Hybrid Chains Research Articles

Solvothermal synthesis, crystal structures and photoluminescence properties of the novel Cd/X/α,ω-bis(benzotriazole)alkane hybrid family (X = Cl, Br and I)

Seven organic-inorganic hybrid solids, namely, [(CdI2)2(L1)2] (1), [(CdBr2)3(L1)2]n (2), [(CdCl2)5(L1)2]n (3), [(CdI2)(L2)]n (4), [(CdBr2)(L3)]n (5), [(CdBr2)2(L4)2]n (6), and [(CdI2)4(L4)4]n (7), have been obtained via the self-assembly of CdX2 (X = Cl, Br or I) with the four structurally related flexible organic ligands 1,2-bis(benzotriazole)ethane (L1), 1,3-bis(benzotriazole)propane (L2), 1,4-bis(benzotriazole)butane (L3) and 1,6-bis(benzotriazole)hexane (L4) under solvothermal conditions. Compound 1 presents a binuclear structure with a [Cd2N12C4] 18-membered cycle. In 2, the L1 ligands locate alternately on the two sides of the 1-D inorganic chain formed by papilionaceous [Cd2Br2] subunits. The 1-D hexagonal [CdCl2]n grid inorganic chains in 3 are generated by vertex-loss cubane-like [Cd3Cl4] motifs through sharing faces, which are further connected by L1 ligands to give a 2-D hybrid layer. For compound 4, the L2 ligands and 4-connected Cd centres link each other to give a 1-D single chain. In 5 and 6, [Cd2Br4] units are connected by L3 and L4 to generate a 2-D (4, 4) net and 1-D double chain structure, respectively. Four independent [CdI2] centres and four L4 ligands in 7 generate an extraordinarily large [Cd4N24C24] 52-membered cycle. The varying structures of 1–7 indicate that the spacer length of the bis(benzotriazole)alkane ligands and counter-anions play an essential role in the formation of the framework of the Cd(II) hybrid materials. Strong π–π stacking interactions between the benzotriazole ligands pack these low-dimensional hybrid chains or layers into high-dimensional supramolecular frameworks. The UV-vis diffuse reflectance spectra and solid state luminescence measurements show that compounds 1–7 are potential semiconductor and photoluminescence materials.

Structure of Pleiotrophin- and Hepatocyte Growth Factor-binding Sulfated Hexasaccharide Determined by Biochemical and Computational Approaches

Endogenous pleiotrophin and hepatocyte growth factor (HGF) mediate the neurite outgrowth-promoting activity of chondroitin sulfate (CS)/dermatan sulfate (DS) hybrid chains isolated from embryonic pig brain. CS/DS hybrid chains isolated from shark skin have a different disaccharide composition, but also display these activities. In this study, pleiotrophin- and HGF-binding domains in shark skin CS/DS were investigated. A high affinity CS/DS fraction was isolated using a pleiotrophin-immobilized column. It showed marked neurite outgrowth-promoting activity and strong inhibitory activity against the binding of pleiotrophin to immobilized CS/DS chains from embryonic pig brain. The inhibitory activity was abolished by chondroitinase ABC or B, and partially reduced by chondroitinase AC-I. A pentasulfated hexasaccharide with a novel structure was isolated from the chondroitinase AC-I digest using pleiotrophin affinity and anion exchange chromatographies. It displayed a potent inhibitory effect on the binding of HGF to immobilized shark skin CS/DS chains, suggesting that the pleiotrophin- and HGF-binding domains at least partially overlap in the CS/DS chains involved in the neuritogenic activity. Computational chemistry using molecular modeling and calculations of the electrostatic potential of the hexasaccharide and two pleiotrophin-binding octasaccharides previously isolated from CS/DS hybrid chains of embryonic pig brain identified an electronegative zone potentially involved in the molecular recognition of the oligosaccharides by pleiotrophin. Homology modeling of pleiotrophin based on a related midkine protein structure predicted the binding pocket of pleiotrophin for the oligosaccharides and provided new insights into the molecular mechanism of the interactions between the oligosaccharides and pleiotrophin.

