Grass pollen is the major outdoor trigger of allergic respiratory diseases. Climate change is influencing pollen seasonality in Northern Hemisphere temperate regions, but many aspects of the effects ...on grass pollen remain unclear. Carbon dioxide and temperature rises could increase the distribution of subtropical grasses, however, medium term shifts in grass pollen in subtropical climates have not yet been analysed. This study investigates changes in grass pollen aerobiology in a subtropical city of Brisbane, Australia, between the two available monitoring periods, 1994-1999 and 2016-2020. Potential drivers of pollen change were examined including weather and satellite-derived vegetation indicators. The magnitude of the seasonal pollen index for grass showed almost a three-fold increase for 2016-2020 over 1994-1999. The number and proportion of high and extreme grass pollen days in the recent period increased compared to earlier monitoring. Statistically significant changes were also identified for distributions of CO
, satellite-derived seasonal vegetation health indices, and daily maximum temperatures, but not for minimum temperatures, daily rainfall, or seasonal fraction of green groundcover. Quarterly grass pollen levels were correlated with corresponding vegetation health indices, and with green groundcover fraction, suggesting that seasonal-scale plant health was higher in the latter period. The magnitude of grass pollen exposure in the subtropical region of Brisbane has increased markedly in the recent past, posing an increased environmental health threat. This study suggests the need for continuous pollen monitoring to track and respond to the possible effects of climate change on grass pollen loads.
Asthma epidemics associated with thunderstorms have had catastrophic effects on individuals and emergency services. Seasonal allergic rhinitis (SAR) is present in the vast majority of people who ...develop thunderstorm asthma (TA), but there is little evidence regarding risk factors for TA among the SAR population.
We sought to identify risk factors for a history of TA and hospital presentation in a cohort of individuals with SAR.
This multicenter study recruited adults from Melbourne, Australia, with a past diagnosis of TA and/or self-reported SAR. Clinical information, spirometry results, white blood cell count, ryegrass pollen–specific (RGP-sp) IgE concentration, and fractional exhaled nitric oxide were measured to identify risk factors for a history of TA in individuals with SAR.
From a total of 228 individuals with SAR, 35% (80 of 228) reported SAR only (the I-SAR group), 37% (84 of 228) reported TA symptoms but had not attended hospital for treatment (the O-TA group), and 28% (64 of 228) had presented to the hospital for TA (the H-TA group). All patients in the H-TA group reported a previous asthma diagnosis. Logistic regression analysis of factors associated with O-TA and H-TA indicated that lower FEV1 value and an Asthma Control Questionnaire score higher than 1.5 were associated with H-TA. Higher blood RGP-sp IgE concentration, eosinophil counts, and fractional exhaled nitric oxide level were significantly associated with both O-TA and H-TA. Receiver operating curve analysis showed an RGP-sp IgE concentration higher than 10.1 kU/L and a prebronchodilator FEV1 value of 90% or lower to be biomarkers of increased H-TA risk.
Clinical tests can identify risk of a history of TA in individuals with SAR and thereby inform patient-specific treatment recommendations.
While health services and their clinicians might seek to be innovative, finite budgets, increased demands on health services, and ineffective implementation strategies create challenges to sustaining ...innovation. These challenges can be addressed by building staff capacity to design cost-effective, evidence-based innovations, and selecting appropriate implementation strategies. A bespoke university award qualification and associated program of activities was developed to build the capacity of staff at Australia's largest health service to implement and evaluate evidence-based practice (EBP): a Graduate Certificate in Health Science majoring in Health Services Innovation. The aim of this study was to establish the health service's pre-program capacity to implement EBP and to identify preliminary changes in capacity that have occurred as a result of the Health Services Innovation program.
A mixed methods design underpinned by the Consolidated Framework for Implementation Research informed the research design, data collection, and analysis. Data about EBP implementation capacity aligned to the framework constructs were sought through qualitative interviews of university and health service executives, focus groups with students, and a quantitative survey of managers and students. The outcomes measured were knowledge of, attitudes towards, and use of EBP within the health service, as well as changes to practice which students identified had resulted from their participation in the program.
The Health Services Innovation program has contributed to short-term changes in health service capacity to implement EBP. Participating students have not only increased their individual skills and knowledge, but also changed their EPB culture and practice which has ignited and sustained health service innovations and improvements in the first 18 months of the program. Capacity changes observed across wider sections of the organization include an increase in connections and networks, use of a shared language, and use of robust implementation science methods such as stakeholder analyses.
This is a unique study that assessed data from all stakeholders: university and health service executives, students, and their managers. By assembling multiple perspectives, we identified that developing the social capital of the organization through delivering a full suite of capacity-building initiatives was critical to the preliminary success of the program.
Grass pollen is a major trigger for allergic rhinitis and asthma, yet little is known about the timing and levels of human exposure to airborne grass pollen across Australasian urban environments. ...The relationships between environmental aeroallergen exposure and allergic respiratory disease bridge the fields of ecology, aerobiology, geospatial science and public health.
