Pollen Levels Research Articles

The association between environmental greenness and the risk of food allergy: A population-based study in Melbourne, Australia.

While exposure to environmental greenness in childhood has shown mixed associations with the development of allergic disease, the relationship with food allergy has not been explored. We investigated the association between exposure to environmental greenness and challenge-confirmed food allergy in a large population-based cohort. The HealthNuts study recruited 5276 12-month-old infants in Melbourne, Australia, who underwent skin prick testing to peanut, egg, and sesame; infants with a detectable wheal underwent food challenges to determine food allergy status. Environmental greenness was estimated using the normalized difference vegetation index (NDVI) for five buffer zones around the infant's home address: at the home, 100m, 500m, 800m, and 1600m radial distances. Environmental greenness was categorized into 3 tertiles and mixed effects logistic regression models quantified the association between greenness and the risk of food allergy, adjusting for confounding and accounting for clustering at the neighborhood level. NDVI data were available for n=5097. For most buffer zones, medium and high greenness, compared to low greenness, was associated with an increased risk of peanut allergy (eg, 100m tertile 2 aOR 1.89 95% CI 1.22-2.95, tertile 3 aOR 1.78 95% CI 1.13-2.82). For egg allergy, the effect sizes were smaller (100 m tertile 2 aOR 1.52 95% CI 1.16-1.97, tertile 3 aOR 1.38 95% CI 1.05-1.82). Socioeconomic status (SES) modified the association between greenness and peanut allergy, but not egg allergy; associations were apparent in the low SES group but not in the high SES group (p for interaction 0.08 at 100m). Air pollution (PM2.5) also modified the associations between environmental greenness and food allergy, with associations present in high air pollution areas but not low (p for interaction at 100m 0.05 for peanut and 0.06 for egg allergy.) CONCLUSION: Increased exposure to environmental greenness in the first year of life was associated with an increased risk of food allergy. Increased greenness may correlate with higher pollen levels which may trigger innate immune responses skewing the immune system to the Th2-dependent allergic phenotype; additionally, some pollen and food allergens are cross-reactive. Given the mixed data on greenness and other allergies, the relationship appears complex and may also be influenced by confounding variables outside those that were measured in this study.

Amplification of Local Mulberry Pollen by Import to Southern Ontario

White Mulberrry (Morus alba) is invasive throughout Midwest, Central and Eastern USA extending into adjoining areas of Canada. Red Mulberry, a native of the Carolinian forest, is rarely found. Morus alba was introduced from Asia in colonial times to establish a silkworm industry. Mulberry cultivars have also become popular for ornamentals in urban settings. Mulberry is, by far, usually the most prevalent type of pollen in our area, whereas the preponderance of Mulberry trees is far less than pollen levels suggest.

Indoor Pollen Concentrations of Mountain Cedar (Juniperus ashei) during Rainy Episodes in Austin, Texas.

Standard pollen monitoring programs evaluate outdoor pollen concentrations; however, information on indoor pollen is crucial for human wellbeing as people spend most of the day in indoor environments. In this study, we investigated the differences in indoor mountain cedar pollen loads between rooms of different uses and with different ventilation at The University of Texas in Austin and focused on the effect of rainy episodes on indoor/outdoor ratios of pollen concentrations. Pollen were sampled outdoors and indoors, specifically in seven rooms and in two thermal labs with controlled ventilation, during the daytime on 6 days in 2015. We calculated daily pollen concentrations, campaign pollen integrals (CPIn, the sum of all daily pollen concentrations) and ratios between indoor and outdoor concentrations (I/O ratio). Pollen concentrations differed substantially based on features related to room use and ventilation: Whereas the highest CPIn was observed in a room characterized by a frequently opened window and door, the smallest CPIn was related to a storeroom without any windows and no forced ventilation. Our results showed that rainy episodes were linked to a higher mean I/O ratio (0.98; non-rainy episodes: 0.05). This suggests that pollen accumulated indoors and reached higher levels than outdoors. Low ratios seem to signal a low level of risk for allergic people when staying inside. However, under very high outdoor pollen concentrations, small ratios can still be associated with high indoor pollen levels. In turn, high I/O ratios are not necessarily related to a (very) high indoor exposure. Therefore, I/O ratios should be considered along with pollen concentration values for a proper risk assessment. Exposure may be higher in indoor environments during prevailing precipitation events and at the end of the pollen season of a specific species. Standardized indoor environments (e.g., thermal labs) should be included in pollen monitoring programs.

