25 research outputs found

    Size-dependence of volatile and semi-volatile organic carbon content in phytoplankton cells

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    The content of volatile and semivolatile organic compounds (VOC and SOC), measured as exchangeable dissolved organic carbon (EDOC), was quantified in 9 phytoplanktonic species that spanned 4 orders of magnitude in cell volume, by disrupting the cells and quantifying the gaseous organic carbon released. EDOC content varied 4 orders of magnitude, from 0.0015 to 14.12 pg C cell−1 in the species studied and increased linearly with increasing phytoplankton cell volume following the equation EDOC (pg C cell−1) = −2.35 × cellular volume (CV, μm3 cell−1) 0.90 (± 0.3), with a slope (0.90) not different from 1 indicating a constant increase in volatile carbon as the cell size of phytoplankton increased. The percentage of EDOC relative to total cellular carbon was small but varied 20 fold from 0.28 to 5.17%, and no obvious taxonomic pattern in the content of EDOC was appreciable for the species tested. The cell release rate of EDOC is small compared to the amount of carbon in the cell and difficult to capture. Nonetheless, the results point to a potentialf flux of volatile and semivolatile phytoplankton-derived organic carbon to the atmosphere that has been largely underestimated and deserves further attention in the future.This is a contribution to the “Malaspina 2010” COSOLIDER project funded by the Spanish Ministry of Science and Innovation (CSD2008-00077).Peer reviewedPeer Reviewe

    Obtención de biomasa de microalga Chlorella vulgaris en un banco de prueba de fotobiorreactores de columna de burbujeo

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    Dada la agudización de la situación socioeconómica y medioambiental que se enfrenta en la actualidad, los investigadores buscan nuevas alternativas para sustituir el combustible fósil convencional, siendo una salida, los biocombustibles obtenidos a partir de microalgas. El objetivo de esta investigación fue la obtención de biomasa en un banco de prueba de fotobiorreactores de columna de burbujeo, utilizando una cepa de Chlorella vulgaris en medio Bristol. Se dimensionó el fotobiorreactor y se evaluó la influencia de las variables pH y concentración de nitrógeno, con y sin presencia de oligoelementos, sobre la productividaddel crecimiento de la biomasa de microalgas. Seencontró que en el intervalo estudiado (pH entre 6 y 8 y concentración de NaNO3 entre 0,5 y 1 g/L) estas variables no tienen un efecto significativo en el crecimiento, mientras que la presencia de oligoelementos favorece este

    Thresholds of Contaminants: A Synthesis

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    A fundamental problem in ecotoxicology is the prediction of long term population and ecosystem-level effects of contaminant exposure based on dose response data of few individuals obtained over a short time period. In addition, environmental fluctuations will always affect significantly the population/ecosystem resilience. However, these fluctuations are not taken into account under dose-response experiments on individuals. In the Thresholds project we have analyzed some of these questions by using experiments, data analysis tools and modelling approaches. Several important finding may be summarized as follows: 1 Molecular level effects are detected even at concentrations that did not affect the macroscopic end point studied, i.e. growth rate. 2 Natural populations are more sensitive that populations in cultures. 3 There are differences for the same species at different environments, e.g. Mediterranean, Black Seas and Atlantic Ocean. 4 The environmental conditions and the time of release of the contaminant cause a variability of the response at ecosystem level that can reach 50%. 5 At the actual level of knowledge it is difficult to assess if the legal approach, based on the precautionary principle, is over or under conservative, when considering molecular and its long term effects, the combined effects of mixtures and the environmental fluctuations that affect all ecosystems. 6 A similar colour code to the one adopted for biological quality elements should be adopted for the definition of EQS, with values higher than the EQS as orange (poor). This will allow assessing contamination trends and an early detection of a chemical contamination problems. 7 In aquatic environments ecosystem experience the combined effects of mixtures. Ecotoxicological risk assessment should be performed taking this aspect into account. However, with the amount of new chemicals being produced and the detection limits required it is clear that new integrated indicators are necessary. Limiting the levels of certain chemicals in the environment is one step to improve ecosystem health but alone it will not prevent further deterioration. 8 Due to practical limitations, knowledge on ecotoxicology is only available for a small fraction of the anthropogenic chemical pressure. The importance of this simplification has not been comprehensibly assessed and introduce uncertainty in the appropriate outcome of current legislation and managing practices.JRC.H.5-Rural, water and ecosystem resource

