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10692327 | Molecular and mesoscopic properties of hydrophilic polymer-grafted phospholipids mixed with phosphatidylcholine in aqueous dispersion: interaction of dipalmitoyl N-poly(ethylene glycol)phosphatidylethanolamine with dipalmitoylphosphatidylcholine studied by spectrophotometry and spin-label electron spin resonance. | Spin-label electron spin resonance (ESR) spectroscopy, together with optical density measurements, has been used to investigate, at both the molecular and supramolecular levels, the interactions of N-poly(ethylene glycol)-phosphatidylethanolamines (PEG-PE) with phosphatidylcholine (PC) in aqueous dispersions. PEG-PEs a... |
10692320 | Protonation of lysine residues inverts cation/anion selectivity in a model channel. | A dimeric alamethicin analog with lysine at position 18 in the sequence (alm-K18) was previously shown to form stable anion-selective channels in membranes at pH 7.0 [Starostin, A. V., R. Butan, V. Borisenko, D. A. James, H. Wenschuh, M. S. Sansom, and G. A. Woolley. 1999. Biochemistry. 38:6144-6150]. To probe the char... |
10692318 | Kinetics studies of the cardiac Ca-ATPase expressed in Sf21 cells: new insights on Ca-ATPase regulation by phospholamban. | Kinetics studies of the cardiac Ca-ATPase expressed in Sf21 cells (Spodoptera frugiperda insect cells) have been carried out to test the hypotheses that phospholamban inhibits Ca-ATPase cycling by decreasing the rate of the E1.Ca to E1'.Ca transition and/or the rate of phosphoenzyme hydrolysis. Three sample types were ... |
10689291 | On the calculation of Gibbs energy corresponding to enantioselective interactions at a direct HRGC separation of enantiomers. | A novel procedure is proposed for the calculation of Gibbs energy corresponding to enantiospecific interactions of 2-(2, 4-dinitrophenoxy)-, 2-phenoxy-, and 2-halogen-n-pentane enantiomers with a beta-cyclodextrin (ChirasilDex) stationary phase under gas chromatographic conditions. This energy is calculated from retent... |
10684906 | Control of synaptic depression by glutamate transporters. | The role of glutamate transporters in the regulation of synaptic depression was examined in the avian nucleus magnocellularis. Repetitive stimulation of presynaptic auditory nerve fibers resulted in acute depression of EPSCs. Pharmacological blockade of glutamate transport in glial cells enhanced residual glutamate in ... |
10684899 | Neuroactive steroid 3alpha-hydroxy-5alpha-pregnan-20-one modulates electrophysiological and behavioral actions of ethanol. | Neuroactive steroids are synthesized de novo in brain, yet their physiological significance remains elusive. We provide biochemical, electrophysiological, and behavioral evidence that several specific actions of alcohol (ethanol) are mediated by the neurosteroid 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THP; ... |
10684300 | Hepatitis B virus X protein colocalizes to mitochondria with a human voltage-dependent anion channel, HVDAC3, and alters its transmembrane potential. | Understanding the mechanism(s) of action of the hepatitis B virus (HBV)-encoded protein HBx is fundamental to elucidating the underlying mechanisms of chronic liver disease and hepatocellular carcinoma caused by HBV infection. In our continued attempts to identify cellular targets of HBx, we have previously reported th... |
10684279 | Mapping in solution shows the peach latent mosaic viroid to possess a new pseudoknot in a complex, branched secondary structure. | We have investigated the secondary structure of peach latent mosaic viroid (PLMVd) in solution, and we present here the first description of the structure of a branched viroid in solution. Different PLMVd transcripts of plus polarity were produced by using the circularly permuted RNA method and the exploitation of RNA ... |
10684267 | Feline immunodeficiency virus Vif localizes to the nucleus. | Monoclonal antibodies prepared against recombinant Vif derived from the 34TF10 strain of feline immunodeficiency virus (FIV) were used to assess the expression and localization of Vif in virus-infected cells. Analyses by Western blotting and by immunoprecipitation from cells infected with FIV-34TF10 revealed the presen... |
10684265 | Covalent modification of the transactivator protein IE2-p86 of human cytomegalovirus by conjugation to the ubiquitin-homologous proteins SUMO-1 and hSMT3b. | The 86-kDa IE2 protein (IE2-p86) of human cytomegalovirus (HCMV) is a potent transactivator of viral as well as cellular promoters. Several lines of evidence indicate that this broad transactivation spectrum is mediated by protein-protein interactions. To identify novel cellular binding partners, we performed a yeast t... |
10679632 | Hydroxyl group interactions in polysaccharides: a deuterium-induced differential isotope shift 13C-NMR investigation. | The secondary isotope shift in (13)C-nmr spectra in water was used to obtain information on the interactions of hydroxyl groups with their environment in polysaccharides. Specifically, the possibility of detecting the preference of intramolecular hydrogen bonding with respect to solvation was investigated. Different al... |
10681359 | Efficacy of SCH56592 in a rabbit model of invasive aspergillosis. | SCH56592 (SCH) was evaluated in an immunosuppressed rabbit model of invasive aspergillosis. SCH was more effective than similar doses of itraconazole and as effective as amphotericin B in the clearance of Aspergillus spp. from tissues. Compared with controls, SCH regimens reduced mortality, improved survival, and signi... |
