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2.
Rev Med Interne ; 38(8): 551-554, 2017 Aug.
Artículo en Francés | MEDLINE | ID: mdl-28129954

RESUMEN

INTRODUCTION: Reactive arthritis due to Clostridium difficile infection is uncommon. CASE REPORTS: We report two cases of reactive arthritis associated with C. difficile infection that occurred in a 40-year-old woman and a 47-year-old man. The literature review between 1976 (date of first reported case) and 2016 retrieved 54 observations (including our two cases). Reactive arthritis occurs most frequently in young subjects after a variable time frame according to C. difficile infection, involving one or several articulations. The issue is generally favourable with or without anti-inflammatory treatment. CONCLUSION: The increasing incidence of C. difficile infection makes more likely the occurrence of this related reactive arthritis. Therefore physicians should consider it in differential diagnosis of bacterial infections capable of causing reactive arthritis.


Asunto(s)
Artritis Reactiva/microbiología , Clostridioides difficile/fisiología , Infecciones por Clostridium/complicaciones , Adulto , Artritis Reactiva/diagnóstico , Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad
3.
Aquat Toxicol ; 78 Suppl 1: S124-6, 2006 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-16638619

RESUMEN

Within the three-year European Research Project BEEP (Biological Effects of Environmental Pollution in marine ecosystems), a workshop was carried out at the facility of Akvamiljø a.s. with the scientific support of IRIS (International Research Institute of Stavanger) researchers. Validation of newly developed biomarkers, especially at the molecular level, was the core part of the activity. Two large scale mesocosm exposures were done and samples shared between the participants (about 30 Institute), allowing an integrated approach for studying the effects of several pollutants selected as environmentally important issues (i.e. PAHs, alkyl phenols, bisphenol A, diallyl phthalate and polybrominated diphenyl ether). In addition, a field study (Visne, Norway) has been performed for the validations of biomarkers under environmental conditions. The Stavanger workshop demonstrates the importance of collaboration between researchers to establish common ways to proceed in biomarker analysis. The common exposures encourage a joint strategy for planning biomonitoring activity. A clarification in this direction is needed to coordinate results from numerous studies about the environmental impact of pollutants which are currently carried out all over Europe and around the world. Expertise in various disciplines is required to plan and perform a successful monitoring activity and to study/predict the effect of environmental pollutants. Biologists, chemists, statisticians and environmental researchers should always be included. The Stavanger workshop also indicated the importance of developing multivariate statistical methods to enable interpretation of complex data sets. It is of interest to develop statistical tools which can integrate the results from a battery of biomarkers in order to obtain a more complete picture of environmental impact.


Asunto(s)
Biomarcadores , Exposición a Riesgos Ambientales , Toxicología/métodos , Toxicología/normas , Contaminación Química del Agua , Animales , Conducta Cooperativa , Educación , Biología Marina/normas , Investigación/normas
4.
Water Res ; 38(7): 1817-21, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15026236

RESUMEN

The green alga, Scenedesmus subspicatus was exposed for 7 days to a series of PAHs (polyaromatic hydrocarbons) of increased molecular weight from two to five rings [naphthalene (Nap), anthracene (Ant), phenanthrene (Phe), pyrene (Pyr) and benzo(a)pyrene (BaP)]. The toxicity measured as population growth inhibition by individual PAH to the S. subspicatus followed the order: BaP>Pyr>Ant>Phe>Nap. These results confirmed that the toxicity potential of PAHs seems to be strongly influenced by their physico-chemical properties (aqueous solubility, K(ow), coefficient of volatilization, etc.) and the conditions of algae culture (light, presence of nitrate ions, etc.). Consequently, Nap, Phe and Ant having low k(ow) values and low coefficient of volatilization values were less toxic than BaP with the highest k(ow) value, indicating for example why Nap with the lowest EC(50) value was nearly 2 x 10(5) times lower than that of BaP. Moreover, nitrate ions seemed to act directly on the degree of hydroxylated radical reactivity of PAHs, since BaP always remained the most toxic of the compounds tested. The results were also agreed with the QSAR model for toxicity prediction of PAHs to many aquatic organisms.


