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9025262 | Approach to the thermodynamics of enantiomer separation by gas chromatography. Enantioselectivity between the chiral inhalation anesthetics enflurane, isoflurane and desflurane and a diluted gamma-cyclodextrin derivative. | The thermodynamics of enantioselectivity, -delta D,L(delta G), -delta D,L(delta H), delta D,L(delta S) and Tiso, have been determined by gas chromatography employing the concept of the retention increment R' for the inhalation anesthetics enflurane (1), isoflurane (2) and desflurane (3) and the selector octakis(3-O-but... |
9024191 | Intravenous carbamazepine: comparison of different parenteral formulations in a mouse model of convulsive status epilepticus. | <h4>Purpose</h4>A drawback of carbamazepine (CBZ), a major antiepileptic drug (AED) with clinical efficacy against partial and generalized convulsive seizures, is its isolubility in aqueous vehicles, which is generally considered a contraindication to parenteral administration in epileptic patients. However, CBZ can be... |
9120769 | Intestinal safety of water-soluble beta-cyclodextrins in paediatric oral solutions of spironolactone: effects on human intestinal epithelial Caco-2 cells. | Effects of water-soluble beta-cyclodextrins (beta CDs) on intestinal epithelial integrity were investigated, to establish the safe use of these beta CDs as solubilizers of spironolactone in paediatric enteral solutions. Mannitol permeability and transepithelial resistance (TER) of human intestinal epithelial Caco-2 cel... |
9020480 | Somatostatin receptor subtype mRNA expression in human colorectal cancer and normal colonic mucosae. | Somatostatin analogues may be useful novel agents in the systemic treatment of advanced colorectal cancer, as somatostatin inhibits proliferation in a wide variety of cell types. Here, we report the expression profiles of somatostatin receptor mRNAs in 32 pairs of malignant and normal colonic epithelia. Receptor subtyp... |
9017593 | In vitro reconstitution of a heterotrimeric nucleoporin complex consisting of recombinant Nsp1p, Nup49p, and Nup57p. | The yeast nucleoporins Nsp1p, Nup49p, and Nup57p form a complex at the nuclear pores which is involved in nucleocytoplasmic transport. To investigate the molecular basis underlying complex formation, recombinant full-length Nup49p and Nup57p and the carboxyl-terminal domain of Nsp1p, which lacks the FXFG repeat domain,... |
9016561 | Transcription activation at class II CRP-dependent promoters: the role of different activating regions. | Transcription activation by the Escherichia coli cyclic AMP receptor protein (CRP) at Class II promoters is dependent on direct interactions between two surface-exposed activating regions (AR1 and AR2) and two contact sites in RNA polymerase. The effects on transcription activation of disrupting either AR1 or AR2 have ... |
9016551 | MHCPEP, a database of MHC-binding peptides: update 1996. | MHCPEP is a curated database comprising over 9000 peptide sequences known to bind MHC molecules. Entries are compiled from published reports as well as from direct submissions of experimental data. Each entry contains the peptide sequence, its MHC specificity and, when available, experimental method, observed activity,... |
9016876 | Estrogen protects lenses against cataract induced by transforming growth factor-beta (TGFbeta). | Cataract, already a major cause of visual impairment and blindness, is likely to become an increasing problem as the world population ages. In a previous study, we showed that transforming growth factor-beta (TGFP) induces rat lenses in culture to develop opacities and other changes that have many features of human sub... |
9016337 | Diltiazem-like calcium entry blockers: a hypothesis of the receptor-binding site based on a comparative molecular field analysis model. | A series of 26 pyrrolo[2,1-c][1,4]benzothiazines, which have been already synthesized and reported to show calcium antagonist activity in both radioligand-binding assays and functional studies, were investigated using the comparative molecular field analysis (CoMFA) paradigm. Due to the lack of experimental structural ... |
9015315 | Abnormal compartmentalization of cartilage matrix components in mice lacking collagen X: implications for function. | There are conflicting views on whether collagen X is a purely structural molecule, or regulates bone mineralization during endochondral ossification. Mutations in the human collagen alpha1 (X) gene (COL10A1) in Schmid metaphyseal chondrodysplasia (SMCD) suggest a supportive role. But mouse collagen alpha1 (X) gene (Col... |
9013809 | Sustained release of flufenamic acid from a drug-triacetyl-beta-cyclodextrin complex. | Triacetyl-beta-cyclodextrin (TA-beta-CyD), a hydrophobic cyclodextrin derivative that is insoluble in water, was used to form a complex with flufenamic acid (FA). Complexes of FA with TA-beta-CyD (FA-TA-beta-CyD) at various molar ratios (1:1, 1:2, 1:3) were prepared by a kneading method, using ethanol as a solvent. FA-... |
9012849 | Identification of a structural constituent and one possible site of postembryonic formation of a teleost otolithic membrane. | A gelatinous otolithic membrane (OM) couples a single calcified otolith to the sensory epithelium in the bluegill sunfish (Lepomis macrochirus) saccule, one of the otolithic organs in the inner ear. Though the OM is an integral part of the anatomic network of endorgan structures that result in vestibular function in th... |
