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91.
J. A. Sánchez-Mesa C. Galan J. A. Martínez-Heras† C. Hervás-Martínez† 《Clinical and experimental allergy》2002,32(11):1606-1612
BACKGROUND: Pollen allergy is a common disease causing hayfever in 15% of the population in Europe. Medical studies report that a prior knowledge of pollen content in the air can be useful in the management of pollen-related diseases. OBJECTIVES: The aim of this work was to forecast daily Poaceae pollen concentrations in the air by using meteorological data and pollen counts from previous days as independent variables. METHODS: Linear regression models and co-evolutive neural network models were used for this study. Pollen was monitored by a Hirst-type spore trap using standard techniques. The data were obtained from the Spanish Aerobiology Network database, University of Cordoba Monitoring Unit. The set of data includes a series of 20 years, from 1982 to 2001. A classification of the years according to their allergenic potential was made using a K-mean cluster analysis with pollen and meteorological parameters. Statistical analysis was applied to all the years of each class with the exception of the most recent year, which was used for model validation. RESULTS: It was observed that cumulative variables and pollen values from previous days are the most important factors in the models. In general, neural network equations produce better results than linear regression equations. CONCLUSION: Co-evolutive neural network models, which obtain the best forecasts (an almost 90% "good" classification), make it possible to predict daily airborne Poaceae pollen concentrations. This new system based on neural network models is a step toward the automation of the pollen forecast process. 相似文献
92.
Fukuda S Midoro K Gyoten M Kawano Y Ashida Y Nabe T Kohno S Nagaya H 《European journal of pharmacology》2003,476(3):239-247
TAK-427 (2-[6-[[3-[4-(diphenylmethoxy)piperidino]propyl]amino]imidazo[1,2-b]pyridazin-2-yl]-2-methylpropionic acid dihydrate) is a novel anti-allergic agent that has both histamine H1-receptor antagonist and anti-inflammatory activities. In this study, we evaluated the efficacy of TAK-427 on acute nasal responses and nasal obstruction using various guinea pig models of allergic rhinitis. TAK-427 inhibited the histamine-induced nasal reactions with an ID50 value of 0.633 mg/kg, p.o. TAK-427 (0.1-10 mg/kg, p.o.) and most histamine H1-receptor antagonists tested inhibited the increase in intranasal pressure, nasal hypersecretion, sneezing and nasal itching caused by a single antigen challenge in sensitized guinea pigs. In addition, TAK-427 (0.3, 30 mg/kg, p.o.) significantly inhibited the development of nasal obstruction when sensitized guinea pigs were repeatedly challenged via inhalation with Japanese cedar pollen, whereas the histamine H1-receptor antagonist, azelastine (1 mg/kg, p.o.), and ketotifen (1 mg/kg, p.o.) were without effect. These results suggest that TAK-427 might not only suppress acute nasal symptoms but also ameliorate nasal obstruction via the effects other than those as a histamine H1-receptor antagonist. 相似文献
93.
目的:研究药用菊花不同栽培类型花粉形态特征,以便为药用菊花的孢粉学研究提供资料,并为优质品种的建立和规范化种植(GAP)提供参考依据。方法:利用扫描电镜对药用菊花12个栽培类型的花粉形态进行观察和比较。结果与结论:花粉粒长球形,赤道面观椭圆形,极面观3裂圆形,具3萌发沟,外壁表面具刺状雕纹,但不同栽培类型之间存在差异,这为优质品种的筛选提供了参考依据。 相似文献
94.
