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The objective of this study was to investigate the role of MAPKAP kinase 2 (MK2) and heat shock protein (HSP) HSP60 in the pathogenesis of a new model of severe acute pancreatitis (AP). MK2 plays a significant role in the regulation of cytokines. It has been shown that induction and expression of several HSPs can protect against experimental pancreatitis. Interplay between both systems seems of high interest. Mice with a homozygous deletion of the MK2 gene were used. Severe AP was induced by combined intraperitoneal injections of cerulein with lipopolysaccharide (LPS). Severity of AP was assessed by biochemical markers and histology. The serum IL-6 and lung myeloperoxidase (MPO) levels were determined for assessing the extent of systemic inflammatory response. Expression of HSP25, HSP60, HSP70, and HSP90 was analyzed by Western blotting. Repeated injections of cerulein alone or cerulein plus LPS (Cer+LPS) resulted in local inflammatory responses in the pancreas and corresponding systemic inflammatory changes with pronounced severity in the Cer+LPS group. Compared with the C57B1 wild-type mice, the MK2-/- mice presented with significant milder pancreatitis and attenuated responses of serum amylase and trypsinogen activity. Furthermore, serum IL-6 was decreased as well as lung MPO activity. Injection of LPS alone displayed neither pancreatic inflammatory responses nor alterations of pancreatic enzyme activities but evidently elevated serum IL-6 levels and increased lung MPO activity. In contrast hereto, in the MK2-/-mice, these changes were much milder. Increased expression of HSP25 and HSP60 occurred after induction of AP. Especially, HSP60 was robustly elevated after Cer+LPS treatment, in both MK2-/- and wild-type mice. Thus the homozygous deletion of the MK2 gene ameliorates the severity of acute pancreatitis and accompanying systemic inflammatory reactions in a new model of severe acute pancreatitis. Our data support the hypothesis that MK2 participates in the multifactorial regulation of early inflammatory responses in AP, independently of the regulation of stress proteins like HSP25 and HSP60 and most likely due to its effect on cytokine regulation. MAP kinases; cytokines; heat shock proteins; inflammation doi: 10.1152/ajpgi.00225.2009.

The ionic liquids used herein were alkyl-containing ammonium-aluminum chloride ionic liquids system, which were made by the reaction of short-chain alkyl ammonium salts and aluminum chloride. The factors influencing stability of gasoline and the importance of improving it were described in this article, so was the characteristic of ionic liquids. A novel way to improve the stability of gasoline using ionic liquids was studied herein, as well as the study of decreasing the basic nitrogen content and the sulfur content of mercaptan, treating the gasoline and decreasing the olefin content of gasoline with supported ionic liquids catalyst on a small scale. After treating, the sulfur content of gasoline decreased to 0 nearly, and the basic nitrogen content decreased greatly too, whereas the octane number (RON) of gasoline increased a little. To improve the catalysis of ionic liquids and prolong the using life of ionic liquids, a buffering agent was added into ionic liquids. Ionic liquids catalyst, as a green catalyst friendly to environment, can displace many other alkylation catalysts, decrease the olefin content of gasoline, and show their notable advantages: mild conditions, short reaction time, simple operation, easy separation of the products and the catalyst. [ABSTRACT FROM AUTHOR]