Dextran sulfate, structure

Fig. 3 Structures of acharan sulfate, dextran sulfate, suramin, pentosan polysulfate, and phosphomannopentaose sulfate (PI-88). Representative saccharide units comprising each of these polymers are shown, where n is the degree of polymerization.

There is currently little understanding of the influence of interfacial composition and (nano)structure on the kinetics of enzymatic hydrolysis of biopolymers and lipids. However, a few preliminary studies are beginning to emerge (McClements et al., 2008 Dickinson, 2008). Thus, for example, Jourdain et al. (2009) have shown recently that, in a mixed5 sodium caseinate + dextran sulfate system, the measured interfacial viscosity increased from qs = 220 mN s m 1 without enzyme to qs = 950 mN s m 1 with trypsin present. At the same time, the interfacial elasticity was initially slightly reduced from (7S = 1.6 mN m 1 to (h = 0.7 mN m, although it later returned to close to its original value. Conversely, in the... 

Both pure dextran sulfates and mixed derivatives of dextran containing sulfate groups exhibit a broad spectrum of biological activities. The structural features of so-called mimetics of heparan sulfate are discussed in Sect. 5.2.2.1. The pure dextran sulfates used are almost exclusively commercial products with DS values above 2.0. 

It should be mentioned that the defined interaction of dextran sulfate with amino functions is not only applied for the design of structures on the su-permolecular level but also on the molecular level. Thus, a preferred handed helical structure was induced into the polyaniline main chains by chemical polymerisation of achiral aniline in the presence of dextran sulfate as a molecular template. This affords a novel chemical route for the synthesis of chiral conducting polymers [158]. 

Polysaccharides Hydrogen bonds and dipole-dipole interactions with hydroxyl groups of the sugar molecules are assumed to be the main interactions. In some cases, the helical structure of dextrins might be responsible for chiral recognition. Heparin, dextran sulfate, dermatan sulfate, streptomycin sulfate, amylose, chondroitin sulfate C, laminaran, dextrin sulfopropyl, and kanamycin sulfate. Doxylamine, laudanosine, naproxen, oxamniquine, pheniramine, primaquine, timepidium, trimetoquinol, etc. 

Many ionic poly(saccharides), such as heparin, chondroitin sulfates, dextran sulfate, and natural poly(saccharides), such as dextran, dextrin, pullulan, and their charged derivatives have been used as mobile phase additives for the separation of different enantiomers. Figure 10.10 [191,192,205,206]. Dextrins were found to have a wide application range, thought to be due in part to their helical structures. Enantiomer-chiral selector complexes seem to be weaker than for cyclodextrins, and it has not been demonstrated that enantiomer separations obtained by the poly(saccharide) chiral selectors cannot be obtained using cyclodextrins. Natural poly(saccharides) are typically complex mixtures of homologues and isomers, with a composition that can vary for different sources, resulting in differences in enantioselectivity. 

Amiel et al. [85, 86] investigated the formation of ternary complexes of a water soluble epichlorohydrin-linked f-CD polymer, cationic surfactant dodecyltrimethy-lammonium bromide (DTAB), and a polyanion sodium salt dextran sulfate (NaDxS) by viscometry and small angle neutron scattering. They proposed a structure of polyion complexes between NaDxS and the supramolecular polycation formed from fi-CD polymer and DTAB. More recently, Amiel et al. [87] have characterized in detail the supramolecular polycation. 

For example, polyaniline is not readily incorporated into wool structures, however, poly(2-methox-yaniline-5-sulfonic acid (PMAS) is (Figure 11.11). The PMAS can subsequently be used to template the aniline monomer before chemical oxidation. Biological molecules such as chondroitin sulfate, dextran sulfate, and DNA have been shown to be effective molecular templates for this purpose. 

CSY0073 applied in the range of 5 to 30 mg kg day to mice with dextran sulfate-induced colitis exerts anti-inflammatoty effects that both reduce signs of acute inflammation and also preserve intestinal wall structure. That this effect is not due to effects on intestinal bacteria has been demonstrated by comparison of fecal flora of healthy mice treated with either azithromycin or CSY0073. Thus, CSY0073 has no obvious effect on the composition of intestinal flora while azithromycin causes Gram positive organisms in particular to be reduced to less than 10% of the culturable... 

Levi, Hawkins and Hibbert6 have recently confirmed the structure for L. mesenteroides dextran proposed by Fowler, Buckland, Brauns and Hibbert.34 Completely methylated dextran in an over-all yield of 71% was obtained by three methylations with dimethyl sulfate and sodium hydroxide, followed by six modified Muskat methylations. The methylated dextran was hydrolyzed at 140° with methanolic hydrogen chloride, and the mixture of methylated glucosides, obtained in 95% yield, was quantitatively separated by fractional distillation. 2,3-Di-methyl-D-glucose was identified by means of the phenylhydrazide of the corresponding D-gluconic acid. 

The richest dietary sources of total iron are organ meats (liver and kidney), egg yolk, dried legumes, com, molasses and parsley. Liver is particularly valuable because of the high absorbability of its iron. However, only about 10% of dietary iron is absorbed. Iron deficiency anemia can be treated with soluble iron(II) compounds providing 200 mg in three or four daily divided doses. Oral iron(II) sulfate is the least expensive and is in wide use. Ascorbic acid increases the absorption efficiency of iron(II) sulfate. Parenteral administration of iron is used when oral iron is ineffective. Iron-dextran, a colloid formed from iron(III) chloride and an alkali-modified dextran, is one of several preparations available which has found extensive clinical use. It contains up to 28% Fe by weight and has a structural similarity to ferritin. Transfusion therapy may also be used in severe chronic anemia or acute hemorrhage. 

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