Biological Fixation of Bioactive Bone Cement in Vertebroplasty: The First Clinical Investigation of Borosilicate Glass (BSG) Reinforced PMMA Bone Cement.

PMMA bone cement has been clinically used for decades in vertebroplasty due to its high mechanical strength and satisfactory injectability. However, the interface between bone and PMMA is fragile and more prone to refracture in situ because PMMA lacks a proper biological response from the host bone with minimal bone integration and dense fibrous tissue formation. Here, we modified PMMA by incoporating borosilicate glass (BSG) with a dual glass network of [BO3] and [SiO4], which spontaneously modulates immunity and osteogenesis. In particular, the BSG modified PMMA bone cement (abbreviated as BSG/PMMA cement) provided an alkaline microenvironment that spontaneously balanced the activities between osteoclasts and osteoblasts. Furthermore, the trace elements released from the BSGs enhanced the osteogenesis to strengthen the interface between the host bone and the implant. This study shows the first clinical case after implantation of BSG/PMMA for three months using the dual-energy CT, which found apatite nucleation around PMMA instead of fibrous tissues, indicating the biological interface was formed. Therefore, BSG/PMMA is promising as a biomaterial in vertebroplasty, overcoming the drawback of PMMA by improving the biological response from the host bone.

Achieving smooth motion and high-speed for piezoelectric stick-slip actuator based on the two-stage lever principle.

With the development of the precision manufacturing industry, actuators' performance requirements are increasingly demanding. However, stick-slip actuators still have the problems of backward motion and low motion speed at low frequencies. In this paper, to decrease the backward motion and achieve high speed at low frequencies, a linear piezoelectric stick-slip actuator is designed based on the two-stage lever principle. Theoretical and numerical investigations are used to optimize the flexible hinge of the stick-slip actuator. Experimental results indicate that the motion slider can achieve a smooth motion. The backward rate can even drop to 0. The maximum motion speed was 124.83 mm/s at 1600 Hz. The motion speed of the designed actuator was higher than that of previous stick-slip actuators at the same frequency. In addition, the load capacity of the prototype is tested. Based on different loads, the load matching is achieved by an auxiliary piezoelectric-stack, where the maximum horizontal load was 2.3 N. According to the comparison with previous actuators, the designed prototype can achieve high speed at low frequencies. Furthermore, the displacement curves show good smoothness. These characteristics will be helpful for the practical application of stick-slip piezoelectric actuators.

Oriented Polyaniline Nanowire Arrays Grown on Dendrimer (PAMAM) Functionalized Multiwalled Carbon Nanotubes as Supercapacitor Electrode Materials.

At present, PANI/MWNT composites have been paid more attention as promising electrode materials in supercapacitors. Yet some shortcomings still limit the widely application of PANI/MWNT electrolytes. In this work, in order to improve capacitance ability and long-term stability of electrode, a multi-amino dendrimer (PAMAM) had been covalently linked onto multi-walled carbon nanotubes (MWNT) as a bridge to facilitating covalent graft of polyaniline (PANI), affording P-MWNT/PANI electrode composites for supercapacitor. Surprisingly, ordered arrays of PANI nanowires on MWNT (setaria-like morphology) had been observed by scanning electron microscopy (SEM). Electrochemical properties of P-MWNT/PANI electrode had been characterized by cyclic voltammetry (CV) and galvanostatic charge-discharge technique. The specific capacitance and long cycle life of P-MWNT-PANI electrode material were both much higher than MWNT/PANI. These interesting results indicate that multi-amino dendrimer, PAMAM, covalently linked on MWNT provides more reaction sites for in-situ polymerization of ordered PANI, which could efficiently shorten the ion diffusion length in electrolytes and lead to making fully use of conducting materials.

The complete mitogenome and phylogenetic analysis of Acrossocheilus beijiangensis (osteichthyes: Cyprinidae).

Acorssocheilus beijiangensis is an endemic south China stream-dwelling cyprinid species. Its complete mitochondrial genome is 16,596 bp in length, consisting of 13 protein-coding genes, 22 tRNA genes (ranging from 67 bp in tRNACys to 76 bp in tRNALeu and tRNALys ), two rRNA genes (959 bp in 12S rRNA and 1683 bp in 16S rRNA), and one control region (937 bp). Its overall base composition is A: 31.1%, C: 27.9%, G: 16.2%, and T: 124.8%. The complete mitogenome of the Chinese barred species of Cyprinidae could provide a basic data for further phylogenetics analysis.

Magnesium with micro-arc oxidation coating and polymeric membrane: an in vitro study on microenvironment.

Numerous modification methods have been reported to enhance the corrosion resistance of magnesium with positive results. However, little attention has been paid on their impact on micro-environment, particularly the ion concentration and local pH value. In this study, two different coatings were prepared on magnesium, one with porous micro-arc oxidation (MAO) coating alone, and the other with additional polymer polyhydroxybutyrate (PHB) membrane using spinning technique. Their in vitro corrosional and biological behaviors were investigated and compared. Both coatings were found to reduce the degradation rate of magnesium, but an additionally deposited PHB membrane was superior to MAO-coated magnesium since it could produce a micro-environment with preferable local pH value and ion concentration for osteoblast proliferation. Our study suggests that micro-environment should be another critical issue in evaluation of a modification method for orthopaedic implants.

[Application of amnion membrane transplantation combine with mitomycin C in the treatment of pterygium].

PURPOSE: To evaluate the effect of combining amniotic membrane transplantation with mitomycin C to prevent the recurrence in primary pterygium surgery. METHOD: Forty eyes were simply excised pterygium and were applied with amniotic membrane transplantation with 0.2 mg/ml mitomycin. RESULT: Following up 6 to 18 months, the rate of recurrence is 3%. CONCLUSION: Applying amniotic membrane transplantation with mitomycin in operation can decrease pterygium recurrence, and no serious complication happens.