id stringlengths 4 8 | title stringlengths 1 642 | abstract stringlengths 50 17.9k |
|---|---|---|
12357750 | Urea as 'deus ex machina' in giant molybdenum blue type cluster synthesis: an unusual hybrid compound with perspectives for related nano, supramolecular and extended structures. | The reaction of an aqueous solution of ammonium heptamolybdate with sodium dithionite and urea--a glue and cluster hydration shell destructing agent corresponding to its role in inclusion compound chemistry--at low pH value results in the formation of nanosized ring shaped molybdenum-oxide based clusters which in a sho... |
12357726 | Photoprocesses of photosensitizing drugs within cyclodextrin cavities. | Recently some interest has been focused on the photobehavior of CD-drug inclusion complexes in relation to the problem of the biological photosensitization by drugs. This review is dedicated to the illustration of the mechanistic aspects of the photoprocesses occurring in some non-steroidal anti-inflammatory drugs (NSA... |
12357725 | Methods of modulating hydrogen bonded interactions in synthetic host-guest systems. | Hydrogen bonded interactions are among the most important non-covalent interactions in supramolecular chemistry. The strength, selectivity and directionality inherent in hydrogen bonding processes have allowed the creation of complex and efficient molecular hosts capable of selective binding to a wide variety of comple... |
12358434 | Pokeweed antiviral protein binds to the cap structure of eukaryotic mRNA and depurinates the mRNA downstream of the cap. | Several cap-binding proteins from both the nucleus and cytosol have been identified that mediate processes such as pre-mRNA splicing, translation initiation, and mRNA turnover. Here we describe a novel cap-binding protein, pokeweed antiviral protein (PAP), a 29-kDa type I ribosome-inactivating protein (RIP) isolated fr... |
12356872 | P21-activated kinase 4 interacts with integrin alpha v beta 5 and regulates alpha v beta 5-mediated cell migration. | p21-activated kinase 1 (PAK1) can affect cell migration (Price et al., 1998; del Pozo et al., 2000) and modulate myosin light chain kinase and LIM kinase, which are components of the cellular motility machinery (Edwards, D.C., L.C. Sanders, G.M. Bokoch, and G.N. Gill. 1999. Nature Cell Biol. 1:253-259; Sanders, L.C., F... |
12356870 | T cell receptor ligation induces the formation of dynamically regulated signaling assemblies. | Tcell antigen receptor (TCR) ligation initiates tyrosine kinase activation, signaling complex assembly, and immune synapse formation. Here, we studied the kinetics and mechanics of signaling complex formation in live Jurkat leukemic T cells using signaling proteins fluorescently tagged with variants of enhanced GFP (EG... |
12356867 | A combination of three distinct trafficking signals mediates axonal targeting and presynaptic clustering of GAD65. | The signals involved in axonal trafficking and presynaptic clustering are poorly defined. Here we show that targeting of the gamma-aminobutyric acid-synthesizing enzyme glutamate decarboxylase 65 (GAD65) to presynaptic clusters is mediated by its palmitoylated 60-aa NH(2)-terminal domain and that this region can target... |
12356270 | Water structure theory and some implications for drug design. | The development of theories of water structure has been hindered in the past by the difficulty of experimental measurement. Both measurement and computer modelling studies have now reached the stage where theoretical treatments of water structure are converging to a broadly acceptable model. In current understanding, w... |
12353923 | Superoxide dismutase mimetics with catalase activity reduce the organ injury in hemorrhagic shock. | Reactive oxygen species (ROS) contribute to the multiple organ failure (MOF) in hemorrhagic shock. Here we investigate the effects of two superoxide dismutase (SOD) mimetics with catalase activity (EUK-8 and EUK-134) on the circulatory failure and the organ injury and dysfunction associated with hemorrhagic shock in th... |
12350249 | Gustatory sensilla sensitive to protein kairomones trigger host acceptance by an endoparasitoid. | Proteins isolated from the host cocoon of Acrolepiopsis assectella (Lepidoptera: Yponomeutoidea) act as kairomones for host acceptance by the endoparasitoid wasp Diadromus pulchellus Wesmael (Hymenoptera: Ichneumonidae). In this study, morphological, ultrastructural and electrophysiological studies were carried out in ... |
12352988 | Self-organization of supramolecular helical dendrimers into complex electronic materials. | The discovery of electrically conducting organic crystals and polymers has widened the range of potential optoelectronic materials, provided these exhibit sufficiently high charge carrier mobilities and are easy to make and process. Organic single crystals have high charge carrier mobilities but are usually impractical... |
12350146 | Three novel cytochalasins X, Y, and Z from Pseudeurotium zonatum. | Fermentation of Pseudeurotium zonatum led to the isolation of the known cytochalasin G (1) and three new cytochalasins, X, Y, and Z (2-4). These four compounds are the only naturally occurring cytochalasins reported to date that contain an indole-substituted perhydroisoindol-1-one fused with an 11-membered macrocycle. |
