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7036410 | Bioorganic modelling stereoselective reactions with chiral neutral ligand complexes as model systems for enzyme catalysis. | In terms of the reporting of accomplished chemistry this review can do no more than give an indication of the rapid progress in the branch of bioorganic modelling based on the use of macrocyclic compounds that (usually) act as complexing agents. What remains to be done, however, is to point out problems that have not b... |
37281605 | Transferrin Receptor on Chick Fibroblast Cell Surface and the Binding Affinity in Relevance to the Growth Promoting Activity of Transferrin: (transferrin/receptor/cultured fibroblast/molecular recognition/class dependent specificity). | We examined the transferrin (Tf) receptor of chick skin fibroblasts using chick <sup>125</sup> I-Tf. When the cells were incubated with <sup>125</sup> I-Tf on ice, most of the cell-associated <sup>125</sup> I-Tf was found on the cell surface; on the other hand, a large part of it was located inside the cells when incub... |
7199054 | Correlation between effects of 24 different cytochalasins on cellular structures and cellular events and those on actin in vitro. | To compare the effects of cytochalasins on the cellular level with those on the molecular level, 24 cytochalasins, 20 natural compounds and 4 derivatives, were used. The following effects were tested for each of 24 cytochalasins; (a) four high dose (2-20 muM) effects on the cellular level: rounding up of fibroblastic c... |
7055628 | Structure and function of an acetylcholine receptor. | Structural analysis of an acetylcholine receptor from Torpedo californica leads to a three-dimensional model in which a "monomeric" receptor is shown to contain subunits arranged around a central ionophoretic channel, which in turn traverses the entire 110 A length of the molecule. The receptor extends approximately 15... |
7034799 | Formation of crystalline arrays of chlorophyll a/b - light-harvesting protein by membrane reconstitution. | The structure of the major protein constituent of photosynthetic membranes in higher plants, the chlorophyll a/b-light harvesting complex (LHC), was studied by x-ray diffraction and electron microscopy. The LHC was purified from Triton X-100 solubilized thylakoid membranes of the pea, and contained 6 mol of chlorophyll... |
7055624 | Conformations of model peptides in membrane-mimetic environments. | The influence of a membrane environment on the conformational energetics of a polypeptide chain has been investigated through studies of model peptides in a variety of membrane-mimetic media. Nuclear magnetic resonance (NMR) and circular dichroism (CD) data have been obtained for the peptides in bulk hydrophobic solven... |
6948294 | Protein dynamics by solid-state NMR: aromatic rings of the coat protein in fd bacteriophage. | The motions of the aromatic amino acids of the fd bacteriophage coat protein are described by solid-state 2H, 13C, and 15N NMR. Tryptophan-26 is immobile on time scales as slow as 10(3) HZ. The phenylalanine and tyrosine rings undergo 180 degree flips about the C beta--C gamma bond axis more often than 10(6) HZ as well... |
6274849 | Differential effects of antibiotics inhibiting gyrase. | Both oxolinic acid and coumermycin A1, inhibitors of DNA gyrase, block DNA synthesis in Escherichia coli. At low concentrations of oxolinic acid, the rate of bacterial DNA synthesis first declines rapidly but then gradually increases. This gradual increase in synthesis rate depended on the presence of wild-type recA an... |
6798022 | Synthesis of several membrane proteins during developmental aggregation in Myxococcus xanthus. | We have examined the pattern of synthesis of several membrane proteins during the aggregation phase of development in Myxococcus xanthus. Development was initiated by plating vegetative cells on polycarbonate filters placed on top of an agar medium that supported fruiting body formation. At various times during aggrega... |
6322041 | GABAergic synapses. Supramolecular organization and biochemical regulation. | Extraneurally released gamma-aminobutyric acid (GABA) interacts with specific recognition sites associated with proteins located in postsynaptic neuronal membranes that function as chloride (Cl-)ionophores. As a result of the interaction between GABA and the recognition sites, Cl- ionophores are opened causing an influ... |
6667028 | Supramolecular structure of chlorophyll-protein complexes in relation to the chlorophyll a fluorescence of chloroplasts at room or liquid nitrogen temperature. | To investigate further the possibility that changes in the organization of the thylakoid pigment-protein complexes are monitored by the chlorophyll a fluorescence yield changes, or by changes in the F685/F730 ratio in the 77 degrees K fluorescence, as earlier proposed (A. Castorinis, G. Akoyunoglou, and J.H. Argyroudi-... |
6363968 | Survival and growth of neurons with enkephalin-like immunoreactivity in fetal brain areas grafted to the anterior chamber of the eye. | Areas of fetal rat brain and spinal cord known to contain enkephalin-like immunoreactive cell bodies and/or terminal fields were transplanted to the anterior chamber of the eye of adult rats. Enkephalin-like immunoreactive neurons survive and produce an enkephalin-like immunoreactive fiber network within grafts of spin... |