Asunto(s)
Petróleo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Scenedesmus , Contaminantes Químicos del Agua/toxicidad , Sedimentos Geológicos/química , Hidrocarburos Policíclicos Aromáticos/química , Relación Estructura-Actividad Cuantitativa , Volatilización
5.
Sci Total Environ ; 139-140: 225-36, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8272831

RESUMEN

The GICBEM (Groupe Interface Chimie Biologie des Ecosystèmes Marins) program consists of an evaluation of the ecosystem health status in the Mediterranean Sea mainly based on chemical and biochemical approaches. Specific chemical contaminants (polycyclic aromatic hydrocarbons (PAH), polychlorobiphenyls (PCB), heavy metals) in waters, sediments, and related biotransformation indicators in target organisms (mussels, fish) have been selected for a complete survey of the coastal waters. In order to provide an appropriate sampling program for standardization for each sampling cruise, various aspects have been studied: (a) parameters for the choice of the sample sites; (b) ways of collection the samples (waters, sediments, marine organisms); and (c) preparation of the samples for a short term storage on board ship and for further analyses in the ground laboratory. Methods of preparation and storage of the samples are described and could be used to initiate an environmental banking program including both possible retrospective analyses of chemical pollutants and biochemical indicators. Moreover, the correlation between chemicals (PAH) and biochemical (mixed function oxygenase activities) parameters has been studied and this demonstrates the capability of the enzyme activities as reliable pollution biomarkers.


Asunto(s)
Monitoreo del Ambiente , Metales/análisis , Bifenilos Policlorados/análisis , Compuestos Policíclicos/análisis , Bancos de Tejidos/organización & administración , Contaminantes Químicos del Agua/análisis , Animales , Bivalvos , Ecología , Peces , Mar Mediterráneo , Agua de Mar , Manejo de Especímenes
9.
Biomarkers ; 10(1): 58-71, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16097393

RESUMEN

A battery of biochemical parameters was used to evaluate the response of mussels to a contaminated coastal environment. A multimarker approach was developed, establishing a scale for the classification of the water quality in European coastal sites (BIOMAR European programme). This study allows the evaluation of the temporal trends of this scale when applied to selected sites of European Mediterranean coast (BEEP Biological Effects of Environmental Pollution in Marine Coastal Ecosystems: European programme). Acetylcholinesterase activity (AChE) is highly sensitive to organophosphorus and carbamate insecticides and, to some extent, also to heavy metals. Catalase activity (CAT) and lipid oxidation (evaluated as malonedialdehyde) are markers of oxidative stress, glutathione S-transferase (GST) activity is related to conjugation of organic compounds and benzo(a)pyrene hydroxylase activity (BPH) is a marker of effect of certain planar organic compounds (e.g. polycyclic aromatic hydrocarbons, PAHs). These parameters were measured either in gills (AChE, GST) or digestive gland (BPH, GST, CAT, MDA). For each biomarker, a discriminatory factor was calculated (maximum variation range/confidence interval) and a response index was allocated. For each site, a Multimarker Pollution Index (MPI) was calculated as the sum of the response index of each of the five more discriminating biomarkers. As the result of our calculation method, the quality of the coastal environment at each site can be classified according to a five levels scale. Samples collected for five cruises in May 2001, 2002, 2003, and September 2001 and 2002 showed MPI evolutions. The results show that water quality can be classified from class 1 (clean areas in some sites of France, Italy and Spain) to class 4 (high pollution in main harbours). Results of the use of the biomarker scale in WP3 (Work Package Concernant Biomonitoring Programmes in Mediterranean Sea) during the BEEP programme make a strong contribution to the establishment of standardized strategies and methods for internationally agreed protocols for biomarker-based monitoring programmes. In comparison with scale pollution methodology used in the BIOMAR programme, the main contribution of BEEP was (1) to select from discriminatory analysis the biomarkers to be included in calculation of scale pollution; (2) to improve the use of the biomarker index in order to identify the main contaminants by analysis of individual contributions to the MPI; and (3) to apply methodology for temporal trends at sampled sites.


