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12970435
Evolutionary pressure of a receptor competitor selects different subgroup a avian leukosis virus escape variants with altered receptor interactions.
A complex interaction between the retroviral envelope glycoproteins and a specific cell surface protein initiates viral entry into cells. The avian leukosis-sarcoma virus (ALV) group of retroviruses provides a useful experimental system for studying the retroviral entry process and the evolution of receptor usage. In t...
12970425
Characterization of the rhesus cytomegalovirus US28 locus.
Human cytomegalovirus (CMV) US28 (and the related open reading frame [ORF] US27) are G-protein-coupled receptor homologs believed to play a role in viral pathogenesis. In vitro, US28 has been shown to bind and internalize ligands, as well as activate intracellular signaling in response to certain chemokines, and to ini...
12970408
Proteasome activator PA28gamma-dependent nuclear retention and degradation of hepatitis C virus core protein.
Hepatitis C virus (HCV) core protein plays an important role in the formation of the viral nucleocapsid and a regulatory protein involved in hepatocarcinogenesis. In this study, we have identified proteasome activator PA28gamma (11S regulator gamma) as an HCV core binding protein by using yeast two-hybrid system. This ...
12970134
Scavenger receptor class B type I (SR-BI) in pig enterocytes: trafficking from the brush border to lipid droplets during fat absorption.
<h4>Background</h4>Scavenger receptor class B type I (SR-BI) is known to mediate cellular uptake of cholesterol from high density lipoprotein particles and is particularly abundant in liver and steroidogenic tissues. In addition, SR-BI expression in the enterocyte brush border has also been reported but its role in the...
12951105
Electrostatic interaction of pi-acidic amides with hydrogen-bond acceptors.
Interactions between N-methylacetamide (NMA) and N-methylated derivatives of uracil, isocyanurate and barbituric acid have been studied using ab initio methods at the local MP2/6-31G** level of theory. The results were compared to similar interactions between the oxygen atom of NMA and the pi-clouds of perfluorobenzene...
12945055
Crystallographic analysis of an "anticalin" with tailored specificity for fluorescein reveals high structural plasticity of the lipocalin loop region.
The artificial lipocalin FluA with novel specificity toward fluorescein was derived via combinatorial engineering from the bilin-binding protein, BBP by exchange of 16 amino acids in the ligand pocket. Here, we describe the crystal structure of FluA at 2.0 A resolution in the space group P2(1) with two protein-ligand c...
12945050
Host-guest scale of left-handed polyproline II helix formation.
Despite the clear importance of the left-handed polyproline II (PPII) helical conformation in many physiologically important processes as well as its potential significance in protein unfolded states, little is known about the physical determinants of this conformation. We present here a scale of relative PPII helix-fo...
12941564
Construction of a molecular imprinting catalyst using target analogue template and its application for an amperometric fructosylamine sensor.
Molecular imprinting technology is becoming a versatile tool for preparing tailor-made molecular recognition elements. However, inherent problems of the molecular imprinting technology include the availability and preparation of template molecules. We recently reported artificial enzyme sensors for fructosylamines cons...
12923809
Comprehensive strategy for chiral separations using sulfated cyclodextrins in capillary electrophoresis.
This review focuses on the emerging role of sulfated cyclodextrins in the capillary electrophoretic (CE) separation of chiral analytes. Since being introduced as enantioselective agents for CE in 1995, these anionic additives have continued to demonstrate remarkable application universality. The broad spectrum of chira...
12923806
Supramolecular exciton chirality of carotenoid aggregates.
The conventional organic chemistry concept of chirality relates to single molecules. This article deals with cases in which exciton chirality is generated by the interaction of associated carotenoids. The handed property responsible for exciton signals in these systems is due to the alignment of neighboring molecules h...
12921228
Exploring biochemistry and cellular biology with protein libraries.
Polypeptide libraries cast a broad net for defining enzyme and binding protein specificities. In addition to uncovering rules for molecular recognition, the binding preferences and functional group tolerances from such libraries can reveal mechanisms underlying biochemical and cellular processes. Ligands obtained from ...
15107911
The influence of low-level laser therapy on biomodulation of collagen and elastic fibers.
The study of low-level laser therapy upon extracellular matrix elements is important to understand the wound healing process under this agent. However, little is known about the interference of laser light in relation to collagen and elastic fibers. Cutaneous wounds were performed on the back of 72 Wistar rats and a Ga...
12907137
Effects of orally administered OP-1206 alpha-CD with loxoprofen-Na on walking dysfunction in the rat neuropathic intermittent claudication model.
An orally active prostaglandin E1 analogue, OP-1206 alpha-CD improves walking dysfunction in the rat spinal stenosis model. Loxoprofen-Na, a non-steroidal anti-inflammatory drug, is used to relieve chronic pain in patients with lumbar spinal canal stenosis. To determine whether the OP-1206 alpha-CD in combination with ...
12896843
Potential of enzyme mimics in biomimetic sensors: a modified-cyclodextrin as a dehydrogenase enzyme mimic.
