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81.
Increased spontaneous secretion of rheumatoid factor by intestinal lamina propria mononuclear cells from Crohn's disease but not ulcerative colitis patients. 总被引:1,自引:0,他引:1
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R P MacDermott S Schreiber G S Nash W J Koopman 《Clinical and experimental immunology》1993,92(1):152-157
Increased levels of rheumatoid factors (RF) have been observed in the serum of Crohn's disease but not ulcerative colitis patients, and have been proposed to relate to an increased state of intestinal lymphocyte activation. We have therefore examined the spontaneous in vitro secretion of RF by intestinal lamina propria mononuclear cells (MNC) isolated from specimens from control and inflammatory bowel disease (Crohn's disease, ulcerative colitis) patients. Normal intestinal lamina propria MNC spontaneously secrete rheumatoid factors of different isotypes during 14 days of in vitro culture (9.7 ng/ml IgA RF, 11.6 ng/ml IgM RF and 64.6 ng/ml IgA anti-Fc (IgG)). In matched studies intestinal MNC isolated from normal large bowel exhibited significantly greater levels of RF synthesis and secretion in vitro than normal small bowel intestinal MNC. A large increase in spontaneous RF secretion was observed from Crohn's disease intestinal MNC (21.4 ng/ml IgA RF, 21.4 ng/ml IgM RF, and 108.15 ng/ml IgA anti-Fc (IgG)), when compared with normal controls. The amount of RF secreted was dependent on the amount of inflammatory activity of the bowel specimens, from which the MNC were isolated (198.3 ng/ml of IgA anti-Fc(IgG) from involved versus 50.0 ng/ml from matched non-involved tissue). Ulcerative colitis MNC released decreased amounts of RF (7.1 ng/ml IgA RF, 6.2 ng/ml IgM RF, and 42.3 ng/ml IgA anti-Fc(IgG)). These observations using isolated intestinal MNC may explain the findings of RF changes in the sera of inflammatory bowel disease patients. Our observations support the hypothesis of a heightened state of activation in normal intestinal lamina propria MNC, which is further increased in active Crohn's disease. The dissimilarities observed between Crohn's disease and ulcerative colitis may indicate fundamental differences in disease pathophysiology and will lead to further studies exploring intestinal immunoregulatory properties of RF. 相似文献
82.
Oral administration of antigens from intestinal flora anaerobic bacteria reduces the severity of experimental acute colitis in BALB/c mice 总被引:5,自引:0,他引:5
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Verdù EF Bercik P Cukrowska B Farre-Castany MA Bouzourene H Saraga E Blum AL Corthésy-Theulaz I Tlaskalova-Hogenova H Michetti P 《Clinical and experimental immunology》2000,120(1):46-50
Homeostasis between indigenous intestinal flora and host response may be broken in inflammatory bowel disease. The present study explores whether repeated oral administration of intestinal flora antigens can protect mice against dextran sodium sulphate (DSS)-induced colitis. Sonicates of Gram-positive, Gram-negative, or anaerobic resident bacteria isolated from mouse intestinal flora were fed to BALB/c mice by gastric gavage, with or without cholera toxin. After four weekly doses of 1 mg of these antigen preparations (or of PBS as control), DSS colitis was induced. One week later colitis was evaluated by clinical scores and histology. Mice fed a pool of the three sonicates had decreased inflammation scores (5 (1-14); median (range)) compared with PBS-fed control animals (15 (7-19); P < 0.05). Decreased inflammation was observed in mice fed anaerobic bacteria antigens (7 (6-11); P < 0.05 versus control), but not in mice fed a pool of Gram-positive and -negative sonicates (16 (12-16)). Inflammation scores of mice fed antigens with cholera toxin were similar to those of PBS-fed control animals. DSS-induced colitis can be suppressed by oral administration of normal intestinal flora antigens containing anaerobes. 相似文献
83.
