Di Mascio V.,Polytechnic of Milan |
Bellini C.M.,Istituto Ortopedico Galeazzi |
Galbusera F.,Istituto Ortopedico Galeazzi |
Raimondi M.T.,Polytechnic of Milan |
And 3 more authors.
Journal of Applied Biomaterials and Biomechanics | Year: 2010
Aim: The aim of this study was to evaluate the biomechanical effects of the Maverick® disc prosthesis at the implanted and adjacent level by the finite element (FE) method. Materials and Methods: A 3D FE model of the L3-L5 segment was built. To simulate the different physiological movements (flexion, extension, lateral bending, axial rotation) pure moments of 10 Nm were applied. To evaluate the effect of the prosthesis, a 3D model of the device was built and inserted in the L3-L5 model. The ROMs obtained with the intact model were imposed as maximal rotations to the instrumented model, therefore implementing the Panjabi hybrid protocol. Results: Increased ROMs at the implanted level and reduced ROMs at the adjacent level were predicted. A similar moment-rotation behavior was calculated after simulation of prosthesis insertion. No significant effect was predicted in terms of von Mises stress at the adjacent level after implantation of the prosthesis. Conclusions: Within the limitations of the models, the numerical results of this study predicted a preserved kinematics and stress at the adjacent segment, after insertion of the prosthesis. © 2010 Società Italiana Biomateriali. Source
Rossi A.,S.G. Moscati Hospital |
Garassino M.C.,Fatebenefratelli and Oftalmico Hospital |
Cinquini M.,Mario Negri Institute for Pharmacological Research |
Sburlati P.,Fatebenefratelli and Oftalmico Hospital |
And 4 more authors.
Lung Cancer | Year: 2010
Objective: To assess the role of maintenance or consolidation therapy in the treatment of small-cell lung cancer (SCLC), a meta-analysis of all published randomized clinical trials (RCTs) was performed in order to provide an overall meta-analysis and indirectly compare the effect of chemotherapy, interferons, and other biologic agents. Methods: Electronic databases were searched for publication reporting of RCTs comparing maintenance or consolidation therapy versus placebo or follow-up alone until December 2008. Hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS), with their relative 95% confidence intervals (CI), were derived. In the calculation of HRs, the " no maintenance" arm served as a reference. The a priori value of p<0.05 was chosen as significant level for statistical tests. Results: Twenty-one RCTs, encompassing 3,688 patients, were eligible for the present analysis: 11 RCTs employing chemotherapy, 6 interferons (4 alpha and 2 gamma), and 4 other biological agents. Overall, no statistical advantage in OS (HR 0.93, 95% CI 0.87-1.00; p=0.05) or in PFS (HR 0.98, 95% CI 0.91-1.06; p=0.63) was reported for maintenance or consolidation therapy. Statistical evidence of different effects among the four types of therapy was detected for OS (χ2 test for heterogeneity: 8.07 [3 df]; p=0.04), but not for PFS. A statistically significant reduction of mortality was detected in those studies assessing the efficacy of chemotherapy (HR 0.89, 95% CI 0.81-0.98; p=0.02) and of interferon-alpha (HR 0.78, 95% CI 0.64-0.96; p=0.02). Conclusions: The maintenance or the consolidation approach failed to improve the outcomes of SCLC. A survival advantage is suggested for maintenance chemotherapy and interferon-alpha, but its clinical impact needs to be confirmed by further studies. © 2010 Elsevier Ireland Ltd. Source