This paper reports the application of a dehydrogenase enzyme mimic as a biomimetic sensor. The model compound investigated was a beta-cyclodextrin (beta-CD) derivative with a nicotinamide group attached to the secondary face of a beta-CD (Fig. 1g). It was envisaged that the nicotinamide group would act as the electron ...
15007665
Monodomain and polydomain helicoids in chiral liquid-crystalline phases and their biological analogues.
Many natural composites exhibit an architecture known as twisted plywood which imparts to them a superior set of physical properties. The origin of this structure is complex and not yet understood. However, it is thought to involve a lyotropic chiral nematic liquid-crystalline mesophase. Indeed, striking structural sim...
14758985
New fuzzy logic strategies for bio-molecular recognition.
The concepts of molecular similarity and molecular complementarity, playing important roles in the broad field of molecular recognition, are chemical problems, in which the eyeball technique used by a human observer is very successful but which are very hard to code into a computer algorithm. Based on the model of mole...
14754507
Peroxisome biogenesis and the role of protein import.
Peroxisomes are metabolic organelles with enzymatic content that are found in virtually all cells and are involved in beta-oxidation of fatty acids, hydrogen peroxide-based respiration and defence against oxidative stress. The steps of their biogenesis involves "peroxins", proteins encoded by PEX genes. Peroxins are in...
14519593
Inhibition of endocytosis causes phosphorylation (S256)-independent plasma membrane accumulation of AQP2.
Inhibition of clathrin-mediated endocytosis by expression of a GTPase-deficient dynamin mutant (dynamin-2/K44A) for 16 h results in an accumulation of plasma membrane aquaporin-2 (AQP2) in epithelial cells stably transfected with wild-type AQP2. We now show a similar effect of K44A dynamin in LLC-PK1 cells transfected ...
14519759
The human dopamine transporter forms a tetramer in the plasma membrane: cross-linking of a cysteine in the fourth transmembrane segment is sensitive to cocaine analogs.
Using cysteine cross-linking, we demonstrated previously that the dopamine transporter (DAT) is at least a homodimer, with the extracellular end of transmembrane segment (TM) 6 at a symmetrical dimer interface. We have now explored the possibility that DAT exists as a higher order oligomer in the plasma membrane. Cyste...
14519851
Nucleation-dependent conformational conversion of the Y145Stop variant of human prion protein: structural clues for prion propagation.
One of the most intriguing disease-related mutations in human prion protein (PrP) is the Tyr to Stop codon substitution at position 145. This mutation results in a Gerstmann-Straussler-Scheinker-like disease with extensive PrP amyloid deposits in the brain. Here, we provide evidence for a spontaneous conversion of the ...
14519850
Nuclear localization of pyrrole-imidazole polyamide-fluorescein conjugates in cell culture.
A series of hairpin pyrrole-imidazole polyamide-fluorescein conjugates were synthesized and assayed for cellular localization. Thirteen cell lines, representing 11 human cancers, one human transformed kidney cell line, and one murine leukemia cell line, were treated with 5 microM polyamide-fluorescein conjugates for 10...
14532661
[1,3-Bis(4-nitrophenyl)triazenido](triphenylphosphine)gold(I).
In the title complex, [Au(C(12)H(8)N(5)O(4))(C(18)H(15)P)], the coordination geometry about the Au(I) ion is linear, with one deprotonated 1,3-bis(4-nitrophenyl)triazenide ion, [O(2)NC(6)H(4)N=N-NC(6)H(4)NO(2)](-), acting as a monodentate ligand (two-electron donor), and one neutral triphenylphosphine molecule completi...
14517351
Self-organization by selection: generation of a metallosupramolecular grid architecture by selection of components in a dynamic library of ligands.
Self-organization by selection is implemented in the generation of a tetranuclear [2 x 2] grid-type metallosupramolecular architecture from its components. It occurs through a two-level self-assembly involving two dynamic processes: reversible covalent bound connection and reversible metal ion coordination. Thus, mixin...
14512422
SeqA protein stimulates the relaxing and decatenating activities of topoisomerase IV.
The SeqA protein, which prevents overinitiation of chromosome replication, has been suggested to also participate in the segregation of chromosomes in Escherichia coli. Using a bacterial two-hybrid system, we found that SeqA interacts with the ParC subunit of topoisomerase IV (topo IV), a type II topoisomerase involved...
14586088
Supramolecular aggregation in 4,4'-bipyridin-1,1'-ium dichloride, 4,4'-bipyridin-1,1'-ium dinitrate and 4,4'-bipyridin-1-ium bromide.
4,4'-Bipyridin-1,1'-ium dichloride [C(10)H(10)Cl(2)N(2) (I)] and 4,4'-bipyridin-1,1'-ium dinitrate [C(10)H(10)N(4)O(6) (II)] have been prepared and the crystal structures determined at 90.0 (2) K. Molecules of (I) are linked by two chlorine-bridged, three-centered N-H...Cl hydrogen bonds into chains along the b axis. T...
14512516
Insights into peptide nucleic acid (PNA) structural features: the crystal structure of a D-lysine-based chiral PNA-DNA duplex.
