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3255754 | Dissociation and re-assembly of the endoplasmic reticulum in live cells. | The endoplasmic reticulum (ER) of a typical interphase 3T3 fibroblast consists of a compact perinuclear arrangement of cisternae and lamellae which can be observed by immunofluorescence with anti-endoplasmin. During mitosis the reticulum dissociates into small fragments from which it appears to re-assemble in the daugh... |
3150000 | Relative affinity of 5-methoxypsoralen and 8-methoxypsoralen towards beta-cyclodextrin: a fluorescence, circular dichroism and chromatographic study. | The relative affinity of 5-methoxypsoralen (5-MOP) and 8-methoxypsoralen (8-MOP) towards beta-cyclodextrin, a good model for the study of lipophilic interactions in biological systems and a potential drug carrier, has been investigated using spectroscopic and chromatographic methods. The fluorescence emission of 5-MOP ... |
3246527 | Computer-aided optimisation of drug enantiomer separation in chiral high-performance liquid chromatography. | The advent of several new column materials for the resolution of chiral compounds in high-performance liquid chromatography has opened up new possibilities for the analysis of drug enantiomers both in the dosage form and in bioanalytical studies. The utility of simplex optimisation, modified simplex and response surfac... |
3072473 | The intron-containing gene for yeast profilin (PFY) encodes a vital function. | The gene coding for profilin (PFY), an actin-binding protein, occurs as a single copy in the haploid genome of Saccharomyces cerevisiae and is required for spore germination and cell viability. Displacement of one gene copy in a diploid cell by a nonfunctional allele is recessively lethal: tetrad analysis yields only t... |
3072471 | Dynamic changes in the structure and intracellular locale of the mammalian low-molecular-weight heat shock protein. | Mammalian cells grown at 37 degrees C contain a single low-molecular-weight heat shock (or stress) protein with an apparent mass of 28 kilodaltons (kDa) whose synthesis increases in cells after exposure to elevated temperatures or other forms of physiologic stress. Herein we present data demonstrating that heat shock p... |
3072080 | Malto-oligosaccharide homologues of 3,7-anhydro-2-azi-1,2-dideoxy-D-glycero-D-gulo-octitol+ ++: improved photoaffinity reagents for labelling the malto-oligosaccharide-binding protein of Escherichia coli. | 3,7-Anhydro-2-azi-1,2-dideoxy-D-glycero-D-gulo-octitol (2) was synthesized as a beta-D-glucopyranosyl analogue, which could be converted into a series of malto-oligosaccharide derivatives (3-7) by cyclodextrinase-catalyzed glucosyl transfer from alpha-cyclodextrin (cyclomaltohexaose). The pure analogues 3-7 containing ... |
3242637 | In situ optical spectroscopy of some systems of biological interest. | Monitoring the optical absorption or emission spectrum of a condensed phase sample offers information about the supramolecular assembly, packing effects and other features characteristic of the phase that would be missed when one studies solution-state spectra. We have used the technique of photoacoustic spectroscopy t... |
3241229 | The use of complementary peptides in the purification of an angiotensin II binding protein. | We used the molecular recognition hypothesis, that peptide ligands and their receptor binding sites are encoded by complementary nucleotide sequences, to purify an angiotensin II (Ang II) binding protein. The complementary peptide IIA (Lys-Gly-Val-Asp-Val-Tyr-Ala-Val) specified by the RNA sequence complementary to the ... |
2906641 | Use of supplemented Stainer-Scholte broth for the isolation of Bordetella pertussis from clinical material. | The use of Stainer-Scholte broth supplemented with (2,6-O-dimethyl)beta-cyclodextrin (heptakis) for the isolation of Bordetella pertussis from clinical specimens was evaluated with 3,632 nasal swabs from children and adults with suspected whooping cough or from their family contacts. The liquid enrichment medium was su... |
2465706 | New technique for differential staining of myelinated fibers and nerve cells on paraffin sections. | A simple, rapid method for the differential staining of myelinated nerve fibers and nerve cell bodies, applicable to sections of central nervous system pieces embedded in paraffin, is described. Experimental material fixed by perfusion with mixed aldehydes or necropsy material fixed in formaldehyde can be used. Constan... |
3147335 | Effects of arachidonic acid and the other long-chain fatty acids on the membrane currents in the squid giant axon. | The effects of arachidonic acid and some other long-chain fatty acids on the ionic currents of the voltage-clamped squid giant axon were investigated using intracellular application of the test substances. The effects of these acids, which are usually insoluble in solution, were examined by using alpha-cyclodextrin as ... |
2852132 | Oligosaccharides in molecular recognition. | The development, organization and growth of complex organisms as well as their interactions with the environment involve an intricate array of molecular recognition events. There is an increased awareness of the involvement of oligosaccharides in many of these processes. In this article, studies of oligosaccharide anti... |
3223929 | Supracrystallographic resolution of interactions contributing to enzyme catalysis by use of natural structural variants and reactivity-probe kinetics. | 1. The influence on the reactivities of the catalytic sites of papain (EC 3.4.22.2) and actinidin (3.4.22.14) of providing for interactions involving the S1-S2 intersubsite regions of the enzymes was evaluated by using as a series of thiol-specific two-hydronic-state reactivity probes: n-propyl 2-pyridyl disulphide (I)... |
