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1.
Phys Rev Lett ; 131(16): 162501, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925694

RESUMEN

Neutrinoless double beta decay (0νßß) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νßß) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νßß decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.07±0.02(stat)±0.11(syst)]×10^{18} yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νßß decay rate in ^{100}Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ_{3,1}=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νßß decay.

2.
Chemosphere ; 343: 140296, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37769908

RESUMEN

An extended suspect screening approach for the comprehensive chemical characterization of scrubber discharge waters from exhaust gas cleaning systems (EGCSs), used to reduce atmospheric shipping emissions of sulphur oxides, was developed. The suspect screening was based on gas chromatography coupled with high-resolution mass spectrometry (GC-HRMS) and focused on the identification of polycyclic aromatic hydrocarbons (PAHs) and their alkylated derivatives (alkyl-PAHs), which are among the most frequent and potentially toxic organic contaminants detected in these matrices. Although alkyl-PAHs can be even more abundant than parent compounds, information regarding their occurrence in scrubber waters is scarce. For compound identification, an in-house compound database was built, with 26 suspect groups, including 25 parent PAHs and 23 alkyl-PAH homologues. With this approach, 7 PAHs and 12 clusters of alkyl-PAHs were tentatively identified, whose occurrence was finally confirmed by target analysis using GC coupled with tandem mass spectrometry (GC-MS/MS). Finally, a retrospective analysis was performed to identify other relevant (poly)cyclic aromatic compounds (PACs) of potential concern in scrubber waters. According to it, 18 suspect groups were tentatively identified, including biphenyls, dibenzofurans, dibenzothiophenes and oxygenated PAHs derivatives. All these compounds could be used as relevant markers of scrubber water contamination in heavy traffic marine areas and be considered as potential stressors when evaluating scrubber water toxicity.

3.
Sci Total Environ ; 818: 151697, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-34793799

RESUMEN

The effect of anaerobic treatment of swine manure at 35 °C (mesophilic) and 55 °C (thermophilic) on methane production, microbial community and contaminants of emerging concern was investigated. Pasteurization pretreatment and post treatment was also investigated in combination with anaerobic treatment at 35 °C. Specific methane production (SMP), 26 pharmaceutical compounds (PhACs) and five antibiotic resistance genes (ARGs) (qnrS, tetW, ermB, sul1 and blaTEM) were evaluated. Mesophilic treatment resulted in the highest SMP regardless of whether pasteurization was applied. Marbofloxacin was the most abundant antibiotic in swine manure. In general, all groups of PhACs showed higher removals under thermophilic temperatures as compared to mesophilic. In general, pasteurization pretreatment followed by mesophilic anaerobic digestion provided the highest removals of ARGs. Finally, the genera Streptococcus, Clostridium and Pseudomonas which contain pathogenic species, were present in the swine manure. Streptococcus, which was the most abundant, was decreased during all the treatments, while the others only decreased under certain treatments.


Asunto(s)
Estiércol , Drogas Veterinarias , Anaerobiosis , Animales , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Porcinos , Temperatura
4.
Sci Total Environ ; 789: 147910, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34058579

RESUMEN

This study investigates the effect of psychrophilic, mesophilic and thermophilic temperatures on the anaerobic treatment of slaughterhouse wastewater, in terms of biogas production, occurrence of 30 pharmaceutical compounds of veterinary use, 4 antibiotic resistance genes (ARGs) which provide resistance to tetracyclines (tetW), fluoroquinolones (qnrS), macrolide-lincosamide-streptogramin (ermB) and sulfonamides (sul1) antibiotics, as well as class I integron-integrase gene (intI1), related to horizontal gene transfer. The highest methane yield was obtained at a mesophilic temperature (35 °C) (323 mL CH4/g TCOD) followed by the yield obtained at thermophilic temperature (53 °C) (242 mL CH4/g TCOD). Regarding pharmaceuticals, chlortetracycline, oxytetracycline, tilmicosin, and lincomycin were the most abundant in the slaughterhouse wastewater, being detected predominantly in the solid phase (with median concentrations >200 µg/kg dry weight). On the other hand, ciprofloxacin, ofloxacin, norfloxacin, lincomycin and ibuprofen were the most predominant in the anaerobic digestate regardless of the treatment temperature. Psychrophilic temperatures (21 °C) exhibited moderate to low pharmaceuticals removal, while a large fraction of them were removed at a thermophilic temperature reaching 70-90% removals for tetracycline, macrolides and one sulfonamide (sulfapyridine). The highest relative abundance of the quantified ARGs was found at 53 °C, suggesting that thermophilic temperatures normally associated with better removals of pathogens do not necessarily show better removals of antibiotic resistance genes.


