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10585964 | Alkaliphiles: some applications of their products for biotechnology. | The term "alkaliphile" is used for microorganisms that grow optimally or very well at pH values above 9 but cannot grow or grow only slowly at the near-neutral pH value of 6.5. Alkaliphiles include prokaryotes, eukaryotes, and archaea. Many different taxa are represented among the alkaliphiles, and some of these have b... |
10587346 | A role for lipid rafts in B cell antigen receptor signaling and antigen targeting. | The B cell antigen receptor (BCR) serves both to initiate signal transduction cascades and to target antigen for processing and presentation by MHC class II molecules. How these two BCR functions are coordinated is not known. Recently, sphingolipid- and cholesterol-rich plasma membrane lipid microdomains, termed lipid ... |
10585481 | In vitro reconstitution of the bacteriophage T4 clamp loader complex (gp44/62). | The clamp loader complex (CLC) of bacteriophage T4 is essential for viability and has analogs in both prokaryotes and eukaryotes. The gp44 and gp62 subunits of the T4 CLC, in a 4:1 ratio, tightly associate such that the two proteins co-purify. Using transformed Escherichia coli, we were able to demonstrate for the firs... |
10585403 | gamma-cyclodextrins greatly enhance translocation of hydrophobic fluorescent phospholipids from vesicles to cells in culture. Importance of molecular hydrophobicity in phospholipid trafficking studies. | Short-chain, fluorescent derivatives are commonly used to investigate intracellular phospholipid trafficking. However, their use can yield misleading results because they, unlike the native species, can rapidly distribute between organelles due to their low hydrophobicity. On the other hand, hydrophobic derivatives are... |
10585900 | The sources, fate, and toxicity of chemical warfare agent degradation products. | We include in this review an assessment of the formation, environmental fate, and mammalian and ecotoxicity of CW agent degradation products relevant to environmental and occupational health. These parent CW agents include several vesicants: sulfur mustards [undistilled sulfur mustard (H), sulfur mustard (HD), and an H... |
10585960 | A direct comparison of selectin-mediated transient, adhesive events using high temporal resolution. | Leukocyte capture and rolling on the vascular endothelium is mediated principally by the selectin family of cell adhesion receptors. In a parallel plate flow chamber, neutrophil rolling on purified selectins or a selectin-ligand substrate was resolved by high speed videomicroscopy as a series of ratchet-like steps with... |
10585956 | High-resolution nonlinear optical imaging of live cells by second harmonic generation. | By adapting a laser scanning microscope with a titanium sapphire femtosecond pulsed laser and transmission optics, we are able to produce live cell images based on the nonlinear optical phenomenon of second harmonic generation (SHG). Second harmonic imaging (SHIM) is an ideal method for probing membranes of living cell... |
10585955 | Spectroscopic properties of the CP43 core antenna protein of photosystem II. | CP43 is a chlorophyll-protein complex that funnels excitation energy from the main light-harvesting system of photosystem II to the photochemical reaction center. We purified CP43 from spinach photosystem II membranes in the presence of the nonionic detergent n-dodecyl-beta,D-maltoside and recorded its spectroscopic pr... |
10585915 | Annealing accounts for the length of actin filaments formed by spontaneous polymerization. | We measured the lengths of actin filaments formed by spontaneous polymerization of highly purified actin monomers by fluorescence microscopy after labeling with rhodamine-phalloidin. The length distributions are exponential with a mean of approximately 7 microm (2600 subunits). This length is independent of the initial... |
10581425 | Influence of the preparation method on the physicochemical properties of binary systems of econazole with cyclodextrins. | Equimolar combinations of econazole, a very poorly water soluble antifungal agent, with beta-cyclodextrin and statistically substituted methyl-beta-cyclodextrin were investigated for both solid state characterization (differential scanning calorimetry, hot-stage microscopy, infrared spectroscopy, scanning electron micr... |
10583411 | Self-assembly and catalytic activity of the pyruvate dehydrogenase multienzyme complex from Bacillus stearothermophilus. | The pyruvate dehydrogenase multienzyme complex from Bacillus stearothermophilus was reconstituted in vitro from recombinant proteins derived from genes over-expressed in Escherichia coli. Titrations of the icosahedral (60-mer) dihydrolipoyl acetyltransferase (E2) core component with the pyruvate decarboxylase (E1, alph... |
10581249 | Interaction of agrin with laminin requires a coiled-coil conformation of the agrin-binding site within the laminin gamma1 chain. | Coiled-coil domains are found in a wide variety of proteins, where they typically specify subunit oligomerization. Recently, we have demonstrated that agrin, a multidomain heparan sulfate proteoglycan with a crucial role in the development of the nerve-muscle synapse, binds to the three-stranded coiled-coil domain of l... |
10581235 | The structure of a chromosomal high mobility group protein-DNA complex reveals sequence-neutral mechanisms important for non-sequence-specific DNA recognition. | The high mobility group (HMG) chromosomal proteins, which are common to all eukaryotes, bind DNA in a non-sequence-specific fashion to promote chromatin function and gene regulation. They interact directly with nucleosomes and are believed to be modulators of chromatin structure. They are also important in V(D)J recomb... |
