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8270335 | Fatal chickenpox in a patient with nephrotic syndrome. | <h4>Background</h4>We report our experience with two patients with adult onset of chickenpox in the setting of longstanding steroid therapy for nephrotic syndrome. Ours is a 430-bed tertiary care teaching hospital, The Wellesley Hospital, Toronto, Ontario. Both patients presented as self-referrals to the emergency depa... |
7505682 | Design of a functional calcium channel protein: inferences about an ion channel-forming motif derived from the primary structure of voltage-gated calcium channels. | To identify sequence-specific motifs associated with the formation of an ionic pore, we systematically evaluated the channel-forming activity of synthetic peptides with sequence of predicted transmembrane segments of the voltage-gated calcium channel. The amino acid sequence of voltage-gated, dihydropyridine (DHP)-sens... |
8265343 | Translational repression by the human iron-regulatory factor (IRF) in Saccharomyces cerevisiae. | The regulation of the synthesis of ferritin and erythroid 5-aminolevulinate synthase in mammalian cells is mediated by the interaction of the iron regulatory factor (IRF) with a specific recognition site, the iron responsive element (IRE), in the 5' untranslated regions (UTRs) of the respective mRNAs. A new modular exp... |
8263169 | Detection of antibody to recombinant Norwalk virus antigen in specimens from outbreaks of gastroenteritis. | Norwalk virus and other small round-structured viruses are commonly associated with outbreaks of gastroenteritis. We used a recently described recombinant-expressed Norwalk virus (rNV) capsid protein in enzyme immunoassays to quantitatively measure immunoglobulin G (IgG) and IgA to Norwalk virus in serum pairs from pat... |
8255756 | The structure of the initiation complex at the replication origin, oriC, of Escherichia coli. | Two distinct regions in the replication origin, oriC, of Escherichia coli are separately distorted upon initiation complex formation by the initiator protein DnaA. The AT-rich region in the left part of oriC and the start site region in the right part of oriC. Chemical modification of single-stranded DNA was observed a... |
8254622 | Identification of potent, selective P2Y-purinoceptor agonists: structure-activity relationships for 2-thioether derivatives of adenosine 5'-triphosphate. | Study of P2-purinoceptor subtypes has been difficult due to the lack of potent and selective ligands. With the goal of developing high affinity P2-purinoceptor-selective agonist, we have synthesized a series of analogues of adenine nucleotides modified on the purine ring as chain-extended 2-thioethers or as N6-methyl-s... |
8254611 | Design and synthesis of an orally active macrocyclic neutral endopeptidase 24.11 inhibitor. | A potent macrocyclic inhibitor of neutral endopeptidase (NEP) 24.11 was designed using a computer model of the active site of thermolysin. This 10-membered ring lactam represents a general mimic for any hydrophobic dipeptide in which the two amino acid side chains bind to an enzyme in a contiguous orientation. The pare... |
8254341 | New platinum(II) complexes of beta-cyclodextrin diamine derivatives and their antitumor activity. | The new platinum(II) complexes of beta-cyclodextrin functionalized at the primary position with ethylenediamine or with propylenediamine were synthesized and characterized by mass spectrometry, electronic spectrophotometry, and multinuclear NMR spectroscopy. Platinum(II) complexation makes the cavity more asymmetric. T... |
7902704 | Beta 3-adrenergic receptors are responsible for the adrenergic inhibition of insulin-stimulated glucose transport in rat adipocytes. | The inhibition of insulin-stimulated glucose transport by isoprenaline, a mixed beta-adrenergic-receptor (AR) agonist, is well documented in rat adipocytes. Since it has been described that rat adipocytes possess not only beta 1- and beta 2- but also beta 3-ARs, the influence of various subtype-selective beta-AR agonis... |
8250844 | Expression of functional human retinol-binding protein in Escherichia coli using a secretion vector. | In order to express human serum retinol-binding protein (sRBP) in Escherichia coli in a form that is structurally indistinguishable from the native protein, we placed the coding sequence of the RBP cDNA next to that of the outer membrane protein A (OmpA) signal sequence in the secretion vector, pIN-III-OmpA1. However, ... |
8250838 | In vitro translation of androgen receptor cRNA results in an activated androgen receptor protein. | Translation of androgen receptor (AR) cRNA in a reticulocyte lysate and subsequent analysis of the translation products by SDS/PAGE showed a protein with an apparent molecular mass of 108 kDa. Scatchard-plot analysis revealed a single binding component with high affinity for R1881 (Kd = 0.3 nM). All AR molecules synthe... |
8250833 | Studies of the active site of m-calpain and the interaction with calpastatin. | Calpain autolyses in the presence of Ca2+. In the case of m-calpain (80 + 30 kDa) the first product is an 80 + 18 kDa species which has an intact large subunit and the C-terminal Ca(2+)-binding domain of the small subunit. It was possible to bind E64 into the active site of calpain in the presence of Ca2+ before cleava... |
7902387 | Photodegradation of protoporphyrin-dimethylester in solution and in organized environments. | The degradation of sensitizers used in photodynamic therapy (PDT) involves photooxidation either by molecular oxygen or by oxygen intermediates which leads to hydroxyaldehyde and formyl products or to ring opening. Our investigations focused on the spectroscopic changes which protoporphyrin-dimethylester (PP) exhibits ... |
