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4032005 | gamma-Aminobutyric acid- and benzodiazepine-induced modulation of [35S]-t-butylbicyclophosphorothionate binding to cerebellar granule cells. | t-Butylbicyclophosphorothionate (TBPS) is a bicyclophosphate derivative with potent picrotoxin-like convulsant activity that binds with high affinity and specificity to a Cl- channel-modulatory site of the gamma-aminobutyric acid (GABA)/benzodiazepine receptor complex. Using intact cerebellar granule cells maintained i... |
3897249 | Purification of the 300K intermediate filament-associated protein and its in vitro recombination with intermediate filaments. | IFAP-300K is a 300,000-mol-wt intermediate filament-associated protein previously identified in the baby hamster kidney fibroblastic cell line (BHK-21) by a monoclonal antibody (Yang H.-Y., N. Lieska, A. E. Goldman, and R. D. Goldman, 1985, J. Cell Biol., 100: 620-631). In the present study, this molecule was purified ... |
3897064 | An in vitro ultrastructural study of infectious kidney stone genesis. | A ureolytic strain of Proteus mirabilis, isolated from a patient with infectious kidney stones, produced struvite (MgNH4PO4 X 6 H2O) and apatite [Ca10(PO4)6CO3] crystals in vitro when grown in artificial urine. Surface-attached crystals were encased in a slime-like layer. Scanning electron microscopy revealed that surf... |
4029608 | Fine structure and instability of the Ml-a locus in barley. | There are many naturally occurring variants at the Ml-a locus in barley that confer resistance to the powdery mildew fungus Erysiphe graminis f. sp. hordei. Since the Ml-a locus is bracketed by Hor-1 and Hor-2, genes that encode storage proteins in the endosperm, the Ml-a locus is amenable to fine structure analysis. R... |
15938051 | Correlation between structure and pathogenicity of potato spindle tuber viroid (PSTV). | Sequence analysis by primer-extension at the level of their cDNA showed that the RNA genomes of various field isolates of potato spindle tuber viroid (PSTV) of different virulence differ from each other only in a few nucleotides in two distinct regions of the rod-shaped molecule. Despite insertions and deletions the ch... |
3018548 | Replication and supercoiling of simian virus 40 DNA in cell extracts from human cells. | Soluble extracts prepared from the nucleus and cytoplasm of human 293 cells are capable of efficient replication and supercoiling of added DNA templates that contain the origin of simian virus 40 replication. Extracts prepared from human HeLa cells are less active than similarly prepared extracts from 293 cells for ini... |
2998784 | Definition of three resolvase binding sites at the res loci of Tn21 and Tn1721. | The dual functions of resolvase, site-specific recombination and the regulation of its own expression from tnpR, both require the interaction of this protein with the DNA sequence at res, but the specificity of this interaction differs between groups of Tn3-like elements. In this study, DNA fragments that contained res... |
2998783 | Inhibition of calf thymus type II DNA topoisomerase by poly(ADP-ribosylation). | The effect of poly(ADP-ribosylation) on calf thymus topoisomerase type II reactions has been investigated. Unknotting of phage P4 head DNA, and relaxation and catenation of supercoiled PM2 DNA are inhibited. We conclude that the inhibition results from poly(ADP-ribosylation) on the following grounds. Firstly, the enzym... |
4052030 | Interactions with glutathione S-transferases of porphyrins used in photodynamic therapy and naturally occurring porphyrins. | Several naturally occurring porphyrins and porphyrins used in photodynamic therapy inhibit glutathione S-transferase isoenzymes either purified from rat liver or lung or in cytosol from normal and from cancerous (Morris 7288C hepatoma) liver. Although differences occur in the type and amount of transferases in normal a... |
3901351 | Special problems in the diagnosis and treatment of surgical sepsis. | Since sepsis is the most frequent single cause of death after surgery and trauma, its development should be anticipated in elderly patients or those with disease or trauma causing intestinal leaks, particularly if the patient had massive transfusions or was in shock. Diagnosis may be extremely difficult, particularly i... |
2864411 | Improvement in the percutaneous absorption of beclomethasone dipropionate by gamma-cyclodextrin complexation. | Inclusion complex formation of beclomethasone dipropionate (BMDP) with gamma-cyclodextrin (gamma-CyD) in water and in solid state was assessed by solubility analysis and X-ray diffractometry. The solid complex of BMDP with gamma-CyD in a molar ratio of 1:2 was prepared and its in-vitro release behaviour was investigate... |
4032267 | Improvement of dissolution and suppository release characteristics of flurbiprofen by inclusion complexation with heptakis(2,6-di-O-methyl)-beta-cyclodextrin. | The inclusion behavior of methylated beta-cyclodextrins, heptakis(2,6-di-O-methyl)-beta-cyclodextrin and heptakis-(2,3,6-tri-O-methyl)-beta-cyclodextrin in solution and the solid state was compared with that of natural beta-cyclodextrin using an anti-inflammatory drug, flurbiprofen, as a guest molecule. Stability const... |
3928700 | Distribution of fibronectin and laminin in normal and pathological lymphoid tissue. | Forty six lymph nodes were examined with the indirect immunoperoxidase technique for the distribution of fibronectin and laminin. Fibronectin was present in the framework of the tissue and the basal lamina of blood vessels, giving a clear outline of nodal architecture. Intracellular fibronectin was observed in cases of... |
