AIM： To investigate the anti-fibrosis effect of the tissue transglutarninase （tTG） specific inhibitor cystarnine on liver fibrosis. METHODS： Sixty-eight male Sprague Dawley rats were divided into three groups： no...AIM： To investigate the anti-fibrosis effect of the tissue transglutarninase （tTG） specific inhibitor cystarnine on liver fibrosis. METHODS： Sixty-eight male Sprague Dawley rats were divided into three groups： normal control, liver fibrosis control and cystamine-treated group. Liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride （CCl4）, and Cystarnine was administrated by intraperitoneal injection starting 2 d before the first administration of CCl4. Animals in each group were further divided into 2 subgroups according to two time points of 4 wk and 8 wk after treatment. Hepatic function, pathological evaluation （semi-quantitative scoring system, SSS） and liver hydroxyproline （Hyp） content were examined. Real-time PCR was used to detect the expression of tTG, smooth muscle alpha actin （α-SMA）, tissue inhibitor of metalloproteinase 1 （TIMP-1） and collagen-1 mRNA. The expressions of tTG and α-SMA protein were detected by Western Blotting. RESULTS： Eight weeks after treatment, the SSS score of liver was significantly less in the cystamine group than that in the fibrosis control group （P 〈 0.01）. The levels of alanine arninotransferase （ALT） and total bile acid （TBA） at the 4 wk and 8 wk time points were decreased in the cystamine group compared with those in fibrosis controls （P 〈 0.01）. Liver hydroxyproline content at the 4 wk and 8 wk time points showed a substantial reduction in the cystamine group compared to fibrosis controls （P 〈 0.01）. The expression of tTG, α-SMA, collagen-1, TIMP-1 mRNA and tTG, as well as α-SMA protein was downregulated in the cystamine group compared to fibrosis controls. CONCLUSION： Cystamine can ameliorate CCl4 induced liver fibrosis and protect hepatic function. The possible mechanism is related to the reduced synthesis of the extracellular matrix （ECM） caused by the inhibition of hepatic stellate cell activation and decreased expression of TIMP-1.展开更多
A series of Mg‐Al mixed oxide catalysts are prepared and introduced as efficient irreducible catalysts for the oxidative coupling of alcohols and amines to imine.The structure and surface properties of Mg‐Al oxides ...A series of Mg‐Al mixed oxide catalysts are prepared and introduced as efficient irreducible catalysts for the oxidative coupling of alcohols and amines to imine.The structure and surface properties of Mg‐Al oxides are modulated by changing the Mg/Al ratios,calcination temperature and treatment with probe molecules.Detailed characterization,including X‐ray diffraction,27Al magic angle spinning nuclear magnetic resonance spectroscopy,N2‐adsorption,NH3‐temperature‐programmed desorption,CO2‐temperature‐programmed desorption and X‐ray photoelectron spectroscopy are carried out to determine the physicochemical properties of these catalysts.The Mg‐Al oxides with Mg/Al=3exhibit the highest activity in the reaction,which possess a large number of surface weak basic sites and a relatively small number of weak acidic sites.The role of the acidic and basic sites in the reaction process is systematically investigated,and are shown to serve as adsorption and activation sites for amines and alcohols,respectively.Under the synergistic effect of these acid‐base centers,the oxidative coupling process successfully occurs on the surface of Mg‐Al mixed oxides.Compared with the acidic sites,the weak basic sites play a more important role in the catalytic process.The acidic sites are the catalytic centers for the benzyl alcohol activation,which control the reaction rate of the oxidative coupling reaction.展开更多
Based on the measurement of dispersion characteristic and birefractive index of the fluorinated polyimide film,a statistical optimum design method is proposed and used to realize the design of 32- and 36-wavelengths o...Based on the measurement of dispersion characteristic and birefractive index of the fluorinated polyimide film,a statistical optimum design method is proposed and used to realize the design of 32- and 36-wavelengths optical waveguide wavelength-interleave coupler(i,e.,interleaver) with the optimization of polarization fluctuation and wavelength interval of 0.8 nm at 1 550 nm.The largest cross coupling ratios of the two interleavers are respectively less than 1.8% and 3.5%,while the least through coupling ratios are respectively greater than 98.2% and 96.5%.The output differences due to polarization fluctuation are less than ±1.7% and ±3.2%.展开更多
