This paper presents the pollen data from deep_sea sediments of station 17962 from the continental slope of the southern South China Sea. The 8 m long profile covers the last 30 000 years including the late stage of Ma...This paper presents the pollen data from deep_sea sediments of station 17962 from the continental slope of the southern South China Sea. The 8 m long profile covers the last 30 000 years including the late stage of Marine Oxygen Isotope Stage 3, the Last Glacial Maximum, the Termination and the Holocene. The pollen results reveal that lowland rainforest covered the emerged southern continental shelf of the South China Sea (Sunda Land) during the last glacial period at low sea level stand. At the same time, upper montane rainforest on the adjacent islands expanded, showing the climate was cooler than that in present day, but no dryness was indicated. The vegetation and climate experienced great fluctuations including abrupt warming and cooling at the end of the ice age. During the Holocene, expansion of mangroves and lowland rainforest, and significant diminution of pollen influx values suggests warming of the climate, rising of the sea level and the submerge of the shelf.展开更多
A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined ...A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined by mass detector. The calibration curve of loratadine was linear within the range of 0.4~100 ng·mL -1 with r=0.9995 . The recovery of this method was within 95%~104%, within day and between day RSD were less than 12%. To study the pharmacokinetics and relative bioavailability of loratadine tablets, two formulations of loratadine tablets were given to 18 healthy male volunteers according to a randomized 2 way cross over design. The C max , AUC 0 t and T max values of the two formulations were 51.89±20.18 ng·mL -1 and 52.48±22.35 ng·mL -1 ; 140.75±88.42 ng·h·mL -1 and 147.24±92.33 ng·h·mL -1 ; 0.81±0.35 h and 0.81±0.27 h respectively. Results from statistic analysis showed that there were no significant difference between the C max , AUC 0-t and T max values of the two formulations. The relative bioavailability of tablets I with respect to tablets II was 97%±13% from the AUC 0 t measurement. Bioequivalance was observed between the two tablets.展开更多
The aim was to research fresh-keeping effects of natamycin on cold-pre- served grape. Red globe grapes were processed with compound coating liquid of chitosan with mass fraction at 1% and natamycin with mass fractions...The aim was to research fresh-keeping effects of natamycin on cold-pre- served grape. Red globe grapes were processed with compound coating liquid of chitosan with mass fraction at 1% and natamycin with mass fractions at 0.20% (T1), 0.40% (T2) and 0.60% (T3), respectively. Grapes processed with water (CK3) and 1% chitosan (CK2) were taken as control groups. Rotten rate, seed shattering rate, mass loss rate, respiratory intensity and related physiological quality in test and control groups were compared. The results indicated that respiratory intensity, mass loss rate, rotten rate and seed shattering rate in CK1 were all higher than those in CK2. In addition, T1, T2 and T3 were lower in the indices than CK1 and CK2, but still kept at a high level in fruit hardness. Furthermore, mass fractions of Vc and titratable acid declined more slowly in T1, T2 and T3, compared with CK1 and CK2. Natamycin better preserved grapes and prolonged storage period. In general, natamycin with mass fraction at 0.4% proved best in fresh-keeping.展开更多
Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil (5-FU) in patients with advanced breast cancer. Methods Twenty...Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil (5-FU) in patients with advanced breast cancer. Methods Twenty-seven patients with breast cancer received repeated doses of 1 255 mg·m^-2 of capecitabine twice daily for 7 d. Blood, tumor, and adjacent healthy tissue samples were collected. The concentrations of capecitabine and its metabolite 5-FU were determined by HPLC. The concentration-time profiles of capecitabine and 5-FU were fitted by pharmacokinetic model. The tissue distribution factors for capecitabine and 5-FU, and the AUC ratios of 5-FU to capecitabine in plasma, tumor or adjacent healthy tissue, were calculated with pharmacokinetic parameters, respectively. Results The Ka of capecitabine was 1.17 h^-1 in plasma, 0. 46 h^-1 in tumor tissue, and 0. 61 h^-1 in healthy tissue. The AUCs of capecitabine were 2. 557 1 μg·mL^-1 ·h, 1. 629 2 μg·g^-1·h and 2. 085 0 μg·g^-1· h, and T1/2 was 0. 782 3 h, 1. 528 1 h and 1. 289 6 h in plasma, tumor, and healthy tissue, respectively. The AUCs of 5-FU were 0.418 7 μg·mL^-1 h, 1.671 7 μg·g^-1·h and 1.020 8 μg·g^-1·h; the T1/2 was 0. 631 3 h ,1.204 1 h and 1.031 2 h in plasma, tumor, and healthy tissue, respectively. The tissue distribution factors of capecitabine were 0. 637 1 in tumor (AUCcap-Tumor/AUCcap-plasma) and 0. 851 4 in healthy tissue (AUCcap-HT/AUCcap-plasma . The tissue distribution factors of 5-FU were 3. 992 6 in tumor (AUC5-FU-Tumor/AUC5-FU-plasma) and 2. 438 0 in healthy tissue (AUC5-FU-HT/AUC5-FU-plasma). The AUC ratios of 5-FU to capecitabine were 0. 1637, 1. 0261, and 0. 489 5 in plasma, tumor, and healthy tissue, respectively. Conclusion The simulation curves for the disposition of capecitabine and its metabolite 5-FU in plasma and tissue basically describe the activation process of capecitabine metabolizing to 5-FU and 5-FU elimination. There are similar distributions for capecitabine in plasma, tumor, and healthy tissue. The exposure of 5-FU in tumor was found to be 3. 992 6 times greater than that in plasma and 2. 438 0 times greater than that in healthy tissue. Capecitabine may metabolize preferentially to 5- FU in tumor tissue after oral administration.展开更多
Tazobactam,β lactamase inhibitor, was synthesized from 6 aminopenicillanic acid through eleven steps, including diazotization, bromination, oxidation, chlorization, cyclization, deprotection and so on. The designed...Tazobactam,β lactamase inhibitor, was synthesized from 6 aminopenicillanic acid through eleven steps, including diazotization, bromination, oxidation, chlorization, cyclization, deprotection and so on. The designed route was examined, particularly the azide substitution and cyclization. In the latter reaction, vinyl acetic ester was employed in place of acetylene.展开更多
Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the mod...Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the model and the pivanampeta-treated groups. The rats or rabbitsin the model group and the pivanampeta-treated group were fed with hypercholesterol diet. Thecarotids of rabbits were cut into pieces and stained with HE. The rat or rabbit serum levels of TC,LDL-CHO, HDL-CHO, IL-8, ET-1, PGI_2, TXA_2, and NO were assayed. The expressions of MCP-1 and IL-8mRNA on rabbit carotid were determined by semi-quantitative RT-PCR. Results Pivanampeta exerted aninhibitory effect on TXA_2 formation without PGI_2 production in the early and later stages ofatherosclerosis. The significantly increased release of NO and the decreased release of IL-8 in theanimals in pivanampeta-treated group were both detected in the rat atherosclerosis model. In therabbit atherosclerosis model the expressions of IL-8 and MCP-1 mRNA in pivanampeta-treated groupwere decreased significantly. However, the treatment with pivanampeta had no effect on the levels ofplasma cholesterol, MDA and SOD. Conclusion The increase of serum NO contents and the decrease ofplasma TXA_2 level, as well as its inhibition of expression of IL-8 and MCP-1 are probably involvedin the mechanisms underlying the anti-atherosclerotic effects of pivanampeta.展开更多
