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1.
Mar Pollut Bull ; 199: 116010, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211539

RESUMO

Sediments sampled at the estuary of the Oka River in the biosphere reserve of Urdaibai, Spain were analyzed for trace elements. Sediments were collected at 45 points of the estuary and the concentration of 14 elements was measured. The geoaccumulation indexes (Igeo), Normalized Average Weighted Concentrations (NAWC) and mean Effect Range-Median quotients (mERMq) were calculated. The results obtained were complementary and allowed intra- and inter-estuary comparison. According to the present findings, the estuary was classified as healthy, since the anthropogenic contribution of metals and metalloids was generally small. However, shipping and fishing activities at the ports of Bermeo and Mundaka and urban and industrial wastes from Gernika were regarded as the major pollution sources. Nevertheless, only slightly contaminated and toxic sediments, especially related to Ni and Cu, were found in the towns of Gernika and Mundaka.


Assuntos
Metaloides , Metais Pesados , Poluentes Químicos da Água , Metais Pesados/análise , Metaloides/análise , Estuários , Rios , Espanha , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Poluentes Químicos da Água/análise
2.
Anal Chim Acta ; 1276: 341632, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37573113

RESUMO

In this work, a geological sample of great astrobiological interest was studied through analytical techniques that are currently operating in situ on Mars and others that will operate in the near future. The sample analyzed consisted of an oncoid, which is a type of microbialite, collected in the Salar Carachi Pampa, Argentina. The main peculiarity of microbialites is that they are organo-sedimentary deposits formed by the in situ fixation and precipitation of calcium carbonate due to the growth and metabolic activities of microorganisms. For this reason, the Carachi Pampa oncoid was selected as a Martian analog for astrobiogeochemistry study. In this sense, the sample was characterized by means of the PIXL-like, SuperCam-like and SHERLOC-like instruments, which represent instruments on board the NASA Perseverance rover, and by means of RLS-like and MOMA-like instruments, which represent instruments on board the future ESA Rosalind Franklin rover. It was possible to verify that the most important conclusions and discoveries have been obtained from the combination of the results. Likewise, it was also shown that Perseverance rover-like remote-sensing instruments allowed a first detailed characterization of the biogeochemistry of the Martian surface. With this first characterization, areas of interest for in-depth analysis with Rosalind Franklin-like instruments could be identified. Therefore, from a first remote-sensing elemental identification (PIXL-like instrument), followed by a remote-sensing molecular characterization (SuperCam and SHERLOC-like instruments) and ending with an in-depth microscopic analysis (RLS and MOMA-like instruments), a wide variety of compounds were found. On the one hand, the expected minerals were carbonates, such as aragonite, calcite and high-magnesium calcite. On the other hand, unexpected compounds consisted of minerals related to the Martian/terrestrial surface (feldspars, pyroxenes, hematite) and organic compounds related to the past biological activity related to the oncoid (kerogen, lipid biomarkers and carotenes). Considering samples resembling microbialites have already been found on Mars and that one of the main objectives of the missions is to identify traces of past life, the study of microbialites is a potential way to find biosignatures protected from the inhospitable Martian environment. In addition, it should be noted that in this work, further conclusions have been obtained through the study of the results as a whole, which could also be carried out on Mars.

