With the sublattice model, equilibrium compositions of ferrite (a) and austenite (7 ) phases, as well as the volume percent of austenite (7) at 780℃ in different TRIP steels were calculated. Concentration profiles of...With the sublattice model, equilibrium compositions of ferrite (a) and austenite (7 ) phases, as well as the volume percent of austenite (7) at 780℃ in different TRIP steels were calculated. Concentration profiles of carbon, Mn, Al and Si in the steels were also estimated under the lattice fixed frame of reference so as to understand the complex mechanical behavior of TRIP steels after different isothermal bainitic transformation treatments. The effect of Si and Mn on transformation induced plasticity (TRIP) was discussed according to thermodynamic and kinetic analyses. It is recognized that Al also induces phase transformation in the steels but its TRIP effect is not as strong as that of Si.展开更多
Wnt signaling plays an important role in embryogenesis and tumorgenesis. Although the mechanism about how Wnts transduce their signaling from receptor frizzled (Fz) to cytosol has not been understood, dishevelled (Dvl...Wnt signaling plays an important role in embryogenesis and tumorgenesis. Although the mechanism about how Wnts transduce their signaling from receptor frizzled (Fz) to cytosol has not been understood, dishevelled (Dvl) protein was considered as the intersection of Wnt signal traffic. In this study, we characterized the function of three domains (DIX,PDZ and DEP) of Dvl-1 in canonical Wnt signal transduction and Dvl-1 membrane translocation. It was found both DIX and DEP domain were sufficient to block Wnt-3a-induced LEF-1 transcriptional activity and free cytosol β-catenin accumulation; whereas PDZ domain and a functional mutant form of DEP domain (DEP-KM) had no effect on canonical Wnt signaling. In addition, when cotransfected with Fz-7, DEP domain, but not DIX, PDZ or DEP-KM, translocated and co-localized with Fz-7 to the plasma membrane, which was similar to Dvl-1. Furthermore, it was DEP domain that could block Fz-7-induced membrane translocation of Dvl- 1 via a possible competitive mechanism. These results strongly suggest that DEP domain is responsible for the membrane translocation of Dvl-1 protein upon Wnt signal stimulation.展开更多
With the two sublattices model, equilibrium compositions of ferrite (α) and austenite (γ) phases, as well as the volume percent of austenite (γ) in different TRIP steels are calculated. Concentration profiles of ca...With the two sublattices model, equilibrium compositions of ferrite (α) and austenite (γ) phases, as well as the volume percent of austenite (γ) in different TRIP steels are calculated. Concentration profiles of carbon, manganese, aluminum and silicon in these steels are also estimated under the lattice fixed frame of reference so as to identify if the equilibrium state is obtained. Through the comparison between the profiles after different time diffusion, the distribution of elements in phases is exhibited and the complex effect due to the mutual interaction of the elements on diffusion is discussed.展开更多
The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional preha...The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional prehardened mould steel for plastic markedly influences the precipitation of non-metallic inclusion and the control of composition aided by Thermo-Calc software package minimizes the amount of detrimental oxide inclusion. In addition the modification of calcium is optimized in the light of composition design.展开更多
Thermal groundwater resources were found to have occurred in deep-seated bedrock aquifers in the northeastern North China plain near Tianjin, China. Meso- to Neo-Proterozoic and Paleozoic carbonate rocks on the Cangxi...Thermal groundwater resources were found to have occurred in deep-seated bedrock aquifers in the northeastern North China plain near Tianjin, China. Meso- to Neo-Proterozoic and Paleozoic carbonate rocks on the Cangxian uplift are capable of yielding 960-4 200 m 3/d of 60 to 96 ℃ water from the wells ranging in depth between 1 000 and 4 000 m. Conductive heat flow of 0.063 to 0.144 2 W/m 2 from the deep crust is responsible for this anomalous geothermal field. The water in the Ordovician aquifer is characterized by relatively high TDS, high concentrations of SO 4 and SO 4·Cl-Na·Ca type, but the waters from the Meso- to Neo-Proterozoic and Cambrian aquifers, by relatively low TDS, low concentrations of SO 4 and predominantly Cl·SO 4-Na type. It is noted that when the temperature of the waters increases at a rate of 10 ℃ in the range of 30-100 ℃, the content of SiO 2 increases at a rate of 12 to 15 mg/L, and fluoride concentration increases at a rate of 2.3 to 2.5 mg/L. Hydrochemical and isotopic data suggest that the thermal water in the bedrock aquifers is of meteoric origin and recharged in the northern mountain area to the north of the Baodi-Ninghe fault, and then flows laterally for a long distance from the north to the south to the city of Tianjin. Temperature of the waters increases because of heat exchange with the rocks and recharge by conductive heat flow from beneath.展开更多
