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91.
妊娠相关糖蛋白Glycodelin抑制E型选择素介导的细胞黏附 总被引:1,自引:0,他引:1
目的探讨来源于孕妇羊水和血清的高纯度Glycodelin对E型选择素介导的细胞黏附过程的影响程度。方法以色谱仪分离和纯化孕妇羊水和血清的Glycodelin,测定铬51标记的肝癌细胞系-HepG2细胞在不同来源、不同浓度Glycodelin作用下和重组E型选择素的黏附能力,从而评价Glycodelin对E型选择素介导的细胞黏附过程的影响。结果血清和羊水Glycodelin能有效抑制Hepg2细胞和重组E型选择素之间的黏附,其抑制作用呈浓度依赖关系,其相对抑制力分别为纯四糖结构Sialyl-Lewisx(sLex)的9.4×105和4.0×105倍。结论妊娠相关糖蛋白Glycodelin高度抑制E型选择素介导的细胞黏附。 相似文献
92.
This study investigated the expression of selectins and chemokines in cultured human lymphatic endothelial cells stimulated with lipopolysaccharides. In microarray, vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 gene expressions in the lymphatic endothelium with lipopolysaccharides did not change at 0.5 h but increased two- to three-fold at 12 h, whereas E-selectin increased 10-fold at 0.5 h and 68-fold at 12 h compared with untreated cells. The E-selectin mRNA and protein increased in the lymphatic endothelial cells with lipopolysaccharides at more than two-fold levels compared with human umbilical vein endothelial cells. Induction of Cys-Cys chemokine ligand 2, 3, 5, 7, 8 and 20 mRNAs in the lymphatic endothelial cells with lipopolysaccharides was detected in microarray and real-time PCR. The Cys-Cys chemokine ligand 2, 5 and 20 mRNA amounts in cells with high concentration lipopolysaccharides were larger in the lymphatic endothelial cells than in human umbilical vein endothelial cells. The Cys-Cys chemokine ligand 3 and 8 mRNAs were not detected in human umbilical vein endothelial cells. Induction of Cys-X-Cys chemokine ligand 1, 3, 5, 6 and 8 mRNAs was detected in the lymphatic endothelial cells with lipopolysaccharides. The Cys-X-Cys chemokine ligand 3, 5 and 8 mRNA amounts in cells with high concentration lipopolysaccharides were larger in the lymphatic endothelial cells than in human umbilical vein endothelial cells. In conclusion, it was demonstrated that the cultured human lymphatic endothelial cells express E-selectin and phagocyte-attractive chemokine genes. 相似文献
93.
目的 探讨参附注射液对行全髋关节置换术的老年患者术中血流动力学和血浆E-选择素浓度的影响.方法 择期行全髋关节置换术老年患者24例,按随机数字表随机分为参附注射液组(S组)与生理盐水对照组(N组),每组12例.术前两组患者一般情况差异无统计学意义.S组:麻醉成功后予参附注射液0.2 ml/kg经外周静脉缓慢注射,继以0.8 ml·kg-1·h-1持续注入至手术结束;N组则以生理盐水替代.术后均予患者自控镇痛(PCEA).检测术前(T0)、手术结束即刻(T3)及术后24 h(T4)血浆E-选择素浓度.分别记录T0、术后15 min(T1)、术后30 min(T2)、T3各时间点心率、平均动脉压和中心静脉压.结果 两组患者手术时间、术中输液差异无统计学意义;两组血流动力学差异均无统计学意义(均P>0.05);S组各时间点血浆E-选择素浓度差异均无统计学意义(均P>0.05),N组在T3、T4时明显升高[(119±23)mg/L、(109±23)mg/L],与T0比较差异有统计学意义[(86±15)mg/L,P<0.01],与S组比较明显高[T0、T3、T4分别为(92±37)、(83±15)、(83±12)mg/L,P<0.05或0.01].结论 行全髋关节置换术的老年患者围术期血浆E-选择素浓度明显升高,参附注射液可以抑制其升高,抑制血管内皮细胞的活化,对血流动力学无明显的影响.Abstract: Objective To investigate the effects of Shenfu (SF) injection on hemodynamics and plasma E-selectin concentrations in elderly patients undergoing total hip replacement (THR). Methods A total of 24 ASA Ⅱ/Ⅲ patients aged 65 to 85 years old were divided equally into two groups (n = 12). In Group S, SF injection was administered by peripheral intravenous infusion at initially 0. 2 ml/kg and then patients received a post-operative regimen of patient-controlled epidural analgesia (PCEA). Blood samples were taken pre-operation ( T0), immediately post-operation (T3) and 24 hours post-operation (T4) so as to detect the levels of E-selectin at these time points.mean arterial pressure (MAP) , heart rate (HR) and central venous pressure (CVP) were continuously monitored and recorded at T0, 15 min post-anesthesia (T1 ), 30 min post-anesthesia (T2) and T3. Results The concentrations of E-selectin in Group N increased at T3 and T4 while those decreased in Group S [(119 ± 23 ) mg/L and(109 ± 23) mg/L vs (86 ±15)mg/L,(83 ±15)mg/L and (83 ±12)mg/L vs(92 ±37)mg/ L, all P<0. 01]. As compared with Group S, they were significantly higher in Group N (P < 0. 05 or 0. 01). There was no significant difference in CVP, HR and MAP between two groups. Conclusion The activation of vascular endothelial cells is manifested by an elevated plasma concentration of E-selectin in the elderly patients undergoing THR. SF injection can inhibit the activation and exert no significant effects on the hemodynamics. 相似文献
94.
