OBJECTIVE:To study the effects of new Xianling gubao capsule on fracture healing in rats,and to provide reference for seeking new formula of"to reduce stockpiles and increase efficiency(to reduce stockpiles and constant efficiency)".METHODS:Rats were randomly divided into sham operation group(distilled water),model group(distilled water),Xianling gubao capsule group (350 mg/kg),new Xianling gubao capsule low-dose,medium-dose and high-dose groups (53,105,210 mg/kg),with 14 rats in each group. Except for sham operation group,right middle femur fracture model was established under the anesthetic state. Rats were given relevant medicine 10 mL/kg intragastrically after woken,once a day,for consecutive 4 weeks.After last administration,body weights of rats were determined;the formation of callus and histopathological changes in fracture were observed;biomechanics of fracture side(fracture stress and bone crushing force)was measured. The levels of inflammatory factors (TNF-α ,IL-1 β) in serum were detected by ELISA. RESULTS:Compared with sham operation group,body weight,fracture stress and bone crushing force of fracture side were decreased significantly(P<0.05 or P<0.01),while the serum levels of TNF-α and IL-1 β were increased significantly(P<0.01). In model group,the scab was visible around the fracture,and the trabecular bone was not mature and arranged in confusion. Compared with model group,body weights of rats were increased significantly in new Xianling gubao capsule high-dose group and Xianling gubao capsule group (P<0.05);fracture stress of fracture side were increased significantly in new Xianling gubao capsule medium-dose and high-dose groups and Xianling gubao capsule group(P<0.05 or P<0.01). The serum levels of TNF-α and IL-1β were decreased significantly(P<0.01). There was no statistical significance in above indexes among new Xianling gubao capsule groups and Xianling gubao capsule group(P>0.05).The area of the callus in each group was smaller;the fracture line became blurred;the fracture trace disappeared and the number of bone trabeculae increased. The cortical layer was thickened,and a large number of capillary implants were found in the bone marrow cavity. CONCLUSIONS:New Xianling gubao capsule has a significant role in promoting fracture healing,and can effectively improve the strength of bone biomechanics and inhibit the inflammatory reaction.

Objective To study the generating algorithm of personalized external fixation model based on STL file, so as to realize the fabrication of personalized external fixation through 3D scanning, model generation and 3D printing. Compared with the traditional plaster fixation, the external fixation obtained by the proposed method has the advantages of good adhesion to the external surface of the limb, good gas permeability and light weight. Methods In order to generate a personalized external fixation model, the key generating algorithms of the model were studied. The point cloud file of the residual limb was obtained by a 3D scanner, and then was converted into an STL format file. The triangular patches were processed by cutting, offsetting, triangulating and hollowing to create an external fixation model with good gas permeability and conformable surface that is fully fitted with the body surface. Finally, the external fixation was fabricated by 3D printing. Results Using the improved point offset algorithm, the problem of severe distortion of the point offset at the plane and sharp corners was solved. Using the tangent sort method, the points on the contour ring were sorted clockwise to obtain a triangular profile. The hollowing of the model was achieved by using the typical three-dimensional "cutting tool" mathematical model and the STL file space intersection method. Conclusions The improved model generating algorithm was validated based on a wrist case, and the personalized external fixed fixation model with conformable surface was obtained. It is proved that the proposed model generating algorithm is effective and practical.

3D printing technology has unique advantages and broad application prospect in biomedicine field. In recent years, cell printing, tissue printing, and organ printing technologies h have appeared successively, and drug printing and medical device printing have been realized. For complex surgical cases, surgeons and researchers have explored a surgical program that involves 3D printing technology, and completed many clinical applications including case discussions, surgical simulations and implantation surgeries. These efforts promoted the application and development of 3D printing technology in medical field. The purpose of this paper is to describe the application and research status of 3D printing technology in medical field from the aspects of medical teaching, orthopedic surgery, stomatology, bioprinting, drug printing, medical device manufacturing, etc., and put forward the prospects for future development.

Objective To establish Cdh5-Cre ERT /Acta2-tdTomato-STOP floxed -eGFP knockin genetic tracing mice, and to investigate its application in studies on vascular endothelial cell transition in liver fibrosis. Methods Cdh5-Cre ERT mice were mated with Acta2-KI mice, and the Cdh5-Cre ERT /Acta2-KI genetic tracing mice were obtained and identified by PCR genotyping. Primary liver sinusoid endothelial cells (LSECs) were isolated and cultured, and a model of CCl 4 -induced liver fibrosis was established. LSECs and liver tissue were collected for immunofluorescent staining to observe the expression of the fluorescent proteins tdTomato and eGFP. Results After being induced by tamoxifen, LSECs and liver tissue of Cdh5-Cre ERT /Acta2-KI genetic tracing mice expressed eGFP under the conditions for epithelial-mesenchymal transdifferentiation established in vivo and in vitro, while the control group without induction expressed tdTomato alone. Conclusion The successfully established Cdh5-Cre ERT /Acta2-KI genetic tracing mice can realize the effective labeling of epithelial-mesenchymal transdifferentiation, which provides a genetic tracing basis for the diverse sources of mesenchymal myofibroblasts in liver fibrosis.