Effect of the addition of bee pollen to the diet on performance, eggshell quality and serum parameters in layer quails

This study was carried out to determine the effect of bee pollen addition to quail diets on performance, eggshell quality and serum biochemical properties. In the experiment, 120 quails aged 70 days were randomly distributed to 6 treatment groups with 4 replicates. The quails were fed for 10 weeks with 6 trial diets with 0, 2, 4, 6, 8 and 10 g/kg bee pollen added. The body weight change, egg production, egg weight, egg mass, feed conversion ratio, damaged eggs, eggshell weight, eggshell thickness and serum glucose, creatinine, albumin, globulin and total protein levels of quails were not affected by the addition of bee pollen to the diet (P>0.05). The addition of 10 g/kg bee pollen to the diet significantly decreased feed intake compared to the control group (0 g/kg). Eggshell breaking strength was decreased by adding bee pollen to the diet and the lowest value was observed at the group fed the diet containing 6 g/kg bee pollen.Serum cholesterol concentration was minimized when 10 g/kg bee pollen was added to the diet(P<0.05). In addition, serum calcium and phosphorus contents were increased compared to the control (0 g/kg) group and these parameters reached the maximum at the 10 g/kg bee pollen level (P<0.01).According to the results of the experiment, the addition of bee pollen to the diet had a positive effect on serum cholesterol, calcium and phosphorus levels in layer quails, however, it had a negative effect on eggshell breaking strength.

Data mining assessment of Poaceae pollen influencing factors and its environmental implications

Poaceae pollen is highly allergenic, with a marked contribution to the pollen worldwide allergy prevalence. Pollen counts are defined by the species present in the considered area, although year-to-year oscillations may be triggered by different parameters, among which are weather conditions. Due to the predominant role of Poaceae pollen in the allergenicity in urban green areas, the aim of this study was the analysis of pollen trends and the influence of meteorology to forecast relevant variations in airborne pollen levels. The study was carried out during the 1993–2020 period in Ourense, in NW Iberian Peninsula. We used a volumetric Lanzoni VPPS 2000 trap for recording Poaceae airborne pollen grains, and meteorological daily data were obtained from the Galician Institute for Meteorology and Oceanography. The main indexes of the pollen season and their trends were calculated. A correlation analysis and ‘C5.0 Decision Trees and Rule-Based Models’ data mining algorithm were applied to determine the influence of meteorological conditions on pollen levels. We detected atmospheric Poaceae pollen during 139 days on average, mainly from April to August. The mean pollen grains amount recorded during the pollen season was 4608 pollen grains, with the pollen maximum peak of 276 pollen/m3 on 27 June. We found no statistically significant trends and slight slopes for the seasonal indexes, similarly to previous Poaceae studies in the same region. The calculated C5.0 model offered defined results, indicating that the combination of mean temperature above 17.46 °C and sunlight exposure higher than 12.7 h is conductive to significantly high pollen levels. The obtained results make possible the identification of risk moments during the pollen season for the activation of protective measures for sensitized population to grass pollen.

Changes of pollen viability after preservation of Paeonia lactiflora in different provenances

Pollen contains all the haploid genetic information of species and is of great significance to preserve germplasm resources safely and effectively. The acquisition of high quality materials is a very important step in germplasm preservation. This study compared the viability and physiological condition of Paeonia lactiflora pollen from several provenances after preservation, to explore the effect of provenance difference on pollen viability and physiological responses after preservation. The results showed that: the pollen viability of two cultivars were significantly different in provenances after preserved at −20 °C or liquid nitrogen (LN) for 3 months, the pollen viability of ‘Fen Yu Nu’ showed Lanzhou > Beijing > Luoyang > Heze, while the pollen viability of ‘Zi Feng Chao Yang’ showed Luoyang > Beijing > Heze. Similarly, the oxidative stress levels of the Paeonia lactiflora pollen after preservation with LN or −20 °C were also significantly different among the provenances, and there was a relationship between the viability and the oxidative stress levels produced by the provenances differences. Reactive oxygen species (ROS) content, malondialdehyde (MDA) content, superoxide dismutase (SOD) activity and glutamate reductase (GR) activity in pollen from different provenances were contrary to the changes of viability; while catalase (CAT), ascorbic acid peroxidase (APX), ascorbic acid (AsA) and glutathione (GSH) were consistent with the changes of viability. The results indicated that the responses of antioxidant systems of two cultivars pollen to preservation with LN or −20 °C were different in provenances, and this difference was one of the reasons for the different viability of pollen after preservation with LN or −20 °C.

