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2484026 | Molecular basis for potentiation of bleomycin-mediated degradation of DNA by polyamines. Experimental and molecular mechanical studies. | The bleomycin-mediated degradation of DNA is stimulated (amplified) by certain DNA binding compounds, such as polyamines, that distort the double helix. Computer modelling studies suggest that putrescine (1), spermidine (2), and spermine (3) bind preferentially on the floor of the major groove of (dGdC)5.(dGdC)5. This ... |
2637042 | Effect of intercalative binding compared to external binding on Z/B equilibrium of poly d(GMe5C) using fluorescent oxazolopyridocarbazoles as probes. | Using the fluorimetric determination of the binding isotherms in combination with circular dichroism, we have investigated the effect of the binding of the intercalating chromophore oxazolopyridocarbazole (OPC) to poly d(GMe5C) on B/Z equilibrium, compared to the effect of the external binder OPC derivative pentyl-2-OP... |
2637041 | Binding of lanthanum and gadolinium ions to concanavalin A studied calorimetrically at 25 degrees C. | The interaction between Concanavalin A (ConA) and the lanthanide ions La3+ and Gd3+ has been studied calorimetrically at 25 degrees C. The measurements were carried out at a pH of 4.5, where the protein exists prevailingly as a dimer. Calorimetry allows the direct determination of the binding enthalpy and the evaluatio... |
2636714 | [Continuous arteriovenous hemofiltration and hemofiltration using dialysis. Presentation of clinical cases]. | The authors describe case reports in which the CAVH and the CAVDH was of paramount importance in improving hemodynamic parameters in ARDS and MOF and various cardiac failure. The technique was very simple and results good in intensive care. |
2636043 | Nuclear Overhauser effects and conformations of branched trisaccharide methyl beta-glycosides that contain a 2,3-disubstituted galactose residue. | On the basis of the n.O.e. data and theoretical calculations, it was found that less than 90% of one conformer was present in aqueous solution for each of a series of trisaccharide methyl beta-glycosides with a 2,3-disubstituted galactose residue. |
2636040 | Nuclear Overhauser effects and conformations of branched trisaccharide methyl beta-glycosides that contain a 3,4-disubstituted galactose residue. | N.O.e. data after pre-irradiation of the anomeric protons and the 3JC,H values associated with the glycosidic linkages for a series of methyl beta-glycosides of trisaccharides that contain 3,4-disubstituted galactose residues have been measured. On the basis of the experimental results and theoretical calculations, it ... |
2630014 | [Damage caused by endotoxin of the neural components of the organ of Corti]. | The endotoxin (lipopolysaccharides, LPS) of H. influenzae extracted with phenol-water method was injected into the perilymphatic compartment of guinea pig via the round window membrane. The CAP thresholds of the cochleas injected with LPS rose to 70.00 +/- 21.76 dB. The N1 latency at threshold prolonged until 2.63 +/- ... |
2576455 | Sustained release of buserelin acetate, a luteinizing hormone-releasing hormone agonist, from an injectable oily preparation utilizing ethylated beta-cyclodextrin. | The possible use of heptakis (2,6-di-O-ethyl)-beta-cyclodextrin (DE-beta-CyD) as a parenteral sustained-release carrier for buserelin acetate, a luteinizing hormone-releasing hormone superagonist, has been examined. The in-vitro release of buserelin from the oily suspension was significantly retarded by the complexatio... |
2622572 | [Extracorporeal support technics in the treatment of multisystem failure. Our experience]. | Mortality rate among patients with septic, oliguric, multiple organ failure is high. Conventional hemodialysis has often detrimental effects on critically ill patients. Continuous arteriovenous hemofiltration (CAVH), continuous arteriovenous hemodialysis (CAVH/D) and continuous arteriovenous hemodialysis associated wit... |
2695063 | A transient-kinetic study of the nitrogenase of Klebsiella pneumoniae by stopped-flow calorimetry. Comparison with the myosin ATPase. | The pre-steady-state kinetics of MgATP hydrolysis by nitrogenase from Klebsiella pneumoniae were studied by stopped-flow calorimetry at 6 degrees C and at pH 7.0. An endothermic reaction (delta Hobs. = +36 kJ.mol of ATP-1; kobs. = 9.4 s-1) in which 0.5 proton.mol of ATP-1 was released, has been assigned to the on-enzym... |
2515794 | Reactivation of peptidoglycan synthesis in ether-permeabilized Escherichia coli after inhibition by beta-lactam antibiotics. | The recovery of peptidoglycan-synthesizing activity after inhibition by beta-lactam antibiotics was investigated in ether-permeabilized cells of Escherichia coli B. Such cells synthesize sodium dodecyl sulfate-insoluble peptidoglycan when provided with UDP-linked precursors and Mg2+. The ability of beta-lactam antibiot... |
2619273 | Oral and parenteral therapy with saperconazole (R 66905) of invasive aspergillosis in normal and immunocompromised animals. | Saperconazole (R 66905) is a broad-spectrum antifungal triazole with potent in vitro activity against Aspergillus spp. A total of 279 strains were tested in brain heart infusion broth. Development of the Aspergillus spp. was completely inhibited at 0.1 and 1 microgram of saperconazole per ml for 80.3 and 99.6% of the s... |