10584007 | Biodegradation of free phytol by bacterial communities isolated from marine sediments under aerobic and denitrifying conditions. | Biodegradation of (E)-phytol [3,7,11, 15-tetramethylhexadec-2(E)-en-1-ol] by two bacterial communities isolated from recent marine sediments under aerobic and denitrifying conditions was studied at 20 degrees C. This isoprenoid alcohol is metabolized efficiently by these two bacterial communities via 6,10, 14-trimethyl... |
10584004 | Isolation and characterization of the epoxide hydrolase-encoding gene from Xanthophyllomyces dendrorhous. | The epoxide hydrolase (EH)-encoding gene (EPH1) from the basidiomycetous yeast Xanthophyllomyces dendrorhous was isolated. The genomic sequence has a 1,236-bp open reading frame which is interrupted by eight introns that encode a 411-amino-acid polypeptide with a calculated molecular mass of 46.2 kDa. The amino acid se... |
10583971 | cis-chlorobenzene dihydrodiol dehydrogenase (TcbB) from Pseudomonas sp. strain P51, expressed in Escherichia coli DH5alpha(pTCB149), catalyzes enantioselective dehydrogenase reactions. | cis-Chlorobenzene dihydrodiol dehydrogenase (CDD) from Pseudomonas sp. strain P51, cloned into Escherichia coli DH5alpha(pTCB149) was able to oxidize cis-dihydrodihydroxy derivatives (cis-dihydrodiols) of dihydronaphthalene, indene, and four para-substituted toluenes to the corresponding catechols. During the incubatio... |
10574960 | The cyclization mechanism of cyclodextrin glycosyltransferase (CGTase) as revealed by a gamma-cyclodextrin-CGTase complex at 1.8-A resolution. | The enzyme cyclodextrin glycosyltransferase is closely related to alpha-amylases but has the unique ability to produce cyclodextrins (circular alpha(1-->4)-linked glucoses) from starch. To characterize this specificity we determined a 1.8-A structure of an E257Q/D229N mutant cyclodextrin glycosyltransferase in complex ... |
10572185 | Single-base mismatch detection based on charge transduction through DNA. | High-throughput DNA sensors capable of detecting single-base mismatches are required for the routine screening of genetic mutations and disease. A new strategy for the electrochemical detection of single-base mismatches in DNA has been developed based upon charge transport through DNA films. Double-helical DNA films on... |
10572180 | Thermodynamic comparison of PNA/DNA and DNA/DNA hybridization reactions at ambient temperature. | The thermodynamics of 13 hybridization reactions between 10 base DNA sequences of design 5'-ATGCXYATGC-3' with X, Y = A, C, G, T and their complementary PNA and DNA sequences were determined from isothermal titration calorimetry (ITC) measurements at ambient temperature. For the PNA/DNA hybridization reactions, the bin... |
10573526 | Prostaglandin E(1) protects against liver injury induced by Escherichia coli infection via a dominant Th2-like response of liver T cells in mice. | Prostaglandin E series (PGEs) are known to protect against lipopolysaccharide (LPS)-induced liver injury by down-regulating the production of inflammatory cytokines. We show here a novel mechanism whereby prostaglandin E(1) protects mice against liver injury after Escherichia coli infection. Prostaglandin E(1) administ... |
10570038 | Dopamine D4/D2 receptor selectivity is determined by A divergent aromatic microdomain contained within the second, third, and seventh membrane-spanning segments. | Conserved features of the sequences of dopamine receptors and of homologous G-protein-coupled receptors point to regions, and amino acid residues within these regions, that contribute to their ligand binding sites. Differences in binding specificities among the catecholamine receptors, however, must stem from their non... |
10569762 | Interaction of cationic peptides with lipoteichoic acid and gram-positive bacteria. | Compounds with antiendotoxin properties have been extensively studied for their potential as therapeutic agents for sepsis attributable to gram-negative bacteria. However, with the increasing incidence of gram-positive sepsis, there is interest in identifying compounds with a broad spectrum of action against both gram-... |
10569739 | Activity of monosaccharide lipid A analogues in human monocytic cells as agonists or antagonists of bacterial lipopolysaccharide. | The lipid A portion of bacterial lipopolysaccharide (LPS) plays a central role in the production of endotoxic mediators. Different responses between human and murine macrophages to lipid A-like structures have been indicated. We investigated a series of structurally related monosaccharide lipid A analogues for their po... |
10567553 | Identification of a portable repression domain and an E1A-responsive activation domain in Pax4: a possible role of Pax4 as a transcriptional repressor in the pancreas. | Pax4 is a paired-domain (PD)-containing transcription factor which plays a crucial role in pancreatic beta/delta-cell development. In this study, we characterized the DNA-binding and transactivation properties of mouse Pax4. Repetitive rounds of PCR-based selection led to identification of the optimal DNA-binding seque... |
10567215 | alpha5 subunit in Trypanosoma brucei proteasome can self-assemble to form a cylinder of four stacked heptamer rings. | The proteasomes have a central role in catalysing protein degradation among both prokaryotes and eukaryotes. The 20 S proteasome constitutes their catalytic core. In studying the structure of Trypanosoma brucei 20 S proteasomes, we isolated by two-dimensional (2D) gel electrophoresis a 27 kDa subunit protein with an es... |
