AIM To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome, and establish a new sequencing method in China. METHODS Polymerase Chain Reaction (PCR) was combined with DNA sequencing techn...AIM To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome, and establish a new sequencing method in China. METHODS Polymerase Chain Reaction (PCR) was combined with DNA sequencing technique. PCR products were purified by agarose gel electrophoresis, polyacrylamide gel electrophoresis (PAGE), Polyethylene glycol (PEG) respectively. Then in the presence of a 5′ labeling PCR primer, purified PCR products were directly sequenced. By this method, HCV NS5b cDNA from two HCV infected individuals (HC 42 and HC 49) were sequenced.展开更多
Polycarbosilane containing beryllium(BPCS) precursors was prepared by the reaction of polycarbosilane(PCS) with beryllium acetylacetone(Be(acac)2).The analysis of structures and components of BPCS demonstrates that th...Polycarbosilane containing beryllium(BPCS) precursors was prepared by the reaction of polycarbosilane(PCS) with beryllium acetylacetone(Be(acac)2).The analysis of structures and components of BPCS demonstrates that their main structures are basically the same as PCS.Ceramization of BPCS precursors shows that BPCS precursors are organic below 600 °C and inorganic at 800 °C.At 1400 °C,BPCS precursors convert into silicon carbide ceramics.The ceramization of different beryllium content precursors were studied,which show that beryllium plays an important role in the inhibition of crystalline grain growth of β-SiC at high temperature and it can adjust the dielectric constant of silicon carbide ceramics.展开更多
A two-component waterborne polyurethane(2K-WPU) was prepared by mixing water-soluble acrylic resin and hexamethylene diisocyanate biuret, and then diluted for phase inversion with water. Compared with water-soluble ac...A two-component waterborne polyurethane(2K-WPU) was prepared by mixing water-soluble acrylic resin and hexamethylene diisocyanate biuret, and then diluted for phase inversion with water. Compared with water-soluble acrylic resin, the phase inversion of 2K-WPU occurs at lower water content. It is indicated by TEM that 2K-WPU parti-cles show a core-shell structure, in which HDI biuret is encapsulated by hydrophilic acrylic resin. 2K-WPU emulsion with HDI biuret has larger particle size and narrower distribution index, while for 2K-WPU emulsion with HDI iso-cyanurate, the latex not only has large particle size, but also has two-peak distribution. FTIR shows that the reaction be-tween HDI biuret and acrylic resin can complete in 12h. In addition, studies on effect of composition of acrylic resin on performance of 2K-WPU show that narrowing the polar difference between water-soluble acrylic resin and HDI biuret and improving the miscibility of two components are the key to prepare the transparent and high gloss films with high crosslinking density.展开更多
Turbot Scophthalmus maximus, an important aquaculture species in China, currently suffers from epizootic diseases because of high density aquaculture. Enrofloxacin has been used to treat various systemic bacterial fis...Turbot Scophthalmus maximus, an important aquaculture species in China, currently suffers from epizootic diseases because of high density aquaculture. Enrofloxacin has been used to treat various systemic bacterial fish infections. However, studies concerning the pharmacokinetics of enrofloxacin in turbot are limited. In this study, the pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin, were investigated in the turbot following intravenous and oral administration at 10 mg enrofloxacin/kg body weight, at 16℃ and 10℃ water temperatures. The concentrations of enrofloxacin and ciprofloxacin in the main tissues （plasma, muscle, liver and kidney） were detected by HPLC. The results show that the plasma concentration-time data for enrofloxacin were best described as a two-compartment open model after intravenous and oral administration. Three pharmacokinetic equations were established between the concentrations and temperatures. The kinetic profile of enrofloxacin was temperature dependent. The absorption half-life of enrofloxacin was 1.99 h and 2.17 h after oral administration, whereas the elimination half-life of the drug was 98.63 h and 136.59 h at 16℃ and 10℃, respectively. The peak concentration of enrofloxacin in plasma and tissues was higher at 16℃ than that at 10℃, and the peak plasma concentration time in the liver was the shortest at both temperatures among those of other tissues. The plasma ℃/MIC ratio varied between 11.08 and 5 540.00 at 16℃; and between 7.92 and 3 960.00 at 10℃. The AUC/MIC ratio was 467.82-280 690.00 at 16℃, and 359.48-215 690.00 at 10℃. These ratios indicate that it is possible to obtain therapeutic efficacy. Very low levels of ciprofloxacin were detected. The AUC ratios of ciprofloxacin and enrofloxacin in plasma suggest that plasma ciprofloxacin might play a minor role in enrofloxacin treatment for turbot.展开更多