12352031 | Multiple organ failure in patients with cardiogenic shock is associated with high plasma levels of interleukin-6. | <h4>Objective</h4>In patients with septic shock, multiple organ failure (MOF) is associated with high levels of interleukin-6 (IL-6). Although organ failure is also a common complication of cardiogenic shock (CS), IL-6 levels have been reported to be lower in patients with CS than in patients with septic shock. We stud... |
12350123 | Enantioseparation of phenothiazines in cyclodextrin-modified micellar electrokinetic chromatography. | In this study, enantioseparations of five phenothiazines in cyclodextrin (CD)-modified micellar electrokinetic chromatography (MEKC) were investigated using a citrate buffer containing tetradecyltrimethylammonium bromide (TTAB) as a cationic surfactant at low pH. Beta-cyclodextrin (beta-CD) and hydroxylpropyl-beta-CD (... |
12350118 | Polyrotaxane approach for synthesis of continuous beds for capillary electrochromatography. | The polyrotaxane formation approach was evaluated for synthesis of continuous beds for capillary electrochromatography. This approach has the advantage of generating diverse electroosmotic and chromatographic properties without chemical reactions. The polyrotaxane derivatized continuous beds were formed adding the macr... |
12349901 | Sensitivity of hybrid ovine/rat GH receptors to oGH and rat GH in transfected FDC-P1 mouse myeloid cells in vitro. | We have described previously the properties of two mutant ovine growth hormone receptor extracellular domain (oGHR-ECD) proteins which were created by substituting sequences from the rat GHR at two different locations within the framework of the oGHR-ECD. The first mutation occurred at a region close to the N-terminus ... |
12298024 | Construction and probing of multisite chiral catalysts: dendrimer fixation of c2-symmetrical diphosphinerhodium complexes. | A series of chiral phosphine-functionalized poly(propyleneimine) (PPI) dendrimers was synthesized by the reaction of carboxyl-linked C(2)-chiral pyrphos ligand (pyrphos=3,4-bis(diphenylphosphino)pyrrolidine) with zeroth-fourth generation PPI using ethyl-N,N-dimethylaminopropylcarbodiimide (EDC)/1-hydroxybenzotriazol as... |
12298007 | Synthesis and self-assembly of 2,9,16-tri(tert-butyl)-23-(10-mercaptodecyloxy)phthalocyanine and the application of its self-assembled monolayers in organic light-emitting diodes. | 2,9,16-Tri(tert-butyl)-23-(10-mercaptodecyloxy)phthalocyanine (8) and its disulfide (9) have been synthesized and characterized, and their self-assembling behaviors on gold substrates have been studied. Characteristic Q-bands were observed at about 630 nm in the UV/visible spectra of the self-assembling monolayers (SAM... |
12271698 | X-ray structure of the delta-cyclodextrin complex with cycloundecanone. | The crystal structure of the delta-cyclodextrin complex with cycloundecanone shows a channel-type structure consisting of head-to-head dimer units that include four guest molecules. |
12271654 | Photoluminescent supramolecular polymers: metal-ion directed polymerization of terpyridine-functionalized perylene bisimide dyes. | Perylene bisimide dyes bearing one and two 2,2':6',2"-terpyridine receptor groups were prepared and the structural and optical properties of their Zn2+ complexes were investigated by 1H NMR and fluorescence experiments. |
12271647 | Phosphorus-containing dendrimers bearing galactosylceramide analogs: self-assembly properties. | We report the synthesis and the supramolecular auto-assembly of catanionic phosphorus-containing dendrimers mimicking multisite analogs of galactosylceramide. |
12271630 | Supramolecular synthons based on N-H...N and C-H...O hydrogen bonds. Crystal engineering of a helical structure with 5,5-diethylbarbituric acid. | 5,5-Diethylbarbituric acid is a convenient molecular precursor for a newly identified N-H...N/C-H...O synthon, which is robust enough for the design of a helix architecture. |
12271629 | Control of the stoichiometry in host-guest complexation by redox chemistry of guests: inclusion of methylviologen in cucurbit[8]uril. | The binding stoichiometry of a host-guest complex can be effectively controlled by the redox chemistry of the guest: a 1:1 inclusion complex of methylviologen dication (MV2+) in cucurbit[8]uril (CB[8]) converts completely and reversibly to a 2:1 inclusion complex of cation radical (MV+.) in CB[8] upon the reduction of ... |
12242224 | A mutation in the ATP2 gene abrogates the age asymmetry between mother and daughter cells of the yeast Saccharomyces cerevisiae. | The yeast Saccharomyces cerevisiae reproduces by asymmetric cell division, or budding. In each cell division, the daughter cell is usually smaller and younger than the mother cell, as defined by the number of divisions it can potentially complete before it dies. Although individual yeast cells have a limited life span,... |
12238926 | Structural determinants of A(3) adenosine receptor activation: nucleoside ligands at the agonist/antagonist boundary. | Mutagenesis of the human A(3) adenosine receptor (AR) suggested that certain amino acid residues contributed differently to ligand binding and activation processes. Here we demonstrated that various adenosine modifications, including adenine substitution and ribose ring constraints, also contributed differentially to t... |