8241254 | Membrane disorganization induced by perfringolysin O (theta-toxin) of Clostridium perfringens--effect of toxin binding and self-assembly on liposomes. | theta-Toxin (perfringolysin O) of Clostridium perfringens binds to membrane cholesterol with high (Kd approximately 10(-9) M) and low (Kd approximately 10(-7) M) affinities and causes membrane lysis of intact cells and liposomes. In order to understand the lytic process at the molecular level, the lysis of liposomes wa... |
8241120 | Fluorescence study of conformational flexibility of RNase S-peptide: distance-distribution, end-to-end diffusion, and anisotropy decays. | Frequency-domain fluorescence resonance energy transfer and anisotropy measurements were performed to characterize conformational dynamics of an analog of the RNase S-peptide (residues 1-20). Trp was used as a donor by replacing Phe 8, and a dansyl acceptor group was introduced at position 1 or 18. The distance-distrib... |
8239194 | The role of infection in outcome of Multiple Organ Failure. | It is widely assumed that infections are the principal cause and primary outcome determinant of the syndrome of Multiple Organ Failure (MOF) in critically ill patients. Infections are frequent in these patients, but the prevention and treatment of infections may not influence the course of MOF. This study tested the hy... |
8234324 | Refined 1.8 A structure of human aldose reductase complexed with the potent inhibitor zopolrestat. | As the action of aldose reductase (EC 1.1.1.21) is believed to be linked to the pathogenesis of diabetic complications affecting the nervous, renal, and visual systems, the development of therapeutic agents has attracted intense effort. We report the refined 1.8 A x-ray structure of the human holoenzyme complexed with ... |
8230227 | Dissecting the structure of a partially folded protein. Circular dichroism and nuclear magnetic resonance studies of peptides from ubiquitin. | The nature and interaction of structural elements in a partially ordered form of ubiquitin, the A-state, which is populated at low pH in 40 to 60% aqueous methanol, have been investigated. Two synthetic peptides have been studied under the same conditions: U(1-21), corresponding to the N-terminal beta-hairpin in the na... |
8230215 | Molecular recognition mediated by bound water. A mechanism for star activity of the restriction endonuclease EcoRI. | Many restriction endonucleases such as EcoRI lose some specificity for their recognition sequence under certain buffer conditions. The cause of this disruption of accurate protein-DNA recognition has never been explained. By cleaving DNA with EcoRI in the presence of several osmolytes, we show that the extent of this E... |
8227330 | Suramin interferes with interleukin-6 receptor binding in vitro and inhibits colon-26-mediated experimental cancer cachexia in vivo. | Neoplastic diseases are frequently associated with metabolic changes collectively known as cancer cachexia. The presence of cachexia complicates therapeutic intervention and is an important cause of death in cancer patients. At present there is no effective treatment for cachexia. Recently, the involvement of interleuk... |
8227139 | Isolation of the yeast nuclear pore complex. | Nuclear pore complexes (NPCs) have been isolated from the yeast Saccharomyces. Negative stain electron microscopy of the isolated NPCs and subsequent image reconstruction revealed the octagonal symmetry and many of the ultrastructural features characteristic of vertebrate NPCs. The overall dimensions of the yeast NPC, ... |
8227001 | Transcriptional regulation of puc operon expression in Rhodobacter sphaeroides. Involvement of an integration host factor-binding sequence. | The putative overlapping consensus sequences (-129 to -105) for binding of fumarate nitrate reductase regulator- and integration host factor (IHF)-like proteins to puc operon upstream DNA of Rhodobacter sphaeroides was protected from DNase I digestion by purified Escherichia coli IHF. The binding of E. coli IHF to the ... |
8226817 | Selection of targeted biological modifiers from a bacteriophage library of random peptides. The identification of novel calmodulin regulatory peptides. | The interaction of short amino acid sequences is the basis of molecular recognition and biological regulation in many cellular systems. Libraries of random peptides provide an approach to identify peptides that can be used to modulate, in a targeted fashion, the function of specific gene products. We have used a librar... |
7693658 | devRS, an autoregulated and essential genetic locus for fruiting body development in Myxococcus xanthus. | Two Tn5 lac insertions into the Myxococcus genome at sites omega 4414 and omega 4473, which are separated by 550 nucleotides, inactivate fruiting body development. Sporulation is decreased 100- to 10,000-fold. At least two genes, devR and devS, are transcribed in this region, probably as an operon. Expression of devR b... |
8226690 | Biosynthesis of the corrin macrocycle of coenzyme B12 in Pseudomonas denitrificans. | Studies with cell-free protein preparations from a series of recombinant strains of Pseudomonas denitrificans demonstrated that precorrin-3 is converted into a further trimethylated intermediate, named precorrin-3B, along the pathway to coenzyme B12. It was then shown that the part of the pathway from precorrin-3 (call... |
