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12517150 | Stability of cyclic beta-hairpins: asymmetric contributions from side chains of a hydrogen-bonded cross-strand residue pair. | Amino acid structural propensities measured in "host-guest" model studies are often used in protein structure prediction or to choose appropriate residues in de novo protein design. While this concept has proven useful for helical structures, it is more difficult to apply successfully to beta-sheets. We have developed ... |
12517139 | Metal assembly in novel dendrimers with porphyrin cores. | A series of phenylazozmethine (DPA) dendrimers with a porphyrin core (PnH2) were synthesized by dehydration using TiCl4 from meso-tetrakis(4-aminophenyl)porphyrin and the DPA dendrons. The addition of SnCl2 to a dichloromethane/acetonitrile solution of dendritic cobalt porphyrin resulted in a stepwise spectral change. ... |
12517137 | Layer-by-layer growth of metal-metal bonded supramolecular thin films and its use in the fabrication of lateral nanoscale devices. | Layer-by-layer self-assembly of metal-metal bonded supramolecules is demonstrated and utilized to fabricate lateral nanoelectronic devices. Mercaptoethylpyridine is used to bind to Au substrates and to template the sequential assembly of alternating layers of redox active dirhodium complexes [Rh2(DAniF)2]2(O2CCH2CO2)2 ... |
12517133 | Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles. | Silver nanoparticles coated with a self-assembled layer of approximately 2500 chromophoric alkylthiol ligands, that exhibit a huge per particle two-photon absorption cross section (2.7 x 10-45 cm4 s photon-1) and a high fluorescence quantum yield (0.33), are reported. Polyfunctionalized variants of these nanoparticles ... |
12517111 | Biogenetic studies in Syringa vulgaris L.: synthesis and bioconversion of deuterium-labeled precursors into lilac aldehydes and lilac alcohols. | Syringa vulgaris L. inflorescences were fed with aqueous solutions of regioselectively deuterated compounds assumed to be precursors of lilac aldehyde and lilac alcohol, respectively. Volatiles were extracted by stir bar sorptive extraction (SBSE) and analyzed using enantioselective multidimensional gas chromatography/... |
12516052 | Optimisation of dendrimer-mediated gene transfer by anionic oligomers. | <h4>Background</h4>The application of synthetic vectors for gene transfer has potential advantages over virus-based systems. Their use, however, is limited since they generally lack the efficiency of gene transfer achieved with recombinant viral vectors such as adenovirus. Polyamidoamine (PAMAM) and phosphorus-containi... |
12516051 | Interaction of bronchoalveolar lavage fluid with polyplexes and lipoplexes: analysing the role of proteins and glycoproteins. | <h4>Background</h4>Plasmid DNA complexed with cationic lipids (lipoplexes) or cationic polymers (polyplexes) has been used for gene transfer into the lung. Topical gene administration of lipoplexes or polyplexes into the lung after intratracheal instillation or aerosolisation could cause interaction of the complexes wi... |
12515815 | Natural killer cell inhibitory receptors block actin cytoskeleton-dependent recruitment of 2B4 (CD244) to lipid rafts. | A dynamic balance of positive and negative signals regulates target cell lysis by natural killer (NK) cells upon engagement of a variety of different activation receptors and of inhibitory receptors that recruit the tyrosine phosphatase SHP-1. However, the step at which activation signals are blocked by SHP-1 is not kn... |
12515510 | Monolayer assemblies of a de novo designed 4-alpha-helix bundle carboprotein and its sulfur anchor fragment on Au(111) surfaces addressed by voltammetry and in situ scanning tunneling microscopy. | Mapping and control of proteins and oligonucleotides on metallic and nonmetallic surfaces are important in many respects. Electrochemical techniques based on single-crystal electrodes and scanning probe microscopies directly in aqueous solution (in situ SPM) have recently opened perspectives for such mapping at a resol... |
12515495 | Remarkably large positive and negative allosteric effects on ion recognition by the formation of a novel helical pseudocryptand. | In supramolecular chemistry, a great deal of attention has focused on regulating guest binding via an external stimulus. To utilize the same effector for both highly guest-selective positive and negative allosteric effects, however, stricter and more precise regulation of the host structure is required. A novel alloste... |
12516075 | Enhancement of in vitro and in vivo microdialysis recovery of SB-265123 using Intralipid and Encapsin as perfusates. | This study was conducted to compare the ability of two potential microdialysis perfusates to enhance the recovery of SB-265123, a lipophilic, highly protein-bound compound, both in vitro and in vivo. Initial in vitro experiments established that the recovery of SB-265123 by microdialysis using normal saline as a perfus... |
12515536 | Plasma membrane cholesterol: a possible barrier to intracellular oxygen in normal and mutant CHO cells defective in cholesterol metabolism. | The effect of the cholesterol content of the plasma membrane on the intracellular concentration of oxygen in Chinese hamster ovary (CHO) cells and their mutants was investigated by EPR oximetry. Total and free cholesterol content was significantly higher in 25 RA CHO cells as compared to wild-type and M 19 CHO cells, w... |