Asunto(s)
Biomarcadores/análisis , Bivalvos/química , Monitoreo del Ambiente , Contaminantes Ambientales/clasificación , Contaminantes Ambientales/toxicidad , Contaminación Ambiental/efectos adversos , Contaminación Ambiental/análisis , Algoritmos , Animales , Análisis Discriminante , Branquias/enzimología , Región Mediterránea
10.
J Chromatogr ; 590(2): 297-303, 1992 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-1560098

RESUMEN

The gas chromatographic retention behaviour, on a smectic liquid crystalline polysiloxane stationary phase, of methyldibenzothiophenes and eighteen C2-dibenzothiophenes (sixteen dimethyldibenzothiophenes and two ethyldibenzothiophenes), out of twenty possible compounds, was investigated. The retention, in addition to vapour pressure and polarity, was greatly influenced by the molecular geometry of the solutes. The major factor affecting this behaviour was the length to breadth ratio (L/B). The elution order of the dimethyldibenzothiophenes was fairly well correlated with L/B values: Roughly, the lower the L/B values, the earlier the dimethyldibenzothiophenes were eluted. However, the solute molecular shape, although of less importance, was also a significant retention-affecting factor, having the contrary effect to L/B values on the elution order. Arc-like molecules (dibenzothiophenes) with groups attached to the outer curved side (i.e., in positions 3 and 4) were retained longer than predicted by L/B values. In contrast, isomers conforming to the arc-like arrangement (i.e., with substituents in positions 1 and 2) were less retained than predicted. The application of these identifications to a crude oil sample is described.


Asunto(s)
Tiofenos/análisis , Cromatografía de Gases , Cristalización
11.
Environ Sci Technol ; 35(15): 3139-43, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11505989

RESUMEN

To clarify the photolytic behavior of polycyclic aromatic hydrocarbons (PAHs) in diesel particulate matter (DPM) deposited on the ground, we determined the rate constants and half-lives for the photodegradation of benzo[a]pyrene (BaPy), phenanthrene (Phe), fluoranthene (Flrt), pyrene (Py), and chrysene (Ch) in air for three probable cases: (1) DPM is placed on an inert surface, (2) DPM is mixed with soil, and (3) PAHs are leached from DPM and adsorbed to soil. We found that BaPy and Phe degraded relatively quickly in case 1. However, in case 2, these PAHs degraded more slowly due to the effect of the presence of soil. Flrt, Py, and Ch were stable. In case 3, photodegradation of adsorbed PAHs in soil was strongly inhibited as a function of soil depth. Although these findings were obtained at extreme light intensities, they may occur under real world conditions. Conversion factors for obtaining rate constants and half-lives for PAHs on the ground under sunlight are presented. We conclude that under the average intensity of sunlight in Tokyo, photodegradation of PAHs in DPM deposited on an inert surface is very slow.


Asunto(s)
Contaminantes Atmosféricos/análisis , Hidrocarburos Policíclicos Aromáticos/química , Emisiones de Vehículos/análisis , Monitoreo del Ambiente , Semivida , Tamaño de la Partícula , Fotólisis , Suelo , Luz Solar
12.
Fresenius J Anal Chem ; 367(2): 165-71, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-11225877

RESUMEN

A microwave-assisted protocol has been developed using focussed microwaves at atmospheric pressure for the extraction of PAHs and PCBs from sediments. It combines extraction and purification assisted by microwaves. This protocol has been applied to the quantification of 12 individual PAHs, 8 individual PCBs and 8 PCB coeluted mixtures from two Standard Reference Materials and one natural sediment. The results for both classes of compounds (PAHs and PCBs) are good in terms of recoveries, which are always greater than 70% and in most cases around 100%. The reproducibility is also good with coefficients of variation below 10% in most cases. This protocol has the great advantage of saving time, the time dedicated to the preparation / extraction assisted by microwaves being reduced to less than half an hour.


Asunto(s)
Sedimentos Geológicos/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Presión Atmosférica , Cromatografía de Gases/métodos , Microondas , Bifenilos Policlorados/aislamiento & purificación , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Agua de Mar
13.
C R Acad Sci III ; 324(12): 1149-55, 2001 Dec.
Artículo en Francés | MEDLINE | ID: mdl-11803816

RESUMEN

Embryos and larvae of bivalves are frequently used in marine ecotoxicology for the purpose of assessing seawater quality, because they are very sensitive to pollutants and provide rapid responses. Laboratory studies, however, cannot accurately simulate natural conditions. We conducted bivalve embryo-larval studies in situ at the marina of Arcachon (south-west French Atlantic coast), in order to assess 'biological quality' of the water. One experiment conducted in winter 1999 (temperatures of 10 degrees C) with embryos of the Mediterranean mussel, Mytilus galloprovincialis, has shown that such tests are practicable in winter at low temperatures. This study did not show any deterioration in 'biological quality' of the water. Four series of experiments were subsequently performed during summer 2000 (ambient water temperatures of 19 to 22.4 degrees C) with embryos of the Japanese oyster, Crassostrea gigas. The results show that the 'sea water biological quality' deteriorates from the port entrance towards its inner part. To our knowledge, this is the first investigation of the marine environment in which bivalve embryos have been used in situ. They are very suitable for this type of study, because bivalve embryos and larvae are more sensitive to pollutants than the adults, and also because they belong to euryhaline species and the embryos tolerate summer temperatures (both species) as well as winter temperatures (mussels), allowing biomonitoring to be conducted all over the year.