3.
Anal Chim Acta ; 1209: 339837, 2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35569848

RESUMO

The SuperCam instrument, onboard the Perseverance rover (Mars 2020 mission) is designed to perform remote analysis on the Martian surface employing several spectroscopic techniques such as Laser Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman (TRR), Time-Resolved Fluorescence (TRF) and Visible and Infrared (VISIR) reflectance. In addition, SuperCam also acquires high-resolution images using a color remote micro-imager (RMI) as well as sounds with its microphone. SuperCam has three main subsystems, the Mast Unit (MU) where the laser for chemical analysis and collection optics are housed, the Body Unit (BU) where the different spectrometers are located inside the rover, and the SuperCam Calibration Target (SCCT) located on the rover's deck to facilitate calibration tests at similar ambient conditions as the analyzed samples. To perform adequate calibrations on Mars, the 22 mineral samples included in the complex SCCT assembly must have a very homogeneous distribution of major and minor elements. The analysis and verification of such homogeneity for the 5-6 replicates of the samples included in the SCCT has been the aim of this work. To verify the physic-chemical homogeneity of the calibration targets, micro Energy Dispersive X-ray Fluorescence (EDXRF) imaging was first used on the whole surface of the targets, then the relative abundances of the detected elements were computed on 20 randomly distributed areas of 100 × 100 µm. For those targets showing a positive Raman response, micro-Raman spectroscopy imaging was performed on the whole surface of the targets at a resolution of 100 × 100 µm. The %RSD values (percent of relative standard deviation of mean values) for the major elements measured with EDXRF were compared with similar values obtained by two independent LIBS set-ups at spot sizes of 300 µm in diameter. The statistical analysis showed which elements were homogeneously distributed in the 22 mineral targets of the SCCT, providing their uncertainty values for further calibration. Moreover, nine of the 22 targets showed a good Raman response and their mineral distributions were also studied. Those targets can be also used for calibration purposes of the Raman part of SuperCam using the wavenumbers of their main Raman bands proposed in this work.


Assuntos
Meio Ambiente Extraterreno , Marte , Calibragem , Meio Ambiente Extraterreno/química , Minerais/análise , Análise Espectral Raman/métodos
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 251: 119443, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33485243

RESUMO

The landing site of the next planetary mission lead by ESA (ExoMars 2022) will be Oxia Planum. This location has been chosen due to different reasons, among them, the existence of sedimentary rocks that could host remains of organic matter. The fact that this type of rocks coexists with volcanic ones makes of high importance the study of the processes and the possible interactions that could happen among them. Therefore, in this research work the Armintza outcrop (Biscay, North of Spain) is proposed as an Oxia Planum analogue since it has the dichotomy of volcanic and sedimentary rock layers that is expected on the landing site of the ExoMars 2022 mission. As Raman and visible near infrared spectroscopies will be in the payload of the rover of that mission, they have been used to characterize the samples collected in the Armintza outcrop. With the help of these techniques, feldspars (albite mainly) and phyllosilicates (kaolinite and dickite, together with micas and chlorite minerals) have been identified as the major products on the samples, together with some weathering products (carbonates, sulphates, oxides) and apatite. Moreover, remains of kerogen have been detected in the sedimentary layers in contact with the interlayered lava flows, confirming the capability of similar sedimentary-volcanic layers to trap and store organic remains for millions of years. After establishing which compounds have volcanic or sedimentary origin, and which must be considered alteration phases, we can consider Armintza as a good Oxia Planum analogue.

5.
Talanta ; 224: 121863, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379074

RESUMO

This work proposes an innovative non-destructive analytical strategy, based on Confocal Raman micro-spectroscopy, High Resolution Raman Imaging and micro-X-Ray Fluorescence imaging, as part of the quick non-destructive techniques that could be used to characterize the Martian samples from the Mars Sample Return mission when back on Earth. Until that moment, Martian Meteorites are the only Martian samples in our hands to develop such Analytical Strategies. To demonstrate its capabilities, this analytical strategy has been applied to characterize the Dar al Gani 735 Martian Meteorite with the aim to identify the terrestrial and non-terrestrial alterations suffered by the meteorite as a very valuable complementary methodology to the more traditional petrographic analyses and single point measurements. The combination of these techniques allows extracting at the same time elemental, molecular and structural information of the studied area of the sample. The most relevant results on the analyzed DaG 735 shergottite thick samples revealed the presence of several altered mineral phases originated from the temperature and pressure conditions during the shock on Mars (anhydride, calcite and ilmenite), as well as from terrestrial weathering processes that degraded the meteorite from its landing on Earth (calcite and hematite in fractures together with gypsum, mirabilite and thenardite). As most of the conclusive results come from Raman spectroscopy, this study shows the potential of Raman spectroscopy as a key technique in the upcoming new explorations of Mars materials by the Rosalind Franklin rover (Exomars2022 mission from ESA) and the Perseverance rover (Mars2020 mission from NASA), where Raman spectrometers are mounted for the first time in an extra-terrestrial research in the field.

