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11.
Background Eosinophils are known to be main effector cells in allergic inflammation and IgA antibody has been shown to be a potent stimulus for eosinophil degranulation in in vitro conditions. Objective To evaluate the possible role of IgA antibodies on eosinophil degranulation in lower respiratory mucosa of asthmatics, we tried to find a correlation between total IgA and eosinophil cationic protein (ECP) levels in induced sputum from asthmatics. Methods We measured total IgA and albumin levels by nephelometry, and eosinophil cationic protein levels by Pharmacia CAP system in induced sputum from 23 atopic asthmatics and 12 healthy controls. Results IgA and albumin levels in induced sputum from asthmatics with sputum eosinophilia (sputum eosinophil count 5% of 200 counted non-squamous cells) were significantly higher (P < 0.05) than those from controls. However, IgA and albumin levels in induced sputum from asthmatics without sputum eosinophilia were not significantly different with those from controls (P > 0.05). In induced sputum from asthmatics, ECP levels were significantly correlated with albumin (r= 0.44, P= 0.04) and IgA levels (r= 0.67, P= 0.002). ECP/albumin ratio was also significantly correlated with IgA/albumin ratio (r= 0.61, P= 0.004). Conclusion Our results support the hypothesis that IgA antibodies in tracheobronchial secretion may be involved in eosinophil degranulation in asthma, and further study is needed to prove this hypothesis.  相似文献   
12.
Summary Acute leukaemia was complicated by pneumonia in 38 (34.8%) of 109 patients treated between 1979 and 1983; in 39.5% of the patients pneumonia occurred more than once. In 23 patients (60.5%) pneumonia occurred during cytostatic therapy, and 25 patients (65.8%) had less than 1000 mm2 granulocytes. Antibiotic therapy had no or only little effect in 70%. A total of 21 patients (55.3%) died of pneumonia. In 15 patients a direct relationship could be seen between pneumonia and the bacterial spectrum in the sputum. A prevalence of gram-negative bacteria was found (24 of 40 bacteria isolated, especially Enterobacteriaceae (19). Fungi were cultivated in 10 cases. Each of the typical pneumonia bacteria was only seen once respectively. It is most important that therapy begin immediately, even before the bacteria have been identified. Only then is there hope that the survival time of patients with acute leukaemia can be influenced.
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The inflammatory process in chronic obstructive pulmonary disease (COPD) is active mainly in the airways, but little is known about the properties of the inflammatory cells in this compartment. We have studied leucocytes in induced sputum of COPD patients compared to controls in order to uncover what types of macrophages might be involved in the disease. Sputum induction was performed by inhalation of nebulized sodium chloride solution. Leucocytes were isolated and stained with specific monoclonal antibodies for analysis in flow cytometry. Flow cytometry analysis revealed that a major portion of CD14+ macrophages in COPD has lower forward scatter, i.e. they are small macrophages. While in control donors these small macrophages accounted for 6.9% of all macrophages, the percentage of these cells in COPD was 45.7%. CD14 and HLA-DR expression was high on these small sputum macrophages while the large sputum macrophages expressed only low levels of these surface molecules, both in control donors and COPD patients. Small sputum macrophages of both control donors and COPD patients showed higher levels of constitutive tumour necrosis factor (TNF) compared to the large macrophages. TNF was inducible by lipopolysaccharide (LPS) preferentially in the small sputum macrophages in the control donors but there was no further induction in COPD patients. These data show that the small sputum macrophages are a major macrophage population in COPD and that these cells exhibit features of highly active inflammatory cells and may therefore be instrumental in airway inflammation in COPD.  相似文献   
15.
BACKGROUND: Studies suggest that nasal treatment might influence lower airway symptoms and function in patients with comorbid rhinitis and asthma. We investigated the effect of intranasal, inhaled corticosteroid or the combination of both in patients with both pollen-induced rhinitis and asthma. METHODS: A total of 262 patients were randomized to 6 weeks' treatment with intranasal fluticasone propionate (INFP) 200 microg o.d., inhaled fluticasone propionate (IHFP) 250 microg b.i.d., their combination, or intranasal or inhaled placebo, in a multicentre, double-blind, parallel-group study. Treatment was started 2 weeks prior to the pollen season and patients recorded their nasal and bronchial symptoms twice daily. Before and after 4 and 6 weeks' treatment, the patients were assessed for lung function, methacholine responsiveness, and induced sputum cell counts. RESULTS: Intranasal fluticasone propionate significantly increased the percentages of patients reporting no nasal blockage, sneezing, or rhinorrhoea during the pollen season, compared with IHFP or intranasal or inhaled placebo. In contrast, only IHFP significantly improved morning peak-flow, forced expiratory volume in 1 second (FEV1) and methacholine PD20, and the seasonal increase in the sputum eosinophils and methacholine responsiveness. CONCLUSIONS: In patients with pollen-induced rhinitis and asthma, the combination of intranasal and IHFP is needed to control the seasonal increase in nasal and asthmatic symptoms.  相似文献   
16.
