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1817607 | Heavy-meromyosin-decorated actin filaments: a simple method to preserve actin filaments for rotary shadowing. | It has become accepted that deep-freeze-drying at or below -90 degrees C is necessary to preserve the structure of supramolecular assemblies such as actin filaments (AFs) for metal shadowing. This has kept the metal shadowing technique from widespread use in the study of proteins complexed with AFs because of the limit... |
1813244 | [Experimental study of the murine monoclonal antibodies of anti-human osteogenic sarcoma]. | In the present experiment, cellular suspension, extracted from osteogenic sarcoma tissue removed from patients in operation, was used to immunize BABL/cmouse. The immunized murine spleen cells and murine myeloma cells were fused. The three lines of the hybridoma cells were produced by fusion and were screened by the me... |
1797438 | Separation and characterization of three positional isomers of dimaltosyl-cyclomaltoheptaose (dimaltosyl-beta-cyclodextrin). | A mixture of maltosylcyclomaltoheptaoses (maltosyl-beta-cyclodextrins, G2-beta CDs) was prepared from maltose and beta-cyclodextrin (beta CD) through the reverse action of Klebsiella pneumoniae pullulanase. Three positional isomers of dimaltosyl-beta CD in the mixture were separated by high-performance liquid chromatog... |
1795178 | Structural investigations and modeling of cavities in clathrates. | A molecular-graphics study has been performed in order to build and visualize the shape of cavities within different clathrates from X-ray diffraction data [e.g. Dianin's compound, Werner complexes Ni(SCN)2(3-methylpyridine)4, Fe(acetylacetonate)3 and Ni(ethylxanthate)2(4,4'-dimethyl-2,2'-bipyridyl) complexes]. The alg... |
1786577 | Characterization of five isomers of branched cyclomaltoheptaose (beta CD) having degree of polymerization (d.p.) = 9: Reinvestigation of three positional isomers of diglucosyl-beta CD. | It has been confirmed by methylation analyses and chemical syntheses that three isomers of branched cyclomaltoheptaose (beta CD) isolated from the mother liquors of a large-scale preparation of beta CD with Bacillus ohbensis cyclomaltodextrin glucanotransferase are 6(1),6(4)-di-O-(alpha-D-glucopyranosyl)-cyclomaltohept... |
1780356 | Sites and efficacy of photodamage by tin etiopurpurin in vitro using different delivery systems. | Photosensitization by tin etiopurpurin (SnET2) was determined in cell culture using sensitizer dissolved in ethanol or solubilized via three different delivery systems: Cremophor EL, gamma-cyclodextrin or Molecusol (a more water-soluble cyclodextrin derivative). Sensitizer uptake was substantially more efficient when t... |
1780354 | Demonstration that phosphorescent 6-bromo-2-naphthyl sulfate can be used to probe heme accessibility in heme proteins. | The phosphorescence properties of 6-bromo-2-naphthyl sulfate (BNS) in aqueous solution were studied. The phosphorescence lifetime is several hundred microseconds and is self-quenched. Although a fluorescent photoproduct is formed from BNS, it does not interfere with the decay properties of triplet-state BNS and its uti... |
1777433 | Three-dimensional reconstruction of innermost chorion layer of Drosophila grimshawi and Drosophila melanogaster eggshell mutant fs(1)384. | A low-resolution three-dimensional structure of the crystalline innermost chorionic layer (ICL) of the Hawaiian species Drosophila grimshawi and the Drosophila melanogaster eggshell mutant fs(1)384 has been calculated from electron microscope images of tilted negatively stained specimens. The isolated ICL of Drosophila... |
1663372 | Molecular recognition and targeting of lysosomal proteins. | Recent studies have established that in mammalian cells insulin-like growth factor-II can couple the large mannose-6-phosphate receptor to a GTP-binding protein and that the insulin-like growth factor-II-induced activation of the GTP-binding protein is inhibited by mannose-6-phosphate and lysosomal enzymes. In mouse, t... |
1770007 | Isolation and ultrastructural analysis of microfibrillar structures from foetal bovine elastic tissues. Relative abundance and supramolecular architecture of type VI collagen assemblies and fibrillin. | Extensive intact assemblies of matrix macromolecules have been solubilized from foetal calf skin, nuchal ligament and aorta by a new procedure that includes bacterial collagenase digestion under non-reducing, non-denaturing conditions and gel filtration chromatography. Type VI collagen was identified as the major micro... |
1768084 | Carboxylation of o-cresol by an anaerobic consortium under methanogenic conditions. | The metabolism of o-cresol under methanogenic conditions by an anaerobic consortium known to carboxylate phenol to benzoate was investigated. After incubation with the consortium at 29 degrees C for 59 days, o-cresol was transformed to 3-methylbenzoic acid, which was not further metabolized by the consortium. Proteose ... |
17772367 | Molecular recognition at crystal interfaces. | Nucleation, growth, and dissolution of crystals have been studied by stereochemical approach involving molecular recognition at interfaces. A methodology is described for using ;;tailor-made'' additives designed to interact stereospecifically with crystal surfaces during growth and dissolution. This procedure was instr... |