Syntheses and Crystal Structures of Two Chloro‐Bridged Coordination Polymers [Cd(BIM)Cl2]n and [Pb(BIM)Cl2]n

AbstractTwo novel coordination polymers, [Cd(BIM)Cl2]n (1) and [Pb(BIM)Cl2]n (2) [wherein BIM = bis(imidazol‐1‐yl)methane], were synthesized by the reactions of the BIM ligand with CdCl2 and PbCl2, respectively. They were characterized by elemental analyses, IR, TGA and X‐ray single‐crystal diffraction techniques. Single‐crystal X‐ray structure analyses showed there is a pseudooctahedral arrangement around the cadmium atom in the complex 1. It has a three‐dimensional network which contains one‐dimensional inorganic‐organic hybrid chains and μ2‐bridging chloride ligands. A rare pentacoordinate square‐pyramidal arrangement was adopted for the lead(II) atom in the complex 2, which has an unusual two‐dimensional layer structure of macrometallacycles crosslinked with the bridging Pb2Cl2 units. The metal atoms in both complexes were coordinated with two BIM ligands in cis arrangement and bridged by μ2‐bridging chloride ligands.

Novel building units with bimetallic rings in inorganic/organic hybrid chains and layers

Hydrothermal synthesis has produced three new compounds constructed from novel building units containing vanadium-oxide (or oxyfluoride) subunits linked together via covalently bound cationic copper complexes. Each new compound exhibits novel structural features: [Cu(dipa)][VOF 4] ( 1) incorporates a corner-sharing octahedral vanadium(IV) oxyfluoride chain decorated by copper-(2,2′-dipyridyl amine) complexes which form intra-chain bridges. Within a similar reactant system [Cu(dipa)] 2[V 6O 17] ( 2) is produced, the structure of which exhibits edge-sharing trigonal bipyramidal vanadium(V) ‘ladder-like’ double chains which are bridged into layers by tetrahedral pyrovanadate dimers together with the copper-(2,2′-dipyridyl amine) complexes. [Cu(py) 4] 2[V 4O 12] ( 3), is a 2-D structure featuring exclusively tetrahedral vanadium(V) in four-membered ring building blocks, linked through octahedral copper-pyridine complexes to form two crystallographically different bimetallic layers.

Dynamic Modeling Method of Parallel Robot with Hybrid Chains

Parallel robot with hybrid chains has many advantages such as independent motion outputs,high stiffness and control decoupling,but the existence of the close-loop in the chain also increases the difficulties of kinematic analysis and dynamic analysis. The dynamic modeling method for parallel robot with hybrid chains based on the principle of virtual work and equivalent tree structure is proposed by disconnecting the platform and the chains as well as degenerating hybrid chain into serial chain or tree chain, the closed-form solutions for the inverse and direct dynamic models of parallel robot with hybrid chains are derived,the dimension of dynamic model is equal to the degrees of freedom of the robot,the minimal inertial parameters and recursive Newton-Euler method can be utilized to reduce the computation time of inverse dynamic model of the chain.The method is applied to the kinematic analysis and dynamic analysis of two parallel robots with hybrid chains (2-P(P_a)R-1-PUU and 3-PU~*) and is applicable for all kinds of parallel robots with hybrid chains,it can instruct structure parameter design and actuator selection of parallel robot with hybrid chains and can be used for real-time dynamic control of the robot.

Organic–inorganic hybrid chains and layers constructed from copper-amine cations and early transition metal (Nb, Mo) oxyfluoride anions

Under hydrothermal conditions in HF-containing media, the combination of early (Nb(5+), Mo(6+)) and late (Cu(2+)) transition metals with four different organic amine ligands yields eight novel hybrid compounds with chain and layer structures. The eight new compounds were synthesised from a systematic series of reactions and can be subdivided into four pairs, the topologies of which are essentially unique to each ligand, containing in each case a Cu-based cationic species, but alternately either [MoO(2)F(4)](2-) or [NbOF(5)](2-), in an isomorphous manner, as the anionic moiety. The overall structures of theses materials reflect the influences of the organo amine ligands. [Cu(C(2)H(4)N(4))(2)][MoO(2)F(4)].H(2)O () and [Cu(C(2)H(4)N(4))(2)][NbOF(5)].H(2)O () exhibit an infinite copper fluoride amine chain, while the anionic moieties act as 'decoration' to the chain. [Cu(C(3)H(4)N(2))(4)][MoO(2)F(4)] () and [Cu(C(3)H(4)N(2))(4)][NbOF(5)] () form infinite 1D chains with alternating cationic and anionic units. [Cu(2)F(2)(C(10)H(9)N(3))(2)][MoO(2)F(4)] () and [Cu(2)F(2)(C(10)H(9)N(3))(2)] [NbOF(5)] () contain a dimeric copper fluoride complex, bridged through anions to form a 1D infinite chain. [Cu(C(10)H(8)N(2))(2)(H(2)O)(2)][MoO(2)F(4)] () and [Cu(C(10)H(8)N(2))(2)(H(2)O)(2)][NbOF(5)] () contain a 2D interpenetrated network formed from the copper-4,4'-bipy complex, with open channels which accommodate the oxyfluoride anions via hydrogen bond interactions.