目的了解湛江市农村人群肠道蠕虫感染现状。方法随机采集村民新鲜粪便,用直接涂片法及饱和盐水浮聚法检查虫卵,用盐酸左旋咪唑驱虫法检查感染钩虫种类。结果粪检190人,虫卵阳性78人,总感染率为41.1%。检出3种肠道蠕虫卵,其中钩虫感染率25.8%,蛔虫感染率12.1%,鞭虫感染率10.5%,有2种或3种虫卵阳性率为6.8%;不同地点各虫感染率不同;钩虫以50—70岁人群感染率较高,蛔虫、鞭虫以20岁以下人群常见;女性的钩虫感染率明显高于男性。药物驱虫后检获有十二指肠钩虫成虫、美洲钩虫成虫及雄性蛔虫,其中,十二指肠钩虫占钩虫比例87.4%,美洲钩虫占钩虫比例12.6%。结论湛江市农村人群感染蛔虫、鞭虫及钩虫常见,其中以钩虫感染最为严重。钩虫感染率较高与旱作生产生活方式密切相关。十二指肠钩虫在该地钩虫流行中占了重要地位。 相似文献
84.
Lymphoid cells in afferent and efferent intestinal lymph: lymphocyte subpopulations and cell migration.
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Gut wall emigrating cells have been characterized in the intestinal lymph. The intestinal lymph duct was cannulated in 6-month-old minipigs. Under non-restraining conditions the efferent lymph from the mesenteric lymph nodes was collected in seven normal animals. Lymph coming directly from the gut (afferent lymph) was also collected in 18 pigs after resection of the mesenteric lymph node chains 3 months previously. The intestinal lymph flow was similar in both groups (around 18 ml/h). The lymphoid cell yield was 1.2 +/- 1.0 x 10(6)/h in control animals, while in mesenteric lymph node resected pigs it was around 20 times higher (26.2 +/- 17.6 x 10(6)/h). In the gut-derived lymph 76.5 +/- 8.8% T lymphocytes were observed (CD4+, 48.1 +/- 15.5%; CD8+, 53.6 +/- 12.7%). The percentage of immunoglobulin-positive cells was lower (IgM+, 10.1 +/- 4.5; IgA+, 1.7 +/- 1.1). In 14 mesenteric lymph node resected pigs a mean of 5.6 +/- 3.1 x 10(8) lymphocytes from the gut lymph were labelled in vitro with a fluorescent dye and retransfused. The labelling index of fluorescent cells in the intestinal lymph increased rapidly and remained at a high level until 44 h after cell transfusion. A four-to-ten times lower labelling index was found in the spleen, various lymph nodes and Peyer's patches. Most of the recovered lymphocytes were T cells. This model provides access to the cell pool leaving the gut wall, thus allowing an examination of its role in the gastrointestinal tract and other mucosal-lined organs. 相似文献
85.
The aim of the study was to test the hypothesis that baroreceptor unloading increases jejunal fluid absorption rate via an α2-adrenergic effect on electrogenic active transport. In 13 chloralose-anaesthetized cats, the carotid sinus baroreceptors were isolated and perfused with arterial blood, and we studied the effects of a graded decrease in carotid sinus pressure on intestinal vascular resistance, net fluid absorption rate and the potential difference between the intestinal lumen and the peritoneal cavity (PD). Experiments were performed in seven control animals and in six animals pretreated with yohimbine, an α2-adrenergic antagonist, at a dose of 0.1 mg kg-I i.v. Yohimbine per se had no significant effects on systemic arterial pressure, intestinal vascular resistance, net fluid absorption rate or PD. In the control animals, baroreceptor unloading induced an increase in systemic arterial pressure, intestinal vascular resistance and net fluid absorption rate, and a decrease in the PD. Yohimbine pretreatment did not significantly affect the systemic blood pressure response to baroreceptor unloading, but abolished the effect on intestinal vascular resistance and PD. After yohimbine treatment, decreases in carotid sinus pressure still enhanced net fluid absorption rate, but this response was observed in a higher range of carotid sinus pressures than in control animals. We conclude that (1) a major component of the increase in jejunal absorption rate during baroreceptor unloading is due to a non-electrogenic mechanism, which may be either active or passive; (2) this component of the response is not blocked by yohimbine at a dose sufficient for an effect on presynaptic α2-receptors; (3) the absorptive response to baroreceptor unloading is not a phenomenon secondary to the concomitant jejunal vasoconstriction. 相似文献
86.
