Objective:To construct a novel respiratory syncytial virus (RSV) vaccine based on a recombinant influenza virus vector and evaluate its immune protective effects in mice.Methods:A recombinant H1N1 influenza A virus (IAV) expressing the extracellular domain (Gecto) of RSV A2 G protein was constructed and rescued, named as PR8NAGecto/WSN. After in vitro verification of the Gecto expression and PR8NAGecto/WSN growth kinetics, a single dose of PR8NAGecto/WSN was used to immunize BALB/c mice through intranasal administration to evaluate the efficacy of PR8NAGecto/WSN by assessing humoral (IgG, neutralizing antibody), mucosal (IgA) and cellular immunity (IFN-γ ELISPOT). Four weeks after immunization, the mice were challenged with RSV A2 or RSV B9320 to evaluate the protective effects of PR8NAGecto/WSN by analyzing mouse body weight changes, lung tissue virus titers and pathological changes. Results:A single-dose intranasal immunization with PR8NAGecto/WSN induced robust humoral, mucosal and cellular immunity in mice. Moreover, the mice in the immunized group had lower lung virus loads and mild lung pathological damages following the challenge with RSV A or RSV B subtype as compared with the control group.Conclusions:A single-dose intranasal immunization with PR8NAGecto/WSN induces robust immunity and provide protection against RSV A and B challenges in mice. This study provides new ideas and reference for the development of novel mucosal vaccines against RSV.

OB JECTIVE To study the protective effects of saponins from Gleditsia sinensis on ischemic stroke with phlegm and blood stasis （ISPBS）model rats ，and to explore its mechanism. METHODS Totally 119 rats were randomly divided into normal group （normal saline ），sham operation group （normal saline ），model group （normal saline ），nimodipine group （positive control group ，5 mg/kg），G. sinensis saponin low-dose ，medium-dose and high-dose groups （3.21，6.42 and 12.84 mg/kg），with 17 rats in each group. Except for normal group ，other groups were all given high-fat diet+suture-occluded method to induce ISPBS model. The neurological function score ，water content of brain tissue ，pathological morphology of brain tissue ，the changes of hemorheology indexes （whole blood viscosity ， erythrocyte aggregation index ， Casson-viscosity）， four items of blood lipid [triacylglycerol （TG），total cholesterol （TC），low-density lipoprotein cholesterol （LDL-C），high-density lipoprotein cholesterol（HDL-C）] and inflammatory factors in serum and oxidative stress indexes [malondialdehyde （MDA），nitric oxide （NO），superoxide dismutase （SOD）] in brain tissue were determined or observed in rats. The protein expressions of B lymphocytoma 2（Bcl-2），Bcl-2 associated X protein （Bax）and caspase- 3 in cerebral tissue were also detected. RESULTS Compared with normal group ，the score of nerve function ，5 kinds of serum indexes （TC，TG，LDL-C，TNF-α，IL-1β）， hemorheology indexes ，the contents of MDA and NO and protein expressions of Bax and caspase- 3 in cerebral tissue were all increased significantly in model group （P＜0.01）. The levels of HDL-C and IL- 10 in serum ，SOD activity and protein expression of Bcl- 2 in cerebral tissue were decreased significantly （P＜0.01），and obvious lesions such as nuclear pyknosis and cell membrane fragmentation occurred in brain tissue. Compared with model group ，above indexes of administration groups were improved to different extents ，among which there was statistical significance in above indexes of G. sinensis saponin high-dose group （P＜ 0.01）. CONCLUSIONS Saponin from G. sinensis has a good protective effect on ISPBS model rats. Its mechanism may beassociated with reducing oxidative damage ， reducing the production of pro-inflammatory mediators and resisting neuronal apoptosis.