12513087 | Self-assembled supramolecular M9 (Mn(II), Fe(III), Zn(II)), M5 (Fe(III)), and [M3]2 (Pb(II)) complexes: structural, magnetic, and Mössbauer properties. | The tritopic ligand 2poap self-assembles in the presence of Zn(NO(3))(2) and Fe(NO(3))(3) to form homoleptic [3 x 3] nonanuclear M(9) (M = Zn(II), Fe(III)) square grid structures and with Pb(ClO(4))(2) to form a dimerized linear trinuclear [Pb(3)](2) structure. Cl2poap and Cl2poapz form self-assembled homoleptic [3 x 3... |
12514050 | Phylogenetic position and in situ identification of ectosymbiotic spirochetes on protists in the termite gut. | Phylogenetic relationships, diversity, and in situ identification of spirochetes in the gut of the termite Neotermes koshunensis were examined without cultivation, with an emphasis on ectosymbionts attached to flagellated protists. Spirochetes in the gut microbial community investigated so far are related to the genus ... |
12514023 | Substrate specificity and enantioselectivity of 4-hydroxyacetophenone monooxygenase. | The 4-hydroxyacetophenone monooxygenase (HAPMO) from Pseudomonas fluorescens ACB catalyzes NADPH- and oxygen-dependent Baeyer-Villiger oxidation of 4-hydroxyacetophenone to the corresponding acetate ester. Using the purified enzyme from recombinant Escherichia coli, we found that a broad range of carbonylic compounds t... |
12511593 | A PEST sequence in ABCA1 regulates degradation by calpain protease and stabilization of ABCA1 by apoA-I. | Cholesterol-loaded macrophage foam cells are a central component of atherosclerotic lesions. ABCA1, the defective molecule in Tangier disease, mediates the efflux of phospholipids and cholesterol from cells to apoA-I, reversing foam cell formation. In ABCA1, we identified a sequence rich in proline, glutamic acid, seri... |
12511494 | Targeted disruption of the alpha-amylase gene in the hyperthermophilic archaeon Sulfolobus solfataricus. | Sulfolobus solfataricus secretes an acid-resistant alpha-amylase (amyA) during growth on starch as the sole carbon and energy source. Synthesis of this activity is subject to catabolite repression. To better understand alpha-amylase function and regulation, the structural gene was identified and disrupted and the resul... |
12511493 | Combinatorial redesign of the DNA binding specificity of a prokaryotic helix-turn-helix repressor. | Redesign of the bacteriophage 434 Cro repressor was accomplished by using an in vivo genetic screening system to identify new variants that specifically bound previously unrecognized DNA sequences. Site-directed, combinatorial mutagenesis of the 434 Cro helix-turn-helix (HTH) motif generated libraries of new variants w... |
12511485 | Biochemical characterization of a mutationally altered protein translocase: proton motive force stimulation of the initiation phase of translocation. | Protein translocation across the Escherichia coli plasma membrane is facilitated by concerted actions of the SecYEG integral membrane complex and the SecA ATPase. A secY mutation (secY39) affects Arg357, an evolutionarily conserved and functionally important residue, and impairs the translocation function in vivo and i... |
12512082 | Evaluation of lipopolysaccharide aggregation by light scattering spectroscopy. | Lipopolysaccharides (LPS) are cell wall components of Gram-negative bacteria. These molecules behave as bacterial endotoxins and their release into the bloodstream is a determinant of the development of a wide range of pathologies. These amphipathic molecules can self-aggregate into supramolecular structures with diffe... |
12408751 | Ceramide: second messenger or modulator of membrane structure and dynamics? | The physiological role of ceramide formation in response to cell stimulation remains controversial. Here, we emphasize that ceramide is not a priori an apoptotic signalling molecule. Recent work points out that the conversion of sphingomyelin into ceramide can play a membrane structural (physical) role, with consequenc... |
12358599 | Extensive temporally regulated reorganization of the lipid raft proteome following T-cell antigen receptor triggering. | Signalling by immunoreceptors is orchestrated at specific plasma membrane microdomains, referred to as lipid rafts. Here we present a proteomics approach to the temporal analysis of protein association with lipid rafts following T-cell antigen receptor (TCR) triggering. We show that TCR engagement promotes the temporal... |
14530305 | Molecular recognition at the protein-hydroxyapatite interface. | Proteins found in mineralized tissues act as nature's crystal engineers, where they play a key role in promoting or inhibiting the growth of minerals such as hydroxyapatite (bones/teeth) and calcium oxalate (kidney stones). Despite their importance in hard-tissue formation and remodeling, and in pathological processes ... |
14530799 | The neuropharmacological basis for the use of memantine in the treatment of Alzheimer's disease. | Memantine has been demonstrated to be safe and effective in the symptomatic treatment of Alzheimer's disease (AD). While the neurobiological basis for the therapeutic activity of memantine is not fully understood, the drug is not a cholinesterase inhibitor and, therefore, acts differently from current AD therapies. Mem... |
12509880 | Free base meso-tetraaryl-morpholinochlorins and porpholactone from meso-tetraaryl-2,3-dihydroxy-chlorin. | meso-Tetraaryl-2,3-dihydroxychlorins (1) were converted in one step to the novel free base macrocycles meso-tetraaryl-2,3-dialkoxy-2a-oxa-2a-homoporphyrins (morpholinochlorins, 3). Their bathochromically shifted chlorin-type UV-vis spectra indicate the presence of a nonplanar chromophore. The structure of meso-tetratol... |
