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1416841 | Liquid chromatographic determination of ampicillin in bovine and dog plasma by using a tandem solid-phase extraction method. | The determination of ampicillin in plasma and serum by reversed-phase high-performance liquid chromatography with UV detection suffers from poor selectivity and sensitivity. Currently, the most common approach to overcoming these problems consists of improving the compound's detectability via pre- or postcolumn derivat... |
1383611 | A role for ELAM-1 in the pathogenesis of MOF during septic shock. | As a model for septic shock, LPS was infused into anesthetized Cynomolgus monkeys. Hematologic and metabolic parameters proved the induced shock response. The data presented show that administration of LPS to Cynomolgus monkeys induced a generalized inflammatory status, which was characterized by systemic release of th... |
1403733 | Lipidic peptides. V: Penicillin and cephalosporin acid conjugates with increased lipophilic character. | Lipophilic, double-ester derivatives of beta-lactam antibiotics with methylene, ethylene, and propylene spacers were prepared by crown-ether-assisted coupling of halogenoalkyl esters of 2-(tert-butoxycarbonylamino)decanoic acid to either penicillin G or cefuroxime. The hydroxyethyl ester of penicillin G and the tert-bu... |
1403730 | Prominent inclusion effect of dimethyl-beta-cyclodextrin on photoisomerization of the thromboxane synthetase inhibitor (E)-4-(1-imidazoylmethyl)cinnamic acid. | The direct photoisomerization of (E)-4-(1-imidazoylmethyl)-cinnamic acid (IMC), a thromboxane synthetase inhibitor, to its (Z)-isomer at pH 2.0 was decelerated by beta-cyclodextrin (beta-CyD) and heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CyD). The photostationary composition [(Z)-isomer:IMC ratio] was shifte... |
1403720 | Complexation of steroid hormones with cyclodextrin derivatives: substituent effects of the guest molecule on solubility and stability in aqueous solution. | The inclusion complexation of homologous derivatives of steroid hormones with cyclodextrins and 2-hydroxypropyl-beta-cyclodextrin (2-HP-beta-CD) was investigated with regard to underlying structure-interaction relationship. The interaction was studied by phase solubility analysis and stabilization effects of complex fo... |
1522022 | Synthesis and evaluation of technetium-99m monocationic mixed ligand complexes of phenyl substituted/condensed tetradentate Schiff's bases and trimethylphosphine. | Tc-99m monocationic mixed ligand complexes of phenyl substituted/condensed Schiff's bases, N,N'-ethylene-bis-(benzoylacetone imine) (Lb) or N,N'-ethylene-bis-(salicylaldehyde imine) (Lc) or N,N'-ethylene-bis-(2-hydroxyacetophenone imine) (Ld) and trimethylphosphine were synthesized to determine the influence of the pre... |
1518062 | Protein-ligand energetics assessed using deoxy and fluorodeoxy sugars in equilibrium binding and high resolution crystallographic studies. | Hydrogen bonding interactions are one of the most important single factors in protein-ligand interactions and molecular recognition. To probe the energetics of the interactions, we have analyzed the binding of 1-deoxy-, 2-deoxy- and 6-fluoro-6-deoxy- analogues of D-galactose (Gal) to a primary high-affinity periplasmic... |
1387481 | Inotropic influence of macrocyclic polyethers on tracheal smooth muscle. | Incubated guinea pig tracheal smooth muscle exhibited both positive and negative inotropic responses to a variety of crown ether analogs that ranged in size from 12-crown-4 to 30-crown-10 and included molecules whose lipophilicity was modified by the addition of benzo- and cyclohexo-substituents on the basic molecular ... |
1510917 | Helix formation in enzymically ligated peptides as a driving force for the synthetic reaction: example of alpha-globin semisynthetic reaction. | The alpha-globin semisynthetic reaction, namely, the ligation of the complementary fragments of alpha-globin, alpha 1-30 and alpha 31-141, in the presence of 30% l-propanol that is catalyzed by V8 protease is distinct as compared with the previously studied protease-catalyzed splicing of the discontinuity sites of the ... |
1510312 | Analgesia and behavioral responses of dogs given oxymorphone-acepromazine and meperidine-acepromazine after methoxyflurane and halothane anesthesia. | This study was designed to test analgesia, duration, and cardiovascular changes induced by meperidine (MEP) and oxymorphone (OXY) following methoxyflurane (MOF) and halothane (HAL) anesthesia. Eight healthy dogs were given atropine and acepromazine, and anesthesia was induced with thiamylal and maintained with 1.5 mini... |
1508722 | Multiple octamer binding sites in the promoter region of the bovine alpha s2-casein gene. | Using a set of overlapping oligonucleotides from the promoter region of the bovine alpha s2-casein gene we have identified two nuclear factors which probably are involved in expression of this gene and the related calcium sensitive alpha s1- and beta-casein genes. One of these factors which was present in extracts of a... |
1508713 | The promoter of the tgt/sec operon in Escherichia coli is preceded by an upstream activation sequence that contains a high affinity FIS binding site. | The tgt/sec operon in E. coli consists of five genes: queA, tgt, ORF12, secD, and secF. QueA and Tgt participate in the biosynthesis of the hypermodified t-RNA nucleoside Queuosine, whereas SecD and SecF are involved in protein secretion. Examination of the promoter region of the operon showed structural similarity to ... |