目的:探讨E-选择素(E-selectin)基因第2号外显子G98T和第4号外显子A561C多态性及血浆可溶性水平与儿童慢性HBV感染的相关性。方法:采用聚合酶链反应-限制性片段长度多态性分析技术(PCR-RFLP)检测119例慢性HBV感染患儿和141例健康对照者E-选择素基因多态性,同时采用酶联免疫吸附实验(ELISA)检测各组可溶性E-选择素(sE-选择素)水平。结果:血浆sE-选择素水平在慢性HBV感染组与对照组相比差异有统计学意义(P<0.01);E-选择素G98T和A561C多态性中基因型频率和等位基因频率在慢性HBV组与对照组相比差异无统计学意义,各组中C等位基因携带者血浆sE-选择素水平明显高于A等位基因携带者(P<0.05)。结论:E-选择素G98T和A561C基因多态性在慢性HBV感染中不起作用,但A561C基因多态性参与调控血浆可溶性E-选择素的表达。 相似文献
95.
目的探讨长期吸烟对大鼠的肺损伤及相关炎性因子表达的影响。方法 56只雄性SD大鼠,随机分为对照组和低、中、高3个剂量吸烟组,采用自主开发的吸烟机给烟12周;放免法检测支气管肺灌洗液(BALF)中白介素-8(IL-8)的含量,免疫组化法检测肺血管内皮细胞E-选择素的表达水平。结果高、中、低剂量吸烟组大鼠BALF中IL-8的含量分别为(0.77±0.010)、(0.71±0.171)、(0.62±0.088)ng/mL,高于对照组(0.28±0.133))ng/mL,差异有统计学意义(P<0.01);高、中、低剂量吸烟组E-选择素的表达分别为(0.27±0.030)、(0.18±0.034)、(0.16±0.025),均高于对照组(0.07±0.023),差异有统计学意义(P<0.01);中剂量吸烟组肺血管内皮细胞E-选择素与BALF中IL-8的含量呈明显正相关(r=0.716,P<0.01)。结论长期吸烟导致气道炎症介质IL-8和E-选择素的表达升高,促进气道内炎症反应,对支气管肺组织造成严重损害。 相似文献
96.
BackgroundSoy protein in combination with soy isoflavones might reduce the serum concentration of inflammatory mediators. In this study, we attempted to summarize the effect of soy protein combined with soy isoflavones on circulating E-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in adults.MethodsClinicaltrials.gov, Web of Science, Cochrane Library, PubMed, and Scopus were searched for English articles with no time limit regarding publication up to December 2020. Thereafter, the mean changes from baseline and their standard deviations (SDs) for both intervention and comparison groups were used to calculate the effect size. We used DerSimonian and Laird random-effects model if the heterogeneity test was statistically significant. Cochran's Q test and I-squared statistic were also used to calculate the statistical heterogeneity of the intervention effects.ResultsEight articles were found as eligible for this study. The treatment duration was between 6 and 24 weeks. Soy isoflavones dose was in a range of 30–112 mg/day and soy protein dose was in a range of 11.25–52 g/day. Overall, taking soy protein supplements containing soy isoflavones was not associated with changes in cell adhesion molecules, E-selectin, ICAM-1, or VCAM-1 (WMD = 0.65, 95 % CI: -2.58, 3.89; p = 0.692; WMD = 2.68, 95 % CI: -0.98, 6.34; p = 0.151; WMD = 2.66, 95 % CI: -6.28, 11.61; p = 0.559, respectively).ConclusionThe combination of soy protein and soy isoflavones was not significantly associated with changes in levels of E-selectin, ICAM-1, and VCAM-1. However, we need more studies with a large sample size and more participants with different age categories in this regard. 相似文献
97.