Asunto(s)
Antibacterianos , Preparaciones Farmacéuticas , Mataderos , Anaerobiosis , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Temperatura , Aguas Residuales
5.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34018798

RESUMEN

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

6.
Phys Rev Lett ; 125(14): 141301, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33064531

RESUMEN

We present the first Ge-based constraints on sub-MeV/c^{2} dark matter (DM) particles interacting with electrons using a 33.4 g Ge cryogenic detector with a 0.53 electron-hole pair (rms) resolution, operated underground at the Laboratoire Souterrain de Modane. Competitive constraints are set on the DM-electron scattering cross section, as well as on the kinetic mixing parameter of dark photons down to 1 eV/c^{2}. In particular, the most stringent limits are set for dark photon DM in the 6 to 9 eV/c^{2} range. These results demonstrate the high relevance of Ge cryogenic detectors for the search of DM-induced eV-scale electron signals.

7.
Eur J Neurol ; 27(12): 2604-2615, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32697863

RESUMEN

BACKGROUND AND PURPOSE: The aim was to define the radiological picture of facioscapulohumeral muscular dystrophy 2 (FSHD2) in comparison with FSHD1 and to explore correlations between imaging and clinical/molecular data. METHODS: Upper girdle and/or lower limb muscle magnetic resonance imaging scans of 34 molecularly confirmed FSHD2 patients from nine European neuromuscular centres were analysed. T1-weighted and short-tau inversion recovery (STIR) sequences were used to evaluate the global pattern and to assess the extent of fatty replacement and muscle oedema. RESULTS: The most frequently affected muscles were obliquus and transversus abdominis, semimembranosus, soleus and gluteus minimus in the lower limbs; trapezius, serratus anterior, latissimus dorsi and pectoralis major in the upper girdle. Iliopsoas, popliteus, obturator internus and tibialis posterior in the lower limbs and subscapularis, spinati, sternocleidomastoid and levator scapulae in the upper girdle were the most spared. Asymmetry and STIR hyperintensities were consistent features. The pattern of muscle involvement was similar to that of FSHD1, and the combined involvement of trapezius, abdominal and hamstring muscles, together with complete sparing of iliopsoas and subscapularis, was detected in 91% of patients. Peculiar differences were identified in a rostro-caudal gradient, a predominant involvement of lower limb muscles compared to the upper girdle, and in the higher percentage of STIR hyperintensities in FSHD2. CONCLUSION: This multicentre study defines the pattern of muscle involvement in FSHD2, providing useful information for diagnostics and clinical trial design. Both similarities and differences between FSHD1 and FSHD2 were detected, which is also relevant to better understand the pathogenic mechanisms underlying the FSHD-related disease spectrum.


Asunto(s)
Distrofia Muscular Facioescapulohumeral , Humanos , Extremidad Inferior , Imagen por Resonancia Magnética , Músculo Esquelético/diagnóstico por imagen , Distrofia Muscular Facioescapulohumeral/diagnóstico por imagen , Distrofia Muscular Facioescapulohumeral/genética
8.
Sci Total Environ ; 612: 1387-1406, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28898946

RESUMEN

Antibiotics are an increasing focus of interest due to their high detection frequency in the environment. However, their presence in water bodies is not regulated by environmental policies. This field study investigates, for the first time, the occurrence, behavior and fate of a selection of 53 antibiotics, including up to 10 chemical groups, in an alluvial aquifer originated from manure application in an agricultural region using hydrogeological, hydrochemical and isotopic approaches. Up to 11 antibiotics were found in groundwater corresponding to 4 different chemical groups: fluoroquinolones, macrolides, quinolones and sulfonamides. In surface water, only 5 different antibiotics from 2 chemical groups: fluoroquinolones and sulfonamides, were quantified. The most frequent antibiotics were sulfamethoxazole and ciprofloxacin. Concentrations of antibiotics were in the order of ng/L, with maximum concentrations of 300ng/L in groundwater. Hydrochemistry and isotopic data and geostatistics confirmed the spatial trend observed for nitrates, where nitrate concentrations tend to be higher in the margin areas of the study area, and lower concentrations are found nearby the river. On the other hand, no clear continuous spatial concentration trend of antibiotics was observed in the aquifer, supported by the short spatial correlation found in the variograms. This indicates that the physical-chemical properties and processes of each antibiotic (mainly, sorption and degradation), and other environmental issues, such as a patchy diffuse input and the manure antibiotic content itself, play an important role in their spatial distribution in groundwater. A discussion on the estimation of the antibiotic sorption parameter reveals the difficulties of describing such phenomena. Furthermore, retardation factors will extend over several orders of magnitude, which highly affects the movement of individual antibiotics within the aquifer. To summarize, this study points out the difficulties associated with antibiotic research in groundwater in order to define water resources quality management strategies and environmental regulations.


