Abstract： Objective To investigate the effect of intramyocardial injection of slow release microspheres of tannic acid （TA） on ventricular remodeling after acute myocardial infarction （AMI） in rats. Methods Slow release microspheres of TA were prepared and the release parameters in vitro were detected. AMI model in rats was induced. Eighty rats were enrolled and divided into 4 groups by random digital table：poly （lactic-co-glycolic acid） （PLGA） microspheres injection （PLGA group， n=24）， PLGA-TA microspheres injection （PLGA-TA group， n=24）， TA injection group （TA group， n=16） and normal saline injection group （NS group， n=16）. Heart function was evaluated by echocardiography after the injection. The structure of cardiac extracellular matrix （ECM） in the infarcted borderline area was evaluated at 4th week after the injection. Collagen content in the infarcted area was evaluated by hydroxyproline colorimetry assay at 2nd and 4th week after the injection. Results TA release was maintained at a constant rate from the microspheres for one month in vitro. Two weeks after the injection， left ventricular ejection fraction（LVEF）， left ventricular fraction shortening（LVFS）， left ventricular end-diastolic diameter（LVEDD） and left ventricular end-systolic diameter（LVESD） in PLGA-TA group and TA group were significantly better than those in the other two groups（P＜0.05）. Four weeks after the injection， LVEF， LVFS， LVEDD and LVESD in PLGA-TA group were significantly better than those in the other three groups （P＜0.05）. Four weeks after the injection， slow release microspheres of TA in the PLGA-TA group effectively improved the arrangement of ECM compared with TA group. Four weeks after the injection， collagen content in the infarcted area of PLGA-TA group was significantly higher than that in TA group（88.88±7.28 μg/mg dry weight vs. 72.43±9.02 μg/mg dry weight）， PLGA group（88.88±7.28 μg/mg drg weight vs. 71.97±6.06 μg/mg dry weight） and NS group（88.88±7.28 μg/mg dry weight vs. 68.86±7.55 μg/mg dry weight， F=7.162，P=0.003）， but there was no statistical difference in the collagen content of the infarcted area among TA group， PLGA group and NS group （P＞0.05） . Conclusion Intramyocardial injection of slow release microspheres of TA can maintain a constant release of TA for a comparatively long period， inhibit collagen matrix degradation， and effectively attenuate ventricular remodeling after AMI in rats.
The training of clinical teachers of general medicine is a key part of the construction of general medicine in our country. However, there is no existing mode for reference. West China Hospital of Sichuan University has completed one of the "Key National Public Health Projects-Training of Clinical Teachers of General Medicine in Sichuan Province". The project has searched for proper way in designing the teaching mode, organizing teaching resources, teaching evaluation and feedback, and training monitoring and management. Problems encountered during the process were analyzed and discussed for corresponding countermeasures. We believe this could be an experience for the future training to improve the quality in training clinical teachers of general medicine.
ObjectiveTo evaluate the predictors of generalized anxiety disorder (GAD) among teachers in 3 months after Lushan earthquake. MethodsA prospective cohort study was conducted to diagnostically evaluate the psychological sequelae and GAD during 14-20 days and 85-95 days after the earthquake. The possible predictive factors of psychological sequelae were assessed by a self-made questionnaire and the GAD was assessed by the GAD symptom criterion of M.I.N.I. in 3 months. The univariate and multivariate logistic regression analysis (ULRA, MLRA) were applied to analyze the predictors of GAD after the two-staged assessments. ResultsThere were a total of 319 teachers completed the two-staged assessments. The total response rate was 51.3%. Seventy teachers were diagnosed as GAD and the prevalence of GAD in 3 months was 21.9%. The predictive factors by ULRA included:male, older than 35 years old, having unlivable house, living in tents, sleeping difficulties, easy to feel sad, physical discomfort, loss of appetite, feeling short of social support, unable to calm down for working, feeling difficult for teaching, observing more inattention of students, and wanting to ask for a leave. The independent predictors by MLRA included:male, having unlivable house, feeling short of social support, and feeling difficult for teaching. ConclusionThe teachers have a higher likelihood of GAD after earthquake. It is essential to pay more attention to those male teachers, who feel short of social support and don't have a livable house thus to prevent the GAD at the early stage of post-earthquake.