Poly(D,L-lactide) was synthesized by indirect method from D,L-lactic acid and characterized by infrared spectrum and proton nuclear magnetic resonance. The influences of monomer purity, initiator concentration, polyme...Poly(D,L-lactide) was synthesized by indirect method from D,L-lactic acid and characterized by infrared spectrum and proton nuclear magnetic resonance. The influences of monomer purity, initiator concentration, polymerization temperature and polymerization time on the relative molecular mass of poly(D, L-lactide) were investigated. The polylactide was made into porous materials by using solvent-casting particulate-leaching method. Under the optimized conditions, polylactides with a viscosity average molecular mass up to 1.82×105 are obtained and the results are fairly reproducible. Scanning electron microscope observation indicates that the sample is highly porous and well-distributed with good interconnections between pores and the pore size of porous materials is in the range from 200 μm to 500 μm and it can be used as scaffold for bone tissue engineering.展开更多
AIM: To evaluate the epidemiological, clinical, laboratory and histological variables capable of predicting the progression of hepatic structural disturbances in chronic hepatitis C patients during the time interval b...AIM: To evaluate the epidemiological, clinical, laboratory and histological variables capable of predicting the progression of hepatic structural disturbances in chronic hepatitis C patients during the time interval between two liver biopsies. METHODS: Clinical charts of 112 chronic hepatitis C patients were retrospectively analyzed, whereas liver biopsies were revised. Immunohistochemical detection of interferon receptor was based on the Envision-Peroxidase System. RESULTS: In the multivariate analysis, the variables in the age at first biopsy, ALT levels, presence of lymphoid aggregates and siderosis were the determinants of the best model for predicting the severity of the disease. The direct progression rate of hepatic structural lesions was significantly higher in untreated patients, intermediate in treated non-responders and lower in treated responders to antiviral therapy (non-treated vs responders, 0.22 ± 0.50 vs -0.15 ± 0.46, P = 0.0053). Immuno-expression of interferon receptor is not a relevant factor. CONCLUSION: The best predictors of the progression of fibrosis are age at the first liver biopsy, extent of ALT elevation, inflammation at liver histology and hepatic siderosis. Antiviral treatment is effective in preventing the progression of liver structural lesions in chronic hepatitis C patients.展开更多
AIM： To determine the most frequent etiologies of hepatic epithelioid granulomas, and whether there was an association with chronic hepatitis C virus （HCV）. METHODS： Both a retrospective review of the pathol- ogy ...AIM： To determine the most frequent etiologies of hepatic epithelioid granulomas, and whether there was an association with chronic hepatitis C virus （HCV）. METHODS： Both a retrospective review of the pathol- ogy database of liver biopsies at our institution from 1996 through 2006 as well as data from a prospective study of hepatic fibrosis markers and liver biopsies from 2003 to 2006 were reviewed to identify cases of hepatic epithelioid granulomas. Appropriate charts, liver biopsy slides, and laboratory data were reviewed to determine all possible associations. The diagnosis of HCV was based on a positive HCV RNA. RESULTS： There were 4578 liver biopsies and 36 （0.79%） had at least one epithelioid granuloma. HCV was the most common association. Fourteen patients had HCV, and in nine, there were no concurrent condi- tions known to be associated with hepatic granulomas. Prior interferon therapy and crystalloid substances from illicit intravenous injections did not account for the finding. There were hepatic epithelioid granulomas in 3 of 241 patients （1.24%） with known chronic HCV enrolled in the prospective study of hepatic fibrosis markers. CONCLUSION： Although uncommon, hepatic granu- Iomas may be part of the histological spectrum of chronic HCV. When epithelioid granulomas are found on the liver biopsy of someone with HCV, other clini- cally appropriate studies should be done, but if nothing else is found, the clinician can be comfortable with an HCV association.展开更多
