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1961705 | In vitro assembly of apophytochrome and apophytochrome deletion mutants expressed in yeast with phycocyanobilin. | Recombinant pea type I phytochrome apoprotein expressed in yeast is shown to assemble in vitro with phycocyanobilin to produce a photoreversible phytochrome-like adduct. As an initial investigation of the amino acid sequence requirements for chromophore incorporation, three phyA gene product deletion mutants were produ... |
1956399 | Structural studies of membranes and surface layers up to 1,000 A thick using X-ray standing waves. | The X-ray standing wave (XSW) method, developed in the 1960s, was used originally to determine heavy atom positions in and on silicon and germanium single crystals. An X-ray standing wave generated by the interference of coherent incident and reflected beams excites X-ray fluorescence from the heavy atom, the intensity... |
1955479 | Control of mammary epithelial differentiation: basement membrane induces tissue-specific gene expression in the absence of cell-cell interaction and morphological polarity. | Functional differentiation in mammary epithelia requires specific hormones and local environmental signals. The latter are provided both by extracellular matrix and by communication with adjacent cells, their action being intricately connected in what appears to be a cascade of events leading to milk production. To dis... |
1955331 | An improved method for determining 89Sr and 90Sr in urine. | A method has been developed for the rapid isolation and quantitation of 89Sr and 90Sr in urine samples. The radiostrontium is concentrated from the bulk urine sample by coprecipitation with calcium phosphate. The precipitate is then wet ashed with nitric acid, and a solution of the resulting residue in 2 M HNO3-0.5 M A... |
1944292 | Genetic and physical analyses of sister chromatid exchange in yeast meiosis. | We have used nonessential circular minichromosomes to monitor sister chromatid exchange during yeast meiosis. Genetic analysis shows that a 64-kb circular minichromosome undergoes sister chromatid exchange during 40% of meioses. This frequency is not reduced by the presence of a homologous linear minichromosome. Furthe... |
1944269 | Properties of the DNA-binding domain of the Saccharomyces cerevisiae STE12 protein. | The STE12 protein of the yeast Saccharomyces cerevisiae binds to the pheromone response element (PRE) present in the upstream region of genes whose transcription is induced by pheromone. Using DNase I footprinting assays with bacterially made STE12 fragments, we localized the DNA-binding domain to 164 amino acids near ... |
1944268 | Characterization of the mouse granulocyte-macrophage colony-stimulating factor (GM-CSF) gene promoter: nuclear factors that interact with an element shared by three lymphokine genes--those for GM-CSF, interleukin-4 (IL-4), and IL-5. | The region extending from -40 to -54 of the 5'-flanking region of the mouse granulocyte-macrophage colony-stimulating factor (GM-CSF) gene shows homology to sequences found in the 5'-flanking regions of other cytokine genes, those encoding interleukin-4 (IL-4), IL-5, and granulocyte colony-stimulating factor (G-CSF). T... |
1658396 | Herpes simplex virus type 1 Fc receptor protects infected cells from antibody-dependent cellular cytotoxicity. | Recent studies indicate that the herpes simplex virus type 1 (HSV-1) Fc receptor (FcR) can bind antiviral immunoglobulin G by participating in antibody bipolar bridging. This occurs when the Fab domain of an immunoglobulin G molecule binds to its antigenic target and the Fc domain binds to the HSV-1 FcR. In experiments... |
1658383 | Host range, replicative, and cytopathic properties of human immunodeficiency virus type 1 are determined by very few amino acid changes in tat and gp120. | Human immunodeficiency virus type 1 (HIV-1) isolates display differences in a variety of in vitro biological properties, including the ability to infect different cell types, the kinetics of replication, and cytopathicity in the infected cells. Studies with isolates obtained from the same individual over time have show... |
1658359 | trans activation of the simian virus 40 late promoter by large T antigen requires binding sites for the cellular transcription factor TEF-1. | Simian virus 40 (SV40) T antigen stimulates the level of transcription from several RNA polymerase II promoters, including the SV40 late promoter. The mechanism of trans activation appears to be indirect since binding of T antigen to specific DNA sequences is not required. However, specific promoter elements that respo... |
1658171 | Critically ill anergic patients demonstrate polymorphonuclear neutrophil activation in the intravascular compartment with decreased cell delivery to inflammatory focci. | Skin test anergy, the failure to produce a delayed type hypersensitivity (DTH) response, is associated with an increase in infection-related complications and death usually due to multiple organ failure (MOF). Refractory intravascular activation of polymorphonuclear neutrophils (PMNs) has been implicated in the develop... |
1937798 | High-affinity binding of the basement membrane proteins collagen type IV and laminin to the gastric pathogen Helicobacter pylori. | The ability of 16 isolates of the human gastroduodenal pathogen Helicobacter pylori to bind 125I-radiolabelled tissue proteins was quantitated by liquid-phase assay. While capable of binding generally low levels of collagen types I and II, vitronectin, and fibronectin (average binding, 8%; highest binding, 23%), the va... |
