ABSTRACT
The hydrodeoxygenation transformation of lignin-derived phenols provides an attractive pathway for the production of renewable biofuels; however, harsh process conditions strongly hinder its practical application. Herein, we report a porous metal silicate (PMS) material, PMS-36, which consists of metallic nickel and Lewis acid AlIII sites inside the pores, demonstrating high efficiency in catalyzing the hydrodeoxygenation transformation of guaiacol under mild conditions. PMS-36 also exhibits robust stability, which can be attributed to the strong interaction and charge transfer between metallic Ni and AlIII Lewis acid sites inside the confined pores. This study shows the importance of synergistic and confinement effects in developing high-performance and stable heterogeneous catalysts for the chemical transformation of biomass and its derivatives.
ABSTRACT
OBJECTIVE: To observe the effect of N-acetylcysteine (NAC) on intestine injury induced by cardiopulmonary bypass (CPB) in rats. METHODS: Thirty-two rats were randomly divided into sham-operated group, NAC control group, CPB model group, and CPB plus NAC treatment group (n=8). In the latter two groups, the rats were subjected to CPB for 1 h. The rats received intraperitoneal injections of normal saline or NAC (0.5 g/kg) as appropriate for 3 successive days prior to CPB, and those in CPB plus NAC group were given NAC (100 mg/kg) in CPB prime followed by infusion at 20 mgsol;(kg·h) until the cessation of CPB. Intestinal and blood samples were collected 2 h after CPB for pathological analysis and measurement of intestinal concentrations of malondialdehyde (MDA), tumor necrosis factor (TNF)-α, interlukin (IL)-6 and activity of superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-Px) and serum levels of diamine oxidase (DAO). RESULTS: Evident oxidative stress and pathological damages of the intestines were observed in rats after CPB. NAC treatment obviously alleviated intestinal damages induced by CPB, decreased the levels of intestinal MDA, TNF-α, IL-6 and serum DAO and increased activity of SOD, GSH, and GSH-Px in the intestines. CONCLUSION: Perioperative NAC treatment can alleviate intestinal injury induced by CPB in rats by suppressing oxidative stress and inflammatory response.