10569293 | Imaging of carrageenan macrocycles and amylose using noncontact atomic force microscopy. | Samples of kappa-carrageenan, iota-carrageenan, and synthetic amylose have been examined by atomic force microscopy (AFM). All samples were spray deposited from aqueous solutions onto freshly cleaved mica, air dried, and imaged in air using noncontact atomic force microscopy (NCAFM). Images of single stranded amylose a... |
10564659 | Mutations affecting transmembrane segment interactions impair adhesiveness of E-cadherin. | Lateral clustering of E-cadherin molecules is required for the adhesive properties of this cell-cell adhesion molecule. Both the extracellular domain and the cytoplasmic region of E-cadherin were previously reported to contribute to lateral clustering, but little is known about a role of the transmembrane domain in thi... |
10561454 | Sialoforms of dipeptidylpeptidase IV from rat kidney and liver. | Dipeptidylpeptidase IV (DPP IV, CD26), a serine-type exo- and endopeptidase found in the cell surface membrane of many tissues, was employed as a model membrane glycoprotein to study the expression of sialoforms on cell surface glycoproteins. Native, enzymatically active DPP IV was purified from plasma membranes of kid... |
10556320 | A search for base analogs to enhance third-strand binding to 'inverted' target base pairs of triplexes in the pyrimidine/parallel motif. | Eight base analogs were tested as third strand residues in otherwise homopyrimidine strands opposite each of the 'direct' (A.T and G.C) and 'inverted' (T.A and C.G) Watson-Crick base pairs, using UV melting profiles to assess triplex stability. The target duplexes contained 20 A.T base pairs and a central test base pai... |
10556310 | Self-assembly of DNA-streptavidin nanostructures and their use as reagents in immuno-PCR. | The self-assembly of bis-biotinylated double-stranded DNA and the tetravalent biotin-binding protein streptavidin (STV) have been studied by non-denaturing gel electrophoresis and atomic force microscopy (AFM). The rapid self-assembly reproducibly generated populations of individual oligomeric complexes. Most strikingl... |
10559355 | Dynamin is required for recombinant adeno-associated virus type 2 infection. | Recombinant adeno-associated virus (rAAV) vectors for gene therapy of inherited disorders have demonstrated considerable potential for molecular medicine. Recent identification of the viral receptor and coreceptors for AAV type 2 (AAV-2) has begun to explain why certain organs may demonstrate higher efficiencies of gen... |
10559330 | Physical and functional interaction between the Y-box binding protein YB-1 and human polyomavirus JC virus large T antigen. | Y-box binding protein YB-1 is a member of a family of DNA and RNA binding proteins which have been shown to affect gene expression at both the transcriptional and translational levels. We have previously shown that YB-1 modulates transcription from the promoters of the ubiquitous human polyomavirus JC virus (JCV). Here... |
10559328 | Mutational analysis of bovine viral diarrhea virus RNA-dependent RNA polymerase. | Recombinant bovine viral diarrhea virus (BVDV) nonstructural protein 5B (NS5B) produced in insect cells has been shown to possess an RNA-dependent RNA polymerase (RdRp) activity. Our initial attempt to produce the full-length BVDV NS5B with a C-terminal hexahistidine tag in Escherichia coli failed due to the expression... |
10456232 | Glutamate receptor requirement for neuronal death from anoxia-reoxygenation: an in Vitro model for assessment of the neuroprotective effects of estrogens. | 1. Previous studies demonstrated that estrogens, specifically 17 beta-estradiol, the potent, naturally occurring estrogen, are neuroprotective in a variety of models including glutamate toxicity. The aim of the present study is twofold: (1) to assess the requirement for glutamate receptors in neuronal cell death associ... |
33867679 | Potassium and sodium measurements at clinical concentrations using phase-modulation fluorometry. | We describe the possibility of measuring sodium and potassium at the concentrations present in whole blood using lifetime-based sensing and phase-modulation fluorometry. The probe SBFO was shown to display changes in phase or modulation at sodium concentrations near 100 mM, and to be mostly independent of interfering e... |
10602200 | Controlled Self-Assembly of Cyclic Gold(I) Complexes: The First Family of Organometallic Catenanes. | The value of n in Ph(2)P(CH(2))(n)PPh(2) controls whether a simple ring or a [2]catenane is formed in the reaction with a digold(I) diacetylide. Simple macrocyclic gold complexes are obtained for n=2 and the family of organometallic [2]catenanes for n=4 and 5 (see structure); a mixture of these products as well as a th... |
10602191 | Shaping Solid-State Supramolecular Cavities: Chemically Induced Accordionlike Movement of gamma-Zirconium Phosphate Containing Polyethylenoxide Pillars. | The hydrophilic oxygen atoms of polyethylenoxide chains inserted as pillars in gamma-zirconium phosphate form hydrogen bonds with the acid groups of the host. As a result the pillars are almost perpendicular to the gamma layers. Upon changing the pH level of the supernatant solution the hydrogen bonds are broken and th... |
