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Catherine Ronin Herman van Halbeek Johannah GM Mutsaers Johannes F G Vliegenthart 《Glycoconjugate journal》1987,4(3):247-254
The lipid-linked precursor ofN-type glycoprotein oligosaccharides was isolated from porcine thyroid microsomes after in cubation with UDP[3H] Glucose. The carbohydrate was released from dolichol pyrophosphate by mild acid hydrolysis, purified by gel filtration and characterized by 500-MHz1H-NMR spectroscopy in combination with enzymatic degradation. The parent oligosaccharide was found to be Glc3Man9Glc-NAc2. The three glucose residues are present in the linear sequence Glcα1-2Glα1-3 Glc, the latter being α(1-3)-linked to one of the mannose residues. In order to establish the branch location of the triglucosyl unit, the parent compound was digested with jack-bean α-mannosidase. The oligosaccharide product was purified by gel filtration, and identified by1H-NMR as Glc3Man5GlcNAc2 lacking the mannose residues A, D2, B and D3. Therefore, the structure of the precursor oligosaccharide is as follows: $$\begin{gathered} c b a D_1 C 4 \hfill \\ Glc\alpha 1 - 2Glc\alpha 1 - 3Glc\alpha 1 - 3Man\alpha 1 - 2Man\alpha 1 - 2Man\alpha 1 \hfill \\ 3 \swarrow 3 2 1 \hfill \\ Man\alpha 1 - 2Man\alpha 1 Man\beta 1 - 4GlcNAc\beta 1 - 4GlcNAc \hfill \\ D_{2 } A 3 6 \hfill \\ Man\alpha 1 \hfill \\ 6 \hfill \\ Man\alpha 1 - 2Man\alpha 1 \nwarrow 4 \hfill \\ D_3 B \hfill \\ \end{gathered} $$ 相似文献
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G M Dallinga-Thie A van Tol F M van't Hooft P H Groot 《Biochimica et biophysica acta》1986,876(1):108-115
The distribution of apolipoproteins A-I and A-IV among lymph lipoprotein fractions was studied after separation by molecular sieve chromatography, avoiding any ultracentrifugation. Lymph was obtained from rats infused either with a glucose solution or with a triacylglycerol emulsion. Relative to glucose infusion, triacylglycerol infusion caused a 20-fold increase in the output of triacylglycerol, coupled with a 4-fold increase in output of apolipoprotein A-IV. The output of apolipoprotein A-I was only elevated 2-fold. Chromatography on 6% agarose showed that lymph apolipoproteins A-I and A-IV are present on triacylglycerol-rich particles and on particles of the size of HDL. In addition, apolipoprotein A-IV is also present as 'free' apolipoprotein A-IV. The increase in apolipoprotein A-I output is caused by a higher output of A-I associated with large chylomicrons only, while the increase in apolipoprotein A-IV output is reflected by an increased output in all lymph lipoprotein fractions, including lymph HDL and 'free' apolipoprotein A-IV. The increased level of 'free' A-IV, seen in fatty lymph, may contribute to, and at least partly explain, the high concentrations of 'free' apolipoprotein A-IV present in serum obtained from fed animals. 相似文献
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New genetic variants in the apoA-I and apoC-III genes and familial combined hyperlipidemia 总被引:3,自引:0,他引:3
Linkage and association between the apolipoprotein (apo) A-I/C-III/A-IV gene region on chromosome 11 and familial combined hyperlipidemia (FCHL) has been observed previously. Using sequence analysis two new allelic variants were identified, C(317) -T in intron 2 of the apoA-I gene and C(1100)-T in exon 3 of the apoC-III gene. These variants were studied in 30 FCHL probands, 159 hyperlipidemic relatives, 327 normolipidemic relatives, and 218 spouses. The allele frequencies of both variants were significantly different in probands and spouses (P < 0.002 and P < 0.001, respectively), with increased frequency of the minor alleles in the probands. The minor genotypes (TT) were associated with elevated plasma triglyceride and apoC-III. Both variants were in strong, although not complete, linkage disequilibrium with each other and with the MspI site in the promoter region of the apoA-I gene and the SstI site in the 3' untranslated region of exon 4 of the apoC-III gene. Haplotypes based on these four variants were constructed and the distributions of haplotype combinations were significantly different (P < 0.0001). Two distinct haplotypes predisposing to FCHL were found: 2-2-1-2 and 1-2-2-2 (MspI, C(317) -T; SstI, C(1100)-T). The haplotype combinations carrying one of these high risk alleles are associated with elevated lipid levels in probands and in spouses. While these effects can be attributed to the presence of the M2 and S2 minor alleles, these results suggest that the importance of specific allelic haplotypes may be greater than single genotypic effects. 相似文献