Asunto(s)
Bivalvos/fisiología , Ostreidae/fisiología , Agua de Mar , Animales , Bioensayo/métodos , Bivalvos/embriología , Embrión no Mamífero/fisiología , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Larva/fisiología , Ostreidae/embriología
14.
Anal Bioanal Chem ; 372(1): 196-204, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11939194

RESUMEN

A multi-residue analysis procedure using microwave-assisted extraction and pre-purification has been developed for the combined analysis of polycyclic aromatic hydrocarbons (PAH), polychlorobiphenyls (PCB), and organochlorine pesticides (OCP) in marine sediments. This procedure has been validated with certified marine sediment. Several surrogate standards have been employed and the use of octachloronaphthalene (OCN) as a surrogate standard for organochlorine determination in this matrix is discussed. The recoveries of all compounds were high (>70%) and the relative standard deviations are of the same order as the certified values. Different analytical problems are discussed, including DDT degradation in gas chromatography and laboratory PCB background levels. Quantification problems encountered for two pesticides (cis-chlordane and trans-nonachlor) were attributed to PAH interference in the GC-ECD chromatogram.


Asunto(s)
Cromatografía/métodos , Sedimentos Geológicos/química , Insecticidas/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Clordano/análisis , Cromatografía de Gases/métodos , Cromatografía Liquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Clorados/análisis , Espectrometría de Masas , Estándares de Referencia , Estereoisomerismo
15.
Ecotoxicol Environ Saf ; 42(1): 1-8, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9931231

RESUMEN

The accumulation kinetics in the freshwater mollusk Corbicula fluminea were measured for sediment-associated selected polycyclic aromatic hydrocarbons (PAHs), namely, anthracene (Ant), phenanthrene (Phe), pyrene (Pyr), and benzo [a] pyrene (BaP). The desorption from sediment to water was not only related to water solubility, but also depended on structural and physicochemical properties of PAHs (molecular weight, molecular area, octanol/water partition coefficient Kow). Uptake of PAHs by mollusks was very fast in the first 24 h and maximum for low-molecular-weight compounds. Then animal concentrations decreased significantly after the first day for Ant and Phe, after the second day for Pyr, and after the second week for BaP (at this time the BaP concentration was higher than concentrations of the other PAHs). The kinetic data suggest that PAH uptake is related to desorption from sediment particles. Log PAH uptake is inversely related to log Kow. Bioavailability of sediment-sorbed PAHs declined with contact time between sediment and animals. Assimilation from ingested material may be significant for the more strongly sorbed compound (BaP). PAHs with low Kow values become biologically unavailable more rapidly and more efficiently excreted.


Asunto(s)
Moluscos/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes Químicos del Agua/metabolismo , Absorción , Animales , Antracenos/metabolismo , Benzo(a)pireno/metabolismo , Sedimentos Geológicos , Modelos Lineales , Fenantrenos/metabolismo , Pirenos/metabolismo
16.
Artículo en Inglés | MEDLINE | ID: mdl-1677868

RESUMEN

1. MFO enzyme activities were measured in microsomes from whole mussels (Mytilus galloprovincialis) comber livers (Serranus cabrilla), or Posidonia oceanica etiolated tissues, and PAH contents were determined in sediments collected in coastal locations of the French Riviera and Corsica during 3 oceanographic cruises in 1987-1988. 2. BaP activities in mussel and EROD activities measured in fish were strongly correlated to the log of PAH content in sediments. The first results for CA4H in Posidonia showed significant differences related to PAH pollution levels. The increase in MFO activities measured in Corsica in summer 1988 indicated a recent petroleum contamination.


Asunto(s)
Monitoreo del Ambiente/métodos , Microsomas/enzimología , Oxigenasas de Función Mixta/metabolismo , Compuestos Policíclicos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Bivalvos/enzimología , Peces/metabolismo , Francia , Mar Mediterráneo , Plantas/enzimología , Contaminantes del Suelo/análisis
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