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41.
The brains of pathogen-free autoimmune MRL/lpr, NZBWF1 and NZB mice were examined for central nervous system (CNS) inflammation in premoribund 8-week-old animals and at ages when active systemic lupus erythematosus (SLE) was present. CNS inflammation was observed only in MRL/lpr mice. Immunohistochemical studies of brains from young MRL/lpr mice found that infiltrates were composed primarily of CD4+ cells. Older MRL/lpr mice (22 and 26 weeks of age) had CD4+ cells predominantly, but CD8+ and B220+ cells were also present. Perivascular leakage of IgG was a prominent and unexpected finding in the MRL/lpr model. Congenic MRL/+ mice with late-onset autoimmunity had no inflammatory cells in brain tissue, and there was no perivascular staining with IgG or albumin. Our findings suggest that MRL/lpr mice are a useful model for studies of lupus-associated CNS inflammatory disease, and perivascular leakage may be a primary mechanism for entry of IgG into the brain.  相似文献   
42.
A technique whereby immune complexes (ICs) are detected in the CSF and serum from their inhibitory effect on the agglutination of IgG-coated latex particles by rheumatoid factor (RF) has been applied to patients with the following neurological diseases: multiple sclerosis (MS), inflammatory diseases, extradural peripheral neuropathies (EPN), CNS tumors, dementia, and a control group of other neurological diseases (OND). The groups did not differ significantly in respect of IC positivity either in CSF or serum. The MS group was tested for correlations between percentage of IC positives and CSF IgG/Albumin ratio on the one hand and presence of oligoclonal bands on isoelectric focusing on the other. The specificity of ICs to the dysimmune condition is discussed.
Sommario È stata applicata una tecnica di inibizione della reazione di agglutinazione del Fattore Reumatoide (RF) su particelle di latice, ricoperte di immunoglobuline umane, per il dosaggio degli immunocomplessi (ICs) nel liquor e net siero di pazienti affetti da malattie neurologiche. Sono stati considerati 5 gruppi di malattie neurologiche, rappresentate da: sclerosi multipla (MS), malattie infiammatorie, polinevriti, tumori del SNC, demenza ed un gruppo di controllo composto da malattie neurologiche miste (OND).Non sono state riscontrate differenze significative tra le percentuali di positività nei diversi gruppi esaminati, compreso il gruppo di controllo, tanto sul liquor che su siero.Particolare attenzione è stata posta allo studio della MS, ove la percentuale di positività degli ICs è stata raffrontata con il rapporto IgG/Albumina liquorale e con la presenza di bande oligoclonali IgG all'isoelectrofocusing (IEF).La specificità della formazione degli ICs in relazione alla situazione disimmune è stata inoltre discussa.
  相似文献   
43.
本文将聚乙二醇(PEG)比浊法和固相酶联免疫法(ELISA)结合,建立了—较灵敏的免疫复合物(IC)直接固相吸附抗原特异性检测法。利用牛清蛋白(BSA)为已知抗原组份的IC模型,分别对IC直接固相吸附的条件和影响因素、方法的灵敏度、重复性等进行了研究。结果发现IC在解离状态下直接固相吸附后的抗原特异性检测灵敏度明显高于未解离者。该法具有简单易行,灵敏度较高、适于临床测定大量血清样品等优点。  相似文献   
44.
腹茧症的影像诊断   总被引:1,自引:0,他引:1  
目的探讨腹茧症的影像特点,提高术前诊断水平。方法回顾性分析经手术病理证实的腹茧症6例,术前均进行立位腹部X线平片和腹部CT检查,4例同时行胃肠道钡剂造影,复习其影像表现。结果6例立位腹部X线平片中3例诊断为肠梗阻。4例胃肠道钡剂造影,均可见小肠交错盘绕成团,呈“菜花”状或“手风琴”状表现。6例CT检查,均可见小肠聚集成团,其周围可见膜样的囊状物将其包裹。结论对患者进行胃肠道造影时观察到“菜花”状征象,或CT检查时观察到小肠聚集成团被一层膜样物包裹,应考虑到腹茧症的可能。  相似文献   
45.
OBJECTIVE: In the present study, we evaluated the anti-inflammatory activity of Poria cocos (PoCo) on experimentally induced irritant contact dermatitis (ICD) in a repeated sodium lauryl sulphate (SLS) irritation model. METHODS: The anti-irritative effect of PoCo was evaluated with a visual score and quantified by non-invasive bioengineering methods, namely chromametry and transepidermal water loss. Three concentrations of PoCo in base cream DAC (amphiphilic emollient; German pharmacopoeia) were tested in a 4-day repetitive irritation test using SLS. RESULTS: A statistically significant anti-inflammatory activity was observed for PoCo by all three methods when applied in parallel to the induction period of ICD. Application of PoCo after induction of ICD once a day for 5 days, starting just at the end of 4 days, was without any effect. CONCLUSION: An anti-inflammatory efficacy of PoCo on the elicitation phase of the ICD induced by repeated SLS test could be observed and quantified by three independent, non-invasive biophysical assessment parameters. This effect can be explained by its influence on pro-inflammatory enzymes, namely phospholipase A2.  相似文献   
46.