10681347 | Mutations in ribosomal protein L16 conferring reduced susceptibility to evernimicin (SCH27899): implications for mechanism of action. | A clinical isolate of Streptococcus pneumoniae (SP#5) that showed decreased susceptibility to evernimicin (MIC, 1.5 microgram/ml) was investigated. A 4,255-bp EcoRI fragment cloned from SP#5 was identified by its ability to transform evernimicin-susceptible S. pneumoniae R6 (MIC, 0.03 microgram/ml) such that the everni... |
10681346 | Pharmacokinetics of SCH 56592, a new azole broad-spectrum antifungal agent, in mice, rats, rabbits, dogs, and cynomolgus monkeys. | SCH 56592 is a new broad-spectrum azole antifungal agent that is in phase 3 clinical trials for the treatment of serious systemic fungal infections. The pharmacokinetics of this drug candidate were evaluated following its intravenous (i.v.) or oral (p.o.) administration as a solution in hydroxypropyl-beta-cyclodextrin ... |
10681344 | Effects of atovaquone and diospyrin-based drugs on the cellular ATP of Pneumocystis carinii f. sp. carinii. | Atovaquone (also called Mepron, or 566C80) is a napthoquinone used for the treatment of infections caused by pathogens such as Plasmodium spp. and Pneumocystis carinii. The mechanism of action against the malarial parasite is the inhibition of dihydroorotate dehydrogenase (DHOD), a consequence of blocking electron tran... |
10681320 | Faropenem transport across the renal epithelial luminal membrane via inorganic phosphate transporter Npt1. | We previously showed that the mouse inorganic phosphate transporter Npt1 operates in the hepatic sinusoidal membrane transport of anionic drugs such as benzylpenicillin and mevalonic acid. In the present study, the mechanism of renal secretion of penem antibiotics was examined by using a Xenopus oocyte expression syste... |
10678952 | Role of decay-accelerating factor domains and anchorage in internalization of Dr-fimbriated Escherichia coli. | Dr-fimbriated Escherichia coli capable of invading epithelial cells recognizes human decay-accelerating factor (DAF) as its cellular receptor. The role of extracellular domains and the glycosylphosphatidylinositol anchor of DAF in the process of internalization of Dr(+) E. coli was characterized in a cell-cell interact... |
10678946 | Characterization of in vitro DNA binding sites of the EUO protein of Chlamydia psittaci. | The EUO gene of chlamydia is highly expressed early in the developmental cycle, relative to other genes, but continues to be expressed throughout the active growth phases. The precise function of EUO protein is not known, but it binds to DNA in vitro. In this study, we developed a selection and amplification scheme for... |
10671374 | Nidogen-1 regulates laminin-1-dependent mammary-specific gene expression. | Nidogen-1 (entactin) acts as a bridge between the extracellular matrix molecules laminin-1 and type IV collagen, and thus participates in the assembly of basement membranes. To investigate the role of nidogen-1 in regulating cell-type-specific gene expression in mammary epithelium, we designed a culture microecosystem ... |
10673290 | The human trefoil peptide, TFF1, is present in different molecular forms that are intimately associated with mucus in normal stomach. | <h4>Background</h4>TFF1 is a 6.5 kDa secreted protein that is expressed predominantly in normal gastric mucosa. It is coexpressed with mucins and it can form dimers via a free carboxy terminal cysteine residue.<h4>Aims</h4>To investigate the molecular forms of TFF1 that are present in normal human stomach and the assoc... |
10669757 | Calcium depletion dissociates and activates heterodimeric notch receptors. | Notch receptors participate in a highly conserved signaling pathway that regulates morphogenesis in multicellular animals. Maturation of Notch receptors requires the proteolytic cleavage of a single precursor polypeptide to produce a heterodimer composed of a ligand-binding extracellular domain (N(EC)) and a single-pas... |
10666458 | Recognition of 5-aminouracil (U(#)) in the central strand of a DNA triplex: orientation selective binding of different third strand bases. | A necessary feature of the natural base triads for triplex formation is the requirement of a purine (A or G) in the central position, since only these provide sets of two hydrogen bond donors/acceptors in the major groove of the double helix. Pyrimidine bases devoid of this feature have incompatible complementarity and... |
10666450 | Transactivation and growth suppression by the gut-enriched Krüppel-like factor (Krüppel-like factor 4) are dependent on acidic amino acid residues and protein-protein interaction. | Gut-enriched Krüppel-like factor (GKLF or KLF4) is a pleiotropic (activating and repressive) transcription factor. This study characterizes the mechanisms of transactivation by GKLF. Using a GAL4 fusion assay, the activating domain of murine GKLF was localized to the 109 amino acid residues in the N-terminus. Site-dire... |
10666268 | A chimeric protein containing the N terminus of the adeno-associated virus Rep protein recognizes its target site in an in vivo assay. | The Rep78 and Rep68 proteins of adeno-associated virus (AAV) type 2 are involved in DNA replication, regulation of gene expression, and targeting site-specific integration. They bind to a specific Rep recognition sequence (RRS) found in both the viral inverted terminal repeats and the AAVS1 integration locus on human c... |
