AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A contr...AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A control group received the vehicle by gavage. Rebamipide (100 mg/kg, 200 mg/kg, 400 mg/kg) was administered intragastrically once a day for 3 d 4 h after diclofenac administration. Intestinal permeability was evaluated by Evans blue and the FITC-dextran method. The ultrastructure of the mucosal barrier was evaluated by transmission electron microscopy (TEM). Mitochondrial function including mitochondrial swelling, mitochondrial membrane potential, mitochondrial nicotinamide adenine dinucleotide-reduced (NADH) levels, succinate dehydrogenase (SDH) and ATPase activities were measured. Small intestinal mucosa was collected for assessment of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity. RESULTS: Compared with the control group, intestinal permeability was significantly increased in the diclofenac group, which was accompanied by broken tight junctions, and significant increases in MDA content and MPO activity. Rebamipide significantly reduced intestinal permeability, improved inter-cellular tight junctions, and was associated with decreases in intestinal MDA content and MPO activity. At the mitochondrial level, rebamipide increased SDH and ATPase activities, NADH level and decreased mitochondrial swelling. CONCLUSION: Increased intestinal permeability induced by diclofenac can be attenuated by rebamipide, which partially contributed to the protection of mitochondrial function.展开更多
The activity of two Cu/SiO2 catalysts prepared by the chemisorption hydrolysis technique has been tested in the hydrogenation reaction of 3-methyl-cyclohexanone. Both catalysts were found to be very active at 60 ℃ an...The activity of two Cu/SiO2 catalysts prepared by the chemisorption hydrolysis technique has been tested in the hydrogenation reaction of 3-methyl-cyclohexanone. Both catalysts were found to be very active at 60 ℃ and 1 atm of H2. Characterization of the materials by FT-IR of adsorbed CO and TEM put in light the presence of well formed Cu cristallites. By assuming a cuboctahedral model we could show that the hydrogenation activity is linked to high coordination sites on the metal particle. A comparison is also reported with a sample prepared by ammonia evaporation that was found to be inactive in the hydrogenation reaction under the same experimental conditions.展开更多
The high temperature phase a-Ba3Y(BO3)3 was synthesized by Czochralski method, and its crystal structure has been determined by single-crystal X-ray diffraction. It crystallizes in the trigonal system, space group 3R ...The high temperature phase a-Ba3Y(BO3)3 was synthesized by Czochralski method, and its crystal structure has been determined by single-crystal X-ray diffraction. It crystallizes in the trigonal system, space group 3R with a = 13.028(2), c = 9.4992(2) ? V = 1396.1(5) ?, Ba3YB3O9, Mr = 677.36, Z = 6, Dc = 4.834 g/cm3, l(MoKa) = 0.71073 ? m = 18.721 mm-1, F(000) = 1764, the final R = 0.0718 and wR = 0.1640 for 1199 observed reflections with I > 2s(I). In this structure two alternate nonequivalent Y atoms form one-dimensional chains bridged by the Ba atoms with BO3 triangles which link Y(1) and Y(2), respectively. The Ba atom is surrounded by nine O atoms belonging to six BO3 triangles.展开更多
China is experiencing rapid urbanization that has changed the water quality of rivers, especially nutrient loads. In this study, a typical urban river located in a karst area, Chengguan River, was chosen to explore th...China is experiencing rapid urbanization that has changed the water quality of rivers, especially nutrient loads. In this study, a typical urban river located in a karst area, Chengguan River, was chosen to explore the influence of urbanization on river ecosystems based on nutrient concentration and nitrate isotopes. The results show monthly variability of water chemistry and nutrient concentration. Nutrient concentration in two tributaries and the mainstem showed significant spatial variability, with heavy N and P pollution in one tributary near a suburban area,indicating a response to different levels of urbanization.Measurements of nitrate dual isotopes suggest thatvolatilization, assimilation, nitrification, and denitrification all occur in the polluted river. Water chemistry and nitrate isotopes show that major nitrogen sources included domestic waste and agricultural input, such as chemical fertilizer and manure. The results suggest that urbanization increases nutrient concentrations and accelerates the riverine nitrogen dynamic, and point to the need to manage point sources of sewage effluents to improve the water quality of urban rivers in southwestern China.展开更多
