id stringlengths 4 8 | title stringlengths 1 642 | abstract stringlengths 50 17.9k |
|---|---|---|
9188063 | Characterization of complexes of oligonucleotides with polyamidoamine starburst dendrimers and effects on intracellular delivery. | This study evaluates polyamidoamine PAMAM "starburst" dendrimers (generation 3, Mr 6909) as a potential delivery vehicle for oligonucleotides. Complexes between dendrimer and phosphorothioate oligonucleotides were observed by agarose gel electrophoresis and were positive, negative, or neutral in charge depending on sto... |
9188054 | Influence of alpha-cyclodextrin and hydroxyalkylated beta-cyclodextrin derivatives on the in vitro corneal uptake and permeation of aqueous pilocarpine-HCl solutions. | Interactions in aqueous solution between pilocarpine hydrochloride (P-HCl), a rather hydrophilic drug with good water solubility, and various cyclodextrins (CDs) were described recently. To assess the influence of CDs on the diffusion behavior of pilocarpine, in vitro studies were performed using porcine or bovine corn... |
9182657 | Partitioning of the Golgi apparatus during mitosis in living HeLa cells. | The Golgi apparatus of HeLa cells was fluorescently tagged with a green fluorescent protein (GFP), localized by attachment to the NH2-terminal retention signal of N-acetylglucosaminyltransferase I (NAGT I). The location was confirmed by immunogold and immunofluorescence microscopy using a variety of Golgi markers. The ... |
9184012 | The first living systems: a bioenergetic perspective. | The first systems of molecules having the properties of the living state presumably self-assembled from a mixture of organic compounds available on the prebiotic Earth. To carry out the polymer synthesis characteristic of all forms of life, such systems would require one or more sources of energy to activate monomers t... |
9182557 | Defining the minimal domain of the Plasmodium falciparum protein MESA involved in the interaction with the red cell membrane skeletal protein 4.1. | During part of its life cycle, the protozoan parasite Plasmodium falciparum lives within the human red blood cell and modifies both the structural and functional properties of the red cell. It does this by synthesizing a number of polypeptides that it transports into the red cell cytoplasm and to the red cell membrane.... |
9180729 | Histologic effects of the high-energy pulsed CO2 laser on photoaged facial skin. | To delineate the histologic effects of laser resurfacing at photoaged skin, a protocol was designed to biopsy laser test sites in conjunction with adjacent actinically damaged skin at the time of rhytidectomy. Five patients with photodamaged skin underwent resurfacing of the preauricular region to examine the effect of... |
9177210 | Heme compounds in dinosaur trabecular bone. | Six independent lines of evidence point to the existence of heme-containing compounds and/or hemoglobin breakdown products in extracts of trabecular tissues of the large theropod dinosaur Tyrannosaurus rex. These include signatures from nuclear magnetic resonance and electron spin resonance that indicate the presence o... |
9177351 | Ligand-specific oligomerization of T-cell receptor molecules. | T cells initiate many immune responses through the interaction of their T-cell antigen receptors (TCR) with antigenic peptides bound to major histocompatibility complex (MHC) molecules. This interaction sends a biochemical signal into the T cell by a mechanism that is not clearly understood. We have used quasielastic l... |
9174200 | Itraconazole resistance in Aspergillus fumigatus. | Invasive aspergillosis is an increasingly frequent opportunistic infection in immunocompromised patients. Only two agents, amphotericin B and itraconazole, are licensed for therapy. Itraconazole acts through inhibition of a P-450 enzyme undertaking sterol 14alpha demethylation. In vitro resistance in Aspergillus fumiga... |
9172351 | Isolation and characterization of fimbriae from a sparsely fimbriated strain of Porphyromonas gingivalis. | Porphyromonas gingivalis W50 (ATCC 53978) possesses the gene for fimbriae; however, the surface-expressed fimbriae are sparse and have not been previously isolated and characterized. We purified fimbriae from strain W50 to homogeneity by ammonium sulfate precipitation and reverse-phase high-performance liquid chromatog... |
9171091 | Effects of natural and synthetic polyamines on the conformation of an oligodeoxyribonucleotide with the estrogen response element. | We studied the effects of natural and synthetic polyamines on the conformation of an oligodeoxyribonucleotide (ODN1) harboring the estrogen response element (ERE) by circular dichroism (CD) spectroscopy and polyacrylamide gel electrophoresis. Putrescine and spermidine had no marked effect on the CD spectrum of ODN1. In... |
9171080 | A three-dimensional working model for a guide RNA from Trypanosoma brucei. | RNA editing in protozoan parasites is a mitochondrial RNA processing reaction in which exclusively uridylate residues are inserted into, and less frequently deleted from, pre-mRNAs. Molecules central to the process are so-called guide RNAs (gRNAs) which function as templates in the reaction. For a detailed molecular un... |
9171077 | NonO enhances the association of many DNA-binding proteins to their targets. | NonO is an unusual nucleic acid binding protein not only in that it binds both DNA and RNA but that it does so via functionally separable domains. Here we document that NonO enhances the binding of some (E47, OTF-1 and OTF-2) but not all (PEA3) conventional sequence-specific transcription factors to their recognition s... |