6196785 | Cell cycle-dependent intervention by benzamide of carcinogen-induced neoplastic transformation and in vitro poly(ADP-ribosyl)ation of nuclear proteins in human fibroblasts. | Human fibroblasts were subjected to nutritionally induced G1 block, followed by release and subsequent entry into S phase, and exposed to nontoxic concentrations of carcinogens in early S phase. Cell transformation occurred as determined by early morphologic cell alterations, anchorage-independent colony formation, cel... |
6580373 | Identification of a new component in the murine Ia molecular complex. | In this report, we describe a previously unidentified component in the murine Ia antigen complex. SDS-PAGE analysis of anti-Ia immunoprecipitates prepared from spleen cells biosynthetically labeled with 35S-sulfate showed no detectable incorporation of 35SO4 into alpha, beta, or Ii chains but did not reveal the presenc... |
6643578 | The changes in structural organization of actin in the sea urchin egg cortex in response to hydrostatic pressure. | We have used hydrostatic pressure to study the structural organization of actin in the sea urchin egg cortex and the role of cortical actin in early development. Pressurization of Arbacia punctulata eggs to 6,000 psi at the first cleavage division caused the regression of the cleavage furrow and the disappearance of ac... |
6605932 | Monocyte-derived soluble suppressor factor(s) in patients with lepromatous leprosy. | Peripheral blood monocytes from polar lepromatous leprosy (LL) patients were unable to support Mycobacterium leprae-induced in vitro lymphoproliferation of HLA-D-matched T cells from tuberculoid leprosy subjects, whereas those from responder individuals were able to do so. Monocyte-rich adherent cells from untreated LL... |
16593399 | Systematic variation of metal-metal bond order in metalloporphyrin dimers. | A general method for synthesizing a novel class of metalloporphyrin dimers containing unbridged metal-metal bonds is presented. By choosing the appropriate metal, the bond order in these dimers can be varied systematically. The synthesis and characterization of osmium(II) and molybdenum(II) porphyrin dimers containing ... |
6229251 | A synthetic crown ether carboxylic acid ionophore displays synergistic transport of Pr3+ in conjunction with lasalocid. | Transport of Pr3+ across phosphatidyl choline vesicles, as monitored by 31P nmr, is second-order in the crown ether carboxylic acid 2, as it is with respect to lasalocid (X-537 A). When the synthetic (2) and the natural (lasalocid) ionophores are incorporated together in approximately 3:1 ratio into the lipidic phase, ... |
6652131 | [Thermography of catalase crystals: the role of crystallographic modification]. | Study of the heat destruction process of catalase crystals by the method of scanning microcalorimetry has revealed the influence of crystallographic modification on protein macromolecules denaturation at relatively low heating rates. |
6359948 | Anaesthesia and the kidney. | Applied anatomy and physiology of the kidney are briefly reviewed. This includes an account of renal blood flow, glomerular filtration rate, juxtaglomerular apparatus, renal autoregulation and intra-renal blood flow distribution, tubular transport mechanisms, solute handling in proximal tubule, function of loop of Henl... |
6580627 | Resonance Raman studies of nitric oxide binding to ferric and ferrous hemoproteins: detection of Fe(III)--NO stretching, Fe(III)--N--O bending, and Fe(II)--N--O bending vibrations. | The nature of bonding interactions between Fe(III) and NO in the ferric nitrosyl complexes of myoglobin (Mb), hemoglobin A (HbA), and horseradish peroxidase (HRP) is investigated by Soret-excited resonance Raman spectroscopy. On the basis of 15NO and N18O isotope shifts, we clearly identified the Fe(III)--NO bond stret... |
6196776 | Engineering of site-directed antisera against vertebrate calmodulin by using synthetic peptide immunogens containing an immunoreactive site. | Site-directed antisera against vertebrate calmodulin were elicited in rabbits by injection of a synthetic immunogen containing the pentadecapeptide Gly-Gln-Val-Asn-Tyr-Glu-Glu-Phe-Val-Gln-Met-Met-Thr-Ala-Lys-OH, which corresponds to residues 134-148 of vertebrate calmodulin. A major immunoreactive region (residues 127-... |
6644599 | Improvement of the oral bioavailability of digitalis glycosides by cyclodextrin complexation. | Inclusion complexes of the digitalis glycosides digitoxin, digoxin, and methyl digoxin with three cyclodextrins (alpha-, beta-, gamma-homologues) in water and in the solid state were studied by a solubility method, IR and 1H-NMR spectroscopy, and X-ray diffractometry. Solid complexes (in a molar ratio of 1:4) of the di... |
6644598 | Complex formation between alpha-cyclodextrin and 4-substituted phenols studied by potentiometric and competitive spectrophotometric methods. | Stability constants for complex formation between alpha-cyclodextrin and the conjugate acid and base forms of nine phenols were measured in aqueous solution at 25 degrees. The potentiometric method, in which the apparent acid dissociation constant of the phenol is measured as a function of cyclodextrin concentration, w... |
6356132 | Enzymatic deacylation of the lipid A moiety of Salmonella typhimurium lipopolysaccharides by human neutrophils. | Lipid A, the toxic moiety of Gram-negative bacterial lipopolysaccharides (endotoxins), is a glucosamine disaccharide to which fatty acid and phosphate residues are covalently attached. Recent studies of Salmonella lipid A indicate that 3-hydroxytetradecanoic acid (3-OH-14:0) residues are directly linked to the glucosam... |