6.
Space Sci Rev ; 216(8): 138, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281235

RESUMO

SuperCam is a highly integrated remote-sensing instrumental suite for NASA's Mars 2020 mission. It consists of a co-aligned combination of Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman and Luminescence (TRR/L), Visible and Infrared Spectroscopy (VISIR), together with sound recording (MIC) and high-magnification imaging techniques (RMI). They provide information on the mineralogy, geochemistry and mineral context around the Perseverance Rover. The calibration of this complex suite is a major challenge. Not only does each technique require its own standards or references, their combination also introduces new requirements to obtain optimal scientific output. Elemental composition, molecular vibrational features, fluorescence, morphology and texture provide a full picture of the sample with spectral information that needs to be co-aligned, correlated, and individually calibrated. The resulting hardware includes different kinds of targets, each one covering different needs of the instrument. Standards for imaging calibration, geological samples for mineral identification and chemometric calculations or spectral references to calibrate and evaluate the health of the instrument, are all included in the SuperCam Calibration Target (SCCT). The system also includes a specifically designed assembly in which the samples are mounted. This hardware allows the targets to survive the harsh environmental conditions of the launch, cruise, landing and operation on Mars during the whole mission. Here we summarize the design, development, integration, verification and functional testing of the SCCT. This work includes some key results obtained to verify the scientific outcome of the SuperCam system.

7.
Folia Morphol (Warsz) ; 78(3): 626-629, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30484272

RESUMO

This project has been developed for many years in the Human Anatomy courses.Its good outcomes have been confirmed by years of evidence of excellent resultsobtained through the learning of Human Anatomy. This method of teaching andlearning as one allows students who are taking Human Anatomy classes to receivepractical training in small groups and transmit it to their colleagues in the practicaltraining established in the Medical degree. Table Leaders feel rewarded as theylearn to speak in public, regularly transmitting the knowledge obtained, and byhaving to be up to date with their studies. These are all aspects that help, not onlythe Table Leaders process of learning, but also that of their colleagues, who seeclosely and carefully anatomical details that help them understand the subject.This method of supporting practical training is always under the supervision ofthe teacher who develops the practical classes. These Leaders used to pass thetest without additional problems. Thus the note was significantly increased versusthe class colleagues.


Assuntos
Anatomia/educação , Comportamento Cooperativo , Modelos Anatômicos , Avaliação Educacional , Humanos
8.
Rev. colomb. enferm ; 13(1): 90-99, Octubre de 2016.
Artigo em Espanhol | LILACS, BDENF - Enfermagem, COLNAL | ID: biblio-999924

RESUMO

Es frecuente que los cuidadores principales de enfermos crónicos se conviertan en el "enfermo invisible", en la medida en que la atención y el \r\ncuidado están mayormente enfocados en el paciente, lo cual vulnera aspectos físicos, emocionales, espirituales y económicos de la persona que \r\ncuida. El objetivo de este estudio descriptivo con enfoque cualitativo es evaluar los resultados de implementar un programa educativo de inter\r\n-\r\nvención dirigido a 19 cuidadores principales de personas con enfermedad crónica, en seis delegaciones de la ciudad de Toluca, Estado de México. El estudio se desarrolló en tres etapas: diagnóstico, intervención y evaluación. Para impartir el programa educativo se realizaron visitas domiciliarias \r\nque se registraron en la bitácora de campo. \r\nEl programa denominado Cuidando a Cuidadores, se basa en los tres indicadores propuestos por \r\nNkongho: conocimiento, valor y paciencia. Consta de tres módulos, y en cada uno se realizaron tres tallerescon los 19 cuidadores,previo consen\r\n-\r\ntimiento informado. Los participantes expresaron haber adquirido conocimientos necesarios para el cuidado de su familiar; las dinámicas les \r\npermitieron reconocer fortalezas, debilidades, miedos, inseguridades y frustraciones; además, manifestaron sentirse satisfechos con el acom\r\n-\r\npañamiento y guía del equipo de salud que participó. Se puede afirmar que ser cuidador principal de un enfermo crónico es una experiencia \r\nque transforma la vida y requiere conocimiento, valor y paciencia para ejercer su tarea de manera hábil; esto puede incrementarse si se recibe \r\norientación por parte de los profesionales de enfermería