1324474 | Ellipticine increases the superhelical density of intracellular SV40 DNA by intercalation. | We investigated the in vivo effect of ellipticine, a mammalian topoisomeraseII(topoII) inhibitor, on SV40 DNA topology. In contrast to epipodophyllotoxins, ellipticine did not cause significant double stranded cleavage of intracellular SV40 DNA. Furthermore, ellipticine reduced cleavage induced by epipodophyllotoxins, ... |
1508680 | Enhancement of ribosomal frameshifting by oligonucleotides targeted to the HIV gag-pol region. | The pol gene of all retroviruses is expressed as a gag-pol fusion protein which is proteolytically processed to produce all viral enzymes. In the human immunodeficiency virus (HIV), the gag and pol genes overlap by 241 nucleotides with pol in the -1 phase with respect to gag. The gag-pol fusion is produced via a -1 rib... |
1508667 | In-cell PCR from mRNA: amplifying and linking the rearranged immunoglobulin heavy and light chain V-genes within single cells. | We describe a process for the identification of mRNAs within single cells, as demonstrated with the immunoglobulin (Ig) variable region (V) genes of two mouse hybridoma cell lines and the bcr-abl fusion gene of the human K562 myeloid leukaemia line. The cells were fixed and permeabilised, the mRNA reverse transcribed t... |
1503516 | Multiple organ failure. Pathophysiology and potential future therapy. | Multiple organ failure (MOF) has reached epidemic proportions in most intensive care units and is fast becoming the most common cause of death in the surgical intensive care unit. Furthermore, in spite of the development of successive generations of new and more powerful antibiotics and increasing sophisticated techniq... |
1502201 | The intrinsic helix-forming tendency of L-alanine. | Conformational energy calculations have been carried out for three hexadecapeptides in water--namely, a copolymer with the sequence acetyl-AAAAKAAAA-KAAAAKA-amide, 3K(I), in both the charged and neutral forms; a neutral peptide with the sequence acetyl-AAQAAAAQAAAAQAAY-amide, AQY; and a 16-residue L-alanine homopolymer... |
1323848 | Retinoic acid receptors initiate induction of the cytomegalovirus enhancer in embryonal cells. | Reactivation of latent virus is believed to result from a signal transduction event that induces immediate-early (IE) gene transcription. Evidence is presented that the major IE promoter (MIEP) of human cytomegalovirus (hCMV) is activated by physiological levels of retinoic acid (RA) in human embryonal carcinoma cells.... |
1323847 | Local translational diffusion rates of membranous Na+,K(+)-ATPase measured by saturation transfer ESR spectroscopy. | Diffusion-controlled Heisenberg spin exchange between spin-labeled Na+,K(+)-ATPase [ATP phosphohydrolase (Na+/K(+)-transporting), EC 3.6.1.37] proteins has been studied by saturation transfer ESR spectroscopy in reconstituted membranes. Na+,K(+)-ATPase from the salt gland of Squalus acanthias was solubilized in a polyo... |
1502144 | Toward rules relating zinc finger protein sequences and DNA binding site preferences. | Zinc finger proteins of the Cys2-His2 type consist of tandem arrays of domains, where each domain appears to contact three adjacent base pairs of DNA through three key residues. We have designed and prepared a series of variants of the central zinc finger within the DNA binding domain of Sp1 by using information from a... |
1500427 | In vitro and in vivo characterization of four fibroblast tropomyosins produced in bacteria: TM-2, TM-3, TM-5a, and TM-5b are co-localized in interphase fibroblasts. | Most cell types express several tropomyosin isoforms, the individual functions of which are poorly understood. In rat fibroblasts there are at least six isoforms; TM-1, TM-2, TM-3, TM-4, TM-5a, and TM-5b. TM-1 is the product of the beta gene. TM-4 is produced from the TM-4 gene, and TMs 2, 3, 5a, and 5b are the product... |
1499567 | Urokinase binding to laminin-nidogen. Structural requirements and interactions with heparin. | Recently we have shown that heparin and related sulfated polyanions are low-affinity ligands of the kringle domain in the amino-terminal region (ATF) of human urokinase (u-PA), and proposed that this may facilitate loading of u-PA onto its receptor at the focal contacts between adherent cells and their matrix. We have ... |
1498687 | A fast algorithm for counting the arrangements for packing identical items on a one-dimensional grid with application in DNA-protein and similar interactions. | An algorithm is described, originally developed for use with DNA-protein complexes, which precisely counts the number of possible arrangements for non-overlapping items, each occupying M points, on a lattice of N such points. The algorithm counts the total number of arrangements for a given number of items and can be r... |
1497625 | Solubilization of growth hormone and other recombinant proteins from Escherichia coli inclusion bodies by using a cationic surfactant. | Recombinant pig growth hormone (rPGH) was solubilized from inclusion bodies by using the cationic surfactant cetyltrimethylammonium chloride (CTAC). The solubilizing action of CTAC appeared to be dependent on the presence of a positively charged head group, as a non-charged variant was inactive. Relatively low concentr... |
1386734 | Genetic evidence for an androgen-regulated epididymal secretory glutathione peroxidase whose transcript does not contain a selenocysteine codon. | Epididymal glutathione peroxidase (GPX) has been suggested as a major factor in combating loss of fertility of spermatozoa due to lipid peroxidation. We report here the isolation and sequence of putative GPX cDNAs from rat (Rattus rattus) and cynomolgus-monkey (Macaca fascicularis) epididymis, which exhibit marked sequ... |