BACKGROUND: About 70% of childhood asthmatics become free of asthma-related symptoms during adolescence. Little is known about bronchial hyperresponsiveness (BHR) and airway inflammation in young adults with "outgrown" childhood asthma. METHODS: We studied 61 nonsmoking medical students (18 intermittent mild asthmatics, 23 students with outgrown childhood asthma but free of asthma-related symptoms for 10 years (asymptomatic asthmatics) and 20 healthy students). BHR and lung function were measured, and induced sputum samples analyzed for eosinophil count, eosinophilic cationic protein (ECP), granulocyte-macrophage colony stimulating factor (GM-CSF), and tumor necrosis factor-alpha (TNF-alpha). RESULTS: BHR was still present in most asymptomatic asthmatics, but it was milder compared with healthy students. Only three subjects with previous asthma had no BHR and no signs of airway inflammation. Percentages of eosinophil, and ECP, TNF-alpha and GM-CSF concentrations in induced sputum of mild asthmatics and asymptomatic asthma groups were higher than in the healthy group. In asymptomatic asthmatics group, the duration of asthma, sputum eosinophil percentage, and the level of TNF-alpha in sputum correlated significantly with BHR. CONCLUSIONS: Only a few subjects with longstanding asymptomatic asthma could be considered as cured; most asymptomatic asthmatics continued to exhibit BHR and signs of airway inflammation. The outcome of childhood asthma and BHR was associated with the degree of airway inflammation and the duration of childhood asthma.  相似文献   
17.
BACKGROUND: Occupational asthma (OA) can be a debilitating disease even when removal from the workplace is achieved. Today, the "gold standard" in the assessment of OA is the bronchial provocation test (BPT). Induced sputum is a non-invasive method of exploring airway inflammation which can provide additional information about such challenges and thus could be applied in OA diagnosis and monitoring. METHODS: We report the study carried out in a grain worker sensitized to Lepidoglyphus destructor (Ld), who suffered from mild asthma at the workplace. Skin prick test and specific serum IgE were measured. Ld-BPT was performed, and the changes in eosinophil rates, and ECP and tryptase levels in induced sputum were studied 30 min and 18 h after Ld-BPT. We also determined the changes in nonspecific bronchial hyperresponsiveness (NSBH), given as PD20 values. To assess the specificity of the changes, we also carried out sputum induction and methacholine challenge after barley-BPT. RESULTS: An isolated immediate response was obtained with Ld-BPT, while barley-BPT was negative. Induced sputum showed higher tryptase levels 30 min after Ld-BPT, and higher eosinophil and epithelial cell percentages and ECP levels 18 h after Ld-BPT. There was also a decrease in methacholine PD20 values after Ld-BPT. Those changes were not observed after barley-BPT. CONCLUSIONS: The study of eosinophilic and mast-cell markers in induced sputum provides additional knowledge about the inflammatory process occurring in the airways, suggesting that the study of induced sputum should be considered in the assessment of OA.  相似文献   
18.
目的 :探讨一氧化氮 -环磷酸鸟苷 (NO- c GMP)通路在支气管哮喘发病机制中的作用。方法 :给 10名健康人、13例缓解期哮喘病人及 2 9例发作期哮喘患者诱导痰液 ,检测诱导痰液中 NO2 - /NO3- 及 c GMP的水平。并对其中 11例哮喘发作期患者应用强的松 (30 mg/d) ,治疗 1周的前后进行自身对照研究。结果 :哮喘发作期患者 NO2 - /NO3-水平显著高于健康对照者 [(4 0 6 .34± 5 12 .18) μmol/L,(71.80± 10 0 .98) μmol/L,P<0 .0 1],应用激素后患者在症状、体征好转的同时 ,NO2 - /NO3-和 c GMP的水平均有明显下降 ,稳定期哮喘患者的 NO2 - /NO3-水平同正常人相比差异无显著性。结论 :NO- c GMP通路可能在哮喘的发病中起重要作用 ,诱导痰 NO2 - /NO3- 的测定是无创伤性检测哮喘气道炎症的一项简便易行的实用方法。  相似文献   
19.
目的 :探讨痰液诱导法在支气管哮喘 (哮喘 )患儿痰液细胞分析中的应用。方法 :6 0例哮喘患儿分为急性发作期组 (34例 )和哮喘缓解期组 (2 6例 ) ,2 5例健康儿童作为对照组。高渗盐水诱导儿童吐痰 ,瑞氏染色法进行痰液总细胞及细胞分类计数。结果 :3组最大呼气流量 (PEF)下降差异无显著性。哮喘急性发作期组痰液细胞总数(TCC)、嗜酸性粒细胞数 (E0 )、中性粒细胞数 (N)均显著高于哮喘缓解期组和正常对照组。结论 :痰液诱导法简便、安全、准确 ,通过痰液诱导分析哮喘患儿痰液细胞有临床实用价值。  相似文献   
20.
下呼吸道感染痰标本细菌学检查和耐药菌株的观察   总被引:1,自引:0,他引:1  
目的:为合理使用抗生素治疗下呼吸道感染提供细菌学指标。方法:采集痰标本1124份,其中经涂片染色镜检确定为下呼吸道感染痰标本346份,占总标本数的31,采用细菌培养法对346份痰标本进行病原学鉴定并做药敏试验。结果:经鉴定的标本中,涂片镜检213份找到细菌,206份培养出细菌,鉴定出菌株288株,其中22份标本分离出两种以上细菌,鉴定出的G^+菌对头孢菌素类、喹诺酮类敏感,对青霉素耐药;G^-菌对  相似文献   
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