9012809 | The thioredoxin binding domain of bacteriophage T7 DNA polymerase confers processivity on Escherichia coli DNA polymerase I. | Bacteriophage T7 DNA polymerase shares extensive sequence homology with Escherichia coli DNA polymerase I. However, in vivo, E. coli DNA polymerase I is involved primarily in the repair of DNA whereas T7 DNA polymerase is responsible for the replication of the viral genome. In accord with these roles, T7 DNA polymerase... |
9012804 | Major proteinase movement upon stable serpin-proteinase complex formation. | To determine whether formation of the stable complex between a serpin and a target proteinase involves a major translocation of the proteinase from its initial position in the noncovalent Michaelis complex, we have used fluorescence resonance energy transfer to measure the separation between fluorescein attached to a s... |
9012796 | In vitro scanning saturation mutagenesis of an antibody binding pocket. | We have combined PCR mutagenesis with in vitro transcription/translation and ELISA for the rapid generation and characterization of antibody mutants. The PCR products are used directly as the template for the in vitro transcription/translation reactions and because no cloning steps are required, the in vitro saturation... |
9012790 | The dynamins: redundant or distinct functions for an expanding family of related GTPases? | In the 7 years since dynamin was first isolated from bovine brain in search of novel microtubule-based motors, our understanding of this enzyme has expanded significantly. We now know that brain dynamin belongs to a family of large GTPases, which mediate vesicle trafficking. Furthermore, this enzymatic activity is mark... |
9010638 | Substituent elimination from p-substituted phenols by cytochrome P450. ipso-Substitution by the oxygen atom of the active species. | When various p-substituted phenols (substituent = NO2, CN, CH2OH, COCH3, COPh, COOH, F, Cl, and Br) were incubated with rat liver microsomes, the substituent was eliminated to produce hydroquinone, and the reaction was inhibited by CO and a cytochrome P450-specific inhibitor. In the case of p-cresol (substituent = CH3)... |
9010470 | Analysis of localization of adult T-cell leukemia-derived factor in the transient ischemic rat retina after treatment with OP-1206 alpha-CD, a prostaglandin E1 analogue. | Prostaglandin E1 (PGE1) is commonly used in therapy for obstructive diseases, including ischemic retinopathy, in which pathogenetic reactive oxygen intermediates are responsible. However, the mechanism(s) of PGE1 in reducing tissue damage is still unclear. Adult T-cell leukemia-derived factor/human thioredoxin (ADF) is... |
9009264 | Differential targeting of closely related ECM glycoproteins: the pherophorin family from Volvox. | The alga Volvox carteri represents one of the simplest multicellular organisms. Its extracellular matrix (ECM) is modified under developmental control, e.g. under the influence of the sex-inducing pheromone that triggers development of males and females at a concentration below 10(-16) M. A novel ECM glycoprotein (pher... |
9008701 | Chromosomes with two intact axial cores are induced by G2 checkpoint override: evidence that DNA decatenation is not required to template the chromosome structure. | Here we report that DNA decatenation is not a physical requirement for the formation of mammalian chromosomes containing a two-armed chromosome scaffold. 2-aminopurine override of G2 arrest imposed by VM-26 or ICRF-193, which inhibit topoisomerase II (topo II)-dependent DNA decatenation, results in the activation of p3... |
9007979 | The crystal structure of the designed trimeric coiled coil coil-VaLd: implications for engineering crystals and supramolecular assemblies. | The three-dimensional structure of the 29-residue designed coiled coil having the amino acid sequence acetyl-E VEALEKK VAALESK VQALEKK VEALEHG-amide has been determined and refined to a crystallographic R-factor of 21.4% for all data from 10-A to 2.1-A resolution. This molecule is called coil-VaLd because it contains v... |
9007978 | Molecular modeling of the structures of human and rat pancreatic cholesterol esterases. | Structural models have been generated for rat and human cholesterol esterases by molecular modeling. For rat cholesterol esterase, three separate models were generated according to the following procedure: (1) the cholesterol esterase sequence was aligned with those of three template enzymes: Torpedo californica acetyl... |
9003434 | The human ENO1 gene product (recombinant human alpha-enolase) displays characteristics required for a plasminogen binding protein. | Plasminogen binds with low affinity in a lysine-dependent manner to many cell types. Previously, a 54 kDa plasminogen receptor found on the surface of U-937 cells was identified as an alpha-enolase-like molecule. The aims of this study were to determine whether recombinant alpha-enolase (r-alpha-enolase), encoded by EN... |
9002462 | Nuclear magnetic resonance investigations of the inclusion complexation of gliclazide with beta-cyclodextrin. | The formation of the gliclazide-beta-cyclodextrin (GL-beta-CD) inclusion compound has been studied in the liquid state by phase solubility techniques and by 1H and 13C NMR spectroscopy. From the initial straight portion of the solubility curve (Bs type), the value of the apparent stability constant (Kc) was calculated ... |