20865137 | Factors Contributing to Aromatic Stacking in Water: Evaluation in the Context of DNA. | We report the use of thermodynamic measurements in a self-complementary DNA duplex (5'-dXCGCGCG)(2), where X is an unpaired natural or nonnatural deoxynucleoside, to study the forces that stabilize aqueous aromatic stacking in the context of DNA. Thermal denaturation experiments show that the core duplex (lacking X) is... |
19401751 | Two-photon holography in 3-D photopolymer host-guest matrix: errata. | : Correction to References. Commercial codes of the chemicals are added. |
19002973 | Advances in animal cell recombinant protein production: GS-NS0 expression system. | The production of recombinant proteins using mammalian cell expression systems is of growing importance within biotechnology, largely due to the ability of specific mammalian cells to carry out post-translational modifications of the correct fidelity. The Glutamine Synthetase-NS0 system is now one such industrially imp... |
18967867 | Effect of cyclodextrins on the stability of adriamycin, adriamycinol, adriamycinone and daunomycin. | The stability of adriamycin (ADR), adriamycinol, adriamycinone (ADR-ONE) and daunomycin in the presence of alpha-, beta- and gamma-cyclodextrins (CDs) was studied using high-performance liquid chromatography. It was found that alpha-CD did not affect the degradation of tested compounds, beta-CD caused a little effect a... |
10814364 | Photolabile dendrimers using o-nitrobenzyl ether linkages | [reaction: see text] Benzyl aryl ether dendrimers containing photosensitive, veratryl-based o-nitrobenzyl AB linkages (bold bonds) were prepared to the third generation and shown to undergo site-specific degradation when irradiated with ultraviolet light. |
10814348 | Macrocyclization and molecular interlocking via Mitsunobu alkylation: highlighting the role of C-H...O interactions in templating | [reaction: see text] A series of diimide-based macrocycles have been prepared using Mitsunobu-mediated alkylation as the macrocyclization step. These macrocycles could not be incorporated into [2]catenanes using previously established building blocks and coupling methodology. However, when one of the macrocycle synthes... |
10814311 | Chemospecific monofunctionalization of alpha-cyclodextrin in the solid state | [reaction: see text] The properties of the self-assembling aziadamantane inclusion complex with two alpha-cyclodextrin molecules have been exploited to perform a chemospecific monofunctionalization of alpha-cyclodextrin. The insertion of the photochemically generated carbenes takes place chemospecifically into the cycl... |
10814300 | New hydrogen-bonded donor-acceptor pairs between dipyridylacetylenes and 2,5-dichloro-3,6-dihydroxyl-1,4-benzoquinone | [structure: see text] The crystalline donor-acceptor hydrogen-bonding complexes between 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (chloranilic acid) and dipyridylacetylenes (DPA) [2,2'-DPA, 3,3'-DPA, and 4,4'-DPA] were prepared, and crystal structures were revealed by X-ray analysis. The structures of the complexes a... |
10807172 | Photophysical and electrochemical characterisation of the interactions between components in neutral pi-associated | The electrochemical and photophysical properties of a variety of neutral pi-associated [2]catenanes have been explored by using cyclic voltammetry, absorption and luminescence spectrophotometry and the measurement of exited-state lifetimes. Several trends that could be correlated with interactions between the mechanica... |
10747410 | Calix | Chiral calix[4]arene derivatives with four O-(N-acetyl-PhgOMe), (1), (Phg denotes R-phenylglycine), or O-(N-acetyl-LeuOMe) (2) strands have been synthesised. Both compounds exist in chloroform in stable cone conformations with a noncovalently organised cavity at the lower rim that is formed by circular interstrand amid... |
10747407 | Assembly of silver(I) polymers with helical and lamellar structures | The new versatile multidentate nonchelating ligand 1,2-bis[(2-pyr-imidinyl)-sulfanylmethyl]benzene (bpsb) was designed and prepared for supramolecular syntheses. Self-assembly between silver nitrate and the bpsb ligand resulted in the polymer [Ag4(bpsb)2-(NO3)4]n (1) with a single-stranded helical chain structure. Each... |
10741674 | Optimal sensitivity for molecular recognition MAC-mode AFM | Molecular recognition force microscopy (MRFM) using the magnetic AC mode (MAC mode) atomic force microscope (AFM) was recently investigated to locate and probe recognition sites. A flexible crosslinker carrying a ligand is bound to the tip for the molecular recognition of receptors on the surface of a sample. In this r... |
10735445 | Supramolecular chemistry of amine--phenol adducts; novel three-dimensional framework structures in adducts of bis(2-aminoethyl)amine with 4,4'-sulfonyldiphenol, 1,1,1-tris(4-hydroxyphenyl)-ethane and 3,5-dihydroxybenzoic acid, and in the methanol-solvated adduct of tris(2-aminoethyl)-amine with 4,4'-biphenol | Bis(2-aminoethyl)amine-4,4'-sulfonyldiphenol (1/3) (1) (orthorhombic Pccn with Z' = 0.5) is a salt, [HN(CH2CH2NH3)2]2+.[O2S(C6H4O)2-.[O2S(C6H4OH)2]2, containing both dianionic and neutral bis-phenol units. The neutral and anionic bis-phenol units are linked by strong O-H...O- hydrogen bonds to form ladders built from R... |
10735443 | meso-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane as a building block in supramolecular chemistry; salts formed with 2,2-biphenol, 4,4-thiodiphenol, 4,4-sulfonyldiphenol, 3-and 4-hydroxybenzoic acids, 3,5-dihydroxybenzoic acid and phenylphosphonic acid; supramolecular structures in zero, one, two and thr... | The structure of meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-2,2'-biphenol (1/2), (C16H36N4).(C12H10O2)2 (1), is a salt [C16H38N4]2+.2[HOC6H4C6H4O]-: the cations are centrosymmetric with two protons held within the N4 cavity of the macrocycle by N-H...N hydrogen bonds, and the phenolate anions cont... |
