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31.
BACKGROUND: The distribution of house dust mite allergen (Der p1) in living rooms with smooth floor coverings, as measured in the middle compared with the border of the floor was investigated. It was hypothesized that activity causes displacement of Der p1, from the middle towards the border. METHODS: Dust samples from the middle and border of 50 floors with smooth coverings were collected and analysed on Der p1 content in a standardized way. RESULTS: The Der p1 exposure expressed as per unit area (ng/m2) showed that border samples contained significantly more Der p1 compared with middle samples (median: 2.57 vs 0.27, respectively, P = 0.023). Presence of pets and presence of more than two inhabitants increased the difference. When expressed as per unit weight of dust (ng/g), significant differences were only detected when comparing Der p1 content of samples collected in households with three or more inhabitants [median: 2 (border) vs 53 (middle), respectively; P = 0.035]. CONCLUSIONS: The Der p1 is unequally distributed on living room floors with smooth coverings, most likely because of displacement of dust from the middle towards the border due to activity. Expression as ng/g of dust and ng/m2 could not obviously be interchangeable. 相似文献
32.
Interaction of human lung surfactant proteins A and D with mite (Dermatophagoides pteronyssinus) allergens 总被引:4,自引:0,他引:4
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J Y WANG U KISHORE B L LIM P STRONG K B M REID 《Clinical and experimental immunology》1996,106(2):367-373
Human lung surfactant proteins A (SP-A) and D (SP-D) are both collagenous C-type lectins which appear to mediate antimicrobial activity by binding to carbohydrates on micro-organisms and to receptors on phagocytic cells. Purified native SP-A and SP-D, isolated from human bronchoalveolar lavage fluid, were found to bind to whole mite extracts (Dermatophagoides pteronyssinus) and the purified allergen Der p I, in a carbohydrate-specific and calcium-dependent manner. Binding was inhibited by ethylenediamine tetra-acetic acid (EDTA) as well as by maltose in the case of SP-D, or mannose in the case of SP-A. A recombinant polypeptide, which trimerized to form the neck region and carbohydrate recognition domains of SP-D, also inhibited the binding of native SP-D to the whole mite extract and Der p I. Both SP-A and SP-D did not bind to deglycosylated whole mite extracts or to recombinant Der p proteins, which lacked carbohydrate residues. These results suggest that the ability of surfactant proteins to bind certain allergens is mediated through their carbohydrate-recognition domains (CRDs) interacting with carbohydrate residues on the allergens. Moreover, SP-A and SP-D were found to inhibit allergen-specific IgE binding to the mite extracts either via steric hindrance or competitive binding. It is therefore possible that SP-A and SP-D may be involved in the modulation of allergen sensitization and/or the development of allergic reactions. 相似文献
33.
Relationships between allergic inflammation and nasal airflow in children with persistent allergic rhinitis due to mite sensitization 总被引:1,自引:0,他引:1
BACKGROUND: Allergic rhinitis is associated with Th2-dependent inflammation. Nasal obstruction is the most typical symptom in children with mite allergy. OBJECTIVES: The aim of this study was to evaluate the possible relationships among nasal symptoms, allergic inflammation, including inflammatory cells and cytokine pattern, and nasal airflow in children with persistent allergic rhinitis because of mite sensitization. METHODS: Twenty children (13 males and seven females, mean age 13.4 +/- 1.6 years) with persistent rhinitis because of mite allergy were evaluated. All of them had moderate-severe grade of nasal obstruction. Total symptom score (TSS), rhinomanometry, nasal lavage, and nasal scraping were obtained in all subjects. Inflammatory cells were counted by conventional staining; interleukin (IL)-5, and IL-8 were measured by immunoassay on fluids recovered from nasal lavage. RESULTS: Eosinophils were significantly associated with TSS (R = 74.4%, P = 0.0002), with IL-5 (R = 90.6%, P < 0.0001) and with nasal flow (R = -69%, P = 0.0007), but not with IL-8 (R = 0.1%, P = 0.995). Eosinophil levels were shown to independently predict nasal flow (P < 0.001), with flow decreasing linearly for increasing eosinophils, together with a significant effect of neutrophils (P = 0.016, linear increase in flow) and a borderline effect of IL-8 (P = 0.063, linear increase in flow). CONCLUSIONS: This study demonstrates the close association between IL-5 concentration and eosinophil infiltration. In addition, there is clear evidence concerning the relationship between eosinophil infiltration and nasal airflow. Thus, nasal eosinophils can be regarded as the most important predictor of upper airway function. These findings constitute first evidence of the relationship between nasal airflow impairment and Th2-related eosinophilic inflammation in children with persistent allergic rhinitis because of mite sensitization. 相似文献
34.