1496543 | The role of fibroblasts in dermal vascularization and remodeling of reconstructed human skin after transplantation onto the nude mouse. | The vascularization and the dermal remodeling of two different types of human skin reconstructed "in vitro" and grafted onto the nude mouse were studied. They were composed of human keratinocytes grown either on a human acellular deepidermized dermis (DED), or on a lattice composed of human fibroblasts embedded in bovi... |
1496014 | Conformation for a beta-cyclodextrin monosubstituted with a cyclic dipeptide. | The structural characterization of a beta-cyclodextrin monosubstituted with the peptide cyclo(L-His-L-Leu) is reported. This work provides an x-ray example of a covalently bound group that folds in such a way that the terminal apolar side chain is retained in the hydrophobic interior of the cone-shaped cyclodextrin cav... |
1496001 | Metal substitutions at the diiron sites of hemerythrin and myohemerythrin: contributions of divalent metals to stability of a four-helix bundle protein. | A general method is described for substitution of Mn(II) and Co(II) into the diiron sites of hemerythrin and myohemerythrin. Characterizations of these metal-substituted proteins show that their structures closely resemble those of the native proteins. In particular, the four-helix bundle structure appears to be mainta... |
1495980 | Quantitative effects of antihydrophobic agents on binding constants and solubilities in water. | The effects of urea and of guanidinium chloride on binding constants in water for 6-(4-tert-butylanilino)-naphthalene-2-sulfonate and of bis(p-tert-butylphenyl) phosphate binding to beta-cyclodextrin and to N,N'-bis(6-beta-cyclo-dextrinyl)imidazolium ion have been determined. Their effects on the water solubility of p-... |
1644768 | Isolation and characterization of ftsZ alleles that affect septal morphology. | The ftsZ gene encodes an essential cell division protein that specifically localizes to the septum of dividing cells. In this study we characterized the effects of the ftsZ2(Rsa) mutation on cell physiology. We found that this mutation caused an altered cell morphology that included minicell formation and an increased ... |
1644767 | Structure of the gene encoding cyclomaltodextrinase from Clostridium thermohydrosulfuricum 39E and characterization of the enzyme purified from Escherichia coli. | Clostridium thermohydrosulfuricum 39E, a gram-positive thermophilic anaerobic bacterium, produced a cyclodextrin (CD)-degrading enzyme, cyclodextrinase (CDase) (EC 3.2.1.54). The enzyme was purified to homogeneity from Escherichia coli cells carrying a recombinant multicopy plasmid that contained the gene encoding for ... |
1644754 | Type II DNA restriction-modification system and an endonuclease from the ruminal bacterium Fibrobacter succinogenes S85. | Fibrobacter succinogenes is an important cellulolytic bacterium found in the rumen and cecum of herbivores. Numerous attempts to introduce foreign DNA into F. succinogenes S85 have failed, suggesting the presence of genetic barriers in this organism. Results from this study clearly demonstrate that F. succinogenes S85 ... |
1644210 | A compendium of reviews in biochemistry and molecular biology published in the second half of 1991. | A compendium of reviews and mini-reviews in biochemistry and molecular biology published in the second half of 1991 is presented. In all 880 titles are listed from 108 different publications. This compendium presents the references by journal name--the most suitable format for a hardcopy of this information. Keywords h... |
1643657 | The small GTP-binding protein rho regulates the assembly of focal adhesions and actin stress fibers in response to growth factors. | Actin stress fibers are one of the major cytoskeletal structures in fibroblasts and are linked to the plasma membrane at focal adhesions. rho, a ras-related GTP-binding protein, rapidly stimulated stress fiber and focal adhesion formation when microinjected into serum-starved Swiss 3T3 cells. Readdition of serum produc... |
1639844 | Alzheimer-like paired helical filaments and antiparallel dimers formed from microtubule-associated protein tau in vitro. | Recent evidence from several laboratories shows that the paired helical filaments of Alzheimer's disease brains consist mainly of the protein tau in an abnormally phosphorylated form, but the mode of assembly is not understood. Here we use EM to study several constructs derived from human brain tau and expressed in Esc... |
1639073 | Sequence-specific interaction of the HMG box proteins TCF-1 and SRY occurs within the minor groove of a Watson-Crick double helix. | The high mobility group I (HMG) box is proposed to mediate DNA binding in a novel group of transcription-regulating proteins. Two of these, the proteins encoded by the T cell-specific TCF-1 and the mammalian sex-determining gene SRY, carry a single HMG box with specificity for the heptamer motif A/T A/T C A A A G. We h... |
1639066 | Mobile nucleosomes--a general behavior. | We have previously reported the mobility of positioned nucleosomes on sea urchin 5S rDNA. In this study we demonstrate the temperature dependence and the range of this mobility on 5S rDNA constructs. We find that this dynamic behavior also applies to bulk mononucleosomes and nucleosomes reconstituted onto sequences of ... |
