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15106988 | Structural effects of the lone pair on lead(II), and parallels with the coordination geometry of mercury(II). Does the lone pair on lead(II) form H-bonds? Structures of the lead(II) and mercury(II) complexes of the pendant-donor macrocycle DOTAM (1,4,7,10-tetrakis(carbamoylmethyl)-1,4,7,10-tetraazacyclododecane). | The synthesis and structures of [Pb(DOTAM)](ClO4)2.4.5H2O (1) and [Hg(DOTAM)](ClO4)2.0.5CH3OH.1.5H2O (2) are reported, where DOTAM is 1,4,7,10-tetrakis(carbamoylmethyl)-1,4,7,10-tetraazacyclododecane. Compound 1 is triclinic, space group P, a = 12.767(3) A, b = 13.528(2) A, c = 18.385(3) A, alpha = 101.45(2) degrees, b... |
15106981 | Variable pi-bonding in iron(II) porphyrinates with nitrite, CO, and tert-butyl isocyanide: characterization of [Fe(TpivPP)(NO2)(CO)]-. | The addition of the strongly pi-bonding ligands CO or tert-butyl isocyanide to the low-spin five-coordinate iron(II) nitrite species [Fe(TpivPP)(NO2)]- (TpivPP = picket fence porphyrin) gives two new six-coordinate species [Fe(TpivPP)(NO2)(CO)]- and [Fe(TpivPP)(NO2)(t-BuNC)]-. These species have been characterized by s... |
15106978 | Metallic macrocycle with a 1,3-alternate calix[4]arene phosphorus ligand. | The preparation of an 1,3-alternate calix[4]arene phosphorus ligand, 25,27-bis(2-(diphenylphosphino)ethoxy)-26,28-bis(1-propyloxy)calix[4]arene (3), is presented. Ligand 3 is obtained in three steps in 64% overall yield. Reaction of 3 with [Rh(cot)2]BF4 produced the encapsulated rhodium complex [Rh[(P,P)-diphen-calix[4... |
15106971 | Solution dynamics and stability of lanthanide(III) (S)-2-(p-nitrobenzyl)DOTA complexes. | Addition of a benzyl substituent to the macrocyclic ring of DOTA has a substantial impact on the conformational ring flipping motion of the macrocycle in the resulting LnDOTA complexes. The p-NO2-benzyl substituent in the Ln(p-NO2-Bn-DOTA)- complexes lies in an equatorial position and effectively "locks" the conformati... |
15106967 | Cyclophosphazenes as nodal ligands in coordination polymers. | Herein, we show that cyclotriphosphazenes carrying organo amino side chains, (RNH)6P3N3 [R = n-propyl (1), cyclohexyl (2), benzyl (3)], and (C4H8N)6P3N3 (4) produce supramolecular coordination compounds in conjunction with silver salts by formation of linear N-Ag-N connections via nitrogen centers of the phosphazene ri... |
15106965 | A systematic evaluation of molecular recognition phenomena. 4. Selective binding of dicarboxylic acids to hexaazamacrocyclic ligands based on molecular flexibility. | The host-guest interaction between four hexaaza macrocyclic ligands (3,6,9,17,20,23-hexaazatricyclo[23.3.1.1]triaconta-1(29),11,13,15 (30),25(27)-hexaene (Bd), 3,6,9,16,19,22-hexaazatricyclo[22.2.2.2]triaconta-1(27),11(30),12,14(29),24(28),25-hexaene (P2), 3,7,11,19,23,27-hexaazatricyclo[27.3.1.1]tetratriaconta-1(33),1... |
15106959 | A new, convenient synthesis of the linear phosphazene salt [Cl3P=N=PCl3]Cl: preparation of higher linear homologues [Cl3P=N-(PCl2=N)x=PCl3]Cl (x = 1-3) and the 16-membered macrocycle [NCCl(NPCl2)3]2. | An improved synthetic route to the linear phosphazene salt [Cl3P=N=PCl3]Cl is reported. This species is a useful precursor to higher linear homologues and also to heterocycles such as the 16-membered carbophosphazene macrocycle [NCCl(NPCl2)3]2. |
15105131 | Dose-dependent pharmacokinetics of itraconazole after intravenous or oral administration to rats: intestinal first-pass effect. | The dose-dependent pharmacokinetics of itraconazole after intravenous (10, 20, or 30 mg/kg) and oral (10, 30, or 50 mg/kg) administration and the first-pass effects of itraconazole after intravenous, intraportal, intragastric, and intraduodenal administration at a dose of 10 mg/kg were evaluated in rats. After intraven... |
15105112 | Novel polysulfated galactose-derivatized dendrimers as binding antagonists of human immunodeficiency virus type 1 infection. | Evidence indicates that galactosyl ceramide (GalCer) and its 3'-sulfated derivative, sulfatide (SGalCer), may act as alternate coreceptors for human immunodeficiency virus type 1 (HIV-1) in CD4(-) cells. Glycosphingolipids (GSLs) may also be necessary for fusion of HIV-1 and host cell membranes. Using an enzyme-linked ... |
15105110 | Biophysical characterization of endotoxin inactivation by NK-2, an antimicrobial peptide derived from mammalian NK-lysin. | NK-2, a membrane-acting antimicrobial peptide, was derived from the cationic core region of porcine NK-lysin and consists of 27 amino acid residues. It adopts an amphipathic, alpha-helical secondary structure and has been shown to interact specifically with membranes of negatively charged lipids. We therefore investiga... |
15103622 | Atomic insight into the CD4 binding-induced conformational changes in HIV-1 gp120. | The entry of HIV-1 into a target cell requires gp120 and receptor CD4 as well as coreceptor CCR5/CXCR4 recognition events associated with conformational changes of the involved proteins. The binding of CD4 to gp120 is the initiation step of the whole process involving structural rearrangements that are crucial for subs... |
15102796 | Importance of the ornibactin and pyochelin siderophore transport systems in Burkholderia cenocepacia lung infections. | Previously, orbA, the gene encoding the outer membrane receptor for ferric-ornibactin, was identified in Burkholderia cenocepacia K56-2, a strain which produces ornibactin, salicylic acid, and negligible amounts of pyochelin. A K56-2 orbA mutant was less virulent than the parent strain in a rat agar bead infection mode... |
