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11114301 | Membrane raft association of CD47 is necessary for actin polymerization and protein kinase C theta translocation in its synergistic activation of T cells. | CD47 is a ubiquitously expressed membrane protein with an extracellular Ig domain and a multiple membrane-spanning domain that can synergize with antigen to induce interleukin (IL)-2 secretion by T lymphocytes. Ligation of CD47 induced actin polymerization and increased protein kinase Ctheta (PKCtheta) association with... |
11113142 | Cholera toxin is found in detergent-insoluble rafts/domains at the cell surface of hippocampal neurons but is internalized via a raft-independent mechanism. | A number of studies have demonstrated that cholera toxin (CT) is found in detergent-insoluble, cholesterol-enriched domains (rafts) in various cells, including neurons. We now demonstrate that even though CT is associated with these domains at the cell surface of cultured hippocampal neurons, it is internalized via a r... |
11178270 | Multiple RNA-protein interactions in Drosophila dosage compensation. | From worms to humans, recognizing and modifying a specific chromosome is essential for dosage compensation, the mechanism by which equal X-linked gene expression in males and females is achieved. Recent molecular genetic and biochemical studies have provided new insights into how regulatory factors in Drosophila are re... |
29711895 | Stereochemical Assignment of the C21-C38 Portion of the Desertomycin/Oasomycin Class of Natural Products by Using Universal NMR Databases: Prediction. | Stereochemistry can be predicted: The stereoselective synthesis of the C21-C38 degradation product derived from oasomycins A and B has confirmed the stereochemistry predicted from a comparitive study of the NMR chemical shifts of the C21-C38 portion of the natural products with those obtained for its diastereomers. |
23696326 | Eosin molecules hosted into a dendrimer which carries thirty-two dansyl units in the periphery: a photophysical study. | A fourth generation POPAM dendrimer functionalized at the periphery with 32 dansyl groups (circles in the picture) can host up to six eosin dye molecules (black ovals) in two different sites (triangle, square). Efficient energy transfer processes from the dansyl to eosin molecules occur. The picture shows some characte... |
16037859 | Photodynamic therapy comes of age. | The concept underlying photodynamic therapy (PDT) is the use of light-absorbing molecules which, when delivered to target cells, and activated by irradiation with light of the appropriate wavelength, produce reactive oxygen species that cause cell death by apoptosis or necrosis. Classically, photodynamic agents have be... |
11169636 | Electron Spin Polarization and Time-Resolved Electron Paramagnetic Resonance: Applications to the Paradigms of Molecular and Supramolecular Photochemistry. | Most molecular and supramolecular organic photochemical reactions involve paramagnetic reactive intermediates (such as molecular triplet states, triplet radical pairs, and free radicals). In a number of cases these species are created with "anomalous" spin populations which are far from thermal equilibrium. Such parama... |
11150184 | Disulfide-strapped porphyrins for monolayer formation on gold | Porphyrins with a disulfide-containing strap have been prepared as an alternative to dithiols for self-assembled monolayer formation on gold surfaces. The strapped porphyrins have the advantage of greater air stability than their dithiol analogues. Cis and trans atropisomers of a strapped porphyrin were isolated. Gold ... |
11150179 | Self-assembly of polar functionalities using noncovalent platforms | Small peptide fragments functionalized with dimelamine units spontaneously form well-defined assemblies. The hydrogen-bond donating and accepting sites in the peptide units are perfectly compatible with the hydrogen-bond assembly motif and slightly stabilize the assembly via additional hydrogen-bond formation. |
11149855 | Recognition of amides by new rigid Calix | The synthesis of new hosts specifically designed for the recognition of amides, characterized by two binding regions: a rigid calix[4]arene cavity and a sidearm, inserted at its rim, able to form strong hydrogen bonds, is described. The binding abilities of the new receptors toward amides of general structure R(1)CONR(... |
11149826 | Phosphino carboxylic acid ester functionalized carbosilane dendrimers: nanoscale ligands for the Pd-catalyzed hydrovinylation reaction in a membrane reactor | Phosphino carboxylic acid ester terminated G(0) compounds Si(CH(2))(3)SiMe(2)(C(6)H(4)CH(2)OC(O)(CH(2))(n)()CH(2)PPh(2)(4) (9a and 9b; n = 1, 2) and the carbosilane dendrimers Si(CH(2))(3)Si((CH(2))(3)SiMe(2)(C(6)H(4)CH(2)OC(O)(CH(2))(n)()CH(2) PPh(2))(3)(4) (10a and 10b; n = 1, 2) have been prepared as hemilabile nano... |
11133410 | Bisphenol A and Dental Sealants: Olea's Response. | Comments on "Determination of bisphenol A and related aromatic compounds released from Bis-GMA-based composites and sealants by high performance liquid chromatography." by ulgar R, Olea-Serrano MF, Novillo-Fertrell A, Rivas A, Pazos P, Pedraza V, Navajas J-M, Olea N. Environ Health Perspect 108:21-27 (2000). |
11133407 | TCE Meta-Analyses: Wartenberg et al.'s Response. | Comments on Trichloroethylene and Cancer: Epidemiologic Evidence by Daniel Wartenberg, Daniel Reyner, and Cheryl Siegel Scott. Environ Health Perspect 108(suppl 2):161-176 (2000). |