[Objective] Ceftiofur was as the substrate to induce the standard strain of Escherichia coli(E.coli)to be the drug-resistance one.The resistant mechanism of E.coli to ceftiofur was studied.[Method] The sub-inhibitor...[Objective] Ceftiofur was as the substrate to induce the standard strain of Escherichia coli(E.coli)to be the drug-resistance one.The resistant mechanism of E.coli to ceftiofur was studied.[Method] The sub-inhibitory concentration method was used to induce the standard strains C83907 and C83845.After they were induced for 10 generations,the double disc synergy test(DDST),NCCLS(National Committee for Clinical Laboratory Standards)confirmatory test and PCR amplification were used to detect the extend spectrum β-lactamases(ESBLs).The two fold dilution method was used to measure the minimal inhibitory concentration(MIC)of cetiofur to the strain which produced ESBLs.For the drug-resistance strain which produced ESBLs,the two fold dilution method was used to measure the minimal inhibitory concentrations of different proportions of cetiofur and tazobactam sodium.[Result] After they were induced 15 generations,MIC value of ceftiofur to the induced bacteria was during 8-10 μg/ml,and ESBLs was detected.MICs of cetiofur combining tazobactam sodium(the mass ratio was 1∶1-8∶1)to Escherichia coli produced ESBLs reduced 20-22 times than that of cetiofur.[Conclusion] The main mechanism of pathogenic Escherichia coli resistance to ceftiofur was that which produced ESBLs.展开更多
Aim To investigate the relationship between pH environment of meptazinolhydrochloride (MEP) and its nasal absorption. Methods In situ nasal peifusion was performed to studythe effect of pH environment on the nasal abs...Aim To investigate the relationship between pH environment of meptazinolhydrochloride (MEP) and its nasal absorption. Methods In situ nasal peifusion was performed to studythe effect of pH environment on the nasal absorption. Its effect on the transport from nose tobrain was further researched by in vivo experiment. Results In in situ perfusion experiment, thenasal absorption of MEP in basic environment was significantly higher than that in acid condition,but the difference was not observed in in vivo experiment. Conclusion The pH environment ofmeptazinol hydrocloride in formulation cannot be regarded as an important factor influencing nasalabsorption and transport from nose to brain.展开更多
Aim To develop and validate a sensitive and specific liquid chromatography electrospray ionization ion-trap mass spectrometry (LC-ESI-MS/MS) method for the identification and concentration of rupatadine in human pla...Aim To develop and validate a sensitive and specific liquid chromatography electrospray ionization ion-trap mass spectrometry (LC-ESI-MS/MS) method for the identification and concentration of rupatadine in human plasma. Methods After the addition of the internal standard (IS, loratadine) and 0.01 mol·L^-1 sodium hydroxide solution, plasma samples were extracted with methylene chloride: ethyl acetate mixture (20:80, V/V). The organic layer was evaporated under vacuum drying at 37 ℃. The residue was reconstituted with 200 μL mobile phase. Chromatography was performed on an Agilent Eclipse XDB-C18 (4.6 mm × 150 mm, 5 μm) column with a mobile phase consisting of acetonitrile (1% formic acid) -20 mmol·L^-1 ammonium acetate (76:24, V/V) at a flow-rate of 0.6 mL·min^-1. Detection was performed on Agilent MSD Trap XCT ion-trap mass spectrometry connected to a Agilent 1100 high performance liquid chromatography (HPLC) by selected reaction monitoring (SRM) mode via electrospray ionization (ESI) source. Rupatadine (MRM m/z 416 → 309) and loratadine (MRM m/z 383 → 337) were detected by Agilent MSD Trap XCT ion-trap mass analyser. Results The method was proved to be sensitive and specific by testing 20 different plasma batches. Linearity was established for the range of concentrations 0.05 - 14.0 ng·mL^ -1 with a coefficient of determination (r) of 0.998. The intra-and inter-day precision (RSD %) were lower than 15% and accuracy ranged from 85.1% to 114.0%. The lower limit of quantitation (LLOQ) was identifiable and reproducible at 0.05 ng·mL^-1 with a precision of 9.22% (n =5). Conclusion The proposed method is sensitive and reproducible enough to be used in pharmacokinetic, bioavailability or bioequivalence studies of rupatadine.展开更多