3897290 | Acute intermittent porphyria: characterization of a novel mutation in the structural gene for porphobilinogen deaminase. Demonstration of noncatalytic enzyme intermediates stabilized by bound substrate. | To investigate the molecular pathology in acute intermittent porphyria (AIP), the nature of the defective porphobilinogen (PBG)-deaminase was determined in erythrocyte lysates from 165 AIP heterozygotes from 92 unrelated families representing 20 different ethnic or demographic groups. Immunologic and physicokinetic stu... |
4031061 | Antiadhesive properties of biological surfaces are protective against stimulated granulocytes. | Despite the fact that a series of endogenous and exogenous inflammatory mediators are potent activators of circulating granulocytes, damage of vascular endothelium, a primary target tissue, is a rather unusual event in systemic inflammatory states. Since mediator-induced neutrophil hyperadhesiveness on plastic tissue c... |
3928029 | Genetic heterogeneity in acute intermittent porphyria: characterisation and frequency of porphobilinogen deaminase mutations in Finland. | The occurrence of different porphobilinogen deaminase mutant types in 68 patients with acute intermittent porphyria from 33 unrelated families in Finland was studied with biochemical and immunological techniques. In this fairly homogenous population four different porphobilinogen deaminase mutant types were identified ... |
4026077 | Elevated pulmonary vascular resistance in patients dying from multiple organ failure. | Twenty-one patients with multiple organ failure were studied with hemodynamic monitoring. The five survivors were compared with the 16 nonsurvivors. Significant differences were found in the cardiac index (CI), the left ventricular stroke work index (LVSWI), and the pulmonary vascular resistance index (PVRI). The CI wa... |
3927298 | Molecular cloning of Lyt-2, a membrane glycoprotein marking a subset of mouse T lymphocytes: molecular homology to its human counterpart, Leu-2/T8, and to immunoglobulin variable regions. | The sequence of Lyt-2 cDNA shows that it is a new member of the immunoglobulin super gene family. Analysis of the predicted amino acid sequence indicates that the Lyt-2 polypeptide is synthesized with a 27-amino acid leader, and that the mature protein has an immunoglobulin variable region (Ig V)-related sequence of ap... |
4019582 | Abrogation of cell surface expression of human class I transplantation antigens by an adenovirus protein in Xenopus laevis oocytes. | Class I transplantation antigens form complexes with a virus protein encoded in the early region E3 of the adenovirus-2 genome. The interaction between this viral glycoprotein, E19, and nascent human class I antigens has been examined by microinjecting purified mRNA into Xenopus laevis oocytes. Both E19 and the two cla... |
3894376 | Intermediate filaments and the initiation of desmosome assembly. | The desmosome junction is an important component in the cohesion of epithelial cells, especially epidermal keratinocytes. To gain insight into the structure and function of desmosomes, their morphogenesis has been studied in a primary mouse epidermal (PME) cell culture system. When these cells are grown in approximatel... |
3926768 | On the structure of heme d1. An isobacteriochlorin derivative as the prosthetic group of dissimilatory nitrite reductase? | Timkovich and co-workers have recently proposed a chlorin macrocycle structure for the heme d1 prosthetic group isolated from cytochrome cd1 of Pseudomonas aeruginosa and Paracoccus denitrificans (Timkovich, R., Cork, M. S., and Taylor, P. V. (1984) J. Biol. Chem. 259, 1577-1585; 15089-15093). However, this chlorin str... |
3160481 | The stereostructure of knots and catenanes produced by phage lambda integrative recombination: implications for mechanism and DNA structure. | We studied the mechanism of recombination by determining the structure of the products of the phage lambda Int system. Electron microscopy of RecA-coated products revealed only knots and catenanes containing a regular right-handed spiral structure. The structure and distribution of products establish that the recombina... |
18963999 | Preparation and gas chromatographic characterization of some crown-ether stationary phases. | Three open tubular glass capillary Chromatographic columns containing poly(vinylbenzo-15-crown-5), vinylmethylsila-17-crown-6, and vinylmethylsila-14-crown-5 have been prepared and characterized. The silacrown-ether stationary phases were polymerized inside the capillary and copolymerized with a methacryloxysilane boun... |
18963988 | Effect of cyclodextrin cavity size on sensitization of room-temperature phosphorescence of biacetyl. | The triplet-triplet energy-transfer reactions of several polynuclear aromatic compounds are enhanced to different degrees in alpha -,beta and gamma-cyclodextrin (CD) media when biacetyl is used as the acceptor species. The phosphorescence intensity of biacetyl increases as the size of the CD cavity increases. The CD ca... |
18640546 | Characterization and localization of CIV polypeptides. | In order to detect the structural proteins linked with disulfide bonds, CIV was solubilized and electrophoresed under nonreducing conditions in the first dimension and then under reducing conditions in the second dimension. The viral polypeptides linked originally with disulfide bonds were separated into subunits. The ... |