人面部蠕形螨感染致病及其防治 总被引:8,自引:0,他引:8
蠕形螨(demodex)寄生于人面部可引起人面部蠕形螨病(demodicidosis),对人的美容和生活造成影响。本文就人面部蠕形螨感染致病及其防治的研究予以综述,以求为临床诊断和治疗面部蠕形螨病提供依据。 相似文献
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36.
云南省16个县(市)黄胸鼠体表恙螨种类调查 总被引:2,自引:1,他引:2
目的了解云南省黄胸鼠(Rattus flavipectus)体表恙螨的寄生、种类组成、优势种及其空间分布型.方法选取云南省16个县(市)作为调查点,在现场用鼠笼加食饵诱捕黄胸鼠,收集耳壳及耳窝全部恙螨,用Hoyer's液封片后在显微镜下分类、鉴定.恙螨种群的空间分布格局用分布型指数中的聚块指数(m*/m)测定.结果在所调查的16个县(市)中,从13个县(市)捕获黄胸鼠725只,共采集恙螨2 710只,经鉴定隶属3亚科10属42种.印度囊棒恙螨(Ascoschoengastia indica)、微板无前恙螨(Walchia micropelta)、李氏囊棒恙螨(A.leechi)、蒙大微恙螨(Microtrombicula munda)为优势螨种,其带螨率和螨指数较高,依次分别为6.8%、5.5%、3.9%、4.3%和1.65、0.64、0 43、0 42.结论黄胸鼠体表恙螨种类复杂,数量丰富,呈聚集型分布. 相似文献
37.
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39.
螨脱敏疗法在儿童哮喘防治中的作用 总被引:1,自引:0,他引:1
目的 观察舌下含服螨脱敏疗法在儿童哮喘防治中的辅助治疗作用。方法 将68例哮喘儿童随意分为3组,单纯舌下含服螨脱敏治疗组、舌下含服螨脱敏治疗 吸入皮质激素组及单纯吸入皮质激素组,对上述患儿进行12个月的临床观察,判定临床疗效,对肺功能最大呼气流量(PEF)及螨过敏原皮肤点刺试验进行前后对比。结果 3组患儿中,以舌下含服塔脱敏治疗 吸入皮质激素组疗效最佳,与其他两组比较,差异有显著性意义(P<0.05)。结论 舌下含服螨脱敏疗法作为吸入皮质激素的辅助治疗对于螨过敏的哮喘患儿有良好的治疗效果而且安全。 相似文献
40.
目的探讨淮北地区不同环境粉螨群落结构。方法选取仓储环境(储藏物和/或地尘)、人居环境(卧室或学生宿舍中的床尘及地尘)和工作环境(纺织厂和/或制药厂工作车间中的地尘)等3类不同环境,采样点各40个,每个采样点各采集样本2份,每份l0g。过筛后留取尘渣,进行粉螨的采集、分类、鉴定及计数以及数据分析。结果3类不同环境共检获粉螨31种,隶属于7科21属,多样性分析结果表明:3类环境的粉螨平均孳生密度最高的是仓储环境,为57.2±6.2%,物种数为24,物种丰富指数为2.42,多样性指数为1.35,均匀度指数为0.97。结论3类不同环境中粉螨的孽十密度及多样性差异较大。 相似文献