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91.
支气管哮喘患者粘附分子和细胞因子的变化及其意义 总被引:2,自引:0,他引:2
目的:探讨支气管哮喘患者外周血白细胞粘附分子β2整合素(β2-integrin熏CD18)、血清可溶性细胞间粘附分子-1(sICAM-1,CD54)、白细胞介素-6(IL-6)和白细胞介素-8(IL-8)的变化及其意义。方法:采用流式细胞仪技术检测外周血白细胞CD18和血清sICAM-1的表达;采用酶连接免疫吸附方法(ELISA)检测血清IL-6和IL-8水平。结果:(1)与正常对照组相比,支气管哮喘患者外周血白细胞CD18和血清sICAM-1表达显著增加穴P<0.05雪;(2)与正常对照组相比,支气管哮喘患者血清IL-6和IL-8水平显著增加穴P<0.05雪;(3)支气管哮喘患者外周血白细胞CD18和血清sICAM-1表达呈显著正相关(r=0.791熏P<0.05)。结论:支气管哮喘患者外周血白细胞CD18和血清sICAM-1表达以及IL-6和IL-8水平增加,可能是支气管哮喘重要的发病机制之一。 相似文献
92.
人白细胞介素18(hIL-18)的纯化及生物学活性的鉴定 总被引:1,自引:1,他引:1
目的:在大肠杆菌中高效表达重组人IL-18(rhIL-18)蛋白,制备具有高纯度、高活性的rhIL-18。方法:用IFTG诱导重组蛋白表达载体pKK223-3/hIL-18进行蛋白表达;菌体经超声破碎分离包含体,并对包含体进行洗涤、变性和复性处理,用DEAE-Sepharose CL-6B阴离子交换柱纯化复性的rhIL-18;以人外周血单核淋巴细胞,通过T细胞增殖实验、^125I-UdR标记的细胞毒实验、ELISA方法检测细胞因子的产生量等方法,测定rhIL-18的生物学活性。结果:在大肠杆菌中成功地诱导、表达了rhIL-18,SDS-PAGE凝胶电泳分离显示在分子量大约18.3kD处有一诱导蛋白带,Western blot证明表达产物与抗IL-18单克隆抗体有特异性免疫反应;表达产物经纯化后纯度达94%;表达的rhIL-18蛋白具有促进T细胞增殖、增强NK细胞细胞毒作用及诱导外周血单核淋巴细胞合成IFN-γ的能力,基本上具有天然IL-18相同的生物学活性。结论:为rhIL-18的获得及为进一步研究其生物学功能提供了一定的条件,并为将rhIL-18用于肿瘤的免疫生物治疗奠定了基础。 相似文献
93.
Zahariev A Bergouignan A Caloin M Normand S Gauquelin-Koch G Gharib C Blanc S 《European journal of applied physiology》2005,95(4):344-350
Because body composition is altered during head-down bed rest (HDBR), body mass can not be used as an index of energy balance.
Consequently diet allowances should not be based on body mass evolution but on fat mass changes. Though criticized, skinfold
thickness (ST) is the costless, easiest and fastest method to use for such an objective. The aim of this study was to compare
the percentage of body fat (%BF) estimated by ST with the isotope dilution of H218O. We compiled data from three HDBR campaigns, one on women (n=8) in November 1998 and two on the same men (n=8) in December 1997 (without countermeasure) and January 1998 (with thigh-cuffs countermeasure), according to a crossover
design. Body composition was assessed before and after 6 days of HDBR. %BF was derived from the biceps, triceps, sub-scapular
and sup-iliac ST according to Durnin and Wormersly (1974). Fat-free mass was measured on the same day by H218O dilution and fat mass was calculated by the difference with body mass and expressed as a percentage. Based on precision
tests, the minimum measurable change by ST was 1.1%BF for single measurement point. Both intercepts (F
4,30=0.89, P=0.45) and slopes (F
4,30=0.74; P=0.57) of the ST versus dilution relationships were not affected by the periods (December vs January), experimental conditions
(control vs HDBR vs HDBR + thigh cuffs) or sex allowing the derivation of a common relationship %BFst=0.94 × %BFdil (F
1,47=97.9, P<0.0001; non-significant intercept excluded) with a bias between methods of −1.7±2.0 %BF (95% CI: −5.8, 2.4 %BF). ST can be
used to measure %BF during HDBR provided great care is placed on training and changes are higher than 1.1 %BF. If the method
can be applied for in-flight energy balance monitoring given the high observed energy deficit, a tight monitoring of the individual
nutritional status as needed during simulation appears, however, dubious based on this solely method. 相似文献
94.
