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241.
242.
Rauner M Stein N Winzer M Goettsch C Zwerina J Schett G Distler JH Albers J Schulze J Schinke T Bornh?user M Platzbecker U Hofbauer LC 《Journal of bone and mineral research》2012,27(3):575-585
WNT5A has recently been implicated in inflammatory processes, but its role as a bone marrow stromal cell (BMSC)-derived mediator of joint inflammation in arthritis is unclear. Here, we investigated whether inflammatory stimuli induce WNT5A in BMSC to control inflammatory responses. WNT5A levels were determined in human BMSC after stimulation with lipopolysaccharide (LPS) or tumor necrosis factor α (TNF-α,) and in synovial cells and tissue of patients with rheumatoid arthritis (RA) and human TNF-α transgenic (hTNFtg) mice. A microarray analysis of WNT5A-treated murine osteoblasts was performed using Affymetrix gene chips. The regulation of cytokine/chemokine expression was confirmed by qPCR, ELISA, and Luminex technology in BMSC after stimulation with WNT5A or WNT5A knockdown. Relevant signaling pathways were identified using specific inhibitors. Migration of MACS-purified T lymphocytes and monocytes was assessed using the FluoroBlok system. WNT5A expression was increased threefold in BMSC after stimulation with LPS or TNF-α. Synovial fibroblasts from patients with RA showed a twofold increase of WNT5A expression compared with control cells, and its expression was highly induced in the synovial tissue of patients with RA and hTNFtg mice. Microarray analysis of WNT5A-treated osteoblasts identified cytokines and chemokines as targets. The induction of IL-1β, IL-6, CCL2, CCL5, CXCL1, and CXCL5 by WNT5A was confirmed in BMSC and depended on the activation of the NF-κB, mitogen-activated protein (MAPK), and Akt pathways. Accordingly, knockdown of WNT5A markedly reduced the basal and LPS-induced cytokine/chemokine production. Finally, migration of monocytes and T cells toward the supernatant of WNT5A-treated BMSC was increased by 25% and 20%, respectively. This study underlines the critical role of BMSC-derived WNT5A in the regulation of inflammatory processes and suggests its participation in the pathogenesis of RA. 相似文献
243.
Recombinant immunoblot assay reaction patterns and hepatitis C virus RNA in blood donors and non-A, non-B hepatitis patients 总被引:5,自引:0,他引:5
D Bresters ; HL Zaaijer ; HT Cuypers ; HW Reesink ; IN Winkel ; PJ van Exel-Oehlers; AA van Drimmelen; PL Jansen ; CL van der Poel; PN Lelie 《Transfusion》1993,33(8):634-638
To establish the value of the second-generation recombinant immunoblot assay (RIBA-2) and cDNA polymerase chain reaction (cDNA PCR) for confirmation of hepatitis C virus (HCV) infection, anti-HCV reaction patterns and the presence of HCV RNA were examined in 610 blood donors and 255 non-A, non-B hepatitis patients who were positive or indeterminate in RIBA-2. Of RIBA-2-positive donors (n = 191) and patients (n = 224), 75.4 and 89.7 percent, respectively, were HCV RNA positive. The most frequently observed anti-HCV recognition patterns in HCV RNA-positive donors and patients were c22, c33c, and c100 and/or 5- 1-1 (67.3%, 57.7%) and c22, c33c (24.8%, 29.3%). Among subjects with a RIBA-2-indeterminate result, HCV RNA was detected more often in patients (n = 31) than in donors (n = 419): 67.7 and 2.1 percent, respectively. In viremic persons with single-band reactivity in RIBA-2, this reactivity was always directed against either c22 or c33c. HCV RNA was detected by cDNA PCR in none of 162 persons with only anti-c100 and/or anti-5-1-1 reactivity. Therefore, RIBA-2 reactivity against c100 in combination with 5-1-1 should not be considered positive but indeterminate. In RIBA-2-indeterminate persons, HCV RNA detection is necessary for reliable confirmation of HCV infection. 相似文献
244.