1821372 | Are genotoxic carcinogens more potent than nongenotoxic carcinogens? | In this report we have raised the question whether genotoxic carcinogens are more potent than nongenotoxic carcinogens when studied in long-term carcinogenicity assays in rodents. To build a large database of compounds for which both carcinogenicity and genotoxicity had been investigated, we have used a database produc... |
1818811 | [Pathological changes in immune defense system of multiple-organ failure rat and their action on pathogenesis]. | To explore the action of immune defense system on the mechanisms of MOF, Wistar rat MOF model was made by peritoneal injection of Zymosan. The pathological changes of MOF and the effects of neutrophils, platelets, MPS and some immune organs on MOF were studied with light and electron microscopy and image pattern analys... |
1816681 | [Anticoagulants of the nondialyzed fractions of the ammonia extract of the herb Pulmonaria mollissima]. | T-100 anticoagulants non-dialyzed through cellophane are isolated from ammonia extract of herb Pulmonaria mollissima. Their effect is mainly realized at the stage of coagulation conversions of fibrinogen, first of all at the stage of fibrin self-assembly. One of these anticoagulants is a peptide, another one is a glyco... |
1811853 | The crystal structure of the inclusion complex of cyclo-maltoheptaose (beta-cyclodextrin) with 3,3-dimethylbutylamine. | The crystal of the 1:1 complex of 3,3-dimethylbutylamine with cyclomaltoheptaose (beta CD, beta-cyclodextrin) is monoclinic C2 with a = 19.187(9), b = 24.56(1), c = 15.893(7) A, beta = 108.77(4) degrees, V = 7091 A3, and Z = 4. Two beta CD molecules, held together by intermolecular hydrogen bonds involving HO-3, form d... |
1725686 | Reversible rat mesenteric mast cell swelling caused by vagal stimulation or sham-feeding. | Fragments of rat mesentery were examined using acetylthiocholine to detect cholinergic nerve fibers and toluidine blue to identify mast cells. 59.2 +/- 2.6 percent of mast cells were at less than one-half mean cell diameter (4-5 microns), from the nerve fibers. Under the electron microscope, the membrane of mast cells ... |
1667090 | Specific association of an M-phase kinase with isolated mitotic spindles and identification of two of its substrates as MAP4 and MAP1B. | Isolated mammalian (Chinese hamster ovary [CHO]) metaphase spindles were found to be enriched in a histone H1 kinase whose activity was mitotic-cycle dependent. Two substrates for the kinase were identified as MAP1B and MAP4. Partially purified spindle kinase retained activity for the spindle microtubule-associated pro... |
1725495 | Molecular recognition between ligands and nucleic acids: DNA binding characteristics of analogues of Hoechst 33258 designed to exhibit altered base and sequence recognition. | The DNA binding characteristics of new analogues (2-8) of Hoechst 33258 (1), containing pyridine and benzoxazole units and designed for altered base specificity, were evaluated using UV, fluorescence, and circular dichroism studies. Like Hoechst 33258 the new analogues also bind through the minor groove of B-DNA in a n... |
1839608 | [Monoclonal antibodies to cyclodextrin-glycosyltransferase from Bacillus macerans]. | Cyclodextrin glycosyltransferase (CGTase, EC 2.4.1.19) was isolated from the cell-free culture medium of Bacillus macerans strain BKMB-506. The purified enzyme was used to immunize BALB/c mice. Polyclonal antibodies (PAbs) and 15 hybridoma cells producing monoclonal antibodies (MAbs) against CGTase were obtained. The p... |
1805978 | [Problems of biomimetic chemistry]. | The main goals of biomimetic chemistry have been formulated on the basis of the concept of biochemical organization. Biomimetic chemistry is defined as a science which employs the principles of biochemical organization (i. e., the principles of structural organization, functioning and regulation of biological systems a... |
1805938 | Antibody labeling with copper-67 using the bifunctional macrocycle 4-[(1,4,8,11-tetraazacyclotetradec-1-yl)methyl]benzoic acid. | The high kinetic stability of the Cu2+ complex of the chelator 4-[(1,4,8,11-tetraazacyclotetradec-1-yl)-methyl]benzoic acid was demonstrated at physiological pH as well as under acidic conditions. The chelating agent was conjugated to AB35, a monoclonal antibody directed against CEA, without a significant loss of immun... |
1802981 | Solubilization of ovine growth hormone with 2-hydroxypropyl-beta-cyclodextrin. | Studies were undertaken to determine the effects of 2-hydroxypropyl-beta-cyclodextrin (HPCD) on the solubility of ovine-Growth Hormone (o-GH) in aqueous solution. HPCD, which is believed to form inclusion complexes with hydrophobic amino acid residues of peptides, markedly increased o-GH solubility at all o-GH and all ... |
1838375 | Investigation of the active site of Bacillus macerans cyclodextrin glucanotransferase by use of modified maltooligosaccharides. | The active site of Bacillus macerans cyclodextrin glucanotransferase (CGTase) was examined by use of derivatives of phenyl alpha-maltopentaoside and phenyl alpha-glucoside as the substrates and acceptors, respectively. The active site of this enzyme is considered to be composed of tandem subsites (S4, S3, S2, S1, S1', ... |
1774251 | Identification of mycobacteria by high-performance liquid chromatography. | Mycolic acids extracted from saponified mycobacterial cells were examined as p-bromophenacyl esters by high-performance liquid chromatography (HPLC). Standard HPLC patterns were developed for species of Mycobacterium by examination of strains from culture collections and other well-characterized isolates. Relative rete... |
