Objective To explore the independent risk factors for early failure of internal mammary artery grafts after coronary artery bypass grafting (CABG), and to construct and preliminarily evaluate a risk prediction model for the decline of internal mammary artery bridges, optimizing postoperative risk stratification and management strategies for patients. Methods Patients who underwent CABG at Fuwai Hospital, Chinese Academy of Medical Sciences from January 2016 to January 2020 were retrospectively enrolled. The primary endpoint was the failure of the internal mammary artery bridge one year after surgery, and the secondary endpoint was major adverse cardiac and cerebrovascular events (MACCE) within five years after surgery, including all-cause death, myocardial infarction, stroke, and revascularization. Patients were divided into a failure group and a non-failure group based on whether there was early failure of the internal mammary artery bridge after surgery. Independent risk factors for the failure of the internal mammary artery bridge were explored through the least absolute shrinkage and selection operator regression and multivariate logistic regression, and a failure risk prediction model was constructed and cross-validated. Patients were stratified for MACCE risk according to the total score of independent risk factors, and the 5-year cumulative MACCE-free rate was drawn using the Kaplan-Meier method. Results A total of 657 patients were included, among whom there were 54 patients in the failure group, including 38 males and 16 females, with an average age of (61.85±8.03) years; there were 603 patients in the non-failure group, including 467 males and 136 females, with an average age of (60.45±8.23) years. Multivariate logistic regression analysis showed that non-left main lesion [OR=3.28, 95%CI (1.41, 7.62), P=0.006], pulsatility index (PI)>3.0 [OR=2.63, 95%CI (1.20, 5.75), P=0.016], quantitative flow ratio (QFR)>0.80 [OR=5.57, 95%CI (2.98, 10.41), P<0.001] and in-hospital complications [OR=4.02, 95%CI (1.59, 10.19), P=0.003] were independent risk factors for the failure of internal mammary artery grafts after CABG. Compared with the prediction model in previous literature [area under receiver operating characteristic curve was 0.632, 95%CI (0.588, 0.688)], the risk prediction model constructed with QFR>0.80, PI>3.0, non-left main lesion and in-hospital complications had a higher predictive ability for early failure of internal mammary artery grafts [area under curve: 0.758, 95%CI (0.707, 0.817); net reclassification index: 0.272, 95%CI (0.180, 0.370); comprehensive discriminative improvement index: 0.109, 95%CI (0.059, 0.158); P<0.05]. The risk score of independent risk factors for internal mammary artery graft failure demonstrated significant MACCE risk stratification efficiency in the 5-year patient follow-up, with the high-risk group showing a significantly higher incidence of MACCE compared to the medium and low-risk groups (P=0.001). Conclusion QFR>0.80, PI>3.0, non-left main lesions, and in-hospital complications are independent risk factors for early failure of internal mammary artery grafts after CABG. The constructed risk prediction model based on this has preliminary capabilities in predicting the risk of internal mammary artery graft failure and MACCE risk stratification, which is beneficial for the postoperative management of CABG patients and improving their mid-long term prognosis.

Objective:To investigate the expression,function,and clinical significance of CD24 in testicular germ cell tumors(TGCT).Methods:This study included 204 testicular germ cell tumor(TGCT)patients from the TCGA database and the TGCT-Changhai testicular germ cell tumor cohort(Changhai Hospital cohort).Prognostic analysis and multivariate analysis were employed to evaluate the association between CD24 expression and clinical characteristics.Immunohistochemistry(IHC)staining of tumor tissues was used to elucidate the mechanism by which CD24 regulated the tumor immune microenvironment(TIME)in TGCT.Finally,by analyzing the diffrences in PD-L1 expression levels and tumor-associated macrophage(TAM)M2-type cell infiltration rates between CD24 high-expression and low-expression groups,and employing the TIDE algorithm,we investigated the correlation between CD24 expression levels and immune escape scores as well as immunotherapy response rates.Results:Analysis of the TCGA database revealed that CD24 expression was significantly upregulated in TGCT with high clinical staging and M-stage(P<0.05).Compared to adjacent normal tissues,CD24 expression was significantly elevated in both primary and metastatic TGCT tissues(P<0.05).Significant differences in CD24 expression levels were observed across TNM stages and tumor progression statuses(all P<0.05).Univariate logistic regression analysis identified CD24 as a predictive factor for clinical outcomes in TGCT patients(OR=0.135,95%CI[0.035,0.516],P=0.003),and multivariate analysis further confirmed its role as an independent predictor(OR=0.057,95%CI[0.005,0.624],P=0.019).In TGCT tissues,CD24 mRNA levels correlated with immune cell markers CD206 and CD70(all P<0.05).Additionally,CD24 expression levels demonstrated significant predictive value in immune escape scoring and immunotherapy response rate assessments.Conclusions:CD24 is highly expressed in TGCT tissues and its expression is significantly correlated with the prognosis of TGCT patients,which makes it a potential new target point of biotherapy for testicular germ cell tumor patients.