10556913 | Visualization of Surface Gelation Processes in a Doped Sol-Gel Glass. | Pulsed photoacoustic spectroscopy has enabled depth-resolved, in situ measurements of the chemical changes that occur in a sol-gel process to be examined. By use of beta-carotene as a probe to determine the efficiency of heat transfer to the immediate molecular environment in thin and thick samples, separate surface an... |
10556903 | A Supramolecular Tetra-Keggin Polyoxometalate | Giant polyoxometalates with catalytic, magnetic, and antiviral properties, which are in part attributable to their structures, are currently of great interest. Herein is described the synthesis and characterization of 1, a structurally novel tetrameric complex from Keggin ions (see picture). This complex is stable unde... |
10556900 | Gold(I) and Gold(0) Complexes of Phosphinine-Based Macrocycles. | A "CO-like matrix", showing coordination analogous to that of carbonyl groups, is provided by silacalix[4]phosphinine macrocycles. Reaction with Au(I) leads to the first gold(I) complexes of macrocycles, which can be reduced with sodium or potassium to the paramagnetic gold(0) complexes (an example is shown), as eviden... |
10556898 | Specific RNA Dinucleotide Cleavage by a Synthetic Calix | Large rate enhancements and considerable nucleobase specificity in the catalytic transesterification of RNA dinucleotides are observed with the calix[4]arene enzyme mimic 1-Zn(3) (the computer-generated model of the complex with GpG is shown). The higher activity toward GpG over ApA (factor of 160) originates from favo... |
10545380 | Influence of a natural and a synthetic inhibitor of factor XIIIa on fibrin clot rheology. | We investigated the origins of greater clot rigidity associated with FXIIIa-dependent cross-linking. Fibrin clots were examined in which cross-linking was controlled through the use of two inhibitors: a highly specific active-center-directed synthetic inhibitor of FXIIIa, 1,3-dimethyl-4,5-diphenyl-2[2(oxopropyl)thio]im... |
10545365 | Supramolecular structures of peptide assemblies in membranes by neutron off-plane scattering: method of analysis. | In a previous paper (Yang et al., Biophys. J. 75:641-645, 1998), we showed a simple, efficient method of recording the diffraction patterns of supramolecular peptide assemblies in membranes where the samples were prepared in the form of oriented multilayers. Here we develop a method of analysis based on the diffraction... |
10545357 | Gamma-aminobutyric acid increases the water accessibility of M3 membrane-spanning segment residues in gamma-aminobutyric acid type A receptors. | Gamma-aminobutyric acid type A (GABA(A)) receptors are members of the ligand-gated ion channel gene superfamily. Using the substituted cysteine accessibility method, we investigated whether residues in the alpha(1)M3 membrane-spanning segment are water-accessible. Cysteine was substituted, one at a time, for each M3 re... |
10534389 | Transport Properties of Cation Exchange Membranes in the Presence of Ether Compounds in Electrodialysis. | Ether compounds such as ethylene glycols with different molecular weights and crown ethers have good affinity to the cation exchange membranes, sulfonated styrene-divinylbenzene membrane (sodium ion form) and perfluorocarbon sodium sulfonate membrane. The impregnated amount of ethylene glycols in the membranes was high... |
11671289 | High-Dimensional Manganese(II) Compounds with Noncovalent and/or Covalent Bonds Derived from Flexible Ligands: Self-Assembly and Structural Transformation. | A hydrogen- and covalent-bonded 3D array, [Mn(bpe)(H(2)O)(4)](n)()(ClO(4))(2)(n)()(bpe)(4)(n)()(H(2)O)(2)(n)() (2) [bpe = 1,2-bis(4-pyridyl)ethane], a covalent-bonded 3D network, [Mn(bpe)(1.5)(H(2)O)(tp)](n)()(H(2)O)(n)() (3) [tp = terephthalate], and a covalent-bonded 2D sheet, [Mn(bpe)(N(3))(2)](n)() (4), have been s... |
11671276 | Four-Coordinate, Low-Spin (S = 0) and Six-Coordinate, High-Spin (S = 1) Nickel(II) Complexes of Tetraphenylporphyrins with beta-Pyrrole Electron-Withdrawing Substituents: Porphyrin-Core Expansion and Conformation. | To examine the porphyrin-core expansion and the conformational variations induced by a change in the coordination sphere of nickel(II) from four-coordinate, low-spin (S = 0) to six-coordinate, high-spin (S = 1), several nickel(II) derivatives of tetraphenylporphyrins, substituted in their beta-pyrrole positions with el... |
11671275 | Ligand Influences on Copper Cyanide Solid-State Architecture: Flattened and Fused "Slinky", Corrugated Sheet, and Ribbon Motifs in the Copper-Cyanide-Triazolate-Organoamine Family. | A series of novel composite inorganic-organic materials from the copper-cyanide-triazolate-organoamine system have been isolated and structurally characterized. An unusual interpenetrating layered structure type composed of fused and flattened "slinkies", [Cu(6)(CN)(5)(trz)] (1) (trz = triazolate, C(2)N(3)H(2)(-)), a c... |
11671241 | Metal Ion Dependent Molecular Inclusion Chemistry: Inclusion of p-Toluenesulfonate and p-Nitrophenolate within the Structure of Coordinated 1,4,7,10-Tetrakis((S)-2-hydroxy-3-phenoxypropyl)-1,4,7,10-tetraazacyclododecane. | The pendant donor macrocyclic ligand 1,4,7,10-tetrakis((S)-2-hydroxy-3-phenoxypropyl)-1,4,7,10-tetraazacyclododecane ((S)-thphpc12) has been synthesized in quantitative yield from cyclen (1,4,7,10-tetraazacyclododecane) and (2S)-(+)-3-phenoxy-1,2-epoxypropane. An X-ray diffraction study supports the result of molecular... |
12552693 | [A novel chiral selector in capillary electrophoresis--beta-cyclodextrin polymer]. | Three chiral selectors CM-beta-CD, EP-beta-CD, beta-CD were studied for the enatio-separation of three drugs under optimum conditions respectively. The results demonstrate that the resolving power for the drugs is as follows CM-beta-CD > EP-beta-CD > beta-CD, with the exception of lobeline. This is due to the--CH2COOCH... |
