Pollen production in olive cultivars and its interannual variability.

BACKGROUND AND AIMS: Olive (Olea europaea subsp. europaea var. europaea) is the most extensively cultivated fruit crop worldwide. It is considered a wind-pollinated and strictly outcrossing crop. Thus, elevated pollen production is crucial to guarantee optimum fruit set and yield. Despite these facts, the variability of pollen production within the cultivated olive has been scarcely studied. This study aimed to characterize this feature by analysing a representative set of worldwide olive cultivars. METHODS: We evaluated the average number of pollen grains per anther in 57 principal cultivars over three consecutive years. We applied a standard generalized linear model (GLM) approach to study the influence of cultivar, year and the previous year's fruit load on the amount of pollen per anther. Additionally, the K-means method was used for cluster analysis to group cultivars based on their pollen production capacity. KEY RESULTS: Pollen production per anther was highly variable among olive cultivars. The cultivar significantly accounted for 51.3 % of the variance in pollen production and the year for 0.3 %. The interaction between the two factors explained 8.4 % of the variance, indicating that not all cultivars were equally stable in producing pollen across the years. The previous year's fruit load and its interaction with the year were significant, but barely accounted for 1.5 % of the variance. Olive cultivars were classified into four clusters according to their capacity to produce pollen. Interestingly, the fourth cluster was composed of male-sterile cultivars, which presumably share this character by inheritance. CONCLUSIONS: Pollen production per anther varied extensively within the cultivated olive. This variation was mainly driven by the cultivar and its interaction with the year. The differential capacity of olive cultivars to produce pollen should be considered not only for designing new orchards but also gardens where this species is used as an ornamental.

A multidisciplinary approach of outdoor aeroallergen selection for Skin Prick Testing in the geographical area of Greater Istanbul.

SUMMARY: Background. Aeroallergen selection for skin prick testing and the interpretation of results need to be in line with allergenic sources of a specific geographic area. Objective. To identify aeroallergens for a skin test panel for the specific geographical area of Istanbul in a multidisciplinary approach based on aerobiological parameters, cross-reactivity patterns and clinical symptoms. Methods. Aerobiological parameters, cross reactivity patterns and the European Standard Skin Prick Test Panel determined allergen selection. Atopic adult patients (n = 60) compiled a questionnaire and were skin prick tested with 29 aeroallergens. Aerobiological sampling followed the requirements of the European Aerobiology Society. Results were statistically analyzed. Results. 65% of patients had positive skin reactions. Sensitization to at least one grass allergen was 30%. Key grass allergens were timothy grass (Phleum pratense L.) 25.8% and Johnson grass (Sorghum halepense (L.) Pers.) 22.6%; correlations between grass-sensitizations were significant at p (minor) 0.01 and so was the correlation of Pooideae sensitization with symptoms and medication. Sensitization to at least one woody plant was 23%; to ash (Fraxinus excelsior L.) 8.1%; hazelnut (Corylus avellana L.), olive (Olea europaea L.) and mulberry (Morus alba L.) 6.5%; juniper (Juniperus ashei J.Buchholz) 4.8%. Correlations between Fagales allergen sensitizations were significant. Sensitization to at least one weed was 22%, sensitization to dock (Rumex crispus L.) 12.9%, ragweed (Ambrosia artemisiifolia L.), and mugwort (Artemisia vulgaris L.) 4.8%. Sensitization rates correlated significantly with the length of the Main Pollen Season. Conclusions. The European Standard Panel is suitable for the geographical area of Greater Istanbul, if it comprises Johnson grass and ash. Ragweed has become clinically relevant in this region. Mulberry and dock were exclusively associated to polysensitized individuals suggesting pan-allergen involvement.

Methods for interpolating missing data in aerobiological databases.

Missing data is a common problem in scientific research. The availability of extensive environmental time series is usually laborious and difficult, and sometimes unexpected failures are not detected until samples are processed. Consequently, environmental databases frequently have some gaps with missing data in it. Applying an interpolation method before starting the data analysis can be a good solution in order to complete this missing information. Nevertheless, there are several different approaches whose accuracy should be considered and compared. In this study, data from 6 aerobiological sampling stations were used as an example of environmental data series to assess the accuracy of different interpolation methods. For that, observed daily pollen/spore concentration data series were randomly removed, interpolated by using different methods and then, compared with the observed data to measure the errors produced. Different periods, gap sizes, interpolation methods and bioaerosols were considered in order to check their influence in the interpolation accuracy. The moving mean interpolation method obtained the highest success rate as average. By using this method, a success rate of the 70% was obtained when the risk classes used in the alert systems of the pollen information platforms were taken into account. In general, errors were mostly greater when there were high oscillations in the concentrations of biotic particles during consecutive days. That is the reason why the pre-peak and peak periods showed the highest interpolation errors. The errors were also higher when gaps longer than 5 days were considered. So, for completing long periods of missing data, it would be advisable to test other methodological approaches. A new Variation Index based on the behaviour of the pollen/spore season (measurement of the variability of the concentrations every 2 consecutive days) was elaborated, which allows to estimate the potential error before the interpolation is applied.