1767778 | [Two cases of traumatic bladder rupture with multiple organ failure]. | We report two cases of traumatic bladder rupture complicated by multiple organ failure (MOF). The first patient had an extraperitoneal bladder rupture and right femoral bone fracture, which were treated conservatively. However, intrapelvic abscess and adult respiratory distress syndrome (ARDS) which was caused by fat e... |
1760507 | pH-dependent structural transitions of Alzheimer amyloid peptides. | To understand the molecular interactions leading to the assembly of beta/44 protein into the hallmark fibrils of Alzheimer's disease (AD), we have examined the ability of synthetic peptides that correspond to the beta/A4 extracellular sequence to form fibrils over the range of pH 3-10. Peptides included the sequences 1... |
19431809 | Orienting rigid and flexible biological assemblies in ferrofluids for small-angle neutron scattering studies. | Small-angle scattering from macromolecules in solution is widely used to study their structures, but the information content is limited because the molecules are generally randomly oriented and hence the data are spherically averaged. The use of oriented rodlike structures for scattering, as in fiber diffraction, great... |
18965305 | Thermodynamic study of solvent extraction of 15-crown-5- and 18-crown-6-s-block metal ion complexes and tetraalkylammonium ions with picrate anions into chloroform. | Enthalpy and entropy changes for ion-pair extractions of tetraalkylammonium ions (R(4)N(+)) with picrate anions, overall extractions of s-block metal picrates with 15-crown-5 (15C5) and 18-crown-6 (18C6) and the partition of 15C5 itself were determined between chloroform and water. The distribution behaviour of crown e... |
18965304 | Chromogenic benzo- and monoaza-12-crown-4, 13-crown-4 and 14-crown-4 lithium-selective crown ethers. | Chromogenic benzo-12-crown-4, benzo-13-crown-4 and benzo-14-crown-4 ethers have been compared with monoaza-12-crown-4 and monoazal-13-crown-4 ethers. Of these compounds, monoaza-13-crown-4 exhibited the best analytical characteristics toward the selective determination of lithium. K(ex)Li/K(ex)Na was 525 for the monoaz... |
1840640 | Cloning and sequence analysis of genes involved in erythromycin biosynthesis in Saccharopolyspora erythraea: sequence similarities between EryG and a family of S-adenosylmethionine-dependent methyltransferases. | The gene cluster (ery) responsible for production of the macrolide antibiotic erythromycin by Saccharopolyspora erythraea is also known to contain ermE, the gene conferring resistance to the antibiotic. The nucleotide sequence has been determined of a 4.5 kb portion of the biosynthetic gene cluster, from a region lying... |
1741756 | Comparison of the domain-level organization of starch hydrolases and related enzymes. | Structure-prediction and hydrophobic-cluster analysis of several starch hydrolases and related enzymes indicated the organization of eleven domain types. Most enzymes possess a catalytic (beta/alpha)8-barrel and a smaller C-terminal domain as seen in crystal structures of alpha-amylase and cyclodextrin glucanotransfera... |
1660263 | The interaction of methanol dehydrogenase and cytochrome cL in the acidophilic methylotroph Acetobacter methanolicus. | The quinoprotein methanol dehydrogenase (MDH) of Acetobacter methanolicus has an alpha 2 beta 2 structure. By contrast with other MDHs, the beta-subunit (approx. 8.5 kDa) does not contain the five lysine residues previously proposed to be involved in ionic interactions with the electron acceptor cytochrome cL. That ele... |
1962191 | Molecular self-assembly and nanochemistry: a chemical strategy for the synthesis of nanostructures. | Molecular self-assembly is the spontaneous association of molecules under equilibrium conditions into stable, structurally well-defined aggregates joined by noncovalent bonds. Molecular self-assembly is ubiquitous in biological systems and underlies the formation of a wide variety of complex biological structures. Unde... |
1956772 | Mutagenesis of the DNA binding residues in bovine pancreatic DNase 1: an investigation into the mechanism of sequence discrimination by a sequence selective nuclease. | The sequence selectivity of DNase 1 cleavage has been investigated by site-directed mutagenesis of a chemically synthesised gene. Two key DNA binding residues have been conservatively altered (Y76F and R41K) or have had their side-chains truncated (Y76A and R41A) and the effect on the cleavage of tyr T promoter DNA has... |
1955467 | Russell bodies: a general response of secretory cells to synthesis of a mutant immunoglobulin which can neither exit from, nor be degraded in, the endoplasmic reticulum. | Dilated cisternae of the ER resembling Russell Bodies (RBs) are induced in light (L) chain producing myeloma cell lines by transfection of a mu heavy (H) chain gene lacking the first constant domain (mu delta CH1). RBs do not appear to be tissue specific, since they are also induced in a rat glioma cell line transfecte... |
1955460 | Elevated extracellular calcium concentrations induce type X collagen synthesis in chondrocyte cultures. | Chondrocytes at different stages of cellular differentiation were isolated from the tarsal element (immature chondrocytes) and zones 2 and 3 (mature chondrocytes) of 12-d chick embryo tibiotarsus. The chondrocytes from the two sources differed in their cell morphologies, growth rate and production of type X collagen. I... |