2613791 | Preparative isolation of glycoproteins from plasma membranes of different rat organs. | By a combination of high-performance affinity chromatographic (HPAC) methods, several membrane proteins from liver, Morris hepatoma and kidney were isolated. The use of a tandem system, consisting of a concanavalin A (ConA) and a wheat germ agglutinin (WGA) high-performance liquid chromatographic (HPLC) column, as a fi... |
2613787 | Displacement chromatography on cyclodextrin-silicas. II. Separation of cis-trans isomers in the reversed-phase mode on alpha-cyclodextrin-silica. | The feasibility of preparative separations of cis-trans isomers by displacement chromatography on analytical-scale alpha-cyclodextrin-silica columns operated in the reversed-phase mode is demonstrated by using the isomers of 3-hexen-1-ol as model substrates and n-alkanols as displacers. The importance of matching the s... |
2613786 | Displacement chromatography on cyclodextrin-silicas. I. Separation of positional and geometrical isomers in the reversed-phase mode. | The retention behaviour of several charged and uncharged solutes on beta-cyclodextrin-silica was studied as a function of the methanol concentration, ionic strength and pH of the eluent in order to develop efficient displacement chromatographic separations for positional and geometric isomers. These retention curves we... |
2515117 | Synthesis and secretion of hepatitis B middle surface antigen by the methylotrophic yeast Hansenula polymorpha. | The methylotrophic yeast, Hansenula polymorpha, has been developed as a host system for the synthesis of heterologous proteins. The middle surface antigen of hepatitis B virus (preS2-HBsAg) has been synthesized under the control of a methanol-regulated promoter derived from the methanol oxidase-encoding gene. The synth... |
2612895 | Analysis of the role of tra-1 in germline sex determination in the nematode Caenorhabditis elegans. | In wild-type Caenorhabditis elegans there are two sexes, self-fertilizing hermaphrodites (XX) and males (XO). To investigate the role of tra-1 in controlling sex determination in germline tissue, we have examined germline phenotypes of nine tra-1 loss-of-function (lf) mutations. Previous work has shown that tra-1 is ne... |
2515108 | DNA sequence analysis of artificially evolved ebg enzyme and ebg repressor genes. | The ebg system has been used as a model to study the artificial selection of new catalytic functions of enzymes and of inducer specificities of repressors. A series of mutant enzymes with altered catalytic specificities were previously characterized biochemically as were the changes in inducer specificities of mutant, ... |
2611262 | High-resolution differential scanning calorimetric study of myosin, functional domains, and supramolecular structures. | High-resolution differential scanning calorimetry (DSC) has been employed to study the thermal stability of myosin, its major constitutive fragments (S-1, light chains, and rod), and also reconstituted thick filaments. The thermal denaturation of soluble myosin was complex and was characterized by a multistep endotherm... |
2558581 | Receptors for extracellular matrix components. | The extracellular matrix determines the shape and function of multicellular organisms and permits orderly repair after injury. Although the inherent self-assembly properties of many extracellular matrix components such as collagen and elastin foster their deposition and supramolecular organization, cells ultimately dic... |
2608028 | An inhibitory effect of RGD peptide on protein-priming reaction of bacteriophages phi 29 and M2. | The amino acid sequence, arginine-glycine-aspartic acid (RGD), found in some cell adhesive proteins, is a recognition signal for the receptor protein. It is interesting that we have found the RGD sequence in terminal protein (TP) of bacteriophages phi 29 and M2 near an amino acid, the serine residue at 232, covalently ... |
2481315 | NMR study of the possible interaction in solution of angiotensin II with a peptide encoded by angiotensin II complementary RNA. | The potential binding of angiotensin II (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe) (AII) to a peptide encoded by its complementary RNA (Lys-Gly-Val-Asp-Val-Tyr-Ala-Val) (IIA) has been studied by monitoring the 1H NMR spectrum of IIA in aqueous phosphate or Tris.HCl buffer (2H2O) as it is titrated with AII. For molar ratios of A... |
2513570 | A humanized antibody that binds to the interleukin 2 receptor. | The anti-Tac monoclonal antibody is known to bind to the p55 chain of the human interleukin 2 receptor and to inhibit proliferation of T cells by blocking interleukin 2 binding. However, use of anti-Tac as an immunosuppressant drug would be impaired by the human immune response against this murine antibody. We have the... |
2480964 | Selective immunoreactivities of kidney basement membranes to monoclonal antibodies against laminin: localization of the end of the long arm and the short arms to discrete microdomains. | To examine the ultrastructural distribution of laminin within kidney basement membranes, we prepared rat anti-mouse laminin mAbs to use in immunolocalization experiments. Epitope domains for these mAbs were established by immunoprecipitation, immunoblotting, affinity chromatography, and rotary shadow EM. One mAb bound ... |
2689442 | Expression of functional chicken oviduct progesterone receptors in yeast (Saccharomyces cerevisiae). | The cDNAs encoding full-length chicken oviduct progesterone receptor B (PRB) and a truncated receptor (C1C2) lacking the amino-terminal domain were expressed in yeast (Saccharomyces cerevisiae) using a ubiquitin fusion system. The expression of the fusion protein is under the control of a copper-responsive yeast metall... |