Peptide nucleic acids (PNAs) are oligonucleotide analogues in which the sugar-phosphate backbone has been replaced by a pseudopeptide skeleton. They bind DNA and RNA with high specificity and selectivity, leading to PNA-RNA and PNA-DNA hybrids more stable than the corresponding nucleic acid complexes. The binding affin...
14512291
Mitochondrial calcium uptake stimulates nitric oxide production in mitochondria of bovine vascular endothelial cells.
Although nitric oxide (NO) is a known modulator of cell respiration in vascular endothelium, the presence of a mitochondria-specific nitric oxide synthase (mtNOS) in these cells is still a controversial issue. We have used laser scanning confocal microscopy in combination with the NO-sensitive fluorescent dye DAF-2 to ...
14508666
Protective effect of a vegetable extract from Lupinus albus (LU 105) on human gingival elastic fibers degradation by human leukocyte elastase.
The aim of this study was to determine if a vegetable extract from seeds of Lupinus albus (LU 105) has the capacity to inhibit human leukocyte elastase and/or protect gingival elastic fibers against proteolytic degradation. LU105 was extracted from seeds of L albus and is freely soluble in water. In this study the ex-v...
14507995
Biosilica formation in diatoms: characterization of native silaffin-2 and its role in silica morphogenesis.
The biological formation of inorganic materials with complex form (biominerals) is a widespread phenomenon in nature, yet the molecular mechanisms underlying biomineral morphogenesis are not well understood. Among the most fascinating examples of biomineral structures are the intricately patterned, silicified cell wall...
14872233
A diffuse reflectance comparative study of benzil inclusion within microcrystalline cellulose and beta-cyclodextrin.
Diffuse reflectance and laser-induced techniques were used to study photochemical and photophysical processes of benzil adsorbed on two solid powdered supports, microcrystalline cellulose and [small beta]-cyclodextrin. In both substrates, a distribution of ground-state benzil conformers exists, largely dominated by ske...
14506277
Reduction of glycosphingolipid levels in lipid rafts affects the expression state and function of glycosylphosphatidylinositol-anchored proteins but does not impair signal transduction via the T cell receptor.
Lipid rafts are highly enriched in cholesterol and sphingolipids. In contrast to many reports that verify the importance of cholesterol among raft lipid components, studies that address the role of sphingolipids in raft organization and function are scarce. Here, we investigate the role of glycosphingolipids (GSLs) in ...
14532657
The isothiocyanate complex of triphenylborane forms an unusual coordination polymer with [K(18-crown-6)](+), both in the solid state and in solution.
The title salt, (1,4,7,10,13,16-hexaoxacyclooctadecane-kappa(6)O)[(isothiocyanato)triphenylborato-kappaS]potassium(I), [K(C(19)H(15)BNS)(C(12)H(24)O(6))] or [K(SCNBPh(3))(18-crown-6)], where 18-crown-6 is 1,4,7,10,13,16-hexaoxacyclooctadecane and [SCNBPh(3)](-) is the (isothiocyanato)triphenylborate anion, exhibits a s...
14504402
Exclusively targeting beta-secretase to lipid rafts by GPI-anchor addition up-regulates beta-site processing of the amyloid precursor protein.
beta-Secretase (BACE, Asp-2) is a transmembrane aspartic proteinase responsible for cleaving the amyloid precursor protein (APP) to generate the soluble ectodomain sAPPbeta and its C-terminal fragment CTFbeta. CTFbeta is subsequently cleaved by gamma-secretase to produce the neurotoxic/synaptotoxic amyloid-beta peptide...
14504266
Peroxisome division in the yeast Yarrowia lipolytica is regulated by a signal from inside the peroxisome.
We describe an unusual mechanism for organelle division. In the yeast Yarrowia lipolytica, only mature peroxisomes contain the complete set of matrix proteins. These mature peroxisomes assemble from several immature peroxisomal vesicles in a multistep pathway. The stepwise import of distinct subsets of matrix proteins ...
14502275
Assembling a lasing hybrid material with supramolecular polymers and nanocrystals.
The combination of bottom-up and top-down processes to organize nanophases in hybrid materials is a key strategy to create functional materials. We found that oxide and sulphide nanocrystals become spontaneously dispersed in organic media during the self-assembly of nanoribbon supramolecular polymers. These nanoribbon ...
14500900
Redefining cholesterol's role in the mechanism of the cholesterol-dependent cytolysins.
The cholesterol-dependent cytolysins (CDCs) constitute a large family of pore-forming toxins that function exclusively on cholesterol-containing membranes. A detailed analysis of the various stages in the cytolytic mechanism of three members of the CDC family revealed that significant depletion of cholesterol from the ...
14500786
NMR structure of the forkhead-associated domain from the Arabidopsis receptor kinase-associated protein phosphatase.
Forkhead-associated (FHA) domains are phosphoprotein-binding modules found in diverse signaling proteins that bind partners phosphorylated on threonine or serine. Kinase-associated protein phosphatase from Arabidopsis employs its FHA domain for negative regulation of receptor-like kinase signaling pathways, which are i...
