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91.
Allergoid immunotherapy is a new form of allergen immunotherapy allowing safe administration of high allergen doses. There is limited information on the effects of allergoid immunotherapy in children with allergic rhinitis. To investigate the immunological and clinical effects of allergoid immunotherapy in children with allergic rhinitis due to grass pollen allergy. Children with allergic rhinitis were assigned to allergoid immunotherapy (n = 27) or control (n = 26, no immunotherapy) groups. Children in the immunotherapy group received seven injections of grass pollen allergoid immunotherapy before grass pollen season and continued to receive maintenance immunotherapy for 27 months. All patients were offered a pharmacotherapy regimen to be used on demand during the pollen seasons. Clinical and laboratory parameters were compared between the immunotherapy and control groups. The rhinoconjunctivitis symptom-medication score and asthma symptom score were lower in the immunotherapy group after 1 yr of maintenance immunotherapy (p < 0.01 for both). Skin test reactivity and nasal reactivity as determined by nasal provocation testing for grass pollen were significantly decreased after 1 yr of immunotherapy (p < 0.001 for both). The seasonal increase in bronchial reactivity and nasal lavage eosinophil cationic protein levels were prevented after the first year of immunotherapy (p < 0.05 for both). The seasonal increase in immunoglobulin (Ig)E decreased (p < 0.05) and grass-specific IgG, IgG(1) and IgG(4) increased significantly already at the end of the seven-injection build-up therapy (p < 0.001, for all). Interleukin (IL)-4 levels in the culture supernatants showed a steady decline from baseline at first and second year of immunotherapy (p < 0.001) but remained unchanged in the control group. Allergoid immunotherapy is an effective method in the treatment of grass pollen-induced allergic rhinitis in children and prevents the seasonal increase in bronchial hyper-reactivity. Changes in specific IgE and IgG levels and decreased IL-4 production in peripheral blood mononuclear cell culture supernatants may account for the observed clinical effects.  相似文献   
92.
Antibody-mediated rejection (AMR) after liver transplantation is recognized in ABO incompatible and xeno-transplantation, but its role after ABO compatible liver transplantation is controversial. We report a case of ABO compatible liver transplantation that demonstrated clinical, serological and histological signs of AMR without evidence of concurrent acute cellular rejection. AMR with persistently high titers of circulating donor specific antibodies resulted in graft injury with initial centrilobular hepatocyte necrosis, fibroedematous portal expansion mimicking biliary tract outflow obstruction, ultimately resulting in extensive bridging fibrosis. Immunofluorescence microscopy demonstrated persistent, diffuse linear C4d deposits along sinusoids and central veins. Despite intense therapeutic intervention including plasmapheresis, IVIG and rituximab, AMR led to graft failure. We present evidence that an antibody-mediated alloresponse to an ABO compatible liver graft can cause significant graft injury independent of acute cellular rejection. AMR shows distinct histologic changes including a characteristic staining profile for C4d.  相似文献   
93.
目的探讨血小板第4因子(platelet factor 4,PF4)对5.0 Gy γ射线全身照射小鼠的骨髓基质细胞(bone marrow stromal cells,BMSCs)的保护作用,进一步探讨PF4对造血的辐射防护机制.方法30只雄性小鼠随机分为3组:①放射组,②PF4保护组,③对照组.小鼠照射前分别于26和20 h腹腔内注射PF4,每次剂量50 μg/kg.于照射后3 d取骨髓细胞体外培养,分别计数培养后3、7和14 d的骨髓基质细胞集落(CFU-F);在培养后10 d流式细胞仪检测细胞周期.结果3组中,照射组3 d的CFU-F数量与PF4保护组差异无统计学意义,7和14 d的CFU-F数量PF4保护组较照射组明显增加.流式细胞仪检测结果表明3组中照射组G0+G1期细胞明显高于其余两组,S,G2+M期细胞明显低于其余两组.结论PF4对照射小鼠的骨髓基质细胞有保护作用,促进造血重建.  相似文献   
94.
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
95.
