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Objective@#To understand health literacy and its associated factors among middle school students in Shenzhen, to provide scientific basis for further formulating targeted intervention measures.@*Methods@#From October to December, 2019, 7 423 middle school students in 10 districts of Shenzhen were selected by multistage stratified random cluster sampling. Multivariate linear regression was used to analyze factors affecting health literacy and scores in each dimensions.@*Results@#The total score for health literacy was(107.39±22.31), including physical activity(16.81±5.28), interpersonal relationship(20.69±4.10), stress management(21.64±5.53), spiritual growth(14.93±3.96), health awareness (15.61±4.96) and nutrition(17.71±4.65). According to the multivariate linear regression analysis, girls, general and vocational high schools, educational level of parents and boarding in school were significantly associated with health literacy of middle school students( B=-3.04, -7.72, -9.99, 1.56, 2.78, -3.85, P < 0.05 ).@*Conclusion@#Middle school students in Shenzhen have a high level of health literacy, which is related to school type and parental educational background. It is suggested that measures should be taken to improve the health literacy of middle school students.
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BACKGROUND:Articular cartilage is a highly diferentiated tissue, which is very limited in its ability to repair after injury. Stem cel therapy for cartilage repair has completely solved this problem. OBJECTIVE: To investigate the mechanism that diferent growth factors induce the diferentiation of bone marrow mesenchymal stem cels into chondrocytes. METHODS:Passage 5 rat bone marrow mesenchymal stem cels were induced by diferent growth factors and their combinations, including transforming growth factor beta 1 (TGF-β1) group, TGF-β1+insulin growth factor-1 (IGF-1) group, and bone morphogenetic protein 2 (BMP-2)+IGF-1 group, TGF-β1+BMP-2 group, TGF-β1+IGF-1+ BMP-2 group, and blank control group. At 21 days of induction, cels were stained with alcian blue and alizarin red; RT-PCR was employed to detect colagen I mRNA expression. RESULTS AND CONCLUSION:Alcian blue staining showed metachromasia in the cytoplasm and mesenchyma, and proteoglycan was expressed green; alizarin red staining showed no orange calcium nodules. The bone marrow mesenchymal stem cels were preliminarily deduced to diferentiate into chondrocytes, but could not express the cel phenotypes of bone cels. In the blank control group, the expression of colagen I mRNA was negative. Compared with the TGF-β1 group, the mRNA expression of colagen I was lower in the BMP-2+IGF-1 group, but higher in the TGF-β1+BMP-2 group and TGF-β1+IGF-1+BMP-2 group (P < 0.05). Moreover, the expression of colagen I mRNA was highest in the TGF-β1+IGF-1+BMP-2 group (P < 0.05). These findings indicate that TGF-β1 alone is able to induce the chondrogenic diferentiation of bone marrow mesenchymal stem cels, and the combination of TGF-β1, IGF-1 and BMP-2 can play the biggest role to induce the chondrogenic diferentiation of bone marrow mesenchymal stem cels.
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BACKGROUND:Nano bone putty and bone cement injection are two common methods to strengthen the fixation of pedicle screws, but there are relatively few reports on the comparison of their strengthening effects. OBJECTIVE:To compare the biomechanical characteristics of bone cement and nano bone putty strengthening pedicle screw implantation in the fixation of osteoporotic vertebral body. METHODS: Totaly 24 human cadaveric pedicles were obtained, which were al in line with osteoporosis standards, and randomly divided into 3 groups: control group (only implanted pedicle screws), bone cement group (first injected bone cement in the nail channel, and then implanted pedicle screws) and nano bone putty group (first injected nano bone putty in the nail channel, and then implanted pedicle screws). After 2 hours of implantation, the maximum axial pulout strength and the maximum rotation torque of specimens in each group were determined. RESULTS AND CONCLUSION:The maximum axial pulout strength and maximum rotation torque of the bone cement and the nano bone putty groups were greater than those of the control group (P < 0.05), and the maximum axial pulout strength and the maximum rotation torque of the bone cement group were greater than those of the nano bone putty group (P < 0.05). These results demonstrate that the maximum axial pulout strength and the maximum rotation torque of pedicle screw implantation in the fixation of osteoporotic vertebral body can be effectively improved by injection of bone cement and nano bone putty, and the strengthening effect of bone cement is more obvious.
