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16339081 | Syntaxins 3 and 4 are concentrated in separate clusters on the plasma membrane before the establishment of cell polarity. | Syntaxins 3 and 4 localize to the apical and basolateral plasma membrane, respectively, of epithelial cells where they mediate vesicle fusion. Here, we report that before establishment of cell polarity, syntaxins 3 and 4 are confined to mutually exclusive, submicron-sized clusters. Syntaxin clusters are remarkably unif... |
16547537 | Directed supramolecular assembly of Cu(II)-based "paddlewheels" into infinite 1-D chains using structurally bifunctional ligands. | The construction of Cu(II)-containing supramolecular chains is achieved by combining suitable anionic ligands (for controlling the coordination geometry and for creating a neutral building block) with four new bifunctional ligands containing a metal-coordinating pyridyl site and a self-complementary hydrogen-bonding mo... |
16462949 | Synthesis, structure and hydrosilylation activity of neutral and cationic rare-earth metal silanolate complexes. | Rare-earth metal alkyl tri(tert-butoxy)silanolate complexes [Ln{mu,eta2-OSi(O(t)Bu)3}(CH2SiMe3)2]2 (Ln = Y (1), Tb (2), Lu (3)) were prepared via protonolysis of the appropriate tris(alkyl) complex [Ln(CH2SiMe3)3(thf)2] with tri(tert-butoxy)silanol in pentane. Crystal structure analysis revealed a dinuclear structure f... |
16401406 | Efficient size control of amphiphilic cyclodextrin nanoparticles through a statistical mixture design methodology. | <h4>Purpose</h4>the aim of the study was to investigate size control of amphiphilic beta-cyclodextrin nanoparticles obtained by solvent displacement technique.<h4>Methods</h4>An experimental design methodology for mixture design was undertaken using D-optimal approach with the following technique variables: water fract... |
16337214 | Analysis of catechins in Theobroma cacao beans by cyclodextrin-modified micellar electrokinetic chromatography. | A micellar electrokinetic chromatography (MEKC) method was developed for the quantitation of polyphenols (+)-catechin and (-)-epicatechin (catechin monomers) and the methylxanthine theobromine in Theobroma cacao beans. Owing to the poor stability of catechin monomers in alkaline conditions, a 50 mM Britton-Robinson buf... |
17761249 | Self assembled monolayers on silicon for molecular electronics. | We present an overview of various aspects of the self-assembly of organic monolayers on silicon substrates for molecular electronics applications. Different chemical strategies employed for grafting the self-assembled monolayers (SAMs) of alkanes having different chain lengths on native oxide of Si or on bare Si have b... |
16496049 | An electrochemical immunosensor using ferrocenyl-tethered dendrimer. | We report here an enzyme-amplified, sandwich-type immunosensor for detecting the biospecific interaction between an antibody and antigen using redox mediation. We employed biotin/anti-biotin IgG as a model immunosensing pair. Partially ferrocenyl-tethered dendrimer (Fc-D), whose ferrocene moiety acts as a redox mediato... |
16462950 | Supramolecular architectures assembled by the interaction of purine nucleobases with metal-oxalato frameworks. Non-covalent stabilization of the 7H-adenine tautomer in the solid-state. | The synthesis, crystal structure and variable-temperature magnetic measurements of the compounds [Mn(mu-ox)(H2O)(7H-pur-kappaN9)]n (1), {[Mn(mu-ox)(H2O)2].(7H-ade).(H2O)}n (2) and {[Cu(mu-ox)(H2O)(7H-ade-kappaN9)][Cu(mu-ox)(mu-H2O)(7H-ade-kappaN9)]. approximately 10/3H2O}n (3), (where ox: oxalato dianion, pur: purine, ... |
16337084 | The compartmentalization of prolactin signaling in the mouse mammary gland. | In mammary epithelial cells, prolactin (PRL) activates at least two signaling pathways: Jak/Stat and nitric oxide (NO). The former induces differentiation as measured by alpha-lactalbumin accumulation, while experiments with sodium nitroprusside (SNP) show that NO inhibits differentiation. In order to resolve this appa... |
16330763 | Polyproline II propensities from GGXGG peptides reveal an anticorrelation with beta-sheet scales. | There is growing appreciation of the functional relevance of unfolded proteins in biology. However, unfolded states of proteins have proven inaccessible to the usual techniques for high-resolution structural and energetic characterization. Unfolded states are still generally conceived of as statistical coils, based on ... |
16330748 | Peripheral B cells latently infected with Epstein-Barr virus display molecular hallmarks of classical antigen-selected memory B cells. | Epstein-Barr virus (EBV) establishes a lifelong persistent infection within peripheral blood B cells with the surface phenotype of memory cells. To date there is no proof that these cells have the genotype of true germinal-center-derived memory B cells. It is critical to understand the relative contribution of viral mi... |
18404516 | ATP release via anion channels. | ATP serves not only as an energy source for all cell types but as an 'extracellular messenger' for autocrine and paracrine signalling. It is released from the cell via several different purinergic signal efflux pathways. ATP and its Mg(2+) and/or H(+) salts exist in anionic forms at physiological pH and may exit cells ... |
18970584 | Cyclodextrin assisted nanophase determination of alkaloid salts. | The poor water solubility of the free base and the high dissociation constant (K(a)) hinder mainly the assay of alkaloid salts. We have elaborated an environment friendly method that can be carried out in aqueous media. The stability difference of the cyclodextrin (CD) complexes of free and protonated bases were used f... |
