AIM: To compare Institut Georges Lopez(IGL-1) and Celsior preservation solutions for hepatic endothelium relaxation and liver cold ischemia reperfusion injury(IRI).METHODS: Two experimental models were used.In the fir...AIM: To compare Institut Georges Lopez(IGL-1) and Celsior preservation solutions for hepatic endothelium relaxation and liver cold ischemia reperfusion injury(IRI).METHODS: Two experimental models were used.In the first one, acetylcholine-induced endotheliumdependent relaxation(EDR) was measured in isolated ring preparations of rat hepatic arteries preserved or not in IGL-1 or Celsior solutions(24 h at 4 ℃).To determine nitric oxide(NO) and cyclooxygenase EDR, hepatic arteries were incubated with L-NG-nitroarginine methyl ester(L-NAME), an inhibitor of endothelium nitric oxide synthase(e NOS), or with L-NAME plus indomethacin, an inhibitor of cyclooxygenase.In the second experiment, rat livers were cold-stored in IGL-1 or Celsior solutions for 24 h at 4 ℃ and then perfused "ex vivo " for 2 h at 37 ℃.Liver injury was assessed by transaminase measurements, liver function by bile production and bromosulfophthalein clearance, oxidative stress by malondialdehyde levels and catalase activity and alterations in cell signaling pathways by pA kt, pA MPK, eN OS and MAPKs proteins level.RESULTS: After cold storage for 24 h with either Celsior or IGL-1, EDR was only slightly altered.Infreshly isolated arteries, EDR was exclusively mediated by NO.However, cold-stored arteries showed NOand COX-dependent relaxation.The decrease in NO-dependent relaxation after cold storage was significantly more marked with Celsior.The second study indicated that IGL-1 solution obtained better liver preservation and protection against IRI than Celsior.Liver injury was reduced, function was improved and there was less oxidative stress.IGL-1 solution activated Akt and AMPK, which was concomitant with increased eN OS expression and nitrite/nitrate levels.Furthermore, MAPKs kinases were regulated in livers preserved with IGL-1 solution since reductions in p-p38, p-ERK and p-JNK protein levels were observed.CONCLUSION: IGL-1 solution preserved NO-dependent relaxation better than Celsior storage solution and enhanced liver graft preservation.展开更多
AIM To compare liver proteolysis and proteasome activation in steatotic liver grafts conserved in University of Wisconsin(UW) and Institut Georges Lopez-1(IGL-1)solutions.METHODS Fatty liver grafts from male obese Z&#...AIM To compare liver proteolysis and proteasome activation in steatotic liver grafts conserved in University of Wisconsin(UW) and Institut Georges Lopez-1(IGL-1)solutions.METHODS Fatty liver grafts from male obese Zücker rats were conserved in UW and IGL-1 solutions for 24 h at 4 ℃and subjected to "ex vivo " normo-thermic perfusion(2 h; 37 ℃). Liver proteolysis in tissue specimens and perfusate was measured by reverse-phase high performance liquid chromatography. Total free amino acid release was correlated with the activation of the ubiquitin proteasome system(UPS: measured as chymotryptic-like activity and 20 S and 19 S proteasome), the prevention of liver injury(transaminases), mitochondrial injury(confocal microscopy) and inflammation markers(TNF 1 alpha, high mobility group box-1(HGMB-1) and PPAR gamma), and liver apoptosis(TUNEL assay, cytochrome c and caspase 3).RESULTS Profiles of free AA(alanine, proline, leucine, isoleucine, methionine, lysine, ornithine, and threonine, among others) were similar for tissue and reperfusion effluent. In all cases, the IGL-1 solution showed a significantly higher prevention of proteolysis than UW(P < 0.05) after cold ischemia reperfusion. Livers conserved in IGL-1 presented more effective prevention of ATP-breakdown and more inhibition of UPS activity(measured as chymotryptic-like activity). In addition, the prevention of liver proteolysis and UPS activation correlated with the prevention of liver injury(AST/ALT) and mitochondrial damage(revealed by confocal microscopy findings) as well as with the prevention of inflammatory markers(TNF1alpha and HMGB) after reperfusion. In addition, the liver grafts preserved in IGL-1 showed a significant decrease in liver apoptosis, as shown by TUNEL assay and the reduction of cytochrome c, caspase 3 and P62 levels. CONCLUSION Our comparison of these two preservation solutions suggests that IGL-1 helps to prevent ATP breakdown more effectively than UW and subsequently achieves a higher UPS inhibition and reduced liver proteolysis.展开更多