11118991 | Conformational preferences and supramolecular aggregation in 2-nitrophenylthiolates: 2-nitrophenyl-beta-D-thiogalactopyranoside | In the title compound, C(12)H(15)NO(7)S, the molecular conformation shows a concerted disrotatory twist of the nitro group and the galactose fragment out of the plane of the aryl ring. The molecules are linked by O-H.O hydrogen bonds [O.O range 2.725 (2)-3.024 (2) A and O-H.O range 155-175 degrees ] to form a three-dim... |
11118976 | A donor-acceptor compound composed of a dinuclear zinc(II) complex of a robson macrocycle with 8-methylquinoline | A donor-acceptor compound, diaqua-1kappaO,2kappaO-[&mgr;-11, 23-dimethyl-3,7,15,19-tetraazatricyclo[19.3.1.1(9,13)]hexacosa-1(25), 2,7,9,11,13(26),14,19,21,23-decaene-25,26-diolato-1kappa(4)N(3),N(7), O(25),O(26):2kappa(4)N(15),N(19),O(25),O(26)]dizinc(II) diperchlorate bis(8-methylquinoline) ethanol disolvate, [Zn(2)(... |
11112625 | An EPR investigation of persistent radicals from the photolysis of p, p'-dialkyl-substituted phenyl benzyl ketones adsorbed on MFI zeolites | The photolysis of isomeric pairs of p,p'-dialkyl-substituted phenyl benzyl ketones adsorbed on MFI zeolites has been investigated by EPR spectroscopy. Photolysis produces persistent "benzoyl type" and "benzyl type" radicals. The dominant persistent radical produced by photolysis of any particular isomeric pair depends ... |
11101388 | A convergent synthesis of Hexahomotriazacalix | A new, convergent synthesis of hexahomotriazacalix[3]arenes 1a-e is described. The key transformation in this synthesis involves the coupling of the triamines 4a-d with 2, 6-bis(chloromethyl)-4-methylphenol 5 and results in the formation of the hexahomotriazacalix[3]arenes 1a-d in 90-95% yield. The triamines 4a-d were ... |
11101384 | New crown annelated tetrathiafulvalenes: synthesis, electrochemistry, self-assembly of thiol derivatives, and metal cation recognition | The synthesis of new S(2)O(4)-crown annelated tetrathiafulvalene (TTF) derivatives substituted with one terminal thiol group is described. Self-assembled monolayers (SAMs) of these compounds have been assembled on gold and platinum surfaces, the latter substrate giving improved quality films. SAMs of TTF derivative 16b... |
11101372 | Pyrrole-inverted isomer of 5,10,15,20-tetraaryl-21-selenaporphyrin | A novel 5,10,15,20-tetraaryl-21-selenaporphyrin isomer with an inverted pyrrole ring, i.e., 5,10,15, 20-tetraaryl-2-aza-21-carba-22-selenaporphyrin (SeC-TArPH) has been produced by a [3 + 1] condensation of 2, 5-bis(phenylhydroxymethyl)selenophene and 5,10-ditolyltripyrrin. The reaction yielded 5,20-diphenyl-10,15-bis(... |
11101365 | Complexation between tert-butyl ketones and beta-cyclodextrin. Structural study by NMR and MD simulations | A structural study (NMR and MD) of the complexation between tert-butyl ketones and beta-cyclodextrin has been performed. A priority order for the alkyl and phenyl groups composing the ketones has been determined based on association constants: Ph- > C(6)H(11)- = t-Bu- > Bu-, Pr-, Me-. Geometries for the complexes are p... |
11099975 | Crystal engineering in the gem-alkynol family; synthon repetitivity and topological similarity in diphenylethynylmethanols: structures that lack O-H.O hydrogen bonds | The structures of four para-substituted derivatives of diphenylethynylmethanol have been determined [ditolylethynylmethanol, di(4-chlorophenyl)ethynylmethanol, di(4-bromophenyl)ethynylmethanol and bis(4,4'-biphenylyl)ethynylmethanol]. The dimethyl, dichloro, dibromo and diphenyl compounds have been analysed using X-ray... |
11099974 | Crystal engineering in the gem-alkynol family: interplay between strong and weak interactions in structures of 2,3,5,6-tetrahalo | Structures of the title compounds are all mediated by strong cooperative arrangements of O-H.O hydrogen bonds, supported by a variety of weaker interactions which affect the type of O-H.O synthon that is formed. The tetrafluoro compound contains hexameric O-H.O synthons in a supramolecular chair conformation, together ... |
11099973 | Adducts of meso and racemic 5,5,7,12,12,14-hexamethyl-1,4,8, 11-tetraazacyclotetradecane with trigonally trisubstituted benzene carboxylic acids: supramolecular structures in one and two dimensions | The meso and racemic forms of 5,5,7,12,12,14-hexamethyl-1,4,8, 11-tetraazacyclotetradecane, C(16)H(36)N(4) (tet-a and tet-b, respectively), form adducts with trigonally trisubstituted benzene carboxylic acids; tet-a-3,5-dinitrobenzoic acid (1/2) (1), tet-a-5-hydroxyisophthalic acid-water (1/1/1) (3) and tet-b-5-hydroxy... |
11097767 | Osmotic Compressibility of Poly(propylene imine) Dendrimers in Deuterated Methanol. | The inverse osmotic compressibility of the poly(propylene imine) dendrimers in deuterated methanol has been measured as a function of concentration with small-angle neutron scattering. The experimental results reveal three different regimes. First, there is a dilute regime going up to a maximum in the inverse osmotic c... |
12938476 | [FTIR studies of oxalate-bridged Gd(III)-Cr(III) hexanuclear bimetallic complex]. | The compound [Gd2(mu-ox)[Cr(bipy)(mu-ox)(ox)]4(H2O)6].13H2O (1) has been prepared by the self-assembly reaction of [Cr(bipy)(ox)2]- building blocks with Gd(III) ions. In this paper, we report the FTIR investigation of the compound(1). |
