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Biomedical subjects

C Galán

Publications and source records attributed to C Galán.

At least 19 recordsLinked to original sources
PubMed2007

Detection of airborne allergen (Ole e 1) in relation to Olea europaea pollen in S Spain.

BACKGROUND: In recent years, it has been demonstrated that the air carries not only airborne pollen but also plant particles of smaller size that have allergenic activity, and, being within the respirable range, these particles can trigger rapid attacks in the lower respiratory tract. The study of particles according to size (0.7-40 micro m) could provide valuable information on the real allergenic activity in the atmosphere. OBJECTIVE: The purpose of this study was to analyse the dynamics of airborne Olea europaea pollen in contrast to the allergenic activity of Ole e 1 in the atmosphere. METHODS: The analyses were carried out with a Hirst-type volumetric collector and a cascade impactor simultaneously during the MPS of the olive. The indirect ELISA was used to detect the allergenic activity. The sampling was performed in Granada city centre (S Spain), in the Science Faculty building on the University of Granada from 30 April to 26 June 2005. RESULTS AND CONCLUSIONS: This research demonstrates that both the allergenic activity as well as the pollen particles follow in a similar curve, except in periods before or succeeding the main Olea pollen season. The study of the distribution of the allergenic particles according to their sizes reveals that the highest concentrations are between 3.3 and <0.7 micro m, thus indicating that allergenic activity primarily involves paucimicronic particles.

Air Pollutants↗
PubMed2006

Meteorological variation effect on aerobiology--new tools on pollen forecasting.

Spanish Aerobiology Network (REA) includes 22 research groups implied in the biological analysis of the air from 50 observation sites extended over the Iberian Peninsula and Baleares Islands. To offer in-advance information for pollen allergy sufferers, doctors and health authorities is one of REA priorities. One of our objectives is the study of the influence of meteorological variations on the quantity and occurrence of pollen in the atmosphere. Nevertheless, to include only weather parameters is not enough for build accurate forecasts. Field phenology data, vegetation land cover, topography data and previous aerobiological data should be included in the models. Meteorological conditions control the start, duration, intensity and end of the pollen season, but their effect depends on the different types of vegetation. The biological response of tree pollination is highly differentiated from the herbaceous one. Another important point is the adaptation of a given species phetnology to different climatic areas. We showed the different phenoclimatic variables determining tree flowering in the Mediterranean climate areas and in the Atlantic climate ones of the Iberian Peninsula, and the consequences on the development of our forecasting models. Finally we comment our more recent studies that use geostatistic algorithms as a tool for including all the cited parameters and also space variables as altitude, latitude and orientation to sun.

Algorithms↗
PubMed2004

Heat requirement for the onset of the Olea europaea L. pollen season in several sites in Andalusia and the effect of the expected future climate change.

Olives are one of the largest crops in the Mediterranean region, especially in Andalusia, in southern Spain. A thermal model has been developed for forecasting the start of the olive tree pollen season at five localities in Andalusia: Cordoba, Priego, Jaen, Granada and Malaga using airborne pollen and meteorological data from 1982 to 2001. Threshold temperatures varied between 5 degrees C and 12.5 degrees C depending on bio-geographical characteristics. The external validity of the results was tested using the data for the year 2002 as an independent variable and it confirmed the model's accuracy with only a few days difference from predicted values. All the localities had increasingly earlier start dates during the study period. This could confirm that olive flower phenology can be considered as a sensitive indicator of the effects of climate fluctuations in the Mediterranean area. The theoretical impact of the predicted climatic warming on the olive's flowering phenology at the end of the century is also proposed by applying Regional Climate Model data. A general advance, from 1 to 3 weeks could be expected, although this advance will be more pronounced in mid-altitude inland areas.

Climate↗
PubMed2004

Airborne plane-tree (Platanus hispanica) pollen distribution in the city of Córdoba, South-western Spain, and possible implications on pollen allergy.

Plane-trees are widely grown in Spain as ornaments. This taxon releases large amounts of pollen into the air and this pollen type seems to have proved implications on pollinosis. The aim of this study was to analyse airborne Platanus pollen content in the air of C6rdoba (South-western Spain) over the last 10 years, and its distribution in different areas of the city, as well as to consider possible implications regarding pollen allergies. Results revealed that Platanus pollen concentrations have been at their highest over the last 5 years. Within the city, the lowest pollen concentrations were in Northern areas of the city. Nevertheless, concentrations high enough to be of risk are reached over the whole city. All the patients studied presented symptoms during the Platanus pollen season. We can therefore conclude that plane pollen presents a risk for the whole city although symptoms are more intense and persistent in districts with a higher number of plane-trees. Platanus allergy is a particular problem for city-dwellers, where these trees are commonly used as ornamentals.

