Objective To explore the relationship between lumbar disc degeneration (LDD) of lumbar spinal stenosis(LSS)and the dural sac cross-sectional area(DSCA)by MRI measurement. Methods 91 patients with central degenerative LSS were randomly selected and 91 age-and sex-matched people without LSS were select-ed as a control group. LDD was classified into five grades by MRI detection according to the method proposed by Pfirrmann and DSCA were measured. Results LDD was not associated with age in LSS. The proportion of severe degenerated disc in lower lumbar levels were higher than that of L2/3 in the two groups;DSCA in severe degenerat-ed disc group was significantly smaller than that in light degenerated group only in L2/3 and L3/4 in LSS. There were no statistical differences in every lumbar level in the control group. Conclusions LDD in L4/5 and L5/S1 of LSS is more severe than that of the normal people. DSCA and LDD are positively correlated in L2/3 and L3/4,but not in L4/5 and L5/S1 for LSS.

BACKGROUND:Hydrogel microparticles,due to their porous and injectable properties,have demonstrated unique advantages in biomedical fields,such as the delivery of cells and bioactive factors/drugs,the construction of tissue repair scaffolds.They have broad application prospects. OBJECTIVE:To review the latest research progress and discuss the key problems and challenges in the research of bone tissue engineering based on hydrogel microparticles. METHODS:The relevant articles in PubMed and CNKI were searched by computer.The English key words were"hydrogels,microparticles,microspheres,microcarriers,bone,bone defect,bone repair,bone healing,bone tissue engineering"while the Chinese key words were"hydrogels,microparticles,microspheres,bone tissue engineering,bone defect,bone repair,bone regeneration".The retrieval period was from 2002 to 2022,and 127 articles were finally included for review. RESULTS AND CONCLUSION:(1)At present,various hydrogel microparticles have been developed for use in bone tissue engineering strategies,for example,hydrogel microparticles carrying cells or bioactive factors/drugs,hydrogel microparticles as biological scaffolds,stimulus-responsive hydrogel microparticles,biomineralized hydrogel microparticles,hydrogel microparticles combined with other biological materials.(2)Bone tissue engineering repair strategies based on hydrogel microparticles mainly regulate bone repair by promoting stem cell recruitment and osteogenic differentiation,regulating the local inflammatory microenvironment and promoting angiogenesis at the site of injury.However,the present studies did not deeply explore the effect of bone tissue engineering based on hydrogel microparticles on the recruitment and differentiation of endogenous stem cells and the regulation of the inflammatory microenvironment by the physical and chemical properties of hydrogel microparticles.The long-term in vivo adverse reactions of hydrogel microparticles have not been explored yet,and it is difficult to mass-produce them,thus future research needs to strengthen the mechanism exploration and technical route,so as to provide a reasonable reference for the development of hydrogel microparticles that can be used for clinical transformation.

OBJECTIVE：To stud y the effects of sinapine thiocyanate （ST） on the proliferation ，epithelial mesenchymal transformation（EMT）and metastasis of human cutaneous squamous cell carcinoma SCL- 1 cells，and to investigate its possible mechanism. METHODS ：Human cutaneous squamous cell carcinoma SCL- 1 cells were divided into blank control group （0.1％ DMSO） and ST different concentration groups （5，10，20 μmol/L）. CCK- 8 assay，5-ethynyl-2′-deoxyuridine（EDU）test， scratch test and Transwell chamber invasion test were adopted to test the proliferation ，migration and invasion ability. The expression of N-cadherin and E-cadherin were detected by Western blot and immunofluorescence assay . Other SCL- 1 cells were collected and divided into blank control group （0.1％ DMSO），ST group （20 μmol/L），ST+NSC228155 group [ 20 μmol/L ST+100 μmol/L NSC228155（EGFR agonist ）] and ST+SC 79 group [ 20 μmol/L ST+20 μmol/L SC79（PI3K/Akt agonist ）]. The proliferation ，migration and invasion ability of SCL- 1 cells in each group were detected by CCK- 8 assay，scratch test and Transwell chamber invasion assay. The expression of epidermal growth factor receptor （EGFR），phosphatidylinositol 3 kinase（PI3K），phosphorylated phosphatidylinositol 3 kinase（p-PI3k），protein kinase B （Akt）and phosphorylated protein Akt （p-Akt）protein of cells in blank control group and ST different concentration groups（5，10，20 μmol/L）were determined by Western blot assay so as to validate the relationship between ST effect and EGFR/ PI3K/Akt signaling pathway. SCL- 1 cells and human normal skin fibroblasts cell WS 1 were divided into blank control group （0.1％ DMSO），ST group （20 μmol//L），ZD1839 group（positive control ，20 μmol//L，EGFR inhibitor ）and LY 294002 group（positive control，20 μmol//L，PI3K/Akt inhibitor ）. CCK- 8 assay was used to detect the cell proliferation in order to evaluate the cells cytotoxicity of ST. RESULTS ：Compared with blank control group ，the proliferation ，migration and invasion ability of SCL- 1 cells were significantly decreased in 5，10，20 μmol/L ST groups（P＜0.05）. Western blot and immunofluorescence assay showed that the expression of N-cadherin in SCL- 1 cells were decreased significantly in 5，10，20 μmol/L ST groups（P＜0.05），while the protein expression of E-cadherin was increased significantly （P＜0.05）；the protein expressions of EGFR ，p-PI3K and p-Akt were significantly decreased （P＜0.05）. Compared with ST group ，the proliferation ，migration and invasion ability of SCL- 1 cells were increased significantly in ST + NSC 228155 group and ST + SC 79 group （P＜0.05）. Compared with blank control group ，the proliferation ability of WS 1 cells had no significant change in ST group ，while the proliferation ability of SCL- 1 cells was decreased significantly （P＜0.05）；the proliferation ability of the two kinds of cells were decreased significantly in ZD 1839 group and LY 294002 group（P＜0.05）. Compared with ST group ，the proliferation ability of WS 1 cells was decreased significantly in ZD1839 group and LY 294002 group（P＜0.05），but there was no significant difference in the proliferation ability of SCL- 1 cells （P＞0.05）. CONCLUSIONS ：ST may inhibit the proliferation ，EMT and metastasis of SCL- 1 cells through inhibiting the activation of EGFR/PI 3K/Akt signaling pathway ，and its side effects are few.