    Cell size matters : nano- and micro-plastics preferentially drive declines of large marine phytoplankton due to co-aggregation

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    Marine plastic pollution represents a key environmental concern. Whilst ecotoxicological data for plastic is increasingly available, its impact upon marine phytoplankton remains unclear. Owing to their predicted abundance in the marine environment and likely interactions with phytoplankton, here we focus on the smaller fraction of plastic particles (~50 nm and ~2 µm polystyrene spheres). Exposure of natural phytoplankton communities and laboratory cultures revealed that plastic exposure does not follow traditional trends in ecotoxicological research, since large phytoplankton appear particularly susceptible towards plastics exposure despite their lower surface-to-volume ratios. Cell declines appear driven by hetero-aggregation and co-sedimentation of cells with plastic particles, recorded visually and demonstrated using confocal microscopy. As a consequence, plastic exposure also caused disruption to photosynthetic functioning, as determined by both photosynthetic efficiency and high throughput proteomics. Negative effects upon phytoplankton are recorded at concentrations orders of magnitude above those estimated in the environment. Hence, it is likely that impacts of NPs and MPs are exacerbated at the high concentrations typically used in ecotoxicological research (i.e., mg L-1)

    Use of non-steroidal anti-inflammatory drugs and risk of breast cancer: The Spanish Multi-Case-control (MCC) study

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    Background: The relationship between non-steroidal anti-inflammatory drug (NSAID) consumption and breast cancer has been repeatedly studied, although the results remain controversial. Most case-control studies reported that NSAID consumption protected against breast cancer, while most cohort studies did not find this effect. Most studies have dealt with NSAIDs as a whole group or with specific drugs, such aspirin, ibuprofen, or others, but not with NSAID subgroups according to the Anatomical Therapeutic Chemical Classification System; moreover, scarce attention has been paid to their effect on different tumor categories (i.e.: ductal/non-ductal, stage at diagnosis or presence of hormonal receptors). Methods: In this case-control study, we report the NSAID – breast cancer relationship in 1736 breast cancer cases and 1895 healthy controls; results are reported stratifying by the women’s characteristics (i.e.: menopausal status or body mass index category) and by tumor characteristics. Results: In our study, NSAID use was associated with a 24 % reduction in breast cancer risk (Odds ratio [OR] = 0.76; 95 % Confidence Interval [CI]: 0.64–0.89), and similar results were found for acetic acid derivatives, propionic acid derivatives and COXIBs, but not for aspirin. Similar results were found in postmenopausal and premenopausal women. NSAID consumption also protected against hormone + or HER2+ cancers, but not against triple negative breast cancers. The COX-2 selectivity showed an inverse association with breast cancer (i.e. OR < 1), except in advanced clinical stage and triple negative cancers. Conclusion: Most NSAIDs, but not aspirin, showed an inverse association against breast cancer; this effect seems to be restricted to hormone + or HER2+ cancers. Keywords: Breast cancer, Non-steroidal anti-inflammatory drug, Hormone receptor positive breast cancer, HER2 positive breast cancer, Triple negative breast cance

    Multiple Myeloma Treatment in Real-world Clinical Practice : Results of a Prospective, Multinational, Noninterventional Study

