20-羟基蜕皮酮对棉铃虫免疫系统的影响

20-羟基蜕皮酮(20-hydroxyecdysone,20E)是昆虫生长发育的重要调节激素,其类似物RH2485常作为杀虫剂使用,对昆虫的影响全面而深刻。然而20E对昆虫免疫系统的影响作用至今我们仍了解较少。为探究20E在棉铃虫Helicoverpa armijera生长发育过程中对免疫系统的影响,本研究选取6龄取食期幼虫注射20E,采用半定量RT-PCR检测了24个棉铃虫体液免疫相关基因在脂肪体和血淋巴中的表达变化,并检测了20E对细胞免疫的影响,包括细胞吞噬能力、凋亡状况及细胞密度变化。结果显示20E处理后,在脂肪体和血淋巴中不同免疫基因对20E的响应不同;血细胞密度在处理12 h后增加2倍,24 h后减少近1/2,但其中浆血细胞密度相对增加,细胞间的粘连作用增强,吞噬率提高约15%,凋亡率升高。结果表明,20E对棉铃虫免疫系统有显著影响,其中对体液免疫的影响比较复杂,但对细胞免疫有明显增强作用。     

The Role of Ecotones in Emerging Infectious Diseases

Recognition of the significance of the boundary between ecological systems, often referred to as the ecotone, has a long history in the ecological sciences and in zoonotic disease research. More recent research in landscape ecology has produced an expanded view of ecotones and elaboration of their characteristics and functions in ecosystems. Parallel research on emerging infectious diseases (EIDs) and the causes of increased rates of pathogen transmission, spread, and adaptation suggests a correspondence between ecotonal processes and the ecological and evolutionary processes responsible for zoonotic and vector-borne emerging infections. A review of the literature suggests that ecotones play a role in a number of the most important EIDs. Yet these are the only diseases for which specific landscape ecological information exists in the literature or disease reports. However, the similar disease ecologies of these with about half of the approximately 130 zoonotic EIDs suggests ecotones, particularly their anthropogenic origination or modification, may be generally associated with ecotones and the global trend of increasing EIDs.