BACKGROUND: Diffuse peritubular capillary (PTC) C4d deposition has been shown to be associated with relatively poor graft outcome. The significance of focal PTC C4d staining in the early post-transplant period is uncertain. METHODS: Sixty-five biopsies from 53 patients with acute rejection were graded (Banff '97 criteria), stained for C4d, monocytes and T cells, and divided into three groups according to PTC C4d: (i) focal C4d (F) (14 biopsies, 14 patients), (ii) diffuse C4d (D) (23 biopsies, 15 patients) and (iii) no C4d (N) (28 biopsies, 24 patients). The three groups were compared with respect to a variety of biopsy and clinical parameters including outcome. RESULTS: The incidence of transplant glomerulitis and glomerular monocyte infiltration were significantly greater in F (64% and 2.0+/-2.0) and D (57% and 3.4+/-2.0) than in N (11% and 0.2+/-0.2). A significantly higher proportion of F (93%) demonstrated acute cellular rejection (Banff '97 grade > or = 1A) than did D (35%). The F and D groups included significantly more females (50 and 67%, respectively) than did N (21%). The percentage of patients with a second or third transplant was higher in F (29%) and D (40%) than in N (8%) (P = 0.0589). The proportion of patients with glomerular filtration rate < 30 ml/min at 12, 24 and 48 months was higher in the D and F groups than in the N, and there was a statistically significant increasing trend in odds of this outcome occurring at 48 months across the three groups (D > F > N group) (P = 0.0416). CONCLUSION: The results suggest that the biopsy findings and clinical course in patients with focal PTC C4d staining are similar to those associated with diffuse C4d.  相似文献   
96.
本文用CCl_41.356g/kg和5.87g/kg分别对大鼠进行皮下和呼吸道静式染毒,为期8周亚急性中毒试验,研究临床常用血清肝酶指标的变化。结果发现:CCl_4除使大鼠体重增长减慢外,第1周起出现肝细胞脂变、浊肿,进而坏死、纤维增生和肝硬化;肝糖元及SHD酶活性减少或消失,G-6-P酶活性先升高后降低的病理形态和组织化学的改变。与此同时或稍后出现SGPT和SGOT活性升高,持续至第8周。停药两周,肝病理改变趋于恢复,SGPT和SGOT活性也恢复至接近正常,两肝酶与病理改变相平行。AKP酶活性第4周后才升高;ChE酶似有先升高后降低趋势,但无明显差异性;γ-GT酶变化不规则。提示CCl_4亚急性中毒时,SGPT和SGOT酶活性升高与肝损关系较密切,可作临床早期诊断指标。血清AKP和ChE酶亦一定程度反映肝损的发展情况,可供作临床观察病情发展的辅助指标。  相似文献   
97.
Serotonin (5-HT) is a mediator (through 5-HT1P receptors) of slow EPSPs in myenteric ganglia of the small intestine. The effect of 5-HT can be mimicked by elevating cAMP; therefore, we tested the hypothesis that the slow EPSP-like response to 5-HT is cAMP-mediated. Guinea pig gut was enzymatically dissociated; myenteric ganglia remained intact and were collected by filtration. Neurons in the isolated ganglia retained their ability to manifest the slow EPSP-like response to 5-HT. Exposure to 5-HT raised the ganglionic level of cAMP (ED50 0.3 μM). This effect was not antagonized by the 5-HT1P antagonist, N-acetyl-5-hydroxytryptophyl-5-hydroxytryptophan amide (100.0 μM), or mimicked by the 5-HT1P agonist, 5-hydroxyindalpine (10.0 μM). Increases in cAMP were also evoked by the 5-HT1 agonist, 5-carboxyamidotryptamine (10.0 μM), the 5-HT2 agonist, (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI; 1.0–10.0 μM), and by the 5-HT4 agonists, renzapride (1.0–10.0 μM) and 5-methoxytryptamine (1.0–10.0 μM); however, neither the 5-HT1/5-HT2 antagonists, spiperone, methysergide, and methiothepin, nor the 5-HT4 antagonist, tropisetron (ICS 205–930; 10.0 μM), were able to inhibit the rise in cAMP evoked by these compounds or by 5-HT (0.1–10.0 μM). The 5-HT-evoked elevation of cAMP was antagonized by ketanserin (10.0 μM), which also blocked the effects of 5-methoxytryptamine and DOI, but not those of renzapride. The effective concentration of DOI, however, was higher than that needed for activation of 5-HT2 receptors, and Northern analysis using a cDNA probe encoding the rat 5-HT2 receptor failed to reveal the presence of 5-HT2 mRNA in myenteric ganglia, although it hybridizes with mRNA of the right size in the guinea pig brain. Compounds that failed to change levels of cAMP or to antagonize the action of 5-HT included 8-hydroxy-di-n-propylamino tetralin, R58639, R88226, and sumatriptan. It is concluded that the receptor responsible for the 5-HT-induced rise in cAMP in ganglia isolated from the guinea pig myenteric plexus is not a known subtype of 5-HT receptor. Since the pharmacology of this novel receptor is different from that of the slow EPSP-like response to 5-HT, the receptor probably does not mediate the slow EPSP. © 1993 Wiley-Liss, Inc.  相似文献   
98.