12938463 | [Infrared study on molecular structure and orientation in Langmuir-Blodgett films of chiral LCs M1]. | The LB films of chiral LCs M1 were investigated by FTIR transmission and reflection absorption spectra. CaF2 and vacuum deposition gold plate were used as solid substrate. The LB films can be transferred onto the solid substrate successfully. The orientation of LB films was analysis by comparing the FTIR transmission a... |
12938460 | [The molecular structure and the arrangement changes of stilbazoles in the phase transition process studied by temperature-variable FTIR spectroscopy]. | Hydrogen bonding is one of the principal intermolecular forces to enable the construction of supramolecular structures. By choosing an appropriate proton acceptor and a proton donor, stable intermolecular hydrogen bonds can form and affect or change the phase behavior of the donor and acceptor. We have obtained two int... |
12575272 | [Study on the technological process of including volatile oil of Baizhu with beta-cyclodextrin]. | The volatile oil of Baizhu was included with beta-CD. The factors affecting the formation of the inclusion compounds were researched by L9(3(4)) orthogonal test. The ratio of the oil in inclusion compounds and recovery of inclusion compounds were used as criteria in the test. The best conditions for inclusion were A2B3... |
11426690 | Common properties of fusion peptides from diverse systems. | Although membrane fusion occurs ubiquitously and continuously in all eukaroytic cells, little is known about the mechanism that governs lipid bilayer fusion associated with any intracellular fusion reactions. Recent studies of the fusion of enveloped viruses with host cell membranes have helped to define the fusion pro... |
11312777 | Constituents and their sweetness of food additive enzymatically modified licorice extract. | Enzymatically modified licorice extract (EMLE) is a natural sweetener, which is prepared with cyclodextrin glucanotransferase. It is used because of its unique properties such as higher solubility and better taste than those of licorice extract. In the present paper, the structures of six major constituents isolated fr... |
11312776 | Stereochemical composition of clenbuterol residues in edible tissues of swine. | A gas chromatography-mass spectrometry method was developed to measure the stereochemical residues of clenbuterol derivatives in edible tissues of swine. Clenbuterol present in tissue extracts was derivatized with phosgene to form clenbuterol oxazolidin-3-one, which was then separated into component enantiomers using a... |
11299487 | [Multiple organ failure in experimental pancreatitis]. | <h4>Background</h4>Multiple organ failure (MOF) is the most severe complication and the most frequent cause of death in acute necrotizing pancreatitis (ANP).<h4>Objective</h4>To evaluate the components and the time course of MOF in an experimental model of ANP.<h4>Method</h4>Induction of ANP in rats by a standardised b... |
11276314 | Effect of tetrapeptide cortagen on regeneration of sciatic nerve. | Intramuscular injection of 10 microg/kg cortagen to rats during 10 days after transsection and suturing of the sciatic nerve increased the growth rate and conduction velocity in the regenerating nerve fibers by 27% and 40%, respectively. |
11269923 | Peptide immunoreactivity and ultrastructure of rat urinary bladder nerve fibers after topical desensitization by capsaicin or resiniferatoxin. | In the present study the decrease of neuropeptide containing nerve fibers and the increase in the volume threshold to reflex micturition occurring in the rat bladder after intravesical application of capsaicin or resiniferatoxin were compared. The ultrastructure of bladder terminal axons was evaluated at the moment of ... |
11243888 | Enamel biomineralization defects result from alterations to amelogenin self-assembly. | Enamel formation is a powerful model for the study of biomineralization. A key feature common to all biomineralizing systems is their dependency upon the biosynthesis of an extracellular organic matrix that is competent to direct the formation of the subsequent mineral phase. The major organic component of forming mous... |
11272339 | A calix[4]arene based calcium-selective optode membrane: measuring the absorbance maximum wavelength shift. | An absorbance based calcium ion sensor is presented which applies a new immobilized chromogenic calix[4]arene. The membrane consists of a hydrogel/1,3-pentanedial mixture and the 1,3-bis(indoaniline)-derived 2,4-bis-[(ethylcarbonyl)methoxyl-calix[4]arene as calcium receptor. The indicator entrapped within the gel was n... |
11164457 | Zinc, infections and immunosenescence. | Infections may cause mortality in old age due to damaged immune responses. As zinc is required as a catalyst, structural (zinc fingers) and regulatory ion, it is involved in many biological functions, including immune responses. Low zinc ion bioavailability and impaired cell-mediated immunity are common in ageing and m... |
11167751 | Defibrotide for the treatment of hepatic veno-occlusive disease: results of the European compassionate-use study. | Severe hepatic veno-occlusive disease (VOD) is a recognized complication of autologous and allogeneic stem cell transplantation (SCT) that is often fatal. Defibrotide (DF) is a polydeoxyribonucleotide that has been found to have anti-thrombotic, anti-ischaemic and thrombolytic properties without causing significant ant... |
11215522 | Protein surface similarities: a survey of methods to describe and compare protein surfaces. | Many methods have been developed to analyse protein sequences and structures, although less work has been undertaken describing and comparing protein surfaces. Evolution can lead sequences to diverge or structures to change topology; nevertheless, surface determinants that are essential to protein function itself may b... |