9171413 | 2-chloromuconate and ClcR-mediated activation of the clcABD operon: in vitro transcriptional and DNase I footprint analyses. | In Pseudomonas putida, the plasmid-borne clcABD operon encodes enzymes involved in 3-chlorocatechol degradation. Previous studies have demonstrated that these enzymes are induced when P. putida is grown in the presence of 3-chlorobenzoate, which is converted to 3-chlorocatechol, and that ClcR, a LysR-type regulator, is... |
9169533 | Neurexin is expressed on nerves, but not at nerve terminals, in the electric organ. | Neurexins are highly variable transmembrane proteins hypothesized to be nerve terminal-specific cell adhesion molecules. As a test of the hypothesis that neurexin is restricted to the nerve terminal, we examined neurexins in the electric organ of the elasmobranch electric fish. Specific antibodies generated against the... |
9169532 | RNA transport in dendrites: a cis-acting targeting element is contained within neuronal BC1 RNA. | In nerve cells, a select group of RNAs has been localized to dendritic domains. Here we have examined dendritic RNA transport in sympathetic neurons in primary culture, using a microinjection protocol with neuronal BC1 RNA and with BC1-derived sequence segments. After cytoplasmic microinjection, full-length BC1 RNA was... |
9169732 | Yersinia enterocolitica serotype O:3 alters the expression of serologic HLA-B27 epitopes on human monocytes. | The expression of serologic HLA-B27 epitopes on leukocytes of patients with reactive arthritis or ankylosing spondylitis has been shown to be modified in the course of the disease. The purpose of this work was to study whether phagocytosis of arthritis-triggering microbes in vitro alters the expression of HLA-B27 molec... |
9169727 | Toxicity and immunogenicity of a verotoxin 1 mutant with reduced globotriaosylceramide receptor binding in rabbits. | The verotoxins (VT1 and VT2), produced by strains of enterohemorrhagic Escherichia coli, have been implicated in the pathogenesis of hemorrhagic colitis and the hemolytic uremic syndrome. To better understand the role of globotriaosylceramide (Gb3) receptor binding by the verotoxins in disease production, we examined t... |
9168056 | Quantifying rolling adhesion with a cell-free assay: E-selectin and its carbohydrate ligands. | Rolling of neutrophils over stimulated endothelial cells is a prerequisite to firm attachment and subsequent transendothelial migration during the inflammatory response. The selectin family of adhesion molecules are thought to mediate rolling by binding counter-receptors that present carbohydrates, such as sialyl Lewis... |
9168049 | Polarized Raman spectroscopy of double-stranded RNA from bacteriophage phi6: local Raman tensors of base and backbone vibrations. | Raman tensors for localized vibrations of base (A, U, G, and C), ribose and phosphate groups of double-stranded RNA have been determined from polarized Raman measurements on oriented fibers of the genomic RNA of bacteriophage phi6. Polarized Raman intensities for which electric vectors of both the incident and scattere... |
9168043 | An electrochemical approach of the redox behavior of water insoluble ubiquinones or plastoquinones incorporated in supported phospholipid layers. | Physiological mole fractions of long isoprenic chain ubiquinone (UQ[10]) and plastoquinone (PQ9) were incorporated inside a supported bilayer by vesicle fusion. The template of the bilayer was an especially designed microporous electrode that allows the direct electrochemistry of water insoluble molecules in a water en... |
9168037 | Bending elasticities of model membranes: influences of temperature and sterol content. | Giant liposomes obtained by electroformation and observed by phase-contrast video microscopy show spontaneous deformations originating from Brownian motion that are characterized, in the case of quasispherical vesicles, by two parameters only, the membrane tension sigma and the bending elasticity k(c). For liposomes co... |
9168036 | Adsorption of bovine prothrombin to spread phospholipid monolayers. | The interaction of bovine prothrombin with phospholipids was measured, using as the lipid source monolayers spread at the air-buffer interface. Fluorescence spectroscopy was implemented to determine the equilibrium concentration of free prothrombin in the aqueous subphase of the protein-monolayer suspensions, in a cont... |
9168027 | Time-resolved charge translocation by the Ca-ATPase from sarcoplasmic reticulum after an ATP concentration jump. | Time-resolved measurements of currents generated by Ca-ATPase from fragmented sarcoplasmic reticulum (SR) are described. SR vesicles spontaneously adsorb to a black lipid membrane acting as a capacitive electrode. Charge translocation by the enzyme is initiated by an ATP concentration jump performed by the light-induce... |
9168026 | Fluctuation-driven directional flow in biochemical cycle: further study of electric activation of Na,K pumps. | Directional flow of information and energies is characteristic of many types of biochemical reactions, for instance, ion transport, energy coupling during ATP synthesis, and muscle contraction. Can a fluctuating force field, or a noise, induce such a directional flux? Previous work has shown that Na,K-ATPase of human e... |
9168025 | Helix bending in alamethicin: molecular dynamics simulations and amide hydrogen exchange in methanol. | Molecular dynamics simulations of alamethicin in methanol were carried out with either a regular alpha-helical conformation or the x-ray crystal structure as starting structures. The structures rapidly converged to a well-defined hydrogen-bonding pattern with mixed alpha-helical and 3(10)-helical hydrogen bonds, consis... |
