Objective Through in vitro experiments,biomechanical data of the transtibial pullout suture(TPS),tendon reconstruction(TR),and tendon reconstruction with suture augmentation(TRS)were collected,so as to evaluate the biomechanical effectiveness of tendon reconstruction for repairing medial meniscus posterior root tear(MMPRT).Methods Eighteen porcine knee joint models were divided into TPS,TR,and TRS groups.Sutures were used to fix the meniscal root in TPS group.Tendons were passed through an incision at the meniscal root in TR group.Tendons were passed through an incision at the meniscal root and secured at tendon-meniscus contact area with additional sutures in TRS group.The sutures and tendons were pulled out through tibial tunnels and fixed at the anteromedial tibia.All groups underwent failure load tests,and ultimate failure load,displacement at failure load,load at clinical failure,stiffness,and failure modes of the samples were recorded.Results The maximum failure load in TPS group was significantly higher than that in TR group(P＜0.05),but there was no significant difference between TPS group and TRS group(P＞0.05).The maximum failure load in TRS group was significantly higher than that in TR group(P＜0.05).The displacement under failure load in TR group and TRS group was significantly lower than that in TPS group(P＜0.05),but there was no significant difference between TR group and TRS group(P＞0.05).There were no significant differences in the load under clinical failure among the 3 groups(P＞0.05).The stiffness of TRS group was significantly greater than that of TPS group(P＜0.05),but no significant difference was observed between TR group and TPS group,as well as between TR group and TRS group(P＞0.05).All failures were caused by suture or tendon cutting through the meniscus.Conclusions The tendon reconstruction techniques is superior to the TPS in terms of failure displacement and stiffness,while the TRS further enhances the stability of the repair.

Objective Through in vitro experiments,biomechanical data of the transtibial pullout suture(TPS),tendon reconstruction(TR),and tendon reconstruction with suture augmentation(TRS)were collected,so as to evaluate the biomechanical effectiveness of tendon reconstruction for repairing medial meniscus posterior root tear(MMPRT).Methods Eighteen porcine knee joint models were divided into TPS,TR,and TRS groups.Sutures were used to fix the meniscal root in TPS group.Tendons were passed through an incision at the meniscal root in TR group.Tendons were passed through an incision at the meniscal root and secured at tendon-meniscus contact area with additional sutures in TRS group.The sutures and tendons were pulled out through tibial tunnels and fixed at the anteromedial tibia.All groups underwent failure load tests,and ultimate failure load,displacement at failure load,load at clinical failure,stiffness,and failure modes of the samples were recorded.Results The maximum failure load in TPS group was significantly higher than that in TR group(P＜0.05),but there was no significant difference between TPS group and TRS group(P＞0.05).The maximum failure load in TRS group was significantly higher than that in TR group(P＜0.05).The displacement under failure load in TR group and TRS group was significantly lower than that in TPS group(P＜0.05),but there was no significant difference between TR group and TRS group(P＞0.05).There were no significant differences in the load under clinical failure among the 3 groups(P＞0.05).The stiffness of TRS group was significantly greater than that of TPS group(P＜0.05),but no significant difference was observed between TR group and TPS group,as well as between TR group and TRS group(P＞0.05).All failures were caused by suture or tendon cutting through the meniscus.Conclusions The tendon reconstruction techniques is superior to the TPS in terms of failure displacement and stiffness,while the TRS further enhances the stability of the repair.