Rare occurrence of Hb Lepore-Baltimore in African Americans: molecular characteristics and variations of Hb Lepores

Hb Lepore is the hybrid hemoglobin (Hb) composed of two alpha-globin chains and two deltabeta hybrid chains and is associated with the clinical findings of thalassemia minor in its heterozygous form. Hb Lepore can be found in many ethnic groups, commonly in southern European countries, but rarely in African Americans. The first Hb Lepore case in an African-American individual was named Hb Lepore-The Bronx (Hb Lepore-Boston). Hb Lepore-Washington-Boston and Hb Lepore-Baltimore with a breakpoint of (delta50Ser/beta86Ala) were later reported. In this paper, we describe an Hb Lepore-Baltimore (delta68Leu/beta84Thr) deltabeta-fusion gene with a different breakpoint detected for the first time in an African-American female. We have used state-of-the-art technology, combining protein- and DNA-based methods, in the analysis of the hybrid hemoglobin and discuss its molecular characteristics.

Two Extended Organic‐Inorganic Assemblies Based on Polyoxometalates and Copper Coordination Polymers with Mixed 4,4′‐Bipyridine and 2,2′‐Bipyridine Ligands

AbstractTwo new organic‐inorganic hybrid compounds {CuII4Cl(2,2′‐bipy)4(4,4′‐bipy)3(4,4′‐Hbipy)2[PMo12O40]}[PMo12O40]2·2H2O (1) and [CuI2(2,2′‐bipy)2(4,4′‐bipy)][CuI1.5(2,2′‐bipy)(4,4′‐bipy)]2[H3W12O40] (2) (2,2′‐bipy = 2,2′‐bipyridine, 4,4′‐bipy = 4,4′‐bipyridine) have been synthesised and subsequently characterised by elemental analysis, IR spectroscopy, thermal gravimetric analysis (TGA), electrochemical measurements and single‐crystal X‐ray diffraction. The most interesting feature of compound 1 is the Cu–Cl bond in the mixed ligand complex. Furthermore, 1 shows a 2D grid layered structure constructed from the [PMo12O40]3– polyoxoanion building units and 1D [Cu4(2,2′‐bipy)4(4,4′‐bipy)5Cl]nn– hybrid chains which are decorated by dangling polyoxoanion clusters that are disposed in a mutual anti orientation with respect to the layer plane. As fas as we know, compound 1 is the first characterised 2D structure with polyoxometalate clusters as pendants. Compound 2 represents the first 1D structure formed by ispolyoxotungstate building blocks [H2W12O40]6– and transition metal complex fragments with mixed ligands.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Identification of Further Elongation and Branching of Dimeric Type 1 Chain on Lactosylceramides from Colonic Adenocarcinoma by Tandem Mass Spectrometry Sequencing Analyses

Mammalian glycan chain elongation is mostly based on extending the type 2 chain, Galbeta1-4GlcNAc, whereas the corresponding type 1 chain, Galbeta1-3GlcNAc, is not normally extended. In a broader context of developing high sensitivity mass spectrometry methodologies for glycomic identification of Le(a) versus Le(x) and linear versus branched poly-N-acetyllactosamine (polyLacNAc), we have now shown that the dimeric type 1 glycan chain, as carried on the lactosylceramides of a human colonic adenocarcinoma cell line, Colo205, not only can be further extended linearly but can likewise be branched at C6 of 3-linked Gal in a manner similar to polyLacNAc. A combination of chemical and enzymatic derivatization coupled with advanced mass spectrometry analyses afforded unambiguous identification of a complex mixture of type 1 and 2 hybrids as well as those fucosylated variants founded exclusively on linear and branched trimeric type 1 chain. We further showed by in vitro enzymatic synthesis that extended type 1 and the hybrid chains can be branched by all three forms of the human I branching enzymes (IGnT) currently identified but with lower efficiency and stringency with respect to branching site preference. Importantly, it was found that a better substrate is one that carries a Gal site for branching that is extended at the non-reducing end by a type 2 and not a type 1 unit, whereas the IGnTs are less discriminative with respect to whether the targeted Gal site is itself beta3- or beta4-linked to GlcNAc at the reducing end.