12236754 | Steric control of organic transformation by a dendrimer cage: organocobalt dendrimer porphyrins as novel coenzyme B(12) mimics. | Cobalt(II) complexes of poly(aryl ester) dendrimer porphyrins (m-[Gn]TPP)Co(II) and (p-[Gn]TPP)Co(II) (n = 0-3) underwent AIBN-initiated alkylation (AIBN = 2,2'-azobis(isobutyronitrile)) at the metal center with propargyl alcohol in CDCl(3) at 60 degrees C, where the dendritic substituents did not affect the overall co... |
12236738 | Remarkable stability and enhanced optical activity of a chiral supramolecular bis-porphyrin tweezer in both solution and solid state. | Interaction of the achiral syn (face-to-face) conformer of the ethane-bridged bis(zinc octaethylporphyrin) with the enantiopure 1,2-diaminocyclohexane results in the exclusive formation of a supramolecular chiral tweezer. This 1:1 host-guest complex exhibits remarkable stability in both solution (even upon photoexcitat... |
12236734 | Synthesis, structure, and ferromagnetic behavior of decacopper(II) cluster complex supported by hexaanionic p-tert-butylthiacalix[6]arene. | A nanosized decacopper(II) cluster complex was synthesized using p-tert-butylthiacalix[6]arene as a ligand. In the complex, the calixarene assumes a "pinched cone" conformation and acts as an undecadentate ligand via six phenoxy oxygen and five sulfur atoms. The resulting pentacopper(II) subunits are connected by two h... |
12236711 | Anion-anion assembly: a new class of anionic supramolecular polymer containing 3,4-dichloro-2,5-diamido-substituted pyrrole anion dimers. | Two molecules containing two 2,5-diamido,3,4-dichloropyrrole units linked via 1,3- or 1,4-substituted benzene rings have been synthesized. The pyrrole groups in these compounds deprotonate in the presence of tetrabutylammonium fluoride and form pyrrole anion dimers via NH...N- hydrogen bonds. This dimerization process ... |
12237555 | Cyclodextrin-mediated deacylation of amino acid esters with marked stereoselectivity. | With respect to the hydrolysis (deacylation) of Z-D(L)-amino acid esters (N-(benzyloxycarbonyl)-D(L)-amino acid p-nitrophenyl esters) mediated by alpha-, beta- and gamma-cyclodextrins (CyDs), a remarkably high enantioselectivity (L/D=9.0) was observed for the deacylation of Ala substrate with gamma-CyD. The kinetic res... |
12236792 | Functionalized congeners of tyrosine-based P2X(7) receptor antagonists: probing multiple sites for linking and dimerization. | Chemically funtionalized analogues of antagonists of the P2X(7) receptor, an ATP-gated cation channel, were synthesized as tools for biophysical studies of the receptor. These functionalized congeners were intended for use in chemical conjugation with retention of biological potency. The antagonists were L-tyrosine der... |
12237130 | Enzymatic synthesis and characterization of oligosaccharides structurally related to the repeating unit of Pullulan. | A trisaccharide (Glcalpha1-4Glcalpha1-6Glc) and a tetrasaccharide (Glcalpha1-4Glcalpha1-4Glcalpha1-6Glc) the structures of which are related to that of repeating unit of pullulan have been obtained, exploiting the transglycolytic activity of Aspergillus niger cyclodextrin glucanotransferase. Both products were obtained... |
12236351 | Metal complexation of thiacrown ether macrocycles by electrospray ionization mass spectrometry. | In the present study, electrospray ionization mass spectrometry is used to evaluate the metal-binding selectivities of an array of novel caged macrocycles for mercury(II), lead(II), cadmium(II), and zinc(II) ions. In homogeneous methanol/chloroform solutions as well as extractions of metals from aqueous solution by mac... |
12235394 | Binding affinity of Escherichia coli RNA polymerase*sigma54 holoenzyme for the glnAp2, nifH and nifL promoters. | Escherichia coli RNA polymerase associated with the sigma54 factor (RNAP*sigma54) is a holoenzyme form that transcribes a special class of promoters not recognized by the standard RNA polymerase*sigma70 com plex. Promoters for RNAP*sigma54 vary in their overall 'strength' and show differences in their response to the p... |
12235377 | Interaction of the ocr gene 0.3 protein of bacteriophage T7 with EcoKI restriction/modification enzyme. | The ocr protein, the product of gene 0.3 of bacteriophage T7, is a structural mimic of the phosphate backbone of B-form DNA. In total it mimics 22 phosphate groups over approximately 24 bp of DNA. This mimicry allows it to block DNA binding by type I DNA restriction enzymes and to inhibit these enzymes. We have determi... |
12235170 | Uptake of long-chain fatty acids in HepG2 cells involves caveolae: analysis of a novel pathway. | We investigated the role of caveolae in uptake and intracellular trafficking of long chain fatty acids (LCFA) in HepG2 human hepatoma cells. The uptake of [(3)H]oleic acid and [(3)H]stearic acid into HepG2 cells was measured by radioactive assays and internalization of the non-metabolizable fluorescent fatty acid 12-(N... |
12235215 | Inhibition of type 1 cytokine-mediated inflammation by a soluble CD30 homologue encoded by ectromelia (mousepox) virus. | CD30 is up-regulated in several human diseases and viral infections but its role in immune regulation is poorly understood. Here, we report the expression of a functional soluble CD30 homologue, viral CD30 (vCD30), encoded by ectromelia (mousepox) virus, a poxvirus that causes a severe disease related to human smallpox... |