Objective:To provide novel genetic biomarkers for the diagnosis and treatment of sepsis,bioinformatics analysis was used to screen differentially expressed genes and identify Hub genes in sepsis.Methods:Gene Expression Omnibus(GEO)database was used to retrieve gene expression datasets of sepsis and screen for differentially expressed genes(DEGs).Protein-protein interaction(PPI)network analysis,Gene Ontology(GO)analysis,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis were used to clarify the molecular mechanism of DEGs,and Hub genes were screened.Results:A total of 361 DEGs were identified,including 163 up-regulated genes and 198 down-regulated genes.Enrichment analysis revealed that these DEGs were primarily involved in antigen processing and presentation,T cell biology,cell adhesion molecules,and T cell receptor signaling pathways.CD4,TP53,PTPRC,LCK,ITGAM,ZAP70,CD247,CD2,CD3E,and HSP90AB1 were determined as optimal diagnostic biomarkers for sepsis.Conclusions:This study elucidated 10 Hub genes(CD4,TP53,PTPRC,LCK,ITGAM,ZAP70,CD247,CD2,CD3E,and HSP90AB1)as potential biomarkers for the diagnosis and treatment of sepsis.However,since the the generalizability of these Hub genes in patients with sepsis remains unvalidated,further experimental verification is still needed in the future.

Objective:To provide novel genetic biomarkers for the diagnosis and treatment of sepsis,bioinformatics analysis was used to screen differentially expressed genes and identify Hub genes in sepsis.Methods:Gene Expression Omnibus(GEO)database was used to retrieve gene expression datasets of sepsis and screen for differentially expressed genes(DEGs).Protein-protein interaction(PPI)network analysis,Gene Ontology(GO)analysis,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis were used to clarify the molecular mechanism of DEGs,and Hub genes were screened.Results:A total of 361 DEGs were identified,including 163 up-regulated genes and 198 down-regulated genes.Enrichment analysis revealed that these DEGs were primarily involved in antigen processing and presentation,T cell biology,cell adhesion molecules,and T cell receptor signaling pathways.CD4,TP53,PTPRC,LCK,ITGAM,ZAP70,CD247,CD2,CD3E,and HSP90AB1 were determined as optimal diagnostic biomarkers for sepsis.Conclusions:This study elucidated 10 Hub genes(CD4,TP53,PTPRC,LCK,ITGAM,ZAP70,CD247,CD2,CD3E,and HSP90AB1)as potential biomarkers for the diagnosis and treatment of sepsis.However,since the the generalizability of these Hub genes in patients with sepsis remains unvalidated,further experimental verification is still needed in the future.

Objective To compare the impact of different primary tumor sites on the survival of patients with metastatic urothelial carcinoma(mUC)before and after the approval of immune checkpoints inhibitors(ICIs)based on data from Surveillance,Epidemiology,and End Results(SEER).Methods The mUC cases during 2013 and 2017 in the SEER database were enrolled.Cohorts were defined by primary tumor sites(renal pelvis,ureter,bladder)and then stratified by ICIs availability into non-ICIs era(2013)and ICIs era(2017).The survival differences in each cohort between the two eras were compared,and stratified analysis was performed.The 2-year overall survival(OS)was assessed using Kaplan-Meier analysis and multivariable Cox proportional hazards analysis.Results A total of 1750 mUC cases were enrolled,with 785 cases in the non-ICIs era and 965 in the ICIs era.No significant differences existed across different anatomical sites in the non-ICIs era,whether in the whole urinary system or inside bladder.The 2-year survival rates were 23.5％for ureteral cancer,18.0％for renal pelvic cancer,and 15.9％for bladder cancer.Significant prognostic disparities emerged among patients based on primary tumor sites in ICIs era(P＜0.05).The 2-year survival rates were 37.7％for ureteral cancer,25.5％for renal pelvic cancer,and 25.7％for bladder cancer.Further analysis revealed that the OS of the lesions originating from the bladder dome was significantly longer than that of the other bladder subgroups(P＜0.05),while the OS of the lesions in bladder bottom was the shortest.The 2-year survival rates were 52.0％for the bladder dome,13.0％for the bladder body,and 10.7％for the bladder bottom.Conclusion Our study indicates that in the non-ICIs era,there was no significant difference in the prognosis among mUC patients with lesions from different primary sites.In the ICIs era,the OS of ureteral cancer was significantly longer than that of bladder cancer and renal pelvis cancer.As for patients with metastatic bladder cancer,those with tumor located at the top of the bladder had a significantly better prognosis than those with tumors at other sites.