12552684 | [beta-Cyclodextrin bonded stationary phases for chiral separation in HPLC]. | A review of beta-cyclodextrin bonded stationary phases in chiral liquid chromatography is given, focusing on design and synthesis of beta-cyclodextrin bonded chiral stationary phases. Fifty-three references are presented in this paper. |
11212340 | Yeast aging research: recent advances and medical relevance. | The molecular mechanisms of aging are most fully understood for the budding yeast Saccharomyces cerevisiae. Recent advances in our understanding of aging in this organism have enabled researchers to answer some fundamental questions about the aging process. Is aging due to a multitude of 'mechanisms' or can there be a ... |
11212331 | Evolution of bacterial pathogenesis. | The evolution of bacteria is associated with continuous generation of novel genetic variants. The major driving forces in this process are point mutations, genetic rearrangements, and horizontal gene transfer. A large number of human and animal bacterial pathogens have evolved the capacity to produce virulence factors ... |
11212314 | Hyaluronan synthases: fascinating glycosyltransferases from vertebrates, bacterial pathogens, and algal viruses. | Hyaluronan (or hyaluronic acid or hyaluronate; HA) is a polysaccharide found in the extracellular matrix of vertebrate tissues and in the surface coating of certain Streptococcus and Pasteurella bacterial pathogens. At least one algal virus directs its host to produce HA on the cell surface early in infection. HA synth... |
11212308 | Scaffolding proteins and their role in viral assembly. | Scaffolding proteins are proteins that are required to catalyse, regulate or modulate some step in the assembly of a macromolecular complex. They associate specifically with the nascent protein complex during assembly, but are subsequently removed, and are absent from the mature structure. Scaffolding proteins have bee... |
11212306 | Kainate receptor pharmacology and physiology. | Glutamate is the primary neurotransmitter in the central nervous system. One of the classes of ionotropic glutamate receptors is kainate receptors. Recent developments in the pharmacology of kainate receptors have resulted in the emergence of several selective agonists and antagonists. These compounds have allowed scie... |
10542100 | Allosteric selection of ribozymes that respond to the second messengers cGMP and cAMP. | RNA transcripts containing the hammerhead ribozyme have been engineered to self-destruct in the presence of specific nucleoside 3',5'-cyclic monophosphate compounds. These RNA molecular switches were created by a new combinatorial strategy termed 'allosteric selection,' which favors the emergence of ribozymes that rapi... |
10876840 | [The effect of methylated cyclodextrin on pertussis toxin accumulation in a Bordetella pertussis culture in a bioreactor]. | The results obtained in the study of the influence methylated cyclodextrin (beta CD) on the growth of B. pertussis and the accumulation of pertussis toxin in the course of submerged batch cultivation in a bioreactor are presented. As demonstrated by these results, the presence of beta CD in the culture medium in a dose... |
10825989 | Improved synthesis of epothilone B employing alkylation of an alkyne for assembly of subunits. | [formula: see text] A strategy for assembling the two principal modules of epothilone B was developed that merges an allylic bromide with a terminal acetylene to fabricate the C10-C11 bond of the macrocycle. The resulting alkyne was semihydrogenated to give a seco ester previously employed in our total synthesis of epo... |
10748748 | [Dissolution and signs of supersaturation of nimodipine in aqueous solutions of the cyclodextrins, alpha-CD, HP-alpha-CD, M-beta-CD and HP-gamma-CD]. | The dissolution curves of the substance of the calcium antagonist nimodipine in aqueous solutions of four cyclodextrins were determined at ambient temperature in the course of 14 days. The used cyclodextrins were alpha-cyclodextrin (alpha-CD), hydroxypropyl-alpha-cyclodextrin (HP-alpha-CD), methyl-beta-cyclodextrin (M-... |
10748746 | [Studies of local anesthetics. CL. Models of the dependence of local anesthetic effectiveness of basic esters of alkoxy-substituted phenylcarbamic acids on capacity factor k']. | On the basis of proposed six models of the dependence of local anaesthetic effectiveness of series of alkoxysubstituted derivatives of phenylcarbamic acid, this activity was studies in dependence on the capacity factor k' as the parameter of lipophilicity. The most suitable models proved to be y = (Cx + Ci).k' for surf... |
10707284 | [Comparative study of the crystallin supramolecular structure in the carp, frog, and rat lenses by small-angle roentgen ray scattering]. | The supramolecular structure of crystallins in intact ocular lenses of carp, frog and rat as well as in the interior (nuclear) and outer (cortical) parts of these lenses was studied by the small-angle X-ray scattering method. The results show that the supramolecular structure of crystallins substantially varies both in... |
10708314 | Spectrophotometric method for determination of bifunctional macrocyclic ligands in macrocyclic ligand-protein conjugates. | A simple spectrophotometric assay for determination of bifunctional polyazacarboxylate-macrocyclic ligands of different sizes that are conjugated to proteins has been developed for: 12-membered macrocycle DOTA (2-[4-nitrobenzyl]-1, 4, 7, 10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) and analogs, the 15-membe... |