Regularly, the primary caregivers of chronically ill patients \r\nbecome the "invisible ill", to the extent that the attention and \r\ncare are mostly focused on the sick patiente, violating physical, \r\nemotional, spiritual and economic aspects of the caregiver. This \r\nproject analizes the results obtained from the implementation \r\nof an educational intervention program aimed at 19 primary \r\ncaregivers of people with chronic disease, in six delegations \r\nfrom the city of Toluca, State of Mexico. It was a descriptive \r\nstudy with a qualitative methodological approach. It was \r\ncarried out in three stages: diagnosis, intervention and evalua\r\n-\r\ntion. In order to provide the educational program, home visits \r\nwere performed using the log field. The program consisted \r\nof three modules, being imparted in workshops to the 19 \r\ncaregivers, with informed consent prior to the program. The \r\nresults were the following: Caregivers expressed that they had \r\nacquired knowledge required for the care of their family, the \r\ndynamics allowed them to recognize strengths, weaknesses, \r\nfears, insecurities and frustrations; they said they were satis\r\n-\r\nfied with the support and guidance of the health team that \r\nparticipated. It can be said that to be a primary caregiver for a \r\nchronically ill person is an experience that transforms life and \r\nrequires knowledge, courage and patience to perform their \r\nduties skillfully; these gratification may also be increased if you \r\nreceive guidance from nurses.


Muitas vezes, os cuidadores primários de pacientes crônicos se \r\ntornam o "paciente invisível", na medida em que a atenção e \r\nos cuidados são principalmente focados no doente, violando \r\naspectos físicos, emocionais, espirituais e econômicos do \r\ncuidador. Este projeto aborda os resultados obtidos na imple\r\n-\r\nmentação de um programa de intervenção educacional \r\nvoltado para 19 cuidadores primários de pessoas com doença \r\ncrónica, em seis delegações da cidade de Toluca, Estado do \r\nMéxico. O estudo era realizado em três etapas: diagnóstico, \r\nintervenção e avaliação. A fim de orientar sobre o programa \r\neducativo, foram realizadas visitas domiciliares, utilizando \r\no diário de campo. O programa consistiu de três módulos, \r\nconferindo-se oficinas aos 19 cuidadores, com prévio consen\r\n-\r\ntimento informado. Os cuidadores expressaram ter adquirido \r\nconhecimentos necessários para o cuidado de seu familiar \r\ne as dinâmica lhes permitiram reconhecer forças, fraquezas, \r\nmedos, inseguranças e frustrações. Eles disseram que estavam \r\nsatisfeitos com o apoio e orientação da equipe de saúde que \r\nparticipou. Pode-se dizer que ser o cuidador primário de um \r\npaciente crónico é uma experiência que transforma a vida e \r\nexige conhecimento, coragem e paciência para exercer as suas \r\nfunções com habilidade, podendo se aperfeiçoar se receber a \r\norientação de profissionais de enfermagem.


Assuntos
Enfermagem , Cuidadores , Educação
9.
Mar Pollut Bull ; 111(1-2): 95-105, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27449829

RESUMO

The effects exerted by metals in oysters are still a matter of debate and require more detailed studies. In this work we have investigated whether the health status of oysters are affected by the amount of metals present in the sediments of their habitat. Sediments and oysters were collected in the tidal part of the estuary of the Oka River (Basque Country), representative of other mesotidal, well mixed and short estuaries of the European Atlantic coast. The concentrations of 14 elements were determined in all the samples. Several biomarkers were also measured in the soft tissues of oysters. According to the concentrations found, the sediments were classified as non-toxic or slightly toxic. In good agreement, the histological alterations observed in oysters were not severe. Interestingly, in those sampling sites where the sediments showed relatively high metal concentrations, the metallic content in oysters was lower, and vice versa.


