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1.
Sci Total Environ ; 896: 165264, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37400037

RESUMO

Coastal lagoons are among the most productive and biodiverse systems in the world and are important sentinels of climate change. The Mar Menor is one of the largest coastal lagoons in the Mediterranean, providing a variety of ecosystem services and resources to the community. However, in recent decades this lagoon has suffered drastic changes and degradation caused by human activities. We analyzed the concentration of dissolved organic carbon (DOC) and the optical properties of dissolved organic matter (DOM) in the water column and sediment pore water during the summer and winter of 2018 and during eighteen months from 2016 to 2018. Overall, we found that the composition of DOM is mainly related to and enhanced by anthropogenic activities and microbial metabolism. DOM enters the lagoon via urban and agricultural runoff, drainage systems, and wastewater treatment plants. Additionally, strong microbial metabolism in sediments leads to differences in DOM composition between water and sediments. In the water column, humic-like components accounted for 71 % of the total DOM, while protein-like compounds were most abundant in sediment pore water. We observed a strong seasonal variability associated with precipitation and the system collapse in 2016 (phytoplankton bloom), which resulted in the death of 80 % of macrophytes. The sediments act as a source of DOM to the overlying water, likely due to relatively high organic matter content and intense microbial activity, primarily through anaerobic pathways. Benthic fluxes of DOC ranged from 5.24 to 33.30 mmol m-2 d-1, being higher in winter than summer 2018 and decreasing from north to south, likely related to lower residence time in the northern basin, groundwater discharge and accumulation of organic matter from the dead meadows. We estimate a net flux of DOC from the Mar Menor toward the Mediterranean Sea of 1.57 × 107 mol yr-1.

2.
Sci Total Environ ; 775: 145020, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-33621880

RESUMO

Forecasting of climate change impacts on marine aquaculture production has become a major research task, which requires taking into account the biases and uncertainties arising from ocean climate models in coastal areas, as well as considering culture management strategies. Focusing on the suspended mussel culture in the NW Iberian coastal upwelling system, we simulated current and future mussel growth by means of a multistructural net production Dynamic Energy Budget (DEB) model. We considered two scenarios and three ocean climate models to account for climate uncertainty, and applied a bias correction to the climate models in coastal areas. Our results show that the predicted impact of climate change on mussel growth is low compared with the role of the seeding time. However, the response of mussels varied across climate models, ranging from a minor growth decline to a moderate growth increase. Therefore, this work confirms that an accurate forecasting of climate change impacts on shellfish aquaculture should take into account the variability linked to both management strategies and climate uncertainty.


Assuntos
Bivalves , Mytilus , Animais , Aquicultura , Mudança Climática , Alimentos Marinhos
3.
Front Microbiol ; 11: 918, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582044

RESUMO

Prokaryotes play a fundamental role in decomposing organic matter in the ocean, but little is known about how microbial metabolic capabilities vary at the global ocean scale and what are the drivers causing this variation. We aimed at obtaining the first global exploration of the functional capabilities of prokaryotes in the ocean, with emphasis on the under-sampled meso- and bathypelagic layers. We explored the potential utilization of 95 carbon sources with Biolog GN2 plates® in 441 prokaryotic communities sampled from surface to bathypelagic waters (down to 4,000 m) at 111 stations distributed across the tropical and subtropical Atlantic, Indian, and Pacific oceans. The resulting metabolic profiles were compared with biological and physico-chemical properties such as fluorescent dissolved organic matter (DOM) or temperature. The relative use of the individual substrates was remarkably consistent across oceanic regions and layers, and only the Equatorial Pacific Ocean showed a different metabolic structure. When grouping substrates by categories, we observed some vertical variations, such as an increased relative utilization of polymers in bathypelagic layers or a higher relative use of P-compounds or amino acids in the surface ocean. The increased relative use of polymers with depth, together with the increases in humic DOM, suggest that deep ocean communities have the capability to process complex DOM. Overall, the main identified driver of the metabolic structure of ocean prokaryotic communities was temperature. Our results represent the first global depiction of the potential use of a variety of carbon sources by prokaryotic communities across the tropical and the subtropical ocean and show that acetic acid clearly emerges as one of the most widely potentially used carbon sources in the ocean.

