Does cervical disc arthroplasty have lower incidence of dysphagia than anterior cervical discectomy and fusion? A meta-analysis.

OBJECTIVE: Dysphagia is a common occurrence after anterior cervical spine surgery. The aim of this meta-analysis was to evaluate the incidence of dysphagia after ervical disc arthroplasty (CDA) compared with anterior cervical discectomy and fusion (ACDF). MATERIAL AND METHODS: The electronic databases, including PubMed, EMBASE and Cochrane Central Register of Controlled Trials, were searched to identify the randomized controlled trials comparing CDA with ACDF. Studies were included only if the incidence of postoperative dysphagia was investigated. Study selection, "risk of bias" assessment, and data extraction were independently performed by two investigators. Data analyses were conducted with RevMan 5.3 software. RESULTS: Ten studies involving 2711 patients (CDA group, n=1512; ACDF group, n=1199) were identified. All studies were determined to have a low risk of bias. Pooling analysis of these studies showed that the incidence of dysphagia was 9.46% (143/1512) after CDA versus 12.09% (145/1199) after ACDF. Meta-analysis showed the statistical difference between two groups with regards to the incidence of dysphagia (risk ratio 0.76; 95% confidence interval [0.61, 0.94]; P=0.01). CONCLUSION: This meta-analysis indicates that patients have a significantly lower incidence of dysphagia after CDA than after ACDF. Additional studies are needed.

Deproteinized bone with VEGF gene transfer to facilitate the repair of early avascular necrosis of femoral head of rabbit.

OBJECTIVE: To explore a new method for early avascular necrosis of femoral head (AVNFH) therapy. METHODS: Sixty-nine AVNFH New Zealand adult rabbits were randomly divided into three groups with equal number. In Group A, deproteinized bone (DPB) that absorbed with recombinant plasmid pcDNA3.1-hVEGF165 was implanted into the drilled tunnel of necrotic femoral head. In Group B, only DPB was implanted. In Group C, only tunnel was drilled without DPB or plasmid implanted. Femoral head specimens were obtained at postoperative 1, 2, 4, 8, 16 weeks. The expression of VEGF165 and collagen I was detected by immunohistochemistry. Bone formation was detected generally by X-ray. Angiogenesis and the repair of the femoral head were observed histologically. RESULTS: The expression of VEGF 165 could be detected 2 weeks after implantation in Group A, but it was not observed in other groups. The result of collagen I expression had a significantly difference 2, 4 and 8 weeks after operation in Group A from those in other groups (P < 0.01). X-ray results indicated that there was more bone formation in Group A than in other groups. The regenerated capillary vessels staining result of necrotic femoral head in Group A was significantly different from those in other groups at postoperative 2 and 4 weeks (P < 0.01). CONCLUSIONS: Transfection of hVEGF165 gene enhances local angiogenesis and DPB-VEGF compound improves the repair of necrotic femoral head. Deproteinized bone grafting with VEGF gene transfer provides a potential method for the treatment of osteonecrosis.

Transepithelial transport of Cerulenin across Caco-2 cell monolayers.

The transepithelial transport of Cerulenin across Caco-2 cell monolayers was examined in this study. The permeated amounts of Cerulenin were measured by HPLC method to calculate the permeation rate and the apparent permeability coefficient (P(app)). The transport of Cerulenin was independent on apical pH and exhibited concentration-dependent and nonsatuable even at 10 mM Cerulenin. The permeation rate at 1 mM Cerulenin in the apical-to-basolateral direction was 0.151 ng/min/mg of protein and the P(app) was 3.76 x 10(-6) cm/second. The permeation rate of Cerulenin was affected by neither metabolic inhibitors nor inhibitors for P-glycoprotein, as was the same case in monolayers treated with cytochalasin D. All these data from experiments indicated that transport of Cerulenin across Caco-2 cell monolayers was not mediated by ATP-dependent transport systems nor via paracellular pathway, but via passive diffusion without efflux by P-glycoprotein.