Objective This study aimed to assess the protective value of adiponectin(APN)in pancreatic islet injury induced by chronic intermittent hypoxia(CIH).Methods Sixty rats were randomly divided into three groups:normal co...Objective This study aimed to assess the protective value of adiponectin(APN)in pancreatic islet injury induced by chronic intermittent hypoxia(CIH).Methods Sixty rats were randomly divided into three groups:normal control(NC)group,CIH group,and CIH with APN supplement(CIH+APN)group.After 5 weeks of CIH exposure,we conducted oral glucose tolerance tests(OGTT)and insulin released test(IRT),examined and compared the adenosine triphosphate(ATP)levels,mitochondrial membrane potential(MMP)levels,reactive oxygen species(ROS)levels,enzymes gene expression levels of Ant1,Cs,Hmox1,and Cox4 i1 which represented mitochondrial tricarboxylic acid cycle function,the protein and gene expression levels of DRP1,FIS1,MFN1,and OPA1 which represented mitochondrial fusion and division,and the protein expression levels of BAX,BCL-2,cleaved Caspase-3,and cleaved PARP which represented mitochondrial associated apoptosis pathway of pancreatic islet.Results OGTT and IRT showed blood glucose and insulin levels had no differences among the NC,CIH and CIH+APN groups(both P>0.05)at 0 min,20 min,30 min,60 min,120 min.However,we found that compared to NC group,CIH increased the ROS level,reduced ATP level and MMP level.The islets of CIH exposed rats showed reduced gene expression levels of Ant1,Cs,Hmox1,and Cox4 i1,decreased protein and gene expression levels of MFN1 and OPA1,increased protein and gene expression levels of DRP1 and FIS1,increased protein expression levels of cleaved Caspase-3 and cleaved PARP,with lower ratio of BCL-2/BAX at protein expression level.All the differences among three groups were statistically significant.APN treated CIH rats showed mitigated changes in the above measurements associated with islet injuries.Conclusion APN may ameliorate the pancreatic islet injury induced by CIH via inhibiting the imbalance in mitochondrial fusion and division.展开更多
OECD/NEA （Organization for Economic Cooperation and Development/Nuclear Energy Agency） launched the SERENA （steam explosion resolution for nuclear application） project to resolve internationally the ex-vessel stea...OECD/NEA （Organization for Economic Cooperation and Development/Nuclear Energy Agency） launched the SERENA （steam explosion resolution for nuclear application） project to resolve internationally the ex-vessel steam explosion issue, which is one of major unresolved issues after a TMI-2 （three mile island-2） accident. One of main conclusions of OECD/NEA SERENA Phase 1, which was completed in 2005, was that some damage to the cavity is to be expected for an ex-vessel explosion. One major uncertainty that does not allow for a convergence toward consistent predictions was that there are no data on the component distribution in a pre-mixture at the time of an explosion, especially the level of the void. The other major uncertainty is the explosion behavior of corium melts. Therefore, SERENA Phase 2 was launched on October 1, 2007 to resolve the uncertainties of the coolant void and material effect by performing a limited number of well-designed tests with advanced instrumentation reflecting a large spectrum of ex-vessel melt compositions and conditions, and the required analytical work to bring the code capabilities to a sufficient level for use in reactor case analyses. The recent status of the OECD-SERENA Phase 2 project for the resolution of ex-vessel steam explosion risks will be described.展开更多
Participatory and integrated research approaches employed by a long-term Thai- Vietnamese-German collaborative research program, ‘The Uplands Program’, that address the vicious circles of resource scarcity, environm...Participatory and integrated research approaches employed by a long-term Thai- Vietnamese-German collaborative research program, ‘The Uplands Program’, that address the vicious circles of resource scarcity, environmental degrada- tion and rural poverty in mountainous regions of northern Thailand and northern Vietnam are discussed in this paper. We present two examples from the Thai component of the research program to show how different disciplines and stakeholders need to cooperate at different scales to make meaningful scientific contributions towards sustainable land use and rural development in mountainous regions. The case of resource conservation in the Thai highlands shows that local and scientific knowledge, conven- tional surveys and participatory modeling can be creatively combined. Integrated research on the potential of integrating fruit