Determination of iduronic acid and glucuronic acid in sulfated chondroitin/dermatan hybrid chains by 1H-nuclear magnetic resonance spectroscopy

The relative proportion of L: -iduronic acid (IdoA) and D: -glucuronic acid (GlcA) is of great importance for the structure-function relationship of chondroitin sulfate (CS)/dermatan sulfate (DS). However, determination of the isotypes of uronic acid residues in CS/DS is still a challenge, due to the instability of free uronic acid released by chemical degradation and its conversion to unsaturated uronic acid by digestion with bacterial eliminase. (1)H-Nuclear magnetic resonance (NMR) spectroscopy is a promising tool with which to address this issue, but the traditional method based on the assignment of the ring proton signals of IdoA and GlcA residues still has drawbacks such as the serious overlap of signals in the (1)H-NMR spectrum of CS/DS polysaccharides. We found that the proton signals of the N-acetyl group of N-acetyl-D: -galactosamines in CS and DS could be clearly distinguished and accurately integrated in the one-dimensional (1D) (1)H-NMR spectrum. Based on this finding, here we report a novel, sensitive, and nondestructive 1D (1)H-NMR-based method to determine the proportion of IdoA and GlcA residues in CS/DS hybrid chains.

Recent Advances in the Structural Study of Functional Chondroitin Sulfate and Dermatan Sulfate in Health and Disease

Chondroitin sulfate (CS) dermatan sulfate (DS), and CS/DS hybrid chains are biologically active like heparan sulfate, and structurally the most complex species of the glycosaminoglycan family along with heparan sulfate. They exist at the cell surface and extracellular matrix in the form of proteoglycans. They function as regulators of functional proteins such as growth factors, cytokines, chemokines, adhesion molecules, and lipoproteins through interactions with the ligands of these proteins via specific saccharide domains. Structural alterations have been often implicated in pathological conditions, such as cancer and atherosclerosis. Recent microsequencing of CS/DS oligosaccharides that bind growth factors, such as pleiotrophin, and various monoclonal antibodies against CS/DS, have revealed a considerable number of unique oligosaccharide sequences. This review focuses on recent advances in the study of the structure-function relation of CS, DS and their hybrid chains in physiological and pathological conditions.

Synthesis, Crystal Structure, and Properties of a Supramolecular Compound Based on Waugh-type Polyanion and Moroxydine

Abstract A supramolecular compound Na3(HABOB)(H2ABOB)[MnMo9O32]·5.5H2O (ABOB = moroxydine) has been synthesized and characterized by elemental analyses, IR spectrum, diffuse reflectance spectrum, room temperature magnetic moment, single crystal X-ray diffraction, and TG analysis. It exhibits a two-dimensional, layered inorganic framework constructed from Waugh-type polyanions [MnMo9O32]6− and Na+ ions linkers. Protonated ABOB molecules are hydrogen-bonded to the left- and right- handed [MnMo9O32]6− enantiomorphs to construct two kinds of infinite organic–inorganic hybrid chains.