Abstract A high frequency of serum complement component C4A deficiency may explain the higher prevalence and greater severity of systemic lupus erythematosus reported in Australian Aborigines. Inherited deficiencies of serum complement components C4A, C4B, and C2 were examined in two Australian Aboriginal populations from Darwin and Alice Springs and compared with the prevalence of complement deficiencies in white Australian blood donors. The frequency of C4A deficiency alleles was 29% in Darwin Aborigines compared with 12% in Alice Springs and 17% in Canberra blood donors. Partial C4B deficiency was also higher in Darwin Aborigines than in the other populations. Inherited deficiency of serum complement component C2 was not observed.  相似文献   
99.
转hCTLA4Ig树突状细胞诱导T细胞免疫耐受的实验研究   总被引:2,自引:0,他引:2  
目的 通过逆转录病毒载体将人CTLA4Ig转染DCs ,探讨转人CTLA4Ig(hCTLA4Ig)树突状细胞 (DCsRev)诱导T细胞免疫耐受的可能性。方法 通过重组逆转录病毒将目的基因hCTLA4Ig转染到大鼠骨髓来源的DCs中 ,通过流式细胞检测目的基因hCTLA4Ig表达及DCs表面分子的改变 ;通过混合淋巴细胞反应 (MLR)检测DCsRev抑制T细胞免疫反应的能力。 结果 重组逆转录病毒转染DCs的最大效率为 91 2 5 % ;在功能上 ,DCsRev不但丧失了刺激MLR的能力 ,并且能够强烈抑制MLR中反应T细胞的增殖 ,而且抑制率与加入DCsRev的数量和DCsRev预处理反应T细胞的时间长短有关。具体来说 ,DCsRev数量在 10 3 ~ 10 4之间时 ,抑制率与剂量呈正相关 ,最高为 71 96%。而当DCsRev数量达到 5× 10 4抑制率下降为 5 9 2 %。在 12~ 48h之间 ,随着预处理时间的延长 ,抑制率却不断下降 ,预处理 12h抑制率最高 ,为 99 6%。但不做预处理 ,在反应开始时同时加入DCsRev ,则抑制率明显降低 ,仅为 5 9 2 %。对腹腔注射DCsRev大鼠脾T淋巴细胞体外分析表明 ,DCsRev也能在动物体内诱导耐受 ,但这种免疫耐受状态不能维持终身。结论 通过逆转录病毒载体将人CTLA4Ig转染DCs,不但DCs表面CD86分子被CTLA4Ig有效的封闭 ,并且能够诱导抗原特异性T细胞的免疫耐受  相似文献   
100.
It has been previously demonstrated that the generation of measles virus (MV)-specific cytotoxicity (CTL) is reduced in patients with multiple sclerosis (MS). By contrast, CTL specific for influenza virus (FLU) and mumps virus is normal. It is uncertain if reduced CTL is limited to MV in MS patients, or if reduced CTL may be found to other viruses as well. Since MV-specific CTL is predominantly restricted by HLA class II molecules, while FLU-specific and mumps-specific CTL have large HLA class I-restricted components, reduced MV-specific CTL may reflect a broader reduction in HLA class II-restricted CTL in patients with MS. To examine this question we studied the generation of CTL specific for herpes simplex virus type I (HSV). HSV-specific CTL, like MV-specific CTL is predominantly restricted by HLA class II molecules. We found that patients with MS had reduced generation of CTL to both MV and HSV. Most, but not all patients who had reduced generation of CTL to one virus also had a similar impairment with respect to the second virus. Some patients, however, had a reduction in the generation of CTL only to MV or to HSV. These findings extend our earlier observations regarding reduced MV-specific CTL in patients with MS to a second HLA class II-restricted virus, HSV. Such a reduction may reflect discrete impairments in immune function to separate viruses, possibly those that are associated with viral persistence, or may reflect a more generalized defect in HLA class II-restricted CTL.  相似文献   
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