2532131 | Effect of ADP on the rate of acetyl phosphate hydrolysis by the Ca2+-ATPase of sarcoplasmic reticulum. | Hydrolysis of acetyl phosphate is inhibited by high concentrations of Pi and MgCl2, probably due to an increase in the steady-state level of phosphoenzyme formed from Pi in the medium. A dual effect of ADP during steady-state hydrolysis of acetyl phosphate was observed. ADP inhibited hydrolysis in the presence of 5 mM ... |
2689173 | Supramolecular structure of lipopolysaccharide and free lipid A under physiological conditions as determined by synchrotron small-angle X-ray diffraction. | Lipopolysaccharides, the major amphiphilic components of the outer leaflet of the outer membrane of Gram-negative bacteria, may assume various three-dimensional supramolecular structures depending on molecular properties (e.g. chemical structure) and on ambient conditions (e.g. temperature, concentration of divalent ca... |
2598927 | Differential effects of alpha-, beta- and gamma-cyclodextrins on human erythrocytes. | Alpha-, beta- and gamma-cyclodextrins are cyclic hexamers, heptamers, and octamers of glucose, respectively, and thus are hydrophilic; nevertheless, they have the ability to solubilize lipids through the formation of molecular inclusion complexes. The volume of lipophilic space involved in the solubilization process in... |
2512858 | A discrete repeated sequence defines a tubulin binding domain on microtubule-associated protein tau. | The protein domain responsible for the interaction of tau with tubulin has been identified. Biophysical studies indicated that the synthetic peptide Val187-Gly204 (VRSKIG-STENLKHQPGGG) from the repetitive sequence on tau binds to two sites on the tubulin heterodimer and to one site on each of the microtubule-associated... |
2556636 | Protein phosphorylation and regulation of adaptive responses in bacteria. | Bacteria continuously adapt to changes in their environment. Responses are largely controlled by signal transduction systems that contain two central enzymatic components, a protein kinase that uses adenosine triphosphate to phosphorylate itself at a histidine residue and a response regulator that accepts phosphoryl gr... |
2687331 | Mechanism of therapeutic effect of high-dose intravenous immunoglobulin. Attenuation of acute, complement-dependent immune damage in a guinea pig model. | Studies were performed in in vitro and in vivo models to assess the effect of intravenous immunoglobulin (IVIG) on the development of acute complement-mediated tissue damage. IVIG significantly increased the duration of survival and frequently prevented the death of guinea pigs injected with anti-Forssman antiserum to ... |
2687288 | Partial deduced sequence of the 110-kD-calmodulin complex of the avian intestinal microvillus shows that this mechanoenzyme is a member of the myosin I family. | The actin bundle within each microvillus of the intestinal brush border is laterally tethered to the membrane by bridges composed of the protein complex, 110-kD-calmodulin. Previous studies have shown that avian 110-kD-calmodulin shares many properties with myosins including mechanochemical activity. In the present stu... |
2556263 | 'SPKK' motifs prefer to bind to DNA at A/T-rich sites. | The termini of histone H1 and sea urchin spermatogenous H1 and H2B, which are essential for correct chromatin condensation, often contain repeats of the sequence SPK(R)K(R). A special type of beta-turn structural motif has been proposed for this sequence, and it has been shown that a segment of the sea urchin sperm H1 ... |
2556261 | Complex formation of human papillomavirus E7 proteins with the retinoblastoma tumor suppressor gene product. | The E7 proteins encoded by the human papillomaviruses (HPVs) associated with anogenital lesions share significant amino acid sequence homology. The E7 proteins of these different HPVs were assessed for their ability to form complexes with the retinoblastoma tumor suppressor gene product (p105-RB). Similar to the E7 pro... |
2531283 | Multiple splicing factors are released from endogenous complexes during in vitro pre-mRNA splicing. | Pre-mRNA splicing occurs in a macromolecular complex called the spliceosome. Efforts to isolate spliceosomes from in vitro splicing reactions have been hampered by the presence of endogenous complexes that copurify with de novo spliceosomes formed on added pre-mRNA. We have found that removal of these large complexes f... |
2555632 | Neutrophil function and lipid peroxidation in a rat model of multiple organ failure. | Multiple organ failure (MOF) was induced by sterile intraperitoneal inoculation of zymosan in the rat. This results in a typical triphasic illness with maximal clinical signs at Days 2 and 14. In this study, granulocyte superoxide production (unstimulated and phorbol myristic acid stimulated) was studied as well as lip... |
2479774 | Inhibition of human immunodeficiency virus type 1 RNase H by sulfated polyanions. | The reverse transcriptase (RT) activity of human immunodeficiency virus type 1 and other retroviruses is closely associated with a hybrid-degrading RNase H activity which is essential for retroviral replication. We have analyzed the effect of sulfated polysaccharides on human immunodeficiency virus type 1 recombinant R... |