Asunto(s)
Antibacterianos/análisis , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Nitratos/análisis , Ríos/química , España
9.
Eur Phys J C Part Fields ; 77(11): 785, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31997932

RESUMEN

This paper reports on the development of a technology involving 100 Mo -enriched scintillating bolometers, compatible with the goals of CUPID, a proposed next-generation bolometric experiment to search for neutrinoless double-beta decay. Large mass ( ∼ 1 kg ), high optical quality, radiopure 100 Mo -containing zinc and lithium molybdate crystals have been produced and used to develop high performance single detector modules based on 0.2-0.4 kg scintillating bolometers. In particular, the energy resolution of the lithium molybdate detectors near the Q-value of the double-beta transition of 100 Mo (3034 keV) is 4-6 keV FWHM. The rejection of the α -induced dominant background above 2.6 MeV is better than 8 σ . Less than 10 µ Bq/kg activity of 232 Th ( 228 Th ) and 226 Ra in the crystals is ensured by boule recrystallization. The potential of 100 Mo -enriched scintillating bolometers to perform high sensitivity double-beta decay searches has been demonstrated with only 10 kg × d exposure: the two neutrino double-beta decay half-life of 100 Mo has been measured with the up-to-date highest accuracy as T 1 / 2 = [6.90 ± 0.15(stat.) ± 0.37(syst.)] × 10 18 years . Both crystallization and detector technologies favor lithium molybdate, which has been selected for the ongoing construction of the CUPID-0/Mo demonstrator, containing several kg of 100 Mo .

10.
Eur J Clin Microbiol Infect Dis ; 36(3): 415-420, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27873028

RESUMEN

Recently, plasmid-mediated and, therefore, transferable bacterial polymyxin resistance was discovered in strains from both humans and animals. Such a trait may widely spread geographically, while simultaneously crossing microbial species barriers. This may ultimately render the "last resort" polymyxin antibiotics therapeutically useless. Colistin is currently used to treat infections caused by Gram-negative carbapenemase producers and colistin resistance may lead to practical pan-antibiotic resistance. We here analyzed the medical and diagnostic consequences of (emerging) colistin resistance and propose pathways toward adequate diagnostics for timely detection of both asymptomatic carriage and infection. Culture-based testing using chromogenic and selective media for screening clinical (and veterinary) specimens may constitute key tools for that purpose. Relevant molecular tests are also discussed.


Asunto(s)
Antibacterianos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/microbiología , Animales , Antibacterianos/uso terapéutico , Portador Sano/diagnóstico , Portador Sano/microbiología , Portador Sano/veterinaria , Colistina/uso terapéutico , Transferencia de Gen Horizontal , Bacterias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/veterinaria , Humanos , Plásmidos
11.
Environ Res ; 138: 326-44, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25766939

