Performance of the Coriolis air sampler,a high-volume aerosol-collection system for quantification of airborne spores and pollen grains

The Coriolis δ air sampler manufactured by Bertin Technologies (France) is a continuous air sampler, dedicated to outdoor monitoring of airborne spores and pollen grains. This high-volume sampler is based on patented Coriolis technology delivering a liquid sample. The air is drawn into a conical vial in a whirling type motion using suction; particles are pulled against the wall by centrifugal force. Airborne particles are separated from the air and collected in a liquid medium. This innovative solution allows rapid analysis by several techniques including PCR assay and serological assay in order to measure the antigenicity/allergenicity of pollen grains and fungal spores. Also, traditional counting of pollen grains or taxa identification by optical microscopy can be done. A study has been carried out by the Health Protection Agency (HPA), Porton Down, UK, to measure the physical efficiency of the Coriolis air sampler. The physical efficiency of the sampler for collection of micro-organism-laden particles of various sizes has been compared with that of membrane filter samplers using the techniques described by ISO 14698-1. The Coriolis was operated simultaneously with membrane filter samplers in a controlled room where they were challenged with uniform-sized particles of different diameters containing bacterial spores. For the larger particle sizes, it was found that the physical efficiency of the Coriolis was 92% for 10-μm particles. The biological performance of the Coriolis in the collection of airborne fungal spores and pollen grains was evaluated in comparison with a Hirst spore trap (one-week tape-on-drum type sampler) which is one of the most frequently used traps in the measurement of outdoor pollen grain concentrations. The advantages and limitations of both technologies are discussed. The Coriolis was operated simultaneously with a Hirst spore trap in the sampling station of Réseau National de Surveillance Aérobiologique, France (RNSA); the pollen grain and fungal spore counts were analysed by optical microscopy. The pollen grain count m⁻³ collected was compared for both devices. The dispersion values were obtained and statistical analysis was carried out. This study shows that the Coriolis air sampler provided equivalent recovery of pollen grain and fungal spores compared with the volumetric trap standard method (not significantly different, W test, α = 0.05). Nowadays, the French-led project, acronym MONALISA, with financial support from the European Commission––Life-Environment (LIFE05 ENV/F/000068), is testing this innovative air sampler in order to measure the antigenicity/allergenicity of the main aeroallergen particles, i.e. Betula (birch), Poaceae (grasses), Parietaria (pellitory), Olea spp (olive tree), and Artemisia (mugwort) pollen grains, and Alternaria (fungal spores) to validate a new approach of monitoring instead of quantifying pollen grains by their morphology. The robustness and efficiency of the MONALISA system is being demonstrated at a national level throughout Europe in eight different countries with different bio-climatic and topography characteristics: France, UK, Finland, Poland, Spain, Portugal, Switzerland, and Italy.     

我国四城市真菌特别调查

对我国北京、上海、广州、成都四城市３３个代表点的大气真菌及妇女内裤样品进行检测,共鉴定３２８８株丝状真菌和酵母,分属３２个属６２个种。测定四城市丝状真菌优势菌为枝孢属、链格孢属、青霉属、曲霉属,优势酵母菌为红酵母属、假丝酵母属、毕赤酵母属。     

PM_(2.5)致炎症作用及其机制研究进展

大气细颗粒物(PM2.5)能够深入下呼吸道,直达肺泡,并且能透过肺呼吸道屏障,进入循环系统,随血流而到达全身各靶器官,对其组织细胞造成伤害。除诱发呼吸系统疾病外,PM2.5还能致心血管疾病、糖尿病、恶性肿瘤等多种疾病的发生和发展。PM2.5致局部组织或系统的急性或慢性炎症、炎症细胞的浸润、炎症因子的异常表达与释放等,被认为是致人体健康损伤的重要机制。在综述PM2.5与炎症细胞的相互作用、炎症因子的表达与释放等致炎症效应新成果的基础上,概述了近年来人们对于PM2.5致炎症作用机制的新认识。     