16391734 | Efficient single-layer electroluminescent device based on a bipolar emitting boron-containing material. | A novel multifunctional 1,6-bis(2-hydroxyphenyl)pyridine boron bis(4-n-butyl-phenyl)phenyleneamine compound in which the hole-transporting (HT), electron-transporting (ET), and emitting (EM) components are integrated into a single molecule was synthesized and used as an emitting material to fabricate an efficient singl... |
16330250 | Spectrofluorimetric study on the inclusion interaction between lomefloxacin and p-sulfonated calix[4]arene and its analytical application. | The characteristics of host-guest complexation between p-sulfonated calix[4]arene (SC4A) and lomefloxacin (LMFX) were investigated by fluorescence spectrometry. A 1:1 stoichiometry for the complexation was established and an association constant of 6.48x10(4) l mol-1 at 25 degrees C was calculated by applying a deduced... |
16326915 | Self-assembly of actin scaffolds at ponticulin-containing supported phospholipid bilayers. | Phospholipid vesicles containing ponticulin have been used to form solid supported and tethered bilayer lipid membranes. The ponticulin serves as both a nucleation site for actin polymerization as well as a binding site for F-actin. Studies of F-actin binding to such bilayers have demonstrated the formation of an in vi... |
16326912 | The intrinsic flexibility of the Kv voltage sensor and its implications for channel gating. | Analysis of the crystal structures of the intact voltage-sensitive potassium channel KvAP (from Aeropyrum pernix) and Kv1.2 (from rat brain), along with the isolated voltage sensor (VS) domain from KvAP, raises the question of the exact nature of the voltage-sensing conformational change that triggers activation of Kv ... |
16326908 | Glycolytic enzyme interactions with yeast and skeletal muscle F-actin. | Interaction of glycolytic enzymes with F-actin is suggested to be a mechanism for compartmentation of the glycolytic pathway. Earlier work demonstrates that muscle F-actin strongly binds glycolytic enzymes, allowing for the general conclusion that "actin binds enzymes", which may be a generalized phenomenon. By taking ... |
16326904 | Structural investigation of bilayers formed by 1-palmitoyl-2-oleoylphosphatidylnucleosides. | Bilayers of palmitoyl-oleoylphosphatidylnucleoside derivatives (1-palmitoyl-2-oleoyl-phosphatidyl-adenosine and 1-palmitoyl-2-oleoyl-phosphatidyl-uridine) were synthesized and investigated in the low-water content regime by a combination of neutron diffraction and Fourier transform infrared linear dichroism (LD-FTIR). ... |
16326715 | NMR solution structure of the tandem Src homology 3 domains of p47phox complexed with a p22phox-derived proline-rich peptide. | The phagocyte NADPH oxidase plays a crucial role in host defense against microbial infections by generating reactive oxygen species. It is a multisubunit enzyme composed of membrane-bound flavocytochrome b558 as well as cytosolic components, including p47phox, which is essential for assembly of the complex. When phagoc... |
16325788 | Solubility of cyclomaltooligosaccharides (cyclodextrins) in H2O and D2O: a comparative study. | Cyclomaltooligosaccharides (cyclodextrins, CDs) are cyclic oligomers having six, seven, or eight units of alpha-D-glucose, named as cyclomaltohexaose (alpha-CD), cyclomaltoheptaose (beta-CD) and cyclomaltooctaose (gamma-CD), respectively. The molecule of CD has a cavity in which the interior is hydrophobic relative to ... |
23345922 | The possibility of the formation of protocells and their structural components on the basis of the apatite matrix and cocrystallizing minerals. | This paper presents the author's theory on the possibility of simultaneous hard-phase synthesis of various organic molecules from gas-phase elements on the basis of the apatite matrix and cocrystallizing minerals (carbonate-apatite, calcite, mica). These molecules and their ensembles gave rise to living systems and pro... |
23345912 | Gravitational symmetry breaking leads to a polar liquid crystal phase of microtubules in vitro. | Recent space-flight experiments performed by Tabony's team provided further evidence that a microgravity environment strongly affects the spatio-temporal organization of microtubule assemblies. Characteristic time and length scales were found that govern the organization of oriented bundles under Earth's gravitational ... |
23345909 | Protein surface dynamics: interaction with water and small solutes. | Previous time resolved measurements had indicated that protons could propagate on the surface of a protein, or a membrane, by a special mechanism that enhances the shuttle of the proton towards a specific site [1]. It was proposed that a proper location of residues on the surface contributes to the proton shuttling fun... |
23345908 | A spectroscopic study of structural heterogeneity and carbon monoxide binding in neuroglobin. | Neuroglobin (Ngb) is a small globular protein that binds diatomic ligands like oxygen, carbon monoxide (CO) and nitric oxide at a heme prosthetic group. We have performed FTIR spectroscopy in the infrared stretching bands of CO and flash photolysis with monitoring in the electronic heme absorption bands to investigate ... |
