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S Yue

Publications and source records attributed to S Yue.

60 records · Page 4Linked to original sources
PubMed1988

Human S-antigen: characterization of uveitopathogenic sites.

Human S-antigen (HSA) is a 50,000 molecular weight photoreceptor cell protein capable of inducing an experimental autoimmune uveitis (EAU) in susceptible animal strains. In order to determine specific sites responsible for its uveitopathogenicity, we synthesized 39 overlapping peptides corresponding to its entire 404 amino acid sequence and tested each peptide for its ability to induce an EAU in Lewis rats. Two synthetic peptides designated peptide HSA 319 (amino acid positions 286 to 305) and peptide HSA 320 (amino acid positions 306 to 325) were uveitopathogenic when used at 50 and 100 micrograms immunizing doses. Smaller peptides corresponding to the amino, mid, and carboxy terminal portions of each peptide further refined each uveitopathogenic site to 12 amino acids. A computerized analysis of the amino acid sequence of S-antigen indicates that these uveitopathogenic sites are complex and may be related to a two-fold symmetry in the molecule. Our present and previous studies provide a basis for the uveitopathogenicity of human and bovine S-antigen in the pathogenesis of EAU as well as the pathogenesis of certain forms of uveitis in humans.

Amino Acid Sequence↗
PubMed1988

Epitope mapping of bovine retinal S-antigen with monoclonal antibodies.

We examined the binding of seven murine monoclonal antibodies raised to S-antigen, an immunopathogenic, 404 residue photoreceptor cell autoantigen which induces experimental autoimmune uveoretinitis. S-antigen has also been identified as arrestin, a protein involved in the regulation of phototransduction. One additional monoclonal antibody (C10C10), raised to a synthetic peptide (peptide N) corresponding to residues 281 to 302 in bovine S-antigen, was also studied. In preliminary studies we examined the specificity of the antibody response to bovine S-antigen in sera from Balb/c mice. Western blots of mouse sera on the cyanogen bromide digest of bovine S-antigen demonstrated that all animals produced antibody which recognized epitopes within the C-terminal cyanogen bromide peptide designated CB46. Mice of the H-2d haplotype, including the Balb/c strain often used to produce monoclonal antibodies, showed little activity to cyanogen bromide peptides other than CB46. Also, all seven of the monoclonals raised to S-antigen are specific for epitopes in the CB46 peptide. The epitopes recognized by the monoclonal antibodies could be grouped into four distinct sites defined by peptides AE-1 (A2G5), peptide AA (PDS-1), peptide 19-OV (A9C6), and peptide 199 (BDS-1,2,3 and 4). The mono-clonal antibody, C10C10, raised to peptide N recognizes an epitope in the N peptide and binds to a larger cyanogen bromide peptide designated CB123 as well as intact S-antigen. Fine mapping of these epitopes was done with various subpeptides. None of the antibodies bound the known immunopathogenic peptide, peptide M, which resides in CB123 although the C10C10 antibody binds a peptide adjacent to peptide M.

Amino Acid Sequence↗
PubMed1986

Anthracycline metabolites of tetracenomycin C-nonproducing Streptomyces glaucescens mutants.

Mutants of Streptomyces glaucescens GLA.0 which are blocked in the production of tetracenomycin C (compound 1), an anthracycline antibiotic having significant antitumor activity, accumulated several new anthracycline metabolites structurally related to compound 1 and to intermediates of its biosynthetic pathway. Through chemical and spectroscopic comparisons with the known anthracycline metabolites of the wild-type strain, we identified the two regioisomers of tetracenomycin B2 (compounds 7a and 7b), 8-demethyltetracenomycin C (compound 12), tetracenomycin D2 (compound 11), tetracenomycin E (compound 13), and the 12-naphthacenone forms of compounds 7a, 7b, and 2 (tetracenomycin D1). A hypothetical biosynthetic pathway to compound 1 is presented that is consistent with the occurrence of compounds 7b, 13, and 5 (tetracenomycin A2) and with the cosynthetic behavior of tetracenomycin C-nonproducing mutants (H. Motamedi, E. Wendt-Pienkowski, and C. R. Hutchinson, J. Bacteriol. 167:575-580, 1986).

Antibiotics, Antineoplastic↗
PubMedDate not supplied

The fatigue strength of porous-coated Ti-6%Al-4%V implant alloy.

The fatigue behaviour of Ti-6Al-4V (extra low interstital) alloy coated with Ti-6Al-4V powder was investigated using rotating bending fatigue testing. It was found that the high cycle fatigue strength of porous coated specimens exhibited a substantial decrease compared to uncoated specimens of the same microstructure. Chemical analysis of the sintered surface revealed significant increases of interstitials compared to the bulk analysis, but it is concluded that this would not adversely affect the fatigue strength. Scanning electron microscopy revealed crack initiation close to particle/substrate contact interfaces and it is concluded that stress intensification due to these interface regions are major sources of weakness with respect to fatigue strength. Finally it was found that subjecting a polished Ti-6Al-4V specimen to the heat treatment required for sintering resulted in delineation of prior beta grain boundaries and it is suggested that this also contributes to the inferior fatigue strength of porous coated Ti-6Al-4V.

Absorption↗