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1.
Sci Rep ; 5: 12505, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26216526

RESUMO

Posidonia oceanica meadows are declining at alarming rates due to climate change and human activities. Although P. oceanica is considered the most important and well-studied seagrass species of the Mediterranean Sea, to date there has been a limited effort to combine all the spatial information available and provide a complete distribution of meadows across the basin. The aim of this work is to provide a fine-scale assessment of (i) the current and historical known distribution of P. oceanica, (ii) the total area of meadows and (iii) the magnitude of regressive phenomena in the last decades. The outcomes showed the current spatial distribution of P. oceanica, covering a known area of 1,224,707 ha, and highlighted the lack of relevant data in part of the basin (21,471 linear km of coastline). The estimated regression of meadows amounted to 34% in the last 50 years, showing that this generalised phenomenon had to be mainly ascribed to cumulative effects of multiple local stressors. Our results highlighted the importance of enforcing surveys to assess the status and prioritize areas where cost-effective schemes for threats reduction, capable of reversing present patterns of change and ensuring P. oceanica persistence at Mediterranean scale, could be implemented.


Assuntos
Poaceae/crescimento & desenvolvimento , Mudança Climática , Mar Mediterrâneo
2.
PLoS One ; 10(3): e0119590, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785737

RESUMO

The identification of nursery grounds and other essential fish habitats of exploited stocks is a key requirement for the development of spatial conservation planning aimed at reducing the adverse impact of fishing on the exploited populations and ecosystems. The reduction in juvenile mortality is particularly relevant in the Mediterranean and is considered as one of the main prerequisites for the future sustainability of trawl fisheries. The distribution of nursery areas of 11 important commercial species of demersal fish and shellfish was analysed in the European Union Mediterranean waters using time series of bottom trawl survey data with the aim of identifying the most persistent recruitment areas. A high interspecific spatial overlap between nursery areas was mainly found along the shelf break of many different sectors of the Northern Mediterranean indicating a high potential for the implementation of conservation measures. Overlap of the nursery grounds with existing spatial fisheries management measures and trawl fisheries restricted areas was also investigated. Spatial analyses revealed considerable variation depending on species and associated habitat/depth preferences with increased protection seen in coastal nurseries and minimal protection seen for deeper nurseries (e.g. Parapenaeus longirostris 6%). This is partly attributed to existing environmental policy instruments (e.g. Habitats Directive and Mediterranean Regulation EC 1967/2006) aiming at minimising impacts on coastal priority habitats such as seagrass, coralligenous and maerl beds. The new knowledge on the distribution and persistence of demersal nurseries provided in this study can support the application of spatial conservation measures, such as the designation of no-take Marine Protected Areas in EU Mediterranean waters and their inclusion in a conservation network. The establishment of no-take zones will be consistent with the objectives of the Common Fisheries Policy applying the ecosystem approach to fisheries management and with the requirements of the Marine Strategy Framework Directive to maintain or achieve seafloor integrity and good environmental status.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Peixes/fisiologia , Cooperação Internacional/legislação & jurisprudência , Animais , Biodiversidade , Conservação dos Recursos Naturais/economia , Ecossistema , Europa (Continente) , Feminino , Masculino , Mar Mediterrâneo , Dinâmica Populacional
3.
Clin Cancer Res ; 8(7): 2149-56, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12114415

RESUMO

PURPOSE: Pyrazoloacridine (PZA) is an investigational nucleic acid binding agent that inhibits the activity of topoisomerases I and II through a mechanism distinct from other topoisomerase poisons. PZA shows schedule-independent cytotoxicity against tumor cells, whereas host toxicity is greater with shorter infusions. We assessed the clinical toxicities and pharmacologic effects of PZA given as a 24-h i.v. infusion weekly for 3 of 4 weeks. EXPERIMENTAL DESIGN: Thirty-two adult patients with solid tumors received PZA at five dose levels (100-351 mg/m(2)). Plasma samples were obtained at the end of the PZA infusion at all of the dose levels, with extended sampling in a cohort treated at the recommended dose. RESULTS: Dose-limiting granulocytopenia and mucositis occurred in 2 of 6 patients at 351 mg/m(2), but lower doses were well tolerated. No responses were seen, but 28% had stable disease for > or =3 months. Plasma levels strongly correlated with the degree of granulocytopenia. Extended pharmacokinetics in 7 patients treated with 281 mg/m(2) indicated the following averages: maximum plasma level, 1.6 microM; area under the plasma concentration-time curve, 56 microM.h; terminal half-life, 27 h; urinary recovery, 17% over 72 h. DNA fragmentation in post-PZA bone marrow mononuclear cells was seen in 9 of 28 samples (all at > or =281 mg/m(2)). CONCLUSIONS: Unlike other schedules of PZA, neurotoxicity and thrombocytopenia were not problematic with a weekly 24-h infusion of PZA. The recommended Phase II dose is 281 mg/m(2), which was well tolerated. Both end of infusion plasma levels and presence of DNA damage correlated with granulocyte toxicity.


Assuntos
Acridinas/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Pirazóis/administração & dosagem , Acridinas/efeitos adversos , Acridinas/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Agranulocitose/induzido quimicamente , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Apoptose , Esquema de Medicação , Feminino , Gastroenteropatias/induzido quimicamente , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Pirazóis/efeitos adversos , Pirazóis/farmacocinética
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