2585609 | Transcriptional analysis of minute virus of mice P4 promoter mutants. | A series of 5' deletion, internal deletion, and linker-scanning mutants of the minute virus of mice P4 promoter were constructed and analyzed for transcriptional activity in nuclear extracts of mouse A92L fibroblasts. A GC box and a TATA box essential for in vitro transcription from the P4 promoter were localized betwe... |
2585607 | Evidence for specificity in the encapsidation of Sindbis virus RNAs. | We investigated the interaction of the capsid protein of Sindbis virus with Sindbis viral RNAs and defined a region of the genome that is required for binding in vitro and for packaging in vivo. The binding studies were performed with purified capsid protein immobilized on nitrocellulose and 32P-labeled RNAs transcribe... |
2479703 | Mapping of the Epstein-Barr virus and C3dg binding sites to a common domain on complement receptor type 2. | Complement receptor type 2 (CR2;CD21), a member of the superfamily of proteins containing short consensus repeats (SCRs), is the B cell receptor for both the gp350/220 envelope protein of Epstein-Barr virus (EBV), and for the C3dg protein of complement. By analysis of CR2 deletion mutants and chimeras formed with CR1 (... |
2555395 | Tumor necrosis factor-alpha enhances interferon-gamma-mediated class II antigen expression on astrocytes. | Astrocytes can function as antigen-presenting cells (APC) upon expression of class II antigens, which are induced by interferon-gamma (IFN-gamma). Tumor necrosis factor-alpha (TNF-alpha) can act synergistically with IFN-gamma with respect to class II expression on a variety of cells. As brain cells themselves can secre... |
2479549 | Regulated expression of Mg2+ binding epitope on leukocyte integrin alpha subunits. | The leukocyte integrins LFA-1, CR3 and p150,95 are a family of heterodimeric receptors that mediate divalent cation-dependent cellular adhesion reactions. In this study we describe a novel antibody-defined epitope present on the leukocyte integrin alpha subunits indicating that the antibody recognizes a structural feat... |
2555169 | Deletion of the gene for subunit III leads to defective assembly of bacterial cytochrome oxidase. | COIII is one of the major subunits in the mitochondrial and a bacterial cytochrome c oxidase, cytochrome aa3. It does not contain any of the enzyme's redox-active metal centres and can be removed from the enzyme without major changes in its established functions. We have deleted the COIII gene from Paracoccus denitrifi... |
2509368 | Degradation of basement membranes by Pseudomonas aeruginosa elastase. | Pseudomonas aeruginosa virulence has been attributed in part to extracellular proteinases. We found that one of these proteinases, elastase, extensively degrades intact basement membranes from bovine anterior-lens capsules, bovine glomeruli, and bovine lung, producing about 9, 14, and 9 fragments, respectively, with Mr... |
2637752 | Diffusion of ketoprofen from coprecipitates through a non porous lipidic membrane. | The effect of inclusion with beta-cyclodextrin or hydroxypropyl beta-cyclodextrin on the diffusion kinetics of Ketoprofen through a non porous lipidic membrane was analyzed starting from different dermal bases: a Carbopol gel, o/w emulsion and a fatty ointment. A constant diffusive gradient was achieved with the includ... |
2484014 | Binding of basic pancreatic trypsin inhibitor and related isoinhibitors to leukocytic elastase. Determination of thermodynamic parameters. | The effect of temperature, ionic strength and solvation power of mono- and divalent cations on the interaction of BPTI-like inhibitors with human leukocytic elastase has been determined. The binding process is characterized by a non-linear dependence of the equilibrium association constant on 1/T indicating a thermal t... |
2636902 | Association of anthracyclines and synthetic hexanucleotides. Structural factors influencing sequence specificity. | The equilibrium and kinetic aspects of the interaction between four anthracyclines and two synthetic self-complementary hexanucleotides was investigated by fluorescence detection. Two of the studied anthracyclines are widely used antitumor drugs: doxorubicin (1, formerly adriamycin) and daunorubicin (2, formerly daunom... |
2561530 | Binding characteristics of a series of dimeric tripeptide enkephalins for delta opiate receptors in rat brain and NG108-15 cells. | The N-terminal tripeptide enkephalin analogue, Tyr-D-Ala-Gly, was dimerized at the C-terminus systematically with a series of alpha,omega-diaminoalkanes, NH2-(CH2)n-NH2 (n = 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, and 22). The binding affinities of dimers for delta opiate receptors in rat brain were evaluated and compared ... |
2636901 | A heme- and metal-binding hexapeptide from the sequence of rabbit plasma histidine-rich glycoprotein. | Rabbit histidine-rich glycoprotein (HRG) binds low-spin heme and metals tightly at several sites that contain histidine. As part of an on-going effort to define and locate the binding sites for these and the other ligands of HRG, the sequence: NH2-Gly-His-Phe-Pro-Phe-His-Trp-... was found in a 16 kDa heme-binding pepti... |
2561529 | Model-building of Fnr and FixK DNA-binding domains suggests a basis for specific DNA recognition. | The DNA-binding C-terminal domains of the regulatory proteins Fnr from Escherichia coli and FixK from Rhizobium meliloti have been modelled on the basis of their homologies to the CAP protein from E. coli. Residues Glu181, Thr182 and Arg185 of CAP, which are exposed residues of the DNA-recognition helix alpha F, are co... |