13679513
Gangliosides that associate with lipid rafts mediate transport of cholera and related toxins from the plasma membrane to endoplasmic reticulm.
Cholera toxin (CT) travels from the plasma membrane of intestinal cells to the endoplasmic reticulum (ER) where a portion of the A-subunit, the A1 chain, crosses the membrane into the cytosol to cause disease. A related toxin, LTIIb, binds to intestinal cells but does not cause toxicity. Here, we show that the B-subuni...
13679520
Orientational order of the lamellipodial actin network as demonstrated in living motile cells.
Lamellipodia of crawling cells represent both the motor for cell advance and the primary building site for the actin cytoskeleton. The organization of actin in the lamellipodium reflects actin dynamics and is of critical importance for the mechanism of cell motility. In previous structural studies, the lamellipodial ac...
13680526
Mutations in the gamma-actin gene (ACTG1) are associated with dominant progressive deafness (DFNA20/26).
Age-related hearing loss (presbycusis) is a significant problem in the population. The genetic contribution to age-related hearing loss is estimated to be 40%-50%. Gene mutations that cause nonsyndromic progressive hearing loss with early onset may provide insight into the etiology of presbycusis. We have identified fo...
14532664
Ethyl N-phenyloxamate.
The oxamate group in the title compound, C(10)H(11)NO(3), is almost coplanar with the phenyl ring because of intramolecular hydrogen-bonding interactions, and the structure can be described as an anilide single bonded to an ethyl carboxylate group. The supramolecular structure is achieved through intermolecular hard N-...
14532650
Helical catena-poly[[tris(1H-benzimidazole-kappaN(3))cobalt(II)]-micro-maleato-kappa(3)O,O':O"].
The crystal structure of the title compound, [Co(C(4)H(2)O(4))(C(7)H(6)N(2))(3)](n), consists of polymeric chains of the Co(II) complex. Two maleate dianions and three benzimidazole ligands coordinate to the Co(II) atom with a distorted octahedral geometry. The maleate dianions bridge neighbouring Co(II) atoms via both...
14532649
A uranyl ion complex of N-methyl-p-tert-butyldihomoammoniocalix[4]arene with diaquadipyridinelithium as counter-ion.
The title complex, diaquadipyridinelithium (N-methyl-p-tert-butyldihomoammoniocalix[4]arene-kappa(4)O)dioxouranium(VI) tripyridine solvate monohydrate, [Li(C(5)H(5)N)(2)(H(2)O)(2)][UO(2)(C(46)H(58)NO(4))].3C(5)H(5)N.H(2)O, contains an 'internal' tetraphenoxide-coordinated uranyl complex of the macrocycle, in which the ...
13130097
Size, position and dynamic behavior of PML nuclear bodies following cell stress as a paradigm for supramolecular trafficking and assembly.
The promyelocytic leukemia (PML) protein has been implicated in many cellular pathways, but it is unclear whether the accumulation of PML and other proteins into PML nuclear bodies is a regulated or random process. In this paper we have used a variety of physiological stresses, including heat stress, Cd+2 exposure and ...
12975367
Compared with Acyl-CoA:cholesterol O-acyltransferase (ACAT) 1 and lecithin:cholesterol acyltransferase, ACAT2 displays the greatest capacity to differentiate cholesterol from sitosterol.
The capacity of acyl-CoA:cholesterol O-acyltransferase (ACAT) 2 to differentiate cholesterol from the plant sterol, sitosterol, was compared with that of the sterol esterifying enzymes, ACAT1 and lecithin:cholesterol acyltransferase (LCAT). Cholesterol-loaded microsomes from transfected cells containing either ACAT1 or...
12972419
Synthetic peptides in the form of dendrimers become resistant to protease activity.
In previous papers, we observed that dendrimers of peptide mimotopes of the nicotinic receptor ligand site are strong antidotes against the lethality of the nicotinic receptor ligand alpha-bungarotoxin. Although their in vitro activity is identical to that of dendrimers, the corresponding monomeric peptide mimotopes ar...
12969505
Coupling of importin beta binding peptide on plasmid DNA: transfection efficiency is increased by modification of lipoplex's physico-chemical properties.
<h4>Background</h4>Non-viral vectors for gene transfer are less immunogenic than viral vectors but also less efficient. Significant effort has focused on enhancing non-viral gene transfer efficiency by increasing nuclear import of plasmid DNA, particularly by coupling nuclear localization peptidic sequences to plasmid ...
12969891
Caveolin-1 regulates contractility in differentiated vascular smooth muscle.
Caveolin is a principal component of caveolar membranes. In the present study, we utilized a decoy peptide approach to define the degree of involvement of caveolin in PKC-dependent regulation of contractility of differentiated vascular smooth muscle. The primary isoform of caveolin in ferret aorta vascular smooth muscl...
12968082
Diversification of furanocoumarin-metabolizing cytochrome P450 monooxygenases in two papilionids: Specificity and substrate encounter rate.