23345899 | Can we model DNA at the mesoscale? | Modelling DNA is useful for understanding its properties better but it is also challenging because many of these properties involve hundreds of base pairs or more, or time scales which are much longer than the time scales accessible to molecular dynamics. It is therefore necessary to develop models at a mesoscale, whic... |
21991003 | Clinical and Autopsy Diagnoses of Visceral Affections of Patients Who Died Because of Complicated Burns with Multi-organ Failure. | The anatomicopathological investigations carried out in a total number of 186 cadavers during the last decade were reviewed. In these retrospective studies of necropsy protocols related to different affections of visceral organ systems that evolved asymptomatically, 30.1% involved the neurological system, 36.0% the uro... |
18833337 | Synthesis and Conformations of Dendronized Poly(L-lysine). | Dendronized polymers based on a poly(L-lysine) backbone have been synthesized up to the fourth generation. The hydroxyl-terminated polymers are completely water-soluble, which makes them good candidates for drug delivery applications. The dendronized polypeptide backbones are helical at lower generations, but undergo a... |
18167569 | Co-expression of zinc binding motif and GFP as a cellular indicator of metal ions mobility. | A significant role of zinc-binding motifs on metal mobility in Escherichia coli was explored using a chimeric metal-binding green fluorescent protein (GFP) as an intracellular zinc indicator. Investigation was initiated by co-transformation and co-expression of two chimeric genes encoding the chimeric GFP carrying hexa... |
17191959 | N-linked glycosylated beta-peptides are resistant to degradation by glycoamidase A. | Beta-peptides are resistant to degradation by a variety of proteolytic enzymes that rapidly degrade natural alpha-peptides. This is one of many characteristics that make beta-peptides an attractive class of compounds for drug discovery efforts. To further understand the molecular recognition properties of beta-peptides... |
16921680 | Analysis of molecular stereoelectronic similarity between N,N-diethyl-m-toluamide (DEET) analogs and insect juvenile hormone to develop a model pharmacophore for insect repellent activity. | Similarity analysis on molecular stereoelectronic properties of N,N-diethyl-m-toluamide (DEET), natural insect juvenile hormone (JH), a synthetic insect juvenile hormone mimic (JH-mimic, undecen-2-yl carbamate), and DEET compounds reveals remarkable similarities that lead to a reliable pharmacophore for the design of e... |
16863114 | Energy transfer within Zn-porphyrin dendrimers: study of the singlet-singlet annihilation kinetics. | In this article, we explore energy transfer processes within a series of Zn-porphyrin-appended dendrimers by means of excitation intensity dependent transient absorption measurements. We report singlet-singlet annihilation on two distinct time scales of 18 +/- 5 ps and 130 +/- 10 ps in the dimer and the dendrimers. The... |
16853903 | Selective effect of guest molecule length and hydrogen bonding on the supramolecular host structure. | A host supramolecular structure consisting of bis-(2,2':6',2' '-terpyridine)-4'-oxyhexadecane (BT-O-C16) is shown to respond to guest molecules in dramatic ways, as observed by using scanning tunneling microscopy (STM) on a highly oriented pyrolytic graphite surface under ambient conditions. It is observed that small l... |
16853965 | Novel multilamellar mesostructured molybdenum oxide nanofibers and nanobelts: synthesis and characterization. | One-dimensional molybdenum oxide nanostructures with layered mesostructures were prepared directly from commercial bulk MoO3 crystals by a surfactant-templated hydrothermal process. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, infrared spectra, and thermal analyses have been used t... |
16853933 | Aromatic molecules in restricted geometries: photophysics of naphthalene included in a cyclodextrin functionalized layered solid. | The galleries of an Mg-Al layered double hydroxide have been functionalized by intercalation of carboxymethyl beta-cyclodextrin cavities. The anchored cavities form a random array of identical-sized hydrophobic nanopockets arranged in a bilayer fashion in the interlamellar space of the layered solid. Naphthalene molecu... |
16496669 | [Preparation of ondansetron hydrochloride osmotic pump tablets and their in vitro drug release]. | <h4>Aim</h4>To prepare ondansetron hydrochloride osmotic pump tablets (OND-OPT) and investigate their in vitro drug release behavior.<h4>Methods</h4>OND-OPT were prepared with a single punch press and pan coating technique. Osmotic active agents and plasticizer of coating film were chosen by drug release tests. The eff... |
16489258 | The imbalance between metalloproteinases and their tissue inhibitors is involved in the pathogenesis of dermatitis herpetiformis. | Dermatitis herpetiformis (DH) is a subepidermal autoimmune disease characterized by skin and intestinal lesions consistent with coeliac disease. There are also some data that metalloproteinases (MMPs) are involved in the development of skin lesions in DH, however their exact role in this process is not fully understood... |
16485479 | Intergenogroup recombination in sapoviruses. | Sapovirus, a member of the family Caliciviridae, is an etiologic agent of gastroenteritis in humans and pigs. Analyses of the complete genome sequences led us to identify the first sapovirus intergenogroup recombinant strain. Phylogenetic analysis of the nonstructural region (i.e., genome start to capsid start) grouped... |