2636900 | Conformational analysis of blood group A-active glycosphingolipids using HSEA-calculations. The possible significance of the core oligosaccharide chain for the presentation and recognition of the A-determinant. | Conformational analysis of four different A-active glycosphingolipids, A types 1-4, was carried out using HSEA-calculations with the GESA-program. In their minimum energy conformations the oligosaccharide chains are more or less curved; in particular the type 3 and 4 have a strongly bent shape. When the carbohydrate st... |
2533650 | Genotoxic potential of crown ethers in Salmonella typhimurium. | Macrocyclic polyethers (crown ethers) are a family of compounds which possess the ability to transport ionic species across natural and artificial membranes. Because of this characteristic, they have wide applications in industry and are being investigated for their potential as pharmacologic agents. However, these com... |
2559750 | A novel method for the purification of HIV-1 p24 protein from hybrid Ty virus-like particles (Ty-VLPs). | The self-assembly properties of a protein encoded by the yeast retrotransposon Ty can be exploited to produce large amounts of recombinant, particulate fusion proteins as hybrid Ty virus-like particles (Ty-VLPs). This system has now been adapted to allow the release of the additional protein by incorporation of a prote... |
2481821 | Immunological analysis of porin polymorphism in Escherichia coli B and K-12. | Two sets of monoclonal antibodies (MoF type I and MoF type II) directed against the OmpF protein were used to analyze the immunological reactivity of the major outer membrane porins of E. coli B and K-12. All these antibodies present a specificity to the native OmpF protein. In addition, among the type II antibodies, M... |
2605302 | Calculations of scattered light from rigid polymers by Shifrin and Rayleigh-Debye approximations. | We show that the commonly used Rayleigh-Debye method for calculating light scattering can lead to significant errors when used for describing scattering from dilute solutions of long rigid polymers, errors that can be overcome by use of the easily applied Shifrin approximation. In order to show the extent of the discre... |
2557933 | Polymorphism in the assembly of polyomavirus capsid protein VP1. | Polyomavirus major capsid protein VP1, purified after expression of the recombinant gene in Escherichia coli, forms stable pentamers in low-ionic strength, neutral, or alkaline solutions. Electron microscopy showed that the pentamers, which correspond to viral capsomeres, can be self-assembled into a variety of polymor... |
2600731 | Development of a non-surfactant formulation for alfaxalone through the use of chemically-modified cyclodextrins. | The poor water solubility of alfaxalone (less than 5 micrograms/mL), a useful steroid anesthetic agent, was dramatically increased via complexation with a series of four cyclodextrins. The most effective agent was 2-hydroxypropyl-beta-cyclodextrin (2HPCD) which solubilized alfaxalone in a linear manner as a function of... |
2583108 | The refined 1.9 A crystal structure of human alpha-thrombin: interaction with D-Phe-Pro-Arg chloromethylketone and significance of the Tyr-Pro-Pro-Trp insertion segment. | A stoichiometric complex formed between human alpha-thrombin and D-Phe-Pro-Arg chloromethylketone was crystallized in an orthorhombic crystal form. Orientation and position of a starting model derived from homologous modelling were determined by Patterson search methods. The thrombin model was completed in a cyclic mod... |
2817899 | Enhancement of chlorophyll a fluorescence yield, low-temperature F685/F730 fluorescence emission ratio, and electron transport rate by ether phospholipids (platelet activating factor and analogs) in isolated chloroplasts. | Acetyl glyceryl ether phosphorylcholine (1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine; or platelet activating factor (PAF)), when incubated with chloroplasts or subchloroplast fractions derived from stroma or grana lamellae, induces a drastic increase in the low-temperature fluorescence emission ratio F685/F730 (... |
2530919 | Electrochemical method for measuring C-reactive protein using crown ether--phosphate ester ionophores. | A new electrochemical method for measurement of C-reactive protein (CRP) is presented. We have synthesized new crown ether-phosphate ester ionophores having high affinity for CRP. A study using proton nuclear magnetic resonance shows CRP binding to the ionophores in stoichiometric amounts. The incorporation of these cr... |
2554317 | AbrB, a regulator of gene expression in Bacillus, interacts with the transcription initiation regions of a sporulation gene and an antibiotic biosynthesis gene. | The abrB gene of Bacillus subtilis is believed to encode a repressor that controls the expression of genes involved in starvation-induced processes such as sporulation and the production of antibiotics and degradative enzymes. Two such genes, spoVG, a sporulation gene of B. subtilis, and tycA, which encodes tyrocidine ... |
2808529 | The microtubule-binding fragment of microtubule-associated protein-2: location of the protease-accessible site and identification of an assembly-promoting peptide. | Thrombin cleavage of bovine brain microtubule-associated protein (MAP-2) yields two stable limit polypeptide fragments (28,000 and 240,000 Mr). The smaller cleavage product contains the microtubule-binding domain and is derived from the carboxyl terminus of MAP-2 while the 240,000 Mr fragment is derived from the amino ... |