16348543 | Classification and characterization of heterotrophic microbial communities on the basis of patterns of community-level sole-carbon-source utilization. | The BLOLOG redox technology based on tetrazolium dye reduction as an indicator of sole-carbon-source utilization was evaluated as a rapid, community-level method to characterize and classify heterotrophic microbial communities. Direct incubation of whole environmental samples (aquatic, soil, and rhizosphere) in BIOLOG ... |
16348541 | Purification and Properties of a Thermoactive Glucoamylase from Clostridium thermosaccharolyticum. | A bacterial glucoamylase was purified from the anaerobic thermophilic bacterium Clostridium thermosaccharolyticum and characterized. The enzyme, which was purified 63-fold, with a yield of 36%, consisted of a single subunit with an apparent molecular mass of 75 kDa. The purified enzyme was able to attack alpha-1,4- and... |
1752626 | Binding of Cu(2+)-beta-cyclodextrin complex to calf thymus DNA. | Cu(2+)-beta-cyclodextrin (1:1) complex has been found by UV, fluorescence and CD spectroscopy, polarimetry and gel electrophoresis to bind reversibly to calf thymus DNA. Using UV the binding constant was found to be 45280 +/- 7100 M-1. The binding of the complex Cu(2+)-BCD with DNA was stronger than that of free Cu2+. ... |
1721511 | [Active centers of gamma-glutamyltransferase in the aerosol OT reverse micellar system in octane by an inhibitor analysis method]. | Regulation of the supramolecular structure and catalytic activity of the heterodimeric enzyme gamma-glutamyltransferase in the system of Aerosol OT reversed micelles in octane was studied. Variation of the hydration degree causes a reversible dissociation of the enzyme to the light and heavy subunits, both possessing t... |
1956130 | [Analysis of hepatic and renal dysfunction after surgery of thoracic aneurysm]. | To analyze causes of postoperative hepatic and renal dysfunction in patients with thoracic aneurysm, we examined 31 patients who survived surgeries and 2 patients died of MOF. The patients were separated into three groups as follows; Cardiopulmonary bypass (CPB) was used for circulatory support in group A (n = 7), CPB ... |
1367677 | Protein-protein interactions: structural motifs and molecular recognition. | The past year has brought new insights into common structural motifs used for protein-protein interactions by DNA-binding proteins. In addition, there have been significant advances in our understanding of antibody-protein complexes. |
1367676 | Alteration of enzyme specificity and catalysis by protein engineering. | New substrate specificities can be introduced into existing enzymes for the purpose of making them more suitable for the chemoenzymic synthesis of single compound drugs and other chiral compounds. The most productive route used in the past year has involved the utilization of the catalytic and substrate-binding propert... |
1952934 | Effects of carbodiimide structure on the immobilization of enzymes. | A series of water-soluble disubstituted carbodiimides of different structure was tested for enzyme immobilization. In the experiments, a polyacrylamide-type bead polymer possessing carboxylic functional groups was used as support. The enzymes immobilized were aminoacylase (N-acylamino acid amidohydrolase; EC 3.5.1.14),... |
1719139 | Three-dimensional fine structure of cytoskeletal-membrane interactions at nodes of Ranvier. | Cytoskeleton-membrane-extracellular matrix interactions at the node of Ranvier were examined in both central and peripheral axons by combining three different methods for tissue preparation with three different electron microscopic techniques for imaging supramolecular structure. Conventional and three-dimensional high... |
1940976 | Noradrenergic nerve fibers of the rectal mucosa in autonomic disorders: comparison of histochemical study with clinical severity and changes in plasma noradrenaline induced by standing. | A histochemical study was carried out on the rectal mucosae biopsied from 20 patients with autonomic dysfunctions and 13 controls using a catecholamine fluorescent staining method, and the rectal noradrenergic nerve fiber lesions were compared with the severity of autonomic symptoms and disturbance of plasma noradrenal... |
1834144 | The pharmacodynamics and pharmacokinetics of a novel thromboxane receptor blocking drug vapiprost (GR32191) after single intravenous doses in healthy subjects. | 1 The effect of single, serially increasing, intravenous doses of a specific thromboxane receptor blocking drug, vapiprost, upon platelet aggregation induced ex vivo by the thromboxane A2 mimetic, U-46619, was examined in 12 healthy males. 2 Subjects received either 1 (n = 1 subject), 2 (n = 6), 3 (n = 2), or 4 (n = 3)... |
1924158 | Solubilization and stabilization of a benzylpenicillin chemical delivery system by 2-hydroxypropyl-beta-cyclodextrin. | A dihydropyridine----pyridinium salt redox carrier-based chemical delivery system for benzylpenicillin (1) was complexed with 2-hydroxypropyl-beta-cyclodextrin (HPCD). The solubility of the lipophilic 1, which is incompatible with aqueous formulations, was dramatically increased and showed a linear dependency on the HP... |
1912284 | Spinodal lines and Flory-Huggins free-energies for solutions of human hemoglobins HbS and HbA. | Gelation of deoxygenated solutions of sickle-cell human Hemoglobin (HbS) is of high theoretical interest and it has serious pathological consequences. For this reason HbS is probably the most studied protein capable of self-organization. This notwithstanding, the location in the T, c plane of the region of thermodynami... |