3223920 | Degradation of basement membranes by human matrix metalloproteinase 3 (stromelysin). | Connective tissue cells synthesize and secrete a group of matrix metalloproteinases (MMPs), all of which are capable of degrading the extracellular-matrix components. One of them, MMP-3 (stromelysin) has been shown to degrade purified basement-membrane components, collagen IV and laminin [Okada, Y., Nagase, H. & Harris... |
3065521 | RecA protein self-assembly. Multiple discrete aggregation states. | Light scattering, sedimentation and electron microscopy have been used to investigate the aggregation states of highly purified RecA protein in solution. We show that RecA protein will self-assemble into a discrete series of quaternary structures depending upon protein concentration, ionic environment, and nucleotide c... |
3217235 | Contraluminal para-aminohippurate (PAH) transport in the proximal tubule of the rat kidney. IV. Specificity: mono- and polysubstituted benzene analogs. | In order to study the specificities of the contraluminal anion transport systems, the inhibitory potency of substituted benzene analogs on influx of [3H]PAH, [14C]succinate, and [35S]sulfate from the interstitium into cortical tubular cells has been determined in situ: (1) Contraluminal [3H]PAH influx is moderately inh... |
2975160 | Lanthanum as a calcium-substituting ion for binding to sarcoplasmic reticulum ATPase. | Ca2+ binding and internalization in sarcoplasmic reticulum ATPase can be investigated by the use of La3+ as a Ca2+ analog. Displacement kinetics of Ca2+ bound by La3+ in native vesicles is a slow biphasic process (k1 = 0.55 s-1 and k2 = 0.05 s-1) that is consistent with the existence of two Ca2+ binding populations whe... |
2850540 | Specific binding of o-phenanthroline at a DNA structural lesion. | DNA intercalators are found to recognize a DNA lesion as a high affinity receptor site. This lesion-specific binding is observed when one strand of a DNA double helix contains an extra, unpaired nucleotide. Our assay for binding controls for the effects of sequence with a series of oligodeoxynucleotide duplexes which a... |
2905265 | Secretion of cyclolysin, the calmodulin-sensitive adenylate cyclase-haemolysin bifunctional protein of Bordetella pertussis. | The calmodulin-sensitive adenylate cyclase of Bordetella pertussis, a 45 kd secreted protein, is synthesized as a 1706 amino acid precursor. We have shown that this precursor is a bifunctional protein, carrying both adenylate cyclase and haemolytic activities. The 1250 carboxy-terminal amino acids of the precursor show... |
3208133 | Immunoelectron microscopic localization of actin in neurites of cultured embryonic chick dorsal root ganglia: actin is a component of granular, microtubule-associated crossbridges. | Axons have been shown to contain substantial quantities of actin distributed along their length. However, the general lack of information on the structure and organizational state of this protein in axons has made it difficult to assign it a functional role. In the present study, we used electron microscopic immunocyto... |
3207882 | [Dynamics of the recovery of the structure and function of the sciatic nerve and skin receptors in reinnervation of the hindlimb of white rats]. | The dynamics of the structural and functional repair of nerve trunks and receptor endings in the rat foot skin was studied on the model of sutureless connection of the damaged nerve by and implanted arterial vessel. Neurohistological and neurophysiological methods were used to show that the anatomical repair of the ner... |
3060469 | Spatial pattern of myosin phosphorylation in contracting smooth muscle cells: evidence for contractile zones. | We have purified a polyclonal antibody by affinity chromatography which binds specifically to the phosphorylated form of the regulatory light chain (Mr = 20,000) of smooth muscle myosin. This antibody does not stain relaxed, permeabilized smooth muscle cells isolated from guinea pig taenia coli. However, when these cel... |
3200832 | Non-heme protein in the giant extracellular hemoglobin of the earthworm Lumbricus terrestris. | The protein/heme mass ratio for the extracellular hemoglobin of the earthworm Lumbricus terrestris has been redetermined. We find a value of 19,000 g of protein per mol of heme. Four major, heme-containing chains (a, b, c, and d), present in equal proportions, have a total molecular mass, with four hemes, of 69,664 Da ... |
2849104 | Analysis of temperature-sensitive mutations in the simian virus 40 gene encoding virion protein 1. | Temperature-sensitive (ts) assembly mutants of the tumorigenic virus simian virus 40 (SV40) fail to follow the normal pathway of virion morphogenesis at 40 degrees C. The mutations were previously mapped to the gene coding for the major virion protein VP1 and fall into three groups: tsB, tsBC, and tsC. We have determin... |
2849050 | Picrate and niflumate block anion modulation of radioligand binding to the gamma-aminobutyric acid/benzodiazepine receptor complex. | The organic anions picrate (2,4,6-trinitrophenol) and niflumate (2-[[3-(trifluoromethyl)phenyl]-amino]-3-pyridinecarboxylate) were examined for their effects on radioligand binding to the gamma-aminobutyric acid (GABA)/benzodiazepine receptor complex. Neither organic anion produced the enhancement of [35S] t-butylbicyc... |
