Background Diabetic macrovascular complications are important causes of cardiovascular and cerebrovascular diseases and also one of the major causes of morbidity and mortality in patients with type 2 diabetes mellitus...Background Diabetic macrovascular complications are important causes of cardiovascular and cerebrovascular diseases and also one of the major causes of morbidity and mortality in patients with type 2 diabetes mellitus （T2DM）. Phlorizin has been reported to be effective in reducing the blood glucose level in diabetic mellitus, while little is known about its effects on vascular complications. This study aimed to observe the effects of phlorizin on the aorta of diabetes db/db mice and explore its mechanism. Methods Diabetic db/db mice （n=16） and age-matched db/m mice （n=8） were divided into three groups： normal control group （CC group, db/m mice, n=8）, untreated diabetic group （DM group, db/db mice, n=8） and diabetic group treated by phlorizin （DMT group, db/db mice, n=8）. Phlorizin （20 mg/kg body weight） was given in normal saline solution intragastrically for 10 weeks. Animals were weighed weekly. At the 10th weekend, all mice were fasted overnight and then sacrificed. Fasting blood was collected, and the aortas were dissected. The blood samples were analyzed for fasting blood glucose （FBG）, serum advanced glycation end products （AGEs）, malondialdehyde （MDA） and superoxide dismutase （SOD） activity, the aortic ultrastructure was studied. Results The weight and serum concentration of FBG, AGEs, and MDA in the DM group were higher than that in the CC group （P 〈0.01 ）, and they were significantly lower in the DMT group （P 〈0.05）. Serum SOD activity was lower than that in the CC group （P 〈0.01）, and it is significantly higher in the DMT group （P 〈0.05）. The severity of aorta damage in the DMT group was less than that in the DM group. Conclusions Phlorizin protected the db/db mice from diabetic macrovascular complications, attributed to the decreasing of blood glucose and AGEs level, and its antioxidant potential. This study may provide a new natural medicine for treating diabetic macrovascular complications.展开更多
BACKGROUND Sodium glucose cotransporter-2 inhibitors(SGLT2-I)are the most recently approved drugs for type 2 diabetes(T2D).Recent clinical trials of these compounds reported beneficial cardiovascular(CV)and renal outc...BACKGROUND Sodium glucose cotransporter-2 inhibitors(SGLT2-I)are the most recently approved drugs for type 2 diabetes(T2D).Recent clinical trials of these compounds reported beneficial cardiovascular(CV)and renal outcomes.A major cause of vascular dysfunction and CV disease in diabetes is hyperglycemia associated with inflammation and oxidative stress.Pre-clinical studies demonstrated that SGLT2-I reduce glucotoxicity and promote anti-inflammatory effects by lowering oxidative stress.AIM To investigate the effects of SGLT2-I on markers of oxidative stress,inflammation,liver steatosis,and fibrosis in patients of T2D with non-alcoholic fatty liver disease(NAFLD).METHODS We referred fifty-two consecutive outpatients treated with metformin monotherapy and exhibiting poor glycemic control to our centre.We introduced the outpatients to an SGLT2-I(dapagliflozin,empagliflozin,or canagliflozin;n=26)or a different hypoglycemic drug[other glucose-lowering drugs(OTHER),n=26].We evaluated circulating interleukins and serum hydroxynonenal(HNE)-or malondialdehyde(MDA)-protein adducts,fatty liver index(FLI),NAFLD fibrosis score,aspartate aminotransferase(AST)/alanine aminotransferase(ALT)ratio,AST-to-platelet-ratio index(APRI),and fibrosis-4 on the day before(T0)and following treatment for six months(T1).We also performed transient elastography at T0 and T1.RESULTS Add-on therapy resulted in improved glycemic control and reduced fasting blood glucose in both groups.Of note,following treatment for six months,a reduction of FLI and APRI,as well as of the FibroScan result,was reported in patients treated with SGLT2-I,but not in the OTHER group;furthermore,in the SGLT2-I group,we reported lower circulating levels of interleukin(IL)-1β,IL-6,tumor necrosis factor,vascular endothelial growth factor,and monocyte chemoattractant protein-1,and higher levels of IL-4 and IL-10.We did not observe any modification in circulating interleukins in the OTHER group.Finally,serum HNE-and MDA-protein adducts decreased significantly in SGLT2-I rathe展开更多