A rapid, accurate and sensitive HPLC method for the determination of bupropion hydrochloride in a new tablet formulation is described. Chromatographic separation of bupropion hydrochloride is achieved using a mobile p...A rapid, accurate and sensitive HPLC method for the determination of bupropion hydrochloride in a new tablet formulation is described. Chromatographic separation of bupropion hydrochloride is achieved using a mobile phase consisting of methanol -0.01 mol·L -1 ammonium dihydrogen phosphate (80:20, v/v, pH 4.8) at a flow rate of 1.0 mL·min -1 on a Hypersil BDS C18 column. Absorbance is monitored at 251 nm where bupropion hydrochloride has maximum absorption in the mobile phase. The linear range of determination for bupropion hydrochloride is between 2.12 and 21.2 μg·mL -1. The proposed method was validated with respect to accuracy, precision, limits of detection and quantification and robustness, etc.展开更多
文摘This paper presents the pollen data from deep_sea sediments of station 17962 from the continental slope of the southern South China Sea. The 8 m long profile covers the last 30 000 years including the late stage of Marine Oxygen Isotope Stage 3, the Last Glacial Maximum, the Termination and the Holocene. The pollen results reveal that lowland rainforest covered the emerged southern continental shelf of the South China Sea (Sunda Land) during the last glacial period at low sea level stand. At the same time, upper montane rainforest on the adjacent islands expanded, showing the climate was cooler than that in present day, but no dryness was indicated. The vegetation and climate experienced great fluctuations including abrupt warming and cooling at the end of the ice age. During the Holocene, expansion of mangroves and lowland rainforest, and significant diminution of pollen influx values suggests warming of the climate, rising of the sea level and the submerge of the shelf.
文摘A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined by mass detector. The calibration curve of loratadine was linear within the range of 0.4~100 ng·mL -1 with r=0.9995 . The recovery of this method was within 95%~104%, within day and between day RSD were less than 12%. To study the pharmacokinetics and relative bioavailability of loratadine tablets, two formulations of loratadine tablets were given to 18 healthy male volunteers according to a randomized 2 way cross over design. The C max , AUC 0 t and T max values of the two formulations were 51.89±20.18 ng·mL -1 and 52.48±22.35 ng·mL -1 ; 140.75±88.42 ng·h·mL -1 and 147.24±92.33 ng·h·mL -1 ; 0.81±0.35 h and 0.81±0.27 h respectively. Results from statistic analysis showed that there were no significant difference between the C max , AUC 0-t and T max values of the two formulations. The relative bioavailability of tablets I with respect to tablets II was 97%±13% from the AUC 0 t measurement. Bioequivalance was observed between the two tablets.
文摘The aim was to research fresh-keeping effects of natamycin on cold-pre- served grape. Red globe grapes were processed with compound coating liquid of chitosan with mass fraction at 1% and natamycin with mass fractions at 0.20% (T1), 0.40% (T2) and 0.60% (T3), respectively. Grapes processed with water (CK3) and 1% chitosan (CK2) were taken as control groups. Rotten rate, seed shattering rate, mass loss rate, respiratory intensity and related physiological quality in test and control groups were compared. The results indicated that respiratory intensity, mass loss rate, rotten rate and seed shattering rate in CK1 were all higher than those in CK2. In addition, T1, T2 and T3 were lower in the indices than CK1 and CK2, but still kept at a high level in fruit hardness. Furthermore, mass fractions of Vc and titratable acid declined more slowly in T1, T2 and T3, compared with CK1 and CK2. Natamycin better preserved grapes and prolonged storage period. In general, natamycin with mass fraction at 0.4% proved best in fresh-keeping.