Neuritogenic Activity of Chondroitin/Dermatan Sulfate Hybrid Chains of Embryonic Pig Brain and Their Mimicry from Shark Liver: INVOLVEMENT OF THE PLEIOTROPHIN AND HEPATOCYTE GROWTH FACTOR SIGNALING PATHWAYS

Accumulating evidence suggests the involvement of chondroitin sulfate (CS) and dermatan sulfate (DS) hybrid chains in the brain's development and critical roles for oversulfated disaccharides and IdoUA residues in the growth factor-binding and neuritogenic activities of these chains. In the pursuit of sources of CS/DS with unique structures, neuritogenic activity, and therapeutic potential, two novel CS/DS preparations were isolated from shark liver by anion exchange chromatography. The major (80%) low sulfated and minor (20%) highly sulfated fractions had an average molecular mass of 3.8-38.9 and 75.7 kDa, respectively. Digestion with various chondroitinases (CSases) revealed a large panel of disaccharides with either GlcUA or IdoUA scattered along the polysaccharide chains in both of the fractions. The higher M(r) fraction, richer in IdoUA(2-O-sulfate)alpha1-3GalNAc(4-O-sulfate) and GlcUAbeta/IdoUAalpha1-3GalNAc(4,6-O-disulfate) units, exerted greater neurite outgrowth-promoting (NOP) activity and better promoted the binding of various heparin-binding growth factors, including pleiotrophin (PTN), midkine, recombinant human heparin-binding epidermal growth factor-like growth factor, VEGF(165), fibroblast growth factor-2, fibroblast growth factor-7, and hepatocyte growth factor (HGF). These activities were largely abolished by digestion with CSase ABC or B but only moderately affected by a mixture of CSases AC-I and AC-II. In addition, the NOP activity of the larger fraction was markedly reduced by desulfation with alkali, suggesting a role for the 2-O-sulfate of IdoUA(2-O-sulfate)alpha1-3GalNAc(4-O-sulfate). The NOP activity of the higher molecular weight fraction and that of the embryonic pig brain-derived CS/DS fraction were also sup pressed to a large extent by antibodies against HGF, PTN, and their individual receptors cMet and anaplastic lymphoma kinase, revealing the involvement of the HGF and PTN signaling pathways in the activity.

Identification and distribution of chondroitin sulfate in the three electric organs of the electric eel, Electrophorus electricus (L.)

The electrogenic tissue of the electric eel Electrophorus electricus (L.) is distributed in three well-defined electric organs, the Main electric organ, Sach's organ and Hunter's organ. Sulfated glycosaminoglycan (GAG) composition was characterized in the three electric organs of the electric eel. Sulfated GAGs were analyzed in the electric organs using metachromatic staining, biochemical analysis including electrophoresis before and after specific enzymatic or chemical degradations, and immunostaining with an antibody against chondroitin sulfate (CS). Our results showed in the three electric organs that CS was the main sulfated GAG species detected, accompanied by small and diminutive amounts of CS/dermatan sulfate hybrid chains and heparan sulfate (HS), respectively. However, HS was not detected in the Sach's organ. CS was predominantly detected in the innervated membrane face of the electroplaques in the three electric organs. Our findings extend previous observations on the GAG composition in the electric organs of E. electricus and provide new information regarding the tissue distribution and location of CS.

Chondroitin Sulfate/Dermatan Sulfate Hybrid Chains in the Development of Cerebellum: SPATIOTEMPORAL REGULATION OF THE EXPRESSION OF CRITICAL DISULFATED DISACCHARIDES BY SPECIFIC SULFOTRANSFERASES

Chondroitin sulfate/dermatan sulfate (CS/DS) chains regulate the development of the central nervous system in vertebrates. Previously, we demonstrated that CS/DS hybrid chains from embryonic pig brain exhibit neuritogenic and growth factor binding activities, which depended on their IdoUA content defining the DS-like structure. To elucidate the distribution of such functional sugar chains during the development of the brain, in situ hybridization was performed to examine expression of three CS/DS GalNAc 4-O-sulfotransferases, D4ST-1, C4ST-1, and C4ST-2, and a single uronyl 2-O-sulfotransferase (UST) involved in the biosynthesis of DS in addition to CS intermediates. C4ST-1 and C4ST-2 were ubiquitously expressed in the postnatal mouse brain, whereas the expression of D4ST-1 and UST was restricted in the developing cerebellum and culminated at postnatal day 14 as shown by reverse transcriptase-PCR analysis. In situ analysis of the disaccharides of CS/DS in brain sections revealed that the concentration of CS/DS increases 2-fold during development (postnatal day 7 to 7 weeks). The proportions of DS-specific, principal disaccharides, IdoUA-Gal-NAc(4-O-sulfate) (iA) and IdoUA(2-O-sulfate)-GalNAc(4-O-sulfate) (iB), produced by the sequential actions of D4ST-1 and UST, were higher in the CS/DS chains from cerebellum than those from whole brain sections. A dramatic increase (10-fold) in the proportion of iB during development was noteworthy. In contrast, GlcUA/IdoUA(2-O-sulfate)-GalNAc(6-O-sulfate) (D/iD) and GlcUA/IdoUA-GalNAc(4, 6-O-disulfate) (E/iE) decreased to 50 and 30%, respectively, in the developing cerebellum. These results suggest that the IdoUA-containing iA and iB units along with D/iD and E/iE units in the CS/DS hybrid play important roles in the formation of the cerebellar neural network during postnatal brain development.

