Browsing by Subject "Pollen"

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    Artemisia pollen is the main vector for airborne endotoxin
    (Elsevier, 2018-08-09) Oteros, José; Bartusel, Elke; Alessandrini, Francesca; Núñez, Andrés; Moreno, Diego A.; Behrendt, Heidrun; Schmidt-Weber, Carsten; Traidl-Hoffmann, Claudia; Buters, Jeroen; Genética y Microbiología
    Background: Endotoxin (LPS) released from gram-negative bacteria causes strong immunologic and inflammatory effects and, when airborne, can contribute to respiratory conditions, such as allergic asthma. Objectives: We sought to identify the source of airborne endotoxin and the effect of this endotoxin on allergic sensitization. Methods: We determined LPS levels in outdoor air on a daily basis for 4 consecutive years in Munich (Germany) and Davos (Switzerland). Air was sampled as particulate matter (PM) greater than 10 μm (PM > 10) and PM between 2.5 and 10 μm. LPS levels were determined by using the recombinant Factor C assay. Results: More than 60% of the annual endotoxin exposure was detected in the PM > 10 fraction, showing that bacteria do not aerosolize as independent units or aggregates but adhered to large particles. In Munich 70% of annual exposure was detected between June 12th and August 28th. Multivariate modeling showed that endotoxin levels could be explained by phenological parameters (ie, plant growth). Indeed, days with high airborne endotoxin levels correlated well with the amount of Artemisia pollen in the air. Pollen collected from plants across Europe (100 locations) showed that the highest levels of endotoxin were detected on Artemisia vulgaris (mugwort) pollen, with little on other pollen. Microbiome analysis showed that LPS concentrations on mugwort pollen were related to the presence of Pseudomonas species and Pantoea species communities. In a mouse model of allergic disease, the presence of LPS on mugwort pollen was needed for allergic sensitization. Conclusions: The majority of airborne endotoxin stems from bacteria dispersed with pollen of only one plant: mugwort. This LPS was essential for inducing inflammation of the lung and allergic sensitization.
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    Assessment and statistical modelling of airborne microorganisms in Madrid
    (Elsevier, 2020-11-21) Cordero, José María; Núñez, Andrés; García, Ana M.; Borge, Rafael; Genética y Microbiología
    The limited evidence available suggests that the interaction between chemical pollutants and biological particles may intensify respiratory diseases caused by air pollution in urban areas. Unlike air pollutants, which are routinely measured, records of biotic component are scarce. While pollen concentrations are daily surveyed in most cities, data related to airborne bacteria or fungi are not usually available. This work presents the first effort to understand atmospheric pollution integrating both biotic and abiotic agents, trying to identify relationships among the Proteobacteria, Actinobacteria and Ascomycota phyla with palynological, meteorological and air quality variables using all biological historical records available in the Madrid Greater Region. The tools employed involve statistical hypothesis contrast tests such as Kruskal-Wallis and machine learning algorithms. A cluster analysis was performed to analyse which abiotic variables were able to separate the biotic variables into groups. Significant relationships were found for temperature and relative humidity. In addition, the relative abundance of the biological phyla studied was affected by PM10 and O3 ambient concentration. Preliminary Generalized Additive Models (GAMs) to predict the biotic relative abundances based on these atmospheric variables were developed. The results (r = 0.70) were acceptable taking into account the scarcity of the available data. These models can be used as an indication of the biotic composition when no measurements are available. They are also a good starting point to continue working in the development of more accurate models and to investigate causal relationships.
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    Clave determinativa genérica de pólenes tricolpados
    (Murcia: Universidad de Murcia, Servicio de Publicaciones, 1986) Baño Breis, Francisco del; Facultad de Biología
    A dichotomic key for the identification of one hundred of genera and families of tricolpate pollen is proposed. The generic key is accesible through an entry key which selects the main types of pollinic sculptures and refers to the corresponding groups. In the preliminary sections of the entry key. the principal types of exin are described. Some general reflexions on pollinic morphology are given.
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    Comprehensive analysis of different adhesives in aerobiological sampling using optical microscopy and high-throughput DNA sequencing
    (Elsevier, 2019-04-05) Rojo, Jesús; Núñez, Andrés; Lara, Beatriz; Sánchez-Parra, Beatriz; Moreno, Diego A.; Pérez-Badía, Rosa; Genética y Microbiología
    The standardization and unification of the procedures to analyze and quantify the airborne pollen concentrations are very important topics. In this work, the effectiveness of the two most used adhesives in aerobiological sampling, silicone prepared with cyclohexane solvent (Silicone) and petroleum jelly (Vaseline), was compared under outdoor conditions. This comparison was carried out using the traditional method based on the identification and quantification by optical microscopy (OM) of the airborne pollen and the novel methodology by high-throughput sequencing analysis (HTS). Globally, the results from both methods of analysis (OM and HTS) showed a good agreement between the two adhesives tested regarding the abundance of the main pollen types present in the samples: Cupressaceae, Olea, Poaceae, Platanus, Quercus. We concluded that the results from both adhesives are comparable data. Furthermore, the comparisons between methodologies, OM vs. HTS, showed that both techniques can accurately identify the most abundant pollen types in the atmosphere for the studied periods, with a good agreement of their relative abundances especially when the airborne pollen diversity is low but showing some divergences as the number of pollen types increases.