8226688 | Hemin uptake in Porphyromonas gingivalis: Omp26 is a hemin-binding surface protein. | A 26-kDa outer membrane protein (Omp26) has been proposed to play a role in hemin acquisition by Porphyromonas gingivalis (T. E. Bramanti and S. C. Holt, J. Bacteriol. 174:5827-5839, 1992). We studied [55Fe]hemin uptake in P. gingivalis grown under conditions of hemin starvation (Omp26 expressed on the outer membrane s... |
8226643 | The active form of the KorB protein encoded by the Streptomyces plasmid pIJ101 is a processed product that binds differentially to the two promoters it regulates. | The korB gene of Streptomyces lividans plasmid pIJ101 is known to encode an autoregulated protein that also represses transcription of a gene, kilB, implicated in pIJ101 transfer and in spreading of the plasmid along mycelia of the recipient. Earlier work has indicated that the primary gene product of korB is a 10-kDa ... |
8225865 | IGF-1 enhancement of FGF-induced lens fiber differentiation in rats of different ages. | <h4>Purpose</h4>Previously, using lens epithelial explants from neonatal rats, we showed that both insulin and IGF-1 synergistically enhance the effectiveness of FGF as an inducer of fiber differentiation. The authors aimed to determine whether IGF-1 enhances FGF-induced fiber differentiation in lens epithelial cells a... |
8223995 | Neural crest cell interaction with type VI collagen is mediated by multiple cooperative binding sites within triple-helix and globular domains. | Collagen type VI (Col VI) is a primary constituent of the extracellular matrix encountered by migrating avian neural crest cells in situ and is effective in promoting attachment and motility of these cells in vitro. In this study, we have explored the molecular mechanisms of neural crest-Col VI interaction by using qua... |
8223636 | Broad binding-site specificity and affinity properties of octamer 1 and brain octamer-binding proteins. | The ubiquitous Pit-1-Oct-1-Unc-1 (POU)-domain protein octamer 1 (Oct-1) has been observed to bind specifically to a number of degenerate and dissimilar sequences. We have used antibodies directed against a C-terminal Oct-1 peptide to immunoselect binding sequences for HeLa cell Oct-1 from random-sequence oligonucleotid... |
8223451 | The alpha-helical rod domain of human lamins A and C contains a chromatin binding site. | We examined regions of human lamins A and C involved in binding to surfaces of mitotic chromosomes. An Escherichia coli expression system was used to produce full-length lamin A and lamin C, and truncated lamins retaining the central alpha-helical rod domain (residues 34-388) but lacking various amounts of the amino-te... |
8223431 | FGF3 from Xenopus laevis. | Fibroblast growth factor 3 (FGF3) was first identified as the product of a cellular oncogene activated by mouse mammary tumour virus but its normal role appears to be in the developing embryo. To gain further insights into its function, we have isolated sequences encoding the FGF3 homologue in Xenopus laevis, XFGF3. CO... |
8218220 | Molecular recognition in cytochrome P-450: mechanism for the control of uncoupling reactions. | The pathway for utilization of pyridine nucleotide derived reducing equivalents in the cytochrome P-450 monooxygenase systems has three major branch points. The first is a partitioning between autoxidation of a ferrous, oxygenated heme adduct and input of the second reducing equivalent required for monooxygenase stoich... |
8413284 | Identification of C/EBP basic region residues involved in DNA sequence recognition and half-site spacing preference. | C/EBP and GCN4 are basic region-leucine zipper (bZIP) DNA-binding proteins that recognize the dyad-symmetric sequences ATTGCGCAAT and ATGAGTCAT, respectively. The sequence specificities of these and other bZIP proteins are determined by their alpha-helical basic regions, which are related at the primary sequence level.... |
8413280 | Transcription of alpha-specific genes in Saccharomyces cerevisiae: DNA sequence requirements for activity of the coregulator alpha 1. | Transcription activation of alpha-specific genes in Saccharomyces cerevisiae is regulated by two proteins, MCM1 and alpha 1, which bind to DNA sequences, called P'Q elements, found upstream of alpha-specific genes. Neither MCM1 nor alpha 1 alone binds efficiently to P'Q elements. Together, however, they bind cooperativ... |
8413258 | The intracisternal A-particle upstream element interacts with transcription factor YY1 to activate transcription: pleiotropic effects of YY1 on distinct DNA promoter elements. | Murine intracisternal A-particle long terminal repeats contain an intracisternal A-particle upstream enhancer (IUE) element that binds to a 65-kDa IUE binding protein (IUEB) present in both undifferentiated F9 embryonal carcinoma cells and differentiated parietal endoderm-like PYS-2 cells. This IUE element confers a Cp... |
7692082 | A conserved neutralizing epitope on gp41 of human immunodeficiency virus type 1. | Vaccination against human immunodeficiency virus type 1 (HIV-1) requires an immunogen which will elicit a protective immunity against viruses that show a high degree of genetic polymorphism. Therefore, the identification of neutralizing epitopes which are shared by many strains would be useful. In previous studies, we ... |
8105105 | CD13 (human aminopeptidase N) mediates human cytomegalovirus infection. | Human cytomegalovirus (HCMV) infects cells by a series of processes including attachment, penetration via fusion of the envelope with the plasma membrane, and transport of the viral DNA to the nucleus. The details of the early events of HCMV infection are poorly understood. We have recently reported that CD13, human am... |
