Problem-based and student-centered learning patten brings new challenges to the both sides of teaching and learning.Clinical probation is the first step of medical students.The problem-based learning patten is used to clinical probation and achieves good results.It helps to improve medical students' quality and should be applied in China medical education.

Objective:To explore influence of monotherapy or combined use of telmisartan and pyridoxamine on aor-tic remodeling in spontaneously hypertensive rats (SHR)and its possible mechanism.Methods:A total of 48 male SHE were randomly and equally divided into hypertension control group,telmisartan group,group,and telmisartan+ group (combined treatment group). Kyoto Wistar rats of the same age and gender were regarded as normal blood pressure control group (normal control group). Thoracic aortic section were examined by related staining af-ter 16 weeks intervention to calculate the ratio of aortic wall thickness to radius of lumen (Tw/Rl),the ratio of wall area to lumen area (W/L),and the area ratio of media elastic fiber/collagen fiber. Concentrations of related en-zymes and receptor etc. of abdominal aortic were measured.Results:Compared with hypertension control group, there was significant rise in ratio of media elastic fiber/collagen fiber area and significant reduction in media collagen fiber/media area ratio in telmisartan group,pyridoxamine monotherapy group and combined treatment group,and there were significant decrease in Tw/Rl [(0.17±0.02)vs. (0.12±0.01)]and W/L [(0.29±0.03)vs. (0.22± 0.02)]ratios in combined treatment group,P <0.05 or <0.01;immunohistochemistry indicated that there were significant reductions in thoracic aortic receptor of advanced glycation end products (RAGE) [(0.24±0.03)vs.(0.17±0.03)]and extracellular signal-regulated kinase 1/2 (p-ERK1/2 )expression [(0.63 ± 0.06)vs. (0.37± 0.04)]in combined treatment group,P <0.05,<0.01. Fluorescence quantitative PCR indicated that medication can significantly reduce nicotinamide adenine dinucleotide phosphate (NADPH)oxidase subunit p47phox mRNA ex-pression (P <0.01 all),especially in combined treatment group (P =0.001).Conclusion:Combined use of telmis-artan and pyridoxamine is superior to the single use of either drug on improving thoracic aortic remodeling in SHR, the mechanism may be related to it reduces local expression of RAGE and p-ERK1/2 ,and inhibits oxidase subunit p47 of NADPH.

Objective To investigate the effects and the mechanism of telmisartan and pyridoxamine on oxidative stress in spontaneously hypertensive rats(SHR).Methods SHRs(male,20 weeks of age) were randomly divided into four groups (n＝ 12 for each):hypertension control (HC) group (2 ml of distilled water),telmisartan group[T,6 mg/(kg · d)],pyridoxamine group[P,200 mg/(kg · d)]and combined group(TP,6 mg/kg telmisartan and 200 mg/kg pyridoxamine per day).Treatments were continued for 16 weeks.The normal control group included 13 WKY rats and received gastric lavage with distilled water.SBP of tail artery was measured during the intervention ervey 2 weeks.The levels of AGEs,SOD and MDA were measured by ELISA,xanthine oxidase and thiobarbituric acid methods after the intervention.Expressiones of NF-κBp65,ERK1 and ERK2 in renal tissue were detected by immunohistochemistry.Expression of RAGE in the renal cortex was investigated by Western blot.Results SOD activity was decreased in the HC group.The levels of AGEs,MDA,RAGE and the activations of NF-κBp65 and ERK1/2 were increased in the HC group (t＝4.53,5.52,2.93,al1 P＜0.05).After the 16 weeks' intervention,SOD activity was elevated in T,P and TP groups compared to that in HC group (P＜0.05).The positive expressiones of NF-κBp65,ERK1 and ERK2 were significantly reduced in T,P and TP groups compared to those in HC group (F＝20.13、148.82、18.70,all P＜0.05).All the positive expressiones of NF-κBp65,ERK 1and ERK2 were lowest in the TP group versus T and P groups (t ＝ 3.58、2.84,P ＜ 0.05).Conclusions Telmisartan and pyridoxamine can alleviate the oxidative stress in spontaneously hypertensive rats,which may result from the blocking effect of Ang Ⅱ,the reduction of AGEs-RAGE and inhibiting the signal pathways of ROS,NF-κBp65 and ROS-ERK1/2.

