白血病患者血清蛋白结合岩藻糖检测及其临床意义

检测28例白血病患者和28名正常人血清蛋白结合岩藻糖(PBF)值,发现急性白血病组血清PBF值明显高于正常对照组,慢粒,慢淋及慢粒急变者PBF值与正常无差异。完全缓解者血清PBF值下降并渐接近正常,复发时PBF值再次升高,提示血清PBF检测可作为观察白血病化疗效果和复发的指标。     

南极海茸多糖果冻的润肠通便功能研究

目的 制备南极海茸多糖果冻,研究其对便秘小鼠的润肠通便作用.方法 以南极海茸多糖为原料,制备1款酸甜可口的果冻.采用1.苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生.高效液相色谱法(HPLC)测定果冻中南极海茸多糖的含量.探索了南极海茸多糖果冻对便秘小鼠润肠通便作用:将昆明小鼠随机分为空白组、模型组、阳性对照组、果冻...     

HILIC-ELSD法测定岩藻聚糖硫酸酯中岩藻糖

目的 建立一种简便、高效、准确的测定岩藻聚糖硫酸酯中岩藻糖的方法。方法 采用超声处理(300 W 100%,20 ℃,20 min);三氟乙酸(4 mol/mL)水解(110 ℃、2 h);亲水作用色谱-蒸发光检测(HILIC-ELSD)法检测,Waters XBridge^TM Amide(150 mm×4.6 mm,3.5 μm)色谱柱,流动相为乙腈-水-氨水(90:10:0.2),体积流量1 mL/min,柱温60 ℃。结果 岩藻糖的线性范围为0.100 4~1.004 mg/mL(r=0.999 4),平均加样回收率95.22%(n=6,RSD=1.16%)。结论 该方法简便、快速、准确,为岩藻聚糖硫酸酯的定量分析和质量评价研究提供了依据。     

A monoclonal antibody to the galactan from Helix pomatia snails recognizes beta-(1,6)-linked D-galactose residues

Using the hybridoma technique, a series of four monoclonal antibodies to the galactan isolated from albumin glands of wine yard snails (Helix pomatia) could be generated. Characterization of the binding properties of one of these antibodies revealed a specificity for beta-(1,6)-glycosidically linked D-galactose residues. This could be demonstrated by reaction of the antibody with beta-(1,6)-D-galactans and by the D-galactose-inhibitable binding to group B streptococci of type II, which possess beta-(1,6)-linked D-galactose as immuno-determinant group.     

Challenge-induced plasma exudation and mucinous secretion in human airways

Secretion of mucins and exudation of plasma are distinct processes of importance to innate immunity and inflammatory disease. Yet, little is known about their relation in human airways. The objective of the present study was to use the human nasal airway to determine mucinous secretion and plasma exudation in response to common challenge agents and mediators. Ten healthy volunteers were subjected to nasal challenge-lavage procedures. Thus, the nasal mucosa was exposed to increasing doses of histamine (40 and 400 microg ml(-1)), methacholine (12.5 and 25 mg) and capsaicin (30 and 300 ng ml(-1)). Fucose was selected as a global marker of mucinous secretion and alpha(2)-macroglobulin as an index of exudation of bulk plasma. All challenge agents increased the mucosal output of fucose to about the same level (P<0.01-0.05). Once significant secretion had been induced the subsequently increased dose of the challenge agent, in the case of histamine and methacholine, failed to further increase the response. Only histamine increased the mucosal output of alpha(2)-macroglobulin (P<0.01). We conclude that prompt but potentially rapidly depleted mucinous secretion is common to different kinds of airway challenges, whereas inflammatory histamine-type mediators are required to produce plasma exudation. Along with the acknowledged secretion of mucins, a practically non-depletable, pluripotent mucosal output of plasma emerges as an important component of the innate immunity of human airways.     

Fucosylation of IgG heavy chains is increased in rheumatoid arthritis

Objectives: Glycosylation of IgG was suggested to be important in the etiology of rheumatoid diseases. Most studies addressed the amount of galactose, but recently we showed that fucose is highly increased in the juvenile chronic arthritis. The objective of this study was to determine fucosylation of IgG heavy chains in patients with rheumatoid arthritis (RA).

Design and methods: IgG was purified from sera of 29 RA patients and 17 matching controls using ammonium sulfate precipitation and ion exchange. Heavy chains were separated by denaturing polyacrylamide gel electrophoresis and their fucosylation analysed using fucose-specific UEA I lectin.

Results: Fucose was found to be approximately 40% increased in RA patients with very high statistical significance (p = 0.00095).

Conclusions: Fucose on IgG heavy chains is significantly increased in patients with rheumatoid arthritis.     