16467913 | Nanomedicine and protein misfolding diseases. | Misfolding and self assembly of proteins in nano-aggregates of different sizes and morphologies (nano-ensembles, primarily nanofilaments and nano-rings) is a complex phenomenon that can be facilitated, impeded, or prevented, by interactions with various intracellular metabolites, intracellular nanomachines controlling ... |
16437716 | Colon-specific drug delivery systems based on cyclodextrin prodrugs: in vivo evaluation of 5-aminosalicylic acid from its cyclodextrin conjugates. | <h4>Aim</h4>To investigate the release of cyclodextrin-5-aminosalicylic acid (CyD-5-ASA) in cecum and colon.<h4>Methods</h4>An anti-inflammatory drug 5-ASA was conjugated onto the hydroxyl groups of alpha-, beta- and gamma-cyclodextrins (CyDs) through an ester linkage, and the in vivo drug release behavior of these pro... |
16437659 | Prevalence of Helicobacter pylori infection and intestinal metaplasia in subjects who had undergone surgery for gastric adenocarcinoma in Northwest Italy. | <h4>Aim</h4>To investigate the seroprevalence of Helicobacter pylori (H pylori) infection and its more virulent strains as well as the correlation with the histologic features among patients who had undergone surgery for gastric cancer (GC).<h4>Methods</h4>Samples from 317 (184 males, 133 females, mean age 69+/-3.4 yea... |
16430150 | Complexes of carbon nanotubes with selected carotenoids. | As proven by the UV-VIS, micro-Raman spectroscopies, differential scanning calorimetry, beta-carotene, lycopene, retinoic acid, and retinol adsorbed on the surface of single-walled carbon nanotubes (SWCNT) form electron donor-acceptor (EDA) complexes. The rate of the adsorption of carotenoids is estimated as the rate o... |
16430138 | Nanoscale biomimetics: fabrication and optimization of stability of peptide-based thin films. | The method of thin film preparation known as layer-by-layer assembly is of growing interest for current and envisioned developments in bionanotechnology. Here, cysteine-containing 32mer peptides have been designed, synthesized, purified, and used to prepare polypeptide films. A range of methods-quartz crystal microbala... |
16430133 | Single molecule fluorescence control for nanotechnology. | Nanoscience and nanotechnology are providing fresh approaches to engineer materials with practical applications such as molecular-sized therapeutic and diagnostic devices, drug delivery vehicles, environmental sensors, high-rate manufacturing platforms, and self-assembling nanomachines. In many cases, researchers are m... |
16430131 | RNA nanotechnology: engineering, assembly and applications in detection, gene delivery and therapy. | Biological macromolecules including DNA, RNA, and proteins, have intrinsic features that make them potential building blocks for the bottom-up fabrication of nanodevices. RNA is unique in nanoscale fabrication due to its amazing diversity of function and structure. RNA molecules can be designed and manipulated with a l... |
16414112 | Expression of HBcAg mutant with long internal deletion in Saccharomyces cerevisiae and observation of its self-assembly particles by atomic force microscopy (AFM). | An internally truncated C gene of adr hepatitis B virus core antigen with long internal deletion (aa81-aa116) (DeltaHBcAg with 36aa truncation) was expressed in Saccharomyces cerevisiae and the products (DeltarHBcAg) were purified from a crude lysate of the yeast by three steps: Sephrose CL-4B chromatography, sucrose s... |
16405180 | The study of enantioseparation of zolmitriptan on vancomycin-bonded chiral stationary phase. | In this study, the chiral stationary phase was prepared by bonding vancomycin to 5 microm spherical silica gel according to "one-pot" synthetic strategies, and used to separate the enantiomers of zolmitriptan under polar ionic mode. The influences of mobile phase composition, such as the concentration and ratio of glac... |
16405179 | High operationally stable sol-gel diglycidyloxycalix[4]arene fiber for solid-phase microextraction of propranolol in human urine. | A simple, sensitive, and accurate method for the determination of propranolol in human urine has been developed based on solid-phase microextraction (SPME) followed by GC-flame ionization detection (FID). The sol-gel 5,11,17,23-tetra-tert-butyl-25,27-dihydroxy-26,28-diglycidyloxycalix[4]arene/hydroxy-terminated silicon... |
16396564 | Experimental and theoretical study of the adsorption of fumaramide [2]rotaxane on Au(111) and Ag(111) surfaces. | Thin films of fumaramide [2]rotaxane, a mechanically interlocked molecule composed of a macrocycle and a thread in a "bead and thread" configuration, were prepared by vapor deposition on both Ag(111) and Au(111) substrates. X-ray photoelectron spectroscopy (XPS) and high-resolution electron-energy-loss spectroscopy wer... |
16392947 | Coarse-grained molecular-dynamics simulations of the self-assembly of pentablock copolymers into micelles. | Multiblock polymers in aqueous solution, where one or several blocks are hydrophobic, exhibit a rich variety of phases and states of aggregation. In this paper, we investigate a pentablock system ABCBA, where the B block is always hydrophilic and the A and C blocks have varying degrees of hydrophobicity depending on ex... |
16392906 | Mega three-photon absorption cross-section enhancement in pseudoisocyanine J-aggregates. | Herein we report an extraordinary three-photon absorption cross-section (sigma'3) enhancement in J-aggregates supramolecular systems. The much higher value of sigma'3 in PIC J-aggregate (2.5 x 10(-71) cm6 s2 ph(-2)) compared to typical values obtained in organic molecules (10(-80) cm6 s2 ph(-2)) is attributed to the st... |