3199194 | Evidence for the transneuronal regulation of cerebellin biosynthesis in developing Purkinje cells. | We have investigated the expression of a unique class of neuropeptides, the cerebellins, in normal and neurodevelopmentally mutant mice. Employing HPLC separation, gas-phase Edman sequencing, and immunocytochemistry, the normal Balb/c mouse cerebellum is shown to contain 2 Purkinje cell-specific neuropeptides, cerebell... |
3058721 | Association of microinjected myosin and its subfragments with myofibrils in living muscle cells. | Purified skeletal muscle myosin was labeled with iodoacetamidofluorescein and microinjected into cultured chick myotubes. The fluorescent myosin analogue became incorporated within 10-15 min after injection, into either periodic (mean periodicity = 2.23 +/- 0.02 micron) bands or apparently continuous fibrillar structur... |
2461945 | Addition of carbohydrate side chains at novel sites on influenza virus hemagglutinin can modulate the folding, transport, and activity of the molecule. | We have constructed and expressed a series of mutant influenza virus hemagglutinins, each containing a new consensus site for glycosylation in addition to the seven sites found on the wild-type protein. Oligosaccharide side chains were added with high efficiency at four of the five novel sites, located on areas of the ... |
3058715 | Integral membrane proteins specific to the inner nuclear membrane and associated with the nuclear lamina. | We obtained a monoclonal antibody (RL13) that identifies three integral membrane proteins specific to the nuclear envelope of rat liver, a major 75-kD polypeptide and two more minor components of 68 and 55 kD. Immunogold labeling of isolated nuclear envelopes demonstrates that these antigens are localized specifically ... |
3198614 | Heparin type IV collagen interactions: equilibrium binding and inhibition of type IV collagen self-assembly. | Interactions between type IV collagen and heparin were examined under equilibrium conditions with rotary shadowing, solid-phase binding assays, and affinity chromatography. With the technique of rotary shadowing and electron microscopy, heparin appeared as thin, short strands and bound to the following three sites: the... |
3195846 | Analysis of multiple organ system failure in trauma and nontrauma patients. | Multiple organ failure (MOF), a syndrome of recent evolution, has resulted from advancements in both surgical and trauma care. A prospective study of organ failure (OF) was conducted for 203 consecutive admissions to the surgical intensive care unit (SICU) between September 1986 and June 1987. Diagnosis, operations, ag... |
2848250 | Characterization of a cDNA clone encoding the calmodulin-binding domain of mouse brain calcineurin. | A cDNA clone corresponding to a portion of the catalytic subunit of calmodulin (CaM)-dependent phosphoprotein phosphatase (calcineurin) was isolated from a murine brain library by expression vector immunoscreening. A beta-galactosidase fusion protein that reacted on Western blots with anti-calcineurin antibodies and bi... |
3142875 | Drosophila basement membrane procollagen alpha 1(IV). II. Complete cDNA sequence, genomic structure, and general implications for supramolecular assemblies. | A Drosophila melanogaster gene for a basement membrane procollagen chain was recently identified from the sequence homology of the carboxyl (NC1) end of the polypeptide that it encodes with the corresponding domain of human and murine collagens IV (Blumberg, B., MacKrell, A. J., Olson, P. F., Kurkinen, M., Monson, J. M... |
3142865 | Isolation of additional monoclonal antibodies directed against cell surface antigens of Myxococcus xanthus cells undergoing submerged development. | Thirteen additional monoclonal antibodies directed against cell surface antigens of Myxococcus xanthus cells undergoing submerged development were isolated and partially characterized. As measured by quantitative enzyme-linked immunosorbent assay, 10 of these antibodies recognized antigens common to both vegetatively g... |
2461359 | Mutations that affect production of branched RNA-linked msDNA in Myxococcus xanthus. | A deletion mutation of the gene (msd-msr) for the branched RNA-linked msDNA of Myxococcus xanthus was constructed by replacing the chromosomal 0.7-kilobase (kb) SmaI-XhoI fragment encompassing msd-msr with a 1.4-kb fragment carrying a gene for kanamycin resistance. It was found that this deletion strain (delta msSX) co... |
2460638 | Complex between glycoproteins gI and gp63 of pseudorabies virus: its effect on virus replication. | To ascertain the biological functions of different glycoproteins that are nonessential for pseudorabies virus growth in vitro, we have constructed mutants defective in one (or a combination) of these glycoproteins and have examined various aspects of their role in the infective process. We made the following two observ... |
3141281 | Loss of transferrin receptor activity in Neisseria meningitidis correlates with inability to use transferrin as an iron source. | Although Neisseria meningitidis does not produce siderophores, it is able to obtain iron from human transferrin. We observed saturable specific binding of 125I-labeled human transferrin to meningococci. Human lactoferrin and mouse transferrin did not compete with human transferrin for binding, whereas human apotransfer... |
3180085 | Late target protein of the carcinogen N-2-fluorenylacetamide in rat liver. | In previous studies, administration of a radioactive tracer dose of the liver carcinogen, N-2-fluorenylacetamide (2-acetylaminofluorene; FAA), to normal or carcinogen-fed rats led to the presence of one or two principal labeled carcinogen: protein complexes in liver cytosol. The early target Mr 14,000 protein of the ca... |
