ABSTRACT
Objective To investigate the effect of bone morphogenetic protein 2 (BMP2)on ossification of the posterior longitudinal ligament (OPLL) and its relationship with transforming growth factor-3 (TGF-3)/Smad signaling pathway.Methods The expression vectors of wild type pcDNA3.1-BMP2 (WT),mutant pcDNA3.1-BMP2 (37G),mutant pcDNA3.1-BMP2 (190T) and mutant pcDNA3.1-BMP2 (37G/190T) were constructed and identified by agarose gel electrophoresis.The constructed vector was transfected into mouse embryonic fibroblasts C3H10T1/2 mediated by liposome to detect the expression of BMP2.Six groups were divided according to the transfection situation:(1) the non-transfection group;(2) empty vector pcDNA3.1 transfection group;(3) pcDNA3.1-bmp2 (WT)transfection group;(4) pcDNA3.1-bmp2 (37G) transfection group;(5) pcDNA3.1-bmp2 (190T)transfection group;(6) pcDNA3.1-bmp2 (37G/190T) transfection group.The experimental and control group were defined according to whether BMP2 polymorphism was included.Therefore,the nontransfection group and empty vector pcDNA3.1 transfection group were control groups,and the other groups were experimental groups.The expression of phosphorylated Smad1/5/8 and Smad4 in positive cell clones were detected by western blotting,and the alkaline phosphatase (ALP) was detected by quantitative detection kits.The protein expressions were compared among the experimental groups.Results Two fragments digested from pcDNA3.1-BMP2 represented 1.2 kb and 5.4 kb by agarose electrophoresis.The direct sequencing results were in accordance with target gene sequence.BMP2 gene was successfully transfected and stably expressed in C3H10T1/2 cells.Western blotting showed that the expression of phosphorylated Smad1/5/8 protein in the experimental groups was increased significantly after transfection,with significant difference between the experimental groups and the control groups (P ＜0.05),but without significant differences among the experimental groups (P ＞ 0.05).The expressions of Smad4 protein transfected by wild or mutation type pcDNA3.1-BMP2 were significantly higher than those in the control groups (P ＜ 0.05),and the expressions of Smad4 protein transfected by pcDNA3.1-BMP2(37G) and pcDNA3.1-BMP2 (37G/190T) were significantly higher than those in the other experimental groups (P＜0.05).The ALP activity results of experimental groups transfected by pcDNA3.1-BMP2 (37G) and pcDNA3.1-BMP2 (37 G/190T) were (30.56 ± 0.46) nmol · min-1 ·mg-1 and (29.62 ±0.68)nmol · min-1 · mg-1,with no significant difference between the two groups (P ＞0.05).However,there were significant differences between the two groups and other experimental groups (P ＜0.05).The Ser37Ala (T/G) polymorphism in exon 2 of BMP2 gene was positively correlated with ALP activity in stably transfected C3H10T1/2 cells.Conclusion The Ser37Ma (T/G) polymorphism in exon 2 of BMP2 gene promotes OPLL ossification through TGF-β/Smad signaling pathway,the possible mechanism for which is to up-regulate the protein expressions of Smad4 and ALP.
ABSTRACT
BACKGROUND:It is controversial whether anterior approach alone, or combined anterior and posterior approaches were used for high level and multiple segments of severe ossification of cervical posterior longitudinal ligament. OBJECTIVE:To explore the difference of anterior approach versus combined anterior and posterior approaches for the treatment of high level and multiple segments of severe ossification of cervical posterior longitudinal ligament. METHODS:A total of 21 cases of high level and multiple segments of severe ossification of cervical posterior longitudinal ligament were included in this study. There were 9 males, aged 56-72 years, and 12 females, aged 58-70 years. We used anterior decompression and titanium mesh bone graft fusion in 11 cases which lesion located between C2-5 vertebra, and ossification excision, combined anterior (titanium mesh plate and screw) and posterior (lateral mass screw) approaches in 10 cases which between C3-7 vertebra. Japanese Orthopaedic Association score system was used to evaluate the results. The excellent and good rate and improvement rate were calculated. RESULTS AND CONCLUSION:The excellent and good rate was 90%and improvement rate was 82%in 10 cases using combined anterior and posterior approaches. The excellent and good rate was 73%and improvement rate was 73%in 11 cases using anterior treatment alone. Significant differences in the excellent and good rate and improvement rate were detected between the two groups (P<0.05). These suggested that combined anterior and posterior approaches for high level and multiple segments of severe ossification of cervical posterior longitudinal ligament is a better operative procedure.
ABSTRACT
BACKGROUND:Cervical expansive unilateral open-door laminoplasty has obtained definite curative effects in treatment of cervical spondylosis in the clinic. OBJECTIVE:To summarize the effects of cervical expansive unilateral open-door laminoplasty for cervical spondylosis from the evolution of surgeries, the advantages and disadvantages of each surgery and postoperative complications. METHODS:Unilateral open-door, expansive laminoplasty, indications, and postoperative complications were key words. Computer was used to search VIP journal ful-text database and PubMed database, and 65 articles were used for further analysis. RESULTS AND CONCLUSION:Cervical expansive unilateral open-door laminoplasty for multi-segmental cervical spondylotic myelopathy, ossification of posterior longitudinal ligament and spinal cord injury without radiographic spinal fracture and dislocation combined with spinal stenosis had obtained affirmative outcomes. Clinicians should careful y select operation mode and be conscious to prevent postoperative complications.