12234917 | The structure of bacterial DnaA: implications for general mechanisms underlying DNA replication initiation. | The initiation of DNA replication is a key event in the cell cycle of all organisms. In bacteria, replication initiation occurs at specific origin sequences that are recognized and processed by an oligomeric complex of the initiator protein DnaA. We have determined the structure of the conserved core of the Aquifex aeo... |
12234211 | Real-time electrochemical monitoring: toward green analytical chemistry. | This Account presents a survey of recent advances in electrochemical sensing technology relevant to green analytical chemistry and examines the potential advantages, limitations, and applications of these monitoring devices. Stricter environmental control and effective process monitoring have created considerable deman... |
12230399 | Diastereoisomeric singly bridged cyclophosphazene-macrocyclic compounds. | 31P NMR spectroscopy and added chiral shift reagent (CSR) or chiral solvating agent (CSA) have been used to show that unsymmetrically substituted singly bridged macrocyclic phosphazene compounds exist as 1:1 diastereoisomers of two racemic mixtures, in contrast to previous work (ref 2) on symmetrically substituted dias... |
12230395 | [Ag(2)(C(33)H(26)N(2)O(2))(H(2)O)(2)(SO(3)CF(3))(2)].0.5C(6)H(6): a luminescent supramolecular silver(I) complex based on metal-carbon and metal-heteroatom interactions. | A novel fulvene-type bidentate ligand 1 has been synthesized by an aroylation reaction of cyclohexyl-substituted cyclopentadienyl anions. Compound 1 crystallizes in the triclinic space group P(-)1, with a = 7.0419(5) A, b = 11.9360(8) A, c = 15.6470(11) A, alpha = 85.1440(10) degrees, beta = 78.1140(10) degrees, gamma ... |
12230394 | First Cu(II) diamondoid net with 2-fold interpenetrating frameworks. The role of anions in the construction of the supramolecular arrays. | The synthesis and crystal structure of the three-dimensional coordination polymer of an angular dipyridyl ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (L) and Cu(ClO(4))(2), exhibiting the first Cu(II) diamondoid network with 2-fold interpenetration, ([Cu(L)(2)(H(2)O)(2)](ClO(4))(OH)(H(2)O)(2.5))(n) (1), together with th... |
12230573 | Supramolecular calsequestrin complex. | As recently demonstrated by overlay assays using calsequestrin-peroxidase conjugates, the major 63 kDa Ca(2+)-binding protein of the sarcoplasmic reticulum forms complexes with itself, and with junctin (26 kDa), triadin (94 kDa) and the ryanodine receptor (560 kDa) [Glover, L., Culligan, K., Cala, S., Mulvey, C. & Ohle... |
12231254 | Asymmetrical distribution of the Schaffer projections within the apical dendrites of hippocampal field CA1. | Continuous current source densities were calculated in two dimensions (proximo-distal vs. medio-lateral) from slices of hippocampal field CA1 placed on a 64-electrode array in the presence of GABA blockers. The synaptic sink generated by stimulation of the Schaffer-commissural fibers spread across the extent of field C... |
12227773 | Bisbinaphthyl macrocycle-based highly enantioselective fluorescent sensors for alpha-hydroxycarboxylic acids. | [structure: see text] Bisbinaphthyl-based macrocycles are found to carry out highly enantioselective fluorescent recognition of alpha-hydroxycarboxylic acids. It is observed that within a certain concentration range, one enantiomer of the chiral acids can increase the fluorescence intensity of the macrocycles by 2-3-fo... |
12227762 | Highly enantioselective photocyclization of 1-alkyl-2-pyridones to beta-lactams in inclusion crystals with optically active host compounds. | [reaction: see text] Upon photoirradiation of a 1:1 inclusion complex of (-)-3 and 2-alkyl-1-pyridone (1) (R = Et, n-Pr, i-Pr, n-Bu, i-Bu) in the solid state, optically active beta-lactams (2) of 91-99.5% ee were obtained in good yield. |
12227760 | Medium-dependent type selectivity in photoreactions of a crown ether-annelated dibenzobarrelene derivative. | [reaction: see text] A concept for modifying the photochemical properties of a dibenzobarrelene derivative by the combination of supramolecular assembly and solid-state photochemistry is presented. The irradiation of dibenzobarrelene 1b and alkali metal complexes thereof (1:1) in acetonitrile or benzene solution leads ... |
12227751 | Synthesis, complexation, and supramolecular assembly of 21,30-dithia-17,25-dimethyl-1,4,7,10,13- pentaoxa[13.3.3](1,2,6)cyclophane. | [structure: see text] A crownophane consisting of a dithia[3.3]metacyclophane moiety was synthesized by employing a high dilution method. The crystal structure and complexation behavior of this crownophane was studied. A hydrogen-bonded linear supramolecular assembly using anion-Na(+)-crownophane-solvent as a synthon w... |
12227744 | Supramolecular association of dopamine with immobilized fluorescent probes. | We have designed a two-step procedure to coat silica particles with fluorescent 2,7-diazapyrenium dications. The electron-deficient character of the dications encourages the association of dopamine at the particle/water interface. The supramolecular event produces a significant decrease in the fluorescence intensity. M... |
12227741 | A new approach to heterofunctionalized dendrimers: a versatile triallyl chloride core. | A reactive triallyl chloride moiety was prepared as a suitable core for aliphatic polyether dendrons. In addition to allowing access to fourth generation dendrimers, this core contains three alkene functionalities that can be modified after dendrimer formation and used for further dendritic growth. |