1379174 | Two different protein kinases act on a different time schedule as glial filament kinases during mitosis. | Glial fibrillary acidic protein (GFAP) is a component of glial filaments specific to astroglia. We now report the spatial and temporal distributions of four phosphorylated sites in the GFAP molecule during mitosis of astroglial cells, determined by antibodies which can distinguish phosphorylated epitopes from non-phosp... |
1322116 | A prostacyclin analogue reduces free radical generation in heart-lung transplantation. | The mechanism by which prostacyclin acts to prevent in vivo reperfusion injury is still uncertain. This study was therefore undertaken to assess the effect of a stable prostacyclin analogue (OP 41483-alpha-CD [OP]) on oxygen-derived free radicals after heart-lung transplantation. OP was administered to the heart-lung g... |
1378535 | Genotoxic potential of crown ethers in mammalian cells: induction of sister-chromatid exchanges. | Crown ethers are macrocyclic polyethers which possess ionophoric properties. These compounds are currently being studied for potential use as pharmaceutical agents as well as antibacterials. Though crown ethers have been shown to be highly toxic in prokaryotes and eukaryotes, there have been few investigations into the... |
1630461 | The N-terminal 96 residues of MCM1, a regulator of cell type-specific genes in Saccharomyces cerevisiae, are sufficient for DNA binding, transcription activation, and interaction with alpha 1. | MCM1 performs several functions necessary for its role in regulating cell type-specific gene expression in the yeast Saccharomyces cerevisiae: DNA binding, transcription activation, and interaction with coregulatory proteins such as alpha 1. We analyzed a set of MCM1 deletion derivatives using in vivo reporter gene ass... |
1630448 | Inducible processing of interferon regulatory factor-2. | PRDI-BFc and PRDI-BFi are proteins that bind specifically to a regulatory element required for virus induction of the human beta interferon (IFN-beta). PRDI-BFc is a constitutive binding activity, while the PRDI-BFi binding activity is observed only after cells are treated with inducers such as virus or poly(I).poly(C)... |
1378506 | Specificity of Rous sarcoma virus nucleocapsid protein in genomic RNA packaging. | Site-directed mutagenesis has shown that the nucleocapsid (NC) protein of Rous sarcoma virus (RSV) is required for packaging and dimerization of viral RNA. However, it has not been possible to demonstrate, in vivo or in vitro, specific binding of viral RNA sequences by NC. To determine whether specific packaging of vir... |
1321268 | The Epstein-Barr virus nuclear protein 1 promoter active in type I latency is autoregulated. | The only member of the Epstein-Barr virus family of nuclear proteins (EBNAs) expressed during type I and type II latent infections is EBNA-1. This is in contrast to type III latency, during which all six nuclear proteins are expressed from a common transcription unit. The exclusive expression of EBNA-1 during type I an... |
1629158 | Light and oxygen regulation of the synthesis of bacteriochlorophylls a and c in Chloroflexus aurantiacus. | Control of the synthesis of bacteriochlorophylls (Bchls) a and c by light and oxygen was studied in Chloroflexus aurantiacus grown in batch or chemostat culture with serine as the growth-limiting substrate. For comparison, inhibition by gabaculine of the formation of selected tetrapyrroles was studied. The inhibitory e... |
18965477 | Thin-layer chromatography of laser dyes and dye analogs with cyclodextrins in the mobile phase. | The addition of beta-cyclodextrin and substituted hydroxyethyl and hydroxypropyl-beta-cyclodextrins to aqueous urea-containing mobile phases, can be used to enhance the migration of various laser dyes on thin layer chromatography. Selected laser dyes from the coumarin, rhodamine and bimane families were examined, as we... |
18965473 | A comparison of gradient capacity anion chromatography using macrocycles D-2.2.2 and D-2.2.1 in constant or variable temperature mode. | The ability of macrocyclic ligands to complex alkali metal cations has been exploited to perform chromatographic separations of anions. Macrocycles adsorbed to reversed phase columns can complex eluent cations, thus generating anion exchange sites. Gradient separations of anions can be performed by changing the column ... |
1304374 | Charge balance in the alpha-hydroxyacid dehydrogenase vacuole: an acid test. | The proposal that the active site vacuole of NAD(+)-S-lactate dehydrogenase is unable to accommodate any imbalance in electrostatic charge was tested by genetically manipulating the cDNA coding for human muscle lactate dehydrogenase to make a protein with an aspartic acid introduced at position 140 instead of the wild-... |
1303146 | Different effects of L-, N- and T-type calcium channel blockers on striatal dopamine release measured by microdialysis in freely moving rats. | Using a microdialysis method, we have investigated effects of the voltage-dependent calcium channel blockers, verapamil, nicardipine, omega-conotoxin and flunarizine on the dopamine release and metabolism in the striatum of freely moving rat. Perfusion of verapamil (1-300 microM) and nicardipine (1-100 microM), an L-ty... |
1301340 | [Multiple organ failure following severe acute pancreatitis: its clinically patterns and pathogenetic factors]. | To detect the clinical course and possible pathogenetic factors of multiple organ failure (MOF) after severe acute pancreatitis (SAP), we investigated retrospectively 70 consecutive patients with SAP for a 16-year period. Two different patterns of MOF were identified: rapid-single phase MOF developed early after SAP at... |
