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Determination of sulfur anions by ion chromatography-postcolumn derivation and UV detection

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Chinese Chemical Letters 2009年第10期20卷 1241-1244页

作者： Mei Lan Chen ming li ye Xue ling Zeng Yun Chang Fan Zhu Yan College of Biology and Environmental Engineering Zhejiang Shuren University Hangzhou 310015 China Laboratory of Dionex Corporation Hangzhou 310028 China Department of Chemistry Xixi Campus Zhejiang University Hangzhou 310028 China

A novel method for determination of formaldehyde sulfoxylate, sulfite, thiocyanate, and thiosulfate in foodstuffs by ion chromatography separation with postcolumn derivation and UV detection has been developed. All species are separated at Dionex IonPac AG22A and AS22A with mobile phase of a mixture of 4.5 mmol/L sodium carbonate and 0.8 mmol/L sodium bicarbonate at a flow-rate of 1.0 mL/min. The postcolunm derivation solution was 0.24% iodine in 0.2% phosphate acid and the detection wavelength was set at 288 nm. The detection limits （LOD, signal-to-noise ratio of 3） of formaldehyde sulfoxylate, sulfite, thiocyanate, and thiosulfate were 0.004, 0.006, 0.006, and 0.007 mg/L, respectively. Within-day relative standard deviations （RSD, n = 10） of formaldehyde sulfoxylate, sulflte, thiocyanate, and thiosulfate were 3.24%, 3.76%, 2.68%, and 2.07%, respectively. The recoveries of the four anions were in the range of 67.2-116.5%.

关键词： Postcolumn derivation Ion chromatography Sulfur-containing inorganic compounds

Trace analysis of anions in organic matrices by ion chromatography coupled with a novel reversed-phase column for on-line sample pretreatment

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Chinese Chemical Letters 2011年第4期22卷 461-464页

作者： Ying Ying Zhong Wen Fang Zhou Xue ling Zeng ming li ye Yan Zhu Department of Chemistry Zhejiang UniversityHangzhou 310028China Ningbo Entry-Exit Inspection and Quarantine Bureau Ningbo 315012China

An ion chromatography（IC） system coupled with on-line column-switching technique was used to determine anions ofμg/g levels in organic chemicals of analytical reagent grade.A novel polystyrene-divinylbenzene-carbon nanotube（PS-DVB-CNT） stationary phase was utilized for matrix elimination.A calibration study was conducted by preparing and analyzing eight concentrations（between 10 and 5000μg/L） of eight standards in deionized *** linearity was between 0.9978 and *** the detection limits ranged from 1.54μg/L to 10.02μg/L.A spiking study was performed on two representative organic *** recoveries were between 84.3%and 119.6%.

关键词： Ion chromatography Column switching Trace anions Organic matrix Polymer stationary phase

Determination of levels of adenosine phosphates in blood by ion chromatography

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Chinese Chemical Letters 2011年第12期22卷 1485-1488页

作者： Pei Jin Xie ming li ye Zhong Yang Hu Guang Wen Pan Yan Zhu Jia Jie Zhang Department of Chemistry Zhejiang UniversityHangzhou 310028China Shanghai Lab Dionex China Co.Ltd.Shanghai 201203China

A new method was developed for simultaneous determination of levels of AMP,ADP and ATP in blood by anion-exchange *** three adenosine phosphates were separated by Dionex IonPac AG18（50 mm×4 mm） guard column and IonPac AS 18（250 mm×4 mm） analytical column using a gradient method and detected with a suppressed conductivity detector. The detection limits（S/N=3） of AMP,ADP and ATP were 38,47,108 ng/L,*** relative standard deviations of retention time,peak area and peak height were all less than 1.87%and a good linear relationship was *** method was applied to analyze human blood samples.

关键词： Adenosine phosphate Ion chromatography Blood

Estimating health damage cost from secondary sulfate particles—a case study of Hunan Province,China

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Journal of Environmental Sciences 2003年第5期15卷 611-617页

作者： HAO Ji ming, li Ji, ye Xue mei, ZHU Tian le (Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China. ) Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