Using compound energy model (CEM), the thermodynamic properties of <CeO2-y> and <Zr1_xCezO2-x> were evaluated. The evaluation was based on the optimization of ZrIO2-CeO2 and ZrO2-CeO1.5 systems, as well as...Using compound energy model (CEM), the thermodynamic properties of <CeO2-y> and <Zr1_xCezO2-x> were evaluated. The evaluation was based on the optimization of ZrIO2-CeO2 and ZrO2-CeO1.5 systems, as well as the miscibility gap in CeO1.5-CeO2 system. Except the cubic fluorite structure phase assessed with compound energy model, all the other solution phases were assessed with subsitutional solution model. The model parameters were evaluated through fitting the selected experimental data by means of thermodynamic optimization. A set of parameters with thermodynamics self-consistency was obtained and satisfactorily described the complex relation between y in <CeO2-y> and the partial pressure of oxygen at different temperatures, also the interdependence among miscellaneous factors such as temperature, oxygen partial pressure, the reduction amount of CeO2 as well as the nonstoichiometry in cubic phase <Zr1-xCezO2-x>- The calculated results seem to be reasonable when put into the explanation of pressureless sintering of Ce02-stabilized ZrO2 powder compacts at a controlled oxygen partial pressure.展开更多
AIM: To study the pathway of apoptosis in chronic liver disease and the role of mitochondria in programmed cell death.METHODS: Liver biopsy specimens from 72 cases of chronic hepatitis and 29 cases of post hepatitis c...AIM: To study the pathway of apoptosis in chronic liver disease and the role of mitochondria in programmed cell death.METHODS: Liver biopsy specimens from 72 cases of chronic hepatitis and 29 cases of post hepatitis cirrhosis were studied. The pro-apoptotic protein Fas, FasL, Bax and the anti-apoptotic protein Bcl-2, Bcl-xL, Bcl-2α were studied immunohistochemically by SP method. Specimens from 15 cases of chronic hepatitis and post hepatitis cirrhosis were examined for their ultramicrostructures with special attention to their mitochondrial changes. Specimens from 3 normal adults (demised in traffic accidents) were used as control.RESULTS: The expression of proapoptotic proteins (Fas, FasL, Bax) in hepatocytes was significantly higher in the chronic hepatitis group than in the cirrhosis group (P<0.001). In the study of ultramicrostructure 364 hepatocytes were examined, from 12 cases of chronic hepatitis (including 10 mild cases, 1 moderate case and 1 severe case). Out of 364 hepatocytes 40 (11.0%) hepatocytes were found with various kinds of destruction in their mitochondria. Rupture of the outer membrane of mitochondria and the leakage of matrix from the intermembrane space were definitely demonstrated. The ultramicrostructural changes of mitochondria in the chronic hepatitis group were statistically higher than that in normal adults control group(X^2=4.32, P<0.05). CONCLUSION: The result of the study was in support of the current view that the apoptotic process in chronic hepatitis patients were largely along the intrinsic pathway (mitochondrial pathway), given that the intrinsic and extrinsic pathways could interlinked (converged) at some point on their progression, also it is impossible at present to exclude the possibility that the two pathways could be chosen by hepatocytes in parallel simultaneously.展开更多
A new chemically modified electrode(CME) immobilized on the surface of multi-wall carbon nanotubes functionalized with carboxylic groups was fabricated. The results indicate that the CME exhibits efficiently electroca...A new chemically modified electrode(CME) immobilized on the surface of multi-wall carbon nanotubes functionalized with carboxylic groups was fabricated. The results indicate that the CME exhibits efficiently electrocatalytic oxidation of 6-mercaptopurine(6-MP). The CME can be used as the working electrode in the liquid chromatography for the determination of 6-MP. The peak current of 6-MP is linearly changed with its concentration ranging from 4.0×10 -7 to 1.0×10 -4 mol/L with the calculated detection limit (S/N=3) of 2.0×10 -7 mol/L. Coupled with microdialysis sampling, the method has been successfully applied to assessing the content of 6-MP in rat blood.展开更多
The ZrO2-CeO2-AI2O3 system has been assessed with the CALPHAD (Calculation of Phase Diagrams) technique using the PARROT procedure. The experimental information on the ZrO2-AI2O3, AI2O3-CeO2 systems as well as the iso...The ZrO2-CeO2-AI2O3 system has been assessed with the CALPHAD (Calculation of Phase Diagrams) technique using the PARROT procedure. The experimental information on the ZrO2-AI2O3, AI2O3-CeO2 systems as well as the isothermal sections of the ternary system at 1673 K and 1873 K is well reproduced. According to the assessed isothermal section at 1723 K, no alumina dissolves into the tetragonal zirconia phase. Specimens with different alumina content are fabricated from commercial 12 mol pct CeO2-stabilized ZrO2 powder (12Ce-ZrO2). The thermodynamic properties are consistent with the observed microstructure, which present a combination of tetragonal phase and alumina grains.展开更多
