Repeated trans-spinal magnetic stimulation promotes microglial phagocytosis of myelin debris after spinal cord injury through LRP-1.

Spinal cord injury (SCI) is a serious trauma of the central nervous system. The clearance of myelin debris is a critical step in the functional recovery following spinal cord injury (SCI). Recent studies have begun to reveal critical roles for professional phagocytes in the central nervous system, microglia, and their receptors in the control of myelin debris in neurodegenerative disease. Repeated trans-spinal magnetic stimulation (rTSMS) has been demonstrated as a noninvasive SCI treatment that enhances tissue repair and functional recovery. In this study, we investigated the role and molecular mechanism of rTSMS on microglial phagocytosis of myelin debris in a rat SCI model. In our studies, we found that rTSMS significantly promoted the motor function recovery of SCI rats associated with the inhibition the neuroinflammation and glia scar formation. Immunofluorescence results further showed that the rTSMS promotes the clearance of myelin debris by microglia in vivo and in vitro. Additionally, receptor-associated protein (RAP), a Low-density lipoprotein receptor-related protein-1 (LRP-1) inhibitor, could cancel the accelerated microglial phagocytosis of myelin debris after rTSMS in vitro experiments. Simultaneously, Elisa's results and western blotting respectively showed that rTSMS significantly decreased the levels of soluble LRP-1(sLRP-1) and the LRP-1 splicing enzyme of ADAM17. In conclusion, rTSMS could promote the clearance of myelin debris by microglia through LRP-1 to improve the functional recovery of SCI rats.

Effect of Transition Metal Layer on Bending and Interfacial Properties of W/TiN/Ta-Laminated Composite.

The widespread applications of W in the fusion reactor are limited by its low-temperature brittleness, recrystallization brittleness, and irradiation-induced brittleness. Many toughening methods were used to improve the brittleness of W, such as adding second-phase particles, adding W fibers, preparing laminated composite, and so on. Among these, preparing laminated W-based composites has been proven to effectively improve both the low-temperature and high-temperature toughness of W. In this study, W/M/TiN/Ta-laminated composites with transition metal layer (M) were synthesized through the spark plasma sintering (SPS) at three different temperatures. The effects of nano-scale (Ni, Ti, and Cr) and micron-scale (Ni, Ti, and V) transition layers on the bending and interfacial properties of the W/M/TiN/Ta composite were studied via an electron probe micro-analyzer (EPMA) and transmission electron microscope (TEM). Compared with W/TiN/Ta, the flexural strength and strain of W/Ninm/TiN/Ta were increased by 25.6% and 17.6%, respectively. Ni, Ti, and V micron transition layers can improve the combination of the W-TiN interface and decrease the joining temperature. The micron V layer has the best strengthening effect. The flexural strength of W/V/TiN/Ta reached 1294 MPa, much higher than W/Ta's 1041 MPa.