Acrylate terpolymer- bound Se, N bidentate ligand was synthesized fromthe side chain chlorine of copolymer and β- dimethylamino -β - hydroxyl diethyl selenoether. The polymer - supported platinum complex exhibited h...Acrylate terpolymer- bound Se, N bidentate ligand was synthesized fromthe side chain chlorine of copolymer and β- dimethylamino -β - hydroxyl diethyl selenoether. The polymer - supported platinum complex exhibited highcatalytic activity in the hodrosilylation of olefins with triethoxysilane.展开更多
文摘AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A control group received the vehicle by gavage. Rebamipide (100 mg/kg, 200 mg/kg, 400 mg/kg) was administered intragastrically once a day for 3 d 4 h after diclofenac administration. Intestinal permeability was evaluated by Evans blue and the FITC-dextran method. The ultrastructure of the mucosal barrier was evaluated by transmission electron microscopy (TEM). Mitochondrial function including mitochondrial swelling, mitochondrial membrane potential, mitochondrial nicotinamide adenine dinucleotide-reduced (NADH) levels, succinate dehydrogenase (SDH) and ATPase activities were measured. Small intestinal mucosa was collected for assessment of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity. RESULTS: Compared with the control group, intestinal permeability was significantly increased in the diclofenac group, which was accompanied by broken tight junctions, and significant increases in MDA content and MPO activity. Rebamipide significantly reduced intestinal permeability, improved inter-cellular tight junctions, and was associated with decreases in intestinal MDA content and MPO activity. At the mitochondrial level, rebamipide increased SDH and ATPase activities, NADH level and decreased mitochondrial swelling. CONCLUSION: Increased intestinal permeability induced by diclofenac can be attenuated by rebamipide, which partially contributed to the protection of mitochondrial function.
文摘The activity of two Cu/SiO2 catalysts prepared by the chemisorption hydrolysis technique has been tested in the hydrogenation reaction of 3-methyl-cyclohexanone. Both catalysts were found to be very active at 60 ℃ and 1 atm of H2. Characterization of the materials by FT-IR of adsorbed CO and TEM put in light the presence of well formed Cu cristallites. By assuming a cuboctahedral model we could show that the hydrogenation activity is linked to high coordination sites on the metal particle. A comparison is also reported with a sample prepared by ammonia evaporation that was found to be inactive in the hydrogenation reaction under the same experimental conditions.
基金the Key Project of Science and Technology of Fujian province (2001H107) and National Natural Science Foundation of China (N0. 59972037)
文摘The high temperature phase a-Ba3Y(BO3)3 was synthesized by Czochralski method, and its crystal structure has been determined by single-crystal X-ray diffraction. It crystallizes in the trigonal system, space group 3R with a = 13.028(2), c = 9.4992(2) ? V = 1396.1(5) ?, Ba3YB3O9, Mr = 677.36, Z = 6, Dc = 4.834 g/cm3, l(MoKa) = 0.71073 ? m = 18.721 mm-1, F(000) = 1764, the final R = 0.0718 and wR = 0.1640 for 1199 observed reflections with I > 2s(I). In this structure two alternate nonequivalent Y atoms form one-dimensional chains bridged by the Ba atoms with BO3 triangles which link Y(1) and Y(2), respectively. The Ba atom is surrounded by nine O atoms belonging to six BO3 triangles.
基金financially supported by National Natural Science Foundation of China(Grant Nos.41571130072 and41130536)the Ministry of Science and Technology of China through Grant Nos.2016YFA0601000 and 2013CB956700
文摘China is experiencing rapid urbanization that has changed the water quality of rivers, especially nutrient loads. In this study, a typical urban river located in a karst area, Chengguan River, was chosen to explore the influence of urbanization on river ecosystems based on nutrient concentration and nitrate isotopes. The results show monthly variability of water chemistry and nutrient concentration. Nutrient concentration in two tributaries and the mainstem showed significant spatial variability, with heavy N and P pollution in one tributary near a suburban area,indicating a response to different levels of urbanization.Measurements of nitrate dual isotopes suggest thatvolatilization, assimilation, nitrification, and denitrification all occur in the polluted river. Water chemistry and nitrate isotopes show that major nitrogen sources included domestic waste and agricultural input, such as chemical fertilizer and manure. The results suggest that urbanization increases nutrient concentrations and accelerates the riverine nitrogen dynamic, and point to the need to manage point sources of sewage effluents to improve the water quality of urban rivers in southwestern China.
文摘Acrylate terpolymer- bound Se, N bidentate ligand was synthesized fromthe side chain chlorine of copolymer and β- dimethylamino -β - hydroxyl diethyl selenoether. The polymer - supported platinum complex exhibited highcatalytic activity in the hodrosilylation of olefins with triethoxysilane.