3002497 | Molecular recognition in noncovalent antitumor agent-DNA complexes: NMR studies of the base and sequence dependent recognition of the DNA minor groove by netropsin. | We have investigated intermolecular interactions and conformational features of the netropsin complexes with d(G1-G2-A3-A4-T5-T6-C7-C8) duplex (AATT 8-mer) and the d(G1-G2-T3-A4-T5-A6-C7-C8) duplex (TATA 8-mer) by one and two-dimensional NMR studies in solution. We have assigned the amide, pyrrole and methylene protons... |
4052466 | [Effect of hydrogen ion concentration in the medium on the state of chromatin in lymphoid cells]. | Effect of medium acidity (pH 7.2 divided by 6.6) on the state of lymphoid tissue cells was studied by microspectrofluorimetry, electrophoresis and IR-spectroscopy. Two stages of the cell structural-functional changes were found at H2CO3 acidification of the medium. The first one is a reversible transition of chromatin ... |
2864667 | Action and localization of neuropeptide Y in the human fallopian tube. | Using indirect immunohistochemistry, neuropeptide Y-like immunoreactivity was found in nerve fibers around blood vessels and in the muscle layers of the human fallopian tube. Apart from a network of immunoreactive nerve fibers in connection with the luminary epithelium of the isthmus, the distribution resembled that of... |
4041240 | Stability and self-assembly of the S-layer protein of the cell wall of Bacillus stearothermophilus. | The surface layer of the cell envelope of Bacillus stearothermophilus consists of a regular array of protein subunits. As shown by dodecyl sulfate polyacrylamide gel-electrophoresis and ultracentrifugation, the fully solubilized S-layer protein represents a homogeneous entity with a subunit molecular mass of 115 +/- 5 ... |
3840018 | Primary structure of the telopeptide and a portion of the helical domain of chicken type II procollagen as determined by DNA sequence analysis. | A comparison of the nucleotide sequences of three new cDNA clones for chicken type II procollagen with the sequences of the other three types of chicken fibrillar procollagens reveals that the most conserved regions correlate with the positions of hydroxyproline, hydroxylysine, cysteine and lysine residues. On the basi... |
2863821 | The Bakerian lecture, 1984. Biosynthesis of the pigments of life. | Many vitally important functions in living systems are carried out by metal ions held as complexes within organic ligands, the organic part of the molecule being a tetrapyrrolic macrocycle. Chlorophyll, haemoglobin, the cytochromes and vitamin B12 all fall into this family of 'pigments of life', a list that emphasizes ... |
3875731 | Phage P1 Cre-loxP site-specific recombination. Effects of DNA supercoiling on catenation and knotting of recombinant products. | Bacteriophage P1 contains a site-specific recombination system consisting of a site, loxP, and a recombinase protein Cre. We have shown that with purified Cre protein we can carry out recombination between two loxP sites in vitro. When that recombination occurs between two sites in direct orientation on the same DNA mo... |
4030501 | Inclusion compounds of lankacidin-group antibiotics with cyclodextrins. | Lankacidin-group antibiotics formed inclusion compounds with beta-cyclodextrin in molar ratios of about 1:1. These compounds showed remarkably improved water-solubility and stability in aqueous solutions. The structure of the inclusion compounds of lankacidin A is proposed based on the facility of their inclusion with ... |
4026292 | Intestinal microbial flora after feeding phytohemagglutinin lectins (Phaseolus vulgaris) to rats. | Incorporation of purified phytohemagglutinin (PHA) lectins derived from red kidney beans (Phaseolus vulgaris) in the diet of weanling rats will cause growth failure, malabsorption of nutrients, and bacterial overgrowth in the small intestine. These effects are not caused by feeding a similar quantity of PHA to germfree... |
3860822 | Ancient origin for Hawaiian Drosophilinae inferred from protein comparisons. | Immunological comparisons of a larval hemolymph protein enabled us to build a tree relating major groups of drosophiline flies in Hawaii to one another and to continental flies. The tree agrees in topology with that based on internal anatomy. Relative rate tests suggest that evolution of hemolymph proteins has been abo... |
3860817 | Synchrotron radiation x-ray scattering in the early stages of in vitro collagen fibril formation. | The time course of in vitro collagen fibril formation was monitored by synchrotron radiation x-ray scattering. Collagen polymerization was induced by a temperature jump from 4 degrees C to 32 degrees C and the solution scattering pattern was recorded continuously with a time resolution of a few seconds. The scattered i... |
4040630 | Adenovirus DNA replication in vitro: site-directed mutagenesis of the nuclear factor I binding site of the Ad2 origin. | The template requirements for efficient adenovirus DNA replication were studied in vitro in a reconstituted system with cloned DNA fragments, containing the Ad2 origin region, as templates. Replication is enhanced by nuclear factor I, a cellular protein that binds specifically to the Ad2 origin. This stimulation is sho... |
2410856 | Molecular recognition of B-DNA by Hoechst 33258. | The binding sites of Hoechst 33258, netropsin and distamycin on three DNA restriction fragments from plasmid pBR322 were compared by footprinting with methidiumpropyl-EDTA X Fe(II) [MPE X Fe(II)]. Hoechst, netropsin and distamycin share common binding sites that are five +/- one bp in size and rich in A X T DNA base pa... |