10677470 | Archimedean solids: transition metal mediated rational self-assembly of supramolecular-truncated tetrahedra. | A family of nanoscale-sized supramolecular cage compounds with a polyhedral framework is prepared by self-assembly from tritopic building blocks and rectangular corner units via noncovalent coordination interactions. These highly symmetrical cage compounds are described as face-directed, self-assembled truncated tetrah... |
10671276 | Global Chirality in Rigid Decametallic Ruthenium Dendrimers. | Metallodendrimers with ten chiral Ru centers have been prepared in a stereospecific fashion (see picture; *=chiral Ru(diimine)(3) center). These molecules are conformationally rigid and exhibit well-defined global topologies: some diastereomers exhibit macroscopically chiral structures, others show a disklike topology.... |
10671274 | Three-Strand Conducting Ladder Polymers: Two-Step Electropolymerization of Metallorotaxanes. | Sequential polymerization of supramolecular metallorotaxane complexes results in three-stranded conducting ladder polymers. The internal polymer is "sandwiched" between the other two polymers to give molecular wires that are effectively insulated when the outer polymers are in their nonconducting state (shown schematic... |
10671254 | Molecular Recognition of Carbohydrates by Artificial Polypyridine and Polypyrimidine Receptors. | Despite their acyclic structure, the simple host molecules 1 and 2 can effectively hydrogen bond to monosaccharides. They show marked binding affinities to glucopyranosides in chloroform, and they are able to participate in three-dimensional recognition of monosaccharides. |
10671251 | Chromophore Alignment in a Chiral Host Provides a Sensitive Test for the Orientation - Intensity Rule of Induced Circular Dichroism. | Different inclusion modes can be realized for a bicyclic azoalkane in beta-cyclodextrin (see picture). Variations in the alignment of the azo chromophore relative to the host can be detected through NMR spectroscopy and induced circular dichroism. The latter technique produces a positive signal for the lateral conforme... |
10671243 | Supramolecular Materials with Electroactive Chemical Functions. | A diblock coil with diphenylaminophenyl side chains, oligoethylene oxide segments, and a rigid molecular pentamer of phenylene vinylene are present in the molecule studied here (see formula). When films of this material were investigated, the material was found to organize into nanostructures 12 nm in dimension. |
10655471 | Using lateral capillary forces to compute by self-assembly. | Investigations of DNA computing have highlighted a fundamental connection between self-assembly (SA) and computation: in principle, any computation can be performed by a suitable self-assembling system. In practice, exploration of this connection is limited by our ability to control the geometry and specificity of bind... |
12575146 | [Study on the extraction of volatile oil in dry ginger and the preparation of its beta-cyclodextrin inclusion compound]. | By using orthogonal tests, the optimized extraction of volatile oil was practiced by distillation. The inclusion compound of the oil-beta-cyclodextrin inclusion compound was prepared by the liquid-phase method in aqueous solution. And it was confirmed by thin layer chromatogram and differential thermal analysis. |
11832005 | [Surgical correction of complete atrioventricular septal defect with tetralogy of Fallot]. | <h4>Objective</h4>To report the surgical correction of complete atrioventricular septal defect with tetralogy of Fallot (AVSD-TOF).<h4>Methods</h4>Six consecutive patients aged 3 - 9 years underwent correction of complete AVSD-TOF. The two-patch technique for atrioventricular septal defect was used. The ventricular sep... |
11229555 | Crystal supramolecular motifs: columns of embracing Ph3PMe+ or Ph3PCI+ cations controlling formation of. | The crystal structures of (Ph3PCl)2[Cu3Cl8] (1) (triclinic, space group P1, a = 9.480(6) A, b = 10.243(8) A, c = 11.232(6) A, alpha = 86.76(4) degrees, beta = 66.62(5) degrees, gamma = 83.92(4) degrees, Z = 1) and (Ph3PMe)2[Cu3Br8] (2) (triclinic, space group P1, a = 9.795(4) A, b = 10.472(4) A, c = 11.392(4) A, alpha ... |
11220316 | New stationary phase based on beta-cyclodextrin for normal-phase HPLC group-separation of organic nitrates. | The synthesis of a beta-cyclodextrin-silica normal-phase (NP)-liquid chromatography (LC) stationary phase is reported. Silica gel was modified with (3-bromopropyl)trimethoxysilane to a 3-bromopropyl-silica that was reacted with beta-cyclodextrin, resulting in a beta-cyclodextrin-silica. To prove its usefulness in group... |
11194381 | A histopathological and immunohistochemical study of dental pulp and pulpal nerve fibers in rats after the cavity preparation using Er:YAG laser. | The purpose of this study was to investigate histopathological changes in the dental pulp after Er:YAG laser irradiation compared with those after high-speed drill preparation. For evaluation, repair of nerve fibers was observed using an immunohistochemical technique. There was no significant difference between the rem... |
11194379 | Time course of the increase in trk A expression in trigeminal neurons after tooth injury. | Injury to tooth pulp often results in extensive sprouting of sensory nerve fibers at the site of wound repair due to local increases in nerve growth factor (NGF) concentration. NGF interacts with high-affinity binding sites, termed trk A receptors, located on the cell membranes of responsive neurons. If NGF induces wou... |
