Abstract： Diseases prognosis is often influenced by multiple factors, and some intricate non-linear relationships exist among those factors. Artificial neural network （ANN）, an artificial intelligence model, simulates the work mode of biological neurons and has a b capability to analyze multi-factor non-linear relationships. In recent years, ANN is increasingly applied in clinical medical fields, especially for the prediction of disease prognosis. This article focuses on the basic principles of ANN and its application in disease prognosis research.
OBJECTIVE: To fabricate artificial human skin with the tissue engineering methods. METHODS: The artificial epidermis and dermis were fabricated based on the successful achievements of culturing human keratinocytes(Kc) and fibroblasts (Fb) as well as fabrication of collagen lattice. It included: 1. Culture of epidermal keratinocytes and dermal fibroblasts: Kc isolated from adult foreskin by digestion of trypsin-dispase. Followed by comparison from aspects of proliferation, differentiation of the Kc, overgrowth of Fb and cost-benefits. 2. Fabrication of extracellular matrix sponge: collagen was extracted from skin by limited pepsin digestion, purified with primary and step salt fraction, and identified by SDS-PAGE. The matrix lattice was fabricated by freeze-dryer and cross-linked with glutaraldehyde, in which the collagen appeared white, fibrous, connected and formed pores with average dimension of 180 to 260 microns. 3. Fabrication artificial human skin: The artificial skin was fabricated by plating subcultured Kc and Fb separately into the lattice with certain cell density, cultured for one week or so under culture medium, then changed to air-liquid interface, and cultured for intervals. RESULTS: The artificial skin was composed of dermis and epidermis under light microscope. Epidermis of the skin consisted of Kc at various proliferation and differentiation stages, which proliferated and differentiated into basal cell layer, prickle cell layer, granular layer, and cornified layer. Conifilament not only increased in number, but also gathered into bundles. Keratohyalin granules at different development stages increased and became typical. The kinetic process of biochemistry of the skin was coincide with the changes on morphology. CONCLUSION: Tissue engineered skin equivalent has potential prospects in application of repairing skin defect with advantages of safe, effective and practical alternatives.
With the development of society and the progress of technology, artificial intelligence (AI) and big data technology have penetrated into all walks of life in social production and promoted social production and lifestyle greatly. In the medical field, the applications of AI, such as AI-assisted diagnosis and treatment, robots, medical imaging and so on, have greatly promoted the development and transformation of the entire medical industry. At present, with the support of national policy, market, and technology, we should seize the opportunity of AI development, so as to build the first-mover advantage of AI development. Of course, the development and challenges are coexisted. In the future development process, we should objectively analyze the gap between our country and developed countries, think about the unfavorable factors such as AI chips and data problems, and extend the application and service of AI and big data to all links of medical industry, integrate with clinic fully, so as to better promote the further development of AI medicine treatment in China.
Objective To study the degradable properties of 3D-SC artificial skin in vitro. Methods The 3D-SC artificial skin materials wererespectively immersed into the solutions of 0.9% normal saline (control group), pancreatic tissue liquid (experimental group 1), physiological buffer (Hanks balanced salt solution，experimental group 2) and 0.2 mol/L phosphate buffer (pH 7.4，experimentalgroup 3), and the degradation was carried out at 37℃. The quality lost ratioswere determined on the 3rd day, the 5th day, the 7th day, the 9th day, 11th dayand 14th day in the experimental group 1, while on the 3rd day, 7th day, 14th day, 15th day, 21st day and 30th day in the other groups. Results The 3D-SC artificial skin was degraded completely in pancreatic tissue liquid about within 14 days in the experimental group 1; in the control group, and in the experimental groups 2 and 3, the degradation ratios were 868%±2.30%,28.51%±10.68% and 7.35%±0.61% on the 14th day; 71.83%±2.58%, 91.32%±1.87% and 75.64%±6.13% on the 15th day, being significant difference between the control group and the experimental group 2(Plt;0.01); and 91.87%±8.15%, 95.62%±1.36% and 92.10%±2.26% on the 30th day, being no significant differences between these 3 groups(Pgt;0.05), respectivelies. Conclusion The 3D-SC artificial skin materials have good degradable properties. The trend of degradation speed is from slow to quick and then to slow without enzyme.