15102756 | Analysis of haptoglobin and hemoglobin-haptoglobin interactions with the Neisseria meningitidis TonB-dependent receptor HpuAB by flow cytometry. | Neisseria meningitidis expresses a two-component TonB-dependent receptor, HpuAB, which mediates heme-iron (Hm-Fe) acquisition from hemoglobin and hemoglobin-haptoglobin complexes. Due to genetic polymorphisms in the human haptoglobin gene, haptoglobin (and hemoglobin-haptoglobin) exists as three structurally distinct p... |
15099708 | Functional identification of ASCT1 neutral amino acid transporter as the predominant system for the uptake of L-serine in rat neurons in primary culture. | The uptake of L-serine, a nonessential amino acid known to be transported by the neutral amino acid transporter system ASC, was studied in primary cultures of rat neurons and astrocytes, and compared with that in human embryonic kidney (HEK293) cells transfected with rat ASCT1 cDNA. We first cloned neutral amino acid t... |
14998368 | Getting into position: the catalytic mechanisms of protein ubiquitylation. | The role of protein ubiquitylation in the control of diverse cellular pathways has recently gained widespread attention. Ubiquitylation not only directs the targeted destruction of tagged proteins by the 26 S proteasome, but it also modulates protein activities, protein-protein interactions and subcellular localization... |
14750901 | The anti-Müllerian hormone type II receptor: insights into the binding domains recognized by a monoclonal antibody and the natural ligand. | Anti-Müllerian hormone (AMH) [also called Müllerian inhibiting substance (MIS)] is a member of the transforming growth factor-beta family. AMH and its type II receptor (AMHR-II) are involved in the regression of the Müllerian ducts in the male embryo, and in gonadal functions in the adult. AMH is also known to be a mar... |
14733615 | Elucidation of eukaryotic elongation factor-2 contact sites within the catalytic domain of Pseudomonas aeruginosa exotoxin A. | Pseudomonas aeruginosa produces the virulence factor, ETA (exotoxin A), which catalyses an ADP-ribosyltransferase reaction of its target protein, eEF2 (eukaryotic elongation factor-2). Currently, this protein-protein interaction is poorly characterized and this study was aimed at identifying the contact sites between e... |
14715083 | Quantitative analysis of nucleotide modulation of DNA binding by DnaC protein of Escherichia coli. | In this study, we have presented the first report of Escherichia coli DnaC protein binding to ssDNA (single stranded DNA) in an apparent hexameric form. DnaC protein transfers DnaB helicase onto a nascent chromosomal DNA replication fork at oriC, the origin of E. coli DNA replication. In eukaryotes, Cdc6 protein may pl... |
15093597 | The influence of absorption enhancers on nasal absorption of acyclovir. | The objective of this work was to increase the nasal absorption of acyclovir by using absorption enhancers. Acyclovir was selected as a model drug. A rat in situ nasal perfusion technique was utilized in the investigation to examine the rate and extent of absorption of acyclovir. In vitro enzymatic drug degradation stu... |
15093596 | Skin compatibility of cyclodextrins and their derivatives: a comparative assessment using a corneoxenometry bioassay. | Few studies have been performed to assess the risk of skin damage by cyclodextrins (CD) and they have yielded contradictory results. The present study was conducted using the corneoxenometry bioassay on human stratum corneum to compare the skin compatibility of CD currently used in pharmaceutical preparations (betaCD, ... |
15090428 | Cannabinoids and glaucoma. | Glaucoma is one of the leading causes of blindness in the world. In spite of the diverse therapeutic possibilities, new and better treatments for glaucoma are highly desirable. Cannabinoids effectively lower the intraocular pressure (IOP) and have neuroprotective actions. Thus, they could potentially be useful in the t... |
15089812 | Effect of St John's wort and ginseng on the pharmacokinetics and pharmacodynamics of warfarin in healthy subjects. | <h4>Unlabelled</h4>M: The aim of this study was to investigate the effect of St John's wort and ginseng on the pharmacokinetics and pharmacodynamics of warfarin.<h4>Methods</h4>This was an open-label, three-way crossover randomized study in 12 healthy male subjects, who received a single 25-mg dose of warfarin alone or... |
15084354 | Cyclodextrin-enhanced solubilization of pentachlorophenol in water. | The solubilization of pentachlorophenol (PCP) by beta-cyclodextrin (beta-CD) and three of its most used derivatives, methyl-beta-cyclodextrin (MCD), hydroxypropyl-beta-cyclodextrin (HPCD) and carboxymethyl-beta-cyclodextrin (CMCD), has been investigated. The formation of soluble inclusion complexes between PCP and cycl... |
15082764 | Epidermal growth factor receptor stimulation activates the RNA binding protein CUG-BP1 and increases expression of C/EBPbeta-LIP in mammary epithelial cells. | The transcription factor CCAAT/enhancer binding protein beta (C/EBP beta) is a key regulator of growth and differentiation in many tissues. C/EBP beta is expressed as several distinct protein isoforms (LAP1, LAP2, and LIP) whose expression is regulated by alternative translational initiation at downstream AUG start sit... |
