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1.
Crit Rev Food Sci Nutr ; 62(29): 8230-8246, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34036844

RESUMEN

According to the European Union regulation, some countries have established a pre-market notification system for food supplements while others have not. As this regulation is unfulfilled, a notified and marketed food supplement ingredient in one country may be forbidden in another. Even though food supplements shall not be placed on the market if unsafe, some products may still expose the consumers to risks. The risk is increased by easier access due to worldwide dissemination fostered by the internet and free movement of goods in the European Union. The Rapid Alert System for Food and Feed and the Emerging Risks Exchange Network are described. To date, the European Union legislation does not include a provision to establish a dedicated vigilance system for food supplements (Nutrivigilance). Six European Union countries have nevertheless set up national systems, which are presented. The present lack of European Union data collection harmonization, does not allow easy cooperation between countries. This article advocates for creating a coordinated European Nutrivigilance System to detect and scrutinize adverse effects of food supplements. This, to help in directing science-based risk assessments and reinforce the science-based decision of policy makers to improve public health safety.


Asunto(s)
Seguridad de Productos para el Consumidor , Salud Pública , Suplementos Dietéticos/efectos adversos , Unión Europea , Legislación Alimentaria
2.
Nature ; 437(7058): 529-33, 2005 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-16177786

RESUMEN

Future climate warming is expected to enhance plant growth in temperate ecosystems and to increase carbon sequestration. But although severe regional heatwaves may become more frequent in a changing climate, their impact on terrestrial carbon cycling is unclear. Here we report measurements of ecosystem carbon dioxide fluxes, remotely sensed radiation absorbed by plants, and country-level crop yields taken during the European heatwave in 2003. We use a terrestrial biosphere simulation model to assess continental-scale changes in primary productivity during 2003, and their consequences for the net carbon balance. We estimate a 30 per cent reduction in gross primary productivity over Europe, which resulted in a strong anomalous net source of carbon dioxide (0.5 Pg C yr(-1)) to the atmosphere and reversed the effect of four years of net ecosystem carbon sequestration. Our results suggest that productivity reduction in eastern and western Europe can be explained by rainfall deficit and extreme summer heat, respectively. We also find that ecosystem respiration decreased together with gross primary productivity, rather than accelerating with the temperature rise. Model results, corroborated by historical records of crop yields, suggest that such a reduction in Europe's primary productivity is unprecedented during the last century. An increase in future drought events could turn temperate ecosystems into carbon sources, contributing to positive carbon-climate feedbacks already anticipated in the tropics and at high latitudes.


Asunto(s)
Dióxido de Carbono/metabolismo , Productos Agrícolas/metabolismo , Desastres , Ecosistema , Efecto Invernadero , Calor , Atmósfera/química , Carbono/metabolismo , Europa (Continente) , Lluvia , Factores de Tiempo
3.
Environ Pollut ; 150(1): 125-39, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17604887

RESUMEN

Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N(2) fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N(2)O, NO and bi-directional NH(3) exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols.


Asunto(s)
Contaminantes Atmosféricos/química , Efecto Invernadero , Modelos Químicos , Compuestos de Nitrógeno/química , Contaminantes Atmosféricos/análisis , Atmósfera , Ecosistema , Monitoreo del Ambiente/métodos , Europa (Continente) , Compuestos de Nitrógeno/análisis
4.
Cancer Lett ; 120(1): 79-85, 1997 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-9570389

RESUMEN

We studied whether the cultivated mushroom (Agaricus bisporus) or 4-(carboxy)phenylhydrazine (CP) induce lung adenomas in the A/J mouse lung tumor model. For 26 weeks female mice were fed a semisynthetic diet where 11 or 22% of the diet was replaced by freeze-dried mushrooms. The intake of the mushroom diets was equivalent to an intake of agaritine, the major phenylhydrazine derivative occurring in the mushroom, of 92 or 166 mg/kg body weight per day. The intake of CP was 106 mg/kg body weight per day. Neither the freeze-dried mushroom nor CP induced statistically significant increased numbers of lung adenomas in female A/J mice in the administered dosages.


Asunto(s)
Adenoma/inducido químicamente , Neoplasias Pulmonares/inducido químicamente , Fenilhidrazinas , Agaricus , Animales , Femenino , Ratones , Ratones Endogámicos A
5.
In Vivo ; 7(4): 325-30, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8218974

RESUMEN

The toxicological and neurotoxicological effects of 2-propanol were investigated in a 12-week study in male rats. 2-propanol was administered in drinking water in concentrations of 0, 1, 2, 3 and 5% (w/v). Autopsy and histopathological examinations of liver, heart, spleen, testes, kidneys and adrenals were performed. The content of glial fibrillary acidic protein (GFAP) was measured semiquantitatively by a densitometric method applied to immunohistochemically stained sections from the dorsal hippocampus. The relative organ weights of liver, kidneys and adrenals were statistically significantly increased in a dose-dependent manner. No histopathological alterations could be attributed to the dosing, apart from a dose-dependent increase in formation of hyaline casts and droplets in the proximal tubules of the kidneys. 2-propanol does not seem to cause astrogliosis after 12 weeks of dosing.