A Two‐Dimensional Porphyrin‐Based Porous Network Featuring Communicating Cavities for the Templated Complexation of Fullerenes

An unprecedented two-dimensional porphyrin network featuring dynamic pores capable of hosting fullerenes is realized following a bottom-up approach at a single-crystal silver surface. Surface- and porphyrin-driven long-range interactions between the C-60 guest molecules and porphyrin layer result in the formation of exceptionally large supramolecular hybrid chains and islands (see Figure and Cover).

Demonstration of the Pleiotrophin-binding Oligosaccharide Sequences Isolated from Chondroitin Sulfate/Dermatan Sulfate Hybrid Chains of Embryonic Pig Brains

Mammalian brains contain significant amounts of chondroitin sulfate (CS), dermatan sulfate (DS), and CS/DS hybrid chains. CS/DS chains isolated from embryonic pig brains (E-CS/DS) promote the outgrowth of neurites in embryonic mouse hippocampal neurons in culture by interacting with pleiotrophin (PTN), a heparin-binding growth factor. Here, we analyzed oligosaccharides isolated from E-CS/DS, which showed that octasaccharides were the minimal size capable of interacting with PTN at a physiological salt concentration. Five and eight sequences were purified from fluorescently labeled PTN-bound and -unbound octasaccharide fractions, respectively, by enzymatic digestion followed by PTN-affinity chromatography. Their sequences were determined by enzymatic digestion in conjunction with high performance liquid chromatography, revealing a critical role for oversulfated D and/or iD disaccharides in the low yet significant affinity for PTN, which is required for neuritogenesis. The critical D and iD units are GlcUA(2-O-sulfate)beta1-3GalNAc(6-O-sulfate) and IdoUA(2-O-sulfate)alpha1-3GalNAc(6-O-sulfate), respectively, where IdoUA represents L-iduronic acid. In contrast, high affinity interactions with PTN required decasaccharides with E units (GlcUAbeta1-3GalNAc(4, 6-O-disulfate)), B units (GlcUA(2-O-sulfate)beta1-3GalNAc(4-O-sulfate)), and/or their IdoUA-containing counterparts (iE and iB) in addition to D/iD units, although the biological significance of such strong interactions remains to be investigated. Thus, chain size and composition are crucial to the interaction with PTN, and PTN binds to multiple sequences in E-CS/DS chains with distinct affinity. Notably, not only heparan sulfate but also CS/DS hybrid chain structures of mammalian brains contain a high degree of microheterogeneity with a cluster of oversulfated disaccharides and appear to play roles in regulating the functions of PTN.

Novel composite polymer electrolyte comprising poly(ethylene oxide) and triblock copolymer/mesostructured silica hybrid used for lithium polymer battery

Ordered mesoporous materials, due to its potential applications in catalysis, separation technologies, and nano-science have attracted much attention in the past few years. In this work, a novel PEO-based composite polymer electrolyte by using organic–inorganic hybrid EO 20PO 70EO 20 @ mesoporous silica (P123 @ SBA-15) as the filler has been developed. The interactions between P123 @ SBA-15 hybrid and PEO chains are studied by X-ray diffraction (XRD), differential scanning calorimeter (DSC), and FT-IR techniques. The effects of P123 @ SBA-15 on the electrochemical properties of the PEO-based electrolyte, such as ionic conductivity, lithium ion transference number are studied by electrochemical ac impedance spectroscopy and steady-state current method. The experiment results show that P123 @ SBA-15 can enhance the ionic conductivity and increase the lithium ion transference number of PEO-based electrolyte, which are induced by the special topology structure of P123 in P123 @ SBA-15 hybrid, at the same time. The excellent lithium transport properties and broad electrochemical stability window suggesting that PEO–LiClO 4/P123 @ SBA-15 composite polymer electrolyte can be used as candidate electrolyte materials for lithium polymer batteries.