2681228 | Biotin-tubulin incorporates into kinetochore fiber microtubules during early but not late anaphase. | The dynamic behavior of kinetochore fiber microtubules has been examined in PtK1 cells during anaphase of mitosis. Cells in anaphase were injected with biotin-tubulin and, at various intervals after injection, fixed for light or electron microscopic immunolocalization of biotin-tubulin-containing microtubules. When cel... |
2808435 | Fluorescent indicators for cytosolic sodium. | Fluorescent indicators sensitive to cytosolic concentrations of free Na+ have been synthesized and characterized. They consist of a crown ether, 1,7-diaza-4,10,13-trioxacyclopentadecane, linked via its nitrogens to fluorophores bearing additional liganding centers. In the currently preferred dye, SBFI (short for sodium... |
2808415 | Modeling low-pH hemoproteins. | A tetracoordinate ferrous heme (iron-porphyrin) has been proposed as an intermediate at low pH (less than 3.0) for respiratory hemoproteins, peroxidases, and model heme complexes. This intermediate is believed to arise via protonation of the N(epsilon) atom of the proximal histidine and consequent cleavage of the Fe-N(... |
2509436 | Trehalose accumulation in vegetative cells and spores of Myxococcus xanthus. | The disaccharide trehalose is found in the spores and cysts of a variety of organisms. We analyzed developing cells of Myxococcus xanthus for trehalose accumulation. Vegetative cells grown in media with low osmotic strengths contained less than 5 micrograms of trehalose per mg of protein. Spores formed in fruiting bodi... |
2553673 | Evidence that the Myxococcus xanthus frz genes are developmentally regulated. | The frizzy (frz) mutants of Myxococcus xanthus are unable to form fruiting bodies. Instead of forming discrete mounds, these strains aggregate as filaments which have a circular and tangled appearance. Mutations leading to this phenotype have been mapped to five complementation groups, frzA, frzB, frzCD, frzE, and frzF... |
2509425 | Patterns of cellular interactions during fruiting-body formation in Myxococcus xanthus. | Aggregation and mound formation during development of the myxobacterium Myxococcus xanthus were examined by scanning electron microscopy and light microscopy. Several complex patterns of multicellular associations were observed. These observations imply that complex, organized cell-cell interactions occur during the pr... |
2478472 | Molecular cloning of the Streptococcus mutans gene specifying antigen A. | A gene encoding a Streptococcus mutans surface protein antigen has been isolated from a strain GS-5 gene bank constructed via the Streptococcus-Escherichia coli shuttle vector pSA3. This E. coli recombinant clone, designated 4B2, expressed S. mutans proteins, as shown by Western immunoblot analysis with a specific rabb... |
2478182 | Radiation sensitivity of tumour cells stained in vitro or in vivo with the bisbenzimide fluorochrome Hoechst 33342. | The DNA-binding bisbenzimide fluorochrome Hoechst 33342 is being used routinely in radiobiological studies to assess cell kinetic parameters and tumour blood flow. However, there are reports in the literature which indicate that exposure to this compound can affect the radiation sensitivity of tumour cell populations. ... |
2552152 | Linker insertion mutants of simian virus 40 large T antigen that show trans-dominant interference with wild-type large T antigen map to multiple sites within the T-antigen gene. | Linker insertion mutants affecting the simian virus 40 (SV40) large tumor (T) antigen were constructed by inserting a 12-base-pair oligonucleotide linker into restriction endonuclease cleavage sites located within the early region of SV40. One mutant, with the insertion at amino acid 5, was viable in CV-1p and BSC-1 ce... |
2677399 | A recombinant hepatitis B core antigen polypeptide with the protamine-like domain deleted self-assembles into capsid particles but fails to bind nucleic acids. | We have cloned in Escherichia coli both the complete core gene of hepatitis B virus and a truncated version of it, leading to the synthesis of high levels of a core-antigen-equivalent polypeptide (r-p22) and of an e-antigen-equivalent polypeptide (r-p16), respectively. We then compared the structural and antigenic prop... |
2552139 | Receptor activity of rotavirus nonstructural glycoprotein NS28. | Rotavirus morphogenesis involves the budding of subviral particles through the rough endoplasmic reticulum (RER) membrane of infected cells. During this process, particles acquire the outer capsid proteins and a transient envelope. Previous immunocytochemical and biochemical studies have suggested that a rotavirus nons... |
18964877 | Preconcentration of lanthanides from natural waters with a lipophilic crown ether carboxylic acid. | Lipophilic crown ether carboxylic acids such as 2-(sym-dibenzo-16-crown-5-oxy)stearic acid with a cavity size comparable to the ionic radius of rare-earth elements are selective chelation agents for preconcentration and separation of lanthanides from natural waters for NAA. Interfering matrix elements such as sodium an... |
16812603 | Nonhuman short-term memory: A quantitative reanalysis of selected findings. | Intense interest in the experimental analysis of nonhuman short-term memory was occasioned by the "cognitive revolution" in the early 1970s. As researchers tested and refined their theoretical models, a sizable empirical literature on the subject rapidly emerged. Generally missing from that literature, however, is an i... |