Spike protein is one of the major structural proteins of severe acute respiratory syndrome-coronavirus. It is essential for the interaction of the virons with host cell receptors and subsequent fusion of the viral env...Spike protein is one of the major structural proteins of severe acute respiratory syndrome-coronavirus. It is essential for the interaction of the virons with host cell receptors and subsequent fusion of the viral envelop with host cell membrane to allow infection. Some spike proteins of coronavirus, such as MHV, HCoV-OC43, AIBV and BcoV, are proteolytically cleaved into two subunits, S 1 and S2. In contrast, TGV, FIPV and HCoV-229E are not. Many studies have shown that the cleavage of spike protein seriously affects its function. In order to investigate the maturation and proteolytic processing of the S protein of SARS CoV, we generated S 1 and S2 subunit specific antibodies (Abs) as well as N, E and 3CL protein-specific Abs. Our results showed that the antibodies could efficiently and specifically bind to their corresponding proteins from E.coli expressed or lysate of SARS-CoV infected Vero-E6 cells by Western blot analysis. Furthermore, the anti-S 1 and S2 Abs were proved to be capable of binding to SARS CoV under electron microscope observation. When S2 Ab was used to perform immune precipitation with lysate of SARS-CoV infected cells, a cleaved S2 fragment was detected with S2-specific mAb by Western blot analysis. The data demonstrated that the cleavage of S protein was observed in the lysate, indicating that proteolytic processing of S protein is present in host cells.展开更多
OBJECTIVE The aim of the present study was to investigate the effect of cornel iridoid glycoside(CIG)on tau hyperphosphorylation induced by wortmannin(WT)and GF-109203X(GFX)and the underlying mechanisms.METHODS Human ...OBJECTIVE The aim of the present study was to investigate the effect of cornel iridoid glycoside(CIG)on tau hyperphosphorylation induced by wortmannin(WT)and GF-109203X(GFX)and the underlying mechanisms.METHODS Human neuroblastoma SK-N-SH cells were pre-incubated with CIG(50,100,and 200μg·mL-1,respectively)for 24 h,and then exposed to WT 10μmol·L-1 and GFX 10μmol·L-1for 3hafter washing out CIG.Immuno-fluorescence was used to observe the microtubular cytoskeleton of the cultured cells.Western blotting was used to measure the phosphorylation level of tau protein,glycogen synthase kinase 3β(GSK-3β)and protein phosphatase 2A(PP2A).The activity of PP2 Awas detected by a biochemical assay.RESULTS Pre-incubation of CIG significantly attenuated the WT/GFX-induced tau hyperphosphorylation at the sites of Thr205,Thr212,Ser214,Thr217Ser396 and PHF-1,and improved the damage of morphology and microtubular cytoskeleton of the cells.CIG did not prevent the decrease in p-AKT-ser473 and pGSK3β-ser9 induced by WT/GFX.However,CIG significantly elevated the activity of PP2 Aby reducing the demethylation of PP2AC at Leu309 and the ratio of PME-1/LCMT in the WT/GFX-treated cells.CONCLUSION CIG obviously attenuated WT/GFX-induced tau hyper-phosphorylation at multiple AD-related sites by increasing the activity of PP2A.The mechanism may be involved in the reduced demethylation of PP2 Avia down regulating the ratio of PME/LCMT.展开更多
OBJECTIVE In order to investigate whether cornel iridoid glycoside(CIG),the main component extracted from Cornus officinalis,can treat demyelinating diseases of the central nervous system(CNS)such as multiple sclerosi...OBJECTIVE In order to investigate whether cornel iridoid glycoside(CIG),the main component extracted from Cornus officinalis,can treat demyelinating diseases of the central nervous system(CNS)such as multiple sclerosis(MS).METHODS CIG(30,60 and 120mg·kg-1)or vehicle was intragastrically administered once daily to rats,starting immediately after purified myelin basic protein(MBP)68-86 peptides immunization until day 20 post immunization(p.i.).Histopathological staining,enzyme-linked immunosorbent assay,biochemical methods and Western blotting approaches were used to evaluate the disease incidence and severity,neuroinflammatory and neurotrophic response in the CNS.RESULTS Neurological deficit and proportion of incidence seen in EAE rats were significantly reduced by CIG treatment in a dose-dependent manner.Histopathological staining showed that CIG treatment alleviated demyelination and inflammatory infiltration,increased the number of oligodendrocytes,enhanced the expression of brain-derived neurotrophic factor(BDNF).Production of proinflammatory molecules such as interleukin-1β(IL-1β),tumour necrosis factor-αand interferon-γwere also inhibited by CIG administration.CIG could ameliorate phosphorylation of STAT1,STAT3 and JAK1 as well as IL-6/IL-6 Rexpression,which involved in immune response and inflammation.CONCLUSION Our results demonstrated that CIG may ameliorate EAE rats through down-regulation of JAK/STAT signaling pathway.This study gave new insight into the novel regulatory mechanism of CIG and highlight novel therapeutic targets and a potential therapeutic agent for the treatment of MS.展开更多