6195295 | A tumor-associated antigen specific for human kappa myeloma cells. | A monoclonal antibody (K-1-21) raised against a kappa Bence Jones protein exhibits unique binding properties to malignant plasma cells. K-1-21 is an IgG1 kappa antibody that reacts with human kappa light chains in free form, but shows no reactivity with heavy chain-associated kappa light chains. By immunofluorescence, ... |
6226669 | Aggregates of acetylcholine receptors are associated with plaques of a basal lamina heparan sulfate proteoglycan on the surface of skeletal muscle fibers. | Hybridoma techniques have been used to generate monoclonal antibodies to an antigen concentrated in the basal lamina at the Xenopus laevis neuromuscular junction. The antibodies selectively precipitate a high molecular weight heparan sulfate proteoglycan from conditioned medium of muscle cultures grown in the presence ... |
6355117 | Regulation of chloroplast membrane function: protein phosphorylation changes the spatial organization of membrane components. | A chlorophyll-protein complex of chloroplast membranes, which simultaneously serves as light-harvesting antenna and membrane adhesion factor, undergoes reversible, lateral diffusion between appressed and nonappressed membrane regions under the control of a protein kinase. The phosphorylation-dependent migration process... |
6313621 | Outer membrane protein K of Escherichia coli: purification and pore-forming properties in lipid bilayer membranes. | Protein K, a recently described outer membrane protein correlated with encapsulation in Escherichia coli (Paakkanen et al., J. Bacteriol. 139:835-841, 1979), has been purified to apparent homogeneity. Purification was based upon the noncovalent association of protein K with peptidoglycan, and the purified protein was s... |
6195146 | Characterization of a cellulose-binding, cellulase-containing complex in Clostridium thermocellum. | The isolation and biochemical characterization of the extracellular form of a cellulose-binding factor (CBF) from Clostridium thermocellum is described. The CBF was isolated from the culture supernatant by a two-step procedure which included affinity chromatography on cellulose and gel filtration on Sepharose 4B. The i... |
6194312 | Monoclonal antibodies to newcastle disease virus: delineation of four epitopes on the HN glycoprotein. | Eighteen independent hybridomas producing monoclonal antibodies to Newcastle disease virus have been prepared by fusion of SP2 cells with spleen lymphocytes from a BALB/c mouse immunized with intact UV-inactivated Newcastle disease virus strain Australia-Victoria. They have been divided into three groups on the basis o... |
6312100 | Marker rescue of temperature-sensitive mutations of vaccinia virus WR: correlation of genetic and physical maps. | The physical map locations of 62 temperature-sensitive mutations of vaccinia virus WR have been determined by marker rescue experiments, using cloned HindIII fragments of wild-type DNA. Since vaccinia virus DNA is not infectious, marker rescue was performed by infecting monolayers of cells at the nonpermissive temperat... |
6401119 | RNA-protein interactions in some small plant viruses. | The structure of the three quasi-equivalent protein subunits A, B and C of the spherical, T = 3 southern bean mosaic virus (SBMV) have been carefully built in accordance with a refined electron density map of the complete virus. The lower electron density in the RNA portion of the map could not be explicitly interprete... |
6321748 | In vivo screening of potential antidotes for chronic cadmium intoxication. | Nineteen chelating agents have been screened under identical conditions of metal loading in an attempt to establish their relative ability to mobilize cadmium from the liver and kidney in mice with chronic cadmium intoxication. The compounds investigated were divided into five groups: polyaminocarboxylic acids, monothi... |
6663444 | Reduction in the local tissue toxicity of chlorpromazine by beta-cyclodextrin complexation. | Effect of beta-cyclodextrin (beta-CyD) on the local tissue toxicity of chlorpromazine (CPZ) was investigated following the intramuscular injection to rabbits. From the gross and histological examinations, beta-CyD was found to alleviate the muscular tissue damage produced by CPZ on M. vastus lateralis in rabbits. The p... |
6644576 | Investigation of the beta-cyclodextrin-hydrocortisone inclusion compound. | The formation of an inclusion compound by beta-cyclodextrin with hydrocortisone has been studied by proton magnetic resonance (1H-NMR) and phase solubility analysis. The magnitude of the chemical shifts of the interior and exterior beta-cyclodextrin protons in the presence of hydrocortisone indicated that hydrocortison... |
6227336 | Formation of a supramolecular complex is involved in the reconstitution of basement membrane components. | Basement membrane macromolecules, including type IV collagen, laminin, and heparan sulfate proteoglycan, do not aggregate when incubated alone. Rather, precipitation occurs in the presence of equimolar amounts of laminin and type IV collagen but variable amounts of heparan sulfate proteoglycan. This interaction require... |