trees and associated technologies into mountain farming systems suggests that natural scientists have to work alongsideeconomists and social scientists to avoid harmful effects of purely technology-driven and productivity- enhancing approaches. The success of new technologies cannot be measured solely by adoption rates and yield increases, but also needs to take into account their long-term impact on various groups of farmers and the ecological, economic and social trade-offs that they entail. Technical and institutional innovations need to go hand in hand to provide viable livelihood opportunities for smallholder farmers in mountain watersheds. The major lesson learned from the first six years of our research in the mountains of Thailand and Vietnam is that conventional and participatory approaches are not antagonistic; if scientists from various disciplines and research paradigms are open-minded, the combination of both approaches can produce meaningful results that cater for the needs of both the academic community and local stakeholders in mountain environments.展开更多
The subgenomic mRNA transcription and genomic replication of the porcine reproductive and respiratory syndrome virus (PRRSV) are directed by the viral replicase. The replicase is expressed in the form of two polyprote...The subgenomic mRNA transcription and genomic replication of the porcine reproductive and respiratory syndrome virus (PRRSV) are directed by the viral replicase. The replicase is expressed in the form of two polyproteins and is subsequently processed into smaller nonstructural proteins (nsps). nsp9, containing the viral replicase, has characteristic sequence motifs conserved among the RNA-dependent RNA polymerases (RdRp) of positive-strand (PS) RNA viruses. To test whether the conserved SDD motif can tolerate other conserved motifs of RNA viruses and the influence of every residue on RdRp catalytic activity, many amino acids substitutions were introduced into it. Only one nsp9 substitution, of serine by glycine (S3050G), could rescue mutant viruses. The rescued virus was genetically stable. Alteration of either aspartate residue was not tolerated, destroyed the polymerase activity, and abolished virus transcription, but did not eliminate virus replication. We also found that the SDD motif was essentially invariant for the signature sequence of PRRSV RdRp. It could not accommodate other conserved motifs found in other RNA viral polymerases, except the GDD motif, which is conserved in all the other PS RNA viruses. These findings indicated that nidoviruses are evolutionarily related to other PS RNA viruses. Our studies support the idea that the two aspartate residues of the SDD motif are critical and essential for PRRSV transcription and represent a sequence variant of the GDD motif in PS RNA viruses.展开更多
文摘Objective This study aimed to assess the protective value of adiponectin(APN)in pancreatic islet injury induced by chronic intermittent hypoxia(CIH).Methods Sixty rats were randomly divided into three groups:normal control(NC)group,CIH group,and CIH with APN supplement(CIH+APN)group.After 5 weeks of CIH exposure,we conducted oral glucose tolerance tests(OGTT)and insulin released test(IRT),examined and compared the adenosine triphosphate(ATP)levels,mitochondrial membrane potential(MMP)levels,reactive oxygen species(ROS)levels,enzymes gene expression levels of Ant1,Cs,Hmox1,and Cox4 i1 which represented mitochondrial tricarboxylic acid cycle function,the protein and gene expression levels of DRP1,FIS1,MFN1,and OPA1 which represented mitochondrial fusion and division,and the protein expression levels of BAX,BCL-2,cleaved Caspase-3,and cleaved PARP which represented mitochondrial associated apoptosis pathway of pancreatic islet.Results OGTT and IRT showed blood glucose and insulin levels had no differences among the NC,CIH and CIH+APN groups(both P>0.05)at 0 min,20 min,30 min,60 min,120 min.However,we found that compared to NC group,CIH increased the ROS level,reduced ATP level and MMP level.The islets of CIH exposed rats showed reduced gene expression levels of Ant1,Cs,Hmox1,and Cox4 i1,decreased protein and gene expression levels of MFN1 and OPA1,increased protein and gene expression levels of DRP1 and FIS1,increased protein expression levels of cleaved Caspase-3 and cleaved PARP,with lower ratio of BCL-2/BAX at protein expression level.All the differences among three groups were statistically significant.APN treated CIH rats showed mitigated changes in the above measurements associated with islet injuries.Conclusion APN may ameliorate the pancreatic islet injury induced by CIH via inhibiting the imbalance in mitochondrial fusion and division.