文摘Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil (5-FU) in patients with advanced breast cancer. Methods Twenty-seven patients with breast cancer received repeated doses of 1 255 mg·m^-2 of capecitabine twice daily for 7 d. Blood, tumor, and adjacent healthy tissue samples were collected. The concentrations of capecitabine and its metabolite 5-FU were determined by HPLC. The concentration-time profiles of capecitabine and 5-FU were fitted by pharmacokinetic model. The tissue distribution factors for capecitabine and 5-FU, and the AUC ratios of 5-FU to capecitabine in plasma, tumor or adjacent healthy tissue, were calculated with pharmacokinetic parameters, respectively. Results The Ka of capecitabine was 1.17 h^-1 in plasma, 0. 46 h^-1 in tumor tissue, and 0. 61 h^-1 in healthy tissue. The AUCs of capecitabine were 2. 557 1 μg·mL^-1 ·h, 1. 629 2 μg·g^-1·h and 2. 085 0 μg·g^-1· h, and T1/2 was 0. 782 3 h, 1. 528 1 h and 1. 289 6 h in plasma, tumor, and healthy tissue, respectively. The AUCs of 5-FU were 0.418 7 μg·mL^-1 h, 1.671 7 μg·g^-1·h and 1.020 8 μg·g^-1·h; the T1/2 was 0. 631 3 h ,1.204 1 h and 1.031 2 h in plasma, tumor, and healthy tissue, respectively. The tissue distribution factors of capecitabine were 0. 637 1 in tumor (AUCcap-Tumor/AUCcap-plasma) and 0. 851 4 in healthy tissue (AUCcap-HT/AUCcap-plasma . The tissue distribution factors of 5-FU were 3. 992 6 in tumor (AUC5-FU-Tumor/AUC5-FU-plasma) and 2. 438 0 in healthy tissue (AUC5-FU-HT/AUC5-FU-plasma). The AUC ratios of 5-FU to capecitabine were 0. 1637, 1. 0261, and 0. 489 5 in plasma, tumor, and healthy tissue, respectively. Conclusion The simulation curves for the disposition of capecitabine and its metabolite 5-FU in plasma and tissue basically describe the activation process of capecitabine metabolizing to 5-FU and 5-FU elimination. There are similar distributions for capecitabine in plasma, tumor, and healthy tissue. The exposure of 5-FU in tumor was found to be 3. 992 6 times greater than that in plasma and 2. 438 0 times greater than that in healthy tissue. Capecitabine may metabolize preferentially to 5- FU in tumor tissue after oral administration.
文摘Tazobactam,β lactamase inhibitor, was synthesized from 6 aminopenicillanic acid through eleven steps, including diazotization, bromination, oxidation, chlorization, cyclization, deprotection and so on. The designed route was examined, particularly the azide substitution and cyclization. In the latter reaction, vinyl acetic ester was employed in place of acetylene.
文摘Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the model and the pivanampeta-treated groups. The rats or rabbitsin the model group and the pivanampeta-treated group were fed with hypercholesterol diet. Thecarotids of rabbits were cut into pieces and stained with HE. The rat or rabbit serum levels of TC,LDL-CHO, HDL-CHO, IL-8, ET-1, PGI_2, TXA_2, and NO were assayed. The expressions of MCP-1 and IL-8mRNA on rabbit carotid were determined by semi-quantitative RT-PCR. Results Pivanampeta exerted aninhibitory effect on TXA_2 formation without PGI_2 production in the early and later stages ofatherosclerosis. The significantly increased release of NO and the decreased release of IL-8 in theanimals in pivanampeta-treated group were both detected in the rat atherosclerosis model. In therabbit atherosclerosis model the expressions of IL-8 and MCP-1 mRNA in pivanampeta-treated groupwere decreased significantly. However, the treatment with pivanampeta had no effect on the levels ofplasma cholesterol, MDA and SOD. Conclusion The increase of serum NO contents and the decrease ofplasma TXA_2 level, as well as its inhibition of expression of IL-8 and MCP-1 are probably involvedin the mechanisms underlying the anti-atherosclerotic effects of pivanampeta.