Asunto(s)
1-Propanol/toxicidad , Proteína Ácida Fibrilar de la Glía/análisis , Hipocampo/efectos de los fármacos , 1-Propanol/administración & dosificación , Animales , Densitometría , Hipocampo/química , Masculino , Ratas , Ratas Endogámicas , Factores de Tiempo
6.
Environ Pollut ; 109(3): 423-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15092875

RESUMEN

Patterns of ozone concentration ([O(3)]), O(3) deposition velocity (v(d)) and O(3) flux (F(c)) over an evergreen forest canopy are shown in relation to measuring method, physiological activity of the trees, and time of year. The gradient and eddy correlation methods were compared and showed similar diel v(d) patterns. Daytime F(c) was correlated with CO(2) and water vapour fluxes, while no correlation between [O(3)] in the range 10-70 ppb (nl l(-1)) and F(c) was seen in this study. F(c) was primarily driven by stomatal conductance, reactions with surfaces, particles and gases, and not by [O(3)]. On a monthly basis, [O(3)] was always highest in the afternoon while v(d) was typically higher in the morning, resulting in an equal F(c) over the day. Night-time F(c) was more than half of the daytime O(3) flux. The data reveal the importance of emissions of nitric oxide and terpenes as O(3) removal factors in evergreen forest dominated by Norway spruce.

7.
Environ Pollut ; 184: 201-10, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24060739

RESUMEN

Tropospheric O3 is a strong oxidant that may affect vegetation and human health. Here we report on the O3 fluxes from a poplar plantation in Belgium during one year. Surprisingly, the winter and autumn O3 fluxes were of similar magnitude to ones observed during most of the peak vegetation development. Largest O3 uptakes were recorded at the beginning of the growing season in correspondence to a minimum stomatal uptake. Wind speed was the most important control and explained 44% of the variability in the nighttime O3 fluxes, suggesting that turbulent mixing and the mechanical destruction of O3 played a substantial role in the O3 fluxes. The stomatal O3 uptake accounted for a seasonal average of 59% of the total O3 uptake. Multiple regression and partial correlation analyses showed that net ecosystem exchange was not affected by the stomatal O3 uptake.


Asunto(s)
Contaminantes Atmosféricos/análisis , Ozono/análisis , Populus/fisiología , Agricultura , Contaminación del Aire/estadística & datos numéricos , Bélgica , Ecosistema , Monitoreo del Ambiente , Agricultura Forestal , Humanos , Estaciones del Año , Viento
8.
Eur J Clin Nutr ; 64 Suppl 3: S108-11, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21045838

RESUMEN

This paper presents the plant information included in the eBASIS (BioActive Substances in Foods Information System) database on composition and biological activity of selected bioactive compounds from European plant/mushroom foods with putative beneficial and/or toxic effects. The European Food Information Resource (EuroFIR)-NETTOX Plant List (2007) presents scientific and vernacular names in 15 European languages for around 325 major European plant/mushroom foods and also for different parts of these foods. This list and its predecessor, the NETTOX List of Food Plants, have been used by national food authorities and within the European Union for consideration of plants and mushrooms that have been used to a significant degree up to 1997 and are therefore not covered by the novel food regulation (European Parliament and Council of the European Union, 1997). The species and the plant part studied are insufficiently characterised in many scientific papers. This paper informs about the naming of plants and mushrooms as an aid for scientists who are not botanists or mycologists themselves. Knowledge on scientific names used, including synonyms, may also be important for finding all relevant papers when searching the literature. In many cases, vernacular/trivial names in, for example, English do not uniquely identify the species. Finally, recommendations are given to assist researchers and reviewers of papers dealing with botanical/mycological information.