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    Funding Information: The authors would like to thank all patients and their families and all the EMMOS investigators for their valuable contributions to the study. The authors would like to acknowledge Robert Olie for his significant contribution to the EMMOS study. Writing support during the development of our report was provided by Laura Mulcahy and Catherine Crookes of FireKite, an Ashfield company, a part of UDG Healthcare plc, which was funded by Millennium Pharmaceuticals, Inc, and Janssen Global Services, LLC. The EMMOS study was supported by research funding from Janssen Pharmaceutical NV and Millennium Pharmaceuticals, Inc. Funding Information: The authors would like to thank all patients and their families and all the EMMOS investigators for their valuable contributions to the study. The authors would like to acknowledge Robert Olie for his significant contribution to the EMMOS study. Writing support during the development of our report was provided by Laura Mulcahy and Catherine Crookes of FireKite, an Ashfield company, a part of UDG Healthcare plc, which was funded by Millennium Pharmaceuticals, Inc, and Janssen Global Services, LLC. The EMMOS study was supported by research funding from Janssen Pharmaceutical NV and Millennium Pharmaceuticals, Inc. Funding Information: M.M. has received personal fees from Janssen, Celgene, Amgen, Bristol-Myers Squibb, Sanofi, Novartis, and Takeda and grants from Janssen and Sanofi during the conduct of the study. E.T. has received grants from Janssen and personal fees from Janssen and Takeda during the conduct of the study, and grants from Amgen, Celgene/Genesis, personal fees from Amgen, Celgene/Genesis, Bristol-Myers Squibb, Novartis, and Glaxo-Smith Kline outside the submitted work. M.V.M. has received personal fees from Janssen, Celgene, Amgen, and Takeda outside the submitted work. M.C. reports honoraria from Janssen, outside the submitted work. M. B. reports grants from Janssen Cilag during the conduct of the study. M.D. has received honoraria for participation on advisory boards for Janssen, Celgene, Takeda, Amgen, and Novartis. H.S. has received honoraria from Janssen-Cilag, Celgene, Amgen, Bristol-Myers Squibb, Novartis, and Takeda outside the submitted work. V.P. reports personal fees from Janssen during the conduct of the study and grants, personal fees, and nonfinancial support from Amgen, grants and personal fees from Sanofi, and personal fees from Takeda outside the submitted work. W.W. has received personal fees and grants from Amgen, Celgene, Novartis, Roche, Takeda, Gilead, and Janssen and nonfinancial support from Roche outside the submitted work. J.S. reports grants and nonfinancial support from Janssen Pharmaceutical during the conduct of the study. V.L. reports funding from Janssen Global Services LLC during the conduct of the study and study support from Janssen-Cilag and Pharmion outside the submitted work. A.P. reports employment and shareholding of Janssen (Johnson & Johnson) during the conduct of the study. C.C. reports employment at Janssen-Cilag during the conduct of the study. C.F. reports employment at Janssen Research and Development during the conduct of the study. F.T.B. reports employment at Janssen-Cilag during the conduct of the study. The remaining authors have stated that they have no conflicts of interest. Publisher Copyright: © 2018 The AuthorsMultiple myeloma (MM) remains an incurable disease, with little information available on its management in real-world clinical practice. The results of the present prospective, noninterventional observational study revealed great diversity in the treatment regimens used to treat MM. Our results also provide data to inform health economic, pharmacoepidemiologic, and outcomes research, providing a framework for the design of protocols to improve the outcomes of patients with MM. Background: The present prospective, multinational, noninterventional study aimed to document and describe real-world treatment regimens and disease progression in multiple myeloma (MM) patients. Patients and Methods: Adult patients initiating any new MM therapy from October 2010 to October 2012 were eligible. A multistage patient/site recruitment model was applied to minimize the selection bias; enrollment was stratified by country, region, and practice type. The patient medical and disease features, treatment history, and remission status were recorded at baseline, and prospective data on treatment, efficacy, and safety were collected electronically every 3 months. Results: A total of 2358 patients were enrolled. Of these patients, 775 and 1583 did and did not undergo stem cell transplantation (SCT) at any time during treatment, respectively. Of the patients in the SCT and non-SCT groups, 49%, 21%, 14%, and 15% and 57%, 20%, 12% and 10% were enrolled at treatment line 1, 2, 3, and ≥ 4, respectively. In the SCT and non-SCT groups, 45% and 54% of the patients had received bortezomib-based therapy without thalidomide/lenalidomide, 12% and 18% had received thalidomide/lenalidomide-based therapy without bortezomib, and 30% and 4% had received bortezomib plus thalidomide/lenalidomide-based therapy as frontline treatment, respectively. The corresponding proportions of SCT and non-SCT patients in lines 2, 3, and ≥ 4 were 45% and 37%, 30% and 37%, and 12% and 3%, 33% and 27%, 35% and 32%, and 8% and 2%, and 27% and 27%, 27% and 23%, and 6% and 4%, respectively. In the SCT and non-SCT patients, the overall response rate was 86% to 97% and 64% to 85% in line 1, 74% to 78% and 59% to 68% in line 2, 55% to 83% and 48% to 60% in line 3, and 49% to 65% and 36% and 45% in line 4, respectively, for regimens that included bortezomib and/or thalidomide/lenalidomide. Conclusion: The results of our prospective study have revealed great diversity in the treatment regimens used to manage MM in real-life practice. This diversity was linked to factors such as novel agent accessibility and evolving treatment recommendations. Our results provide insight into associated clinical benefits.publishersversionPeer reviewe

