In the field of nerve repair,one major challenge is the formation of neuroma.However,reports on both the promotion of nerve regeneration and prevention of traumatic neuroma in the clinical settings are rare in the field of nerve repair.One of the reasons could be the insufficiency in the follow-up system.We have conducted 33 cases of nerve repair using PRGD/PDLLA/b-TCP conduit without any sign of adverse reaction,especially no neuroma formation.Among them,we have selected two cases as representatives to report in this article.The first case was a patient with an upper limb nerve wound was bridged by PRGD/PDLLA/b-TCP conduit and a plate fixation was given.After nearly 3-years’follow-up,the examination results demonstrated that nerve regeneration effect was very good.When the reoperation was performed to remove the steel plate we observed a uniform structure of the regenerated nerve without the formation of neuroma,and to our delight,the implanted conduit was completely degraded 23 months after the implantation.The second case had an obsolete nerve injury with neuroma formation.After removal of the neuroma,the nerve was bridged by PRGD/PDLLA/b-TCP conduit.Follow-up examinations showed that the structure and functional recovery were improved gradually in the 10-month follow-up;no end-enlargement and any other abnormal reaction associated with the characteristic of neuroma were found.Based on our 33-case studies,we have concluded that PRGD/PDLLA/b-TCP nerve conduit could both promote nerve regeneration and prevent neuroma formation;therefore,it is a good alternative for peripheral nerve repair.
Yixia YinBinbin LiQiongjiao YanHonglian DaiXinyu WangJifeng HuangShipu Li
To gain a better understanding of the anticancer effects of hydroxyapatite （HAP） nanoparticles in vivo and in vitro, the effects of the interaction of HAP nanoparticles with hepatoma cells were explored. HAP nanoparticles were prepared by homogeneous precipitation and characterized by laser particle analysis and transmission electron microscopy （TEM）. HAP nanoparticles were observed to be uniformly distributed, with rod-like shapes and diameters in the range of 42.1-87.1 nm. Overnight attached, suspended, and proliferating Bel-7402 cells were incubated with HAP nanoparticles. Inverted microscopy observation revealed that HAP nanoparticles with a cell membrane showed good adsorption. TEM demonstrated that HAP nanoparticles were present on the surface of cells, continuously taken up by cells through endocytosis, and transported in vesicles close to the nucleus. Fluorescence microscopy showed that the concentrations of intracellular Ca2＋ labeled with Fluo-3 calcium fluorescent probe were significantly enhanced. In addition, inverted microscopy observation revealed that suspended cells treated with HAP nanoparticles did not adhere to the culture bottle, resulting in cell death. After the overnight attached cells were treated with HAP nanoparticles for 96 h with increasing doses of HAP nanoparticles, inverted microscopy observation revealed that cell proliferation was slowed and ceU-ceU adhesion was weakened. Feulgen staining and image analysis indicated that the nuclear DNA content of the cells was markedly reduced, and argyrophilic nucleolar organizer region （AgNOR） staining and image analysis indicated that the number of AgNORs was significantly decreased. Therefore, hepatoma cells brought about the adsorption, uptake, transport and degradation of HAP nanoparticles. In addition, HAP nanoparticles affected hepatoma cells with regard to cell-cell adhesion, cell and extracellular matrix adhesion, and DNA and protein synthesis; thus inhibiting cell proliferation. This understanding of the effects of inter