11215517 | Ferrochelatase at the millennium: structures, mechanisms and [2Fe-2S] clusters. | Ferrochelatase (E.C. 4.99.1.1, protoheme ferrolyase) catalyzes the insertion of ferrous iron into protoporphyrin IX to form protoheme (heme). In the past 2 years, the crystal structures of ferrochelatases from the bacterium Bacillus subtilis and human have been determined. These structures along with years of biophysic... |
11215515 | Biosynthesis of cobalamin (vitamin B12): a bacterial conundrum. | The biosynthesis of cobalamin (vitamin B12) is described, revealing how the concerted action of around 30 enzyme-mediated steps results in the synthesis of one of Nature's most structurally complex 'small molecules'. The plethora of genome sequences has meant that bacteria capable of cobalamin synthesis can be easily i... |
11210138 | Analysis of catalytic residues of Thermoactinomyces vulgaris R-47 alpha-amylase II (TVA II) by site-directed mutagenesis. | To confirm that the catalytic residues (Asp325, Glu354, and Asp421) are necessary for the hydrolysis of starch, pullulan, and cyclodextrins, we constructed TVA II mutated by site-directed mutagenesis. The mutated enzymes (D325N, E354Q, and D421N) had markedly reduced levels of activity, less than 0.006% of the wild typ... |
11206076 | N-terminal mutations in the anti-estradiol Fab 57-2 modify its hapten binding properties. | Recombinant antibodies often contain N-terminal mutations arising from the use of degenerate cloning primer sets and/or the introduction of restriction sites in the framework 1 regions. We studied the effects of such mutations in a recombinant anti-estradiol Fab fragment derived from the hybridoma cell line 57-2. The 5... |
11206075 | Ab initio molecular dynamics studies on HIV-1 reverse transcriptase triphosphate binding site: implications for nucleoside-analog drug resistance. | Quantum-chemical methods are used to shed light on the functional role of residues involved in the resistance of HIV-1 reverse transcriptase against nucleoside-analog drugs. Ab initio molecular dynamics simulations are carried out for models representing the adduct between the triphosphate substrate and the nucleoside ... |
11206071 | Characterization of the interface structure of enzyme-inhibitor complex by using hydrogen-deuterium exchange and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. | We investigated the interaction between a thiol protease inhibitor, cystatin, and its target enzyme, papain, by hydrogen-deuterium (H/D) exchange in conjunction with successive analysis by collision-induced dissociation (CID) in an rf-only hexapole ion guide with electrospray ionization-Fourier transform ion cyclotron ... |
11206062 | Chaperonin-assisted folding of glutamine synthetase under nonpermissive conditions: off-pathway aggregation propensity does not determine the co-chaperonin requirement. | One of the proposed roles of the GroEL-GroES cavity is to provide an "infinite dilution" folding chamber where protein substrate can fold avoiding deleterious off-pathway aggregation. Support for this hypothesis has been strengthened by a number of studies that demonstrated a mandatory GroES requirement under nonpermis... |
11206059 | Stability and peptide binding specificity of Btk SH2 domain: molecular basis for X-linked agammaglobulinemia. | X-linked agammaglobulinemia (XLA) is caused by mutations in the Bruton's tyrosine kinase (Btk). The absence of functional Btk leads to failure of B-cell development that incapacitates antibody production in XLA patients leading to recurrent bacterial infections. Btk SH2 domain is essential for phospholipase C-gamma pho... |
11206058 | Evolution of binding affinity in a WW domain probed by phage display. | The WW domain is an approximately 38 residue peptide-binding motif that binds a variety of sequences, including the consensus sequence xPPxY. We have displayed hYAP65 WW on the surface of M13 phage and randomized one-third of its three-stranded antiparallel beta-sheet. Improved binding to the hydrophobic peptide, GTPPP... |
11206052 | Automated search of natively folded protein fragments for high-throughput structure determination in structural genomics. | Structural genomic projects envision almost routine protein structure determinations, which are currently imaginable only for small proteins with molecular weights below 25,000 Da. For larger proteins, structural insight can be obtained by breaking them into small segments of amino acid sequences that can fold into nat... |
11206051 | Cysteine-independent polymerization of metallothioneins in solutions and in crystals. | Polymerization of metallothioneins is one of the usually encountered puzzles during the research process of metallothioneins' structure and function. Our work focuses on the cysteine independently occurred polymerization from metallothioneins monomers in different milieus, while it leaves out the aggregation caused by ... |
11206050 | Design of a minimal protein oligomerization domain by a structural approach. | Because of the simplicity and regularity of the alpha-helical coiled coil relative to other structural motifs, it can be conveniently used to clarify the molecular interactions responsible for protein folding and stability. Here we describe the de novo design and characterization of a two heptad-repeat peptide stabiliz... |
