Influence of Combination with 1q21 Amplification or-No in Patients with Newly Diagnosed MM on the Clinical Effecacy of Bortezomib-based induction chemotherapy and Long-Term Prognosis of Patients / 中国实验血液学杂志

OBJECTIVE@#To investigate the influence of influence of combination with 1q21 amplification or-no in patients with newly diagnosed MM on the clinical effecacy of bortezomib-based induction chemotherapy and long-term prognosis of patients.@*METHODS@#148 patients with newly diagnosed MM treated from January 2010 to May 2018 were selected and divided into 2 groups: group A (70 patients) without 1q21 amplification and group B (78 patients) with 1q21 amplification; and the survival benefit and influence on clinical efficacy of bortezomib were compared between 2 groups, and the factors influencing clinical prognosis in the patients with newly diagnosed MM were analyzed.@*RESULTS@#The median PFS and OS of patients in B group were significantly shorter than those in group A (P＜0.05). There was no significant difference in the median OS and PFS between patients with 1q21 amplification copies number =3 and ＞3 (P＞0.05). Multivariate Cox model analysis indicated that the adverse factors for OS were ISS staging, Hb levels, β2 microglobulin levels and 1q21 amplification respectively, and the adverse factors for PFS were Hb levels and 1q21 amplification respectively in patients with newly diagnosed MM (P＜0.05). The very good partial remission rate of newly diagnosed MM patients with 1q21 amplification and bortezomib-based induction chemotherapy were significantly higher than that in the patients without bortezomib-based induction chemotherapy (P＜0.05). The median PFS time of newly diagnosed MM patients with 1q21 amplification and auto-HSCT after bortezomib-based induction chemotherapy was significantly longer than that of patients without auto-HSCT (P＜0.05).@*CONCLUSION@#1q21 amplification should be the independent risk factor for poor prognosis of patients with newly treated MM. The application of bortezomib-containing induction chemotherapy in patients with 1q21 amplification can efficiently improve the remission rate, while auto-HSCT consolidation therapy may prolong patients' PFS.

Biomechanical characteristics analysis on discs with coflex fixation on the different segments of lower lumbar spine / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the biomechanical differences between the surgery and adjacent segments of intervertebral discs in the lower lumbar spine, which were implanted with Coflex into the segments of L4, and L5S1, respectively.</p><p><b>METHODS</b>Three finite-element models (the model of the intact lower lumbar sacrum,the L4.5 and L5S1 segments implanted by Coflex) were developed, respectively. According to the spinal three-column loading theory, three models were forced by the physiological loads of upright standing, flexion and extension. The stress of the different areas of the disc annulus, the changes of intervertebral dorsal height and the degree of nucleus pulposus pressure were compared and analyzed.</p><p><b>RESULTS</b>Coflex implanted into the L4.5 and L5S1 segments in compression and extension could both decrease the stress of the posterior area of intervertebral disc in the surgery segment, resist the changes of the intervertebral disc dorsal height and reduce the perssure of nucleus pulposus. Furthermore, the stress of the L5S1 segment decreased when Coflex fixed the L4.5 segment in extension. However, when Coflex fixed the L5S1 segment, the stress of L4.5 segment had no significant changes.</p><p><b>CONCLUSION</b>Coflex fixing the L4,5 and L5S1 segments can effectively decrease the stress of the surgery segmental discs, respectively. Furthermore, Coflex fixing L4,5 segment may play a biomechanical role in reducing the stress of L5S1 segment.</p>

Finite element model testing on Coflex dynamic fixation for L4/5 and L5/S1 segment of lower lumbar / 医用生物力学

Objective To simulate clinical operation and investigate feasibility of Coflex dynamic device for fixing L5/S1 segment of lower lumbar degenerative diseases. Methods The lower lumbar-sacral digital model was extracted from platform of the second generation of Chinese Digitized Human “Male No.23” data set, and three finite element (FE) models (the model of normal lower lumbar sacrum, L4/5 and L5/S1 segment fixed with Coflex) were developed respectively using a series of CAX software. According to the spinal three-column loading theory and the lower lumbar physiological behaviors, FE model tests were analyzed, validated and compared under the physiological load of upright standing, anteflexion and extension. Results The FE models of normal lower lumbar sacrum (Healthy), Coflex fixed-L4/5 segment (L4/5), Coflex fixed-L5/S1 segment (L5/S1) were developed, respectively. Based on biomechanical indexes (stability and compatibility) of the controlled trial for the FE model, the two Coflex-fixed FE models showed similar biomechanical effects for fixing the lower lumbar. Conclusions The controlled trials of FE models provide biomechanical evidence for the fixation of lower lumbar L5/S1 segment by Coflex dynamic device, which is of significance for application of Coflex in fixing L5/S1 segment in clinic.

Finite element analysis on internal fixation biomechanics for vertical sacrum fractures in the second generation of Chinese digitized human / 医用生物力学

Objective This study aims at comparing and optimizing postoperative stability and biomechanical compatibility in treating different types of vertically unstable sacrum fractures by using percutaneous posterior-ring tension-band steel plate and percutaneous iliosacral screw. MethodUsing CT and MR images of the second generation of Chinese digitized human “male No. 23”, the finite element models were developed respectively for two groups of vertical sacrum fractures of Denis Ⅰ,Ⅱ,Ⅲ zone with ipsilateral superior and inferior pubis ramus fractures treated with percutaneous posterior-ring tension-band steel plate (P-group) vs percutaneous iliosacral screw (S-group). The multi-solution finite element analysis and experiment validations were adopted on the basis of lumbosacral spinal three-column loading modes and sacroiliac joint physiologic behaviour. Results When simulating vertical sacrum fractures of Denis Ⅰ zone, von Mises stresses of internal fixation device of posterior and anterior rings of P-group were significantly increased, while the sacrum displacements were also increased compared to those in S-group. Whereas as simulating vertical sacrum fractures in Denis Ⅱand Ⅲ zones, von Mises stresses of fixator of both rings in P-group were lower than those of S-group, and the sacrum displacements were also remarkably decreased. Conclusions Considering internal fixation stability, mechanical compatibility for fracture healing and surgical procedure security, percutaneous iliosacral screw is more appropriate for the treatment of vertically unstable pelvis fractures with sacrum Ⅰzone injury, whereas percutaneous posterior tension-band steel plate is in favor of the treatment of vertically unstable pelvis fractures with sacrum Ⅱ and Ⅲ zone injuries.