Optimization of medical educational objectives by improving summative assessment system / 生理学报

Summative assessment plays a decisive role in the educational assessment system, which is a yardstick to measure the cultivating goal of higher education. The rapid progress of modern society has put forward higher standard for higher medical education. Traditional summative assessment system with single dimension that focuses on evaluating the student's learning outcome via a standardized examination cannot meet the higher requirements for undergraduate medical education. We have improved the summative assessment system by optimizing the assessment content, criteria and method, as well as teachers' assessment skills and students' evaluation. The reform greatly increases the teaching quality and learning effect in our university.

Effect of meticulous management on prevention and control of healthcare-associated infection in pharmacy intravenous admixture service / 中国感染控制杂志

Objective To evaluate the application effect of meticulous management mode on prevention and control of infection related to pharmacy intravenous admixture service(PIVAS). Methods Qualified detection results of hygiene status of object surface,air culture quality,hand hygiene of medical staff in PIVAS in a hospital from Janu-ary 2014 to December 2016 were investigated,meticulous management measures were taken to intervene and analyze the detection results.Results The qualified rates of hand hygiene in 2014-2016 were 68.18%,81.82%,and 100.00% respectively,hand hygiene qualified rates in different years were statistically different(χ2=2.993,P=0.019). Qualified detection rates of surface of small objects,surface of horizontal laminar flow hoods,surface of biosafety cabinets,and air quality of dressing room Ⅰ and Ⅱ in PIVAS all increased to 100% in 2016.Conclusion Strengthening meticulous management of the internal work of PIVAS can effectively improve staff's standardized operation.

Danshensu delays the senescence of rat aortic endothelial cells via activation of SIRT1-SOD pathway / 生理学报

The present study was aimed to investigate the effect of pretreatment with Danshensu (DSS) on rat aortic endothelial cells (RAECs) senescence and the underlying mechanisms. Cultured RAECs at fourth and twelfth passages were taken as young and old groups, respectively. DSS and DSS+nicotinamide (DSS+N) groups were incubated with DSS and DSS in combination with nicotinamide, an inhibitor of silent information regulator 1 (SIRT1), from the fourth to twelfth passage, respectively. The cell status of senescence was determined by the senescence-associated β-galactosidase (SA β-gal) staining, and 4,6-diamino-2-phenyl indole (DAPI) fluorescent dye was used to detect senescence associated heterochromatin foci (SAHF) formation; Thiobarbituric acid (TBA) and colorimetric methods were used to evaluate malondialdehyde (MDA) and H₂O₂contents; Western blot was employed to analysis the expressions of xanthine oxidase (XOD), SIRT1 and superoxide dismutase 2 (SOD₂) in the RAECs. The results showed that, in comparison with young group, the old group exhibited higher SA β-gal positive and SAHF formation rates, as well as higher MDA and H₂O₂levels (P < 0.05 or P < 0.01), whereas DSS pretreatment reduced SA β-gal positive and SAHF formation rates, decreased MDA and H2O2 contents (P < 0.05 or P < 0.01). The protection of DSS was reversed by nicotinamide. Compared with the young group, the old group showed higher expression levels of XOD, but lower SIRT1 and SOD₂expression levels (P < 0.05 or P < 0.01). With the pretreatment of DSS, the expression of XOD was declined, and the expression levels of SIRT1 and SOD₂were elevated, while nicotinamide reversed the effects of DSS. These results suggest that DSS delays senescence of RAECs via up-regulation of SIRT1.

Exogenous hydrogen sulfide reduces vascular aging in D-galactose-induced subacute aging rats / 生理学报

The present study was aimed to observe the protective effect of exogenous hydrogen sulfide (H₂S) on vascular structural and functional changes of aorta in D-galactose-induced subacute aging rats. Adult male SD rats were randomly divided to five groups: the vehicle group, the D-galactose (D-gal) group, and the three NaHS groups treated with low (1 μmol·kg⁻¹·d⁻¹), middle (10 μmol·kg⁻¹·d⁻¹) or high (100 μmol·kg⁻¹·d⁻¹) dose of NaHS respectively. The D-gal group rats were given subcutaneously injection of 125 mg/kg D-gal per day for eight weeks to induce subacute aging model. In the NaHS group, D-gal was administered as above but with NaHS intraperitoneally injected at a dosage of 1, 10, 100 μmol·kg⁻¹·d⁻¹ respectively. Equivalent volumes of saline were administered per day for eight weeks in vehicle group. Morphological changes of aorta were observed by HE and Masson staining. The level of H₂S in serum, the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA), as well as anti-superoxide anions in vascular tissue were determined by spectrophotometry. Angiotensin II (AngII) levels in plasma were measured using competitive enzyme immunoassay. The expression of angiotensin II type 1 receptor (AT1R) in aorta was determined by Western blot. The results showed that the aging aortic morphologic changes in model rats were ameliorated in NaHS groups. Decreased vascular endothelial exfoliative cells and vascular smooth muscle cell (SMC) proliferation were shown in NaHS groups by HE staining. Masson staining analysis showed reduced relative contents of collagen fibers (P < 0.05) and SMC (P < 0.05) in NaHS groups. Compared to vehicle group, serum concentration of H₂S in D-gal group was decreased, while it was increased in NaHS groups after treatment with NaHS (P < 0.05). In the D-gal group, the concentration of AngII in plasma was significantly increased compared with that in vehicle group, while it was decreased in NaHS groups (P < 0.05). Moreover, levels of vascular tissue anti-superoxide anion and the activity of SOD were obviously higher, MDA was significantly lower in all NaHS treated groups than those in the D-gal group respectively (P < 0.05). Western blot analysis showed that the expression of AT1R was increased in D-gal group compared with that in vehicle group, while it was decreased after treatment with NaHS compared with that in D-gal group (P < 0.05). These results suggest that exogenous H₂S can ameliorate the age-related changes of aortic morphology, decrease the concentration of AngII in plasma, down-regulate the expression of AT1R in vascular tissue, and mitigate the level of oxidative stress. These changes delay the vascular aging in aging rats ultimately.

