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1.
Aquat Toxicol ; 244: 106095, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35121565

RESUMO

The primary focus of environmental toxicological studies is to address the direct effects of chemicals on exposed organisms (parental generation - F0), mostly overlooking effects on subsequent non-exposed generations (F1 and F2 - intergenerational and F3 transgenerational, respectively). Here, we addressed the effects of simvastatin (SIM), one of the most widely prescribed human pharmaceuticals for the primary treatment of hypercholesterolemia, using the keystone crustacean Gammarus locusta. We demonstrate that SIM, at environmentally relevant concentrations, has significant inter and transgenerational (F1 and F3) effects in key signaling pathways involved in crustaceans' neuroendocrine regulation (Ecdysteroids, Catecholamines, NO/cGMP/PKG, GABAergic and Cholinergic signaling pathways), concomitantly with changes in apical endpoints, such as depressed reproduction and growth. These findings are an essential step to improve hazard and risk assessment of biological active compounds, such as SIM, and highlight the importance of studying the transgenerational effects of environmental chemicals in animals' neuroendocrine regulation.


Assuntos
Anfípodes , Poluentes Químicos da Água , Animais , Reprodução , Sinvastatina/toxicidade , Poluentes Químicos da Água/toxicidade
2.
Sci Total Environ ; 805: 150384, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818755

RESUMO

The bioaccumulation and depuration of seven organophosphorus flame retardants (OPFRs) in marine mussel Mytilus galloprovincialis were studied. OPFRs showed to be bioavailable in aquatic environments. When mussels are exposed to environmentally relevant concentrations of OPFRs, uptake kinetics fit well to a first-order model with a single compartment; in contrast depuration rates were generally underestimated by that model, most likely because it does not take into account the biotransformation of OPFRs by the organisms. The highest bioaccumulation rates were observed for tricresyl phosphate (TCrP), triphenyl phosphate (TPhP) and 2-ethylhexyldiphenylphosphate (EHDPP). This could be due to the presence of aryl groups in these compounds, their low solubility in water, and their affinity for fat tissues. According to these findings TCrP, with a BCF value of 4042 L kg-1 wet weight, should be classified in environmental regulations as an accumulative chemical.


Assuntos
Retardadores de Chama , Mytilus , Animais , Bioacumulação , Cinética , Organofosfatos , Compostos Organofosforados
3.
Sci Total Environ ; 767: 144976, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636779

RESUMO

Plastics accumulation in marine ecosystems has notable ecological implications due to their long persistence, potential ecotoxicity, and ability to adsorb other pollutants or act as vectors of pathogens. The present work aimed to evaluate the physiological response of the gilthead seabream (Sparus aurata) fed for 90 days with a diet enriched with virgin and seawater exposed low-density polyethylene microplastics (LDPE-MPs) (size between 100 and 500 µM), followed by 30 days of depuration, applying oxidative stress and inflammatory markers in liver homogenates. No effects of LDPE-MPs treatments on fish growth were observed throughout this study. A progressive increase in antioxidant enzyme activities was observed throughout the study in both treatments, although this increase was higher in the group treated with seawater exposed MPs. This increase was significantly higher in catalase (CAT), glutathione reductase (GRd), and glutathione-s-transferase (GST) in the seawater exposed MPs group, with respect to the virgin group. In contrast, no significant differences were recorded in superoxide dismutase (SOD) and glutathione peroxidase (GPx) between both groups. Exposure to MPs also caused an increase in the oxidative damage markers (malondialdehyde and carbonyls groups). Myeloperoxidase activity significantly increased because of MPs treatments. After 30 days of depuration, antioxidant, inflammatory enzyme activities and oxidative damage markers returned to values similar to those observed in the control group. In conclusion, MPs exposure induced an increase of antioxidant defences in the liver of S. aurata. However, these elevated antioxidant capabilities were not enough to prevent oxidative damage in the liver since, an increased oxidative damage marker was associated with MPs ingestion. The treatment with seawater exposed MPs caused a more significant antioxidant response (CAT, GRs, and GST). Although after a depuration period of 30 days a tendency to recover the initial values of the biomarkers was observed this does not seem to be time enough for a complete normalization.