1912280 | Near-infrared Fourier transform Raman and conventional Raman studies of calf gamma-crystallins in the lyophilized state and in solution. | We present in this report a detailed structural study of calf gamma-crystallins both in the solid state and in solution by the newly developed technique of near-infrared (IR) Fourier transform (FT)-Raman spectroscopy as well as by the conventional Raman method. In comparison with conventional laser Raman spectroscopy, ... |
1912274 | Electroporation of cell membranes. | Electric pulses of intensity in kilovolts per centimeter and of duration in microseconds to milliseconds cause a temporary loss of the semipermeability of cell membranes, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA. A generally accepted term desc... |
1368710 | Cloning and sequencing of a cyclodextrin glucanotransferase gene from Bacillus ohbensis and its expression in Escherichia coli. | A cyclodextrin glucanotransferase (CGTase) gene of Bacillus ohbensis was cloned in Escherichia coli and the nucleotide sequence was determined. A single open reading frame (2112 bp) with a TTG codon as an initiator was identified that encodes a typical signal peptide of 29 amino acids followed by the mature enzyme (675... |
1898059 | The pH dependence of the action pattern in porcine pancreatic alpha-amylase-catalyzed reaction for maltooligosaccharide substrates. | Porcine pancreatic alpha-amylase (EC 3.2.1.1; abbreviated PPA), which hydrolyzes alpha-D-(1,4) glucosidic bonds in starch and amylose, displays an optimum at pH 6.9 for the majority of substrates. The optimum pH, however, shifted to 5.2 for the hydrolysis of some low molecular substrates (Ishikawa, K., et al., 1990, Bi... |
1716453 | Characteristics and performance of a bispecific F (ab'gamma)2 antibody for delivering saporin to a CD7+ human acute T-cell leukaemia cell line. | We have investigated the efficacy of a F(ab'gamma)2 bispecific antibody (BsAb) with dual specificity for the CD7 molecule in one Fab arm and for the ribosome inactivating protein (rip) saporin in the other arm, for delivering saporin to the acute T-cell leukaemia cell line HSB-2. Saporin titration experiments revealed ... |
1886774 | Stringent integrity requirements for both trans-activation and DNA-binding in a trans-activator, Oct3. | POU-specific and POU-homeo domains of Oct3 were produced in Echerichia coli for characterization of DNA binding to the octamer sequence. POU domain protein including A, B and H domains could bind to the octamer sequence efficiently and specifically, and DNase I footprint analysis gave an indistinguishable protection pa... |
1832217 | Inhibition of the cellular response to interferons by products of the adenovirus type 5 E1A oncogene. | Expression of the E1A oncogene of adenovirus type 5 inhibits the response of interferon (IFN)-inducible constructs to Type I (alpha,beta) and II (gamma) IFNs in transient transfection assays. In human cell lines stably expressing E1A mRNA and protein acquisition of an antiviral state and the induction of a number of ge... |
1652962 | Inhibition of bovine brain calmodulin-dependent cGMP phosphodiesterase by peptide and non-peptide angiotensin receptor ligands. | Inhibition of a purified 60 KDa bovine brain calmodulin-dependent cGMP phosphodiesterase (PDE) was investigated for a number of peptides and non-peptides which are known to bind to angiotensin (ANG) receptors. The peptide antagonists sarilesin and sarmesin had KI = 120 and greater than 200 microM respectively, and the ... |
1679330 | Gene structure of heat shock proteins 61KDa and 12KDa (thermophilic chaperonins) of thermophilic bacterium PS3. | Heat shock proteins 60 (hsp60) and 10 (hsp10) are essential for the formation and restoration of many supramolecular structures. For reconstitution of these structures, we isolated stable hsps of 61kDa and 12kDa, which are similar to hsp60 and hsp10, respectively, from the supernatant fraction of thermophilic bacterium... |
1883326 | Link protein as a monitor in situ of endogenous proteolysis in adult human articular cartilage. | The link protein components of proteoglycan aggregates in adult human articular cartilage show heterogeneity due to proteolysis. Cleavages near the N-terminus of the intact link proteins, before residues 17, 19 and 24, generate three proteins of slightly diminished size (LP3). Cleavages within the N-terminal disulphide... |
1879544 | Supramolecular structure of the recombinant murine small heat shock protein hsp25. | The size and shape of the recombinant murine small heat shock protein, hsp25, have been analyzed by hydrodynamic and electron microscopic methods. According to these studies recombinant hsp25 exists in large complexes with a sphere-like shape and diameters of 15-18 nm. The molecular mass of these complexes amounts to a... |
1908789 | Two lipoyl domains in the dihydrolipoamide acetyltransferase chain of the pyruvate dehydrogenase multienzyme complex of Streptococcus faecalis. | A fragment of DNA incorporating the gene, pdhC, that encodes the dihydrolipoamide acetyltransferase (E2) chain of the pyruvate dehydrogenase multienzyme complex of Streptococcus faecalis was cloned and a DNA sequence of 2360 bp was determined. The pdhC gene (1620 bp) corresponds to an E2 chain of 539 amino acid residue... |
1651513 | Elevated urinary leukotriene E4 excretion in patients with ARDS and severe burns. | Increased synthesis of peptidoleukotrienes may occur in a variety of inflammatory diseases. To test this theory, hospitalized patients with a variety of diseases were studied and urine LTE4 quantitated as an index of total body peptidoleukotriene synthesis. 10 patients with ARDS, 7 of which had additional organ involve... |