The assessment of Eastern Georges Bank cod with the assumption of a constant natural mortality of 0.2 has over-estimated stock productivity, resulting in a severe retrospective pattern since the late 2000 s. Comparing...The assessment of Eastern Georges Bank cod with the assumption of a constant natural mortality of 0.2 has over-estimated stock productivity, resulting in a severe retrospective pattern since the late 2000 s. Comparing relative exploitation rate(ratio of fishery catch at age to survey abundance indices at age) with total mortality calculated from the age distribution in surveys indicated a conflict when constant natural mortality was assumed. This inconsistency implies an increase in natural mortality since the mid-1990 s. In this paper, natural mortality estimated by Virtual Population Analysis(VPA) indicated that natural mortality for this stock has increased to 0.8 since the mid-1990 s for ages 6+. Potential factors contributing to this elevated natural mortality, including poor fish conditions and increased losses due to seal predation were discussed.展开更多
正When it comes to Cubism, one thinks of Picasso. But he was not the only founding father of Cubism. Georges Braque was the other equally important one. Georges Braque (1882-1963) was a French artist, one of the great...正When it comes to Cubism, one thinks of Picasso. But he was not the only founding father of Cubism. Georges Braque was the other equally important one. Georges Braque (1882-1963) was a French artist, one of the greatest in the 20th century. Perhaps for the Chinese, he is far less famous than Picasso, but his art style has a great influence on the successors.展开更多
George Lakoff的语言理论发展经历了几次重要的转向,从对转换生成语法的热心支持到提出生成语义学,最后发展到认知语义学.我们认为,这些转向不是偶然的,对句法和语义关系做出合理解释的理想和外部学术环境的影响是促使Lakoff理论创新的...George Lakoff的语言理论发展经历了几次重要的转向,从对转换生成语法的热心支持到提出生成语义学,最后发展到认知语义学.我们认为,这些转向不是偶然的,对句法和语义关系做出合理解释的理想和外部学术环境的影响是促使Lakoff理论创新的动因.认知语义学作为对标准理论和生成语义学的最新发展,其理论优势在于它对语义现象的研究更符合语言实际和人类心智的规律.展开更多
George Eliot is a great authoress in the Victorian age. She has made great contribution in many fields such as: philoso phy, literature and humanism. However she is a controversial novelist as well not only because he...George Eliot is a great authoress in the Victorian age. She has made great contribution in many fields such as: philoso phy, literature and humanism. However she is a controversial novelist as well not only because her life experience which revolts against the traditional way of life at that time but also her unique humanistic and feminist view. The purpose of the study is to get the panoramic view of George Eliot.展开更多
基金Supported by Tunisian Ministry of Higher Education and Scientific Research,No.UR12ES11
文摘AIM: To compare Institut Georges Lopez(IGL-1) and Celsior preservation solutions for hepatic endothelium relaxation and liver cold ischemia reperfusion injury(IRI).METHODS: Two experimental models were used.In the first one, acetylcholine-induced endotheliumdependent relaxation(EDR) was measured in isolated ring preparations of rat hepatic arteries preserved or not in IGL-1 or Celsior solutions(24 h at 4 ℃).To determine nitric oxide(NO) and cyclooxygenase EDR, hepatic arteries were incubated with L-NG-nitroarginine methyl ester(L-NAME), an inhibitor of endothelium nitric oxide synthase(e NOS), or with L-NAME plus indomethacin, an inhibitor of cyclooxygenase.In the second experiment, rat livers were cold-stored in IGL-1 or Celsior solutions for 24 h at 4 ℃ and then perfused "ex vivo " for 2 h at 37 ℃.Liver injury was assessed by transaminase measurements, liver function by bile production and bromosulfophthalein clearance, oxidative stress by malondialdehyde levels and catalase activity and alterations in cell signaling pathways by pA kt, pA MPK, eN OS and MAPKs proteins level.RESULTS: After cold storage for 24 h with either Celsior or IGL-1, EDR was only slightly altered.Infreshly isolated arteries, EDR was exclusively mediated by NO.However, cold-stored arteries showed NOand COX-dependent relaxation.The decrease in NO-dependent relaxation after cold storage was significantly more marked with Celsior.The second study indicated that IGL-1 solution obtained better liver preservation and protection against IRI than Celsior.Liver injury was reduced, function was improved and there was less oxidative stress.IGL-1 solution activated Akt and AMPK, which was concomitant with increased eN OS expression and nitrite/nitrate levels.Furthermore, MAPKs kinases were regulated in livers preserved with IGL-1 solution since reductions in p-p38, p-ERK and p-JNK protein levels were observed.CONCLUSION: IGL-1 solution preserved NO-dependent relaxation better than Celsior storage solution and enhanced liver graft preservation.
