antibody (Mab) of NSP 3A and HRP-conjugated Mab of NSP 3B were used to establish a sandwich ELISA to quantify the NSP 3AB in vaccine antigen of FMD. Purified NSP 3AB expressed in Escherichia coli was serially diluted and detected to draw the standard curve. The detectable limit was determined to be the lowest concentration of standard where the ratio of its OD value to OD blank well was not less than 2.0. Results: The OD value was linearly corelated with the concentration of 3AB protein within the range between 4.7 and 600 ng/mL. The correlation coefficient R² is greater than 0.99, and the lowest detectable limit is 4.7 ng/mL. The amount of 3AB protein in non-purified inactivated virus antigen was detected between 9.3 and 200 ng/mL depending on the 12 different virus strains, whereas the amount of 3AB in purified virus antigen was below the lowest detectable limit. The amount of 3AB in 9 batches of commercial FMD vaccine antigens was between 9.0 and 74 ng/mL, whereas it was below the detectable limit in other 24 batches of commercial vaccine antigens. Conclusion: the sandwich ELISA established in this study is specific and sensitive to detect the content of 3AB protein in vaccine antigen of FMD, which will be a useful method for evaluation of the antigenic purity and quality control of FMD inactivated vaccine.
Animals ; Antibodies, Viral ; Enzyme-Linked Immunosorbent Assay ; Foot-and-Mouth Disease/prevention & control* ; Foot-and-Mouth Disease Virus ; Viral Nonstructural Proteins/genetics* ; Viral Vaccines

Objective:To explore the effects of medical support program on local diagnosis,treatment and prognosis of acute myocardial infarction(AMI).Methods:Department of Cardiology,Zhongshan Hospital,Fudan University launched medical support program for Fuyuan People′s Hospital in Mar 2010.A total of 103 AMI patients admitted to Fuyuan People′s Hospital during Mar 2010 and Apr 2014 were enrolled.And 5 1 patients admitted during Mar 2010 and Nov 2012 were allocated to group A,while 52 patients admitted during Dec 2012 and Apr 2014 were allocated to group B.The treatment strategy,hospital stay, medication and prognosis were compared between the two groups.Results:Among the 103 AMI patients,male smoking pro-portion was significantly higher than female one(P <0.05).Only 21 patients with ST segment elevation myocardial infarction (STEMI)arrived hospital within 12 h.The thrombolytic therapy rate of patients with STEMI in group B was higher than that in group A(P <0.05).The usage rate of adenosine diphosphate(ADP)receptor antagonist(clopidegrel)during hospitalization in group B was higher than that in group A (P <0.05 ).Only 57 patients were followed up.And only 1/3 of these patients re-ceived consecutive coronary angiography and percutaneous coronary intervention(PCI).After discharge from hospital,the pre-scription rates of ADP receptor antagonist,β-receptor blockers and angiotension converting enzyme inhibitor (ACEI)all de-creased obviously and there was no significant difference between the two groups(P >0.05).There was no significant difference regarding the incidence rates of endpoint events between the two groups(P >0.05).Conclusions:Medical support program im-proves the rates of diagnosis and standardized treatment of AMI during hospitalization.However,the delay before admission has not been shortened yet.Furthermore,there was no standardized secondary prevention and treatment after discharge.Thus,apart from improving the ability of diagnosis and treatment during hospitalization,more attention should be paid to the health education for patients and the training for primary medical staff,and enhance the regional cooperation.