9168024 | Shaker pore structure as predicted by annealed atomic simulation using symmetry and novel geometric restraints. | Recent studies making use of channel-blocking peptides as molecular calipers have revealed the architecture of the pore-forming region of Shaker-type potassium channels. Here we show that the low-resolution, experimentally derived geometric information can be incorporated as restraints within the context of an annealed... |
9168021 | Role of water on unfolding kinetics of helical peptides studied by molecular dynamics simulations. | Molecular dynamics simulations have been carried out with four polypeptides, Ala13, Val(13), Ser13, and Ala4Gly5Ala4, in vacuo and with explicit hydration. The unfolding of the polypeptides, which are initially fully alpha-helix in conformation, has been monitored during trajectories of 0.3 ns at 350 K. A rank of Ala <... |
9166423 | Crucial role of the residue R280 at the F'-G' loop of the human granulocyte/macrophage colony-stimulating factor receptor alpha chain for ligand recognition. | The receptor for granulocyte/macrophage colony-stimulating factor (GM-CSF) is composed of two chains, alpha and betac. Both chains belong to the superfamily of cytokine receptors characterized by a common structural feature, i.e., the presence of at least two fibronectin-like folds in the extracellular domain, which wa... |
9166401 | Nup84, a novel nucleoporin that is associated with CAN/Nup214 on the cytoplasmic face of the nuclear pore complex. | The short filaments extending from the cytoplasmic face of nuclear pore complexes are thought to contain docking sites for nuclear import substrates. One component of these filaments is the large O-linked glycoprotein CAN/Nup214. Immunoprecipitation studies carried out under nondenaturing conditions, and using a variet... |
9182721 | Membrane association, localization and topology of rat inositol 1,4,5-trisphosphate 3-kinase B: implications for membrane traffic and Ca2+ homoeostasis. | We previously reported the isolation of a rat cDNA clone encoding a protein with significant sequence homology to the B isoform of human myo-inositol 1,4,5-trisphosphate 3-kinase (IP3 3-kinase B); this protein was thus designated rat IP3 3-kinase B [Thomas, Brake, Luzio, Stanley and Banting (1994) Biochim. Biophys. Act... |
9159086 | From nucleoporins to nuclear pore complexes. | One of the largest supramolecular assemblies in the eukaryotic cell, the nuclear pore complex, is now being dissected into its numerous molecular constituents. The combined use of biochemistry and genetics in yeast has made this rapid development possible. Although less is known about vertebrate nucleoporins, the first... |
9153315 | DNA binding and phasing analyses of Tn5 transposase and a monomeric variant. | Both full-length Tn 5 transposase and a COOH-terminal truncated monomeric form of the protein,n369, have been shown to specifically bind end sequences at comparable affinities. In addition, both proteins distort the target sequence in a similar manner, as determined by a circular permutation assay. In this study,nEK54,... |
9151757 | Temperature dependency of basal and evoked release of amino acids and calcitonin gene-related peptide from rat dorsal spinal cord. | Moderate hypothermia significantly diminishes consequences of spinal and cerebral anoxia. One component of this neuroprotection has been hypothesized to be suppression of excitotoxic transmitter release. Whether this suppression is attributable to reduced hypoxic injury that induces release or an alteration of the rele... |
9151838 | Incorporation of Pr160(gag-pol) into virus particles requires the presence of both the major homology region and adjacent C-terminal capsid sequences within the Gag-Pol polyprotein. | The determinants critical for the incorporation of Pr160(gag-pol) into human immunodeficiency virus type 1 (HIV-1) particles were examined by cotransfecting cells with (i) a plasmid expressing wild-type Gag protein and (ii) a series of chimeric Gag-Pol expression plasmids in which individual murine leukemia virus (MLV)... |
9667843 | Structural analysis of nucleic acid aptamers. | Solution structures and hydrogen exchange characteristics of ligand-RNA aptamer and ligand-DNA aptamer complexes have been solved within the past year. The ligands range from cofactors to amino acids, nucleotides, aminoglycoside antibiotics and peptides that are targeted by the nucleic acid aptamers with high specifici... |
21639296 | Separation and determination of polycyclic aromatic hydrocarbons by solid phase microextraction/cyclodextrin-modified capillary electrophoresis. | A sensitive method for the determination of polycyclic aromatic hydrocarbons (PAHs) by solid phase microextraction coupled with cyclodextrin (CD)-modified capillary electrophoresis (CE) using UV detection has been developed. A glass fiber was prepared and used for absorbing 16 EPA priority PAHs from diluted samples unt... |
11671689 | Effect of Cation-Complexing Agents on the Ba(II)-Assisted Basic Ethanolysis of Phenyl Acetate: From Cation Deactivation to Cation Activation. | A thorough investigation of the effect of adding cation complexing agents on the barium-assisted basic ethanolysis of phenyl acetate shows that any catalytic activity disappears upon sequestration of the metal ion by cryptand 222, but addition of the crown ethers 18C6, 15C5, and 12C4 yields ternary complexes of 1:1:1 (... |