Exogenous hydrogen sulfide attenuates gastric ischemia-reperfusion injury via activation of K(ATP) channel / 生理学报

The present study aimed to investigate the protective effect and mechanism of hydrogen sulfide donor NaHS administration against gastric mucosal injury induced by gastric ischemia-reperfusion (GI-R) in rats. GI-R injury was induced by clamping the celiac artery of adult male SD rats for 30 min and followed by reperfusion for 1 h. The rats were randomly divided into sham group, GI-R group, NaHS group, glibenclamide group and pinacidil group. Gastric mucosal damage was analyzed with macroscopic injured area, deep damage was assessed with histopathology scores, and the hydrogen sulfide concentration in plasma was determined by colorimetric method. The results showed that pretreatment of NaHS significantly reduced the injured area and deep damage of the gastric mucosa induced by GI-R. However, NaHS did not significantly alter the levels of hydrogen sulfide in plasma 14 d after NaHS administration. The gastric protective effect of NaHS during reperfusion could be attenuated by glibenclamide, an ATP-sensitive potassium channel (K(ATP)) blocker. However, K(ATP) opener pinacidil inhibited the GI-R-induced injury. These results suggest that exogenous hydrogen sulfide plays a protective role against GI-R injury in rats possibly through modulation of K(ATP) channel opening.

Role of mitogen-activated protein kinases in the regulation of paraventricular nucleus to gastric ischemia-reperfusion injuries / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>We investigated the role in electrical stimulations of paraventricular nucleus (PVN) on gastric mucosal cells and the activity of mitogen-activated protein kinases (MAPKs) family members induced by gastric ischemia-reperfusion (GI-R). And we elucidated the molecular mechanisms of the protection of PVN from GI-R injuries.</p><p><b>METHODS</b>Sprague-Dawley rats were divided randomly into 4 groups: Group I, the sham-operated GI-R control group; Group II, the sham-operated electrical stimulations to PVN + sham-operated GI-R control group; Group III, the GI-R group; and Group IV, the electrical stimulations to PVN + GI-R group. In all of the experiments, the PVN was stimulated prior to the induction of GI-R. The GI-R model was established by clamping the celiac artery for 30 minutes to induce ischemia and then was released to allow reperfusion for 30 minutes, 1 hour, 3 hours and 6 hours, respectively. The gastric mucosal cellular apoptosis, proliferation, and the expression and activity of MAPKs protein were observed by immunohistochemistry and Western blotting, respectively.</p><p><b>RESULTS</b>Compared with the GI-R group, the application of electrical stimulations in the PVN significantly depressed gastric mucosal cellular apoptosis and enhanced gastric mucosal cellular proliferation following the 30-minute, 1-hour and 3-hour intervals of reperfusion; it also promoted the activation of p-ERK during the early phase of reperfusion but inhibited the activation of p-JNK1/2 and p-p38 following the 30-minute, 1-hour and 3-hour intervals of reperfusion.</p><p><b>CONCLUSIONS</b>The protection of PVN against GI-R injuries may attribute to the inhibition of apoptosis and the promotion of the proliferation of gastric mucosal cells during GI-R. This protective effect is mediated by activating the ERK pathway and depressing the JNK, p38 MAPK pathways of the gastric mucosal cells.</p>

Effects of gastric ischemia-reperfusion on gastric mucosal cellular apoptosis and proliferation in rats / 生理学报

The effect of gastric ischemia-reperfusion (GI-R) on gastric mucosal cellular apoptosis and proliferation was investigated using histological, immunohistochemical methods in Sprague-Dawley rats. The GI-R model was established by clamping the celiac artery for 30 min and reperfusing for 0, 0.5, 1, 3, 6, 24, 48, 72 h, respectively. Mild gastric mucosal injury was induced by ischemia alone. However, the injury worsened and reached the maximum at 1 h after reperfusion, almost simultaneously with the gastric mucosal cellular apoptosis increase and cellular proliferation decrease in gastric mucosa. Then, gastric mucosal cells began to repair by increasing gastric cellular proliferation, which achieved the maximum at 24 h after reperfusion. The mucosal lesions were almost completely repaired at about 72 h after reperfusion. These results indicate that the gastric mucosal injury after GI-R is mainly induced by reperfusion. The damaged gastric mucosa could initiate its repairing mechanism immediately through inhibiting cellular apoptosis and increasing the number of proliferative cells, which substitute the damaged cells gradually. The plerosis almost completes in three days after reperfusion showing a strong self-repair ability of gastric mucosa.