1955458 | Synthetic peptides from the carboxy-terminal globular domain of the A chain of laminin: their ability to promote cell adhesion and neurite outgrowth, and interact with heparin and the beta 1 integrin subunit. | The large carboxy-terminal globular domain (G domain; residues 2,110-3,060) of the A chain of murine-derived laminin has been shown to promote heparin binding, cell adhesion, and neurite outgrowth. This study was conducted to define the potential sequence(s) originating from the G domain of laminin with any of these fu... |
1953683 | A polyclonal antibody preparation with Michaelian catalytic properties. | 1. 4-Nitrophenyl 4'-(3-aza-2-oxoheptyl)phenyl carbonate (I), an amide conjugate (XI) involving the carboxy group of 4-nitrophenyl 4'-carboxymethylphenyl phosphate and an amino group of keyhole-limpet haemocyanin, and a fluorescein derivative (XVII) were synthesized. 2. The conjugate (XI) was used as an immunogen with w... |
1953667 | Substitution of cysteine for glycine-alpha 1-691 in the pro alpha 1(I) chain of type I procollagen in a proband with lethal osteogenesis imperfecta destabilizes the triple helix at a site C-terminal to the substitution. | Skin fibroblasts from a proband with lethal osteogenesis imperfecta synthesized a type I procollagen containing a cysteine residue in the alpha 1(I) helical domain. Assay of thermal stability of the triple helix by proteinase digestion demonstrated a decreased temperature for thermal unfolding of the protein. Of specia... |
1946376 | Escape from transforming growth factor beta control and oncogene cooperation in skin tumor development. | Control of tumor development by surrounding normal cells has been suggested by a number of in vitro studies. In vivo, tumorigenicity of ras-transformed primary keratinocytes can be suppressed by addition of normal dermal fibroblasts. Here, we report that dermal fibroblasts produce a diffusible inhibitory factor belongi... |
1834996 | The N-terminal part of the E.coli DNA binding protein FIS is essential for stimulating site-specific DNA inversion but is not required for specific DNA binding. | FIS protein is involved in several different cellular processes stimulating site-specific recombination in phages Mu and lambda as well as transcription of stable RNA operons in E.coli. We have performed a mutational analysis of fis and provide genetic and biochemical evidence that a truncated version of FIS lacking th... |
1945874 | Solid phase synthesis of oligodeoxyribonucleoside phosphorodithioates from thiophosphoramidites. | Oligonucleoside phosphorodithioates 1 are modified DNA sequences with potential use as antisense oligonucleotides. The preparation of up to 20-mers containing all four bases by solid phase synthesis is described, with details on the preparation of the four monomer units (protected nucleoside thiophosphoramidites 2), th... |
1658746 | DNA-sequence specific recognition by a thiazole analogue of netropsin: a comparative footprinting study. | Four different footprinting techniques have been used to probe the DNA sequence selectivity of Thia-Net, a bis-cationic analogue of the minor groove binder netropsin in which the N-methylpyrrole moieties are replaced by thiazole groups. In Thia-Net the ring nitrogen atoms are directed into the minor groove where they c... |
1941102 | Association of heparan sulfate proteoglycan with the neurofibrillary tangles of Alzheimer's disease. | The major intracytoplasmic lesion of Alzheimer's disease is the neurofibrillary tangle (NFT), which is primarily composed of paired helical filaments (PHFs). The mechanism responsible for the formation of PHFs, as well as their insolubility and apparent heterogeneity, is unknown. We found that basic fibroblast growth f... |
1834700 | Mithramycin inhibits SP1 binding and selectively inhibits transcriptional activity of the dihydrofolate reductase gene in vitro and in vivo. | The promoter of the human dihydrofolate reductase (DHFR) gene contains two consensus binding sites for the DNA binding protein Sp1. DNAse protection and gel mobility shift assays demonstrate binding of recombinant Sp1 to both decanucleotide Sp1 binding sequences which are located 49 and 14 base pairs upstream of the tr... |
1939274 | Agonist binding site of Torpedo electric tissue nicotinic acetylcholine receptor. A negatively charged region of the delta subunit within 0.9 nm of the alpha subunit binding site disulfide. | The positively charged quaternary ammonium group of agonists of the nicotinic acetylcholine (ACh) receptor binds to a negative subsite at most about 1 nm from a readily reducible disulfide. This disulfide is formed by alpha Cys192 and Cys193 (Kao and Karlin, 1986). In order to identify Asp or Glu residues that may cont... |
1834654 | Key enzymes of carbohydrate metabolism as targets of the 11.5-kDa Zn(2+)-binding protein (parathymosin). | The 11.5-kDa Zn(2+)-binding protein (ZnBP) was covalently linked to Sepharose. Affinity chromatography with a cytosolic subfraction from liver resulted in purification of a predominant 38-kDa protein. In comparable experiments with brain cytosol a 39-kDa protein was enriched. The ZnBP-protein interactions were zinc-spe... |
1938915 | Effects of glucosamine on lysis, glycerol formation, and sporulation in Myxococcus xanthus. | Glucosamine (GlcN), which has previously been shown to rescue fruiting body formation, lysis, and sporulation in a developmental mutant (G. Janssen and M. Dworkin, Dev. Biol. 112:194-202, 1985), induced lysis in vegetative and developing wild-type cells and inhibited fruiting body formation. It also resulted in a trans... |
