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1.
Ceramide synthases (CerS) synthesise ceramides of defined acyl chain lengths, which are thought to mediate cellular processes in a chain length-dependent manner. In experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), we observed a significant elevation of CerS2 and its products, C24-ceramides, in CD11b+ cells (monocytes and neutrophils) isolated from blood. This result correlates with the clinical finding that CerS2 mRNA expression and C24-ceramide levels were significantly increased by 2.2- and 1.5-fold, respectively, in white blood cells of MS patients. The increased CerS2 mRNA/C24-ceramide expression in neutrophils/monocytes seems to mediate pro-inflammatory effects, since a specific genetic deletion of CerS2 in blood cells or a total genetic deletion of CerS2 significantly delayed the onset of clinical symptoms, due to a reduced infiltration of immune cells, in particular neutrophils, into the central nervous system. CXCR2 chemokine receptors, expressed on neutrophils, promote the migration of neutrophils into the central nervous system, which is a prerequisite for the recruitment of further immune cells and the inflammatory process that leads to the development of MS. Interestingly, neutrophils isolated from CerS2 null EAE mice, as opposed to WT EAE mice, were characterised by significantly lower CXCR2 receptor mRNA expression resulting in their reduced migratory capacity towards CXCL2. Most importantly, G-CSF-induced CXCR2 expression was significantly reduced in CerS2 null neutrophils and their migratory capacity was significantly impaired. In conclusion, our data strongly indicate that G-CSF-induced CXCR2 expression is regulated in a CerS2-dependent manner and that CerS2 thereby promotes the migration of neutrophils, thus, contributing to inflammation and the development of EAE and MS. 相似文献
2.
欧洲药品局(EMA)于2018年11月发布了"人用药品辅料右旋糖酐的包装说明书资料",该文件引用大量文献全面评价了右旋糖酐的安全性,特别指出含有右旋糖酐辅料的注射和吸入制剂的疫苗与药品,应在说明书中描述有关其过敏反应信息的新要求。介绍该文件的主要内容,期望对我国这类药品说明书的撰写和监管有所帮助。 相似文献
3.
目的了解长春西部地区过敏原特异性IgE分布情况。方法应用免疫印迹法检测1 258例患者的19种吸入性及食物性过敏原特异性IgE抗体,统计过敏原结果及种类。结果 1 258例患者,检出至少一种特异性IgE阳性率为34.0%。男性阳性率为33.5%;女性阳性率为34.5%。男女间阳性率差异无统计学意义(P> 0.05)。吸入性过敏原阳性率由高到低依次为:普通豚草14.2%、艾蒿11.4%、屋尘螨/粉尘螨8.1%、猫毛3.8%、狗上皮2.4%、柳树/杨树/榆树2.1%,屋尘1.6%、蟑螂1.6%、点青霉/分枝孢霉/烟曲霉/交链孢霉1.2%、葎草1.1%。食物性过敏原阳性率由高到低依次为:鸡蛋白2.9%、鳕鱼/龙虾/扇贝2.7%、牛奶2.3%、黄豆1.9%、蟹1.5%、虾1.3%、牛肉1.2%、花生1.0%、羊肉0.8%。混合过敏达到了相当高的比例。结论长春西部地区吸入性过敏原以普通豚草、艾蒿和屋尘螨/粉尘螨为主;食物性过敏原以鸡蛋白、鳕鱼/龙虾/扇贝、牛奶为主,明确过敏原,对过敏性患者的预防和治疗有重大意义。 相似文献
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Özlem Keskin Ayfer Tuncer Gonul Adalioglu Bulent E. Sekerel Cansn Saçkesen Omer Kalayc 《Pediatric allergy and immunology》2006,17(6):396-407
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
6.
目的探讨T细胞非特异性活化在CNS脱髓鞘性疾病中的作用。方法分离实验性自身免疫性脑脊髓炎(EAE)易感性BALB/c小鼠外周血单个核细胞(PBMC),采用体外细胞培养方法在体外与碱性髓鞘蛋白(MBP)共培养,测定培养上清液中IFN-γ、NO水平。结果经MBP刺激的PBMC产生IFN-γ[(43.83±6.06)pg/mL]和NO[(180.76±20.75)μmol/L]明显增加,与对照组产生的IFN-γ[(28.52±2.18)pg/mL]和NO[(95.61±13.09)μmol/L]相比差异有统计学意义(P<0.01)。结论在CNS脱髓鞘性疾病发病过程中,活化的T细胞、单核细胞等分泌致炎细胞因子和其他有害物质增多。 相似文献
7.
Y. Graif A. Goldberg R. Tamir D. Vigiser S. Melamed 《Clinical and experimental allergy》2006,36(12):1532-1537
BACKGROUND: In allergic conditions, the degree of skin test reactivity does not always correlate with the severity of clinical symptoms. Additional factors may contribute to the reported symptom severity. OBJECTIVES: To investigate the association between the magnitude of the skin prick test (SPT) response and the reported symptom severity in patients with allergic rhinitis and the possible modifying role of psychological factors. METHODS: One hundred four patients with allergic rhinitis and 23 with non-allergic rhinitis, classified according to their SPT response to 19 aeroallergens, were asked to rate the severity of five symptoms and to indicate whether their symptoms intensified on exposure to five common aeroallergens. They also completed a psychological questionnaire. Results Reported symptom severity of allergic rhinitis did not correlate with weal size for any of the aeroallergens tested or with the number of positive responses on SPT. It was not related to patient age, sex, or education. The reported symptoms severity correlated positively (0.29, P < 0.01) with reported symptom intensification on exposure to allergens. Moreover, both outcomes were positively associated with the psychological factors of hypochondriasis (0.20, P < 0.05 and 0.18, P < 0.05, respectively), and somatic awareness (0.24, P < 0.05 and 0.33, P < 0.01, respectively), but not with neuroticism. CONCLUSIONS: The severity of symptoms experienced by patients with allergic rhinitis is apparently not related to the magnitude of SPT response, but rather to psychological factors of hypochondriasis and somatic awareness. Physicians should be aware of the contribution of psychological factors to patient perceptions of the intensity of symptoms and of the intensification of symptoms on their exposure to allergens. 相似文献
8.
Local mucosal immunoglobulin E production: does allergy exist in non‐allergic rhinitis? 总被引:2,自引:0,他引:2
In this review, we critically evaluate the evidence for local IgE production in allergic rhinitis mucosa and the concept of local allergy in non-atopic idiopathic rhinitis. Significantly, fewer studies have focused on the disease pathways associated with non-allergic rhinitis compared with their allergic counterparts. Recently, there's been a revival of the hypothesis concerning the existence of local tissue-specific allergic disease confined to the nasal mucosa of some systemically non-atopic rhinitis subjects. Providing the evidence for local mucosal IgE production in allergic rhinitis is a pre-requisite to reviewing its existence in non-allergic rhinitis. In addition, practical and theoretical approaches useful in the detection of allergy in non-allergic rhinitis will be discussed. Furthermore, successful therapeutic regimens used in the treatment of non-allergic rhinitis will be examined as these could provide an insight into the underlying pathophysiology of this common but poorly understood disease. 相似文献
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