3075439 | Antibacterial action of 2-bromo-2-nitropropane-1,3-diol (bronopol). | Patterns of growth inhibition of Escherichia coli in the presence of 2-bromo-2-nitropropane-1,3-diol (bronopol) indicate a period of biocide-induced bacteriostasis followed by growth at an inhibited rate. The length of the bacteriostatic period, but not the subsequent growth inhibition, was reduced by the addition of e... |
3247276 | Amorphous water-soluble cyclodextrin derivatives: 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxyisobutyl, and carboxamidomethyl derivatives of beta-cyclodextrin. | The pharmaceutical usefulness of natural, crystalline cyclodextrins can be improved by chemical conversions into water-soluble, amorphous mixtures of their derivatives. Reaction of beta-cyclodextrin with 2-chloroethanol, 3-chloropropanol, isobutylene oxide, or iodoacetamide yielded the title compounds. Distributions of... |
3243512 | [Pharmacological studies on the clathrate compound of mobenzoxamine with beta-cyclodextrin. (I). Effects on the digestive system]. | Effects of the clathrate compound of mobenzoxamine (MBX) with beta-cyclodextrin (MBX-CD), a new gastro-intestinal function modulator, on the digestive system were studied in comparison with those of metoclopramide, domperidone and trimebutine. MBX-CD showed inhibitory effects that were approximately 1/4 times as potent... |
3242597 | Time-resolved solution X-ray scattering of tobacco mosaic virus coat protein: kinetics and structure of intermediates. | The kinetics of assembly and disassembly of tobacco mosaic virus coat protein (TMVP) following temperature jumps have been studied by small-angle X-ray scattering and turbidimetry. The structures of the principal aggregates of TMVP oligomers (A protein), intermediate size (helix I) and large size helical rods (helix II... |
3234545 | [The action of cortifen and corticosterone on the thymocyte nucleoid of mice in vivo and in vitro]. | The effect of therapeutic doses of a hormonal cytostatic cortifen and corticosterone on supramolecular DNA structures of mice thymocyte nucleoid was studied. Capillary elastoviscometry showed that in vivo damage to supramolecular DNA complex structure there was a difference already two hours after injection of these ag... |
2976684 | [Mechanism of the vascular action of verapamil and a crown ether derivative]. | The effects of verapamil and benzyl-aza-15-crown-5 on pressor reactions of blood pressure and perfusion pressure in the femoral artery after administration of noradrenaline, tyramine, angiotensin amide and stimulation of the femoral nerve were studied in acute experiments on anesthetized cats (pentobarbital sodium, 50 ... |
3225761 | Improved delivery through biological membranes. XXXL: Solubilization and stabilization of an estradiol chemical delivery system by modified beta-cyclodextrins. | A dihydropyridine in equilibrium pyridinium salt chemical delivery system (CDS) for estradiol (E2CDS) was complexed with various modified beta-cyclodextrins including hydroxyethyl-beta-cyclodextrin (HECD), hydroxypropyl-beta-cyclodextrin (HPCD), and heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DMCD). Complex formation ... |
3066684 | Isolation and characterization of conditional-lethal mutations in the TUB1 alpha-tubulin gene of the yeast Saccharomyces cerevisiae. | Microtubules in yeast are functional components of the mitotic and meiotic spindles and are essential for nuclear movement during cell division and mating. We have isolated 70 conditional-lethal mutations in the TUB1 alpha-tubulin gene of the yeast Saccharomyces cerevisiae using a plasmid replacement technique. Of the ... |
2975762 | Molecular recognition of antibody (IgG) by cellular Fc receptor (FcRI). | Earlier studies from this and other laboratories have provided indirect evidence for the involvement of the C gamma 2 domain of human IgG in the binding of IgG to the high affinity monocyte Fc receptor (FcRI). Two approaches have been used to extend these studies and to further localize the site of interaction on human... |
3145712 | Transformation of tetrachloromethane to dichloromethane and carbon dioxide by Acetobacterium woodii. | Five anaerobic bacteria were tested for their abilities to transform tetrachloromethane so that information about enzymes involved in reductive dehalogenations of polychloromethanes could be obtained. Cultures of the sulfate reducer Desulfobacterium autotrophicum transformed some 80 microM tetrachloromethane to trichlo... |
3145251 | Conformational studies on host-guest peptides containing chiral alpha-methyl-alpha-amino acids. Comparison of the helix-inducing potential of alpha-aminoisobutyric acid, (S)-2-ethylalanine and (S)-2-methylserine. | The conformational behaviour of host-guest peptides of the type Ac-Ala-Xxx-Ala-Ala-Xxx-Ala-Ala-Xxx-Ala-Ala-NH-PEGM (Xxx = alpha-aminoisobutyric acid (Aib), (S)-2-ethylalanine ((S)-Iva), (S)-2-methylserine ((S)-alpha-MeSer)) has been studied by CD spectroscopy in CF3CH2OH, CH3OH, and water and by i.r. spectroscopy in CH... |
2850169 | The gamma delta resolvase bends the res site into a recombinogenic complex. | We have characterized complexes between the gamma delta resolvase and its recombination site, res, using both a gel retardation assay and DNase I cleavage. The mobility of resolvase-res complexes in polyacrylamide gels is sensitive to the location of res within the DNA fragment and is at a minimum when res is at its ce... |