6578853 | Electroimmunoassay. A new competitive protein-binding assay using antibody-sensitive electrodes. | A novel technique is reported in which an antibody-sensitive electrode for anti-prostaglandin E2 antisera was used to measure solution-phase PGE2 in nanomolar quantities. The electrode was constructed by incorporating a cation-selective ionophore-hapten (PGE2) conjugate into a polyvinyl chloride membrane. Transmembrane... |
6626170 | Haem disorder in modified myoglobins. Effect of reconstitution procedures. | Apomyoglobin was reconstituted with deuterohaem derivatives under various conditions. The fraction of disordered component, which is characterized by a 180 degree rotation of the haem group, for the various preparations was determined by n.m.r. spectroscopy. By using the procedures described, it was shown that the frac... |
6312458 | pH regulation of divalent/monovalent Ca/K cation transport selectivity by a macrocyclic carrier molecule. | The lipophilic dicarboxylic acid-dicarboxamide macrocycle 1 is an efficient carrier for calcium and potassium transport through a liquid membrane. The process involves competitive Ca2+/K+ symport coupled to proton antiport in a pH gradient. It presents a very pronounced phenomenon of pH regulation of transport selectiv... |
6578515 | Production and characterization of a monoclonal antibody directed against the 43,000-dalton v1 polypeptide from Torpedo marmorata electric organ. | Subsynaptic membrane fragments prepared from Torpedo marmorata electric organ contain, in addition to the acetylcholine receptor polypeptides, a major protein band of apparent molecular mass 43,000 daltons. On two-dimensional gels, this band yields three spots referred to as v1, v2, and v3. Monoclonal antibodies agains... |
6578510 | Chromosomal mapping of the mink cell focus-inducing and xenotropic env gene family in the mouse. | Chromosomal locations of members of the xenotropic-related env gene family in the mouse genome have been determined. Endonuclease restriction site polymorphisms detected by molecular hybridization were used to study the inheritance of mink cell-focus inducing and xenotropic env gene-related sequences in recombinant inb... |
6615193 | Exploratory laparotomy for potential abdominal sepsis in patients with multiple-organ failure. | We studied 29 patients with multiple-organ failure (MOF) who underwent exploratory laparotomy because of suspected intra-abdominal sepsis. The purpose was to identify predictors of continuing abdominal sepsis and to assess outcome of operation in these severely ill patients. The strongest predictor of continuing intra-... |
24221705 | Mass balance of heavy metal uptake by encapsulated cultures ofKlebsiella aerogenes. | Dialysis was employed as a method of speciating heavy metals in cultures of an extracellular polymer forming strain ofKlebsiella aerogenes. A noncapsulated strain of the same bacterium was used as a control, and a mass balance of copper, cadmium, cobalt, nickel, and manganese in batch culture at pH 4.5 and pH 6.8 and i... |
16593377 | Chlamydomonas agglutinin is a hydroxyproline-rich glycoprotein. | The mt(+) sexual agglutinin from Chlamydomonas reinhardi is shown to contain approximately 12% hydroxyproline, and two inhibitors of hydroxyproline formation, alpha,alpha'-dipyridyl and 3,4-dehydroproline, are shown to block the production of agglutinin activity in an in vivo bioassay system. These results indicate tha... |
6433582 | Supramolecular structures in mycoplasmas. | Mycoplasma pneumoniae cells treated with Triton X-100 showed a detergent-resistant cytoskeleton. This cytoskeleton consists of microfilaments which seem related to eukaryotic actin filaments, both morphologically and in some chemical properties, including specific staining by anti-actin antibodies and rhodamine-labeled... |
6676662 | [Reappraisal of clinical pictures of multiple organ failure]. | Disseminated intravascular coagulation syndrome (DIC) and also multiple organ failure (MOF) still remain principal causes of death after major surgery or trauma. The author tried to reappraise the clinical features of MOF, especially with the special reference to DIC. One hundred and thirty three cases with MOF were co... |
6427597 | [Fungal sepsis and DIC in surgical patients]. | Of 53 surgical cases complicated with severe infection who were admitted to The Second Department of Surgery of Osaka University Hospital between 1975 and 1982, 9 cases were suffered from sepsis with positive blood culture for Candida albicans. All cases developed DIC and subsequent multiple organ failures (MOF), which... |
6427596 | [Severe surgical infection and DIC]. | Severe surgical infection is one of the most obvious clinical settings of DIC. Although many initiating triggers have been discussed, the most potent might be a bacterial endotoxin which activates Hageman factor or some components of serum complement. We examined a disorder of blood coagulation system in severe surgica... |
6676659 | [The role of multiple organ failure in DIC]. | The records of 27 cases of disseminated intravascular coagulation with burn, trauma, perforated peritonitis or leakage of gastrointestinal anastomoses at the Second Department of Surgery and Intensive Care Unite, Toho University Hospital from 1977 to 1982 were reviewed. In this series, multiple organ failure (MOF) occu... |
