红霉素对哮喘豚鼠嗜酸性粒细胞凋亡的影响

目的探讨红霉素对哮喘豚鼠嗜酸性粒细胞凋亡的影响。方法用卵白蛋白致敏复制哮喘豚鼠模型,分为哮喘组、地塞米松治疗组,及小、中、大剂量红霉素组6组。检测各组豚鼠支气管肺泡灌洗液(BALF)中白细胞总数、嗜酸性粒细胞(EOS)总数、EOS百分数,分离纯化BALF的EOS,用吖啶橙/溴乙啶(AO/EB)荧光染色法检测EOS凋亡率。结果①豚鼠BALF白细胞总数、EOS总数及EOS百分数哮喘组均明显高于正常对照组,各红霉素组与哮喘组相比均有所降低,但小剂量红霉素组与之相比差异无显著性;②豚鼠BALF中EOS凋亡率哮喘组明显低于正常对照组,各红霉素组均高于哮喘组,但小剂量红霉素组与之相比差异无显著性;③EOS凋亡率与BALFEOS总数及EOS百分数呈显著负相关。结论红霉素具有一定的抗气道非特异性炎症作用,可以诱导EOS凋亡,这可能是其抗哮喘炎症作用的主要机制之一。     

Association of Airway Inflammation with Asthma Control Level Evaluated by the Asthma Control Test

Background. The association between airway inflammation and asthma control level is not clear at present. Objective. This study aimed to explore the association by using induced sputum and asthma control status as determined by the Asthma Control Test (ACT). We also evaluated the association between the scores for each ACT question item and eosinophilic or neutrophilic airway inflammation. Methods. The ACT and sputum induction were performed at the same time. Associations between total scores or scores for each question item and sputum eosinophil or neutrophil counts were examined. The study was approved by an Institutional Review Board. Results. Of the 101 patients with chronic asthma enrolled, data from 98 (controlled n = 66, uncontrolled n = 32) were analyzed [60.0 years (43.0–68.0) M:F = 34:64]. Current control status determined by the ACT was not significantly associated with eosinophilic or neutrophilic inflammation. Among the ACT items, only nocturnal symptoms were associated with sputum eosinophils: patients with a positive answer to the question had significantly higher eosinophil counts than patients with a negative answer [5.4 (2.2–17.6) versus 2.1 (0.7–7.3), respectively, p = 0.08]. Furthermore, significant correlation was found between eosinophil counts and the scores for nocturnal symptoms (rs = ?0.218 p = 0.031). On the other hand, patients with rescue use of a short-acting b2-agonist (SABA) had significantly higher sputum neutrophil counts than non-SABA users [73.4 (52.8–83.4) versus 61.0 (36.3–74.8), respectively, p = 0.031]. The other ACT items were not significantly associated with sputum neutrophils. The neutrophil count correlated significantly with the frequency of rescue SABA use (rs = ?0.218 p = 0.031). Conclusions. Asthma control level evaluated by the ACT was not associated with airway eosinophilic or neutrophilic inflammation. However, the frequency of nocturnal symptoms was associated with sputum eosinophilia, and the frequency of rescue SABA use was associated with sputum neutrophilia.     

Eosinophil cationic protein in infants with respiratory syncytial virus bronchiolitis: predictive value for subsequent development of persistent wheezing

Infants with acute bronchiolitis during the first months of life are at increased risk of developing persistent wheezing and bronchial asthma later in life. The study of eosinophil cationic protein (ECP) suggests that eosinophil-related inflammatory mechanisms may play a role in respiratory syncytial virus (RSV) bronchiolitis. The aim of our study was to verify whether serum ECP (s-ECP) measurements are useful in predicting the development of persistent wheezing in children affected by RSV bronchiolitis during a 5 years follow-up period. Forty-eight infants were enrolled prospectively (mean age: 153.5 days). All had a clinical and radiological diagnosis of acute bronchiolitis and confirmed RSV infection. Peripheral eosinophil counts, levels of s-ECP, and serum IgE concentrations were measured during bronchiolitis. Five years later the children were re-evaluated in regard to their respiratory symptoms (standardized questionnaires) and atopic status (specific IgE levels). We observed significantly higher s-ECP levels (P < 0.001) at enrollment in subjects who developed persistent wheezing compared to subjects who did not show late wheezing. Initial s-ECP values allowed significant and correct prediction of persistent wheezing (P < 0.001). The risk to develop respiratory symptoms was 9.73 higher for infants with s-ECP levels > or = 8 microg/L than for those with s-ECP levels <8 microg/L (P < 0.0001). In conclusion, our study suggests that s-ECP levels in infants with bronchiolitis are useful in predicting the risk to develop wheezing in the subsequent 5 years.     

Clinical presentation and diagnostic sensitivity of laboratory tests for Strongyloides stercoralis in travellers compared with immigrants in a non-endemic country

OBJECTIVES: To assess whether the clinical and laboratory methods for diagnosing Strongyloides stercoralis infection in non-endemic countries is different between those who are chronically exposed and those who travel. METHODS: Analysis of laboratory and clinical data from 204 patients having S. stercoralis infection at the Hospital for Tropical Diseases, London. RESULTS: Sixty-four travellers and 128 immigrants from endemic countries had laboratory-proven strongyloides. In those with microscopically proven disease, serology was 73% sensitive in travellers and 98% sensitive in immigrants (P < 0.001). There was no difference in the eosinophil count between the two groups with 19% having a normal count. Patterns of symptoms varied between the groups, and around one-third were asymptomatic in both groups. Serology was of limited use in follow-up. CONCLUSIONS: Eosinophil count and stool microscopy are insufficiently sensitive to be used alone for screening strongyloides. The sensitivity of serology is good in immigrants with chronic infection, but lower in travellers.