Assuntos
Dourada , Poluentes Químicos da Água , Animais , Catalase/metabolismo , Dieta , Ecossistema , Inflamação , Fígado/química , Microplásticos , Estresse Oxidativo , Plásticos/metabolismo , Plásticos/toxicidade , Dourada/metabolismo , Água do Mar , Poluentes Químicos da Água/análise
4.
Environ Int ; 144: 106020, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32861161

RESUMO

The hypothesis that exposure to certain environmental chemicals during early life stages may disrupt reproduction across multiple non-exposed generations has significant implications for understanding disease etiology and adverse outcomes. We demonstrate here reproductive multi and transgenerational effects, at environmentally relevant levels, of one of the most prescribed human pharmaceuticals, simvastatin, in a keystone species, the amphipod Gammarus locusta. The transgenerational findings has major implications for hazard and risk assessment of pharmaceuticals and other contaminants of emerging concern given that transgenerational effects of environmental chemicals are not addressed in current hazard and risk assessment schemes. Considering that the mevalonate synthesis, one of the key metabolic pathways targeted by simvastatin, is highly conserved among metazoans, these results may also shed light on the potential transgenerational effects of simvastatin on other animals, including humans.


Assuntos
Anfípodes , Sinvastatina , Animais , Epigênese Genética , Humanos , Reprodução , Sinvastatina/toxicidade
5.
Rev. esp. drogodepend ; 45(2): 91-103, abr.-jun. 2020. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-198761

RESUMO

El análisis de aguas residuales con fines epidemiológicos es actualmente una herramienta fiable y complementaria a las metodologías basadas en indicadores tradicionales para el control de diferentes sustancias entre las que cabe destacar las drogas. Si bien varios países europeos la utilizan como herramienta de trabajo para la monitorización de drogas de abuso, en España su uso se limita principalmente a estudios realizados por diferentes grupos de investigación, tal y como se describe en el caso práctico puesto de ejemplo en el artículo. Sin embargo, el potencial de la metodología ha quedado evidenciado en los estudios científicos llevados a cabo tanto a nivel español como internacional y, aunque son necesarios más estudios para llegar a conocer todo su potencial, se prevé pueda ser incorporada como herramienta de trabajo complementaria a las que habitualmente se utilizan. En este sentido, la Red Española de Análisis de Aguas Residuales (ESAR-Net), creada en 2017 y formada por diferentes grupos de investigación españoles, pretende contribuir al conocimiento y aplicación de esta metodología en España a través de actividades científicas y de divulgación


Wastewater-Based Epidemiology is currently a reliable and complementary tool to methodologies based on traditional indicators for the control of various substances such as drugs. Although several European countries use it as a working tool for the monitoring of drugs of abuse, in Spain its use is mainly limited to studies carried out by different research groups, as described in the case study used as an example in the article. However, the potential of the methodology has been demonstrated in the scientific studies carried out both at the Spanish and international level and, although more studies are necessary to get to know its full potential, it is expected that it could be incorporated as a complementary work tool to those that are usually used. In this sense, the Red Española de Análisis de Aguas Residuales (ESAR-Net), created in 2017 and formed by different Spanish research groups, aims to contribute to the knowledge and application of this methodology in Spain through scientific and outreach activities


Assuntos
Humanos , Monitoramento Ambiental , Águas Residuárias/química , Drogas Ilícitas/análise , Detecção do Abuso de Substâncias/métodos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Águas Residuárias/análise , Drogas Ilícitas/classificação , Espanha
6.
Arch Environ Contam Toxicol ; 72(4): 606-611, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28391487

RESUMO

The growing concern regarding the negative effects of solar radiation on the skin has led to a drastic increase in the use of sunscreens containing in its composition up to 10% of aromatic chemicals, such as ethylhexyl dimethyl p-aminobenzoic acid (OD-PABA) and octocrylene (OC). The objective of this study was to evaluate the toxicity and to assess the environmental risk posed by these two ultraviolet filters, widely used in cosmetics and as plastic additives, in the marine environment. Several ecotoxicological bioassays were performed with three model organisms belonging to different trophic levels: the microalgae Isochrysis galbana, the mussel Mytilus galloprovincialis, and the sea urchin Paracentrotus lividus. The results show remarkable toxicity to marine species for both OD-PABA (EC10 values range 26,5-127 µg L-1) and OC (EC10 range 103-511 µg L-1). The cell division in the microalgae I. galbana was the most sensitive endpoint tested. To determine the environmental risk of these substances, the risk coefficient (RQ) was calculated. Due to the higher concentrations reported, OC showed remarkable risk (RQ = 0.27), whereas for OD-PABA the risk was low (RQ = 0.007).