Collagen is a matrix protein essential for maintaining the function of various tissues in ani-mals.There are many types of collagen in vertebrates,and the function of each type of collagen in the body is closely related to its sequence and structure.In addition to the common Gly-X-Y amino acid se-quence,there is also a special structure Gly-Gly-Y in the natural collagen.In order to explore its effect on collagen,this study constructed mutants containing Gly-Gly-Y at the levels of collagen polypeptides,long-chain collagen,and collagen polymers.The thermal stability of the mutant before and after mutation was characterized by circular dichroism scanning.At the same time,molecular dynamics simulation was used to calculate the hydrogen bonding probability and bending degree of collagen polypeptides,explai-ning the molecular mechanism of changes in collagen stability and flexibility.The results showed that the mutant containing the Gly-Gly structure would decrease the Tm value of the sample,but this effect would gradually weaken as the collagen triple helix region lengthened and the degree of protein self-assembly in-creased,and the reduced Tm values are 5 ℃,3 ℃,and 1 ℃,respectively.At the same time,the sim-ulation results show that the curvature of the polypeptide containing the Gly-Gly structure also increases to some extent,indicating that the structure near the mutation site has greater flexibility.This provides a new idea for the design of rubber materials with certain flexibility.

Objective To compare the impact of different primary tumor sites on the survival of patients with metastatic urothelial carcinoma(mUC)before and after the approval of immune checkpoints inhibitors(ICIs)based on data from Surveillance,Epidemiology,and End Results(SEER).Methods The mUC cases during 2013 and 2017 in the SEER database were enrolled.Cohorts were defined by primary tumor sites(renal pelvis,ureter,bladder)and then stratified by ICIs availability into non-ICIs era(2013)and ICIs era(2017).The survival differences in each cohort between the two eras were compared,and stratified analysis was performed.The 2-year overall survival(OS)was assessed using Kaplan-Meier analysis and multivariable Cox proportional hazards analysis.Results A total of 1750 mUC cases were enrolled,with 785 cases in the non-ICIs era and 965 in the ICIs era.No significant differences existed across different anatomical sites in the non-ICIs era,whether in the whole urinary system or inside bladder.The 2-year survival rates were 23.5％for ureteral cancer,18.0％for renal pelvic cancer,and 15.9％for bladder cancer.Significant prognostic disparities emerged among patients based on primary tumor sites in ICIs era(P＜0.05).The 2-year survival rates were 37.7％for ureteral cancer,25.5％for renal pelvic cancer,and 25.7％for bladder cancer.Further analysis revealed that the OS of the lesions originating from the bladder dome was significantly longer than that of the other bladder subgroups(P＜0.05),while the OS of the lesions in bladder bottom was the shortest.The 2-year survival rates were 52.0％for the bladder dome,13.0％for the bladder body,and 10.7％for the bladder bottom.Conclusion Our study indicates that in the non-ICIs era,there was no significant difference in the prognosis among mUC patients with lesions from different primary sites.In the ICIs era,the OS of ureteral cancer was significantly longer than that of bladder cancer and renal pelvis cancer.As for patients with metastatic bladder cancer,those with tumor located at the top of the bladder had a significantly better prognosis than those with tumors at other sites.

