Potential use of 3D-printed graphene oxide scaffold for construction of the cartilage layer.

BACKGROUND: Three-dimensional (3D) printing involves the layering of seed cells, biologically compatible scaffolds, and biological activity factors to precisely recapitulate a biological tissue. Graphene oxide (GO), a type of micro material, has been utilized as a small molecule-transport vehicle. With the proliferation of GO, the biocompatibility of chondrocytes in a microenvironment constructed by 3D printed scaffolds and GO is innovative. Accordingly, we speculate that, as a type of micro material, GO can be used with 3D scaffolds for a uniform distribution in the cartilage layer. RESULTS: A qualitative analysis of the chondrocyte-proliferation potential revealed that the culture of 3D printing with a 10% GO scaffold was higher than that of the other groups. Meanwhile, the progress of cell apoptosis was activated. Through scanning electron microscopy, immunofluorescence, and in vivo research, we observed that the newborn cartilage matrix extended along the border of the cartilage and scaffold and matured. After an analysis with immunohistochemical staining with aggrecan and collagen I, the cartilage following the 3D-printed scaffold was thinner than that of the 3D-printed GO scaffold. Furthermore, the collagen I of the cartilage expression in treatment with the GO scaffold was significant from week 2 to 6. CONCLUSIONS: The findings indicate that a 3D-printed GO scaffold can potentially be utilized for the construction of a cartilage matrix. However, the optimum concentration of GO requires further research and discussion.

3D printing hydrogel with graphene oxide is functional in cartilage protection by influencing the signal pathway of Rank/Rankl/OPG.

3Dprinting is defined as the use of printing technology to deposit living cells, and biomaterials on a given /a substrate. Graphene oxide nanoparticles (GO-np) have been used as a delivery vehicle for small molecule drugs in order to investigate the state of GO-np within 3D tissue constructs in terms of a composite 3D printing scaffold, which in turn is relevant to the protection of cartilage. We transplanted rats with hydrogel/GO-np and hydrogel, which in turn showed that hydrogel/GO-np protected the tissue of cartilage by the signal pathway of Rank/Rankl/OPG. Those findings indicated that GO-np may be potentially used to control the release of carrier materials and influence the signal pathway of Rank/Rankl/OPG.

Effect of down-regulation of voltage-gated sodium channel Nav1.7 on activation of astrocytes and microglia in DRG in rats with cancer pain

Objective:To evaluate the effect of down-regulation of Nav1.7 on the activation of astrocytes and microglia in DRG of rats with cancer pain, and explore the transmission of the nociceptive information.Methods:Lentiviral vector harboring RNAi sequence targeting theNav1.7gene was constructed, and Walker 256 breast cancer cell and morphine was injected to build the bone cancer pain model and morphine tolerance model in rats. Lentiviral vector was injected. Rats in each model were divided into 4 groups: model group, PBS group, vehicle group and LV-Nav1.7 group. The expression levels of GFAP and OX42 in dorsal root ganglia (DRG) were measured.Results: After the animal model was built,the level of Nav1.7, GFAP and OX42 was improved obviously with the time prolonged, which was statistically significant (P<0.05). The expression level of GFAP and OX42 in the DRG in the LV-Nav1.7 group declined obviously compared to the model group, PBS group and vehicle group (P<0.05).Conclusions:Intrathecal injection of Navl.7 shRNA lentiviral vector can reduce the expression of Nav1.7 and inhibit the activation of astrocytes and microglia in DRG. The effort is also effective in morphine tolerance bone cancer pain model rats.

Epidemiological features of 877 cases with hip fraction / 中华流行病学杂志

Objective To analyze the epidemiological features of hip fraction,and to improve the intervention program on this disease.Methods To investigate the clinical data of the patients with hip fraction who were treated at local hospitals,from Jan.to Dec.,2012.Information regarding sex,age,site and cause of the fracture was analyzed.Results 877 cases were treated at the local hospitals; including 516 males (58.84％) and 361 females (41.16％).The overall incidence of hip fraction was 10.0/100 000,with 11.2/100 000 in males and 8.8/100 000 in females.The incidence was higher in males than that in females (x2=4.281,P=0.033).Age distribution of the patients was:344 cases in age 71-82 (39.22％),196 cases in age 61-70 (22.35％) and 185 cases in age 51-60 (21.09％).Transcervical fracture appeared more than intertrochanter fracture of femur (x2=21.423,P＜0.001),with males more than females in both fractures on femur (x2=12.816,P＜0.001 ; x2=13.773,P＜0.001).The top 3 factors causing hip fractions would contain tumble (64.88％),falling (20.07％) and traffic accident (10.49％).Conclusion Incidence of hip fraction would increase with age with tumble as the major cause to it.