9002438 | Environmental effects of heavy spillage from a destroyed pesticide store near Hargeisa (Somaliland) assessed during the dry season, using reptiles and amphibians as bioindicators. | A pesticide store near Hargeisa (Somaliland) was damaged by bombing in May 1988, and subsequently looted by local people, who removed and drained drums of chemicals. Assessment of the effects of resultant spillage during the dry season, March/April 1993, established that pesticides, mainly organochlorines (dieldrin and... |
9002213 | Förster energy transfer in ultrathin polymer layers as a basis for biosensors. | A method of detecting the binding of analyte molecules to biospecific receptors, like antibodies, is described. Förster energy transfer is used in connection with monomolecular organic films. The films are built up from pre-polymerized materials using the Langmuir-Blodgett or self-assembly techniques. Fluorescent dyes ... |
9002209 | Nucleic acid based sensors. | Nucleic acids may be analyte or molecular recognition elements in biosensors. Both aspects merge in the genosensor approach, where detection of special sequences is facilitated by hybridization of a target nucleic acid to a complementary immobilized template. All three roles of nucleic acids in biosensors are discussed... |
9002205 | Imprinting techniques in synthetic polymers--new options for chemosensors. | Highly selective molecular recognition in synthetic polymers may be the basis for a new type of chemosensor. For the preparation of such polymers, a molecular imprinting procedure during crosslinking is used to generate, with the aid of template molecules, microcavities of specific shape and with a defined arrangement ... |
9002079 | Comparison of the safety of early enteral vs parenteral nutrition in mild acute pancreatitis. | <h4>Background</h4>This prospective study was designed to compare the safety, efficacy, cost, and impact on patient outcome of early total enteral nutrition (TEN) vs total parenteral nutrition (TPN) in acute pancreatitis.<h4>Methods</h4>Patients admitted with acute pancreatitis or an acute flare of chronic pancreatitis... |
9001397 | Block of ShakerB K+ channels by Pi1, a novel class of scorpion toxin. | Here we describe the basic features of the interaction of K+ channels with Pi1, a recently described 35 amino acid scorpion toxin, which has four disulfide bridges instead of the three commonly found in all the other known scorpion toxins. We found that: (a) Pi1 blocks ShakerB from the outside with a 1:1 stoichiometry,... |
9001289 | The regional production of cytokines and lactate in sepsis-related multiple organ failure. | In order to explore whether an organ-specific pattern in cytokine and lactate concentrations exists in patients with multiple organ failure (MOF), we measured the cytokines interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor-alpha (TNF-alpha), and lactate in blood taken from the hepatic vein, pulmonary capill... |
9000055 | Biochemical characterization of a molecular switch involving the heat shock protein ClpC, which controls the activity of ComK, the competence transcription factor of Bacillus subtilis. | Development of genetic competence in Bacillus subtilis is controlled by the competence-specific transcription factor ComK. ComK activates transcription of itself and several other genes required for competence. The activity of ComK is controlled by other genes including mecA, clpC, and comS. We have used purified ComK,... |
8995524 | Differential binding of S-adenosylmethionine S-adenosylhomocysteine and Sinefungin to the adenine-specific DNA methyltransferase M.TaqI. | The crystal structures of the binary complexes of the DNA methyltransferase M.TaqI with the inhibitor Sinefungin and the reaction product S-adenosyl-L-homocysteine were determined, both at 2.6 A resolution. Structural comparison of these binary complexes with the complex formed by M.TaqI and the cofactor S-adenosyl-L-m... |
9011564 | Bacterial infection induces nitric oxide synthase in human neutrophils. | The identification of human inflammatory cells that express inducible nitric oxide synthase and the clarification of the role of inducible nitric oxide synthase in human infectious or inflammatory processes have been elusive. In neutrophil-enriched fractions from urine, we demonstrate a 43-fold increase in nitric oxide... |
8994636 | 19F NMR measurements of the rotational mobility of proteins in vivo. | Three glycolytic enzymes, hexokinase, phosphoglycerate kinase, and pyruvate kinase, were fluorine labeled in the yeast Saccharomyces cerevisiae by biosynthetic incorporation of 5-fluorotryptophan. 19F NMR longitudinal relaxation time measurements on the labeled enzymes were used to assess their rotational mobility in t... |
8994631 | Atomic force microscope imaging contrast based on molecular recognition. | The contrast in atomic force microscope images arises from forces between the tip and the sample. It was shown recently that specific molecular interaction forces may be measured with the atomic force microscope; consequently, we use such forces to map the distribution of binding partners on samples. Here we demonstrat... |
8994624 | Mesoscopic gels at low agarose concentration: perturbation effects of ethanol. | Aqueous agarose solutions at low concentrations (0.5 g/liter) were temperature quenched below the spinodal line to form mutually disconnected mesoscopic gels. In the presence of 6% ethanol, these solutions, obtained by quenching at the same temperature depth as in pure water, appear much more fluid, as determined by pr... |