Objective To establish a dot blot hybridization technique for rapid detection of staphylococci and methicillin-resistant staphylococci.Methods Three pairs of primers were designed according to nuc gene of staphylococcus aureus,mecA gene of methicillin-resistance,tuf gene of staphylococci.Specific DNA probes were synthesized by polymerase chain reaction and labeled with biotin.The bacterial DNA inoculated on nitrocellulose filter was hybridized with these probes.The sensitivity and specificity were detected.Results The DNA probes with 270bp,310bp and 370bp were amplified by the three pairs of primers respectively.The probes were specific.Among 50 clinical isolates of staphylococcus aureus tuf and nuc gene were all positive and mecA gene in 22 isolates were positive.Positive rate of tuf,nuc and mecA gene in 30 staphylococcus epidermidis were 100%,0 and 30% (9/30) respectively.No hybridization in other non-staphylococci occurred.The established method could detect as low as 1ng of bacterial DNA.Conclusion The dot blot hybridization is of high value in rapid,effective identification of methicillin-resistant staphylococci.

Objective To explore the ill experience of patients with deep vein thrombosis (DVT),and supply reference for making corresponding intervention.Methods The qualitative phenomenological study method was adopted in this study.Self-structured in-depth interviews were conducted with 12 patients with deep vein thrombosis and data were collected for analysis.Results After repeated refinement of the collected data,the early ill experience of deep vein thrombosis could be extracted as 4 topics.Conclusions According to the ill experience of patients with DVT,nurses can provide targeted intervention for such diseases to instruct clients to rehabilitate rapidly and improve the patients' quality of life.

AIM: To investigate the effects of adenovirus-mediated human tissue kallikerin (Ad-hKLK1) gene delivery on the proliferation, migration of VSMC_(SHR) induced by platelet derived growth factor-BB (PDGF-BB). METHODS: The VSMC_(SHR) proliferation induced by PDGF-BB was accessed by cell counting and methyl thiazolyl tetrazoliuin (MTT). The migration was assessed by modified Boyden chamber assay. Western blotting was used to determine the expressions of the cycle-independent kinase inhibitors p27~(Kip1) and p21~(Cip1).RESULTS: Proliferation of VSMC_(SHR) induced by PDGF-BB was inhibited after transfection of Ad-hKLK1 (20-100 MOI) in a MOI-dependent manner. The peak inhibition titer of Ad-hKLK1 fell on 100 MOI, with the peak inhibition rate of 39.3% (cell counting, n=3, P<0.01), 30.2% (MTT, n=3, P<0.01), peak stunning rate of cell-cycle in phase G0/G1 at 36.4%. The inhibitory effects of proliferation and cell-cycle caused by hKLK1 gene delivery were significantly abolished by Hoe140, a bradykinin B2 receptor antagonist. Migration of VSMC_(SHR) induced by PDGF-BB was inhibited after hKLK1 gene delivery, with the peak inhibitory rate of 34.6% (n=6, P<0.01). However the inhibitory effects of migration were not blocked by Hoe140. The protein expression of p27~(Kip1) and p21~(Cip1) increased significantly after the hKLK1 gene delivery, whereas Hoe140 nearly completely blocked these effects (n=3, P<0.01, respectively).CONCLUSION: The hKLK1 gene delivery may inhibit the proliferation and migration of VSMC_(SHR) induced by PDGF-BB. Bradykinin B2 receptor probably mediates the up-regulating expression of p27~(Kip1) and p21~(Cip1) that contributes to the inhibitory effects of proliferation of hKLK1. However, the inhibitory effects of migration by hKLK1 gene delivery may not be mediated by bradykinin B2 receptor.

