Neutrophils are considered to play a central role in ventilator-induced lung injury (VILI). However, the pulmonary consequences of neutrophil accumulation have not been fully elucidated. Matrix metalloproteinase-9 (MMP-9) had been postulated to participate in neutrophil transmigration. The purpose of this study was to investigate the role of MMP-9 in the neutrophilic inflammation of VILI. Male Sprague-Dawley rats were divided into three groups: 1) low tidal volume (LVT), 7 ml/kg of tidal volume (VT); 2) high tidal volume (HVT), 30 ml/kg of VT; and 3) HVT with MMP inhibitor (HVT+MMPI). As a MMPI, CMT-3 was administered daily from 3 days before mechanical ventilation. Degree of VILI was assessed by wet-to-dry weight ratio and acute lung injury (ALI) scores. Neutrophilic inflammation was determined from the neutrophil count in the lung tissue and myeloperoxidase (MPO) activity in the bronchoalveolar lavage fluid (BALF). MMP-9 expression and activity were examined by immunohistochemical staining and gelatinase zymography, respectively. The wet-to-dry weight ratio, ALI score, neutrophil infiltration, and MPO activity were increased significantly in the HVT group. However, in the HVT+MMPI group, pretreatment with MMPI decreased significantly the degree of VILI, as well as neutrophil infiltration and MPO activity. These changes correlated significantly with MMP-9 immunoreactivity and MMP-9 activity. Most outcomes were significantly worse in the HVT+MMPI group compared with the LVT group. In conclusion, VILI mediated by neutrophilic inflammation is closely related to MMP-9 expression and activity. The inhibition of MMP-9 protects against the development of VILI through the downregulation of neutrophil-mediated inflammation.

Successful organizational change is an important factor for maintaining sustainable competitive advantage and growth in today's rapidly changing business environment. The aim of this study is to investigate the relationship between empowering leadership and the commitment to organizational change of Korean employees and also examine whether risk-taking behavior mediates the above relationship. Moreover, we attempt to address the moderating role and mediated moderating role of task complexity in the relationship between risk-taking behavior and commitment to organizational change. The main hypotheses were tested using a cross-sectional design, with questionnaires administered to 275 employees working in Korean firms. The results of the empirical analysis revealed that empowering leadership was positively related to commitment to organizational change. The results also showed that risk-taking behavior positively mediated the relationship between empowering leadership and employees' commitment to organizational change. More importantly, we found that the indirect effect of empowering leadership on commitment to organizational change via risk-taking behavior was stronger when task complexity was high. Uncovering the relationship between empowering leadership and employees' commitment to organizational change through the mediating role of risk-taking behavior and the mediated moderating role of task complexity has useful theoretical and practical implications. The limitations of the study are discussed along with suggestions for future research.

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Nanocomposite membrane containing CNTs and GO exhibits considerably improved performances by the synergistic combinations of CNTs and GO, which can increase the dispersity in a polymeric matrix.