    Thresholds and points of no return for oceanic phytoplankton: effects of pollution on phytoplankton communities

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    [eng] Since the Industrial Revolution, significant amounts of natural and synthetic compounds have been released to the environment, interacting with the natural biogeochemical cycles. In oceans, these cycles are partly controlled by phytoplankton. Phytoplankton is the primary producer in the ocean, responsible of inorganic carbon fixation and its transformation and incorporation to the ecosystem as organic carbon. The high mortality observed in the last times by phytoplankton implies that the carbon incorporated cannot be transferred either to the trophic chain nor sedimented with the cells to the ocean bottom, highly influencing the carbon fluxes in the ocean. Among the different factors inducing phytoplankton mortality, exposition to toxic pollutants has been observed as one of the factors causing it. Through multiple experiments with metals and Persistent Organic Pollutants (POPs), several pollution thresholds to marine phytoplankton have been determined during this doctoral thesis. Thresholds are the critical values around which the ecosystem flips from one stable state to another, becoming points of no return when crossing again the same value in the opposite direction does not restore the initial state. Thus, the objectives of this doctoral thesis were to quantify those thresholds, to determine the parameters controlling their sensitivity to marine pollution and to analyze the joint action of mixtures of pollutants and the joint action of these pollutants with environmental factors. This doctoral thesis is the result of these experiments and their findings.[spa] Desde la Revolución Industrial, cantidades significativas de compuestos naturales y sintéticos han sido liberados al medio ambiente, interactuando con los ciclos biogeoquímicos naturales. En los océanos, estos ciclos son controlados en parte por el fitoplancton. El fitoplancton es el principal productor del océano, responsable de la fijación de carbono inorgánico y su transformación e incorporación a los ecosistemas como carbono orgánico. La elevada mortalidad observada en los últimos tiempos por el fitoplancton implica que el carbono no pueda ser transferido ni a la cadena trófica ni sedimentada con las células al fondo del océano, influyendo en los flujos de carbono en el océano. Entre los diferentes factores que inducen la mortalidad del fitoplancton, la exposición a los contaminantes tóxicos se ha observado como uno de los factores que lo causan. A través de múltiples experimentos con metales y contaminantes orgánicos persistentes (POPs), se han determinado numerosos umbrales de contaminación para el fitoplancton marino durante esta tesis doctoral. Los umbrales son los valores críticos en torno a los cuales el ecosistema pasa de un estado estable a otro, convirtiéndose en puntos de no retorno cuando cruzar de nuevo el mismo valor en la dirección opuesta no restaura el estado inicial. Así, los objetivos de esta tesis doctoral fueron cuantificar dichos umbrales, determinar los parámetros que controlan la sensibilidad a la contaminación marina y analizar la acción conjunta de mezclas de contaminantes y la acción conjunta de estos contaminantes con factores ambientales. Esta tesis doctoral es el resultado de estos experimentos y sus hallazgos.[cat] Desde la Revolució Industrial, quantitats significatives de compostos naturals i sintètics han estat alliberats al medi ambient, interactuant amb els cicles biogeoquímics naturals. En els oceans, aquests cicles són controlats en part pel fitoplàncton. El fitoplàncton és el principal productor de l'oceà, responsable de la fixació de carboni inorgànic i la seva transformació i incorporació als ecosistemes com carboni orgànic. L'elevada mortalitat observada en els darrers temps pel fitoplàncton implica que el carboni no pugui ser transferit ni a la cadena tròfica ni sedimentada amb les cèl lules al fons de l'oceà, influint en els fluxos de carboni en l'oceà. Entre els diferents factors que indueixen la mortalitat del fitoplàncton, l'exposició als contaminants tòxics s'ha observat com un dels factors que el causen. A través de múltiples experiments amb metalls i contaminants orgànics persistents (POPs), s'han determinat nombrosos llindars de contaminació per al fitoplàncton marí durant la tesi doctoral. Els llindars són els valors crítics al voltant dels quals l'ecosistema passa d'un estat estable a un altre, convertint-se en punts de no retorn quan creuar de nou el mateix valor en la direcció oposada no restaura l'estat inicial. Així, els objectius d'aquesta tesi doctoral van ser quantificar aquests llindars, determinar els paràmetres que controlen la sensibilitat a la contaminació marina i analitzar l'acció conjunta de mescles de contaminants i l'acció conjunta d'aquests contaminants amb factors ambientals. Aquesta tesi doctoral és el resultat d'aquests experiments i les seves troballes