Objective: To establish a microwave scattering parameter acquisition system to detect cerebral hemorrhage and cerebral ischemia animal models, and to study the non-contact rapid identification methods for the two stroke types. Methods: Rabbits were selected for modeling. Eight rabbits in the cerebral hemorrhage group were injected with autologous blood. Six rabbits in the cerebral ischemia group were treated with bilateral common carotid artery clamping and femoral artery bleeding. The measurement excitation source has a scanning frequency range of 300 kHz to 3 GHz and an intermediate frequency bandwidth of 30 kHz. The signal of the S21 phase was acquired. The collected microwave scattering signals were subjected to mean filtering, principal component analysis dimension reduction, and mean clustering and nearest neighbor analysis to realize the identification of stroke types. Results: The microwave scattering measurement method can reflect the changes of cerebral hemorrhage and cerebral ischemia. The phase of S21 decreases with the increase of blood loss and increases with the increase of ischemic duration. The results of the differential experiment showed that all 14 models were correctly identified. Conclusions The stroke identification system based on microwave scattering measurement can effectively distinguish rabbit cerebral hemorrhage model and ischemic model. This technology is low cost, portable non-invasive, simple operation and fast, which make it be a promising method for identifying pre-hospital stroke types.

Objective The three-dimensional finite element model of the normal ankle joint was established to simulate the changes of stress and displacement under stress from different directions and of different magnitudes so as to provide a theoretical basis for the biomechanical mechanism of the ankle joint injury.Methods Spiral CT scan was performed on the left ankle of a 30 year old healthy male volunteer to obtain the original CT image data.The three-dimensional digital model of ankle joint generated by Mimics and Geomagic softwares was imported into the software Ansys.The three-dimensional finite element model of ankle joint with complete anatomical structure was obtained after the main steps of meshing,central node,element linking and module loading using finite element method.Stress from different directions and of different magnitudes were loaded unto the model.The stress changes were measured by foot stress distribution measurement system.The stress changes,displacement change distribution,the stress peak value of heel are,metatarsal stress,and plantar contact stress area as well as the maximum,minimum,and contact are of the tibial articular surface contact stress were compared between the finite element model and the volunteer himself to verify the consistency.Results For the finite element model of normal ankle joint,the plantar peak stress was [(0.33 ± 0.10) MPa],the metatarsal stress was [(0.13 ± 0.21)MPa],the foot contact stress area was [(78.60 ±0.32)mm2],the tibial articular surface maximum contact stress was [(2.72 ± 0.10) MPa],the minimum contact stress was [(1.35 ±0.12)MPa],and the contact stress area was [(79.1 ± 0.14)mm2].For the volunteer,double foot plantar peak stress was [(0.35 ± 0.12)MPa],the metatarsal stress [(0.13 ±0.16)MPa],the foot contact stress area was [(77.3 ± 0.42)mm2],the tibial articular surface maximum contact stress was [(2.79 ± 0.23) MPa],the minimum contact stress was [(1.37 ± 0.20) MPa],and the contact stress area was [(79.10 ±0.14)mm2] (P ＜0.05).Therefore,the three finite element model of ankle joint was basically consistent with the real human ankle joint because of the similiar distribution,trend,and values.Conclusion The three-dimensional finite element model of normal ankle joint can objectively reflect the anatomical structure and biomechanical characteristics of the joint,which is of great value to understand the changes of the internal mechanics and ankle joint injury.