16375456 | Probing the sequence of conformationally induced polarity changes in the molecular chaperonin GroEL with fluorescence spectroscopy. | Hydrophobic interactions play a major role in binding non-native substrate proteins in the central cavity of the bacterial chaperonin GroEL. The sequence of local conformational changes by which GroEL and its cofactor GroES assist protein folding can be explored using the polarity-sensitive fluorescence probe Nile Red.... |
16366618 | Charge transfer processes in conjugated triarylamine-oligothiophene-perylenemonoimide dendrimers. | The synthesis and charge transfer properties of triarylamine-oligothiophene-perylenemonoimide dendrimers, TPA(T2-PMI)3 and TPA(T4-PMI)3, are described. The fluorescence quantum yields indicate strong emission quenching by electron transfer [phi(THF) = 0.004 for TPA(T2-PMI)3, phi(THF) = 0.003 for TPA(T4-PMI)3, and phi(T... |
16366594 | Charge dependence of cellular uptake and selective antitumor activity of porphyrazines. | Porphyrazines (pzs), or tetraazaporphyrins, can be viewed as porphyrinic macrocycles in which the porphyrin meso (CH) groups are replaced by nitrogen atoms; as such, it can be anticipated that pzs would show similar biocompatibility and biodistribution to those of porphyrins. However, distinctive chemical and physical ... |
16366591 | Human P2Y(6) receptor: molecular modeling leads to the rational design of a novel agonist based on a unique conformational preference. | Combining molecular dynamics (MD) in a hydrated phospholipid (DOPC) bilayer, a Monte Carlo search, and synthesis of locked nucleotide analogues, we discovered that the Southern conformation of the ribose is preferred for ligand recognition by the P2Y(6) receptor. 2'-Deoxy-(S)-methanocarbaUDP was found to be a full agon... |
16366590 | Semi-rational design of (north)-methanocarba nucleosides as dual acting A(1) and A(3) adenosine receptor agonists: novel prototypes for cardioprotection. | Ring-constrained adenosine analogues have been designed to act as dual agonists at tissue-protective A(1) and A(3) adenosine receptors (ARs). 9-Ribosides transformed into the ring-constrained (N)-methanocarba-2-chloro-5'-uronamides consistently lost affinity at A(1)/A(2A)ARs and gained at A(3)AR. Among 9-riboside deriv... |
16366573 | Utilization of a combination of weak hydrogen-bonding interactions and phase segregation to yield highly thermosensitive supramolecular polymers. | Supramolecular polymerization, i.e., the self-assembly of polymer-like materials through the utilization of the noncovalent bond, is a developing area of research. In this paper, we report the synthesis and investigation of nucleobase-terminated (N6-anisoyl-adenine and N4-(4-tert-butylbenzoyl)cytosine) low molecular we... |
16366540 | The inverted cucurbit[n]uril family. | We report the isolation, characterization, and recognition behavior of iCB[6] and iCB[7], which are diastereomers of CB[6] and CB[7], respectively, containing a single inverted glycoluril unit. Product resubmission experiments establish that these inverted CB[n] are intermediates in the mechanism of CB[n] formation. As... |
16366537 | A chiral luminescent Au16 ring self-assembled from achiral components. | A luminescent supramolecular chiral Au16 ring with 4.822 nm perimeter that self-assembled from a tetrameric array of achiral Au2 units is described. Intra- and intermolecular Au...Au interactions play an important role in directing its chiral self-assembly. |
16363804 | Peptergents: peptide detergents that improve stability and functionality of a membrane protein, glycerol-3-phosphate dehydrogenase. | Toward enhancing in vitro membrane protein studies, we have utilized small self-assembling peptides with detergent properties ("peptergents") to extract and stabilize the integral membrane flavoenzyme, glycerol-3-phosphate dehydrogenase (GlpD), and the soluble redox flavoenzyme, NADH peroxidase (Npx). GlpD is a six tra... |
16353263 | Functional liquid-crystalline assemblies: self-organized soft materials. | In the 21st century, soft materials will become more important as functional materials because of their dynamic nature. Although soft materials are not as highly durable as hard materials, such as metals, ceramics, and engineering plastics, they can respond well to stimuli and the environment. The introduction of order... |
16331974 | Spatially and temporally controlled biomineralization is facilitated by interaction between self-assembled dentin matrix protein 1 and calcium phosphate nuclei in solution. | Bone and dentin biomineralization are well-regulated processes mediated by extracellular matrix proteins. It is widely believed that specific matrix proteins in these tissues modulate nucleation of apatite nanoparticles and their growth into micrometer-sized crystals via molecular recognition at the protein-mineral int... |
16390817 | Rectal and vaginal administration of insulin-chitosan formulations: an experimental study in rabbits. | Insulin is a polypeptide drug and it is degraded by gastrointestinal enzymes, therefore, it cannot be used via oral route readily. There are only parenteral forms available in the market. The aim of this study was to investigate the effect of rectal and vaginal administration of various insulin gel formulations on the ... |