12227827 | Convergent synthesis of isomeric pairs of metallocene-containing polyether macrocycles. | A general method for rapid construction of metallocene-based hosts is described. Treatment of polyether bridged bis(diphenylacetylenes) with a source of cyclopentadienyl cobalt at high temperature leads, via macrocyclization and capture of the intermediate cyclobutadiene, to macrocyclic systems tethered to an integral ... |
12227813 | Synthesis and structure of a stabilized 10-membered cyclic enediyne. | The synthesis and structure of an acetal protected 10-membered cyclic enediyne-1,2-diol rac-10 is reported. The conformational constrain of the unsaturated macrocycle by the acetal protection group prevents the thermal cyclization reaction of the endiyne during synthesis and purification. |
12227791 | Silver complexes with unsaturated thiacrown ethers: inclusion behavior of conformationally restricted macrocycles. | The reactions of 18- and 21-membered unsaturated thiacrown ethers, 18-UT-6 and 21-UT-7, with CF(3)COOAg in acetone afforded novel silver(I) complexes Ag(I)(18-UT-6)(CF(3)COO) and Ag(I)(2)(21-UT-7)(CF(3)COO)(2), respectively. The crystal structure of Ag(I)(18-UT-6)(CF(3)COO) shows that the silver atom occupies the cavit... |
12227790 | Carbonylation reactions of iodoarenes with PAMAM dendrimer-palladium catalysts immobilized on silica. | Palladium complexes immobilized onto generation 0-3 PAMAM dendrimers supported on silica were used as catalysts for the carbonylation of iodobenzene in methanol to form methyl benzoate. High yields were obtained and the catalyst was recycled 4-5 times without significant loss of activity. The carbonylation reaction was... |
12224968 | A novel approach for the sequential backbone assignment of larger proteins: selective intra-HNCA and DQ-HNCA. | Sequential assignment of backbone resonances in larger proteins can be achieved by recording two or more complementary triple-resonance NMR spectra of deuterated proteins. For such proteins, higher fields and experiments based on the TROSY method provide the needed resolution and sensitivity. However, increasingly rapi... |
12224964 | Synthesis and properties of water-soluble asterisk molecules. | An asterisk is comprised of six semirigid arms projecting from a benzene nucleus. In the case at hand, asterisks were synthesized with one, two, or three aromatic rings (connected by sulfur atoms) in each of the six arms. A phosphomonoester at the termini of each arm solubilized the asterisks in water. The colloidal pr... |
12224954 | Helical rosette nanotubes with tunable chiroptical properties. | On the basis of transmission electron microscopy (TEM), dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), and circular dichroism (CD) studies, compound 1 was shown to exist mainly in two states: (a) At high concentration (> or =1 mM, in methanol), 1 undergoes hierarchical self-assembly to generate ro... |
12224934 | A metal-organic bilayer open framework with a dynamic component: single-crystal-to-single-crystal transformations. | A metal-organic bilayered open framework, [Ni2(C26H52N10)]3[BTC]4.6C5H5N.36H2O (BOF-1, 1), has been prepared by the self-assembly of a new bismacrocyclic nickel(II) complex [Ni2(C26H52N10)(Cl)4].H2O (A) and sodium 1,3,5-benzenetricarboxylate (Na3BTC) in the mixture of water/DMSO/pyridine. The X-ray crystal structure of... |
12224923 | First thermally responsive supramolecular polymer based on glycosylated amino acid. | In materials science, a dynamic property sensitive to an environmental change (heat, light, electric current, pH, and other chemical or physical changes) is indispensable for intelligent materials. Such organic materials, however, are very limited even in conventional polymers. This paper clearly demonstrates that, reg... |
12224917 | Supramolecular structures of polyoxomolybdate-based giant molecules in aqueous solution. | A combination of static and dynamic laser light-scattering techniques was employed to study the supramolecular structures of polyoxomolybdate-based giant molecules in aqueous solution. Convincing evidences indicate that the spherical aggregates have unique vesicle-like structures. A model is built up based on solid exp... |
12223239 | ZL-DHP lignin model compound at the air-water interface. | In this paper we present our surface chemistry studies of enzymatically polymerized, poly-coniferyl alcohol lignin model compound (dehydrogenate polymer a.k.a. ZL-DHP) at the air-water interface. Using the CHCl(3)/MeOH (5:1 v/v) spreading solvent, we found an average molecular area of ZL-DHP of approximately 1200 A(2).... |
12223268 | Chemical biology of dynamic combinatorial libraries. | Dynamic combinatorial chemistry (DCC) is a recently introduced supramolecular approach to generate libraries of chemical compounds based on reversible exchange processes. The building elements are spontaneously and reversibly assembled to virtually encompass all possible combinations, allowing for simple one-step gener... |
12221119 | Modulation of cellular cholesterol transport and homeostasis by Rab11. | To analyze the contribution of vesicular trafficking pathways in cellular cholesterol transport we examined the effects of selected endosomal Rab proteins on cholesterol distribution by filipin staining. Transient overexpression of Rab11 resulted in prominent accumulation of free cholesterol in Rab11-positive organelle... |
