Combined pedicle subtraction osteotomy and polysegmental closing wedge osteotomy for correction of the severe thoracolumbar kyphotic deformity in ankylosing spondylitis / 中华外科杂志

<p><b>OBJECTIVE</b>To study retrospectively the efficacy and complications of combined pedicle subtraction osteotomy (PSO) and polysegmental closing wedge osteotomy for correction of the severe rigid thoracolumbar kyphotic deformity in ankylosing spondylitis (AS).</p><p><b>METHODS</b>A total of 8 consecutive male patients with AS and severe thoracolumbar kyphotic deformity (mean age 32 years, range 28 - 46) were involved in this study from August 2004 to June 2007. The average preoperative Cobb angle of thoracic spine (T(1)-T(12)) was 96 degrees (range, 80 degrees - 112 degrees ), the mean preoperative angle of lumbar lordosis (L(1)-S(1)) was 10 degrees (5 degrees - 15 degrees ). The mean chin-brow angle was 47 degrees (range, 40 degrees - 58 degrees ). The average gaze angle was 43 degrees (range, 32 degrees - 50 degrees ). After preoperative assessment, single-level PSO was performed in L(3) vertebrae and two-level polysegmental closing wedge osteotomy was performed in thoracolumbar vertebrae (T(12)-L(1), L(1-2)). Radiographic and clinical results and complications were assessed.</p><p><b>RESULTS</b>The surgical time was (298.1 +/- 20.7) minutes and blood loss during the procedure was (1588.8 +/- 171.6) ml. The follow-up period was (11.5 +/- 7.7) months. The postoperative angle and the amount of correction of the thoracic and lumbar spine were 76.1 degrees +/- 9.6 degrees , 20.3 degrees +/- 1.1 degrees and 48.4 degrees +/- 4.7 degrees , 38.4 degrees +/- 4.7 degrees respectively. The postoperative chin-brow and gaze angle was 16.5 degrees +/- 4.6 degrees and 73.0 degrees +/- 5.2 degrees , respectively. The amount of correction for sagittal balance was (12.3 +/- 1.6) cm. No nerve, vascular injury, stress fracture and coronal decompensation occurred in the patients.</p><p><b>CONCLUSIONS</b>Combined PSO and polysegmental closing wedge osteotomy by posterior approach only is safe and effective for correction of the severe rigid thoracolumbar kyphotic deformity in AS. The visual field is significantly improved after surgery.</p>

Transfer and Expression of Recombinant Human Thrombopoietin Gene in COS-7 Cells and Mice In Vivo / 中国实验血液学杂志

In order to investigate the expression of recombinant TPO gene in COS-7 cells and in vivo of the mouse model, eukaryotic expressing plasmid pcd2/TPO with human TPO cDNA was constructed with DNA recombinant techniques. The plasmid pcd2/TPO was transiently transfected into the COS-7 cells by means of lipofection, the naked pcd2/TPO plasmid was injected into the skeletal muscle of mice with electric pulses. RT-PCR and ELISA methods were used to detect the TPO expression of the transfected COS-7 cells, both showed high level expression. The MTT test showed the expressed TPO had proliferative activity to TPO-dependent cell line. High efficiency of gene transfer in transgenic mice was also observed by RT-PCR and immunohistochemical methods. The serum TPO level [(1 185 +/- 264) ng/L] in transgenic mice was quite different compared with the normal mice [(250 +/- 76) ng/L]. All these results provided solid foundations for the research of TPO gene therapy in the future.