11150611 | Glucoamylase: structure/function relationships, and protein engineering. | Glucoamylases are inverting exo-acting starch hydrolases releasing beta-glucose from the non-reducing ends of starch and related substrates. The majority of glucoamylases are multidomain enzymes consisting of a catalytic domain connected to a starch-binding domain by an O-glycosylated linker region. Three-dimensional s... |
11141437 | [Acute renal failure profile and prognostic value in severe acute pancreatitis]. | <h4>Background</h4>Acute renal failure (ARF) complicating severe acute pancreatitis (SAP) carries a high mortality. Clinically useful scores to define patients who will develop this complication are lacking. We try to determine the incidence of ARF and variables predicting the appearance and severity of the episodes.<h... |
11121892 | Effect of cyclodextrin-encapsulated beta-carotene on progesterone production by bovine luteal cells. | Experiments were conducted to examine the effect of cyclodextrin-encapsulated beta-carotene on basal or cholesterol (cyclodextrin-encapsulated), LH and dibutyryl cyclic AMP (dbcAMP)-stimulated progesterone production by bovine corpus luteum cells isolated from mid-luteal heifer ovaries by collagenase digestion. Cells w... |
11198931 | Downregulation of the p75 neurotrophin receptor in tissue culture and in vivo, using beta-cyclodextrin-adamantane-oligonucleotide conjugates. | Formation of complexes with beta-cyclodextrin derivatives via adamantyl groups was found to enhance the uptake and antisense efficacy of phosphorothioate oligos targeted to the p75 neurotrophin receptor in neuronally differentiated PC12 cells. After a 2-week course of systemic administration to mice (by intraperitoneal... |
11192939 | Selective inhibition of arachidonic acid epoxidation in vivo. | Cytochrome P450 (CYP)-derived arachidonic acid metabolites, including epoxyeicosatrienoic acids (EETS) and 20-HETE, have been implicated in the regulation of renal function and vascular tone. Studying the function of specific CYP arachidonate metabolites has been hampered due to lack of selective inhibitors and difficu... |
11192170 | Separation ability and stoichiometry of cyclodextrin complexes. | Gas-liquid chromatography has been applied to search relations between selectivity towards isomers and stoichiometry of cyclodextrin complexes. The model tested compounds were: dimethylnaphthalenes and alpha- and beta-pinenes as constitutional isomers; cis/trans decalins, anetholes and isosafroles as diastereomers and ... |
11192097 | The synthesis and glass-forming properties of phthalocyanine-containing poly(aryl ether) dendrimers. | The synthesis, structural characterisation and properties of a number of phthalocyanine-containing dendrimers are described. Peripheral substitution of phthalocyanine (Pc) with four poly(aryl ether) dendritic wedges (1st, 2nd or 3rd generation) produces materials whose properties are dominated both by the columnar self... |
11192127 | Recent progress in chiral separation principles in capillary electrophoresis. | This review summarizes recent developments in the field of chiral separations by electromigration techniques including capillary zone electrophoresis (CZE), capillary gel electrophoresis (CGE), isotachophoresis (ITP), electrokinetic chromatography (EKC), and capillary electrochromatography (CEC). This overview focuses ... |
11163991 | Examination of the biophysical interaction between plasmid DNA and the polycations, polylysine and polyornithine, as a basis for their differential gene transfection in-vitro. | The impetus to develop non-viral gene delivery vectors has led to examination of synthetic polycationic polymers as plasmid DNA (pDNA) condensing agents. Previous reports have highlighted superiority (up to x 10-fold) in the in-vitro transfection of pDNA complexes formed by poly-(L)-ornithine (PLO) compared to those fo... |
11153948 | Development and evaluation of a linear regression method for the prediction of maximal chiral separation of basic drug racemates by cyclodextrin-mediated capillary zone electrophoresis. | An important step in method development of chiral separations with neutral cyclodextrins (CDs) as chiral selectors is the estimation of the CD concentration that gives the highest degree of separation. From the equation [S]opt=1/(K1K2)(1/2) this optimal CD concentration can be calculated if any knowledge is available a... |
11153946 | Micellar electrokinetic chromatography of polychlorinated biphenyl congeners using a polymeric surfactant as the pseudostationary phase. | Micellar electrokinetic chromatography (MEKC) of highly hydrophobic compounds is generally difficult using sodium dodecyl sulfate micellar solutions. The polymeric surfactant, polysodium undecyl sulfate (poly-SUS) has been used to separate moderately to highly hydrophobic polychlorinated biphenyl (PCB) congeners by MEK... |
11153956 | Chromatographic study of terpene derivatives on porous graphitic carbon stationary phase with beta-cyclodextrin as mobile phase modifier. | The stoichiometric coefficients and apparent formation constants (Kf) of alpha-terpineol, thymol, geraniol and linalool complexes with beta-cyclodextrin (beta-CD) were determined using HPLC with a porous graphitic carbon (PGC) chromatographic support. Measurements were performed with four different methanol-water mobil... |
