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1.
Julia I. Gavrilyuk Ulrich Wuellner Syed Salahuddin Rajib K. Goswami Subhash C. Sinha Carlos F. Barbas 《Bioorganic & medicinal chemistry letters》2009,19(14):3716-3720
Irreversible chemical programming of monoclonal aldolase antibody (mAb) 38C2 has been accomplished with β-lactam equipped mono- and bifunctional targeting modules, including a cyclic-RGD peptide linked to either the peptide (d-Lys6)-LHRH or another cyclic RGD unit and a small-molecule integrin inhibitor SCS-873 conjugated to (d-Lys6)LHRH. We also prepared monofunctional targeting modules containing either cyclic RGD or (d-Lys6)-LHRH peptides. Binding of the chemically programmed antibodies to integrin receptors α(v)β(3) and α(v)β(5) and to the luteinizing hormone releasing hormone receptor were evaluated. The bifunctional and bivalent c-RGD/LHRH and SCS-783/LHRH, the monofunctional and tetravalent c-RGD/c-RGD, and the monofunctional bivalent c-RGD chemically programmed antibodies bound specifically to the isolated integrin receptor proteins as well as to integrins expressed on human melanoma M-21 cells. c-RGD/LHRH, SCS-783/LHRH, and LHRH chemically programmed antibodies bound specifically to the LHRH receptors expressed on human ovarian cancer cells. This approach provides an efficient, versatile, and economically viable route to high-valency therapeutic antibodies that target defined combinations of specific receptors. Additionally, this approach should be applicable to chemically programmed vaccines. 相似文献
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The biosynthesis of glyantrypine from radiolabelled amino acid precursors has been shown experimentally to involve anthranilic acid, tryptophan and glycine. Low values for percentage incorporation of radiolabel into glyantrypine were partly influenced by a complex array of other novel alkaloids shown by the radiolabelling experiments to be related to glyantrypine. Interpretation of radiolabel incorporation from [14C-carboxyl]-anthranilic acid into microbial metabolites seen to contain an anthranilyl moiety in various biosynthetic arrangements is discussed. The possibility of diversion of anthranilic acid from the kynurenine pathway to glyantrypine biosynthesis is recognised. 相似文献
4.
Specific and nonspecific T-cell invasion into cerebrospinal fluid has been investigated in the nonfatal viral meningoencephalitis induced by intracerebral inoculation of mice with vaccinia virus. At the peak of the inflammatory process on Day 7 approximately 5 to 10% of the Lyt 2+ T cells present are apparently specific for vaccinia virus. Concurrently, in mice primed previously with influenza virus, 0.5 to 1.0% of the appropriate T-cell set located in cerebrospinal fluid is reactive to influenza-infected target cells. This vaccinia virus-induced inflammatory exudate may thus contain as many as 500 influenza-immune memory T cells. These findings are discussed from the aspect that such nonspecific T-cell invasion into the central nervous system during aseptic viral meningitis could result in exposure of potentially brain-reactive T cells to central nervous system components. 相似文献
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The enzymic estimation of glutamate and glutamine 总被引:2,自引:1,他引:1
A method of estimating glutamic acid is described, based on its dehydrogenation by glutamate dehydrogenase coupled, by means of N-methylphenazine methosulphate, to the reduction of tetrazolium salts. The method is suitable for the estimation of 0-0.3mumole of glutamic acid. The response is linear, but not stoicheiometric: possible reasons for this are discussed. If suitable precautions are taken, the use of a partially purified preparation of glutaminase makes it possible to estimate glutamine also. 相似文献
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The Saccharomyces Cerevisiae Ku Autoantigen Homologue Affects Radiosensitivity Only in the Absence of Homologous Recombination 总被引:14,自引:0,他引:14
In mammalian cells, all subunits of the DNA-dependent protein kinase (DNA-PK) have been implicated in the repair of DNA double-strand breaks and in V(D)J recombination. In the yeast Saccharomyces cerevisiae, we have examined the phenotype conferred by a deletion of HDF1, the putative homologue of the 70-kD subunit of the DNA-end binding Ku complex of DNA-PK. The yeast gene does not play a role in radiation-induced cell cycle checkpoint arrest in G(1) and G(2) or in hydroxyurea-induced checkpoint arrest in S. In cells competent for homologous recombination, we could not detect any sensitivity to ionizing radiation or to methyl methanesulfonate (MMS) conferred by a hdf1 deletion and indeed, the repair of DNA double-strand breaks was not impaired. However, if homologous recombination was disabled (rad52 mutant background), inactivation of HDF1 results in additional sensitization toward ionizing radiation and MMS. These results give further support to the notion that, in contrast to higher eukaryotic cells, homologous recombination is the favored pathway of double-strand break repair in yeast whereas other competing mechanisms such as the suggested pathway of DNA-PK-dependent direct break rejoining are only of minor importance. 相似文献
8.
The Saccharomyces cerevisiae MEC1 gene, which encodes a homolog of the human ATM gene product, is required for G1 arrest following radiation treatment. 总被引:2,自引:0,他引:2 下载免费PDF全文
The Saccharomyces cerevisiae gene MEC1 represents a structural homolog of the human gene ATM mutated in ataxia telangiectasia patients. Like human ataxia telangiectasia cell lines, mec1 mutants are defective in G2 and S-phase cell cycle checkpoints in response to radiation treatment. Here we show an additional defect in G1 arrest following treatment with UV light or gamma rays and map a defective arrest stage at or upstream of START in the yeast cell cycle. 相似文献
9.
Research Notes on Avian Biology 1994: Selected Contributions from the 21st International Ornithological CongressMorphology and Physiology: Orientation
Subject: Navigation and orientation 相似文献10.
The HLA class II sequences included in this compilation are taken from publications listed in the papers: Nomenclature for factors of the HLA system, 1989, Nomenclature for factors of the HLA system, 1990, and Nomenclature for factors of the HLA system, 1991 (WHO Nomenclature Committee 1990, 1991, 1992). Where discrepancies have arisen between reported sequences, the original authors have been contacted where possible, and necessary amendments to published sequences have been incorporated into this alignment. Future sequencing may identify errors in this list, and we would welcome any evidence that helps to maintain the accuracy of this compilation. In the sequence alignments, identity between residues is indicated by a hyphen (-), an unavailable sequence is indicated by an asterisk (*), and gaps in the sequence are inserted to maintain the alignment between different alleles showing variation in amino acid number.
Correspondence to: S. G. E. Marsh. 相似文献