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    Evaluation of Stryphnodendron polyphyllum (Mart.) pollen as antioxidant and antibacterial potential
    (Universidad de Murcia. Servicio de publicaciones, 2023) Nogueira Oliveira Albuquerque, Rafael; Gomes Martins, Carlos Henrique; de Souza, Jonathan Henrique; de Melo Sacramento, Verônica; Alves de Oliveira, Dario; Farias de Melo-Júnior, Afrânio; Veiga Menezes, Elytania; Fernandes Souza, Luciano; de Andrade Royo, Vanessa
    El polen de Stryphnodendron polyphyllum, conocido como barbatimão, es un problema para los apicultores con apiarios cerca de la planta, por la toxicidad para las abejas. El objetivo fue evaluar la actividad antioxidante, antibacteriana y determinar fenoles totales y taninos en el extracto etanólico. La actividad antioxidante se evaluó por método DPPH. La actividad antibacteriana por método de microdilución. Los taninos totales y fenoles se determinaron por método espectrofotométrico. Se identificó actividad inhibitoria y bactericida para E. coli, P. aeruginosa, S. mutans, S. sobrinus, S. sanguinis, S. salivarius y L. paracasei. Se determinó EC50 de 7.42- mg/mL en la actividad antioxidante. Para compuestos fenólicos y tánicos, por comparación con curva de calibración, 3,12±0,005g/ 100g de muestra como ácido gálico y 7,3±0,03g/100g como ácido tánico. Se realizó cromatografía líquida de alta resolución para obtener el perfil cromatográfico.
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    Sedimentación y distribución superficial de palinomorfos en cuevas del se ibérico. Implicaciones en paleoecología
    (Murcia: Universidad de Murcia, Servicio de Publicaciones, 2001) Navarro Camacho, Cristina; Munuera Giner, Manuel; Prieto, A. R.; Carrión García, José Sebastián; Facultad de Biología
    Se ha realizado un análisis polínico del sedimento superficial de varias cavidades kársticas de la España mediterránea con el fin de conocer los procesos tafonómicos que afectan al polen en este contexto sedimentario. Los resultados confirman el potencial paleoecológico de los depósitos de cuevas. Los espectros polínicos reflejan la vegetación que crece en los alrededores de la cueva, así como, parcialmente, la vegetación regional. La distribución, deposición y preservación polínicas no son homogéneas en el interior de las cuevas, estando influenciadas por la morfología de la cueva y diversos procesos estocásticos. La aridez se confirma como un factor positivo para la preservación polínica y, por tanto, resulta una garantía en estudios de reconstrucción paleoambiental.
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    Temporal patterns of variability for prokaryotic and eukaryotic diversity in the urban air of Madrid (Spain)
    (Elsevier, 2019-09-10) Núñez, Andrés; Amo de Paz, Guillermo; Rastrojo, Alberto; Ferencova, Zuzana; Gutiérrez-Bustillo, A. Montserrat; Alcamí, Antonio; Moreno, Diego A.; Guantes, Raúl; Genética y Microbiología
    Although many microorganisms are ubiquitously present in the air, airborne microbial communities have been much less characterized than those in soil or aquatic environments. Besides its ecological importance, detection and monitoring of the wide diversity of these aerosolized microorganisms (bacteria, viruses, fungi and pollen) is relevant for understanding allergy and disease outbreaks, especially in highly populated cities. In this study, we describe the simultaneous biodiversity of bacteria, fungi and plants present in the urban atmosphere of Madrid (Spain) along different seasonal periods, using DNA sequencing. Sampling in two different locations (downtown and peri-urban) we found that changes in the composition of each community are mainly driven by environmental factors, rather than by the features of the specific sampling microenvironments. While pollen particles are dominated by a few taxa characteristic of each season, bacteria and fungi show a high diversity but stable core communities along the year. The prokaryotic core is governed by soil and leaf surface bacteria, with predominance of Actinobacteria (Frankiales and Micrococcales) and Alphaproteobacteria (Sphingomonadales, Rhodobacterales, Rhizobiales and Acetobacterales). Fungal diversity is characterized by the steady presence of members of Capnodiales and Pleosporales. Pathogenic bacterial and fungal taxa were also detected across the year. We also correlated the airborne biodiversity with environmental variables. Air temperature has a strong influence on the community composition of bacteria, while pollen and fungi seasonal variations are mainly correlated with precipitation. Our results contribute to the characterization of airborne prokaryotic and eukaryotic communities in urban areas and show the suitability of this method for biosurveillance strategies.
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    The differential vertical distribution of the airborne biological particles reveals an atmospheric reservoir of microbial pathogens and aeroallergens
    (Springer, 2020-03-27) Núñez, Andrés; Moreno, Diego A.; Genética y Microbiología
    The most abundant biological particles present in the air are bacteria, fungal propagules and pollen grains. Many of them are proved allergens or even responsible for airborne infectious diseases, which supports the increase of studies in recent years on their composition, diversity, and factors involved in their variability. However, most studies in urban areas are conducted close to ground level and a factor such as height is rarely taken into account. Thus, the information about how the composition of biological particles changes with this variable is scarce. Here, we examined the differential distribution of bacteria, fungi, and plants at four altitudes (up to ∼ 250 m) in a metropolitan area using high-throughput DNA sequencing. Most taxa were present at all levels (common taxa). However, a transitional layer between 80 and 150 m seemed to affect the scattering of these bioaerosols. Taxa not present at all altitudes (non-common) showed an upward tendency of diversity for bacteria and plants with height, while the opposite trend was observed for fungi. Certain patterns were observed for fungi and specific plant genera, while bacterial taxa showed a more arbitrary distribution and no patterns were found. We detected a wide variety of aeroallergens and potential pathogens at all heights, which summed a substantial portion of the total abundance for fungi and plants. We also identified potential connections between the biological particles based on their abundances across the vertical section.