A series of Zn–Ca–Al oxides with different CaO and ZnO contents have been prepared and evaluated in the synthesis of propylene carbonate(PC) from 1,2-propylene glycol(PG) and urea in a batch reactor. The effect of c...A series of Zn–Ca–Al oxides with different CaO and ZnO contents have been prepared and evaluated in the synthesis of propylene carbonate(PC) from 1,2-propylene glycol(PG) and urea in a batch reactor. The effect of catalyst composition, basicity and reaction process parameters such as temperature, catalyst dose, molar ratio of PG to urea, purge gas flow and reaction time has been studied to find suitable reaction conditions for the PC synthesis. The PC selectivity and yield under the desired conditions could reach 98.4% and 90.8%, respectively. The best performing catalyst also exhibited a good reusability without appreciable loss in the PC selectivity and yield after five consecutive reaction runs. In addition, a stepwise reaction pathway involving a 2-hydroxypropyl carbamate intermediate was proposed for the urea alcoholysis to PC in the presence of Zn–Ca–Al catalysts, according to the time dependences of reaction intermediates and products.展开更多
AIM:To analyze the correlation between CD14 rs2569190/C-159T single nucleotide polymorphism (SNP) and disease progression in chronic hepatitis C.METHODS: Liver biopsy specimens from a total of 137 and 349 patients wit...AIM:To analyze the correlation between CD14 rs2569190/C-159T single nucleotide polymorphism (SNP) and disease progression in chronic hepatitis C.METHODS: Liver biopsy specimens from a total of 137 and 349 patients with chronic hepatitis C were separately evaluated with respect to necroinflammatory activity (grading) and architectural changes (staging). In one group, further histological lesions characteristic for hepatitis C, hepatitis C virus subtypes, and biochemical parameters of liver disease were also investigated. Samples of genomic DNA were genotyped for the respective SNP by 5'-nuclease assays using fluorescent dye-labeled allele-specif ic probes.RESULTS: Genotype distribution did not deviate from the Hardy-Weinberg equilibrium. In the first group, patients homozygous for the variant allele T were found to be younger than C allele carriers (39.6±12.5 vs 45.7±11.5, P=0.008). Among the histological lesions studied, portal lymphoid aggregates were more frequently observed among TT homozygotes than among C carriers (21/37 vs 32/100, P=0.008). The presence of portal lymphoid aggregates was closely correlated with hepatic inflammation (P=0.003) and with bile duct damage (P<0.001). The degree of fibrosis, in contrast, was not found to be related to the CD14 gene C-159T polymorphism.CONCLUSION: The data suggest a possible relationship between CD14 C-159T polymorphism and the formation of portal lymphoid aggregates, but not liver fibrosis progression in chronic hepatitis C.展开更多
文摘AIM To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome, and establish a new sequencing method in China. METHODS Polymerase Chain Reaction (PCR) was combined with DNA sequencing technique. PCR products were purified by agarose gel electrophoresis, polyacrylamide gel electrophoresis (PAGE), Polyethylene glycol (PEG) respectively. Then in the presence of a 5′ labeling PCR primer, purified PCR products were directly sequenced. By this method, HCV NS5b cDNA from two HCV infected individuals (HC 42 and HC 49) were sequenced.
基金Project(51074193)supported by the National Natural Science Foundation of ChinaProjects(2011AA7024034,2011AA7053016)supported by the National High Technology Research and Development Program of ChinaProject(LK0903)supported by State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University,China
文摘Polycarbosilane containing beryllium(BPCS) precursors was prepared by the reaction of polycarbosilane(PCS) with beryllium acetylacetone(Be(acac)2).The analysis of structures and components of BPCS demonstrates that their main structures are basically the same as PCS.Ceramization of BPCS precursors shows that BPCS precursors are organic below 600 °C and inorganic at 800 °C.At 1400 °C,BPCS precursors convert into silicon carbide ceramics.The ceramization of different beryllium content precursors were studied,which show that beryllium plays an important role in the inhibition of crystalline grain growth of β-SiC at high temperature and it can adjust the dielectric constant of silicon carbide ceramics.