10983407 | Penicillin acylase catalyzed synthesis of penicillin-G from substrates anchored in cyclodextrins. | Penicillin acylase (EC 3.5.1.11) catalyses the condensation of phenylacetic acid (PAA) and 6-aminopenicillanic acid (6-APA) to form benzylpenicillin (BP). Both PAA and 6-APA were found to form host-guest complexes with beta-methylcyclodextrin (beta m-CD) and gamma-cyclodextrin (gamma-CD) respectively. The rate of the r... |
10882077 | Activation of transcription through histone H4 acetylation by MOF, an acetyltransferase essential for dosage compensation in Drosophila. | Dosage compensation in Drosophila involves a 2-fold increase in transcription from the single male X relative to the two female X chromosomes. Regulation at the level of the chromosome involves alterations in chromatin organization: male X chromosomes appear decondensed and are marked by acetylation of histone H4 at ly... |
10866603 | Development of chiral HPLC for selenoamino acids with ICP-MS detection:application to selenium nutritional supplements. | The enantiomeric separation of three underivatized seleno-amino acids, D,L-selenocystine, and D,L-selenomethionine, and D,L-selenomethionine, with UV and ICP-MS detection is described. An HPLC column with a chiral crown ether stationary phase and a mobile phase of 0.10 M HCIO4 was used. Absolute detection limits obtain... |
10841597 | Identification of a high-affinity anti-phosphoserine antibody for the development of a homogeneous fluorescence polarization assay of protein kinase C. | In the last few years, fluorescence polarization (FP) has been applied to the development of robust, homogeneous, high throughput assays in molecular recognition research, such as ligand-protein interactions. Recently, this technology has been applied to the development of homogeneous tyrosine kinase assays, since ther... |
10836547 | Photophysical properties of carborane-containing derivatives of 5,10,15,20-tetra(p-aminophenyl)porphyrin. | Absorption, fluorescence emission, fluorescence excitation spectra and fluorescence decay kinetics of carborane derivatives of 5,10,15,20-tetra(p-aminophenyl)porphyrin have been investigated. Carborane derivatives are prepared by acylation of the amino groups of 5,10,15,20-tetra(p-aminophenyl)porphyrin by 9-carboranyl ... |
10836266 | Self-programmable, self-assembling two-dimensional genetic matter. | Putative two-dimensional coding systems can be constructed from aqueous solutions of purine and pyrimidine nucleic acid bases evaporated at moderate temperatures on the surfaces of inorganic solids. The resultant structures are monolayers which are formed spontaneously by molecular self-assembly and they have been obse... |
10820888 | A comparison of vancomycin and sulfated beta-cyclodextrin as chiral selectors for enantiomeric separations of selenoamino acids using capillary electrophoresis with UV absorbance detection. | The enantiomeric separation of three selenoamino acids, D,L-selenomethionine, D,L-selenoethionine and D,L-selenocystine is described. Both sulfated beta-cyclodextrin and vancomycin have been successfully used to separate all enantiomers of the compounds with UV detection. Reproducible separations, in terms of peak area... |
10805318 | Investigation of electroplated conducting polymers as antibody receptors in immunosensors. | Antibodies raised against the conducting polymer, carbazole as a hapten, react to modulate the polymer's electrochemistry. Using cyclic voltammetry the reaction of the antiserum was discovered to influence the polymer matrix's electrochemistry by an amperometric response. It is suggested that these observation form the... |
10776522 | Postoperative lavage and on demand surgical intervention in the treatment of acute necrotizing pancreatitis. | <h4>Objective</h4>To analyse our experience with a combined approach of postoperative local lavage and on demand surgical intervention in the treatment of acute necrotizing pancreatitis.<h4>Patients and methods</h4>All patients operated on for acute pancreatitis in a tertiary hospital between June 1993 and July 1997 we... |
10766440 | Oligonucleotide conjugates of Eu(III) tetraazamacrocycles with pendent alcohol and amide groups promote sequence-specific RNA cleavage. | Eu(III) complexes of two neutral bifunctional tetraaaza macrocyclic ligands ¿1-[1-carboxamido-3-(4-nitrophenyl)propyl]-4,7,10-tris(2-hydroxyethyl)-1 ,4,7,10-tetraazacyclododecane and 2-(4-nitrobenzyl)-1,4,7,10-tetrakis(2-hydroxyethyl)-1,4,7,10-tetraaza cyclododecane¿ are prepared. Eu(III) complexes of the isothiocyanat... |
10766021 | Biomolecular stability and life at high temperatures. | It is not clear what the upper temperature limit for life is, or what specific factors will set this limit, but it is generally assumed that the limit will be dictated by molecular instability. In this review, we examine the thermal stability of two key groups of biological molecules: the intracellular small molecules/... |
10763364 | [Severe craniocerebral trauma in multiple trauma. An assessment of the interaction of local and systemic mediator responses]. | Isolated severe head trauma (SHT) or SHT in combination with multiple injuries are important factors for the prognosis of morbidity and mortality in patients suffering from the consequences of accidents. The prognosis mainly depends on the presence of primary mechanic brain injury and the development of secondary brain... |