Assessing pollen extreme events over a Mediterranean site: Role of local surface meteorology

The presence of very high pollen levels in the atmosphere is associated with a strong impact on health and a worsening of symptoms in people who already have a respiratory disease. However, there is no specification on the aerobiological, environmental and meteorological factors that allow for characterizing a pollen event as of great magnitude due to the significant impact it can cause on the population and the environment. This work proposes criteria to typify the levels of atmospheric pollen as an extreme pollen event (EPE), and aims to determine the meteorological variables that can affect the presence and permanence of high pollen concentrations over a period of time. To address this goal, the quasi-climatological pollen dataset recorded in Granada (Southeastern Spain) during the period 1992–2019, has been used. On the daily accumulated pollen concentrations, the 95th, 97th and 99th percentiles were calculated. Spearman's correlation between the pollen concentration exceeding the proposed thresholds (C > P95, C > P97, C > P99) and surface meteorological variables recorded during up to five days before the event were established in order to identify the meteorological conditions that might affect the EPEs. As for the number of days with values higher than the established percentiles, it has been seen that in the case of total pollen and Olea, Cupressaceae and Pinus, there is a robust monotonically ascending trend throughout the study period. Regarding meteorological variables, relative humidity and 24-h accumulated precipitation are shown as the two most influential variables up to three days before the event, although temperatures, visibility and wind direction also show a correlation with some pollen types. The criteria proposed in this work allow us for classifying high levels of pollen as an EPE, and lay the foundations of these extreme events in a context of climate change in which they will become more frequent.

Climate change and allergy-related impacts on humans

Abstract Climate change represents a massive threat to global health that could affect many disease factors in the twenty-first century. The influence of a changing climate on allergic disease has generated interest among the public and the scientific community. Climate change is a continuing process that affects allergy, and there are multiple potential consequences of climatic change on plant phenology. Impacts on pollen may be one of the most important consequences of climate change on human health. A growing number of people are contracting allergic diseases caused by pollen. Airborne pollen is one of the common causatives and triggering agents of respiratory allergy in a changing climate. Moreover, allergenic plants grow in soil disturbed by human activities and deforestation with air pollution, and it is impossible to avoid plants that cause allergies because pollen can travel many kilometers on the wind. Weather conditions may alter pollen concentrations. A number of studies have shown that increased CO 2 concentration and atmospheric temperature increase pollen concentration. Hence, most works on the impact of climate change on aeroallergens include its impact on the amount and allergenicity of pollen. It is as yet unknown what complex interactions between pollens, meteorological variables and air pollutants occur as a result of climate change. Considering the effect of climate change on long-term trends in pollen levels and emerging viral infections, it is crucial to report and forecast the associated risk for future human health.

Pollen Allergy in a Changing Planetary Environment.

Airborne pollens are one of the common causative and triggering agents of respiratory allergy in a changing planetary environment. A growing number of people worldwide are contracting allergic diseases caused by pollens. The seasonal variations in pollens have occurred everywhere and the sensitization rate to pollens has increased in children as well as in adults. Moreover, allergenic plants, such as ragweed and Japanese hop, grow in soil damaged by human’s activities and deforestation with air pollution. It is impossible to avoid plants that cause allergies, because pollens can travel many kilometers in the breeze or wind. Hence, it is essential to survey and forecast pollens for the management of pollen allergy. Weather conditions may alter pollen concentrations. A number of studies have shown that increases in CO2 concentration and atmospheric temperature raise pollen concentration. Hence most of the studies on the impact of climate change on aeroallergens must include the amount and allergenicity of pollens. It is yet unknown whether complex interactions with pollens, meteorological variables, and air pollutants in the changing environment. Considering the effect of climate change on the long-term trends in pollen levels and emerging viral infection, it is crucial to forecast and eliminate the associated risk for human health in future and take appropriate measures to reduce it.