Gain-switched semiconductor lasers with pulsed excitation and optical injection for dual-comb spectroscopy.

In this work we demonstrate the capability of two gain-switched optically injected semiconductor lasers to perform high-resolution dual-comb spectroscopy. The use of low duty cycle pulse trains to gain switch the lasers, combined with optical injection, allows us to obtain flat-topped optical frequency combs with 350 optical lines (within 10 dB) spaced by 100 MHz. These frequency combs significantly improve the spectral resolution reported so far on dual-comb spectroscopy with gain-switched laser diodes. We evaluate the performance of our system by measuring the transmission profile of an absorption line of H13CN at the C-band, analyzing the attainable signal-to-noise ratio for a range of averaging times.

A randomized trial comparing transanal irrigation and percutaneous tibial nerve stimulation in the management of low anterior resection syndrome.

AIM: To assess the effectiveness of transanal irrigation (TAI) compared with posterior tibial nerve stimulation (PTNS) in severe and chronic low anterior resection syndrome (LARS). METHOD: A two-group parallel, open-label randomized controlled trial carried out in a single university hospital. The study population included patients with a LARS scale score of more than 29 points who had undergone rectal surgery more than 1 year previously. These were randomly allocated, with a central randomization system, following a 1:1 sequence to TAI or PTNS. The main study outcome was to achieve a reduction of at least one LARS grade in at least 50% of the patients, for each intervention. RESULTS: A total of 27 patients (TAI = 13, PTNS = 14) were randomized. Both groups were similar with regard to confounding factors. Four patients were excluded because of intercurrent disease or early dropout, leaving 23 (TAI, n = 10; PTNS, n = 13) for analysis. Eight out of 10 and 4 out of 13 patients were downgraded with TAI and PTNS, respectively. The median LARS score decreased from 35 [interquartile range (IQR) 32-39] to 12 (IQR 12-26) (P = 0.021) for the TAI group and from 35 (IQR 34-37) to 30 (IQR 25-33) (P = 0.045) for the PTNS group. The Vaizey score fell from 15 (IQR 11-18) to 6 (IQR 4-7) (P = 0.037) and from 14 (IQR 13-17) to 9 (IQR 7-10) (P = 0.007) with TAI and PTNS, respectively, with 80% and 38% of patients, respectively, showing decreases of more than 50%. Improvement in quality of life was observed in both groups. CONCLUSION: Both treatments improved the LARS score in this study but this was only significant in the TAI group.

Spatio-temporal flowering patterns in Mediterranean Poaceae. A community study in SW Spain.

This study focused on phenological timing and spatial patterns in 30 Poaceae species flowering in spring in different types of plant cover (scrub, riverbank and pasture). Grass community composition was studied, and the influence of species and plant cover on the start date and duration of flowering was assessed from March to June in both 2014 and 2015. Twenty-nine sampling sites were selected for phenological monitoring using the BBCH scale. Data were subjected to GLMM analyses. Binary discriminant analysis revealed differences in grass community composition as a function of plant cover type; scrub cover comprised a considerably larger number of species than those in riverbank and pasture. Moreover, more species diversity was observed in 2014 than in 2015 with a drier and stressed pre-flowering period. Differences on phenology were also recorded between plant cover types and study years. Species in pasture and riverbank flowered before (113.4 days; 116.1 days) than species in scrub (120.9 days), being these species with shorter flowering length because they are more exposed to the characteristic of the Mediterranean region during the summer. In general, flowering onset occurred later in 2014 (118.2 days) than in 2015 (115.8 days), probably attributable to precipitation occurring during March. On the other hand, spatial autocorrelation within some cover types has been observed, showing spatial patterns exist at a smaller scale. The findings of this study contribute to a better understanding of grass phenology in different environments.

Defining pollen exposure times for clinical trials of allergen immunotherapy for pollen-induced rhinoconjunctivitis - an EAACI position paper.