11671686 | Translational Isomerism in Some Two- and Three-Station [2]Rotaxanes. | The template-directed syntheses of three [2]rotaxanes are described. They all have dumbbell components, with both hydroquinone and resorcinol rings inserted into polyether chains terminated by tetraarylmethane stoppers, that become encircled during the key self-assembly processes by the tetracationic cyclophane, cyclob... |
11669866 | Synthesis, Characterization, and Electrochemistry of Heterometallic Dendrimers. | A method for the synthesis of new heterometallic dendritic molecules containing organoplatinum centers is reported. Reaction of Pt(2)Me(4)(&mgr;-SMe(2))(2) with bpy-Fc(2) (1) (bpy-Fc(2) = 4,4'-bis(ferrocenylvinyl)-2,2'-bipyridine) gave the platinum(II) complex PtMe(2)(bpy-Fc(2)) (2). Complex 2 undergoes oxidative addit... |
11669844 | Synthesis, Reactivity, and Structure of [H(13)O(6)][PtCl(5)(H(4)O(2))].2(18-cr-6): A Crown Ether Complex of a Pentachloroaquaplatinic Acid with an [H(13)O(6)](+) Cation in a Cage of Three Crown Ether Molecules. | An aqueous solution of H(2)[PtCl(6)].6 H(2)O reacts with crown ether 18-crown-6 to give [H(13)O(6)][PtCl(5)(H(4)O(2))]. 2(18-cr-6)(1) (1) and (H(3)O)(2)[PtCl(6)].2(18-cr-6) (2a). In the presence of HCl, only 2a is formed; in an analogous manner, (H(3)O)(2)[PtCl(6)].2(15-cr-5).2 H(2)O (2b) and (H(3)O)(2)[PtCl(6)].2(DCH-... |
11669833 | Synthesis, Photophysics, and Electrochemistry of Ruthenium(II) Polypyridine Complexes with Crown Ether Pendants. | A series of ruthenium(II) polypyridine complexes with a crown ether-containing ligand dipyrido[3,2-a:2',3'-c]phenazo-15-crown-5 (dppzc) have been synthesized and characterized and their photophysics and electrochemistry studied. The photoredox reactivities of [Ru(bpy)(2)(dppzc)](2+) have also been investigated by Stern... |
11038541 | The role of London forces in defining noncentrosymmetric order of high dipole moment-high hyperpolarizability chromophores in electrically poled polymeric thin films. | Graphs of second harmonic generation coefficients and electro-optic coefficients (measured by ellipsometry, attenuated total reflection, and two-slit interference modulation) as a function of chromophore number density (chromophore loading) are experimentally observed to exhibit maxima for polymers containing chromopho... |
9484656 | The effect of beta-cyclodextrins as buffer additives on the (capillary) electrophoretic separation of peptides and proteins. | Electrophoretic and chromatographic experiments performed under straightforward conditions do not always provide satisfactory resolution. An obvious approach, then, is to manipulate the magnitude of relevant separation parameters, such as charge (zeta potential), size, and hydrophobicity, all of which can be accomplish... |
9474262 | Bioelectrorheological model of the cell. 7. Cellular deformation in the presence of cytochalasin B. | The influence of cytochalasin B on the mechanical properties of Neurospora crassa cells subjected to a periodic electric field was investigated. Shear and extensional deformations were considered and studied separately. Conditions were found under which shear deformations become irreversible. Rheological models helped ... |
9408831 | Influence of mass transfer and surface ligand heterogeneity on quantitative BIAcore binding data. Analysis of the interaction of NC10 Fab with an anti-idiotype Fab'. | The interaction of monovalent Fab fragments of NC10, an antiviral neuraminidase antibody, and the anti-idiotype antibody 3-2G12 has been used as a model system to demonstrate experimentally the influence of non-ideal binding effects on BIAcore binding data. Because the association rate constant for these two molecules ... |
9408830 | Further refinement of the description of the ligand-binding characteristics for the galactoside-binding mistletoe lectin, a plant agglutinin with immunomodulatory potency. | The galactoside-binding lectin from mistletoe (Viscum album L.) is a biological response modifier, eliciting e.g. enhanced secretion of cytokines. This immunological activity warrants the further analysis of its ligand-binding properties with special attention paid to blood group epitopes. To avoid the microheterogenei... |
9408829 | Detection and characterization of weak affinity antibody antigen recognition with biomolecular interaction analysis. | In biological systems, weak-affinity interactions (association constant, Ka, of less than approximately 10(4) M-1) between biomolecules are common and essential to the integrity of such units. However, studies of weak biological interactions are difficult due to the scarcity of analytical methods available for the bios... |
9408828 | Ligand loading at the surface of an optical biosensor and its effect upon the kinetics of protein-protein interactions. | Optical biosensors are finding increasing use in the determination of kinetic and equilibrium constants for a variety of biomolecular interactions. Usually these biosensors require one biomolecule, the ligand, to be covalently attached to a hydrogel matrix which itself is bonded to the sensing surface. The ligands part... |
9408827 | The influence of the exocyclic amino group characteristic of GC base pairs on molecular recognition of specific nucleotide sequences in DNA by berenil and DAPI. | The expedient of preparing homologous DNA samples substituted with inosine for guanosine residues, 2,6-diaminopurine (DAP) for adenine residues, or both, has been used to investigate the role of the purine 2-amino group in determining the preferred binding sites for the drugs berenil [1,3-bis(4-phenylamidinium) triazen... |