1432596 | [Prostaglandins: synthetic and pharmacological studies and development]. | The therapeutic use of prostaglandins (PGs) which contain various biological activities and are unstable was successfully achieved. PGs were produced in a large scale according to the Corey method and could be stabilized by the formation of a clathrate compound with cyclodextrin, which enabled the production of marketa... |
1420877 | Implications of epidermal growth factor (EGF) induced egf receptor aggregation. | To investigate the role of receptor aggregation in EGF binding, we construct a mathematical model describing receptor dimerization (and higher levels of aggregation) that permits an analysis of the influence of receptor aggregation on ligand binding. We answer two questions: (a) Can Scatchard plots of EGF binding data ... |
1420475 | The enantiomeric resolution of ciprofibrate and related compounds by HPLC using chiral stationary phases. | The attempted chromatographic resolution of the drug ciprofibrate and a range of related compounds, containing the chiral moiety 2,2-dichlorocyclopropylbenzene, using five different chiral stationary phases is described. Aqueous mobile phases were used throughout and the successful separation of nine out of 12 pairs of... |
1413261 | Scanning force microscopy studies of the S-layers from Bacillus coagulans E38-66, Bacillus sphaericus CCM2177 and of an antibody binding process. | In many prokaryotic cells (eubacteria and archaebacteria) the outermost cell envelope component is composed of a regularly structured protein surface layer (S-layer). The two-dimensional S-layer from Bacillus coagulans E38-66 and Bacillus sphaericus CCM2177 has been investigated by SFM at molecular resolution under phy... |
1404892 | [Amino acids metabolism and nutritional support in acute renal failure]. | It has been claimed that conventional essential amino acid (EAA) solution may give rise to adverse effects such as hyperammonemia, in acute renal failure (ARF). On the other hand the majority the ARF treated recently have been complicated by multiple organ failure (MOF). These data indicate that a new regimen in nutrit... |
1403704 | Improvements in solubility and stability of thalidomide upon complexation with hydroxypropyl-beta-cyclodextrin. | Thalidomide is in clinical use for the treatment of graft-versus-host disease in leukemia patients after bone marrow transplant. Low levels of the drug in plasma after oral administration have made an intravenous thalidomide formulation desirable. Thalidomide, however, is sparingly soluble in aqueous solution (50 micro... |
1403488 | Preparation and physical evaluation of microcapsules of hydrophilic drug-cyclodextrin complexes. | An emulsion-solvent evaporation method for preparation of microcapsules containing water-soluble 2-hydroxypropyl-beta-cyclodextrin complex of a lipophilic water-insoluble drug, hydrocortisone, is described. The release of the drug from the microcapsules was determined in simulated gastric fluid. The drug release rate f... |
1521465 | Influence of vehicle and anterior chamber protein concentration on cyclosporine penetration through the isolated rabbit cornea. | The transcorneal penetration of cyclosporine A has been determined from each of three vehicles across isolated cornea into simulated aqueous humor containing either 50 mg % protein (0.5 mg/ml; as found in a normal eye) or 5000 mg % protein (50 mg/ml; as found in an inflamed eye). Cyclosporine entered the corneal epithe... |
1518792 | Bipartite organization of the Bacillus subtilis endo-beta-1,4-glucanase revealed by C-terminal mutations. | The C-terminal boundary of primary sequence of the Bacillus subtilis PAP115 endo-beta-1,4-glucanase (EG) required for stable catalytic activity has been mapped by site-directed mutagenesis using Escherichia coli as host. The 52 kDa cel gene product, EG470 and a 33 kDa mutant (EG300), lacking 170 residues through a nons... |
1518411 | Interaction of omeprazole with DNA in rat tissues. | There has been concern recently over the possible genotoxicity of omeprazole, a potent inhibitor of gastric acid secretion in humans. In order to investigate its possible DNA binding activity in vivo, 14C-labelled omeprazole was administered to male PVG rats, 8-10 weeks old, orally by gavage at a dose of 30 mg/kg. At v... |
1515076 | Cystatin mimicry by synthetic peptides. | Synthetic peptides which tentatively mimic the cystatin inhibitory surface were used to study the mechanism of inhibition of cysteine proteinases by their natural inhibitors. The inhibitory properties of these peptides depend mainly on the presence of the QxVxG consensus sequence. N and C-terminal peptide derivatives b... |
1514688 | Continuous spectrophotometric assay for restriction endonucleases using synthetic oligodeoxynucleotides and based on the hyperchromic effect. | A continuous spectrophotometric assay for the EcoRV restriction endonuclease has been developed. The synthetic self-complementary oligonucleotide d(GACGATATCGTC) (which is double stranded under the assay conditions) is used as the substrate. The EcoRV endonuclease recognizes d(GATATC) sequences cutting between the cent... |
1504345 | Preservation and visualization of molecular structure in detergent-extracted whole mounts of cultured cells. | Today's electron microscopes have a resolution sufficient to resolve supramolecular structures. However, the methods used to prepare biological samples for electron microscopy often limit our ability to achieve the resolution that is theoretically possible. We use whole mounts of detergent-extracted cells grown on Form... |