8994622 | Triplet state magnetic resonance and fluorescence spectroscopy of metal-substituted hemoglobins. | Fluorescence detected magnetic resonance (FDMR) spectra detected at 596 nm of zinc-substituted hemoglobins at 4.2 K show a split D-E transition, which is not observed for zinc protoporphyrins ligated by methylimidazole in glasses. Incorporation of the zinc heme into the globin pocket is also accompanied by a blue shift... |
8994621 | Bound ligand motion in crystalline carboxypeptidase A. | Deuterium NMR spectra for the phenyl ring deuterons have been obtained for D-phenylalanine, L-phenylalanine, phenylacetic acid, and phenyl propionic acid in randomly oriented crystals of carboxypeptidase A as a function of water content. The spectra are analyzed using a two-site jump model for phenyl ring pi-flips when... |
8994620 | Solvent hydrogen-bond network in protein self-assembly: solvation of collagen triple helices in nonaqueous solvents. | Forces between type I collagen triple helices are studied in solvents of varying hydrogen-bonding ability. The swelling of collagen fibers in reconstituted films is controlled by the concentration of soluble polymers that are excluded from the fibers and that compete osmotically with collagen for available solvent. The... |
8994616 | Redox effects on the excited-state lifetime in chlorosomes and bacteriochlorophyll c oligomers. | Oligomers of [E,E] BChl CF (8, 12-diethyl bacteriochlorophyll c esterified with farnesol (F)) and [Pr,E] BChl CF (analogously, M methyl, Pr propyl) in hexane and aqueous detergent or lipid micelles were studied by means of steady-state absorption, time-resolved fluorescence, and electron spin resonance spectroscopy. Th... |
8994606 | Hindered transport of macromolecules in isolated glomeruli. II. Convection and pressure effects in basement membrane. | The filtration rates for water and a polydisperse mixture of Ficoll across films of isolated glomerular basement membrane (GBM) were measured to characterize convective transport across this part of the glomerular capillary wall. Glomeruli were isolated from rat kidneys and the cells were removed by detergent lysis, le... |
8994595 | The structure and organization of synthetic putative membranous segments of ROMK1 channel in phospholipid membranes. | The hydropathy plot of ROMK1, an inwardly rectifying K+ channel, suggests that the channel contains two transmembrane domains (M1 and M2) and a linker between them with significant homology to the H5 pore region of voltage-gated K+ channels. To gain structural information on the pore region of the ROMK1 channel, we use... |
8994593 | Charge density-dependent strength of hydration and biological structure. | Small ions of high charge density (kosmotropes) bind water molecules strongly, whereas large monovalent ions of low charge density (chaotropes) bind water molecules weakly relative to the strength of water-water interactions in bulk solution. The standard heat of solution of a crystalline alkali halide is shown here to... |
8993858 | Yersinia pestis--etiologic agent of plague. | Plague is a widespread zoonotic disease that is caused by Yersinia pestis and has had devastating effects on the human population throughout history. Disappearance of the disease is unlikely due to the wide range of mammalian hosts and their attendant fleas. The flea/rodent life cycle of Y. pestis, a gram-negative obli... |
8990399 | Analysis of bacteriophage N protein and peptide binding to boxB RNA using polyacrylamide gel coelectrophoresis (PACE). | The antitermination protein N from bacteriophage lambda (Nlambda) interacts with the nut site in its own mRNA, as well as host factors, to facilitate formation of a termination-resistant transcription complex. The conserved, amino-terminal arginine-rich domain of Nlambda protein is known to interact with a small RNA ha... |
8990205 | Functional expression of a novel human neurokinin-3 receptor homolog that binds [3H]senktide and [125I-MePhe7]neurokinin B, and is responsive to tachykinin peptide agonists. | In 1992, Xie et al. identified a cDNA sequence in the expression cloning search for the kappa opioid receptor. When the cDNA was expressed in Cos-7 cells, binding of opioid compounds was observed to be of low affinity and without kappa, mu, or delta selectivity [Xie, G.-X., Miyajima, A. and Goldstein, A. (1992) Proc. N... |
8990154 | Direct conversion of an oligopeptide from a beta-sheet to an alpha-helix: a model for amyloid formation. | A 16-amino acid oligopeptide forms a stable beta-sheet structure in water. In physiological solutions it is able to self-assemble to form a macroscopic matrix that stains with Congo red. On raising the temperature of the aqueous solution above 70 degrees C, an abrupt structural transition occurs in the CD spectra from ... |
8985385 | In vitro interactions of the aphid endosymbiotic SymL chaperonin with barley yellow dwarf virus. | Barley yellow dwarf virus (BYDV)-vector relationships suggest that there are specific interactions between BYDV virions and the aphid's cellular components. However, little is known about vector factors that mediate virion recognition, cellular trafficking, and accumulation within the aphid. Symbionins are molecular ch... |
8985375 | Approaches to determine stoichiometry of viral assembly components. | Due to the rapidity of biological reactions, it is difficult to isolate intermediates or to determine the stoichiometry of participants in intermediate reactions. Instead of determining the absolute amount of each component, this study involved the use of relative parameters, such as dilution factors, percentages proba... |