16391741 | Dendritic effects on the ordered assembly and the interfacial one-electron oxidation of redox-active dendron-functionalized gold nanoparticles. | A higher generation dendron with a long-alkyl chain thiol (DA2-SH) induced the formation of nanoparticles with a small core with quite a narrow size distribution (1.5 +/- 0.1 nm), the self-assembly of one-dimensional arrays of these gold nanoparticles (DA2-Au), and the stabilization for the formation of the radical cat... |
16363856 | Tetra-2,3-pyrazinoporphyrazines with externally appended pyridine rings. 3. A new highly electron-deficient octacationic macrocycle: tetrakis-2,3-[5,6-di{2-(N-methyl)pyridiniumyl}pyrazino]porphyrazine, [(2-Mepy)8TPyzPzH(2)]8+. | A new octacationic macrocycle, tetrakis-2,3-[5,6-di{2-(N-methyl)pyridiniumyl}pyrazino]porphyrazine, was obtained in its hydrated form as the water-soluble iodide salt. This compound, abbreviated as [(2-Mepy)(8)TPyzPzH(2)](I(8)).8H(2)O (2-Mepy = 2(N-methyl)pyridiniumyl moiety), was obtained by demetalation of the corres... |
16363852 | A kinetically controlled trans bifunctionalized organoimido derivative of the Lindqvist-type hexamolybdate: synthesis, spectroscopic characterization, and crystal structure of (n-Bu4N)2{trans-[Mo6O17(NAr)2]} (Ar = 2,6-dimethylphenyl). | A kinetically controlled trans bifunctionalized organoimido derivative of hexamolybdate, (n-Bu(4)N)(2){trans-[Mo(6)O(17)(NAr)(2)]} (Ar = 2,6-dimethylphenyl) 1, in which the two 2,6-dimethylphenylimido groups are bonded to hexamolybdate at the trans positions, has been successfully synthesized in ca. 60% yield under mil... |
16363843 | X-ray diffraction and EXAFS studies of hydroxo-Cu(II) complexes based on a calix[6]arene-N3 ligand: evidence for a mononuclear-dinuclear equilibrium controlled by supramolecular features. | The formation of hydroxo complexes based on a calix[6]trisimidazole ligand is described. Deprotonation of the mononuclear Cu(II)-aqua complex gives rise to a dinuclear bis(mu-hydroxo) complex that has been characterized by X-ray diffraction analysis. Spectroscopic studies (EPR and UV-vis), conducted in dichloromethane ... |
16363825 | Reduction of the host cationic framework charge by isoelectronic substitution: synthesis and structure of Hg7Ag2P8X6 (X = Br, I) and Hg6Ag4P8Br6. | The first compounds, Hg(7)Ag(2)P(8)X(6) (X = Br, I) and Hg(6)Ag(4)P(8)Br(6), featuring the partial isoelectronic substitution of Hg(2+) for Ag(1+) in mercury-pnicogen frameworks have been obtained and structurally characterized. The new compounds are the supramolecular assemblies built of the covalently bonded metal-pn... |
16386185 | [Study of continuous blood purification in severe pneumonia patients with multiple organ failure]. | <h4>Objective</h4>To review retrospectively the effect of continuous blood purification (CBP) on septic shock with acute renal failure and respiratory failure as a result of severe pneumonia, and to analyze its relationship with prognosis.<h4>Methods</h4>Twenty-five patients diagnosed as severe pneumonia with varying d... |
16386180 | [Study on changes in inflammatory cytokines and the relationship to multiple organ injury in rats with aspiration lung injury after fire-arm injury]. | <h4>Objective</h4>To observe the phasic variations in concentrations of pro-inflammatory and anti-inflammatory cytokines, and to explore their potential roles in the occurrence and development process of multiple organ dysfunction.<h4>Methods</h4>Fire-arm induced aspiration lung injury model was replicated. The followi... |
16359705 | Fold independent structural comparisons of protein-ligand binding sites for exploring functional relationships. | The rapid growth in protein structural data and the emergence of structural genomics projects have increased the need for automatic structure analysis and tools for function prediction. Small molecule recognition is critical to the function of many proteins; therefore, determination of ligand binding site similarity is... |
16365166 | Expression of mutant huntingtin in glial cells contributes to neuronal excitotoxicity. | Huntington disease (HD) is characterized by the preferential loss of striatal medium-sized spiny neurons (MSNs) in the brain. Because MSNs receive abundant glutamatergic input, their vulnerability to excitotoxicity may be largely influenced by the capacity of glial cells to remove extracellular glutamate. However, litt... |
16363857 | Tetra-2,3-pyrazinoporphyrazines with externally appended pyridine rings. 4. UV-visible spectral and electrochemical evidence of the remarkable electron-deficient properties of the new tetrakis-2,3-[5,6-di{2-(N-methyl)pyridiniumyl}pyrazino]porphyrazinatometal octacations, [(2-Mepy)8TPyzPzM]8+ (M = MgII(H2O), CoII, CuII,... | Metal derivatives of the octacationic tetrakis-2,3-[5,6-di{2-(N-methyl)pyridiniumyl}pyrazino]porphyrazine macrocycle [(2-Mepy)(8)TPyzPzH(2)](8+) (2-Mepy = 2-(N-methyl)pyridiniumyl ring) isolated as water-soluble hydrated iodide salts of the general formula [(2-Mepy)(8)TPyzPzM](I(8)).xH(2)O, (M = Mg(II)(H(2)O), Co(II), ... |
16363853 | Synthesis, characterization, and luminescence properties of a new series of Eu3+-containing macrocycles. | The synthesis and structural characterization of a series of neutral Eu(3+)-containing macrocyclic complexes, Eu(4)-Eu(7), are reported. The synthetic pathway herein allows for the size and functionality of the macrocycle to be tailored in one step from a common precursor (N,N' '-bis(p-isothiocyanatobenzylcarbamoylmeth... |
16382961 | Effect of hydroxypropyl-beta-cyclodextrin on the degradation of pentachlorophenol by potassium monopersulfate catalyzed with iron(III)-porphyrin complex. | A novel biomimetic catalytic system containing a supramolecular complex between iron(III)-tetrakis(p-sulfonatophenyl)porphyrin [Fe(III)-TPPS] and hydroxypropyl-beta-cyclodextrin (HP-beta-CD) was examined for the potassium monopersulfate catalyzed oxidation of pentachlorophenol (PCP). In the absence of HP-beta-CD, the p... |
