1.The Effect of Different Heights of Salto Tibial Components on Stability of the Bone-Prosthesis Interface after Total Ankle Replacement Surgery
Shengyu PAN ; Da LU ; Yangyang XU ; Yong WU ; Le ZHANG ; Xueqing WU ; Hui DU ; Liangpeng LAI ; Baoqing PEI
Journal of Medical Biomechanics 2025;40(2):428-434
Objective To investigate the biomechanical characteristics of Salto Talaris tibial components with different heights at the bone-prosthesis interface during different gait support phases after total ankle replacement.Methods An ankle joint model was reconstructed using a weight-bearing CT from a 61-year-old female patient with ankle arthritis,and Salto Talaris tibial components with different heights(5,7,9,11 mm)were modelled to simulate the loading of the tibial-prosthesis during four gait support phases,and to analyse the micromotion and stresses at the bone-prosthesis interface.Results The 11 mm and 9 mm models had a poorer prosthesis stability,with the peak micromotion exceeding 50 μm and the peak internal tibial stresses of 30.75 MPa and 29.86 MPa,respectively,which exceeded the yield stress of the cancellous bone.The tibial stresses of the 7 mm and 5 mm models were within reasonable ranges and the average peak micromotions were only 42.66 μm and 40.32 μm.In contrast,the initial stability of the 5 mm model prosthesis was the best.Conclusions For total ankle replacement with Salto prosthesis,the height of the tibial component should be chosen appropriately,and the optimal height was about 5 mm.Excessive flexion and extension activities of the ankle joint should be avoided to maintain the stability of the prosthesis after surgery.This study provides a theoretical basis for the improvement of the structural parameters of the Salto prosthesis,which is valuable for the selection of clinical surgical prostheses and helps to improve the results of total ankle replacement.
2.The Effect of Different Heights of Salto Tibial Components on Stability of the Bone-Prosthesis Interface after Total Ankle Replacement Surgery
Shengyu PAN ; Da LU ; Yangyang XU ; Yong WU ; Le ZHANG ; Xueqing WU ; Hui DU ; Liangpeng LAI ; Baoqing PEI
Journal of Medical Biomechanics 2025;40(2):428-434
Objective To investigate the biomechanical characteristics of Salto Talaris tibial components with different heights at the bone-prosthesis interface during different gait support phases after total ankle replacement.Methods An ankle joint model was reconstructed using a weight-bearing CT from a 61-year-old female patient with ankle arthritis,and Salto Talaris tibial components with different heights(5,7,9,11 mm)were modelled to simulate the loading of the tibial-prosthesis during four gait support phases,and to analyse the micromotion and stresses at the bone-prosthesis interface.Results The 11 mm and 9 mm models had a poorer prosthesis stability,with the peak micromotion exceeding 50 μm and the peak internal tibial stresses of 30.75 MPa and 29.86 MPa,respectively,which exceeded the yield stress of the cancellous bone.The tibial stresses of the 7 mm and 5 mm models were within reasonable ranges and the average peak micromotions were only 42.66 μm and 40.32 μm.In contrast,the initial stability of the 5 mm model prosthesis was the best.Conclusions For total ankle replacement with Salto prosthesis,the height of the tibial component should be chosen appropriately,and the optimal height was about 5 mm.Excessive flexion and extension activities of the ankle joint should be avoided to maintain the stability of the prosthesis after surgery.This study provides a theoretical basis for the improvement of the structural parameters of the Salto prosthesis,which is valuable for the selection of clinical surgical prostheses and helps to improve the results of total ankle replacement.