1502981 | [The immunosuppressive effects of 0.025% cyclosporin eye drops in alpha cyclodextrin on rabbit corneal allografts]. | We reported the ocular penetration of cyclosporin (CYA) and the immunosuppressive effect of rabbit corneal allograft using 0.025% CYA eye drops in alpha-cyclodextrin (alpha-CD). Local application using 0.025% CYA in alpha-CD showed the concentration of 4,133 ng/gr in the cornea, but no detectable levels in aqueous humo... |
1643240 | DNA associations: packing calculations in A-, B-, and Z-DNA structures. | A detailed theoretical study has been carried out to examine the modes of DNA-DNA interactions on the basis of hard-sphere contact criteria. Two helices of identical structure and length are oriented side-by-side and their relative positions are controlled by translations along and rotations about specific axes. Short ... |
1643088 | Regulation of the GM1-galactosidase supramolecular structure and catalytic activity in vitro. | Regulation of the supramolecular organization and the catalytic activity of GM1-galactosidase (EC 3.2.1.23) and neuraminidase (EC 3.2.1.18) from human kidney was studied in a system of hydrated reversed micelles of Aerosol OT in octane. It was shown that both the catalytic activity and the oligomeric structure of the G... |
1641664 | The roles of fibrinogen and fibrin in hemostasis and thrombosis. | Proteolytic conversion of fibrinogen to fibrin results in self-assembly to form a clot matrix that subsequently becomes cross-linked by fXIIIa to form the main structural element of the thrombus in vivo. Fibrin formation and assembly lead to new properties that regulate the rate and extent of clotting, cross-linking, a... |
1322526 | The cleavage of DNA at phosphorothioate internucleotidic linkages by DNA gyrase. | We have constructed a plasmid which contains 22 copies of a 147 bp DNA fragment which contains the major DNA gyrase cleavage site from plasmid pBR322 (located at base-pair 990). We have found that this fragment is efficiently bound and cleaved by gyrase. The selectivity for the sequence corresponding to position 990 in... |
1638046 | Differences in the conformational state of a zinc-finger DNA-binding protein domain occupied by zinc and copper revealed by electrospray ionization mass spectrometry. | Transition metal ions are important in biological regulation partly because they can bind to and stabilize protein surface domain structures in specific conformations that are involved in key molecular recognition events. There are two C2-C2 type zinc-finger sequences within the highly conserved DNA-binding domain of t... |
1637342 | Use of rosy mutant strains of Drosophila melanogaster to probe the structure and function of xanthine dehydrogenase. | The usefulness in structure/function studies of molybdenum-containing hydroxylases in work with rosy mutant strains of Drosophila melanogaster has been investigated. At least 23 such strains are available, each corresponding to a single known amino acid change in the xanthine dehydrogenase sequence. Sequence comparison... |
1322134 | Bovine inositol monophosphatase. Modification, identification and mutagenesis of reactive cysteine residues. | 1. Bovine inositol monophosphatase reacts with thiol reagents such as 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB), N-ethylmaleimide (NEM) and iodoacetic acid (IAA). 2. Modification by NEM results in nearly total loss of enzyme activity, whereas modification by IAA causes a slight increase in activity. 3. The loss of ac... |
1637299 | Tyr-143 facilitates interdomain electron transfer in flavocytochrome b2. | The role of Tyr-143 in the catalytic cycle of flavocytochrome b2 (L-lactate:cytochrome c oxidoreductase) has been examined by replacement of this residue with phenylalanine. The electron-transfer steps in wild-type and mutant flavocytochromes b2 have been investigated by using steady-state and stopped-flow kinetic meth... |
1379038 | Mapping of the epitope/paratope interactions of a monoclonal antibody directed against adenosine 3',5'-monophosphate. | A series of systematically modified cyclic AMP (cAMP) analogues, including newly synthesized benzimidazole ribofuranosyl 3',5'-monophosphates was used to map the essential molecular interactions between cAMP and the monoclonal antibody 4/2C2 (mab 4/2C2) directed against 2'-O-succinoyl cAMP [Colling, Gilles, Nass, Moka ... |
1344026 | Incommensurate oxygen consumption in response to maximal oxygen availability predicts postinjury multiple organ failure. | Untreated flow-dependent oxygen consumption (VO2) has recently been implicated as an unrecognized risk factor for multiple organ failure (MOF). We therefore prospectively studied 39 severely injured patients with known risk factors for multiple organ failure who were subjected to an established resuscitation protocol a... |
1378852 | Autoantibodies associated with lupus induced by diverse drugs target a similar epitope in the (H2A-H2B)-DNA complex. | IgG reactivity with the (H2A-H2B)-DNA complex, a subunit of the nucleosome, has been detected in many patients with lupus induced by procainamide and quinidine, but the similarity among the epitopes targeted by these antibodies in this heterogeneous patient group as well as the prevalence of this specificity in lupus i... |