Adolescent↗
PubMed2004

Aerobiology as a tool to help in episodes of occupational allergy in work places.

Over 80% of weekday time is spent indoors and the air quality of this environment may affect the incidence of symptoms in allergy sufferers. However, indoor/outdoor measurements have been jointly considered only in a few studies. The objective of this paper is to analyse indoor/outdoor biological and non-biological particle content togeher with other factors affecting the severity of symptoms during working periods in an Aerobiology Lab during the most troublesome period of the year for allergy sufferers. For this purpose, indoor/ outdoor air samples were taken using standard portable particle traps at the National Coordinating Centre of the Spanish Aerobiology Network, University of Cordoba. The analysis differentiated between biological and non-biological material, and the allergy symptoms suffered by workers were quantified and correlated accordingly. An inventory of the incoming and outgoing sources of emissions was done in order to identify agravating co-factors. The results showed that since there was very little air movement between indoors and outdoors, there was a significant difference in the amount of biological material present in the two areas. The presence of some indoor source of emissions, such as the Plant Collections property of the Department, the Air Conditioned System and the volatile compounds of the copying machine was responsible of high particle content. External factors such as weather conditions or human activities contributed exacerbating symptoms. As Conclusion, the knowledge of airborne biological particle content could be a useful tool in minimising allergy symptoms when environmental conditions render them inevitable.

Adult↗
PubMed2003

Influence of meteorological parameters on Olea pollen concentrations in Córdoba (south-western Spain).

The influence of meteorological parameters on the dispersion of airborne pollen has been studied by several authors. Olive pollen is the major cause of allergy in southern Spain, where a large part of the arable surface area is given over to olive cultivation. Daily pollen forecasts provide important information both for pollen-allergy sufferers and for agronomists trying to achieve a better biological understanding of variations in airborne olive pollen levels. The main purpose of this paper is to study, by means of short-term statistical analysis, the effect of meteorological parameters on airborne olive pollen concentrations in the city of Cordoba (south-western Spain). Twenty-one-year (1982-2002) aerobiological and meteorological databases were used. Correlation and multiple regression analyses were used to study the relationships between olive pollen levels and several meteorological parameters. Statistical analysis was applied both to the whole pollen season and to the pre-peak period. Daily meteorological parameters, such as accumulated mean temperature, accumulated sunlight hours, and accumulated rainfall were used as independent variables in both statistical analyses. Accumulated meteorological variables were of the greatest value in most regression analysis equations, heat-related variables being the most important.

Forecasting↗
PubMed2002

Privet pollen (Ligustrum sp.) as potential cause of pollinosis in the city of Cordoba, south-west Spain.

BACKGROUND: Privet pollen rarely accounts for more than 1% of the annual total of daily pollen concentrations measured in a city; however in areas where these trees are widely used as ornamentals the amounts collected may be high enough to cause allergy symptoms. METHODS: Air samples taken with volumetric particle samplers Lanzoni VPPS 1000 (Lanzoni s.r.l., Bologna, Italy) show that there are differences in privet pollen concentrations measured in neighbourhoods with a high incidence of privet trees and in those taken at some distance from the source of emission. RESULTS: The results suggest that differences are due to the short dispersal range of the pollen grains once released from the plant, resulting from both the entomophilous nature of the plant and the large size of the pollen grains. Urban design, moreover, may play an important role in impeding pollen grain dispersion if the air cannot flow freely through long, narrow avenues. Another important consideration is that the last stages of the flowering period of privet overlaps with the flowering period of olive trees, the main allergen in the area. The fact that the two pollen types share common allergens means that there may be a cross-reaction between olive tree pollen and privet pollen. CONCLUSIONS: Privet pollen should be considered as a potential causative agent of local allergy problems in areas where its presence is extensive and is in combination with other allergens.

Air Pollutants↗
PubMed2001

The role of temperature in the onset of the Olea europaea L. pollen season in southwestern Spain.