用31具成人正常肝标本人工镂空,赛璐璐灌注正常新鲜尸肝6具,观察和测量了1~3级肝管长度、周径和夹角以及与肝动脉、门静脉相互关系;正常尸肝15具和30例肝内胆管结石并狭窄的肝标本,光镜观察各级肝管壁组织结构和病理改变。讨论了胆管结石存在部位,高位肝管剖开取石和行胆肠吻合术的术式选择及注意事项。 相似文献
87.
W H Berrettini J I Nurnberger P Hotvedt S Simmons-Alling E S Gershon 《Journal of affective disorders》1985,8(1):55-59
In an attempt to evaluate the role of VIP in affective disorder, measurements of lymphocyte VIP receptors, and plasma and CSF VIP levels were made in unmedicated and lithium-treated euthymic bipolars and controls. Lithium decreased plasma (P = 0.01) and CSF (P = 0.05) VIP levels and increased the affinity (decreased the KD) of the VIP lymphocyte receptor (P less than 0.01). This effect may be relevant to the psychotropic action of lithium in manic-depressive illness. 相似文献
88.
A. P. Avtsyn V. A. Shakhlamov R. S. Trager N. A. Kalinina I. R. Balyn' T. B. Timashkevich G. P. Polyakova 《Bulletin of experimental biology and medicine》1976,82(1):1045-1048
In a series of experiments 2250 tadpoles were infected with three strains of NAG vibrios. It can be concluded from the results of bacteriological and pathomorphological electron-microscopic and light-optical investigations that during the first 2 days the animals develop and recover from an acute infection, but the vibrios later persist for a long time in the body of the tadpoles and are excreted with the feces into the surrounding medium.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 7, pp. 841–843, July, 1976. 相似文献
89.
以基因表达谱芯片对Ty2 1a免疫前后小鼠肠细胞 (包括肠粘膜上皮细胞和肠上皮间淋巴细胞 )基因表达的差异性进行研究比较。将 490条经抑制消减杂交法筛选出的与小鼠Ty2 1a免疫相关的cDNA制备成表达谱芯片 ;利用免疫前后小鼠肠细胞的mRNA通过逆转录方法 ,将Cy3和Cy5两种荧光分别标记到两种组织的cDNA上 ,制备成cDNA探针 ,并与表达谱芯片进行杂交及扫描 ,单点重复 2次实验 ,通过计算机数据处理判定基因是否在上述两种细胞群中有表达差异。筛选出差异表达基因共 98条 ,其中 92条为表达上调基因 ,6条为表达降低基因。提示 ,基因表达谱芯片技术是高通量进行基因表达模式研究的方法 ,可同时定量研究大量的基因表达水平 ,从而鉴定可能参与免疫的基因。 相似文献
90.
P DESREUMAUX A LEVY J P VAERMAN M CAPRON A CORTOT J F COLOMBEL 《Clinical and experimental immunology》1996,104(2):293-296
The effects of nutrients on the mucosal immune system are poorly understood. The aim of this work was to study the cellular mucosal immune response to intrajejunal perfusion of an elemental diet (ED) or a control (C) electrolyte solution by measuring jejunal secretion of soluble CD4 (sCD4) and sCD8. sCD4 and sCD8 are markers of helper/inducer and suppressor/cytotoxic regulatory functions of T cells, respectively. A four lumen tube with a proximal occluding balloon at the angle of Treitz was used for jejunal perfusion in seven healthy volunteers (mean age 23 years). The length of the test segment was 40 cm. The jejunum was successively perfused with C for 80 min and then with ED containing 21.3g/l of free amino acids and 104.2g/l of oligosaccharides for 100 min. Jejunal fluid and serum concentrations of sCD4 and sCD8 were measured and their jejunal outputs calculated. When compared with C perfusion, jejunal perfusion with the ED resulted in a significant increase of sCD8 but not sCD4 jejunal secretion rates. sCD8 jejunal values increased early after ED perfusion and stayed at roughly the same level during the perfusion. Serum concentrations of sCD4 and sCD8 were not modified during ED perfusion. These data support the hypothesis that ED suppresses the immunologic tone of the gut, which could explain its beneficial effect in the management of intestinal inflammatory disease. 相似文献