In order to obtain the normal gait for the prosthesis-carrier with the change of external environment and gait, we designed a model of dynamic ankle prosthesis and control system and introduced the strategy of centralpatterngenerator (CPG) about the moving trail of dynamic ankle prosthesis. The dynamic parts, which are incorporated in the model of dynamic ankle prosthesis, provide power in order to have anthropic function and character. The tool of Matlab/simulink was used to simulate the strategy. The simulation results showed that the strategy of CPG learning control in this study was effective and could track the reference trail rapidly and fit the moving trail of a person's normal limb. It can make the prosthetic timely regulation and action, enhance the prosthetic intelligence. It has important practical value for intelligent prosthesis development based on this analysis of technology.
In this article, we introduce the principle, describe the utilization and discuss the future development of three-dimensional printing technology for manufacturing artificial organs.
ObjectiveTo observe the effect of preoperative hyperbaric oxygen (HBO) pretreatment on systemic inflammatory response after extracorporeal circulation. MethodsA total of 30 patients who were going to receive mitral or aortic valve replacement were randomly allocated into a control group (group C, n=15) and a pretreatment group (group P, n=15).Three sessions of HBO pretreatments were given to the patients in the group P before operation. The changes of serum concentration of inflammatory factors including tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, P-selectin, intercellular adhesion molecule (ICAM)-1, heat shock protein (HSP)-70 between the two groups were compared at four time points:before incision of skin (T1), 30 min after ECC(T2), 1 h (T3) and 24 h (T4) after the end of ECC. ResultsThere was no statistical difference in the serum concentration of IL-6,TNF-α, P-selectin, ICAM-1, IL-10, and HSP-70 at T1 between the two groups (P>0.05). The level of all inflammatory factors ascended in first and descended at last in both groups, which reached a peak at T3 and descended at T4. But the serum concentration at T4 was still higher than the level at T1 (P<0.05). There was a statistical difference in serum level of HSP-70 between T4 and T1 (373.3±96.7 pg/ml vs. 316.3±55.5 pg/ml, P<0.05). There were statistical differences in serum concentration of IL-6 (141.5±25.9 pg/ml vs. 119.2±31.8 pg/ml), HSP-70 (449.8±48.3 pg/ml vs. 373.3±96.7 pg/ml), and IL-10 (64.2±8.2 pg/ml vs. 90.3±14.2 pg/ml) between the group C and the group P at T4 (P<0.05). There was no statistical difference between the two groups in postoperative ICU stay time and thoracic drainage. While time of postoperative ventilation in the group P was shorter than that in the group C with a statistical difference (11.4±5.6 days vs. 15.8±5.1 days, P<0.05). ConclusionHyperbaric oxygen pretreatment before operation can abate the bad inflammatory response after heart valve replacement surgery to some extent and strengthen the anti-inflammatory protection, thereby favoring the reduction in postoperative complications.