基金Supported by Instituto de Salud Carlos III(ISCIII)through the FIS project PI12/0056,co-funded by FEDER from Regional Development European Funds(European Union)
文摘AIM To compare liver proteolysis and proteasome activation in steatotic liver grafts conserved in University of Wisconsin(UW) and Institut Georges Lopez-1(IGL-1)solutions.METHODS Fatty liver grafts from male obese Zücker rats were conserved in UW and IGL-1 solutions for 24 h at 4 ℃and subjected to "ex vivo " normo-thermic perfusion(2 h; 37 ℃). Liver proteolysis in tissue specimens and perfusate was measured by reverse-phase high performance liquid chromatography. Total free amino acid release was correlated with the activation of the ubiquitin proteasome system(UPS: measured as chymotryptic-like activity and 20 S and 19 S proteasome), the prevention of liver injury(transaminases), mitochondrial injury(confocal microscopy) and inflammation markers(TNF 1 alpha, high mobility group box-1(HGMB-1) and PPAR gamma), and liver apoptosis(TUNEL assay, cytochrome c and caspase 3).RESULTS Profiles of free AA(alanine, proline, leucine, isoleucine, methionine, lysine, ornithine, and threonine, among others) were similar for tissue and reperfusion effluent. In all cases, the IGL-1 solution showed a significantly higher prevention of proteolysis than UW(P < 0.05) after cold ischemia reperfusion. Livers conserved in IGL-1 presented more effective prevention of ATP-breakdown and more inhibition of UPS activity(measured as chymotryptic-like activity). In addition, the prevention of liver proteolysis and UPS activation correlated with the prevention of liver injury(AST/ALT) and mitochondrial damage(revealed by confocal microscopy findings) as well as with the prevention of inflammatory markers(TNF1alpha and HMGB) after reperfusion. In addition, the liver grafts preserved in IGL-1 showed a significant decrease in liver apoptosis, as shown by TUNEL assay and the reduction of cytochrome c, caspase 3 and P62 levels. CONCLUSION Our comparison of these two preservation solutions suggests that IGL-1 helps to prevent ATP breakdown more effectively than UW and subsequently achieves a higher UPS inhibition and reduced liver proteolysis.
文摘The assessment of Eastern Georges Bank cod with the assumption of a constant natural mortality of 0.2 has over-estimated stock productivity, resulting in a severe retrospective pattern since the late 2000 s. Comparing relative exploitation rate(ratio of fishery catch at age to survey abundance indices at age) with total mortality calculated from the age distribution in surveys indicated a conflict when constant natural mortality was assumed. This inconsistency implies an increase in natural mortality since the mid-1990 s. In this paper, natural mortality estimated by Virtual Population Analysis(VPA) indicated that natural mortality for this stock has increased to 0.8 since the mid-1990 s for ages 6+. Potential factors contributing to this elevated natural mortality, including poor fish conditions and increased losses due to seal predation were discussed.
文摘正When it comes to Cubism, one thinks of Picasso. But he was not the only founding father of Cubism. Georges Braque was the other equally important one. Georges Braque (1882-1963) was a French artist, one of the greatest in the 20th century. Perhaps for the Chinese, he is far less famous than Picasso, but his art style has a great influence on the successors.
文摘George Eliot is a great authoress in the Victorian age. She has made great contribution in many fields such as: philoso phy, literature and humanism. However she is a controversial novelist as well not only because her life experience which revolts against the traditional way of life at that time but also her unique humanistic and feminist view. The purpose of the study is to get the panoramic view of George Eliot.