Diversification of cytochrome P450 monooxygenases (P450s) is thought to result from antagonistic interactions between plants and their herbivorous enemies. However, little direct evidence demonstrates the relationship between selection by plant toxins and adaptive changes in herbivore P450s. Here we show that the furan...
13680065
Monolithic silica columns with chemically bonded beta-cyclodextrin as a stationary phase for enantiomer separations of chiral pharmaceuticals.
An enantioselective silica rod type chiral stationary phase (CSP) is presented; a novel combination of the well known enantiomer separation properties of beta-cyclodextrin and the unique properties concerning the flow behavior of silica monoliths. Two different synthesis routes are described, and it was found that the ...
14743280
Photoelectrochemical properties of supramolecular species containing porphyrin and ruthenium complexes on TiO(2) films.
Modification of wide band gap semiconductor surfaces by a new generation of supramolecular sensitizers, combining porphyrin and ruthenium-phenanthroline complexes leads to versatile molecular interfaces, allowing the exploitation of photoinduced charge transfer in dye sensitized photoelectrochemical cells. meso-Tetrapy...
12963821
Cholesterol-induced conformational change in SCAP enhanced by Insig proteins and mimicked by cationic amphiphiles.
Sterols mediate feedback inhibition of the sterol regulatory element-binding protein (SREBP) pathway by preventing movement of the SREBP cleavage-activating protein (SCAP)/SREBP complex from endoplasmic reticulum (ER) to Golgi, where proteolytic cleavage of SREBPs releases the transcription factor domain that activates...
12963816
Engineering asymmetric vesicles.
Vesicles are bilayers of lipid molecules enclosing a fixed volume of aqueous solution. Ubiquitous in cells, they can be produced in vitro to study the physical properties of biological membranes and for use in drug delivery and cosmetics. Biological membranes are, in fact, a fluid mosaic of lipids and other molecules; ...
14615813
Use of surface plasmon resonance for the measurement of low affinity binding interactions between HSP72 and measles virus nucleocapsid protein.
The 72 kDa heat shock protein (HSP72) is a molecular chaperone that binds native protein with low affinity. These interactions can alter function of the substrate, a property known as HSP-mediated activity control. In the present work, BIAcore instrumentation was used to monitor binding reactions between HSP72 and natu...
12960435
Intersectin regulates fission and internalization of caveolae in endothelial cells.
Intersectin, a multiple Eps15 homology and Src homology 3 (SH3) domain-containing protein, is a component of the endocytic machinery in neurons and nonneuronal cells. However, its role in endocytosis via caveolae in endothelial cells (ECs) is unclear. We demonstrate herein by coimmunoprecipitation, velocity sedimentati...
12960433
Glom is a novel mitochondrial DNA packaging protein in Physarum polycephalum and causes intense chromatin condensation without suppressing DNA functions.
Mitochondrial DNA (mtDNA) is packed into highly organized structures called mitochondrial nucleoids (mt-nucleoids). To understand the organization of mtDNA and the overall regulation of its genetic activity within the mt-nucleoids, we identified and characterized a novel mtDNA packaging protein, termed Glom (a protein ...
12960161
Crystal structure of the human natural killer (NK) cell activating receptor NKp46 reveals structural relationship to other leukocyte receptor complex immunoreceptors.
Natural cytotoxicity receptors (NCR) mediate lysis of a variety of tumor and virus-infected cells by natural killer (NK) cells. Upon engagement, NCR trigger the cytolytic activity and cytokine release of NK cells through association with ITAM-containing signaling molecules. To further understand the function of these r...
12955391
Electrospray ionization mass spectrometry of terrestrial humic substances and their size fractions.
Electrospray ionization mass spectrometry (ESI-MS) was used to evaluate the average molecular mass of terrestrial humic substances, such as humic (HA) and fulvic (FA) acids from a soil, and humic acid from a lignite (NDL). Their ESI mass spectra, by direct infusion, gave average molecular masses comparable to those pre...
12955174
Intermittent high permeability hemofiltration in septic patients with acute renal failure.
<h4>Objective</h4>High permeability hemofiltration (HP-HF) is a new renal replacement modality designed to facilitate the elimination of cytokines in sepsis. Clinical safety data on this new procedure is still lacking. This study investigates the effects of HP-HF on the protein and coagulation status as well as on card...
12954985
Diversity of core antigen epitopes of hepatitis B virus.
Core antigen (cAg), the viral capsid, is one of the three major clinical antigens of hepatitis B virus. cAg has been described as presenting either one or two conformational epitopes involving the "immunodominant loop." We have investigated cAg antigenicity by cryo-electron microscopy at approximately 11-A resolution o...
20569394
Large scale parallel analysis of gene expression during infection-related morphogenesis of Magnaporthe grisea.
SUMMARY The rice blast fungus Magnaporthe grisea causes one of the most destructive diseases of rice. To initiate the infection of host tissues, conidia elaborate germ tubes that differentiate specialized infection structures called appressoria. Microarrays composed of 3500 cDNAs of M. grisea were prepared for the iden...