    Cell size dependent toxicity thresholds of polycyclic aromatic hydrocarbons to natural and cultured phytoplankton populations

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    The toxicity of pyrene and phenanthrene to phytoplankton was studied by analyzing the effect on the growth, abundance and cell viability of cultured species and natural communities of the Atlantic Ocean and the Mediterranean Sea. A decrease in cell abundance, and growth rate was observed as concentration of PAHs increased, with catastrophic cell mortality induced at the highest PAH concentration tested. A strong positive linear relationship was observed between the LC50 (the PAH concentration at which cell population will decline by a half), and the species cell volume, for both phenanthrene and pyrene. Natural communities were however significantly more sensitive to PAHs than cultured phytoplankton, as indicated by the lower slope (e.g. 0.23 and 0.65, respectively, for pyrene) of the relationship LC50 vs. cell volume. The results highlight the importance of cell size in determining the phytoplankton sensitivity to PAHs identifying the communities from the oligotrophic ocean to be more vulnerable.This study was supported by a Spanish doctoral fellowship from the Conselleria d'Economía, Hisenda i Innovació del Govern de les Illes Balears, to P. Echeveste, and by the research projects “Thresholds of Environmental Sustainability (Thresholds)” 6th Framework Program, CE; and “RODA: Oceanic Eddies and Atmospheric deposition: Biological and Biogeochemical Effects in Superficial Waters of the East Atlantic” funded by the Spanish Ministry of Education and Science (CTM2004-06842-C03-02/MAR). We thank N. Berrojalbiz and S. del Vento for the contaminant solutions. We are grateful to the crew aboard the Garcia del Cid and Hesperides research vessels for their help during the cruises.Peer reviewe

    Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton

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    Polycyclic Aromatic Hydrocarbons' (PAHs) toxicity is enhanced by the presence of ultraviolet radiation (UVR), which levels have arisen due to the thinning of the ozone layer. In this study, PAHs' phototoxicity for natural marine phytoplankton was tested. Different concentrations of a mixture of 16 PAHs were added to natural phytoplankton communities from the Mediterranean Sea, Atlantic, Arctic and Southern Oceans and exposed to natural sunlight received in situ, including treatments where the UVR bands were removed. PAHs' toxicity was observed for all the phytoplankton groups studied in all the waters and treatments tested, but only for the pico-sized group a synergetic effect of the mixture and UVR was observed (p = 0.009). When comparing phototoxicity in phytoplankton from oligotrophic and eutrophic waters, synergy was only observed at the oligotrophic communities (p = 0.02) where pico-sized phytoplankton dominated. The degree of sensitivity was related to the trophic degree, decreasing as Chlorophyll a concentration increased. © 2011 Elsevier Ltd. All rights reserved.Peer Reviewe

    Decrease in the abundance and viability of oceanic phytoplankton due to trace levels of organic pollutants

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    Trabajo presentado en la SETAC Europe 20th Annual Meeting, celebrada en Sevilla, España, del 23 al 27 de mayo de 2010Peer Reviewe
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