To investigate the molecular mechanisms underlying the mechanosensitive ion channel PI-EZO2 in osteoarthritis(OA),we developed a lentiviral vector for endogenous PIEZO2 overexpression and established a stable PIEZO2-high-expressing immortalized human primary chondrocyte line.By map-ping the open reading frame of the PIEZO2 locus and designing sequence-specific sgRNA,we employed the CRISPR/Cas9 synergistic activation mediator(SAM)system to precisely integrate transcriptional ac-tivation elements into the PIEZO2 promoter region.Lentiviral-mediated targeted genomic integration en-sured endogenous PIEZO2 overexpression,confirmed by mCherry fluorescence tracing coupled with flow cytometric sorting,which revealed membrane-specific localization of PIEZO2 protein(localization effi-ciency:78.49％).Quantitative PCR demonstrated a 17-fold upregulation of PIEZO2 mRNA,while Western blotting validated enhanced membrane-localized protein expression.Strikingly,PIEZO2-overex-pressing chondrocytes exhibited hallmark OA metabolic phenotypes compared to wild-type controls:typeⅡ collagen mRNA expression decreased to 50％of baseline levels,whereas matrix metalloproteinase 13(MMP13)mRNA surged by 20-fold.These alterations recapitulated the pathological matrix metabolic phenotype observed in biomechanical OA models induced by cyclic mechanical stress(10％strain,0.5 Hz,8 h/day for 2 consecutive days).Collectively,we successfully generated a human chondrocyte model with stable PIEZO2 overexpression,which faithfully mirrors mechanotransduction-driven OA progression.This engineered cellular system provides a robust platform for dissecting PIEZO2-mediated mechanosig-naling networks and advancing targeted therapeutic discovery.

Collagen is a matrix protein essential for maintaining the function of various tissues in ani-mals.There are many types of collagen in vertebrates,and the function of each type of collagen in the body is closely related to its sequence and structure.In addition to the common Gly-X-Y amino acid se-quence,there is also a special structure Gly-Gly-Y in the natural collagen.In order to explore its effect on collagen,this study constructed mutants containing Gly-Gly-Y at the levels of collagen polypeptides,long-chain collagen,and collagen polymers.The thermal stability of the mutant before and after mutation was characterized by circular dichroism scanning.At the same time,molecular dynamics simulation was used to calculate the hydrogen bonding probability and bending degree of collagen polypeptides,explai-ning the molecular mechanism of changes in collagen stability and flexibility.The results showed that the mutant containing the Gly-Gly structure would decrease the Tm value of the sample,but this effect would gradually weaken as the collagen triple helix region lengthened and the degree of protein self-assembly in-creased,and the reduced Tm values are 5 ℃,3 ℃,and 1 ℃,respectively.At the same time,the sim-ulation results show that the curvature of the polypeptide containing the Gly-Gly structure also increases to some extent,indicating that the structure near the mutation site has greater flexibility.This provides a new idea for the design of rubber materials with certain flexibility.

To investigate the molecular mechanisms underlying the mechanosensitive ion channel PI-EZO2 in osteoarthritis(OA),we developed a lentiviral vector for endogenous PIEZO2 overexpression and established a stable PIEZO2-high-expressing immortalized human primary chondrocyte line.By map-ping the open reading frame of the PIEZO2 locus and designing sequence-specific sgRNA,we employed the CRISPR/Cas9 synergistic activation mediator(SAM)system to precisely integrate transcriptional ac-tivation elements into the PIEZO2 promoter region.Lentiviral-mediated targeted genomic integration en-sured endogenous PIEZO2 overexpression,confirmed by mCherry fluorescence tracing coupled with flow cytometric sorting,which revealed membrane-specific localization of PIEZO2 protein(localization effi-ciency:78.49％).Quantitative PCR demonstrated a 17-fold upregulation of PIEZO2 mRNA,while Western blotting validated enhanced membrane-localized protein expression.Strikingly,PIEZO2-overex-pressing chondrocytes exhibited hallmark OA metabolic phenotypes compared to wild-type controls:typeⅡ collagen mRNA expression decreased to 50％of baseline levels,whereas matrix metalloproteinase 13(MMP13)mRNA surged by 20-fold.These alterations recapitulated the pathological matrix metabolic phenotype observed in biomechanical OA models induced by cyclic mechanical stress(10％strain,0.5 Hz,8 h/day for 2 consecutive days).Collectively,we successfully generated a human chondrocyte model with stable PIEZO2 overexpression,which faithfully mirrors mechanotransduction-driven OA progression.This engineered cellular system provides a robust platform for dissecting PIEZO2-mediated mechanosig-naling networks and advancing targeted therapeutic discovery.