8411342 | Identification of domains in brome mosaic virus RNA-1 and coat protein necessary for specific interaction and encapsidation. | Even though many single-stranded RNAs are present in the cytoplasm of infected cells, encapsidation by brome mosaic virus (BMV) coat protein is specific for BMV RNA. Although the highly conserved 3' region of each of the three BMV genomic RNAs is an attractive candidate for the site of recognition by the coat protein, ... |
33874589 | Plasmodesmata and the supracellular nature of plants. | In the classical formulation of Münch (1930), plasmodesmata are considered to form simple cytoplasmic bridges between neighbouring plant cells to create the symplasm. This concept has dominated, if not monopolized, the thinking of plant biologists and in particular plant physiologists over the last few decades. Recent ... |
24248723 | Species discrimination in five species of winter-flying geometrids (Lepidoptera) based on chirality of semiochemicals and flight season. | Enantiomer separation of (6Z,9Z)-cis-3,4-epoxynonadecadiene and (3Z,9Z)-cis-6,7-epoxynonadecadiene could be achieved using chiral high-resolution gas chromatography and a cyclodextrin-bond column. (3Z,9Z)-(6R,7S)-Epoxynonadecadiene was identified from ovipositor extracts ofColotois pen-Naria, while inErannis defoliaria... |
18965836 | Host-guest stabilized room temperature phosphorescence in beta-cyclodextrin/ bromoalcohol solutions from 2-naphthyl-oxy-acetic acid and 1-naphthyl-acetic acid. | Room temperature phosphorescence (RTP) from 2-naphthyl-oxy-acetic acid (NOA) and 1-naphthyl-acetic acid (NAA), with stabilization by use of beta-cyclodextrin (beta-CD) as a host system, has been examined. 2-Bromoethanol and 2,3-dibromopropanol have been evaluated as external heavy atom perturbers to enhance the rate of... |
17736822 | Nonlinear optical properties of proteins measured by hyper-rayleigh scattering in solution. | Hyper-Rayleigh scattering has been used to determine the nonlinear optical properties of a chromophore-containing protein in solution. Because the technique of hyper-Rayleigh scattering allows the measurement of hyperpolarizabilities in an isotropic solution without the application of an electric field, this method is ... |
8313186 | [Thromboxane and prostacyclin imbalance in the pathogenesis of early damage after severe burns]. | To define the pathogenesis of hemodynamical and hemorrheological changes as well as multiple organ failure (MOF) during early postburn stage, we determined the levels of thromboxane A2(TXA2) and prostacyclin (PGI2) and some other related variables in 57 patients, of which 14 were complicated by MOF. The results showed ... |
8305583 | Determination of cyclodextrins in serum by reversed-phase chromatography with pulsed amperometric detection and a membrane reactor. | A high-performance liquid chromatographic method has been developed for the determination of cyclodextrins (CDs) in serum. The method involves solid-phase extraction of CDs, separation on a C18 reversed-phase column using a mixture of water, tetrahydrofuran and methanol as an eluent, eluent pH modification with a catio... |
8298190 | How the transition frequencies of microtubule dynamic instability (nucleation, catastrophe, and rescue) regulate microtubule dynamics in interphase and mitosis: analysis using a Monte Carlo computer simulation. | Microtubules (MTs) in newt mitotic spindles grow faster than MTs in the interphase cytoplasmic microtubule complex (CMTC), yet spindle MTs do not have the long lengths or lifetimes of the CMTC microtubules. Because MTs undergo dynamic instability, it is likely that changes in the durations of growth or shortening are r... |
7507683 | Molecular basis of the exclusive low-temperature synthesis of an enzyme in E. coli: penicillin acylase. | The enzyme penicillin acylase is synthesized by Escherichia coli only at growth temperatures below 30 degrees C. The biochemical basis of this strict temperature-dependent formation of an enzyme was investigated. When the gene (pac) was under the control of the lacUV5 promoter it showed the same temperature-dependent e... |
8287136 | Separation of gangliosides using cyclodextrin in capillary zone electrophoresis. | Gangliosides are glycosphingolipids containing sialic acid. These glycolipids have been suggested to play important roles in biological processes such as cell growth, differentiation and malignant transformation. Based on these proposed biological functions, gangliosides can be used as diagnostic tools and therapeutics... |
8287044 | Characterization of lignoceroyl-CoA ligase activity in chicken liver microsomes. | Lignoceroyl-coenzyme A (CoA) ligase activity was detected in microsomal fractions from chicken liver in the presence of alpha-cyclodextrin as a solubilizing agent of lignoceric acid. Heptakis(2,6-di-O-methyl)-beta-cyclodextrin (dimethyl-beta-cyclodextrin) and hexakis(2,6-di-O-methyl)-alpha-cyclodextrin (dimethyl-alpha-... |
8283075 | The role of tumor necrosis factor-alpha in the aggravation of cerulein-induced pancreatitis in rats. | Severe acute pancreatitis is often complicated by intraperitoneal infection, resulting in multiple organ failure (MOF). It is known to elevate serum tumor necrosis factor (TNF-alpha) in patients with sepsis and/or MOF. In order to study the role of TNF-alpha in the aggravation of acute pancreatitis, we investigated TNF... |