15081581 | Effects of the allosteric modulator SCH-202676 on adenosine and P2Y receptors. | The G protein-coupled receptor allosteric modulator SCH-202676 (N-(2,3-diphenyl-1,2,4-thiadiazol-5-(2H)-ylidene)methanamine), which affects a wide range of structurally unrelated G protein-coupled receptors, has highly divergent effects on purine receptors. SCH-202676 inhibited radioligand binding to human adenosine A(... |
15081354 | Path to equality strewn with roX. | Male flies hypertranscribe most genes along their single X chromosome to match the output of females with two X chromosomes. This is mediated by chromatin modifications carried out by the MSL complex composed of noncoding roX RNA and at least five MSL proteins. New results indicate that one of these subunits, the MOF a... |
15081875 | Diisothiocyanate derivatives as potent, insurmountable antagonists of P2Y6 nucleotide receptors. | The physiological role of the P2Y(6) nucleotide receptor may involve cardiovascular, immune and digestive functions based on the receptor tissue distribution, and selective antagonists for this receptor are lacking. We have synthesized a series of symmetric aryl diisothiocyanate derivatives and examined their ability t... |
15081395 | Expression and regulation of phospholipase D isoforms in sphingosine and phorbol ester-stimulated glioma C6 cells. | Previously we have reported that in glioma C6 cells, sphingosine stimulatory effect on phospholipase D (PLD) activity is independent of protein kinase C [Cell. Signal. 12 (2000) 399]. In this paper we have shown that this effect was also GTPgammaS independent and was completely inhibited by the plasma membrane methyl-b... |
15078966 | CCAAT/enhancer binding protein alpha binds to the Epstein-Barr virus (EBV) ZTA protein through oligomeric interactions and contributes to cooperative transcriptional activation of the ZTA promoter through direct binding to the ZII and ZIIIB motifs during induction of the EBV lytic cycle. | The Epstein-Barr virus (EBV)-encoded ZTA protein interacts strongly with and stabilizes the cellular CCAAT/enhancer binding protein alpha (C/EBPalpha), leading to the induction of p21-mediated G(1) cell cycle arrest. Despite the strong interaction between these two basic leucine zipper (bZIP) family proteins, the ZTA a... |
15078937 | Epistatic effects of immunoglobulin GM and KM allotypes on outcome of infection with hepatitis C virus. | Immunoglobulin GM and KM allotypes-genetic markers of gamma and kappa chains, respectively-are associated with immune responsiveness to several infectious pathogens and with survival in certain viral epidemics. We hypothesized that GM and KM allotypes affect the outcome of hepatitis C virus (HCV) infection. To test thi... |
15078928 | The hypervariable region 1 of the E2 glycoprotein of hepatitis C virus binds to glycosaminoglycans, but this binding does not lead to infection in a pseudotype system. | The hypervariable region 1 (HVR1) of hepatitis C virus (HCV) E2 envelope glycoprotein is a 27-amino-acid sequence located at its N terminus. In this study, we investigated the functional role of HVR1 for interaction with the mammalian cell surface. The C-terminal truncated E2 glycoprotein was appended to a transmembran... |
15072971 | Translocation of caveolin regulates stretch-induced ERK activity in vascular smooth muscle cells. | Mechanical stress contributes to vascular disease related to hypertension. Activation of ERK is key to mediating cellular proliferation and vascular remodeling in response to stretch stress. However, the mechanism by which stretch mediates ERK activation in the vascular tissue is still unclear. Caveolin, a major compon... |
15069663 | Comparison of the chiral separation of amino-acid derivatives by a teicoplanin and RN-beta-CD CSPs using waterless mobile phases: Factors that enhance resolution. | A variety of compounds containing amines (i.e., amino acids, amino alcohols, etc.) were chemically derivatized with a variety of electrophilic tagging reagents to elucidate the chiral recognition sites on a teicoplanin-bonded chiral stationary phase (CSP) and on R-naphthylethylcarbamate-beta-cyclodextrin (RN-beta-CD)-b... |
15069659 | Spacer length effect of a chiral stationary phase based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid. | A new chiral stationary phase (CSP) containing 11 methylene-unit spacer was prepared by bonding (+)-(18-crown-6)-2,3,11,12-carboxylic acid to aminoundecylsilica gel. The new CSP was superior to the one containing three methylene-unit spacer in the resolution of alpha-amino acids, beta-amino acids, amines, and amino alc... |
15064143 | Histological evidence supporting a role for the striatal neurokinin-1 receptor in methamphetamine-induced neurotoxicity in the mouse brain. | Several studies have documented the effect of methamphetamine (METH) on the toxicity of the dopamine (DA) terminals of the striatum but only a few studies have assessed the damaging effects of METH on striatal neurons postsynaptic to the nigrostriatal DA terminals. In the present study, we employed histological methods... |
15051444 | Polyethylene glycol-polyamidoamine dendritic micelle as solubility enhancer and the effect of the length of polyethylene glycol arms on the solubility of pyrene in water. | Unimolecular dendritic micelles designed as solubility enhancers were obtained by coupling polyethylene glycol (PEG) to Starburst polyamidoamine (PAMAM) dendrimers. Micelles-750, -2000, and -5000 have a generation 3.0 dendrimer core (32 primary amine end groups) and PEG arms with molecular weights of 750, 2000, and 500... |