A Study on Antiallergic Agents Prescribed to Patients with Japanese Cedar Pollinosis at an ENT Clinic in Omura City in Nagasaki Prefecture in 2016 and 2019

I conducted a detailed examination of the prescription rates of antiallergic agents, including oral and nasal preparations, prescribed for patients with Japanese cedar pollinosis in 2016, when there was little cedar pollen in the air, and in 2019, when the atmospheric levels of cedar pollen were much higher.

Data Mining Methods to Detect Airborne Pollen of Spring Flowering Arboreal Taxa

Variations in the airborne pollen load are among the current and expected impacts on plant pollination driven by climate change. Due to the potential risk for pollen-allergy sufferers, this study aimed to analyze the trends of the three most abundant spring-tree pollen types, Pinus, Platanus and Quercus, and to evaluate the possible influence of meteorological conditions. An aerobiological study was performed during the 1993–2020 period in the Ourense city (NW Spain) by means of a Hirst-type volumetric sampler. Meteorological data were obtained from the ‘Ourense’ meteorological station of METEOGALICIA. We found statistically significant trends for the Total Pollen in all cases. The positive slope values indicated an increase in pollen grains over the pollen season along the studied years, ranging from an increase of 107 to 442 pollen grains. The resulting C5.0 Decision Trees and Rule-Based Models coincided with the Spearman’s correlations since both statistical analyses showed a strong and positive influence of temperature and sunlight on pollen release and dispersal, as well as a negative influence of rainfall due to washout processes. Specifically, we found that slight rainfall and moderate temperatures promote the presence of Pinus pollen in the atmosphere and a marked effect of the daily thermal amplitude on the presence of high Platanus pollen levels. The percentage of successful predictions of the C5.0 models ranged between 62.23–74.28%. The analysis of long-term datasets of pollen and meteorological information provides valuable models that can be used as an indicator of potential allergy risk in the short term by feeding the obtained models with weather prognostics.

Within city spatiotemporal variation of pollen concentration in the city of Toronto, Canada

BackgroundThe exacerbation of asthma and respiratory allergies has been associated with exposure to aeroallergens such as pollen. Within an urban area, tree cover, level of urbanization, atmospheric conditions, and the number of source plants can influence spatiotemporal variations in outdoor pollen concentrations. ObjectiveWe analyze weekly pollen measurements made between March and October 2018 over 17 sites in Toronto, Canada. The main goals are: to estimate the concentration of different types of pollen across the season; estimate the association, if any, between pollen concentration and environmental variables, and provide a spatiotemporal surface of concentration of different types of pollen across the weeks in the studied period. MethodsWe propose an extension of the land-use regression model to account for the temporal variation of pollen levels and the high number of measurements equal to zero. Inference is performed under the Bayesian framework, and uncertainty of predicted values is naturally obtained through the posterior predictive distribution. ResultsTree pollen was positively associated with commercial areas and tree cover, and negatively associated with grass cover. Both grass and weed pollen were positively associated with industrial areas and TC brightness and negatively associated with the northing coordinate. The total pollen was associated with a combination of these environmental factors. Predicted surfaces of pollen concentration are shown at some sampled weeks for all pollen types. SignificanceThe predicted surfaces obtained here can help future epidemiological studies to find possible associations between pollen levels and some health outcome like respiratory allergies at different locations within the study area.

Influence of high temperature on viability of winter rapeseed polen in vitro conditions