1938907 | Nucleotide sequence and expression analysis of the Acetobacter xylinum uridine diphosphoglucose pyrophosphorylase gene. | The nucleotide sequence of the Acetobacter xylinum uridine diphosphoglucose pyrophosphorylase gene was determined; this is the first procaryotic uridine diphosphoglucose pyrophosphorylase gene sequence reported. The sequence data indicated that the gene product consists of 284 amino acids. This finding was consistent w... |
1938891 | Role of the S layer in morphogenesis and cell division of the archaebacterium Methanocorpusculum sinense. | Thin sections, freeze-etched, and negatively stained preparations of Methanocorpusculum sinense cells reveal a highly lobed cell structure with a hexagonally arranged surface layer (S layer). Digital image processing of negatively stained envelope fragments show that the S layer forms a porous but strongly interconnect... |
1657867 | The Bradyrhizobium japonicum cycM gene encodes a membrane-anchored homolog of mitochondrial cytochrome c. | Mitochondrial cytochrome c is a water-soluble protein in the intermembrane space which catalyzes electron transfer from the cytochrome bc1 complex to the terminal oxidase cytochrome aa3. In Bradyrhizobium japonicum, a gene (cycM) which apparently encodes a membrane-anchored homolog of mitochondrial cytochrome c was dis... |
1718941 | A development-specific protein in Myxococcus xanthus is associated with the extracellular fibrils. | We have been using monoclonal antibodies (MAbs) as probes to study developmentally relevant cell surface antigens (CSA) that may be required for cellular interactions in Myxococcus xanthus. Three independently isolated MAbs, G69, G357, and G645, isolated by Gill and Dworkin recognize a CSA detectable only on developing... |
1938880 | Characterization of the Butyrivibrio fibrisolvens glgB gene, which encodes a glycogen-branching enzyme with starch-clearing activity. | A Butyrivibrio fibrisolvens H17c glgB gene, was isolated by direct selection for colonies that produced clearing on starch azure plates. The gene was expressed in Escherichia coli from its own promoter. The glgB gene consisted of an open reading frame of 1,920 bp encoding a protein of 639 amino acids (calculated Mr, 73... |
1682257 | Construction of minitransposons for constitutive and inducible expression of pertussis toxin in bvg-negative Bordetella bronchiseptica. | Appropriately detoxified pertussis toxin (PT) of Bordetella pertussis is considered to be an essential component of new-generation whooping cough vaccines, but the development of a procedure to obtain high levels of purified toxin has been and continues to be a major difficulty. To produce a system enabling the biologi... |
1937757 | Identification and purification of transferrin- and lactoferrin-binding proteins of Bordetella pertussis and Bordetella bronchiseptica. | Bordetella pertussis and Bordetella bronchiseptica were both able to grow in iron-deficient medium when supplemented with iron-saturated human lactoferrin or transferrin but not with human apotransferrin. Direct contact between the transferrins and the Bordetella cells did not appear to be required for growth but consi... |
1937749 | Intramacrophagic Mycobacterium avium bacilli are coated by a multiple lamellar structure: freeze fracture analysis of infected mouse liver. | We used freeze fracture electron microscopy to study the fine structure of Mycobacterium avium inside phagosomes of murine macrophages. M. avium-susceptible C57BL/6 mice were infected with M. avium by intraperitoneal inoculation of 10(8) viable bacilli. We studied the microanatomy of the mycobacteria in 3-month infecti... |
1931991 | Design of a small peptide-based proteinase inhibitor by modeling the active-site region of barley chymotrypsin inhibitor 2. | A synthetic peptide-based proteinase inhibitor was constructed by modeling the regions responsible for inhibition in barley chymotrypsin inhibitor 2 (CI-2). The 18-residue peptide was designed by molecular modeling, based on the crystal structure of CI-2. The amino acid sequences that interact with the proteinase were ... |
1931615 | Tumour localisation with a radioactively labelled reshaped human monoclonal antibody. | A genetically reshaped human IgG1 monoclonal antibody (Hu2PLAP) with anti-tumour specificity, was radiolabelled with Indium-111 by chelation with a new macrocyclic compound (DOTA) which allows the production of stable radioimmunoconjugates for in vivo application. This was used to image seven patients with malignant di... |
1931602 | Photocytotoxic efficacy of sulphonated species of aluminium phthalocyanine against cell monolayers, multicellular spheroids and in vivo tumours. | The problem of relying solely on in vitro data to predict photosensitiser efficacy was demonstrated by examining the uptake and the ability to mediate photocytotoxicity of mono-, di-, tri- and tetra-sulphonated species of chloroaluminium phthalocyanine (AlS1-4Pc) in monolayer cultures of murine Colo 26 cells and in bot... |
1922065 | The CDC20 gene product of Saccharomyces cerevisiae, a beta-transducin homolog, is required for a subset of microtubule-dependent cellular processes. | Previous analysis of cdc20 mutants of the yeast Saccharomyces cerevisiae suggests that the CDC20 gene product (Cdc20p) is required for two microtubule-dependent processes, nuclear movements prior to anaphase and chromosome separation. Here we report that cdc20 mutants are defective for a third microtubule-mediated even... |
1920633 | Assembly of nucleocapsidlike structures in animal cells infected with a vaccinia virus recombinant encoding the measles virus nucleoprotein. | A vaccinia virus recombinant containing the measles virus nucleoprotein gene was shown to induce the synthesis of a 60 kDa phosphorylated nucleoprotein similar to authentic measles virus nucleoprotein. Mammalian or avian cells infected with the recombinant virus displayed tubular structures reminiscent of viral nucleoc... |