China's coal dominated energy pattern has resulted in large amount of SO 2 emissions. Estimate of the sulfur related health damage cost is necessary to help perform systematic cost benefit analysis and set national energy and emissions control priorities. Current researches were confined to gaseous SO 2 in urban areas; however, secondary sulfate (SO 2- 4) particles can exert serious impact in a wider region. Based on the concept of “intake fraction', CALPUFF long range dispersion model and 180 sample emission sources, multiple regression equation was obtained with good correlation( r =0 85), which illustrates that populations were key parameters to determine intake fraction but source characteristics were insignificant. Based on the formula and the population distribution data, county level intake fractions were mapped for Hunan Province(range: 1 1×10 -6 -3 2×10 -6 ) of China. A combination of county level SO 2 emissions with the intake fractions yields a total 1 98 tons of sulfate(SO 2- 4) inhalation, and resulting total health damage cost to be 0 76(willingness to pay approach, WTP) or 0 16(human capital approach, HC) billion USD in 1997, about 2.1% or 0 45% of GDP in Hunan in 1997. Average health damage cost per ton of SO 2 emission is 930(WTP) or 200 USD(HC). The results demonstrated that more stringent regulation should be forced.

关键词： intake fraction health impact Hunan Province sulfate regression analysis

Transplantation of microencapsulated umbilical-cord-blood-derived hepatic-like cells for treatment of hepatic failure

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World Journal of Gastroenterology 2011年第7期17卷 938-945页

作者： Fang-Ting Zhang Hui-Juan Wan ming-Hua li Jing ye Mei-Jun Yin Chun-Qiao Huang Jie Yu Central Laboratory Peking University Shenzhen Hospital Shenzhen 518036 China

AIM: To investigate intraperitoneal transplantation of microencapsulated hepatic-like cells from human umbilical cord blood for treatment of hepatic failure in rats. METHODS: CD34+ cells in umbilical cord blood cells were isolated by magnetic cell sorting. In the in vitro experiment, sorted CD34+ cells were amplified and induced into hepatic-like cells by culturing with a combination of fibroblast growth factor 4 and hepatocyte growth factor. Cultures without growth factor addition served as controls. mRNA and protein levels for hepatic-like cells were analyzed by reverse transcription-polymerase chain reaction, immunohistochemistry and immunofluorescence. In the in vivo experiment, the hepatic-like cells were encapsulated and transplanted into the abdominal cavity of acute hepatic failure (AHF) rats at 48 h after D-galactosamine induction of acute hepatic failure. Transplantation with PBS and unencapsulated hepatic-like cells served as controls. The mortality rate, hepatic pathological changes and serum biochemical indexes were determined. The morphology and structure of microcapsules in the greater omentum were observed. RESULTS: Human albumin, alpha-fetoprotein and GATA-4 mRNA and albumin protein positive cells were found among cultured cells after 16 d. Albumin level in culture medium was significantly increased after culturing with growth factors in comparison with culturing without growth factor addition (P lity rate of the encapsulated hepatic-like cell-transplanted group was significantly lower (P lirubin in the encapsulated group were significantly improvement compared with the PBS control group (P < 0.01). Pathological staining further supported these findings. At 1-2 wk post-transplantation, free microcapsules with a round clear structure and a smooth surface were observed in peritoneal lavage fl

关键词： Microencapsulation Hepatic-like cells Umbilical cord blood cells CD34 antigen Alginate Acute hepatic failure

Determination of common anions in oxalate by ion chromatography coupled with UV photolysis pretreatment

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Chinese Chemical Letters 2012年第11期23卷 1263-1266页

作者： Sheng lin Cao ming li ye Wei De Lv Guang Wen Pan Ting Ting Zhang Zhong Yang Hu li Na liang Yan Zhu Department of Chemistry Zhejiang UniversityHangzhou 310028China Shanghai Lab Thermo Fisher Scientific Inc.Shanghai 201203China Hangzhou Vocational and Technical Institute Hangzhou 310018China

A new and simple method was developed to determine anions in oxalate of analytical reagent grade. After UV photolysis with optimal 1% H2O2 in 10,000 mg/L oxalate in the fabricated photoreactor, sample was directly injected into IC system. Satisfactory linearity, detections limits, good repeatability and spiked recovery were obtained. The method was successfully applied to determine anions in two commercial oxalate samples.

关键词： Ion chromatography UV photolysis Oxalate Common anions

Profiling the dynamics of abscisic acid and ABA-glucose ester after using the glucosyltransferase UGT71C5 to mediate abscisic acid homeostasis in Arabidopsis thaliana by HPLC–ESI-MS/MS

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Journal of Pharmaceutical Analysis 2014年第3期4卷 190-196页

作者： Dong-Mei Xiong Zhen liu Han Chen Jin-Tao Xue Yi Yang Cong Chen li-ming ye West China School of Pharmacy Sichuan University College of life Science Sichuan University