BACKGROUND: Spine has a variety of morphological structures and complicated adjacent location, so the surgery to treat spinal abnormality is a difficult. Three-dimensional (3D) printing technology can transform 3D digital model into physical model, which has been widely used in the field of medicine, even popularized gradually in spine surgery. OBJECTIVE: To summarize the application and status of 3D printing technology in spine surgery, and to make aprospect. METHODS: The first author retrieved CNKI, Baidu Xueshu, Google Scholar, WanFang and PubMed databases for the articles published from 2010 to 2016 using the keywords of 3D printing technology, spine surgery, navigation template,spine physical model, pedicle screw, individualized implants, clinical teaching in Chinese and English, respectively.Finally 29 eligible literatures were enrolled for further analysis in accordance with the inclusion and exclusion criteria.RESULTS AND CONCLUSION: 3D printing technology has been extensively applied in spine surgery, and shows rapid development in preoperative diagnosis, intraoperative navigation, communication, teaching, graft production, implant customization, bone tissue engineering and other aspects. With the development of society, and medical imaging, 3D printing technology will be more promising in the field of medicine, especially in spine surgery

Objective To investigate the effects of different cyclic tensile strains on the proliferation and expression of bone marrow stromal cells (BMSCs)-cocultured human degenerated anulus fibrosus (AF) cells. Methods AF cells were isolated from a patient with degenerated intervertebral disc degeneration (IVD), which were co-cultured with BMSCs. The solely cultured AF cells were used as control group. The two groups of cells were expanded in monolayer, and cyclically strained for 3 hours, which were applied 0, 5%, 10%, 15%and 20%strains at a frequency of 0.25 Hz using BioDynamic test instrument. A flow cytometry method was used to examine the AF cell proliferation at 24 hours followed the application of cyclic tensile strains. After the total RNA was extracted, real-time PCR technology was used to detect the gene expression of collagenⅠand aggrecan. Results Under the same appropriate stress, the proliferative index (PI), the proportion of cells in the period of DNA synthesis, the expression of collagenⅠand aggrecan were significantly higher in the co-cultured group than those of control group (P<0.05). However, the best mechanical stimulation was different in the two groups. For the AF cells, the peaks of PI, the proportion of cells in the period of S period, the expression of collagenⅠand aggrecan were found in the 10% strain group, while for the co-cultured cells, they were found in the 15% strain group. Conclusion Co-culturing with BMSCs has a positive effect on the proliferation and expression of human degenerative fibrous ring cells, which can protect AF cells from bad stress stimulation.

Objective To study the influence of spinal instability after lamina decompression in symptoms and progno?sis. Methods The 76 patients were followed up for a minimum of 4 more years. The patients were divided into instability group (n=27) and non-instability (n=49) group according to the X-ray result of the final follow-up. The visual analogue scale (VAS) score, JOA score and improvement rate were compared between two groups at preoperation, 3-month after operation and the final follow-up. Results There were no significant differences in gender, age and mean follow-up time between two groups. There were no significant differences in VAS and JOA scores before surgery, 3-month after surgery and final follow-up between two groups. Postoperative VAS score decreased and JOA score increased with the increase in follow-up time (P<0.05). There were no significant differences in improvement rate [(80.0±8.8)%vs (83.6±11.7)%] and improvement ratio [81.48%(22/27) vs 61.22%(30/49)] between two groups (P > 0.05). Conclusion Although some patients show instability even with lumbar spondylolisthesis after lamina decompression on radiograph,which is no correlation with improvement of symptoms. With appropriate indications, lamina decompression is a simple and effective surgical method,which also retains the spinal movement function.

Intramedullary signal intensity (ISI) changes in morphology and extent of T2-weighted (T2W) in preopera?tive cervical magnetic resonance (MR) images was thought to be indicative to the prognosis of cervical spondylotic myelopa?thy (CSM) in recent years. However, the significance of ISI changes in predicting CSM prognosis remains controversial. Lack of satisfied evaluating approch of ISI on magnetic resonance imaging (MRI) is the main drawback. Identification of the type of T2WI ISI on preoperative MR imaging could give important information in predicting surgical outcome of patients with CSM. Currently, consensus is reached that preoperative multi-segmental T2WI ISI or sharp T2WI ISI indicate a worse prognosis for patients with CSM compared with regression of T2WI ISI. The literatures that link magnetic resonance imaging signal changes with prognosis of surgery to correct cervical spondylotic myelopathy are reviewed. The correlation of pathological changes and radiological performance of intramedullary signal intensity with prognosis of CSM are summarized to understand the significance of T2WI ISI on prognosis of surgical outcome.