1717717 | Characterization of a discontinuous human immunodeficiency virus type 1 gp120 epitope recognized by a broadly reactive neutralizing human monoclonal antibody. | While one hypervariable, linear neutralizing determinant on the human immunodeficiency virus type 1 (HIV-1) gp120 envelope glycoprotein has been well characterized, little is known about the conserved, discontinuous gp120 epitopes recognized by neutralizing antibodies in infected individuals. Here, the epitope recogniz... |
1655422 | Resolvase-catalysed reactions between res sites differing in the central dinucleotide of subsite I. | The resolvase-catalysed reaction between two res sites in a circular DNA substrate normally gives two circular recombination products linked in a two-noded catenane. Homology between the two res sites at the central overlap dinucleotide of subsite I is important for recombination. Reactions between res sites differing ... |
1915306 | Substrate specificity of the dsRNA unwinding/modifying activity. | Double-stranded RNA (dsRNA) unwinding/modifying activity, which is present in a wide range of eukaryotic cells, has been previously shown to convert up to 50% of adenosine residues to inosines within intermolecular dsRNA. In the present study, we report that this activity also modifies, though slightly less efficiently... |
1717261 | Recombinant nidogen consists of three globular domains and mediates binding of laminin to collagen type IV. | Recombinant mouse nidogen and two fragments were produced in mammalian cells and purified from culture medium without resorting to denaturing conditions. The truncated products were fragments Nd-I (positions 1-905) comprising the N-terminal globule and rod-like domain and Nd-II corresponding mainly to the C-terminal gl... |
1840094 | DNA interpolyelectrolyte complexes as a tool for efficient cell transformation. | A tool was developed for enhancement of plasmid penetration into an intact cell, based on increasing DNA hydrophobicity via inclusion into a soluble interpolyelectrolyte complex (IPC) with polycations. The characteristics of formation of DNA IPC with synthetic polycations [poly(N-ethyl-4-vinylpyridinium)bromide (PVP) a... |
1815912 | [Effect of total parenteral nutrition with different nitrogen burden on organ function and protein metabolism in multiple organ failure rabbits]. | Rabbits with MOF induced by intraabdominal sepsis were used to observe the effect of TPN with different amount of amino acid nitrogen on organ function, nitrogen balance and urine 3-MH excretion. The results showed that TPN support could improve the impaired organ function and reverse negative nitrogen balance. Low nit... |
1812279 | [Improvement of stability and bioavailability of 1-hexylcarbamoyl-5-fluorouracil (HCFU) by O-carboxymethyl-O-ethyl-beta- cyclodextrin]. | The possible utility of O-carboxymethyl-O-ethyl-beta-cyclodextrin (CME-beta-CyD) as a novel drug carrier was studied in vitro and in vivo, by using 1-hexylcarbamoyl-5-fluorouracil (HCFU) as a model drug. The chemical instability of HCFU in solution and solid state was improved by CME-beta-CyD complexation. The in vitro... |
1806294 | Optical separation of racemic 5-(p-hydroxyphenyl)-5-phenylhydantoin by reversed phase high-performance liquid chromatography using eluents containing beta-cyclodextrin. | Both S-(-)- and R-(+)-enantiomers of 5-(p-hydroxyphenyl)-5-phenylhydantoin (p-HPPH), a main oxidative metabolite of the achiral antiepileptic drug phenytoin, could be determined simply, sensitively and accurately using reversed phase high-performance liquid chromatography by using a methanol-monopotassium phosphate elu... |
1805456 | Nucleophilic addition to the ethynyl group in ethynylestradiol catalyzed by crown ether-copper (1) iodide. | A new and convenient synthetic route to acetylation of estrogens is described. Benzo-15-crown-5 and cuprous iodide-mixed catalyst catalyzed the nucleophilic addition of 2,4-dibromoethynylestradiol, resulting in the formation of a new compound, 2,4-dibromo-17 alpha-acetylestradiol, of which the structure was characteriz... |
1799430 | [Evaluation of beta-cyclodextrins as formulated coadjuvants for improved drug solubility]. | Cyclodextrins are known to form inclusion complexes in acqueous solutions with various types of organic substance, also a lot of hydrophobic drugs. Drugs/beta CD complexes obtained applying different techniques, eventually in solid state, usually show an improvement of solubility or at last in dissolution characteristi... |
1796053 | Chemical stabilization of a vasoactive S-nitrosothiol with cyclodextrins without loss of pharmacologic activity. | S-Nitrosothiols have been proposed as the endogenous chemical representing the vasoactive endothelium-derived relaxing factor, as well as the active cellular intermediates responsible for the therapeutic action of organic nitrates. The relatively stable analogue S-nitroso N-acetyl penicillamine (SNAP) is a potent vasod... |
1796050 | Structural effects on the binding of amine drugs with the diphenylmethyl functionality to cyclodextrins. II. A molecular modeling study. | Molecular modeling has been used to study the complexation between alpha, beta, or gamma-cyclodextrin (CD) and a group of amine compounds having the diphenylmethyl functionality. The computer program SYBYL 5.3 and the Tripos force field (version 5.2) were used for all the calculations. Three-dimensional structures of 1... |
