Objective To analyze the reverse mechano-electric effect of the layered structure of articular cartilage and its influencing factors.Methods The cartilage samples were classified according to their physiological thickness(approximately 0.4 mm for the upper layer,1 mm for the middle layer,and 0.6 mm for the lower layer).Through a non-contact external electric field testing method,how different influencing factors affected the reverse mechano-electric effect of articular cartilage was analyzed.Results When the electric field spacing decreased,water content increased,and in vitro time decreased,the displacement of normal layered cartilage in a non-contact electric field increased by 18,10,15 μm,respectively.In the case of simulated arthritis defects,as the defect depth and radius increased,the overall deviation deflection of articular cartilage gradually decreased by about 7 μm.Conclusions The three-layer cartilage differed in their reverse mechano-electricity effects,showing the greatest deflection in the middle layer at 90％water content,under 7 mm electric field spacing,and after 12 hours ex vivo.

Objective To analyze the reverse mechano-electric effect of the layered structure of articular cartilage and its influencing factors.Methods The cartilage samples were classified according to their physiological thickness(approximately 0.4 mm for the upper layer,1 mm for the middle layer,and 0.6 mm for the lower layer).Through a non-contact external electric field testing method,how different influencing factors affected the reverse mechano-electric effect of articular cartilage was analyzed.Results When the electric field spacing decreased,water content increased,and in vitro time decreased,the displacement of normal layered cartilage in a non-contact electric field increased by 18,10,15 μm,respectively.In the case of simulated arthritis defects,as the defect depth and radius increased,the overall deviation deflection of articular cartilage gradually decreased by about 7 μm.Conclusions The three-layer cartilage differed in their reverse mechano-electricity effects,showing the greatest deflection in the middle layer at 90％water content,under 7 mm electric field spacing,and after 12 hours ex vivo.

Objective:To establish a nomogram prediction model for recurrence within 2 years after radical resection of hepatocellular carcinoma (HCC) based on clinical and ultrasonographic characteristics.Methods:Clinical data from 405 HCC patients (including 327 males and 78 females), aged 60 (53, 66) years old, who underwent radical hepatectomy in the Zhongshan Hospital, Fudan University, from January to December 2021, were retrospectively collected. The patients were divided into two groups: the training group ( n=283) and the validation group ( n=122). Based on recurrence within 2 years after surgery, the 283 patients in the training group were further categorized into the recurrence group ( n=73) and the non-recurrence group ( n=210). Among the 122 patients in the validation group, 33 had recurrence within 2 years, while 89 did not. Data on age, microvascular invasion, alpha-fetoprotein (AFP), AFP lentil lectin-reactive fraction (AFP-L3), protein induced by vitamin K absence or antagonist-II (PIVKA-II), tumor number, and enhancement homogeneity were collected. Logistic regression analysis was performed on the training group to identify risk factors associated with postoperative recurrence, and a nomogram model for predicting HCC recurrence was constructed based on these factors. Calibration curves were used to compare the consistency between predicted and actual outcomes in both the training and validation groups. Results:Multivariate logistic regression analysis revealed that younger age ( OR=0.976, 95% CI: 0.953-1.000, P=0.004), higher AFP-L3 ( OR=1.066, 95% CI: 1.014-1.120, P=0.012), higher PIVKA-II ( OR=1.000, 95% CI: 1.000-1.001, P=0.042), multiple tumors ( OR=0.399, 95% CI: 0.225-0.706, P=0.038), and heterogeneous enhancement ( OR=0.472, 95% CI: 0.243-0.916, P=0.045) were significant risk factors for recurrence after partial hepatectomy in HCC patients. The nomogram constructed based on these variables had a C-index of 0.87 (95% CI: 0.81-0.93) in the training group and 0.83 (95% CI: 0.77-0.89) in the validation group. The calibration curves for predicting recurrence within 2 years after partial hepatectomy in HCC patients showed a high degree of fit in both the training and validation groups, indicating a good agreement between predicted and actual outcomes. Conclusion:The nomogram model constructed based on preoperative clinical and ultrasonographic characteristics can effectively predict the risk of recurrence within 2 years after radical resection of HCC.

Objective To explore the clinical value of virtual touch tissue quantification (VTQ) technique in the diagnosis of acute rejection of transplant kidney at different stages. Methods Clinical data of 170 renal transplant recipients were retrospectively analyzed. According to the time of VTQ examination and the occurrence of acute rejection after renal transplantation, the recipients within 4 weeks and after 4 weeks post-renal transplantation were assigned into the normal renal function group (n=41, 51) and acute rejection group (n=22, 56). Clinical ultrasound parameters at different stages after renal transplantation were compared between two groups. The diagnostic value of ultrasound parameters in acute rejection at different stages after renal transplantation was evaluated. Results Within 4 weeks post-renal transplantation, the resistance index (RI) and shear wave velocity (SWV) in the acute rejection group were significantly higher than those in the normal renal function group (both P < 0.001). After 4 weeks post-renal transplantation, the SWV in the acute rejection group was significantly higher than that in the normal renal function group (P < 0.001). The area under curve (AUC) of RI and SWV in the diagnosis of acute rejection were 0.729 and 0.803 respectively within 4 weeks post-renal transplantation, which were 0.478 and 0.794 respectively after 4 weeks post-renal transplantation. The diagnostic value of SWV was higher than RI (P < 0.05). The cutoff value of SWV in the diagnosis of acute rejection within 4 weeks post-renal transplantation was considerably higher than that after 4 weeks post-renal transplantation. Conclusions VTQ technique can effectively assist in diagnosing acute rejection of transplant kidney at different stages.