2463164 | A model for the spatial arrangement of the proteins in the large subunit of the Escherichia coli ribosome. | A three-dimensional model for the arrangement of 29 of the 33 proteins from the Escherichia coli large ribosomal subunit has been generated by interactive computer graphics. The topographical information that served as input in the model building process was obtained by combining the immunoelectron microscopically dete... |
3205257 | [A review of post-operative multiple organ failure in peripheral arterial diseases]. | Two-hundred- and-fifty-one patients of peripheral arterial diseases underwent 281 operations for past 11 years in our institute, and multiple organ failure (MOF) occurred in 10 patients (4.0%). These patients were reviewed and were compared with in other diseases. Survival rate was 50% and all the patients with 4 or mo... |
3196735 | Rapid and slow hydroxylators of seminal E prostaglandins. | Human seminal fluid contains prostaglandin (PG) E1, PGE2, 19-hydroxy-PGE1 and 19-hydroxy-PGE2 in large and variable amounts. 19-Hydroxy-PGE1 and 19-hydroxy-PGE2 are formed from PGE1 and PGE2 by prostaglandin 19-hydroxylase, a cytochrome P-450 enzyme, in seminal vesicles. The hypothesis that genetic polymorphism of this... |
2461545 | Measurement of poliovirus RNA polymerase binding to poliovirion and nonviral RNAs using a filter-binding assay. | The binding of the purified poliovirus RNA-dependent RNA polymerase to viral and nonviral RNAs was studied using a protein-RNA nitrocellulose filter binding assay. A cellular poly(A)-binding protein was found in viral polymerase preparations, but was easily separated from the polymerase by chromatography on poly(A) Sep... |
2848217 | Effects of VM26, a specific inhibitor of type II DNA topoisomerase, on SV40 chromatin replication in vitro. | We have examined the influence of VM26 (teniposide), a specific inhibitor of mammalian type II DNA topoisomerase, on the replication of SV40 minichromosomes in vitro. The replication system we used consists of replicative intermediate SV40 chromatin as substrate which is converted to mature SV40 chromatin in the presen... |
3186702 | Structure of the reaction center from Rhodobacter sphaeroides R-26 and 2.4.1: protein-cofactor (bacteriochlorophyll, bacteriopheophytin, and carotenoid) interactions. | The three-dimensional structures of the cofactors and protein subunits of the reaction center (RC) from the carotenoidless mutant strain of Rhodobacter sphaeroides R-26 and the wild-type strain 2.4.1 have been determined by x-ray diffraction to resolutions of 2.8 A and 3.0 A with R values of 24% and 26%, respectively. ... |
2847148 | Negative and positive factors determine the activity of the polyoma virus enhancer alpha domain in undifferentiated and differentiated cell types. | The host range of polyoma virus is dependent upon the activity of its enhancer, which is inactive in undifferentiated embryonal carcinoma cells, such as F9 cells, and is active after their differentiation. We show here that the activity of the alpha domain of the polyoma virus enhancer displays a similar cell-specifici... |
3186693 | Covalent binding of the endogenous estrogen 16 alpha-hydroxyestrone to estradiol receptor in human breast cancer cells: characterization and intranuclear localization. | The interactions of 16 alpha-hydroxyestrone (16 alpha-OHE1), a metabolite of estradiol (E2), with estrogen receptors (ERs) were compared in this study to the classic E2-receptor mechanism in human breast cancer cells MCF-7 in culture. When MCF-7 cells were incubated with radioinert 16 alpha-OHE1 or its 3H-labeled form ... |
3183059 | Distinct murine macrophage receptor pathway for human triglyceride-rich lipoproteins. | Murine P388D1 macrophages have a receptor pathway that binds human hypertriglyceridemic very low density lipoproteins (HTG-VLDL) that is fundamentally distinct from the LDL receptor pathway. Trypsin-treated HTG-VLDL (tryp-VLDL), devoid of apolipoprotein (apo)-E, fail to bind to the LDL receptor, yet tryp-VLDL and HTG-V... |
3141380 | Acceleration of starvation- and glycerol-induced myxospore formation by prior heat shock in Myxococcus xanthus. | The effect of heat shock on Myxococcus xanthus was investigated during both glycerol- and starvation-induced development. Cells heat shocked at 40 degrees C for 1 h prior to a development-inducing signal displayed an accelerated rate of myxospore formation at 30 degrees C. Additionally, M. xanthus cells heat shocked pr... |
2845147 | Increased expression of CD4 molecules on Jurkat cells mediated by human immunodeficiency virus tat protein. | The tat gene of the human immunodeficiency virus, tat-III, when introduced into T-lymphoblastoid Jurkat cells by a Moloney retroviral recombinant DNA vector expressed high levels of the functional tat protein as measured by the chloramphenicol acetyltransferase assay. Immunofluorescence analysis with CD4-specific monoc... |
2845141 | Specific interaction between coronavirus leader RNA and nucleocapsid protein. | Northwestern blot analysis in the presence of competitor RNA was used to examine the interaction between the mouse hepatitis virus (MHV) nucleocapsid protein (N) and virus-specific RNAs. Our accompanying article demonstrates that anti-N monoclonal antibodies immunoprecipitated all seven MHV-specific RNAs as well as the... |
2845140 | Interactions between coronavirus nucleocapsid protein and viral RNAs: implications for viral transcription. | The interaction of the mouse hepatitis virus (MHV) nucleocapsid protein (N) and viral RNA was examined. Monoclonal antibody specific for N protein coimmunoprecipitated MHV genomic RNA as well as all six MHV subgenomic mRNAs found in MHV-infected cells. In contrast, monoclonal antibodies to the MHV E2 or E1 envelope gly... |