6676657 | [Development of MOF as result of DIC. Clinical and experimental studies]. | Sixty three percent of 60 cases of clinically diagnosed Disseminated Intravascular Coagulation (DIC) developed to Multiple Organ Failure (MOF) and the mortality was high in the group which showed organ failure before the manifestation of DIC. The mortality of MOF cases was 91.6% and the presence of organ failure before... |
6660999 | An experimental study of the influence of sensory nerve fibers on Merkel cell differentiation in the labial mucosa of the rabbits. | The influence of the sensory nerve fibers on the differentiation of the Merkel cell was examined in the denervated labial mucosa of adult rabbits. Part of the lower labial mucosa was excised following mental nerve resection. Twenty-one and 50 days later, the regenerated mucosa was examined by electron microscopy with s... |
6197534 | Supramolecular aggregation and organization in peripheral nerve myelin. | Under certain preparative conditions the lipid bilayers of glutaraldehyde-fixed, PNS myelin demonstrate a marked compartmentalization, which can be augmented by lipid extraction following sectioning. The results are interpreted as indicating a supramolecular domain pattern of arrangement centered upon the transmembrane... |
6417942 | Abstracts of papers presented at the 8th workshop of the Virology Section of the Deutsche Gesellschaft für Hygiene und Mikro-biologie, Würzburg, March 17-19, 1983. | 17 adenovirus strains were found to be antigenically related to prototype Ad 15 by neutralization. No relationship to Ad 15, but to Ad 9 could be detected by hemagglutination-inhibition; we therefore named them Ad 15/H9 intermediate strains. After analysis of the genome by five different restriction enzymes, the fragme... |
6626525 | Assembly and calcium-induced cooperativity of Limulus IV hemocyanin: a model system for analysis of structure-function relationships in the absence of subunit heterogeneity. | Hemocyanins, the high molecular weight copper proteins which serve as oxygen carriers in many arthropods and molluscs, are representative of multisubunit complexes which are capable of reversible dissociation and assembly. Although reversible, in many hemocyanins these processes are not in true thermodynamic equilibria... |
6625610 | The isolation and characterization of specific 3-methylcholanthrene-binding proteins from rat liver cytosol. | The major proteins to which 3-methylcholanthrene specifically binds have been purified over 480-fold with a 45% yield compared to a rat liver 100,000g supernate. The procedure involved a batch ion-exchange technique together with hydrophobic gel filtration and chromatofocusing chromatography. The multiple, specific 3-m... |
6620431 | Multiple organ failure in polytrauma patients. | To determine limitations in survival and problems of single and multiple organ failure (SOF, MOF) following trauma in Bavaria, we reviewed 433 consecutive patients with multiple injuries treated at the Klinikum Grosshadern from 1978 through 1982. Most patients were young and were injured in traffic accidents. The overa... |
6411805 | Cytochemical studies of nuclear basic proteins in control and vitamin B12 starved Euglena. | In avitaminosis B12, Euglena gracilis Z is blocked in the cell cycle in the S/G2 phase. In these blocked cells, transcription and traduction go on and the amount of DNA is less than doubled and remains constant during the blockage. Chromatin clumps observed in situ with classical electron microscopic methods are always... |
6885927 | Developmental acquisition of basement membrane heterogeneity: type IV collagen in the avian lens capsule. | To investigate potential heterogeneity and developmental changes in basement membranes during embryogenesis, we performed immunohistochemical analyses on lens capsules in chicken embryos of different ages using domain-specific monoclonal antibodies against type IV collagen. We found that the capsule of the newly formed... |
6350320 | Scanning electron microscope-analysis of the protrusions (knobs) present on the surface of Plasmodium falciparum-infected erythrocytes. | The nature of the surface deformations of erythrocytes infected with the human malaria parasite Plasmodium falciparum was analyzed using scanning electron microscopy at two stages of the 48-h parasite maturation cycle. Infected cells bearing trophozoite-stage parasites (24-36 h) had small protrusions (knobs), with diam... |
6224790 | Anion effects on in vitro sarcoplasmic reticulum function. Co-transport of anions with calcium. | In isolated sarcoplasmic reticulum vesicles, calcium-chelating but non-calcium-precipitating dicarboxylates, such as maleate and succinate, stimulated ATP-dependent Ca2+ accumulation and its ensuring spontaneous Ca2+ accumulation and its ensuring spontaneous Ca2+ release, and Ca2+-dependent ATPase activity (Chu, A., Ta... |
6350274 | Evidence for diffuse growth of the cylindrical portion of the Escherichia coli murein sacculus. | High-resolution autoradiography of thin sections of Escherichia coli cells whose murein was pulse-labeled with [3H]diaminopimelic acid after a period of diaminopimelic acid deprivation indicated that elongation of the murein sacculus occurs by a multisite (diffuse) process. Upon chasing, radioactivity in polar murein w... |
6411682 | Iodination of Myxococcus xanthus during development. | Intact cells of Myxococcus xanthus were iodinated with [125I]lactoperoxidase to permit examination of the surface components accessible to labeling during cell development. Vegetative cells, starved on a defined solid medium, aggregated, formed fruiting bodies, and produced myxospores. Cells collected at different stag... |