Assuntos
Acrilatos/toxicidade , Organismos Aquáticos/fisiologia , Protetores Solares/toxicidade , Testes de Toxicidade/métodos , Poluentes Químicos da Água/toxicidade , para-Aminobenzoatos/toxicidade , Animais , Monitoramento Ambiental , Haptófitas , Mytilus , Paracentrotus , Medição de Risco
7.
Environ Sci Pollut Res Int ; 23(4): 3847-59, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26498966

RESUMO

The uptake of polybrominated diphenyl ethers (PBDEs) by carrot and lettuce was investigated. Degradation of PBDEs in soil in the absence of the plants was discarded. Different carrot (Nantesa and Chantenay) and lettuce (Batavia Golden Spring and Summer Queen) varieties were grown in fortified or contaminated compost-amended soil mixtures under greenhouse conditions. After plant harvesting, roots (core and peel) and leaves were analyzed separately for carrot, while for lettuce, leaves and hearts were analyzed together. The corresponding bioconcentration factors (BCFs) were calculated. In carrots, a concentration gradient of 2,2',3,4,4',5'-hexabromodiphenyl ether (BDE-138) became evident that decreased from the root peel via root core to the leaves. For decabromodiphenyl ether (BDE-209) at the low concentration level (7 and 20 ng g(-1)), the leaves incorporated the highest concentration of the target substance. For lettuce, a decrease in the BCF value (from 0.24 to 0.02) was observed the higher the octanol-water partition coefficient, except in the case of BDE-183 (BCF = 0.51) and BDE-209 (BCF values from 0.41 to 0.74). Significant influence of the soils and crop varieties on the uptake could not be supported. Metabolic debromination, hydroxylation or methylation of the target PBDEs in the soil-plant system was not observed.


Assuntos
Daucus carota/metabolismo , Éteres Difenil Halogenados/metabolismo , Poluentes do Solo/metabolismo , Solo , Produtos Agrícolas/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo
8.
J Chromatogr A ; 1360: 57-65, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25130091

RESUMO

In the present work, a novel analytical method for the simultaneous determination of ten polybrominated diphenyl ethers (PBDEs), eight methoxylated PBDEs (MeO-PBDEs) and seven hydroxylated PBDEs (OH-PBDEs) in soil, lettuce and carrot samples was developed. The procedure was based on matrix solid-phase dispersion (MSPD) followed by gas chromatography coupled to negative chemical ionization-mass spectrometry (GC-NCI-MS). Under optimum conditions, 0.5g of sample (freeze-dried in the case of lettuce and carrot samples) was dispersed with 0.5g of octadecyl-functionalized silica (C18) and 1.75g of acidified silica (10% H2SO4, w/w) was used as clean-up sorbent. A two-step fractionated elution was carried out. First, PBDEs and MeO-PBDEs were eluted in 75:25% (v/v) n-hexane/dichloromethane mixture and, then, the retained OH-PBDEs were eluted in pure dichloromethane. Both extracts were analyzed by GC-NCI-MS separately, in the case of OH-PBDEs after derivatization with N-methyl-N-(trimethylsilyl) trifluoroacetamide. The developed method was validated in terms of accuracy for soil, lettuce and carrot matrices, spiked at two fortification levels (5 and 25ngg(-1)). After correction with the corresponding surrogate, apparent recovery values (defined as the recovery obtained after correction with the corresponding surrogate) were in the 80-129% range. Precision (as relative standard deviation) in the 1-21% range and method detection limits (MDLs) in the 0.003 and 0.3ngg(-1) range for soil and in the 0.003-0.4ngg(-1) range (dry weight) for lettuce and carrot samples were obtained. For PBDEs the method was also validated with a standard reference material (SRM-2585) of house dust. Finally, the method was applied for the determination of target analytes in soil, lettuce and carrot.