15048822 | GEMDOCK: a generic evolutionary method for molecular docking. | We have developed an evolutionary approach for flexible ligand docking. This approval, GEMDOCK, uses a Generic Evolutionary Method for molecular DOCKing and an empirical scoring function. The former combines both discrete and continuous global search strategies with local search strategies to speed up convergence, wher... |
15048821 | Melittin as model system for probing interactions between proteins and cyclodextrins. | Cylcodextrin sugars are cyclic sugars that have a hydrophilic exterior and a hydrophobic center. This enables cyclodextrins to solubilize hydrophobic molecules in aqueous media. Cyclodextrins may inhibit aggregation by intercalating surface aromatic residues and competing with interprotein aromatic clusters (pi-pi inte... |
15033345 | Characterization of the convulsant action of pregnenolone sulfate. | Pregnenolone sulfate (PS) is an endogenous neurosteroid synthesized by glial cells, which acts as a potent convulsant when injected intracerebroventricularly and intraperitoneally. PS is found in relatively high concentrations in the hippocampus. But its convulsant action in the hippocampus has not been characterized. ... |
15034905 | Absolute configuration of chiral terpenes in marking pheromones of bumblebees and cuckoo bumblebees. | The absolute configurations of citronellol, 2,3-dihydrofarnesol, and 2,3-dihydrofarnesal in male marking pheromones of seven species of bumblebees and cuckoo bumblebees were determined by enantioselective gas chromatography on a capillary column coated with 60% heptakis(2,3-di-O-acetyl-6-O-TBDMS)-beta-cyclodextrin in p... |
15027105 | Calculation of electrostatic interaction energies in molecular dimers from atomic multipole moments obtained by different methods of electron density partitioning. | Accurate and fast evaluation of electrostatic interactions in molecular systems is still one of the most challenging tasks in the rapidly advancing field of macromolecular chemistry, including molecular recognition, protein modeling and drug design. One of the most convenient and accurate approaches is based on a Bucki... |
15017137 | Interpretation of NMR relaxation properties of Pin1, a two-domain protein, based on Brownian dynamic simulations. | Many important proteins contain multiple domains connected by flexible linkers. Inter-domain motion is suggested to play a key role in many processes involving molecular recognition. Heteronuclear NMR relaxation is sensitive to motions in the relevant time scales and could provide valuable information on the dynamics o... |
18007431 | Self-assembly of [2]rotaxane exploiting reversible Pt(II)- pyridine coordinate bonds. | A dinuclear self-assembled cationic macrocycle based on Pt(II)-N(pyridine) coordinative bonds and having competitive triflate anions, as metal counterions, is used in the construction of [2]rotaxane and [2]pseudorotaxane architectures assisted by hydrogen bonding. The kinetic lability of the Pt(II)-N(pyridine) coordina... |
15119954 | Applications of nanoparticles in biology and medicine. | Nanomaterials are at the leading edge of the rapidly developing field of nanotechnology. Their unique size-dependent properties make these materials superior and indispensable in many areas of human activity. This brief review tries to summarise the most recent developments in the field of applied nanomaterials, in par... |
15131368 | A heterometallic polymeric complex: [Cu2(N3)2(medpt)2[Ni(CN)4]]n [medptis bis(3-aminopropyl)methylamine]. | The structure of the title compound, catena-poly[[di-micro-azido-kappa(4)N(1):N(1)-bis[[bis(3-aminopropyl)methylamine-kappa(3)N]copper(II)]]-micro-cyano-[dicyanonickel(II)]-micro-cyano], [Cu(2)(N(3))(2)(medpt)(2)[Ni(CN)(4)]](n) [medpt is bis(3-aminopropyl)methylamine, C(7)H(19)N(2)] or [Cu(2)Ni(CN)(4)(N(3))(2)(C(7)H(19... |
15115799 | Mismatching base-pair dependence of the kinetics of DNA-DNA hybridization studied by surface plasmon fluorescence spectroscopy. | Two single-stranded DNAs consisting of complementary base pairs except for one mismatching base pair (MM1) can form double-stranded DNA by molecular recognition. This type of duplex is not as stable as that formed by MM0. In order to add to a better understanding of the physical mechanism of the hybridization and disso... |
15115797 | A novel replicating circular DNAzyme. | 10-23 DNAzyme has the potential to suppress gene expressions through sequence-specific mRNA cleavage. However, the dependence on exogenous delivery limits its applications. The objective of this work is to establish a replicating DNAzyme in bacteria using a single-stranded DNA vector. By cloning the 10-23 DNAzyme into ... |
15115733 | Oligodendrocytes, their progenitors and other neuroglial cells in the aging primate cerebral cortex. | In a previous study it was found that with age there is an increase in the frequency of paranodal profiles of myelinated nerve fibers in the cerebral cortex of monkeys. This indicates that there is an increase in the number of internodal myelin segments, and raises the question of whether additional oligodendrocytes ar... |