3894933 | Molecular cloning and in vitro expression of a cDNA clone for human cellular tumor antigen p53. | Three clones for the human tumor antigen p53 were isolated from a cDNA library prepared from A431 cells. One of these clones, pR4-2, contains the entire coding region for human p53. This clone directs the synthesis of a polypeptide with the correct molecular weight and immunological epitopes of an authentic p53 molecul... |
4014440 | Extracellular matrix proteins (fibronectin, laminin, and type IV collagen) bind and aggregate bacteria. | The normal microbial colonization of sites in the body's tissues by certain bacteria requires that the bacteria first bind to extracellular secreted constituents, cell-surface membranes, or cell matrixes. This study examines two interactions of a variety of bacteria with the cell matrix noncollagenous proteins fibronec... |
2989817 | Structural analysis of the umu operon required for inducible mutagenesis in Escherichia coli. | The nucleotide sequence of a 2.8-kilobase fragment of the Escherichia coli chromosome containing the umuDC genes has been determined. The DNA sequence specifies two open reading frames of 417 and 1266 nucleotides encoding proteins with calculated molecular weights of 15,063 and 47,677, respectively. From these and the ... |
2989559 | DNA-binding proteins present in varicella-zoster virus-infected cells. | DNA-binding proteins present in varicella-zoster virus-infected cells were identified by DNA-cellulose chromatography of radioactively labeled cell extracts. Seven virus-specific proteins, ranging in molecular weight from approximately 175,000 to 21,000, showed affinity for single- or double-stranded DNA or both. These... |
2989554 | Nucleotide sequence of a transduced myc gene from a defective feline leukemia provirus. | The nucleotide sequence of a feline v-myc gene and feline leukemia virus (FeLV) flanking regions was determined. Both the nucleotide and predicted amino acid sequences are very similar to the murine and human c-myc genes (ca. 90% identity). The entire c-myc coding sequence is represented in feline v-myc and replaces po... |
2989301 | Partial disassembly of peroxisomes. | Rat liver peroxisomes were subjected to a variety of procedures intended to partially disassemble or damage them; the effects were analyzed by recentrifugation into sucrose gradients, enzyme analyses, electron microscopy, and SDS PAGE. Freezing and thawing or mild sonication released some matrix proteins and produced a... |
3924898 | Analysis of Neisseria gonorrhoeae peptidoglycan by reverse-phase, high-pressure liquid chromatography. | The muramidase digest of peptidoglycan from Neisseria gonorrhoeae was isolated and analyzed by the use of a reverse-phase, high-pressure liquid chromatography system. As was found previously in the case of Escherichia coli, gonococci peptidoglycan is also composed of a greater number of muropeptides than can be resolve... |
3891738 | Nucleotide sequence binding specificity of the LexA repressor of Escherichia coli K-12. | The specificity of LexA protein binding was investigated by quantifying the repressibility of several mutant recA and lexA operator-promoter regions fused to the Escherichia coli galactokinase (galK) gene. The results of this analysis indicate that two sets of four nucleotides, one set at each end of the operator (term... |
3924890 | Two homologous genes coding for spore-specific proteins are expressed at different times during development of Myxococcus xanthus. | The ops and tps genes of Myxococcus xanthus have ca. 90% DNA and amino acid sequence homology and are in the same orientation separated by a spacer region of only 1.4 kilobases. The products of the two genes were found to cross-react immunologically, and both were capable of Ca2+-dependent self-assembly on the surface ... |
3937125 | [Structure-activity relationship of semi-synthetic derivatives of the PIA component of pristinamycin]. | Pristinamycin is a naturally occurring streptogramin made up of 2 groups of synergistic components (PI and PII). Because these components are not water soluble, use of pristinamycin has up till now been confined to the oral route. Water soluble semisynthetic derivatives of the PIA component, appropriate for parenteral ... |
3899327 | The filamins: properties and functions. | The filamins are a group of homologous proteins defined by their high native molecular weight (500,000), their amino acid compositions, their cross-reactivity to antibodies to heterologous filamins, their localization to actin networks and bundles in situ, and their ability to cross-link actin filaments in vitro into t... |
3929797 | [Effect of the structure of the prosthetic group on the catalytic properties of prostaglandin H synthetase]. | The effect of vinyl groups of protohemin IX on its cofactor properties with respect to prostaglandin H synthetase has been studied. It was shown that substitution of ethyl groups or a hydrogen for vinyl groups affects neither binding of the prosthetic group to the apoenzyme nor catalytic properties of holo-prostaglandi... |
4034649 | Suppositories containing cyclodextrin complexes. Part 2: Dissolution and absorption studies. | The dissolution and absorption of poorly water-soluble drugs from rectal suppositories can be enhanced by complexing these substances (e.g., essential oils, indomethacin) with beta-cyclodextrin. Preliminary in vivo studies showed, that the application of cyclodextrin complexes to suppositories, the same as to oral appl... |