12509471 | Role of ALDP (ABCD1) and mitochondria in X-linked adrenoleukodystrophy. | Peroxisomal disorders have been associated with malfunction of peroxisomal metabolic pathways, but the pathogenesis of these disorders is largely unknown. X-linked adrenoleukodystrophy (X-ALD) is associated with elevated levels of very-long-chain fatty acids (VLCFA; C(>22:0)) that have been attributed to reduced peroxi... |
12509156 | Rayleigh light scattering study on the supramolecular interactions of beta-cyclodextrin derivatives with tetrakis(4-methoxylphenyl)porphyrin. | The supramolecular interactions of beta-cyclodextrin(beta-CD) and four kinds of alkylated beta-cyclodextrin (beta-CDs), i.e. heptakis (2,6-di-O-isobutyl)-beta-cyclodextrin (Ob-beta-CD), heptakis (2,6-di-O-n-octyl)-beta-cyclodextrin (Oc-beta-CD), heptakis (2,6-di-O-n-dodecyl)-beta-cyclodextrin (Od-beta-CD) and heptakis ... |
12509143 | Selective complex formation of some chromogenic calix[4]arene derivatives detected by Fourier transform infrared spectroscopy 1. Solution experiments. | A calix[4]arene derivative containing ethoxycarbonylmethoxy groups in the coordination sphere and an iminopyridinium indicator group was studied by FT-IR spectroscopy in acetonitrile solution. The characteristic changes of v(C=O) stretching vibration offered an opportunity for the improvement on selectivity of the ion ... |
12508373 | Effects of Tetrandrine and QYT on ICAM-1 and SOD gene expression in pancreas and liver of rats with acute pancreatitis. | <h4>Aim</h4>Available experimental evidence from both clinical and animal models shows that both Chinese medicines tetrandine (Tet) and Qing Yi Tong (QYT) have positive treatment effects on acute pancreatitis (AP). This investigation was conducted to explore the treatment mechanisms of Tet and QYT on AP at the molecula... |
12507478 | Identification of novel interactions in HIV-1 capsid protein assembly by high-resolution mass spectrometry. | The pleomorphic nature of the immature and mature HIV-1 virions has made it difficult to characterize intersubunit interactions using traditional approaches. While the structures of isolated domains are known, the challenge is to identify intersubunit interactions and thereby pack these domains into supramolecular stru... |
12506392 | A family of low-molecular-weight hydrogelators based on L-lysine derivatives with a positively charged terminal group. | A family of L-lysine-based low-molecular-weight compounds with various positively charged terminals (pyridinium and imidazolium derivatives) was synthesized and its gelation behavior in water was investigated. Most of the compounds can be very easily synthesized in high yields (total yields >90 %), and they function as... |
12506385 | Functional supramolecular devices: [M4IIL4]8+ [2 x 2]-grid-type complexes as multilevel molecular electronic species. | The [M(4)(II)L(4)](8+) [2 x 2]-grid-type complexes 1-8 present a set of features of particular interest for potential applications. All complexes exhibit multiple reduction levels at low reduction potentials paired with rather high stability. The modulation of the reduction potentials is possible by introduction of app... |
12506373 | Formation and chemical reactivities of a new type of double-butterfly [[Fe2(mu-CO)(CO)6]2(mu-SZS-mu)]2-: synthetic and structural studies on novel linear and macrocyclic butterfly Fe/E (E=S, Se) cluster complexes. | A new type of double-butterfly [[Fe(2)(mu-CO)(CO)(6)](2)(mu-SZS-mu)](2-) (3), a dianion that has two mu-CO ligands, has been synthesized from dithiol HSZSH (Z=(CH(2))(4), CH(2)(CH(2)OCH(2))(1-3)CH(2)), [Fe(3)(CO)(12)], and Et(3)N in a molar ratio of 1:2:2 at room temperature. Interestingly, the in situ reactions of dia... |
12506363 | Crown ethers as ancillary ligands in the assembly of silver(i) aggregates containing embedded acetylenediide. | Five silver(I) double salts containing embedded acetylenediide, [Ag([12]crown-4)(2)][Ag(10)(C(2))(CF(3)CO(2))(9)([12]crown-4)(2)(H(2)O)(3)] x H(2)O (2), [Ag(2)C(2) x 5 AgCF(3)CO(2) x (benzo[15]crown-5) x 2 H(2)O] x 0.5 H(2)O (3), [Ag(4)([18]crown-6)(4)(H(2)O)(3)][Ag(18)(C(2))(3)(CF(3)CO(2))(16)(H(2)O)(2.5)] x 2.5 H(2)O... |
12506362 | [60]Fullerene: a versatile photoactive core for dendrimer chemistry. | Owing to their special photophysical properties, fullerene derivatives are good candidates to demonstrate dendritic effects. In particular, the triplet lifetimes of a C(60) core can be used to evaluate its degree of isolation from external contacts. On the other hand, the fullerene core can act as a terminal energy rec... |
12504082 | Human IL-21 and IL-4 bind to partially overlapping epitopes of common gamma-chain. | Interleukin 21 (IL-21) is a recently identified novel cytokine that plays an important role in the regulation of B, T, and NK cell functions. Its effects depend on binding to and signaling through an IL-21 receptor complex consisting of the IL-21 receptor (IL-21R) and the common gamma-chain (gamma(c)). In this study us... |
12502852 | Mouse cytomegalovirus immediate-early protein 1 binds with host cell repressors to relieve suppressive effects on viral transcription and replication during lytic infection. | Herpesviruses start their transcriptional cascade at nuclear domain 10 (ND10). The deposition of virus genomes at these nuclear sites occurs due to the binding of the interferon-inducible repressor protein promyelocytic leukemia protein (PML) and/or Daxx to a viral DNA-protein complex. However, the presence of repressi... |