RESUMEN

The seasonal variations in the occurrence and distribution of pharmaceuticals were evaluated in seawater and sediment of Mar Menor lagoon from spring 2010 to winter 2011. A total of 20 pharmaceuticals in seawater and 14 in sediments were found at concentrations from low ngL(-)(1) up to 168ngL(-)(1) (azithromycin) in seawater and from low ngg(-1) up to 50.3ngg(-1) (xylazine) in sediments. Azithromycin, xylazine and metoprolol were the most ubiquitous compounds in seawater since they were found in all seawater samples collected. Seven compounds were quantified in both matrices: clarithromycin, erythromycin, hydrochlorothiazide, irbesartan, losartan, salicylic acid and valsartan. Seasonal distribution profiles revealed different sources of pollutants associated to both, El Albujón watercourse (which receives the input of a WWTP) and other non-controlled discharges, into the lagoon. In summer the highest concentrations in seawater for most of the pharmaceuticals were detected close to main touristic nuclei, probably as consequence of sources such as the excretion from bathers and/or other non-controlled discharges, these being significantly higher than in autumn and winter for antibiotics. On the contrary, the mean concentration of lorazepam was significantly higher in colder seasons than in warmer ones. Sulfamethoxazole, erythromycin and especially clarithromycin showed hazard quotients higher than 1 in seawater at some areas of this lagoon indicating a potential risk to aquatic organisms in such specific areas.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Preparaciones Farmacéuticas/análisis , Estaciones del Año , Agua de Mar/química , España , Contaminantes Químicos del Agua/análisis
12.
Pediatr Allergy Immunol ; 26(3): 206-217, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25692325

RESUMEN

Cow's milk proteins cause allergic symptoms in 2-3% of all infants. In these individuals, the tolerogenic state of the intestinal immune system is broken, which can lead to sensitization against antigens and eventually to allergic responses. Although a true treatment for food allergy is not available, symptoms can be avoided by providing the infants with hydrolyzed proteins. Hydrolyzed proteins are proteins that are enzymatically degraded. They lack typical allergenic IgE-binding epitopes but are also thought to play a pertinent role in other mechanisms inducing hypoallergenic effects. This review discusses the mechanisms and evidence for immunomodulating properties of cow's milk hydrolysates. Hydrolysates are found to strengthen the epithelial barrier, modulate T-cell differentiation, and decrease inflammation. Some studies suggest a role for hydrolysates in manipulating pathogen recognition receptors signaling as underlying mechanism. Peptides from hydrolysates have been shown to bind to TLR2 and TLR4 and influence cytokine production in epithelial cells and macrophages. Current insight suggests that hydrolysates may actively participate in modulating the immune responses in subjects with cow's milk allergy and those at risk to develop cow's milk allergy. However, more research is required to design effective and reproducible means to develop targeting strategies to modulate the immune response.


Asunto(s)
Mucosa Intestinal/inmunología , Macrófagos/inmunología , Hipersensibilidad a la Leche/dietoterapia , Hidrolisados de Proteína/uso terapéutico , Linfocitos T/inmunología , Animales , Bovinos , Humanos , Tolerancia Inmunológica , Inmunomodulación , Hipersensibilidad a la Leche/inmunología , Receptores de Reconocimiento de Patrones/metabolismo
13.
Sci Total Environ ; 490: 59-72, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24840281

RESUMEN

The seasonal occurrence and distribution of 69 pharmaceuticals along coastal watercourses during 6 sampling campaigns and their input through El Albujón watercourse to the Mar Menor lagoon were determined by UPLC-MS-MS, considering a total of 115 water samples. The major source of pharmaceuticals running into this watercourse was an effluent from the Los Alcazares WWTP, although other sources were also present (runoffs, excess water from irrigation, etc.). In this urban and agriculturally influenced watercourse different pharmaceutical distribution profiles were detected according to their attenuation, which depended on physicochemical water conditions, pollutant input variation, biodegradation and photodegradation rates of pollutants, etc. The less recalcitrant compounds in this study (macrolides, ß-blockers, etc.) showed a relevant seasonal variability as a consequence of dissipation processes (degradation, sorption, etc.). Attenuation was lower, however, for diclofenac, carbamazepine, lorazepam, valsartan, sulfamethoxazole among others, due to their known lower degradability and sorption onto particulate matter, according to previous studies. The maximum concentrations detected were higher than 1000 ng L(-1) for azithromycin, clarithromycin, valsartan, acetaminophen and ibuprofen. These high concentration levels were favored by the limited dilution in this low flow system, and consequently some of them could pose an acute risk to the biota of this watercourse. Considering data from 2009 to 2010, it has been estimated that a total of 11.3 kg of pharmaceuticals access the Mar Menor lagoon annually through the El Albujón watercourse. The highest proportion of this input corresponded to antibiotics (46%), followed by antihypertensives (20%) and diuretics (18%).