4033649 | Specific regions of beta-globin RNA are resistant to nuclease digestion in RNA-protein complexes in chicken reticulocyte nuclei. | The interaction between beta-globin RNA and proteins in chicken reticulocyte nuclei was studied by determining the sequence of nuclease-resistant beta-globin RNA. Two types of nuclease-resistant RNAs were isolated for this study: endogenous nuclease-resistant RNA from 50S heterogeneous nuclear RNA-protein complexes and... |
3928670 | Studies of fish zona pellucida by high-performance ion-exchange chromatography on agarose columns and free zone electrophoresis. | By either free zone electrophoresis or high-performance ion-exchange chromatography on DEAE agarose, zona pellucida from Baltic small herring (Clupea harengus L.) was separated into several fractions. These fractions had very similar protein compositions, since on polyacrylamide gel electrophoresis in sodium dodecyl su... |
4027241 | Sedimentation equilibrium measurements of the intermediate-size tobacco mosaic virus protein polymers. | Short-column sedimentation equilibrium methods have been applied for the first time to tobacco mosaic virus (TMV) protein (0.1 M ionic strength orthophosphate) at pH 6.5 and at pH 7.0 to estimate molecular weights. Previous sedimentation velocity experiments at pH 6.5, 20 degrees C have led to the conclusion that the m... |
3160393 | The active cross-bridge motions of isolated thick filaments from myosin-regulated muscles detected by quasi-elastic light scattering. | Intensity fluctuation spectroscopy has been used successfully as a probe that can detect an increase in high-frequency internal motions of isolated thick filaments of Limulus muscle upon the addition of calcium ions. We have attributed such motions to cross-bridge motion instead of to an increase in the flexibility of ... |
4015652 | Synthesis and evaluation of a miniature organic model of chymotrypsin. | An artificial chymotrypsin, with all the features of the real chymotrypsin, namely a binding site (from cyclodextrin) attached to a catalytic site containing an imidazolyl group, a carboxylate group and a hydroxyl group, has been synthesized. This artificial chymotrypsin has a molecular weight of only 1,365 while the r... |
3159884 | Potent enhancement of [3H]nitrendipine binding in rat cerebral cortical and cardiac homogenates: a putative mechanism for the action of MDL 12,330A. | [3H]Nitrendipine [( 3H]NTD), a specific high-affinity calcium channel antagonist, was used to label dihydropyridine binding sites associated with calcium channels in rat cerebral cortical and cardiac homogenates. A novel lactamimide compound, MDL 12,330A, has been shown previously to have negative inotropic and chronot... |
3924955 | Release of arachidonate from membrane phospholipids in cultured neonatal rat myocardial cells during adenosine triphosphate depletion. Correlation with the progression of cell injury. | The present study utilized a cultured myocardial cell model to evaluate the relationship between the release of arachidonate from membrane phospholipids, and the progression of cell injury during ATP depletion. High-energy phosphate depletion was induced by incubating cultured neonatal rat myocardial cells with various... |
3891387 | Cell interaction with the extracellular matrices produced by endothelial cells and fibroblasts. | The extracellular matrices (ECM) produced by cultured bovine corneal endothelial cells and chick embryo fibroblasts were compared for their induction of cell attachment, proliferation and differentiation. The corneal endothelial ECM (cECM) induced a comparable and rapid attachment and flattening of both human Ewing's s... |
3891126 | Cytoskeletal features of rat aortic cells during development. An electron microscopic, immunohistochemical, and biochemical study. | Actin, vimentin, desmin, and tropomyosin distribution in rat aortic endothelial and smooth muscle cells has been studied during development using fetal (18 to 20 days of gestation), and 5- and 14-day-, and 5-, and 12-week-old rats. Endothelial cells of newborn animals actively replicate and contain many actin stress fi... |
3858872 | Caenorhabditis elegans DNA that directs segregation in yeast cells. | We have isolated seven DNA fragments from Caenorhabditis elegans that enhance the mitotic segregation of autonomously replicating plasmids in the yeast Saccharomyces cerevisiae. These segregators, designated SEG1-SEG7, behave like isolated yeast chromosomes: they increase the stability and simultaneously lower the copy... |
3858843 | Supramolecular assemblies of mRNA direct the coordinated synthesis of type I procollagen chains. | Registration of the three procollagen alpha chains and assembly of the triple-helical procollagen molecules takes place in the rough endoplasmic reticulum, but the exact location and timing of assembly is not known. As part of a study of the mechanism of molecular assembly, intact collagen-producing polyribosomes from ... |
3889017 | In cow anterior pituitary, growth hormone and prolactin can be packed in separate granules of the same cell. | The ultrastructural localization of growth hormone and prolactin in cow anterior pituitary was studied by double immunocytochemical labeling using specific antibodies and protein A-gold particles of different sizes. The two hormones were found in specific somatotrophs and mammotrophs as well as in somatomammotropic cel... |
