Expulsion of allergen-containing materials from hydrated rye grass (Lolium perenne) pollen revealed by using immunogold field emission scanning and transmission electron microscopy

Background: Several studies demonstrated episodes of grass pollen–induced allergic asthma after heavy rainfalls. It has been hypothesized that these asthma attacks might be due to the release of respirable allergen-bearing particles from pollen cytoplasm. Objective: In this study we investigated the release mechanism of the most potent and frequently recognized grass pollen allergens, group 1 and group 5, from freshly harvested and subsequently hydrated rye grass pollen at the ultrastructural level. Methods: Rabbit antisera against purified recombinant group 1 and group 5 allergens were used to investigate, by using field emission scanning and transmission immunogold electron microscopy, the allergen release from rye grass pollen grains into isotonic aqueous solutions or water. Results: Pollen grains exposed to isotonic aqueous solutions remained intact and released allergens by means of diffusion. However, pollen grains hydrated in distilled water or rainwater expelled starch grains and cytoplasmic debris of respirable size. Group 1 and group 5 allergens were observed on and within these materials. Conclusions: Exposure of rye grass pollen to water leads to an expulsion of subcellular allergen-containing pollen components of respirable size. Our ultrastructural data thus support the idea that this release of allergen-containing respirable pollen materials may be a cause of asthma attacks after heavy rainfalls. (J Allergy Clin Immunol 2000;105:1140-5.)     

试论《雷雨》创作的感性直觉和理性把握

曹禺在《雷雨》的创作中对感性直觉和理性把握这一关系的处理 ,显示了恰到好处的艺术分寸感。剧作者独特而炽热的审美情感 ,充分体现了他创作过程中情感与形象的直觉性特征 ,剧本鲜明地留下了较之同时代人的更强烈、更广阔、更深厚的复杂感受的深深印痕。但曹禺又深谙艺术规律 ,在剧中对民族特色、个人风格、角色塑造以及情节结构所作的处理 ,又是极为注重理性把握的。一部《雷雨》 ,不仅靠情绪感受 ,更靠理性逻辑的运用 ,二者相依相存 ,既合“情” ,又合“理” ,“情”“理”交融而达到了新的戏剧境界。