The heterogeneity of the glycosylation of alpha-1-acid glycoprotein between the sera and synovial fluid in rheumatoid arthritis

Alpha-1-acid glycoprotein (AGP) is a plasma glycoprotein produced by the liver that undergoes increased production and altered glycosylation in several physiological and pathological conditions including rheumatoid arthritis. To date, although present in the synovial fluid of rheumatoid arthritis patients, there has been no evidence for the separate extra-hepatic production of AGP. This study indicates that there could be a localized production of AGP in rheumatoid synovial fluid by demonstrating that the glycosylation patterns of AGP differed between the serum and synovial fluid in the same rheumatoid patient. Serum AGP was largely composed of fucosylated tri- and tetra-antennary oligosaccharide chains while the synovial fluid contained mainly bi-antennary chains that were fucosylated to a lesser extent. This structural heterogeneity of glycosylation resulted in functional diversity; serum but not synovial AGP is able to inhibit binding to the cell adhesion molecule E-selectin through expression of antigen sialyl Lewis X.     

Two-dimensional electrophoresis of cereal prolamins: applications to biochemical and genetic analyses

Three complementary two-dimensional systems for the analysis of cereal prolamins are described. These are electrophoresis at pH 3.1 followed by electrophoresis at pH 9.2, isoelectric focusing (IEF) followed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and SDS-PAGE under non-reducing conditions followed by SDS-PAGE with reduction. They together give information on the pIs, Mrs and charge properties of the individual prolamin components, and on their interactions to form oligomers stabilized by inter-chain disulphide bonds. The three systems are then compared for their effectiveness in analysing unreduced prolamin I fractions from wheat and rye, and the IEF/SDS-PAGE system for analysing reduced and pyridylethylated prolamin fractions from all the major cereals. Finally, applications of the systems in biochemical and genetic studies are discussed and illustrated with three examples: analysis of the structural relationships of the S-rich prolamins (B hordeins and gamma-type hordeins) of barley, determination of the interactions of wheat and rye prolamin subunits in a 2RS/2BL translocation line, and the mapping of genes for alpha-type prolamins in the wild grass Haynaldia villosa.     

Efficient synthesis of methyl lycotetraoside, the tetrasaccharide constituent of the tomato defence glycoalkaloid alpha-tomatine

Branched oligosaccharide lycotetraose, beta-D-glucopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranose, is a key constituent of many steroidal saponins, including glycoalkaloid alpha-tomatine, which is involved in protection of plants from invading pathogens. A new synthesis of the methyl beta-lycotetraoside () is described. Key steps of the synthesis include two successive glycosylation reactions of disaccharide acceptor methyl (4,6-O-benzylidene-3-O-p-methoxybenzyl-beta-D-glucopyranosyl)-(1-->4)-2,3,6-tri-O-benzyl-beta-D-galactopyranoside with readily available benzoylated trichloroacetimidates of alpha-D-glucopyranose and alpha,beta-D-xylopyranose. This scheme allows sequential glycosylation in one-pot on account of the convenient in situ removal of a p-methoxybenzyl protecting group under the acid conditions of the first glycosylation step. Following deprotection, tetrasaccharide was obtained in 19% yield over eight steps.     

Continuous wave dye laser excitation spectroscopy CaF A2Πr-X2Σ+

Excitation spectra for the CaF A²Π-X²Σ(0, 0), (1, 1), and (1, 0) bands have been observed and assigned. The rotational analysis of the CaF A-X and B-X bands by B. S. Mohanty and K. N. Upadhya [Ind. J. Pure Appl. Phys.5, 523 (1967)] is shown to be incorrect. Because it is possible to make independent rotational assignments of each line in an excitation spectrum by observing frequency differences and relative intensities in photoluminescence spectra, tunable laser excitation spectroscopy promises less ambiguity than traditional techniques for assignment of dense, badly overlapped spectra.The following spectroscopic constants (in cm^?1) are obtained for the CaF A²Π and X²Σ states. Numbers in parentheses correspond to three standard deviations uncertainty in the last digit.

     

120.

Searches for new quarks and leptons produced in Z-boson decay     

Abrams GS  Adolphsen CE  Averill D  Ballam J  Barish BC  Barklow T  Barnett BA  Bartelt J  Bethke S  Blockus D  Bonvicini G  Boyarski A  Brabson B  Breakstone A  Bulos F  Burchat PR  Burke DL  Cence RJ  Chapman J  Chmeissani M  Cords D  Coupal DP  Dauncey P  DeStaebler HC  Dorfan DE  Dorfan JM  Drewer DC  Elia R  Feldman GJ  Fernandes D  Field RC  Ford WT  Fordham C  Frey R  Fujino D  Gan KK  Gero E  Gidal G  Glanzman T  Goldhaber G  Gomez Cadenas JJ  Gratta G  Grindhammer G  Grosse-Wiesmann P  Hanson G  Harr R  Harral B  Harris FA 《Physical review letters》1989,63(22):2447-2451

     

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	$\text{X}{}^2\text{Σ}$		$\text{A}{}^2\text{Π}$
$\text{ν}{}_{00}$	0	${}^2\text{Π}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$	16493.1(6)
		${}^2\text{Π}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$	16565.6(6)
$\text{Δ}\text{G(}\text{1}\text{2}\text{)}$	581.1(9)	${}^2\text{Π}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$	586.8(9)
$\text{B}{}_{\mathrm{e}}$	0.3385(11)		0.3436(12)
$\text{B}{}_{\mathrm{e}}\text{(}\text{Ω}\text{=}\text{3}\text{2}\text{) ? B}{}_3\text{(}\text{Ω}\text{=}\text{1}\text{2}\text{)}$	—		0.00312(21)
α	0.00255(48)		0.00283(45)
$\text{D(}\text{estimated}\text{)}$	4.44 × 10?7		4.55 × 10?7
γ(spin-spin)	|γ| < 3 × 10?3		—
$\text{A}{}_0\text{(}\text{spin-orbit}\text{)}$	—		73.4(9)
$\text{p(}\text{lambda doubling}\text{)}$	—		?0.045(4)