The hydrotalcite-like compound [Zn2Al·（OH）6] NO3·nH2O and [Mg2Al·（OH）6] NO3·nH2O （shorted as ZnA1-NO3 and MgAl-NO3） was intercalated with the chelating agent EDTA （Ethylenediaminetetraacetic...The hydrotalcite-like compound [Zn2Al·（OH）6] NO3·nH2O and [Mg2Al·（OH）6] NO3·nH2O （shorted as ZnA1-NO3 and MgAl-NO3） was intercalated with the chelating agent EDTA （Ethylenediaminetetraacetic Acid） and EDDS （N, N＇-1, 2-Ethanediylbis-1-Aspartic Acid） by anion exchange. The materials synthesized in this work were characterized by chemical analysis, FT-IR （Fourier Transform Infrared Spectroscopy）, SEM （Scanning Electron Microscopy） and XRD （Powder X-ray Diffraction） to confirm their properties. In order to discuss the adsorption capacity of LDHs （Layered Double Hydroxides）, the adsorption experiment was investigated under the optimum condition （10 mg, 25℃ and 100 μg·L-1）. The amount of metallic ions adsorbed by LDHs intercalated with EDTA and precursor LDHs were determined by ICP-AES （Inductively Coupled Plasma-Atomic Emission Spectrometry） and AAS （Atomic Absorption Spectrometry）. The intercalation of EDTA leads to improve the adsorption capacity of LDHs. LDHs intercalated with chelating agents have generally high affinity for removing metallic ions, and they can be efficient adsorbents for metallic ions.展开更多
The oxidative coupling of methylarenes and N,N-dialkylformamides was developed, and the appropriate reaction conditions were established. By using I2 as the catalyst, and tert-butyl hydroperoxide(TBHP) as the oxidant,...The oxidative coupling of methylarenes and N,N-dialkylformamides was developed, and the appropriate reaction conditions were established. By using I2 as the catalyst, and tert-butyl hydroperoxide(TBHP) as the oxidant, the reaction provided N,N-dialkylamides or N-alkylamides with moderate yields via multiple sp3 C-H bonds activation of methylarenes in aqueous and metal-free conditions.展开更多
A wavelength dispersive X-ray fluorescence （WD-XRF） spectrometry combined with calibration curve method was estab- lished for simultaneously analyzing low-Z elements （C, N, O） and A1, Si, Fe in polyamide. To inves...A wavelength dispersive X-ray fluorescence （WD-XRF） spectrometry combined with calibration curve method was estab- lished for simultaneously analyzing low-Z elements （C, N, O） and A1, Si, Fe in polyamide. To investigate the origin of plastic material causing deposition and blocking in instrument engines and pipelines, polyamide 6 （PA 6, an engineering plastic） was chosen as the study object on account of its common use in industry. The sample preparation with pressed powder disk has been developed for determination of six elements in PA 6. Pure Cu metal was used as the matrix and PA 6 was regarded as standard sample for C, N, O elements. PA 6 particles were firstly smashed to uniform powder in liquid nitrogen, and then mixed with inorganic standard powders （Fe203, A1203, SIO2, and Na2SiO3）. The mixture was ground to obtain homogeneous calibration materials for WD-XRF analysis. The quantitative property of the calibration curve method for each element was re- liable. The limits of detection （S/N≤3） of C, N, O, A1, Si and Fe using WD-XRF were 249, 120, 101, 6.2, 3.3, and 1.8 μg/g, respectively. To confirm the accuracy of the proposed WD-XRF calibration curve method, inductively coupled plasma optical emission spectroscopy （ICP-OES） detection for A1, Si, Fe and elemental analyzer （EA） analysis for C, N, O were utilized. A good correlation of the WD-XRF results with the measurements of ICP-OES and EA was observed.展开更多
基金Supported by National Natural Science Foundation of China,No. 30571825
文摘AIM： To investigate the anti-fibrosis effect of the tissue transglutarninase （tTG） specific inhibitor cystarnine on liver fibrosis. METHODS： Sixty-eight male Sprague Dawley rats were divided into three groups： normal control, liver fibrosis control and cystamine-treated group. Liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride （CCl4）, and Cystarnine was administrated by intraperitoneal injection starting 2 d before the first administration of CCl4. Animals in each group were further divided into 2 subgroups according to two time points of 4 wk and 8 wk after treatment. Hepatic function, pathological evaluation （semi-quantitative scoring system, SSS） and liver hydroxyproline （Hyp） content were examined. Real-time PCR was used to detect the expression of tTG, smooth muscle alpha actin （α-SMA）, tissue inhibitor of metalloproteinase 1 （TIMP-1） and collagen-1 mRNA. The expressions of tTG and α-SMA protein were detected by Western Blotting. RESULTS： Eight weeks after treatment, the SSS score of liver was significantly less in the cystamine group than that in the fibrosis control group （P 〈 0.01）. The levels of alanine arninotransferase （ALT） and total bile acid （TBA） at the 4 wk and 8 wk time points were decreased in the cystamine group compared with those in fibrosis controls （P 〈 0.01）. Liver hydroxyproline content at the 4 wk and 8 wk time points showed a substantial reduction in the cystamine group compared to fibrosis controls （P 〈 0.01）. The expression of tTG, α-SMA, collagen-1, TIMP-1 mRNA and tTG, as well as α-SMA protein was downregulated in the cystamine group compared to fibrosis controls. CONCLUSION： Cystamine can ameliorate CCl4 induced liver fibrosis and protect hepatic function. The possible mechanism is related to the reduced synthesis of the extracellular matrix （ECM） caused by the inhibition of hepatic stellate cell activation and decreased expression of TIMP-1.