3158664 | The binding of vimentin to human erythrocyte membranes: a model system for the study of intermediate filament-membrane interactions. | We have characterized the association of the intermediate filament protein, vimentin, with the plasma membrane, using radioiodinated lens vimentin and various preparations of human erythrocyte membrane vesicles. Inside-out membrane vesicles (IOVs), depleted of spectrin and actin, bind I125-vimentin in a saturable manne... |
3997891 | Laminin polymerization in vitro. Evidence for a two-step assembly with domain specificity. | Laminin, a major structural glycoprotein of basement membranes, has been found to self-associate in vitro into large polymers. The formation of these complexes can be followed by the development of turbidity upon incubation in neutral phosphate buffer at 21-35 degrees C and is seen to be time-, concentration-, and temp... |
3997776 | Formation of a hexagonal lattice structure by an R-form lipopolysaccharide of Klebsiella sp. | We extracted an R-form lipopolysaccharide (LPS) by the phenol-water method from Klebsiella sp. strain LEN-111 (O3-:KI-) and followed the changes in ultrastructure of the LPS during the extraction procedure. When the LPS was obtained from the water phase of an extract by addition of 2 volumes of 10 mM MgCI2-ethanol, it ... |
2860067 | Protection against Escherichia coli-induced urinary tract infections with hybridoma antibodies directed against type 1 fimbriae or complementary D-mannose receptors. | Hybridoma antibodies directed against quaternary structural epitopes of the type 1 fimbrial adhesin of Escherichia coli or against D-mannose, the sugar determinant in the complementary host cell receptor, prevented the attachment of mannose-sensitive E. coli to various eucaryotic cells. Passive intraperitoneal administ... |
24249608 | Extraction by lithium chloride of hydroxyproline-rich glycoproteins from intact cells of Chlamydomonas reinhardii. | A procedure has been developed to isolate and analyse the cell-wall glycoproteins of Chlamydomonas reinhardii. Under appropriate conditions, cell-wall glycoproteins can be quantitatively extracted from intact cells by aqueous LiCl. Although proteins and glycoproteins, which are presumably not related to the cell wall, ... |
16346823 | Modified medium for the oxidation-fermentation test in the identification of marine bacteria. | Using the medium of ZoBell as a basal formulation, we developed a medium to determine the oxidative-fermentative metabolism in marine bacteria. Different oxidative and fermentative collection strains, as well as a group of unidentified marine bacteria, were tested on modified ZoBell medium and other conventional media.... |
2992927 | PCBs: structure-function relationships and mechanism of action. | Numerous reports have illustrated the versatility of polychlorinated biphenyls (PCBs) and related halogenated aromatics as inducers of drug-metabolizing enzymes and the activity of individual compounds are remarkably dependent on structure. The most active PCB congeners, 3,4,4',5-tetra-, 3,3',4,4'-tetra-, 3,3',4,4',5-p... |
2411299 | [Anti-arrhythmia activity of crown-lactone I and its effect on aconitine-modified sodium channels]. | Antiarrhythmic activity of macrocyclic crown-lactone I as well as its effect on biological and model membranes were studied. Crown-lactone displaces the potential dependence of stationary inactivation of TTX-sensible sodium neurons currents towards more negative potentials reducing the modification of those characteris... |
3875297 | All-reagent test tablets and method for rapid and selective alpha-amylase iodometric determination. | The new type of test tablets (Iodocrom) for alpha-amylase assay contain crosslinked (CL)-amylose or CL-starch (specific substrates for alpha-amylase only) and the reagent (KIO3/KI) generating iodine (in acidic medium, when the reaction is stopped). The method--amyloclastic in nature--is based on selective action of alp... |
4019695 | Microanalyses of beta-cyclodextrin in plasma by high-performance liquid chromatography. | Procedures for the micro-determination of beta-cyclodextrin (beta-CyD) in plasma were investigated by four methods using high-performance liquid chromatography (HPLC). In methods A and B, underivatized beta-CyD was detected with a refractive index detector and determined by the absolute calibration graph method. An NH2... |
4017132 | Mixing of single-chain amphiphiles in two-chain lipid bilayers. 2. Characteristics of chlorophyll a and alpha-tocopherol incorporation in unilamellar phosphatidylcholine vesicles. | As a step toward the elucidation of the biological significance of the isoprenic chains found ubiquitously in single-chain lipids involved in electron and energy transfer of chloroplasts and mitochondria, we undertook a comparative study of the incorporation of chlorophyll a (Chl a) and alpha-tocopherol (alpha T) in un... |
2409732 | Effects of adjuvants to local anaesthetics on their duration. II. Studies of some substituted dextrans and other macromolecules in rat infraorbital nerve block. | The effects of adding various macromolecular substances to 2% prilocaine on duration of rat infraorbital nerve block were investigated. The tested substances consisted of dextrans with lipophilic or charged substituents as well as other neutral or highly charged macromolecules. Most of the adjuvants caused significant ... |