15113873 | Assessment of reliability of microarray data and estimation of signal thresholds using mixture modeling. | DNA microarray is an important tool for the study of gene activities but the resultant data consisting of thousands of points are error-prone. A serious limitation in microarray analysis is the unreliability of the data generated from low signal intensities. Such data may produce erroneous gene expression ratios and ca... |
15117937 | Identification and activity of a series of azole-based compounds with lactate dehydrogenase-directed anti-malarial activity. | Plasmodium falciparum, the causative agent of malaria, relies extensively on glycolysis coupled with homolactic fermentation during its blood-borne stages for energy production. Selective inhibitors of the parasite lactate dehydrogenase (LDH), central to NAD(+) regeneration, therefore potentially provide a route to new... |
15136812 | Cooperative molecular recognition of dyes by dyad and triad cyclodextrin-crown ether conjugates. | Three beta-cyclodextrin (beta-CyD) derivatives with crown ether units, that is N-(4'-benzo-15-crown-5)-6-imino-6-deoxy-beta-CyD (2), 6,6'-[N-(4,4'-dibenzo-18-crown-6)-imino]-bridged bis(beta-CyD)(3), and 2,2'-[O-(4',5'-benzo-15-crown-5)-ethyl]-bridged bis (beta-CyD)(5), were synthesized as cooperative recognition recep... |
15118103 | Close agreement between the orientation dependence of hydrogen bonds observed in protein structures and quantum mechanical calculations. | Hydrogen bonding is a key contributor to the exquisite specificity of the interactions within and between biological macromolecules, and hence accurate modeling of such interactions requires an accurate description of hydrogen bonding energetics. Here we investigate the orientation and distance dependence of hydrogen b... |
15117976 | CD43 regulation of T cell activation is not through steric inhibition of T cell-APC interactions but through an intracellular mechanism. | CD43 is a large heavily glycosylated protein highly expressed on T cells and actively excluded from the immunological synapse through interactions with ezrin-radixin-moesin proteins. Due to its size and charge, it has been proposed that the CD43 ectodomain acts as a physical barrier to T cell-APC interactions. We have ... |
15252605 | Mononucleotide recognition by cyclic trinuclear palladium(II) complexes containing 4,7-phenanthroline N,N bridges. | Reaction of [(dach)Pd(NO3)2] entities (dach = (R,R)-1,2-diaminocyclohexane, (S,S)-1,2-diaminocyclohexane) and 4,7-phenanthroline (phen) providing, respectively, 90 and 120 degrees bond angles, leads to the formation of two novel positively charged homochiral cyclic trinuclear metallacalix[3]arene species [((R,R)-1,2-di... |
15107466 | Selective stimulation of caveolar endocytosis by glycosphingolipids and cholesterol. | Internalization of some plasma membrane constituents, bacterial toxins, and viruses occurs via caveolae; however, the factors that regulate caveolar internalization are still unclear. Here, we demonstrate that a brief treatment of cultured cells with natural or synthetic glycosphingolipids (GSLs) or elevation of choles... |
15153229 | Protective ventilation of patients with acute respiratory distress syndrome. | In a recent issue of the British Journal of Anaesthesia, Moloney and Griffiths reviewed clinically pertinent issues surrounding the management of the acute respiratory distress syndrome (ARDS) patient, particularly as it pertains to the treatment of ventilator induced/associated lung injury (VILI). In addition to highl... |
15107492 | Probing minor groove recognition contacts by DNA polymerases and reverse transcriptases using 3-deaza-2'-deoxyadenosine. | Standard nucleobases all present electron density as an unshared pair of electrons to the minor groove of the double helix. Many heterocycles supporting artificial genetic systems lack this electron pair. To determine how different DNA polymerases use the pair as a substrate specificity determinant, three Family A poly... |
15104799 | Special considerations in the treatment of patients with bipolar disorder and medical co-morbidities. | BACKGROUND: The pharmacological treatment of bipolar disorder has dramatically improved with multiple classes of agents being used as mood-stabilizers, including lithium, anticonvulsants, and atypical antipsychotics. However, the use of these medications is not without risk, particularly when a patient with bipolar dis... |
15103445 | Low-temperature investigation of the growth mechanism of alkylsiloxane self-assembled monolayers. | The growth behavior of self-assembled monolayer films strongly depends on parameters such as solvent, water concentration in the solvent, substrate type, and deposition method. A further parameter, the temperature, is of particular importance. It has been found that growth kinetics, size, and shape of the structures ob... |
15136819 | Halide anion directed assembly of luminescent pseudorotaxanes. | A series of new photo-active rhenium(i) bipyridyl based pseudorotaxane complexes is assembled via halide anion templation. |
15128438 | The mechanism of prion strain propagation. | Studies of mammalian prion diseases such as bovine spongiform encephalopathy have suggested that different strains consist of prion proteins with different conformations. Two recent studies of yeast prions have now formally demonstrated that multiple stable protein conformations are the basis of strain variation. |