1633817 | O-glycosylation and stability. Unfolding of glucoamylase induced by heat and guanidine hydrochloride. | We have examined the stabilities of the catalytic and binding domains of glucoamylase 1 from Aspergillus niger and how these stabilities are affected by the O-glycosylated linker glycopeptide which separates the domains. On heating, the catalytic domain unfolds irreversibly, whereas the binding domain unfolds reversibl... |
1385982 | Chemical modification of cyclomaltodextrin glucanotransferase from Bacillus circulans var. alkalophilus. | Counting of integral numbers of cysteine residues of the reduced and denaturated form of cyclomaltodextrin glucanotransferase (CGTase) from Bacillus circulans var. alkalophilus (ATCC 21783) showed two cysteine residues per enzyme molecule. Titrations of the enzyme with 5,5'-dithiobis-(2-nitrobenzoic acid) led to the sa... |
1378718 | Angiogenesis and rheumatoid arthritis: pathogenic and therapeutic implications. | Rheumatoid arthritis can be considered as one of the family of 'angiogenesis dependent diseases'. Angiogenesis in rheumatoid arthritis is controlled by a variety of factors found in the synovial fluid and pannus tissue. Modulation of the angiogenic component of the disease may alter the pathogenesis of the condition, a... |
1631168 | Crystal structure determination at 2.3-A resolution of human transthyretin-3',5'-dibromo-2',4,4',6-tetrahydroxyaurone complex. | The crystal structure of the complex of 3',5'-dibromo-2',4,4',6-tetrahydroxyaurone, a flavone derivative, with human transthyretin (TTR), a serum thyroid hormone transport protein, has been determined and refined to R = 17.9% for data to 2.3-A resolution and provides a detailed description of a protein-bound flavonoid ... |
1631077 | Side-chain entropy opposes alpha-helix formation but rationalizes experimentally determined helix-forming propensities. | In recent host-guest studies, the helix-forming tendencies of amino acid residues have been quantified by three groups, each obtaining similar results [Padmanabhan, S., Marqusee, S., Ridgeway, T., Laue, T. M. & Baldwin, R. L. (1990) Nature (London) 344, 268-270; O'Neil, K. T. & DeGrado, W. F. (1990) Science 250, 646-65... |
1352879 | Design and synthesis of a CD4 beta-turn mimetic that inhibits human immunodeficiency virus envelope glycoprotein gp120 binding and infection of human lymphocytes. | Poor bioavailability, rapid degradation, antigenicity, and high cost often limit the use of proteinaceous pharmaceuticals. One goal of structural biochemistry is the reduction of complex molecules to small functional units that are amenable to high-resolution structural analysis and rapid modification. The dissection o... |
1630914 | Expression of wild-type and mutant p53 proteins by recombinant vaccinia viruses. | To facilitate the purification of wild type p53 protein, we established a recombinant p53 vaccinia viral expression system. Using this efficient eukaryotic expression vector, we found that the expressed p53 proteins retained their specific structural characteristics. A comparison between wild type and mutant p53 protei... |
1630912 | Synthesis and physical properties of anti-HIV antisense oligonucleotides bearing terminal lipophilic groups. | A number of phosphoramidite monomers have been prepared and used in the synthesis of antisense phosphorothioate oligonucleotides bearing 5'-polyalkyl and cholesterol moieties. Similar groups have also been attached to the 3'-end of oligonucleotides by means of functionalised CPG. Melting temperatures of duplexes formed... |
1629242 | Topology and phosphorylation of soybean nodulin-26, an intrinsic protein of the peribacteroid membrane. | Soybean nodulin-26, a homologue of bovine eye lens major intrinsic protein (MIP-26), is an integral protein of the peribacteroid membrane in symbiotic root nodules. It comprises 271 amino acids with six potential transmembrane domains and lacks an amino-terminal signal sequence. A full-length nodulin-26 cDNA and its va... |
1629240 | A fibronectin self-assembly site involved in fibronectin matrix assembly: reconstruction in a synthetic peptide. | The active form of fibronectin is its extracellular matrix form, which allows for the attachment of cells and influences both the growth and migration of cells. The matrix form is assembled by cells; however, many cells are defective in this regard. Several regions within fibronectin have been shown to play a role in m... |
1629239 | Kinetochore microtubules in PTK cells. | We have analyzed the fine structure of 10 chromosomal fibers from mitotic spindles of PtK1 cells in metaphase and anaphase, using electron microscopy of serial thin sections and computer image processing to follow the trajectories of the component microtubules (MTs) in three dimensions. Most of the kinetochore MTs ran ... |
1352758 | Molecular cloning of a gene (cfp) encoding the cytoplasmic filament protein P59Nc and its genetic relationship to the snowflake locus of Neurospora crassa. | P59Nc is a 59-kD polypeptide associated with 8-10-nm diameter cellular filaments in normal Neurospora crassa strains. Abnormally sized and shaped bundles of these structures are present in N. crassa strains carrying mutations at the locus sn (snowflake). By using molecular cloning and restriction fragment length polymo... |
1628664 | Purification and characterization of a novel thermostable 4-alpha-glucanotransferase of Thermotoga maritima cloned in Escherichia coli. | Maltodextrin glycosyltransferase (4-alpha-glucanotransferase) of the extremely thermophilic ancestral bacterium Thermotoga maritima has been purified from an Escherichia coli clone expressing the corresponding T. maritima MSB8 chromosomal gene. T. maritima 4-alpha-glucanotransferase, an approximately 53-kDa monomeric e... |
