Relación entre la variación horaria de la concentración de polen de Púmtago y la meteorología

XV lnternational A.P.L.E. Symposium of Palynolog

Conidios en la atmósfera de la ciudad de Mérida

XV lnternational A.P.L.E. Symposium of Palynolog

Semejanzas y diferencias entre dos estaciones aerobiológicas

XV lnternational A.P.L.E. Symposium of Palynolog

Arsenic species-binding proteins in human cardiovascular and muscle tissues

The intracellular As-protein binding in cytosol and methanol–water extract of the auricle and saphene tissues of As impacted people was evaluated by bidimensional size exclusion FPLC-UV-ICP-MS. The fractionation of cytosol using Superdex, Phenomenex and MonoQ HR 5/5 columns, shows that As was distributed in a wide range of contiguous fractions of each column, being 8, 25, 50 % the percentages of As in the collected fractions, respectively. Arsenic a sulphur coelute when FPLC–UV–ICP–MS was applied, which could implicate that As is bound to bio-compounds of different molecular mass through vicinal sulphur groups. The monitoring of S, Cu and P. In the methanol: water extracts a similar study than performed with the cytosol using preparative gel chromatography on Sephadex G-75 and Shephadex G-100 columns. A very low As and protein contain were found in the different fractions of both SEC fractionating series. A similar As–protein association to that found in the cytosol after fractionating with MonoQ HR 5/5 was observed for auricle and saphene. Inorganic and methylated As speciation in the 20 - 26 cytosol fractions obtained within the Phenomenex column was performed by HPLC–ICP–MS using the Hamilton PRP-X100 column. Only As(III) and As(V) were present and the results obtained shows that the As(III)/As(V) ratio is constant in most cases. Direct evidence of the existence of As–binding peptides in auricle and saphene vein from arsenic impacted human beings has have been obtained which was previously reported by means of novo peptide synthesis

Identificación y cuantificación del arsénico unido a las proteínas de tejidos cardiovasculares de pacientes sometidos a cirugía de revascularización coronaria

Introducción: Los efectos de la intoxicación con Arsénico (As) como enfermedades cardiovasculares (CV), pigmentaciones y oclusiones arteriales coronarias están asociados con la ingestión de As inorgánico a través del agua de bebida y a exposiciones ambientales. La unión del As (III) a proteínas y la metilación del As podría ser una primera etapa en el mecanismo de detoxificación. Objetivo: Evaluar la unión de As a proteínas en aurícula derecha y vena safena (VS) en sujetos expuestos de la Región de Antofagasta. Métodos: Se estudió la asociación As-proteína en el citosol de AD y VS de 6 pacientes con enfermedad coronaria grave de la Región de Antofagasta. Para el fraccionamiento del citosol se utilizaron columnas de exclusión molecular de tres diferentes rangos de masas. El perfil del As se detectó por Espectrometría de Masas Inductivamente Acoplado (ICP-MS) y por Espectroscopía Ultra Violeta - Visible de las fracciones moleculares (enlaces As- tiolatos de proteínas). Resultados: En todos los casos el As estuvo ampliamente distribuido en todo el intervalo de fracciones para AUD y VS. Los porcentajes de As colectado en las fracciones de las diferentes columnas usadas fueron 10, 25 y 50%. En la especiación de As en el citosol, por Cromatografía Líquida de Alta Resolución acoplada a la Espectrometría de Masas (IC-HPLC-ICP-MS), solamente se encontró As(III) y As(V) con una distribución Gaussiana para ambas especies, siendo la relación As(III)/As(V) constante para AUD y VS. Conclusión: En los tejidos CV existe asociación As – proteína lo cual podría implicar que el As está unido a biocompuestos de diferente peso molecular a través de grupos sulfhidrilos vecinales. Es probable que el As en AUD y VS se una a fracciones proteicas de masa molecular superior a 80 kDA y a subunidades de la estructura cuaternaria de la proteína nativa

Total and main as species present in cardiovascular tirrues of people living in as contaminated areas