Assuntos
Daucus carota/química , Éteres Difenil Halogenados/análise , Solo/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Éteres Difenil Halogenados/química , Hidroxilação , Limite de Detecção
9.
J Chromatogr A ; 1356: 163-70, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25001332

RESUMO

Membrane-assisted solvent extraction (MASE) coupled to liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) was studied for the determination of a variety of emerging and priority compounds in wastewater. Among the target analytes studied certain hormones (estrone (E1), 17ß-estradiol (E2), androsterone (ADT), 17α-ethynyl estradiol (EE2), diethylstilbestrol (DES), equilin (EQ), testosterone (TT), mestranol (MeEE2), 19-norethisterone (NT), progesterone (PG) and equilenin (EQN)), alkylphenols (APs) (4-tert-octylphenol (4tOP), nonylphenol technical mixture (NPs) and 4n-octylphenol (4nOP)) and BPA were included. The work was primarily focused in the LC-MS/MS detection step, both in terms of variable optimization and with respect to the matrix effect study. Both, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) were assessed both in the negative and positive mode, including the optimization of MS/MS operating conditions. The best results were obtained, in most of the cases, for ESI using 0.05% ammonium hydroxide as buffer solution in the mobile phase, composed with methanol and water. Under optimum detection conditions, matrix effect during the detection step was thoroughly studied. Dilution, correction with deuterated analogues and clean-up of the extracts were evaluated for matrix effect correction. Clean-up with Florisil together with correction with deuterated analogues provided the most satisfactory results, with apparent recoveries in the 57-136% range and method detection limits in the low ngL(-1) level for most of the analytes. For further validation of the method, two separated extraction procedures, the above mentioned MASE, and conventional solid phase extraction (SPE) were compared during the analysis of real samples and comparable results were successfully obtained for E1, E2, EE2, DES, NT, TT, EQ, PG, BPA, ADT, 4nOP, 4tOP, NPs and EQN.


Assuntos
Disruptores Endócrinos/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Androstanos/análise , Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão , Dietilestilbestrol/análise , Estrenos/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Extração Líquido-Líquido , Fenóis/análise , Extração em Fase Sólida , Solventes/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
10.
Chemosphere ; 104: 44-50, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24359924

RESUMO

Due to the concern about the negative effects of exposure to sunlight, combinations of UV filters like 4-Methylbenzylidene-camphor (4-MBC), Benzophenone-3 (BP-3), Benzophenone-4 (BP-4) and 2-Ethylhexyl-4-methoxycinnamate (EHMC) are being introduced in all kind of cosmetic formulas. These chemicals are acquiring a concerning status due to their increasingly common use and the potential risk for the environment. The aim of this study is to assess the behaviour of these compounds in seawater, the toxicity to marine organisms from three trophic levels including autotrophs (Isochrysis galbana), herbivores (Mytilus galloprovincialis and Paracentrotus lividus) and carnivores (Siriella armata), and set a preliminary assessment of potential ecological risk of UV filters in coastal ecosystems. In general, EC50 results show that both EHMC and 4-MBC are the most toxic for our test species, followed by BP-3 and finally BP-4. The most affected species by the presence of these UV filters are the microalgae I. galbana, which showed toxicity thresholds in the range of µg L(-1) units, followed by S. armata>P. Lividus>M. galloprovincialis. The UV filter concentrations measured in the sampled beach water were in the range of tens or even hundreds of ng L(-1). The resulting risk quotients showed appreciable environmental risk in coastal environments for BP-3 and 4-MBC.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Benzofenonas/toxicidade , Cânfora/análogos & derivados , Cânfora/toxicidade , Cinamatos/toxicidade , Crustáceos/efeitos dos fármacos , Ecotoxicologia , Haptófitas/efeitos dos fármacos , Mytilus/efeitos dos fármacos , Paracentrotus/efeitos dos fármacos , Água do Mar/análise
11.
J Chromatogr A ; 1287: 2-22, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-22901328

RESUMO

The computer-assisted development of separation procedures in liquid chromatography (LC), which has involved the adaptation of diverse chemometric techniques and the incorporation of successive advances in informatics and computing over a period of more than four decades, has provided chromatographers with commercial and academic tools of great utility. These tools enable the development, optimization (including robustness studies) and transfer of procedures that constitute one of the analytical activities most commonly used at present in laboratories and industries worldwide. Departing from a typical operational scheme of manually developed chromatographic procedures, this review describes some of the different tools and options that chemometrics provides to the chromatographer for the computer-assisted approach, and outlines the present status of this approach and possible reasons why it is still not considered fully satisfactory.