10747417 | The formation of heterodimers by vancomycin group antibiotics. | The formation of heterodimers in mixtures of glycopeptide antibiotics has been detected by electrospray ionization mass spectrometry (ESI-MS), and dimerization constants have been determined. By using NMR spectroscopy, it has been shown that these heterodimers indeed exist in aqueous solution. The dimerization constant... |
10737412 | Effect of noise exposure on rat cardiac peripheral benzodiazepine receptors. | Noise is an environmental physical agent, which is regarded as a stressful stimulus: impairment and modifications in biological functions are reported, after loud noise exposure, at several levels in human and animal organs and apparatuses, as well as in the endocrine, cardiovascular and nervous system. In the present ... |
10735447 | Correlation of structural and physico-chemical parameters with the bioactivity of alkylated derivatives of indole-3-acetic acid, a phytohormone (auxin). | As part of molecular recognition studies on the phytohormone indole-3-acetic acid (IAA) a series of alkylated IAAs has been examined. Phenyl-ring substitution (alkyl = methyl and ethyl) at positions 4-, 6- or 7- as well as pyrrole substitution at the 2-site resulted in the six compounds which are analyzed: 2-Me-IAA, 4-... |
10735301 | Analysis of cis-trans isomers and enantiomers of sertraline by cyclodextrin-modified micellar electrokinetic chromatography. | In this work development, optimization and validation of a cyclodextrin-modified micellar electrokinetic chromatography (CD-modified MEKC) method is proposed to resolve separation of the sertraline hydrochloride and synthesis-related substances. Sertraline hydrochloride, the cis-(1S,4S) enantiomer form, is used as an a... |
10735300 | Enantiospecific determination of PNU-83894 and its major metabolite, PNU-83892, in plasma, and its application to the characterization of the enantioselective pharmacokinetics of PNU-83894 in the dog. | A chiral method for the simultaneous analysis of the (+)- and (-)-enantiomers of PNU-83894 and its metabolite, PNU-83892, in plasma was developed to characterize the enantioselective pharmacokinetics of PNU-83894, a potential anticonvulsant candidate. The method involves solid-phase extraction (phenyl column) of the en... |
10735298 | Stereospecific analysis of lorazepam in plasma by chiral column chromatography with a circular dichroism-based detector. | The chiral separation of lorazepam was achieved on a chiral column with UV and circular dichroism (CD) detection. The good resolution of lorazepam enantiomers was obtained on the column of beta-cyclodextrin derivative immobilized silica gel under reversed-phase conditions. The enantiomeric separation and identification... |
10735297 | Enantiomeric separation of clenbuterol by transient isotachophoresis-capillary zone electrophoresis-UV detection new optimization technique for transient isotachophoresis. | A method for the in-line preconcentration and enantioseparation of clenbuterol by transient isotachophoresis-capillary zone electrophoresis-UV absorbance detection (transient ITP-CZE-UV) has been developed. It implies the use of dimethyl-beta-cyclodextrin as chiral selector and the application of a hydrodynamic counter... |
10735294 | Separation of isomeric naphthalenesulphonic acids by micro high-performance liquid chromatography with mobile phases containing cyclodextrin. | Aromatic sulphonic acids are important dye intermediates and the determination of the individual isomers after their preparation by sulphonation of the parent aromatic hydrocarbon is important for the monitoring of the dye production process. For this purpose, either reversed-phase chromatography with mobile phases con... |
10735291 | High-performance liquid chromatographic separation of the enantiomers of unusual alpha-amino acid analogues. | The direct and indirect stereochemical resolution of the enantiomers of ring- and alpha-methyl-substituted phenylalanines and phenylalanine amides was attempted by high-performance liquid chromatographic methods. The direct separation was carried out on two chiral stationary phases, the crown-ether-based Crownpak CR(+)... |
10732684 | Minicircular plastid DNA in the dinoflagellate Amphidinium operculatum. | Plastid DNA was purified from the dinoflagellate Amphidinium operculatum. The genes atpB, petD, psaA, psbA and psbB have been shown to reside on single-gene minicircles of a uniform size of 2.3-2.4 kb. The psaA and psbB genes lack conventional initiation codons in the expected positions, and may use GTA for translation... |
10727130 | Analysis of potassium counter ion and inorganic cation impurities in pharmaceutical drug substance by capillary electrophoresis with conductivity detection. | Capillary electrophoresis with conductivity detection is a selective and quantitative method for the analysis of counter cations, such as potassium, in pharmaceutical drug substances. It is also a sensitive and specific technique for screening and measuring inorganic impurities in drug substance samples. Both counter i... |
10727124 | Electrochemical studies of the interaction of adriamycin to DNA. | An electrochemical investigation of the interaction of adriamycin (DXH) with DNA on a Hg electrode is reported. In weakly acidic media of pH 4.0-7.0, the addition of DNA to DXH solution results in the decrease of redox peak currents. In the presence of DNA, no new peak appears and the standard rate constant k(s) is not... |