19475321
Drug-delivery systems for local anesthetics: therapeutic applications.
<h4>Background and objectives</h4>Many researchers in the last four decades have been devoted to the development of drug-delivery systems. Since its first application in the pharmaceutical industry, many results have been obtained especially in the molecular manipulation of carriers and their interaction with encapsula...
16220928
Extraction of monodisperse palladium nanoparticles from dendrimer templates.
We describe a strategy for extracting nearly size-monodisperse, 1.7-nm-diameter Pd nanoparticles from within dendrimer hosts. The approach involves two steps. First, an aqueous solution of dendrimer-encapsulated Pd nanoparticles is prepared, followed by the addition of a toluene solution containing an n-alkanethiol. Wh...
16220922
Novel peptides bearing pyrene and coumarin units with or without beta-cyclodextrin in their side chains exhibit intramolecular fluorescence resonance energy transfer.
Novel peptides bearing the pyrene/coumarin FRET pair in their side chains have been designed and synthesized. Peptide 1 having endogenous beta-cyclodextrin (beta-CD) in the side chain exhibits FRET in aqueous solution, indicating that coumarin, being accommodated into the CD cavity, is separated from pyrene. Guest-indu...
14723158
Biological activity of bacterial lectins and their molecular complexes with heterocyclic bis-adducts.
A new convenient method for the preparation of heterocyclic bis-adducts: of imidazole, benzimidazole, uracile with 1,1,1-trifluoro-2-bromo-2-chloroethane is described. The reactions are catalysed by the 18-crown-6-complex. The critical toxicity and antitumour activity of saprophytic strains Bacillus genus (B. subtilis ...
12951366
Macrophage cholesterol efflux and the active domains of serum amyloid A 2.1.
Serum amyloid A 2.1 (SAA2.1) suppresses ACAT and stimulates cholesteryl ester hydrolase (CEH) activities in cholesterol-laden macrophages, and in the presence of a cholesterol transporter and an extracellular acceptor, there is a marked increase in the rate of cholesterol export in culture and in vivo. The stimulation ...
14674467
Atrazine sensor based on molecularly imprinted polymer-modified gold electrode.
Molecularly imprinted polymers (MIP) have been elucidated to work as artificial receptors. In our present study, a MIP was applied as a molecular recognition element to a chemical sensor. We have constructed an atrazine sensor based on a MIP layer selective for atrazine and its electrochemical reduction on gold electro...
14674453
Detection of CrO4(2-) using a hydrogel swelling microcantilever sensor.
Hydrogels containing various mounts of tetraalkylammonium salts were used to modify microcantilevers for measurements of the concentration of CrO4(2-) in aqueous solutions. These microcantilevers undergo bending deflection upon exposure to solutions containing various CrO4(2-) concentrations as a result of swelling or ...
14658256
[Pharmacologic prevention of SIRS (systemic inflammatory response syndrome) in severe thoracic injuries].
<h4>Introduction</h4>Frequency and severity of the blunt chest injuries are increasing. Rather high letality is caused by the injury and following systemic inflammatory response.<h4>Objective</h4>The aim of the study is to verify the efficacy of pharmacological blockade of the systemic inflammatory response syndrome (S...
15376946
Multilayer lactate oxidase shells on colloidal carriers as engines for nanosensors.
Self-assembly methods are being studied for construction of nanoscale chemical sensors employing coimmobilized enzymes and indicator dyes. This paper describes the assembly of the catalytic enzyme lactate oxidase in multilayer films on colloidal templates via layer-by-layer self-assembly, which is a step toward achievi...
15369174
Fast method development and rapid analysis using a screening approach for enantiomeric separations in capillary electrophoresis.
In order to speed up the trial-and-error process during enantioselective capillary electrophoresis methods development, a systemized approach is proposed to develop methods by applying several screening methods in the search for an initial separation. Screening methods combine high selectivity with broad applicability ...
14632083
Chiral on-chip separations of neurotransmitters.
The fast on-chip determination of a range of compounds of relevance in the study and treatment of neurological disorders is demonstrated. These include dopamine and its metabolites methoxytyramine, homovanillic acid, noradrenaline, adrenaline, normetanephrine, and metanephrine, its artificial precursors DOPA and tyrosi...
14604109
Complementary on-line preconcentration strategies for steroids by capillary electrophoresis.
Complementary on-line preconcentration strategies are needed when analyzing different classes of solutes in real samples by capillary electrophoresis (CE) with UV detection. The performance of three different on-line preconcentration (focusing) techniques under alkaline conditions was examined in terms of their selecti...
14604104
Modified field amplification sample injection for micellar electrokinetic chromatography of neutral compounds with amino-substituted cyclodextrin as carrier and 1-adamantanecarboxylate as displacer.
A modified field amplification sample injection method was proposed and evaluated by using positively mono charged cyclodextrin (CD) as carrier and 1-adamantanecarboxylate as displacer for on-capillary preconcentration of neutral compounds and improvement of the concentration limit of detection in micellar electrokinet...