12220848 | Structure-activity relationships of poly(L-lysines): effects of pegylation and molecular shape on physicochemical and biological properties in gene delivery. | The influence of shape, molecular weight and pegylation of linear, grafted, dendritic and branched poly-L-lysines on their DNA delivery properties were investigated. DNA binding, condensation, complex size and morphology, cell uptake and transfection efficiency were determined. Most polylysines condense DNA, linear pol... |
12220185 | The two histidine axial ligands of the primary electron donor chlorophylls (P700) in photosystem I are similarly perturbed upon P700+ formation. | The extent of delocalization of the positive charge in the oxidized dimer of chlorophyll (Chl) constituting P700, the primary electron donor of photosystem I (PSI), has been investigated by analyzing the perturbation upon P700(+) formation of infrared (IR) vibrational modes of the two His axial ligands of the two P700 ... |
12218101 | Colocalization of the B cell receptor and CD20 followed by activation-dependent dissociation in distinct lipid rafts. | The B cell Ag receptor (BCR) and CD20, a putative calcium channel, inducibly associate with cholesterol-dependent membrane microdomains known as lipid rafts. A functional association between the BCR and CD20 is suggested by the effects of CD20-specific mAbs, which can modulate cell cycle transitions elicited by BCR sig... |
12218094 | Cutting edge: quantitative imaging of raft accumulation in the immunological synapse. | Although the accumulation of lipid rafts at the immunological synapse is now well accepted, the degree of the accumulation, the localization within the fine structure of the immunological synapse, and the region from which lipid rafts are recruited have not been defined. In this work we show that lipid rafts preferenti... |
12217048 | Formation of fibrin gel in fibrinogen-thrombin system: static and dynamic light scattering study. | The dynamics of thrombin-induced fibrin gel formation was investigated by means of static and dynamic light scattering. The decay time distribution function, obtained by the dynamic light scattering, clearly revealed a stepwise gelation process: the formation of fibrin and protofibril from fibrinogen followed by the la... |
12217033 | Mercury intrusion porosimetry, nitrogen adsorption, and scanning electron microscopy analysis of pores in skin. | Stability of collagenous matrixes such as skin and leather with respect to changes in their dimensions on heating has long been correlated with degree and type of cross links formed and short-range ordering in angstrom unit scales. Macroscopic dimensional changes may be expected to involve alterations in the long-range... |
12213209 | Furrow-specific endocytosis during cytokinesis of zebrafish blastomeres. | Mutations affecting endocytosis, such as those in clathrin and dynamin, unexpectedly cause defects in cytokinesis in a number of organisms. To explore the relationship between endocytosis and cytokinesis, we used the relatively large cells of the transparent zebrafish embryo. Using fluorescent markers for fluid-phase a... |
12086580 | A novel, kinetically stable, catalytically active, all-ferric, nitrite-bound complex of Paracoccus pantotrophus cytochrome cd1. | The oxidized form of Paracoccus pantotrophus cytochrome cd(1) nitrite reductase, as isolated, has bis-histidinyl co-ordination of the c haem and His/Tyr co-ordination of the d(1) haem. On reduction, the haem co-ordinations change to His/Met and His/vacant respectively. If the latter form of the enzyme is reoxidized, a ... |
12069686 | Irreversible inhibition of the bacterial cysteine protease-transpeptidase sortase (SrtA) by substrate-derived affinity labels. | We report on the first synthesis, kinetic evaluation and application of novel substrate-derived inhibitors against the Staphylococcus aureus cysteine protease-transpeptidase, sortase (staphylococcal surface protein sorting A, SrtA). The peptidyl-diazomethane and peptidyl-chloromethane analogues, Cbz (benzyloxycarbonyl)... |
12213706 | Development of a frozen cell array as a high-throughput approach for cell-based analysis. | Recent advances in molecular biology, human genetics, and functional genomics tremendously increase the number of molecular targets available for potential therapeutic and diagnostic use. To complement DNA array data, cost-efficient high-throughput technologies providing reliable information at the protein level need t... |
12209002 | Microbial cellulose utilization: fundamentals and biotechnology. | Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological... |
12209001 | Communication among oral bacteria. | Human oral bacteria interact with their environment by attaching to surfaces and establishing mixed-species communities. As each bacterial cell attaches, it forms a new surface to which other cells can adhere. Adherence and community development are spatiotemporal; such order requires communication. The discovery of so... |
12207515 | EXAFS investigations of the mechanism of facilitated ion transfer into a room-temperature ionic liquid. | The Sr(II)-crown ether complexes formed in a room-temperature ionic liquid (RTIL), 1-methyl-3-pentylimidazolium bis[(trifluoromethyl)sulfonyl]amide, have been studied by X-ray absorption fine structure measurements at the Sr K-edge. When a Sr(NO(3))(2)-crown ether complex is directly dissolved in a water-saturated RTIL... |