Assuntos
Sedimentos Geológicos/análise , Metais/análise , Ostreidae/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/análise , Ecotoxicologia/métodos , Monitoramento Ambiental , Estuários , Sedimentos Geológicos/química , Metalotioneína/metabolismo , Metais/farmacocinética , Metais/toxicidade , Ostreidae/fisiologia , Rios , Espanha , Poluentes Químicos da Água/análise
10.
J Environ Manage ; 161: 21-29, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26143082

RESUMO

As a consequence of the limited resources of underdeveloped countries and the limited interest of the developed ones, the assessment of the chemical quality of entire water bodies around the world is a utopia in the near future. The methodology described here may serve as a first approach for the fast identification of water bodies that do not meet the good chemical status demanded by the European Water Framework Directive (WFD). It also allows estimating the natural background (or reference values of concentration) of the areas under study using a simple criterion. The starting point is the calculation the World-Wide Natural Background Levels (WWNBLs) and World-Wide Threshold Values (WWTVs), two indexes that depend on the concentration of seven elements present in sediments. These elements, As, Cd, Cr, Cu, Ni, Pb and Zn, have been selected taking into account the recommendations of the UNEP (United Nations Environment Programme) and USEPA (United States Environmental Protection Agency), that describe them as elements of concern with respect to environmental toxicity. The methodology has been exemplified in a case study that includes 134 sediment samples collected in 11 transitional water bodies from 7 different countries and 4 different continents. Six of the water bodies considered met the good chemical status demanded by the WFD. The rest of them exceeded the reference WWTVs, at least for one of the elements. The estuaries of the Nerbioi-Ibaizabal (Basque Country) and Cavado (Portugal), the sea inlet of Río San Pedro (Spain), the Sepetiba Bay (Brazil) and the Yucateco lagoon (Mexico) belong to that group.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Brasil , Estuários , Hidrologia/métodos , Metais/análise , Metais/toxicidade , México , Portugal , Espanha , Estados Unidos , United States Environmental Protection Agency , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Qualidade da Água
11.
Environ Sci Pollut Res Int ; 21(21): 12518-29, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24946700

RESUMO

The relevance of a risk assessment of the built heritage was clearly justified due to the fact that it acts as a pollutant repository and hazardous pollutants have the capacity to penetrate into materials. However, the limitation of the sampling processes due to the high value of the built heritage makes a correct evaluation difficult. For that reason, in the present work, the potential of agar gels as non-invasive samplers of built heritage deterioration products, like crusts and patinas, was evaluated. Different gels of agar and Carbopol® (as control gel) were applied on these built surfaces considering several factors: the treatment time, the effectiveness of the addition of EDTA (ethylenediaminetetraacetic acid, C10H16N2O8) and its concentration and the use of a buffer at pH 7.5. All these factors were evaluated in order to determine the capacity of these gels as sampling systems under non-controlled atmospheric conditions. The results obtained in the assays were evaluated by visual examination, by evolution of pH and by the most important techniques used in the risk assessment analysis of the built heritage (Raman spectroscopy, scanning electron microscope (SEM)/energy dispersive X-ray (EDX) and inductively coupled plasma mass spectrometry (ICP-MS)). In this evaluation, the agar gels showed an intrinsic capacity as sampler with respect to the gel Carbopol® and thus, the best option between the studied gels consisted on agar gels with 2 % of EDTA and the longest application time. On the whole, the agar gels showed an interesting potential as non-invasive samplers of built heritage deterioration materials which should be studied more in depth.