15252603 | Binding sites on the outside of metallo-supramolecular architectures; engineering coordination polymers from discrete architectures. | Aggregation of metallo-supramolecular architectures through additional coordination is explored by introducing metal-binding units onto the outside of the supramolecular architectures. This is achieved within the framework of our imine-based approach to supramolecular architecture, by replacing the pyridylimine units w... |
15136816 | One molecule per particle method for functionalising nanoparticles. | A mean of one biotinylated dextran molecule per particle is conjugated to 15 nm gold nanoparticles, by a process of self-assembly, which depends on the relationship between dextran molecular weight and particle size. |
15131364 | 1,4-Diazabicyclo[2.2.2]octane-1,4-diium trichromate. | The title compound, (C(6)H(14)N(2))[Cr(3)O(10)], consists of a diazabicyclo[2.2.2]octane-1,4-diium cation and a discrete trichromate anion linked by an N-H.O hydrogen bond. Three CrO(4) tetrahedra are joined via shared O atoms to form the trichromate anion. Supramolecular rings, which can be described by the graph-set ... |
15169246 | Hierarchical self-assembly of GaAs/AlGaAs quantum dots. | A novel structure containing self-assembled, unstrained GaAs quantum dots is obtained by combining solid-source molecular beam epitaxy and atomic-layer precise in situ etching. Photo-luminescence (PL) spectroscopy reveals light emission with very narrow inhomogeneous broadening and clearly resolved excited states at hi... |
15136804 | Synthesis of indaphyrins: meso-tetraarylsecochlorin-based porphyrinoids containing direct o-phenyl-to-beta-linkages. | The synthesis of indaphyrins, novel meso-tetraarylsecochlorin-derived chromophores incorporating o-phenyl-to-beta-linkages, is described. Oxidative diol cleavage of meso-tetraaryl-2,3-dihydroxy-2,3-chlorins results in the formation of a secochlorin bisaldehyde. Depending on the reaction conditions during the ring cleav... |
15100411 | Molecular recognition of the nucleosomal "supergroove". | Chromatin is the physiological substrate in all processes involving eukaryotic DNA. By organizing 147 base pairs of DNA into two tight superhelical coils, the nucleosome generates an architecture where DNA regions that are 80 base pairs apart on linear DNA are brought into close proximity, resulting in the formation of... |
15096509 | The hepatitis E virus open reading frame 3 protein activates ERK through binding and inhibition of the MAPK phosphatase. | The hepatitis E virus causes acute viral hepatitis endemic in much of the developing world and is a serious public health problem. However, due to the lack of an in vitro culture system or a small animal model, its biology and pathogenesis are poorly understood. We have shown earlier that the ORF3 protein (pORF3) of he... |
15096499 | Lipid raft disruption triggers protein kinase C and Src-dependent protein kinase D activation and Kidins220 phosphorylation in neuronal cells. | Kidins220 (kinase D-interacting substrate of 220 kDa) is a novel neurospecific protein recently cloned as the first substrate for the Ser/Thr kinase protein kinase D (PKD). Herein we report that Kidins220 is constitutively associated to lipid rafts in PC12 cells, rat primary cortical neurons, and brain synaptosomes. Im... |
15096523 | F1F0 ATP synthase subunit c is a substrate of the novel YidC pathway for membrane protein biogenesis. | The Escherichia coli YidC protein belongs to the Oxa1 family of membrane proteins that have been suggested to facilitate the insertion and assembly of membrane proteins either in cooperation with the Sec translocase or as a separate entity. Recently, we have shown that depletion of YidC causes a specific defect in the ... |
15252609 | Cyclam-based dendrimers as ligands for lanthanide ions. | We have investigated the complexation of lanthanide ions (Nd3+, Eu3+, Gd3+, Tb3+, Dy3+) with three cyclam-based ligands (cyclam = 1,4,8,11-tetraazacyclotetradecane), namely 1,4,8,11-tetrakis(naphthylmethyl)cyclam (1), and two dendrimers consisting of a cyclam core appended with four dimethoxybenzene and eight naphthyl ... |
15087489 | Enhanced cellular uptake of a triplex-forming oligonucleotide by nanoparticle formation in the presence of polypropylenimine dendrimers. | We used polypropylenimine dendrimers for delivering a 31 nt triplex-forming oligonucleotide (ODN) in breast, prostate and ovarian cancer cell lines, using 32P-labeled ODN. Dendrimers enhanced the uptake of ODN by approximately 14-fold in MDA-MB-231 breast cancer cells, compared with control ODN uptake. Dendrimers exert... |
15087488 | Genetic re-engineering of Saccharomyces cerevisiae RAD51 leads to a significant increase in the frequency of gene repair in vivo. | Oligonucleotides can be used to direct the alteration of single nucleotides in chromosomal genes in yeast. Rad51 protein appears to play a central role in catalyzing the reaction, most likely through its DNA pairing function. Here, we re-engineer the RAD51 gene in order to produce proteins bearing altered levels of kno... |
15278135 | Dendrimers as guests in molecular recognition phenomena. | Dendrimers are highly branched macromolecules which may engage in host-guest interactions, acting as either hosts or guests; this review is specifically concerned with the binding behavior of dendrimers containing single or multiple guest residues interacting with individual, freely diffusing hosts. |
