RESUMO
Objective:To explore an ideal method for establishing a mouse model of chronic atrophic gastritis (CAG).Methods:CAG mouse models were established with five different modeling methods ( N-methyl- N′-nitro- N-nitrosoguanide (MNNG), sodium salicylate, sodium deoxycholate, Helicobacter pylori infection, and combinations of them) in BALB/c and C57 mice. The effect of each modeling method was evaluated by histological observation of gastric mucosa, plasma biochemical parameters, inflammatory response score, and the expression of anti-inflammatory factors. Results:The results of histological observation of gastric mucosa showed that all of the 5 methods could successfully establish CAG mouse models. In BALB/c mice, compared with the healthy control group, significant features of CAG accompanied with intestinal metaplasia was found in the model group established by combination of MNNG-free drinking, 2% sodium salicylate and 20 mmol sodium deoxycholate. From the results of serological detection, compared with the normal control group, the mRNA expression levels of related anti-inflammatory factors interleukin-2, interleukin-10, interleukin-13 and growth differentiation factor-15 of each model group decreased, which indicated that the mice of each CAG model group had different degrees of inflammation. The results of plasma biochemical parameters indicated that plasma gastrin of each group decreased and the ratio of pepsinogen Ⅰ and pepsinogen Ⅱ significantly dropped. The above results demonstrated that in BLAB/c mice, MNNG-free drinking, 2% sodium salicylate and 20 mmol sodium deoxycholate was better than other four modeling methods. For C57 mice, it was also found that simple chemical drug mutagenesis and Helicobacter pylori replication method both could successfully establish CAG models. No matter from pathological observation, relative expression of anti-inflammatory factors and analysis of plasma biochemical parameters, the effects of combination of the two methods was better. Conclusion:The CAG mouse model established by MNNG-free drinking, 2% sodium salicylate and 20 mmol sodium deoxycholate can provide a certain reference for the establishment and application of mouse model in CAG experiments in the future for pharmacological research.
RESUMO
The clinical internship is an important transitional period for humanistic spirit cultivation of the medical students.But in this period there are some problems exposed.For example,there is the lack of transitional link in management; the clinical instruction doctors lack educational consciousness or guidance ability,the medical students pay little attention to enhancing the individual humanistic spirit level and there is a gap between theory and practice of humanistic spirit for them.Strengthening training for students,attaching importance to training,selection and incentive of clinical instruction doctors and revising handbook of clinical internship will help to solve the problems.