3.Construction and validation of a risk prediction model for extubation due to complications of totally implantable access port
Yangyang ZHANG ; Hongxin ZHANG ; Na ZHANG ; Hua HE ; Xiuwei DA
Chinese Journal of Nursing 2024;59(20):2455-2462
Objective To analyze the status quo and influencing factors of extubation due to complications of totally implantable access port in patients with liver cancer undergoing chemotherapy,to establish a risk prediction model,and to conduct internal validation of the model.Methods This study was a prospective nested case-control study.The patients with liver cancer undergoing chemotherapy for maintenance of totally implantable access port in a tertiary hospital in Shaanxi from October 2021 to September 2023 were selected as the investigation subjects.Patients with extubation due to complications were selected as an extubation due to complications group,and patients with planned extubation were randomly selected as a planned extubation group according to the matching number of 1∶10.Univariate analysis and Logistic regression analysis were used to explore the influencing factors of extubation due to complications.A visual nomogram risk prediction model was established,and the model was internally verified by receiver operating characteristic(ROC)curve,calibration curve and Hosmer-Lemeshow fit test.Results The incidence of extubation due to complications of totally implantable access port in patients with liver cancer undergoing chemotherapy was 7.0%.Infection(36.7%)and thrombosis(30.0%)were the main causes of extubation due to complications.BMI,TNM staging,diabetes,the number of catheter lumens in the access port and the chemotherapy times were the main influencing factors of extubation due to complications(P<0.05).The area under ROC curve of the prediction model was 0.871;the best cut-off value was 0.106;the sensitivity was 0.800;the specificity was 0.820.The average absolute error between the actual and predicted values of the calibration curve was 0.011,and the calibration curve was close to the ideal curve.The Hosmer-Lemeshow goodness of fit test was x2=2.913(P=0.940).Conclusion The incidence of extubation due to complications of totally implantable access port in patients with liver cancer undergoing chemotherapy is low,and infection and thrombosis are the main reasons.Patients with a BMI≥ 24,TNM stage Ⅲ or Ⅳ,diabetes,double catheter lumens in the access port,and chemotherapy times>5 were at higher risk of extubation due to complications.The risk prediction model developed in this study demonstrates good predictive accuracy,and it can serve as a valuable tool for healthcare professionals in early identification of patients at risk for extubation due to complications.
4.Microbial production of poly (glycolate-co-lactate-co-3-hydroxybutyrate) from glucose and xylose by Escherichia coli.
Yangyang DA ; Wei LI ; Lilong SHI ; Zhengjun LI
Chinese Journal of Biotechnology 2019;35(2):254-262
Escherichia coli was metabolically engineered to produce poly(glycolate-co-lactate-co-3-hydroxybutyrate) using glucose and xylose as carbon sources. The combinatorial biosynthetic route was constructed by the overexpression of a series of enzymes including D-tagatose 3-epimerase, L-fuculokinase, L-fuculose-phosphate aldolase, aldehyde dehydrogenase, propionyl-CoA transferase, β-ketothiolase, acetoacetyl-CoA reductase, and polyhydroxyalkanoate synthase. Overexpression of polyhydroxyalkanoate granule associated protein significantly improved biopolymer synthesis, and the recombinant strain reached 3.73 g/L cell dry weight with 38.72% (W/W) biopolymer content. A co-culture engineering strategy was developed to produce biopolymer from a mixture of glucose and xylose, achieving 4.01 g/L cell dry weight containing 21.54% (W/W) biopolymer. The results of this work offer an approach for simultaneously utilizing glucose and xylose and indicate the potential for future biopolymer production from lignocellulosic biomass.
3-Hydroxybutyric Acid
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Escherichia coli
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Glucose
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Glycolates
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Lactates
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Metabolic Engineering
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Polyesters
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Xylose
5.The histological underestimation of stereotactic core needle biopsy in breast lesions
Jie MA ; Jianmin XU ; Mu DU ; Yangyang ZHOU ; Da ZANG ; Zhong YANG ; Dongxian ZHOU ; Peicheng MAI
Chinese Journal of Radiology 2008;42(6):597-600
Objective To analyze the histological underestimation of stereotactic core needle biopsy (SNCB).and tO attract clinicians' attention.Methods SNCB was performed in 146 patients with 179 lesions from September 2000 to June 2005.and 21 lesions were underestimated histologically.0f 21 nonpalpable breast lesions(NPBL).6 lesions were diagnosed as BI-RADS nl,12 8S BI-RADS Ⅳ,3 as BI-RADS V according to BI-RADS before biopsy.Mammography showed 16 lesions with calicification, 2 cases with masses,1 case with asymmetry density and 2 cases with stellate sign.Results Eleven lesions diagnosed as fibrocystic disease with atypical ductal hyperplasia by biopsy were proved to be ductal carcinoma in situ (DCIS)in 7 lesions and early infiltration in 4 lesions by pathology.3 lesions diagnosed as severe atypical hyperplasia by biopsy were finally proved to be 1 carcinoma in situ and early infiltration in 2 lesions by pathology.3 lesions diagnosed as DCIS by biopsy were invasive carcinoma.4 lesions diagnosed papillary lesions by biopsy and finally were 1 carcinoma in situ,1 early infiltration,1 infiltrating ductal carcinoma and l intraductal papillary adenocarcinoma.Conclusion The histological underestimation of SCNB Was related to the stereotactic location technology,lesion and doctor'S understanding,the radiologist should master the biopsy skills.

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