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9925822
Active nuclear import and export is independent of lumenal Ca2+ stores in intact mammalian cells.
The nuclear pore complex (NPC) mediates communication between the cytoplasm and nucleus in eukaryotic cells. Active transport of large polypeptides as well as passive diffusion of smaller (approximately 10 kD) macromolecules through the NPC can be inhibited by depletion of intracellular Ca2+ stores. However, the physio...
9927437
The internal workings of a DNA polymerase clamp-loading machine.
Replicative DNA polymerases are multiprotein machines that are tethered to DNA during chain extension by sliding clamp proteins. The clamps are designed to encircle DNA completely, and they are manipulated rapidly onto DNA by the ATP-dependent activity of a clamp loader. We outline the detailed mechanism of gamma compl...
9927416
Identification of MINUS, a small polypeptide that functions as a microtubule nucleation suppressor.
In eukaryotic cells, tubulin polymerization must be regulated precisely during cell division and differentiation. To identify new mechanisms involved in cellular microtubule formation, we isolated an activity that suppresses microtubule nucleation in vitro. The activity was due to a small acidic polypeptide of 4.7 kDa ...
9927413
Supramolecular organization of the photosynthetic apparatus of Rhodobacter sphaeroides.
Native tubular membranes were purified from the purple non-sulfur bacterium Rhodobacter sphaeroides. These tubular structures contain all the membrane components of the photosynthetic apparatus, in the relative ratio of one cytochrome bc1 complex to two reaction centers, and approximately 24 bacteriochlorophyll molecul...
9927410
Leukocyte polarization in cell migration and immune interactions.
Cell migration plays a key role in a wide variety of biological phenomena. This process is particularly important for leukocyte function and the inflammatory response. Prior to migration leukocytes undergo polarization, with the formation of a lamellipodium at the leading edge and a uropod at the trailing edge. This ce...
9925630
Comparative study of biological properties and electrophoretic characteristics of lipopolysaccharide from eel-virulent and eel-A virulent Vibrio vulnificus strains.
In Vibrio vulnificus, virulence for eels is associated with serovar E strains. In this study, we investigated some biological properties of purified lipopolysaccharides (LPSs) from serovar E and non-serovar E strains. Purified LPSs retained their O-polysaccharidic side chains and did not show any differences that could...
9925594
A mutation that improves soluble recombinant hemoglobin accumulation in Escherichia coli in heme excess.
High-level expression of soluble recombinant human hemoglobin (rHb) in Escherichia coli was obtained with several hemoglobin variants. Under identical conditions, two rHbs containing the Presbyterian mutation (Asn-108-->Lys) in beta-globin accumulated to approximately twofold less soluble globin than rHbs containing th...
9922263
Effect of wzx (rfbX) mutations on A-band and B-band lipopolysaccharide biosynthesis in Pseudomonas aeruginosa O5.
The wbp cluster of Pseudomonas aeruginosa O5 encodes a number of proteins involved in biosynthesis of the heteropolymeric and Wzy-dependent B-band O antigen, including Wzy, the O-antigen polymerase, and Wzz, the regulator of O-antigen chain length. A gene (formerly wbpF), contiguous with wzy in the wbp cluster, is pred...
9920661
Protein kinase C modulation of recombinant NMDA receptor currents: roles for the C-terminal C1 exon and calcium ions.
Protein kinase C (PKC) positively modulates NMDA receptor (NMDAR) currents. In contrast to previous reports, this study determines the importance of individual exons in the mechanism underlying the potentiation process by examining the complete set of eight naturally occurring splice variants expressed in Xenopus oocyt...
9916065
Intracellular delivery of a cytolytic T-lymphocyte epitope peptide by pertussis toxin to major histocompatibility complex class I without involvement of the cytosolic class I antigen processing pathway.
A CD8(+) cytolytic T-lymphocyte (CTL) response to antigen-presenting cells generally requires intracellular delivery or synthesis of antigens in order to access the major histocompatibility complex (MHC) class I processing and presentation pathway. To test the ability of pertussis toxin (PT) to deliver peptides to the ...
9895412
In vitro release of 5-fluorouracil with cyclic core dendritic polymer.
This paper describes the first synthesis of a series of dendritic polymers with a core of 1,4,7,10-tetraazacyclododecane. This core was allowed to react with methyl acrylate through a Michael addition and was then amidated with ethylenediamine. Repeating the two steps led to controlled molecular weight increasing and b...
9895386
Inhibition of nuclear factor-kappaB activation improves the survival of rats with taurocholate pancreatitis.
<h4>Background</h4>Death in the early stages of severe acute pancreatitis is frequently the result of multiple organ dysfunction, but its mechanism is not clear.<h4>Aims</h4>To investigate the state of nuclear factor-kappaB (NF-kappaB) in macrophages of rats with lethal pancreatitis, and to assess the effectiveness of ...
9895306
Epidermal growth factor receptor activation is localized within low-buoyant density, non-caveolar membrane domains.
Increasing evidence for the organization of cell-surface proteins and lipids into different detergent-insoluble rafts led us to investigate epidermal growth factor (EGF) receptor activation in the plasma membranes of A431 carcinoma cells, using a combination of cell fractionation and immunoprecipitation techniques. Den...