2409473 | Computer simulation of action potentials and afterpotentials in mammalian myelinated axons: the case for a lower resistance myelin sheath. | Depolarizing afterpotentials, recorded in peripheral nerves [Barrett and Barrett (1982) J. Physiol., Lond. 323, 117-144] and spinal axons [Blight and Someya (1985) Neuroscience 15, 1-12], have been interpreted as representing passive discharge of axolemmal capacitance. This interpretation requires a lower resistance pa... |
4004800 | Effect of antituberculous calixarenes on phospholipase A2 susceptibility and on fusion of phospholipid bilayers. | Some homologous calixarenes or polyoxyethylene ethers that are known to suppress or enhance experimental tuberculous infection (depending on their polyoxyethylene chain lengths) were examined for their effects on phospholipid bilayers. The effect of these solutes is seen at 0.5-50p.p.m., and their effect depends upon t... |
2987916 | Molecular cloning and nucleotide sequence of the alpha and beta subunits of allophycocyanin from the cyanelle genome of Cyanophora paradoxa. | The genes for the alpha- and beta-subunit apoproteins of allophycocyanin (AP) were isolated from the cyanelle genome of Cyanophora paradoxa and subjected to nucleotide sequence analysis. The AP beta-subunit apoprotein gene was localized to a 7.8-kilobase-pair Pst I restriction fragment from cyanelle DNA by hybridizatio... |
2987878 | The divergent region of the Leishmania tarentolae kinetoplast maxicircle DNA contains a diverse set of repetitive sequences. | A 2.76 kb segment of the 12 kb divergent region of the Leishmania tarentolae kinetoplast maxicircle DNA consists almost entirely of repeated sequences. The repeats can be grouped into six families, some of which are present throughout the remainder of the divergent region. The repeats are oriented in a head-to-tail fas... |
4000118 | Processing of the precursor to a chloroplast ribosomal protein made in the cytosol occurs in two steps, one of which depends on a protein made in the chloroplast. | In pulse-chase experiments in which log-phase cells of Chlamydomonas reinhardtii were labeled in vivo for 5 min with H2(35)SO4, fluorographs of immunoprecipitates from whole cell extracts revealed that chloroplast ribosomal proteins L-2, L-6, L-21, and L-29, which are made in the cytosol and imported, appeared in their... |
3995027 | Geometric and thermodynamic restrictions for the self-assembly of glycosphingolipid-phospholipid systems. | The thermodynamic and geometrical features of possible self-assembled structures of a series of chemically related glycosphingolipids differing in the complexity of their polar headgroup, and of their mixture with phospholipids, have been predicted according to the theory of self-assembly of hydrocarbon amphiphiles of ... |
3857616 | Morphogenetic rearrangement of injected collagen in developing chicken limb buds. | A fundamental question concerning the development of the extracellular matrix is what factors control the arrangement of collagen fibrils within a tissue and at the same time allow for the great diversity of geometric forms exhibited by collagen. In this report, we test the possibility that physical forces within the e... |
3857600 | Replication initiator protein of plasmid R6K autoregulates its own synthesis at the transcriptional step. | The replication initiator protein of plasmid R6K preferentially repressed transcription initiated in vitro from the promoter of the initiator protein cistron. DNase I protection experiments revealed that the sequences in the region of the promoter recognized by the initiator protein partially overlapped the sequences o... |
2985807 | Deletion in the 3' pol sequence correlates with aberration of RNA expression in certain replication-defective avian sarcoma viruses. | The RNA expression of a series of replication-defective recovered avian sarcoma viruses (rASVs) were studied. Abnormal-sized viral RNAs, both larger and smaller than the genome, were observed in the nonproducer cells infected with rASVs containing env and pol deletions. Each nonproducer clone contained a single proviru... |
3886672 | Polymerization of tubulin in vivo: direct evidence for assembly onto microtubule ends and from centrosomes. | Microtubule assembly in vivo was studied by hapten-mediated immunocytochemistry. Tubulin was derivatized with dichlorotriazinylaminofluorescein (DTAF) and microinjected into living, interphase mammalian cells. Sites of incorporation were determined at the level of individual microtubules by double-label immunofluoresce... |
3988711 | Unusual stability of the Methanospirillum hungatei sheath. | The proteinaceous sheath of Methanospirillum hungatei was isolated by lysing cells in 50 mM dithiothreitol, separating the sheath from other cellular material by discontinuous sucrose density centrifugation, and removing the "cell spacers" with dilute NaOH. The isolated sheath material consisted of hollow tubes which h... |
2580794 | Effect of proteolytic cleavage of surface-exposed proteins on infectivity of Chlamydia trachomatis. | The proteolytic cleavage of Chlamydia trachomatis LGV-434 surface proteins and resultant effects on infectivity and association with cultured human epithelial (HeLa) cells have been examined. Of several proteases examined, trypsin, chymotrypsin, and thermolysin extensively cleaved the chlamydial major outer membrane pr... |
30011974 | The ultrastructure of the cardiac ganglion of the desert scorpion, Paruroctonus mesaensis (Scorpionida: Vaejovidae). | Light and electron microscopy of the pacemaker ganglion of the scorpion heart indicate that it is about 15 mm long and 50 μm in diameter and extends along the dorsal midline of the heart. The largest cell bodies (30-45 μm in diameter) occur in clusters along the length of the ganglion. The ganglion appears to be innerv... |