16382919 | Molecular structure in soil humic substances: the new view. | A critical examination of published data obtained primarily from recent nuclear magnetic resonance spectroscopy, X-ray absorption near-edge structure spectroscopy, electrospray ionization-mass spectrometry, and pyrolysis studies reveals an evolving new view of the molecular structure of soil humic substances. According... |
16351191 | Nanotechnology-based photodynamic therapy for neovascular disease using a supramolecular nanocarrier loaded with a dendritic photosensitizer. | Photodynamic therapy (PDT) for exudative age-related macular degeneration (AMD) was evaluated using a supramolecular nanomedical device, that is, a novel dendritic photosensitizer (DP) encapsulated by a polymeric micelle formulation. The characteristic dendritic structure of the DP prevents aggregation of its core sens... |
16351097 | Synthesis of chiral self-assembling rhombs and their characterization in solution, in the gas phase, and at the liquid-solid interface. | Chiral, enantiopure metallo-supramolecular rhombs self-assemble in solution through coordination of bis-pyridyl-substituted ligands with (en)M(NO3)2 (en = ethylenediamine, M = Pd(II), Pt(II)). Characterization by NMR and CD spectroscopy in solution and by ESI-FT-ICR mass spectrometry in the gas phase suggests that an e... |
16380427 | The evolutionary history of Cys-tRNACys formation. | The recent discovery of an alternate pathway for indirectly charging tRNA(Cys) has stimulated a re-examination of the evolutionary history of Cys-tRNA(Cys) formation. In the first step of the pathway, O-phosphoseryl-tRNA synthetase charges tRNA(Cys) with O-phosphoserine (Sep), a precursor of the cognate amino acid. In ... |
16380426 | Enhancer-independent Mu transposition from two topologically distinct synapses. | Transposition of Mu is strictly dependent on a specific orientation of the left (L) and right (R) ends of Mu and a distant enhancer site (E) located on supercoiled DNA. Five DNA crossings are trapped in the three-site synapse, two of which are contributed by the interwrapping of L and R. To determine the contribution o... |
16375759 | Synthetic approaches to the 2004 new drugs. | New drugs are introduced to the market every year and each individual drug represents a privileged structure for its biological target. In addition, these new chemical entities (NCEs) not only provide insights into molecular recognition, but also serve as leads for designing future drugs. To this end, this review cover... |
16375426 | Self-assembly of gold nanoparticles induced by poly(oxypropylene)diamines. | A series of poly(oxypropylene)diamines D230, D400, D2000, and D4000, having molecular weights of hydrophobic segments of 230, 400, 2000, and 4000, were used as ligands to synthesize self-organized gold nanocrystals. Ligand exchange significantly reduced the average particle size and the polydispersity of nanocrystals, ... |
16375418 | Architecture of a biocompatible supramolecular material by supersaturation-driven fabrication of its fiber network. | The architecture of a biocompatible organogel formed by gelation of a small molecule organic gelator, N-lauroyl-L-glutamic acid di-n-butylamide, in isostearyl alcohol was investigated based on a supersaturation-driven crystallographic mismatch branching mechanism. By controlling the supersaturation of the system, the c... |
16375366 | High conversion synthesis of pyrene end functionalized polyrotaxane based on poly(ethylene oxide) and alpha-cyclodextrins. | We describe the quantitative synthesis of new pyrene labeled cyclodextrin-based polyrotaxane starting from pseudopolyrotaxane of alpha,omega-dimethacrylate poly(ethylene oxide) (PEO) and alpha-cyclodextrins (alpha-CDs). Using a solvent mixture (H2O/dimethyl sulfoxide (DMSO)), an almost quantitative conversion in polyro... |
16375355 | Spectrophotometric study of fluorescence sensing and selective binding of biochemical substrates by 2,2'-bridged bis(beta-cyclodextrin) and its water-soluble fullerene conjugate. | A bis(beta-cyclodextrin)-fullerene conjugate (3) linked at the secondary hydroxyl side was prepared in a good yield from its precursor N,N'-bis(2-(2-aminoethylamino)ethyl)malonamide-bridged bis(beta-cyclodextrin) (2). Spectrophotomeric studies on the conformation and the inclusion complexation behavior of 3 with a vari... |
16375334 | MD simulations of the binding of alcohols and diols by a calixarene in water: connections between microscopic and macroscopic properties. | We report results of molecular dynamics (MD) simulations of the complexes of p-sulfonatocalix[4]arene with linear alcohols from ethanol to heptanol in water at 25 degrees C. We show that these complexes are of the inclusion type and are governed by van der Waals interactions between the calixarene cavity and the insert... |
16375308 | Study on the formation of the ketonic defects in the thermal degradation of ladder-type poly(p-phenylenes) by vibrational spectroscopy. | We have investigated the thermal degradation in air by Fourier transform infrared spectroscopy of a ladder-type copolymer containing fluorene units in the backbone (Me-LPF), to reveal the formation of the ketonic defects. As thermal treatment of Me-LPF film at 200 degrees C in air proceeds, a new group of complex absor... |