6136463 | Monoclonal antibodies against colonization factor antigen I pili from enterotoxigenic Escherichia coli. | Hybridomas secreting monoclonal antibodies directed against intact colonization factor antigen I pili have been produced by the fusion of spleen cells from immunized BALB/c mice with NS1/SP2 myeloma cells. The four monoclones with the highest antibody titer, as detected by enzyme-linked immunosorbant assay (ELISA), wer... |
6885158 | Comparative hydrophobicities of oral bacteria and their adherence to salivary pellicles. | Oral bacteria were found to differ in their surface hydrophobicities as determined by their ability to adsorb to hexadecane. Strains of Actinomyces viscosus, A. naeslundii, Streptococcus sanguis, S. mitis, and Bacteroides gingivalis proved highly hydrophobic. Strains of B. intermedius, S. salivarius, S. mutans, and B. ... |
6309661 | Effect of heptakis (2,6-O-dimethyl) beta-cyclodextrin on the production of pertussis toxin by Bordetella pertussis. | The effect of heptakis (2,6-O-dimethyl) beta-cyclodextrin (Me beta CD) on the production of pertussis toxin was evaluated. The addition of Me beta CD to the medium stimulated cell growth and pertussis toxin production. Me beta CD enhanced pertussis toxin production 100 times more in synthetic media, such as Stainer-Sch... |
6626599 | [Dynamic organization of the electron transport chain in bacterial membrane by radiation inactivation]. | A complete cross-linking of proteins in isolated Micrococcus lysodeikticus membranes under effect of glutaric aldehyde causes 50% inhibition of the NADH-oxidase activity. Using the irradiation inactivation procedure, it was demonstrated that the size of the irradiation target for NADH-oxidase coincides with that for NA... |
6194817 | Complexation and phase transfer of nucleotides by gramicidin S. | Gramicidin S (GrS), an amphiphilic cyclosymmetric decapeptide produced by Bacillus brevis G-B and Nagano, binds nucleotides in water to yield a complex which partitions into organic solvents. The observed phase-transfer efficiencies at a given pH increase in the order AMP less than ADP less than ATP. The lipophilic com... |
6225991 | Some comments on extraction analysis of cations complexed with a crown ether. | A brief review is given on the use of crown ethers in solubilizing salts of alkali and alkaline earth ions in organic polar or apolar solvents. Use of crown ethers can also be made in testing e.g. lithium salts for potassium by extraction as LKpicrate, L being 18-crown-6. |
6688532 | Proton nuclear magnetic resonance investigation of the mechanism of flavin C-4a adduct formation induced by oxidized nicotinamide adenine dinucleotide binding to monoalkylated pig heart lipoamide dehydrogenase. | The active center thiol of monoalkylated pig heart lipoamide dehydrogenase, EHR, is induced to form an adduct to the enzyme-bound flavin adenine dinucleotide (FAD) at the C-4a position upon binding oxidized nicotinamide adenine dinucleotide (NAD+) [Thorpe, C., & Williams, C. H., Jr. (1976) J. Biol. Chem. 251, 7726-7728... |
6310301 | Minireview. Roles of turnover and repair of macromolecules and supramolecular structural components. | Macromolecules and supramolecular structural components that are incorrectly synthesized or are damaged by radiation or by reactive chemicals are either repaired or selectively degraded and resynthesized. In addition, turnover rates for macromolecules and supramolecular structures can be elevated by alternation of fast... |
6885912 | Binding sites of calmodulin and actin on the brain spectrin, calspectin. | We used rotary-shadowing electron microscopy to map the calmodulin-and actin-binding sites on the brain spectrin, calspectin (or fodrin). Calspectin dimers appeared as rods 110 nm long and joined in a head-to-head manner to form tetramers 220 nm long. We determined calmodulin-binding sites by a ferritin-labeling method... |
6309863 | Binding of fibronectin to alpha-granule-deficient platelets. | Most of the proposed functions for fibronectin involve its interaction with cells, yet the molecular nature of cellular fibronectin binding site(s) has remained obscure. Thrombin induces saturable platelet binding sites for plasma fibronectin and concurrently stimulates surface expression of a number of platelet alpha-... |
6308674 | Modulation of neuronal serotonin uptake by a putative endogenous ligand of imipramine recognition sites. | Imipramine inhibits the serotonin uptake by binding with high affinity to regulatory sites of this uptake located on axons that release serotonin. The number of imipramine recognition sites located on crude synaptic membrane preparations is reduced by two daily injections of imipramine or desmethylimipramine for 3 week... |
6308635 | ts A1S9 locus in mouse L cells may encode a novobiocin binding protein that is required for DNA topoisomerase II activity. | Nuclear novobiocin binding proteins (NBPs) from a set of mouse L cells have been extensively purified by affinity chromatography on novobiocin-Sepharose columns. The NBPs, specifically eluted with 100 micrograms of novobiocin per ml, exhibited equivalent DNA topoisomerase activities (measured as ATP-dependent relaxatio... |