BACKGROUND: CD40 has a role in the regulation of immune responses, cell proliferation and migration, and apoptosis. Little is known of its distribution in oral mucosal pathology. METHODS: Oral keratinocyte lines were tested for CD40 protein by Western blotting. Immunohistochemistry was used to stain paraffin sections of oral mucosa in health and in inflammatory, reactive, dysplastic and malignant disease. RESULTS: Western blotting confirmed the presence of CD40 in oral keratinocytes. CD40 was generally expressed by keratinocytes in the basal layer, with variable parabasal expression. Langerhans cells also stained positively. Expression was lost in nine of 33 (27%) epithelial dysplasias, seven of which were severe. Eighty-one percent of well, 69% of moderately and 50% of poorly differentiated oral squamous cell carcinomas (OSCC) expressed CD40. Overall, 45 of 65 (69%) OSCC were positive. The pattern of expression was unrelated to tumour differentiation. CONCLUSION: CD40 expression by basal and parabasal oral keratinocytes is physiological. Expression is lost in approximately one-third of oral epithelial dysplasias and OSCC. The significance of such loss remains unknown, but may be related to immunological or other abnormalities of keratinocyte homeostasis.  相似文献   
47.
Abstract The outcome of OLT for HBV-related liver disease is dependent on the prevention of allograft re-infection. Over the past decade, major advances have been made in the management of HBV transplant candidates. The advent of long-term hepatitis B immune globulin (HBIG) administration as a prophylaxis against HBV recurrence, and the introduction of new antiviral agents against HBV infection, such as lamivudine (LAM), were a major breakthrough in the management of these patients. Results of OLT for HBV infection are similar to those achieved with other indications. Pre-OLT antiviral treatment such as LAM can suppress HBV replication before OLT and thus decrease the risk of re-infection of the graft. Combination prophylaxis with LAM and HBIG after transplantation highly effectively reduces the rate of HBV re-infection, even in HBV replicative cirrhotic, patients. The optimal HBIG protocol in the LAM era is yet to be defined: dosing of HBIG, routes of administration, and possibility of stopping HBIG. Several antiviral drugs have been developed for the management of HBV infection on the graft, so outcome is currently good.  相似文献   
48.
BACKGROUND: Food allergy is a common disease without effective treatment. Since strict elimination of food allergens may be difficult, strategies for effective intervention are urgently needed. OBJECTIVE: The aim was to investigate the prophylactic use of orally administrated FIP-fve, an immunomodulatory protein isolated from the edible mushroom Flammulina velutipes, in a murine model of food allergy. METHODS: BALB/c mice were immunized twice intraperitoneally with ovalbumin (OVA), at an interval of 2 weeks. Before and during each period of immunization, FIP-fve (200 microg per mouse) or phosphate-buffered saline was given orally every other day with a total of five doses. Then OVA-specific antibodies and cytokine profiles were determined. Subsequently, the mice were orally challenged with OVA. Symptoms of anaphylaxis, levels of plasma histamine, and histology of intestines were examined. RESULTS: Mice receiving oral FIP-fve treatment during sensitization to OVA had an impaired OVA-specific IgE response with a Th1-predominant cytokine profile. These mice were protected from systemic anaphylaxis-like symptoms induced by subsequent oral challenge with OVA. CONCLUSION: Oral administration of FIP-fve has a Th1-skewing effect on the development of the allergen-specific immune response, and may serve the purpose of immunoprophylaxis for food allergy and other allergic diseases.  相似文献   
49.
Cdx2和PTEN在胃粘膜肠上皮化生及肠型胃癌组织中的表达   总被引:2,自引:0,他引:2  
目的:观察Cdx2及PTEN在胃粘膜病变中的表达。方法:以正常胃粘膜作为对照,用免疫组化的方法检测Cdx2和PTEN在胃粘膜肠上皮化生和肠型胃癌组织中的表达情况。结果:Cdx2在正常胃粘膜中没有表达,在肠上皮化生和肠型胃癌组织中明显增高,在肠型胃癌组织中Cdx2和PTEN水平显著低于肠上皮化生,两者表达模式相似。在不同类型肠化生中,小肠型肠化生Cdx2水平明显高于结肠型肠化生,而PTEN没有显著差异。结论:Cdx2为肠上皮化生的特异性标志物,并与PTEN在肠型胃癌的多步骤多阶段过程中可能起到重要作用,而PTEN可能对Cdx2的表达起到正相调节作用。  相似文献   
50.
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