4.
J Antimicrob Chemother ; 73(8): 2171-2176, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29788066

RESUMO

Objectives: To analyse lipid changes and tolerability in a cohort of HIV-infected patients who switched their antiretroviral regimens to rilpivirine/emtricitabine/tenofovir (RPV/FTC/TDF) in a real-world setting. Methods: PRO-STR is a 48 week prospective observational post-authorization study in 25 hospitals. Patients with a viral load <1000 copies/mL, receiving at least 12 months of combination ART (cART), with constant posology for at least the prior 3 months, were categorized according to previous treatment [NNRTI or ritonavir-boosted PI (PI/r)]. Analytical tests were performed at the baseline visit, between week 16 and week 32, and at week 48. Results: A total of 303 patients were included (mean age 46.6 years; male 74.0%; previous treatment 74.7% NNRTI and 25.3% PI/r). Both groups exhibited significantly reduced lipid profiles, except for HDL cholesterol, for which a non-significant increase was observed. [NNRTI patients: total cholesterol (baseline: 195.5 ±âŸ38.4 mg/dL; week 48: 171.0 ±âŸ35.5 mg/dL), total cholesterol/HDL ratio (baseline: 4.2 ±âŸ1.2; week 48: 4.0 ±âŸ1.2), HDL (baseline: 49.1 ±âŸ12.0 mg/dL; week 48: 49.2 ±âŸ45.8 mg/dL), LDL (baseline: 119.2 ±âŸ30.2 mg/dL; week 48: 114.2 ±âŸ110.7 mg/dL), and triglycerides (baseline: 136.6 ±âŸ86.8 mg/dL; week 48: 113.4 ±âŸ67.8 mg/dL); PI/r patients: total cholesterol (baseline: 203.2 ±âŸ48.8 mg/dL; week 48: 173.4 ±âŸ36.9 mg/dL), total cholesterol/HDL ratio (baseline: 4.7 ±âŸ1.6; week 48: 4.0 ±âŸ1.2), HDL (baseline: 46.4 ±âŸ12.5 mg/dL; week 48: 52.1 ±âŸ54.4 mg/dL), LDL (baseline: 127.0 ±âŸ36.3 mg/dL; week 48: 111.4 ±âŸ35.8 mg/dL), and triglycerides (baseline: 167.6 ±âŸ107.7 mg/dL; week 48: 122.7 ±âŸ72.1 mg/dL)]. The most common intolerances were neuropsychiatric in the NNRTI patients and gastrointestinal and metabolic in the PI/r patients, and these intolerances were significantly reduced in both groups at week 48 [NNRTI: neuropsychiatric (baseline: 81.3%; week 48: 0.0%); PI/r: gastrointestinal (baseline: 48.7%; week 48: 0.0%) and metabolic (baseline: 42.1%; week 48: 0.0%)]. Conclusions: RPV/FTC/TDF improved the lipid profiles and reduced the intolerances after switching from NNRTI or PI-based regimens, in a cohort of HIV-infected patients.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Substituição de Medicamentos , Dislipidemias/patologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Lipídeos/sangue , Adulto , Emtricitabina/administração & dosagem , Feminino , Humanos , Masculino , Estudos Prospectivos , Rilpivirina/administração & dosagem , Tenofovir/administração & dosagem , Carga Viral
5.
Sci Rep ; 6: 29405, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27384527

RESUMO

Identifying the environmental factors driving larval settlement processes is crucial to understand the population dynamics of marine invertebrates. This work aims to go a step ahead and predict larval presence and intensity. For this purpose we consider the influence of solar irradiance, wind regime and continental runoff on the settlement processes. For the first time, we conducted a 5-years weekly monitoring of Mytilus galloprovincialis settlement on artificial suspended substrates, which allowed us to search for interannual variability in the settlement patterns. Comparison between the seasonal pattern of larval settlement and solar irradiance, as well as the well-known effect of solar irradiance on water temperature and food availability, suggest that solar irradiance indirectly influences the settlement process, and support the use of this meteorological variable to predict settlement occurrence. Our results show that solar irradiance allows predicting the beginning and end of the settlement cycle a month in advance: Particularly we have observed that solar irradiance during late winter indirectly drives the timing and intensity of the settlement onset, Finally, a functional generalise additive model, which considers the influence of solar irradiance and continental runoff on the settlement process, provides an accurate prediction of settlement intensity a fortnight in advance.