2485887 | Neuropeptide Y (NPY)-like immunoreactive nerve fibers in the human and monkey (Macaca fascicularis) kidney. | Nerve fibers immunoreactive for neuropeptide Y (NPY) are demonstrated for the first time by the indirect immunofluorescence technique in the human and monkey kidney. NPY-like immunoactivity (NPY-LI) is shown in a bundle of nerve fibers in the surrounding connective tissue of arteries and to a lesser extent, veins, main... |
2633075 | [Multiple organ failure syndrome in infection caused by ictero-hemorragic Leptospira. Description of a clinical case]. | A 53 years old fisherman was admitted to General Intensive Care Unit in Arezzo with signs and symptoms of Weil disease. An early acute respiratory failure developed. Radiological and haemodynamic findings confirmed a diagnosis of ARDS. The patient developed a severe jaundice, acute renal failure and ARDS (MOF multiple ... |
2632221 | Fibroblast growth factor (FGF) induces different responses in lens epithelial cells depending on its concentration. | We reported previously that epithelial cells in explants from neonatal rat lenses, when cultured in the presence of fibroblast growth factor (FGF), showed increased proliferation, cell migration and fibre differentiation; moreover, fibre differentiation in response to the basic form of FGF (bFGF) was virtually complete... |
2698791 | [Treatment of 10 cases of multiple organ failure]. | From 1985 to 1987, 10 cases of multiple organ failure (MOF) caused by severe infection, major surgery, and trauma were treated in our hospital. The sequence of the organs that came to a failure varied with different diseases. The diagnosis was made on the objective index and numbers of the failed organs. All patients w... |
2624302 | Plasma levels of endotoxin and anaphylatoxin in patients with multiple organ failure. | Plasma concentrations of endotoxin and anaphylatoxins were studied inpatients with multiple organ failure (MOF). Thirty one blood samples from nine patients with MOF and twenty samples from preoperative patients as control were determined. The average plasma concentration of endotoxin was 188.7 +/- 37.0 pg-ml-1 (Mean +... |
2621567 | [Enhanced bioavailability of digoxin by gamma-cyclodextrin complexation: evaluation for sublingual and oral administrations in humans]. | The inclusion complex of digoxin with gamma-cyclodextrin was prepared in a molar ratio of 1:4, and evaluated for sublingual and oral administrations in humans. In the dissolution tests of digoxin tablets, the increase in dissolution rate and decrease in acid hydrolysis were attained by gamma-cyclodextrin complexation. ... |
2575652 | Regulation of cGMP levels by guanylate cyclase in truncated frog rod outer segments. | Cyclic GMP is the second messenger in phototransduction and regulates the photoreceptor current. In the present work, we tried to understand the regulation mechanism of cytoplasmic cGMP levels in frog photoreceptors by measuring the photoreceptor current using a truncated rod outer segment (tROS) preparation. Since exo... |
2559082 | The effect of cyclodextrin on lipopolysaccharide production in cultures of Bordetella pertussis. | The effect of adding 500 micrograms of (2,6-0-dimethyl) beta-cyclodextrin (Me-beta-CD) per ml of Stainer-Scholte (SS) medium in two-day shaker flask cultures of Bordetella pertussis on the production of lipopolysaccharide (LPS) was investigated. The amount of LPS per 10(9) cells found in the supernatants of these cultu... |
2533023 | [Evaluation of the antalgic activity and tolerability of piroxicam in chronic pain in cervicoarthrosis and lumboarthrosis]. | A study was carried out to assess the analgesic efficacy and the safety of piroxicam and to compare them with those of a piroxicam derivative, piroxicam beta-cyclodextrin, in chronic pain caused by arthritis of the neck and lower back. The drugs in question were administered for two weeks at the dose of 20 mg/die per o... |
2611938 | Epimerization and racemization of some chiral drugs in the presence of cyclodextrin and liposomes. | The effects of alpha-, beta-, gamma- and dimethyl-beta-cyclodextrins (alpha-, beta-, gamma- and DM-beta-CyDs) and liposomes on epimerization or racemization of etoposide, ethiazide and carbenicillin were examined kinetically. alpha- and beta-CyDs accelerated both epimerization and hydrolysis of carbenicillin. They had ... |
2611776 | O-carboxymethyl-O-ethylcyclomaltoheptaose as a delayed-release-type drug carrier: improvement of the oral bioavailability of diltiazem in the dog. | The utility of O-carboxymethyl-O-ethylcyclomaltoheptose (carboxymethyl-ethyl-beta-cyclodextrin, CME-beta CD) as a delayed-release-type drug carrier was investigated in vitro and in vivo, using diltiazem hydrochloride as a model drug. The aqueous solubility of CME-beta CD showed a marked dependency on pH, because of the... |
2611775 | Alkylation of cyclomalto-oligosaccharides (cyclodextrins) with dialkyl sulfate-barium hydroxide: heterogeneity of products and the marked effect of the size of the macrocycle. | The alkylation of cyclomalto-oligosaccharides (cyclodextrins, CDs) with dialkyl sulfate-barium hydroxide has been claimed to yield 2,6-di-O-alkyl derivatives. Re-investigation by plasma desorption-m.s. of the products of laboratory methylation of alpha CD, beta CD, or gamma CD and ethylation of beta CD and several comm... |