Flowering Brassica napus at high temperatures leads to a negative impact on the generative organs of plants, reducing the viability and fertility of pollen, changes in the hormonal background. There is an acceleration of embryo development and, as a result, that significantly increases the level of abortion of embryos, decreases the level of auxin and increases the defects of embryos, worsens the germination of pollen tubes in vitro and in vivo. There is the development of seedless pods, inhibition of seed development and as a consequence, reduced yields. Influencing pollen of different varieties and hybrids by temperature stressors, analyzing its fertility and sterility, the presence of abnormal, defective pollen grains, and their number the length of pollen tubes, the ability of pollen to germinate under both in vivo and in vitro conditions allows to select from the population resistant to this factor genotypes for use in breeding studies The aim of our research was to study the viability of winter rape pollen under the conditions of treatment with high temperature pollen in a nutrient medium. The research was conducted at the Institute of Oilseeds Crops of NAAS. Four varieties and one sample of winter rapeseed of foreign selection were taken for the experiment. Pollen and anthers in the experiment were exposed to the higt temperature of 32 ± 1ºC, in the control variants pollen and anthers not exposed to the stressor. The inhibitory effect of the factor was evaluated by the degree of reduction of pollen viability in experimental variants compared with controls. In the control variants for all tested varieties large differences in the percentage of pollen germination were not observed, the minimum was in the variety Pronto - 41.1%, the maximum in the variety Tenor - 50.5%. Experimental variants for this indicator also differed little from each other. The maximum percentage of pollen germination in the experiment was for the variety Jan - 15.0%, the minimum for the variety K571 - 11.4%. The differences between the control and experimental variants in 4 varieties and the sample were significant. According to the degree of reduction of pollen viability in experimental variants in comparison with control all provided varieties and samples differed, the greatest degree of decrease of 76.3% was noted for Tenor variety, what is the evidence of low resistance of its pollen to high temperature, the smallest degree of reduction of this indicator - 32, 5% was noted for the sample K571, which is an indicator of the highest stability at the pollen level compared to other varieties tested. In the experiment on anther heating, the viability of pollen of all varieties and samples did not differ significantly from similar indicators of the previous experiment. The lowest percentage of pollen germination was observed in the Cornet variety - 0.3, the highest in the Pronto variety - 3.2, respectively. The degree of reduction in the percentage of pollen germination in the experimental variants compared to the control was high in all varieties tested, the differences between this indicator in the control and experimental variants were significan Thus, according to the obtained results germination of pollen in a nutrient medium at high temperatures led to a decrease in its viability. Taking into account the degree of reduction of this indicator in the experimental variants in comparison with the control, all varieties were classified according to resistance to high temperatures. The Tenor variety had the largest and the K571 variety the smallest degree of decline and were characterized by us as correspondingly unstable and resistant to high temperatures at the level of microgametophyte. Heating of anthers led to a significant reduction in pollen viability. All varieties tested had a high degree of reduction of this indicator in the experimental variants in comparison with the control and were characterized by us as unstable to high temperatures at the pollen level. The influence of high temperatures on pollen compared to the germination of pollen in a nutrient medium under the same conditions suppressed the viability of pollen to a much greater extent.

Palaeoenvironmental conditions and human activity in the vicinity of the Grodzisko fortified settlement (central Europe, Poland) from the late‐Neolithic to the Roman period

AbstractWe present results from a palaeoecological analysis conducted on deposits accumulated in an oxbow lake of the Prosna River (Poland), next to the Grodzisko fortified settlement. Palaeobotanical and geochemical analyses—supported by radiocarbon dating—were performed to (i) reconstruct palaeoenvironmental conditions of the oxbow lake and its surrounding area; (ii) determine the beginning of the human activity in the fortified settlement vicinity; and (iii) assess the impact of human pressure on the environment. The Grodzisko fortified settlement was originally located on a river island, encircled by a wetland, improving its defensive value. Increases in the water level (1800–1300 BC and 700–200 BC) created a small lake/moat around the fortified settlement. Indicators for human activity from pollen records suggest the presence of human populations from the late Neolithic, ca. 2800 BC, with a clear intensification ca. 1700 BC. From ca. 1600 BC, a decrease in some decidous trees suggests forest clearance. Low levels of human activity indicator pollen ca. 2000 BC suggest a reduction of human pressure (possible depopulation). The regular presence of macrocharcoal pieces and an increase in human activity indicator pollen from ca. 1300 to 200 BC provide evidence for renewed human habitation around the sampling site.