8985358 | Antioxidant-induced changes of the AP-1 transcription complex are paralleled by a selective suppression of human papillomavirus transcription. | Considering the involvement of a redox-regulatory pathway in the expression of human papillomaviruses (HPVs), HPV type 16 (HPV-16)-immortalized human keratinocytes were treated with the antioxidant pyrrolidine-dithiocarbamate (PDTC). PDTC induces elevated binding of the transcription factor AP-1 to its cognate recognit... |
8985356 | Posttranscriptional regulation of hepatitis B virus replication by the precore protein. | Hepadnaviruses encode two core-related open reading frames. One directs the synthesis of the p21 core protein, which subsequently becomes a structural component of the viral nucleocapsid. The other produces a p25 precore protein that is targeted by a signal peptide to a cell secretory pathway where N-terminal processin... |
8985355 | Function of the human T-cell leukemia virus type 1 21-base-pair repeats in basal transcription. | The human T-cell leukemia virus type 1 (HTLV-1) promoter contains three copies of an imperfect 21-bp repeat called Tax-responsive element (TRE1). To examine the role of individual TRE1 sequences in basal transcription of the HTLV-1 promoter, site-directed mutations were generated in all possible combinations of one, tw... |
8985351 | Genetic diversity of simian immunodeficiency viruses from West African green monkeys: evidence of multiple genotypes within populations from the same geographical locale. | High simian immunodeficiency virus (SIV) seroprevalence rates have been reported in the different African green monkey (AGM) subspecies. Genetic diversity of these viruses far exceeds the diversity observed in the other lentivirus-infected human and nonhuman primates and is thought to reflect ancient introduction of SI... |
8985322 | Dose-dependent regulation of the early promoter of human papillomavirus type 18 by the viral E2 protein. | The activity of the E6/E7 promoter of genital human papillomaviruses (HPVs) is positively and negatively modulated by a complex interplay between a variety of cellular transcription factors and the virally encoded E2 protein. The long control region of genital HPVs contains four E2 binding sites in conserved positions,... |
8980767 | Evaluation of a brain-targeting zidovudine chemical delivery system in dogs. | AIDS encephalopathy is an insidious complication of human immunodeficiency virus infection which is difficult to treat because of the poor uptake of many potentially useful antiretroviral drugs through the blood-brain barrier. A chemical delivery system (CDS) for zidovudine (AZT) based on redox trapping within the brai... |
8980750 | T-8581, a new orally and parenterally active triazole antifungal agent: in vitro and in vivo evaluations. | T-8581 is a new water-soluble triazole antifungal agent. The geometric mean IC80s (GM-IC80S; where the IC80 is the lowest drug concentration which reduced the optical density at 630 nm by 80% compared with the optical density at 630 nm of the drug-free control) for Candida albicans were as follows: T-8581, 0.218 microg... |
8980747 | Comparison of voriconazole (UK-109,496) and itraconazole in prevention and treatment of Aspergillus fumigatus endocarditis in guinea pigs. | Left-sided Aspergillus fumigatus endocarditis was established in the guinea pig heart by catheterization and inoculation with conidia via a tributary of the femoral vein. This animal model was used to compare the efficacy of the triazole antifungal agents voriconazole (UK-109,496) and itraconazole. In the prophylaxis e... |
8979346 | Stable expression of pertussis toxin in Bordetella bronchiseptica under the control of a tightly regulated promoter. | Pertussis toxin (PT) is an essential component of accellular vaccines against whooping cough. However, the industrial production of PT from Bordetella pertussis is impaired by slow growth and poor yields. To overcome these problems, we have constructed a minitransposon containing the tox operon under the control of a t... |
8975907 | The novel cuticular collagen Ovcol-1 of Onchocerca volvulus is preferentially recognized by immunoglobulin G3 from putatively immune individuals. | The cDNA sequence encoding an Onchocerca volvulus collagen, Ovcol-1, has been isolated and the corresponding native antigen has been identified. The cDNA encodes an open reading frame of 96 amino acid residues containing an uninterrupted 66-residue Gly-X-Y repeat triple-helical (TH) domain (where X and Y may be any ami... |
8972198 | The activity of the scs and scs' insulator elements is not dependent on chromosomal context. | Sequence elements that protect a reporter gene from chromosomal position effects or that block enhancer-activated transcription are called insulators. Using a plasmid-based microinjection assay with Xenopus laevis oocytes, we show that the heterologous Drosophila melanogaster scs and scs' insulator elements do not requ... |
8968874 | Human papillomavirus type 16 sequence variants: identification by E6 and L1 lineage-specific hybridization. | A catalog of human papillomavirus (HPV) type 16 (HPV-16) E6 and L1 signature nucleotides was used to develop PCR-based oligonucleotide probe systems capable of distinguishing HPV-16 class and subclass variants. Twenty-three E6-specific oligonucleotide probes targeting 13 variant nucleotide positions and 12 L1-specific ... |
