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AIM:To dynamically observe and compare the relative changes of the indexes from the process of acute inflammation to chronic remodeling in asthmatic mice induced by ovalbumin ( OVA) .METHODS:Female BALB/c mice (n=60) were randomly divided into normal control group and asthma group .The mice in asthma group were sensi-tized and challenged by OVA , while the mice in normal group received equal volume of normal saline ( NS) .The challenge was performed for 3 consecutive days from the 21th day to observe the response of acute inflammation , and then the mice in different groups were challenged once per week for 5 weeks.Detailed comparisons of the dynamic changes of cell infiltra-tion, cytokine expression and airway remodeling were conducted .RESULTS:Compared with NS group , the mice in OVA group showed a predominantly eosinophilic infiltration into the airway lumen , increased production of Th 2-type cytokines , secretion of epithelial mucus and deposition of subepithelial collagen .In OVA challenge groups , the levels of inflammatory cells and inflammatory factors were remarkably higher in 24 d group, whereas the most obvious changes of goblet cell hyper-plasia and airway remodeling were observed in 52 d group.CONCLUSION:Acute asthma model is sufficiently induced by 3 consecutive days of OVA challenge protocol , which is accompanied with high levels of inflammatory cells and inflammato-ry factors.The OVA challenge protocol once per week for 5 weeks could induce a chronic asthma model with obvious airway remodeling .
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AIM: To investigate the effects of metformin on airway inflammation, remodeling and neovascularization in a mouse model of chronic asthma and its possible mechanisms.METHODS: BALB/c mice were randomly divided into saline group, ovalbumin (OVA) group and OVA+metformin group, with 8 in each.At the end of OVA exposure, blood and bronchoalveolar lavage fluid (BALF) were collected for the measurement of OVA specific IgE and leukocyte counts.Lung tissue sections were stained with hematoxylin-eosin, periodic acid-Schiff and Masson's trichrome to detect inflammatory cell infiltration, goblet cell hyperplasia, and collagen deposition around the airway, respectively.Immunohistochemistry was used to evaluate the number and percentage area of new blood vessels (CD31+), and the protein level of phosphorylated AMP-activated protein kinase (p-AMPK) in the airway.RESULTS: Compared with saline group, the eosinophil percentage and OVA specific IgE in serum in OVA group were all increased obviously (P<0.01).Metformin inhibited the above increases (P<0.05).Compared with control group, a marked increase in inflammation infiltration, PAS+ cells and collage deposition in the airway mucosa in OVA group were observed.Metformin partially relieved the above changes.CD31+ vessels in the wall of bronchi showed the abundance of blood vessels observed in OVA group compared with control group, which was suppressed by the treatment with metformin (P<0.05).The protein level of p-AMPK was reduced in the lung tissue challenged with OVA as compared with control group (P<0.05), while metformin increased the protein level of p-AMPK (P<0.01).CONCLUSION: The protein level of p-AMPK in the airway in OVA group is attenuated.Metformin effectively inhibits airway inflammation, remodeling and neovascularization possibly via activating AMPK signaling pathway.
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Objective To evaluate the value and feasibility of Microsim medical simulation training system in medical students' clinical thinking training. Method 96 students of 5-year program of medicine of Grade 2009 and Grade 2010 were the research object. These students were randomly divided into two groups (group A:After 3 weeks' clinical practice in respiratory medicine, taking 1 week Microsim training. group B: Taking 4 weeks clinical practice in respiratory medicine. Each group has 48 students.). The examination and teaching satisfaction of the two groups were observed after the end of the internship. SPSS 17.0 statistical software was used to analyze the collected data (measurement data matching t test, counting data by chi-square test). Results The Microsim system score: group A was (89.37±7.18), group B was (61.95±15.34). The difference between groups was statistically signifi-cant. The following scores suggested the assessment of students' ability of clinical thinking: ability to analyze problems [group A (89.95±4.02) vs. group B (75.51±6.34)], the ability to deal with the prob-lem [group A (78.81±8.09) vs. group B (59.67±9.33)], treatment scheme [group A (86.74±6.59) vs. group B (70.39±7.05)] and the treatment effect [group A (88.61±8.16) vs. group B (63.54±11.48)]. In these aspects, the two groups had statistically significant difference, but communication [group A (82.47 ±5.23) vs. group B (84.09 ±3.72)] had no statistically significant difference between the two groups. 89.6% (43) of the participants believed that the Microsim medical simulation training system could significantly improve the clinical thinking ability, but only 58.3% (28) of the students believed that the basic theory of knowledge could be consolidated. Conclusion Microsim medical simulation training system can improve the students' ability of clinical thinking and clinical comprehensive treat-ment ability. It can be used as an effective complement to clinical practice teaching.