Problem based learning(PBL) pedagogy has been widely used in medical teaching process.But how to best use and develop PBL teaching,many universities try actively.According to PBL philosophy and the disciplines characteristics,the department of Pathophysiology in Central South University designed and carried out CPBL(Case and Problem Based Learning,CPBL) pedagogy.From the perspective of students,the authors have compared the CPBL pedagogy with PBL pedagogy in other academies,and make some positive recommendations.

To ignite medical students' interest in pathophysiology,cultivate their creativity and ability in clinical practice,the Department of Pathophysiology in Xiangya School of Medicine of Central South University has implemented the units-teaching pattern in combination with problem-based learning(PBL)in 345 students enrolling in the school of continuing education of Central South University in 2006.The experiment has received positive feedback and wide approval from the students.

Objective:To investigate the effect of nucleolin on cardiac cell apoptosis in Type 2 diabetic cardiomyopathy mice.Methods:Mice were fed with high-fat and high-sugar food for 20 weeks (mice were injected intraperitoneally with 60 mg/kg streptozotocin in the 5th and 6th weeks) to establish a mouse model of Type 2 diabetes.The mice were divided into 4 groups:a wild type (WT) control group,a nucleolin transgenic (TG) control group,a WT diabetic group,a TG diabetic group.Diabetesrelated indicators were detected at the end of the 8th week.At the end of the 20th week,HE staining was used to observe myocardial morphological changes;TUNEL staining and caspase-3 activity were used to detect the extent of apoptosis of cardiac myocytes.Results:The level of fasting blood glucose was significantly increased in the diabetic group than that in the control group.In WT diabetic group,myocardial disarrangement,fragmentation and dissolution were observed (determined by HE staining);cellular apoptosis (determined by TUNEL staining and caspase-3 activity) also increased markedly in the WT diabetic group.Compared with the wild mice in the diabetic group,myocardial morphological changes and cardiac myocytes apoptosis were alleviated significantly.Conclusion:Nucleolin overexpression affectes the occurrence and development of diabetic cardiomyopathy through inhibition of cardiac myocyte apoptosis.

AIM:To construct myocardium-specific nucleolin ( Ncl) transgenic mice and to provide an animal model for the studies of the myocardial protection of nucleolin .METHODS:To create nucleolin transgenic mice , a myo-cardium-specific expression plasmid of nucleolin ( Alpha-MyHC clone 26-Ncl) was constructed .The gene type of transgenic mice was identified by PCR and the nucleolin protein level was tested by Western blotting .The myocardium morphology , heart weight index (HWI) and left ventricular pressure maximum rise rate were observed in nucleolin transgenic (TG) mice and wild-type ( WT) mice.RESULTS:We gained 4 transgenic mice (51, 52, 56 and 86 lines, only 52 line and 86 line were eugonic) by PCR.Western blotting analysis showed the expression of nucleolin up-regulated specifically in the myocardium .However , the myocardium morphology , HWI and left ventricular pressure maximum rise rate in the nucleolin transgenic mice were similar to those in the wild-type mice.CONCLUSION:We constructed myocardium-specific nucleo-lin transgenic mice successfully .

AIM: To investigate the effect of nucleolin on diabetic cardiomyopathy in mice.METHODS: A type II diabetic cardiomyopathy mouse model was prepared using a cardiac-specific nucleolin-overexpressing transgenic mice.The mice were divided into wild-type mouse control group, nucleolin transgenic mouse control group, wild-type mouse diabetes group and nucleolin transgenic mouse diabetes group.Wheat germ agglutinin (WGA) fluorescent dye, Masson staining and PowerLab system detection were used to further clarify the role of nucleolin on cardiac hypertrophy, fibrosis and cardiac function in type II diabetic cardiomyopathy mice.RESULTS: Compared with wild-type mouse control group, no significant increase in blood glucose level was found, while genetical myocardial cell hypertrophy was significantly attenuated in nucleolin transgenic mouse diabetes group.The collagen fibers were also significantly reduced, and hemodynamic indexes ± dp/dtmax, left ventricular end-diastolic pressure, left ventricular systolic pressure and heart rate were also improved.The above differences were statistically significant.CONCLUSION: Nucleolin may reduce the occurrence of myocardial hypertrophy and fibrosis, thus improving the cardiac function of diabetic cardiomyopathy mice.

Objective To study the influence of let-7b on cell proliferation and aerobic glycolysis of human melanoma cell A375.Methods Transfect A375 cell line with hsa-let-7b oligonucleotide or antisense.Glucose and lactate in medium were determined by spectrophotometry at 24 h and 48 h time point after transfection.The cell proliferation was determined by methylthiazol tetrazolium (MTT) assay.Results Over expression of let-7b in melanoma cell reduced cell proliferation notably,compared to the other groups by MTT(P ＜0.05).However,the glucose consumption and lactate production differences were not observed during 24 h or 48 h ( P ＞ 0.05 ),the blank control group transformed about 57％ and 43％ glucose to lactate during 24 h and 48 h.Conclusions Melanoma cell line A375 has notably aerobic glycolysis hallmark,let-7b could inhibit proliferation of melanoma cell line A375,but it may has no influence on glucose metabolism.