18553715 | Use of cell affinity chromatography for separation of lymphocyte subpopulations. | We describe the use of affinity chromatography for separation of cell populations that do not differ significantly with respect to gross physical properties such as size, density, or charge. Cell affinity chromatography exploits differences in cell surface macromolecules by passage of mixtures of cell populations throu... |
16346789 | General Biochemical Characterization of Thermostable Extracellular beta-Amylase from Clostridium thermosulfurogenes. | Clostridium thermosulfurogenes, an anaerobic bacterium which ferments starch into ethanol at 62 degrees C, produced an active extracellular amylase and contained intracellular glucoamylase but not pullulanase activity. The extracellular amylase was purified 2.4-fold, and its general physicochemical and catalytic proper... |
4032075 | Nutritional significance of cyclodextrins: indigestibility and hypolipemic effect of alpha-cyclodextrin. | Digestibility of alpha- and beta-cyclodextrin (CD) and nutritional consequences of alpha-CD and a CD mixture (n-dextrin, alpha-, beta-and gamma-CDs = 50, 30, 15 and 5% by weight) were investigated in rats. In contrast with beta-CD, alpha-CD was revealed to be indigestible. Growing rats were fed on diets supplemented wi... |
3161874 | Preparation of non-reducing-end substituted p-nitrophenyl alpha-maltopentaoside (FG5P) as a substrate for a coupled enzymatic assay for alpha-amylases. | p-Nitrophenyl O-6-deoxy-6-[(2-pyridyl)amino]-alpha-D-glucopyranosyl-(1----4)-O-alpha-D - glucopyranosyl-(1----4)-O-alpha-D-glucopyranosyl-(1----4)-O-alpha-D- glucopyranosyl-(1----4)-alpha-D-glucopyranoside, FG5P, was prepared, taking advantage of the action of Bacillus macerans cyclodextrin glucanotransferase on a mixt... |
2990903 | Does unpaired adenosine-66 from helix II of Escherichia coli 5S RNA bind to protein L18? | Adenosine-66 is unpaired within helix II of Escherichia coli 5S RNA and lies in the binding site of ribosomal protein L18. It has been proposed as a recognition site for protein L18. We have investigated further the structural importance of this nucleotide by deleting it. The 5S RNA gene of the rrnB operon of E. coli w... |
4004773 | The assembly of microtubule protein in vitro. The kinetic role in microtubule elongation of oligomeric fragments containing microtubule-associated proteins. | The kinetics of assembly were studied for bovine and pig microtubule protein in vitro over a range of conditions of pH, temperature, nucleotide and protein concentration. The kinetics are in general biphasic with two major processes of similar amplitude but separated in rate by one order of magnitude. Rates and amplitu... |
4000959 | The synthesis of oligonucleotides containing an aliphatic amino group at the 5' terminus: synthesis of fluorescent DNA primers for use in DNA sequence analysis. | A rapid and versatile method has been developed for the synthesis of oligonucleotides which contain an aliphatic amino group at their 5' terminus. This amino group reacts specifically with a variety of electrophiles, thereby allowing other chemical species to be attached to the oligonucleotide. This chemistry has been ... |
3158882 | Macromolecular crowding accelerates the cohesion of DNA fragments with complementary termini. | Macromolecular crowding increases the rate of nonenzymatic cohesion of the complementary ends of lambda DNA. Both lambda DNA and DNA fragments bearing the cohesive ends of lambda DNA are similarly affected. High concentrations of plasma albumin or Ficoll 70 increase the rate of cohesion by ca. 100-fold whereas high con... |
3994692 | Complexing of heparin with phosphatidylcholine. A possible supramolecular assembly of plasma heparin. | In a series of attempts to reveal plasma heparin, we found that high ionic strength and modification of protein amino groups were not effective in extracting endogenous heparin (or, indeed, a large percentage of exogenous labelled heparin), whereas delipidation in the presence of 4M-guanidinium chloride gave high yield... |
3994688 | H.p.l.c. analysis of di- and tri-carboxylic porphyrins in porphyric patients. | New h.p.l.c. methods have been developed for the quantitative determination of di- and tri-carboxylic porphyrin methyl esters, and applied to the analysis of faecal extracts from patients with four different types of porphyria. |
3857585 | Nature of the charged-group effect on the stability of the C-peptide helix. | The residues responsible for the pH-dependent stability of the helix formed by the isolated C-peptide (residues 1-13 of ribonuclease A) have been identified by chemical synthesis of analogues and measurement of their helix-forming properties. Each of the residues ionizing between pH 2 and pH 8 has been replaced separat... |
3157988 | NH2-terminal arm of phage lambda repressor contributes energy and specificity to repressor binding and determines the effects of operator mutations. | Several lines of evidence indicate that the phage lambda repressor recognizes its operator by using, in part, an alpha helix (the "recognition helix"), which it inserts into the major groove of DNA. In addition to its recognition helix, lambda repressor has an "arm," consisting of the first six amino acids, that wraps ... |
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