7903968 | Self-assembly of symbionin, a chaperonin of intracellular symbiont. | Symbionin, a homologue of Escherichia coli GroEL, which functions as a molecular chaperone in the aphid endosymbiont, exists as a double-doughnut structure, consisting of two rings of seven 63-kDa subunits. Symbionin had a more labile oligomeric structure than GroEL and completely disassembled into monomeric (1-mer) co... |
8274641 | Structural heterogeneity of the Fe(2+)-N epsilon (HisF8) bond in various hemoglobin and myoglobin derivatives probed by the Raman-active iron histidine stretching mode. | We have examined the Fe(2+)-N epsilon (HisF8) complex in hemoglobin A (HbA) by measuring the band profile of its Raman-active nu Fe-His stretching mode at pH 6.4, 7.0, and 8.0 using the 441-nm line of a HeCd laser. A line shape analysis revealed that the band can be decomposed into five different sublines at omega 1 = ... |
8274636 | Support for the shape concept of lipid structure based on a headgroup volume approach. | Headgroup volumes of seven dioleoyl lipid species, calculated from covalent radii, are shown to correlate linearly (r = 0.95) with the ability of those lipids to alter the midpoint temperature of the lamellar to inverted hexagonal phase transition (L alpha-->HII) of a 95 mole fraction percent phosphatidylethanolamine m... |
8272419 | Salt and mesophase formation in aqueous suspensions of lauric acid. | The solubility and solution behavior of lauric acid (LA) and its 1:1 acid soap (potassium hydrogen dilaurate) were investigated at 32 degrees C over a pH range of 2.5-8.5 and at varying KCl concentrations to examine the self-association of this long-chain carboxylic acid under these conditions. LA's solubility in water... |
8271113 | Spectroscopic studies of tin ethyl etiopurpurin in homogeneous and heterogeneous systems. | Tin ethyl etiopurpurin is a promising second generation photosensitizer for photodynamic treatment of cancer. This compound is only poorly soluble in aqueous media and, therefore, needs a delivery system for administration to animals. Successful tumor eradication has previously been reported, following light exposure o... |
8259376 | Anti-platelet and anti-thrombotic effects of OP-41483.alpha-CD, a prostacyclin analogue, in experimental animals. | The effects of OP-41483.alpha-CD, 5(E)-6,9-deoxa-6,9 alpha-methylene-15-cyclopentyl-16,17,18,19,20-pentanor prostacyclin (PGI2).alpha-cyclodextrin clathrate, on platelet function and experimental thrombosis were studied. In human platelets, OP-41483 inhibited aggregation induced by adenosine diphosphate (ADP) or collag... |
7764261 | Purification and biochemical properties of an alkaline pullulanase from alkalophilic Bacillus sp. S-1. | A novel extracellular pullulanase (PUL-E, pullulan 6-glucanohydrolase, EC 3.2.1.41) has been purified from the alkalophilic Bacillus sp. S-1. The purified enzyme had a molecular mass of about 140 kDa on denaturated and natural conditions. The pI was 5.5. The pullulanase, when resolved by SDS-PAGE, was negative for Schi... |
8257128 | CGP 53437, an orally bioavailable inhibitor of human immunodeficiency virus type 1 protease with potent antiviral activity. | CGP 53437 is a peptidomimetic inhibitor of human immunodeficiency virus type 1 (HIV-1) protease containing a hydroxyethylene isostere. The compound inhibited recombinant HIV-1 protease with a Ki of 0.2 nM. The inhibition constant versus human cathepsin D and human cathepsin E was 4 nM. Human pepsin and gastricsin were ... |
8254493 | Oral pharmacokinetics of carbamazepine in dogs from commercial tablets and a cyclodextrin complex. | The extent of absorption of carbamazepine from a 2-hydroxypropyl-beta-cyclodextrin/carbamazepine complex was significantly greater and the rate of absorption was faster when compared with an immediate-release carbamazepine tablet in the dog. Six dogs were dosed orally in a two-way crossover study in which the tablet wa... |
8254492 | Improved bioavailability of para-boronophenylalanine by cyclodextrin complexation. | This study was undertaken to develop an oral dosage form for para-boronophenylalanine (BPA) plus cyclodextrin (CD) for use in the thermal neutron capture therapy for malignant melanoma. Powders of the BPA and CD complexes were obtained in a molar ratio of 1:2. X-ray diffraction of the BPA-CD complexes showed halo patte... |
8252531 | The conformation of the monomethyl ethers of methyl beta-lactoside in D2O and Me2SO-d6 solutions. | The solution conformations of all the possible monomethyl ethers of methyl beta-lactoside have been analysed using molecular mechanics and dynamics calculations and nuclear magnetic resonance data (variable temperature and NOE experiments). The overall shape of all the compounds studied is fairly similar and may be des... |
8252528 | Regioselective synthesis and characterization of naphthylethylcarbamoyl-beta-cyclodextrins. | Regioselective reactions of 1-(1-naphthyl)ethyl isocyanate (NEIC) with beta-cyclodextrin (beta-CD) were studied with and without NaH activation of beta-CD in N,N-dimethylformamide (DMF) and pyridine. All six possible monosubstituted CD products were separated and characterized by proton NMR. Primary substitution produc... |
8251935 | Effect of a single aspartate on helix stability at different positions in a neutral alanine-based peptide. | A single aspartate residue has been placed at various positions in individual peptides for which the alanine-based reference peptide is electrically neutral, and the helix contents of the peptides have been measured by circular dichroism. The dependence of peptide helix content on aspartate position has been used to de... |