11153955 | Characterization of inclusion complexes of betamethasone-related steroids with cyclodextrins using high-performance liquid chromatography. | HPLC was used to study the inclusion complexes formed between various beta- and gamma-cyclodextrins and a series of corticosteroids related to betamethasone. Apparent association constants were measured in acetonitrile-water for a set of 13 steroids. An increase in the stability of the steroid-cyclodextrin complex is o... |
11151379 | Self-assembly of a diferrous triple-stranded helicate with bis(2,2'-bipyridine) ligands: thermodynamic and kinetic intermediates. | The protonation and iron(II) coordination properties of a bis(2,2'-bipyridine) ligand L were investigated in methanol. The protonated forms showed allosteric effects due to the flexibility of the strand. Speciation studies of the corresponding ferrous complexes were carried out as a function of pH and iron(II) concentr... |
11151367 | Corroles with group 15 ions. 2. Synthesis and characterization of octaethylcorroles containing a phosphorus central atom. | The synthesis, spectroscopic characterization, and electrochemistry of five new phosphorus corroles are reported. The investigated complexes contain alkyl, aryl, oxo, or hydrido axial ligands and are represented as (OEC)P(H)2, (OEC)P(CH3)2, (OEC)P(C6H5)2, (OEC)P=O, and [(OEC)P(CH3)]+ClO4-, where OEC is the trianion of ... |
11147128 | Liposomes containing drug and cyclodextrin prepared by the one-step spray-drying method. | The one-step spray-drying method was applied in the preparation of liposomes containing drug and cyclodextrin (CD). Spray-dried lecithin liposomes, entrapping metronidazole or verapamil alone or together with hydroxypropyl-beta-cyclodextrin (HP beta CD), were characterized for morphology, size distribution, and drug en... |
11147126 | Direct compression tablets containing a series of four beta-cyclodextrin complexes formed by neutralizing an acidic drug. | A series of four beta-cyclodextrin complexes (called products) was formed by neutralizing an acidic drug to study the effect of drug solubility on complex formation and the dissolution performance from direct compression tablets. Four solid products were prepared by neutralizing the drug in 0.05, 0.10, 0.20, and 0.30 M... |
11147103 | Genomics and medicine: an anticipation. From Boolean Mendelian genetics to multifactorial molecular medicine. | The major impact of the completion of the human genome sequence will be the understanding of diseases, with deduced therapy. In the field of genetic disorders, we will complete the catalogue of monogenic diseases, also called Mendelian diseases because they obey the Boolean logic of Mendel's laws. The major challenge n... |
11147841 | Structural basis for recognition of dipeptides by peptide transporters. | Our objective in this work was to identify the structural basis for the molecular recognition of peptides by peptide transporters. Various assays for dipeptide transport by the dipeptide and tripeptide permeases of Escherichia coli were performed, together with measurements of thermodynamic parameters of substrate bind... |
11142163 | [Recent advances is surgical adjuvant chemotherapy for colorectal cancer]. | To evaluate the significance of surgical adjuvant chemotherapy, randomized controlled trials (RCTs) of adjuvant chemotherapy after curative resection for colorectal cancer were reviewed. Several multi-drug systemic chemotherapies (MOF, MMC/FT, 5-FU, UFT p.o.) were useful as adjuvant treatment to improve survival or dis... |
11140259 | Photomodulated azoaldolase: a model for light intervention in biological systems? | Azoaldolase is obtained from rabbit muscle aldolase by adding an azo chromophore to a cysteine side chain in each of the four enzyme subunits. The enzyme becomes photosensitive whereas both its catalytic activity and the michaelian kinetics are retained. Chromophore excitation causes E to Z isomerization of the azo bon... |
11140958 | Sulfone-linked paracyclophanes via macrocyclic aromatic thioethers: synthetic and structural investigations. | Reaction of 4,4'-sulfonylbis(benzenethiol) with 4,4'-dichlorodiphenylsulfone under pseudo-high-dilution conditions leads to macrocyclic thioethersulfones [-S-Ar-SO2-Ar-]n (Ar = 1,4-phenylene). These include a highly strained [1+1] cyclodimer (n = 2), a cyclotrimer resulting from thioetherexchange reactions, and a [2+2]... |
11140637 | Structural basis for binding of Smac/DIABLO to the XIAP BIR3 domain. | The inhibitor-of-apoptosis proteins (IAPs) regulate programmed cell death by inhibiting members of the caspase family of enzymes. Recently, a mammalian protein called Smac (also named DIABLO) was identified that binds to the IAPs and promotes caspase activation. Although undefined in the X-ray structure, the amino-term... |
11140538 | Bicycloalternarenes produced by the phytopathogenic fungus Alternaria alternata. | Eleven compounds, ACTG toxins A and B and nine new substances named bicycloalternarenes (BCAs), were isolated and characterized from the culture filtrate of the phytopathogenic fungus Alternaria alternata. Under acidic conditions, these mixed terpenoids convert to pairs of tricycloaltenarenes that can be used for ident... |
11145155 | Complex formation of cyclomaltononaose delta-cyclodextrin (delta-CD) with macrocyclic compounds. | The complex forming ability of delta-cyclodextrin delta-CD with 7 kinds of macrocyclic compounds (MCCs) with 8-15 carbon atoms in the ring as models of large guest molecules was studied in aqueous solution and compared with the complexation properties of alpha-, beta- and gamma-CD. Both alpha- and beta-CD formed relati... |