Assuntos
Cromatografia de Fase Reversa/métodos , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador
12.
Anal Chim Acta ; 743: 101-10, 2012 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-22882829

RESUMO

The stability of the UV filter benzophenone-4 (BP-4) in free chlorine-containing water was investigated, for the first time, by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QqTOF-MS). High mass accuracy and resolution capabilities of this hybrid mass spectrometer were used for the reliable assignation of empirical formulae and chemical structures of BP-4 derivatives. Time-course profiles of the parent compound and its by-products were simultaneously recorded by direct injection of sample aliquots, after quenching the excess of chlorine, in the LC-QqTOF-MS system. At neutral pHs, in excess of chlorine, BP-4 showed a limited stability fitting a pseudo-first-order degradation kinetics. A noticeable reduction in the half-lives of BP-4 was observed when increasing the sample pH between 6 and 8 units and also in presence of bromide traces. The reaction pathway of this UV filter involved a first electrophilic substitution of hydrogen per chlorine (or bromide) in the phenolic ring, followed by oxidation of the carbonyl moiety to an ester group, which induced a further electrophilic substitution in the same aromatic ring. Above reactions were also noticed when mixing a BP-4 containing personal care product with chlorinated tap water and in chlorinated swimming pool and sewage water, previously spiked with a BP-4 standard.


Assuntos
Benzofenonas/química , Técnicas de Química Analítica , Cloro/química , Cromatografia Líquida , Espectrometria de Massas , Concentração de Íons de Hidrogênio
13.
Int J Clin Pract ; 66(3): 305-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22340450

RESUMO

INTRODUCTION: To evaluate the efficacy of Daptomycin (DPT) lock therapy in the treatment of Grampositive long-term catheter-related bloodstream infections (LT-CRBI). PATIENTS AND METHODS: A retrospective review of all patients receiving DPT lock therapy for the treatment of LT-CRBI from December 2009 to May 2010 was conducted. The primary endpoint used in this study was failure to cure the episode of LT-CRBI. Cure was defined as fever disappearance, negative blood cultures within 1 month after the end of treatment, and catheter salvage. RESULTS: Thirteen subjects (seven men, mean age 62 years) were evaluated. There were six Staphylococcus epidermidis, two Staphylococcus hominis, one Staphylococcus haemolyticus, two Enterococcus faecalis and two polymicrobial (S. epidermidis and S. hominis) bloodstream infections. DPT lock therapy was administered for a mean of 14 days (interquartilic range 10-14). Intravenous DPT was administered in nine patients for a mean of 10 days (interquartilic range 5-11). Clinical cure and blood culture sterilisation occurred in 11 of 13 patients (85%). Two patients had fever during treatment and catheters were removed. Median length of follow-up in patients with therapeutic success was 67 days (interquartilic range 14-88). CONCLUSION: DPT lock therapy demonstrated good in vivo efficacy in LT-CRBI caused by coagulase negative staphylococci and Enterococcus species.


Assuntos
Antibacterianos/administração & dosagem , Bacteriemia/tratamento farmacológico , Infecções Relacionadas a Cateter/tratamento farmacológico , Cateteres de Demora/efeitos adversos , Daptomicina/administração & dosagem , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Idoso , Infecções Relacionadas a Cateter/prevenção & controle , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
J Chromatogr A ; 1217(16): 2642-66, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20083248

RESUMO

Introduced in 1999 as a novel solventless sample preparation method, stir-bar sorptive extraction (SBSE) has become a popular analytical technique for the pre-concentration of organic compounds into a polydimethylsiloxane (PDMS)-coated stir-bar. In the last 10 years, hundreds of applications in the environmental, food and biomedical fields can be found in the literature. However, only PDMS-coated stir-bars are commercially available, which reduces the applicability of SBSE to the extraction of the non-polar compounds due to the poor extractability of more polar analytes. In this review, a view on method optimisation, limitations, potential solutions such as in-house coatings and derivatisation and novel applications in multi-residue analysis and passive sampling are revised.