8959671 | The pulmonary surfactant system: biochemical and clinical aspects. | This article starts with a brief account of the history of research on pulmonary surfactant. We will then discuss the morphological aspects and composition of the pulmonary surfactant system. We describe the hydrophilic surfactant proteins A and D and the hydrophobic surfactant proteins B and C, with focus on the cruci... |
9731389 | Development of a fuzzy logic based system to monitor the electrical responses of nerve fiber. | A fuzzy logic based control system to monitor and control the electrical and chemical responses of nerve fibers has been designed and simulated. Fuzzy logic provides powerful reasoning mechanisms for combining information from multiple fuzzy sets.... The rule base has been developed based on the difference between the ... |
9676265 | I-symmetry, the highest chiral point group, and the icosahedral structure of virus particles. | Small molecules exhibiting I-symmetry, the member of highest order amongst the five chiral point groups, have yet to be made. However, many virus particles such as the human adenovirus exhibit icosahedral symmetry. The handedness of the subunits being exchanged or permutated by symmetry operations in these supramolecul... |
9672621 | beta-Cyclodextrin derivatives as carriers to enhance the antiviral activity of an antisense oligonucleotide directed toward a coronavirus intergenic consensus sequence. | The ability of cyclodextrins to enhance the antiviral activity of a phosphodiester oligodeoxynucleotide has been investigated. A 18-mer oligodeoxynucleotide complementary to the initiation region of the mRNA coding for the spike protein and containing the intergenic consensus sequence of an enteric coronavirus has been... |
9672617 | Molecular characterization of morphologically typical human calicivirus Sapporo. | Human calicivirus Sapporo (SV) has typical calicivirus morphology and causes acute gastroenteritis in children. The nucleotide sequence of 3.2 kb of the 3' end of SV was determined from a cloned cDNA. The 3' end of the SV genome is predicted to encode the RNA-dependent RNA polymerase region, the capsid protein and two ... |
9619419 | The use of congo red as a lyotropic liquid crystal to carry stains in a model immunotargeting system--microscopic studies. | The lyotropic liquid crystal dye-Congo Red was used as a carrier in a model immunotargeting system constructed from sheep red blood cells (SRBC) representing the antigen target and rabbit IgG anti-SRBC as the specific driving immunoglobulin. Rhodamine B and Hemin stains were chosen as example chemicals carried to the t... |
9620218 | Expression and purification of single-chain anti-HBx antibody in Escherichia coli. | Monoclonal antibodies have been widely used in tumor targeting studies with promising results. However, their clinical application has been limited by heterogeneity and macro-molecular movement of murine antibody. In this study, the variable-region (heavy- and light-chain) fragments of anti-HBx monoclonal antibody were... |
9615310 | Fungitoxic activity of some cytochalasins and their derivatives on Phytophthora species. | The activity of cytochalasin B was tested on 8 Phytophthora species, while the same toxin, some of its derivatives and natural analogues, namely cytochalasin F and deoxaphomin, were assayed at 2 x 10(-5) - 2 x 10(-4) M on the most sensitive species, P. cactorum. A significant inhibitory activity on P. cactorum was show... |
9587382 | [Early cell response to radiation]. | The early steps of cellular radiation response have been investigated using a linear electron accelerator operated in a split-dose mode, in such a way that the time intervals between pulse exposures to relativistic electrons ranged from fractions of a second to a few minutes. The initial dose brought about large, synch... |
9586126 | Analytical application of host-guest chemistry using in vitro selection. | A new bioassay system using oligodeoxyribonucleotides (DNAs) obtained by the in vitro selection method, instead of antibodies, is described. The DNAs which selectively bind to target molecules, folic acid, and thyroxine (T4), were selected. The DNAs were labeled with biotin or fluorescent molecules and the labeled DNA ... |
9586124 | Selective recognition of tandemly repeated DNA sequences by homo- and heterodimers of short peptides. | The non-covalent and specific protein-protein interaction is critical to the specificity and the cooperativity of the DNA-binding by protein dimers. We have designed and synthesized three sets of peptide dimers with covalent- or noncovalent artificial dimerization modules to elucidate the structural and thermodynamic a... |
9586074 | Homogeneous catalyst for DNA hydrolysis (4). Efficient DNA hydrolysis by lanthanide--saccharide complexes. | Homogeneous and neutral solutions are prepared by mixing Ce(NH4)2(NO3)6 with either isomaltose, melibiose, gentiobiose, palatinose, mannitol, sorbitol, galactitol, or glucamine in pH 7 hepes buffer ([Ce(IV)]0/[monomeric residue of saccharide]0 = 1). In contrast, amylose, cyclodextrins, maltose, glucose, and fructose pr... |
9586043 | Parallel-stranded duplexes and quartet assemblies formed by oligonucleotides containing isoguanine. | Oligonucleotides with isoguanine-cytosine base pairs form duplexes with parallel chain orientation. This strong base pair dictates the strand polarity when additional dA-dT or N7Ad-dT pairs are present. The same is observed for the isocytosine-guanine pair. Quartet structures are built by the self-assembly of oligonucl... |