12502815 | Increased mucosal transmission but not enhanced pathogenicity of the CCR5-tropic, simian AIDS-inducing simian/human immunodeficiency virus SHIV(SF162P3) maps to envelope gp120. | Through rapid serial transfer in vivo, the chimeric CCR5-tropic simian/human immunodeficiency virus SHIV(SF162) evolved from a virus that is nonpathogenic and poorly transmissible across the vaginal mucosa to a variant that still maintains CCR5 usage but which is now pathogenic and establishes intravaginal infection ef... |
12502808 | Ubiquitin ligase activities of Bombyx mori nucleopolyhedrovirus RING finger proteins. | The genome of Bombyx mori nucleopolyhedrovirus (BmNPV) is predicted to contain six RING finger proteins: IAP1, ORF35, IAP2, CG30, IE2, and PE38. Several other members of the RING finger family have recently been shown to have the ubiquitin-ligase (E3) activity. We thus examined whether BmNPV RING finger proteins have t... |
12502807 | Adenovirus type 5 DNA binding protein stimulates binding of DNA polymerase to the replication origin. | The adenovirus (Ad) DNA-binding protein (DBP) is essential for the elongation phase of Ad DNA replication by unwinding the template in an ATP-independent fashion, employing its capacity to form multimers. DBP also enhances the rate of initiation, with the highest levels obtained at low concentrations of Ad DNA polymera... |
12499205 | A type II pathway for fatty acid biosynthesis presents drug targets in Plasmodium falciparum. | It has long been held that the malaria parasite, Plasmodium sp., is incapable of de novo fatty acid synthesis. This view has recently been overturned with the emergence of data for the presence of a fatty acid biosynthetic pathway in the relict plastid of P. falciparum (known as the apicoplast). This pathway represents... |
12499171 | Susceptibility of Candida dubliniensis to salivary histatin 3. | Candida dubliniensis is a recently described Candida species associated with oral candidiasis in human immunodeficiency virus (HIV)-infected patients and patients with AIDS. The majority of C. dubliniensis clinical isolates tested to date are susceptible to the commonly used antifungal drugs, including fluconazole, ket... |
12496200 | Role of avian pathogenic Escherichia coli virulence factors in bacterial interaction with chicken heterophils and macrophages. | Avian pathogenic Escherichia coli (APEC) cause extraintestinal disease in avian species via respiratory tract infection. Virulence factors associated with APEC include type 1 and P fimbriae, curli, aerobactin, lipopolysaccharide (LPS), K1 capsular antigen, temperature-sensitive hemagglutinin (Tsh), and an uncharacteriz... |
12496195 | Cytotoxic effects of streptolysin o and streptolysin s enhance the virulence of poorly encapsulated group a streptococci. | Although the toxicity of streptolysin O (SLO) and streptolysin S (SLS) in purified group A streptococci (GAS) has been established, the effect of these molecules in natural infection is not well understood. To identify whether biologically relevant concentrations of SLO and SLS were cytotoxic to epithelial and phagocyt... |
12496181 | Expression of L-Selectin (CD62L), CD44, and CD25 on activated bovine T cells. | Mycobacterium bovis infection of cattle represents a natural host-pathogen interaction and, in addition to its economic and zoonotic impact, represents a model for human tuberculosis. Extravasation and trafficking of activated lymphocytes to inflammatory sites is modulated by differential expression of multiple surface... |
12496174 | Entry of the lymphogranuloma venereum strain of Chlamydia trachomatis into host cells involves cholesterol-rich membrane domains. | Chlamydiae are bacterial pathogens which develop strictly inside the epithelial cells of their hosts. The mechanism used by chlamydiae to enter cells is not well characterized; however, it is thought to consist of a receptor-mediated process. In addition, the formation of clathrin-coated pits appears to be dispensable ... |
12496151 | Both family 1 and family 2 PspA proteins can inhibit complement deposition and confer virulence to a capsular serotype 3 strain of Streptococcus pneumoniae. | Pneumococcal surface protein A (PspA), a virulence factor of Streptococcus pneumoniae, is exceptionally diverse, being classified into two major families which are over 50% divergent by sequence analysis. A family 1 PspA from strain WU2 was previously shown to impede the clearance of pneumococci from mouse blood and to... |
12493827 | Electrostatic interactions in the reconstitution of an SH2 domain from constituent peptide fragments. | Fragment complementation has been used to delineate the essential recognition elements for stable folding in Src homology 2 (SH2) domains by using NMR spectroscopy, alanine scanning, and surface plasmon resonance. The unfolded 9-kD and 5-kD peptide fragments formed by limited proteolytic digestion of the N-terminal SH2... |
12492486 | Thermoanaerobacterium thermosulfurigenes cyclodextrin glycosyltransferase. | Cyclodextrin glycosyltransferase (CGTase) uses an alpha-retaining double displacement mechanism to catalyze three distinct transglycosylation reactions. To investigate these reactions as catalyzed by the CGTase from Thermoanaerobacterium thermosulfurigenes the enzyme was overproduced (8 mg.L(-1) culture) using Bacillus... |
12490376 | Liquid formulation of a novel non-fluorinated topical quinolone, T-3912, utilizing the synergic solubilizing effect of the combined use of magnesium ions and hydroxypropyl-beta-cyclodextrin. | T3912 is a non-fluorinated topical quinolone antimicrobial agent currently under development. Its pK(a1) and pK(a2) values were determined as 5.6 and 7.5, respectively, and its intrinsic solubility at pH 7 was found to be approximately 2 microg/ml. This study evaluates the combined use of Mg(2+) ions, hydroxpyropyl-bet... |
