118 research outputs found

    Hazard characterization of graphene nanomaterials in the frame of their food risk assessment: A review

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    Different applications have been suggested for graphene nanomaterials (GFNs) in the food and feed chain. However, it is necessary to perform a risk assessment before they become market-ready, and when consumer exposure is demonstrated. For this purpose, the European Food Safety Authority (EFSA) has published a guidance that has been recently updated. In this sense, the aim of this study is to identify and characterise toxicological hazards related to GFNs after oral exposure. Thus, existing scientific literature in relation to in vitro degradation studies, in vitro and in vivo genotoxicity, toxicokinetics data, in vivo oral studies, and other in-depth studies such as effects on the microbiome has been revised. The obtained results showed that the investigations performed up to now did not follow internationally agreed-upon test guidelines. Moreover, GFNs seemed to resist gastrointestinal digestion and were able to be absorbed, distributed, and excreted, inducing toxic effects at different levels, including genotoxicity. Also, dose has an important role as it has been reported that low doses are more toxic than high doses because GFNs tend to aggregate in the digestive system, changing the internal exposure scenario. Thus, further studies including a thorough toxicological evaluation are required to protect consumer's safety.Junta de Andalucía US-1259106, P18-RT-199

    Intrinsic value of the impact factor of scientific journals

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    Se analiza el porqué de las citaciones de los artículos. Se realizan también algunas consideraciones sobre el factor de impacto de las revistas, sus ventajas y sus posibles defectos. El factor de impacto de las revistas, desde su popularización por el Institute for Scientific Information, ha tomado una gran importancia como parámetro objetivo de evaluación de las revistas científicas y, por extensión, de todo lo que las rodea. No hay correlación con el desfase en factores de impacto de algunas revistas anglosajonas y el de las revistas escritas en otros idiomas. Probablemente se benefician de publicar en inglés y del llamado “efecto Mateo”, según el cual los investigadores científicos eminentes cosechan aplausos mucho más nutridos que otros investigadores, menos conocidos, por contribuciones equivalentes. Es paradójico también que los grandes descubrimientos de nuestra época no figuren entre los 100 artículos más citados. No hay tampoco una correlación entre todos los artículos aparecidos en una publicación y su factor de impacto; la mitad de los artículos de una revista son citados diez veces más que la otra mitad. Los artículos citados 0 veces reciben el mérito de los mejores. Lo ortodoxo sería utilizar en cada artículo el número de citas que recibe, que sería su propio factor de impacto y, para los autores, el índice H.The reason of higher number of citations of some articles is discussed. Some considerations about the journals’ impact factor, its merits and its pitfalls are also made. Scientific journals’ impact factor, popularized by the Institute for Scientific Information, has become an objective parameter for authors’ evaluation and also for institutions and other related circumstances. There is no reason for the impact factor’s gap between some English journals and those written in other languages. English journals probably benefit of the “Mathew’s effect”, according to which eminent scientists are more rewarded by similar contributions than others less known. It is paradoxical that most of the major achievements of our age do not appear among the 100 most cited articles. There is no homogeneity among all the articles appearing in each scientific journal: half of the articles are cited ten times more than the other half. However, those articles cited 0 times are credited like the better ones. Each article should be evaluated by its own citations, which would be its impact factor; the authors should be evaluated by their H index

    The ten most cited articles of the journal “Nutricion Hospitalaria”

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    Después de 36 años de publicación ininterrumpida de la revista Nutrición Hospitalaria, hemos recopilado los diez artículos más citados. Se muestra también la relación de los diez artículos con más citas a escala mundial; asimismo se estratifican las citaciones según el idioma, inglés o español, la temática o los años analizados. Nutr. Hosp. es, a nivel mundial, la revista de nutrición ibero-latinoamericana mejor valorada. Por el volumen de artículos publicados, con 369 ítems citables en 2014, Nutr Hosp se sitúa en cuarto lugar de todas las revistas de nutrición. Permitir la publicación de artículos en inglés o hacerlo simultáneamente en castellano y en inglés, así como estar en régimen de “Open Access” sin restricción de ningún tipo en la difusión desde el momento de aparición de los artículos, son probablemente elementos favorecedores de las citas.After 36 years of continued publication of the journal Nutrición Hospitalaria, a list with the ten most cited articles published in it is elaborated. The top ten most cited articles in the world literature and stratification according to language, English or Spanish, subject, or period of time published are also analyzed. Nutr Hosp is the most important Ibero latin American nutrition journal. Nutr Hosp published 369 items in 2014 gaining the fourth position among all the world’s journals devoted to nutrition. Article publication in English, or simultaneously in Spanish and English and Open Access policy probably benefit the number of citations

    Dispositivo de fijación, cierre y acoplamiento para catéter de perfusión intravenosa