9895299
Dermatopontin interacts with transforming growth factor beta and enhances its biological activity.
Dermatopontin, a recently found low-molecular-mass component of the extracellular matrix, was studied for its interaction with decorin and transforming growth factor beta (TGF-beta) and its influence on TGF-beta bioactivity. Dermatopontin reacted with decorin with an apparent Kd of 100 nM in a solid-phase assay. Dermat...
9889264
Chromatin disruption and modification.
Chromatin disruption and modification are associated with transcriptional regulation by diverse coactivators and corepressors. Here we discuss the possible structural basis and functional consequences of the observed alterations in chromatin associated with transcriptional activation and repression. Recent advances in ...
9891074
Essential role of the dynamin pleckstrin homology domain in receptor-mediated endocytosis.
Pleckstrin homology (PH) domains are found in numerous membrane-associated proteins and have been implicated in the mediation of protein-protein and protein-phospholipid interactions. Dynamin, a GTPase required for clathrin-dependent endocytosis, contains a PH domain which binds to phosphoinositides and participates in...
9882383
Formation of an RNA heterodimer upon heating of nodavirus particles.
Flock House virus is a small icosahedral insect virus of the family Nodaviridae. Its genome consists of two positive-sense RNA molecules, which are believed to be encapsidated into a single viral particle. However, evidence to support this claim is circumstantial. Here we demonstrate that exposure of nodavirus particle...
9882367
A phage single-stranded DNA (ssDNA) binding protein complements ssDNA accumulation of a geminivirus and interferes with viral movement.
Geminiviruses are plant viruses with circular single-stranded DNA (ssDNA) genomes encapsidated in double icosahedral particles. Tomato leaf curl geminivirus (ToLCV) requires coat protein (CP) for the accumulation of ssDNA in protoplasts and in plants but not for systemic infection and symptom development in plants. In ...
9882338
Evolution of the human immunodeficiency virus type 1 long terminal repeat promoter by conversion of an NF-kappaB enhancer element into a GABP binding site.
Human immunodeficiency virus type 1 (HIV-1) transcription is regulated by the viral Tat protein and cellular factors, of which the concentration and activity may depend on the cell type. Viral long terminal repeat (LTR) promoter sequences are therefore optimized to suit the specific nuclear environment of the target ho...
9882316
The surface glycoproteins of H5 influenza viruses isolated from humans, chickens, and wild aquatic birds have distinguishable properties.
In 1997, 18 confirmed cases of human influenza arising from multiple independent transmissions of H5N1 viruses from infected chickens were reported from Hong Kong. To identify possible phenotypic changes in the hemagglutinin (HA) and neuraminidase (NA) of the H5 viruses during interspecies transfer, we compared the rec...
9882309
The inhibitory activity of the AU-rich RNA element in the human papillomavirus type 1 late 3' untranslated region correlates with its affinity for the elav-like HuR protein.
A 57-nucleotide adenosine- and uridine-rich RNA instability element in the human papillomavirus type 1 late 3' untranslated region termed h1ARE has previously been shown to interact specifically with three nuclear proteins that failed to bind to an inactive mutant RNA. Two of those were identified as the heterogeneous ...
10903103
Beta-cyclodextrin(beta-CD) influence on the biotoxicities of substituted benzene compounds and pesticide intermediates.
The acute toxicities of 19 substituted benzene compounds and intermediates of pesticides to Photobacterium phosphoreum in beta-CD aqueous solution (5 g/L) were studied and compared with those in water through luminescent bacteria toxicity test, and 15min-EC50 values were obtained. The presence of beta-CD significantly ...
10563953
Enantiomeric purity and odor characteristics of 2- and 3-acetoxy-1, 8-cineoles in the rhizomes of Alpinia galanga willd.
(S)-(+)-O-methylmandelate esters of trans- and cis-1,3, 3-trimethyl-2-oxabicyclo[2.2.2]octan-5- and 6-ols (2- and 3-hydroxy-1,8-cineoles) were prepared, and eight diastereomers were separated. The absolute configuration of the asymmetric carbons of the cineole moiety of each diastereomer was determined by (1)H NMR data...
10563926
Cyclodextrins as activator and inhibitor of latent banana pulp polyphenol oxidase.
The effect of cyclodextrins (CDs) on o-diphenol oxidation catalyzed by banana polyphenol oxidase (PPO) was studied. The oxidation of dopamine, the natural substrate of banana, in the presence of cyclodextrins was unaffected, because this hydrophilic phenol does not form inclusion complexes with CDs. However, when a hyd...
10563920
Quantification of racemization of amino acids in alkaline-treated duck eggs by micellar capillary electrophoresis.
Duck eggs were pickled in 4.2% NaOH/5% NaCl solution for 20 days to prepare the traditional Chinese Pidan. The extent of racemization of compositional amino acid in egg albumen and yolk over the alkaline pickling period was investigated with micellar capillary electrophoresis (MCE) using beta-cyclodextrin as chiral sel...
10499106
Complete isomer-specific 1H and 13C NMR assignments of the heme resonances of rat liver outer mitochondrial membrane cytochrome b5.