10727120 | Simultaneous interaction of steroidal drugs with gamma- and hydroxypropyl-beta-cyclodextrin studied by charge-transfer chromatography. | The simultaneous interaction of 15 steroidal drugs with tau-cyclodextrin (tauCD) and hydroxypropyl-beta-CD (HPbetaCD) was determined by charge transfer chromatography and the relative strength of interaction was calculated for each drug-tauCD-HPbetaCD ternary complex. The mixture of CDs interacted with each steroidal d... |
10726768 | Capillary electrophoresis behavior of water-soluble anionic porphyrins in the presence of beta-cyclodextrin and its O-methylated derivatives. | The electrophoretic behavior of water-soluble anionic porphyrins, such as meso-tetrakis(4-carboxyphenyl) porphyrin (TCPP), meso-tetrakis(4-sulfonatophenyl) porphyrin (TSPP) and its zinc(II) and copper(II) complexes (ZnTSPP and CuTSPP, respectively) has been studied by capillary zone electrophoresis using fused-silica c... |
10723794 | Cytoskeletal polarization and redistribution of cell-surface molecules during T cell antigen recognition. | T cell antigen recognition is accompanied by cytoskeletal polarization towards the APC and large-scale redistribution of cell surface molecules into 'supramolecular activation clusters' (SMACs), forming an organized contact interface termed the 'immunological synapse' (IS). Molecules are arranged in the IS in a microme... |
10723770 | Effect of cyclodextrin complexation on aqueous solubility and photostability of phenothiazine. | The effect of cyclodextrin (beta-CD, gamma-CD and substituted beta-CD derivatives) complexation on the solubility and photostability of phenothiazine (Ph) was compared. The phase solubility method was applied to calculate the stability constants of soluble 1:1 or 1:2 inclusion compounds formed between Ph and CDs. Photo... |
10716196 | Direct measurement of islet amyloid polypeptide fibrillogenesis by mass spectrometry. | A novel method for monitoring fibrillogenesis is developed and applied to the amyloidogenic peptide, islet amyloid polypeptide (IAPP). The approach, based on electrospray ionization mass spectrometry, is complementary to existing assays of fibril formation as it monitors directly the population of precursor rather than... |
10716194 | Cleaved antitrypsin polymers at atomic resolution. | Alpha1-antitrypsin deficiency, which can lead to both emphysema and liver disease, is a result of the accumulation of alpha1-antitrypsin polymers within the hepatocyte. A wealth of biochemical and biophysical data suggests that alpha1-antitrypsin polymers form via insertion of residues from the reactive center loop of ... |
10716186 | Proline inhibits aggregation during protein refolding. | The in vitro refolding of hen egg-white lysozyme is studied in the presence of various osmolytes. Proline is found to prevent aggregation during protein refolding. However, other osmolytes used in this study fail to exhibit a similar property. Experimental evidence suggests that proline inhibits protein aggregation by ... |
10716177 | Structure-based thermodynamic analysis of the dissociation of protein phosphatase-1 catalytic subunit and microcystin-LR docked complexes. | The relationship between the structure of a free ligand in solution and the structure of its bound form in a complex is of great importance to the understanding of the energetics and mechanism of molecular recognition and complex formation. In this study, we use a structure-based thermodynamic approach to study the dis... |
10713993 | Structural characterization of a methionine-rich, emulsifying protein from sunflower seed. | The 2 S seed storage protein, sunflower albumin 8, contains an unusually high proportion of hydrophobic residues including 16 methionines in a mature protein of 103 amino acids. A structural model, based on the known structure of a related protein, has been constructed as a four-helix bundle cross-linked by four disulp... |
10702881 | Topography of the 1:1 alpha-cyclodextrin-nitromethane inclusion complex. | Dissolution of alpha-cyclodextrin (alpha-CD) in 9:1 water-nitromethane smoothly generates the title compound, which crystallizes as the pentahydrate in the orthorhombic space group P2(1)2(1)2(1) with a = 9.452(4), b = 14.299(3), c = 37.380(10) A, and Z = 4. Its crystal structure analysis revealed the alpha-CD macrocycl... |
10702875 | Synthesis and silica-based immobilization of monofunctionalized cyclomaltoheptaose derivatives for enantioselective HPLC. | Heptakis(6-O-tert-butyldimethylsilyl-2,3-di-O-methyl)cyclomaltohep taose (6-TBDMS-2,3-Me-beta-CD) and heptakis(2,3,6-tri-O-methyl)cyclomaltoheptaose (per-Me-beta-CD) were monofunctionalized by introduction of a 5-cyanopentyl group attached to one of the O-2, O-3 or O-6 positions and subsequent reduction with lithium al... |
10701679 | Simultaneous stereoselective analysis of tramadol and its main phase I metabolites by on-line capillary zone electrophoresis-electrospray ionization mass spectrometry. | On-line combination of partial filling capillary electrophoresis and electrospray ionization mass spectrometry was demonstrated for the simultaneous enantioseparation of tramadol and its main phase I metabolites. The partial filling technique was efficient at avoiding MS contamination by the chiral selector. Different ... |
10701678 | Enantioseparation of atropine by capillary electrophoresis using sulfated beta-cyclodextrin: application to a plant extract. | A capillary zone electrophoresis (CZE) method, with sulfated beta-CD as chiral selector, was optimized by means of an experimental design for the enantioseparation of atropine. In this study, a central composite design was used and the following factors were varied simultaneously: buffer concentration, buffer pH and su... |