Jonathan Witonsky Ryan Abraham Jennifer Toh Tulsi Desai Mili Shum David Rosenstreich 《The Journal of asthma》2013,50(9):927-937
Objective: To better understand how meteorological variables, air quality variables, and pollen counts collectively contribute to asthma-related emergency department visits (AREDV) and asthma-related hospitalizations (ARH) among pediatric and adult patients in the New York City borough of the Bronx. Methods: The numbers of daily adult and pediatric AREDV and ARH from 2001 to 2008 were obtained from three Bronx hospitals. After removing outliers, interpolating missing data, and standardizing variable values by scaling the data using z-scores, data were analyzed using Spearman rank tests and linear regression models for the full year and each season. Results: There were a total of 42,065 AREDV and 1,664 ARH at both Bronx hospitals. With the exception of a spring peak in AREDVs, AREDVs and ARHs follow a cyclical pattern, climbing in the fall, plateauing in the winter, dropping in the spring, and reaching a low in the summer. Among the 11 air quality, meteorological, and pollen count variables, temperature and tree pollen made the greatest contribution to AREDV with scaled coefficients of –0.337 and 0.311 respectively; equating to an additional AREDV for every 5.0-unit decrease in temperature and an additional AREDV for every 186.0-unit increase in tree pollen. These two variables were confirmed to have independent associations with AREDV prior to the data interpolation. Grass pollen was also found to have a relatively large contribution to AREDV during the summer with a scaled coefficient of 0.314, equating to an additional AREDV for every 2.3-unit increase in grass pollen. Conclusion: There are distinct peaks of increased AREDVs that are closely associated with increased tree pollen counts in the spring and decreasing temperatures in the fall. Early anticipation of these air quality, meteorological, and pollen factor changes based on ongoing surveillance could potentially guide clinical practice and minimize AREDVs in the Bronx. 相似文献
95.
S. A. Lewis J. M. Corden G. E. Forster & M. Newlands 《Clinical and experimental allergy》2000,30(12):1724-1732
BACKGROUND: The effect of outdoor aeroallergen exposure in asthma may be enhanced by air pollutants, including ozone, nitrogen dioxide and particulates, and by certain weather conditions. It is not yet established whether these interactions are important in determining asthma morbidity at the population level. OBJECTIVE: We have investigated the joint effects of aeroallergens, rainfall, thunderstorms and outdoor air pollutants on daily asthma admissions and Accident and Emergency (A & E) attendance using routinely collected data between 1993 and 1996 from Derby in central England. METHODS: Daily counts during the aeroallergen season of grass and birch pollen, basidiospores, Didymella, Alternaria and Cladosporium, maximum 1 hour ozone and nitrogen dioxide and daily average black smoke measurements, all made in the vicinity of the city centre, were categorized in tertiles. Rainfall was classified as dry, light (= 2 mm) or heavy (> 2 mm). The modifying effect of outdoor pollutant levels, and rainfall or the occurrence of a thunderstorm, upon the effects of individual aeroallergens on asthma admissions and A & E attendance were investigated by fitting appropriate interactions in log linear autoregression models with adjustment for potential confounders. RESULTS: We found a significant interaction between the effects of grass pollen and weather conditions upon A & E attendance, such that the increase with grass pollen count was most marked on days of light rainfall (adjusted rate ratio for >/= 50 vs < 10 grains/m3 at lag 2 days = 2.1, 95% CI 1.4, 3.3). Asthma admissions increased with Cladosporium count. We found no statistically significant interactions between effects of any individual aeroallergen and outdoor air pollutant upon either measure of asthma morbidity. CONCLUSIONS: Rainfall and thunderstorms are important effect modifiers in the relation between grass pollen and measures of acute asthma morbidity. Interactions between ambient levels of aeroallergens and chemical pollutants in the Derby area do not play a major role in determining asthma admissions and A & E attendance. 相似文献
96.