MonitoringAspergillus fumigatus aerosols from a composting facility

The large, outdoor Islip Yard Waste Composting Facility on Long Island, New York was investigated as a source of airborne fungus spores. The Burkard-Hirst volumetric spore trap was used for the first extensive sampling of small mold spores for this application. Samplers were operated continuously from 21 August to 30 November 1992 in the facility and in a suburban community about 540 m from the facility. A control site approximately 10 000 m from the facility was also sampled to establish background levels of fungus spores. The facility site had higher average readings ofAspergillus fumigatus spores than did the community and both were higher than the control.A. fumigatus was the only fungus among 30 categories tracked that differed significantly between the facility and control sites. It was also isolated repeatedly from the compost. Higher average levels ofA. fumigatus were measured in the community when winds blew from the facility, and also during times when the compost was moved or mixed at the facility. No correlation was found between wind direction or work times andA. fumigatus conidia at the control site. The study shows that this compost facility can produce a measurable increase in the number of airborneA. fumigatus conidia both at the edge of the facility and at 540 m downwind. It also demonstrates that the Burkard spore trap can be used for monitoring small, airborne mold spores, but it is a difficult and labor intensive task.     

Enumeration of airborne molds in some indoor environments of Madras city (India) by cultural and non-cultural volumetric samplers

The air mycoflora of six indoor environments in Madras city (India) has been investigated by sampling air with an Andersen sampler and a Burkard personal sampler. Forty-eight species assignable to 24 genera were recorded by Andersen sampler. Spores belonging to 14 genera in addition toPenicillium andAspergillus were identified from Burkard trap slides. Species ofAspergillus, Penicillium, Mucor andRhizopus were most frequently isolated in considerable numbers. As a single genusAspergillus ranked first followed byPenicillium at some sites, andCladosporium at some other sites. The predominance ofPenicillium andAspergillus was also confirmed by Burkard trap data. Spores belonging toGanoderma, Nigrospora, Epicoccum, andTetraploa were recorded only by Burkard sampler, thereby suggesting the necessity of using two complimentary spore traps, cultural and non-cultural, in any aerobiological investigation.     

Limited spatial response to direct predation risk by African herbivores following predator reintroduction

Predators affect ecosystems not only through direct mortality of prey, but also through risk effects on prey behavior, which can exert strong influences on ecosystem function and prey fitness. However, how functionally different prey species respond to predation risk and how prey strategies vary across ecosystems and in response to predator reintroduction are poorly understood. We investigated the spatial distributions of six African herbivores varying in foraging strategy and body size in response to environmental factors and direct predation risk by recently reintroduced lions in the thicket biome of the Addo Elephant National Park, South Africa, using camera trap surveys, GPS telemetry, kill site locations and Light Detection and Ranging. Spatial distributions of all species, apart from buffalo, were driven primarily by environmental factors, with limited responses to direct predation risk. Responses to predation risk were instead indirect, with species distributions driven by environmental factors, and diel patterns being particularly pronounced. Grazers were more responsive to the measured variables than browsers, with more observations in open areas. Terrain ruggedness was a stronger predictor of browser distributions than was vegetation density. Buffalo was the only species to respond to predator encounter risk, avoiding areas with higher lion utilization. Buffalo therefore behaved in similar ways to when lions were absent from the study area. Our results suggest that direct predation risk effects are relatively weak when predator densities are low and the time since reintroduction is short and emphasize the need for robust, long‐term monitoring of predator reintroductions to place such events in the broader context of predation risk effects.     

Interaction of monocytes with tumor cells coated with complement with or without antibody

Raji, a human B lymphoblastoid cell line has the ability to activate the complement cascade by alternate pathway mechanisms with subsequent fixation of C3 to receptors on the Raji cell membrane. Using this property, we examined the role that complement plays in mediating a cytolytic event between human peripheral blood monocytes and Raji cells coated with C3b, antibody, or both. Presence of C3 was confirmed by immune adherence. IgG bound to the Raji membrane was quantitated using I¹²⁵ Staphylococcal protein A assay. The presence of alternate pathway-activated C3 on Raji cells failed to produce monocyte-mediated cytotoxicity. These same target cells subsequently coated with antibody concentration ranging from 200 to >600,000 SPA molecules per Raji cell produced neither enhancement nor inhibition of antibody-dependent, cell-mediated cytotoxicity (ADCC). ADCC was enhanced by complement when complement activation and binding of C3 to the cell surface occurred by classical pathway mechanisms. ADCC of 32% ± 3.2 occurred with undiluted antiserum (625,000 SPA molecules bound/Raji cell) with enhancement to 52% ± 1.1 in the presence of C3. IgG inhibition of ADCC was unaffected by the presence of membrane-bound C3.     