1370622 | Production of cyclodextrins, a novel carbohydrate, in the tubers of transgenic potato plants. | Cyclodextrins (CDs) are cyclic oligosaccharides containing six (alpha), seven (beta), or eight (gamma) glucose molecules, respectively. The cyclodextrin glycosyltransferases (CGT), which produce CDs from starch, are found only in bacteria and are used in batch fermentors with hydrolyzed starch to produce CDs commercial... |
1761623 | Selected applications of cyclodextrin selectors in capillary electrophoresis. | Through the use of alpha-, beta-, gamma- and heptakis(2,6-di-O-methyl)-beta-cyclodextrin as stereospecific selectors or electrolyte modifiers, both in capillary zone electrophoresis and isotachophoresis, selected model isomeric compounds (including optical isomers) were resolved. Soluble alkylhydroxyalkylcellulose deri... |
1759816 | Borderline susceptibility to antistaphylococcal penicillins is not conferred exclusively by the hyperproduction of beta-lactamase. | Staphylococcus aureus strains bearing the 17.2-kb beta-lactamase plasmid pBW15 and belonging to phage group 94/96 exhibit borderline susceptibility to the antistaphylococcal penicillins. Borderline susceptibility within phage group 94/96 is thought to be mediated by the hyperproduction of type A staphylococcal beta-lac... |
1757986 | A strategy for the reconstruction of structures possessing axial symmetry: sectioned axonemes in sperm flagella. | The images of complex biological structures seen in the electron microscope, possessing an n-fold rotational symmetry, can be enhanced by averaging the axially repeating motif in order to improve their signal-to-noise ratio; this requires that the slices with n-fold symmetry do not exhibit distortions relative to one a... |
1757799 | Arabinitol enantiomers in cerebrospinal fluid. | D-Arabinitol is a metabolite of Candida species, and its presence in serum above endogenous concentration may indicate disseminated candidiasis. The o-trifluoroacetylated derivatives of arabinitol enantiomers in cerebrospinal fluid (CSF) were separated using perpentylated cyclodextrin capillary columns and measured by ... |
24233927 | Separation of selected PAHs by using high performance capillary electrophoresis with modifiers. | The effect of varying SDS concentration in a micellar electrokinetic capillary chromatographic system (MECC) is investigated. In addition, the introduction of γ-cyclodextrin as modifier to the electrophoretic medium, containing SDS and a phosphate-borate buffer, is shown to give satisfactory separation of the seven sel... |
24194170 | The chemistry of natural enzyme-induced cross-links of proteins. | The cross-linking of protein molecules to form stable supramolecular aggregates capable of acting as protective and supporting structures is a common feature of organisms coping with the stresses of life. These new polymeric forms range from thick rigid structures to thin flexible membranes. The formation of such cross... |
1747214 | Rapid smooth muscle cell growth and endogenous prostaglandin system in spontaneously hypertensive rats. | Vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) exhibit rapid cell growth. In this study, to reveal the mechanisms of the quick VSMC growth, we analyzed the alterations in the respective periods of the proliferating cell cycle, and investigated the role of the endogenous prostaglandin sys... |
1957176 | [Liver failure as part of multiple organ failure following polytrauma]. | In the last few years there has been increasing evidence that adult respiratory distress syndrome is only part of a much more complex syndrome called multiorgan failure (MOF). Since renal and lung failure have become rare because of our increased understanding of the pathomechanisms involved and the treatment changes, ... |
1957174 | [Multiple organ failure. Reflection of generalized cell damage of all organs following severe trauma]. | Multiple organ failure (MOF) is presently recognized as the most severe, and often lethal, complication after multiple trauma. Causal factors and pathomechanisms remain unclear, however. Generalized inflammatory cell tissue injury with a subsequent increase in permeability in all organs has been suggested. For this rea... |
1949039 | DNA cross-linking in mammalian cells by pyrrolizidine alkaloids: structure-activity relationships. | Pyrrolizidine alkaloids (PAs) are common constituents of many species of flowering plants which possess carcinogenic as well as anticarcinogenic activity in vivo. Pyrrolizidine alkaloids are genotoxic in various short-term assays. The mechanisms by which these compounds exert these effects is still unclear. In this stu... |
1949027 | Application of molecular encapsulation for toxicology studies: toxicokinetics of p-chloro-alpha,alpha,alpha-trifluorotoluene in alpha-cyclodextrin or corn oil vehicles in male F344 rats. | Toxicokinetics of p-chloro-alpha,alpha,alpha-trifluorotoluene (CTFT) after administration as an aqueous alpha-cyclodextrin (alpha-CD) molecular encapsulation suspension (alpha-CD vehicle) or as a corn oil solution (corn oil vehicle) were compared. Male F344 rats were administered intragastrically CTFT in alpha-CD vehic... |
1945848 | A Drosophila Adh gene can be activated in trans by an enhancer. | The ability of a segment of the Drosophila Adh gene to produce ADH activity in larvae is dependent upon the presence of a 53 bp sequence (called NS1) located between 289 and 341 bp upstream of the larval transcription start site. This sequence behaves like an enhancer in that it can stimulate gene activity when it is p... |