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Sebastian Dolff Daniel Quandt Benjamin Wilde Thorsten Feldkamp Fan Hua Xin Cai Christof Specker Andreas Kribben Cees GM Kallenberg Oliver Witzke 《Arthritis research & therapy》2010,12(4):R150
Introduction
There is growing evidence that interleukin 17 (IL-17) producing T cells are involved in the pathogenesis of systemic lupus erythematosus (SLE). Previous studies showed that increased percentages of T-cell subsets expressing the costimulatory molecules CD80 and CD134 are associated with disease activity and renal involvement in SLE. The aim of this study was to investigate the distribution and phenotypical characteristics of IL-17 producing T-cells in SLE, in particular in patients with lupus nephritis, with emphasis on the expression of CD80 and CD134. 相似文献7.
van der Steeg WA Hovingh GK Klerkx AH Hutten BA Nootenboom IC Levels JH van Tol A Dallinga-Thie GM Zwinderman AH Kastelein JJ Kuivenhoven JA 《Journal of lipid research》2007,48(3):674-682
It is unclear whether cholesteryl ester transfer protein (CETP) contributes to high density lipoprotein cholesterol (HDL-C) levels in hyperalphalipoproteinemia (HALP) in Caucasians. Moreover, even less is known about the effects of hereditary CETP deficiency in non-Japanese. We studied 95 unrelated Caucasian individuals with HALP. No correlations between CETP concentration or activity and HDL-C were identified. Screening for CETP gene defects led to the identification of heterozygosity for a novel splice site mutation in one individual. Twenty-five heterozygotes for this mutation showed reduced CETP concentration (-40%) and activity (-50%) and a 35% increase of HDL-C compared with family controls. The heterozygotes presented with an isolated high HDL-C, whereas the remaining subjects exhibited a typical high HDL-C/low-triglyceride phenotype. The increase of HDL-C in the CETP-deficient heterozygotes was primarily attributable to increased high density lipoprotein containing apolipoprotein A-I and A-II (LpAI:AII) levels, contrasting with an increase in both high density lipoprotein containing apolipoprotein A-I only and LpAI:AII in the other group. This study suggests the absence of a relationship between CETP and HDL-C levels in Caucasians with HALP. The data furthermore indicate that genetic CETP deficiency is rare among Caucasians and that this disorder presents with a phenotype that is different from that of subjects with HALP who have no mutation in the CETP gene. 相似文献
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Arends S Brouwer E van der Veer E Groen H Leijsma MK Houtman PM Th A Jansen TL Kallenberg CG Spoorenberg A 《Arthritis research & therapy》2011,13(3):R94
Introduction
Identifying ankylosing spondylitis (AS) patients who are likely to benefit from tumor necrosis factor-alpha (TNF-α) blocking therapy is important, especially in view of the costs and potential side effects of these agents. Recently, the AS Disease Activity Score (ASDAS) has been developed to assess both subjective and objective aspects of AS disease activity. However, data about the predictive value of the ASDAS with respect to clinical response to TNF-α blocking therapy are lacking. The aim of the present study was to identify baseline predictors of response and discontinuation of TNF-α blocking therapy in AS patients in daily clinical practice. 相似文献10.
de Groot L Hinkema H Westra J Smit AJ Kallenberg CG Bijl M Posthumus MD 《Arthritis research & therapy》2011,13(6):R205