The phase constitution of a composite consisting of 12 at. pct CeO_2-3 at. pct Y_2O_3-ZrO_2/2.5 wt pct Al_2O_3 (3Y12Ce2.5Al)was determined by thermodynamic calculation. It is a combination of 36.9 at. pct cubic phase ...The phase constitution of a composite consisting of 12 at. pct CeO_2-3 at. pct Y_2O_3-ZrO_2/2.5 wt pct Al_2O_3 (3Y12Ce2.5Al)was determined by thermodynamic calculation. It is a combination of 36.9 at. pct cubic phase and 63.1 at. pct tetragonalphase at 1450℃. Green compacts were fabricated by cold isostatic pressing with powder synthesized by coating technique,and pressureless sintered at 1450℃. The fracture toughness and Vickers hardness, evaluated by the micro-indentation method,are 2.02 MPa·m^(1/2) and 11.395 GPa, respectively. The addition of 3 at. pct Y_2O_3 to 12 at. pct CeO_2-ZrO_2 ceramic leads todrastically decrease in toughness compared to composites without yttria stabilizer. No monoclinic phase is detected on thesudece of all the ground samples. The high content of cubic phase and lack of phase transformation can be attributed to thelow toughness based on the thermodynamic prediction.展开更多
The application of substitutional model in oxide systems, in comparison with that of sublattice model, is discussed.The results show that in the case of crystalline phases and liquid phases without molecular-like asso...The application of substitutional model in oxide systems, in comparison with that of sublattice model, is discussed.The results show that in the case of crystalline phases and liquid phases without molecular-like associates or theshortage of element in sublattice, these two models get consistent in the description of the formalism of Gibbs freeenergies of phases and obtain the same result of phase diagram calculation when the valence of the cations keep thesame.展开更多
In order to study the effect of fused spinel on the properties of phosphoricacid bonded high alumina castables, samples with different contents of fused spinel were prepared.The results show that when the contents of ...In order to study the effect of fused spinel on the properties of phosphoricacid bonded high alumina castables, samples with different contents of fused spinel were prepared.The results show that when the contents of the fused spinel are between 8% and 16% (mass fraction),the castables have good properties. The castables overcome the shortages of the phosphoric acidbonded high alumina castables with bauxite cement as a hardening promoter. The experimentsdemonstrate that most of the service properties of the castables with fused spinel are better thanthose of the normal phosphoric acid bonded castables which use bauxite cement as a hardeningpromoter. The examination of the materials indicates that free MgO inclusions in the spinel powdercan promote the hardening of the castables.展开更多
AIM To investigate the expression change of α-synuclein in the brain of different age AD-like an-imal model and to explore the pathology mechanism of α-synuclein in neural degeneration and protective effect of 2 kin...AIM To investigate the expression change of α-synuclein in the brain of different age AD-like an-imal model and to explore the pathology mechanism of α-synuclein in neural degeneration and protective effect of 2 kinds of Chinese components. METHODS A generally accepted animal model of Alzheimer' s disease-APP V717I transgenic (Tg) mouse was observed from 4 to 16 month old. The Tg mice wererandomly divided into model group(4 month, 10 month and 16 month old), Shen-wu capsule with the dose of 0.4g and 1.2g/kg/d, 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucoside(TSG), one of effective components in Polygonum muhiflorum, at dose of 0. 05,0.1 and 0.2g/kg/d.展开更多
Objective: to explore the improvement of seamless nursing quality and complication rate of elderly patients with coronary heart disease. Methods: from January 2020 to August 2021,100 cases of elderly coronary heart di...Objective: to explore the improvement of seamless nursing quality and complication rate of elderly patients with coronary heart disease. Methods: from January 2020 to August 2021,100 cases of elderly coronary heart disease admitted to the department of cardiovascular medicine were selected for clinical study and grouped by lottery method. 50 patients with routine care were in the control group, and 50 patients with seamless care were in the observation group. The quality of care with complications in both groups was obtained and compared. Results: the nursing quality score (service attitude, nurse-patient relationship, psychological counseling, knowledge education, nursing safety, and self-feeling) of the observation group was significantly higher than that of the control group (P 0.05). The complication rate in the observation group of 4.00% was significantly less than 18.00% in the control group (P 0.05). Conclusion: seamless nursing during treatment can improve the quality of clinical care, reduce the incidence of complications and have significant promotion value.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(No.50171038)the China-Belgium bilateral project(2001-242).