Singly and doubly labeled delta-aminolevulinic acid derivatives were used to prepare rat liver outer mitochondrial membrane (OM) cytochrome b5 containing a 13C-labeled heme active site. A variety of NMR experiments, including HMBC and INADEQUATE in conjunction with the more commonly used HMQC, NOESY, and COSY, were con...
10499099
Solution structure of reduced horse heart cytochrome c.
In the frame of a broad study on the structural differences between the two redox forms of cytochromes to be related to the electron transfer process, the NMR solution structure of horse heart cytochrome c in the reduced form has been determined. The structural data obtained in the present work are compared to those al...
10229713
Environmental occurrence, analysis, and toxicology of toxaphene compounds.
Toxaphene production, in quantities similar to those of polychlorinated biphenyls, has resulted in high toxaphene levels in fish from the Great Lakes and in Arctic marine mammals (up to 10 and 16 microg g-1 lipid). Because of the large variabiliity in total toxaphene data, few reliable conclusions can be drawn about tr...
10229711
Comparison of short-term estrogenicity tests for identification of hormone-disrupting chemicals.
The aim of this study was to compare results obtained by eight different short-term assays of estrogenlike actions of chemicals conducted in 10 different laboratories in five countries. Twenty chemicals were selected to represent direct-acting estrogens, compounds with estrogenic metabolites, estrogenic antagonists, an...
10420972
Phage display in proteolysis and signal transduction.
The power of the phage display technology relies on the coupling of the functional display of combinatorial peptide or protein libraries with the ability of each member in the library to self-replicate and, at the same time, to encode the primary structure of the displayed polypeptide in its genome. Phage display syste...
10337398
The thermal decomposition of dimethoate.
The thermal decomposition of dimethoate, an organophosphorus pesticide, has been studied with the aim at assessing the reaction kinetics, the energy released during the process and the decomposition products. Dimethoate shows a marked tendency to undergo thermal decomposition at temperature higher than 369 K. A moderat...
9971739
The intermediate filament protein peripherin is the specific interaction partner of mouse BPAG1-n (dystonin) in neurons.
The dystonia musculorum (dt) mouse suffers from severe degeneration of primary sensory neurons. The mutated gene product is named dystonin and is identical to the neuronal isoform of bullous pemphigoid antigen 1 (BPAG1-n). BPAG1-n contains an actin-binding domain at its NH2 terminus and a putative intermediate filament...
10231030
Characterization of a single-copy Arabidopsis gene encoding a protein showing limited similarity to the N-terminus of the mammalian clathrin-assembly protein AP180.
The Arabidopsis 194 gene encoding a protein containing sequence similarity to an N-terminal region of the clathrin-assembly protein AP180 has been identified in a 4.9-kb region of genomic DNA upstream of the gene encoding the high mobility group protein HMG-I/Y. The gene consists of 12 exons and 11 introns, identified ...
10218368
Mechanisms of ventilation-induced lung injury: physiological rationale to prevent it.
It is being increasingly realized that modes of mechanical ventilation that result in end-inspiratory alveolar overstretching and/or repeated alveolar collapse and re-expansion disturb the normal fluid balance across the alveolocapillary membrane. The effects of this include disturbance of the integrity of the endothel...
10218831
Conformational studies on the specific cleavage site of Type I collagen (alpha-1) fragment (157-192) by cathepsins K and L by proton NMR spectroscopy.
Cathepsins K and L are cysteine proteinases which are considered to play an important role in bone resorption. Type I collagen is the most abundant component of the extracellular matrix of bone and regarded as an endogenous substrate for the cysteine proteinases in osteoclastic bone resorption. We have synthesized a fr...
10218825
Models for superoxide dismutases: characterization of mononuclear Cu(II), Fe(III), and Mn(II) complexes with 4',5'-bis(salicylideneimino)benzo-15-crown-5.
Mononuclear Cu(II), Fe(III), and Mn(II) complexes with 4',5'-bis (salicylideneimino)benzo-15-crown-5, (SALH2), were characterized by elemental analysis, IR and UV-Vis spectroscopy and tested spectrometrically as catalysts for superoxide disproportionation by utilizing xanthine-xanthine oxidase (XXO) assays. The results...
10216958
The fibrillins.
Fibrillins 1 and 2 are the main constituents of the extracellular microfibrils responsible for the biomechanical properties of most tissues and organs. They are cysteine-rich glycoproteins predominantly made of multiple repeats homologous to the calcium-binding epidermal growth factor module, and are translated as prec...
10205678
Sedimentation analysis of muscle glycogen phosphorylase b entrapped in hydrated reversed micelles of aerosol OT in octane.
The oligomeric state and formation of supramolecular structures of glycogen phosphorylase b from rabbit skeletal muscles have been studied in the system of hydrated reversed micelles of aerosol OT (AOT) in octane. Sedimentation studies show that the oligomeric state of the enzyme is controlled by the degree of hydratio...
10205642
alpha-Chymotrypsin-catalyzed degradation of desmopressin (dDAVP): influence of pH, concentration and various cyclodextrins.