文摘A two-component waterborne polyurethane(2K-WPU) was prepared by mixing water-soluble acrylic resin and hexamethylene diisocyanate biuret, and then diluted for phase inversion with water. Compared with water-soluble acrylic resin, the phase inversion of 2K-WPU occurs at lower water content. It is indicated by TEM that 2K-WPU parti-cles show a core-shell structure, in which HDI biuret is encapsulated by hydrophilic acrylic resin. 2K-WPU emulsion with HDI biuret has larger particle size and narrower distribution index, while for 2K-WPU emulsion with HDI iso-cyanurate, the latex not only has large particle size, but also has two-peak distribution. FTIR shows that the reaction be-tween HDI biuret and acrylic resin can complete in 12h. In addition, studies on effect of composition of acrylic resin on performance of 2K-WPU show that narrowing the polar difference between water-soluble acrylic resin and HDI biuret and improving the miscibility of two components are the key to prepare the transparent and high gloss films with high crosslinking density.
基金Supported by the National Natural Science Foundation of China(Nos.30700617,31101298)the National Special Research Fund for NonProfit Sector(No.nyhyzx07-046)
文摘Turbot Scophthalmus maximus, an important aquaculture species in China, currently suffers from epizootic diseases because of high density aquaculture. Enrofloxacin has been used to treat various systemic bacterial fish infections. However, studies concerning the pharmacokinetics of enrofloxacin in turbot are limited. In this study, the pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin, were investigated in the turbot following intravenous and oral administration at 10 mg enrofloxacin/kg body weight, at 16℃ and 10℃ water temperatures. The concentrations of enrofloxacin and ciprofloxacin in the main tissues （plasma, muscle, liver and kidney） were detected by HPLC. The results show that the plasma concentration-time data for enrofloxacin were best described as a two-compartment open model after intravenous and oral administration. Three pharmacokinetic equations were established between the concentrations and temperatures. The kinetic profile of enrofloxacin was temperature dependent. The absorption half-life of enrofloxacin was 1.99 h and 2.17 h after oral administration, whereas the elimination half-life of the drug was 98.63 h and 136.59 h at 16℃ and 10℃, respectively. The peak concentration of enrofloxacin in plasma and tissues was higher at 16℃ than that at 10℃, and the peak plasma concentration time in the liver was the shortest at both temperatures among those of other tissues. The plasma ℃/MIC ratio varied between 11.08 and 5 540.00 at 16℃; and between 7.92 and 3 960.00 at 10℃. The AUC/MIC ratio was 467.82-280 690.00 at 16℃, and 359.48-215 690.00 at 10℃. These ratios indicate that it is possible to obtain therapeutic efficacy. Very low levels of ciprofloxacin were detected. The AUC ratios of ciprofloxacin and enrofloxacin in plasma suggest that plasma ciprofloxacin might play a minor role in enrofloxacin treatment for turbot.
基金Project(50174059) supported by the National Natural Science Foundation of China
文摘Poly(D,L-lactide) was synthesized by indirect method from D,L-lactic acid and characterized by infrared spectrum and proton nuclear magnetic resonance. The influences of monomer purity, initiator concentration, polymerization temperature and polymerization time on the relative molecular mass of poly(D, L-lactide) were investigated. The polylactide was made into porous materials by using solvent-casting particulate-leaching method. Under the optimized conditions, polylactides with a viscosity average molecular mass up to 1.82×105 are obtained and the results are fairly reproducible. Scanning electron microscope observation indicates that the sample is highly porous and well-distributed with good interconnections between pores and the pore size of porous materials is in the range from 200 μm to 500 μm and it can be used as scaffold for bone tissue engineering.
基金Supported by Alves de Queiroz Family Fund for Research
文摘AIM: To evaluate the epidemiological, clinical, laboratory and histological variables capable of predicting the progression of hepatic structural disturbances in chronic hepatitis C patients during the time interval between two liver biopsies. METHODS: Clinical charts of 112 chronic hepatitis C patients were retrospectively analyzed, whereas liver biopsies were revised. Immunohistochemical detection of interferon receptor was based on the Envision-Peroxidase System. RESULTS: In the multivariate analysis, the variables in the age at first biopsy, ALT levels, presence of lymphoid aggregates and siderosis were the determinants of the best model for predicting the severity of the disease. The direct progression rate of hepatic structural lesions was significantly higher in untreated patients, intermediate in treated non-responders and lower in treated responders to antiviral therapy (non-treated vs responders, 0.22 ± 0.50 vs -0.15 ± 0.46, P = 0.0053). Immuno-expression of interferon receptor is not a relevant factor. CONCLUSION: The best predictors of the progression of fibrosis are age at the first liver biopsy, extent of ALT elevation, inflammation at liver histology and hepatic siderosis. Antiviral treatment is effective in preventing the progression of liver structural lesions in chronic hepatitis C patients.