12485736 | Nuclear magnetic resonance studies for the chiral recognition of (+)-(R)-18-crown-6-tetracarboxylic acid to amino compounds. | Chiral recognition capability of (+)-(R)-18-crown-6-tetracarboxylic acid (18C6H(4)) to various amino compounds containing 16 amino acids, five alkyl amines, seven aminoalcohols and other amino compounds in nuclear magnetic resonance (1H-NMR) analysis was investigated. In general, amino compounds having an aromatic ring... |
12485728 | On-line preconcentration and enantioselective separation of triadimenol by electrokinetic chromatography using cyclodextrins as chiral selectors. | Enantioselective separation of triadimenol, a component of systemic agricultural fungicide, by electrokinetic chromatography (EKC) using cyclodextrins (CDs) as chiral selectors was investigated. Both a neutral CD derivative, hydroxypropyl-gamma-CD (HP-gamma-CD), and an ionic one, heptakis-6-sulfato-beta-CD (HS-beta-CD)... |
12485725 | Uniformly sized molecularly imprinted polymers for bisphenol A and beta-estradiol: retention and molecular recognition properties in hydro-organic mobile phases. | Uniformly sized molecularly imprinted polymers (MIPs) for bisphenol A (BPA) have been prepared using ethylene glycol dimethacrylate (EDMA) as a cross-linker and methacrylic acid, 2-diethylaminoethyl methacrylate or 4-vinylpyridine (4-VPY) as a functional monomer or without use of a functional monomer. The MIPs obtained... |
12485720 | Micro-HPLC and standard-size HPLC for the separation of peptide stereoisomers employing an ion-exchange principle. | Standard-size (4 mm ID) and micro-HPLC columns (0.5 mm ID) packed with a quinine-based ion-exchange type chiral stationary phase are comparatively evaluated for the separation of peptide enantiomers with up to six amino acid residues. The results show that downscaling the separation system in order to gain the advantag... |
12485716 | Determination of inorganic anions via postcolumn reaction with iodide in ion chromatography. | Inorganic anions were determined as triiodide by postcolumn reaction with iodide under an acidic condition with help of alpha-cyclodextrin in ion chromatography. Analytes reacting with iodide to produce iodine could be determined by the present method. The analytes were indirectly detected at 287 or 355 nm. The presenc... |
12485399 | The synaptophysin/synaptobrevin interaction critically depends on the cholesterol content. | Synaptophysin interacts with synaptobrevin in membranes of adult small synaptic vesicles. The synaptophysin/synaptobrevin complex promotes synaptobrevin to built up functional SNARE complexes thereby modulating synaptic efficiency. Synaptophysin in addition is a cholesterol-binding protein. Depleting the membranous cho... |
12486062 | The crystal structure of the phosphorylation domain in PhoP reveals a functional tandem association mediated by an asymmetric interface. | PhoP from Bacillus subtilis belongs to the OmpR subfamily of response regulators. It regulates the transcription of several operons and participates in a signal transduction network that controls adaptation of the bacteria to phosphate deficiency. The receiver domains of two members of this subfamily, PhoB from Escheri... |
12482491 | Direct stereoselective assay of fluoxetine and norfluoxetine enantiomers in human plasma or serum by two-dimensional gas-liquid chromatography with nitrogen-phosphorus selective detection. | A method was developed and validated for the direct enantioselective assay of fluoxetine and norfluoxetine in human plasma or serum by two-dimensional capillary gas-liquid chromatography (GC). A Rtx-1 fused-silica capillary (15 mx0.25 mm I.D., 1.0 micrometer film thickness) and a hydrodex-beta-6-TBDM fused-silica capil... |
12479982 | Topically administered CB(2)-receptor agonist, JWH-133, does not decrease intraocular pressure (IOP) in normotensive rabbits. | Recent IOP and receptor localization studies suggest that the IOP effects of cannabinoids are mediated via ocular CB(1) receptors. However, it is not yet known whether CB(2) receptor agonists decrease IOP. In this study, the IOP-lowering effects of the CB(2) receptor agonist JWH-133 were studied in normotensive rabbits... |
12480282 | Enhanced transport of a novel anti-HIV agent--cosalane and its congeners across human intestinal epithelial (Caco-2) cell monolayers. | <h4>Purpose</h4>Cosalane is a potent inhibitor of HIV replication with activity against a broad range of viral targets. However, oral bioavailability of this highly lipophilic compound is extremely poor (<1%). The purpose of this study is to screen a variety of permeation enhancers (cyclodextrin derivatives, cremophor ... |
12480274 | Formulation of electrically conducting microemulsion-based organogels. | Gelatin-containing, electrically conducting, rigid water-in-oil (w/o) microemulsion-based organogels (MBG), both with and without the presence of a model drug, have been prepared using pharmaceutically acceptable oils and surfactants. As a precursor to MBG formation, preliminary formulation work was carried out investi... |
12479830 | Method for determining monohydroxybenzo[a]pyrene isomers using column-switching high-performance liquid chromatography. | A method for determining monohydroxybenzo[a]pyrene (OHBaP) isomers using column-switching high-performance liquid chromatography with fluorescence detection was developed. Eleven of 12 isomers of OHBaP (all except 6-OHBaP) were separated on an alkylamide-type reversed-phase column and, via column-switching, on a beta-c... |