The concentration levels of As in the Chilean II Region of Antofagasta produces non cancer health outcomes such as cardiovascular diseases and in last term heart attack. On this study, the determination of total As content and main inorganic and organoarsenic species found in three heart tissues (auricle, mammary artery and fat) and the saphene vein of people living in the Chilean II Region, suffering coronary thrombosis has been carried out. Comparison with similar tissues of patients from other non-contaminated areas has been undertaken. The extraction of As species occurred in methanol: water (1:1) and As species determination have been used the tandem HPLC-ICP-MS using the Hamilton PRP X100 anion column. For total As determination has been performed by HG-AAS and ICP-MS. The auricle and in less extend the saphene support the higher As concentration (mean values of 7.7 and 2.5 µg g-1, respectively), being As(III) the predominant species. Methylarsonate (MA) and dimethylarsinate (DMA) is not a favoured mechanism. The presence of high total As and high As(III) species content in the auricle and saphene of more contaminated people, the damage found in the saphene tissue and the global characteristics of the people under study in which the As stigmas are present in all of them, suggests that As could be involved in the cardiovascular diseases. e-mail: ipizarro @uantof.cl

Identification of potential sources of airborne 0lea pollen in the southwest Iberian Peninsula

Regional scale transport of olive pollen can result in increased nighttime concentrations of this important aeroallergen. This could be particularly important in Mediterranean countries where people can be outdoors during this time due to climate and lifestyle. Such studies are valuable for allergy sufferers and health care professionals because the information can be incorporated into forecasts, the outputs of which are used for avoiding exposure to aeroallergens and planning medication. The results of studies of this nature can also be used for examining gene flow in this important agricultural crop

Pattern and process in Amazon tree turnover, 1976-2001

Previous work has shown that tree turnover, tree biomass and large liana densities have increased in mature tropical forest plots in the late twentieth century. These results point to a concerted shift in forest ecological processes that may already be having significant impacts on terrestrial carbon stocks, fluxes and biodiversity. However, the findings have proved controversial, partly because a rather limited number of permanent plots have been monitored for rather short periods. The aim of this paper is to characterize regional-scale patterns of 'tree turnover' (the rate with which trees die and recruit into a population) by using improved datasets now available for Amazonia that span the past 25 years. Specifically, we assess whether concerted changes in turnover are occurring, and if so whether they are general throughout the Amazon or restricted to one region or environmental zone. In addition, we ask whether they are driven by changes in recruitment, mortality or both. We find that: (i) trees 10 cm or more in diameter recruit and die twice as fast on the richer soils of southern and western Amazonia than on the poorer soils of eastern and central Amazonia; (ii) turnover rates have increased throughout Amazonia over the past two decades; (iii) mortality and recruitment rates have both increased significantly in every region and environmental zone, with the exception of mortality in eastern Amazonia; (iv) recruitment rates have consistently exceeded mortality rates; (v) absolute increases in recruitment and mortality rates are greatest in western Amazonian sites; and (vi) mortality appears to be lagging recruitment at regional scales. These spatial patterns and temporal trends are not caused by obvious artefacts in the data or the analyses. The trends cannot be directly driven by a mortality driver (such as increased drought or fragmentation-related death) because the biomass in these forests has simultaneously increased. Our findings therefore indicate that long-acting and widespread environmental changes are stimulating the growth and productivity of Amazon forests

Observation of excited Lambda_b0 baryons

Using pp collision data corresponding to 1.0 fb-1 integrated luminosity collected by the LHCb detector, two narrow states are observed in the Lambda_b0pi+pi- spectrum with masses 5911.97 +- 0.12(stat) +- 0.02(syst) +- 0.66(Lambda_b0 mass) MeV/c^2 and 5919.77 +- 0.08(stat) +- 0.02(syst) +- 0.66(Lambda_b0 mass) MeV/c^2. The significances of the observations are 5.2 and 10.2 standard deviations, respectively. These states are interpreted as the orbitally-excited Lambda_b0 baryons, Lambda_b*0(5912) and Lambda_b*0(5920).Comment: Replaced by version published in Phys. Rev. Lett, modified fit with better mass resolution treatmen