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1.
Mar Pollut Bull ; 207: 116901, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39217872

RESUMO

One of the world's crucial areas for crude oil exploration and extraction is the southern Gulf of Mexico, where Terminos Lagoon (TL) is located. Sediments from the TL region were used to assess the spatial patterns, origins, and ecotoxicological risks associated with 16 priority polycyclic aromatic hydrocarbons (PAHs; 3.1-248.9 ng⸳g-1 dry weight basis, dw) and trace metals (Ni = 11.0-104.0 mg⸳kg-1; V = 2.0-35.0 mg⸳kg-1 dw) linked to anthropogenic activities. Although origin indices based on PAHs and metals concentrations indicate no crude oil pollution in the region, sources of pyrogenic PAHs were identified. A chemometric approach demonstrated associations between organic matter and PAHs, and that metal accumulation depends mostly by the input of lithogenic materials. Ecotoxicological risk estimations showed a higher risk of possible adverse effects in sites near swamps and mangrove zones, highlighting the need of future monitoring. This study provides a reference for policymakers to conserve Mexico's largest coastal lagoon and other oil-impacted coastal areas worldwide.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Níquel , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Vanádio , Poluentes Químicos da Água , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Golfo do México , Poluentes Químicos da Água/análise , Vanádio/análise , Níquel/análise , Petróleo/análise , Poluição por Petróleo/análise
2.
Mar Pollut Bull ; 185(Pt A): 114260, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36368083

RESUMO

Cadmium is a toxic element and its effects are well understood for human health, but its biogeochemical behaviour is still poorly studied and understood in natural ecosystems. This work addresses knowledge gaps concerning its presence, biogeochemical behaviour and impacts in mangrove ecosystems. Through geochemical data and multivariate analysis (i.e., factor and cluster analysis) of data from mangroves of Isla del Carmen, one of the largest extents in Mexico we explored the biogeochemical behaviour of Cd, a potentially toxic element, to identify its anthropogenic sources and interactions with sediments. Pollution indices, including enrichment factor (EF), geo-accumulation index (Igeo), sediment quality guidelines (SQG) and toxicological studies were used to assess the biological impacts of Cd and infer the natural levels tolerated by mangrove trees that form the basis of this natural ecosystem. Our results highlighted that Cd accumulation is driven by interactions between organic matter (OM), sulphur and fine particles; whereas enrichment factor showed values of 6.9 (EF) and 3.5 (EF) associated with point sources and ranged between 2 and 2.9 (EF) in relation to non-point sources. Finally, our geochemical approach revealed that Cd enrichment originates from urban activities and from the poor management of urban residuals.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Humanos , Sedimentos Geológicos/análise , Metais Pesados/análise , Cádmio/análise , Monitoramento Ambiental , Ecossistema , Poluentes Químicos da Água/análise , Inquéritos e Questionários , Medição de Risco
3.
Sci Total Environ ; 810: 152309, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34910948

RESUMO

Mangrove ecosystems worldwide have been affected by anthropogenic activities that modify natural conditions and supply trace elements that affect mangrove health and development. In order to gain a better understanding of these ecosystems, and assess the influence of physicochemical (granulometry, pH, salinity and ORP) and geochemical variables (concentrations of V, Cr, Co, Ni, Cu, Zn, Pb, Rb, Sr and Zr) on mangrove phenology, we combined field and satellite derived remotely sensed data. Phenology metrics in combination with Generalized Additive Models showed that start of the season was strongly influenced by Pb and Cu pollution as well as salinity and pH, with a large percentage of deviance explained (92.10%) by the model. Start of season exhibited non-linear delays as a response to pollution. Other phenology parameters such as the length of season, timing of the peak of season, and growth peak also indicated responses to both trace elements and physicochemical and geochemical variables, with percentages of deviance explained by the models ranging between 33.90% and 97.70%. While the peak of season showed delays as a response to increased pH and decreased salinity, growth peak exhibited a non-linear decrease as a response to increased Sr concentrations. These results suggest that trace element pollution is likely to lead to altered phenological patterns in mangroves.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Efeitos Antropogênicos , Ecossistema , Monitoramento Ambiental , Poluição Ambiental , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 730: 138643, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32402958

RESUMO

The petrochemical industry and urban activities are widely recognized worldwide as a source of pollution to mangrove environments. They can supply pollutants such as trace elements that can modify the ecosystem structure and associated services, as well as human populations. Through geochemical data, multivariate statistical analysis and pollution indices such as the enrichment factor (EF), geo-accumulation index (Igeo), adverse effect index (AEI) and the pollution load index (PLI), we evaluated the factors that control trace element distribution, punctual sources and determined the pollution level of sediments and their potential biological impact in the mangrove ecosystem of Isla del Carmen, Mexico. The factor and cluster analysis highlighted that the distribution of trace elements is influenced by the mineralogy, texture as well as urban derived sources. The pollution indices showed values in the punctual sources from the urban area of EF > 10, Igeo > 3, AEI > 3, PLI > 1 by Cu, Zn and Pb. Finally, the results revealed that mangroves from Isla del Carmen has a major influence from urban activities and natural sources rather than oil industry and also indicate a degraded environment as a result of anthropogenic activities that could have knock-on effect for human health if polluted marine organisms derived from the urban mangroves are consumed. CAPSULE ABSTRACT: Surface sediments show the influence of point sources on selected trace element concentrations correlated with human activities within the mangroves of Isla del Carmen, Mexico.


Assuntos
Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Metais Pesados , México , Óleos , Medição de Risco , Oligoelementos , Poluentes Químicos da Água
5.
PLoS One ; 6(2): e16686, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21364984

RESUMO

Human immunodeficiency virus (HIV)-1 encoded Rev is essential for export from the nucleus to the cytoplasm, of unspliced and singly spliced transcripts coding for structural and nonstructural viral proteins. This process is spatially and temporally coordinated resulting from the interactions between cellular and viral proteins. Here we examined the effects of the sub-cellular localization and dynamics of Rev on the efficiency of nucleocytoplasmic transport of HIV-1 Gag transcripts and virus particle production. Using confocal microscopy and fluorescence recovery after bleaching (FRAP), we report that NF90ctv, a cellular protein involved in Rev function, alters both the sub-cellular localization and dynamics of Rev in vivo, which drastically affects the accumulation of the viral protein p24. The CRM1-dependent nuclear export of Gag mRNA linked to the Rev Response Element (RRE) is dependent on specific domains of the NF90ctv protein. Taken together, our results demonstrate that the appropriate intracellular localization and dynamics of Rev could regulate Gag assembly and HIV-1 replication.


Assuntos
Infecções por HIV/virologia , HIV-1/metabolismo , HIV-1/fisiologia , Proteínas do Fator Nuclear 90/fisiologia , Produtos do Gene rev do Vírus da Imunodeficiência Humana/metabolismo , Células Cultivadas , Recuperação de Fluorescência Após Fotodegradação , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/fisiologia , Infecções por HIV/metabolismo , Células HeLa , Humanos , Proteínas do Fator Nuclear 90/química , Proteínas do Fator Nuclear 90/genética , Proteínas do Fator Nuclear 90/metabolismo , Estrutura Terciária de Proteína/genética , Estrutura Terciária de Proteína/fisiologia , Transporte Proteico/fisiologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/fisiologia , Distribuição Tecidual , Vírion/metabolismo , Vírion/fisiologia , Montagem de Vírus/fisiologia , Replicação Viral/genética , Replicação Viral/fisiologia , Produtos do Gene rev do Vírus da Imunodeficiência Humana/genética , Produtos do Gene rev do Vírus da Imunodeficiência Humana/fisiologia
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