Assuntos
Bivalves , Biologia Marinha , Energia Solar , Animais , Bivalves/crescimento & desenvolvimento , Monitoramento Ambiental , Comportamento Alimentar , Larva , Modelos Teóricos , Dinâmica Populacional , Probabilidade , Estações do Ano , Temperatura
7.
ISME J ; 10(3): 596-608, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26251871

RESUMO

The deep-sea is the largest biome of the biosphere, and contains more than half of the whole ocean's microbes. Uncovering their general patterns of diversity and community structure at a global scale remains a great challenge, as only fragmentary information of deep-sea microbial diversity exists based on regional-scale studies. Here we report the first globally comprehensive survey of the prokaryotic communities inhabiting the bathypelagic ocean using high-throughput sequencing of the 16S rRNA gene. This work identifies the dominant prokaryotes in the pelagic deep ocean and reveals that 50% of the operational taxonomic units (OTUs) belong to previously unknown prokaryotic taxa, most of which are rare and appear in just a few samples. We show that whereas the local richness of communities is comparable to that observed in previous regional studies, the global pool of prokaryotic taxa detected is modest (~3600 OTUs), as a high proportion of OTUs are shared among samples. The water masses appear to act as clear drivers of the geographical distribution of both particle-attached and free-living prokaryotes. In addition, we show that the deep-oceanic basins in which the bathypelagic realm is divided contain different particle-attached (but not free-living) microbial communities. The combination of the aging of the water masses and a lack of complete dispersal are identified as the main drivers for this biogeographical pattern. All together, we identify the potential of the deep ocean as a reservoir of still unknown biological diversity with a higher degree of spatial complexity than hitherto considered.


Assuntos
Bactérias/isolamento & purificação , Biodiversidade , Água do Mar/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Oceanos e Mares , Filogenia , Cloreto de Sódio/análise , Cloreto de Sódio/metabolismo
8.
Nat Commun ; 6: 5986, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-25631682

RESUMO

Marine dissolved organic matter (DOM) is one of the largest reservoirs of reduced carbon on Earth. In the dark ocean (>200 m), most of this carbon is refractory DOM. This refractory DOM, largely produced during microbial mineralization of organic matter, includes humic-like substances generated in situ and detectable by fluorescence spectroscopy. Here we show two ubiquitous humic-like fluorophores with turnover times of 435±41 and 610±55 years, which persist significantly longer than the ~350 years that the dark global ocean takes to renew. In parallel, decay of a tyrosine-like fluorophore with a turnover time of 379±103 years is also detected. We propose the use of DOM fluorescence to study the cycling of resistant DOM that is preserved at centennial timescales and could represent a mechanism of carbon sequestration (humic-like fraction) and the decaying DOM injected into the dark global ocean, where it decreases at centennial timescales (tyrosine-like fraction).


Assuntos
Escuridão , Internacionalidade , Oceanos e Mares , Compostos Orgânicos/análise , Fluorescência , Oxigênio/análise , Navios , Solubilidade , Fatores de Tempo , Água
9.
Environ Microbiol ; 10(4): 906-17, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18215158

RESUMO

We used mesocosm experiments to study the bacterioplankton community in a highly dynamic coastal ecosystem during four contrasting periods of the seasonal cycle: winter mixing, spring phytoplankton bloom, summer stratification and autumn upwelling. A correlation approach was used in order to measure the degree of coupling between the dynamics of major bacterial groups, heterotrophic carbon cycling and environmental factors. We used catalysed reporter deposition-fluorescence in situ hybridization to follow changes in the relative abundance of the most abundant groups of bacteria (Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes). Bacterial carbon flux-related variables included bacterial standing stock, bacterial production and microbial respiration. The environmental factors included both, biotic variables such as chlorophyll-a concentration, primary production, phytoplankton extracellular release, and abiotic variables such as the concentration of dissolved inorganic and organic nutrients. Rapid shifts in the dominant bacterial groups occurred associated to environmental changes and bacterial bulk functions. An alternation between Alphaproteobacteria and Bacteroidetes was observed associated to different phytoplankton growth phases. The dominance of the group Bacteroidetes was related to high bacterial biomass and production. We found a significant, non-spurious, linkage between the relative abundances of major bacterial groups and bacterial carbon cycling. Our results suggest that bacteria belonging to these major groups could actually share a function in planktonic ecosystems.


