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Chinese Chemical Letters 2019年第3期30卷 676-680页

作者： Xiaoman Zhou Shang Yang Ganglong Yang Zengqi Tan Feng Guan The Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of Education School of Biotechnology Jiangnan University Joint International Research Laboratory of Glycobiology and Medicinal Chemistry College of Life Science Northwest University

Sialylation is one of important glycosylation in human beings and plays an important role in cancer development. α2,3-Linked and α2,6-linked sialic acids are normally observed on the end of N-glycans and have different functions. Derivatization on sialic acid was designed to detect the different linkages by MALDI-TOF MS. In this study, a two-step derivatization by dimethylamine and ammonium hydroxide was improved to modify the sialic acid and made it easier to detect the different linkages of sialic acids on MALDI-TOF MS. Using this derivatization method, specific sialic acids linkages on N-glycans of protein samples such as fetuin and lactoferrin were detected. For complex cell samples, increased a2,3-linked and a2,6-linked sialic acids on bi-antennary and tri-antennary N-glycans were observed in A549 cells induced by hypoxia environment. Taken together, our two-step derivatization of sialic acids offers a simple and accurate way to detect specific linkages on N-glycans with MALDI-TOF mass spectrometer.

关键词： sialic acid N-Glycans Derivatization MALDI-TOF Hypoxia

Serum Contents of sialic Acids in Mice Bearing Different Tumors

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Chinese Science Bulletin 1994年第14期39卷 1220-1223页

作者：卢大用梁罡张明坚胥彬 Shanghai University of Science and Technology Shanghai 201800 PRC Shanghai Institute of Materia Medica Academia SinicaShzngai 20031PRC

sialic acids are the derivatives of aminosugar whose parental structures are formed by nine carbons. Recently, the sialic acids have been found to be related to cell malignancy, i.e. the increasing amount of sialic acids on cell membrane, the types of sialic acids, sialyltransferase activity, and sialyltransferase inhibitor can inhibit the tumor metastases. This work tries to explore the tumor-sialic acid relation and the influences of antineoplastic drugs on free sialic acids in mice sera by means of HPLC.

关键词： sialic acids HPLC antineoplastic drugs neoplasm metastases carcinogeneses.

Quantitative analysis of sialic acids in Chinese conventional foods by HPLC-FLD

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Open Journal of Preventive Medicine 2014年第2期4卷 57-63页

作者： Hongwei Li Xingdan Fan Department of Preventive Medicine School of Public Health Xiamen University Xiamen China

Background: sialic acids are a family of ninecarbon sugar compounds with carboxylic acyl derivatives. It exists in bacteria, fish, mammals and other living organisms, participates in and regulates many important life events, such as cell recognition, membrane flow, endocytosis and so on. sialic acid is usually located in the outermost layer of the sugar part of the cell membrane and the key positions of secreted glycoconjugates (glycolipids, glycoprotein and lipopolysaccharide). sialic acid (Sia) is an important material foundation for variety of the structure and founction of glycoconjugates. Sia has been known as nearly 50 members, including N-acetylneuraminic acid (Neu5Ac), N-glycoulylneuraminic acid (Neu5Gc) and deaminoneuraminic acid (KDN) as its core monomer. The rest of the sialic acids are derived from these three monomers. The contents of Sia in Chinese food products are unknown. Objective: To determine the contents of Sia in raw and cooked red meat, seafood, poultry and so on. Design: The following food products were purchased from a Chinese supermarket: pork, beef, lamb, salmon, cod, tuna, cow milk, cheese, butter, duck, chicken and chicken eggs. Human milk was collected from Xiamen Maternity and Child Health Care Hospital (Xiamen, China). All tissues were homogenized and hydrolyzed with 0.05 M, 0.1 M and 0.2 M TFA for 150 min at 80°C in dark, respectively. The concentrations of Neu5Ac, Neu5Gc and KDN were determined by using HPLC with fluorescence detector. Results: The contents of total Sia (μg/g tissue or μg/mL liquid sample) in Chinese raw meat were highest in lamb (269.60), followed by pork (254.88), duck (200.63), chicken (162.86) and beef (88.03). The percentages of Neu5Gc were 36.08%, 26.48%, 0%, 0% and 28.40%, respectively. Cod contained higher levels of Sia (171.63) than salmon (104.43) and tuna (77.98). Only Neu5Ac was 50 found in detected aquatic product. Egg yolk contained the highest level of Sia (682.04), and a higher level of Sia (390.67)