文摘With the sublattice model, equilibrium compositions of ferrite (a) and austenite (7 ) phases, as well as the volume percent of austenite (7) at 780℃ in different TRIP steels were calculated. Concentration profiles of carbon, Mn, Al and Si in the steels were also estimated under the lattice fixed frame of reference so as to understand the complex mechanical behavior of TRIP steels after different isothermal bainitic transformation treatments. The effect of Si and Mn on transformation induced plasticity (TRIP) was discussed according to thermodynamic and kinetic analyses. It is recognized that Al also induces phase transformation in the steels but its TRIP effect is not as strong as that of Si.
文摘Wnt signaling plays an important role in embryogenesis and tumorgenesis. Although the mechanism about how Wnts transduce their signaling from receptor frizzled (Fz) to cytosol has not been understood, dishevelled (Dvl) protein was considered as the intersection of Wnt signal traffic. In this study, we characterized the function of three domains (DIX,PDZ and DEP) of Dvl-1 in canonical Wnt signal transduction and Dvl-1 membrane translocation. It was found both DIX and DEP domain were sufficient to block Wnt-3a-induced LEF-1 transcriptional activity and free cytosol β-catenin accumulation; whereas PDZ domain and a functional mutant form of DEP domain (DEP-KM) had no effect on canonical Wnt signaling. In addition, when cotransfected with Fz-7, DEP domain, but not DIX, PDZ or DEP-KM, translocated and co-localized with Fz-7 to the plasma membrane, which was similar to Dvl-1. Furthermore, it was DEP domain that could block Fz-7-induced membrane translocation of Dvl- 1 via a possible competitive mechanism. These results strongly suggest that DEP domain is responsible for the membrane translocation of Dvl-1 protein upon Wnt signal stimulation.
文摘With the two sublattices model, equilibrium compositions of ferrite (α) and austenite (γ) phases, as well as the volume percent of austenite (γ) in different TRIP steels are calculated. Concentration profiles of carbon, manganese, aluminum and silicon in these steels are also estimated under the lattice fixed frame of reference so as to identify if the equilibrium state is obtained. Through the comparison between the profiles after different time diffusion, the distribution of elements in phases is exhibited and the complex effect due to the mutual interaction of the elements on diffusion is discussed.
文摘The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional prehardened mould steel for plastic markedly influences the precipitation of non-metallic inclusion and the control of composition aided by Thermo-Calc software package minimizes the amount of detrimental oxide inclusion. In addition the modification of calcium is optimized in the light of composition design.
基金ThisworkisfundedbytheMinistryofEducationofChinafortheKeyProjectsofScienceandTechnologyResearch (No .0 2 0 2 6)
文摘Thermal groundwater resources were found to have occurred in deep-seated bedrock aquifers in the northeastern North China plain near Tianjin, China. Meso- to Neo-Proterozoic and Paleozoic carbonate rocks on the Cangxian uplift are capable of yielding 960-4 200 m 3/d of 60 to 96 ℃ water from the wells ranging in depth between 1 000 and 4 000 m. Conductive heat flow of 0.063 to 0.144 2 W/m 2 from the deep crust is responsible for this anomalous geothermal field. The water in the Ordovician aquifer is characterized by relatively high TDS, high concentrations of SO 4 and SO 4·Cl-Na·Ca type, but the waters from the Meso- to Neo-Proterozoic and Cambrian aquifers, by relatively low TDS, low concentrations of SO 4 and predominantly Cl·SO 4-Na type. It is noted that when the temperature of the waters increases at a rate of 10 ℃ in the range of 30-100 ℃, the content of SiO 2 increases at a rate of 12 to 15 mg/L, and fluoride concentration increases at a rate of 2.3 to 2.5 mg/L. Hydrochemical and isotopic data suggest that the thermal water in the bedrock aquifers is of meteoric origin and recharged in the northern mountain area to the north of the Baodi-Ninghe fault, and then flows laterally for a long distance from the north to the south to the city of Tianjin. Temperature of the waters increases because of heat exchange with the rocks and recharge by conductive heat flow from beneath.