Desmopressin [1-(mercaptopropanoic acid)-8-D-arginine vasopressin; dDAVP] is a vasopressin analogue with a selective antidiuretic effect. The oral bioavailability of desmopressin is limited due both to its high hydrophilicity leading to a low intestinal permeability and to low enzymatic stability. The degradation of de...
10195285
A three-dimensional construction of the active site (region 507-749) of human neutral endopeptidase (EC.3.4.24.11).
A three-dimensional model of the 507-749 region of neutral endopeptidase-24.11 (NEP; E.C.3.4.24.11) was constructed integrating the results of secondary structure predictions and sequence homologies with the bacterial endopeptidase thermolysin. Additional data were extracted from the structure of two other metalloprote...
10193541
Effects of early enteral nutrition on intestinal permeability and the development of multiple organ failure after multiple injury.
<h4>Objective</h4>To determine how immediate enteral nutrition (EN) affects gut permeability and the development of multiple organ failure (MOF) in multiply injured patients.<h4>Design</h4>Prospective, randomised clinical trial.<h4>Setting</h4>20-bed surgical intensive care unit (ICU), university hospital.<h4>Patients<...
10190651
Platelet alpha2-adrenoceptor alterations in patients with essential hypertension.
<h4>Aims</h4>The purpose of this study was to determine whether human platelet alpha2-adrenoceptors were altered in essential hypertension. A systematic analysis was carried out on 165 normotensives and 124 untreated primary hypertensives.<h4>Methods</h4>The study was performed at different levels: i) density and affin...
10190576
Deuterium isotope effects on noncovalent interactions between molecules.
The topic of deuterium isotope effects is usually concerned with the effects on chemical reactions that are caused by the substitution of deuterium atoms for protium, or hydrogen, atoms in a molecule. These effects include changes in the rate of cleavage of covalent bonds to deuterium, or to an atom located adjacent to...
10188582
Light perception in higher plants.
Photosynthetic plants depend on sunlight as their energy source. Thus, they need to detect the intensity, quality and direction of this critical environmental factor and to respond properly by optimizing their growth and development. Perception of light is accomplished by several photoreceptors including phytochromes, ...
10101837
Immobilization of histidine-tagged proteins on gold surfaces using chelator thioalkanes.
The reversible, oriented immobilization of proteins on solid surfaces is a prerequisite for the investigation of molecular interactions and the controlled formation of supramolecular assemblies. This paper describes a generally applicable method using a synthetic chelator thioalkane that can be self-assembled on gold s...
10098923
Cell adhesion and histocompatibility in sponges.
Sponges are the lowest extant metazoan phylum and for about a century they have been used as a model system to study cell adhesion. There are three classes of molecules in the extracellular matrix of vertebrates: collagens, proteoglycans, and adhesive glycoproteins, all of them have been identified in sponges. Species-...
10092881
Molecular cloning, cell localization and binding affinity to DNA replication proteins of the p36/LACK protective antigen from Leishmania infantum.
The p36/LACK antigen from Leishmania, an analogue of the receptor for activated protein kinase C (PKC), induces high levels of protection against parasite infection in the BALB/c mouse model. This protection is more than twice as high as that elicited by major parasite antigens such as soluble Leishmania antigen or the...
10094484
Chemical modification of lysine side chains of cyclodextrin glycosyltransferase from Thermoanaerobacter causes a shift from cyclodextrin glycosyltransferase to alpha-amylase specificity.
Cyclodextrin glycosyltransferases and alpha-amylases are two groups of enzymes with related secondary structures. However, cyclodextrin glycosyltransferases display transferase activities not present in alpha-amylases, probably derived from the existence of two more domains and different amino acid sequences. The hydro...
10092139
Detection of Epstein-Barr virus EBER sequence in post-transplant lymphoma patients with DNA dendrimers.
The EBER RNAs are the most numerous viral transcripts in latently infected lymphocytes in healthy individuals and also in the tumor cells of Epstein Barr virus (EBV)-associated malignancies. A rise in EBV load in peripheral blood has been associated with the onset of post-transplant lymphoproliferative disease (PTLD) i...
10085788
Lipid grafts of egg-box complex: a new supramolecular biovector for 5-fluorouracil delivery.
An attempt was made to improve the pharmacokinetic behaviour of 5-fluorouracil (5-FU) by incorporating it into lipoprotein imitating synthetic carrier 'supramolecular biovector (SMBV)' which is an important prerequisite for achieving its better therapeutic performance against cancer. The polysaccharide core of SMBVs wa...
25138521
Molecular Recognition within a Self-Assembled Cylindrical Host.
A change in geometry is necessary on entry into the capsule: a supramolecular associate approximately 1.8 nm long (see schematic representation), which consists of two halves stabilized by hydrogen bonds, influences the intra- and intermolecular interactions of the guest molecules encapsulated. Thus tertiary amides and...
25138511
A spreader-bar approach to molecular architecture: formation of stable artificial chemoreceptors.
The destructive influence of lateral diffusion on nanostructured monolayers can be prevented by using the spreader-bar technique. This approach allows the formation of stable artificial receptors for barbituric acid by lateral structuring of a dodecanethiol monolayer with molecular spreader-bars from thiobarbituric aci...
