ABSTRACT
Objective:In this study, we established a reliable surgical procedure of lung ischaemia-reperfusion(IR) injury in rats. The research progress of different lung IR injury models and application value was also discussed.Methods:Twenty-eight adult SD rats were randomly divided into SHAM group and lung IR injury group(IR group), 14 rats in each group. In IR group, rats underwent tracheotomy under general anesthesia and received mechanical ventilation. Chest was opened in supine position, and pulmonary hilum was blocked for 30 minutes then the occlusion was removed. Samples were harvested after reperfusion for 45minutes. Rats in SHAM group received surgery and exposure of the right pulmonary artery, and experienced the same amount of time before the chest closed. Arterial blood gas was extracted postoperatively. Gross view of the lungs and pathological changes were observed, and the dry/wet ratio(W/D) was determined. Protein level of pro-inflammatory factors, markers in oxidative stress pathway, and endothelial functional markers in lung were tested by western blot analysis.Results:In IR group, there was pink foamy secretion in the airway, and the lungs exhibited signs of edema and congestion. In IR group, the alveolitis score was significantly increased, the W/D ratio was also increased, p38MAPK and NF-κB signaling pathways were activated, and the expression of TNF-α was significantly increased, while the expression of eNOS was significantly decreased.Conclusion:Left hilum clamping and bilateral reperfusion injury in lung is a practical animal model, it is a simple, low-cost and repeatable animal model for further studies. No microsurgical instruments were required during the procedure. Lung IR injury is characterized by oxidative stress response, inflammatory response and endothelial cell dysfunction.
ABSTRACT
A new mode of democratic alternating teaching for classroom use on college campuses was disscussed and some ways of solving the problems in the new mode of teaching were offered.
ABSTRACT
Objective To study the chemical constituents of Astragalus membranaceus var. mongholicus. Methods The constituents were isolated and purified by several chromatographic techniques and identified by chemicophysical properties and spectral analyses. Results Nine flavonoid compounds had been obtained from A. membranaceus var. mongholicus. They were determined as formononetin (Ⅰ), (3R)-8, 2′-dihydroxy-7, 4′-dimethoxy-isoflavane (Ⅱ), calycosin (Ⅲ), (6aR, 11aR)9, 10-dimethoxypterocarpan-3-O-?-D-glucoside (Ⅳ), 7, 2′-dihydroxy-3′, 4′-dimethoxy-isoflavane-7-O-?-D-glucoside (Ⅴ), formononetin-7-O-?-D-glucoside (Ⅵ), calycosin-7-O-?-D-glucoside (Ⅶ), pratensein-7-O-?-D-glucoside (Ⅷ), and genistin (Ⅸ), respectively. Conclusion Compound Ⅷ is obtained from the plants of Astragalus Linn. for the first time and compound Ⅱ is obtained from this plant for the first time. Compounds Ⅰ-Ⅶ show cell multiplication activity.