12207511 | The topochemical 1,6-polymerization of a triene. | The first topochemical 1,6-polymerization of a triene has been observed. The required supramolecular structure for this polymerization was achieved by the pi-pi stacking of the isonicotinate functionality. The crystal environment of this polymerization reaction controlled both the molecular and supramolecular structure... |
12207463 | Sensitive micellar electrokinetic chromatography-laser-induced fluorescence method to analyze chiral amino acids in orange juices. | In this work a new method to detect the existence of chiral amino acids in orange juice is presented. The method employs beta-cyclodextrins and micellar electrokinetic chromatography with laser-induced fluorescence (MEKC-LIF) to separate and detect L- and D-amino acids (L-aa and D-aa) previously derivatized with fluore... |
12208454 | Characterization of the complexes of furosemide with 2-hydroxypropyl-beta-cyclodextrin and sulfobutyl ether-7-beta-cyclodextrin. | The purpose of this study was to prepare and characterize complexes of furosemide with 2-hydroxypropyl-beta-cyclodextrin (2-HP-beta-CD) and sulfobutyl ether-7-beta-cyclodextrin (SBE-7-beta-CD). Solid complexes of furosemide with 2-HP-beta-CD and SBE-7-beta-CD were prepared by using both a freeze-drying and kneading met... |
12210984 | Inhibition of adhesion of type 1 fimbriated Escherichia coli to highly mannosylated ligands. | The inhibitory potencies of a number of mannosides, di- and trivalent mannosides, a set of mannose-terminating dendrimers, and five types of mannose-bearing neoglycoproteins were determined by using a binding assay that measures the binding of (125)I-labeled, highly mannosylated neoglycoprotein to a type 1 fimbriated E... |
12208785 | Bradykinin potentiation by ACE inhibitors: a matter of metabolism. | 1. Studies in isolated cells overexpressing ACE and bradykinin type 2 (B(2)) receptors suggest that ACE inhibitors potentiate bradykinin by inhibiting B(2) receptor desensitization, via a mechanism involving protein kinase C (PKC) and phosphatases. Here we investigated, in intact porcine coronary arteries, endothelial ... |
12206679 | pH-controlled fluorescent emission in the nickel(II) complex of a bifunctional tetramine macrocycle. | In the Ni(II) complex of a reinforced tetramine macrocycle, equipped with both a sulfonamide pendant arm and a naphthalene fragment, light emission of the fluorophore is pH-controlled, as a result of a change of the geometry of the complex. |
12207319 | Separation of alkamides from Echinacea purpurea extracts by cyclodextrin-modified micellar electrokinetic chromatography. | Separation of nine important alkyl methylbutyl- and isobutylamides (known as alkamides) obtained from Echinacea purpurea extracts was investigated by using cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC). Hydrophobic alkamides interact strongly with the micelles from the most common surfactants u... |
12207317 | Analysis of aminophospholipid molecular species by methyl-beta-cyclodextrin modified micellar electrokinetic capillary chromatography with laser-induced fluorescence detection. | Micellar electrokinetic capillary chromatography (MEKC) with laser-induced fluorescence detection is used for the analysis of three classes of aminophospholipids: phosphatidylethanolamine (PE), phosphatidylserine (PS), and lysophosphatidylethanolamine (LPE) molecular species. 3-(2-Furoyl) quinoline-2-carboxaldehyde (FQ... |
12207314 | Enantioselective analysis of ibuprofen in human plasma by anionic cyclodextrin-modified electrokinetic chromatography. | This paper reports the development of a rapid method for the enantioselective analysis of the nonsteroidal anti-inflammatory drug ibuprofen in human plasma by capillary electrophoresis employing the anionic cyclodextrin-modified electrokinetic chromatography mode. Sample cleanup was carried out by acidification with HC... |
12207312 | Comparative enantioseparations with native beta-cyclodextrin and heptakis-(2-O-methyl- 3,6-di-O-sulfo)-beta-cyclodextrin in capillary electrophoresis. | Twenty-three cationic chiral analytes were resolved in capillary electrophoresis using native beta-cyclodextrin and single isomer heptakis-(2-O-methyl-3,6-di-O-sulfo)-beta-cyclodextrin as chiral selectors. For 12 of 16 chiral analytes resolved with both chiral selectors the enantiomer migration order was opposite. In s... |
12207311 | Octakis-6-sulfato-gamma-cyclodextrin as additive for capillary electrokinetic chromatography of dibenzoazepines: carbamazepine, oxcarbamazepine and their metabolites. | Single isomer octakis-(2,3-dihydroxy-)6-sulfato-gamma-cyclodextrin used as pseudostationary phase of the background electrolyte interacts with dibenzo[b,f]azepines (consisting of a condensed 3-ring system) and forms negatively charged complexes. Hydroxygroups in position 2 and 3 at carbamazepine increase the extent of ... |
12207310 | Illustration of a simple and versatile scheme for reversing enantiomeric elution order and facilitating enantiomeric impurity determination in capillary electrophoresis. | Determination of enantiomeric purity is most often done under overload conditions, which leads to deformed peaks. In general, the best resolutions are obtained when the small peak appears before the large peak in the electropherogram. To be able to determine the R(+)-impurity in the S(-)-form as well as the S(-)-impuri... |
