To prepare monoclonal antibody to the N protein of porcine reproductive and respiratory syndrome virus(PRRSV),BALB/c mice were immunized with the purified N protein of the PRRSV-2 strain expressed by prokaryotic expression system.Mouse splenocytes were fused with myeloma cells using hybridoma technique,hybridoma cells were identified by indirect ELISA method and indirect immunofluorescence assay(IFA),and positive hybridoma cells were screened for subclones using the limited dilution method.The results showed that a monoclonal antibody cell line 4A7 was successfully obtained,and the results of Western blot and IFA indicated that the monoclonal antibody could accurately recognize the N proteins of type 1 and type 2 PRRSV.Mean-while,the N protein gene was truncated and expressed by prokaryotic expression system,and the amino acid sequence of the B-cell antigenic epitope recognized by 4A7 was screened as 51EKPHF55 using Western blot.Comparison of epitope amino acids in the N protein gene sequences of different strains revealed that the antigenic epitope 51EKPHF55 recognized by the monoclonal antibody 4A7 has no amino acid difference in the sequences of three subtypes among the PRRSV-1 strains and nine lineages among the PRRSV-2 strains,indicating a high degree of conservation.The results of the study provide a foundation the development of PRRSV diagnostic kits and novel vaccines.

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 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.

To prepare monoclonal antibody to the N protein of porcine reproductive and respiratory syndrome virus(PRRSV),BALB/c mice were immunized with the purified N protein of the PRRSV-2 strain expressed by prokaryotic expression system.Mouse splenocytes were fused with myeloma cells using hybridoma technique,hybridoma cells were identified by indirect ELISA method and indirect immunofluorescence assay(IFA),and positive hybridoma cells were screened for subclones using the limited dilution method.The results showed that a monoclonal antibody cell line 4A7 was successfully obtained,and the results of Western blot and IFA indicated that the monoclonal antibody could accurately recognize the N proteins of type 1 and type 2 PRRSV.Mean-while,the N protein gene was truncated and expressed by prokaryotic expression system,and the amino acid sequence of the B-cell antigenic epitope recognized by 4A7 was screened as 51EKPHF55 using Western blot.Comparison of epitope amino acids in the N protein gene sequences of different strains revealed that the antigenic epitope 51EKPHF55 recognized by the monoclonal antibody 4A7 has no amino acid difference in the sequences of three subtypes among the PRRSV-1 strains and nine lineages among the PRRSV-2 strains,indicating a high degree of conservation.The results of the study provide a foundation the development of PRRSV diagnostic kits and novel vaccines.

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.

Purpose To investigate the risk factors of severe hypocalcemia after ultrasound-guided thermal ablation for secondary hyperparathyroidism.Materials and Methods A retrospective case-control study was used to study 91 patients with uremia complicated with secondary hyperparathyroidism in the First People's Hospital of Yulin from May 2019 to May 2023.All patients underwent ultrasound-guided thermal ablation and were divided into severe hypocalcemia group(SH)and non-SH group according to postoperative blood calcium levels.The difference of clinical data between the two groups was compared,and the independent risk factors of SH were investigated by multivariate Logistic regression analysis.Results A total of 317 glands were ablated in 49 cases of microwave ablation and 42 cases of radiofrequency ablation.SH occurred in 57 cases(62.64%)after ablation.The comparison of clinical data between the two groups showed that there were significant differences in the preoperative intact parathyroid hormone(iPTH),decline rate of iPTH 1 d,preoperative serum alkaline phosphatase,the proportion of parathyroid glands≥4 and the total gland volume between the two groups(all P<0.05).Receiver operating characteristic curve analysis was used to obtain the best cut-off point of iPTH 1 d decline rate,the result was 74.59%,the area under the curve was 0.866(95%CI 0.787-0.945)(P<0.05),the sensitivity was 84.2%,and the specificity was 78.1%.Multivariate Logistic regression analysis showed that preoperative alkaline phosphatase(OR=1.015,95%CI 1.005-1.025,P=0.030)and decline rate of iPTH 1 d≥74.59%(OR=30.423,95%CI 5.938-155.858,P<0.001)and parathyroid glands≥4(OR=4.355,95%CI 1.027-18.469,P=0.046)were independent risk factors for postoperative SH(all P<0.05).Conclusion Preoperative alkaline phosphatase and decline rate of iPTH 1 d≥74.59%and the number of parathyroid glands≥4 are independent risk factors for SH after thermal ablation.