1650459 | Effect of intron A from human cytomegalovirus (Towne) immediate-early gene on heterologous expression in mammalian cells. | A 2.4 kb fragment of hCMV (Towne strain), containing the 5' end of the major immediate-early gene, has been cloned, sequenced, and used to construct a series of mammalian cell expression plasmids. The effects of regulatory regions present on this fragment were assessed using human glycoproteins as reporter molecules. W... |
1859373 | Down-regulation of mannose receptors on macrophages after infection with Leishmania donovani. | Macrophages express a mannose-specific endocytosis receptor that binds and internalizes mannose-terminated glycoproteins. Infection of mouse peritoneal macrophages with Leishmania donovani resulted in a decrease in mannose-receptor activity. With 125I-labelled beta-glucuronidase as ligand, a 2-fold decrease in uptake r... |
1859364 | Molecular comparisons of the beta 2-microglobulin-binding site in class I major-histocompatibility-complex alpha-chains and proteins of related sequences. | beta 2-Microglobulin (beta 2m) binds non-covalently to the alpha 1, alpha 2 and alpha 3 domains of the alpha-chain of Class I major-histocompatibility-complex (MHC) molecules. On the basis of the crystal structures of human leucocyte antigens HLA-A2.1 and HLA-Aw68.1, we have used molecular-graphics analyses to define 4... |
1856871 | Molecular recognition. Conformational analysis of limited proteolytic sites and serine proteinase protein inhibitors. | The conformations of known tryptic limited proteolytic sites have been analysed and compared to the structures of the binding regions of serine proteinase inhibitors, as they are found when complexed to a serine proteinase. Conformational parameters studied include main-chain torsion angles, root-mean-square fits, acce... |
1855689 | Biology of pancreatic cancer. | Pancreatic cancer is the fifth leading cause of death from malignant disease in Western society. Apart from the fortunate few patients who present with a resectable small pancreatic adenocarcinoma, conventional treatment offers no hope of cure and has little palliative value. Over the past two decades major steps have ... |
1906739 | A fluorescence lifetime study of virginiamycin S using multifrequency phase fluorometry. | Using multifrequency phase fluorometry, fluorescence lifetimes have been assigned to the different protolytic forms of the antibiotic virginiamycin S. These lifetimes are 0.476 +/- 0.005 ns for the uncharged form, 1.28 +/- 0.2 and 7.4 +/- 0.2 ns for the zwitterionic form, 1.19 +/- 0.01 ns for the negatively charged for... |
1854627 | Changes in tumour morphology with alterations in oxygen availability: further evidence for oxygen as a limiting substrate. | The ability of cancer cells to survive at a distance from blood vessels should be dependent on the local supply of nutrients to each vessel. The corded growth of tumour cells around blood vessels within regions of necrosis in the RH carcinoma in the mouse allows the limit to which cells can be supported by individual v... |
1713052 | Multiple epitopes of the human ovarian cancer antigen 14C1 recognised by human IgG antibodies: their potential in immunotherapy. | We have defined a novel ovarian cancer-associated membrane antigen, 14C1, using human monoclonal antibodies derived by EBV-transformation of in situ sensitised patients' B-cells. The pattern of recognition of this antigen by these antibodies suggests that at least three epitopes are discernable. These antibodies can be... |
1854331 | Lipoylation of the E2 components of the 2-oxo acid dehydrogenase multienzyme complexes of Escherichia coli. | The number of functional lipoyl groups in the dihydrolipoyl acetyltransferase (E2) chain of the pyruvate dehydrogenase multienzyme complex from Escherichia coli has been re-assessed by means of a combination of protein-chemical and mass-spectrometric techniques. (1) After the complex had been treated with N-ethyl[2,3-1... |
1713022 | Unexpected immunoreactivities of intermediate filament antibodies in human brain and brain tumors. | Immunoreactivities of 35 different monoclonal antibodies (MAbs) that detect intermediate filaments were studied systematically on serial cryostat sections of 14 well-defined human gliomas (five astrocytomas, three oligodendrogliomas, six glioblastomas) and on normal brain. Glial fibrillary acidic protein (GFAP), viment... |
1853202 | Solution structures of beta peptide and its constituent fragments: relation to amyloid deposition. | The secondary structures in solution of the synthetic, naturally occurring, amyloid beta peptides, residues 1 to 42 [beta (1-42)] and beta (1-39), and related fragments, beta (1-28) and beta (29-42), have been studied by circular dichroism and two-dimensional nuclear magnetic resonance spectroscopy. In patients with Al... |
1906607 | A set of viral DNA decamers enriched in transcription control signals. | We studied the frequency distribution of oligonucleotides 10 bp long in a sample of 620 Kb of viral genomes, containing 102 sequences from GenBank, with the aim of detecting transcription control signals. Two thousand three hundred decamers had a frequency 10 times higher than the mean and were subjected to further sta... |