Asunto(s)
Monitoreo del Ambiente , Preparaciones Farmacéuticas/análisis , Contaminantes Químicos del Agua/análisis , Mar Mediterráneo , España
14.
Environ Pollut ; 185: 202-12, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24286695

RESUMEN

Occurrence and removal of 81 representative Pharmaceutical Active Compounds (PhACs) were assessed in a municipal WWTP located in a highly industrialized area, with partial water reuse after UV tertiary treatment and discharge to a Mediterranean river. Water monitoring was performed in an integrated way at different points in the WWTP and river along three seasons. Consistent differences between therapeutic classes were observed in terms of influent concentration, removal efficiencies and seasonal variation. Conventional (primary and secondary) treatment was unable to completely remove numerous compounds and UV-based tertiary treatment played a complementary role for some of them. Industrial activity influence was highlighted in terms of PhACs presence and seasonal distribution. Even if global WWTP effluent impact on the studied river appeared to be minor, PhACs resulted widespread pollutants in river waters. Contamination can be particularly critical in summer in water scarcity areas, when water flow decreases considerably.


Asunto(s)
Monitoreo del Ambiente , Preparaciones Farmacéuticas/análisis , Ríos/química , Eliminación de Residuos Líquidos/estadística & datos numéricos , Contaminantes Químicos del Agua/análisis , Industrias , Aguas Residuales/química , Contaminación Química del Agua/estadística & datos numéricos
15.
Water Res ; 47(9): 2959-69, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23561494

RESUMEN

The study evaluates the chronic impact of the antibiotic tetracycline on the biodegradation of organic substrate under anaerobic conditions. The experiments involved an anaerobic sequencing batch reactor fed with a synthetic substrate mixture including glucose, starch and volatile fatty acids, and operated in a sequence of different phases with gradually increasing tetracycline doses of 1.65-8.5 mg/L, for more than five months. Tetracycline exerted a terminal/lethal effect at 8.5 mg/L on the microbial community under anaerobic conditions, which caused the inhibition of substrate/COD utilization and biogas generation and leading to a total collapse of the reactor. The microbial activity could not be recovered and re-started within a period of more than 10 days, even after stopping tetracycline dosing. At lower doses, substrate utilization was not affected but a reduction of 10-20% was observed in the biogas/methane generation, suggesting that substrate utilization of tetracycline to the biomass was limiting their bioavailability. During the experiments, tetracycline was partially removed either through biodegradation or conversion into its by-products. The adverse long-term impact was quite variable for fermenting heterotrophic and methanogenic fractions of the microbial community based on changes inflicted on the composition of remaining/residual organic substrate.


Asunto(s)
Compuestos Orgánicos/aislamiento & purificación , Tetraciclina/farmacología , Anaerobiosis/efectos de los fármacos , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Técnicas de Cultivo Celular por Lotes , Biodegradación Ambiental/efectos de los fármacos , Biocombustibles/análisis , Análisis de la Demanda Biológica de Oxígeno , Reactores Biológicos/microbiología , Dióxido de Carbono/análisis , Ácidos Grasos Volátiles/análisis , Metano/análisis , Tetraciclina/química
16.
J Chromatogr A ; 1288: 63-72, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23522258

RESUMEN

A new sensitive method based on pressurized liquid extraction (PLE) and purification by gel permeation chromatography (GPC) prior to ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed for the determination in fish homogenate, liver and muscle of twenty pharmaceuticals compounds and metabolites from seven commonly used therapeutic families. An extensive matrix effect evaluation was performed in order to select the best approach when analyzing such complex matrices. Limits of detection (MDLs) for the target compounds were in the range of 0.03-0.50ng/g for fish homogenate, 0.01-0.42ng/g for fish muscle, and 0.08-0.98ng/g for fish liver. The method was applied to fish tissues of eleven fish species from four heavily impacted Mediterranean rivers. Nine compounds from five therapeutic families were measured at concentrations higher than MDLs. Highest levels were found in trout liver, with a maximum concentration of 18ng/g for carbamazepine, whereas the most ubiquitous compound was diclofenac.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Residuos de Medicamentos/análisis , Peces , Preparaciones Farmacéuticas/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Residuos de Medicamentos/química , Límite de Detección , Modelos Lineales , Hígado/química , Músculos/química , Preparaciones Farmacéuticas/química , Reproducibilidad de los Resultados
17.
Sci Total Environ ; 440: 236-52, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22809786