Potential contribution of distant sources to airborne Betula pollen levels in Northeastern Iberian Peninsula

Betula (birch) pollen is one of the most important causes of respiratory allergy in Northern and Central Europe. While birch trees are abundant in Central, Northern, and Eastern Europe, they are scarce in the Mediterranean territories, especially in the Iberian Peninsula (IP), where they grow only in the northern regions and as ornamental trees in urban areas. However, the airborne birch pollen patterns in Catalonia (Northeastern IP) show abrupt high concentrations in areas with usually low local influence. The intensity of the derived health problems can be increased by outbreaks due to long-range pollen transport. The present work evaluates the different potential contributions to Catalonia from the main source regions: Pyrenees, Cantabria, and the forests of France and Central Europe. To this end, we computed the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) back trajectories of air masses associated with the main Betula pollen peaks occurring simultaneously over different Catalan monitoring stations, and we studied their provenance over a 15-year period. The Vielha aerobiological station on the northern slopes of the Central Pyrenees was used to identify the dates of the pollen season in the Pyrenean region. In order to better understand the role of the Pyrenees, which is the nearest of the four birch forested regions, we classified the pollen peaks in the other Catalan stations into three groups based on the relationship between the peak and the pollen season in the Pyrenees. Our analysis of back-trajectory residence time, combined with the associated pollen concentration, reveals that two principal routes other than the Pyrenean forest sustain the northerly fluxes that enter Catalonia and carry significant concentrations of Betula pollen. This study has also allowed quantifying the differentiated contributions of the potential source regions. In addition, the Weather Research Forecast (WRF) mesoscale model has been used to study three specific episodes. Both models, HYSPLIT and WRF, complement each other and have allowed for better understanding of the main mechanisms governing the entry of birch pollen to the region.

Investigation of the Nutritional and Quality Properties of Meatballs Added with Bee Pollen and Apigenin

Objective: The present study was carried out to investigate the possibility of using different levels of bee pollen and apigenin extract in beef meatballs to evaluate shelf-life, nutritional and quality properties of beef meatball under different storage conditions.
 
 Materials and Methods: It was determined, using the HPLC method, that bee pollen contains a high level of apigenin under optimal conditions. Bee pollen and apigenin were added to meatballs at different concentrations in five groups. Meatballs were made with control, 1-2% bee pollens/apigenin. Quality and safety evaluation of meatballs were determined by sensory, physicochemical, biochemical and microbiological tests. The analyses were conducted at 1st, 3th, 7th and 14th days of interval. 
 
 Results: A statistically significant decrease was found in FFA, POV and TBARS levels of meatballs on different days of storage (p

Lower pollen nutritional quality delays nest building and egg laying in Bombus terrestris audax micro-colonies leading to reduced biomass gain

The performance of Bombus terrestris micro-colonies fed five diets differing in pollen species composition and level of nine essential amino acids (EAA; leucine, lysine, valine, arginine, isoleucine, phenylalanine, threonine, histidine, methionine) was assessed for 37 days by recording total biomass gain, nest building initiation, brood production (eggs, small and large larvae, pupae, drones), nectar, and pollen collection. Stronger colony performance was linked to higher amino acid levels but no consistent differences in biomass gain were recorded between mono- and poly-species diets. Poorest performance occurred in micro-colonies offered pure oilseed rape (OSR) pollen which contained the lowest EAA levels. Reduced micro-colony development (delayed nest initiation and lower brood production) was related to OSR proportion in the diet and lower EAA levels. Results are discussed in relation to selection of plant species in the design of habitats to promote bee populations.

Белок профилин как клинически значимый паналлерген в развитии синдрома пыльцевой и пищевой аллергии