2611774 | The synthesis of an active derivative of cyclomaltoheptaose for the hydrolysis of esters and the formation of amide bonds. | The synthesis is described of a derivative of cyclomaltoheptaose (beta-cyclodextrin) to which the tripeptide Ser-His-Asp, the catalytic triad found in chymotrypsin, has been coupled. The derivative enhanced the rates of hydrolysis of activated esters, as measured by the release of p-nitrophenol, and the formation of am... |
2605171 | Flavin and heme structures in lactate:cytochrome c oxidoreductase: a resonance Raman study. | Resonance Raman spectra of Hansenula anomala L-lactate:cytochrome c oxidoreductase (or flavocytochrome b2), of its cytochrome b2 core, and of a bis(imidazole) iron-protoporphyrin complex were obtained at the Soret preresonance from the oxidized and reduced forms. Raman contributions from both the isoalloxazine ring of ... |
2593256 | [Fulminant autoimmune hemolytic anemia with multiple organ failure]. | We report a rare case of fulminant autoimmune hemolytic anemia (AIHA) with multiple organ failure (MOF). A 40-year-old man was emergently admitted to our hospital because of conscious disturbance and jaundice. The peripheral blood revealed RBC 68 x 10(4)/microliter, Hb 3.5 g/dl, Ht 8.9%, Ret 30% (20,400/microliter), WB... |
2531228 | Three-dimensional structure of cyclodextrin glycosyltransferase from Bacillus circulans at 3.4 A resolution. | Cyclodextrin glycosyltransferase (EC 2.4.1.19) from Bacillus circulans has been purified, crystallized and analyzed by X-ray diffraction. The enzyme is monomeric. SDS/polyacrylamide gel electrophoresis gave an Mr of 73,600(+/- 1000), corresponding to 670(+/- 10) amino acid residues. The structure of the crystalline enz... |
2684631 | Membrane interactions of diphtheria toxin analyzed using in vitro synthesized mutants. | We have developed a system to study the interactions of diphtheria toxin with the cell surface using non-toxic mutant proteins synthesized in vitro. Proteins obtained by N-terminal deletions containing the whole B fragment bound strongly to cells. Deletions extending into the B fragment did not yield an autonomous bind... |
2813364 | On the ion selectivity in Ca-binding proteins: the cyclo(-L-Pro-Gly-)3 peptide as a model. | Calcium plays a crucial role in many cellular processes. Its functions are directly dependent on the high specificity for Ca2+ exhibited by the proteins and ion carriers that bind divalent ions. To elucidate the basis for this specificity we have calculated the relative energies of solvation of calcium and magnesium io... |
2510154 | Identification of cellular proteins that bind to the human immunodeficiency virus type 1 trans-activation-responsive TAR element RNA. | Human immunodeficiency virus type 1 (HIV-1) trans-activator protein Tat activates the expression of its viral long terminal repeat (LTR) through a target transactivation-responsive element termed TAR. We have constructed cell lines that constitutively express the HIV-1 Tat protein. Analyses of nuclear proteins from the... |
2682624 | Heterologous expression of a wheat high molecular weight glutenin gene in Escherichia coli. | An engineered DNA fragment containing a DNA sequence encoding a wheat high molecular weight glutenin subunit was cloned into a bacterial expression vector that is based on bacteriophage T7 RNA polymerase. The resulting plasmid directed the synthesis of large amounts of the mature form of the wheat high molecular weight... |
2682622 | Refined apoprotein structure of rat intestinal fatty acid binding protein produced in Escherichia coli. | Rat intestinal fatty acid binding protein (I-FABP) is a member of a family of cytoplasmic hydrophobic ligand-binding proteins. To gain insights about the contribution of bound fatty acid to I-FABP's conformation and mechanism of ligand binding, we have determined the structure of Escherichia coli-derived rat apo-I-FABP... |
2806252 | Differential exposure of aromatic amino acids in the red-light-absorbing and far-red-light-absorbing forms of 124-kDa oat phytochrome. | The surface topography of aromatic amino acid residues and/or other hydrophobic groups of phytochrome has been investigated by ultraviolet absorption spectra and ultraviolet circular dichroism using phytochrome-cyclodextrin inclusion complexation. Three different types of cyclodextrins (alpha, beta and gamma) with vary... |
2680058 | Fluoroquinolone antimicrobial agents. | The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial tar... |
2799912 | Significance of lecithin:cholesterol acyltransferase activity as a prognostic indicator of early allograft function in clinical liver transplantation. | Rapid and accurate assessment of allograft function in the early postoperative period is critical for successful liver transplantation. This study evaluated the efficacy of lecithin:cholesterol acyltransferase (LCAT) activity as an indicator of early allograft function in human orthotopic liver transplantation (OLTx). ... |
2678109 | A genetically engineered cell line that produces empty capsids of B19 (human) parvovirus. | B19 parvovirus is pathogenic in humans, causing the common childhood exanthem fifth disease and bone-marrow failure, both acute (transient aplastic crisis of hemolysis) and chronic (pure erythrocyte aplasia in immunodeficiency). The virus is tropic for a human red cell progenitor cell, and failure to culture B19 in a c... |
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