Abstract The fracture of the prosthetic stem after prosthetic replacement of femoral head is not rare. In this study, the photoeastic instrument was used to study the stress distribution on the prosthetic stem following its insertion and to analyse the factors influencing the fracture of the stem. Through the examination of 9 places in 8 cases, it was found that:(1) The removal of femoral calcar and the inframedullary filling of the bone cement directly influenced the stress distribution. (2) The valgus or varus condition of the prosthesis would lead to stress concentration on the stem. (3) Once lossening of the prosthesis occured it would change the preliminary installingstress distribution in the upper femur which would lead to fatigue fracture. Ths experimental data and clinical observation would provide scientific basis forthe prevention of fracture of prosthetic stem following prosthetic replacement of femoral head.
Objective To explore the effect of minimally invasive and mini-incision surgery (MIS) in total hip arthroplasty (THA) on late osteonecrosis of femoral head (ONFH). Methods From March 2003, Eighteen patients (22 hips) with ONFH underwent MIS in THA. Their ages ranged from 24to 57 years, including 13 males and 5 females. The mean body mass index ranged from 17.1 to 30.1(24.6 on average). The Harris hip score was 46 points before operation. Modified posterior-lateral approach was adopted, and the MIS THA was performed by cementless prosthesis. As a comparison, 18 patients (22 hips) were performed by conventional THA at the same period. The data, including bleeding volume during operation, incision length, operative time, and postoperative function recovery, were compared. Results Follow-ups were done for 6 to 20 months (11 months on average). Dislocation occurred in one patient that underwent conventional THA 2 days after operation. No complication occurred in MIS THA group. The incision lengths ranged from 8.7 to 10.5 cm (9.3 cm on average) in MIS THA group, being statistically different (Plt;0.01). There was no significant difference in Harris scoring of the function between the two groups both before the operation and after the operation (Pgt;0.05). The operative time was almost the same, but the bleeding volume in MIS THA group was less (Plt;0.05). The function recovery was faster in MIS THA group.Conclusion The MIS THA is an alternative to the treatment of late ONFH. The advantages of MIS THA are fewer trauma, less bleeding volume, and faster recovery. The MIS THA should be performed by surgeons with rich experiences in THA and hospitals with necessary instruments.
Objective To study the feasibility of transplanting human saphanous vein endothelial cells to luminal surface of blood vessel prosthesis and to play a theoretical foundation for the clinical application of autologous endothelial cell transplantation. Methods Human saphanous vein endothelial cells were harvested with 0.1% collagenase and cultivated in vitro for 13.08±1.24 days. The cultures were confirmed as endothelial cells with the fourescent linked anti-Ⅷ antigen antibodies. The content of both 6-keto-PGF1α and Von Willebrand factor (vWF) in the supernatant were detected with ELISA and radioimmunoassay. The multiplied cells were lined in vitro onto the luminal surface of expanded polytetraflouroethylene (ePTFE) grafts precoated with fibrin glue and fibronectin, then cultivated again for 9 days. Results 11.46±2.69×１０６ of available endothelial cells could be regularly obtained, the number of endothelial cells increased 147.93±88.68 times when culture were terminated. All the cells diploid cells with a purity of 99%. The content of both 6-keto-PGF1α and vWF in the media showed no significant difference between the primary and subculture passages. The luminal surface of grafts was covered completely by a spindlelike endothelial monolayer and an even fibrin glue matrix could be seen underneath. Conclusion Endothelial cells derived from human saphanous veins might be feasible to be transplanted onto the luminal surface of ePTFE and present a potential clinical application.
OBJECTIVE: To study the effect of platelet-rich plasma in the repair of bone defect. METHODS: Segmental bone defects of 1 cm were created in the mid-upper part of bilateral radius of 24 New Zealand white rabbits. One side was randomly chosen as the experimental side, which was filled with artificial bone with platelet-rich plasma (PRP). The other side filled with artificial bone without PRP as the control. After 2, 4, 8 and 12 weeks of implantation, the gross, radiological, histological observations, and computer graphic analysis were performed to investigate the bone healing of the defect in both sides. RESULTS: Two weeks after operation, new bone and fibrous tissue formation in both the experimental and the control sides were observed only in the areas adjacent to the cut ends of the host bone, but the amount of new tissue in the experimental side was much more than that in the control side. In the 4th and 8th weeks, the surface of the artificial bone was covered with a large amount of new bones, the artificial bone was bridged tightly with the host bone by callus in the experimental side, while new bone was limited mainly in the cut ends and was less mature in the control side. In the 12th weeks, bone defects were entirely healed in the experimental side, which were covered completely with cortical bone, while new bone formation was only observed in the ends of artificial bone and there were not continuous bone callus on the surface in the control side. CONCLUSION: Artificial bone with PRP is effective in the repair of segmental bone defects, and PRP could improve the healing of bone defect.