关键词： Quantitative Analysis sialic Acids HPLC-FLD

Bitter Melon (Momordica Charantia) Reduces Serum sialic Acid in Type2 Diabetics: Evidence to Delay the Process of Atherosclerosis

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Chinese Medicine 2011年第4期2卷 125-129页

作者： Inayat Ur Rahman Mohammad Bashir Mohammad Salman Mohammad Idrees Mohammad Iqbal Khan 不详

More than 1000 herbal products have been used by diverse cultures of the world to treat hyperglycemia and among them bitter melon (Momordica charantia) is one of the most popular herbal resource. The beneficial effects of bitter melon is not limited to hypoglycaemia only, but it also ameliorates diet induced obesity, insulin resistance and exhibit cardioprotective effects. The present study attempts to investigate the effect of bitter melon fruit juice on a newly investigated risk factor, sialic acid in type2 diabetics. A total of 40 type2 diabetic patients, divided into group A (n = 20) and group B (n = 20) were investigated during the present study. The patients of group A were following bitter melon fruit juice treatment along with diet control, whereas the patients of group B were on diet control only. Serum sialic acid (SSA) decreased in group A from 66.20 ± 2.30 mg/dl to 63.50 ± 2.10 mg/dl (<0.11) but, increased in group B from 66.50 ± 1.70 mg/dl to 68.20 ± 2.50 mg/dl (<0.12), compared to baseline. Post-treatment between group comparison revealed a significant difference (<0.05). The beneficial effects on fasting plasma glucose (FPG) and glycohemoglobin (HbA1-c) were also greater in group A compared to group B as was the case with blood lipids, weight and blood pressure. The study provides another mechanism for the cardioprotective effect of bitter melon and further strengthens its value in the management of type2 diabetes.

关键词： sialic Acid Type2 Diabetes Mellitus Bitter Melon Cardiovascular Disease

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液相色谱-质谱法对奶粉中唾液酸含量的测定

分析测试学报 2008年第S1期27卷 193-194页

作者：栗晖金一宝刘红霞于治国高春梅蒋宇扬清华大学深圳研究生院广东省化学生物学重点实验室广东深圳518055 沈阳药科大学辽宁沈阳110016 清华大学医学院北京100084

A simple and sensitive ion-paring HPLC-MS/MS method with negative ion mode has been developed and validated for the quantification of SA in *** separation was performed on C18 column with a mobile phase consisting of 4 mmol/L tetrabutylammonium hydroxide-methanol at a flow rate of 0.2 mL/min under the gradient *** retention time of SA was 6.1 ***-quadrupole MS/MS detection was operated in negative mode by monitoring the transition of m/z 308.1>87.1 for *** results indicated that the lower limit of quantification was 0.060 mg/L and the assay showed a linear range of 0.1-100 mg/L and gave a correlation coefficient(r) of *** relative standard deviations were less than 10% at all tested concentration *** method has been successfully applied to the analysis of SA in milk,milk powder and breast milk.

关键词： sialic acid ion-pair HPLC-MS/MS

Protective effect of Cardiospermum halicacabum leaf extract on glycoprotein components on STZ-induced hyperglycemic rats

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Asian Pacific Journal of Tropical Medicine 2012年第12期5卷 939-944页

作者： Chinnadurai Veeramani Khalid S Al-Numair Mohammed A Alsaif Govindasamy Chandramohan Nouf S Al-Numair Kodukkur Viswanathan Pugalendi Department of Community Health Sciences College of Applied Medical SciencesKing Saud University Department of Structural and Molecular Biology University College LondonDarwin BuildingCower StreetLondonWCIE 6BT Department of Biochemistry and Biotechnology Annamalai University

Objective:To investigate the protective role of Cardiospermum halicacabum(***) leaf extract on glycoprotein metabolism in streptozotocin(STZ)-induced diabetic ***: Diabetes was induced in male albino Wistar rats by intraperitonial administration of *** *** leaf extract(CHE) was administered orally to normal and STZ-diabetic rats for 45 *** effects of *** leaf extract(CHE) on plasma and tissue glycoproteins (hexose,hexosamine,fucose and sialic acid) were ***:The levels of plasma and tissues glycoproteins containing hexose,hexosamine and fucose were significantly increased in STZ-induced diabetic *** addition,the level of sialic acid significantly increased in plasma and liver while decreased in kidney of STZ-induced diabetic *** administration of CHE to diabetic rats,the metabolic alteration of glycoprotein reverted towards normal levels. Conclusions:The present study indicates that the CHE possesses a protective effect on abnormal glycoprotein metabolism in addition to its antihyperglycemic activity.