10703995 | Photodegradation of inclusion complexes of isradipine with methyl-beta-cyclodextrin. | The paper presents results of the studies on photochemical decomposition of isradipine (IS) and its liquid inclusion complexes with methyl-beta-cyclodextrin (M-betaCD). The process of photodegradation was assessed by the methods of UV spectrophotometry, HPLC (reverse-phase) and HPTLC (normal phase) chromatographic meth... |
10701417 | Stereoselective determination of trihexyphenidyl in human serum by LC-ESI-MS. | The antiparkinsonian drug trihexyphenidyl (THP) is currently manufactured and administered as a racemate. However, stereochemistry can play significant role in the drug's pharmacokinetics, biotransformation, metabolism, interaction with cellular and tissue components and overall effect on human body. It is necessary to... |
10654218 | Acute neuromuscular respiratory failure after ICU discharge. Report of five patients. | <h4>Objective</h4>To describe a syndrome of acute neuromuscular respiratory failure (NM-ARF) caused by ICU-acquired acute myopathy and neuropathy.<h4>Design</h4>Case series.<h4>Setting</h4>General Regional University Hospital in Brescia, Italy.<h4>Patients</h4>Five adult patients with NM-ARF after prolonged ICU stay an... |
10638398 | Bioavailability of intranasal formulations of dihydroergotamine. | <h4>Objective</h4>A comparison of the pharmacokinetic properties of two novel intranasal preparations of dihydroergotamine mesilate (DHEM) with a commercially available intranasal preparation.<h4>Methods</h4>Two intranasal formulations of DHEM in combination with randomly methylated beta-cyclodextrin (RAMEB) were prepa... |
10635555 | Transcriptional regulation of the Bacillus ohbensis cyclodextrin glucanotransferase gene in B. subtilis. | The expression of the cyclodextrin glucanotransferase (CGTase) gene (cgt) of Bacillus ohbensis, when introduced into an alpha-amylase-defective strain of B. subtilis on a multicopy plasmid, pHY300PLK, was induced in the presence of starch and was subject to catabolite repression by glucose as well as in the original st... |
10632077 | Stability of diclofenac sodium in the inclusion complex with beta-cyclodextrin in the solid state. | The aim of this study was to characterize the thermal stability of diclofenac sodium both alone and in the inclusion complex with beta-cyclodextrin in the solid state, by determination of the number of the products of its decomposition, which were identified by GC-MS. The molar ratio of diclofenac sodium in the inclusi... |
10632071 | In search of new chemical entities with spermicidal and anti-HIV activities. | Several compounds belonging to 2-isoxazolines (4,5a-c), isoxazoles (3,6a-c) and 1-amino-1-cycloalkyl-2-substituted phenyl ethanes (16-18,a-e) have been synthesised and found to possess spermicidal activity. Out of these a couple of compounds (5a and 6a) exhibit anti-HIV activity. |
10632057 | Molecular recognition of tyrosinyl adenylate analogues by prokaryotic tyrosyl tRNA synthetases. | Molecular modelling and synthetic studies have been carried out on tyrosinyl adenylate and analogues to probe the interactions seen in the active site of the X-ray crystal structure of tyrosyl tRNA synthetase from Bacillus stearothermophilus, and to search for new inhibitors of this enzyme. Micromolar and sub-micromola... |
10632051 | Synthesis, characterization and anticonvulsant activity of enaminones. Part 6: Synthesis of substituted vinylic benzamides as potential anticonvulsants. | A comparison of enaminones from various unsubstituted and p-substituted benzamides to the analogous benzylamines has been undertaken with the aim of elucidating the essential structural parameters necessary for anticonvulsant activity. Initial studies on methyl 4-N-(benzylamino)-6-methyl-2-oxocyclohex-3-en-1-oate, 3a, ... |
10632045 | Thrombin receptor-activating peptides (TRAPs): investigation of bioactive conformations via structure-activity, spectroscopic, and computational studies. | The thrombin receptor (PAR-1) is an unusual transmembrane G-protein coupled receptor in that it is activated by serine protease cleavage of its extracellular N-terminus to expose an agonist peptide ligand, which is tethered to the receptor itself. Synthetic peptides containing the agonist motif, such as SFLLRN for huma... |
10625461 | Role of heme in structural organization of cytochrome c probed by semisynthesis. | The heme prosthetic group of cytochrome c is covalently attached to the protein through thioether bonds to two cysteine side chains. The role of covalent heme attachment to cytochrome c is not understood, and most heme proteins bind the prosthetic group by iron ion ligation and tertiary interactions only. A two-armed a... |
10625455 | Mechanism of inhibition of cathepsin K by potent, selective 1, 5-diacylcarbohydrazides: a new class of mechanism-based inhibitors of thiol proteases. | The nature of the inhibition of thiol proteases by a new class of mechanism-based inhibitors, 1,5-diacylcarbohydrazides, is described. These potent, time-dependent, active-site spanning inhibitors include compounds that are selective for cathepsin K, a cysteine protease unique to osteoclasts. The 1,5-diacylcarbohydrazi... |
10624567 | Use of the triazolotriazine [3H]ZM 241385 as a radioligand at recombinant human A2B adenosine receptors. | Radiolabeled ZM 241385 (4-(2-[7-amino-2- ¿furyl¿¿1,2,4¿triazolo¿2,3-a¿¿1,3,5¿triazin-5-ylaminoethyl)p henol), has previously been used as a high affinity radioligand for the labeling of A2A adenosine receptors in cell membranes. Another subtype, the A2B receptor, is the least well-defined subtype of adenosine receptors... |