文摘A series of Mg‐Al mixed oxide catalysts are prepared and introduced as efficient irreducible catalysts for the oxidative coupling of alcohols and amines to imine.The structure and surface properties of Mg‐Al oxides are modulated by changing the Mg/Al ratios,calcination temperature and treatment with probe molecules.Detailed characterization,including X‐ray diffraction,27Al magic angle spinning nuclear magnetic resonance spectroscopy,N2‐adsorption,NH3‐temperature‐programmed desorption,CO2‐temperature‐programmed desorption and X‐ray photoelectron spectroscopy are carried out to determine the physicochemical properties of these catalysts.The Mg‐Al oxides with Mg/Al=3exhibit the highest activity in the reaction,which possess a large number of surface weak basic sites and a relatively small number of weak acidic sites.The role of the acidic and basic sites in the reaction process is systematically investigated,and are shown to serve as adsorption and activation sites for amines and alcohols,respectively.Under the synergistic effect of these acid‐base centers,the oxidative coupling process successfully occurs on the surface of Mg‐Al mixed oxides.Compared with the acidic sites,the weak basic sites play a more important role in the catalytic process.The acidic sites are the catalytic centers for the benzyl alcohol activation,which control the reaction rate of the oxidative coupling reaction.
文摘Based on the measurement of dispersion characteristic and birefractive index of the fluorinated polyimide film,a statistical optimum design method is proposed and used to realize the design of 32- and 36-wavelengths optical waveguide wavelength-interleave coupler(i,e.,interleaver) with the optimization of polarization fluctuation and wavelength interval of 0.8 nm at 1 550 nm.The largest cross coupling ratios of the two interleavers are respectively less than 1.8% and 3.5%,while the least through coupling ratios are respectively greater than 98.2% and 96.5%.The output differences due to polarization fluctuation are less than ±1.7% and ±3.2%.
文摘The hydrotalcite-like compound [Zn2Al·（OH）6] NO3·nH2O and [Mg2Al·（OH）6] NO3·nH2O （shorted as ZnA1-NO3 and MgAl-NO3） was intercalated with the chelating agent EDTA （Ethylenediaminetetraacetic Acid） and EDDS （N, N＇-1, 2-Ethanediylbis-1-Aspartic Acid） by anion exchange. The materials synthesized in this work were characterized by chemical analysis, FT-IR （Fourier Transform Infrared Spectroscopy）, SEM （Scanning Electron Microscopy） and XRD （Powder X-ray Diffraction） to confirm their properties. In order to discuss the adsorption capacity of LDHs （Layered Double Hydroxides）, the adsorption experiment was investigated under the optimum condition （10 mg, 25℃ and 100 μg·L-1）. The amount of metallic ions adsorbed by LDHs intercalated with EDTA and precursor LDHs were determined by ICP-AES （Inductively Coupled Plasma-Atomic Emission Spectrometry） and AAS （Atomic Absorption Spectrometry）. The intercalation of EDTA leads to improve the adsorption capacity of LDHs. LDHs intercalated with chelating agents have generally high affinity for removing metallic ions, and they can be efficient adsorbents for metallic ions.
基金This work was supported by the National Natural Science Foundation of China(21272117,20972068)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘The oxidative coupling of methylarenes and N,N-dialkylformamides was developed, and the appropriate reaction conditions were established. By using I2 as the catalyst, and tert-butyl hydroperoxide(TBHP) as the oxidant, the reaction provided N,N-dialkylamides or N-alkylamides with moderate yields via multiple sp3 C-H bonds activation of methylarenes in aqueous and metal-free conditions.
基金supported by the Research Fund for the Doctoral Program of Higher Education (20110002110052)
文摘A wavelength dispersive X-ray fluorescence （WD-XRF） spectrometry combined with calibration curve method was estab- lished for simultaneously analyzing low-Z elements （C, N, O） and A1, Si, Fe in polyamide. To investigate the origin of plastic material causing deposition and blocking in instrument engines and pipelines, polyamide 6 （PA 6, an engineering plastic） was chosen as the study object on account of its common use in industry. The sample preparation with pressed powder disk has been developed for determination of six elements in PA 6. Pure Cu metal was used as the matrix and PA 6 was regarded as standard sample for C, N, O elements. PA 6 particles were firstly smashed to uniform powder in liquid nitrogen, and then mixed with inorganic standard powders （Fe203, A1203, SIO2, and Na2SiO3）. The mixture was ground to obtain homogeneous calibration materials for WD-XRF analysis. The quantitative property of the calibration curve method for each element was re- liable. The limits of detection （S/N≤3） of C, N, O, A1, Si and Fe using WD-XRF were 249, 120, 101, 6.2, 3.3, and 1.8 μg/g, respectively. To confirm the accuracy of the proposed WD-XRF calibration curve method, inductively coupled plasma optical emission spectroscopy （ICP-OES） detection for A1, Si, Fe and elemental analyzer （EA） analysis for C, N, O were utilized. A good correlation of the WD-XRF results with the measurements of ICP-OES and EA was observed.