关键词： Streptozotocin Cardiospermum halicacabum leaf extract Hexose Hexosamine Fucose sialic acid

Tissue and host tropism of influenza viruses:Importance of quantitative analysis

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Science China(Life Sciences) 2009年第12期52卷 1101-1110页

作者： ZHANG Hong1,2 1 Z-BioMed, Inc., Rockville, MD 20855, USA 2 Department of Respiratory Medicine, Affiliated Hospital of Zunyi Medical College, Zunyi 563003, China Z-BioMed Inc. Rockville USA Department of Respiratory Medicine Affiliated Hospital of Zunyi Medical College Zunyi China

It is generally accepted that human influenza viruses preferentially bind to cell-surface glycoproteins/ glycolipids containing sialic acids in α2,6-linkage; while avian and equine influenza viruses preferentially bind to those containing sialic acids in α2,3-linkage. Even though this generalized view is accurate for H3 subtype isolates, it may not be accurate and absolute for all subtypes of influenza A viruses and, therefore, needs to be reevaluated carefully and realistically. Some of the studies published in major scientific journals on the subject of tissue tropism of influenza viruses are inconsistent and caused confusion in the scientific community. One of the reasons for the inconsistency is that most studies were quantitative descriptions of sialic acid receptor distributions based on lectin or influenza virus immunohistochemistry results with limited numbers of stained cells. In addition, recent studies indicate that α2,3- and α2,6-linked sialic acids are not the sole receptors determining tissue and host tropism of influenza viruses. In fact, determinants for tissue and host tropism of human, avian and animal influenza viruses are more complex than what has been generally accepted. Other factors, such as glycan topology, concentration of invading viruses, local density of receptors, lipid raft microdomains, coreceptors or sialic acid-independent receptors, may also be important. To more efficiently control the global spread of pandemic influenza such as the current circulating influenza A H1N1, it is crucial to clarify the determinants for tissue and host tropism of influenza viruses through quantitative analysis of experimental results. In this review, I will comment on some conflicting issues related to tissue and host tropism of influenza viruses, discuss the importance of quantitative analysis of lectin and influenza virus immunohistochemistry results and point out directions for future studies in this area, which should lead to a better understanding

关键词： tissue and host tropism influenza viruses sialic acid receptors quantitative analysis

Erythrocyte invasions and receptor heterogeneity in field isolates of Nanay river basin Iquitos

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Asian Pacific Journal of Tropical Medicine 2012年第8期5卷 589-593页

作者： Kuppusamy Chenniappan Sarah H Johns Laboratorio de Investigacion deproductos Naturales Antiparasitarios de la Amazonia UNAPPampa chicaIquitosPeru 065

Objective:To determine whether the requirements for sialic acid varies and whether several types of silaic acid independent receptors utilized for invasion mechanisms of fresh filed isolates collected around Nanay river basin,***:The field isolates were cultured as described previously by Jensen and Trager and MR4 protocol with little *** erythrocytes preparation and subsequent enzyme treatment was done as described previously by *** little *** assay was performed as described previously by Sharma et al with little ***:The Nanay river basin isolates showed five types of invasion mechanisms or types of receptors-ligand *** we observed that an equal numbers of neuraminidase sensitive and resistant invasion receptor-ligand interaction profiles as the most common receptor-ligand invasion *** resistance trypsin sensitive chymotrypsin sensitive(NM_RT_SCT_S) invasion of receptor-ligand interaction profile was found in seven isolates,Five field isolates and one reference strain showed neuraminidase sensitive, trypsin sensitive and chymotrypsin resistant(NM_RT_SCT_R) invasion of receptor-ligand interactions, six isolates including one reference strains dd2 showed neuraminidase sensitive,trypsin and chymotrypsin resistance(NM_ST_RCT_R) indicating its dependence on sialic acids and independence of trypsin and chymotrypsin sensitive *** isolates showed neuraminidase sensitive, trypsin sensitive and chymotrypsin sensitive(NM_ST_SCT_S) invasion of receptor-ligand interactions, seven isolates were neuraminidase resistant,trypsin sensitive and chymotrypsin resistance (NM_RT_SCT_R) invasion of receptor-ligand interactions,indicating its dependence on trypsin sensitive ***:The Nanay river basin isolates showed five types of invasion mechanisms or types of receptors-ligand interactions.A full understanding of theses invasion mechanisms may allow the developm