9263849 | A comparison of heuristic search algorithms for molecular docking. | This paper describes the implementation and comparison of four heuristic search algorithms (genetic algorithm, evolutionary programming, simulated annealing and tabu search) and a random search procedure for flexible molecular docking. To our knowledge, this is the first application of the tabu search algorithm in this... |
9246414 | Comparative FISH-mapping of villin (VIL) gene in river buffalo, sheep and goat chromosomes. | Two genomic clones of the villin (VIL) gene were independently hybridized on river buffalo (Bubalus bubalis, BBU), sheep (Ovis aries, OAR) and goat (Capra hircus, CHI) chromosomes by using sequential fluorescence in situ hybridization (FISH) and R-banding (RBP- and RBA-banding). Clear hybridization signals revealed tha... |
9246413 | Geographical distribution of B chromosomes in the grasshopper Eyprepocnemis plorans, along a river basin, is mainly shaped by non-selective historical events. | The analysis of 19 populations of the grasshopper Eyprepocnemis plorans, collected along four rivers belonging to the Segura basin (Mundo, Benamor, Taibilla and Segura itself), has shown that the presence of B chromosomes ends abruptly in each river, coinciding with the existence of a narrow pass in which this grasshop... |
9246412 | Detection of alien chromatin conferring resistance to the beet cyst nematode (Heterodera schachtii Schm.) in cultivated beet (Beta vulgaris L.) using in situ hybridization. | Chromatin originating from wild beets of the genus Beta, section Procumbentes, has been investigated in nematode-resistant hybrid-derived lines of sugar beet (Beta vulgaris L.) by in situ hybridization using satellite, telomeric and ribosomal DNA repeats, a yeast artificial chromosome (YAC) and total genomic DNA as pro... |
9246411 | Conserved Y-chromosomal location of TSPY in Bovidae. | We determined the chromosomal location of TSPY, the testis-specific protein, Y-encoded, by fluorescence in situ hybridization (FISH) to chromosome spreads of cattle, goat and sheep. Using a cloned polymerase chain reaction (PCR) product of one bovine TSPY family member, we were able to show a conserved Y chromosomal lo... |
9246410 | Interphase arrangement of rye B chromosomes in rye and wheat. | Probes for B chromosome-specific sequences in the distal region of the long arm of the rye B have been used to investigate the interphase arrangement of the Bs in rye and in hexaploid wheat. The Lindström strain of wheat carries the rye Bs as additions. The number of in situ signals in nuclei with two, three and four B... |
9246409 | Comparative mapping of Xp22 genes in hominoids--evolutionary linear instability of their Y homologues. | Several genes located within or proximal to the human PAR in Xp22 have homologues on the Y chromosome and escape, or partly escape, inactivation. To study the evolution of Xp22 genes and their Y homologues, we applied multicolour fluorescence in situ hybridization (FISH) to comparatively map DNA probes for the genes AN... |
9246408 | Regional differences in the compaction of chromatin in human G0/G1 interphase nuclei. | The large-scale structure of chromatin corresponding to G- and R-bands in human G0/G1 interphase nuclei was compared. Fluorescence in situ hybridization (FISH) was used to measure the interphase distance between 42 pairs of probes separated by 0.1-1.5 Mbp. The probe pairs were derived from 21q22.2 and Xp21.3, G-band po... |
9215973 | Simultaneous determination of amoxycillin and clavulanic acid in pharmaceutical products by HPLC with beta-cyclodextrin stationary phase. | A simple, rapid and accurate method for simultaneous determination of amoxycillin and clavulanic acid using HPLC with beta-cyclodextrin stationary phase was developed. It involves the use of tetraethylammonium acetate (TEAA) as an additive reagent, methanol-buffer solution (pH 4.5) (35:65; v/v) as the mobile phase, det... |
9215961 | Comparison of aqueous and non-aqueous capillary electrophoresis for quantitative determination of morphine in pharmaceuticals. | Two capillary electrophoresis methods involving aqueous and non-aqueous electrophoresis media, respectively, have been compared for the quantitative determination of morphine in pharmaceutical preparations. In the aqueous system the separation from other opium alkaloids was achieved using 2,6-di-O-methyl-beta-cyclodext... |
9215958 | Optimized methods for capillary electrophoresis of tetracyclines. | Optimized methods for the analysis of some tetracyclines by capillary electrophoresis are described. Different buffer systems were employed for the separation of tetracycline, oxytetracycline and demeclocycline from their respective major impurities, including the 2-acetyl-2-decarboxamido derivatives. The influence of ... |
9215565 | Spectroscopic properties of an engineered maltose binding protein. | The maltose binding protein (MBP) has been site specifically labelled with a nitrobenzoxadiazole (NBD) group following mutation of a serine to a cysteine residue at position 337. The resulting protein shows a large ligand (maltose or beta-cyclodextrin) dependent increase in its steady-state fluorescence intensity. Anal... |
9203340 | Specificity of amylases and cyclodextrin-glucanotransferase in reactions with 2-deoxy-maltooligosaccharides. | 2-Deoxy-maltooligosaccharides of different chain length were tested as substrates for exo- and endo-amylases. Cleavage occurred with beta-amylase, yielding 2,2'-dideoxy-maltose, and with amyloglucosidase. With the alpha-amylase from Thermomonospora curvata tris-(2-deoxy)-maltotriose and the corresponding tetra- and pen... |