10612642 | Clinical outcome and its predictors in 1560 patients with critical leg ischaemia. Chronic Critical Leg Ischaemia Group. | <h4>Objective</h4>to assess the predictivity of clinical variables in patients with chronic critical leg ischaemia (CLI). Design observational prospective cohort study.<h4>Methods</h4>the i.c.a.i. (ischemia critica degli arti inferiori) trial database was used to assess the impact of patients' history, cardiovascular r... |
10610765 | Structure-specific binding of the two tandem HMG boxes of HMG1 to four-way junction DNA is mediated by the A domain. | We have investigated the nature of the "structure-specific" binding of the tandem A and B HMG boxes of high mobility group protein 1 (HMG1) to four-way junction DNA. AB didomain binding favours the open, planar form of the junction, as shown by reaction with potassium permanganate. Site-directed cleavage of the DNA by ... |
10610758 | Suppression analysis of positive control mutants of NifA reveals two overlapping promoters for Klebsiella pneumoniae rpoN. | Activation of gene expression relies on direct molecular interactions between the RNA polymerase and transcription factors. Eubacterial enhancer-binding proteins (EBPs) activate transcription by binding to distant sites and, simultaneously, contacting the sigma(54)-holoenzyme form of the RNA polymerase (Esigma(54)). Th... |
10611648 | Survey of the 1998 optical biosensor literature. | The utilization of optical biosensors to study molecular interactions continues to expand. In 1998, 384 articles relating to the use of commercial biosensors were published in 130 different journals. While significant strides in new applications and methodology were made, a majority of the biosensor literature is of ra... |
10611647 | Towards understanding the mechanisms of molecular recognition by computer simulations of ligand-protein interactions. | The thermodynamic and kinetic aspects of molecular recognition for the methotrexate (MTX)-dihydrofolate reductase (DHFR) ligand-protein system are investigated by the binding energy landscape approach. The impact of 'hot' and 'cold' errors in ligand mutations on the thermodynamic stability of the native MTX-DHFR comple... |
10611646 | Conformational homogeneity in molecular recognition by proteolytic enzymes. | Crystal structures for several hundred protease-inhibitor complexes have been analysed and their superimpositions have been used to demonstrate a universal relationship between inhibitor/substrate conformation and molecular recognition by all aspartic, serine, cysteine and metallo proteases. Proteases universally recog... |
10611645 | Molecular recognition events involved in the activation of the growth hormone receptor by growth hormone. | Binding of growth hormone (GH) to its receptor (GHR) is a well-studied example of molecular recognition between a cytokine and its receptor. Extensive mutagenesis studies and several crystal structures have defined the key interactive amino acid residues that are involved in binding and subsequent receptor dimerization... |
10611644 | Characterization of the sequential non-covalent and covalent interactions of the antitumour antibiotic hedamycin with double stranded DNA by NMR spectroscopy. | Hedamycin, a member of the pluramycin class of antitumour antibiotics, consists of a planar anthrapyrantrione chromophore to which is attached two aminosugar rings at one end and a bisepoxide-containing sidechain at the other end. Binding to double-stranded DNA is known to involve both reversible and non-reversible mod... |
10611643 | Effects of 5-[S-(2,4-dinitrophenyl)-thio]-2'-deoxyuridine analog incorporation on the structure and stability of DNA hybrids: implications for the design of nucleic acid probes. | Labeled nucleic acid probes are used as diagnostic tools by detecting changes in gene expression upon hybridization to target RNAs or DNAs that are related to specific disease genes. 5-[S-(2, 4-Dinitrophenyl)-thio]-2'-deoxyuridine analog represents an excellent nucleic acid label, containing the DNP group which functio... |
10612032 | Cyclodextrin inclusion complexes of antimycotics intended to act in the oral cavity--drug supersaturation, toxicity on TR146 cells and release from a delivery system. | The dissolution rate, the toxicity and the release from chewing gum of miconazole and econazole cyclodextrin products and complexes were investigated. The dissolution rate studies showed that an amorphous miconazole hydroxypropyl-beta-cyclodextrin product gave drug supersaturation, whereas drug supersaturation was not ... |
10608711 | Enantiomeric separation of fluoxetine and norfluoxetine in plasma and serum samples with high detection sensitivity capillary electrophoresis. | A capillary electrophoresis method was optimized for the stereoselective analysis of the antidepressant drug fluoxetine and its main demethylated metabolite norfluoxetine using a cyclodextrin-modified sodium phosphate buffer at pH 2.5. The combination of a neutral and a negatively charged cyclodextrin, dimethylated-bet... |
10608710 | Experimental design for enantioselective separation of celiprolol by capillary electrophoresis using sulfated beta-cyclodextrin. | A capillary zone electrophoresis method was developed for the enantioseparation of celiprolol enantiomers, using a sulfated beta-cyclodextrin (beta-CD) as a chiral selector. The use of a coated capillary was necessary to achieve stable and reproducible enantioseparations. A central composite design was applied to optim... |