19431734 | Dehydration-induced molecular structural changes of purple membrane of halobacterium halobium. | The nature and extent of dehydration-induced molecular structural changes of the purple membrane of Halobacterium halobium have been studied by absorption and circular dichroism spectra in solution and in oriented membrane films. High glycerol concentrations, exhaustive dry nitrogen gas flushing, and exhaustive high-va... |
16593991 | Infrared spectroelectrochemistry of bacteriochlorophylls and bacteriopheophytins: Implications for the binding of the pigments in the reaction center from photosynthetic bacteria. | The IR spectra of the bacteriochlorophyll a and b cations and the bacteriopheophytin a and b anions were obtained by using an IR and optically transparent electrochemical cell. Prominent effects of radical formation on the vibrational spectra were found for bands assigned to the ester, keto, and acetyl C=O groups and f... |
16347785 | Purification and Characterization of Thermostable Pullulanase from Bacillus stearothermophilus and Molecular Cloning and Expression of the Gene in Bacillus subtilis. | A thermostable pullulanase (alpha-dextrin 6-glucanohydrolase [EC 3.2.1.41]) from a newly isolated Bacillus stearothermophilus strain (TRS128) was purified and characterized. The enzyme hydrolyzed (1-->6)-alpha-d-glucosidic linkages of pullulan to produce maltotriose, and the optimum temperature was 65 degrees C. About ... |
3243857 | High-performance liquid chromatography separations of nitrosamines. III. Conformers of N-nitrosamino acids. | The separation of a selected group of N-nitrosamino acids and their syn and anti conformers by high-performance liquid chromatography using an alpha-cyclodextrin bonded silica gel column and a mobile phase of acetonitrile-triethylammonium acetate was achieved. The effects of mobile phase pH and concentration of acetoni... |
3243848 | Use of hydroxypropyl- and hydroxyethyl-derivatized beta-cyclodextrins for the thin-layer chromatographic separation of enantiomers and diastereomers. | Partially substituted hydroxypropyl-beta-cyclodextrin and hydroxyethyl-beta-cyclodextrin proved to be effective chiral mobile phase additives (CMAs) for the thin-layer chromatographic (TLC) resolution of racemic benzyl-2-oxazolidinone, 5-(4-methyl-phenyl)-5-phenylhydantoin, mephenytoin and several dansyl and beta-napht... |
3241020 | Use of cyclodextrins in isotachophoresis. VI. Cyclodextrins as leading electrolyte additives for the separation of bile acids. | Cyclodextrins (CDs) and some of their methyl derivatives have been used for the optimization of the isotachophoretic separation of bile acids in aqueous electrolyte systems. The addition of heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin to the leading electrolyte proved useful for both the solubilization and the struct... |
2906814 | Pertussis: the disease and new diagnostic methods. | Bordetella pertussis, the causative agent of whooping cough, produces an acute and chronic respiratory infection in infants and young children. B. pertussis is still a major health problem of young children throughout the world even though effective immunization against whooping cough is available. While predominantly ... |
3145981 | Nerve growth factor rapidly stimulates arachidonate metabolism in PC12 cells: potential involvement in nerve fiber growth. | Homogenates prepared from pheochromocytoma (PC12) cells that are extending nerve fibers in response to nerve growth factor (NGF) have an increased capacity to metabolize exogenous arachidonate compared with homogenates prepared from cells untreated with NGF. These changes are not a consequence of cell attachment, since... |
3214206 | [New derivatives of carminomycin and rubomycin]. | For preparing new semisynthetic analogs of anthracycline antibiotics, hydrolysis of 13-dimethylketals of 14-bromrubomycin and 14-brom-arminomycin in solution of diluted hydrochloric acid was studied. It was shown that such hydrolysis yielded 14-chlorrubomycin and 14-chlorcarminomycin. Conditions for separating the mixt... |
3212016 | [The liberation of phenylbutazone from tablets]. | The liberation of phenylbutazone from tablets prepared by wet granulation was examined. It was found that the solution process can be described by the equation c = cs (l-e-K.t alpha). The influence of the binder concentration and the disintegrant on the liberation rate was also studied. The increase of the Klucel MF co... |
3205677 | Effect of cyclodextrins on anthracycline stability in acidic aqueous media. | The effect of cyclodextrins on the stability of six anthracyclines in acidic medium at 50 degrees C has been investigated using a stability-indicating high pressure liquid chromatographic method. The influences of various parameters, such as the structure of cyclodextrins (alpha-cyclodextrin, beta-cyclodextrin, dimethy... |
3196082 | Activation of neutral metalloprotease in human osteoarthritic knee cartilage: evidence for degradation in the core protein of sulphated proteoglycan. | The neutral, metal dependent, proteoglycan degrading enzymes (NMPEs) in human osteoarthritic knee cartilage homogenates were activated by p-aminophenylmercuric acetate (APMA). The resultant effect on the structure of newly synthesised and already existing sulphated proteoglycan was measured. Newly synthesised and alrea... |
