This study established an indirect ELISA method for antibody detection based on human rotavirus group A(RVA)VP6 protein,to provide technical support for RVA antibody detection.An ELISA method for detecting RVA antibodies was established through a checkerboard assay for optimization of the reaction conditions with VP6 protein of RVA as the diagnostic antigen.Serum samples from healthy children and patients infected with RVA were collected and detected with the ELISA method.The optimal work-ing conditions for ELISA involved coating the ELISA plate with VP6 protein at a concentration of 2 μg/mL and diluting the serum at a ratio of 1∶250.The critical value of negative and positive samples was 0.137.The ELISA method had good specificity,sensitivity,and repeatability,and showed a 95%consistency rate with the western blotting antibody detection method.We tested 370 serum samples collected from children,which showed an antibody positivity rate of 81.1%.We additionally tested the acute and recovery phase sera from 15 patients infected with RVA,and observed a significantly higher RVA antibody titer in the recovery phase serum than the acute infection phase serum.The ELISA antibody detection method showed good specificity,sensitivity,and reproducibility,and therefore can be used for RVA antibody detection and auxiliary diagnosis of RVA infection.

This study expressed the VP6 protein of human group A rotavirus in a prokaryotic expression system and prepared mouse polyclonal antibodies to this protein.The human rotavirus VP6 gene was amplified through RT-PCR from fecal samples infected with group A rotavirus and cloned into the pET-32a vector to construct the recombinant pET-32a-VP6 prokaryotic expression plas-mid.The recombinant plasmid was transformed into Escherichia coli BL21(DE3).VP6 protein was expressed through induction with isopropyl-β-D-thiopyranoside(IPTG),purified with nickel nitrilotriacetic acid(Ni-NTA)affinity chromatography,and identified through SDS-PAGE and western blotting.Polyclonal antibodies to the VP6 protein were obtained by immunization of BALB/c mice with VP6 protein.Antibody titers were determined through indirect ELISA.The recombinant expression plasmid pET-32a-VP6 was con-structed,and VP6 protein was expressed primarily in inclusion bodies.Polyclonal antibodies to VP6 protein with a titer of 1∶32 000 were obtained by immunization of mice with VP6 protein purified by affinity chromatography.The antibodies specifically reacted with VP6 protein.The VP6 protein of human group A rotavirus was expressed and purified,and mouse polyclonal antibodies to this protein were prepared,thus providing a foundation for the preparation of a diagnostic antigen for human group A rotavirus and the establishment of serological detection methods.

Objective To explore the biological mechanism of radiation resistance in esophageal squamous cell carcinoma(ESCC)and search for effective sensitization targets.Methods We retrieved 186 signaling pathways and related gene information from the MSigDB database.We also obtained RNA transcriptome data of ESCC patients using the Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO)databases.We collected clinical pathological characteristics and tissue samples of 97 ESCC patients in our hospital from 2013 to 2020.Gene set variation analysis(GSVA)was made to calculate KEGG signaling pathway score,radiotherapy resistance related signaling pathways were screened through random forest algorithm,key genes in the pathway were screened using DESeq2,and a radiotherapy efficacy prediction model was constructed based on support vector machine-recursive feature elimination(SVM-RFE).The results were validated through experiments such as Western blotting and clonogenic assay.Results Based on the KEGG signaling pathway and GSVA enrichment score,random forest analysis showed that in the TCGA and GSE45670 cohorts,the contribution of tryptophan metabolism pathway enrichment values to radiation resistance in ESCC was significantly better than that of the other pathways.DESeq2 analysis revealed that key molecules in the tryptophan metabolism pathway,namely,IDO1,ALDH1B1,AOC1,INMT,AFMID and ALDH7A1,were significantly differentially expressed in the resistant and sensitive groups of ESCC.Based on the SVM-RFE algorithm,the AUC was 0.77,which could accurately predict the radiotherapy efficacy of ESCC.Western blotting experiments showed that IDO1 was highly expressed in ESCC cells,and IDO1 inhibitor treatment significantly inhibited the survival ability and radiosensitivity of KYSE-410 cells.In the enrolled patients of our hospital,immunohistochemical studies showed that IDO1 was highly expressed in the radiotherapy resistant group of ESCC and was associated with poor radiotherapy prognosis in ESCC patients.In addition,further testing showed that the expression of IDO1 in patient samples from our hospital was positively correlated with its PD-L1 expression,but negatively correlated with the infiltration ratio of CD3/CD8 immune cells.Conclusion Tryptophan catabolism is associated with radiation resistance in ESCC,and the key enzyme IDO1 in tryptophan metabolism can be used as a therapeutic target for radiosensitization in ESCC.