Pt/activated carbon （Pt/AC） catalyst combined with base works efficiently for lactic acid production from glycerol under mild conditions. Base type （LiOH, NaOH, KOH, or Ba（OH）2） and base/glycerol molar ratio sig...Pt/activated carbon （Pt/AC） catalyst combined with base works efficiently for lactic acid production from glycerol under mild conditions. Base type （LiOH, NaOH, KOH, or Ba（OH）2） and base/glycerol molar ratio significantly affected the catalytic performance. The corresponding lactic acid selectivity was in the order of LiOH〉NaOH〉KOH〉Ba（OH）2. An increase in LiOH/glycerol molar ratio ele‐vated the glycerol conversion and lactic acid selectivity to some degree, but excess LiOH inhibited the transformation of glycerol to lactic acid. In the presence of Pt/AC catalyst, the maximum selec‐tivity of lactic acid was 69.3% at a glycerol conversion of 100% after 6 h at 90 °C, with a Li‐OH/glycerol molar ratio of 1.5. The Pt/AC catalyst was recycled five times and was found to exhibit slightly decreased glycerol conversion and stable lactic acid selectivity. In addition, the experimental results indicated that reaction intermediate dihydroxyacetone was more favorable as the starting reagent for lactic acid formation than glyceraldehyde. However, the Pt/AC catalyst had adverse effects on the intermediate transformation to lactic acid, because it favored the catalytic oxidation of them to glyceric acid.展开更多
Chronic hyperglycemia statue noticed in diabetes mellitus favors the manifestation of oxidative stress by increasing the production of reactive oxygen species and/or by reducing the antioxidant defense system activity...Chronic hyperglycemia statue noticed in diabetes mellitus favors the manifestation of oxidative stress by increasing the production of reactive oxygen species and/or by reducing the antioxidant defense system activity.Zinc plays an important role in antioxidant defense in type2 diabetic patients by notably acting as a cofactor of the superoxide dismutase enzyme,by modulating the glutathione metabolism and metallothionein expression,by competing with iron and copper in the cell membrane and by inhibiting nicotinamide adenine dinucleotide phosphate-oxidase enzyme.Zinc also improves the oxidative stress in these patients by reducing chronic hyperglycemia.It indeed promotes phosphorylation of insulin receptors by enhancing transport of glucose into cells.However,several studies reveal changes in zinc metabolism in individuals with type 2 diabetes mellitus and controversies remain regarding the effect of zinc supplementation in the improvement of oxidative stress in these patients.Faced with the serious challenge of the metabolic disorders related to oxidative stress in diabetes along with the importance of antioxidant nutrients in the control of this disease,new studies may contribute to improve our understanding of the role played by zinc against oxidative stress and its connection with type 2 diabetes mellitus prognosis.This could serve as a prelude to the development of prevention strategies and treatment of disorders associated with this chronic disease.展开更多
Background Studies have shown that complications in type 1 diabetes mellitus （T1DM） in children are mainly due to oxidative stress （OS）. Lipid peroxidation is the main marker of OS and iso-prostaglandin is a relia...Background Studies have shown that complications in type 1 diabetes mellitus （T1DM） in children are mainly due to oxidative stress （OS）. Lipid peroxidation is the main marker of OS and iso-prostaglandin is a reliable biomarker of lipid peroxidation in type 2 diabetes mellitus （T2DM）. However, there have been few studies on OS in T1DM children with hyperglycemia and glucose fluctuations.展开更多
Negative permittivity has been widely studied in various metamaterials and percolating composites, of which the anomalous dielectric behavior was attributed to critical structural properties of building blocks.Herein,...Negative permittivity has been widely studied in various metamaterials and percolating composites, of which the anomalous dielectric behavior was attributed to critical structural properties of building blocks.Herein, mono-phase ceramics of indium tin oxides(ITO) were sintered for epsilon-negative materials in MHz-k Hz frequency regions. Electrical conductivity and complex permittivity were analyzed with DrudeLorentz oscillator model. Carriers’ characters were measured based on Hall effect and the magnitude and frequency dispersion of negative permittivity were mainly determined by carrier concentration.Temperature-dependent dielectric properties further proved the epsilon-negative behaviors were closely associated with free carriers’ collective responses. It’s found that negative permittivity of ITO ceramics was mainly caused by plasma oscillations of free carriers, while the dielectric loss was mainly attributed to conduction loss. Negative permittivity realized here was related to materials intrinsic nature and this work preliminarily determined the mechanism of negative permittivity in doped ceramics from the perspective of carriers.展开更多