14593917
[Thermotoga neopolitina gene cluster, participating in degradation of starch and maltodextrins: expression of aglB and aglA gene in Escherichia coli, properties of recombinant enzymes].
The aglB and aglA genes from the starch/maltodextrin utilization gene cluster of Thermotoga neapolitana were subcloned into pQE vectors for expression in Escherichia coli. The recombinant proteins AglB and AglA were purified to homogeneity and characterized. Both enzymes are hyperthermostable, the highest activity was ...
14592674
Behavioral effects and anatomic correlates after brain injury: a progesterone dose-response study.
Evidence suggests that progesterone enhances functional recovery in rats after medial frontal cortical contusions; however, a high dose of progesterone exacerbates tissue loss in a stroke model when administered chronically (7-10 days) prior to injury [Stroke 31 (2000) 1173)]. This study attempts to determine progester...
14582229
[Localization of crystallins in Muellerian cells in the grass frog retina].
Cell localization of 23 kDa- and 35 kDa-crystallins in the retina of adult common frogs Rana temporaria L. was studied using indirect immunofluorescence. Intense specific fluorescence of both crystallins was observed all over the retina, in both periphery and central area. It was localized in elongated radially oriente...
14579523
Novel bone-targeted Src tyrosine kinase inhibitor drug discovery.
Bone-targeted Src tyrosine kinase (STK) inhibitors have recently been developed for the treatment of osteoporosis and cancer-related bone diseases. The concept of bone targeting derives from bisphosphonates, and from the evolution of such molecules in terms of therapeutic efficacy for the treatment of bone disorders. I...
14575588
[Effective and stable in vitro expression of human coagulation factor VIII by retrovirus-based plasmid vector coupled with polyamidoamine dendrimer].
<h4>Objective</h4>To demonstrate the effectiveness of a retrovirus-based plasmid vector coupled with nanometer material-polyamidoamine (PAMAM) dendrimer in stable gene expression of FVIII in vitro and to study the cytotoxicity of PAMAM.<h4>Methods</h4>The retrovirus-based plasmid vector pLNC-FVIII BD was generated by c...
14575293
Continuous renal replacement therapy (CRRT) or intermittent hemodialysis (IHD)--what is the procedure of choice in critically ill patients?
Although at present there is no prospective randomized study which could show significantly better survival of patients on continuous procedures, the majority of intensivists advocate this technique of renal function replacement due to generally accepted opinion that it has less effect on circulation of already hemodyn...
14574628
Cholesterol modulates amyloid beta-peptide's membrane interactions.
The causal relationship between amyloid beta-peptide (Abeta) deposition and Alzheimer's disease (AD)-specific neuropathological lesions such as neurodegeneration and cortical atrophy is still not known. Mounting evidence points to alterations in cholesterol homeostasis occurring in AD brain that are probably linked to ...
14574627
Cholesterol, a modulator of membrane-associated Abeta-fibrillogenesis.
One of the major pathological features of Alzheimer's disease is the presence of extracellular amyloid plaques that are predominantly composed of the amyloid-beta peptide (Abeta). Characterisation of plaques demonstrated the predominance of two peptides differing at the carboxyl terminus by 2 hydrophobic amino acids, A...
14571982
Sequence analysis of cyclodextrin glycosyltransferase from the alkaliphilic Bacillus agaradhaerens.
The gene encoding an alkaline active cyclodextrin glycosyltransferase (CGTase) from the alkaliphilic B. agaradhaerens LS-3C was cloned and sequenced. It encodes a mature polypeptide of 679 amino acids with a molecular mass of 76,488 Da. The deduced amino acid sequence of the mature CGTase revealed 99 and 95% identity t...
14571979
Integrated immobilized cell reactor-adsorption system for beta-cyclodextrin production: a model study using PVA-cryogel entrapped Bacillus agaradhaerens cells.
Production of cyclodextrins (CDs) by immobilized cells of the alkaliphilic Bacillus agaradhaerens LS-3C with integrated product recovery was studied. The microorganism was entrapped in polyvinyl alcohol-cryogel beads and used as a convenient source of immobilized cyclodextrin glycosyltransferase (CGTase). On activation...
14570311
Potential use of cyclodextrins to enhance the solubility of YM466 in aqueous solution.
Various solubilizing agents for YM466, a new Factor Xa inhibitor, were investigated to begin designing the aqueous formulation for subcutaneous administration. The tentative target concentration was 5 mg/mL. First, three kinds of buffer solutions (glycine-HCl, citrate, and lactate) were examined for their solubilizing ...
14554088
Exposure to low infective doses of HCV induces cellular immune responses without consistently detectable viremia or seroconversion in chimpanzees.
In hepatitis C virus (HCV) infection, there is accumulating data suggesting the presence of cellular immune responses to HCV in exposed but seemingly uninfected populations. Some studies have suggested cross-reactive antigens rather than prior HCV exposure as the main reason for the immune responses. In this study we a...
14531461
Modified release bi-layered tablet of melatonin using beta-cyclodextrin.