Reliability of the third-generation recombinant immunoblot assay for hepatitis C virus 总被引:4,自引:0,他引:4
M Damen ; HL Zaaijer ; HT Cuypers ; H Vrielink ; CL van der Poel; HW Reesink ; PN Lelie 《Transfusion》1995,35(9):745-749
BACKGROUND: In a confirmatory laboratory, the second-generation recombinant immunoblot assay (RIBA-2) was replaced by the third- generation RIBA (RIBA-3) in March 1993. The aim of this validation study was to compare the sensitivity and specificity of RIBA-2 and RIBA- 3 in a routine setting, by using a validated hepatitis C virus (HCV) RNA polymerase chain reaction to establish plasma viremia. STUDY DESIGN AND METHODS: RIBA-2 testing was performed (March 1991-March 1993) in 593 HCV RNA-positive and 1498 HCV RNA-negative subjects. RIBA-3 testing was performed (March 1993-May 1994) in 220 HCV RNA-positive and 530 HCV RNA-negative subjects. All samples reacted for anti-HCV in enzyme- linked immunosorbent assay. RESULTS: In HCV RNA-positive individuals, the sensitivity of RIBA-3 was significantly higher than that of RIBA-2 (99.5% vs. 93.3%, p = 0.0005). This was not caused by inclusion of the NS5 antigen, but by a higher sensitivity of the antigens c33 and c100 (RIBA-2: 94.3% and 62.6%; RIBA-3: 99.5% and 88.6%). Replacement of the c22 and c100 recombinant proteins by synthetic peptides significantly reduced nonspecific reactivity against these antigens (p < 0.0001). Unfortunately, increased nonspecific reactivity against the modified c33 antigen and the new NS5 antigen canceled out this effect. Two-band reactivity occurred more often in nonviremic persons than in viremic persons (32.7% vs. 8.2%, p < 0.0001). Risk factors for HCV infection were less frequently observed in 11 blood donors with two-band reactivity than in 6 blood donors with other positive RIBA-3 patterns (18% vs. 83%, p = 0.03). CONCLUSION: The higher sensitivity of RIBA-3 significantly reduced the number of indeterminate test results in HCV RNA-positive persons. Confirmatory laboratories must be aware of the frequent occurrence of nonspecific, isolated reactivity and even nonspecific, two-band reactivity in anti-HCV enzyme-linked immunosorbent assay-reactive blood donors. 相似文献
245.
中药玉竹有效成分研究 总被引:30,自引:0,他引:30
自江苏海门产百合科植物玉竹[Polygonatum odoratum(Mill.)Druce]根茎的乙醇提取物中分得六个单体化合物,根据化学性质和光谱解析,鉴定其化学结构分别为β-谷甾醇(S-A)),β-谷甾醇-3-O-β-D-吡喃葡萄糖甙(S-B),25(R,S)螺甾-5-烯-3β-醇-3-O-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃木糖基-(1→3)]-β-D-吡喃葡萄糖基(1→4)-β-吡喃半乳糖甙(POD-I),25(R)螺甾-5-烯-3β,14a-二醇-3-0-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃木糖基-(1→3)]-β-D-吡喃葡萄糖基-(1→4)-β-D-吡喃半乳糖甙(POD-II),25(R,S)螺甾-5-烯-3β,14a-二醇-3-O-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃葡萄糖基-(1→3)]-β-D-吡喃葡萄糖基(1→4)-β-D-吡喃半乳糖甙(POD-III)和25(R,S)螺甾-5-烯-3β-醇-3-O-β-D-吡喃葡萄糖基-(1-2)-[β-D-吡喃葡萄糖基-(1→3)]-β-D-吡喃哺葡萄糖基(1→4)-β-D-吡喃半乳糖甙(POD-IV)。POD-II为首次分离得到的25(R)构型的纯品,POD-III和POD-IV为首次从玉竹中得到。经初步药理实验显示,POD-II有诱生集落刺激因子(CSF)的作用,POD-III能协同ConA和Lps对淋巴细胞转化有促进作用。 相似文献