Objective:To investigate the safety and efficacy of total pelvic exenteration (TPE) for treating late complications of radiation-induced pelvic injury.Methods:This was a descriptive case series study. The inclusion criteria were as follows: (1) confirmed radiation-induced pelvic injury after radiotherapy for pelvic malignancies; (2) late complications of radiation-induced pelvic injury, such as bleeding, perforation, fistula, and obstruction, involving multiple pelvic organs; (3) TPE recommended by a multidisciplinary team; (4) patient in good preoperative condition and considered fit enough to tolerate TPE; and (5) patient extremely willing to undergo the procedure and accept the associated risks. The exclusion criteria were as follows: (1) preoperative or intraoperative diagnosis of tumor recurrence or metastasis; (2) had only undergone diversion or bypass surgery after laparoscopic exploration; and (3) incomplete medical records. Clinical and follow-up data of patients who had undergone TPE for late complications of radiation-induced pelvic injury between March 2020 and September 2022 at the Sixth Affiliated Hospital of Sun Yat-sen University were analyzed. Perioperative recovery, postoperative complications, perioperative deaths, and quality of life 1 year postoperatively were recorded.Results:The study cohort comprised 14 women, nine of whom had recto-vagino-vesical fistulas, two vesicovaginal fistulas, one ileo-vesical fistula and rectal necrosis, one ileo-vesical and rectovaginal fistulas, and one rectal ulcer and bilateral ureteral stenosis. The mean duration of surgery was 592.1±167.6 minutes and the median blood loss 550 (100–6000) mL. Ten patients underwent intestinal reconstruction, and four the Hartmann procedure. Ten patients underwent urinary reconstruction using Bricker's procedure and 7 underwent pelvic floor reconstruction. The mean postoperative hospital stay was 23.6±14.9 days. Seven patients (7/14) had serious postoperative complications (Clavien-Dindo IIIa to IVb), including surgical site infections in eight, abdominopelvic abscesses in five, pulmonary infections in five, intestinal obstruction in four, and urinary leakage in two. Empty pelvis syndrome (EPS) was diagnosed in five patients, none of whom had undergone pelvic floor reconstruction. Five of the seven patients who had not undergone pelvic floor reconstruction developed EPS, compared with none of those who had undergone pelvic floor reconstruction. One patient with EPS underwent reoperation because of a pelvic abscess, pelvic hemorrhage, and intestinal obstruction. There were no perioperative deaths. During 18.9±10.1 months of follow-up, three patients died, two of renal failure, which was a preoperative comorbidity, and one of COVID-19. The remaining patients had gradual and significant relief of symptoms during follow-up. QLQ-C30 assessment of postoperative quality of life showed gradual improvement in all functional domains and general health at 1, 3, and 6 months postoperatively (all P<0.05). Conclusions:TPE is a feasible procedure for treating late complications of radiation-induced pelvic injury combined with complex pelvic fistulas. TPE is effective in alleviating symptoms and improving quality of life. However, the indications for this procedure should be strictly controlled and the surgery carried out only by experienced surgeons.