P. Chakraborty I. Chowdhury S. Guptabhattacharya S. Chanda S. Gupta D.N. Sengupta 《Allergy》1999,54(9):985-989
BACKGROUND: This study highlights the allergenicity and allergenic components of the pollen of Phoenix sylvestris Roxb. (PS), or date sugar palm, which is predominantly airborne in the air of Greater Calcutta. METHODS: A 2-year aerobiologic survey was performed by Burkard sampler. PS pollen extract was used in skin tests of allergic patients, fractionated by (NH4)2SO4 and the Sephacryl S-200 column. The allergenicity of each fraction was checked by skin test and IgE ELISA inhibition. The principal allergenic fraction, Fr.lla, was separated in 11% SDS-PAGE, and its allergenicity was confirmed by IgE ELISA inhibition and immunoblotting. RESULTS: PS pollen grains were found to be prevalent in the air of the suburban zone of Calcutta from January to March with a peak in February. The pollen extract showed high (44.07%) positive skin reaction on 540 respiratory allergic patients. Among the (NH4)2SO4 cut fractions, Fr.II was the most active one, and it was resolved into four subfractions in the Sephacryl S-200 column. Fr.lla was the principal allergenic fraction, showing the presence of two components of 33 and 66 kDa in SDS-PAGE. In IgE immunoblotting, both of the components were found to be allergenic. CONCLUSIONS: The PS pollen grain is an important aeroallergen from Calcutta, India. The 33- and 66-kDa components are the major allergens present in the relevant pollen extract. 相似文献
97.
目的:分析松黄蛋白抗原中致敏成分。方法:用硫酸铵沉淀、葡聚糖凝胶层析分离松黄蛋白质组分,以致敏大鼠腹腔肥大细胞组胺释放试验和被动皮肤过敏反应试验检测松黄蛋白组分的致敏活性。结果:松黄蛋白中含有3种抗原性不同的组分,组分Ⅱ是松黄主要抗原。结论:松黄蛋白中含有致敏组分,此蛋白组分具对热和酸碱不稳定的性质。 相似文献
98.
Birch Pollen Asthma in The Netherlands 总被引:4,自引:0,他引:4
The occurrence of birch pollen asthma is related to high birch pollen concentrations in the air, and therefore this type of asthma is rather common in Scandinavia. High birch pollen concentrations are rare in The Netherlands, but in the spring of 1984 extremely high levels were reached, whereas the concentrations of alder and hazel pollen were very low. During this period nine pollinosis patients known to the allergist developed asthmatic complaints. The appearance and disappearance of the asthmatic symptoms in these patients showed strong correlation with the course of the birch pollen concentration in the air, which strongly suggests that birch pollen asthma can occur in The Netherlands. The significance of this finding may be that this type of asthma can be observed regularly when the birch pollen concentrations are very high. This may also hold for other western European countries. 相似文献
99.
100.
Yasueda Saito Sakaguchi Ide Saito Taniguchi Akiyama & Inouye 《Clinical and experimental allergy》2000,30(4):546-550
BACKGROUND: Not only Cryptomeria japonica (Japanese cedar) pollen but also that of Chamaecyparis obtusa (Japanese cypress) induces the allergic symptoms of Japanese cedar pollinosis. However, allergens from C. obtusa pollen have not been as well characterized as those from C. japonica pollen. OBJECTIVE: We sought to identify and characterize a homologue of the second major allergen of C. japonica pollen, Cry j 2, from the pollen of C. obtusa. METHODS: An allergen homologous to Cry j 2 was identified in C. obtusa pollen extract by immunoblot analysis, probed with anti-Cry j 2 monoclonal antibodies and purified by a series of column chromatographic steps. RESULTS: The allergen isolated from the extract showed a slightly diffuse band of 45 kDa and closely spaced double-bands of 42 and 45 kDa on SDS-PAGE, under reducing and non-reducing conditions, respectively; the bands were approximately 5-7 kDa larger than those of Cry j 2. In 24 of 30 residues, the N-terminal amino acid sequence of the allergen was identical with corresponding sequence in Cry j 2. Most patients with pollinosis who were IgE antibody-positive to Cry j 2 were shown to be IgE antibody-positive to this allergen, and the IgE antibody levels to both allergens were highly correlated. CONCLUSION: The results indicate that the allergen isolated from C. obtusa pollen in this study is a homologue of Cry j 2. The allergen was designated as Cha o 2 according to the WHO/IUIS Allergen Nomenclature Subcommittee recommendation. 相似文献