基金This paper is financially supported by the Flanders-China bilateral project (BIL 99/10)the Science and Technology Committee of Shanghai Municipality +1 种基金the State Key Lab of High Performance Ceramics Superfine Microstructure of Chinese Academy of Scien
文摘Using compound energy model (CEM), the thermodynamic properties of <CeO2-y> and <Zr1_xCezO2-x> were evaluated. The evaluation was based on the optimization of ZrIO2-CeO2 and ZrO2-CeO1.5 systems, as well as the miscibility gap in CeO1.5-CeO2 system. Except the cubic fluorite structure phase assessed with compound energy model, all the other solution phases were assessed with subsitutional solution model. The model parameters were evaluated through fitting the selected experimental data by means of thermodynamic optimization. A set of parameters with thermodynamics self-consistency was obtained and satisfactorily described the complex relation between y in <CeO2-y> and the partial pressure of oxygen at different temperatures, also the interdependence among miscellaneous factors such as temperature, oxygen partial pressure, the reduction amount of CeO2 as well as the nonstoichiometry in cubic phase <Zr1-xCezO2-x>- The calculated results seem to be reasonable when put into the explanation of pressureless sintering of Ce02-stabilized ZrO2 powder compacts at a controlled oxygen partial pressure.
基金Supported by the National Natural Science Foundation of China,No.39770660 and the Beijing Military Command Foundation,No.95B008 and the Social Development Program of Lianyungang City,No.SH 0210
文摘AIM: To study the pathway of apoptosis in chronic liver disease and the role of mitochondria in programmed cell death.METHODS: Liver biopsy specimens from 72 cases of chronic hepatitis and 29 cases of post hepatitis cirrhosis were studied. The pro-apoptotic protein Fas, FasL, Bax and the anti-apoptotic protein Bcl-2, Bcl-xL, Bcl-2α were studied immunohistochemically by SP method. Specimens from 15 cases of chronic hepatitis and post hepatitis cirrhosis were examined for their ultramicrostructures with special attention to their mitochondrial changes. Specimens from 3 normal adults (demised in traffic accidents) were used as control.RESULTS: The expression of proapoptotic proteins (Fas, FasL, Bax) in hepatocytes was significantly higher in the chronic hepatitis group than in the cirrhosis group (P<0.001). In the study of ultramicrostructure 364 hepatocytes were examined, from 12 cases of chronic hepatitis (including 10 mild cases, 1 moderate case and 1 severe case). Out of 364 hepatocytes 40 (11.0%) hepatocytes were found with various kinds of destruction in their mitochondria. Rupture of the outer membrane of mitochondria and the leakage of matrix from the intermembrane space were definitely demonstrated. The ultramicrostructural changes of mitochondria in the chronic hepatitis group were statistically higher than that in normal adults control group(X^2=4.32, P<0.05). CONCLUSION: The result of the study was in support of the current view that the apoptotic process in chronic hepatitis patients were largely along the intrinsic pathway (mitochondrial pathway), given that the intrinsic and extrinsic pathways could interlinked (converged) at some point on their progression, also it is impossible at present to exclude the possibility that the two pathways could be chosen by hepatocytes in parallel simultaneously.
文摘A new chemically modified electrode(CME) immobilized on the surface of multi-wall carbon nanotubes functionalized with carboxylic groups was fabricated. The results indicate that the CME exhibits efficiently electrocatalytic oxidation of 6-mercaptopurine(6-MP). The CME can be used as the working electrode in the liquid chromatography for the determination of 6-MP. The peak current of 6-MP is linearly changed with its concentration ranging from 4.0×10 -7 to 1.0×10 -4 mol/L with the calculated detection limit (S/N=3) of 2.0×10 -7 mol/L. Coupled with microdialysis sampling, the method has been successfully applied to assessing the content of 6-MP in rat blood.
