Forty three medical graduates from Hainan Medical University participating in the standardized general practice residency training in 2015 and 2016 were randomly divided into study group (n=22) and control group (n=21). The study group received a mid-term assessment and formative assessment, and the control group received the final assessment only. At the end of the six months of training, the scores of the mid-term assessment in study group were significantly higher than those in the control group [(82.9±8.4) vs. (75.5±10.2), t=12.706, P<0.01]. A questionnaire survey was conducted among the participants in study group, 86.4% of them recognized and supported the formative assessments. Formative assessment can improve the teaching quality of general practice residency training. The trainees have a positive attitude towards this assessment mode.

OBJECTIVE： To observe the protective effect of atorvastatin-induced increase of EPC-MVs on myocardial cells in ST-segment elevation myocardial infarction （STEMI） patients， and to investigate its potential mechanism. METHODS： Totally 168 STEMI patients was collected from our hospital during Feb. 2015-Feb. 2018， and then divided into group A （88 cases） and group B （94 cases） according to the dose of atorvastatin. All patients received percutaneous coronary intervention， and then given Bivaleridine for injection， Clopidogrel bisulfate tablets and Atorvastatin calcium tablets. Group A was given Atorvastatin calcium tablets 20 mg， once a day. Group B was given Atorvastatin calcium tablets 20 mg， twice a day. A treatment course lasted for 30 d， and two groups were treated for 3 courses at least. The levels of blood lipid （TC， LDL-C， HDL-C） （before treatment and 30th， 60th， 90th day after treatment） and the number of EPCs positive cells （30th， 60th day after treatment） were observed in 2 groups. The expression of miRNA of EPC-MVs （60th day after treatment） was detected， and the expression difference of miRNA were validated. Target gene and KEGG pathway enrichment of miRNA with most significant expression difference were analyzed， and the effects of it on the proliferation of cardiac HCM-a cells were evaluated. The occurrence of ADR was recorded in 2 groups. RESULTS： Totally 8 patients withdrew from the study in group A， and 6 patients in group B. There was no statistical significance in the levels of TC， LDL-C and HDL-C or the number of EPCs positive cells in peripheral blood between 2 groups before treatment or 30th day after treatment （P＞0.05）. After treatment， the level of HDL-C in 2 group （60th and 90th day after treatment） and the number of EPCs positive cells in peripheral blood in group B （60th day after treatment） were increased significantly， and group B was significantly higher or more than group A at the same time point （P＜0.05）. Microarray analysis showed that compared with group A， 16 miRNAs expressed more than 1.5 times differentially in EPC-MVs of group B， 7 of which were up-regulated and 9 down-regulated. Top five differentially expressed genes were hsa-miR-126 （up-regulated）， hsa-miR-1275 （up-regulated）， hsa-miR-7704 （down-regulated）， hsa-miR-105-5p （down-regulated）， and hsa-miR-3180 （down-regulated）. Fluorescence quantitative polymerase chain reaction results showed that compared with group A， relative expression of hsa-miR-126 and hsa-miR-1275 in group B were increased significantly； and relative expression of hsa-miR-7704， hsa-miR-105-5p and hsa-miR-3108 were decreased significantly （P＜0.05）. The expression difference of hsa-miR-126 was the most significant， and its target genes included Ang-1， PDGF， p38 MAPK， Smad2/3， HIF-1， TGF-β， etc. The signaling pathways involved in regulation mainly included angiogenesis signaling pathway， chronic myelogenous leukemia related pathway， renal epithelial cell carcinoma related pathway and so on. CCK-8 test showed that the optical density （OD） of cells in hsa-miR-126 specific interfering substance group was decreased significantly， and the OD value of cells in simulated substance group was increased significantly， compared with blank group （P＜0.05）. There was no statistical significance in the incidence of ADR as diarrhea， nausea and vomiting， rash， etc. （P＞0.05）. CONCLUSIONS： Different doses of atorvastatin can regulate the level of HDL-C， and large dose of atorvastatin can increase the number of EPCs significantly， but dose not influence the safety of drug use. This effect may be associated with up-regulating the expression of hsa-miR-126 in EPC-MVs so as to promoting the proliferation of myocardial cells.