25138491
Crystalline bacterial cell surface layers (s layers): from supramolecular cell structure to biomimetics and nanotechnology.
An astonishingly broad application potential in biotechnology, biomimetics, and nanotechnology is revealed by studies on the structure, chemistry, biosynthesis, genetics, self-assembly, and function of supramolecular surface layers (S layers). These are monomolecular, crystalline assemblies of protein or glycoprotein s...
25138490
Structural classification and general principles for the design of spherical molecular hosts.
Cryptands, carcerands, polyoxometalates, and molecular capsules are cagelike hosts that complex guests through encapsulation. Following the discovery of a nanometer scale supramolecular shell-like spheroid, these and other shell-like hosts were structurally classified. Their frameworks may be catalogued according to pr...
23105203
Biochemical diagnosis of liver disease.
It is important that clinicians and laboratorians, including clinical chemists and pathologists, recognize and understand the clinical significance of abnormal liver function tests. The liver regulates many important metabolic functions. Hepatic injury is associated with distortion of these metabolic functions. Hepatic...
21662946
Preparation and characterization of dendrimer-gold colloid nanocomposites.
Au colloids in the 2-3-nm size regime were prepared by in situ reduction of HAuCl(4) in the presence of poly(amidoamine) dendrimers. The dendrimers encapsulate the colloids, imparting stability to the aqueous colloidal solutions. The nanocomposite materials can be isolated by precipitation. The dendrimer generation use...
21662936
Calixarene monolayers as quartz crystal microbalance sensing elements in aqueous solution.
We have examined p-tert-butylcalix[4]arenetetrathiolate (BCAT) monolayers for their potential use as molecular recognition elements for in situ aqueous chemical sensors. Spectroscopic and wetting studies of BCAT monolayers on Au{111} reveal that the calixarene molecules exist in monolayers, preferentially oriented with...
21394239
Selective extraction of strontium with supercritical fluid carbon dioxide.
Strontium (Sr(2+)) can be selectively extracted from aqueous solutions into supercritical fluid CO(2) at 60 °C and 100 atm with dicyclohexano-18-crown-6 (DC18C6) using CF(3)(CF(2))(6)CO(2) (-) (PFOA(-)) or CF(3)(CF(2))(6)CF(2)SO(3) (-) (PFOSA(-)) as a counter anion; at a mole ratio of Sr(2+) : DC18C6 : PFOA(-) = 1:10:5...
21080259
Improved 1HN-detected triple resonance TROSY-based experiments.
A pulse scheme resulting in improved sensitivity in TROSY-based 1HN-detected triple resonance experiments is presented. The approach minimizes relaxation losses which occur during the transfer of transverse magnetization from 15N to 1HN immediately prior to detection. The utility of the method is demonstrated on a comp...
18967439
Room temperature phosphorescence of 1-naphtalenacetamide included in beta-cyclodextrin in presence of 1,3-dibromopropane.
The spectral characteristics of the inclusion of 1-naphthalenacetamide in beta-cyclodextrin have been studied by luminescence methods. The addition of bromoalcohols or bromoalkanes produces a decrease of the fluorescence of the inclusion complex, giving rise to a new band corresponding to phosphorescence emission. The ...
18475911
Synthesis, Characterisation and Anti-Fungal Activities of Some New Copper(II) Complexes of Octamethyl Tetraaza-Cyclotetradecadiene.
The ligand Me(8)[14]diene, L, in its free state as well as in the dihydroperchlorate form, L.2HClO(4), coordinates copper(ll) in different salts to yield a series of [CuLX(x)] X(y)(H(2)O)(z) complexes where X = NO(3), ClO(4), NCS, Cl and Br; x and y may have values of 0 or 2 and z = 0, 1 or 2. The complex, [CuL(ClO(4))...
18472904
Ferrocene-derived pyrazinoyl and nicotinoyl schiff-bases: their synthesis, characterization and biological properties.
A novel class of acetylferrocene-derived Schiff-bases such as 2-pyrazinoyl-1-(2-ferroceneylmethylene)- hydrazide (HL(1)) and 2-nicotinoyl-1-(2-ferrocenylmethylene)hydrazide (HL(2)) have been synthesized and characterized by their IR, (1)H NMR, (13)C NMR and microanalytical date. The biological effect induced due to the...
18475888
Functionalized Derivatives of Benzo-Crown Ethers. Part 4. Antifungal Macrocyclic Supramolecular Complexes of Transition Metal Ions Acting as Lanosterol-14-alpha-Demethylase Ihibitors.
Poly- and mononuclear metal complexes of 2,3,11,12-bis[4-(10-aminodecylcarbonyl)]benzo-18- crown-6 (L) and Cu(II); Ni(II); Co(II) and Cr(III) have been synthesized and characterized by standard physico-chemical procedures. In the newly prepared complexes the crown moiety oxygen atoms of the macrocyclic host did not gen...
16232640
Effectiveness of polyamidoamine dendrimers modified with tripeptide growth factor, glycyl-L-histidyl-L-lysine, for enhancement of function of hepatoma cells.