基金supported by the Flanders-China bilateral project(BIL 99/10)the Science and Technology Committee of Shanghai Municipalitythe Commission of the European Communities in the framework of the Growth Project"BIOGRAD"(G5RD-CT2000-00354)
文摘The ZrO2-CeO2-AI2O3 system has been assessed with the CALPHAD (Calculation of Phase Diagrams) technique using the PARROT procedure. The experimental information on the ZrO2-AI2O3, AI2O3-CeO2 systems as well as the isothermal sections of the ternary system at 1673 K and 1873 K is well reproduced. According to the assessed isothermal section at 1723 K, no alumina dissolves into the tetragonal zirconia phase. Specimens with different alumina content are fabricated from commercial 12 mol pct CeO2-stabilized ZrO2 powder (12Ce-ZrO2). The thermodynamic properties are consistent with the observed microstructure, which present a combination of tetragonal phase and alumina grains.
基金This work is financially supported by the FlandersChina bilateral project (BIL 99/10) and the Science and Technology Committee of Shanghai Municipality. The authors are thankful to Prof. H.L.Lukas, offering the new version of the Lukas Program.
文摘Spike protein is one of the major structural proteins of severe acute respiratory syndrome-coronavirus. It is essential for the interaction of the virons with host cell receptors and subsequent fusion of the viral envelop with host cell membrane to allow infection. Some spike proteins of coronavirus, such as MHV, HCoV-OC43, AIBV and BcoV, are proteolytically cleaved into two subunits, S 1 and S2. In contrast, TGV, FIPV and HCoV-229E are not. Many studies have shown that the cleavage of spike protein seriously affects its function. In order to investigate the maturation and proteolytic processing of the S protein of SARS CoV, we generated S 1 and S2 subunit specific antibodies (Abs) as well as N, E and 3CL protein-specific Abs. Our results showed that the antibodies could efficiently and specifically bind to their corresponding proteins from E.coli expressed or lysate of SARS-CoV infected Vero-E6 cells by Western blot analysis. Furthermore, the anti-S 1 and S2 Abs were proved to be capable of binding to SARS CoV under electron microscope observation. When S2 Ab was used to perform immune precipitation with lysate of SARS-CoV infected cells, a cleaved S2 fragment was detected with S2-specific mAb by Western blot analysis. The data demonstrated that the cleavage of S protein was observed in the lysate, indicating that proteolytic processing of S protein is present in host cells.
基金The project supported by National Natural Science Foundation of China(81274120,81273498)the Beijing Natural Science Foundation(7132110)+1 种基金the Beijing Science and Technology Program(Z131102002813066)the Capital Health Development Scientific Grant(2011-1001-05)
文摘OBJECTIVE The aim of the present study was to investigate the effect of cornel iridoid glycoside(CIG)on tau hyperphosphorylation induced by wortmannin(WT)and GF-109203X(GFX)and the underlying mechanisms.METHODS Human neuroblastoma SK-N-SH cells were pre-incubated with CIG(50,100,and 200μg·mL-1,respectively)for 24 h,and then exposed to WT 10μmol·L-1 and GFX 10μmol·L-1for 3hafter washing out CIG.Immuno-fluorescence was used to observe the microtubular cytoskeleton of the cultured cells.Western blotting was used to measure the phosphorylation level of tau protein,glycogen synthase kinase 3β(GSK-3β)and protein phosphatase 2A(PP2A).The activity of PP2 Awas detected by a biochemical assay.RESULTS Pre-incubation of CIG significantly attenuated the WT/GFX-induced tau hyperphosphorylation at the sites of Thr205,Thr212,Ser214,Thr217Ser396 and PHF-1,and improved the damage of morphology and microtubular cytoskeleton of the cells.CIG did not prevent the decrease in p-AKT-ser473 and pGSK3β-ser9 induced by WT/GFX.However,CIG significantly elevated the activity of PP2 Aby reducing the demethylation of PP2AC at Leu309 and the ratio of PME-1/LCMT in the WT/GFX-treated cells.CONCLUSION CIG obviously attenuated WT/GFX-induced tau hyper-phosphorylation at multiple AD-related sites by increasing the activity of PP2A.The mechanism may be involved in the reduced demethylation of PP2 Avia down regulating the ratio of PME/LCMT.