The Australian Aerobiology Working Group comprised of experts in botany, palynology, biogeography, climate change science, plant genetics, biostatistics, ecology, pollen allergy, public and environmental health, and medicine, was established to systematically source, collate and analyse atmospheric pollen concentration data from 11 Australian and six New Zealand sites. Following two week-long workshops, post-workshop evaluations were conducted to reflect upon the utility of this analysis and synthesis approach to address complex multidisciplinary questions.
This Working Group described i) a biogeographically dependent variation in airborne pollen diversity, ii) a latitudinal gradient in the timing, duration and number of peaks of the grass pollen season, and iii) the emergence of new methodologies based on trans-disciplinary synthesis of aerobiology and remote sensing data. Challenges included resolving methodological variations between pollen monitoring sites and temporal variations in pollen datasets. Other challenges included “marrying” ecosystem and health sciences and reconciling divergent expert opinion. The Australian Aerobiology Working Group facilitated knowledge transfer between diverse scientific disciplines, mentored students and early career scientists, and provided an uninterrupted collaborative opportunity to focus on a unifying problem globally. The Working Group provided a platform to optimise the value of large existing ecological datasets that have importance for human respiratory health and ecosystems research. Compilation of current knowledge of Australasian pollen aerobiology is a critical first step towards the management of exposure to pollen in patients with allergic disease and provides a basis from which the future impacts of climate change on pollen distribution can be assessed and monitored.
•The Australian Aerobiology Working Group engaged in trans-disciplinary research.•The Group analysed available pollen count data sets from Australia and New Zealand.•The analysis revealed biogeographical diversity in airborne pollen types.•There were regional and seasonal variability in airborne grass pollen levels.•Pollen monitoring aids management of current and future patient exposure to grass pollen allergy triggers.
Liposome–protamine–DNA nanoparticles (LPD) are safe, effective, and non-toxic adjuvants that induce Th1-like immune responses. We hypothesized that encapsulation of allergens into liposomes could be ...an appropriate option for immunotherapy. The present study evaluated the immunotherapeutic potential of a recombinant hybrid molecule (rHM) encapsulated in LPD nanoparticles in a murine model of
Chenopodium album
allergy. BALB/c mice were sensitized with the allergen in alum, and the immunotherapy procedure was performed by subcutaneous injections of LPD-rHM, rHM, or empty LPD at weekly intervals. Sensitized mice developed a Th2-biased immune response characterized by strong specific IgG1 and IgE production, IL-4, and the transcription factor GATA3 in spleen cell cultures. Treatment with the LPD-rHM resulted in a reduction in IgE and a marked increase in IgG2a. The LPD-rHM induced allergen-specific responses with relatively high interferon-gamma production, as well as expression of the transcription factor T-bet in stimulated splenocytes. In addition, lymphoproliferative responses were higher in the LPD-rHM-treated mice than in the other groups. Removal of the nanoparticles from the rHM resulted in a decrease in the allergen’s immunogenicity. These results indicate that the rHM complexed with LPD nanoparticles has a marked suppressive effect on the allergic response and caused a shift toward a Th1 pathway.
Background
There is evidence that global anthropogenic climate change may be impacting floral phenology and the temporal and spatial characteristics of aero‐allergenic pollen. Given the extent of ...current and future climate uncertainty, there is a need to strengthen predictive pollen forecasts.
Methods
The study aims to use CatBoost (CB) and deep learning (DL) models for predicting the daily total pollen concentration up to 14 days in advance for 23 cities, covering all five continents. The model includes the projected environmental parameters, recent concentrations (1, 2 and 4 weeks), and the past environmental explanatory variables, and their future values.
Results
The best pollen forecasts include Mexico City (R2(DL_7) ≈ .7), and Santiago (R2(DL_7) ≈ .8) for the 7th forecast day, respectively; while the weakest pollen forecasts are made for Brisbane (R2(DL_7) ≈ .4) and Seoul (R2(DL_7) ≈ .1) for the 7th forecast day. The global order of the five most important environmental variables in determining the daily total pollen concentrations is, in decreasing order: the past daily total pollen concentration, future 2 m temperature, past 2 m temperature, past soil temperature in 28–100 cm depth, and past soil temperature in 0–7 cm depth. City‐related clusters of the most similar distribution of feature importance values of the environmental variables only slightly change on consecutive forecast days for Caxias do Sul, Cape Town, Brisbane, and Mexico City, while they often change for Sydney, Santiago, and Busan.
Conclusions
This new knowledge of the ecological relationships of the most remarkable variables importance for pollen forecast models according to clusters, cities and forecast days is important for developing and improving the accuracy of airborne pollen forecasts.
CatBoost is a preferable model for short‐term forecasts, while Deep Learning is for longer ones, but there is no definite answer to what the better model is for every day or city. Past pollen trends are strong indicators of future pollen concentrations. CatBoost can be used to determine the importance of environmental variables in forecasting daily total pollen concentration. Abbreviations: 2mT, 2 m temperature; CB, CatBoost; DL, Deep Learning; DOY, day of the year; ERA5, the fifth generation ECMWF (European Centre for Medium‐Range Weather Forecasts) atmospheric reanalysis dataset; pevap, potential evapotranspiration; st, soil temperature.