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    Introducción: los medios de fijación a la piel de un catéter venoso periférico, de un catéter venoso central o de un catéter arterial central presentan los siguientes graves inconvenientes: ser la sede de infecciones a nivel del lugar de la punción, provocar una saturación de la zona anatómica, la cual resulta muy difícil de soportar e incómodo para el paciente portador, y suponer un riesgo para el personal de enfermería cuando se usan hilos de sutura para fijar el soporte del catéter. Objetivo: por lo anteriormente expuesto, se ha detectado la necesidad de diseñar un dispositivo que reduzca la complejidad y aparatosidad de los sistemas conocidos y empleados en la actualidad, favoreciendo la asepsia y la movilidad del paciente. Método: el desarrollo presentado en este artículo se refiere a un sistema mecánico de fijación, cierre y acoplamiento para catéter de perfusión intravenosa. El sistema dispone de una pieza circular de pequeño espesor con al menos dos orificios para su fijación subcutánea, centralmente de uno o más conductos para acoplar lúmenes, y de una parte cilíndrica hueca que sobresale a uno de los lados, exteriormente roscada e interiormente lisa con un tetón de posición. Para uso domiciliario se dispone de un tapón de estanqueidad con uno o más tubos de pequeño diámetro que se acoplan en los orificios para lúmenes, una ranura de posición, un tirador y un tapón roscado ciego para el cierre hermético con la parte roscada. Para uso hospitalario se dispone de un tapón intermedio con una o más entradas para lúmenes, así como de un tapón roscado hueco que permite su acoplamiento hermético con la parte roscada. Resultados: el desarrollo descrito en este artículo va a ser utilizado en dos ambientes: ambiente domiciliario y ambiente hospitalario. Además, reduce el riesgo de infección y saturación de la zona anatómica de los pacientes en los que se realiza la punción cutánea en la que se fijan catéteres venosos periféricos, catéteres venosos centrales o catéteres arteriales centralesIntroduction: skin fixing devices in peripheral, central or arterial catheters have several important drawbacks: site infection, stacking of material in the anatomical area which is very annoying for the patient and medical staff risk when fixating stitches are used. Objective: to develop a fixing device that simplifies presently used systems, favoring asepsis and motility. Methods: the device herein described is composed by a mechanical fixation, a closing system and coupling for intravenous catheters. The system has a thin circular piece with at least two holes for subcutaneous fixation, one or several conducts for lumina and a hollow cylindrical part in one side, screwed exteriorly and flat inside, with an oriented protuberance. A watertight plug with one or several thin tubes that adapt to the lumina, a positional slot, a handle and a solid screwed tap for perfect closure are available for at home use. An intermediate plug with one or several lumina and a screwed hollow plug are provided for in hospital use. Results: the above described device is intended to be used in two settings: in hospital and at home. It is supposed to reduce the risk of infection and stacking of the anatomical site where cutaneo us puncture with fixation of peripheral, central or arterial catheters is performe

    Ciclo gametogénico de Venerupis rhomboides Pennant, 1777 en el litoral Andaluz (sur España)

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    Knowledge of the reproductive biology of a species is essential for fishery management and for its culture. However, there are no previous studies in Andalusia regarding the determination of the gametogenic cycle of Venerupis rhomboides. The aim of this paper was to determine the sex ratio of a Mediterranean population of this species, to describe the gametogenic cycle using histological techniques and the condition index and to determine the relations with temperature and chlorophyll a levels. The sex-ratio was 1:1 (?2 = 0.724; p > 0.25). Spawning and post-spawning specimens were observed throughout this study, with the highest peak in april. The condition index did not reflect exactly the reproductive activity of V. rhomboides. One possible explanation was the asynchronous character of the population. The more or less constant temperature, and the variations of chlorophyll a, did not seem to be limiting for gonadal maturation and spawning over the whole annual cycle.El conocimiento de la biología reproductiva de una especie es fundamental para la gestión de la pesquería y para su cultivo. Venerupis rhomboides, es una especie de interés comercial en la costa sur de España pero no existen estudios previos que aporten datos sobre su biología. El objetivo fundamental de este trabajo fue el estudio del ciclo gametogé- nico en una población de V. rhomboides del Mediterráneo andaluz. Para ello, se establecieron los siguientes objetivos específicos: estimación del ciclo gametogénico mediante la utilización de técnicas histológicas e índice de condición, determinación de la proporción de sexos y por último, la influencia de la temperatura y de los niveles de clorofila a sobre este ciclo. En el ciclo gametogénico, se observaron ejemplares en desove y post-emisión a lo largo de todo el periodo de estudio, encontrando el pico máximo de desove en abril. La proporción de sexos obtenida fue 1:1 (?2 = 0.724; p > 0.25). Las variaciones que experimentó el índice de condición no reflejaron exactamente la actividad reproductiva de V. rhomboides. Una posible explicación se atribuyó al carácter asincrónico de la población. La temperatura más o menos constante y las variaciones de la clorofila a no parecen limitar la maduración gonadal y la emisión de gametos durante todo el ciclo anual

    Charge transfer-assisted self-limited decyanation reaction of TCNQ-type electron acceptors on Cu(100)