基金The project supported by National Natural Science Foundation of China(81341088,81001656)Beijing Nova Star Program in Science and Technology(Z12111000250000)
文摘OBJECTIVE In order to investigate whether cornel iridoid glycoside(CIG),the main component extracted from Cornus officinalis,can treat demyelinating diseases of the central nervous system(CNS)such as multiple sclerosis(MS).METHODS CIG(30,60 and 120mg·kg-1)or vehicle was intragastrically administered once daily to rats,starting immediately after purified myelin basic protein(MBP)68-86 peptides immunization until day 20 post immunization(p.i.).Histopathological staining,enzyme-linked immunosorbent assay,biochemical methods and Western blotting approaches were used to evaluate the disease incidence and severity,neuroinflammatory and neurotrophic response in the CNS.RESULTS Neurological deficit and proportion of incidence seen in EAE rats were significantly reduced by CIG treatment in a dose-dependent manner.Histopathological staining showed that CIG treatment alleviated demyelination and inflammatory infiltration,increased the number of oligodendrocytes,enhanced the expression of brain-derived neurotrophic factor(BDNF).Production of proinflammatory molecules such as interleukin-1β(IL-1β),tumour necrosis factor-αand interferon-γwere also inhibited by CIG administration.CIG could ameliorate phosphorylation of STAT1,STAT3 and JAK1 as well as IL-6/IL-6 Rexpression,which involved in immune response and inflammation.CONCLUSION Our results demonstrated that CIG may ameliorate EAE rats through down-regulation of JAK/STAT signaling pathway.This study gave new insight into the novel regulatory mechanism of CIG and highlight novel therapeutic targets and a potential therapeutic agent for the treatment of MS.
基金This work is financiallv supported by the Flanders-China bilateral project(BIL 99/10 and 02/16)the Science and Technology Committee of Shanghai Municipalityand the Commission of the.European Communities in the framework of the Growth Project“BIOGRAD”(G5RD-CT2000-00354).
文摘The phase constitution of a composite consisting of 12 at. pct CeO_2-3 at. pct Y_2O_3-ZrO_2/2.5 wt pct Al_2O_3 (3Y12Ce2.5Al)was determined by thermodynamic calculation. It is a combination of 36.9 at. pct cubic phase and 63.1 at. pct tetragonalphase at 1450℃. Green compacts were fabricated by cold isostatic pressing with powder synthesized by coating technique,and pressureless sintered at 1450℃. The fracture toughness and Vickers hardness, evaluated by the micro-indentation method,are 2.02 MPa·m^(1/2) and 11.395 GPa, respectively. The addition of 3 at. pct Y_2O_3 to 12 at. pct CeO_2-ZrO_2 ceramic leads todrastically decrease in toughness compared to composites without yttria stabilizer. No monoclinic phase is detected on thesudece of all the ground samples. The high content of cubic phase and lack of phase transformation can be attributed to thelow toughness based on the thermodynamic prediction.
文摘The application of substitutional model in oxide systems, in comparison with that of sublattice model, is discussed.The results show that in the case of crystalline phases and liquid phases without molecular-like associates or theshortage of element in sublattice, these two models get consistent in the description of the formalism of Gibbs freeenergies of phases and obtain the same result of phase diagram calculation when the valence of the cations keep thesame.
文摘In order to study the effect of fused spinel on the properties of phosphoricacid bonded high alumina castables, samples with different contents of fused spinel were prepared.The results show that when the contents of the fused spinel are between 8% and 16% (mass fraction),the castables have good properties. The castables overcome the shortages of the phosphoric acidbonded high alumina castables with bauxite cement as a hardening promoter. The experimentsdemonstrate that most of the service properties of the castables with fused spinel are better thanthose of the normal phosphoric acid bonded castables which use bauxite cement as a hardeningpromoter. The examination of the materials indicates that free MgO inclusions in the spinel powdercan promote the hardening of the castables.
文摘AIM To investigate the expression change of α-synuclein in the brain of different age AD-like an-imal model and to explore the pathology mechanism of α-synuclein in neural degeneration and protective effect of 2 kinds of Chinese components. METHODS A generally accepted animal model of Alzheimer' s disease-APP V717I transgenic (Tg) mouse was observed from 4 to 16 month old. The Tg mice wererandomly divided into model group(4 month, 10 month and 16 month old), Shen-wu capsule with the dose of 0.4g and 1.2g/kg/d, 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucoside(TSG), one of effective components in Polygonum muhiflorum, at dose of 0. 05,0.1 and 0.2g/kg/d.
文摘Objective: to explore the improvement of seamless nursing quality and complication rate of elderly patients with coronary heart disease. Methods: from January 2020 to August 2021,100 cases of elderly coronary heart disease admitted to the department of cardiovascular medicine were selected for clinical study and grouped by lottery method. 50 patients with routine care were in the control group, and 50 patients with seamless care were in the observation group. The quality of care with complications in both groups was obtained and compared. Results: the nursing quality score (service attitude, nurse-patient relationship, psychological counseling, knowledge education, nursing safety, and self-feeling) of the observation group was significantly higher than that of the control group (P 0.05). The complication rate in the observation group of 4.00% was significantly less than 18.00% in the control group (P 0.05). Conclusion: seamless nursing during treatment can improve the quality of clinical care, reduce the incidence of complications and have significant promotion value.