Uranium exploration breakthrough was extremely rare in an aeolian depositional system.In order to know the complicate characteristics of oxidation associated closely with uranium mineralization in the aeolian depositi...Uranium exploration breakthrough was extremely rare in an aeolian depositional system.In order to know the complicate characteristics of oxidation associated closely with uranium mineralization in the aeolian depositional system,petrology and mineralogy markers of the oxidation and its genetic mechanisms are identified and illustrated by fieldwork,thin section analysis and scanning electron microscopy test,based on 2 field outcrops in Zhenyuan County in the southwest of the Tianhuan depression in the Ordos Basin and the core of 2 wells in the north and south of Ordos Basin.The results showed:the typical macroscopic indicator of primary oxidation was the red fine sediments in the aeolian interdune with a thickness of 10-50 cm,and the microscopic characteristics of primary oxidation were the minerals such as hematite,ilmenite,and the irony matrix rich in fine-grained dolomite and biotite;the phreatic oxidation was manifested as the red sandstone with limonite horizontal layer with a thickness of 1-4 cm and a width of 60 cm-1 m,and the circular limonite nodules with a diameter of 3-7 cm,in which there was intergranular limonite cement;the interlayer oxidation was characterized by lenticular tongue and tapered red sandstone with a length of 1-10 m and a width of 10 cm-5m,in which detrital particles are coated with hematite and hematite was distributed inside the rhombus dolomite.The paleoclimate of the sedimentary period,the water-table movement and the pore and permeability conditions of the sand body were the key factors for the formation of different oxidation types in the aeolian depositional system.展开更多
文摘Background Diabetic macrovascular complications are important causes of cardiovascular and cerebrovascular diseases and also one of the major causes of morbidity and mortality in patients with type 2 diabetes mellitus （T2DM）. Phlorizin has been reported to be effective in reducing the blood glucose level in diabetic mellitus, while little is known about its effects on vascular complications. This study aimed to observe the effects of phlorizin on the aorta of diabetes db/db mice and explore its mechanism. Methods Diabetic db/db mice （n=16） and age-matched db/m mice （n=8） were divided into three groups： normal control group （CC group, db/m mice, n=8）, untreated diabetic group （DM group, db/db mice, n=8） and diabetic group treated by phlorizin （DMT group, db/db mice, n=8）. Phlorizin （20 mg/kg body weight） was given in normal saline solution intragastrically for 10 weeks. Animals were weighed weekly. At the 10th weekend, all mice were fasted overnight and then sacrificed. Fasting blood was collected, and the aortas were dissected. The blood samples were analyzed for fasting blood glucose （FBG）, serum advanced glycation end products （AGEs）, malondialdehyde （MDA） and superoxide dismutase （SOD） activity, the aortic ultrastructure was studied. Results The weight and serum concentration of FBG, AGEs, and MDA in the DM group were higher than that in the CC group （P 〈0.01 ）, and they were significantly lower in the DMT group （P 〈0.05）. Serum SOD activity was lower than that in the CC group （P 〈0.01）, and it is significantly higher in the DMT group （P 〈0.05）. The severity of aorta damage in the DMT group was less than that in the DM group. Conclusions Phlorizin protected the db/db mice from diabetic macrovascular complications, attributed to the decreasing of blood glucose and AGEs level, and its antioxidant potential. This study may provide a new natural medicine for treating diabetic macrovascular complications.