Objective To observe changes in bone mass and symptom duration in patients with lumbar disc herniation(LDH) and explore the relationship between osteoporosis and clinical features of LDH. Methods 83 LDH patients undergoing surgery were enrolled in the study from November 2008 to September 2009. Before surgery, dual-energy X-ray absorptiometry was used to detect bone mineral density of lumbar spine and hip, and calculate T score. The patients were divided into three groups according to the T score: group A (normal bone mass group, n=27), group B (osteopenia group, n=31) and group C (osteoporosis group, n=25). The differences in the duration of symptoms and pathological types were compared between the groups. The relationship between BMI and lumbar spine T-score was explored. Results There were no significant differences in the pathological types among the three groups. The symptom duration in group C was significantly shorter than in group A (P < 0.05). There was no correlation between BMI and lumbar spine T-score (r=0.20, P=0.070). There was positive correlation between BMI and Hip T-score (r=0.263, P=0.016). Conclusion Osteoporosis may affect the symptom duration of LDH patients. We should attach great importance to patients with osteoporosis and LDH.

Objective To evaluate and compare the presence of the nerve root sedimentation sign in patients with lumbar spondylolisthesis (LS) and lumbar disc herniation(LDH). Methods One hundred and fifty-one patients with degen?erative lumbar spinal disease treated by surgery from July 2012 to March 2014 were reviewed retrospectively in Tianjin Hos?pital. All the patients were divided into two groups:LS group (48 cases) and LDH group (103 cases). The clinical outcomes were evaluated by Japanese Orthopedic Association (JOA). The probability of positive sedimentation sign was compared be?tween LS group and LDH group. Correlation between the JOA score and nerve root sedimentation sign were analysed in two groups. Results There was no statistical difference in JOA score between LS group and LDH group (15.83±3.57 vs 16.76± 3.10, t=1.624, P=0.107). A positive sedimentation sign was identified in 39 patients in the LS group (81.25%) but in 65 pa?tients in the LDH group (63.11%). The difference between LS group and LDH group was statistically significant(χ2=5.028, P=0.031). In LS group, JOA scores of patients with positive nerve root sedimentation sign were lower than those of patients with negative nerve root sedimentation sign(15.33±3.50 vs 18.00±3.20, t=2.092,P=0.042);but in LDH group, there was no statistical difference in JOA scores of patients between positive nerve root sedimentation sign and negative nerve root sedi?mentation sign (16.40±3.13 vs 17.37±2.99, t=1.539, P=0.127). Conclusion A positive sedimentation sign also occurs in pa?tients with LDH, but positive nerve root sedimentation sign are more likely to appear in patients with lumbar spondylolisthe?sis who have worse clinical symptoms.

10.3969/j.issn.2095-4344.2013.24.017

Objective To analyze the clinical results and early complications of corpectomy and reconstruction with titanium mesh cage implantation and pedicle screw fixation via a single posterior approach for severe thoracic and lumbar fractures.Methods Forty-four patients treated by reconstruction with titanium mesh cage implantation and pedicle screw fixation via a single posterior were studied retrospectively.There were 35 males and 9 females,with an average age of 37.3 years(range,19-66 years).The injury segments include 1 case at T11,5 cases at T12,20 cases at L1,11 cases at L2,5 cases at L3 and 2 cases at L4.According to AO classification,there were 24 cases of A3,17 cases of B1 and B2,and 3 cases of C1.According to ASIA,there were 10 cases of grade A,17 cases of grade B,10 cases of grade C and 7 cases of grade D.The neurologic function and effectiveness of correction of preoperative,immediate postoperative and 2years follow-up were compared,and the clinical outcome and early complications were analyzed.Results The follow-up time was 24 to 58 months,mean 38.9 months.At the time of 2 years postoperation,43 cases of incomplete neurologic deficit had improved 1 or 2 ASIA grades except 1 case of grade A.The results of decompression and reduction were satisfactory from the postoperative radiographic examinations.The correction maintained well and the implant loosening was not seen in 43 cases(97.7%)at the last follow-up.The com plications include:excessive blood loss(＞1500 ml)in 9 cases,transient nerve root injury in 4,cerebrospinal fluid leakage in 3,instrumentation failure in 1,mesh cage malposition in 3,iatrogenic leaving of free bone granula into the canal in 2,and superficial infection in 1.Conclusion This technique is effective for decompression and fusion,less invasive than combined anteroposterior procedure,and may be another good alternative for the treatment of severe thoracic and lumbar fractures.The early complications are not rare,but most of them are not serious and are relative to techniques.