16375304 | Uniform gold nanorod arrays from polyethylenimine-coated alumina templates. | Monolithic Au nanorod arrays can be grown by electrodeposition in Au-backed nanoporous alumina templates using polyethylenimine (PEI) as an adhesion layer, with excellent height control between 300 nm and 1.4 microm. The local height distribution can be extremely narrow with relative standard deviations well below 2%. ... |
16375298 | Chemiluminescence of CdTe nanocrystals induced by direct chemical oxidation and its size-dependent and surfactant-sensitized effect. | CdTe nanocrystals (NCs) capped with thioglycolic acid (TGA) were synthesized via a microwave-assisted method. The chemiluminescence (CL) of CdTe NCs induced by directly chemical oxidation and its size-depended and surfactant-sensitized effect in aqueous solution were then investigated. It was found that oxidants, espec... |
16375485 | NMR probing of structural peculiarities in ionic solutions close to critical point. | (1)H, (23)Na, (35)Cl, (79)Br, and (81)Br NMR chemical shifts (delta) and signal half widths (Delta(12)) have been measured in aqueous electrolyte mixtures [tetrahydrofuran/H(2)ONaCl and 3-methylpyridine (3MP)H(2)ONaBr] at different mass fractions of salt (X) in the one-phase region, close to their lower critical soluti... |
16366565 | A stereoelectronic effect on turn formation due to proline substitution in elastin-mimetic polypeptides. | Stereoelectronic effects have been identified as contributing factors to the conformational stability of collagen-mimetic peptide sequences. To assess the relevance of these factors within other protein structural contexts, three polypeptide sequences were prepared in which the sequences were derived from the canonical... |
16366539 | Metal-organic frameworks with exceptionally high capacity for storage of carbon dioxide at room temperature. | Metal-organic frameworks (MOFs) show high CO2 storage capacity at room temperature. Gravimetric CO2 isotherms for MOF-2, MOF-505, Cu3(BTC)2, MOF-74, IRMOFs-11, -3, -6, and -1, and MOF-177 are reported up to 42 bar. Type I isotherms are found in all cases except for MOFs based on Zn4O(O2C)6 clusters, which reveal a sigm... |
16360032 | Ku70, a component of DNA-dependent protein kinase, is a mammalian receptor for Rickettsia conorii. | Rickettsia conorii, a strictly intracellular and category C priority bacterial pathogen (NIAID), invades different mammalian cells. Although some signaling events involved in bacterial entry have been documented, the bacterial and host proteins mediating entry were not known. We report the identification of the Ku70 su... |
16356061 | New isoreticular metal-organic framework materials for high hydrogen storage capacity. | We propose new isoreticular metal-organic framework (IRMOF) materials to increase the hydrogen storage capacity at room temperature. Based on the potential-energy surface of hydrogen molecules on IRMOF linkers and the interaction energy between hydrogen molecules, we estimate the saturation value of hydrogen sorption c... |
16354059 | Quantum mechanical calculations of conformationally relevant 1H and 13C NMR chemical shifts of calixarene systems. | [graphs: see text] QM GIAO calculations of 13C and 1H chemical shift values of the ArCH2Ar group have been performed, using the hybrid DFT functional MPW1PW91 and the 6-31G(d,p) basis set, on some representative calixarenes and on a series of simplified calixarene models allowing derivation of chemical shift surfaces v... |
16354058 | A fast-moving [2]rotaxane whose stoppers are remote from the copper complex core. | [reaction: see text] A new copper-complexed rotaxane is described. It consists of a two-coordination site ring threaded by a sterically non-hindering 2,2'-bipyridine derivative. An electrochemical signal (oxidation or reduction of the copper center, Cu(I) or Cu(II)) induces rearrangement of the system. By using long an... |
16354918 | Neurosteroid access to the GABAA receptor. | GABAA receptors are a pivotal inhibitory influence in the nervous system, and modulators of the GABAA receptor are important anesthetics, sedatives, anticonvulsants, and anxiolytics. Current views of receptor modulation suggest that many exogenous drugs access and bind to an extracellular receptor domain. Using novel s... |
16351230 | Template-assisted growth of nominally cubic (100)-oriented three-dimensional crack-free photonic crystals. | Three-dimensional (3D) photonic crystals (PhCs) are now beginning to acquire functionality via the use of dopants and heterostructures. However, the self-organized fabrication of large-area single crystals that are free of cracks and stacking faults has remained a challenge. We demonstrate a technology for the fabricat... |
16351220 | Two computational primitives for algorithmic self-assembly: copying and counting. | Copying and counting are useful primitive operations for computation and construction. We have made DNA crystals that copy and crystals that count as they grow. For counting, 16 oligonucleotides assemble into four DNA Wang tiles that subsequently crystallize on a polymeric nucleating scaffold strand, arranging themselv... |
16351213 | Self-assembly of size- and position-controlled ultralong nanodot chains using near-field optical desorption. | We report the self-assembly of a size- and position-controlled ultralong nanodot chain using a novel effect of near-field optical desorption. A sub-100-nm dot chain with a deviation of 5 nm forms at a size based on plasmon resonance, depending on the photon energy; the resulting structure forms a high-transmission-effi... |
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