2069559 | Conformational space of alpha 1-4 glycosidic linkage: a molecular dynamics study. | Molecular Dynamics simulations have been carried out for 100 ps on crystal structure of beta-cyclodextrin in vacuo and with explicit inclusion of solvent at constant pressure and constant temperature using the GROMOS MD algorithm, with a time step of 0.005 ps. The conformational space of the glycosidic linkage was stud... |
2068091 | Anionic subsites of the catalytic center of acetylcholinesterase from Torpedo and from cobra venom. | A peptide of acetylcholinesterase (AcChoEase; acetylcholine acetylhydrolase, EC 3.1.1.7) from the venom of the cobra Naja naja oxiana labeled by the affinity reagent N,N-dimethyl-2-phenylaziridinium (DPA) has been identified. The sequence is Gly-Ala-Glu-Met-Trp-Asn-Pro-Asn. In AcChoEase from Torpedo californica, a homo... |
1712476 | Heparin stimulates epidermal growth factor receptor-mediated phosphorylation of tyrosine and threonine residues. | We have described previously that in extracts of A431 cells epidermal growth factor (EGF) stimulates the phosphorylation of tyrosine as well as of threonine residues in the EGF receptor and in lipocortin 1. We now report that heparin at low concentrations also stimulates the autophosphorylation of the EGF receptor and ... |
1712395 | Novel non-nucleoside inhibitors of HIV-1 reverse transcriptase. 1. Tricyclic pyridobenzo- and dipyridodiazepinones. | Novel pyrido[2,3-b][1,4]benzodiazepinones (I), pyrido[2,3-b][1,5]benzodiazepinones (II), and dipyrido[3,2-b:2',3'-e][1,4]diazepinones (III) were found to inhibit human immunodeficiency virus type 1 (HIV-1) reverse transcriptase in vitro at concentrations as low as 35 nM. In all three series, small substituents (e.g., m... |
2066985 | Synthesis and in vivo photodynamic activity of some bacteriochlorin derivatives against bladder tumors in rodents. | Bacteriochlorins have been suggested as potential photosensitizers for use in photodynamic therapy. We have shown that bacteriochlorin-like macrocycles can be generated through cyclization of either 5,10- or 5,15-bis[(ethoxycarbonyl)vinyl]porphyrins; however, the resulting products are rapidly decomposed on exposure to... |
1648401 | Ni(II) and Ni(I) forms of pentaalkylamide derivatives of cofactor F430 of Methanobacterium thermoautotrophicum. | A series of pentaalkylamide forms of F430 and of its 12,13-diepimer have been generated and characterized. Carbodiimide-assisted N-hydroxysulfosuccinimide activation of all five peripheral carboxylates of the F430 macrocycle allows nucleophilic attack by a number of primary amines (RNH2, R- = CH3-, CH3CH2-, CF3CH2-, CH... |
2061294 | Cloning, nucleotide sequence, and enzymatic characterization of an alpha-amylase from the ruminal bacterium Butyrivibrio fibrisolvens H17c. | A Butyrivibrio fibrisolvens amylase gene was cloned and expressed by using its own promoter on the recombinant plasmid pBAMY100 in Escherichia coli. The amylase gene consisted of an open reading frame of 2,931 bp encoding a protein of 976 amino acids with a calculated Mr of 106,964. In E. coli(pBAMY100), more than 86% ... |
1676398 | Fragmentation of Escherichia coli type 1 fimbriae exposes cryptic D-mannose-binding sites. | Cells of the gram-negative bacterium Escherichia coli are able to attach to various host cells by means of a mannose-specific adhesin associated with type 1 fimbriae. Here we show that fragmentation of type 1 fimbriae by freezing and thawing results in increased mannose-binding activity as demonstrated by increased hem... |
1711543 | Characterization of keratocalmin, a calmodulin-binding protein from human epidermis. | Using affinity-purified calmodulin-binding proteins from human epidermis we have developed a monoclonal IgM antibody, ROC 129.1, to a human desmosomal calcmodulin-binding protein. This antibody reacts with a submembranous 250-kD protein from human keratinocytes and stains human epidermis in a "cell-surface pattern". Pe... |
2056120 | 150-kD von Willebrand factor binding protein extracted from human vascular subendothelium is type VI collagen. | We have previously shown that von Willebrand factor (vWF), a glycoprotein which plays a critical role in the adhesion of platelets to injured blood vessels, is present within vascular subendothelium. We investigated the identity of the subendothelial binding site(s) for vWF by examining vWF binding to subendothelial co... |
1904841 | Acquisition of iron by Legionella pneumophila: role of iron reductase. | Legionella pneumophila has been shown to survive and multiply in a variety of intracellular environments, including protozoa and human mononuclear phagocytes. However, the mechanism by which this organism acquires iron in the intracellular environment has not been studied. Since L. pneumophila does not produce sideroph... |
2050127 | Histone-DNA interactions and their modulation by phosphorylation of -Ser-Pro-X-Lys/Arg- motifs. | The sea urchin sperm-specific histones H1 and H2B are multiply phosphorylated in spermatids, dephosphorylated in the final stages of spermatogenesis to give mature sperm, and rephosphorylated upon fertilization. Phosphorylation in spermatids, and probably at fertilization, occurs at repeated -Ser-Pro-X-Basic-motifs in ... |
1645802 | Biochemical and biological differences between E7 oncoproteins of the high- and low-risk human papillomavirus types are determined by amino-terminal sequences. | Differences in the biological characteristics of the high-risk human papillomavirus type 16 (HPV-16) and the low-risk HPV-6 E7 proteins were analyzed and shown to correlate with certain biochemical properties. To ascertain which region of E7 conferred these properties, chimeric E7 genes were constructed by the exchange... |