文摘BACKGROUND Sodium glucose cotransporter-2 inhibitors(SGLT2-I)are the most recently approved drugs for type 2 diabetes(T2D).Recent clinical trials of these compounds reported beneficial cardiovascular(CV)and renal outcomes.A major cause of vascular dysfunction and CV disease in diabetes is hyperglycemia associated with inflammation and oxidative stress.Pre-clinical studies demonstrated that SGLT2-I reduce glucotoxicity and promote anti-inflammatory effects by lowering oxidative stress.AIM To investigate the effects of SGLT2-I on markers of oxidative stress,inflammation,liver steatosis,and fibrosis in patients of T2D with non-alcoholic fatty liver disease(NAFLD).METHODS We referred fifty-two consecutive outpatients treated with metformin monotherapy and exhibiting poor glycemic control to our centre.We introduced the outpatients to an SGLT2-I(dapagliflozin,empagliflozin,or canagliflozin;n=26)or a different hypoglycemic drug[other glucose-lowering drugs(OTHER),n=26].We evaluated circulating interleukins and serum hydroxynonenal(HNE)-or malondialdehyde(MDA)-protein adducts,fatty liver index(FLI),NAFLD fibrosis score,aspartate aminotransferase(AST)/alanine aminotransferase(ALT)ratio,AST-to-platelet-ratio index(APRI),and fibrosis-4 on the day before(T0)and following treatment for six months(T1).We also performed transient elastography at T0 and T1.RESULTS Add-on therapy resulted in improved glycemic control and reduced fasting blood glucose in both groups.Of note,following treatment for six months,a reduction of FLI and APRI,as well as of the FibroScan result,was reported in patients treated with SGLT2-I,but not in the OTHER group;furthermore,in the SGLT2-I group,we reported lower circulating levels of interleukin(IL)-1β,IL-6,tumor necrosis factor,vascular endothelial growth factor,and monocyte chemoattractant protein-1,and higher levels of IL-4 and IL-10.We did not observe any modification in circulating interleukins in the OTHER group.Finally,serum HNE-and MDA-protein adducts decreased significantly in SGLT2-I rathe
基金supported by the National Natural Science Foundation of China(21176236)~~
文摘Pt/activated carbon （Pt/AC） catalyst combined with base works efficiently for lactic acid production from glycerol under mild conditions. Base type （LiOH, NaOH, KOH, or Ba（OH）2） and base/glycerol molar ratio significantly affected the catalytic performance. The corresponding lactic acid selectivity was in the order of LiOH〉NaOH〉KOH〉Ba（OH）2. An increase in LiOH/glycerol molar ratio ele‐vated the glycerol conversion and lactic acid selectivity to some degree, but excess LiOH inhibited the transformation of glycerol to lactic acid. In the presence of Pt/AC catalyst, the maximum selec‐tivity of lactic acid was 69.3% at a glycerol conversion of 100% after 6 h at 90 °C, with a Li‐OH/glycerol molar ratio of 1.5. The Pt/AC catalyst was recycled five times and was found to exhibit slightly decreased glycerol conversion and stable lactic acid selectivity. In addition, the experimental results indicated that reaction intermediate dihydroxyacetone was more favorable as the starting reagent for lactic acid formation than glyceraldehyde. However, the Pt/AC catalyst had adverse effects on the intermediate transformation to lactic acid, because it favored the catalytic oxidation of them to glyceric acid.