8243999 | The Drosophila melanogaster suppressor of Hairy-wing zinc finger protein has minimal effects on gene expression in Saccharomyces cerevisiae. | Many mutations in Drosophila melanogaster are gypsy retrotransposon insertions. Gypsy binds the protein (SUHW) encoded by the suppressor of Hairy-wing [su(Hw)] gene, and SUHW alters expression of surrounding genes. When gypsy is between an enhancer and promoter, SUHW blocks activation of transcription by the enhancer. ... |
7916730 | Effects of uvsX, uvsY and DNA topoisomerase on the formation of tandem duplications of the rII gene in bacteriophage T4. | We have characterized tandem duplications in the rII regions of phage T4. The rII deletion r1589 blocks only the function of the rIIA cistron, although it extends into the B cistron. Another rII deletion, r1236, blocks the function of the rIIB cistron and overlaps r1589. When a cross is made between r1589 and r1236, tr... |
8240830 | The laminin family. | During the preceding year significant progress has been made in our understanding of laminin structure and expression. Highlights include the identification of new subunit chains and molecular isoforms as well as new information on tissue-specific gene expression, laminin self-assembly and interactions with other matri... |
7694569 | Matrix metalloproteinases cleave at two distinct sites on human cartilage link protein. | The actions of human recombinant stromelysins-1 and -2, collagenase, gelatinases A and B and matrilysin on neonatal human proteoglycan aggregates were examined. With the exception of gelatinase B, aggrecan was degraded extensively by most metalloproteinases studied, whereas link protein showed only limited proteolysis.... |
8240249 | Expression in Escherichia coli of the flavin and the haem domains of Hansenula anomala flavocytochrome b2 (flavodehydrogenase and b2 core) and characterization of the recombinant proteins. | The flavin and haem domains of Hansenula anomala flavocytochrome b2 have been independently expressed in Escherichia coli. The flavin domain activity, studied only in the total cellular extract, owing to its instability, has characteristics very similar to those of the flavin domain obtained by proteolysis. The haem do... |
8238942 | Analytical applications of catalytic properties of modified cyclodextrins. | This paper describes the evaluation of the catalytic properties of modified cyclodextrins for analytical applications. The beta-dimethylcyclodextrin was modified by adding one and two imidazolyl groups at carbon three positions. The modifications produced enhancements of catalytic activity for the hydrolysis of p-nitro... |
7901838 | Isolation and characterization of the binding sequences for the product of the Arabidopsis floral homeotic gene AGAMOUS. | The Arabidopsis floral homeotic gene AGAMOUS (AG) is required for normal flower development. The deduced AG protein contains a region which shares substantial sequence similarity with the DNA-binding domains of known transcription factors, SRF (human) and MCM1 (yeast). Therefore, it is likely that AG is also a DNA-bind... |
8233820 | Cpf1 protein induced bending of yeast centromere DNA element I. | The centromere complex is a multicomponent structure essential for faithful chromosome transmission. Here we show that the S. cerevisiae centromere protein Cpf1 bends centromere DNA element I (CDEI) with the bend angle ranging from 66 degrees to 71 degrees. CDEI DNA sequences that carry point mutations which lead to re... |
8228409 | [Angiographic evaluation of reconstructed spinal arteries in thoracic aortic aneurysm surgery]. | Revascularization of the spinal arteries with thoracic aortic aneurysm were performed on nineteen patients using partial extracorporeal bypass. They were 16 men and 3 women. Age range were from 33 to 70 years (mean 49.9 +/- 10.3 years). There were eleven patients of dissecting aneurysm (DeBakey type IIIb in eight patie... |
8224351 | The role of lipoproteins in the delivery of tumour-targeting photosensitizers. | 1. Serum lipoproteins play an important role in the in vivo transport of several porphyrinoid derivatives having a moderate or high degree of hydrophobicity. 2. There appears to exist a correlation between the extent of photosensitizer association with low-density lipoproteins (LDL) and the efficiency of tumour targeti... |
8223608 | Aggregation of pyrene-labeled microsomal glutathione S-transferase. Effect of concentration. | Microsomal glutathione S-transferase was labeled by the fluorescence probe N-(1-pyrenyl)maleimide which modified 1 mol thiol residue/mol protein. The enzyme activity increased about tenfold after the binding. The pyrene-labeled microsomal glutathione S-transferase exhibited two fluorescence bands which are typical of p... |
8223595 | Specific molecular interaction sites on factor VII involved in factor X activation. | Factor VII, a serine-protease zymogen, and tissue factor, the cellular receptor/coenzyme, are the protein components of the macromolecular complex which initiates the extrinsic pathway of the coagulation cascade. Previous studies were directed to the identification of functional sites on factor VII which mediate factor... |
7692962 | Cooperative self-assembly of SH2 domain fragments restores phosphopeptide binding. | Multifunctional proteins frequently can be subdivided into discrete functional domains. Selected cytoplasmic proteins involved in signal transduction contain catalytic domains in addition to protein binding modules termed Src homology (SH) domains; SH2 domains bind phosphotyrosyl peptide sequences. Even as isolated mod... |
