糖类的高效毛细管电泳分析

目的：探讨糖类物质的检测方法。方法：通过文献，结合HPCE方法的特点进行糖类物质的测定。结果：通过柱前衍生、不经衍生的直接和间接紫外检测、荧光检测和电极脉冲安培检测均可对糖类物质进行分析。结论：HPCE技术对糖类物质分析提供了有效的保证。     

柱前衍生化法测定五维牛磺酸口服液中牛磺酸的含量

五维牛磺酸口服液作为维生素补充药物,在临床已应用多年.现行的国家标准未制定活性成份牛磺酸的含量测定方法.牛磺酸结构中不含共轭体系,无法通过普通的UV检测器直接测定.此类物质可通过柱前衍生化引入发色基团后进行检测.我们采用柱前衍生化法,以2,4-二硝基氟苯作衍生化试剂测定牛磺酸的含量.     

衍生化HPLC/MS法测定有机羧酸物质的研究进展

利用高效液相色谱-质谱联用 (HPLC/MS) 法对体液中微量的羧酸化合物进行定量检测仍然是一个难题。近年的研究显示采用衍生化质谱增敏法成为解决这一问题的重要方法。本文综述了近年来应用此类方法测定微量羧酸物质的研究,并对研究中所采用的衍生化试剂和化学反应进行了总结。     

AQC柱前衍生法在氨基酸分析测定中的应用

氨基酸分析是生物医药研究工作中十分重要的技术之一,大多数氨基酸和胺类化合物无吸收和荧光发射特征,进行化学衍生化是提高其分析检测灵敏度和特异性的有效手段,其中,AQC柱前衍生法是近几年广为接受的方法。本文对AQC柱前衍生法在氨基酸分析测定中的原理、影响因素及其应用情况进行综述。     

红花注射液中糖类成分的分析测定研究

目的 测定红花注射液中的糖类成分含量.方法 用苯酚硫酸法对红花注射液中的总糖、单糖和寡糖含量进行了测定,用PMP衍生化法对单糖进行了鉴别研究.结果 红花注射液中的总糖含量约占总固体量的50%,其中单糖和寡糖在总糖中占比较高,单糖主要是葡萄糖、半乳糖和木糖,多糖在注射液中的含量较少.结论 苯酚硫酸法操作简单,条件易控制,重现性较好,可以用于红花注射液中糖类成分的检测分析.     

糖类物质的色谱分析

综述了糖类化合物的色谱分离和检测的方法，包括气相色谱、高效液相色谱和毛细管电泳，主要对糖类化合物衍生方法进行了较为详细的介绍。     

氨基酸柱前衍生化法在动物药质量控制中的应用简

查阅了目前应用于动物药中氨基酸类成分检测的几种常用柱前衍生化方法的研究相关文献,对其应用情况、优缺点以及衍生化条件、检测条件进行归纳总结,并就目前存在的问题及今后的研究方向进行探讨。     

柱前手性衍生化-反相高效液相色谱法拆分布洛芬对映异构体

目的：建立一种柱前手性衍生化-反相高效液相色谱紫外法检测布洛芬的异构体。方法：以N′N-羰基二咪唑（CDI）作为活化剂活化布洛芬的羧基基团,再以（R）-（+）-1-（1-萘基）乙胺（R-NEA）作为手性衍生化试剂进行反应。选用Kromasil C18色谱柱,流速1.0 mL·min-1,柱温30 ℃,以乙腈-0.05%磷酸（68∶32）为流动相,检测波长225 nm。结果：布洛芬的非对映异构体色谱峰的保留时间分别为25.6 min和27.9 min。结论：本方法操作简单,条件温和,衍生化产物稳定,且衍生化试剂价格便宜,更准确地实现了对布洛芬对映异构体的分离检测。     

基于柱前衍生-高效液相色谱-串联质谱联用技术的骨肽注射液中10种生物胺定量测定方法及其稳定性研究

目的:采用柱前衍生化-高效液相色谱-串联质谱联用技术建立骨肽注射液中生物胺类物质定量测定方法,并通过影响因素试验和加速试验考察其生物胺类物质的稳定性。方法:采用丹磺酰氯衍生化法对样品进行前处理,经ZORBAX SB-C₁₈色谱柱梯度洗脱分离,电喷雾离子源正离子模式下多反应监测,对骨肽注射液中10种生物胺进行定量测定,并于高温条件、强光照条件和加速试验条件下考察生物胺类物质的稳定性。结果:方法学考察结果显示10种生物胺线性关系良好,相关系数均大于0.990,方法检测限为0.01～0.10 ng·mL^-1,定量限为0.05～0.30 ng·mL^-1,准确性、重复性和耐用性较好。稳定性研究结果显示不同条件下骨肽注射液中生物胺类物质变化存在差异,高温条件下腐胺增多,精胺和亚精胺减少,强光照条件及加速试验条件中生物胺类物质含量均存在变化。结论:方法学验证表明该方法可用于同时测定骨肽注射液中10种生物胺,为骨肽及其它药品质量标准中生物胺类物质检测方法的建立和完善提供了参考,同时生物胺类物质稳定性研究结果表明高温及强光条件可对其稳定性...     