(1)H-MRS can detect aberrant glycosylation in tumour cells: a study of the HeLa cell line

Glycosylation is the most abundant and diverse form of post-translational modification of proteins. Two types of glycans exist in glycoproteins: N-glycans and O-glycans often coexisting in the same protein. O-glycosylation is frequently found on secreted or membrane-bound mucins whose overexpression and structure alterations are associated with many types of cancer. Mucins have several cancer-associated structures, including high levels of Lewis antigens characterized by the presence of terminal fucose. The present study deals with the identification of MR signals from N-acetylgalactosamine and from fucose in HeLa cells by detecting a low-field signal in one-dimensional (1D) spectra assigned to the NH of N-acetylgalactosamine and some cross peaks assigned to fucose in two-dimensional (2D) spectra. The increase of Golgi pH by treatment with ammonium chloride allowed the N-acetylgalactosamine signal assignment to be confirmed. Behaviour of MR peak during cell growth and comparison with studies from literature taken together made it possible to have more insight into the relationship between aberrantly processed mucin and the presence of non-processed N-acetylgalactosamine residues in HeLa cells. Fucose signals, tentatively ascribed to residues bound to galactose and to N-acetylglucosamine, are visible in both intact cell and perchloric acid spectra. Signals assigned to fucose bound to galactose are more evident in ammonium chloride-treated cells where structural changes of mucin-related Lewis antigens are expected as a result of the higher Golgi pH. A common origin for the N-acetylgalactosamine and fucose resonances attributing them to aberrantly processed mucin can be inferred from the present results.     

Stabilization of membrane-associated alpha-L-fucosidase by the human sperm equatorial segment

Previous reports from this laboratory documented the existence of two novel isoforms of α- l -fucosidase in human semen and showed that membrane-associated α- l -fucosidase is cryptically held within the acrosomal compartment and enriched within the sperm equatorial segment. The occurrence of these novel isoforms is provocative. Sperm proteins potentially involved in sperm–egg interactions must maintain their functional integrity as they travel through the female reproductive tract. The goal of this project was to investigate the stability of membrane-associated α- l -fucosidase in human sperm. Whole seminal plasma and Percoll^®purified sperm cell populations were incubated for 72 h at 37 °C, with 5% CO₂ or ambient air. At various times during prolonged incubation, sperm cells were permeabilized with 0.1% Triton^®X-100 and enzyme assays using the fluorogenic substrate 4-MU-fuc were performed to evaluate the stability of both the seminal plasma and membrane-associated α- l -fucosidase. Here, we report seminal plasma α- l -fucosidase activity rapidly decreased within 24 h. Conversely, α- l -fucosidase activity from Percoll^® purified sperm cell populations persisted up to 72 h. Data from these experiments support the notions that (i) membrane-associated α- l -fucosidase is stable for extended periods of time, consistent with a possible role in sperm–egg interaction and (ii) membrane domains and compartmentalization within the human sperm are key to preserving protein integrity.     

Six fucose‐α(1–2) sugars and α‐fucose assigned in the human brain using in vivo two‐dimensional MRS

A growing body of literature has indicated that fucose‐α(1–2)‐galactose sugars are implicated in the molecular mechanisms that underlie neuronal development, learning and memory in the human brain. An understanding of the in vivo roles played by these terminal fucose residues has been hampered by the lack of technology to non‐invasively monitor their levels in the human brain. We have implemented in vivo two‐dimensional MRS technology to examine the human brain in a 3‐T clinical MR scanner, and report that six fucose‐α(1–2)‐galactose residues and free α‐fucose are available for inspection. Fucose‐α(1–3)‐galactose residues cannot yet be assigned using this technology as they resonate under the water resonance. This new application offers an unprecedented insight into the molecular mechanisms by which fucosylated sugars contribute to neuronal processes and how they alter during development, ageing and disease. Copyright © 2014 John Wiley & Sons, Ltd.     

Changes in serum proteins and protein-bound carbohydrates in diabetes mellitus

Summary Studies of serum proteins and protein-bound carbohydrates were carried out on twenty-one diabetics without proteinuria and twenty controls. The diabetics had depression of serum total protein and albumin levels, and elevation of levels of all four types of protein-bound carbohydrate. The degree of elevation was greatest for fucose and least for sialic acid. When the diabetic group was divided into patients with and without evidence of retinopathy or neuropathy, the only significant difference found was an increase of alpha 2-globulin in diabetics with these sequelae. Alpha 2-globulin levels were found to be correlated with both fasting plasma glucose and duration of diabetes. Alpha 2-macroglobulin levels were elevated equally in diabetics with and without sequelae, and appeared related to atherosclerosis rather than to diabetes mellitus. Although disorders other than diabetes increase the magnitude of protein-bound carbohydrate elevation seen, their presence or absence has little influence on the fucose-dominated pattern of elevation found.Some of the material reported here was initially published in abstract form in Clinical Research 16, 129, 1968.