Humanin (HN, its analogue [Gly14]-Humanin, HNG) was originally identified as an endogenous peptide that protects neuronal cells from apoptosis induced by various types of Alzheimer's disease-related insults. But the relative low content of this peptide in its natural sources limits its further characterization. An expression vector pET32a/HNG was corstructed and transformed it into E. coli BL21 trxB (DE3). HNG was expressed as a fusion protein in the soluble fraction and was purified by nickel affinity chromatography. Subsequently, the purified fusion protein was cleaved by enterokinase and was further purified by reverse-phase HPLC. A 23 mg recombinant HNG (rHNG) from 1 L bacterial culture was purified. The molecular weight of rHNG determined by ESI-MS was 2876.5 Da which was the expected size for correctly processed peptide. The N-terminal amino acid sequence of rHNG determined by Edman degradation method is identical to the theoretical sequence. Neuroprotective bioassay studies of rHNG exhibited its potential neuroprotective effect comparable to that of the natural HNG peptide.

Background Resveratrol has been unanimously recognized as an cardiovascular protective substance in red wine. It has been speculated that the anti-atherosclerosis effect of resveratrol is ascribed to its powerful anti-inflammatory effect. Objective To investigate the effects of resveratrol on injured human umbilical veno-endothelial cells (HUVEC) and the reactive oxygen species(ROS) production induced by TNF-? or soluble CD40L (sCD40L). Methods Cultured HUVEC were pre-incubated with resveratrol(1-50 ?mol/L) for 2 hours and then treated with TNF-?(10 ?g/L) or sCD40L?(10 ?g/L) for another 4 hours. MTT assay was used to detect proliterative activity of HUVEC. Immunofluorescence microscopy was used for determination of ROS expression. Results Both TNF-? and sCD40L impaired HUVEC proliferation (-32.7% and -26% vs control,P

Objective To explore the effect of resveratrol on the expression of matrix metalloproteinases-9 (MMP-9) in soluble CD40 ligand (sCD40L)-activated macrophages. Methods Human monocytic cell line THP-1 cells under an inducing of phorbol ester differentiated into macrophages. Then the macrophages were sitimulated by sCD40L independently and after a preincubation with resveratrol. The mRNA expression of MMP-9 and tissue-inhibitor of metalloproteinase-1 (TIMP-1) in macrophages were investigated by semiquantitative RT-PCR. The secretions of MMP-9 and TIMP-1 protein were measured by Western blot. The MMP-9 activity was analyzed by gelatin zymography technique. Results The expressions of MMP-9 gene(1.53±0.04 vs. 0.75±0.01,P＜0.05) and protein(244 930.8±31 268.6 vs. 192 976.8±20 223.1,P＜0.05)were higher in macrophages when stimulated by sCD40L. Resveratrol (10 μmol/L and 50 μmol/L)can inhibit the CD40L-induced gene expression and the protein secretion of MMP-9 (P＜0.01). The activity of MMP-9 was degraded by resveratrol (P＜0.05). Meanwhile resveratrol could increase the gene expression and protein secretion of TIMP-1 (P＜0.05). Conclusions Resveratrol can inhibit the CD40L-activated macrophage expression of MMP-9. It may be one of its mechanisms on antiatherosclerosis and stabilization of atheromatous plaques.

ObjectiveTo investigate the effect of resveratrol on the expressions of E-selectin and monocyte chemoattractant protein-1 (MCP-1) in activated endothelial cells.Methods After being pretreated with resveratrol followed by tumor necrosis factor-α (TNF-α) stimulation, human umbilical vein endothelial cells (HUVEC) were randomly divided into three groups: TNF group,resveratrol+TNF-α group and control group. The expression of E-selectin molecule on the surface of HUVEC was detected by flow cytometric analysis and the mRNA expressions of E-selectin and MCP -1 were determined by semiquantitative RT-PCR. ResultsTNF-α induced the expression of E-selectin and MCP-I of HUVEC.Resveratrol (10 μmol/L) inhibited E-selectin expression.The positive cells of E-selectin in TNF group, resveratrol + TNF-α group and control group were(47.84±3.2)%, (15.3±1.7)% and (3.74±1.6)%, respectively, and the differences among the three groups were statistically significant (P<0.05). Conclusions Resveratrol may contribute to the anti-atherosclerotic effect by inhibiting the expression of E-seleetin and MCP-1 of HUVEC.