糖类物质受体的研究进展

关于糖类物质的研究近年来越来越引起人们的极大兴趣。糖类物质具有广泛的生物学活性,其免疫调节作用是实现其生物学活性的重要机制之一。糖类物质生物学活性的发挥,主要是通过与细胞上不同的糖类物质受体相互作用,再经一系列信号转导的过程而实现的。该文综述了糖类物质的受体以及糖与受体蛋白的相互作用特点。     

Carbohydrates in therapeutics

Awareness of the importance of carbohydrates in living systems and medicine is growing due to the increasing understanding of their biological and pharmacological relevance. Carbohydrates are ubiquitous and perform a wide array of biological roles. Carbohydrate-based or -modified therapeutics are used extensively in cardiovascular and hematological treatments ranging from inflammatory diseases and anti-thrombotic treatments to wound healing. Heparin is a well-known and widely used example of a carbohydrate-based drug but will not be discussed as it has been extensively reviewed. We will detail carbohydrate-based and -modified therapeutics, both those that are currently marketed or in various stages of clinical trials and those that are potential therapeutics based on promising preclinical investigations. Carbohydrate-based therapeutics include polysaccharide and oligosaccharide anti-inflammatory, anti-coagulant and anti-thrombotic agents from natural and synthetic sources, some as an alternative to heparin and others which were designed based on known structure-functional relationships. Some of these compounds have multiple biological effects, showing anti-adhesive, anti-HIV and anti-arthrithic activities. Small molecules, derivatives or mimetics of complement inhibitors, are detailed for use in limiting ischemia/ reperfusion injuries. Monosaccharides, both natural and synthetic, have been investigated for their in vivo anti-inflammatory and cardioprotective properties. Modification by glycosylation of natural products, or glycosylation-mimicking modification, has a significant effect on the parent molecule including increased plasma half-life and refining or increasing desired functions. It is hoped that this review will highlight the vast therapeutic potential of these natural bioactive molecules.     

Carbohydrates and dietary fiber

The most widely spread eating habit is characterized by a reduced intake of dietary fiber, an increased intake of simple sugars, a high intake of refined grain products, an altered fat composition of the diet, and a dietary pattern characterized by a high glycemic load, an increased body weight and reduced physical activity. In this chapter the effects of this eating pattern on disease risk will be outlined. There are no epidemiological studies showing that the increase of glucose, fructose or sucrose intake is directly and independently associated with an increased risk of atherosclerosis or coronary heart disease (CHD). On the other hand a large number of studies has reported a reduction of fatal and non-fatal CHD events as a function of the intake of complex carbohydrates--respectively 'dietary fiber' or selected fiber-rich food (e.g., whole grain cereals). It seems that eating too much 'fast' carbohydrate [i.e., carbohydrates with a high glycemic index (GI)] may have deleterious long-term consequences. Indeed the last decades have shown that a low fat (and consecutively high carbohydrate) diet alone is not the best strategy to combat modern diseases including atherosclerosis. Quantity and quality issues in carbohydrate nutrient content are as important as they are for fat. Multiple lines of evidence suggest that for cardiovascular disease prevention a high sugar intake should be avoided. There is growing evidence of the high impact of dietary fiber and foods with a low GI on single risk factors (e.g., lipid pattern, diabetes, inflammation, endothelial function etc.) as well as also the development of the endpoints of atherosclerosis especially CHD.     