11145057 | Determination of immunoreactive gonadotropin-releasing hormone in serum and urine by on-line immunoaffinity capillary electrophoresis coupled to mass spectrometry. | The need for urgent diagnoses has propelled the development of automated analyses that can be performed in a short time at reasonable cost. One such method is immunoaffinity capillary electrophoresis. This emerging hybrid technology employs two powerful techniques coupled on-line for the direct and rapid determination ... |
11145345 | Theoretical study of the structure and vibrational spectra of the Ci(2) conformation of 18-crown-6. | Optimized geometries of 18-crown-6 (18ce6) were calculated at the HF/6-31G* and B3LYP/6-31G* levels of theory for the D3d, Ci(1) and Ci(2) conformations. At the B3LYP level, the Ci(2) optimized geometry was higher in energy by 23.3 and 18.8 kcal mol(-1) than the Ci(1) and D3d optimized geometries, respectively. Harmoni... |
11145343 | Studies of solvation of ketocyanine dyes in homogeneous and heterogeneous media by UV/Vis spectroscopic method. | Solvation characteristics of ketocyanine dyes (I-VI) have been investigated in pure solvents and heterogeneous media by absorption and fluorescence studies. The dyes are good reporters of solvent polarity. In protic solvents they exist as equilibrium mixtures of bare and hydrogen-bonded form in the ground state (S0), t... |
11125818 | Introduction of monosaccharides having functional groups onto a carbosilane dendrimer: a broadly applicable one-pot reaction in liquid ammonia involving Birch reduction and subsequent SN2 reaction. | Benzylthioalkyl glycosides of D-glucuronic acid, N-acetyl-D-glucosamine, and N-acetylneuraminic acid (common monosaccharide constituents of natural oligosaccharide chains) have been prepared as sulfide precursors for the carbohydrate coating of dendric carbosilane cores and used in a generally applicable one-pot reacti... |
11131906 | A debate on the subject "Are SIRS and MODS important entities in the clinical evaluation of patients?" The con position. | SIRS, MODS, and MOF are not diseases or even syndromes. They are simply clinical descriptors of people that are sick. They are symptoms and signs of various stages of illness progressing to death in the modern organ supporting ICU. They are catchy, popular acronyms but they cannot be treated specifically, and then only... |
11128945 | Selective potassium ion recognition by benzo-15-crown-5 fluoroionophore/gamma-cyclodextrin complex sensors in water. | Three fluoroionophores Cn (n = 1, 3, 5), in which the crown ether unit and pyrenyl moiety are connected by a -(CH2)n- spacer, have been used to construct supramolecular Cn/gamma-cyclodextrin (gamma-CyD) complexes for alkali metal ion sensing in water. The Cn (n = 3, 5) are found to selectively form 2:1 complexes with K... |
11149845 | Synthesis, characterization, and supramolecular properties of a hydrophilic porphyrin--beta-cyclodextrin conjugate. | Reductive amination of 6-deoxy-6-formyl-beta-cyclodextrin with 5-(p-aminophenyl)-10,15,20-tris(p-sulfonatophenyl)porphyrin in the presence of an excess of sodium cyanoborohydride affords the hydrophilic cyclodextrin-porphyrin conjugate 3 in 23% yield. The structure of 3 was confirmed by NMR spectroscopy and mass spectr... |
11148378 | [Biopharmaceutics of local anesthetic-cyclodextrin complexes following loco-regional administration]. | In the research of new dosage forms improving the therapeutic index of local anesthetics, we studied cyclodextrins, cyclic oligosaccharides forming soluble inclusion complexes with various lipophilic drugs. Complexes between bupivacaine and hydroxypropyl-B-cyclodextrin, bupivacaine and sulfobutyl ether-7-B-cyclodextrin... |
11139457 | Characterization of [(3)H]-CGP54626A binding to heterodimeric GABA(B) receptors stably expressed in mammalian cells. | Functional human GABA(B(1a,2)) and GABA(B(1b,2)) receptors have been stably expressed in mammalian CHO K1 cells. Detailed characterization of GABA(B) ligand binding at each of the receptors has been compared using [(3)H]-CGP54626A. In cell membranes fractions, [(3)H]-CGP54626A bound to a single site with a K(D) of 1. 5... |
11137335 | Cross-linked beta-cyclodextrin microcapsules: preparation and properties. | Microcapsules were prepared by interfacial cross-linking of beta-cyclodextrins (beta-CD) with terephthaloyl chloride (TC). Batches were prepared from beta-CD solutions in 1 M NaOH, using 5% TC and a 30 min reaction time. Microcapsules were studied with respect to morphology (microscopy), size (laser diffraction techniq... |
11137814 | Mechanisms of molecular recognition in the pikromycin polyketide synthase. | <h4>Background</h4>Modular polyketide synthases (PKSs) produce a wide range of medically significant compounds. In the case of the pikromycin PKS of Streptomyces venezuelae, four separate polypeptides (PikAI-PikAIV), comprising a total of one loading domain and six extension modules, generate the 14-membered ring macro... |
11136976 | DNA-PKcs is required for activation of innate immunity by immunostimulatory DNA. | Bacterial DNA and related synthetic immunostimulatory oligodeoxyribonucleotides (ISS-ODN) stimulate innate immunity. However, the molecular recognition mechanism that initiates signaling in response to bacterial DNA and ISS-ODN has not been identified. Herein, we demonstrate that administration of bacterial DNA and ISS... |