8105482 | Mutant DnaK chaperones cause ribosome assembly defects in Escherichia coli. | To determine whether the biogenesis of ribosomes in Escherichia coli is the result of the self-assembly of their different constituents or involves the participation of additional factors, we have studied the influence of a chaperone, the product of the gene dnaK, on ribosome assembly in vivo. Using three thermosensiti... |
8415727 | Measurement of the g-tensor of the P700+. signal from deuterated cyanobacterial photosystem I particles. | We report high-field continuous wave EPR spectra of P700+. in preparations obtained from deuterated cyanobacteria (Synechococcus lividus). Measurements were performed with photosystem I (PS-I) preparations, whole cells from cyanobacteria grown in 2H2O, and photosystem II (PS-II) preparations, as well as with protonated... |
8415649 | Quaternary ligand binding to aromatic residues in the active-site gorge of acetylcholinesterase. | Binding sites of Torpedo acetylcholinesterase (EC 3.1.1.7) for quaternary ligands were investigated by x-ray crystallography and photoaffinity labeling. Crystal structures of complexes with ligands were determined at 2.8-A resolution. In a complex with edrophonium, and quaternary nitrogen of the ligand interacts with t... |
8415644 | RNase E activity is conferred by a single polypeptide: overexpression, purification, and properties of the ams/rne/hmp1 gene product. | Ribonuclease E, an enzyme that processes pre-5S rRNA from its precursor, is now believed to be the major endoribonuclease participating in mRNA turnover in Escherichia coli. The product of the ams/rne/hmp1 gene, which is required for RNase E activity, was overexpressed, purified to near homogeneity by electroelution fr... |
8410113 | The benefit of leucovorin-modulated fluorouracil as postoperative adjuvant therapy for primary colon cancer: results from National Surgical Adjuvant Breast and Bowel Project protocol C-03. | <h4>Purpose</h4>This study was designed to evaluate the efficacy of leucovorin-modulated fluorouracil (5-FU) as adjuvant therapy for patients with Dukes' stage B and C colon cancer.<h4>Patients and methods</h4>Data are presented from 1,081 patients with Dukes' stage B and C carcinoma of the colon entered into National ... |
8408660 | Conserved cytoplasmic tyrosine residues of the gamma subunit are required for a phagocytic signal mediated by Fc gamma RIIIA. | Fc receptors for immunoglobulins are found on many cells and are important in host defense. We transfected Fc gamma RIIIA, present on macrophages and natural killer (NK) cells, into COS-1 cells to study its role in phagocytosis and calcium mobilization in the absence of other Fc gamma receptors. Human Fc gamma RIIIA-al... |
7691828 | Genetic identification, sequence, and alternative splicing of the Caenorhabditis elegans alpha 2(IV) collagen gene. | The nematode Caenorhabditis elegans has two type IV collagen genes homologous to the mammalian alpha 1(IV) and alpha 2(IV) collagen genes. We demonstrate by transgenic rescue of mutant animals that the genetic locus encoding the C. elegans alpha 2(IV) collagen gene is let-2 on the X chromosome. The most severe effect o... |
7691812 | Amino acids lining the channel of the gamma-aminobutyric acid type A receptor identified by cysteine substitution. | The binding of gamma-aminobutyric acid (GABA) to gamma-aminobutyric acid type A (GABAA) receptors triggers the opening of an anion-selective channel. To identify amino acid residues that line the channel, we combined cysteine mutagenesis and covalent chemical modification. We mutated, one at a time, four consecutive re... |
8407954 | Ca(2+)-dependent and thapsigargin-inhibited phosphorylation of Na+,K(+)-ATPase catalytic domain following chimeric recombination with Ca(2+)-ATPase. | Two chimeric proteins comprising the Na,K-ATPase catalytic domain (large cytosolic loop) and the two flanking regions of the Ca-ATPase were obtained by transient or stable expression in mammalian cells transfected with recombinant DNA. In the first chimera (CpNC), a large portion (containing the nucleotide-binding site... |
8407828 | recA mutations that reduce the constitutive coprotease activity of the RecA1202(Prtc) protein: possible involvement of interfilament association in proteolytic and recombination activities. | Twenty-eight recA mutants, isolated after spontaneous mutagenesis generated by the combined action of RecA1202(Prtc) and UmuDC proteins, were characterized and sequenced. The mutations are intragenic suppressors of the recA1202 allele and were detected by the reduced coprotease activity of the gene product. Twenty dist... |
7691747 | Vitronectin binds to Pneumocystis carinii and mediates organism attachment to cultured lung epithelial cells. | Pneumocystis carinii attaches to alveolar epithelial cells during the development of pneumonia. Adhesive proteins found within the alveolar space have been proposed to mediate P. carinii adherence to lung cells. Vitronectin (Vn), a 75-kDa glycoprotein present in the lower respiratory tract, has substantial cell-adhesiv... |
8404855 | Molecular mechanisms of pattern formation by the BRE enhancer of the Ubx gene. | The core activity of the Ubx gene enhancer BRE (bx region enhancer) is encoded within a 500 bp module. bx DNA outside this active module increases the level of expression, expands the expression into ventro-lateral ectoderm and partially stabilizes the late expression pattern. The products of the gap genes hb and tll a... |