Heparin-binding Growth Factor, Pleiotrophin, Mediates Neuritogenic Activity of Embryonic Pig Brain-derived Chondroitin Sulfate/Dermatan Sulfate Hybrid Chains

Chondroitin sulfate (CS) and dermatan sulfate (DS) chains play roles in the central nervous system. Most notably, CS/DS hybrid chains (E-CS/DS) purified from embryonic pig brains bind growth factors and promote neurite outgrowth toward embryonic mouse hippocampal neurons in culture. However, the neuritogenic mechanism is not well understood. Here we showed that pleiotrophin (PTN), a heparin-binding growth factor, produced mainly by glia cells, was the predominant binding partner for E-CS/DS in the membrane-associated protein fraction of neonatal rat brain. The CS/DS chains were separated on a PTN column into unbound, low affinity, and high affinity fractions. The latter two fractions promoted outgrowth of dendrite- and axon-like neurites, respectively, whereas the unbound fraction showed no such activity. The activity of the low affinity fraction was abolished by an anti-PTN antibody or when glia cells were removed from the culture. In contrast, the high affinity fraction displayed activity under both these conditions. Hence, PTN mainly from glia cells mediated the activity of the low affinity but not the high affinity fraction. The anti-CS antibody 473HD neutralized the neuritogenic activities of both fractions. Interaction analysis indicated that the 473HD epitope and PTN-binding domains in the E-CS/DS chains largely overlap. The three affinity subfractions differed in disaccharide composition and the distribution of l-iduronic acid-containing disaccharides along the chains. Oversulfated disaccharides and nonconsecutive iduronic acid-containing units were the requirements for the E-CS/DS chains to bind PTN and to exhibit the neuritogenic activities. Thus, CS subpopulations with distinct structures in the mammalian brain play different roles in neuritogenesis through distinct molecular mechanisms, at least in part by regulating the functions of growth factors.

Novel 70-kDa Chondroitin Sulfate/Dermatan Sulfate Hybrid Chains with a Unique Heterogenous Sulfation Pattern from Shark Skin, Which Exhibit Neuritogenic Activity and Binding Activities for Growth Factors and Neurotrophic Factors

Chondroitin sulfate (CS) and dermatan sulfate (DS) hybrid chains of proteoglycans are critical in growth factor binding, neuritogenesis, and brain development. Here we isolated CS/DS hybrid chains from shark skin aiming to develop therapeutic agents. Digestion with various chondroitinases showed that both GlcUA- and IdoUA-containing disaccharides are scattered along the polysaccharide chains with an unusually large average molecular mass of 70 kDa. The CS/DS chains were separated into major (80%) and minor (20%) fractions by anion-exchange chromatography. Both fractions had relatively low degrees of sulfation (sulfate/disaccharide molar ratio=1.17 versus 0.87), showing a unique feature compared with the marine CS and DS isolated to date, most of which are oversulfated. They were highly heterogeneous and characterized by multiple disaccharides including GlcUA-GalNAc, GlcUA-GalNAc(6S), GlcUA-GalNAc(4S), IdoUA-GalNAc(4S), GlcUA-GalNAc(4S,6S), IdoUA-GalNAc(4S,6S), GlcUA(2S)-GalNAc(6S), and/or IdoUA(2S)-GalNAc(6S), IdoUA(2S)-GalNAc(4S) and novel GlcUA(2S)-GalNAc(4S), where 2S, 4S, and 6S represent 2-O-, 4-O- and 6-O-sulfate, respectively. The CS/DS chains bound two neurotrophic factors and various growth factors expressed in the brain with high affinity as evaluated for the major fraction by kinetic analysis using a surface plasmon resonance detector, and also promoted the outgrowth of neurites of both an axonic and a dendritic nature. The neuritogenic activity was abolished completely by digestion with chondroitinase ABC, AC-I, or B, suggesting the importance of both GlcUA- and IdoUA-containing moieties. It also showed anti-heparin cofactor II activity comparable to that exhibited by DS from porcine skin. Thus, by virtue of its unique structure and biological activities, DS will find a potential use in therapeutics.