Objective To evaluate the accuracy of simulated operation before the left atrial appendage ( LAA ) occlusion by filed LAA model with soft materials ,which is based on transesophageal three-dimensional echocardiography ( 3D-TEE) . Methods Silica and hydrogel were mixed to imitate cardiac tissue . Silica and hydrogel mixed materials ,silica and Tangoplus were subjected to mechanical detection and ultrasonic shear wave elastography ( SWE) . The preoperative and postoperative 3D-TEE image processing was performed on 21 patients undergoing LAA occlusion . The silica and hydrogel LAA 3D model ,silicone model and Tangoplus model were acquired to evaluate the accuracy of 3D model . LAA closure was simulated using the 3D models and the compression ratio of the device in models was compared with the value measured in operation . Results The silica and hydrogel mixed materials were successfully prepared . The elastic modulus and stress-strain curve were closer to the myocardial tissue . Twenty-one 3D printing models of three materials were obtained in 21 patients based on 3D-TEE images .There was no significant difference in the anchor zone between the 3D model and 3D-TEE ( P > 0 .05) .The 3D model measurements were consistent with the 3D-TEE measurements .The compression ratios of the decive in the 3D models of all three materials were greater than those measured in operation ,and the compression ratio of the device in the 3D model of silica and hydrogel materials had a better correlation with that measured in operation ( r =0 .900 ,P < 0 .01) .Conclusions The 3D model of LAA made of silica and hydrogel material based on 3D-TEE can improve the accuracy of the LAA occlusion simulation ,also can optimize the preparation of LAA occlusion .

Objective:To investigate the feasibility of multi-slice spiral CT (MSCT) imaging feature of gastric stromal tumor (GST) in evaluating Ki-67 index expression .Methods:The clinical and CT imaging data of 501 patients with GST confirmed by surgery and pathology were retrospectively studied in Zhongshan Hospital affiliated to Fudan University and the Affiliated TCM Hospital of Southwest Medical University from Nov 2014 to Nov 2021. By immunohistochemical results, tumors were divided into Ki-67 low expression group (Ki-67≤6%, 335 lesions) and high expression group (Ki-67>6%, 168 lesions). Multivariate logistic regression analysis was conducted.Results:Between the two groups,there were statistical differences in the longest and shortest diameter of tumor, CT value on venous phase, CT attenuation value ( Z=4.80, 4.91, 3.21, 3.29, all P<0.01) and tumor location,morphology, necrosis, ulcer, feeding artery, vascular enhancement, positive fat sign around disease, gastrointestinal bleeding ( χ2=10.77, 13.49, 8.59, 22.87, 7.59, 7.23, 7.76, 8.58, all P<0.05). Tumor ulceration positive ( OR=1.88, 95%CI: 1.17-3.03) was independent risk factor of Ki-67 high expression ( P=0.009). Gastric antrum was used as the reference for tumor location, cardia ( OR=5.41, 95% CI:1.25-23.46) was independent risk factor of Ki-67 high expression ( P=0.024). Conclusion:MSCT has a definite predictive value for the expression in Ki-67 index of GST cases.