BACKGROUND: Clinical efficacy of pollen allergen immunotherapy (AIT) has been broadly documented in randomized controlled trials. The underlying clinical endpoints are analysed in seasonal time periods predefined based on the background pollen concentration. However, any validated or generally accepted definition from academia or regulatory authorities for this relevant pollen exposure intensity or period of time (season) is currently not available. Therefore, this Task Force initiative of the European Academy of Allergy and Clinical Immunology (EAACI) aimed to propose definitions based on expert consensus. METHODS: A Task Force of the Immunotherapy and Aerobiology and Pollution Interest Groups of the EAACI reviewed the literature on pollen exposure in the context of defining relevant time intervals for evaluation of efficacy in AIT trials. Underlying principles in measuring pollen exposure and associated methodological problems and limitations were considered to achieve a consensus. RESULTS: The Task Force achieved a comprehensive position in defining pollen exposure times for different pollen types. Definitions are presented for 'pollen season', 'high pollen season' (or 'peak pollen period') and 'high pollen days'. CONCLUSION: This EAACI position paper provides definitions of pollen exposures for different pollen types for use in AIT trials. Their validity as standards remains to be tested in future studies.

Correlation between airborne Olea europaea pollen concentrations and levels of the major allergen Ole e 1 in Córdoba, Spain, 2012-2014.

Olea europaea L. pollen is the second-largest cause of pollinosis in the southern Iberian Peninsula. Airborne-pollen monitoring networks provide essential data on pollen dynamics over a given study area. Recent research, however, has shown that airborne pollen levels alone do not always provide a clear indicator of actual exposure to aeroallergens. This study sought to evaluate correlations between airborne concentrations of olive pollen and Ole e 1 allergen levels in Córdoba (southern Spain), in order to determine whether atmospheric pollen concentrations alone are sufficient to chart changes in hay fever symptoms. The influence of major weather-related variables on local airborne pollen and allergen levels was also examined. Monitoring was carried out from 2012 to 2014. Pollen sampling was performed using a Hirst-type sampler, following the protocol recommended by the Spanish Aerobiology Network. A multi-vial cyclone sampler was used to collect aeroallergens, and allergenic particles were quantified by ELISA assay. Significant positive correlations were found between daily airborne allergen levels and atmospheric pollen concentrations, although there were occasions when allergen was detected before and after the pollen season and in the absence of airborne pollen. The correlation between the two was irregular, and pollen potency displayed year-on-year variations and did not necessarily match pollen-season-intensity.

Analysis of profitability in the diagnosis of allergy to beta-lactam antibiotics.

UNLABELLED: Drug allergy is the third most common reason for allergy consultations. There is a tendency to call any adverse drug reaction (ADR) allergic, even without confirmatory allergy study. OBJECTIVES: (1) Evaluate time of resolution allergy to beta-lactam's study in a sample of 100 patients. (2) Analyse cost-effectiveness of current diagnostic study (skin tests, specific IgE and drug provocation test (DPT)). (3) Describe type and frequency of ADRs in adult/paediatric patients. (4) Compare cost of complete study with DPT. (5) Assess the need to restructure current study methodology according to results obtained. The study is part of a strategic plan of the allergy department (2005-2010). Patients with suspected allergy to beta-lactams were included. Procedures performed: medical history, specific IgE, skin tests and DPT. Cost/patient analysis. Cost of protocol analysis for current diagnostic/direct DPT. RESULTS: 100 patients were studied, 52 females/48 males; 43 children/57 adults. SYMPTOMS: 89 cutaneous, 4 anaphylaxis, 3 vasovagal reactions, 6 non-specific symptoms and 4 not recalled. Allergy was confirmed in six patients (only one child). Complete-study cost: 149.3 Euros/patient. DPT-study cost: 97.19 Euros/patient (34.9% less). Resolution time 9-13 months, absenteeism 28.04%. CONCLUSIONS: In the series studied, diagnosis of allergy to beta-lactams was confirmed in 6% of patients (2.3% of paediatric patients). After analysing results and cost of the study we believe that we should propose a specific diagnostic algorithm in those paediatric patients without suspected IgE-mediated ADR, and for those patients direct DPT should be conducted. This will reduce cost/patient (-34.9%), time of resolution and absenteeism.

Intention to prescribe self-injectable epinephrine: Are there differences depending on who assesses the patient post-reaction?