12477879 | G100R mutation within 4070A murine leukemia virus Env increases virus receptor binding, kinetics of entry, and viral transduction efficiency. | Passage of 4070A murine leukemia virus (MuLV) in D17 cells resulted in a G-to-R change at position 100 within the VRA of the envelope protein (Env). Compared with 4070A MuLV, virus with the G100R Env displayed enhanced binding on target cells, internalized the virus more rapidly, and increased the overall viral titer i... |
12477872 | Contribution of the zinc finger to zinc and DNA binding by a suppressor of posttranscriptional gene silencing. | The zinc finger C(36)-X1-C(38)-X7-C(46)-X6-H(53) of the nuclearly localized C2 protein of Tomato yellow leaf curl virus China is involved in pathogenicity and suppression of posttranscriptional gene silencing (PTGS). Here, we demonstrate that the zinc finger is indispensable for the C2 protein to bind zinc and DNA. Mut... |
12477861 | Structurally conserved amino Acid w501 is required for RNA helicase activity but is not essential for DNA helicase activity of hepatitis C virus NS3 protein. | Hepatitis C virus (HCV) is a positive-strand RNA virus that encodes a helicase required for viral replication. Although HCV does not replicate through a DNA intermediate, HCV helicase unwinds both RNA and DNA duplexes. An X-ray crystal structure of the HCV helicase complexed with (dU)(8) has been solved, and the substr... |
12477859 | Role of the asialoglycoprotein receptor in binding and entry of hepatitis C virus structural proteins in cultured human hepatocytes. | We used a baculovirus-based system to prepare structural proteins of hepatitis C virus (HCV) genotype 1a. Binding of this preparation to cultured human hepatic cells was both dose dependent and saturable. This binding was decreased by calcium depletion and was partially prevented by ligands of the asialoglycoprotein re... |
12477846 | Mapping of amino acid side chains on the surface of hepatitis B virus capsids required for envelopment and virion formation. | The crystal structure of recombinant hepatitis B virus (HBV) capsids formed by 240 core proteins has recently been published. We wanted to map sites on the surface of the icosahedral 35-nm particle that are important for nucleocapsid envelopment by HBV surface proteins during virion morphogenesis. For this purpose, we ... |
12477837 | Isolation and molecular characterization of a nelfinavir (NFV)-resistant human immunodeficiency virus type 1 that exhibits NFV-dependent enhancement of replication. | During the use of a phenotypic anti-human immunodeficiency virus type 1 (HIV-1) drug resistance assay in a large set of clinical virus isolates, we found a unique variant (CL-4) that exhibited a high level of nelfinavir (NFV) resistance and rather enhanced replication under subinhibitory concentrations of NFV (0.001 to... |
12475723 | Spectra and structure of complexes formed by sodium fusidate and potassium helvolate with beta- and gamma-cyclodextrin. | The complexation of two steroid antibiotics of the fusidane family, sodium fusidate and potassium helvolate, by beta-CD and gamma-CD has been studied by using 1D and 2D-NMR techniques. Both guests form 1:1 complexes with gamma-CD and 1:2 (guest:cyclodextrin) complexes with beta-CD. Thus, both antibiotics behave as mono... |
12475722 | Determination of second-order association constants by global analysis of 1H and 13C NMR chemical shifts. Application to the complexation of sodium fusidate and potassium helvolate by beta- and gamma-cyclodextrin. | The host-guest interaction between the steroid antibiotics sodium fusidate and potassium helvolate as guests and the hosts beta- and gamma-cyclodextrin was studied by 13C and 1H NMR techniques. The analysis of chemical shifts of individual nuclei leads to inconsistent values of the association constants and fails gener... |
12358601 | Echinococcus granulosus antigen 5 is closely related to proteases of the trypsin family. | Antigen 5 (Ag5) is a dominant secreted component of the larval stage of Echinococcus granulosus, and is highly immunogenic in human infections. Although the diagnostic value of Ag5 has been thoroughly evaluated, there has been little progress in its molecular characterization and the understanding of its biological rol... |
12473456 | Crystal structure of a hypoallergenic isoform of the major birch pollen allergen Bet v 1 and its likely biological function as a plant steroid carrier. | Bet v 1l is a naturally occurring hypoallergenic isoform of the major birch pollen allergen Bet v 1. The Bet v 1 protein belongs to the ubiquitous family of pathogenesis-related plant proteins (PR-10), which are produced in defense-response to various pathogens. Although the allergenic properties of PR-10 proteins have... |
12471015 | Quantitative analysis of albumin uptake and transport in the rat microvessel endothelial monolayer. | We determined the concentration dependence of albumin binding, uptake, and transport in confluent monolayers of cultured rat lung microvascular endothelial cells (RLMVEC). Transport of (125)I-albumin in RLMVEC monolayers occurred at a rate of 7.2 fmol. min(-1). 10(6) cells(-1). Albumin transport was inhibited by cell s... |
12467710 | Quinazolines as adenosine receptor antagonists: SAR and selectivity for A2B receptors. | We have recently reported the discovery of numerous new compounds that are selective inhibitors of all of the subtypes of the adenosine receptor family via a pharmacophore database searching and screening strategy. During the course of this work we made the unexpected discovery of a potent A(2B) receptor antagonist, 4-... |