Grass pollens have been identified as mediators of respiratory distress, capable of exacerbating respiratory diseases including epidemic thunderstorm asthma (ETSA). It is hypothesised that during ...thunderstorms, grass pollen grains swell to absorb atmospheric water, rupture, and release internal protein content to the atmosphere. The inhalation of atmospheric grass pollen proteins results in deadly ETSA events. We sought to identify the underlying cellular mechanisms that may contribute towards the severity of ETSA in temperate climates using Timothy grass (
Phleum pratense
). Respiratory cells exposed to Timothy grass pollen protein extract (PPE) caused cells to undergo hypoxia ultimately triggering the subcellular re-organisation of F-actin from the peri junctional belt to cytoplasmic fibre assembly traversing the cell body. This change in actin configuration coincided with the spatial reorganisation of microtubules and importantly, decreased cell compressibility specifically at the cell centre. Further to this, we find that the pollen-induced reorganisation of the actin cytoskeleton prompting secretion of the pro-inflammatory cytokine, interleukin-8. In addition, the loss of peri-junctional actin following exposure to pollen proteins was accompanied by the release of epithelial transmembrane protein, E-cadherin from cell–cell junctions resulting in a decrease in epithelial barrier integrity. We demonstrate that Timothy grass pollen regulates F-actin dynamics and E-cadherin localisation in respiratory cells to mediate cell–cell junctional integrity highlighting a possible molecular pathway underpinning ETSA events.
Differences in grass pollen allergen exposure across Australia Beggs, Paul J.; Katelaris, Constance H.; Medek, Danielle ...
Australian and New Zealand journal of public health,
February 2015, 2015-02, 2015-Feb, 2015-02-00, 20150201, 2015-02-01, Letnik:
39, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Allergic rhinitis and allergic asthma are important chronic diseases posing serious public health issues in Australia with associated medical, economic, and societal burdens. Pollen are significant ...sources of clinically relevant outdoor aeroallergens, recognised as both a major trigger for, and cause of, allergic respiratory diseases. This study aimed to provide a national, and indeed international, perspective on the state of Australian pollen data using a large representative sample.
Atmospheric grass pollen concentration is examined over a number of years within the period 1995 to 2013 for Brisbane, Canberra, Darwin, Hobart, Melbourne, and Sydney, including determination of the ‘clinical’ grass pollen season and grass pollen peak.
The results of this study describe, for the first time, a striking spatial and temporal variability in grass pollen seasons in Australia, with important implications for clinicians and public health professionals, and the Australian grass pollen‐allergic community.
These results demonstrate that static pollen calendars are of limited utility and in some cases misleading. This study also highlights significant deficiencies and limitations in the existing Australian pollen monitoring and data.
Establishment of an Australian national pollen monitoring network would help facilitate advances in the clinical and public health management of the millions of Australians with asthma and allergic rhinitis.
To the Editor: Asthma prevalence in children has remained relatively constant in many Western countries, but hospital admissions for younger age groups have increased over time.1 Although the role of ...outdoor aeroallergens as triggers for asthma exacerbations requiring hospitalization in children and adolescents is complex, there is evidence that increasing concentrations of grass pollen are associated with an increased risk of asthma exacerbations in children.2 Human rhinovirus (HRV) infections are implicated in most of the serious asthma exacerbations in school-age children.3 In previous research, HRV infections and aeroallergen exposure have usually been studied independently. Furthermore, although sensitization to aeroallergens is an important risk factor for the development of asthma in children,5 little is known about the role of allergic sensitization to food and the risk of asthma admissions.6 The aims of this study were to assess the effect of outdoor grass pollen levels on the incidence of asthma admissions in children and to assess whether the presence of HRV and allergic sensitization modified this effect.
In November 2016, an unprecedented epidemic thunderstorm asthma event in Victoria, Australia, resulted in many thousands of people developing breathing difficulties in a very short period of time, ...including 10 deaths, and created extreme demand across the Victorian health services. To better prepare for future events, a pilot forecasting system for epidemic thunderstorm asthma (ETSA) risk has been developed for Victoria. The system uses a categorical risk-based approach, combining operational forecasting of gusty winds in severe thunderstorms with statistical forecasts of high ambient grass pollen concentrations, which together generate the risk of epidemic thunderstorm asthma. This pilot system provides the first routine daily epidemic thunderstorm asthma risk forecasting service in the world that covers a wide area, and integrates into the health, ambulance, and emergency management sector. Epidemic thunderstorm asthma events have historically occurred infrequently, and no event of similar magnitude has impacted the Victorian health system since. However, during the first three years of the pilot, 2017–19, two high asthma presentation events and four moderate asthma presentation events were identified from public hospital emergency department records. The ETSA risk forecasts showed skill in discriminating between days with and without health impacts. However, even with hindsight of the actual weather and airborne grass pollen conditions, some high asthma presentation events occurred in districts that were assessed as low risk for ETSA, reflecting the challenge of predicting this unusual phenomenon.
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