OBJECTIVE To investigate the effects and underlying mechanisms of Yiqi Huoxue Decoction(YQHX)on mitochon-drial midzone division and peripheral fission in myocardial tissue after myocardial infarction(MI).METHODS A total of 48 male SPF-grade C57BL/6N mice were randomly divided into a sham-operated group(Sham,n=12)and a left anterior descending coronary ar-tery ligation MI model(n=36).After MI surgery,mice deemed to have successfully developed the model were randomly divided into a model group(MI,n=12),a YQHX group(n=12),and an empagliflozin group(EMPA,n=12)based on echocardiographic results.Four weeks after infarction,cardiac function and structural changes were comprehensively evaluated using echocardiography imaging,serum myocardial injury biomarkers,and hematoxylin-eosin(HE)staining.Transmission electron microscopy(TEM)was employed to observe mitochondrial ultrastructural,morphological,and quantitative changes at the peri-infarct zone.Myocardial mitochondria and cytoplas-mic fractions were isolated from myocardial tissue using a mitochondrial extraction kit,and the spatial expression changes of mitochon-drial fission-related proteins in both mitochondria and cytoplasm of the peri-infarct myocardium were analyzed by Western blot.These proteins included dynamin-related protein 1(Drp1),its phosphorylated form at serine 616(P-Drp1-Ser616),mitochondrial fission fac-tor(MFF),and mitochondrial fission protein 1(Fis1).RESULTS Compared with the MI group,mice in the YQHX group exhibited sig-nificantly increased left ventricular ejection fraction(LVEF)and left ventricular fractional shortening(LVFS)(P<0.000 1),as well as decreased left ventricular internal dimension-diastole(LVIDd)and left ventricular end-systolic diameter(LVIDs)(P<0.05,P<0.01),suggesting improved cardiac function.Additionally,serum levels of lactate dehydrogenase(LDH)and creatine kinase-MB(CK-MB)were significantly reduced in the YQHX group(P<0.05,P<0.001),indicating cardio-protective effects of YQHX against ischemic in-jury.HE staining showed that YQHX improved cellular morphology,suggesting structural improvement.TEM showed that YQHX sig-nificantly improved mitochondrial swelling and reduced mitochondrial fragmentation in the marginal zone of myocardial infarction,thereby preserving mitochondrial ultrastructure.Furthermore,Western blot showed that YQHX treatment significantly downregulated P-Drp1-Ser616 expression(P<0.05)in the cytoplasm.Interestingly,YQHX treatment significantly downregulated mitochondrial Fis1 expression(P<0.05),thereby inhibiting peripheral mitochondrial fission.Meanwhile,YQHX treatment significantly increased MFF ex-pression in mitochondria(P<0.01),which may promote mitochondrial midzone fission.CONCLUSION YQHX improves cardiac structure and function after MI,potentially by promoting myocardial mitochondrial midzone fission and inhibiting mitochondrial periph-eral fission in ischemic cardiomyocytes.

This study established an indirect ELISA method for antibody detection based on human rotavirus group A(RVA)VP6 protein,to provide technical support for RVA antibody detection.An ELISA method for detecting RVA antibodies was established through a checkerboard assay for optimization of the reaction conditions with VP6 protein of RVA as the diagnostic antigen.Serum samples from healthy children and patients infected with RVA were collected and detected with the ELISA method.The optimal work-ing conditions for ELISA involved coating the ELISA plate with VP6 protein at a concentration of 2 μg/mL and diluting the serum at a ratio of 1∶250.The critical value of negative and positive samples was 0.137.The ELISA method had good specificity,sensitivity,and repeatability,and showed a 95%consistency rate with the western blotting antibody detection method.We tested 370 serum samples collected from children,which showed an antibody positivity rate of 81.1%.We additionally tested the acute and recovery phase sera from 15 patients infected with RVA,and observed a significantly higher RVA antibody titer in the recovery phase serum than the acute infection phase serum.The ELISA antibody detection method showed good specificity,sensitivity,and reproducibility,and therefore can be used for RVA antibody detection and auxiliary diagnosis of RVA infection.

This study expressed the VP6 protein of human group A rotavirus in a prokaryotic expression system and prepared mouse polyclonal antibodies to this protein.The human rotavirus VP6 gene was amplified through RT-PCR from fecal samples infected with group A rotavirus and cloned into the pET-32a vector to construct the recombinant pET-32a-VP6 prokaryotic expression plas-mid.The recombinant plasmid was transformed into Escherichia coli BL21(DE3).VP6 protein was expressed through induction with isopropyl-β-D-thiopyranoside(IPTG),purified with nickel nitrilotriacetic acid(Ni-NTA)affinity chromatography,and identified through SDS-PAGE and western blotting.Polyclonal antibodies to the VP6 protein were obtained by immunization of BALB/c mice with VP6 protein.Antibody titers were determined through indirect ELISA.The recombinant expression plasmid pET-32a-VP6 was con-structed,and VP6 protein was expressed primarily in inclusion bodies.Polyclonal antibodies to VP6 protein with a titer of 1∶32 000 were obtained by immunization of mice with VP6 protein purified by affinity chromatography.The antibodies specifically reacted with VP6 protein.The VP6 protein of human group A rotavirus was expressed and purified,and mouse polyclonal antibodies to this protein were prepared,thus providing a foundation for the preparation of a diagnostic antigen for human group A rotavirus and the establishment of serological detection methods.