Temperature is one of the main factors affecting the flowering of Mediterranean trees. In the case of Olea europaea L., a low-temperature period prior to bud development is essential to interrupt dormancy. After that, and once a base temperature is reached, the plant accumulates heat until flowering starts. Different methods of obtaining the best-forecast model for the onset date of the O. europaea pollen season, using temperature as the predictive parameter, are proposed in this paper. An 18-year pollen and climatic data series (1982-1999) from Cordoba (Spain) was used to perform the study. First a multiple-regression analysis using 15-day average temperatures from the period prior to flowering time was tested. Second, three heat-summation methods were used, determining the the quantities heat units (HU): accumulated daily mean temperature after deducting a threshold, growing degree-days (GDD): proposed by Snyder [J Agric Meteorol 35:353-358 (1985)] as a measure of physiological time, and accumulated maximum temperature. In the first two, the optimum base temperature selected for heat accumulation was 12.5 degrees C. The multiple-regression equation for 1999 gives a 7-day delay from the observed date. The most accurate results were obtained with the GDD method, with a difference of only 4.7 days between predicted and observed dates. The average heat accumulation expressed as GDD was 209.9 degrees C days. The HU method also gives good results, with no significant statistical differences between predictions and observations.

Allergens↗
PubMed2001

Model for forecasting Olea europaea L. airborne pollen in South-West Andalusia, Spain.

Data on predicted average and maximum airborne pollen concentrations and the dates on which these maximum values are expected are of undoubted value to allergists and allergy sufferers, as well as to agronomists. This paper reports on the development of predictive models for calculating total annual pollen output, on the basis of pollen and weather data compiled over the last 19 years (1982-2000) for Córdoba (Spain). Models were tested in order to predict the 2000 pollen season; in addition, and in view of the heavy rainfall recorded in spring 2000, the 1982-1998 data set was used to test the model for 1999. The results of the multiple regression analysis show that the variables exerting the greatest influence on the pollen index were rainfall in March and temperatures over the months prior to the flowering period. For prediction of maximum values and dates on which these values might be expected, the start of the pollen season was used as an additional independent variable. Temperature proved the best variable for this prediction. Results improved when the 5-day moving average was taken into account. Testing of the predictive model for 1999 and 2000 yielded fairly similar results. In both cases, the difference between expected and observed pollen data was no greater than 10%. However, significant differences were recorded between forecast and expected maximum and minimum values, owing to the influence of rainfall during the flowering period.

Allergens↗
PubMed2000

Meteorological factors affecting daily urticaceae pollen counts in southwest Spain.

The influence of meteorological factors on daily Urticaceae pollen counts were studied in Córdoba (southwest Spain) in 1996 and 1997. The daily Urticaceae pollen concentrations were obtained by using a Hirst-type volumetric sampler, and meteorological data were obtained from the Córdoba airport, located near the sampling site. The highest correlation between pollen concentration and meteorological parameters was obtained during non-rainy seasons. Temperature was found to be the most important meteorological parameter influencing pollen counts in spring, as temperature is the main reason for the increase of pollen concentration in the atmosphere. In autumn, humidity was another important parameter influencing pollen counts. Rain, however, did not appear to be significant. The influence of the pollen concentration of the 2 previous days and the pollen concentration of the previous day has been studied. During periods with low precipitation, the pollen concentration of the previous day was a useful predictor of Urticaceae pollen concentrations for the following day.

Climate↗
PubMed2000

Meteorological phenomena affecting the presence of solid particles suspended in the air during winter.

Winter is not traditionally considered to be a risky season for people who suffer from pollen allergies. However, increasing numbers of people are showing symptoms in winter. This prompted our investigation into the levels of solid material in the air, and some of the meteorological phenomena that allow their accumulation. This study showed a possible relationship between the phenomenon of thermal inversion, which occurs when very low temperatures, cloudless skies and atmospheric calms coincide, and an increase in the concentration of solid material in the atmosphere. Frequently, this situation is associated with other predictable phenomena such as fog, dew and frost. This may allow a warning system to be derived for urban pollution episodes. The effect caused by parameters such as wind and rainfall was also analysed. Solid material was differentiated into non-biological material from natural and non-natural sources (e.g. soot, dust, sand, diesel exhaust particles, partially burnt residues) and biological material. The latter mainly comprises pollen grains and fungal spores. Owing to its abundance and importance as a causal agent of winter allergies, Cupressaceae pollen was considered separately.

Air Pollutants↗
PubMed1989

Allergy to pollen grains from Amaranthaceae and Chenopodiaceae in Cordoba, Spain. Annual and daily variation of pollen concentration.