Assuntos
Bactérias/metabolismo , Carbono/metabolismo , Ecossistema , Plâncton/metabolismo , Água do Mar/microbiologia , Microbiologia da Água , Estações do Ano , Água do Mar/análise
10.
Mar Environ Res ; 62(5): 388-413, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16899290

RESUMO

Plankton samples (20-350 microm and >350 microm) collected at three transects along the Galician coast (NW Spain) were analysed for individual aliphatic and aromatic hydrocarbons by GC-MS. Sample collection was performed in April-July 2003, after the Prestige oil spill (November 2002), to determine whether the hydrocarbons released into the water column as a consequence of the spill were accumulated by the planktonic communities during the subsequent spring and early summer blooms. Surface sediments were also collected to assess the presence of the spilled oil, removed from the water column by downward particle transport. Plankton concentrations of PAHs (Sigma14 parent components) were in the range of 25-898 ng g(-1)dw, the highest values being close to coastal urban areas. However, the individual distributions were highly dominated by alkyl naphthalenes and phenanthrenes, paralleling those in the water dissolved fraction. The detailed study of petrogenic molecular markers (e.g. steranes and triterpanes, and methyl phenanthrenes and dibenzothiophenes) showed the occurrence of background petrogenic pollution but not related with the Prestige oil, with the possible exception of the station off Costa da Morte in May 2003, heavily oiled after the accident. The dominant northerly wind conditions during the spring and early summer 2003, which prevented the arrival of fresh oil spilled from the wreck, together with the heavy nature of the fuel oil, which was barely dispersed in seawater, and the large variability of planktonic cycles, could be the factors hiding the acute accumulation of the spilled hydrocarbons. Then, with the above exception, the concentrations of PAHs found in the collected samples, mostly deriving from chronic pollution, can be considered as the reference values for the region.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos Acíclicos/análise , Hidrocarbonetos Aromáticos/análise , Plâncton/química , Poluentes Químicos da Água/análise , Animais , Biodiversidade , Clorofila/análise , Monitoramento Ambiental , Hidrocarbonetos Acíclicos/química , Hidrocarbonetos Aromáticos/química , Tamanho da Partícula , Petróleo , Plâncton/classificação , Estações do Ano , Cloreto de Sódio/análise , Espanha , Temperatura , Poluentes Químicos da Água/química , Vento
11.
Mar Pollut Bull ; 53(5-7): 239-49, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16256146

RESUMO

Hydrographic data collected during the cruise HIDROPRESTIGE were combined with meteorological and dynamic data provided by remote sensors and drifting/moored buoys, to describe the surface circulation of the Northern Iberian basin in March-April 2003. Sea surface winds transported the floating Prestige oil slicks from the sinking area to the continental slope off the Rías Baixas in 1/2 month: the surface current intensity was 2% of the wind intensity and it was rotated clockwise 5 degrees from the wind direction. Mesoscale cyclonic and anticyclonic structures west of 10 degrees W increased the residence time of oil patches in the Northern Iberian basin, as compared with the expected southwards flow of the Iberian current (IC). On the other hand, the Iberian poleward current (IPC) formed a marked surface front with coastal waters, preventing the entry of fuel oil into the rías. PAHs in the surface layer during the cruise were <0.5 microgL(-1), except in the Galicia bank (approximately 1 microg L(-1); where the Prestige tanker was still leaking) and the vicinity of Cape Fisterra (approximately 1.5 microg L(-1); where the convergence front between the IPC and coastal waters vanished).


Assuntos
Desastres , Óleos Combustíveis , Poluição Química da Água , Oceano Atlântico , Humanos , Oceanografia , Estações do Ano , Água do Mar , Navios , Espanha , Temperatura , Movimentos da Água
12.
Rev Clin Esp ; 202(8): 430-4, 2002 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-12199992