Objective To explore the characteristics and differences of micro-perfusion between patients after transplant kidney with stable renal function,acute rejection and chronic rejection by contrast enhanced ultrasound (CEUS) quantifying.Methods Thirty-three patients with stable renal function,27 patients with acute rejection and 14 patients with chronic rejection were enrolled.The perfusion parameters of region of interest in renal cortex and medulla were obtained by CEUS offline data quantitative analysis software.The perfusion parameters in stable renal function group were compared with those in acute rejection and chronic rejection groups;furthermore,the value of color Doppler and CEUS in the diagnosis of chronic rejection was explored and compared.Results As for resistance index RI on color Doppler,it made no statistical difference among three groups (P＞0.05).The perfusion parameters derived from CEUS quantitative analysis and Color Doppler parameter resistance index (RI) were not statistically different among renal function stabilization,acute rejection and chronic rejection groups (P＞0.05);as compared with stable renal function group,there were marked reductions in peak intensity of cortex (PIc),peak intensity of medulla (PIm),ascending slope of cortex (a3c),ascending slope of medulla (a3m) and area under the curve of cortex (AUCc) in chronic rejection group.And mean transit time of cortex (MTTc) and mean transit time of medulla (MTTm) became significantly prolonged (P＜ 0.05).Except for a3m,PIc and PIm were not significantly different between stable renal function and acute rejection groups (P＜ 0.05).As compared with acute rejection group,MTTc and MTTm were significantly prolonged in chronic rejection group while AUCm and PIm declined markedly (P＜0.05).When PIm＜26.7dB,the diagnostic efficiency of chronic rejection was the highest and the sensitivity and specificity were 85.7％ and 72.7％ respectively.Conclusions As compared with color Doppler,CEUS quantitative parameters based on S-G filter theory can evaluate the micro-perfusion of transplant kidney more precisely and may provide diagnostic clue for chronic rejection.

Objective To analyze the risk factors for in-hospital mortality in patients aged over 65 years undergoing heart valve surgery combined with coronary artery bypass grafting(CABG).Methods Between February 2002 and September 2014,540 patients aged over 65 years undergoing heart valve surgery combined with CABG in our institute were retrospectively studied.Univariate analyses and multivariate logistic regression analyses were performed to explore risk factors associated with in-hospital mortality.Results Overall in-hospital mortality was 4.26％.Univariate analysis depicted that chronic obstructive pulmonary disease (COPD) (P =0.001),last serum creatinine (P =0.043),unstable angina(P =0.046),Canadian Cardiovascular Society 111-ⅣV (P =0.005),number of diseased coronary vessels (P =0.043),cardiopulmonary bypass time-delayed (P =0.003),post-operative morbidity (P =0.000) had a significant impact on in-hospital mortality.Multivariate logistic regression analysis revealed that COPD (P =0.005,OR =5.598),CPB time-delayed (P ＜ 0.001,OR =1.011),re-exploration (P ＜0.001,OR =15.813),malignant arrhythmia (P =0.014,OR =4.900) were independent risk factors of in-hospital mortality.Conclusion The present research demonstrates that COPD,CPB time-delayed,re-exploration and malignant arrhythmia dramatically impacted the in-hospital mortality of patients aged over 65 years undergoing combined heart valve surgery and CABG.

Objectives: To analyze clinical characteristics with the early and late prognosis in elder patients with combined aortic valve replacement (AVR) and coronary artery bypass grafting (CABG).
Methods: A total of 232 patients≥65 years of age who received AVR-CABG in our hospital from 2004-02 to 2014-09 were retrospectively analyzed. The risk factors affecting the early and late prognosis in those patients were studied by multivariate Logistic regression analysis and Cox proportional hazards model.
Results: The in-hospital death happened in 7/232 (3.0%) patients, early post-operative complication with prolonged mechanical ventilation time was 28 (12.1%) and bleeding was 14 (6.0%). The follow-up study was conducted in 225/232 (97.0%) survived patients from 3 months to 10 years at the mean of (41.2 ± 29.0) months; 6 (2.7%) patients had cardiac death, the major late post-operative adverse events were cardiac dysfunction (III to IV) or recurrence of angina (8.9%). Multivariate Logistic regression analysis revealed that female (P=0.019, OR=2.576), pre-operative atrial ifbrillation (AF) (P=0.012, OR=3.541) and CPB time (P=0.000, OR=3.781) were the independent risk factors affecting early post-operative outcome. Cox proportional hazards model presented that hyperlipidemia (P=0.025, HR=2.535), smoking (P=0.009, HR=3.414) and the history of PCI (P=0.013, HR=3.562) were the independent risk factors inlfuencing late prognosis of AVR-CABG.
Conclusion: The overall effect of AVR-CABG in elder patients was satisfactory. Female, pre-operative AF, CPB time may affect the early post-operative outcome, while hyperlipidemia, smoking and PCI history could inlfuence the long-term prognosis in relevant patients.

