Objective:To evaluate the expression of semaphorin 5B (SEMA5B) in gastric adenocarcinoma and its relationship with prognosis.Methods:In November 2019, the clinicopathological characteristics and SEMA5B mRNA expression data of 341 patients with gastric adenocarcinoma were collected through TCGA database. The relationship between SEMA5B expression in gastric adenocarcinoma tissues and clinical pathologic features and overall survival were analyzed. Gene Set Enrichment Analysis (GSEA) was used to analyze the signaling pathways regulated by SEMA5B.Results:The expression level of SEMA5B mRNA in 341 gastric adenocarcinoma tissues was 0.577±0.587, in adjacent normal tissues was 0.132±0.075, the difference was statistically significant ( P<0.001). The median survival time of 109 patients with high expression of SEMA5B mRNA was 14.5 months, 232 patients with low expression of SEMA5B mRNA was 17.9 months ( P=0.047). Univariate analysis showed that the expression of SEMA5B mRNA was correlated with histological grade and T stage ( P<0.05). The multivariate analysis revealed that age<65 years remained independently associated with overall survival, with a hazard ratio( HR) of 1.042 (95% CI: 1.021-1.064). The multivariate analysis revealed that high expression of SEMA5b mRNA remained independently associated with overall survival, with a HR of 1.195 (95% CI: 0.925-2.551). GSEA showed that malignant tumor signaling pathways ( P=0.008), MAPK signaling pathways ( P=0.047) and Notch signaling pathways ( P=0.029) were differentially enriched in SEMA5B highly expressed phenotype. Conclusions:SEMA5B expression may be a potential prognostic molecular marker for prognosis of GAC patients. Moreover, malignant tumor signaling pathway, MAPK signaling pathway and Notch signaling pathway may be the key pathway regulated by SEMA5B in GAC.

BACKGROUND:With social progress,the incidence rate of knee osteoarthritis is getting higher and higher in the face of the rapidly developing aging problem in the social population,and the number of total knee replacement operations is gradually increasing. OBJECTIVE:To study the relationship between prosthesis size and stress shielding by improving the tibial prosthesis base. METHODS:A female patient with severe knee osteoarthritis was selected.Based on Mimics,through extracting the bone structure of the knee joint and simulating the total knee replacement surgery,osteotomy,positioning,and implantation operations were carried out to establish the geometric modeling of the total knee replacement prosthesis(including the femoral prosthesis,tibial bracket,and tibial pad),and improve the design of the tibial prosthesis base,analyze the effect of different tibial prosthesis bases on stress shielding of surrounding bone tissue. RESULTS AND CONCLUSION:(1)Compared with single-stem tibial intramedullary stem prosthesis,the design of four-post tibial intramedullary stem prosthesis created a certain degree of stress shielding around the short stem.However,compared with a thicker single long stem,this stress shielding effect was significantly reduced,and the load was evenly distributed among the four short stems,so there was no stress concentration at the bottom of the pile.(2)The design with a rectangular hole in the middle not only provided relatively good stability,but also helped to reduce stress shielding of cancellous bone to a certain extent,with a reduction rate of 77.5%.(3)Compared with a single-stem tibial intramedullary stem prosthesis,both the four-post tibial intramedullary stem prosthesis and the four-post tibial intramedullary stem prosthesis with a hole in the middle have good stability,which can reduce stress shielding to a certain extent without causing stress concentration,providing theoretical guidance for the design of the tibial intramedullary stem.

Objective:To evaluate the expression of semaphorin 5B (SEMA5B) in gastric adenocarcinoma and its relationship with prognosis.Methods:In November 2019, the clinicopathological characteristics and SEMA5B mRNA expression data of 341 patients with gastric adenocarcinoma were collected through TCGA database. The relationship between SEMA5B expression in gastric adenocarcinoma tissues and clinical pathologic features and overall survival were analyzed. Gene Set Enrichment Analysis (GSEA) was used to analyze the signaling pathways regulated by SEMA5B.Results:The expression level of SEMA5B mRNA in 341 gastric adenocarcinoma tissues was 0.577±0.587, in adjacent normal tissues was 0.132±0.075, the difference was statistically significant ( P<0.001). The median survival time of 109 patients with high expression of SEMA5B mRNA was 14.5 months, 232 patients with low expression of SEMA5B mRNA was 17.9 months ( P=0.047). Univariate analysis showed that the expression of SEMA5B mRNA was correlated with histological grade and T stage ( P<0.05). The multivariate analysis revealed that age<65 years remained independently associated with overall survival, with a hazard ratio( HR) of 1.042 (95% CI: 1.021-1.064). The multivariate analysis revealed that high expression of SEMA5b mRNA remained independently associated with overall survival, with a HR of 1.195 (95% CI: 0.925-2.551). GSEA showed that malignant tumor signaling pathways ( P=0.008), MAPK signaling pathways ( P=0.047) and Notch signaling pathways ( P=0.029) were differentially enriched in SEMA5B highly expressed phenotype. Conclusions:SEMA5B expression may be a potential prognostic molecular marker for prognosis of GAC patients. Moreover, malignant tumor signaling pathway, MAPK signaling pathway and Notch signaling pathway may be the key pathway regulated by SEMA5B in GAC.