9586030 | Recognition of tRNA(Gly) by three widely diverged glycyl-tRNA synthetases: evolution of tRNA recognition. | Glycyl-tRNA synthetase (GlyRS) is an unusual aminoacyl-tRNA synthetase because it varies in its quarternary structure between organisms; Escherichia coli GlyRS is an alpha 2 beta 2 tetramer, whereas those of Thermus thermophilus and yeast are alpha 2 dimers. In contrast, the tRNA(Gly) sequence is virtually identical in... |
9574124 | [Acute renal failure]. | Acute renal failure is defined as a multifactorial syndrome that occurs--depending of definition and selection of patients--in 2%-25% of all ICU patients. Most frequent in surgery (approximately 70%), ARF is caused by septic complications. Renal replacement therapy is managed today by dialysis, hemofiltration or the co... |
29711431 | The First Coordinatively Saturated, Quadruply Stranded Helicate and Its Encapsulation of a Hexafluorophosphate Anion. | Incarcerated in a helical prison: The encapsulation of a PF<sub>6</sub><sup>-</sup> ion within a quadruply stranded helicate (shown schematically) results from the self-assembly of four molecules of 1,4-bis(3-pyridyloxy)benzene and two Pd<sup>II</sup> ions. This represents not only the first example of a coordinatively... |
29711426 | Modeling the Supramolecular Properties of Aliphatic-Aromatic Hydrocarbons with Convex-Concave Topology. | The molecular tweezers 1 a and 1 b have an electrostatic potential on the concave sides of the molecule which is surprisingly negative for hydrocarbons. According to semiempirical calculations this is a general phenomenon in nonconjugated π-electron systems with concave-convex topology, and it explains the receptor pro... |
29711424 | Electrostatic Control of Intramolecular Electron Transfer in Calix[4]diquinones Bearing an Appended Chromophore. | Binding of K<sup>+</sup> or Ba<sup>2+</sup> ions attenuates intramolecular electron transfer between a chromophore and an electron-affinic macrocyclic receptor (see schematic representation), and simultaneously amplifies luminescence. In the complexed state, photons absorbed by the dicationic chromophore are emitted as... |
29711422 | Investigation of the Molecular Recognition of Amino Acids by Cyclopeptides with Reflectometric Interference Spectroscopy. | IR spectroscopic mapping of resin beads allows destruction-free characterization of polymer-bound combinatorial compound libraries. By choice of different absorptions for IR reconstruction, resin beads with common structural elements can be "fished out" of a library and statistically investigated. |
29711420 | Highly Efficient Synthesis of Covalently Cross-Linked Peptide Helices by Ring-Closing Metathesis. | Olefin metathesis has been successfully applied to the synthesis of macrocyclic helical peptides [Eq. (a)]. Carbon-carbon bond tethers between amino acid side chains were introduced by ring-closing metathesis. This macrocyclization protocol is a novel and mild procedure for introducing nonnative covalent cross-links in... |
29711410 | Dendritic Pseudorotaxanes. | Self-organization is the key. A series of dendritic pseudorotaxanes were efficiently constructed from complementary building blocks-namely, a three-armed, triply charged ammonium salt and the first, second, and third generations of benzyl ether dendrons bearing the dibenzo[24]crown-8 moiety. The pseudorotaxane arising ... |
29711408 | Cross-Section Molecular Imaging of Supramolecular Microtubes with Contact Atomic Force Microscopy. | Bent molecules, distorted layers, columnar domains, and tube membranes (shown schematically in the picture): These hierarchical layers were directly visualized by contact atomic force microscopy along the long axes of the molecules aligned within microtubes made up of bolaamphiphile 1 by self-assembly. |
29711407 | Nucleic Acid Nanostructures and Topology. | Knots, polyhedra, and Borromean rings with specific structural and topological features can be made from DNA. Biotechnologists have been exploiting the programmability of DNA intermolecular associations for a quarter of a century. These operations have now been applied successfully to branched DNA species to produce co... |
29711405 | Kinetic and Thermodynamic Control in Self-Assembly: Sequential Formation of Linear and Circular Helicates. | NMR and MS analysis as a function of time has shown that the self-assembly of a linear ligand with Fe<sup>2+</sup> or Ni<sup>2+</sup> , metal ions of octahedral coordination geometry, generates first a triple helicate and thereafter the circular helicate 1 as kinetic and thermodynamic products, respectively. The result... |
29711336 | Synthesis of p-Phenylene Sulfide Molecular Asterisks. | "Megastars" with aromatic central cores, some of which fluoresce, were synthesized by the efficient connection of the side arms to the core by using the MacNicol reaction. Depending on the length of the side arm precursor, second-, third- (depicted), or fourth-generation molecular asterisks were obtained; a twelve-arme... |
29711322 | Encapsulation of Large, Neutral Molecules in a Self-Assembled Nanocage Incorporating Six Palladium(II) Ions. | What a large interior space in a molecule! Self-assembled cage compound 1 has a nanosized cavity (8 Å in diameter) and can encapsulate as many as four molecules of o-carborane. A bulky guest, 1,3,5-tri-tert-butylbenzene, once encapsulated by means of thermally activated slippage, cannot escape from the cavity at room t... |