Asunto(s)
Agaricales/clasificación , Plantas Comestibles/clasificación , Terminología como Asunto , Bases de Datos Factuales
9.
Vet Parasitol ; 167(1): 55-61, 2010 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-19850412

RESUMEN

Fecal analyses are becoming increasingly important for equine establishments as a means of parasite surveillance and detection of anthelmintic resistance. Although several studies have evaluated various egg counting techniques, little is known about the quantitative effects of pre-analytic factors such as collection and storage of fecal samples. This study evaluated the effects of storage temperature, storage time and airtight versus open-air storage on fecal egg counts. The experimental protocols were replicated in two study locations: Copenhagen, Denmark and Athens, Georgia, USA. In both locations, the experiment was repeated three times, and five repeated egg counts were performed at each time point of analysis. In experiment A, feces were collected rectally and stored airtight at freezer (-10 to -18 degrees C), refrigerator (4 degrees C), room (18-24 degrees C), or incubator (37-38 degrees C) temperatures. Egg counts were performed after 0, 6, 12, 24, 48, and 120h of storage. In experiment B, feces were collected rectally and stored airtight or in the open air in the horse barn for up to 24h. Egg counts were performed after 0, 3, 6, 12, and 24h of storage. In experiment A at both locations, samples kept in the refrigerator showed no decline in egg counts, whereas storage in the freezer and incubator led to significantly declining egg numbers during the study. In contrast, storage at room temperature yielded marked differences between the two study locations: egg counts remained stable in the U.S. study, whereas the Danish study revealed a significant decline after 24h. In experiment B, the Danish study showed no differences between airtight and open-air storage and no changes over time, while the U.S. study found a significant decline for open-air storage after 12h. This difference was attributed to the different barn temperatures in the two studies. To our knowledge, this is the first study to evaluate the pre-analytic factors affecting egg counts in horses using an experimental protocol replicated in two contrasting geographic and climatic locations. Our results demonstrate that refrigeration is the best method for storage of fecal samples intended for egg count analysis, but that accurate results can be derived from fecal samples collected from the ground within 12h of passage.


Asunto(s)
Heces/parasitología , Enfermedades de los Caballos/parasitología , Recuento de Huevos de Parásitos/veterinaria , Manejo de Especímenes/veterinaria , Infecciones por Strongylida/veterinaria , Estrongílidos/crecimiento & desarrollo , Animales , Clima , Dinamarca , Georgia , Enfermedades de los Caballos/diagnóstico , Caballos , Análisis de los Mínimos Cuadrados , Recuento de Huevos de Parásitos/métodos , Recuento de Huevos de Parásitos/normas , Manejo de Especímenes/métodos , Manejo de Especímenes/normas , Infecciones por Strongylida/diagnóstico , Infecciones por Strongylida/parasitología , Temperatura , Factores de Tiempo
10.
Int J Biometeorol ; 49(6): 377-87, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15688192

RESUMEN

We tested the hypothesis that the date of the onset of net carbon uptake by temperate deciduous forest canopies corresponds with the time when the mean daily soil temperature equals the mean annual air temperature. The hypothesis was tested using over 30 site-years of data from 12 field sites where CO(2) exchange is being measured continuously with the eddy covariance method. The sites spanned the geographic range of Europe, North America and Asia and spanned a climate space of 16 degrees C in mean annual temperature. The tested phenology rule was robust and worked well over a 75 day range of the initiation of carbon uptake, starting as early as day 88 near Ione, California to as late as day 147 near Takayama, Japan. Overall, we observed that 64% of variance in the timing when net carbon uptake started was explained by the date when soil temperature matched the mean annual air temperature. We also observed a strong correlation between mean annual air temperature and the day that a deciduous forest starts to be a carbon sink. Consequently we are able to provide a simple phenological rule that can be implemented in regional carbon balance models and be assessed with soil and temperature outputs produced by climate and weather models.


Asunto(s)
Aire , Dióxido de Carbono/metabolismo , Carbono/metabolismo , Suelo , Temperatura , Asia , Clima , Europa (Continente) , América del Norte , Hojas de la Planta/crecimiento & desarrollo , Árboles
11.
Environ Monit Assess ; 27(3): 221-32, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24221026

RESUMEN

The purpose of this investigation was to monitor airborne dipersion of particulates in connection with exploration activities at a niobium-mineralization in the Sarfartoq area, SW Greenland, during the summer of 1989, and to provide a basis for monitoring strategies in later phases of the development of the mining site. During three periods moss bags were exposed at 9 stations close to the outcrop and at 3 background stations, and indigenous lichens and mosses were sampled before and after the exploration work.Analyses of element concentrations showed that the natural enrichment of elements in the indigenous vegetation is restricted to areas immediately at or on the outcrop. The elements found in elevated concentrations were Nb, La, Ce, Th and U.The moss bags and the indigenous monitor organisms showed rises in concentrations of the elements Nb, Ce, Cd, Pb and Zn after the exploration activities during the summer. This shows that some dispersion of dust has occurred in the area.

