Spinal cord injury （SCI） is a devastating type of neurological trauma with limited therapeutic op- portunities. The pathophysiology of SCI involves primary and secondary mechanisms of injury. Among all the secondary...Spinal cord injury （SCI） is a devastating type of neurological trauma with limited therapeutic op- portunities. The pathophysiology of SCI involves primary and secondary mechanisms of injury. Among all the secondary injury mechanisms, the inflammatory response is the major contrib- utor and results in expansion of the lesion and further loss of neurologic function. Meanwhile, the inflammation directly and indirectly dominates the outcomes of SCI, including not only pain and motor dysfunction, but also preventingneuronal regeneration. Microglia and macrophages play very important roles in secondary injury. Microglia reside in spinal parenchyma and survey the microenvironment through the signals of injury or infection. Macrophages are derived from monocytes recruited to injured sites from the peripheral circulation. Activated resident microglia and monocyte-derived macrophages induce and magnify immune and inflammatory responses not only by means of their secretory moleculesand phagocytosis, but also through their influence on astrocytes, oligodendrocytes and demyelination. In this review, we focus on the roles of mi- croglia and macrophages in secondary injury and how they contribute to the sequelae of SCI.展开更多
Surface structures of Pt-Sn and Pt-Fe bimetallic catalysts have been investigated by means of Mssbauer spectroscopy, Pt-L<sub>Ⅲ</sub>-edge EXAFS and H<sub>2</sub>-adsorption. The results sho...Surface structures of Pt-Sn and Pt-Fe bimetallic catalysts have been investigated by means of Mssbauer spectroscopy, Pt-L<sub>Ⅲ</sub>-edge EXAFS and H<sub>2</sub>-adsorption. The results showed that the second component, such as Sn or Fe, remained in the oxidative state and dispersed on the γ-Al<sub>2</sub>O<sub>3</sub> surface after reduction, while Pt was completely reduced to the metallic state and dispersed on either the metal oxide surface or the γ-Al<sub>2</sub>O<sub>3</sub> surface. By correlating the distribution of Pt species on different surfaces with the reaction and adsorption performances, it is proposed that two kinds of active Pt species existed on the surfaces of both catalysts, named M<sub>1</sub> sites and M<sub>2</sub> sites. M<sub>1</sub> sites are the sites in which Pt directly anchored on the γ-Al<sub>2</sub>O<sub>3</sub> surface, while M<sub>2</sub> sites are those in which Pt anchored on the metal oxide surface. M<sub>1</sub> sites are favorable for low temperature H<sub>2</sub> adsorption, and responsible for the hydrogenolysis reaction and carbon deposition, while M<sub>2</sub> sites which adsorb more H<sub>2</sub> at higher展开更多
基金supported by grants from National Institutes of Health(R01GM100474)the New Jersey Commission on Spinal Cord Research(CSCR13IRG006)
文摘Spinal cord injury （SCI） is a devastating type of neurological trauma with limited therapeutic op- portunities. The pathophysiology of SCI involves primary and secondary mechanisms of injury. Among all the secondary injury mechanisms, the inflammatory response is the major contrib- utor and results in expansion of the lesion and further loss of neurologic function. Meanwhile, the inflammation directly and indirectly dominates the outcomes of SCI, including not only pain and motor dysfunction, but also preventingneuronal regeneration. Microglia and macrophages play very important roles in secondary injury. Microglia reside in spinal parenchyma and survey the microenvironment through the signals of injury or infection. Macrophages are derived from monocytes recruited to injured sites from the peripheral circulation. Activated resident microglia and monocyte-derived macrophages induce and magnify immune and inflammatory responses not only by means of their secretory moleculesand phagocytosis, but also through their influence on astrocytes, oligodendrocytes and demyelination. In this review, we focus on the roles of mi- croglia and macrophages in secondary injury and how they contribute to the sequelae of SCI.
文摘Surface structures of Pt-Sn and Pt-Fe bimetallic catalysts have been investigated by means of Mssbauer spectroscopy, Pt-L<sub>Ⅲ</sub>-edge EXAFS and H<sub>2</sub>-adsorption. The results showed that the second component, such as Sn or Fe, remained in the oxidative state and dispersed on the γ-Al<sub>2</sub>O<sub>3</sub> surface after reduction, while Pt was completely reduced to the metallic state and dispersed on either the metal oxide surface or the γ-Al<sub>2</sub>O<sub>3</sub> surface. By correlating the distribution of Pt species on different surfaces with the reaction and adsorption performances, it is proposed that two kinds of active Pt species existed on the surfaces of both catalysts, named M<sub>1</sub> sites and M<sub>2</sub> sites. M<sub>1</sub> sites are the sites in which Pt directly anchored on the γ-Al<sub>2</sub>O<sub>3</sub> surface, while M<sub>2</sub> sites are those in which Pt anchored on the metal oxide surface. M<sub>1</sub> sites are favorable for low temperature H<sub>2</sub> adsorption, and responsible for the hydrogenolysis reaction and carbon deposition, while M<sub>2</sub> sites which adsorb more H<sub>2</sub> at higher