14517900 | Peptide-bond modification for metal coordination: peptides containing two hydroxamate groups. | Peptide-bond modification via N-hydroxylation has been explored as a strategy for metal coordination to induce conformational rigidity and orient side chains for specific molecular recognition. N-Hydroxyamides were prepared by reacting N-benzyloxyamino acid esters or amides with Fmoc-AA-Cl/AgCN (Fmoc: 9-fluorenylmethox... |
12445444 | Electric potential control of DNA immobilization on gold electrode. | The assembly of synthetic, controllable molecules is one of the goals in nanotechnology. The primary objective of this contribution is to selectively immobilize DNA on gold via electric potential control. The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. A new approach ... |
14516071 | Mapping of alpha- and beta-globin genes on Antarctic fish chromosomes by fluorescence in-situ hybridization. | The pathways and mechanisms of genomic change that have led to the peculiar haemoglobinless phenotype of the white-blooded Antarctic icefishes (16 species in the family Channichthyidae) constitute an important model for understanding the rapid diversification of the Antarctic notothenioid fish flock. To provide complem... |
14516070 | Okadaic acid, an inhibitor of protein phosphatase 1 and 2A, induces premature separation of sister chromatids during meiosis I and aneuploidy in mouse oocytes in vitro. | Recent advances in understanding some of the molecular aspects of chromosome segregation during mitosis and meiosis provide a background for investigating potential mechanisms of aneuploidy in mammalian germ cells. Numerous protein kinases and phosphatases have important functions during mitosis and meiosis. Alteration... |
14516069 | Reconstruction of the ancestral karyotype of eutherian mammals. | Applying the parsimony principle, i.e. that chromosomes identical in species belonging to different taxa were likely to be present in their common ancestor, the ancestral karyotype of eutherian mammals (about 100 million years old) was tentatively reconstructed. Comparing chromosome banding with all ZOO-FISH data from ... |
14516068 | Highly conserved chromosomes in an Asian squirrel (Menetes berdmorei, Rodentia: Sciuridae) as demonstrated by ZOO-FISH with human probes. | The chromosomes of Menetes berdmorei (Rodentia, Sciuridae, Sciurinae) were studied by ZOO-FISH using whole human chromosome probes. All homoeologies between M. berdmorei and human chromosomes were determined, except for two small chromosome segments. Twelve human chromosomes are conserved in a unique block of synteny; ... |
14516067 | Immunogold labeling of chromosomes for scanning electron microscopy: a closer look at phosphorylated histone H3 in mitotic metaphase chromosomes of Hordeum vulgare. | High-resolution detection of phosphorylated histone H3 at serine 10 in mitotic barley chromosomes for scanning electron microscopy was shown using a novel application of indirect immunogold labeling with Nanogold. This method permits localization and quantification of signals in a three-dimensional context. Because the... |
14516066 | Mutations in the nomad retroelement are modifiers of position-effect variegation in Drosophila melanogaster. | The E(var) 63AP mutation of Drosophila melanogaster was isolated in a genetic screen for P-element induced enhancers of wm4 variegation. Remobilization of the P-element in E(var)63AP resulted in a loss of its ability to enhance position-effect variegation (PEV) of wm4, indicating that the P-element in this mutant resul... |
14516065 | Transgene integration and chromosome alterations in two transgenic lines of tritordeum. | Plants from two transgenic lines of tritordeum (an amphiploid between Triticum turgidum cv. durum and Hordeumn chilense) have been analyzed by fluorescence in-situ hybridization (FISH) to characterize the transgene integration sites and chromosome rearrangements. Transgenic lines were transformed in two different event... |
14516064 | Distribution of XCAP-E and XCAP-D2 in the Xenopus oocyte nucleus. | Several antibodies were used to examine the distribution of two condensin members, XCAP-E and XCAP-D2, in the nucleus of Xenopus oocytes. XCAP-D2 was found to be associated with the lampbrush chromosomes. The chromosomal regions containing XCAP-D2 correspond precisely to domains of highly compacted chromatin, suggestin... |
14510473 | Molecular recognition of proline tRNA by prolyl-tRNA synthetase from hyperthermophilic archaeon, Aeropyrum pernix K1. | To investigate the recognition mechanism of tRNA(Pro) by prolyl-tRNA synthetase from hyperthermophilic archaeon, Aeropyrum pernix K1, various tRNA(Pro) transcripts were prepared by in vitro transcription system. These transcripts were aminoacylated with proline by overexpressed A. pernix prolyl-tRNA synthetase. From pr... |
14510365 | Syntheses and structural studies of calix[4]arene-nucleoside and calix[4]arene-oligonucleotide hybrids. | We have synthesized three types of calix[4]arene-nucleoside hybrids efficiently by amide bond formation between the amine functional groups of 1,3-diamino-calix[4]arene and the carboxyl groups of thymidine nucleoside derivatives. X-Ray crystallography of a homocoupled calix[4]arene-nucleoside hybrid revealed an interes... |
14501027 | Alzheimer neurofibrillary degeneration: therapeutic targets and high-throughput assays. | Neurofibrillary degeneration has primary and pivotal involvement in the pathogenesis of Alzheimer disease (AD) and other tauopathies. The inhibition of this lesion offers a promising therapeutic approach. The microtubule- associated protein (MAP) tau is abnormally hyperphosphorylated in the brain of patients with AD, a... |