15252596 | Synthesis and characterisation of macrocyclic palladium(II)-sodium(I) complexes: generation of an unusual metal-mediated electron delocalisation. | Reaction of sodium perchlorate-crown ether derivative (LH2) complex [Na2LH2](ClO4)2 (1) with palladium acetate afforded two related compounds of macrocyclic palladium(II)-sodium(I) dimeric tetranuclear complexes, [Pd2Na2L2(mu-OH2)2](ClO4)2(CH2Cl2)3 (2) and [Pd2Na2(L-)2](CH3CN)2(C3H6O)2 (3) and their structures were cha... |
15084739 | Fas-disabling small exocyclic peptide mimetics limit apoptosis by an unexpected mechanism. | Fas ligand- (FasL) mediated apoptosis is an important element of tissue-specific organ damage. We have developed biologically active small exocyclic peptide mimetics that disable apoptotic functions of Fas. The most effective mimetic binds to both its receptor and FasL with comparable affinity. In vitro, the most effec... |
15084673 | Peptide-linked molecular beacons for efficient delivery and rapid mRNA detection in living cells. | Real-time visualization of specific endogenous mRNA expression in vivo has the potential to revolutionize medical diagnosis, drug discovery, developmental and molecular biology. However, conventional liposome- or dendrimer-based cellular delivery of molecular probes is inefficient, slow, and often detrimental to the pr... |
15082751 | Behavior of alpha-, beta-, and gamma-cyclodextrins and their derivatives on an in vitro model of blood-brain barrier. | Cyclodextrins (CDs) can be envisaged to cure some diseases related to the brain, but the behavior of these compounds toward the blood-brain barrier (BBB) remains largely unexplored to envisage such clinical applications. To fulfill this gap, the toxicity and endothelial permeability for native, methylated, and hydroxyp... |
15116188 | Hexakis(isopropylthio)-1,5-hexadien-3-yne and its fluorescent Ag(I) coordination polymers: assembly of helicates with thioether sites. | A new thioether-rich ligand with a conjugated dienyne backbone and its fluorescent Ag(I) coordination networks have been synthesized and characterized by single crystal X-ray diffraction studies, which reveal that the supramolecular architectures of the networks contain assembled helicates with thioether sites. |
15116187 | Exploiting phenyl embraces and pi-stacking in the assembly of arrays of tetraphenylphosphonium p-sulfonatocalix[4]arene. | Phenyl embraces involving tetraphenylphosphonium cations feature in complexes of p-sulfonatocalix[4]arene where a phenyl ring of a cation is included in the cavity of the calixarene. The overall structures are based on pseudo-polymorphic supramolecular arrays and their formation is templated or induced by lanthanide io... |
15079089 | Crystal structure of the von Willebrand factor A domain of human capillary morphogenesis protein 2: an anthrax toxin receptor. | Anthrax toxin is released from Bacillus anthracis as three monomeric proteins, which assemble into toxic complexes at the surface of receptor-bearing host cells. One of the proteins, protective antigen (PA), binds to receptors and orchestrates the delivery of the other two (the lethal and edema factors) into the cytoso... |
15078817 | p27Kip1 modulates cell migration through the regulation of RhoA activation. | The tumor suppressor p27(Kip1) is an inhibitor of cyclin/cyclin-dependent kinase (CDK) complexes and plays a crucial role in cell cycle regulation. However, p27(Kip1) also has cell cycle-independent functions. Indeed, we find that p27(Kip1) regulates cell migration, as p27(Kip1)-null fibroblasts exhibit a dramatic decr... |
15079081 | Palladium-catalyzed carbocyclization of 1,6-enynes leading to six-membered rings or oxidized five-membered trifluoroacetates. | We describe palladium-catalyzed carbocyclization of 1,6-enynes leading to six-membered rings by water-originated hydride addition. Mechanistic features of this anomalous carbocyclization and isolation of a chiral five-membered C-Pd intermediate as an oxidized form of trifluoroacetate are also reported. |
15079055 | Structural elements responsible for conversion of streptavidin to a pseudoenzyme. | Avidin enhances the hydrolysis of biotinyl p-nitrophenyl ester (BNP) under mild alkaline conditions, whereas streptavidin prevents hydrolysis of BNP up to pH 12. Recently, we imposed hydrolytic activity on streptavidin by rational mutagenesis, based on the molecular elements responsible for the hydrolysis by avidin. Th... |
15083257 | Blockade of mesolimbic dopamine D3 receptors inhibits stress-induced reinstatement of cocaine-seeking in rats. | <h4>Rationale</h4>The dopamine (DA) D3 receptor is preferentially expressed in the mesolimbic system. We have previously shown that selective D3 receptor blockade by the novel D3 antagonist SB-277011A inhibits cocaine's reinforcing action and cocaine-induced reinstatement of cocaine-seeking behavior.<h4>Objective</h4>I... |
15131380 | Two oxazane macrocycles. | The 20-membered ring in 1,7,11,17-tetraoxa-2,6,12,16-tetraazacycloeicosane tetrahydrochloride, C(12)H(32)N(4)O(4)(4+).4Cl(-), adopts an endo conformation, while the 18-membered ring in 1,6,10,15-tetraoxa-2,5,11,14-tetraazacyclooctadecane tetrahydrochloride, C(10)H(28)N(4)O(4)(4+).4Cl(-), lies about an inversion centre ... |
15075389 | A DNA polymerase beta mutant from colon cancer cells induces mutations. | Previous investigations have shown that approximately 35% of the 90 tumors analyzed to date contain mutations within the DNA polymerasebeta (pol beta) gene. The existence of pol beta mutations in a substantial fraction of human tumors studied suggests a link between DNA pol beta and cancer. A DNA pol beta variant, in w... |