Objective To observe the risk factors of recurrence after ultrasound-guided thermal ablation for treating uremia secondary hyperparathyroidism(SHPT).Methods Totally 59 patients with uremia SHPT who underwent ultrasound-guided thermal ablation were enrolled,including 23 cases with(relapse group)and 36 without SHPT recurrence(non relapsed group).Clinical data were compared between groups,univariate and multivariate logistic regression analysis were performed to screen independent risk factors of SHPT recurrence.Results There were significant differences of serum free thyroxine(FT4),urea,intact parathyroid hormone(iPTH)1 day after ablation,1 day decrease rate of iPTH,the maximum diameter of the largest nodule,ablation time,total ablation energy,energy to volume ratio and the proportion of 1 day decrease rate of iPTH≤90%between groups(all P＜0.05).Higher urea,lower energy to volume ratio and 1 day decrease rate of iPTH≤90%were all independent risk factors of SHPT recurrence(all P＜0.05).Conclusion Higher urea,lower energy to volume ratio and 1 day decrease rate of iPTH≤90%were independent risk factors of recurrence after ultrasound-guided thermal ablation for treating uremia SHPT.

Objective:To investigate the safety and efficacy of total pelvic exenteration (TPE) for treating late complications of radiation-induced pelvic injury.Methods:This was a descriptive case series study. The inclusion criteria were as follows: (1) confirmed radiation-induced pelvic injury after radiotherapy for pelvic malignancies; (2) late complications of radiation-induced pelvic injury, such as bleeding, perforation, fistula, and obstruction, involving multiple pelvic organs; (3) TPE recommended by a multidisciplinary team; (4) patient in good preoperative condition and considered fit enough to tolerate TPE; and (5) patient extremely willing to undergo the procedure and accept the associated risks. The exclusion criteria were as follows: (1) preoperative or intraoperative diagnosis of tumor recurrence or metastasis; (2) had only undergone diversion or bypass surgery after laparoscopic exploration; and (3) incomplete medical records. Clinical and follow-up data of patients who had undergone TPE for late complications of radiation-induced pelvic injury between March 2020 and September 2022 at the Sixth Affiliated Hospital of Sun Yat-sen University were analyzed. Perioperative recovery, postoperative complications, perioperative deaths, and quality of life 1 year postoperatively were recorded.Results:The study cohort comprised 14 women, nine of whom had recto-vagino-vesical fistulas, two vesicovaginal fistulas, one ileo-vesical fistula and rectal necrosis, one ileo-vesical and rectovaginal fistulas, and one rectal ulcer and bilateral ureteral stenosis. The mean duration of surgery was 592.1±167.6 minutes and the median blood loss 550 (100–6000) mL. Ten patients underwent intestinal reconstruction, and four the Hartmann procedure. Ten patients underwent urinary reconstruction using Bricker's procedure and 7 underwent pelvic floor reconstruction. The mean postoperative hospital stay was 23.6±14.9 days. Seven patients (7/14) had serious postoperative complications (Clavien-Dindo IIIa to IVb), including surgical site infections in eight, abdominopelvic abscesses in five, pulmonary infections in five, intestinal obstruction in four, and urinary leakage in two. Empty pelvis syndrome (EPS) was diagnosed in five patients, none of whom had undergone pelvic floor reconstruction. Five of the seven patients who had not undergone pelvic floor reconstruction developed EPS, compared with none of those who had undergone pelvic floor reconstruction. One patient with EPS underwent reoperation because of a pelvic abscess, pelvic hemorrhage, and intestinal obstruction. There were no perioperative deaths. During 18.9±10.1 months of follow-up, three patients died, two of renal failure, which was a preoperative comorbidity, and one of COVID-19. The remaining patients had gradual and significant relief of symptoms during follow-up. QLQ-C30 assessment of postoperative quality of life showed gradual improvement in all functional domains and general health at 1, 3, and 6 months postoperatively (all P<0.05). Conclusions:TPE is a feasible procedure for treating late complications of radiation-induced pelvic injury combined with complex pelvic fistulas. TPE is effective in alleviating symptoms and improving quality of life. However, the indications for this procedure should be strictly controlled and the surgery carried out only by experienced surgeons.