98.
Comparative study of adhesion molecule expression in cultured human macro- and microvascular endothelial cells 总被引:8,自引:0,他引:8
Müller AM Hermanns MI Cronen C Kirkpatrick CJ 《Experimental and molecular pathology》2002,73(3):171-180
Culture systems as models for disease are only valid as long as they are comparable to in vivo conditions. The phenotype of cultured endothelial cells (ECs) has only been sporadically compared to the corresponding phenotype in vivo. Thus, we compared by immunolocalization the endothelial expression of ICAM-1, VCAM, and E-selectin in vivo in stimulated/unstimulated human umbilical vein endothelial cells (HUVEC) as a model for macrovascular ECs and stimulated/unstimulated HPMEC (human pulmonary microvessel endothelial cells) as a model for pulmonary microvascular ECs with that in human lungs in vivo (normal and ARDS). Proinflammatory stimuli in vitro were used to stimulate conditions relevant for ARDS. ICAM-1 expression in stimulated HUVEC/HPMEC correlated well with in vivo expression (macro- and microvessels). For E-selectin, the staining pattern in macro/microvessels correlated moderately with unstimulated and well with stimulated HUVEC/HPMEC. For VCAM a good correlation was found for stimulated/unstimulated HUVEC and unstimulated HPMEC. The expression patterns in stimulated HUVEC corresponded well for all three molecules with those in vivo. Thus, the expression patterns in vitro are only partially transferable to in vivo conditions. The study suggests that E-selectin- and VCAM-coated beads could potentially serve in the isolation process of arteriolar and venular ECs. 相似文献
99.
Expression of adhesion molecules was investigated in six biopsy specimens of Langerhans' cell histiocytosis using immunocytochemistry. Cells with Langerhans' cell histiocytosis morphology were stained for ICAM-1, for the beta-1 integrins alpha-4 (VLA-4) and alpha-5 (VLA-5), and for the beta-2 integrins LFA-1, MAC-1 and p150,95. This pattern of reactivity was different from that of epidermal Langerhans' cells of the normal skin which were not immunostained. A variable number of CD68+ multinucleated giant cells was present in five biopsies. They were less reactive than the cells of Langerhans' cell histiocytosis for alpha-4 (VLA-4) and LFA-1, were positive for MAC-1 and p150,95 and were characterized by prominent expression of the beta-1 integrins alpha-2 (VLA-2), alpha-3 (VLA-3) and of VnR (alpha-v/ beta-3). The repertoire of adhesion molecules expressed by giant cells is indicative of profound cell-matrix interactions, whereas that of Langerhans' histiocytosis cells suggests particularly active cell–cell interactions. Blood vessels of the lesions were stained for beta-1 integrins, for vitronectin receptor and for molecules involved in adhesion and trans-endothelial migration of circulating leukocytes, such as ICAM-1, VCAM-1 and E-selectin. Additional findings were the observation of CD1a+ multinucleated giant cells in a single case, suggesting a possible lineage relationship with the histiocytosis cells, and the demonstration of some Ki-67+ Langerhans' cell histiocytosis cells and CD1a+ mitotic figures in four of six cases, indicating local proliferation of Langerhans' histiocytosis cells. 相似文献
100.
A. Sakai 《Inflammation research》1996,45(5):224-229
Stimulation of cultured human umbilical vein endothelial cells (HUVEC) with lipopolysaccharide (LPS) induces adherences for human promyelocytic cell line HL60. Adherence of HL60 cells to HUVEC stimulated with LPS for 4h was completely inhibited by pretreatment with SJC13, an azaindolidine derivative. The mechanism whereby SJC13 inhibits the adhesiveness of HUVEC was investigated. Pretreatment of SJC13 inhibited LPS-induced expression of E-selectin and vascular cell adhesion molecule-1 (VCAM-1), but not intercellular adhesion molecule-1 (ICAM-1), in HUVEC, determined by flow cytometry and cellular enzyme-linked immunosorbent assay (cell-ELISA). The inhibitory activity was concentration dependent between 62.5 and 1,000 g/ml. SJC13 also selectively inhibited LPS-induced increases in E-selectin and VACM-1 mRNAs, indicating that the action of SJC13 is to inhibit synthesis of these molecules. These data demonstrate that SJC13 is capable of selectively inhibiting the expression of E-selectin and VCAM-1, but not ICAM-1, in endothelial cells.accepted by I. Ahnfelt-Rønne 相似文献