6308470 | Determination of the absolute handedness of knots and catenanes of DNA. | DNA winds about itself in a right-handed or left-handed fashion at several structural levels. The double helix is generally right-handed and is given a (+) sign by convention, whereas supercoiling of the helix axis is always (-) in the cell. The winding in higher -order forms such as knots and catenanes is unknown, and... |
6308058 | Specific plasma membrane receptors for reovirus on rat pituitary cells in culture. | Specific cellular and host tropism is a characteristic property of many viruses mediated by the interaction of viral attachment proteins with components of the plasma membrane of the cell. We have studied the binding of virus to cells quantitatively by using type 3 reovirus labeled with 125I and GH4C1 pituitary cells i... |
6135665 | Monoclonal immunoglobulin M antibody to Japanese encephalitis virus that can react with a nuclear antigen in mammalian cells. | An immunoglobulin M (IgM) class monoclonal antibody raised against Japanese encephalitis virus reacted with an epitope on the nonstructural virus protein P74 (NV4 in the old nomenclature) of several flaviviruses and also with an antigen present in the nuclei of a variety of mammalian cell types. This antigen had a char... |
16593352 | Charged amino acids as spectroscopic determinants for chlorophyll in vivo. | In this paper we propose that the large spectroscopic red shifts observed for chlorophyll (Chl) and bacteriochlorophyll (BChl) in vivo may be due to charged amino acids in the binding site. Molecular orbital calculations of the transition energies of Chl in the field of external charges are carried out. The calculated ... |
16346362 | Quantitative high-pressure liquid chromatography-fluorescence determination of some important lower Fatty acids in lake sediments. | For the quantitative determination of traces of fatty acids in pore water, several gas and liquid chromatographic methods were tested and discussed. Direct determination by gas-liquid chromatography with the use of formic acid-saturated carrier gas was found to be the least laborious method, but it is only recommended ... |
6207845 | [Modification of sulfhydryl groups in ribosomal proteins by a dinitrophenyl hapten]. | A dinitrophenyl hapten capable of protein SH-group modification was synthesized and the specificity of its reaction with SH-groups of the E. coli ribosomal proteins was studied. The possibility of incorporation of the Dnp-modified protein into ribosomal subunits by in vitro reconstitution was demonstrated with the ribo... |
6625552 | Minimal inhibitory concentrations of lucknomycin, a new polyenic derivative, for Candida and Aspergillus spp. | The minimal inhibitory concentrations (MICs) of lucknomycin, a new polyenic derivative, were determined for 101 clinical isolates of Candida, 38 clinical or environmental strains of Aspergillus fumigatus, and 30 isolates of A. niger. The most susceptible species were Candida albicans and Candida tropicalis (mean MIC, 0... |
6624454 | An ultrastructural study on periductal elastosis in human breast tumors. | An ultrastructural study on elastosis of human breast tumors was made with special attention to the periductal elastosis and the cell responsible for elastic fiber formation. The elastosis was found prominently in scirrhous type of duct carcinoma. In the area of mild periductal elastosis, the elastic fibers with many m... |
6194150 | Interaction of native and SH-modified beta-amylase of soybean with cyclohexadextrin and maltose. | Cyclohexadextrin and maltose bound to soybean beta-amylase and affected the environments of tryptophan and tyrosine residues, producing characteristic difference spectra in the ultraviolet region. The difference spectrum produced by cyclohexadextrin, a competitive inhibitor, had peaks at 285, 292, and 299 nm, while tha... |
6684411 | Cytoskeletal disorganization induced by local application of beta, beta'-iminodipropionitrile and 2,5-hexanedione. | Beta, beta'-Iminodipropionitrile and 2,5-hexanedione are neurotoxins that produce neurofilamentous axonal swellings. The swellings produced experimentally with these agents are similar in structure but different in distribution. Neither the relationships between these agents nor the mechanisms of action are known. In t... |
6885992 | Modified oxidation-fermentation medium for detection of acid production from carbohydrates by Neisseria spp. and Branhamella catarrhalis. | A modified oxidation-fermentation medium was developed as a practical medium for highly sensitive and specific detection of acid production from carbohydrates by Neisseria spp. and Branhamella catarrhalis. A total of 756 strains representing 17 Neisseria spp. and Branhamella catarrhalis were tested in this medium, in w... |
6350251 | Holes in the reticular lamina after noise exposure: implication for continuing damage in the organ of Corti. | Three different histological techniques (scanning electron microscopy, phase contrast microscopy and light microscopy) were used to examine the organ of Corti after a damaging noise exposure. In the region of maximal injury, all outer hair cells were missing 1-2 h after the exposure had ended. Degenerated hair cells ar... |
6309262 | Saturation transfer EPR spectroscopy on spin-labeled muscle fibers using a loop-gap resonator. | Previously, saturation transfer (ST-EPR) studies of biomolecular dynamics have involved the use of a resonant cavity and the V'2 display (absorption, second harmonic, out of phase). In the present study, we replaced the resonant cavity with a loop-gap resonator and used the U'1 display (dispersion, first harmonic, out ... |