Assuntos
Materiais de Construção/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Ágar/química , Ácido Edético/química , Géis , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Medição de Risco , Espectrometria por Raios X , Análise Espectral Raman
12.
Anal Bioanal Chem ; 399(9): 2949-59, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21057778

RESUMO

A multianalytical characterisation of black crusted modern construction materials from buildings located in the Bilbao Metropolitan area (North Spain) was carried out. According to the mineral composition determined by Raman spectroscopy, calcite and hematite were the major compounds found while aragonite, limonite, rutile, quartz and some aluminosilicates such as obsidian or amazonite (KAlSi(3)O(8)) were also present in minor percentages. As deterioration products, gypsum and anhydrite were widely found not only in the surface but also in the inner part of strongly deteriorated samples. Coquimbite (Fe(2)(SO(4))(3)·9H(2)O) was identified as well in the most protected facade where high amounts of Fe, having probably an anthropogenic origin, were measured by micro X-ray fluorescence (µ-XRF). Zn was found to be in high amounts while Cu, Pb, Ti, Mn, Sr and K were identified as minor elements. Considering the non-expected concentrations found for some anthropogenic elements, a sequential extraction was carried out in order to determine their chemical form by means of ion chromatography and inductively coupled plasma mass spectrometry. The orientation of the facades, which had a different influence from rain washing and industrial and traffic impact, was shown to affect the accumulation of different compounds in the black crust. Finally, the MEDUSA software was used to simulate the reactions among the original compounds, deposited pollutants and the atmospheric acid gases in order to explain the presence of the decaying species found.

13.
Arch Environ Contam Toxicol ; 59(2): 235-43, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20143053

RESUMO

From February 2004 to April 2006, the concentrations of more than 10 metals in mussels (Mytilus galloprovincialis) were measured in 10 stations from Galicia to the Basque Country in 8 different times of sampling. The mean highest concentrations are found for Zn [226.8 microg/g, dry weight (d.w.)] followed by Mn, As, Cu, and Co (between 10 and 25 microg/g d.w.). Lower mean concentrations are found for Se, Cr, Pb, V, and Ni (between 2 and 8 microg/g d.w.) and the lowest are for Cd, Sn, Hg, and Sb (between 0.05 and 1 microg/g d.w.). Among the statistical treatments used, the factor analysis showed a clustering of the mussels according to the geographical location. In addition, the temporal trend of the metal concentrations was studied by means of the Mann-Kendall test. In this sense, some stations showed a decreasing trend in the accumulation of the metallic content. However, there were some local pollution events that could be explained as a consequence of anthropogenic activities. Finally, the effects of the oil spill from the Prestige are discussed based on the experimental Ni/V ratio values obtained from this work and those of the original oil.


Assuntos
Monitoramento Ambiental , Metais/metabolismo , Mytilus/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Metais/análise , Análise Multivariada , Níquel/análise , Água do Mar/química , Espanha , Tempo , Vanádio/análise , Poluentes Químicos da Água/análise
14.
Bull Environ Contam Toxicol ; 83(2): 223-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19283326

RESUMO

The seasonal and spatial variability of trace metal concentrations of oyster tissues (Crassostea sps.) was studied. The samples were collected between 2002 and 2004 along the Urdaibai estuary (Murueta, Kanala and Arteaga). The seasonal influence on some metal concentrations (higher values in spring-summer season than in autumn-winter season) is more pronounced than the local site-specific influence. Furthermore, within each location a significant time-specific dependence on the trace metal concentration variations can be detected. Substantially higher concentrations of Zn (445.5-2,403.3 mg kg(-1)) and Mn (29.4-169.6 mg kg(-1)) were recorded in oysters inhabiting estuarine locations, possibly indicating a markedly higher natural bioavailability at these locations. Principal component analysis demonstrated that oysters could be separated depending on the inhabiting areas: Sn for Murueta, essential metals for Kanala, and Co and Cd for Arteaga sampling points, respectively.