12.
Anal Quant Cytol Histol ; 18(4): 279-85, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8862669

RESUMEN

OBJECTIVE: To estimate the total number of glial fibrillary acidic protein (GFAP)-positive astrocytes and the volume of GFAP-positive structures in the left molecular layer of the dentate gyrus by unbiased methods to provide reference values for neurotoxicologic model studies. STUDY DESIGN: The number of astrocytes was estimated by the optical fractionator, and the volume of GFAP-positive structures was estimated by the Cavalieri principle in male Wistar rats at 3, 13 and 25 months of age. RESULTS: The number of astrocytes was statistically significantly increased in the oldest age group (111.000 +/- 11.000 [mean +/- SD]) as compared to the youngest group (88.000 +/- 15.000). The value for 13-month-old rats was intermediate (103.000 +/- 14.000). The GFAP volume per astrocyte was statistically significantly reduced in the oldest age group (441 +/- 103 microns 3) as compared to the youngest one (673 +/- 146). The GFAP volume per astrocyte of 13-month-old rats was intermediate (629 +/- 245). CONCLUSION: There is a slight increase in the number of astrocytes with age and a slight decrease in GFAP volume per astrocyte with age. Stereology combined with immunohistochemistry is a strong tool for estimation of the total number of accurately identified cells in different brain regions.


Asunto(s)
Astrocitos/metabolismo , Giro Dentado/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Factores de Edad , Animales , Giro Dentado/citología , Masculino , Ratas , Ratas Wistar
13.
Int Arch Allergy Immunol ; 130(1): 66-72, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12576737

RESUMEN

BACKGROUND: Other researchers have reported that the specific immune response to subsequent antigen challenge is primed in newborn mice or rats dosed orally by gavage. We wanted to investigate if priming of a subsequent specific IgE response could be achieved by dosing newborn rats orally with ovalbumin and if this method could be used in an animal model for food allergy. METHODS: Newborn Brown Norway rats were dosed with ovalbumin in the mouth (100 microg or 6 mg). As young adults, the animals were dosed by gavage for 35 days with 1 mg ovalbumin/day or once intraperitoneally with 100 microg. Control groups were dosed by gavage or intraperitoneally but not as neonates. Additionally, young adult rats were dosed with 1 mg ovalbumin/day in the mouth for 35 days. Sera from individual animals were analysed for specific IgE and specific IgG. RESULTS: In all experiments with neonatal rats the specific IgE and IgG responses were decreased compared to the control groups, however, not always reaching statistical significance. A statistical significant decrease in the specific immune response was found in young adult rats dosed in the mouth as compared to by gavage. CONCLUSIONS: Dosing Brown Norway rats with ovalbumin in the mouth as neonates do not prime the specific immune response. The decrease in immune response found in our experiments when dosing newborn animals in the mouth in opposition to the priming seen by others when dosing by intragastric intubation may be explained by a dissimilar antigen presentation when dosing includes both oral mucosa and gut.


Asunto(s)
Animales Recién Nacidos/inmunología , Modelos Animales de Enfermedad , Hipersensibilidad a los Alimentos/etiología , Ovalbúmina/inmunología , Animales , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Ratas , Ratas Endogámicas BN
14.
Environ Monit Assess ; 3(1): 13-22, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24258823

RESUMEN

Yarrow (Achillea millefolium L.) and 3 cryptogamic epiphytes were collected from and transplanted to 10 various locations in Denmark. The spatial and temporal variation in Pb and Cd concentrations of yarrow leaves and the cryptogams were determined. The physical structure of the plant parts, the mobility differences between the metals and the atmospheric fallout of metals at the growing site were believed to be important for the metal uptake. It was concluded, that yarrow leaves give a measure of the relative variation in deposition rates to surface of higher plants when collected at the end of a growth season, and that the geographic variation was revealed with similar accuracy by yarrow and the cryptogams.

15.
Nature ; 404(6780): 861-5, 2000 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-10786790

RESUMEN

Carbon exchange between the terrestrial biosphere and the atmosphere is one of the key processes that need to be assessed in the context of the Kyoto Protocol. Several studies suggest that the terrestrial biosphere is gaining carbon, but these estimates are obtained primarily by indirect methods, and the factors that control terrestrial carbon exchange, its magnitude and primary locations, are under debate. Here we present data of net ecosystem carbon exchange, collected between 1996 and 1998 from 15 European forests, which confirm that many European forest ecosystems act as carbon sinks. The annual carbon balances range from an uptake of 6.6 tonnes of carbon per hectare per year to a release of nearly 1 t C ha(-1) yr(-1), with a large variability between forests. The data show a significant increase of carbon uptake with decreasing latitude, whereas the gross primary production seems to be largely independent of latitude. Our observations indicate that, in general, ecosystem respiration determines net ecosystem carbon exchange. Also, for an accurate assessment of the carbon balance in a particular forest ecosystem, remote sensing of the normalized difference vegetation index or estimates based on forest inventories may not be sufficient.


Asunto(s)
Carbono/metabolismo , Árboles , Atmósfera , Ecosistema , Europa (Continente) , Oxígeno/metabolismo , Fotosíntesis , Suelo
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