RESUMO

INTRODUCTION AND OBJECTIVES: Deep vein thrombosis (DVT) is a common disease, with a high risk of complications persisting for years. Until recently, the treatment of this condition was on an hospitalary basis. Nevertheless, there is growing evidence suggesting an adequate management on an ambulatory basis with low molecular weight heparin (LMWH). Based upon these observations, and observational study was performed to determine short-term ad long-term complications of DVT treated by a Home Care Unit (HCU). METHODS: A total of 125 patients diagnosed of DVT by means of Doppler echography were treated on an ambulatory basis with subcutaneous nadroparine followed by oral anticoagulants (OAC) or LMWH alone, when a contraindication for acenocumarol use was present. The characteristics of the study population and their risk factors were studied, as well as the presence of bleeding or relapse during the acute period. Once the acute period with surveillance and treatment by the DHU was over, patients were followed at the Outpatient Clinics of the Internal Medicine Department. At each visit, the long-term complications were assessed: relapse, postflebitis syndrome (PFS), or death. RESULTS: The most common short-term complications were bleeding (3.2%) and relapse (7.3%). Eighteen percent of patients showed liver toxicity (increase of at least a 1.5 fold in the basal values of transaminases) secondary to the use of nadroparine. Nevertheless, this toxicity was mild in all cases and subsided when the medication was stopped. With a mean follow-up of 15.4 months, an overall 16.5% of patients relapsed, 25.8 % of patients had a PFS, and 23.7% of patients died. Death was associated with the presence of some risk factors (32.7% versus 7.69%; p = 0.004), and particularly when this risk factor was a tumor (75% versus 12%; p < 0.001). CONCLUSIONS: Deep vein thrombosis is a condition associated with common complications, both in the acute period and in the long-term. Nevertheless, it can be treated safely and efficiently by a HCU. This disease is associated with a high risk of mortality, particularly because it is usually associated with severe diseases.


Assuntos
Assistência Ambulatorial , Anticoagulantes/uso terapêutico , Trombose Venosa/tratamento farmacológico , Idoso , Anticoagulantes/efeitos adversos , Feminino , Heparina de Baixo Peso Molecular/efeitos adversos , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Nadroparina/efeitos adversos , Nadroparina/uso terapêutico , Análise de Sobrevida , Trombose Venosa/complicações
13.
Rev. clín. esp. (Ed. impr.) ; 202(8): 430-434, ago. 2002.
Artigo em Es | IBECS | ID: ibc-19510

RESUMO

Introducción y objetivos. La trombosis venosa profunda (TVP) es una enfermedad frecuente, con un alto riesgo de complicaciones que persisten durante años. Hasta hace poco tiempo su tratamiento era intrahospitalario, sin embargo cada vez existe más evidencia sobre su manejo adecuado de forma ambulatoria con heparina de bajo peso molecular (HBPM). En base a esto se presenta un estudio observacional para determinar las complicaciones a corto y largo plazo de la TVP tratada por una Unidad de Hospitalización a Domicilio (HAD).Métodos. Ciento veinticinco pacientes diagnosticados por ecografia doppler de TVP fueron tratados de forma ambulatoria con nadroparina subcutánea seguida de anticoagulantes orales (ACO) o HPBM sólo, en caso de que existiese contraindicación para el acenocumarol. Se evaluaron las características de la población y sus factores de riesgo, así como la frecuencia de sangrado o recidiva durante el período agudo. Finalizado el período agudo con vigilancia y tratamiento por parte de la HAD se siguió a los pacientes en consultas externas de medicina interna, valorando en cada visita las complicaciones a largo plazo: recidiva, síndrome postflebítico (SPF) o exitus. Resultados. Las complicaciones más frecuentes a corto plazo fueron sangrado (3,2 por ciento) y recidiva (7,3 por ciento). Un 18,3 por ciento de los pacientes presentó hepatotoxicidad (aumento de más de 1,5 veces de las transaminasas basales) secundaria a la nadroparina; sin embargo, en todos los casos fue leve y desapareció al retirar la HBPM.Con una media de seguimiento de 15,4 meses, un 16,5 por ciento de los pacientes en total recidivó, un 25,8 por ciento tuvo SPF y 23,7 por ciento de los pacientes murió. La muerte se asoció a tener algún factor de riesgo (32,7 por ciento frente a 7,69 por ciento; p = 0,004), sobre todo a que este factor de riesgo fuese la presencia de un tumor (75 por ciento frente a 12 por ciento; p < 0,001). Conclusiones. La trombosis venosa profunda es una enfermedad con complicaciones frecuentes, tanto en el momento agudo como a largo plazo, pero que se puede tratar de forma segura y eficaz por HAD. Esta enfermedad presenta un elevado riesgo de mortalidad, condicionado sobre todo por su asociación con enfermedades graves (AU)


Assuntos
Pessoa de Meia-Idade , Idoso , Masculino , Feminino , Humanos , Assistência Ambulatorial , Análise de Sobrevida , Nadroparina , Trombose Venosa , Anticoagulantes , Heparina de Baixo Peso Molecular
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