关键词： Nanay river basin Invasion sialic acid Plasmodium falciparum Malaria

Combined measurement of serum tumor markers in patients with hepatocellular carcinoma

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World Journal of Gastroenterology 1998年第2期4卷 89-90页

ＣｏｍｂｉｎｅｄｍｅａｓｕｒｅｍｅｎｔｏｆｓｅｒｕｍｔｕｍｏｒｍａｒｋｅｒｓｉｎｐａｔｉｅｎｔｓｗｉｔｈｈｅｐａｔｏｃｅｌｕｌａｒｃａｒｃｉｎｏｍａＣＡＩＷｅｎＸｉｕ，ＺＨＥＮＧＨｕｉ，ＳＨＥＮＧＪｉａｎａｎｄＹ... 详细信息

ＣｏｍｂｉｎｅｄｍｅａｓｕｒｅｍｅｎｔｏｆｓｅｒｕｍｔｕｍｏｒｍａｒｋｅｒｓｉｎｐａｔｉｅｎｔｓｗｉｔｈｈｅｐａｔｏｃｅｌｕｌａｒｃａｒｃｉｎｏｍａＣＡＩＷｅｎＸｉｕ，ＺＨＥＮＧＨｕｉ，ＳＨＥＮＧＪｉａｎａｎｄＹＥＱｉｎｇＬｉｎＳｕｂｊｅｃｔｈ...

关键词： liver neoplasms/diagnosis carcinoma, hepatocellular/diagnosis tumor markers, biological/blood alphafetoproteins/blood sialic acid/blood fucosidase/blood enzyme linked immunosorbent assay spectrophotometry

Substrate specificity of avian influenza H5N1 neuraminidase

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World Journal of Virology 2014年第4期3卷 30-36页

作者： Naruthai Onsirisakul Shin-ichi Nakakita Chompunuch Boonarkart Alita Kongchanagul Ornpreya Suptawiwat Pilaipan Puthavathana Krisada Chaichuen Kanokwan Kittiniyom Yasuo Suzuki Prasert Auewarakul Department of Clinical Microbiology and Applied Technology Faculty of Medical TechnologyMahidol UniversityBangkok 73170Thailand Department of Microbiology Faculty of Medicine Siriraj HospitalMahidol UniveristyBangkok 10700Thailand Division of Functional Glycomics Life Sciences Research CenterKagawa UniversityTakamatsu 761-0793Japan Institute of Molecular Biosciences Mahidol UniversityNakhon Pathom 73170Thailand Faculty of Veterinary Science Mahidol UniversityNakorn Pathom 73170Thailand College of Life and Health Sciences Chubu UniversityKasugai 487-8501Japan

AIM: To characterise neuraminidase(NA) substrate specificity of avian influenza H5N1 strains from humans and birds comparing to seasonal influenza ***: Avian influenza H5N1 strains from humans and birds were recruited for characterising their NA substrate specificity by using a modified commercial fluorescence Amplex Red assay. This method can identify the preference of α2,6-linked sialic acid or α2,3-linked sialic acid. Moreover, to avoid the bias of input virus, reverse genetic virus using NA gene from human isolated H5N1 were generated and used to compare with the seasonal influenza virus. Lastly, the substrate specificity profile was further confirmed by high-performance liquid chromatography(HPLC) analysis of the enzymatic product. RESULTS: The H5N1 NA showed higher activity on α2,3-linked sialic acid than α2,6-linked(P sialic acid than that of the H3N2 virus, whereas the activities on α2,6-linkage were comparable. Interestingly, NA from an H5N1 human isolate that was previously shown to have heamagglutinin(HA) with dual specificity showed reduced activity on α2,3-linkage. To confirm the substrate specificity profile, HPLC analytic of enzymatic product was performed. Similar to Amplex red assay, H5N1 virus showed abundant preference on α2,3-linked sialic ***: H5N1 virus maintains the avian specific NA and NA changes may be needed to accompany changes in HA receptor preference for the viral adaptation to humans.

关键词： H5N1 avian influenza virus Neuraminidase sialic acid Adaptation Substrate preference