基金Supported by Education Department of Henan Province Item(2006230004)Henan Science and Technology Agency Item(072102130009)~~
文摘[Objective] Ceftiofur was as the substrate to induce the standard strain of Escherichia coli(E.coli)to be the drug-resistance one.The resistant mechanism of E.coli to ceftiofur was studied.[Method] The sub-inhibitory concentration method was used to induce the standard strains C83907 and C83845.After they were induced for 10 generations,the double disc synergy test(DDST),NCCLS(National Committee for Clinical Laboratory Standards)confirmatory test and PCR amplification were used to detect the extend spectrum β-lactamases(ESBLs).The two fold dilution method was used to measure the minimal inhibitory concentration(MIC)of cetiofur to the strain which produced ESBLs.For the drug-resistance strain which produced ESBLs,the two fold dilution method was used to measure the minimal inhibitory concentrations of different proportions of cetiofur and tazobactam sodium.[Result] After they were induced 15 generations,MIC value of ceftiofur to the induced bacteria was during 8-10 μg/ml,and ESBLs was detected.MICs of cetiofur combining tazobactam sodium(the mass ratio was 1∶1-8∶1)to Escherichia coli produced ESBLs reduced 20-22 times than that of cetiofur.[Conclusion] The main mechanism of pathogenic Escherichia coli resistance to ceftiofur was that which produced ESBLs.
文摘Aim To investigate the relationship between pH environment of meptazinolhydrochloride (MEP) and its nasal absorption. Methods In situ nasal peifusion was performed to studythe effect of pH environment on the nasal absorption. Its effect on the transport from nose tobrain was further researched by in vivo experiment. Results In in situ perfusion experiment, thenasal absorption of MEP in basic environment was significantly higher than that in acid condition,but the difference was not observed in in vivo experiment. Conclusion The pH environment ofmeptazinol hydrocloride in formulation cannot be regarded as an important factor influencing nasalabsorption and transport from nose to brain.
文摘Aim To develop and validate a sensitive and specific liquid chromatography electrospray ionization ion-trap mass spectrometry (LC-ESI-MS/MS) method for the identification and concentration of rupatadine in human plasma. Methods After the addition of the internal standard (IS, loratadine) and 0.01 mol·L^-1 sodium hydroxide solution, plasma samples were extracted with methylene chloride: ethyl acetate mixture (20:80, V/V). The organic layer was evaporated under vacuum drying at 37 ℃. The residue was reconstituted with 200 μL mobile phase. Chromatography was performed on an Agilent Eclipse XDB-C18 (4.6 mm × 150 mm, 5 μm) column with a mobile phase consisting of acetonitrile (1% formic acid) -20 mmol·L^-1 ammonium acetate (76:24, V/V) at a flow-rate of 0.6 mL·min^-1. Detection was performed on Agilent MSD Trap XCT ion-trap mass spectrometry connected to a Agilent 1100 high performance liquid chromatography (HPLC) by selected reaction monitoring (SRM) mode via electrospray ionization (ESI) source. Rupatadine (MRM m/z 416 → 309) and loratadine (MRM m/z 383 → 337) were detected by Agilent MSD Trap XCT ion-trap mass analyser. Results The method was proved to be sensitive and specific by testing 20 different plasma batches. Linearity was established for the range of concentrations 0.05 - 14.0 ng·mL^ -1 with a coefficient of determination (r) of 0.998. The intra-and inter-day precision (RSD %) were lower than 15% and accuracy ranged from 85.1% to 114.0%. The lower limit of quantitation (LLOQ) was identifiable and reproducible at 0.05 ng·mL^-1 with a precision of 9.22% (n =5). Conclusion The proposed method is sensitive and reproducible enough to be used in pharmacokinetic, bioavailability or bioequivalence studies of rupatadine.
文摘A rapid, accurate and sensitive HPLC method for the determination of bupropion hydrochloride in a new tablet formulation is described. Chromatographic separation of bupropion hydrochloride is achieved using a mobile phase consisting of methanol -0.01 mol·L -1 ammonium dihydrogen phosphate (80:20, v/v, pH 4.8) at a flow rate of 1.0 mL·min -1 on a Hypersil BDS C18 column. Absorbance is monitored at 251 nm where bupropion hydrochloride has maximum absorption in the mobile phase. The linear range of determination for bupropion hydrochloride is between 2.12 and 21.2 μg·mL -1. The proposed method was validated with respect to accuracy, precision, limits of detection and quantification and robustness, etc.