12207308 | Combinatorial enantiomeric separation of diverse compounds using capillary array electrophoresis. | Combinatorial chiral separations were performed on a 96-capillary array electrophoresis system. A comprehensive enantioseparation protocol employing neutral and sulfated cyclodextrins as chiral selectors for common basic, neutral and acidic compounds was developed. By using only four judiciously chosen separation buffe... |
12207304 | On-line coupling of packed capillary electrochromatography with coordination ion spray-mass spectrometry for the separation of enantiomers. | Pressure-supported packed capillary electrochromatography (CEC) and packed capillary high-performance liquid chromatography (pHPLC) have been coupled on-line to electrospray ionization-mass spectrometry (ESI-MS) and coordination ion spray-mass spectrometry (CIS-MS). Separation of enantiomers of barbiturates and chlorin... |
12206911 | Is there a relationship between the supramolecular organization of the mitochondrial ATP synthase and the formation of cristae? | Blue native polyacrylamide gel electrophoresis (BN-PAGE) analyses of detergent mitochondrial extracts have provided evidence that the yeast ATP synthase could form dimers. Cross-linking experiments performed on a modified version of the i-subunit of this enzyme indicate the existence of such ATP synthase dimers in the ... |
12206892 | Supramolecular organisation of the photosynthetic chain in anoxygenic bacteria. | This minireview summarizes our present view of the supramolecular organization of the photosynthetic apparatus of Rhodobacter sphaeroides and Rhodobacter capsulatus. These two species present a close association between two reaction centers (RCs), one cytochrome (cyt) bc(1) and one cyt c. In R. sphaeroides, the RCs are... |
12205687 | Immunohistochemical and electron microscopic study of invasion and differentiation in spinal cord lesion of neural stem cells grafted through cerebrospinal fluid in rat. | Neurospheres were obtained by culturing hippocampal cells from transgenic rat fetuses (E16) expressing green fluorescent protein (GFP). The neurosphere cells were injected into the cerebrospinal fluid (CSF) through the 4th ventricle of young rats (4 weeks old) that had been given a contusion injury at T8-9 of the spina... |
12204572 | Studies of curcumin and curcuminoids. XXVII. Cyclodextrin complexation: solubility, chemical and photochemical stability. | Cyclodextrin complexes of the natural compound curcumin were prepared in order to improve the water solubility and the hydrolytic and photochemical stability of the compound. Complex formation resulted in an increase in water solubility at pH 5 by a factor of at least 10(4). The hydrolytic stability of curcumin under a... |
12204561 | Design of naltrexone-loaded hydrolyzable crosslinked nanoparticles. | A hydrolyzable crosslinker (N,O-dimethacryloylhydroxylamine (MANHOMA)) was synthesized by a modified method and was characterized using 1H-NMR, FTIR, and melting point determination. Naltrexone-loaded nanoparticles were prepared by copolymerization of poly(ethylene glycol)1000 monomethyl ether mono methacrylate (PEO-MA... |
12204954 | Serodiagnosis of mice minute virus and mouse parvovirus infections in mice by enzyme-linked immunosorbent assay with baculovirus-expressed recombinant VP2 proteins. | Mice minute virus (MMV) and mouse parvovirus (MPV) type 1 are the two parvoviruses known to naturally infect laboratory mice and are among the most prevalent infectious agents found in contemporary laboratory mouse colonies. Serologic assays are commonly used to diagnose MMV and MPV infections in laboratory mice; howev... |
12204946 | Augmentation of the lipopolysaccharide-neutralizing activities of human cathelicidin CAP18/LL-37-derived antimicrobial peptides by replacement with hydrophobic and cationic amino acid residues. | Mammalian myeloid and epithelial cells express various peptide antibiotics (such as defensins and cathelicidins) that contribute to the innate host defense against invading microorganisms. Among these peptides, human cathelicidin CAP18/LL-37 (L(1) to S(37)) possesses not only potent antibacterial activity against gram-... |
12204622 | The self-association of the drug acemetacin and its interactions and stabilization with beta-cyclodextrin in aqueous solution as inferred from NMR spectroscopy and HPLC studies. | Strongly concentration dependent, (1)H NMR chemical shifts of the non-steroidal anti-inflammatory drug acemetacin sodium salt (sodium [[1-(4-chlorobenzoyl)-5-methoxy-2-methylindol-3-yl]acetoxy]acetate), were observed in aqueous solution. Self-titration and nOe experiments, point to a self-association model where stacki... |
12201706 | Complexation of small molecules by open-ended resorcarene hosts. | [structure: see text] Sterically hindered tetraaminomethylated resorcarenes form inclusion complexes in CDCl(3) with acetonitrile and acetaldehyde, which are kinetically stable on the NMR time scale at 233 K. |
12202780 | Multivariate curve resolution: a powerful tool for the analysis of conformational transitions in nucleic acids. | A successful application is reported of the multivariate curve resolution alternating least-squares method (MCR-ALS) for the analysis of nucleic acid melting and salt-induced transitions. Under conditions where several structures co-exist in a conformational equilibrium, MCR-ALS analysis of the UV and circular dichrois... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.