Cationic polyamidoamine dendrimers are known to be highly branched cascade polymers. Tripeptide growth factor, glycyl-L-histidyl-L-lysine (GHK), was employed as a ligand for activation or attachment of cells from a rat hepatoma cell line, H4-H-E-C3, and immobilized at the terminus of the dendrimer (GHK-dendrimer) to de...
16232518
The concept of the alpha-amylase family: structural similarity and common catalytic mechanism.
This review reconsiders the concept of the alpha-amylase family in the light of the recent wealth of information on the structures, the catalytic mechanisms, and the classification of amylases. We proposed a general concept for an enzyme family, the alpha-amylase family including most of the amylases and related enzyme...
10561711
Enantiomeric composition of the polycyclic musks HHCB and AHTN in different aquatic species
Synthetic polycyclic musk fragrances are mainly represented by the compounds HHCB (Galaxolide(TM)) and AHTN (Tonalide(TM)). Because of their volume of use and their bioaccumulation potential, there is concern with respect to their environmental safety. HHCB and AHTN are chiral compounds, and gas chromatography using mo...
10561706
Enantiomer separation of 7-des-methyl-ormeloxifene using sulfated beta-cyclodextrin in countercurrent chromatography
The enantiomers of 7-des-methyl-ormeloxifene were separated by countercurrent chromatography (CCC) using sulfated beta-cyclodextrin as chiral selector, representing the first reported successful application of a cyclodextrin derivative in CCC-based resolutions. The choice of chiral selector relies on extreme separation...
9933524
In situ detoxification of the fermentation medium during gamma-decalactone production with the yeast sporidiobolus salmonicolor
gamma-Decalactone (gamma-C10) is known to be highly toxic for the microorganims used for its production. In this work, three techniques were studied in order to overcome this toxicity during a bioconversion process using ricinoleic acid as precursor of the lactone: in situ trapping in oily phases, in porous hydrophobic...
9915696
Conversion of supramolecular clusters to macromolecular objects
In a reaction proceeding within a nanoscopic volume, supramolecular clusters were transformed to polymer objects while retaining their shape and size. Spatial isolation of the cross-linkable blocks of oligobutadiene that were involved in this stitching reaction was achieved by self-assembly of the molecules that made u...
10523765
Observation of triply charged metal ion clusters by electrospray and laser spray
Studies of the gas phase ion chemistry of triply charged metal ions, M(3+) = Sc(3+), Y(3+), La(3+), Ce(3+), and Yb(3+), were made by electrospray and laser spray. Triply charged ion ligand complexes, M(3+)(ligand)(n) were produced in the gas phase by electrospray and laser spray for the following ligands; glucose; sucr...
10423280
Substituent effects in the selective reductive opening of epoxides with borohydrides in the presence of beta-cyclodextrin
The opening of ortho-substituted phenyl oxiranes by borohydrides is described both in aqueous and solid phases. Some remarkable differences in the regioselectivity and inversion of enantioselectivity of oxirane ring-opening are reported. The results obtained are compared with previous studies and have allowed some fact...
10076012
Interaction of photosynthetic pigments with various organic solvents. Magnetic circular dichroism approach and application to chlorosomes
Magnetic circular dichroism (MCD) and absorption spectra have been measured on three intact photosynthetic pigments with the chlorin ring as macrocycle: chlorophyll a, bacteriochlorophyll c and d, in various hydrophilic organic solvents. The MCD intensity of a Qy(0-0) transition for the Mg chlorin derivative was sensit...
9888850
Self-assembly of ordered microporous materials from rod-coil block copolymers
Rod-coil diblock copolymers in a selective solvent for the coil-like polymer self-organize into hollow spherical micelles having diameters of a few micrometers. Long-range, close-packed self-ordering of the micelles produced highly iridescent periodic microporous materials. Solution-cast micellar films consisted of mul...
9878148
A Combined Surface-Enhanced Raman-X-Ray Photoelectron Spectroscopic Study of 2-mercaptobenzothiazole Monolayers on Polycrystalline Au and Ag Films.
The monolayers of 2-mercaptobenzothiazole (MBT) on polycrystalline Au and Ag films have been studied by surface-enhanced Raman (SERS) and X-ray photoelectron (XPS) spectroscopies. Whereas MBT adsorbs with its molecular plane flat on Ag, its plane is perpendicular on Au. This difference in adsorbate geometry is manifest...
9872783
Production of wax esters during aerobic growth of marine bacteria on isoprenoid compounds
This paper describes the production of isoprenoid wax esters during the aerobic degradation of 6,10,14-trimethylpentadecan-2-one and phytol by four bacteria (Acinetobacter sp. strain PHY9, Pseudomonas nautica [IP85/617], Marinobacter sp. strain CAB [DSMZ 11874], and Marinobacter hydrocarbonoclasticus [ATCC 49840]) isol...
9872741
Chain length recognition: core-shell supramolecular assembly from oppositely charged block copolymers
Molecular recognition based on length was found to occur between oppositely charged pairs of flexible and randomly coiled block copolymers in an aqueous milieu. Matched pairs with the same block lengths of polyanions and polycations exclusively formed even in mixtures with different block lengths. These assemblies of t...