目的应用rhIL-18在体外培养系统(Coculture system in vitro,CCs)中诱导肿瘤特异性细胞毒性T淋巴细胞(Cytotoxic T Lymphocyte,CTL),探讨IFN-γ在rhIL-18诱导的肿瘤特异性CTL产生过程及杀伤效应中的作用.方法采用Stem SepTM免疫磁性细胞分离法分离人外周血NK细胞、T细胞及DCs细胞,流式细胞仪分析细胞表型,125Ⅰ-UdR标记的细胞毒实验检测杀伤活性,ELISA方法检测IFN-γ蛋白产生量,RT-PCR检测IFN-γ mRNA表达含量.结果在肿瘤抗原存在的条件下,IL-18在CCs中能够诱导并促进CTL介导的肿瘤特异性杀伤效应;IL-18能够在肿瘤抗原刺激的CCs中诱导IFN-γ mRNA的表达及IFN-γ蛋白的产生,并与IL-18的含量呈剂量依赖关系,在rhIL-18含量为100 ng时,培养上清中IFN-γ为4 410±210 pg/ml.但加入抗IFN-γ抗体对rhIL-18诱导的肿瘤特异性CTL产生过程无明显影响,不能抑制IL-18诱导的这种肿瘤特异性CTL的杀伤效应.结论IL-18能够在肿瘤抗原刺激的CCs中有效地诱导CTL介导的肿瘤特异性杀伤效应,并诱导IFN-γ的产生,但其诱导肿瘤特异性CTL的产生过程及杀伤效应与IFN-γ无关. 相似文献
95.
Elisabet Costa Silvia Canudas Ivan Garcia-Bassets Silvia Pérez Irene Fernández Ernest Giralt Fernando Azorín M. Lluïsa Espinás 《Chromosome research》2006,14(5):515-526
SAP18 is a highly conserved protein that was proposed to be involved in multiple cellular processes from autophagy to gene
regulation and mRNA processing. In this paper we show that, in Drosophila, dSAP18 is a predominantly nuclear protein that associates to both chromosomes and the nuclear matrix. dSAP18 becomes nuclear
early during development, at the onset of cellularization, and remains so all through embryo development. dSAP18 is also nuclear
in salivary glands, ovaries and cultured S2 cells. Here we also show that dSAP18 forms a complex with the Drosophila homolog of pinin (dPnn), a protein factor involved in mRNA splicing. dSAP18-dPnn interaction was confirmed in vivo, through co-immunoprecipitation experiments, as well as in vitro, through GST pull-down assays. These results are discussed in the context of the possible functions played by SAP18. 相似文献
96.
Kalinski T Krueger S Pelz AF Wieacker P Hartig R Röpke M Schneider-Stock R Dombrowski F Roessner A 《Virchows Archiv : an international journal of pathology》2005,446(3):287-299
The permanent human cell line C3842 was established from a secondary chondrosarcoma in a typical case of Olliers disease. In the present study, we analyzed the morphological, cytogenetic and molecular biological characteristics of the cultured cells in comparison with the original tumor and investigated the invasion properties of the tumor model using functional imaging of proteolysis, matrigel assay and chick chorioallantoic membrane assay. C3842 cells exhibit the typical features of malignant cartilage tumor cells in vitro, including the expression of collagen types II, IX, XI and aggrecan. The proteolytic ability of C3842 cells is attributed to the expression of several proteases, such as cathepsin B, urokinase plasminogen activator and matrix-metalloproteinase-2, which enable the cells to degrade collagen type I and to permeate matrigel matrix. In accordance with the biological features in vivo, C3842 cells are not able to invade through the epithelium of the chick chorioallantoic membrane. In conclusion, the cell line C3842 provides the first model of a secondary chondrosarcoma in Olliers disease in vitro, which is characterized by distinct features of such malignant cartilage tumors. 相似文献
97.
Adenoviruses 12 and 31, but not Ad18, agglutinate rat blood cells at high titer, providing suitable blood cells be available and a prolonged contact period of virus with the erythrocytes is allowed. Purified virus particles show direct, and virus-free supernatants show direct and indirect, hemagglutination, ie, enhancement of HA by heterologous antiserum. Hemagglutination inhibition with rabbit antisera shows cross-reactions between Ad12 and Ad31 with titers 4--32 times lower than with homologous antigens; Ad18 antisera react with antigens from both of the other serotypes. No cross-reactions were seen with antisera from other adenoviruses. This suggests an antigenic relationship of the three viruses of subgroup IV in their fiber antigen gamma, in addition to the known relation in the hexon (epsilon), which is apparent in cross-neutralization. 相似文献
98.