1674968 | The inability of human immunodeficiency virus to infect chimpanzee monocytes can be overcome by serial viral passage in vivo. | Studies of lentivirus infection in ruminants, nonhuman primates, and humans suggest that virus infection of macrophages plays a central role in the disease process. To investigate whether human immunodeficiency virus type 1 (HIV-1) can infect chimpanzee macrophages, we recovered monocytes from peripheral blood mononucl... |
1710287 | Molecular location of a species-specific epitope on the hamster scrapie agent protein. | Scrapie is a transmissible neurodegenerative disease of sheep and goats. An abnormal host protein, Sp33-37, is the major protein component of the scrapie agent and the only known disease- or agent-specific macromolecule. Two monoclonal antibodies (MAbs), 4H8 (immunoglobulin G2b [IgG2b]) and 6B11 (IgG1), produced by imm... |
1828272 | Role of E2F transcription factor in E1A-mediated trans activation of cellular genes. | Adenovirus E1A-dependent trans activation of the adenovirus E2 gene involves the activation of the cellular transcription factor E2F. E2F binding sites have also been identified in the 5'-flanking region of a number of cellular genes, raising the possibility that such genes are targets for E1A trans activation. We now ... |
1645778 | Mutational analysis of the equine infectious anemia virus Tat-responsive element. | A hairpinlike structure is predicted to exist at the 5' end of equine infectious anemia virus (EIAV) RNA which is similar in many ways to the human immunodeficiency type 1 (HIV-1) Tat-responsive element (TAR). In EIAV, this structure has a shorter stem than in HIV-1 and lacks the uridine bulge. Primer extension analysi... |
1814737 | Pharmacokinetics of dipyridamole-beta-cyclodextrin complex in healthy volunteers after single and multiple doses. | Dipyridamole is a well known anti-aggregating agent characterized by poor water solubility as well as scant and variable bioavailability. Recently, the compound was complexed with beta-cyclodextrin forming a molecular encapsulation resulting in better oral absorption and stronger biological activities in animals. In th... |
1814055 | Acute respiratory distress syndrome--two decades later. | Twenty years have now elapsed since Ashbaugh and Petty first described the syndrome of acute respiratory failure associated with a wide spectrum of clinical conditions. During the past two decades, significant advances have emerged in our understanding of the clinical conditions associated with the syndrome and the pat... |
1813234 | [Rat multiple organ failure model caused by zymosan injections: a pathomorphological study]. | We succeeded in developing a Wistar rat multiple organ failure (MOF) model by intraperitoneal injection of Zymosan. 80 rats were divided into the experimental and control groups. On alternative days (1, 2, 4-5 day), rats were killed after their blood specimens were examined. In the experimental group, changes in PaO2, ... |
1799464 | Evaluation of peptide/metal ion interactions by UV laser desorption time-of-flight mass spectrometry. | A relatively recent method developed to determine the molecular weights of intact peptides and proteins, matrix-assisted UV laser desorption time-of-flight mass spectrometry (LDTOF-MS), has been evaluated as a new means to investigate the metal ion-binding properties of model synthetic peptides. A contiguous sequence o... |
1799463 | Immunomagnetic separation and analysis of non-malignant variants and parental malignant mouse lymphoma cells. | We have devised conditions whereby non-tumorigenic, immunogenic cell variants of S49 mouse lymphoma were analyzed and separated from parental tumorigenic lymphoma cells. This was carried out using polyclonal antibodies (raised against the immunogenic variants) and immunomagnetic beads. The efficacy of the procedure dep... |
1665978 | Peculiarities of recognition of CCA/TGG sequences in DNA by restriction endonucleases MvaI and EcoRII. | To elucidate the mechanism of action of restriction endonucleases MvaI and EcoRII a study was made of their interaction with a set of synthetic substrates in which the heterocyclic bases or the sugar-phosphate backbone had been modified; individual nucleotide residues had been removed or replaced with hydrocarbon bridg... |
1799462 | Identity elements of Escherichia coli tRNA(Ala). | Studies using the T7 transcription system revealed that the discriminator base A73 and the G20 in the variable pocket play important roles in the Escherichia coli alanine tRNA identity. The C60 in the T-loop, which is unique to alanine tRNA, was not found to be crucial for alanine identity. Anticodon replacement into t... |
1799461 | Studies of the binding activity of phage G13 to synthetic trisaccharides analogous to binding structures in Salmonella typhimurium and Escherichia coli C core saccharide. Correlation between conformation and binding activity. | Phage G13 binds to the carbohydrate part of lipopolysaccharides from rough mutants of Salmonella and Escherichia coli as the first event of infection. Equilibrium dialysis inhibition studies with native and synthetic trisaccharides as inhibitors suggested that phage G13 recognizes branched oligosaccharides having 6-O-a... |