The HPLC-MS/MS method was developed to profile the dynamics of abscisic acid （ABA） and ABA-glucose ester （ABA-GE） after cloning glycosyltransferase enzyme family gene AtUGT71C5 into Arabidopsis thaliana. By constructing over-expression lines （OE） and down-expression lines （DN）, we acquired mutant strains to analyze the function of AtUGT71C5. The multiple-reaction monitoring （MRM） was used for quantitative determination in negative mode. The transition was m/z 263.1→153.0 for ABA （[M-H]^＋）, m/z 425.1→263.0 for ABA-GE （[M-H]^＋）, and m/z 321.0-152.0 for chloramphenicol. The linear range was 0.8684-217.1 ng/mL for ABA and 0.3920-196.0 ng/mL for ABA-GE. The accuracy was 88.0-109.0% for ABA and 86.6-113.0% for ABA-GE; the inter-day and intra-day precisions were less than 5.4%for ABA and 8.9%for ABA-GE, respectively. This method is simple and sensitive enough for determination of ABA and ABA-GE in A. thaliana leaves. All the evidence confirmed the speculation that AtUGT71C5 can mediate abscisic acid homeostasis.

关键词： HPLC-MS/MSABA ABA-GE AtUGT71C5

Release test of alliin/alliinase double-layer tablet by HPLC-Allicin determination

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Journal of Pharmaceutical Analysis 2013年第3期3卷 187-192页

作者： Yan liang Jing-Jing Zhang Qi-Bing Zhang Zhong-Xia Wang Zong-Ning Yin Xin-Xia li Jian Chen li-ming ye West China School of Pharmacy Sichuan University Xinjiang Medical University

A simple, precise and accurate method was developed and validated for the determination of allicin release from alliin/alliinase double-layer tablets. According to Appendix XC Ⅱ of Chinese Pharmacopoeia 2010 edition Volume II, a small glass-method was adopted at the rotational speed of 100 r/min using 100 mL phosphate buffer （pH 6.8） as release medium. The release amount was determined by HPLC with a C18 column （250 mm × 4.6 mm, 5 μm） using the mobile phase consisting of methanol -0.4% carboxylic acid （65：35） at a flow rate of 1 mL/min and UV detection at 242 nm. The current method demonstrates good linearity over the range 4.052- 405.2 μg/mL （r2=0.9999） with an average recovery of 105.5%（RSD= 1.25%）. The accumulative release of alliin/alliinase double-layer tablets had good homogeneity for withinand betweenbatches. The method established is simple, accurate and repeatable for the determination of allicin release from alliin/alliinase double-layer tablets.

关键词： Alliin/alliinase Double-layer tablet Allicin Release test HPLC

Cobra phospholipase A2 protect cerebellar granule neurons from apoptosis with mechanism independent of enzymatic activity

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Journal of life Sciences 2008年第1期2卷 6-11页

作者： li ming-tao ye Yan-ying HUANG Shou-jian Department of Pharmacology Zhongshan Medical College Sun Yat-sen University Guangzhou 510089 China

A fraction of cobra （Naja naja atra） venom has been discovered to have protective effect on rat cultural cerebellar granule neurons （CGNs） from apoptosis induced by removing serum and reducing the extracellular potassium concentration from 25 to 5 mM. This component has been purified and identified as secreted phospholipase A2 （cobra sPLA2）. In order to study the relationship between the protection on CGNs and enzymatic activity of phospholipase A2, CGNs stained by Hoechst 33258 were quantified to determine survival rate under the fluorescence microscopy; the protective potencies on apoptosis of cultural CGNs were compared among cobra sPLA2, the cobra sPLA2 modified in carboxylate groups with water soluble carbodiimide and semicarbazide, and the heated cobra sPLA2 at 80℃ for 30 rain. The results showed that the CGN survival rate was unaffected significantly both in modified cobra sPLAz whose enzymatic activity of PLA2 had decreased by 80%, and in cobra sPLA2 adding 7, 7-Dimethyleicosadienoic acid, an inhibitor of sPLA2 at concentration of 10-fold IC50; contrary, the neuronal survival rate fell about 60% in heated cobra sPLA2, although its PLA2 activity only decreased by 10%. The protection on CGNs were also found in some of sPLA2s derived from venoms of bee, Naja naja mossambica, Crotalus atroxalso and Vipera Ammodytes Ammodytes but could not be found in other sPLA2s from bovine pancreas and Streptomyces violaceoruber. Above results suggest that the protection on CGNs of cobra sPLA2 is independent of its enzymatic activity.

关键词： secreted phospholipase A2 (sPLA2) CerebellarGranule Neurons (CGNs) apoptosis enzymatic activity