9203335 | 1H NMR relaxation study of a chitosan-cyclodextrin network. | The results of measurements of longitudinal and transverse proton relaxation times for a chemical network obtained by reacting chitosan with oxidized beta-cyclodextrin (beta-cyclodextrin polyaldehyde) are presented. The network was characterized by a 'two-component' transverse relaxation mechanism relative to structura... |
9200536 | Stereoselective determination of R-(-)- and S-(+)-prilocaine in human serum by capillary electrophoresis using a derivatized cyclodextrin and ultraviolet detection. | A capillary electrophoresis (CE) method for the quantification of R-(-)- and S-(+)-prilocaine in human serum was developed and validated. Stereoselective resolution was accomplished using 15 mM heptakis(2,6-di-methyl)-beta-cyclodextrin and 0.03 mM hexadecyltrimethylammonium bromide (HTAB) contained in 100 mM phosphate ... |
9195884 | Solution structure of the granular starch binding domain of Aspergillus niger glucoamylase bound to beta-cyclodextrin. | <h4>Background</h4>Carbohydrate-binding domains are usually small and physically separate from the catalytic domains of hydrolytic enzymes. Glucoamylase 1 (G1) from Aspergillus niger, an enzyme used widely in the food and brewing industries, contains a granular starch binding domain (SBD) which is separated from the ca... |
9195880 | The structure of a calmodulin mutant with a deletion in the central helix: implications for molecular recognition and protein binding. | <h4>Background</h4>Calmodulin (CaM) is the major calcium-dependent regulator of a large variety of important intracellular processes in eukaryotes. The structure of CaM consists of two globular calcium-binding domains joined by a central 28-residue alpha helix. This linker helix has been hypothesized to act as a flexib... |
9194599 | Capillary electrophoretic separation of tricyclic antidepressants using charged carboxymethyl-beta-cyclodextrin as a buffer additive. | Charged carboxymethyl-beta-cyclodextrin was successful in the capillary electrophoretic separation of a series of tricyclic antidepressants. The cyclodextrin alone was successful in the separation of carbamazepine, protriptyline, desipramine, clomipramine, and opipramol using a 3-(trimethoxysilyl)propyl methacrylate ca... |
9194595 | Quantitative description of analyte migration behavior based on dynamic complexation in capillary electrophoresis with one or more additives. | A comprehensive theory is proposed to describe the migration behavior of analytes in capillary electrophoresis (CE) when one or more additives are present in the buffer solution. This theory amalgamates and extends the previous work done by others. The capacity factor (k') in this theory is defined as the product of th... |
9194394 | [Molecular action mechanisms and membrane recognition of membrane-acting antimicrobial peptides]. | A number of antimicrobial peptides have been isolated in the animal kingdom, serving as defensive or offensive weapons. The mechanisms of their action are considered to be the permeability of bacterial membranes, although the details are not yet clarified. I have studied the interactions of several antibiotic peptides ... |
9188841 | Determination of piracetam in human plasma by capillary electrophoresis. | A capillary electrophoresis (CE) procedure has been developed for the determination of piracetam in human plasma. Analyses were performed on an uncoated silica capillary using borax buffer modified with the addition of alpha-cyclodextrin. The detection was UV, operated at 200 nm. The detection limit of the authentic sa... |
9188180 | Application of a beta-cyclodextrin sulfate-immobilized precolumn to selective on-line enrichment and separation of heparin-binding proteins by column-switching high-performance liquid chromatography. | A column-switching high-performance liquid chromatography (HPLC) system which consisted of a beta-cyclodextrin (beta-CD) sulfate-immobilized hydrophilic vinyl-polymer gel precolumn and a reversed-phase analytical column was developed for the selective on-line enrichment and separation of heparin-binding proteins. Of 15... |
9188178 | Preparative enantiomer separation of the inhalation anesthetics enflurane, isoflurane and desflurane by gas chromatography on a derivatized gamma-cyclodextrin stationary phase. | The preparative enantiomeric separation of the inhalation anesthetics enflurane (1) and isoflurane (2) in very high chemical (> 99.5%) and enantiomeric excess (ee > 99%) by gas chromatography (GC) on octakis(3-O-butanoyl-2,6-di-O-n-pentyl)-gamma-cyclodextrin (4), dissolved in the apolar polysiloxane SE-54 and coated on... |
9187252 | Efficient purification, characterization and partial amino acid sequencing of two alpha-1,4-glucan lyases from fungi. | alpha-1,4-Glucan lyases from the fungi Morchella costata and M. vulgaris were purified by affinity chromatography on beta-cyclodextrin-sepharose, followed by ion exchange and gel filtration. The purified enzymes produced 1,5-anhydro-D-fructose from glucose oligomers and polymers with alpha-1,4-glucosidic linkages, such... |
9184922 | External calcium-dependent, F-actin-independent and pertussis toxin-insensitive novel neutrophil locomotion induced by a mAb. | We previously demonstrated that a mAb to human neutrophils, designated 3H9, which was established by screening for inhibition of neutrophil adherence to plastic plates containing fetal bovine serum, enhanced both n-formyl-methionyl-leucyl-phenylalanine (FMLP)-induced chemotaxis and random migration of neutrophils. In t... |