Assuntos
Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Compostos Orgânicos/química
15.
Talanta ; 76(3): 580-90, 2008 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-18585324

RESUMO

Comparability of monitoring data are essential for any meaningful assessment and for the management of environmental risks of emerging pollutants. The reliability and comparability of data at European level is often limited, because analytical methods for emerging pollutants are often not fully validated, not harmonized or not suitable for all relevant matrices. This paper describes a collaborative interlaboratory exercise for the analysis of non-steroidal anti-inflammatory drugs (NSAIDs) residues in freshwater and wastewater, held in the framework of the EU project "Network of reference laboratories for monitoring of emerging environmental pollutants" (NORMAN). The NSAID compounds selected in this study were ketoprofen, naproxen, ibuprofen and diclofenac. Thirteen laboratories distributed along nine European Countries (Austria, France, Germany, Greece, Italy, Slovak Republic, Slovenia, Spain, and Switzerland) took part in this exercise, 126 samples were analyzed and a total number of 473 values in duplicate were collected. Samples selected in this study include environmental water (river water and waste water) and artificial water (fortified environmental and distilled water) with different ranges of complexity. Two analytical methods were proposed by the organiser; one is based on the use of solid phase extraction (SPE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the second one is based on SPE followed by gas-chromatography-mass spectrometry (GC-MS), however, in the first round some different approaches were also admitted. The main goals of this interlaboratory comparison were to evaluate the available analytical schemes for NSAID analysis in natural waters, to evaluate the repeatability (r) and reproducibility (R) between participating laboratories, and to evaluate the influence of the analytical method and sample matrices on the results.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Cromatografia Gasosa-Espectrometria de Massas/normas , Espectrometria de Massas em Tandem/normas , Poluentes Químicos da Água/análise , Cromatografia Líquida , Europa (Continente) , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Extração em Fase Sólida
16.
Chemosphere ; 67(7): 1453-62, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17123577

RESUMO

A useful tool based on a single-step extraction and clean-up procedure for the determination of 15 organohalogenated pollutants (including brominated flame retardants) in aquaculture samples, using aluminium oxide basic and acidic silica gel in the supercritical extraction cell followed by gas chromatography with electron capture detection or mass spectrometry has been developed. This effective clean-up step ensures a minimum of chromatographic difficulties related to complex matrix components such as aquaculture feed. The extraction procedure has been screened by a fractional factorial design for the preliminary statistically significant parameters. The factors selected were extraction temperature, pressure, static extraction time, dynamic extraction time and carbon dioxide flow rate. The Doehlert design, followed by a multicriteria decision-making strategy, was then performed in order to determine the optimum conditions for the two most significant factors: pressure (165 bar) and dynamic extraction time (27 min). Under optimal conditions, the procedure developed with GC-MS/MS provides an excellent linearity, detection (0.01-0.2 ng g(-1)) and quantification limits (0.05-0.8 ng g(-1)) for most of the analytes investigated. The feasibility of the proposed supercritical fluid extraction method was validated by analysing two reference materials and fish feed and shellfish samples with satisfactory results.


Assuntos
Aquicultura , Hidrocarbonetos Halogenados/análise , Poluentes Químicos da Água/análise , Ração Animal/análise , Animais , Cromatografia Gasosa , Cromatografia com Fluido Supercrítico , DDT/análogos & derivados , DDT/análise , Eletroquímica , Peixes/fisiologia , Retardadores de Chama/análise , Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/análise , Bifenilos Policlorados/análise , Espanha
17.
An Sist Sanit Navar ; 29 Suppl 2: 105-12, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-16998519

RESUMO

A lung transplant is usually the final therapeutic option for patients with respiratory insufficiency. In spite of the many advances in immunology and the management of complications, mortality and morbidity associated with this transplant are far higher than with others. Acute rejection is an almost universal problem in the first year, while obliterative bronchitis reduces long term survival. Respiratory infections also play a significant role in the complications associated with lung transplants due to the constant exposure of the graft to the outside. However, the success of this therapeutic option, which basically depends on a suitable selection of donor and recipient, are evident, above all with respect to quality of life.


Assuntos
Transplante de Pulmão , Doença Aguda , Fatores Etários , Idoso , Bronquiolite Obliterante/etiologia , Contraindicações , Seleção do Doador , Seguimentos , Rejeição de Enxerto/etiologia , Transplante de Coração-Pulmão , Humanos , Doadores Vivos , Transplante de Pulmão/métodos , Transplante de Pulmão/mortalidade , Pessoa de Meia-Idade , Seleção de Pacientes , Cuidados Pós-Operatórios , Complicações Pós-Operatórias , Prognóstico , Doença Pulmonar Obstrutiva Crônica/cirurgia , Fibrose Pulmonar/cirurgia , Qualidade de Vida , Insuficiência Respiratória/cirurgia , Fatores de Tempo
18.
An. sist. sanit. Navar ; 29(supl.2): 105-112, mayo-ago. 2006.
Artigo em Es | IBECS | ID: ibc-052128

