Spastin interacts with collapsin response mediator protein 3 to regulate neurite growth and branching.

Cytoskeletal microtubule rearrangement and movement are crucial in the repair of spinal cord injury. Spastin plays an important role in the regulation of microtubule severing. Both spastin and collapsin response mediator proteins can regulate neurite growth and branching; however, whether spastin interacts with collapsin response mediator protein 3 (CRMP3) during this process remains unclear, as is the mechanism by which CRMP3 participates in the repair of spinal cord injury. In this study, we used a proteomics approach to identify key proteins associated with spinal cord injury repair. We then employed liquid chromatography-mass spectrometry to identify proteins that were able to interact with glutathione S-transferase-spastin. Then, co-immunoprecipitation and staining approaches were used to evaluate potential interactions between spastin and CRMP3. Finally, we co-transfected primary hippocampal neurons with CRMP3 and spastin to evaluate their role in neurite outgrowth. Mass spectrometry identified the role of CRMP3 in the spinal cord injury repair process. Liquid chromatography-mass spectrometry pulldown assays identified three CRMP3 peptides that were able to interact with spastin. CRMP3 and spastin were co-expressed in the spinal cord and were able to interact with one another in vitro and in vivo. Lastly, CRMP3 overexpression was able to enhance the ability of spastin to promote neurite growth and branching. Therefore, our results confirm that spastin and CRMP3 play roles in spinal cord injury repair by regulating neurite growth and branching. These proteins may therefore be novel targets for spinal cord injury repair. The Institutional Animal Care and Use Committee of Jinan University, China approved this study (approval No. IACUS-20181008-03) on October 8, 2018.

Revalidation of CoaguChek XS plus system for INR monitoring in Taiwanese patients: effects of clinical and genetic factors.

BACKGROUND: In this study, we evaluated the performance of a point-of-care device, the CoaguChek XS Plus system, in the determination of prothrombin time and international normalized ratio (INR) based on ISO17593: 2007 criteria in Taiwanese patients. The underlying clinical and genetic factors were also investigated. METHODS: Fifty patients receiving warfarin therapy were enrolled in this study. The accuracy of the CoaguChek XS Plus system was evaluated with linear regression analysis and bias plot by comparing with the data measured using Sysmex CA-1500. The clinical and genetic factors that may have caused a bias of ΃ 0.5 INR were evaluated with Fisher's exact test. RESULTS: From the 50 patients, 93 INR values were collected by each method. Linear regression analysis indicated a high correlation with r = 0.96, a slope of 1.05, and an intercept of - 0.14. Eight patients showed an INR bias ≥0.5 between the two methods. Only aspartate aminotransferase (AST) >34 U/L (3/8, 37.5% vs. 3/42, 7.1%; p = 0.044) and alanine aminotransferase (ALT) >36 U/L (3/8, 37.5% vs. 3/42, 7.1%; p = 0.044) were significantly different from each other. No differences were observed for hypoalbuminemia, elevated creatinine, anemia, and the polymorphisms of VKORC1 and CYP2C9. CONCLUSIONS: The CoaguChek XS Plus system presented results that were comparable with those obtained using laboratory CA-1500 method. Both methods fell within INR in the range of 2-4.5 defined by ISO17593:2007 and the clinically recognized therapeutic INR range of 2-3.5. Elevated AST and ALT levels might have interfered with the INR results.

Biomechanical assessment of unilateral pedicle screws plus contralateral transfacetopedicular screws after transforaminal lumbar interbody fusion with two cages.

OBJECTIVE: To assess the biomechanical stability of unilateral pedicle screws (UPS) plus contralateral transfacetopedicular screws (TFPS) after transforaminal lumbar interbody fusion (TLIF) with two cages. METHODS: Range of motion (ROM) testing was performed in 28 fresh-frozen human cadaveric lumbar spine motion segments. The sequential test configurations included supplemental constructs after TLIF such as UPS, UPS plus contralateral TFPS and bilateral pedicle screws (BPS). All test specimens were fixated in the normal lordotic lignment, then mounted in a three-dimensional (3-D) motion testing machine and fixed to the load frame of a six degrees of freedom spine simulator. Each of the test constructs were subjected to three load-unload cycles in each of the physiologic planes generating flexion-extension, right-left lateral bending and right-left axial rotation load-displacement curves. Statistical analysis was performed on the ROM data. Comparison of data was performed by repeated-measures analysis of variance for independent samples followed by Bonferroni analysis for multiple comparison procedures. RESULTS: The ROMs for UPS, BPS and UPS plus TFPS fixation after TLIF were significantly smaller than those of the intact spine in all modes. The ROM for UPS plus TFPS fixation was between the largest for UPS and the smallest for BPS. The differences between ROMs of UPS and UPS plus TFPS were significant for both lateral bending and rotation. There were no significant differences between BPS and UPS plus TFPS in any mode. CONCLUSION: Because the UPS construct provides the least stability, especially during lateral bending and rotation, it should be used prudently. After TLIF with two cages, UPS plus TFPS provides stability comparable to that of TLIF with BPS. It is thus an acceptable option in minimally invasive surgery.