文摘OECD/NEA （Organization for Economic Cooperation and Development/Nuclear Energy Agency） launched the SERENA （steam explosion resolution for nuclear application） project to resolve internationally the ex-vessel steam explosion issue, which is one of major unresolved issues after a TMI-2 （three mile island-2） accident. One of main conclusions of OECD/NEA SERENA Phase 1, which was completed in 2005, was that some damage to the cavity is to be expected for an ex-vessel explosion. One major uncertainty that does not allow for a convergence toward consistent predictions was that there are no data on the component distribution in a pre-mixture at the time of an explosion, especially the level of the void. The other major uncertainty is the explosion behavior of corium melts. Therefore, SERENA Phase 2 was launched on October 1, 2007 to resolve the uncertainties of the coolant void and material effect by performing a limited number of well-designed tests with advanced instrumentation reflecting a large spectrum of ex-vessel melt compositions and conditions, and the required analytical work to bring the code capabilities to a sufficient level for use in reactor case analyses. The recent status of the OECD-SERENA Phase 2 project for the resolution of ex-vessel steam explosion risks will be described.
文摘Participatory and integrated research approaches employed by a long-term Thai- Vietnamese-German collaborative research program, ‘The Uplands Program’, that address the vicious circles of resource scarcity, environmental degrada- tion and rural poverty in mountainous regions of northern Thailand and northern Vietnam are discussed in this paper. We present two examples from the Thai component of the research program to show how different disciplines and stakeholders need to cooperate at different scales to make meaningful scientific contributions towards sustainable land use and rural development in mountainous regions. The case of resource conservation in the Thai highlands shows that local and scientific knowledge, conven- tional surveys and participatory modeling can be creatively combined. Integrated research on the potential of integrating fruit trees and associated technologies into mountain farming systems suggests that natural scientists have to work alongsideeconomists and social scientists to avoid harmful effects of purely technology-driven and productivity- enhancing approaches. The success of new technologies cannot be measured solely by adoption rates and yield increases, but also needs to take into account their long-term impact on various groups of farmers and the ecological, economic and social trade-offs that they entail. Technical and institutional innovations need to go hand in hand to provide viable livelihood opportunities for smallholder farmers in mountain watersheds. The major lesson learned from the first six years of our research in the mountains of Thailand and Vietnam is that conventional and participatory approaches are not antagonistic; if scientists from various disciplines and research paradigms are open-minded, the combination of both approaches can produce meaningful results that cater for the needs of both the academic community and local stakeholders in mountain environments.
基金supported by the National Natural Science Foundation of China (Grant Nos. 30972204 and 30901078)the EU Frame 7 Project (Grant No. 245141)the Shanghai Municipal Science and Technology Special Programs (Grant No. 08ZR1422800) to Yuan ShiShan
文摘The subgenomic mRNA transcription and genomic replication of the porcine reproductive and respiratory syndrome virus (PRRSV) are directed by the viral replicase. The replicase is expressed in the form of two polyproteins and is subsequently processed into smaller nonstructural proteins (nsps). nsp9, containing the viral replicase, has characteristic sequence motifs conserved among the RNA-dependent RNA polymerases (RdRp) of positive-strand (PS) RNA viruses. To test whether the conserved SDD motif can tolerate other conserved motifs of RNA viruses and the influence of every residue on RdRp catalytic activity, many amino acids substitutions were introduced into it. Only one nsp9 substitution, of serine by glycine (S3050G), could rescue mutant viruses. The rescued virus was genetically stable. Alteration of either aspartate residue was not tolerated, destroyed the polymerase activity, and abolished virus transcription, but did not eliminate virus replication. We also found that the SDD motif was essentially invariant for the signature sequence of PRRSV RdRp. It could not accommodate other conserved motifs found in other RNA viral polymerases, except the GDD motif, which is conserved in all the other PS RNA viruses. These findings indicated that nidoviruses are evolutionarily related to other PS RNA viruses. Our studies support the idea that the two aspartate residues of the SDD motif are critical and essential for PRRSV transcription and represent a sequence variant of the GDD motif in PS RNA viruses.