Serotonin,Carbohydrates, and Atypical Depression

At least three categories of atypical depression have been described. The hysteroid dysphoria is characterized by repeated episodes of depressed mood in response to feeling rejected, and a craving for sweets and chocolate. Two other issues are characterized by a cyclical occurrence of changes of mood and appetite, i.e., the late luteal phase dysphoric disorder (DSM-III-R, appendix), or “the premenstrual syndrome” (PMS), and the major depression with seasonal pattern (DSM-III-R), or seasonal affective disorder (SAD). The reactive mood changes are frequently accompanied by features as hypersomnia, lethargy and increased appetite, particularly with a preference for carbohydrates. Central serotonin pathways participate in the regulation of mood and behavioural impulsivity, and modulate eating patterns qualitatively and quantitatively. Depressives with PMS og SAD benefit, in general, from treatments with serotonin potentiating drugs, suggesting that brain serotonin plays a role in the pathophysiology. Ingestion of carbohydrates increases the plasma ratio of tryptophan to other large neutral amino acids in man and animal, and the serotonin synthesis in the rat brain. Based on these findings it has been suggested that the excessive carbohydrate intake by patients with PMS and SAD reflects a selfmedication that temporarily relieves the vegetative symptoms via an increased central serotonergic activity.     

Influence of Carbohydrates on Secondary Metabolism in Fusarium avenaceum

Fusarium avenaceum is a widespread pathogen of important crops in the temperate climate zones that can produce many bioactive secondary metabolites, including moniliformin, fusarin C, antibiotic Y, 2-amino-14,16-dimethyloctadecan-3-ol (2-AOD-3-ol), chlamydosporol, aurofusarin and enniatins. Here, we examine the production of these secondary metabolites in response to cultivation on different carbon sources in order to gain insight into the regulation and production of secondary metabolites in F. avenaceum. Seven monosaccharides (arabinose, xylose, fructose, sorbose, galactose, mannose, glucose), five disaccharides (cellobiose, lactose, maltose, sucrose and trehalose) and three polysaccharides (dextrin, inulin and xylan) were used as substrates. Three F. avenaceum strains were used in the experiments. These were all able to grow and produce aurofusarin on the tested carbon sources. Moniliformin and enniatins were produced on all carbon types, except on lactose, which suggest a common conserved regulation mechanism. Differences in the strains was observed for production of fusarin C, 2-AOD-3-ol, chlamydosporol and antibiotic Y, which suggests that carbon source plays a role in the regulation of their biosynthesis.     

Carbohydrates and epithelial repair - more than just post-translational modification

Epithelia are the layers of cells that form barriers between external milieu and underlying tissues and thus, are important components of most organs of the body. Epithelial layers of organs, such as the lung, are exposed to various challenges resulting in frequent injury. Epithelial wound healing represents an important process by which repair restores the physical barrier lost as a result of cell damage and apoptosis. The repair of epithelial layers consists of a series of ordered events including epithelial cell spreading, migration proliferation and, differentiation. Carbohydrates attached to cell surface proteins and lipids can modulate the function of structures that they are conjugated to and therefore, can affect cell behavior. Although the basic mechanisms of epithelial repair are not entirely understood, many studies suggest glycoconjugates attached to proteins on the cell surface of epithelial cells play important roles in many of these cellular processes. In the present review, the role of carbohydrates in epithelial repair of different organs, including the sources of epithelial injury and current models of epithelial repair will be discussed with a focus on our understanding of the airway epithelium. With a better understanding of carbohydrates and their role in epithelial repair, new therapeutic targets for diseases involving damage to the epithelium can be identified.     

Carbohydrates and vaccines: from purified polysaccharides to semi-synthetic glycoconjugate vaccines

Over the last decades, capsular polysaccharides have been successfully used as antibacterial vaccines. Marketing several polysaccharide-protein conjugate vaccines filled the gap in many areas of children and infant vaccination. By facilitating access to structures of increasing complexity, recent progress in glycochemistry has enabled the design of more and more precisely defined glycoconjugate vaccines using synthetic saccharide components which mimic epitopes naturally implicated in protection. This strategy was recently validated in humans. It opens the way to new perspectives in vaccine research devoted to prophylactic and/or therapeutic applications against bacterial, fungal, parasitic or viral infections, and certain cancers.     

Botulinum Neurotoxin A Complex Recognizes Host Carbohydrates through Its Hemagglutinin Component

Botulinum neurotoxins (BoNTs) are potent bacterial toxins. The high oral toxicity of BoNTs is largely attributed to the progenitor toxin complex (PTC), which is assembled from BoNT and nontoxic neurotoxin-associated proteins (NAPs) that are produced together with BoNT in bacteria. Here, we performed ex vivo studies to examine binding of the highly homogeneous recombinant NAPs to mouse small intestine. We also carried out the first comprehensive glycan array screening with the hemagglutinin (HA) component of NAPs. Our data confirmed that intestinal binding of the PTC is partly mediated by the HA moiety through multivalent interactions between HA and host carbohydrates. The specific HA-carbohydrate recognition could be inhibited by receptor-mimicking saccharides.