29711315 | Supramolecular Aggregates of Dendritic Cyclophanes (Dendrophanes) Threaded on Molecular Rods with Steroid Termini. | Multinanometer-sized assemblies with molecular weights exceeding 14 000 are obtained by the threading of two dendritic cyclophanes (dendrophanes) onto molecular rods in which two testosterone termini are attached by rigid spacers to a central phenyl ring bearing two quaternary ammonium side chains. The formation of the... |
29711313 | Layered Dendritic Block Copolymers. | A star-shaped molecule and a layered structure are displayed by the title compound, where the layers consist of high molecular weight polymers. A core molecule that is functionalized by six hydroxyl groups acts as the initiator for the ring-opening polymerization of ε-caprolactone, leading to a six-arm star polymer. Th... |
29711302 | Sapphyrin Supramolecules through C-H⋅⋅⋅S and C-H⋅⋅⋅Se Hydrogen Bonds-First Structural Characterization of meso- Arylsapphyrins Bearing Heteroatoms. | An unprecedented coupling reaction of heteroatom-containing tripyrranes leads to the formation of core-modified sapphyrins 1 and 2, which self-assemble in the solid state to form supramolecular ladders. Weak C-H⋅⋅⋅S and C-H⋅⋅⋅Se hydrogen-bonding interactions in addition to C-H⋅⋅⋅N hydrogen bonds are responsible for the... |
29711296 | Organizational Forms of Matter: An Inorganic Super Fullerene and Keplerate Based on Molybdenum Oxide. | Plato and Kepler would have been pleased. Despite the large number of atoms present the cluster anion 1 resembles an icosahedral-type structure. This represents definitively an unprecedented event in chemistry! The structure is made up of 12 {Mo<sub>11</sub> } fragments such that the fivefold symmetry axes are retained... |
29711288 | Self-Assembling Sieves. | A modular strategy has been applied to synthesize large, porous, self-assembling capsules. The coupling of tricyclic building blocks incorporating glycoluril hydrogen-bonding units and derivatives of triethylbenzene produces monomers which readily form homo- and heterodimeric assemblies (calculated structure is shown).... |
29711281 | Closure of the Cavity in Permethylated Cyclodextrins through Glucose Inversion, Flipping, and Kinking. | Glucose-flips in a small cycloamylose: the molecular structure of permethylated γ-cyclodextrin, which crystallizes as the dihydrate, is characterized by 180° flips of two diametrically opposed glucose residues. This leads to an elliptical distortion of the molecule and closure of the molecular cavity on one side so tha... |
21644682 | Microcalorimetry of chiral surfactant-cyclodextrin interactions. | The interactions of the chiral surfactants taurodeoxycholate (TDOCA) and deoxycholate (DOCA) with a range of cyclodextrins in aqueous solution have been investigated by isothermal titration microcalorimetry. In the presence of β-cyclodextrin, the apparent critical micelle concentration (cmc) of taurodeoxycholate is inc... |
21644678 | Combinatorial synthesis of highly selective cyclohexapeptides for separation of amino Acid enantiomers by capillary electrophoresis. | Cyclic peptide libraries dissolved in the electrolyte solution can be used as chiral selectors in capillary electrophoresis. In the present investigation, the resolution obtained in capillary electrophoresis for a set of dinitrophenyl-d,l-amino acids was the parameter used to screen for the most effective selectors con... |
18967433 | Ion-pair extraction of uranyl ion from aqueous medium using crown ethers. | Ion-pair extraction behaviour of uranyl ion from aqueous solutions was studied at pH 3.0 employing crown ethers viz. benzo 15 crown 5 (B15C5), 18 crown 6 (18C6), dibenzo 18 crown 6 (DB18C6), and dibenzo 24 crown 8 (DB24C8) in chloroform as the organic phase and picric acid as the organophilic counter anion. The stoichi... |
18967423 | Protonation constant of monoaza-12-crown-4 ether and stability constants with selected metal ions in aqueous solution in the presence of an excess of sodium ion: a potentiometric and differential pulse polarographic study at fixed ligand to metal ratio and varied pH. | The ligand monoaza-12-crown-4 ether (A12C4) was studied in aqueous solution at 298 K and an ionic strength of 0.5 mol dm(-3) in the presence of an excess of sodium ion (0.5 mol dm(-3) NaNO(3)). The protonation constant of A12C4, determined by glass electrode potentiometry (GEP) in the same background electrolyte, was f... |
18967417 | Adsorbed resin phase spectrophotometric determination of vanillin or/and its derivatives. | The reactive mechanism, stability and interrelating properties, and thermodynamic constants of beta-cyclodextrin polymer (beta-CDP) including vanillin, 4-hydroxybenzaldehyde and piperonal were investigated. The effects of pH, temperature, time and solvent concentration on the inclusion reaction were determined. The opt... |
11670819 | Macrocyclic Heterodinuclear Zn(II)Pb(II) Complexes: Synthesis, Structures, and Hydrolytic Function toward Tris(p-nitrophenyl) Phosphate. | A heterodinuclear Zn(II)Pb(II) complex ZnPb(L)(ClO(4))(2).2H(2)O (1) has been obtained where (L)(2)(-) is an unsymmetric macrocycle derived from the 2:1:1 condensation of 2,6-diformyl-4-methylphenol, ethylenediamine and diethylenetriamine and has the "salen"- and "saldien"-like metal-binding sites sharing the phenolic ... |
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