Objective To confirm whether or not let-7b and miR-199a were significantly associated with malignant melanoma growth and proliferation. Methods An over -expression plasmid and an inhibitor, which targeted on let-7b and miR-199a, was constructed. B16F10 cells were divided into seven groups: control group, let-7b plasmid group, miR-199a plasmid group, empty plasmid group, let-7b inhibitor group, miR-199a inhibitor group, inhibitor control group. Foreign gene was transfected into B16F10 cells, let-7b and miR-199a expression were validated from RNA level, protein level and cell level. Results The relative let-7b or miR-199a gene expression of the let-7b plasmid group (3.8776±0.1372)and miR-199a plasmid group (2.8660±0.2821)were significantly higher than control group (P＜0.05), the relative let-7b or miR-199a gene expression of the let-7b inhibitor group (0.2057±0.0263) and miR-199a inhibitor group(0.2656±0.0253) were significantly lower than control group(P＜0.05). The cyclinD1 expression of the let-7b plasmid group(2.023±0.315) and let-7b inhibitor group (1.857±0.377) were significantly higher than control group (0.997±0.041) (P＜0.05), whereas, the Met expression of themiR-199a plasmid group (5.19±0.309) and miR-199a inhibitor group (4.87±0.044) were significantly higher than control group (2.2±0.198) (P＜0.05). The let-7b plasmid group and miR-199a plasmid group B16F10 cell growth rate were slower than control group, especially on the third day after transfection, the growth rate gradually dropped to the lowest value (P＜0.05). In addition, the apoptosis rates of the let-7b plasmid group and miR-199a plasmid group reach to (11.8±1.19)% and (11.3±1.59)%,which were significantly higher than control group (P＜0.05). Conclusions let-7b and miR-199a may be a negative regulator on the B16F10 cell growth and proliferation.

OBJECTIVE: To detect the expression of nucleolin in cardiac hypertrophy rats induced by pressure overload. METHODS: A total of 40 SD rats with body weight 180 g and 220 g were recruited and randomly divided into 2 groups: a transverse aortic constriction (TAC) group and a sham surgery group. Cardiac hypertrophy model was employed by transverse aortic constriction surgery. Then 2 weeks and 4 weeks after the experiment, the heart mass index (HMI), left ventricle mass index (LVMI) were measured. β-MHC mRNA in the heart tissue was detected with RT-PCR. Nucleolin in the heart, brain and kidney was respectively detected with Western blot. RESULTS: Compared with the sham surgery group, HMI, LVMI in the TAC group increased significantly (P<0.01) 4 weeks after the surgery; the expression of β-MHC mRNA in the heart tissue increased (P<0.05) in the TAC group 4 weeks after the surgery; and the expression of nucleolin protein in the heart tissue of the TAC group was remarkably upregulated (P<0.05) 2 weeks after the surgery, with no change in the brain and kidney tissue between the 2 groups. CONCLUSION Expression of nucleolin protein has been upregulated in response to pressure overload, which may suggest that nucleolin plays a role in cardiac hypertrophy induced by pressure overload.
Animals ; Blood Pressure ; Cardiomegaly ; metabolism ; Myocardium ; metabolism ; Phosphoproteins ; metabolism ; RNA, Messenger ; RNA-Binding Proteins ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To investigate the nucleolus expression in the diabetic cardiomyopathy. METHODS: The rats were divided into a control group and a type II diabetic cardiomyopathy group (model group). In the model group, rats were fed with high-fat and high-sugar food (rats were intravenously injected with 60 mg/kg chain urea with cephalosporins in the 5th and 6th weeks in mice). The level of blood glucose was determined at the end of 8th week and the level of fasting blood glucose was examined at the end of 20th week. The ratio of the heart mass and body mass was calculated, and the pathological changes in myocardial morphology were observed. The immunohistochemical method and Western blot were used to detect the expression level of myocardial nucleolin. RESULTS: The level of fasting blood glucose was significantly increased in the diabetic model group than that in the control group (P<0.05). Rats in the model group were found hypertrophic cardic cells, with fracture, dissolusion, and disordered arrangement. Immunohistochemical staining and Western blot showed the protein levels of myocardial nucleolin in the model group were obviously higher than those in the control group (P<0.05). CONCLUSION Nucleolin may play a role in the pathogenesis and development of the diabetic cardiomyopathy.
Animals ; Blood Glucose ; Diabetes Mellitus, Experimental ; metabolism ; Diabetic Cardiomyopathies ; metabolism ; Myocardium ; pathology ; Phosphoproteins ; metabolism ; RNA-Binding Proteins ; metabolism ; Rats

Objective To provide reliable reference for improving teaching methods of case discus-sion, the teaching effectiveness evaluation on classroom-site segmented discussions of a patient case was completed in internal environment system. Methods The questionnaire survey was conducted among 250 clinic students of 8-year program and of 5-year program to investigate the teaching effectiveness following implementation of the teaching plan called"classroom-site segmented study of patient case debate competi-tion seminars". The contents of questionnaire survey included: the students' view on characteristics and advantages of this teaching plan and the reasons for favoring and supporting the plan. Investigation was conducted using an anonymous questionnaire. A total of 250 questionnaires were distributed and 247 valid questionnaires retrieved. Data collection and analysis were performed by using Excel and SPSS 17.0 statistical software, percentage of each observing parameter was calculated. Results ①The students' view on ad-vantages of the plan included following: reducing students' study burden by 78.5％ (194/247), increasing the students' engagement in class activities by 85.4％(211/247), improving teaching quality in class discus-sion by 80.5％ (198/246), enhancing team spirit among students by 78.5％ (194/246), expanding students' thinking and exploring space by 84.5％ (207/245), and similarity of this teaching plan to clinical diagnosis and treatment process reached to 84.0％(197/235). ②The students' reasons for favoring and supporting this plan included: reducing students' study burden by 83.4％ (206/247), improving teaching quality in class discussion by 72.4％(179/247), and training students' ability to search clinical information by 82.4％ (203/247). Conclusion Implementation of the teaching plan, "classroom-site segmented study of patient case debate competition seminars", in internal environment system has reduced students' study burden, improved teaching quality, and effectively trained students' clinic thinking, which is widely welcomed by students, therefore providing a positive valuable reference to other discussion class.