10681465 | The gene coding for the Hrp pilus structural protein is required for type III secretion of Hrp and Avr proteins in Pseudomonas syringae pv. tomato. | Bacterial surface appendages called pili often are associated with DNA and/or protein transfer between cells. The exact function of pili in the transfer process is not understood and is a matter of considerable debate. The Hrp pilus is assembled by the Hrp type III protein secretion system of Pseudomonas syringae pv. t... |
10681431 | The xeroderma pigmentosum group C gene leads to selective repair of cyclobutane pyrimidine dimers rather than 6-4 photoproducts. | We investigated the contribution of the xeroderma pigmentosum group C (XPC) gene to DNA repair. We stably transfected XPC cells (XP4PA-SV-EB) with XPC cDNA and selected a partially corrected (XP4PA-SE1) and a fully corrected (XP4PA-SE2) clone. Cell survival after UVC (254 nm) exposure was low for XP4PA-SV-EB, intermedi... |
10688877 | Quantitative analysis of the effect of the mutation frequency on the affinity maturation of single chain Fv antibodies. | Random mutagenesis and selection using phage or cell surface display provides an efficient method for affinity maturation of single chain Fv (scFv) antibodies, thereby improving function in various applications. To investigate the effects of mutation frequency on affinity maturation, error-prone PCR was used to generat... |
10691699 | Acyclic analogues of deoxyadenosine 3',5'-bisphosphates as P2Y(1) receptor antagonists. | P2Y(1) receptors are activated by ADP and occur on endothelial cells, smooth muscle, epithelial cells, lungs, pancreas, platelets, and in the central nervous system. With the aid of molecular modeling, we have designed nucleotide analogues that act as selective antagonists at this subtype. The present study has tested ... |
10691648 | Study of interactions between food phenolics and aromatic flavors using one- and two-dimensional (1)H NMR spectroscopy. | Changes in flavor release and aroma characteristics in a medium including food phenolics may be attributed to an intermolecular interaction between flavor compounds and phenolics. To investigate the interaction, one- and two-dimensional NMR studies have been carried out on the binding of two phenolics, gallic acid and ... |
10689668 | Matrix-assisted laser desorption/ionization mass spectrometry, enzymatic digestion, and molecular modeling in the study of nonenzymatic glycation of IgG. | The glycation-induced functional change of immunoglobulins is of particular interest. The glycation levels of IgG in 10 healthy subjects and 20 diabetic patients with different degrees of metabolic control were studied by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. It reveals the number of gl... |
10688757 | Comparative effects of (SBE)7m-beta-CD and HP-beta-CD on the stability of two anti-neoplastic agents, melphalan and carmustine. | The purpose of this study was to evaluate and compare the potential use of two parenterally safe beta-cyclodextrins derivatives, (SBE)7m-beta-CD and HP-beta-CD, as solubilizers and stabilizers for melphalan and carmustine, two very unstable antineoplastic agents. Phase solubility and chemical stability of the compounds... |
10688755 | Kinetic study of a 2-hydroxypropyl-beta-cyclodextrin-based formulation of all-trans-retinoic acid in Sprague-Dawley rats after oral or intravenous administration. | all-trans-Retinoic acid (ATRA, vitamin A acid, or tretinoin) is a potent chemotherapeutic agent for the treatment of acute promyelocytic leukemia (APL). Its poor aqueous solubility not only affects its oral absorption but also prevents it from forming an aqueous parenteral formulation. Recently, we developed a water-so... |
10688753 | Cyclodextrin-catalyzed deacetylation of spironolactone is pH and cyclodextrin dependent. | The complexation of spironolactone (SP) with cyclodextrins (CDs) and the effect of pH on the CD catalyzed deacetylation of SP was studied in the presence of beta-cyclodextrin (beta-CD), hydroxypropyl-beta-cyclodextrin (HP-beta-CD), sulfobutylether-beta-cyclodextrin ([SBE](7m)-beta-CD), gamma-cyclodextrin (gamma-CD), an... |
10684254 | Induction of caveolae in the apical plasma membrane of Madin-Darby canine kidney cells. | In this paper, we have analyzed the behavior of antibody cross-linked raft-associated proteins on the surface of MDCK cells. We observed that cross-linking of membrane proteins gave different results depending on whether cross-linking occurred on the apical or basolateral plasma membrane. Whereas antibody cross-linking... |
10686279 | Stereodifferentiation of 3-hydroxyisobutyric- and 3-aminoisobutyric acid in human urine by enantioselective multidimensional capillary gas chromatography-mass spectrometry. | The chiral metabolites 3-hydroxyisobutyric acid (HIBA) and 3-aminoisobutyric acid (AIBA) are intermediates in the pathways of L-valine and thymine and play an important role in the diagnosis of the very rare inherited metabolic diseases 3-hydroxyisobutyric aciduria (McKusick 236975) and methylmalonic semialdehyde dehyd... |
10684602 | Residues in Cdc42 that specify binding to individual CRIB effector proteins. | Cdc42 is a member of the Rho family of small G proteins. Signal transduction events emanating from Cdc42 lead to cytoskeletal rearrangements, cell proliferation, and cell differentiation. Many effector proteins have been identified for Cdc42; however, it is not clear how certain effectors specifically recognize and bin... |
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