1942062 | Role of the disordered terminal regions of flagellin in filament formation and stability. | Terminal regions of flagellin from Salmonella typhimurium, residues 1 to 65 and 451 to 494, have no ordered tertiary structure in solution, which makes them very susceptible to proteolytic degradation. Flagellin was subjected to mild controlled proteolytic treatment with highly specific proteases to remove terminal seg... |
1658336 | Model for the interaction of DNA junctions and resolving enzymes. | Four-way DNA junctions are thought to be important intermediates in a number of recombination processes. Resolution of these junctions occurs by cleavage of two strands of DNA to generate two duplex molecules. The interaction between DNA junctions and resolving enzymes appears to be largely structure-specific, reflecti... |
1658334 | DNA-bending properties of TF1. | Transcription factor 1 (TF1) is the Bacillus subtilis phage SPO1-encoded member of the family of DNA-binding proteins that includes Escherichia coli HU and integration host factor, IHF. A gel electrophoretic retardation method has been used to show that a TF1 dimer binding to one of its preferred sites in (5-hydroxymet... |
1658008 | Glucose induces lipid peroxidation and inactivation of membrane-associated ion-transport enzymes in human erythrocytes in vivo and in vitro. | Erythrocytes of diabetic subjects (non-insulin dependent) were found to have eight- to ten-fold higher levels of endogenously formed thiobarbituric acid reactive malonyldialdehyde (MDA), thirteen-fold higher levels of phospholipid-MDA adduct, 15-20% reduced Na(+)-K(+)-ATPase activity with unchanged Ca+2-ATPase activity... |
1656969 | An ATP-independent catenating enzyme from the kinetoplast hemoflagellate Leishmania donovani. | An enzyme from Leishmania donovani that catenates monomeric pBR322 into huge catenanes has been isolated and characterized. The enzyme also decatenates kinetoplast DNA networks into covalently closed monomeric circles and relaxes supercoiled pBR322. The catenation, decatenation and relaxation reactions do not require A... |
1928300 | Renal disease in carrier female dogs with X-linked hereditary nephritis. Implications for female patients with this disease. | Male dogs with X-linked hereditary nephritis (HN) serve as a model for studying male patients with this disease. In the present study, carrier female dogs were found to resemble female patients in showing a broad range of renal dysfunction. Of 37 carrier female dogs studied, all were healthy up to 5 years of age; howev... |
1924396 | Propeptide of carboxypeptidase Y provides a chaperone-like function as well as inhibition of the enzymatic activity. | The zymogen of the vacuolar carboxypeptidase Y from Saccharomyces cerevisiae was purified and characterized with respect to activation as well as refolding in vitro. The purified procarboxypeptidase Y has no detectable activity but can be efficiently activated by proteinase K from Tritirachium album. We used this metho... |
1924393 | Monoclonal antibody-targeted superantigens: a different class of anti-tumor agents. | The bacterial superantigen staphylococcal enterotoxin (SE) A (SEA) directs cytotoxic T lymphocytes (CTLs) expressing particular sequences of the T-cell receptor (TCR) beta chain to lyse tumor cells expressing major histocompatibility complex (MHC) class II molecules, which serve as receptors for SEs. We now report that... |
1924382 | Alanine scanning site-directed mutagenesis of the zinc fingers of transcription factor ADR1: residues that contact DNA and that transactivate. | To identify functionally important amino acids in the two zinc fingers of transcription factor ADR1 [alcohol dehydrogenase (ADH) II synthesis regulator], oligonucleotide-directed mutagenesis was used to substitute alanine for the original amino acid at each position in both fingers. The effects of these mutations on DN... |
1924378 | Electrostatic control of midpoint potentials in the cytochrome subunit of the Rhodopseudomonas viridis reaction center. | The photosynthetic reaction center of Rhodopseudomonas viridis has four hemes in a linear arrangement with alternating high- and low-potential sites. Their midpoints are -60, 20, 310, and 380 mV [Dracheva, S. M., Drachev, L. A., Konstantinov, A. A., Semenov, A. Y., Skulachev, V. P., Arutjunjan, A. M., Shuvalov, V. A. &... |
1833770 | Identification of the Fc gamma receptor class I binding site in human IgG through the use of recombinant IgG1/IgG2 hybrid and point-mutated antibodies. | To characterize the region on human IgG1 responsible for its high-affinity interaction with the human Fc gamma receptor class I (Fc gamma RI), we have analyzed the binding properties of a series of genetically engineered chimeric antidinitrophenyl antibodies with identical murine antibody combining sites and hybrid IgG... |
1681543 | Molecular cloning of a putative receptor protein kinase gene encoded at the self-incompatibility locus of Brassica oleracea. | Self-recognition between pollen and stigma during pollination in Brassica oleracea is genetically controlled by the multiallelic self-incompatibility locus (S). We describe the S receptor kinase (SRK) gene, a previously uncharacterized gene that resides at the S locus. The nucleotide sequences of genomic DNA and of cDN... |
1924337 | Engineering the substrate specificity of glutathione reductase toward that of trypanothione reduction. | Glutathione reductase (EC 1.6.4.2; CAS registry number 9001-48-3) and trypanothione reductase (CAS registry number 102210-35-5), which are related flavoprotein disulfide oxidoreductases, have marked specificities for glutathione and trypanothione, respectively. A combination of primary sequence alignments and molecular... |
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