OBJECTIVE To investigate the effects and underlying mechanisms of Yiqi Huoxue Decoction(YQHX)on mitochon-drial midzone division and peripheral fission in myocardial tissue after myocardial infarction(MI).METHODS A total of 48 male SPF-grade C57BL/6N mice were randomly divided into a sham-operated group(Sham,n=12)and a left anterior descending coronary ar-tery ligation MI model(n=36).After MI surgery,mice deemed to have successfully developed the model were randomly divided into a model group(MI,n=12),a YQHX group(n=12),and an empagliflozin group(EMPA,n=12)based on echocardiographic results.Four weeks after infarction,cardiac function and structural changes were comprehensively evaluated using echocardiography imaging,serum myocardial injury biomarkers,and hematoxylin-eosin(HE)staining.Transmission electron microscopy(TEM)was employed to observe mitochondrial ultrastructural,morphological,and quantitative changes at the peri-infarct zone.Myocardial mitochondria and cytoplas-mic fractions were isolated from myocardial tissue using a mitochondrial extraction kit,and the spatial expression changes of mitochon-drial fission-related proteins in both mitochondria and cytoplasm of the peri-infarct myocardium were analyzed by Western blot.These proteins included dynamin-related protein 1(Drp1),its phosphorylated form at serine 616(P-Drp1-Ser616),mitochondrial fission fac-tor(MFF),and mitochondrial fission protein 1(Fis1).RESULTS Compared with the MI group,mice in the YQHX group exhibited sig-nificantly increased left ventricular ejection fraction(LVEF)and left ventricular fractional shortening(LVFS)(P<0.000 1),as well as decreased left ventricular internal dimension-diastole(LVIDd)and left ventricular end-systolic diameter(LVIDs)(P<0.05,P<0.01),suggesting improved cardiac function.Additionally,serum levels of lactate dehydrogenase(LDH)and creatine kinase-MB(CK-MB)were significantly reduced in the YQHX group(P<0.05,P<0.001),indicating cardio-protective effects of YQHX against ischemic in-jury.HE staining showed that YQHX improved cellular morphology,suggesting structural improvement.TEM showed that YQHX sig-nificantly improved mitochondrial swelling and reduced mitochondrial fragmentation in the marginal zone of myocardial infarction,thereby preserving mitochondrial ultrastructure.Furthermore,Western blot showed that YQHX treatment significantly downregulated P-Drp1-Ser616 expression(P<0.05)in the cytoplasm.Interestingly,YQHX treatment significantly downregulated mitochondrial Fis1 expression(P<0.05),thereby inhibiting peripheral mitochondrial fission.Meanwhile,YQHX treatment significantly increased MFF ex-pression in mitochondria(P<0.01),which may promote mitochondrial midzone fission.CONCLUSION YQHX improves cardiac structure and function after MI,potentially by promoting myocardial mitochondrial midzone fission and inhibiting mitochondrial periph-eral fission in ischemic cardiomyocytes.

Objective To explore the biological mechanism of radiation resistance in esophageal squamous cell carcinoma(ESCC)and search for effective sensitization targets.Methods We retrieved 186 signaling pathways and related gene information from the MSigDB database.We also obtained RNA transcriptome data of ESCC patients using the Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO)databases.We collected clinical pathological characteristics and tissue samples of 97 ESCC patients in our hospital from 2013 to 2020.Gene set variation analysis(GSVA)was made to calculate KEGG signaling pathway score,radiotherapy resistance related signaling pathways were screened through random forest algorithm,key genes in the pathway were screened using DESeq2,and a radiotherapy efficacy prediction model was constructed based on support vector machine-recursive feature elimination(SVM-RFE).The results were validated through experiments such as Western blotting and clonogenic assay.Results Based on the KEGG signaling pathway and GSVA enrichment score,random forest analysis showed that in the TCGA and GSE45670 cohorts,the contribution of tryptophan metabolism pathway enrichment values to radiation resistance in ESCC was significantly better than that of the other pathways.DESeq2 analysis revealed that key molecules in the tryptophan metabolism pathway,namely,IDO1,ALDH1B1,AOC1,INMT,AFMID and ALDH7A1,were significantly differentially expressed in the resistant and sensitive groups of ESCC.Based on the SVM-RFE algorithm,the AUC was 0.77,which could accurately predict the radiotherapy efficacy of ESCC.Western blotting experiments showed that IDO1 was highly expressed in ESCC cells,and IDO1 inhibitor treatment significantly inhibited the survival ability and radiosensitivity of KYSE-410 cells.In the enrolled patients of our hospital,immunohistochemical studies showed that IDO1 was highly expressed in the radiotherapy resistant group of ESCC and was associated with poor radiotherapy prognosis in ESCC patients.In addition,further testing showed that the expression of IDO1 in patient samples from our hospital was positively correlated with its PD-L1 expression,but negatively correlated with the infiltration ratio of CD3/CD8 immune cells.Conclusion Tryptophan catabolism is associated with radiation resistance in ESCC,and the key enzyme IDO1 in tryptophan metabolism can be used as a therapeutic target for radiosensitization in ESCC.