2848380 | Controlled organization of multimolecular complexes of enveloped virus glycoproteins: study of immunogenicity. | Some technological and immunological problems facing the preparation of subunit viral vaccines are discussed. Solubilization of enveloped virus glycoproteins with various detergents has been studied. It has been demonstrated that a novel non-ionic detergent, MESK, can be used to prepare the glycoproteins of enveloped v... |
3190488 | Prognostic value of serum osmolality gap in patients with multiple organ failure treated with hemopurification. | Serum osmolality gap (OG), the difference between measured and predicted serum osmolality, has been shown to be an excellent parameter to express the amount of conventionally unmeasurable middle-molecular-weight substances. OG was determined on 29 patients with multiple organ failure (MOF) treated with or without hemop... |
2847033 | The C proteins of heterogeneous nuclear ribonucleoprotein complexes interact with RNA sequences downstream of polyadenylation cleavage sites. | The heterogeneous nuclear ribonucleoprotein C1 and C2 proteins were preferentially cross-linked by treatment with UV light in nuclear extracts to RNAs containing six different polyadenylation signals. The domain required for the interaction was located downstream of the poly(A) cleavage site, since deletion of this seg... |
3181126 | Amino acid sequences and homopolymer-forming ability of the intermediate filament proteins from an invertebrate epithelium. | Intermediate filaments (IF) isolated from the oesophagus epithelium of the snail Helix pomatia contain two polypeptides of mol. wt 66,000 (A) and 52,000 (B), which we have now characterized by in vitro self-assembly studies and by protein sequences. A and B can each form morphologically normal IF and share extended reg... |
3263169 | Sprouting of CGRP nerve fibers in response to dentin injury in rat molars. | Light and electron microscopic immunocytochemistry showed extensive increases in the number of calcitonin gene-related peptide immunoreactive (CGRP-IR) nerve fibers subjacent to injured root dentin of rat molars. Sprouting was greatest at 4 days and returned to normal 10-21 days post injury. Non-CGRP-IR fibers were als... |
3174662 | Hemagglutinin polymorphism as the basis for low- and high-yield phenotypes of swine influenza virus. | Single amino acid substitutions at the rim of the receptor binding site of the hemagglutinin molecule of swine influenza virus markedly influence the replicative capacity of the virus in chicken embryos, Madin-Darby canine kidney cells (MDCK), and swine as well as its antigenic phenotype. Mutants of low-yield (L) pheno... |
3174658 | Peroxisomal lignoceroyl-CoA ligase deficiency in childhood adrenoleukodystrophy and adrenomyeloneuropathy. | We previously reported that in childhood adrenoleukodystrophy (C-ALD) and adrenomyeloneuropathy (AMN), the peroxisomal beta-oxidation system for very long chain (greater than C22) fatty acids is defective. To further define the defect in these two forms of X chromosome-linked ALD, we examined the oxidation of [1-14C]li... |
3051000 | Electron transfer in a genetically modified bacterial reaction center containing a heterodimer. | Time-resolved optical measurements encompassing the femtoseconds to seconds time scales have been used to investigate Rhodobacter capsulatus reaction centers (RCs) in which the histidine residue at position 200 on the M polypeptide has been changed to a leucine by site-directed mutagenesis. The HisM200----Leu RC, which... |
3050999 | Cloning and nucleotide sequence of the gene for dihydrolipoamide acetyltransferase from Saccharomyces cerevisiae. | A 537-base cDNA encoding a portion of Saccharomyces cerevisiae dihydrolipoamide acetyltransferase (acetyl-CoA:dihydrolipoamide S-acetyltransferase, EC 2.3.1.12) was isolated from a lambda gt11 yeast cDNA library by immunoscreening. This cDNA was subcloned and used as a probe to screen a lambda gt11 yeast genomic DNA li... |
3174627 | Modeling of the bryostatins to the phorbol ester pharmacophore on protein kinase C. | The bryostatins are macrocyclic lactones that represent an additional structural class of potent activators of protein kinase C. These marine animal biosynthetic products are of unusual interest because they induce only a subset of the biological responses induced by the phorbol esters. We have now determined the bindi... |
3170749 | Reversibility of defective adipocyte insulin receptor kinase activity in non-insulin-dependent diabetes mellitus. Effect of weight loss. | Insulin-stimulated kinase activity of adipocyte-derived insulin receptors is reduced in subjects with non-insulin-dependent diabetes mellitus (NIDDM) but normal in obese nondiabetics. To assess the reversibility of the kinase defect in NIDDM, insulin receptor kinase activity was measured before and after weight loss in... |
2459133 | High resolution immunoelectron microscopic localization of functional domains of laminin, nidogen, and heparan sulfate proteoglycan in epithelial basement membrane of mouse cornea reveals different topological orientations. | Thin and ultrathin cryosections of mouse cornea were labeled with affinity-purified antibodies directed against either laminin, its central segments (domain 1), the end of its long arm (domain 3), the end of one of its short arms (domain 4), nidogen, or low density heparan sulfate proteoglycan. All basement membrane pr... |
3170635 | Dynamic instability of individual microtubules analyzed by video light microscopy: rate constants and transition frequencies. | We have developed video microscopy methods to visualize the assembly and disassembly of individual microtubules at 33-ms intervals. Porcine brain tubulin, free of microtubule-associated proteins, was assembled onto axoneme fragments at 37 degrees C, and the dynamic behavior of the plus and minus ends of microtubules wa... |