We have studied the annual and daily variation of pollen grains from Amaranthaceae and Chenopodiaceae for 3 consecutive years. Samples of pollen grains from both families, which make a stenopalynologic group, were collected by the volumetric method with the aid of a Burkard spore-trap. These pollen grains were found to occur in the atmosphere of the city of Córdoba virtually throughout the year, although their presence was continual only between April and October with maximum concentrations detected in the summer months. We have also studied the daily variation of pollen concentration, which peaked between 10 AM and 3 PM. In order to determine the incidence of pollinotic patients sensitive to pollen grains from Chenopodium, we reviewed 1000 clinical records available in the Allergy Unit and found 8.42% to be allergic. On evaluation of the time evolution of the symptoms we found that most patients continued to show them until September each year.

Air Pollution↗
PubMed1987

Occurrence of Alternaria Nees ex Fr. in indoor and outdoor habitats in Cordoba (Spain).

We have studied the occurrence of a genus of allergic interest, Alternaria, in the outdoor and indoor atmosphere of 14 homes in Córdoba (Spain). The sampling was carried out by the method of sedimentation on a mycological medium twice a month for a period of one year. We detected an overall 3955 colonies of Alternaria belonging to seven different species of this genus (A . consortiale, A . crassa, A . dendritica, A . harzii, A . japonica, A.tenuis and A . tenuissima), some of which are proven allergenic agents. A . tenuis was by far the most frequent of the above mentioned species, both indoors and outdoors. Three of the species identified (A . consortiale, A . crassa and A . harzii) occurred in greater concentrations indoors than outdoors; the remaining four were found to occur preferentially outdoors.

Air Microbiology↗
PubMedDate not supplied

Diurnal variation of airborne pollen at two different heights.

The diurnal variation in airborne pollen concentrations in the air of Córdoba at two different heights (1.5 m and 15 m) was studied during 2 consecutive years with the help of two Hirst volumetric samplers. According to pollen percentages obtained every hour, we determined whether every taxon studied presented a morning or an afternoon pattern, and whether this model was homogeneous (with a slight difference between the time of maximum and minimum reading) or heterogeneous (with a large difference between the two readings). We observed that the taxa that had many species in the area, such as Plantago, Poaceae, and Chenopodiaceae-Amaranthaceae showed a homogeneous model, while those taxa with few species present, such as Cupressaceae and Urticaceae showed a more heterogeneous model. Furthermore, the pattern of the plants with a large presence in the study area was more heterogeneous at 1.5 m because the pollen collected at this height is released from anthers. In the sampler placed at 15 m we detected airborne pollen, found that the curves were smoother and also observed a slight time delay for the taxa that were highly present in the area of study.

Altitude↗
PubMedDate not supplied

Effects of sampling height and climatic conditions in aerobiological studies.

This study examined the effect of sampling height on the measurement of airborne particles (pollen grains) common in the sampling area in the outskirts of the city of Córdoba, Spain. The effect of certain meteorological parameters on variations in concentration at different heights were also examined. The study was carried out throughout 1991 and 1992 using two Hirst samplers placed at two different heights (1.5 and 15 m) at the Faculty of Science at the University of Córdoba. The statistical results indicated that there were significant differences in the concentrations obtained at different heights, the values at 1.5 m being generally higher with the exception of pollen belonging to the Urticaceae family. The pollen counts of this type were greater at the higher elevation, probably due to the small size of the pollen, especially in the Urtica membranacea species, and to the convective phenomena in this climatic zone in spring, the season in which this species blooms. When these height comparison studies were conducted, the importance of the effect of placing the sampler in relation to a nearby building was also observed. Higher pollen concentrations were detected when the lower sampler was located on the leeward side. The meteorological parameters studied had some influence on the vertical dispersion of the pollen, although the percentage of variation according to height was very small, probably due to the short duration of the study. However, a certain relation between the differences in concentration per height and the degree of atmospheric stability was observed.

Air↗
PubMedDate not supplied

Allergenic pollen in the subdesert areas of the Iberian peninsula.

The yearly distribution of Artemisia and Chenopodiaceae-Amaranthaceae, two of the most common types of pollen in a rural area located in the southeastern part of the Iberian peninsula, was studied over a 3-year period (1995-1997). The particular bioclimatic conditions of the area, such as its subdesert climate, extreme dryness and high mountain location (1,000 m above sea level), have led to the adaptation and abundance of these species in this area. They usually flower in the second half of the year, and are the main pollen types collected in the samples in that time period. The Artemisia pollen levels recorded are the highest in Spain, since there are several species in the area which flower at different times. Chenopodiaceae-Amaranthaceae pollen counts are also very high. The severity of both pollen types was also analyzed. The height of the sampler was taken into account because the quantities at human height can be considerably higher than those recorded at 20 m off the ground. It was concluded that both pollen types should be considered some of the main causes of allergy in this area.

Air Pollution↗