11136293 | Population PK and PK/PD modelling of microencapsulated octreotide acetate in healthy subjects. | <h4>Aims</h4>To develop a population model that can describe the pharmacokinetic profile of microencapsulated octreotide acetate in healthy cholecystectomized subjects. To investigate the correlation between serum IGF-1 and octreotide concentration.<h4>Methods</h4>A population pharmacokinetic analysis was performed on ... |
11133242 | Investigation of protein-protein interactions within flagellar dynein using homobifunctional and zero-length crosslinking reagents. | The dynein molecular motor is a highly complex enzyme containing up to 15 different protein components and consists of several distinct domains identifiable by electron microscopy. One of the current challenges is to understand the supramolecular organization of this motor and to determine the location and function of ... |
11134077 | Flightin is essential for thick filament assembly and sarcomere stability in Drosophila flight muscles. | Flightin is a multiply phosphorylated, 20-kD myofibrillar protein found in Drosophila indirect flight muscles (IFM). Previous work suggests that flightin plays an essential, as yet undefined, role in normal sarcomere structure and contractile activity. Here we show that flightin is associated with thick filaments where... |
11006286 | Differential targeting of beta -adrenergic receptor subtypes and adenylyl cyclase to cardiomyocyte caveolae. A mechanism to functionally regulate the cAMP signaling pathway. | Differential modes for beta(1)- and beta(2)-adrenergic receptor (AR) regulation of adenylyl cyclase in cardiomyocytes is most consistent with spatial regulation in microdomains of the plasma membrane. This study examines whether caveolae represent specialized subdomains that concentrate and organize these moieties in c... |
11124061 | DNA/dendrimer complexes mediate gene transfer into murine cardiac transplants ex vivo. | Starburst polyamidoamine dendrimers are synthetic polymers with unique structural and physical characteristics suitable for DNA gene transfer. Our previous studies demonstrated that Starburst dendrimers augment plasmid-mediated gene transfer efficiency in a nonvascularized, cardiac transplantation model. In this study,... |
11124039 | pH-dependent self-association of influenza hemagglutinin fusion peptides in lipid bilayers. | We have recently designed a host-guest peptide system that allows us to quantitatively measure the energetics of interaction of viral fusion peptides with lipid bilayers. Here, we show that fusion peptides of influenza hemagglutinin reversibly associate with one another at membrane surfaces above critical surface conce... |
11124029 | Multiple disordered loops function in corepressor-induced dimerization of the biotin repressor. | Cooperative association of the Escherichia coli biotin repressor with the biotin operator is allosterically activated by binding of the corepressor, bio-5'-AMP. The corepressor function of the adenylate is due, in part, to its ability to induce repressor dimerization. Since a high-resolution structure of only the apo o... |
11123921 | The asparagine-stabilized beta-turn of apamin: contribution to structural stability from dynamics simulation and amide hydrogen exchange analysis. | Molecular dynamics simulations of bee venom apamin, and an analogue having an Asn to Ala substitution at residue 2 (apamin-N2A), were analyzed to explore the contribution of hydrogen bonds involving Asn2 to local (beta-turn residues N2, C3, K4, A5) and global stability. The wild-type peptide retained a stable conformat... |
11123911 | Peptide-membrane interactions studied by a new phospholipid/polydiacetylene colorimetric vesicle assay. | Interactions between peptides and lipid membranes play major roles in numerous physiological processes, such as signaling, cytolysis, formation of ion channels, and cellular recognition. We describe a new colorimetric technique for studying peptide-membrane interactions. The new assay is based on supramolecular assembl... |
11121478 | Misincorporation of 2'-deoxyoxanosine into DNA: a molecular basis for NO-induced mutagenesis derived from theoretical calculations. | A wide range of theoretical methods, including high level ab initio, density functional, self-consistent reaction field, molecular dynamics and thermodynamic integration calculations, have been used to analyze the mutagenic properties of oxanosine. The major tautomeric forms in the gas phase and aqueous solution have b... |
11120819 | The physical association of protein kinase C theta with a lipid raft-associated inhibitor of kappa B factor kinase (IKK) complex plays a role in the activation of the NF-kappa B cascade by TCR and CD28. | We investigated the role of protein kinase C theta (PKCtheta) in the activation of the NF-kappaB cascade in primary human CD4(+) lymphocytes. Among six or so PKC isoforms expressed in T cells, only PKCtheta participates in the assembly of the supramolecular activation clusters at the contact site of the TCR with Ag. Si... |
11121077 | Highly specific, membrane-permeant peptide blockers of cGMP-dependent protein kinase Ialpha inhibit NO-induced cerebral dilation. | Arrays of octameric peptide libraries on cellulose paper were screened by using (32)P-autophosphorylated cGMP-dependent protein kinase Ialpha (cGPK) to identify peptide sequences with high binding affinity for cGPK. Iterative deconvolution of every amino acid position in the peptides identified the sequence LRK(5)H (W4... |
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