14501013 | Femtomole immunodetection of synthetic and endogenous amyloid-beta oligomers and its application to Alzheimer's disease drug candidate screening. | Alzheimer's disease (AD) is a fatal, progressive dementia for which there is no cure and for which a molecular basis has yet to be established. However, considerable evidence suggests that AD is linked to neurotoxic assemblies of the 42-amino-acid peptide amyloid beta (Abeta). There is now a clear body of evidence that... |
13678330 | Protein distorsion-derived mechanism of signal discrimination in monocytes revealed using Congo red to stain activated cells. | The supramolecular dye Congo red was used to check whether monocyte activation may be mediated by a torsion-dependent mechanism preventing transduction of weak random signals in cell contacts in a way corresponding to the discrimination mechanism found in complement fixation by immune complexes. Tight cell-cell contact... |
12971728 | Four-dimensional imaging of chromatin dynamics during the assembly of the interphase nucleus. | Large-scale chromatin organization is likely to play an important role in epigenetic control of gene expression. This implies that after mitosis the correct chromatin organization must be re-established in the nuclei of the two daughter cells. Here we analyze the dynamic behavior of chromatin during the transition from... |
12971727 | Nuclear microenvironments support physiological control of gene expression. | There is growing recognition that the organization of nucleic acids and regulatory proteins is functionally linked to the assembly, localization and activity of gene regulatory machinery. Cellular, molecular, biochemical and in-vivo genetic evidence support an obligatory relationship between nuclear microenvironments w... |
12971726 | A genetic analysis of chromosome territory looping: diverse roles for distal regulatory elements. | Recent studies of nuclear organization have shown an apparent correlation between the localization of genes within the interphase nucleus and their transcriptional status. In several instances, actively transcribed gene loci have been found significantly looped away from their respective chromosome territories (CTs), p... |
12971725 | Conservation of chromosome arrangement and position of the X in mammalian sperm suggests functional significance. | We used chromosome painting to show directly that chromosomes occupy fixed positions in the nuclei of mammal but not chicken sperm. We found that the positions of homologous chromosomes are conserved in sperm of two marsupial species that diverged 50-60 million years ago. We also discovered that the X chromosome lies i... |
12971724 | Three-dimensional arrangements of centromeres and telomeres in nuclei of human and murine lymphocytes. | The location of centromeres and telomeres was studied in human and mouse lymphocyte nuclei (G0) employing 3D-FISH, confocal microscopy, and quantitative image analysis. In both human and murine lymphocytes, most centromeres were found in clusters at the nuclear periphery. The distribution of telomere clusters, however,... |
12971723 | Comparative analysis of the functional genome architecture of animal and plant cell nuclei. | Many studies have shown that the functional architecture of eukaryotic genomes displays striking similarities in evolutionarily distant organisms. For example, late-replicating and transcriptionally inactive chromatin is associated with the nuclear periphery in organisms as different as budding yeast and man. These fin... |
12971722 | Transcription factories: quantitative studies of nanostructures in the mammalian nucleus. | Transcription by the three nuclear RNA polymerases is carried out in transcription factories. This conclusion has been drawn from estimates of the total number of nascent transcripts or active polymerase molecules and the number of transcription sites within a cell. Here we summarise the variety of methods used to dete... |
12971721 | Spatial organization of gene expression: the active chromatin hub. | Developmental and tissue-specific expression of higher eukaryotic genes involves activation of transcription at the appropriate time and place and keeping it silent otherwise. Unlike housekeeping genes, tissue-specific genes generally do not cluster on the chromosomes. They can be found in gene-dense regions of chromos... |
12971720 | From DNA structure to gene expression: mediators of nuclear compartmentalization and dynamics. | Eukaryotic genomes are functionally compartmentalized into chromatin domains by their attachment to a supporting structure that has traditionally been termed the nuclear matrix. Present evidence indicates the dynamics of this entity, which requires particular properties of the elements that mediate this kind of interac... |
12971719 | Chromatin folding and gene expression: new tools to reveal the spatial organization of genes. | An important aim in biology is to understand how gene expression is regulated in the context of chromatin. Much progress has been made towards cracking the 'histone code', which describes the composition and organization of chromatin at high resolution. At the lower resolution provided by microscopy, nuclear compartmen... |
12971718 | Exploiting a minimal system to study the epigenetic control of DNA replication: the interplay between transcription and replication. | In order to analyze epigenetic factors involved in the regulation of DNA replication in higher eukaryotic cells, minimal systems have to be established. We have recently constructed a non-viral episomal vector system which replicates episomally in mammalian cells and is stably maintained in the cell in the absence of s... |
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