基金Supported by The grant from the National Center for Research Resources, NIH, USPHS, No. M01 RR 00073
文摘AIM： To determine the most frequent etiologies of hepatic epithelioid granulomas, and whether there was an association with chronic hepatitis C virus （HCV）. METHODS： Both a retrospective review of the pathol- ogy database of liver biopsies at our institution from 1996 through 2006 as well as data from a prospective study of hepatic fibrosis markers and liver biopsies from 2003 to 2006 were reviewed to identify cases of hepatic epithelioid granulomas. Appropriate charts, liver biopsy slides, and laboratory data were reviewed to determine all possible associations. The diagnosis of HCV was based on a positive HCV RNA. RESULTS： There were 4578 liver biopsies and 36 （0.79%） had at least one epithelioid granuloma. HCV was the most common association. Fourteen patients had HCV, and in nine, there were no concurrent condi- tions known to be associated with hepatic granulomas. Prior interferon therapy and crystalloid substances from illicit intravenous injections did not account for the finding. There were hepatic epithelioid granulomas in 3 of 241 patients （1.24%） with known chronic HCV enrolled in the prospective study of hepatic fibrosis markers. CONCLUSION： Although uncommon, hepatic granu- Iomas may be part of the histological spectrum of chronic HCV. When epithelioid granulomas are found on the liver biopsy of someone with HCV, other clini- cally appropriate studies should be done, but if nothing else is found, the clinician can be comfortable with an HCV association.
基金Supported by the Changcheng Scholars Program of Beijing(CIT&TCD 20150316)
文摘A series of Zn–Ca–Al oxides with different CaO and ZnO contents have been prepared and evaluated in the synthesis of propylene carbonate(PC) from 1,2-propylene glycol(PG) and urea in a batch reactor. The effect of catalyst composition, basicity and reaction process parameters such as temperature, catalyst dose, molar ratio of PG to urea, purge gas flow and reaction time has been studied to find suitable reaction conditions for the PC synthesis. The PC selectivity and yield under the desired conditions could reach 98.4% and 90.8%, respectively. The best performing catalyst also exhibited a good reusability without appreciable loss in the PC selectivity and yield after five consecutive reaction runs. In addition, a stepwise reaction pathway involving a 2-hydroxypropyl carbamate intermediate was proposed for the urea alcoholysis to PC in the presence of Zn–Ca–Al catalysts, according to the time dependences of reaction intermediates and products.
基金Supported by A grant of the Deutsche Forschungsgemeinschaft MI 474/1-1Askar E was supported by a scholarship from Damascus University,Syria
文摘AIM:To analyze the correlation between CD14 rs2569190/C-159T single nucleotide polymorphism (SNP) and disease progression in chronic hepatitis C.METHODS: Liver biopsy specimens from a total of 137 and 349 patients with chronic hepatitis C were separately evaluated with respect to necroinflammatory activity (grading) and architectural changes (staging). In one group, further histological lesions characteristic for hepatitis C, hepatitis C virus subtypes, and biochemical parameters of liver disease were also investigated. Samples of genomic DNA were genotyped for the respective SNP by 5'-nuclease assays using fluorescent dye-labeled allele-specif ic probes.RESULTS: Genotype distribution did not deviate from the Hardy-Weinberg equilibrium. In the first group, patients homozygous for the variant allele T were found to be younger than C allele carriers (39.6±12.5 vs 45.7±11.5, P=0.008). Among the histological lesions studied, portal lymphoid aggregates were more frequently observed among TT homozygotes than among C carriers (21/37 vs 32/100, P=0.008). The presence of portal lymphoid aggregates was closely correlated with hepatic inflammation (P=0.003) and with bile duct damage (P<0.001). The degree of fibrosis, in contrast, was not found to be related to the CD14 gene C-159T polymorphism.CONCLUSION: The data suggest a possible relationship between CD14 C-159T polymorphism and the formation of portal lymphoid aggregates, but not liver fibrosis progression in chronic hepatitis C.