RESUMO

El tranplante pulmonar suele ser la última opción terapéutica para pacientes con insuficiencia respiratoria. A pesar de los muchos avances en inmunología y el manejo de las complicaciones, la mortalidad y morbilidad asociadas a este trasplante son muy superiores a los demás. El rechazo agudo es casi un problema universal en el primer año, mientras que la bronquiolitis obliterante limita la supervivencia a largo plazo. Las infecciones respiratorias también cumplen un papel importante en las complicaciones asociadas al trasplante pulmonar por la constante exposición del injerto al medio exterior. No obstante, los éxitos de esta opción terapéutica que depende fundamentalmente de una correcta selección de donante y receptor, son evidentes, sobre todo en cuanto a calidad de vida se refiere


A lung transplant is usually the final therapeutic option for patients with respiratory insufficiency. In spite of the many advances in immunology and the management of complications, mortality and morbidity associated with this transplant are far higher than with others. Acute rejection is an almost universal problem in the first year, while obliterative bronchitis reduces long term survival. Respiratory infections also play a significant role in the complications associated with lung transplants due to the constant exposure of the graft to the outside. However, the success of this therapeutic option, which basically depends on a suitable selection of donor and recipient,are evident, above all with respect to quality of life


Assuntos
Humanos , Insuficiência Respiratória/cirurgia , Transplante de Pulmão/métodos , Rejeição de Enxerto/epidemiologia , Bronquiolite Obliterante/complicações , Complicações Pós-Operatórias , Seleção de Pacientes , Qualidade de Vida , Doadores de Tecidos/classificação , Condicionamento Pré-Transplante/métodos , Anastomose Cirúrgica/efeitos adversos , Complicações Pós-Operatórias/diagnóstico
19.
J Chromatogr A ; 1108(2): 158-65, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16442119

RESUMO

The feasibility of solid-phase microextraction (SPME) for the determination of several organophosphorus flame retardants and plastizicers in water samples by gas chromatography-nitrogen phosphorous detection (GC-NPD) is evaluated. These compounds have a wide range of polarities and volatilities and require a thorough optimisation of the different SPME parameters. Considering also possible contamination and carryover sources, the best compromise microextraction conditions were found to be direct extraction of 22 ml samples, containing 300 mg/ml of NaCl, with a PDMS-DVB coated fibre at room temperature. Although equilibrium was not achieved, an extraction time of 40 min allowed obtaining a good sensitivity (quantification limits between 0.010 and 0.025 ng/ml), comparable to that achieved by solid-phase extraction (SPE) of 1l samples, producing both similar values of precision and accuracy. Furthermore, the SPME method has shown to be free of matrix effects, avoiding the need of employing the standard addition procedure for quantification, and was suitable for the determination of eight of the nine considered compounds. Only tris-(2-ethylhexyl)-phosphate was neither determinable by SPME nor by SPE. Finally, the application of the developed methodology to the analysis of wastewater samples, showed that important concentrations of these compounds (up to 10 ng/ml) have been detected in treated sewage water, being discharged into the aquatic environment.


Assuntos
Retardadores de Chama/análise , Compostos Organofosforados/análise , Plastificantes/análise , Cromatografia Gasosa
20.
J Chromatogr A ; 1071(1-2): 93-8, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15865179

RESUMO

An effective multiresidual method for the trace analysis of fifteen compounds from a diverse group of pesticides, polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyl (PCBs) and polybrominated biphenyl (PBBs) in aquaculture feed is described. The analytical procedure is based on the matrix solid-phase dispersion (MSPD) of feed sample and subsequent elution with hexane. The MSPD process was evaluated using an asymmetrical experimental design 2(3)3(2)//9. Factors such as C18 sorbent amount, kind of adsorbents, solvent volume and elution mode were considered. The results suggest that the operational MSPD conditions are elution with pressure, 1 g of C18, basic alumina as adsorbent and 30 mL of hexane. The overall method including MSPD procedure and GC coupled to mass spectrometry (MS/MS) has been applied to several samples of aquaculture feed and marine species. Precision and accuracy of the analytical method were determined using the reference material from the International Atomic Energy Agency (IAEA-406), showing a good agreement to the referenced values.


Assuntos
Aquicultura , Bromo/química , Cloro/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química
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