9184804 | Pharmacokinetic profile of piroxicam beta-cyclodextrin, in rat plasma and lymph. | 1. The absorption of piroxicam into the blood of rats is significantly slower after oral administration of piroxicam beta-cyclodextrin than of free piroxicam. 2. The pharmacokinetic profiles of piroxicam in rat lymph were very similar in both groups. 3. Bioavailability of piroxicam in plasma is higher after treatment w... |
9184238 | Identification of structural elements critical for inter-domain interactions in a group II self-splicing intron. | Thus far, conventional biophysical techniques, such as NMR spectroscopy or X-ray crystallography, allow the determination, at atomic resolution, of only structural domains of large RNA molecules such as group I introns. Determination of their overall spatial organization thus still relies on modeling. This requires tha... |
9178557 | Purification of amylases and other enzymes by a forced-affinity chromatography method. | An affinity matrix of soluble starch gel was prepared by cross-linking catalyzed by epichlorohydrin. The elution pattern of Taka-amylase A (TAA) indicated that the amount of enzyme bound to the starch gel column increased with increases in the ammonium sulfate (AmS) concentration in the equilibrating buffer. TAA had an... |
9177680 | Long-lifetime metal-ligand pH probe. | We describe the synthesis and fluorescence spectral characterization of a pH-sensitive metal-ligand complex, [Ru(deabpy)(bpy)2]2., where deabpy is 4,4'-diethylaminomethyl-2,2'-bipyridine. This metal-ligand complex (MLC) was found to display pH-dependent intensities, emission spectra, and decay times, with the changes c... |
9174614 | Mimotopes of polyreactive anti-DNA antibodies identified using phage-display peptide libraries. | Three monoclonal IgG2a anti-DNA polyreactive autoantibodies, derived from lupus-prone mice (NZB x NZW)F1, were studied by surface plasmon resonance (BIAcore) analysis using three different synthetic double-stranded (ds) oligonucleotides of 25, 30, and 25 base pairs (bp). These monoclonal antibodies (mAb) exhibited diss... |
9174347 | Complex of plastocyanin and cytochrome c characterized by NMR chemical shift analysis. | The complexes of horse ferrous and ferric cytochrome c with Cd-substituted pea plastocyanin have been characterized by nuclear magnetic resonance, in order to determine the binding sites and to study the effects of complex formation. Reproducible, small chemical shift changes (0.005-0.05 ppm) were observed for protons ... |
9171360 | Structure of the chromatin binding (chromo) domain from mouse modifier protein 1. | The structure of a chromatin binding domain from mouse chromatin modifier protein 1 (MoMOD1) was determined using nuclear magnetic resonance (NMR) spectroscopy. The protein consists of an N-terminal three-stranded anti-parallel beta-sheet which folds against a C-terminal alpha-helix. The structure reveals an unexpected... |
9171287 | Recognition of tRNA(Gly) by three widely diverged glycyl-tRNA synthetases. | Glycyl-tRNA synthetase (GlyRS) is an unusual aminoacyl-tRNA synthetase because it varies in its quarternary structure between organisms; Escherichia coli GlyRS is an alpha2beta2 tetramer, whereas those of Thermus thermophilus and yeast are alpha2 dimers. In contrast, the tRNA(Gly) sequence is virtually identical in E. ... |
9168470 | pp60v-src transformation of rat cells but not chicken cells strongly correlates with low-affinity phosphopeptide binding by the SH2 domain. | Substrates critical for transformation by pp60v-src remain unknown, as does the precise role of the src homology 2 (SH2) domain in this process. To continue exploring the role of the SH2 domain in pp60v-src-mediated transformation, site-directed mutagenesis was used to create mutant v-src alleles predicted to encode pr... |
9168216 | Tramadol and beta-cyclodextrin piroxicam: effective multimodal balanced analgesia for the intra- and postoperative period. | <h4>Background and objectives</h4>This study was conducted to evaluate the analgesic efficacy of tramadol, an analgesic with both opioid and nonopioid actions (norepinephrine and serotonin pathways), with beta-cyclodextrin piroxicam, a nonsteroidal antiinflammatory drug, in the perioperative setting.<h4>Methods</h4>The... |
9167839 | Perfluoro-15-crown-5-ether labelled macrophages in adoptive transfer experimental allergic encephalomyelitis. | In this serial in vivo study, macrophages labelled with perfluoro-15-crown-5-ether (15C5) were monitored in rats after inducing adoptive transfer experimental allergic encephalomyelitis (AT-EAE). AT-EAE is an animal model of multiple sclerosis and is characterized by inflammatory infiltrates in the central nervous syst... |
9166770 | Solution structure of the actinorhodin polyketide synthase acyl carrier protein from Streptomyces coelicolor A3(2). | The solution structure of the actinorhodin acyl carrier protein (act apo-ACP) from the polyketide synthase (PKS) of Streptomyces coelicolor A3(2) has been determined using 1H NMR spectroscopy, representing the first polyketide synthase component for which detailed structural information has been obtained. Twenty-four s... |
9165535 | Confocal laser scanning microscopic visualization of the transport of dextrans after nasal administration to rats: effects of absorption enhancers. | <h4>Purpose</h4>To visualize the transport pathway(s) of high molecular weight model compounds across rat nasal epithelium in vivo using confocal laser scanning microscopy. Furthermore, the influence of nasal absorption enhancers (randomly methylated beta-cyclodextrin and sodium taurodihydrofusidate) on this transport ... |