1799460 | Binding of the recombinant proteinase inhibitor eglin c from leech Hirudo medicinalis to serine (pro)enzymes: a comparative thermodynamic study. | The binding of the recombinant proteinase inhibitor eglin c from the leech Hirudo medicinalis to serine (pro)enzymes belonging to the chymotrypsin and subtilisin families has been investigated from the thermodynamic viewpoint, between pH 4.5 and 9.5 and from 10 degrees C to 40 degrees C. The affinity of eglin c for the... |
1837987 | Monosaccharides and disaccharides decrease the Km for phosphorylation of a membrane-bound enzyme ATPase. | The disaccharides trehalose and sucrose, and to a lesser extent the monosaccharides glucose and fructose, decrease the apparent Km of the Ca2+, Mg(2+)-ATPase of sarcoplasmic reticulum for Pi. This effect is more pronounced at pH 7.4 than at pH 6.2. The enzyme is not phosphorylated by Pi when the temperature of the medi... |
1929287 | 5'-Alkyl-substituted analogs of 5'-methylthioadenosine as trypanocides. | 5'-Deoxy-5'-(methylthio)adenosine (MTA) is a by-product of polyamine metabolism and is phosphoryolytically cleaved to adenine and 5-deoxy-5-(methylthio)ribose-1-phosphate (MTR-1-P) by MTA phosphorylase. In eukaryotes, adenine is subsequently salvaged and converted to nucleotides, while MTR-1-P is converted to methionin... |
1924150 | Structural effects on the binding of amine drugs with the diphenylmethyl functionality to cyclodextrins. I. A microcalorimetric study. | Solution calorimetry has been employed to evaluate the stability constants and enthalpy changes associated with complex formation between alpha-, beta, or gamma-cyclodextrin (CD) and a group of amine compounds having the diphenylmethyl functionality. Data from thermal titrations of the compounds were analyzed using non... |
1919858 | [Electrophysiological study on pathophysiology of Bell's palsy--distribution of nerve conduction velocities (DNCV) in facial nerve with collision method]. | The etiology of Bell's palsy is still obscure, but the hypothesis that hypoxia and compression of the nerve induced by edema in the Fallopian canal are the main causes of Bell's palsy is widely accepted. Tojima (1988) reported that the motor nerve conduction velocity (MCV) gradually decreased as degeneration of the ner... |
1917032 | Supplemental immunoglobulin (ivIgG) treatment in 163 patients with sepsis and septic shock--an observational study as a prerequisite for placebo-controlled clinical trials. | In a multicenter observational study of 163 medical and surgical patients with a total of 173 episodes of sepsis or septic shock (Elebute sepsis score: 19.0 +/- 0.5), the effects of supplemental i.v. immunoglobulin (i.v. IG) treatment (unmodified polyvalent IgG pH 4.25, n = 123; for Pseudomonas sepsis, n = 50, Pseudomo... |
1889047 | Infectious diseases associated with complement deficiencies. | The complement system consists of both plasma and membrane proteins. The former influence the inflammatory response, immune modulation, and host defense. The latter are complement receptors, which mediate the cellular effects of complement activation, and regulatory proteins, which protect host cells from complement-me... |
1889036 | An epidemiological study of paratuberculosis in dairy cattle in Ontario: study design and prevalence estimates. | An observational study involving 304 dairy herds and three abattoirs was conducted between 1986 and 1989 to investigate the epidemiology of paratuberculosis in dairy cattle in Ontario. The objectives of this paper were to describe the method of data collection for the study, to present descriptive production statistics... |
1886107 | Glycans as biochemical markers of human endometrial secretory differentiation. | Uterine fluid contains a mixture of glycoprotein components the quantity and composition of which vary during the menstrual cycle. Their analysis may give clues to the involvement of maternally derived components in modulating the state of the peri-implantation blastocyst and aid in assessing the differentiation of the... |
1653051 | Vibrational structure of the formyl group on heme a. Implications on the properties of cytochrome c oxidase. | Resonance Raman spectra have been recorded for heme a derivatives in which the oxygen atom of the formyl group has been isotopically labeled and for Schiff base derivatives of heme a in which the Schiff base nitrogen has been isotopically labeled. The 14N-15N isotope shift in the C = N stretching mode of the Schiff bas... |
1881530 | Molecular graphics applied to 5-HT3 ligands. | The recent surge of scientific interest in 5-hydroxytryptamine3 (5-HT3) receptors can be attributed largely to the rapid increase in the number of potent and selective 5-HT3 receptor antagonists. The availability of a large variety of chemically diverse 5-HT3 compounds allows for a unique opportunity to apply computer-... |
1880594 | Determination of the physical structure of biological materials at biosensor interfaces by techniques of increasing magnification from microscopic to molecular scale. | Chemical selectivity of biosensors is derived from biological materials interfaced to the surface of transducing devices. Molecular recognition events lead to macroscopic function suitable for analytical measurements. The structure-function relationships of biochemical species at interfaces must be established to chara... |
1908514 | Injection of inositol trisphosphorothioate into Limulus ventral photoreceptors causes oscillations of free cytosolic calcium. | Limulus ventral photoreceptors contain calcium stores sensitive to release by D-myo-inositol 1,4,5 trisphosphate (InsP3) and a calcium-activated conductance that depolarizes the cell. Mechanisms that terminate the response to InsP3 were investigated using nonmetabolizable DL-myo-inositol 1,4,5 trisphosphorothioate (Ins... |