15073272 | Polyunsaturated fatty acids including docosahexaenoic and arachidonic acid bind to the retinoid X receptor alpha ligand-binding domain. | Nuclear receptors (NRs) constitute a large and highly conserved family of ligand-activated transcription factors that regulate diverse biological processes such as development, metabolism, and reproduction. As such, NRs have become important drug targets, and the identification of novel NR ligands is a subject of much ... |
15073181 | Disruption of pancreatic beta-cell lipid rafts modifies Kv2.1 channel gating and insulin exocytosis. | In pancreatic beta-cells, the predominant voltage-gated Ca(2+) channel (Ca(V)1.2) and K(+) channel (K(V)2.1) are directly coupled to SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein (SNAP) receptor) proteins. These SNARE proteins modulate channel expression and gating and closely associate these chan... |
15073040 | Localization of pacemaker channels in lipid rafts regulates channel kinetics. | Lipid rafts are discrete membrane subdomains rich in sphingolipids and cholesterol. In ventricular myocytes a function of caveolae, a type of lipid rafts, is to concentrate in close proximity several proteins of the beta-adrenergic transduction pathway. We have investigated the subcellular localization of HCN4 channels... |
15073326 | Zr[bis(salicylidene)ethylenediaminato]-mediated Baeyer-Villiger oxidation: stereospecific synthesis of abnormal and normal lactones. | Baeyer-Villiger oxidation of racemic bicyclic cyclobutanones with Zr[bis(salicylidene)ethylenediaminato] (salen) complex 1 as catalyst in the presence of a urea-hydrogen peroxide adduct was found to proceed enantiospecifically. The enantiotopos selection in the oxidation was governed primarily by the Zr(salen) catalyst... |
15070825 | Effect of adding cholesterol to bull sperm membranes on sperm capacitation, the acrosome reaction, and fertility. | When cholesterol is added to sperm membranes before cryopreservation, higher percentages of motile and viable cells are recovered after thawing. However, because one of the first steps in sperm capacitation is cholesterol efflux from the sperm plasma membrane, adding cholesterol to enhance cryosurvival may retard sperm... |
15105914 | Probing the interaction of the biotin-avidin complex with the relaxivity of biotinylated Gd-DTPA. | A biotinylated Gd-DTPA complex is designed to study the biotin-avidin complexation using the longitudinal relaxivity of this new MRI label, which illustrates the use of MRI contrast agents to probe the formation of supramolecular assemblies in water. |
15069062 | Rapid evolution of beta-glucuronidase specificity by saturation mutagenesis of an active site loop. | Protein engineers have widely adopted directed evolution as a design algorithm, but practitioners have not come to a consensus about the best method to evolve protein molecular recognition. We previously used DNA shuffling to direct the evolution of Escherichia coli beta-glucuronidase (GUS) variants with increased beta... |
15116176 | Synthesis of peptide-nanotube platinum-nanoparticle composites. | Nanotubes prepared by the self-assembly of D-Phe-D-Phe molecules are investigated by electron microscopy and Monte Carlo simulations; the nanotubes appear to be porous and are capable of forming novel peptide-nanotube platinum-nanoparticle composites. |
15105930 | Intra- and intermolecular complexation in C6 monoazacoronand substituted cyclodextrins. | The preparation of 6(A)-deoxy-6(A)-(6-(2-(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)acetamido)hexylamino)-alpha-cyclodextrin, 3, 6(A)-deoxy-6(A)-(6-(2-(1,4,7,10,13-pentaoxa-16-azacyclooctadecan-16-yl)acetamido)hexylamino)-alpha-cyclodextrin, 4, and their beta-cyclodextrin analogues, 5 and 6, are described. (1)H (60... |
15064755 | Molecular recognition of BMP-2 and BMP receptor IA. | Bone morphogenetic protein-2 (BMP-2) and other members of the TGF-beta superfamily regulate the development, maintenance and regeneration of tissues and organs. Binding epitopes for these extracellular signaling proteins have been defined, but hot spots specifying binding affinity and specificity have so far not been i... |
15198542 | Solubilizing poorly soluble antimycotic agents by emulsification via a solvent-free process. | The purpose of this study was to formulate itraconazole and ketoconazole as oil/water emulsions for parenteral delivery by using a solvent-free homogenization process, namely SolEmuls (solubilization by emulsification) technology. The drugs were incorporated in the commercial emulsion Lipofundin MCT 20%, composed of a ... |
15066989 | Heme distortion modulated by ligand-protein interactions in inducible nitric-oxide synthase. | The catalytic center of nitric-oxide synthase (NOS) consists of a thiolate-coordinated heme macrocycle, a tetrahydrobiopterin (H4B) cofactor, and an l-arginine (l-Arg)/N-hydroxyarginine substrate binding site. To determine how the interplay between the cofactor, the substrates, and the protein matrix housing the heme r... |
15116211 | Synthesis and noncovalent polymerization of self-complementary hydrogen-bonding supramolecular synthons: N,N'-disubstituted 4,6-diamino-pyrimidin-2(1H)-ones. | A series of self-complementary N,N'-disubstituted 4,6-diaminopyrimidin-2(1H)-ones self-assemble in organic solvents to form a robust and linear supramolecular polymer network via DDA.AAD hydrogen-bonding. |
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