INTRODUCTION: Anaphylaxis is the most severe of all allergic reactions and can even prove fatal. There is limited evidence of a difference in prescribing patterns for self-injectable epinephrine (SIE) between general paediatricians and paediatricians with greater knowledge of allergology. OBJECTIVES: Assess knowledge about prescribing SIE of a sample of primary care/hospital paediatricians and paediatricians with specialised knowledge of allergology through a questionnaire asking them about clinical cases of anaphylaxis in their daily paediatric practice. MATERIALS AND METHODS: Participants were primary care and hospital paediatricians practicing in different regions of the province of Barcelona and paediatricians with specialised knowledge in the field of allergology from Spain. RESULTS: A total of 183 paediatricians responded. Of that 59.6% were paediatricians with specialised knowledge of allergology. General paediatricians in most cases correctly prescribed SIE device (more than 70% answered correctly in five of the eight clinical cases). In the case of drug anaphylaxis, which is an avoidable allergen for which SIE is not indicated, 67.5% of general paediatricians would prescribe it. In the case of exercise-induced anaphylaxis there were also differences in the prescription of epinephrine by general paediatricians, with only 40% prescribing it. CONCLUSIONS: In this study the percentage of SIE prescriptions would be higher than expected by general paediatricians, with no differences in the cases proposed between them and the paediatricians with better knowledge of allergology. Despite these results, it is important to insist on conducting education programmes and disseminating them to facilitate physicians' recognition and treatment of anaphylactic reactions.

Allergy medical care network: a new model of care for specialties.

UNLABELLED: In 2005 the Althaia Foundation Allergy Department performed its daily activity in the Hospital Sant Joan de Deu of Manresa. Given the increasing demand for allergy care, the department's performance was analysed and a strategic plan (SP) for 2005-2010 was designed. The main objective of the study was to assess the impact of the application of the SP on the department's operations and organisational level in terms of profitability, productivity and quality of care. MATERIAL AND METHODS: Descriptive, retrospective study which evaluated the operation of the allergy department. The baseline situation was analysed and the SP was designed. Indicators were set to perform a comparative analysis after application of the SP. RESULTS: The indicators showed an increase in medical care activity (first visits, 34%; successive visits, 29%; day hospital treatments, 51%), high rates of resolution, reduced waiting lists. Economic analysis indicated an increase in direct costs justified by increased activity and territory attended. Cost optimisation was explained by improved patient accessibility, minimised absenteeism in the workplace and improved cost per visit. CONCLUSIONS: After application of the SP a networking system was established for the allergy speciality that has expanded the territory for which it provides care, increased total activity and the ability to resolve patients, optimised human resources, improved quality of care and streamlined medical costs.

Cluster analysis of intradiurnal holm oak pollen cycles at peri-urban and rural sampling sites in southwestern Spain.

The impact of regional and local weather and of local topography on intradiurnal variations in airborne pollen levels was assessed by analysing bi-hourly holm oak (Quercus ilex subsp. ballota (Desf.) Samp.) pollen counts at two sampling stations located 40 km apart, in southwestern Spain (Cordoba city and El Cabril nature reserve) over the period 2010-2011. Pollen grains were captured using Hirst-type volumetric spore traps. Analysis of regional weather conditions was based on the computation of backward trajectories using the HYSPLIT model. Sampling days were selected on the basis of phenological data; rainy days were eliminated, as were days lying outside a given range of percentiles (P95-P5). Analysis of cycles for the study period, as a whole, revealed differences between sampling sites, with peak bi-hourly pollen counts at night in Cordoba and at midday in El Cabril. Differences were also noted in the influence of surface weather conditions (temperature, relative humidity and wind). Cluster analysis of diurnal holm oak pollen cycles revealed the existence of five clusters at each sampling site. Analysis of backward trajectories highlighted specific regional air-flow patterns associated with each site. Findings indicated the contribution of both nearby and distant pollen sources to diurnal cycles. The combined use of cluster analysis and meteorological analysis proved highly suitable for charting the impact of local weather conditions on airborne pollen-count patterns. This method, and the specific tools used here, could be used not only to study diurnal variations in counts for other pollen types and in other biogeographical settings, but also in a number of other research fields involving airborne particle transport modelling, e.g. radionuclide transport in emergency preparedness exercises.

A new method for determining the sources of airborne particles.

Air quality is a major issue for humans owing to the fact that the content of particles in the atmosphere has multiple implications for life quality, ecosystem dynamics and environment. Scientists are therefore particularly interested in discovering the origin of airborne particles. A new method has been developed to model the relationship between the emission surface and the total amount of airborne particles at a given distance, employing olive pollen and olive groves as examples. A third-degree polynomial relationship between the air particles at a particular point and the distance from the source was observed, signifying that the nearest area to a point is not that which is most correlated with its air features. This work allows the origin of airborne particles to be discovered and could be implemented in different disciplines related to atmospheric aerosol, thus providing a new approach with which to discover the dynamics of airborne particles.