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    TCNQ derivatives adsorbed on a metal surface undergo a self-limited decyanation reaction that only affects two out of the four cyano groups in the molecule. Combined Scanning Tunneling Microscopy/X-ray Photoelectron Spectroscopy experiments and Density Functional Theory calculations relate the self-limiting behavior to the transfer of electrons from the metal to the moleculeWe thank the CCC-UAM and the RES for allocation of computer time. Our work has been supported by the MINECO of Spain (MAT2009-13488, FIS2010-18847, FIS2010-15127, FIS2012-33011, CTQ2010-17006, CTQ2011-24652/BTQ), Comunidad de Madrid (Nanobiomagnet S2009/MAT-1726, Madrisolar-2 S2009/PPQ-1533), CONSOLIDER-INGENIO on Molecular Nanoscience (CSD2007- 00010) and European Union (SMALL PITN-GA-2009-23884

    In vivo genotoxicity evaluation of cylindrospermopsin in rats using a combined micronucleus and comet assay

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    Cylindrospermopsin (CYN) is a potent cyanotoxin recognized as an emerging human threat due to its cytotoxicity and potential carcinogenicity. Although the genotoxicity of CYN has been extensively studied in vitro, limited data are available on its in vivo genotoxicity. The aim of this study was to evaluate the in vivo genotoxicity of pure CYN (7.5–75 μg/kg body weight) after oral exposure of rats through a combined assay of the micronucleus test (MN) in bone marrow, and the standard and modified comet assay in stomach, liver and blood. Also, histopathological changes in stomach and liver were evaluated. Positive results in the MN test were observed in bone marrow in the exposed rats at all the tested concentrations. However, the comet assay revealed that CYN did not induce DNA strand breaks nor oxidative DNA damage in any of the tissues investigated. Finally, histopathological changes were observed in stomach and liver (7.5–75 μg/kg) in intoxicated rats. These results could indicate that CYN is able to induce irritation in stomach before its biotransformation in rats orally exposed, and genotoxicity in bone marrow.Ministerio de Economía y Competitividad (AGL2015-64558-R, MINECO/FEDER, UE

    Detection of cylindrospermopsin and its decomposition products in raw and cooked fish (Oreochromis niloticus) by analytical pyrolysis (Py-GC/MS)

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    The presence of the toxin cylindrospermopsin is increasingly frequent in samples from different ecosystems and it is a serious problem both at environmental level and for animal and human health. To be able to prevent CYN exposure risk, it is important to have suitable analytical methods, but also quick and economical ones. Analytical pyrolysis coupled to GC/MS (Py-GC/MS) represents an important alternative for the rapid detection, characterization or “fingerprinting” of different materials. However, it has been less studied with cyanotoxins up to date. The present work aims to investigate: 1) the suitability of Py-GC/MS for detection of CYN and its decomposition products in raw and cooked fish samples before consumption and 2) the influence of the different cooking methods on the presence of different CYN degradation products detected by Py-GC/MS. For first time, these results present that Py-GC/MS could be a rapid and economical alternative for the detection and monitoring of CYN and its degradation products (DP. m/z 290.1, 169.1 and 336.2) in raw or cooked fish. Moreover, the changes induced in CYN and DP by cooking could be amenable and detected by Py-GC/MS.Ministerio de Economía y Competitividad AGL2015-64558-R, CGL2016-78937-

    Genotoxicity Evaluation of Two Derived Products from Allium Extracts: s-propylmercaptocysteine and s-propyl Mercaptoglutathione

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    Propyl-propane-thiosulfonate (PTSO) is one of the main organosulfur compounds present in Allium essential oils with a widely documented biological activity. For this reason, it could be used as a food and feed additive in the agri-food industry. A genotoxicity evaluation of substances and their metabolites present in food is necessary to guarantee the consumer's health following the recommendations of the European Food Safety Authority (EFSA). To evaluate the toxicological profile of derivatives of PTSO, the cytotoxicity, an Ames test, a micronucleus test and the comet assay were performed. Results showed that non-cytotoxic effects were observed in Caco-2 exposed to s-propyl mercaptocysteine (CSSP) and s-propyl mercaptoglutathione (GSSP) (0–450 μM). The mutagenicity index remained in the range of 0.6–1.4 for both compounds, showing no mutagenic effects for the concentrations of 5000–312.5 μg GSSP/plate and 250–15.63 μg CSSP/plate. Moreover, the % binucleated cells with micronuclei were 1.3–2.2 and 1.6–2.7 for GSSP and GSSP, respectively. For comet assays there was no DNA-genotoxic or oxidative damage in a concentration range of 112.5–450 μM. Therefore, we can conclude that these compounds are not genotoxic at the conditions tested. These results support that the presence of CSSP and GSSP in the food/feed is not of concern, although further studies are needed to complete their safety profile.Junta de Andalucía AT17_5323_USE, P18-TP-2147Ministerio de Ciencia, Innovación y Universidades FPU2019-0124
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