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Background: Olfactory ensheathing cell (OEC) transplantation is a promising or potential therapy for spinal cord injury (SCI). However, the effects of injecting OECs directly into SCI site have been limited and unsatisfied due to the complexity of SCI. To improve the outcome, proper biomaterials are thought to be helpful since these materials would allow the cells to grow three-dimensionally and guide cell migration., Methods: In this study, we made a new peptide hydrogel scaffold named GRGDSPmx by mixing the pure RADA16 and designer peptide RADA16-GRGDSP solution, and we examined the molecular integration of the mixed nanofiber scaffolds using atomic force microscopy. In addition, we have studied the behavior of OECs in GRGDSPmx condition as well as on RADA16 scaffold by analyzing their phenotypes including cell proliferation, apoptosis, survival, and morphology., Results: The experimental results showed that GRGDSPmx could be self-assembled to form a hydrogel. Inverted optical microscopic and scanning electron microscopic analyses showed that OECs are viable and they proliferate within the nanostructured environment of the scaffold. Thiazolyl blue (MTT) assay demonstrated that OEC proliferation rate was increased on GRGDSPmx scaffold compared with the pure RADA16 scaffold. In addition, OECs on GRGDSPmx scaffolds also showed less apoptosis and maintained the original spindle-shaped morphology. Calcein-AM/PI fluorescence staining revealed that OECs cultured on GRGDSPmx grew well and the viable cell count was 95%., Conclusion: These results suggested that this new hydrogel scaffold provided an ideal substrate for OEC three-dimensional culture and suggested its further application for SCI repair.

Background: Although various systemic and local factors such as abnormal carbohydrate or calcium metabolism, aging, and hormonal disturbances have been suggested as causes of ossification of the posterior longitudinal ligament (OPLL), the etiology of OPLL is not fully understood. The purpose of this study was to investigate whether bone morphogenetic protein (BMP)-2 is a candidate gene to modify the susceptibility of OPLL and the mechanism of signal transduction in ossification., Methods: A total of 420 OPLL patients and 506 age- and sex-matched controls were studied. The complete coding sequence of the human BMP-2 gene was analyzed using polymerase chain reaction (PCR) and direct sequencing. All single nucleotide polymorphisms (SNPs) were detected and genotyped. BMP-2 expression vectors containing positive polymorphisms were constructed and transfected into the C3H10T1/2 cells. The expression of BMP-2 and the Smad signal pathway in positive cell clones were detected by Western blotting. The alkaline phosphatase (ALP) activity was determined using quantitative detection kits., Results: The frequencies for the 109T > G and 570A > T polymorphisms were different between the case and control groups. The "TG" genotype in 109T > G polymorphism is associated with the occurrence of OPLL, the frequency of the "G" allele is significantly higher in patients with OPLL than in control subjects (P < 0.001). The "AT" genotype in 570A > T polymorphism is associated with the occurrence of OPLL, the frequency of the "T" allele is significantly higher in patients with OPLL than in control subjects (P = 0.005). Western blotting analysis revealed that the expression of P-Smad1/5/8 protein transfected by wild-type or mutant expression vectors were significantly higher than control groups (P < 0.05), but there was no statistical difference in each experimental group (P > 0.05). The expression of Smad4 protein transfected by wild-type or mutant expression vectors was significantly higher than control groups (P < 0.05). The expression of Smad4 protein transfected by pcDNA3.1-BMP2 (109G) and pcDNA3.1-BMP2 (109G, 570T) was significantly higher than the other experimental groups (P < 0.05). The increase in ALP activity has been detected in pcDNA3.1-BMP2 (109G) and pcDNA3.1-BMP2 (109G, 570T) transfected cells up to 4 weeks after stable transfection. Activity of ALP was (30.56 ± 0.46) nmol×min(-1)×mg(-1) protein and (29.62 ± 0.68) nmol×min(-1)×mg(-1) protein, respectively. This was statistically different compared with the other experimental groups (P < 0.05)., Conclusions: BMP-2 is the predisposing gene of OPLL. The "TG" genotype in the 109T > G and the "AT" genotype in the 570A > T polymorphisms are associated with the occurrence of OPLL. The 109T > G polymorphism in exon-2 of the BMP-2 gene is positively associated with the level of Smad4 protein expression and the activity of ALP. The Smad mediated signaling pathway plays an important role during the pathological process of OPLL induced by SNPs of BMP-2 gene.

This case report describes a 44-year-old woman with primary spinal cord malignant melanoma localized in the lumbar region. This is a very rare lesion. The patient presented with back pain and slight weakness in her lower extremities. Magnetic resonance imaging showed hyperintense signals on T1-weighted images and hypointense signals on T2-weighted images. The entire tumor was removed surgically. The patient's postoperative clinical examination revealed mild neurological improvements. Histopathological investigations confirmed the tumor was a malignant melanoma. When treating common lesions of the lumbar spinal cord with a benign appearance, surgeons should be aware of the potential for malignant tumors.