A modified release bi-layered tablet of melatonin incorporating a fast release fraction consisting of melatonin-beta-cyclodextrin inclusion complex and a slow release fraction containing melatonin in HPMC K15M and Carbopol 971 P matrices was prepared. The formulation developed showed an initial burst followed by a near...
14531460
Rofecoxib-beta-cyclodextrin inclusion complex for solubility enhancement.
Complex formation of rofecoxib and beta-cyclodextrin in aqueous solution and in solid state and the possibility of improving the solubility and dissolution rate of rofecoxib via complexation with cyclodextrin were investigated. Phase solubility studies indicated the formation of an 1:1 complex in solution and the value...
14531458
Kinetics of degradation of diclofenac sodium in aqueous solution determined by a calorimetric method.
An isothermal heat conduction microcalorimeter has been used to study the stability of diclofenac sodium both alone and its inclusion complex with beta-cyclodextrin in aqueous solution. The rates of heat evolved during degradation of diclofenac sodium have been measured by a highly sensitive microcalorimetric technique...
14529926
Biliary tract complications following liver transplantation.
<h4>Introduction</h4>Biliary tract complications, which occur in 5.8% to 24.5% of adult liver transplant recipients, remain one of the most common problems following transplantation. The aim of this study was to evaluate these problems and analyze methods of treatment.<h4>Material and methods</h4>From 1989 to 2003, 36 ...
14529912
Liver transplantation across ABO blood groups in children.
Late results after ABOI LTx are inferior to ABO compatible organs. We report seven patients who received LTx across ABO group for emergency indications. The blood type combinations were: A to O in three, B to O in two, and B to A in two. Episodes of acute and chronic rejection, immunosuppression, and biochemical and fu...
14529025
Effects of DNA mismatches on binding affinity and kinetics of polymerase-DNA complexes as revealed by surface plasmon resonance biosensor.
In this study, surface plasmon resonance (SPR) biosensor techniques were used to obtain quantitative information on the kinetics of the DNA and polymerase I (Klenow fragment) interaction. DNA duplexes containing different base compositions at the binding site were immobilized on the SPR sensor surface via biotin-strept...
14529021
Water-soluble cyclodextrin polymers for enhanced relative recovery of hydrophobic analytes during microdialysis sampling.
Microdialysis relative recovery (RR) enhancement using different water-soluble, epichlorohydrin-based cyclodextrin polymers (CD-EPS) was studied in vitro for different analytes, amitryptiline, carbamazepine, hydroquinone, ibuprofen, and 4-nitrophenol. When compared to the native CDs (alpha, beta, and gamma) on a per mo...
14527144
Alkali metal ion complexes of functionalised calixarenes--competition between pendent arm and anion bonding to sodium.
Determination of the crystal structure of the acetonitrile inclusate of the complex formed between sodium trifluoromethanesulfonate (triflate, CF3SO3-) and the narrow-rim functionalised calix[4]arene, 5,11,17,23-tetra-tert-butyl-25,27-di(phenylmethoxy)-26,28-di(2'-methoxyethoxy)calix[4]arene, has shown, somewhat unexpe...
14523947
Destination 'lysosome': a target organelle for tumour cell killing?
Lysosomes and lysosome-related organelles constitute a system of acid compartments that interconnect the inside of the cell with the extracellular environment via endocytosis, phagocytosis and exocytosis. In recent decades it has been recognized that lysosomes are not just wastebaskets for disposal of unused cellular c...
14523946
The molecular basis of celiac disease.
Celiac disease is caused by inflammatory, gluten specific T cell responses in the small intestine. Invariably such responses are HLA-DQ2 or HLA-DQ8 restricted, providing an explanation for the strong association between celiac disease and these HLA-class II alleles. It is now clear that some native gluten sequences can...
14523945
Recombinant antibodies with MHC-restricted, peptide-specific, T-cell receptor-like specificity: new tools to study antigen presentation and TCR-peptide-MHC interactions.
The advent in recent years of the application of tetrameric arrays of class I peptide-MHC complexes now enables us to detect and study rare populations of antigen-specific CD8+ T cells. However, available methods cannot visualize or determine the number and distribution of these TCR ligands on individual cells or detec...
14523944
Targeting with scFv: immune modulation by complement receptor specific constructs.
The fate of a microbe in the host is determined by various molecules of the innate immune system, which recognize the microbe and enhance its interaction with antigen presenting cells. This 'natural targeting' phenomenon, however, does not function when antigens with limited immunogenicity enter the host. Peptide vacci...
14523943
Targeting dendritic cells for priming cellular immune responses.
The cardinal role of dendritic cells (DC) in priming adaptive immunity and in orchestrating immune responses against all classes of pathogens and also against tumors is well established. Their unique potential both to maintain self-tolerance and to initiate protective immune responses against foreign and/or dangerous s...
14523942
Drug targeting by macromolecules without recognition unit?
his review will summarize available information on the ability of macromolecular conjugates containing no specific recognition motifs to deliver anthracyclines (daunomycin, adriamycin) or methotrexate to target cells such as tumour cells or macrophages. Conjugates with natural (proteins, DNA, carbohydrates) and synthet...