1628625 | Primary structure and binding activity of the hnRNP U protein: binding RNA through RGG box. | Heterogeneous nuclear ribonucleoproteins (hnRNPs) are thought to influence the structure of hnRNA and participate in the processing of hnRNA to mRNA. The hnRNP U protein is an abundant nucleoplasmic phosphoprotein that is the largest of the major hnRNP proteins (120 kDa by SDS-PAGE). HnRNP U binds pre-mRNA in vivo and ... |
1628617 | Amphiphysin, a novel protein associated with synaptic vesicles. | To obtain access to novel proteins of the neuronal synapse, we have raised antisera against proteins of synaptic plasma membranes and used them for immunoscreening brain cDNA expression libraries. One of the newly isolated cDNAs encodes an acidic protein of 75 kDa with a distinct architecture of structural domains and ... |
1321031 | Targeted degradation of the retinoblastoma protein by human papillomavirus E7-E6 fusion proteins. | The E6 and the E7 proteins of the oncogenic human papillomavirus types 16 and 18 can stably associate with p53 and the retinoblastoma protein, respectively. The E6-p53 interaction results in the accelerated degradation of p53 in vitro via the ubiquitin-dependent proteolysis system. In this study we demonstrate that a f... |
1628612 | Mutations of Ha-ras p21 that define important regions for the molecular mechanism of the SDC25 C-domain, a guanine nucleotide dissociation stimulator. | The SDC25 C-domain is a very active guanine nucleotide dissociation stimulator (GDS) isolated from Saccharomyces cerevisiae which acts equally well on Ha-ras p21 and yeast RAS2. These properties make the SDC25 C-domain a suitable tool to study the basic mechanism of a GDS. The action of the SDC25 C-domain was analysed ... |
1385723 | Labeling the (Ca(2+)-Mg2+)-ATPase of sarcoplasmic reticulum with 4-(bromomethyl)-6,7-dimethoxycoumarin: detection of conformational changes. | The (Ca(2+)-Mg2+)-ATPase of sarcoplasmic reticulum was labeled with 4-(bromomethyl)-6,7-dimethoxycoumarin. It was shown that a single cysteine residue (Cys-344) was labeled on the ATPase, with a 25% reduction in steady-state ATPase activity and no reduction in the steady-state rate of hydrolysis of p-nitrophenyl phosph... |
1624466 | Molecular modelling of the three-dimensional structure and conformational flexibility of bacterial lipopolysaccharide. | Molecular modelling techniques have been applied to calculate the three-dimensional architecture and the conformational flexibility of a complete bacterial S-form lipopolysaccharide (LPS) consisting of a hexaacyl lipid A identical to Escherichia coli lipid A, a complete Salmonella typhimurium core oligosaccharide porti... |
1624465 | Ferric iron uptake in Erwinia chrysanthemi mediated by chrysobactin and related catechol-type compounds. | Erwinia chrysanthemi 3937 possesses a saturable, high-affinity transport system for the ferric complex of its native siderophore chrysobactin, [N-alpha-(2,3-dihydroxybenzoyl)-D-lysyl-L-serine]. Uptake of 55Fe-labeled chrysobactin was completely inhibited by respiratory poison or low temperature and was significantly re... |
1624428 | Increase of sensitivity to aminoglycoside antibiotics by polyamine-induced protein (oligopeptide-binding protein) in Escherichia coli. | The sensitivity of Escherichia coli to several aminoglycoside antibiotics was examined with E. coli DR112 transformed by the gene for polyamine-induced protein (oligopeptide-binding [OppA] protein) or polyamine transport proteins. The results clearly showed that sensitivity to aminoglycoside antibiotics (gentamicin, is... |
1620124 | Differential binding of heterogeneous nuclear ribonucleoproteins to mRNA precursors prior to spliceosome assembly in vitro. | We have investigated the composition of the earliest detectable complex (H) assembled on pre-mRNA during the in vitro splicing reaction. We show that most of the proteins in this complex correspond to heterogeneous nuclear ribonucleoproteins (hnRNP), a set of abundant RNA-binding proteins that bind nascent RNA polymera... |
1368266 | Loops and secondary structure mimetics: development and applications in basic science and rational drug design. | One goal of protein design and structural biochemistry is the reduction of complex molecules to small functional units that are amenable to high resolution analysis and rapid modification. We have developed a variety of small molecules which biochemically and biologically mimic the combining sites of proteins of the im... |
1319407 | Propionate induces polymorphonuclear leukocyte activation and inhibits formylmethionyl-leucyl-phenylalanine-stimulated activation. | Short-chain carboxylic acids (SCCA) are metabolic by-products of bacterial pathogens which can alter cytoplasmic pH and inhibit a variety of polymorphonuclear leukocyte (PMN) motile functions. Since cytoskeletal F-actin alterations are central to PMN mobility, in this study we examined the effects of SCCA on cytoskelet... |
1612734 | In vivo effects of the antiglucocorticoid RU 486 on glucocorticoid and cytokine responses to Escherichia coli endotoxin. | The endogenous adrenocortical response to sepsis is critical for host survival. The in vivo interactions among the endogenous glucocorticoid response, the induction of cytokines, and host survival during endotoxemia were explored in this study by use of the glucocorticoid receptor antagonist RU 486. Male Lewis rats und... |
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