Search

BACKGROUND: The use of biological materials as cell carriers can provide a 3D culture microenvironment, support cell viability and function, and may expand the number and therapeutic effects of cell therapy. Therefore, it is very important to find a suitable biological material. OBJECTIVE: To prepare injectable gelatin methacryloyl porous microspheres, and explore their biocompatibility and the potential of loaded cells for tissue engineering. METHODS: Injectable gelatin methacryloyl porous microspheres were prepared by microfluidic technology. The microscopic morphology and hardness of microspheres were characterized. MC3T3-E1 cells were cultured in normal medium as control group and microsphere extract as experimental group. Cell proliferation was detected by CCK8 assay. Cell survival was detected by live dead cell staining. Microspheres were co-cultured with CD3+ T cells. CD3+ T cells cultured alone were used as controls. The effect of microspheres on T cell activation was observed under light microscope. The morphology of T cells loaded with microspheres was observed by Dapi staining. Flow cytometry was used to verify whether co-culture with microspheres influenced the ratio of CD4+ T cells to CD8+ T cells. RESULTS AND CONCLUSION: (1) Under the inverted microscope, the microspheres were highly dispersed and uniform in size. The diameter size met the injectable condition. Under scanning electron microscope, the microspheres formed porous structure after freeze-drying, and pores were uniformly distributed. The elastic modulus of the microspheres was (9.76±2.04) kPa. (2) CCK-8 assay and live dead cell staining results demonstrated that the tendency and activity of proliferation of MC3T3-E1 cells cultured in the two media had no difference. (3) Under optical microscope, co-culture with microspheres for 2 days did not cause CD3+ T cell activation, and did not interfere with the activation of CD3+ T cells. CD3+ T cells were distributed on the surface and pores of the microspheres. (4) Flow cytometry results showed that microspheres did not affect the ratio of CD4+ T cells to CD8+ T cells. (5) An injectable gelatin methacryloyl porous microsphere was prepared by microfluidic technology, which has good biocompatibility and does not affect cell. It is a kind of biomaterial with broad application prospect in tissue engineering. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, vertebral augmentation surgery has a good effect on osteoporotic vertebral fracture, but with the increasing number of cases, we have found that some patients still complain of obvious pain after receiving vertebral augmentation surgery. OBJECTIVE: To analyze the multiple factors that affect the poor efficacy after vertebral augmentation surgery of acute symptomatic thoracolumbar osteoporotic compression fracture, and to conduct a multivariate logistic regression analysis of related factors. METHODS: The data of 850 patients who were treated with primary vertebral augmentation in the treatment of vertebral compression fractures in Honghui Hospital, Xi’an Jiaotong University from July 2016 to May 2019 were retrospectively analyzed. According to the visual analogue scale score of low back pain within one month after operation, the curative effect was judged by the score, in which ≥ 4 points were regarded as poor curative effect. A total of 61 patients had poor curative effect (poor curative effect group). The random number table method was used to select 61 patients from 789 patients with satisfactory curative effect as the satisfactory group. The gender, age, body mass index, preoperative bone mineral density T value, operative segment, operation time, surgical path, degree of fracture compression, bone cement injection volume, postoperative bone cement leakage, type of bone cement leakage, postoperative adjacent segment fracture, soft tissue injury, and postoperative bone cement distribution were investigated in both groups. Univariate and multivariate logistic regression analysis was used to explore the risk factors of poor efficacy. This study was approved by the Ethics Committee of Honghui Hospital, Xi’an Jiaotong University (approval No. 202005005). RESULTS AND CONCLUSION: (1) There was no significant difference between the two groups of patients in terms of age, gender, operation time, surgical path, the degree of compression fracture, and injured vertebral segment (P > 0.05). There were statistically significant differences in bone cement leakage, adjacent segment fractures, soft tissue injury, bone cement distribution, bone mineral density T value, and bone cement injection volume (P < 0.05). (2) Binary Logistic regression analysis showed that the poor efficacy of vertebral body enhancement after surgery was significantly correlated with bone cement leakage, adjacent segment fractures, soft tissue injury, bone cement distribution, and bone mineral density T value (P < 0.05). (3) The results of ROC analysis showed that bone mineral density T predicted that the AUC of the poor efficacy after vertebral augmentation was 0.809 (β =0.040, 95%CI=0.729-0.888, P=0.000); the best cutoff value was -3.05; the sensitivity and specificity were 0.721 and 0.836, respectively. (4) These results indicate that bone cement distribution, bone cement leakage, adjacent segment fracture, soft tissue injury, and bone mineral density T value are the risk factors for the poor efficacy after vertebral augmentation in patients with acute symptomatic osteoporotic thoracolumbar vertebral compression fracture. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)