9826409
Selective Cerebral Perfusion Via Innominate Artery in Aortic Arch Replacement Without Deep Hypothermic Circulatory Arrest.
To attain satisfactory results in aortic arch surgery a reliable method of cerebral protection, avoidance of emboli, and control of hemorrhage is mandatory. Deep hypothermic circulatory arrest is the most common technique at present but gives only a limited period of protection, whereas a complicated aortic arch operat...
10077267
Metachromatic activity of beta-cyclodextrin sulfates as heparin mimics.
Heparin is a versatile biologically active substance which has been reported to have an inhibitory effect on angiogenesis if administered together with hydrocortisone. Since very little is known about the mechanism of this activity, beta-cyclodextrin sulfates were prepared to mimic heparin. The sulfate groups were intr...
10077239
Effect of the cannabinoid receptor agonist WIN55212-2 on sympathetic cardiovascular regulation.
1. The aim of the present study was to analyse the cardiovascular actions of the synthetic CB1/CB2 cannabinoid receptor agonist WIN55212-2, and specifically to determine its sites of action on sympathetic cardiovascular regulation. 2. Pithed rabbits in which the sympathetic outflow was continuously stimulated electrica...
10070764
Rapid drug metabolite profiling using fast liquid chromatography, automated multiple-stage mass spectrometry and receptor-binding.
Rapid drug metabolite profiling can be achieved using fast chromatographic separation and fast mass spectrometric scanning without compromising the separation efficiency. Fast chromatographic separations of drug and its metabolites can be achieved by eluting from a short narrow-bore guard cartridge column (20 x 2 mm I....
10065153
Covalent and noncovalent modifiers of the p53 protein.
Despite the massive attention it has received, there is still much to learn about the p53 tumour suppressor protein. Given that it plays complex and multiple roles in cells, it is not surprising that p53 is subjected to an intricate array of regulatory processes. p53 receives signals from cells in multiple ways, leadin...
10065979
Chiral separation of lobeline analogs using high performance capillary electrophoresis and derivatized cyclodextrins as chiral additives.
High performance capillary electrophoresis (HPCE) methods are described that will separate the enantiomers of various lobeline analogs synthesized in these laboratories. "Cyclodextrin array analysis" was used for preliminary screening and electrophoresis conditions were optimized for each investigated analog. The lobel...
10065978
Simultaneous separation and enantioresolution of racemic local anesthetic drugs by capillary zone electrophoresis with Tween 20 and methyl-beta-cyclodextrin as selectors, employing a double plug technique.
A new approach for simultaneous chiral and achiral separations by capillary zone electrophoresis is described. Two adjacent selector plugs, consisting of Tween 20 as an achiral and methyl-beta-cyclodextrin (CD) as a chiral selector, are employed and four related local anesthetics are used as model compounds. The princi...
10065977
Chiral resolution of atropine, homatropine and eight synthetic tropinyl and piperidinyl esters by capillary zone electrophoresis with cyclodextrin additives.
Chiral resolution of atropine, homatropine and eight synthetic tropinyl and piperidinyl esters were studied by capillary zone electrophoresis with cyclodextrin additives. Atropine and eight synthetic derivatives were successfully resolved by heptakis-(2,3,6-tri-O-methyl)-beta-cyclodextrin (TM-beta-CD) at concentrations...
10065976
Enantiomer separation of drugs by capillary electrophoresis using mixtures of beta-cyclodextrin sulfate and neutral cyclodextrins.
Direct separation of enantiomers of drugs was investigated by capillary electrophoresis employing mixtures of charged cyclodextrin derivatives (CDs) and electrically neutral CDs (i.e., dual CD system). Among various charged CDs employed, it was found that beta-CD sulfate showed relatively wide enantioselectivity for a ...
10065975
Determination of association constants between enantiomers of orciprenaline and methyl-beta-cyclodextrin as chiral selector by capillary zone electrophoresis using a partial filling technique.
The principles for the determination of conditional association constants of enantiomers by capillary zone electrophoresis employing a partial filling technique (PFT) using methyl-beta-cyclodextrin as chiral selector is presented. Orciprenaline was used as a model compound. Partial filling is a separation technique, wh...
10065974
Estimation of the pH-independent binding constants of alanylphenylalanine and leucylphenylalanine stereoisomers with beta-cyclodextrin in the presence of urea.
The separation of stereoisomers, particularly enantiomers, is important when their physiological activity differs. We have resolved the four stereoisomers each of alanylphenylalanine (Ala-Phe) and of leucylphenylalanine (Leu-Phe) by capillary electrophoresis using beta-cyclodextrin as a buffer additive and urea to enha...
10028428
Solubility, 1H-NMR, and molecular mechanics of mebendazole with different cyclodextrins.
The solubility behavior and binding constants (Kass) of mebendazole with alpha-, beta-, gamma-, and hydroxypropyl-beta-cyclodextrins (HP-beta-CD) have been investigated in simulated intestinal juice by the Higuchi and Connors method. AL diagrams have been obtained. The equilibrium has also been studied in simulated gas...
10028427
Study of the binding in an aqueous medium of inclusion complexes of several cyclodextrins involving fenoprofen calcium.