9165524 | Cyclodextrins: their future in drug formulation and delivery. | Since their discovery, cyclodextrins and their ability to form inclusion complexes have fascinated chemists, formulators and recently, entrepreneurs. This mini-review has as its objective, a critical assessment of the current status of cyclodextrins in the formulation and delivery of pharmaceuticals and commentary on t... |
9159151 | Antigens produced in plants by infection with chimeric plant viruses immunize against rabies virus and HIV-1. | The coat protein (CP) of alfalfa mosaic virus was used as a carrier molecule to express antigenic peptides from rabies virus and HIV. The antigens were separately cloned into the reading frame of alfalfa mosaic virus CP and placed under the control of the subgenomic promoter of tobacco mosaic virus CP in the 30BRz vect... |
9159124 | Estimation of the DNA sequence discriminatory ability of hairpin-linked lexitropsins. | Three- and four-ring polyamides containing N-methylimidazole and N-methylpyrrole, and their hairpin-linked derivatives, bind side-by-side in the minor groove of DNA in a sequence-specific manner. The sequences recognized by side-by-side molecules are dependent on the pairings of the polyamide rings to the bases. In thi... |
9159490 | Dissecting the energetics of a protein-protein interaction: the binding of ovomucoid third domain to elastase. | An understanding of the structural basis for protein-protein interactions, and molecular recognition in general, requires complete characterization of binding energetics. Not only does this include quantification of the changes that occur in all of the thermodynamic parameters upon binding, including the enthalpy, entr... |
9154323 | Central antitussive activity of the NK1 and NK2 tachykinin receptor antagonists, CP-99,994 and SR 48968, in the guinea-pig and cat. | 1. The purpose of this study was to investigate the antitussive activity and sites of action of the NK1 and NK2 tachykinin receptor antagonists, CP-99,994, SR 48968, and the racemate of SR 48968, SR 48212A in the cat and guinea-pig. 2. Guinea-pigs were dosed subcutaneously (s.c.) with CP-99,994, SR 48212A or SR 48968 o... |
9153291 | Isoform switching of type IV collagen is developmentally arrested in X-linked Alport syndrome leading to increased susceptibility of renal basement membranes to endoproteolysis. | Normal glomerular capillaries filter plasma through a basement membrane (GBM) rich in alpha3(IV), alpha4(IV), and alpha5(IV) chains of type IV collagen. We now show that these latter isoforms are absent biochemically from the glomeruli in patients with X-linked Alport syndrome (XAS). Their GBM instead retain a fetal di... |
9153429 | Gly-Gly-containing triplets of low stability adjacent to a type III collagen epitope. | Collagens, in addition to their structural role in the extracellular matrix, possess a number of functional binding domains. In this study, the binding to collagen of a monoclonal antibody is used as a model to define the molecular features involved in triple-helix interactions with other proteins. Here we report the t... |
9151673 | Agrin binds to the nerve-muscle basal lamina via laminin. | Agrin is a heparan sulfate proteoglycan that is required for the formation and maintenance of neuromuscular junctions. During development, agrin is secreted from motor neurons to trigger the local aggregation of acetylcholine receptors (AChRs) and other proteins in the muscle fiber, which together compose the postsynap... |
9150231 | Cloning and characterization of the gene for amylosucrase from Neisseria polysaccharea: production of a linear alpha-1,4-glucan. | The gene for the amylosucrase from Neisseria polysaccharea (ATCC 43768) was cloned by use of a functional expression system in Escherichia coli XL1-Blue. The deduced amino acid sequence of the protein has homology to the sequences of the alpha-amylase class of enzymes, with the highest similarities being found to the s... |
9150215 | A role for Salmonella typhimurium cbiK in cobalamin (vitamin B12) and siroheme biosynthesis. | The role of cbiK, a gene found encoded within the Salmonella typhimurium cob operon, has been investigated by studying its in vivo function in Escherichia coli. First, it was found that cbiK is not required for cobalamin biosynthesis in the presence of a genomic cysG gene (encoding siroheme synthase) background. Second... |
9164875 | Effect of temperature on the secondary structure of beta-lactoglobulin at pH 6.7, as determined by CD and IR spectroscopy: a test of the molten globule hypothesis. | Previous CD measurements of changes in the conformation of beta-lactoglobulin at neutral pH as a function of temperature indicated the formation of a molten globule state above approx. 70 degrees C. New CD measurements are reported at temperatures up to 80 degrees C with an instrument on the Daresbury synchrotron radia... |
9145839 | Behavior of amphotericin B lipid complex in plasma in vitro and in the circulation of rats. | Amphotericin B lipid complex (ABLC) shows reduced toxicity relative to that of amphotericin B deoxycholate (AmB-d) while maintaining antifungal activity. Rat blood or plasma was spiked with ABLC in vitro. Released amphotericin B was separated from the parent material by centrifugation. At early times (0 to 15 min) most... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.