RESUMEN

The extensive and intensive use of chemicals in our developed, highly technological society includes more than 100,000 chemical substances. Significant scientific evidence has lead to the recognition that their improper use and release may result in undesirable and harmful side-effects on both the human and ecosystem health. To cope with them, appropriate risk assessment processes and related prioritization schemes have been developed in order to provide the necessary scientific support for regulatory procedures. In the present paper, two of the elements that constitute the core of risk assessment, namely occurrence and hazard effects, have been discussed. Recent advances in analytical chemistry (sample pre-treatment and instrumental equipment, etc.) have allowed for more comprehensive monitoring of environmental pollution reaching limits of detection up to sub ng L(-1). Alternative to analytical measurements, occurrence models can provide risk managers with a very interesting approach for estimating environmental concentrations from real or hypothetical scenarios. The most representative prioritization schemes used for issuing lists of concerning chemicals have also been examined and put in the context of existing environmental policies for protection strategies and regulations. Finally, new challenges in the field of risk-assessment have been outlined, including those posed by new materials (i.e., nanomaterials), transformation products, multi-chemical exposure, or extension of the risk assessment process to the whole ecosystem.


Asunto(s)
Exposición a Riesgos Ambientales , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/toxicidad , Política Ambiental/legislación & jurisprudencia , Regulación Gubernamental , Humanos , Modelos Teóricos , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
18.
Kidney Blood Press Res ; 34(1): 1-11, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21071956

RESUMEN

A high-salt diet is one of the major risk factors in the development and maintenance of hypertension. Numerous experimental and observational studies have confirmed the association of sodium intake with blood pressure levels. The effects of a high-salt diet are related to the function of the renin-angiotensin system, which is normally suppressed by a high-salt diet. Endothelial dysfunction probably plays an important role in the influence of high sodium intake on blood pressure, although the exact mechanisms remain elusive. Genetic factors are known to be very important, and various consomic and congenic rat strains as animal models have proven to be very useful in bringing us a step closer to understanding the interaction between salt intake and hypertension. In this article, experimental data obtained in studies on animals and humans, as well as epidemiological data are reviewed.


Asunto(s)
Hipertensión/epidemiología , Hipertensión/etiología , Sistema Renina-Angiotensina/fisiología , Sodio en la Dieta/administración & dosificación , Animales , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Dieta Hiposódica/efectos adversos , Dieta Hiposódica/métodos , Dieta Hiposódica/tendencias , Humanos , Hipertensión/fisiopatología , Sistema Renina-Angiotensina/efectos de los fármacos , Factores de Riesgo , Sodio en la Dieta/efectos adversos , Sodio en la Dieta/toxicidad
19.
J Microsc ; 235(1): 1-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19566622

RESUMEN

We report here the development of instruments and protocols for carrying out high numerical aperture immersion light microscopy on cryogenic specimens. Imaging by this modality greatly increases the lifetimes of fluorescence probes, including those commonly used for protein localization studies, while retaining the ability to image the specimen with high fidelity and spatial resolution. The novel use of a cryogenic immersion fluid also minimizes the refractive index mismatch between the sample and lens, leading to a more efficient coupling of the light from the sample to the image forming system. This enhancement is applicable to both fluorescence and transmitted light microscopy techniques. The design concepts used for the cryogenic microscope can be applied to virtually any existing light-based microscopy technique. This prospect is particularly exciting in the context of 'super-resolution' techniques, where enhanced fluorescence lifetime probes are especially useful. Thus, using this new modality it is now possible to observe dynamic events in a live cell, and then rapidly vitrify the specimen at a specific time point prior to carrying out high-resolution imaging. The techniques described can be used in conjunction with other imaging modalities in correlated studies. We have also developed instrumentation to perform cryo-light imaging together with soft X-ray tomography on the same cryo-fixed specimen as a means of carrying out high content, quantifiable correlated imaging analyses. These methods are equally applicable to correlated light and electron microscopy of frozen biological objects.


Asunto(s)
Congelación , Microscopía Fluorescente/métodos , Microscopía/métodos , Manejo de Especímenes/métodos , Escherichia coli/citología , Tomografía por Rayos X/métodos
20.
Talanta ; 76(3): 580-90, 2008 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-18585324

RESUMEN

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.


Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Cromatografía de Gases y Espectrometría de Masas/normas , Espectrometría de Masas en Tándem/normas , Contaminantes Químicos del Agua/análisis , Cromatografía Liquida , Europa (Continente) , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Extracción en Fase Sólida
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