Профилин играет важную роль в качестве сенсибилизатора и фактора, представляющего трудности как в диагностике, так и в лечении пациентов с пыльцевой и растительной пищевой аллергией. В контролируемых исследованиях профилин доказал свою способность вызывать различные симптомы заболеваний верхних и нижних дыхательных путей. До конца не изучено клиническое значение профилинов в развитии респираторных заболеваний в реальных условиях воздействия, и в какой степени это способствует появлению симптомов. Крупные эпидемиологические исследования показали, что профилин является маркером тяжести заболевания и полисенсибилизации при аллергии на травы, а сенсибилизация к rPhl p 12 статистически связана с большей длительностью заболевания и оральным аллергическим синдромом к растительной пище. Роль профилина в развитии орального аллергического синдрома на растительные продукты питания была признана у пациентов с аллергией на пыльцу. Кроме того, профилин может вызывать системные реакции на растительную пищу в отдельных группах населения, которые обычно сталкиваются с сезонами с высоким уровнем пыльцы травы. Несмотря на то, что профилин считается второстепенным аллергеном, он является основным аллергеном некоторых растительных продуктов, например дыни (Cuc m 2), апельсина и сои. Аллергия на дыню, арбуз, цитрусовые, помидоры и бананы, как сообщается, является клиническим маркером гиперчувствительности к профилину. Его значение у лиц с аллергией на латекс остается низким или он вообще не имеет значения согласно некоторым публикациям. Невзирая на вышеупомянутую актуальность, не существует надежного терапевтического подхода к лечению аллергии на белок профилин. Более того, у пациентов с сенсибилизацией к профилину аллерген-специфическая иммунотерапия не показана ввиду недостаточного количества минорных компонентов в препаратах для данного вида терапии, а пищевая иммунотерапия недостаточно изучена. Таким образом, профилактические стратегии, а именно элиминационные мероприятия и симптоматическая терапия, могут быть оптимальным вариантом лечения для пациентов, чувствительных к профилину.

550Short-term exposure to grass pollen is associated with lower lung function and increased airway inflammation

Abstract Background The association between grass pollen exposure and lung function changes and airway inflammation is limited. We investigated these associations in a community-based sample, and whether any such associations were modified by current asthma, current hay fever, pollen sensitization and age. Methods Cross-sectional analyses of data from the Melbourne Atopy Cohort Study (MACS) participants (n = 936). Lung function was assessed using spirometry. Airway inflammation was assessed by fractional exhaled nitric oxide (FeNO), and exhaled breath condensate pH and nitrogen oxides (NOx). Daily pollen counts were collected using a volumetric spore trap. The associations were examined by linear regression. Results Higher ambient levels of grass pollen 2 days before (lag 2) were associated with lower mid-forced expiratory flow (FEF25-75%) and FEV1/FVC ratio (Coef. [95% CI] = -119 [-226, -11] mL/s and -1.0 [-3.0, -0.03] %, respectively) and also 3 days before (lag 3). Increased levels of grass pollen a day before (lag 1) was associated with increased FeNO (4.35 [-0.1, 8.7] ppb) and also at lag 2. Adverse associations between pollen and multiple outcomes were greater in adults with current asthma, hay fever and pollen sensitization. Conclusions Grass pollen exposure was associated with eosinophilic airway inflammation 1-2 days after exposure and airway obstruction 2-3 days after exposure. Key messages There is a more delayed effect on lung function compared to airway inflammation. Adults with current asthma, hay fever and grass pollen sensitisation are especially vulnerable.

1250Grass pollen exposure and children’s asthma repeat admissions in Victoria, Australia

Abstract Background Paediatric asthma-related readmissions significantly challenge public health systems. As evidence suggests readmissions are possibly associated with ambient grass pollen levels, we sought to determine the relationship between grass pollen exposure and the risk of readmission for asthma among children in Victoria, Australia. Methods The Victorian Admitted Episodes Dataset 1st July 1997–30th June 2009 was used to identify primary admissions with a principal diagnosis of asthma for children aged 2-18 years. Total sample size was 48,068 admissions. Readmissions were defined as a subsequent admission within 28 days of index discharge. Multiple semi-parametric Poisson Generalized Additive Models were used to assess associations between the grass pollen season and daily grass pollen counts (lagged and cumulative) with repeat admissions, while controlling for meteorological factors and air pollutants. Results Readmissions totalled to 2,152 (4.47% of all admissions). Mean daily readmissions were 1.44 times higher during the grass pollen season (95%CI 1.03-2.02). Pollen season was associated with readmission only for the youngest age group (2-5), incident rate ratio 1.99 (95%CI 1.26-3.14). Daily readmission was non-linearly associated with same day pollen counts only for the 13-18-year age group. Lag 2 pollen counts were non-linearly associated with all daily readmissions for boys in gender-stratified and younger age groups (2-5, 6-12) in age-stratified analysis. Conclusions Grass pollen exposure was associated with higher readmission rates for paediatric asthma. Key messages Younger children and boys with severe or poorly controlled asthma need to be assessed for preventive therapies before the grass pollen season to reduce the repeat admissions.