Objective:To explore the clinical efficacy of retrograde tibial intramedullary nail (RTN) combined with less invasive stabilization system (LISS) in the treatment of distal femoral fractures.Methods:A retrospective analysis was conducted on the data of 11 patients with distal femoral fractures who underwent RTN combined with LISS locking plate treatment at the 909th Hospital from June 2021 to December 2022. There were 5 males and 6 females, with an average age of 56.5±17.5 years. The fracture types were AO/OTA 33A2 in 2 cases, A3 in 2 cases, C1 in 2 cases, and C2 in 2 cases. There were 3 cases of periprosthetic femoral fractures after total knee arthroplasty (TKA), all classified as Rorabeck type Ⅱ. They were treated with retrograde intramedullary nailing of the tibia combined with a minimally invasive lateral internal fixation system. The operation time, intraoperative blood loss, fracture healing time, full weight-bearing time, femorotibial angle, range of motion (ROM) of the knee joint, Hospital for Special Surgery (HSS) score, visual analogue scale (VAS) for pain, and complications were recorded.Results:The operation was successfully completed in all 11 cases. The operation time was 98.3±9.0 min (range 83-115 min), and the intraoperative blood loss was 167.8±24.3 ml (range 120-210 ml). All 11 cases were followed up for 11.0±1.9 months (range 9-15 months). The healing time of 11 cases was 5.3±0.8 months (range 4-6 months) after operation. The time of complete weight-bearing activity after operation was 55.7±6.5 d (range 46-67 d). At the last follow-up, the femoral-tibial angle of 11 cases was 171.2°±1.8° (range 169°-174°), the ROM of knee joint was 129.5°±4.7° (range 120°-135°), and the HSS score was 86.8±6.9 points (range 69-95 points). There were no major complications except for one case of superficial infection of surgical incision after operation.Conclusion:RTN combined with lateral LISS locking plate showed good clinical effect with the advantages of less trauma, reliable fixation, rapid recovery, less postoperative complications.

Objective:To evaluate the clinical efficacy of a novel surgical approach of debridement, antibiotics, and implant retention (DAIR) with flap transfer, for treating chronic implant infections in bone tumor patients.Methods:A retrospective review was conducted on nine consecutive patients [6 males, 3 females; median age 35(27, 51) years, range 9-71] who underwent a modified procedure of DAIR plus flap transfer between November 2022 and January 2024. The cohort included six cases of chronic periprosthetic joint infection and three cases of chronic plate and screw infection. Tumor diagnoses included seven primary malignant tumors (osteosarcoma=5, undifferentiated pleomorphic sarcoma of bone=1, synovial sarcoma=1) and two bone metastasis of renal cell carcinoma. The procedure involved wide, radical debridement, meticulous removal of biofilm from implants and surrounding soft tissue, followed by the transfer of a well vascularized musculocutaneous flap to fully envelope the contaminated interface. Pre-operative clinicopathological data, surgical details, postoperative complications and infection recurrence were analyzed.Results:The median interval between initial implantation and debridement was 10.0(3.3, 14.8) months. Median follow-up after debridement was 15.9(15.4, 18.2) months. All nine surgeries were completed as planned: six musculocutaneous flaps, two fasciocutaneous flaps and one muscle-only flap. Implants were preserved in six patients; two required subsequent removal for recurrent infection, and one patient later underwent amputation for tumor recurrence. Infection-free implant survival at 3, 6 and 12 months was 88.9%, 87.5% and 87.5%, respectively. Major complications included one donor-site hematoma, one donor-site sensory deficit and one wound healing delay. All the complications were well management. Both reinfections occurred in proximal tibial prostheses, likely due to limited flap coverage options and local anatomical constraints.Conclusion:Although reinfections happened in two cases DAIR with flap transfer provides promising short-term infection control in patients with chronic implant-associated infections following bone tumor surgery.