Falk W. Lohoff Marion Lautenschlager Johannes Mohr Thomas N. Ferraro Thomas Sander Jürgen Gallinat 《Neuroscience letters》2008
Vesicular monoamine transporters are involved in the presynaptic packaging of norepinephrine, dopamine and serotonin into storage vesicles. The vesicles release their content upon arrival of an action potential into the synaptic cleft. Dysregulation of monoaminergic neurotransmission has been long postulated to play a relevant role in the etiology of neuropsychiatric disorders. The gene encoding the vesicular monoamine transporter 1 (VMAT1/SLC18A1) maps to chromosome 8p21, a region where several linkage peaks overlap between schizophrenia, bipolar disorder and anxiety-related personality traits. In this study, we tested the hypothesis that the missence variation Thr136Ile in the VMAT1/SLC18A1 gene is associated with anxiety-related personality traits. We tested a total of 337 unrelated subjects of German descent (167 male, 170 female). All participants were carefully screened for psychiatric disorders. The self-report State–Trait Anxiety Inventory (STAI) was completed by all subjects. Genotypes were obtained for the Thr136Ile (rs1390938) variation in the VMAT1 gene for all subjects. Genotype effects on personality variables were computed with MANOVA including age as a co-variant and gender as independent factor (MANCOVA). Results show that STAI scores were significantly affected by genotype (F = 3.108; d.f. = 4,331; p = 0.015) and age (F = 7.233; d.f. = 2,331; p = 0.001) but not by gender. A gender-by-genotype effect was observed for both the STAI state (p = 0.052) and trait score (p = 0.035). Dissection of the group by gender and subsequent contrast analysis of the genotype effects performed within the female group showed significant results (STAI state: Thr/Ile vs. Ile/Ile: T = 4.408, p = 0.0004; STAI trait: Thr/Ile vs. Ile/Ile: T = 3.074, p = 0.009) but not in the male group. Our findings support the hypothesis that anxiety-related personality traits are associated with variation in the VMAT1/SLC18A1 gene. 相似文献
99.
Involvement of interleukin 18 in Crohn's disease: evidence from in vitro analysis of human gut inflammatory cells and from experimental colitis models 总被引:8,自引:0,他引:8 下载免费PDF全文
Maerten P Shen C Colpaert S Liu Z Bullens DA van Assche G Penninckx F Geboes K Vanham G Rutgeerts P Ceuppens JL 《Clinical and experimental immunology》2004,135(2):310-317
An imbalance of immunoregulatory factors and/or cells contributes to uncontrolled mucosal T cell activation and inflammation in Crohn's disease (CD). Bioactive interleukin (IL)-18 has been shown to be produced by macrophages in CD lesions. We report here that T cells freshly isolated from inflamed tissue of CD patients (and not T cells from control intestinal tissue) were responsive to IL-18. In the presence of IL-18, these T cells produced more interferon (IFN)-gamma and less IL-10. To analyse further the role of IL-18 in this disease, an acute and a chronic model of murine colitis were used. IL-18 mRNA was significantly enhanced in trinitrobenzene sulphonic acid (TNBS) induced colitis, and treatment with IL-18 binding protein (IL-18BPa), which neutralizes IL-18 bioactivity, significantly reduced the severity of colitis. However, IL-18BPa did not affect the course of chronic colitis in CD45RBhighCD4+ T cell reconstituted SCID mice. Production of IFN-gamma in lamina propria mononuclear cell cultures from IL-18BPa-treated SCID mice was decreased, but at the same time fewer lamina propria CD4+ T cells harvested from IL-18BPa-treated mice compared to non-treated mice were in apoptosis. We conclude that IL-18 clearly has a modulatory role in the inflammatory cascade of CD and experimental colitis by affecting IFN-gamma and IL-10 production, and apoptosis. In view of the divergent effects of IL-18 neutralization in the two different murine colitis models, it is unlikely that IL-18 is at the top of this cascade. 相似文献
100.
慢性肾衰患者外周血IL-18水平及血液透析对其的影响 总被引:6,自引:0,他引:6
为探讨慢性肾衰竭 (CRF )患者外周血IL 18表达量的变化以及血液透析 (HD )对其表达的影响 ,选取 10名健康志愿者及 2 9例CRF患者 ,应用ELISA测定血浆IL 18水平 ,同时采用半定量逆转录多聚酶链反应 (RT PCR )技术 ,检测PBMC中IL 18mRNA表达量。结果是未行HD的CRF患者血浆IL 18水平及PBMCIL 18mRNA表达量较正常对照组增高 ,差异有显著统计学意义 (P <0 0 1) ,单次HD对CRF患者血浆IL 18水平及基因表达无明显影响 (P >0 0 5 ) ,但长期维持HD则可使CRF患者外周血IL 18水平及基因表达增高 (P <0 0 5 )。提示外周血IL 18的高表达可能参与CRF的发病过程及HD相关并发症的发生发展 相似文献