A novel electro‐active polymer actuator employing the ionic networking membrane of poly(styrene‐alt‐maleimide) (PSMI)‐incorporated poly(vinylidene fluoride) (PVDF) was developed to improve the electrical and mechanical performance of the artificial muscles. The main drawback of the previous ionic polymer‐metal composite actuator was the straightening‐back and relaxation under the constant voltage excitation. The present ionic networking membrane actuator overcomes the relaxation of the ionic polymer‐metal composite actuator under the constant voltage and also shows much larger tip displacement than that of the Nafion‐based actuator. Under the simple harmonic stimulus, the measured mechanical displacement was comparable to that of the Nafion‐based actuator. The excellent electromechanical response of the current polymer actuator is attributed to two factors: the inherent large ionic‐exchange capacity and the unique hydrophilic nano‐channels of the ionic networking membrane. The electro‐active polymer actuator of PSMI‐incorporated PVDF can be a promising smart material and may possibly diversify niche applications in biomimetic motion.

These data show that caspase-8 and -9 are involved in the apoptotic effect of celecoxib in cervical cancer cells. This requires the FADD-dependent pathway in a cell type-specific manner. In addition, NF-kappaB may play a key role in celecoxib-induced apoptosis.

Purpose Several studies reported that excessive correction of severe genu varum deformity with total knee arthroplasty or high tibial osteotomy (HTO) could result in ankle joint pain and osteoarthritis progression. However, few studies have evaluated the change in the weight-bearing-line (WBL) ratio of the ankle joint after knee arthroplasty or HTO in patients with genu varum deformities. This study aimed to investigate the change in the WBL ratio of the ankle joint and ankle joint line orientation after knee arthroplasty or HTO in patients with genu varum deformities. Methods We retrospectively evaluated 40 patients (mean age, 69.9 ± 8.0 years) with genu varum deformities of > 5°and underwent knee arthroplasty or HTO. Three radiologic parameters, including (1) the hip-knee-ankle (HKA) angle, (2) WBL ratio of the ankle joint, and (3) ankle joint line orientation relative to the ground (AJLO-G), were assessed using pre-operative and post-operative orthoradiographs. A paired t test was used to evaluate post-operative changes in the three parameters. Correlations between the change in HKA angle and that in the WBL ratio of the ankle joint and AJLO-G were analyzed. ResultsThe mean HKA angle significantly decreased post-operatively (10.6°± 5.3°to 1.1°± 3.4°; P < 0.001). The WBL ratio of the ankle joint increased from 35.8% ± 15.2% to 53.0% ± 17.4% (P < 0.001), with a lateral shift of the mechanical axis. The AJLO-G decreased with valgization of ankle orientation (7.8°± 4.8°to 0.4°± 3.8°; P < 0.001). The change in the HKA angle was significantly correlated with that in the AJLO-G (correlation coefficient = 0.716; P < 0.001) but not with the change in the WBL ratio of the ankle joint. Conclusion Knee arthroplasty and HTO corrected the genu varum deformity, which influenced the lateral shift of the WBL of the ankle joint and valgization of the ankle joint line orientation.

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