Objective To evaluate the feasibility and accuracy of mitral valve prolapse( M VP) model made by three‐dimensional( 3D) printing based on three‐dimensional transesophageal echocardiography ( 3D‐T EE) data and the application value for mitral valvuloplasty . Methods 3D‐T EE volumetric data of 28 patients with M VP were acquired and postprocessed ,13 patients underwent mitral valve replacement and 15 patients underwent mitral valvuloplasty . A flexible material was used to made the valve 3D model by molding . T he areas of M VP identified by models were compared with surgical findings ,the circumference and the length and thickness of anterior and posterior mitral leaflets obtained from the valve specimens and the models were compared in the mitral valve replacement group . T he diameter between anterior and posterior ,the diameter between anterolaterior and posteromedial ,annulus area ,height of prolapsed leaflet and area of prolapsed leaflet were measured from 3D models and 3D‐T EE images in mitral valvuloplasty group . Surgical simulations were performed on the 3D models of the mitral valvuloplasty group ,and the water injection test was used to evaluate the surgical results and compared with the surgical results . Results 3D‐T EE volumetric data were successfully postprocessed and made as 3D M VP models in all patients . T he consistency of M VP location based on 3D models and surgical findings was 0 .92 . T he differences between the mitral valve replacement group and mitral valvuloplasty group were not significant ( P＞ 0 .05 ) . A simulation valvuloplasty was successfully performed on the 3D model in mitral valvuloplasty group ,2 patients underwent mitral valve replacement after water injection test . T he remaining 3D models successfully simulated the operation . Conclusions The M VP model made by 3D‐T EE and 3D printing technique has high feasibility and accuracy ,w hich may be promising for the mitral valvuloplasty of M VP .

Sit-stand movement is one of the most common movement behaviors of the human body. The knee joint is the main bearing joint of this movement. Thus, the dynamic analysis of knee joint during this movement has deeply positive influences. According to the principle of moment balance, the dynamics of the knee joint during the movement were analyzed. Furthermore, combined with the data obtained from optical motion capture and six-dimensional ground reaction force test, the curve of knee joint torque was calculated. To verify the accuracy of the analysis of dynamic, the human body model was established, the polynomial equations of angle and angular velocity were fitted according to the experimental data, and the knee joint simulation of the movement was carried out. The result revealed that in terms of range and trend, the theoretical data and simulation data were consistent. The relationship between knee joint torque and ground reaction force was revealed based on the variation law of knee joint torque. During the sit-stand movement, the knee joint torque and the ground reaction force were directly proportional to each other, and the ratio was 5 to 6. In the standing process, the acceleration first increased and then decreased and finally increased in reverse, and the maximum knee torque occurred at an angle of about 140°. In the sitting process, the torque was maximized in the initial stage. The results of the dynamics analysis of knee joint during sit-stand movement are beneficial to the optimal design and force feedback control of seated rehabilitation aids, and can provide theoretical guidance for knee rehabilitation training.
Humans ; Hip Joint ; Biomechanical Phenomena ; Movement ; Knee Joint ; Torque

While lobectomy is the standard surgical procedure for early-stage non-small cell lung cancer (NSCLC), sublobectomy (segmentectomy/wedge resection) has been gaining progress in early-stage peripheral NSCLC in recent years because it preserves more lung parenchyma and has the advantages of good postoperative lung function, relatively less trauma, and faster recovery. However, there has been a lack of standardized randomized clinical trials to study the survival benefits of sublobectomy. The results of a high-profile study from the USA, CALGB140503, have been the subject of intense industry debate since its presentation at the 2022 World Conference on Lung Cancer (IASLC WCLC 2022). The study, which was published in The New England Journal of Medicine on February 9, 2023, was designed to investigate whether sublobectomy was not inferior to lobectomy in terms of survival in patients with early-stage peripheral NSCLC (tumor diameter≤2 cm). The results showed that sublobectomy was not worse than lobectomy for survival in patients with T1aN0M0 peripheral NSCLC with tumor diameter≤2 cm and pathologically confirmed negative hilar and mediastinal lymph nodes. Sublobectomy, including anatomical segmentectomy and wedge resection is an effective NSCLC treatment. The results of this study provide strong evidence for the improved outcomes of sublobectomy in terms of lung function protection and are expected to promote the further use of sublobectomy. However, given the limitations of this study, whether sublobectomy, especially wedge resection, can become a standard procedure still needs to be explored. This paper presents an interpretation of this study and we invite experts in the field to discuss its usefulness in guiding clinical practice and summarise its limitations.

Adenocarcinoma, Clear Cell/pathology* ; Carcinoma in Situ ; Cell Transformation, Neoplastic ; China ; Endometriosis/pathology* ; Female ; Humans