3049620 | Functions of microtubules in the Saccharomyces cerevisiae cell cycle. | We used the inhibitor nocodazole in conjunction with immunofluorescence and electron microscopy to investigate microtubule function in the yeast cell cycle. Under appropriate conditions, this drug produced a rapid and essentially complete disassembly of cytoplasmic and intranuclear microtubules, accompanied by a rapid ... |
2459127 | A monoclonal antibody against the nuclear pore complex inhibits nucleocytoplasmic transport of protein and RNA in vivo. | A monoclonal antibody that reacts with proteins in the nuclear pore complex of rat liver (Snow, C. M., A. Senior, and L. Gerace. 1987. J. Cell Biol. 104:1143-1156) has been shown to cross react with similar components in Xenopus oocytes, as determined by immunofluorescence microscopy and immunoblotting. We have microin... |
3139640 | Localization of the cis-acting regulatory DNA sequences of the Myxococcus xanthus tps and ops genes. | The cis-acting regulatory regions of the tps and ops genes of Myxococcus xanthus were localized by analyzing the expression of fusions of these genes with the lacZ gene. A 201-base-pair (bp) fragment of tps DNa extending 95 bp upstream (-95) from the transcriptional start was sufficient to direct developmentally regula... |
3049549 | Activation of protease-constitutive recA proteins of Escherichia coli by all of the common nucleoside triphosphates. | To understand why the RecA proteins of the protease-constitutive recA1202 and recA1211 mutants show very high protease activities in vivo without the usual need for DNA damage (E. S. Tessman and P. Peterson, J. Bacteriol. 163:677-687, 1985), we examined the activation of the mutant proteins by nucleoside triphosphates ... |
3049545 | Transcriptional analysis of the major surface array gene of Caulobacter crescentus. | The major component of the paracrystalline surface array of Caulobacter crescentus CB15 and one of the most abundant cellular proteins is a protein designated 130K. We have determined the DNA sequence of the 5' portion of the 130K gene, including the N-terminal one-third of the protein coding region, and analyzed the t... |
3049532 | Two regions of mature periplasmic maltose-binding protein of Escherichia coli involved in secretion. | Six mutations in malE, the structural gene for the periplasmic maltose-binding protein (MBP) from Escherichia coli, prevent growth on maltose as a carbon source, as well as release of the mutant proteins by the cold osmotic-shock procedure. These mutations correspond to insertion of an oligonucleotide linker, concomita... |
18964624 | Anodic stripping voltammetric determination of trace lead with a nafion/crown-ether film electrode. | An electrode for the anodic stripping voltammetric determination of trace lead has been made by coating glassy carbon with a film of Naflon in which a crown ether is incorporated. The sensitivity is increased because of continuous transfer of lead from solution to the electrode surface by complexation with the crown et... |
18964615 | A comparative study of the effect of o-nitrophenyl octyl ether and o-nitrophenyl pentyl ether as plasticizers on the response and selectivity of carrier-based liquid membrane ion-selective electrodes. | Lithium, potassium and caesium-selective microelectrodes were prepared by coating the tips of preconditioned silver wires, incorporated in a flow-cell, with PVC membranes containing four different ionophores. A dicarboxamide, a 14-crown-4 carboxylic acid, benzo-18-crown-6 and di-(tert-butylbenzo)-21-crown-7 ionophores ... |
3243840 | Planar chromatographic separation of enantiomers and diastereomers with cyclodextrin mobile phase additives. | A variety of racemic compounds were resolved using reversed-phase thin-layer chromatography (TLC) with mobile phases containing highly concentration solutions of beta-cyclodextrin (beta-CD). These include the drugs labetalol and mephenytoin, metallocenes, crown ethers, methyl-p-toluenesulfinate, nornicotine derivaties ... |
3240986 | Intermolecular interactions between protein and other molecules including hydration effects. | The structural aspects of protein functions, e.g., molecular recognition such as enzyme-substrate and antibody-antigen interactions, are elucidated in terms of dehydration and atomic interactions. When a protein interacts with some target molecule, water molecules at the interacting regions of both molecules are remove... |
3070546 | Apomyoglobin as a molecular recognition surface: expression, reconstitution and crystallization of recombinant porcine myoglobin in Escherichia coli. | Recombinant porcine myoglobin has been produced in Escherichia coli using the lambda cII fusion expression system of Nagai and Thøgersen [Nature, 309, 810-812 (1984)]. After processing and reconstitution with haem, the protein is gel-electrophoretically and spectrophotometrically indistinguishable from native pig myogl... |
3237685 | Structural models of the evolutionarily conservative central domain of silk-moth chorion proteins. | Silk-moth chorion proteins belong to a small number of families: A, B, C, Hc-A and Hc-B. The central domain is an evolutionarily conservative region in each family, of variable length and composition between families. This domain shows clear 6-fold periodicities for various amino acid residues, e.g. glycine. The period... |
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