Assuntos
Crassostrea/metabolismo , Monitoramento Ambiental , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Geografia , Metabolismo dos Lipídeos , Análise de Componente Principal , Rios/química , Espanha , Fatores de Tempo
15.
Anal Chim Acta ; 622(1-2): 126-32, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18602543

RESUMO

In order to estimate the bioaccessibility of metals from mussel tissues, an in vitro physiologically based extraction test was applied to simulate the human gastrointestinal conditions. The samples were subjected to human body temperature, and Ag, Co, Cr, Cu, Mn, Ni, Pb and Sn were sequentially extracted with simulated gastric solution, followed by extraction with a simulated intestinal solution. Both gastric and intestinal extracted solutions and microwave-digested residue were analysed by ICP-MS. The procedure was applied to a certified reference material NIST 2977 (mussel tissue) to prove the accuracy of the method. Some mussel tissue samples from Northern Spain were subjected to this procedure to determine their metal content and their metal oral bioaccessibility.


Assuntos
Bivalves/química , Absorção Intestinal/fisiologia , Metais/análise , Metais/toxicidade , Modelos Biológicos , Animais , Temperatura Corporal , Ácido Gástrico/química , Humanos , Espectrometria de Massas , Micro-Ondas , Espanha , Fatores de Tempo , Extratos de Tecidos/análise , Extratos de Tecidos/química
16.
Lupus ; 17(7): 676-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18625641

RESUMO

Adalimumab, an anti-tumour necrosis factor agent, especially used in the treatment of rheumatoid arthritis, has a good safety profile. One of the most common side-effects of adalimumab is the development of autoantibodies. Despite the induction of autoantibodies, the clinical presentation of immune-mediated complications upon adalimumab therapy, including a lupus-like syndrome, is very rare. We have recently evaluated a new case of adalimumab-induced lupus erythematosus.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Lúpus Eritematoso Sistêmico/induzido quimicamente , Adalimumab , Anticorpos Monoclonais Humanizados , Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Pessoa de Meia-Idade , Pele/patologia
17.
J Mol Endocrinol ; 41(1): 35-44, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18487229

RESUMO

Pancreatic beta-cell homeostasis is a balance between programmed cell death (apoptosis) and regeneration. Although autoimmune diabetes mellitus type 1 (DM1) is the most-studied cause of beta-cell mass loss by pro-inflammatory cytokine-induced apoptosis, influences of a pro-inflammatory environment on beta-cell regenerative response have been poorly studied. In this study, we assess the anti-proliferative effect of pro-inflammatory cytokines and glucose concentration on rat pancreatic beta cells and the potential protective role of glucagon-like peptide (GLP-1). Apoptotic and proliferating islet cells were stained using the DeadEnd Fluorimetric TUNEL System and 5-bromo-2'-deoxyuridine label respectively, in the presence-absence of varying concentrations of glucose, pro-inflammatory cytokines, and GLP-1. The potential signaling pathways involved were evaluated by western blot. Considerable anti-proliferative effects of pro-inflammatory cytokines interleukin (IL)-1beta, interferon (IFN)-gamma, and tumour necrosis factor-alpha (TNF-alpha) were observed. The effects were synergistic and independent of glucose concentration, and appeared to be mediated by the inhibition of extracellular signal-regulated kinase 1/2 (ERK1/2) activation, the signaling pathway involved in beta-cell replication. GLP-1 completely reversed the cytokine-induced inhibition of ERK phosphorylation and increased beta-cell proliferation threefold in cytokine-treated cultures. While pro-inflammatory cytokines reduced islet cell ERK1/2 activation and beta-cell proliferation in pancreatic islet culture, GLP-1 was capable of reversing this effect. These data suggest a possible pharmacological application of GLP-1 in the treatment of early stage DM1, to prevent the loss of pancreatic beta cells as well as to delay the development of overt diabetes.