1873912 | Lipoprotein-cyclodextrin interaction. | Interaction of cyclodextrins with native and isolated lipoproteins was studied by electrophoretic and spectroscopic means. Reaction between these two biomolecules resulted in the formation of soluble and insoluble complexes. Cyclodextrin-mediated precipitation of lipoproteins was strongly affected by the concentration ... |
1873462 | On the relationship between distance information derived from cross-linking and from resonance energy transfer, with specific reference to sites located on myosin heads. | The techniques of fluorescence resonance energy transfer (FRET) and cross-linking can provide complementary information concerning the relative separation of a pair of sites. Cross-linking experiments provide an assessment of the distance of closest approach between a pair of sites. FRET measurements, by contrast, yiel... |
1714353 | Distribution of CGRP-, VIP-, D beta H-, SP-, and NPY-immunoreactive nerves in the periosteum of the rat. | In light of the possible role peripheral nerves may play in bone metabolism, the morphology of calcitonin gene-related peptide (CGRP)-, vasoactive intestinal peptide (VIP)-, substance P (SP)-, neuropeptide Y (NPY)-, and dopamine-beta-hydroxylase (D beta H)-immunoreactive nerve fibers was examined in whole-mount prepara... |
1906815 | Intranasal estradiol administration to oophorectomized women. | An open, dose-finding study into the effects of a new intranasal 17 beta-estradiol formulation using dimethyl-beta-cyclodextrin as a solubilizer was conducted in nine hysterectomized and oophorectomized patients with symptoms of estrogen deficiency. After nasal delivery of 0.34 mg estradiol in three patients, concentra... |
1648450 | Direct repeats as selective response elements for the thyroid hormone, retinoic acid, and vitamin D3 receptors. | We report here the identification of thyroid hormone response elements (TREs) that consist of a direct repeat, not a palindrome, of the half-sites. Unlike palindromic TREs, direct repeat TREs do not confer a retinoic acid response. The tandem TRE can be converted into a retinoic acid response element by increasing the ... |
1829640 | Characterization of Bacillus stearothermophilus cyclodextrin glucanotransferase in ascorbic acid 2-O-alpha-glucoside formation. | In this study, we characterized cyclodextrin glucanotransferase (CGTase) from Bacillus stearothermophilus in L-ascorbic acid-2-O-alpha-D-glucoside (AA-2G) formation and compared its enzymological properties with those of rat intestinal and rice seed alpha-glucosidases which had the ability to form AA-2G. CGTase formed ... |
2062811 | Use of 2-hydroxypropyl-beta-cyclodextrin as a solubilizing and stabilizing excipient for protein drugs. | A chemically modified, amorphous beta-cyclodextrin, namely, 2-hydroxypropyl-beta-cyclodextrin (HPCD), was examined as a solubilizing and stabilizing agent for protein drugs. The aqueous solubility of ovine growth hormone at pH 7.4 was increased through the use of HPCD. This effect was manifested by higher UV transparen... |
1647980 | Change in charge of an unvaried heme contact residue does not cause a major change of conformation in cytochrome c. | The structure of the Ala38 variant of yeast iso-1-cytochrome c, in which the previously unchanged Arg38 has been replaced, has been characterised by NMR. The NMR data indicate that the structure of the Ala38 variant is very similar to that of the wild type protein. In particular, the heme environment and interactions o... |
1647522 | DNA superhelicity affects the formation of transcription preinitiation complex on eukaryotic genes differently. | In vitro transcription was reconstituted with HeLa cell transcription factors and RNA polymerase II, which were essentially free from DNA topoisomerase activities. DNA templates with defined negative superhelical densities were tested for transcription activity. Transcription of the Bombyx mori fibroin gene increases a... |
1647521 | Anthracycline antibiotic arugomycin binds in both grooves of the DNA helix simultaneously: an NMR and molecular modelling study. | Perturbations to the 1H and 31P chemical shifts of DNA resonances together with twenty-four intermolecular nuclear Overhauser effects show that the anthracycline antibiotic arugomycin intercalates between the basepairs of the hexamer duplex d(5'-GCATGC)2 at the 5'-CpA and 5'-TpG binding sites. In the complex two drug m... |
1829157 | Analysis of the IHF binding site in the regulatory region of bacteriophage Mu. | In bacteriophage Mu the converging early and repressor transcriptions are both stimulated by binding of IHF to the same region, which is located just upstream of the early promoter (Pe) and 100 base pairs downstream of the repressor promoter (Pc). Within this region two sequences are present (ihfa and ihfb) that match ... |
2052622 | Mutation in a gene for type I procollagen (COL1A2) in a woman with postmenopausal osteoporosis: evidence for phenotypic and genotypic overlap with mild osteogenesis imperfecta. | Mutations in the two genes for type I collagen (COL1A1 or COL1A2) cause osteogenesis imperfecta (OI), a heritable disease characterized by moderate to extreme brittleness of bone early in life. Here we show that a 52-year-old postmenopausal woman with severe osteopenia and a compression fracture of a thoracic vertebra ... |
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