Objective To evaluate the diagnostic value of virtual touch tissue quantification (VTQ) in the diagnosis of renal allograft fibrosis.Methods The renal allografts of 82 patients with biopsies or nephrectomy were assessed by virtual touch quantification.The renal allograft fibrosis was categorized according to the 2005 updated Banff criteria for a G0～G3 grade.All the results were compared among four groups.Results The mean SWV values in G0～G3 were (2.39 ± 0.31)m/s,(2.45 ± 0.34)m/s,(2.58 ± 0.18) m/s,(3.11 ± 0.40)m/s,respectively.There were no significant differences in the mean SWV value between G0 and G1 group,or between G1 and G2 group(P ＞0.05).There were significant differences in the mean SWV value between G0～G2 and G3 group,or between G0 and G2 group(P ＜0.05).Stiffness of renal allograft was significantly correlated to the mean SWV value (Spearman r =0.671,P ＜0.001).According to the area under the ROC curve,the sensitivity and specificity of SWV (area under ROC curve =0.847,cut-off=2.64 m/s) for grade ≥G2 was 78.9％ and 79.5％ respectively.Conclusions Stiffness measured by VTQ reflects the interstitial fibrosis in renal allograft.VTQ technique might be a new tool to identify patients with chronic allograft injury.

Objective:To investigate the clinical value of color Doppler flow imaging (CDFI)for evaluating transplant renal artery stenosis (TRAS) .Methods:Clinical data and ultrasonography results of 19 patients with suspected TRAS ,which were evaluated by CDFI ,were retrospectively analyzed .CDFI indexes included the peak systolic velocity (PSV) in the main renal artery ,a ratio of the PSV in the main renal artery to that in the interlobar arteries (the POST‐ PSV ratio) and the resistant index (RI) in the interlobar arteries .The randomly enrolled 25 patients with stable transplant renal function were set as control group .The examination results were evaluated by “gold standard” digital subtraction angiography (DSA ) or magnetic resonance angiography .Paeients with TRAS diagnosed by DSA or MRA were set as stenosis group .Results:Thirteen casts showed stenosis .There were 2 false positive cases for CDFI diagnosis .And 4 cases did not undergo DSA or MRA examination . Compared with that in the control group ,the PSV of the main renal artery and the POST‐ PSV ratio in the stenosis group increased significantly(P<0 .001) ,however ,the RI in the interlobar arteries decreased significantly(P<0 .001) .CDFI indexes remarkably changed after the TRAS patients had undergone renal artery dilatation or stent implantation .Conclusions:CDFI is a reliable first choice method for screening transplant renal artery stenosis .

Objective To evaluate the value of quantitative analysis of contrast‐enhanced ultrasonography (CEUS) in differentiating acute rejection(AR) from acute tubular necrosis(ATN) of transplant kidney. Methods Total of 67 kidney recipients were examined with conventional US and CEUS. Biopsies were performed in 37 patients, 26 patients were with AR, 11 with ATN, 30 patients as control group. The hemodynamic parameters (PSV and RI) were measured on infrarenal artery with conventional US, while CEUS quantitative analysis was performed on the cortex, pyramid and interlobar artery by time‐intensity curve (TIC). TIC parameters including rise time (RT ), time to peak (TTP), mean transit time (mTT ) were compared among three groups. In addition, the reproducibility of TIC parameters was evaluated. Results The RI in AR group was significantly higher than that in control group, but there were no significant differences of RI between AR and ATN groups. TIC parameters including RT, TTP were with high reproducibility (ICC> 0 7.5). Compared to the other two groups, the RT and TTP of the pyramid, ΔRTm‐c, and ΔTTPm‐c were significantly longer in AR group, the receiver operating curves (ROC) analysis demonstrated that ΔRTm‐c had the highest accuracy and RI had the lowest accuracy for detecting AR(areas under the curve were 0 7.86, 0 7.56, 0 7.49, 0 7.36 and 0 4.98, respectively). High sensitivity and specificity(78 3.% and 73 5.%, respectively) were shown when using 4 6.2 s as a cutoff point of ΔRTm‐c to diagnose AR. Conclusions Quantitative analysis of CEUS could detected the changes of the microcirculation perfusion in kidney grafts with AR and ATN, which might be superior in the diagnosis of AR compared with conventional US.