10608709 | Enantiomeric separation of glycyl dipeptides by capillary electrophoresis with cyclodextrins as chiral selectors. | Uncharged cyclodextrins were tested as chiral selectors for the enantiomeric separation of 13 glycyl dipeptides with capillary electrophoresis. Initial experiments were performed on 10 mmol/L of a cyclodextrin in 0.1 mol/L phosphoric acid -0.088 mol/L triethanolamine. Some of the resolved dipeptides were nonaromatic, w... |
10608708 | Enantioseparation of derivatized amino acids by capillary isoelectric focusing using cyclodextrin complexation. | Enantioseparation of dansylated as well as 6-aminoquinolyl-N-hydroxysuccinimidylcarbamate (AQC)-derivatized amino acids by means of capillary isoelectric focusing using various cyclodextrin derivatives is demonstrated. Separation is based on the enantioselective shift of the isoelectric points upon complexation with th... |
10608705 | Using affinity capillary electrophoresis to evaluate average binding constant of 18-mer diphosphotyrosine peptide to antiphosphotyrosine Fab. | We used affinity electrophoresis in capillaries to investigate the interaction between a monovalent antiphosphotyrosine antibody fragment, antigen-binding fragment (Fab), and a divalent antigen (dAg), an 18-mer diphosphopeptide phosphorylated on two-site tyrosine residues. The migration shift behavior of Fab in electro... |
10605055 | Properties and the inclusion behavior of 6-O-alpha-D-galactosyl- and 6-O-alpha-D-mannosyl-cyclodextrins. | The novel heterogeneous branched cyclodextrins (CDs), 6-O-alpha-D- galactosyl-alpha, -beta, and -gamma CDs (Gal-alpha, -beta, and -gamma CDs) and 6-O-alpha-D-mannosyl-alpha, -beta, and -gamma CDs (Man-alpha, -beta, and -gamma CDs) dissolved sufficiently in water and in 10-50% (v/v) methanol aqueous solutions, as did th... |
10602299 | Investigation of cyclomaltooligosaccharide-bound 6-(4-methoxyphenyl)imidazo[1,2-a]pyrazin-3(7H)-one for enhanced chemiluminescence. | The chemiluminescence compound 2-methyl-6-(4-methoxyphenyl)imidazo[1, 2-a]pyrazin-3(7H)-one (MCLA) was attached to cyclomaltooligosaccharides (cyclodextrins) through a single spacer by the formation of an amide bond. The properties of oxygen-induced chemiluminescence of the synthesized cyclodextrin-bound MCLA were inve... |
10596361 | Effect of aging on the dissolution stability of glibenclamide/beta-cyclodextrin complex. | The effect of aging on the physicochemical stability of glibenclamide (GB)/beta-cyclodextrin (CD) systems and tablets made with CD-complexed GB was studied. Infrared (IR) spectrometry and X-ray diffraction analyses showed that the properties of the products were unaffected even after a storage period of 4 years, except... |
10596356 | Sugar-branched-cyclodextrins as injectable drug carriers in mice. | The purpose of this study was to investigate stable complexation of drug in blood by sugar-branched-beta-cyclodextrins (beta-CDs) such as glucose (glu)- or galactose (gal)-branched-beta-CDs and the pharmacokinetic disposition of drug in sugar-branched-beta-CD complex. Complexation of steroidal drugs in sugar-branched-b... |
10544151 | A yeast screen system for aromatase inhibitors and ligands for androgen receptor: yeast cells transformed with aromatase and androgen receptor. | Endocrine disruptors are hormone mimics that modify hormonal action in humans and animals. It is thought that some endocrine disruptors modify estrogen and androgen action in humans and animals by suppressing aromatase activity. Aromatase cytochrome P450 is the key enzyme that converts C19 androgens to aromatic C18 est... |
10595541 | Immunochemical evidence that cholesteryl ester transfer protein and bactericidal/permeability-increasing protein share a similar tertiary structure. | Cholesteryl ester transfer protein (CETP) plays an important role in plasma lipoprotein metabolism through its ability to transfer cholesteryl ester, triglyceride, and phospholipid between lipoproteins. CETP is a member of a gene family that also includes bactericidal/permeability-increasing protein (BPI). The crystal ... |
10595534 | The role of position a in determining the stability and oligomerization state of alpha-helical coiled coils: 20 amino acid stability coefficients in the hydrophobic core of proteins. | We describe here a systematic investigation into the role of position a in the hydrophobic core of a model coiled-coil protein in determining coiled-coil stability and oligomerization state. We employed a model coiled coil that allowed the formation of an extended three-stranded trimeric oligomerization state for some ... |
10595525 | The interaction of neurotrophins with the p75NTR common neurotrophin receptor: a comprehensive molecular modeling study. | Neurotrophins are a family of proteins with pleiotropic effects mediated by two distinct receptor types, namely the Trk family, and the common neurotrophin receptor p75NTR. Binding of four mammalian neurotrophins, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and neurotroph... |
10591766 | [Optimal timing for secondary surgery in polytrauma patients: an evaluation of 4,314 serious-injury cases]. | <h4>Introduction</h4>It has been argued that secondary operations in multiple trauma patients impose an additional systemic burden, representing an additional risk of organ dysfunction. We investigated whether the timing of a secondary operation of > 3 h duration is related with the development of organ dysfunction.<h4... |
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