Interactions among fenoprofen calcium and alpha-, beta-, gamma- and hydroxypropyl-beta-cyclodextrins (HP-beta-CD) were evaluated in aqueous solution by UV/vis and fluorescence direct spectroscopies and monodimensional (1D) 1H-NMR. Different UV/vis and fluorescence emission spectra were obtained to study the apparent bi...
10027208
Dissolution of ibuprofen enantiomers from coprecipitates and suspensions containing chiral excipients.
The purpose of this research was to evaluate the stereospecific interaction of ibuprofen with chiral excipients such as hydroxypropyl-beta-cyclodextrin (HPCD), tartaric acid, sucrose, hydroxypropylmethylcellulose (HPMC), methylcellulose (MC), and a nonchiral excipient, citric acid. Coprecipitates of ibuprofen were prep...
10021365
How a fungus escapes the water to grow into the air.
Fungi are well known to the casual observer for producing water-repelling aerial moulds and elaborate fruiting bodies such as mushrooms and polypores. Filamentous fungi colonize moist substrates (such as wood) and have to breach the water-air interface to grow into the air. Animals and plants breach this interface by m...
10021940
Macrocyclic hexapeptide analogues of the thrombin receptor (PAR-1) activation motif SFLLRN.
The thrombin receptor (PAR-1) is activated by alpha-thrombin to stimulate various cell types, including platelets, through the tethered-ligand sequence SFLLRN. Macrocyclic peptide analogues of SFLLRN were synthesized and evaluated in vitro. In general, the compounds were much less potent in inducing platelet aggregatio...
9989664
Enhanced absorption of cyclosporin A by complexation with dimethyl-beta-cyclodextrin in bile duct-cannulated and -noncannulated rats.
The enhancing effects of dimethyl-beta-cyclodextrin (DM-beta-CyD) on the absorption of cyclosporin A (CsA) after oral administration to rats under bile duct-cannulated and -noncannulated conditions were investigated. The dissolution rate of CsA was markedly augmented by complexation with DM-beta-CyD. In a closed loop i...
9987506
[Late phase II clinical study of RP56976 (docetaxel) in patients with advanced/recurrent head and neck cancer].
A late phase II clinical study of RP56976 (docetaxel), a new anticancer agent for advanced/recurrent head and neck cancer, was conducted in 29 institutions all over Japan as a multi-institutional cooperative study. Docetaxel was administered by 1 to 2-hour intravenous infusion at a dose of 60 mg/m2 every 3 to 4 weeks. ...
9987157
Sulfolipo-cyclodextrin in squalane-in-water as a novel and safe vaccine adjuvant.
Previously, we described synergistic adjuvanticity of combinations of synthetic sulfolipo(SL)-derivatives of polysaccharide (SL-polysaccharides) and squalane-in-water emulsions (squalane/W). In this paper, effects of type of polysaccharide and nature of oil on adjuvanticity, reactogenicity and stability are described. ...
9917384
The TATA-binding protein from Saccharomyces cerevisiae oligomerizes in solution at micromolar concentrations to form tetramers and octamers.
Equilibrium analytical ultracentrifugation has been used to determine the stoichiometry and energetics of the self-assembly of the TATA-binding protein of Saccharomyces cerevisiae at 30 degreesC, in buffers ranging in salt concentration from 60 mM KCl to 1 M KCl. The data are consistent with a sequential association mo...
9972501
Effect of protective colloids on the induction of polymorphic changes in indomethacin agglomerates after solvent evaporation from o/w emulsions.
Indomethacin (IMC) agglomerates were prepared by the solvent evaporation process from o/w emulsions containing different protective colloids in the external aqueous solution. The types of protective colloids inducing the polymorphic transformation of IMC in the agglomerates without wall material were investigated. The ...
9933571
Localization of the gene coding for ROCK II/Rho kinase on human chromosome 2p24.
Serine/threonine kinase ROCK II/Rho kinase, which is an isozyme of ROCK I, is one of the targets for the small GTPase Rho. ROCK II regulates the formation of actin stress fibers and focal adhesions, cytokinesis, smooth muscle contraction, and the activation of c-fos serum response element. To elucidate the role of ROCK...
9950295
A novel formulation of VIP in sterically stabilized micelles amplifies vasodilation in vivo.
<h4>Purpose</h4>To determine whether human vasoactive intestinal peptide (VIP)-poly(ethylene glycol) (PEG)-grafted distearoyl-phosphatidylethanolamine (DSPE) micelles elicit potent and stable vasodilation in vivo.<h4>Methods</h4>PEG-DSPE micelles were prepared by co-precipitation. VIP was loaded into micelles by incuba...
9950290
Dependency of gastrointestinal toxicity on release rate of tiaprofenic acid: a novel pharmacokinetic-pharmacodynamic model.
<h4>Purpose</h4>To test the hypothesis that modification of release pattern of nonsteroidal anti-inflammatory drugs (NSAIDs) formulations shifts gastrointestinal (GI) toxicity of the drugs from the upper GI region to the distal intestine.<h4>Methods</h4>We assessed tiaprofenic acid (TA)-induced upper and lower increase...