8402738 | Therapeutic potential of chimeric and murine anti-(epidermal growth factor receptor) antibodies in a metastasis model for human melanoma. | On many tumors, high numbers of epidermal growth factor (EGF) receptors provide a target for antibody-mediated tumor therapy. We evaluate here the therapeutic potential of a mouse/human chimeric anti-(EGF receptor) antibody and compare it to the parental murine antibody in a xenograft model for metastatic melanoma. Our... |
8399241 | Resonance Raman study of the interactions between cytochrome c variants and cytochrome c oxidase. | The structural changes in oxidized yeast iso-1-cytochrome c and fully oxidized bovine cytochrome c oxidase that are induced upon complex formation have been analyzed by resonance Raman spectroscopy. The main spectral changes could be ascribed to cytochrome c, which in the case of the wild-type protein are essentially t... |
8399200 | Refined 1.8-A structure reveals the mode of binding of beta-cyclodextrin to the maltodextrin binding protein. | The maltodextrin binding protein from Escherichia coli serves as the initial receptor for both the active transport of and chemotaxis toward a range of linear maltose sugars. The X-ray structures of both the maltose-bound and sugar-free forms of the protein have been previously described [Spurlino, J. C., Lu, G.-Y., & ... |
8399186 | Role of electrostatic interactions in the binding of fluorescein by anti-fluorescein antibody 4-4-20. | Anti-fluorescein antibodies are excellent model systems for studying the biochemical basis of molecular recognition because a prodigious amount of both physico-chemical and structural information is available for these antibodies. Furthermore, recombinant single-chain antibodies have been produced for several anti-fluo... |
7691143 | Acetylsalicylic acid (ASA) protects the prostaglandin-cAMP-system of human hypernephroma cells against irradiation-induced alterations. | There is abundant evidence that inhibitors of prostaglandin (PG) biosynthesis might increase the radioresponse of certain tumour cells. This study investigated specific PG binding sites, eicosanoid production as well as intracellular cAMP levels in cultured human hypernephroma cells derived from 11 patients upon nephre... |
8104228 | Leukocyte response integrin and integrin-associated protein act as a signal transduction unit in generation of a phagocyte respiratory burst. | The leukocyte response integrin (LRI) is a phagocyte integrin which recognizes the basement membrane protein entactin and the synthetic peptide Lys-Gly-Ala-Gly-Asp-Val (KGAGDV). The function of LRI is intimately associated with that of a distinct membrane protein, integrin-associated protein (IAP), as antibodies which ... |
8396688 | Characterization of the DNA binding properties of polyomavirus capsid protein. | The DNA binding properties of the polyomavirus structural proteins VP1, VP2, and VP3 were studied by Southwestern analysis. The major viral structural protein VP1 and host-contributed histone proteins of polyomavirus virions were shown to exhibit DNA binding activity, but the minor capsid proteins VP2 and VP3 failed to... |
8371358 | Amino acid changes in the fourth conserved region of human immunodeficiency virus type 2 strain HIV-2ROD envelope glycoprotein modulate fusion. | The fourth conserved region (C4) of human immunodeficiency virus type 1 (HIV-1) surface glycoprotein has been shown to participate in CD4 binding and to influence viral tropism (A. Cordonnier, L. Montagnier, and M. Emerman, Nature [London] 340:571-574, 1989). To define the role of the corresponding region of HIV-2, we ... |
8396669 | Chimeric hepatitis B virus core particles with parts or copies of the hepatitis C virus core protein. | Either parts or multiple copies of the core gene of hepatitis C virus (HCV) were fused to the 3' terminus of the hepatitis B virus (HBV) core gene with 34 codons removed. As many as four copies of HCV core protein (720 amino acids) were fused to the carboxy terminus of truncated HBV core protein (149 amino acids) witho... |
8396664 | Characterization of chimeric full-length molecular clones of Aleutian mink disease parvovirus (ADV): identification of a determinant governing replication of ADV in cell culture. | The ADV-G strain of Aleutian mink disease parvovirus (ADV) is nonpathogenic for mink but replicates permissively in cell culture, whereas the ADV-Utah 1 strain is highly pathogenic for mink but replicates poorly in cell culture. In order to relate these phenotypic differences to primary genomic features, we constructed... |
8371345 | The 1,629-nucleotide open reading frame located downstream of the Autographa californica nuclear polyhedrosis virus polyhedrin gene encodes a nucleocapsid-associated phosphoprotein. | A 78-kDa protein was produced in bacteria from a clone of the 1,629-nucleotide open reading frame located immediately downstream from the polyhedrin gene of Autographa californica nuclear polyhedrosis virus. The identity of this protein was confirmed by its reactivity with peptide antiserum and amino terminal peptide s... |
8396656 | The conserved N-terminal region of Sendai virus nucleocapsid protein NP is required for nucleocapsid assembly. | Sendai virus nucleocapsid protein NP synthesized in the absence of other viral components assembled into nucleocapsid-like particles. They were identical in density and morphology to authentic nucleocapsids but were smaller in size. The reduction in size was probably due to the fact that they contained RNA only 0.5 to ... |
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