Assuntos
Proliferação de Células , Citocinas/fisiologia , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Mediadores da Inflamação/fisiologia , Células Secretoras de Insulina/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Animais , Técnicas de Cultura de Células , Células Cultivadas , Glucose/fisiologia , Células Secretoras de Insulina/enzimologia , Masculino , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/fisiologia , Ratos , Ratos Wistar
18.
Anal Bioanal Chem ; 391(4): 1361-70, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18265964

RESUMO

Nitrate salts have become of greater importance in the decay of materials from historical buildings due to changes in the environment. This work presents an analytical diagnosis methodology to evaluate the impact of nitrate salts in mortars and bricks, combining noninvasive and microdestructive analytical techniques together with chemometric and thermodynamic data analyses. The impact of nitrate salts cannot be well ascertained if other soluble salts are not taken into account. Therefore, the principal results from this work relate to nitrate salts but some results for other kinds of salts are included. Data from Raman microprobe spectroscopy and micro X-ray fluorescence (micro-XRF) are used to characterise the original composition and a first approximation of the nature of the decay compounds, mainly nitrates. The soluble salts are extracted and the anions and cations are quantified by means of ion chromatography with conductimetric detection for anions/cations and inductively coupled plasma mass spectrometry (ICP/MS) for cations. The values obtained allow two different data treatments to be applied. First, chemometric analysis is carried out to search for correlations among anions and cations. Second, thermodynamic modelling with the RUNSALT program is performed to search for environmental conditions of soluble salt formation. All the results are finally used to diagnose the impact of nitrates.

19.
Anal Bioanal Chem ; 389(5): 1603-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17786410

RESUMO

The on-fibre derivatisation of volatile fatty acids (VFAs) using N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA) was optimised in the simultaneous determination of VFAs together with phenols and indoles by headspace solid-phase microextraction (SPME)-gas chromatography-mass spectrometry. Firstly, the nature of the SPME fibre was optimised and four different fibres were studied (100 microm polydimethylsiloxane, 85 microm Carboxen/polydimethylsiloxane, 5/30 microm divinylbenzene/Carboxen/polydimethylsiloxane and 85 microm polyacrylate). The optimum fibre (50/30 microm divinylbenzene/Carboxen/polydimethylsiloxane) was used to study the exposure time of the fibre to the derivatisation agent and the desorption time and temperature. Firstly, a factorial design was built but since the three variables had a significant effect, a central composite design was used to build the response surfaces. The best signals were obtained after the exposure of the fibre in the headspace of the MTBSTFA derivatisation reagent for 1 h and desorption at 300 degrees C for 9 min. The determination of underivatised phenols and indoles was not affected by the presence of the derivatisation reagent in the fibre.


Assuntos
Ácidos Graxos/análise , Indóis/análise , Fenóis/análise , Animais , Bovinos , Cromatografia Gasosa , Espectrometria de Massas
20.
J Chromatogr A ; 1136(1): 1-9, 2006 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-17049541

RESUMO

The headspace solid-phase microextraction (HS-SPME) of some odorous organic compounds [volatile fatty acids (VFAs), phenols and indoles] from animal wastes was optimised using an experimental design approach. The variables affecting the HS-SPME process studied were as follows: type of fibre, pH of the slurry (3-7), addition of sodium chloride (0-1 mol L(-1)), sample volume (10-30 mL), exposure time (10-30 min), exposure temperature (25-50 degrees C), desorption time (3-10 min) and desorption temperature (230-310 degrees C). As for the sorbent, three different types of fibres were studied: 50/30 microm divinylbenzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS), 100 microm PDMS and 85 microm CAR/PDMS. Methylation VFAs was observed when fibres containing PDMS were used. The analytes studied in the optimisation procedure were acetic acid, propanoic acid, butanoic acid, 3-methylbutanoic acid, pentanoic acid, phenol, 4-methylphenol, 4-ethylphenol, indole and skatole (3-methylindole). In order to study the influence of the variables on the responses of the compounds, a Plackett-Burman design was built using the Unscrambler program. The optimisation was carried out using real samples. In order to take into account the matrix effect on the calibration curves, standard solutions were prepared using a purged cow slurry free from the analytes of interest. Repeatability within and among days, accuracy and detection limits were calculated from these calibration curves.


Assuntos
Fezes/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos/análise , Urina/química , Animais , Calibragem , Bovinos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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