The Impact of Diabetes Mellitus on Patients Undergoing Cervical Spondylotic Myelopathy: A Meta-Analysis.

AIMS: We conducted a meta-analysis of eligible studies to compare the surgical outcomes between diabetic patients and non-diabetic patients who have undergone cervical spondylotic myelopathy (CSM). METHODS: A systematic literature search of PubMed, Embase, and Web of Science (up to February 10, 2016) was conducted. Eligible studies were case-control or cohort studies that compared the outcomes of cervical surgery between diabetic patients and non-diabetic patients. Weighted mean differences, risk ratios, and 95% CIs were calculated and heterogeneity was assessed with Cochrane Q chi-square test and I2 statistic. RESULTS: Six studies with a total of 38,680 patients were included in this meta-analysis. Pooled estimates showed that diabetic patients had significantly lower Japanese Orthopaedic Association (JOA) score change between pre- and post operation, and recovery rate than patients without diabetes. Moreover, diabetic patients had significantly increased risk of operative wound, epidural/wound hematoma, chronic lung disease, and cardiac complication. Other postoperative complications, including cerebrospinal fluid leakage and C5 radiculopathy, were not significantly different between the 2 groups. CONCLUSION: Diabetes mellitus decreased the JOA score change and recovery rate, as well as increased the risk of postoperative complications in patients undergoing CSM. Controlling diabetes mellitus before cervical spine surgery may lead to better outcomes.

Combination of activated Schwann cells with bone mesenchymal stem cells: the best cell strategy for repair after spinal cord injury in rats.

AIM: We aim to explore the repair effect of combined cell therapy using activated Schwann cells (ASCs) and bone mesenchymal stem cells (BMSCs) in traumatic spinal cord injury (SCI) in rats. MATERIALS & METHODS: ASCs and BMSCs were used for combined transplantation to treat acute SCI in rats, both of which can be obtained from SCI patients. ASCs were obtained by prior ligation of saphenous nerve and BMSCs by flush of the marrow cavity with Dulbecco's modified Eagle's medium solution. Our experiment in vitro confirmed that ASCs promoted BMSCs to differentiate into mature neural cells. It also indicates that BMSCs hold the potential to repair CNS injury. ASCs and BMSCs were co-transplanted into the injured epicenter of spinal cord made by the New York University (NYU) impactor machine using a 10 g × 50 mm drop weight. Complete ASCs, BMSCs and Dulbecco's modified Eagle's medium were also transplanted in rats with SCI as a control. Recovery of rat's hindlimb function was serially evaluated by Basso, Beattie, Bresnahan locomotor rating scale and footprint analysis. Changes of neurological potential were recorded by nerve electrophysiologic test. Improvement in the microenvironment of the injured spinal cord was evaluated by hematoxylin and eosin staining, glial fibrillary acidic protein staining, biotinylated dextran amine anterograde tracing and electron microscopy. RESULTS: Using biotinylated dextran amine anterograde tracing, we demonstrated that there were more regenerative axons of corticospinal tract surrounding and passing through the injured cavity to the caudal cord in the ASC-BMSC co-graft group than those in the other three groups, and we also confirmed this further by quantitative analysis. Immunostaining for glial fibrillary acidic protein showed the smallest population of astrocytes in the injury epicenter in the ASC-BMSC group compared with the other three groups. Relatively complete myelin sheaths and organelles were found in the ASC-BMSC group compared with the other three groups under electron microscopy. CONCLUSION: Effective co-transplantation of ASCs and BMSCs promotes functional recovery in rats' hindlimbs and reduces the formation of glial scar, and remyelinates the injured axons as compared with the other three groups. This conclusion was also supported by the observation of immunohistochemistry staining and electron microscopy, suggesting the possible clinical application for the treatment of spinal injury.

Novel multifunctional polyethylene glycol-transactivating-transduction protein-modified liposomes cross the blood-spinal cord barrier after spinal cord injury.

The blood-spinal cord barrier (BSCB) prevents many macromolecular agents from passing through to reach sites of injury in the spinal cord. This study evaluated the ability of a novel multifunctional liposome modified with polyethylene glycol (PEG) and transactivating-transduction protein (TAT) containing an iron core to cross the BSCB using a rat model of spinal cord injury. Rats were examined daily for a period of three days after spinal cord injury and injection of either the multifunctional modified liposome or control formulations using a 3.0 T magnetic resonance imaging spectrometer. A low signal was observed in the T2-weighted images. Prussian blue staining and flame atomic absorption spectrophotometry revealed that significantly more iron accumulated around the lesion site in the experimental group than the control groups (P < 0.05). The findings from this study suggest that this multifunctional liposome carrier can cross the BSCB to accumulate around the lesion site.

Regeneration of spinal cord with cell and gene therapy.

OBJECTIVE: Transplantation of fetal spinal cord cells (FSCC) can promote regeneration of injured spinal cord, while Schwann cells (SC) and some growth factors have a similar effect. However, the synergistic effects and optimal combination of these modalities have not yet been evaluated. In the current study, the efficiency of cell therapy of FSCC and/or SC, with/without growth factors (nerve growth factor [NGF] and brain-derived neurotrophic factor [BDNF]) was examined, with the aim of establishing an optimized protocol for spinal cord injury. METHODS: One hundred and twenty adult rats were randomly divided into six groups with 20 rats in each group. One week after the thoracic spinal cord injury model had been created, the rats were treated with different therapeutic modalities: Dulbecco's modified Eagles medium (DMEM) in Group I, FSCC in Group II, FSCC plus SC in Group III, FSCC plus SC over-expressing NGF in Group IV, FSCC plus SC over-expressing BDNF in Group V, and FSCC plus SC over-expressing both NGF and BDNF in Group VI. Subsequently, the rats were subjected to behavioral tests once a week after injury, while histology, immunohistochemistry and electron microscopy were performed at one and three month post-operation. RESULTS: Both SC and FSCC promoted regeneration of spinal cord injury when used separately, while a combination of the two types of cell resulted in better recovery than either alone. Both growth factors (NGF and BDNF) enhanced the outcomes of cell therapy, while synergistic effects meant that a combination of each individual component (group VI) achieved the best results according to locomotion scale, histology and immunoreactivity in the injured cords. CONCLUSION: SC, NGF and BDNF can enhance the outcome of FSCC therapy, while the combination of FSC with SC, NGF and BDNF is possibly the optimal protocol for clinical treatment of acute spinal cord injury.