Gini coefficient predictions from airborne lidar remote sensing display the effect of management intensity on forest structure

In this study, two forest sites located in Finland were compared by means of predictions of Gini coefficient (GC) obtained from airborne laser scanning (ALS). We discuss the potential of the proposed method for identifying differences in structural complexity in relation with the management history of forests. The first study site (2200 ha), the Koli National Park (NP), includes areas where human intervention was restricted after 1907, in addition to forests which were protected only after the 1990s. The second study site in the municipality of Kiihtelysvaara (800 ha) has been under intensive management. These are commercial forests which include areas with different types of ownership: a large estate owned by an industrial company together with smaller private properties. We observed that GC predictions may be used to evaluate the effects of management practice on forest structure. Conservation and commercial forests showed significant differences, with the old-protected area of Koli having the highest, and the most intensively managed area in Kiihtelysvaara the lowest GC values. The effect of management history was revealed, as the 1990s’ extensions of Koli NP were more similar to unprotected areas than to forests contained within the original borders of the 1907s’ state property. Yet, their conservation status for almost two decades has been sufficient for developing significant differences against the outside of the NP. In Kiihtelysvaara, we found significant differences in GC according to the type of ownership. Moreover, the ALS predictions of GC also detected differences near lakeshores, which are driven by limitations on logging governed by Finnish law. Estimating this indicator with ALS remote sensing allowed to observe its spatial distribution and to detect peculiarities which would otherwise be unavailable from field plot sampling. Consequently, the method presented appears to be well suited for monitoring the effects of management practice, as well as verifying its compliance with legal restrictions.     

A comparison of airborne and dust-borne allergens and toxins collected from home,office and outdoor environments both in New Haven,United States and Nanjing,China

In this study, the airborne and dust-borne concentrations of endotoxin, (1,3)-β-d-glucan and five house dust allergens were measured in office, home, and outdoor environments both in New Haven, United States and Nanjing, China. Air samples were collected using a BioSampler at a flow rate of 12.5 l/min for 30 min. Dust samples were simultaneously collected using a surface sampler. Dust samples went through extraction and dilution before analysis, while air samples were analyzed directly. Limulus Amoebocyte Lysate (LAL) Pyrochrome and Glucatell assays were used to quantify endotoxin and (1,3)-β-d-glucan concentration levels, respectively. Enzyme-linked sorbent assay was used to measure the dust mites, cat, dog, and cockroach allergens. The experimental results indicated that endotoxin, (1,3)-β-d-glucan and allergen concentrations vary greatly both with samples and environments. In all tested environments, endotoxin concentration ranged from 0.8 to 83.7 ng/m³ for air, and 7.8 to 14.3 ng/mg for dust. (1,3)-β-d-glucan concentration ranged from 0.1 to 9.8 ng/m³ for air, and 6.6 to 110 ng/mg for dust. Cockroach allergens were detected only in New Haven office and outdoor environments, and other allergens ranged from 0.1 to 90 ng/mg for dust samples, and from 1.5 to 1,282 ng/m³ for air samples. In general, similar profiles of allergens and toxins were observed in New Haven and Nanjing environments. Linear regression analysis showed that there were better endotoxin and (1,3)-β-d-glucan linear correlations (R ² = 0.78, 0.87, respectively) between the dust and air samples compared to those of the allergens Der f 1 and Der p 1 (R ² = 0.5, 0.7, respectively). This research contributes to the development of robust biological exposure assessment and the elaboration of airborne and dust-borne bio-mass in the living environments.