Objective: To investigate the effect of peroxide reductase 1 (Prdx1) on myocardial hypertrophy and fibrosis in spontaneously hypertensive rats，and to analyze its mechanism． Methods: Forty five SHR rats were randomly divided into model group (SHR group) ，AAV9-NC group and AAV9-Prdx1 group．There were 15 WKY rats in each group，and the other 15 Wistar Kyoto rats were set as the control group．The rats in each group were administered continuously for 8 weeks，and the indexes of cardiac function were detected by echocardiography ; The mean blood pressure and myocardial hypertrophy were measured ; HE staining and Masson staining were used to observe the histomorphology and fibrosis of rat myocardium ; The indexes of oxidative stress in rat serum were detected by ELISA ; The expression level of Prdx1 mRNA in rat myocardium was detected by qRT-PCR ; Western blot was used to detect the expression of Prdx1 protein and nuclear factor E2 related factor 2 (Nrf2) / heme oxygenase-1 (HO-1) signaling pathway related proteins in rat myocardium. Results: Compared with the Control group，the expression of Prdx1 mRNA and protein ，left ventricular ejection fraction ( EF) and left ventricular shortening rate ( FS) decreased in SHR group (P＜0. 05) ，the mean blood pressure，heart mass index ( HMI) and left ventricular mass index (LVMI) of rats increased (P＜0. 05) ，and there were obvious pathological damage and collagen fiber deposition in myocardial tissue．The activities of superoxide dismutase (SOD) and glutathione peroxidase ( GSH-Px) in rat serum decreased，and the content of malondialdehyde (MDA) increased (P＜0. 05) ; The expression of Nrf2， HO-1 and quinone oxidoreductase 1 (NQO1) protein decreased in myocardial tissue (P＜0. 05) ．Compared with SHR group，the expression of Prdx1 mRNA and protein，EF and FS in myocardial tissue of AAV9-Prdx1 group increased (P＜0. 05) ，the mean blood pressure，HMI and LVMI of rats decreased (P＜0. 05) ，and myocardial tissue injury and myocardial fibrosis improved ; The activities of SOD and GSH-Px in rat serum increased，while the content of MDA decreased (P＜0. 05) ; The expression of Nrf2，HO-1 and NQO1 protein increased in myocardial tissue (P＜0. 05) ． Conclusion Overexpression of Prdx1 can reduce myocardial hypertrophy and fibrosis and improve cardiac function in SHR rats．Its mechanism may be related to activating Nrf2 / HO-1 signaling pathway and inhibiting oxidative stress response.

Objective To investigate the neuroprotective effect of methylene blue on diabetic retinopathy in rats. Methods Thirty SD rats were randomly divided into blank, control and experimental groups. The control and experimental groups were induced with diabetes by streptozotocin (STZ) intraperitoneal injection. After 6 weeks of successful modeling, the experimental group received intravitreal injection of methylene blue at a dose of [0.2 mg/(kg.d)], while the control group received an equal amount of dimethyl sulfoxide (DMSO) intravitreal injection, both continuously injected for 7 days. ELISA was used to detect the levels of retinal superoxide dismutase (SOD), 8-iso-prostaglandin F2alpha (iPF2α) and interleukin-1β (IL-1β) in rats. Western blot analysis was used to detect the expression of retinal extracellular signal-regulated kinase 1/2 phosphorylation (p-ERK1/2) and phosphorylated protein kinase B (p-AKT), and PAS staining was used to detect retinal morphological changes. Results Compared with the blank group rats, the retinal SOD activity in the control and experimental group rats was significantly reduced. iPF2α, IL-1β and p-ERK1/2 level increased, while p-AKT level decreased. Compared with the control group, the SOD activity of the experimental group rats increased. iPF2α and IL-1β level went down, while p-ERK1/2 and p-AKT level went up significantly. The overall thickness of the retinal layer and the number of retinal ganglion cells were significantly reduced. Conclusion Methylene blue improves diabetic retinopathy in rats by reducing retinal oxidative stress and enhancing ERK1/2 and AKT phosphorylation.
Rats ; Animals ; Diabetic Retinopathy/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Mitogen-Activated Protein Kinase 3/metabolism* ; Interleukin-1beta/metabolism* ; Methylene Blue/pharmacology* ; Phosphorylation ; Rats, Sprague-Dawley ; MAP Kinase Signaling System ; Diabetes Mellitus, Experimental/drug therapy* ; Superoxide Dismutase/metabolism*