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Objective:To explore the effects of human recombinant erythropoietin (rhEPO) on inflammation of hyperoxic lung injury in neonatal rats.Methods:Seventy-two neonatal rats were randomly divided into 4 groups: control group, BPD group, hyperoxia + low-dose recombinant erythropoietin [EPO(L)]group, and hyperoxia + high-dose recombinant erythropoietin [EPO(H)]group.The neonatal rats in BPD group, hyperoxia + EPO(L)group and hyperoxia + EPO(H)group were exposed to 850 mL/L oxygen.Then the neonatal rats in hyperoxia + EPO(L)group and hyperoxia + EPO(H)group were given 800 IU/kg and 2 000 IU/kg rhEPO by subcutaneous injection respectively at 1 d, 3 d and 7 d, while the control group and BPD group were given the same amount of 9 g/L saline water.Initially, the body weight of each group was recorded at 3 d, 7 d and 14 d. The morphological structure changes of lung tissues were observed by HE staining under light microscope, and the radial alveolar count(RAC) in lung tissues were detected.The expression of nuclear factor kappa B(NF-κB) was detected by immunofluorescence staining; Western blot was applied to determine the protein expression of phosphorylated NF-κB(pNF-κB), inhibitor protein(IκB) and Caspase-3 in lung tissues; and the expression of interleukin-1β(IL-1β) in bronchoalveolar lavage fluid was determined using enzyme linked immunosorbent assay (ELISA).Results:(1) On the 14 th day, the body weight of neonatal rats in the BPD group was lower than that in the control group [(18.97±3.21) g vs.(27.97±2.30) g], and the difference was statistically significant( P<0.01); however, the body weights of neonatal rats in the hyperoxia+ EPO(L)group and hyperoxia+ EPO(H)group[(24.16±2.15) g, (26.04±1.97) g] was much heavier than that in the BPD group, and the differences was statistically significant(all P<0.05). (2) The morphological structure of lung tissues which was observed by HE staining showed that in the BPD group, there were a few inflammatory cells infiltration in alveolar septum on the 3 rd day, the inflammatory response was more evident on the 7 th day, when exudation could be seen in the alveolar cavity; and on the 14 th day, the number of pulmonary alveoli decreased, pulmonary bulla formed, and septa were thickened.Besides, it was also observed that compared with control group, RAC was significantly decreased in BPD group on the 14 th day(5.50±1.29 vs.14.33±2.80), and the difference was statistically significant( P<0.01). Pathological changes were ameliorated and the infiltration of inflammatory reaction cells was reduced in the hyperoxia+ EPO(L)group and hyperoxia + EPO(H)group.RAC was remarkably higher in the hyperoxia+ EPO(L)group and hyperoxia+ EPO(H)group than that in the BPD group on the 14 th day, and the differences were statistically significant (all P<0.05). (3)Immunofluorescence results showed that: the number of NF-κB p65 positive cells increased significantly and fluorescence intensity increased in the BPD group, while EPO could greatly reduce the number of NF-κB p65 positive cells and lower the fluorescence intensity.(4)Western blot results indicated that compared with the control group, the expressions of pNF-κB p65 and Cleaved Caspase-3 was significantly increased, and the differences were statistically significant (all P<0.05); and IκB was significantly lower, and the difference was statistically significant ( P<0.05). The expression of NF-κB p65 and Cleaved Caspase-3 was significantly lower, but IκB was significantly higher in the hyperoxia+ EPO(L)group and the hyperoxia+ EPO(H)group than those in the BPD group, and the differences were statistically significant (all P<0.05). (5) ELISA results revealed that the expression of IL-1β in the BPD group was significantly higher than that in the control group, and the difference was statistically significant ( P<0.05); Compared with BPD group, the expression of IL-1β was significantly lower in the hyperoxia+ EPO(L)group and hyperoxia+ EPO(H)group, and the differences were statistically significant (all P<0.05). Conclusions:EPO can reduce hyperoxia-induced lung tissue apoptosis and protect newborn rats against hyperoxic lung injury by decreasing the inflammatory response of cells through the NF-κB pathway on BPD.
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Objective To investigate the effect of transforming growth factor β receptor-Ⅱ(TGF-βRⅡ) on AngⅡ inducing glomerular mesangial cell(GMC) proliferation and the expressions of TGF-β1 and psmad3 through transfecting TGF-βRⅡsmall interfering RNA(siRNA)into GMC. Methods Through transfecting fluo-rescence control siRNA into GMC ,we observed the transfection efficiency under fluorescence microscope after 6 hours. Transfecting TGF-βRⅡsiRNA and negative control siRNA into GMC respectively ,we detected the expres-sion of TGF-βRⅡ by western blot after 24 hours. The cells were divided into four groups:control group,AngⅡgroup,negative siRNA control group and TGF-βRⅡ siRNA group. Each group was stimulated by AngⅡ except the control group. After 24 hours,we detected the TGF-β1 and psmad3 protein levels by western blot and detected GMC proliferation by CCK8 kit. Results (1) Comparing with the scrambled control group,the expression of TGFβRⅡin the TGF-βRⅡsiRNA group was significantly decreased(P<0.05).(2)AngⅡcould accelerate the expression of TGF-β1. Transfecting TGF-βRⅡsiRNA into GMC decreased the expression of TGF-β1 protein(P<0.05).(3)AngⅡ could stimulate the phosphorylation of smad3. Transfecting TGF-βRⅡ siRNA into GMC de-creased the expression of psmad3 protein(P < 0.05).(4)Transfecting TGF-βRⅡ siRNA into GMC relieved the GMC proliferation AngⅡ-promoted(P < 0.05). Conclusions The AngⅡ stimulates the GMC proliferation,de-pending on the expression of TGF-βRⅡ. It is related to the expressions of TGF-β1 and psmad3.
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Objective To investigate the effect of applying web based problem-based learning in the teaching of bilingual curriculum.Methods 2009 grade nursing undergraduate bilingual class (n =57) was taken as control group and traditional teaching method was used.2010 grade nursing undergraduate bilingual class (n =60) was taken as experimental group and bilingual course of introduction to nursing was used to do web based (Blackboard platform) PBL teaching.Teaching process of the grouping-question posing-data gathering-discussion-mid-term feedback-presentation-summary and evaluation was implemented.Result comparison method,network based PBL learning evaluation sheet and content analysis were employed to complete teaching effect evaluation.Data were analyzed by t test and P ＜ 0.05 signifies statistically significant differences.Results Test scores of experimental group were significantly higher than that in control group (P ＜ 0.05).Mean scores of positive items in web based PBL teaching scale were ≥3.84.Electronic learning file content analysis showed that excellent rates of 7 indicators (student participation,thinking ability,inquiry,etc) were ≥66.7％.Conclusion Web based PBL teaching model is good for improving teaching effectiveness in the teaching of bilingual curriculum.
ABSTRACT
Due to the subjective and objective constraints of universities in China,PBL Teaching Mode failed to gain its popularity in China's medical education.In its teaching reform,Guangzhou Medical University put forward a new teaching model--Web-based PBL Teaching Mode(hereinafter referred to as WPBL).by integrating the classical concept of PBL education with the real situation of the university and carried it out among students in bilingual classes of Clinical Medicine.The resuIts showed that by effectively overcoming the difficulties during the implementation of classical PBL teaching,Web-based PBL Teaching Mode not only succeeded in achieving the teaching objectives,but also improved the learning efficiency and utilization of teaching resources greatly by means of network technology.