Acidic deposition,which is mainly caused by atmospheric pollution,is one of the global environmental problems.Thinning is an effective management to improve the tree productivity,reduce the wildfire risk and maintain ...Acidic deposition,which is mainly caused by atmospheric pollution,is one of the global environmental problems.Thinning is an effective management to improve the tree productivity,reduce the wildfire risk and maintain a healthy forest.Since thinning may reduce the effect of acidic deposition,the effect of thinning on acidic deposition was estimated.The biomass,soil properties,pH value of runoff and groundwater in both unthinned and thinned Chinese fir plantations were measured and compared over a 5-year period(2-6 years after thinning).The results indicated that acidic deposition in the Huitong State Ecosystem Research Station was serious,and it got worse with time.Forest thinning resulted in a huge change in biomass and soil properties.During the 5-year monitoring period,biomasses of understory and litter,plant species richness,coverage of undergrowth plant layer were significantly higher in thinned site than in unthinned site.Moreover,higher soil fertility as well as lower amounts of runoff and groundwater were found in thinned site.It was suggested that thinning could improve the structure of forest,leading to restoring the effluent(runoff and groundwater) pH to the normal value.展开更多
OBJECTIVE Here we investigated the effects and the underlying mechanism of Ginkgolide K(1,10-dihydroxy-3,14-didehydroginkgolide,GK)on cardiac ER stress.METHODS Cell death,apoptosis,and ER stressrelated signalling path...OBJECTIVE Here we investigated the effects and the underlying mechanism of Ginkgolide K(1,10-dihydroxy-3,14-didehydroginkgolide,GK)on cardiac ER stress.METHODS Cell death,apoptosis,and ER stressrelated signalling pathwayswere measuredin cultured neonatal rat cardiomyocytes(NRCMs),treated with the ER stress inducers tunicamycin,hydrogen peroxide,and thapsigargin.Acute myocardial infarction was established using left coronary artery occlusion in mice,and infarct size was measured by triphenyltetrazolium chloride(TTC)staining.Echocardiography was used to assess heart function and transmission electron microscopy for evaluating ER expansion.RESULTS GK significantly decreased ER stress-induced cell death in both in vitro and in vivomodels.In ischemic injured mice,GK treatment reduced infarct size,rescued heart dysfunction and ameliorated ER dilation.Mechanistic studies revealed that the beneficial effects of GK occur through enhancement of inositol-requiring enzyme 1α(IRE1α)/X box-binding protein-1(XBP1)activity,which in turn leads to increased ER-associated degradation(ERAD)-mediated clearance of misfolded proteins and autophagy.In addition,GK is also able to partially repress the pro-apoptotic action of regulated IRE1-dependent decay(RIDD)and JNK pathway.CONCLUSION GK acts through selective activation of the IRE1α/XBP1 pathway to limit ER stress injury.GK is revealed as a promising therapeutic agent to ameliorate ER stress for treating cardiovascular diseases.展开更多
基金Project(41271332)supported by the National Natural Science Foundation of ChinaProject(11JJ2031)supported by the Natural Science Foundation of Hunan Province,China
文摘Acidic deposition,which is mainly caused by atmospheric pollution,is one of the global environmental problems.Thinning is an effective management to improve the tree productivity,reduce the wildfire risk and maintain a healthy forest.Since thinning may reduce the effect of acidic deposition,the effect of thinning on acidic deposition was estimated.The biomass,soil properties,pH value of runoff and groundwater in both unthinned and thinned Chinese fir plantations were measured and compared over a 5-year period(2-6 years after thinning).The results indicated that acidic deposition in the Huitong State Ecosystem Research Station was serious,and it got worse with time.Forest thinning resulted in a huge change in biomass and soil properties.During the 5-year monitoring period,biomasses of understory and litter,plant species richness,coverage of undergrowth plant layer were significantly higher in thinned site than in unthinned site.Moreover,higher soil fertility as well as lower amounts of runoff and groundwater were found in thinned site.It was suggested that thinning could improve the structure of forest,leading to restoring the effluent(runoff and groundwater) pH to the normal value.
文摘OBJECTIVE Here we investigated the effects and the underlying mechanism of Ginkgolide K(1,10-dihydroxy-3,14-didehydroginkgolide,GK)on cardiac ER stress.METHODS Cell death,apoptosis,and ER stressrelated signalling pathwayswere measuredin cultured neonatal rat cardiomyocytes(NRCMs),treated with the ER stress inducers tunicamycin,hydrogen peroxide,and thapsigargin.Acute myocardial infarction was established using left coronary artery occlusion in mice,and infarct size was measured by triphenyltetrazolium chloride(TTC)staining.Echocardiography was used to assess heart function and transmission electron microscopy for evaluating ER expansion.RESULTS GK significantly decreased ER stress-induced cell death in both in vitro and in vivomodels.In ischemic injured mice,GK treatment reduced infarct size,rescued heart dysfunction and ameliorated ER dilation.Mechanistic studies revealed that the beneficial effects of GK occur through enhancement of inositol-requiring enzyme 1α(IRE1α)/X box-binding protein-1(XBP1)activity,which in turn leads to increased ER-associated degradation(ERAD)-mediated clearance of misfolded proteins and autophagy.In addition,GK is also able to partially repress the pro-apoptotic action of regulated IRE1-dependent decay(RIDD)and JNK pathway.CONCLUSION GK acts through selective activation of the IRE1α/XBP1 pathway to limit ER stress injury.GK is revealed as a promising therapeutic agent to ameliorate ER stress for treating cardiovascular diseases.