文摘Chronic hyperglycemia statue noticed in diabetes mellitus favors the manifestation of oxidative stress by increasing the production of reactive oxygen species and/or by reducing the antioxidant defense system activity.Zinc plays an important role in antioxidant defense in type2 diabetic patients by notably acting as a cofactor of the superoxide dismutase enzyme,by modulating the glutathione metabolism and metallothionein expression,by competing with iron and copper in the cell membrane and by inhibiting nicotinamide adenine dinucleotide phosphate-oxidase enzyme.Zinc also improves the oxidative stress in these patients by reducing chronic hyperglycemia.It indeed promotes phosphorylation of insulin receptors by enhancing transport of glucose into cells.However,several studies reveal changes in zinc metabolism in individuals with type 2 diabetes mellitus and controversies remain regarding the effect of zinc supplementation in the improvement of oxidative stress in these patients.Faced with the serious challenge of the metabolic disorders related to oxidative stress in diabetes along with the importance of antioxidant nutrients in the control of this disease,new studies may contribute to improve our understanding of the role played by zinc against oxidative stress and its connection with type 2 diabetes mellitus prognosis.This could serve as a prelude to the development of prevention strategies and treatment of disorders associated with this chronic disease.
文摘Background Studies have shown that complications in type 1 diabetes mellitus （T1DM） in children are mainly due to oxidative stress （OS）. Lipid peroxidation is the main marker of OS and iso-prostaglandin is a reliable biomarker of lipid peroxidation in type 2 diabetes mellitus （T2DM）. However, there have been few studies on OS in T1DM children with hyperglycemia and glucose fluctuations.
基金supported by the National Natural Science Foundation of China(Nos.51771104,51871146,51971119)the Future Plan for Young Talent of Shandong University(No.2016WLJH40)the Innovation Program of Shanghai Municipal Education Commission(No.2019-01-07-00-10-E00053)。
文摘Negative permittivity has been widely studied in various metamaterials and percolating composites, of which the anomalous dielectric behavior was attributed to critical structural properties of building blocks.Herein, mono-phase ceramics of indium tin oxides(ITO) were sintered for epsilon-negative materials in MHz-k Hz frequency regions. Electrical conductivity and complex permittivity were analyzed with DrudeLorentz oscillator model. Carriers’ characters were measured based on Hall effect and the magnitude and frequency dispersion of negative permittivity were mainly determined by carrier concentration.Temperature-dependent dielectric properties further proved the epsilon-negative behaviors were closely associated with free carriers’ collective responses. It’s found that negative permittivity of ITO ceramics was mainly caused by plasma oscillations of free carriers, while the dielectric loss was mainly attributed to conduction loss. Negative permittivity realized here was related to materials intrinsic nature and this work preliminarily determined the mechanism of negative permittivity in doped ceramics from the perspective of carriers.
基金supported by the National Key Research and Development Program of China (No.2018YFC0604202)from the Ministry of Science and Technology of China and the International Geosciences Program (No.IGCP675)
文摘Uranium exploration breakthrough was extremely rare in an aeolian depositional system.In order to know the complicate characteristics of oxidation associated closely with uranium mineralization in the aeolian depositional system,petrology and mineralogy markers of the oxidation and its genetic mechanisms are identified and illustrated by fieldwork,thin section analysis and scanning electron microscopy test,based on 2 field outcrops in Zhenyuan County in the southwest of the Tianhuan depression in the Ordos Basin and the core of 2 wells in the north and south of Ordos Basin.The results showed:the typical macroscopic indicator of primary oxidation was the red fine sediments in the aeolian interdune with a thickness of 10-50 cm,and the microscopic characteristics of primary oxidation were the minerals such as hematite,ilmenite,and the irony matrix rich in fine-grained dolomite and biotite;the phreatic oxidation was manifested as the red sandstone with limonite horizontal layer with a thickness of 1-4 cm and a width of 60 cm-1 m,and the circular limonite nodules with a diameter of 3-7 cm,in which there was intergranular limonite cement;the interlayer oxidation was characterized by lenticular tongue and tapered red sandstone with a length of 1-10 m and a width of 10 cm-5m,in which detrital particles are coated with hematite and hematite was distributed inside the rhombus dolomite.The paleoclimate of the sedimentary period,the water-table movement and the pore and permeability conditions of the sand body were the key factors for the formation of different oxidation types in the aeolian depositional system.