6874946 | Inhibition of phagocytosis of complement C3- or immunoglobulin G-coated particles and of C3bi binding by monoclonal antibodies to a monocyte-granulocyte membrane glycoprotein (Mol). | Events that lead to phagocytosis of complement (C3)- or IgG-coated particles after their interaction with specific cell surface receptors are poorly understood. Two mouse monoclonal antibodies (an IgM and an IgG2a) to a human granulocyte-monocyte surface membrane differentiation antigen (Mol) inhibited ingestion by gra... |
6191773 | Supramolecular organization of lysophosphatidylcholine-packaged Gramicidin A. | Heat derived gramicidin A'/L-alpha-lysophosphatidylcholine complexes were separated on a sucrose gradient to form two fractions: Fraction A which had an approximately constant Gramicidin A' to phospholipid ratio of 8 to 10 lipid molecules per Gramicidin A' molecule and Fraction B which had a larger but variable ratio. ... |
6865649 | Cycloamylose complexation of adamantane derivatives. | Spectrophotometric and pH potentiometric studies indicate that cyclohexaamylose (alpha-cyclodextrin) and cycloheptaamylose (beta-cyclodextrin) form aqueous complexes with all adamantane derivatives examined to date. Thermodynamic complex formation constants are reported for the substrates 1-adamantaneamine (amantadine)... |
6191040 | Herpes simplex virus type 2 glycoprotein gF and type 1 glycoprotein gC have related antigenic determinants. | The 104-S monoclonal antibody immunoprecipitated from herpes simplex virus type 2 (HSV-2)-infected cell extracts the 75,000-molecular-weight glycoprotein gF and its 65,000-molecular-weight precursor (pgF). The precursor pgF was sensitive to endoglycosidase H digestion, indicating the presence of high mannose-type oligo... |
6306267 | Simian virus 40 tumor antigen: isolation of the origin-specific DNA-binding domain. | To localize the origin-specific DNA-binding domain on the simian virus 40 tumor (T) antigen molecule, we used limited proteolysis with trypsin to generate fractional peptides for analysis. A 17,000-Mr peptide was found to be capable of binding not only to calf thymus DNA, but also specifically to the simian virus 40 or... |
6190977 | T and B cells that recognize the same antigen do not transcribe similar heavy chain variable region gene segments. | We have attempted to determine whether T cells and B cells that have the same antigenic specificity and whose receptors share idiotypic determinants in fact express similar VH gene segments. To do this, we have obtained and characterized a cDNA clone containing the entire coding sequence for the VH gene from a glutamic... |
6190820 | The 50- and 58-kdalton keratin classes as molecular markers for stratified squamous epithelia: cell culture studies. | The keratins are a highly heterogeneous group of proteins that form intermediate filaments in a wide variety of epithelial cells. These proteins can be divided into at least seven major classes according to their molecular weight and their immunological reactivity with monoclonal antibodies. Tissue-distribution studies... |
6305916 | Coliphage P1-mediated transduction of cloned DNA from Escherichia coli to Myxococcus xanthus: use for complementation and recombinational analyses. | We have found that coliphage P1 can be used to transduce cloned DNA from Escherichia coli to Myxococcus xanthus. Transduction occurred at a high efficiency, and no evidence for DNA restriction was observed. The analysis of the transductants showed that they fall into three general categories: (i) haploid cells which co... |
6305906 | Nitrogen fixation and ammonia switch-off in the photosynthetic bacterium Rhodopseudomonas viridis. | Rhodopseudomonas viridis ATCC 19567 grows by means of nitrogen fixation in yeast extract-N2 or nitrogen-free medium when sparged with 5% CO2 and 95% N2 in the light at 30 degrees C. Acetylene reduction assays for nitrogenase activity revealed an initially high level of activity during early-logarithmic growth phase, a ... |
6134679 | Association of fimbriae with the hydrophobicity of Streptococcus sanguis FC-1 and adherence to salivary pellicles. | A nonhydrophobic mutant of Streptococcus sanguis FC-1 was isolated which has a greatly diminished capacity for attaching to experimental salivary pellicles on hydroxyapatite surfaces and for aggregating with salivary components. The mutant appears to be defective in the synthesis of fimbriae, as judged by electron micr... |
6683168 | Comparative receptor study in gamete chemotaxis of the seaweeds Ectocarpus siliculosus and Cutleria multifida. An approach to interspecific communication of algal gametes. | Gamete fusion in phaeophytes is initiated by olefinic hydrocarbons as messenger substances. They are secreted by the female gametes and act on male gametes or gametangia. The sensitivity thresholds of the androgametes of Ectocarpus siliculosus and Cutleria multifida, two brown algae of different evolutionary stages, fo... |
6207844 | [Lipopolysaccharide-protein complexes of the outer membrane of gram-negative bacteria]. | The evidence for occurring lipopolysaccharide-protein complexes in the outer membrane of gram-negative bacteria has been summarized. The composition and supramolecular structure of these complexes as well as their functions in microbial envelope and substantial role in membrane organization have been discussed. The bio... |
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