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1.
Sci Rep ; 12(1): 14905, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050357

RESUMO

In the Mediterranean Sea, the Strait of Messina (MS) is a very peculiar area, connecting highly different regions and representing a privileged observatory for an early comprehension and assessment of ecosystems shifts. It is hypothesized that the outbreaks observed near the coast of many sites in the Mediterranean Sea may be the result of transport of permanent populations of P. noctiluca in pelagic waters to the coast, caused by specific hydrodynamic conditions. By both visual observations and numerical experiments our objective is twofold: (A) to help clarify whether the basin of the Aeolian Islands Archipelago (AIA), in the Southern Tyrrhenian Sea (STS), may be the site from which large populations of P. noctiluca are transported to the MS, and (B) to evaluate whether the upwelling turbulent system of the MS can be an energetic opportunity for this species. It should offer a rich habitat without jeopardizing the overall survival of the population, that is subject to stranding due to strong currents. Although very different, the two involved ecosystems (AIA and MS ) are complementary for the success of Pelagia noctiluca life cycle. Outputs obtained by coupling the 3D hydrodynamic model (SHYFEM) with a Lagrangian particle tracking model support the hypothesis of a connectivity between these two ecosystems, particularly in the first half of the year, indicating the coastal areas around the AIA as potential optimal source location for Pelagia larval stages. We support the very attractive hypothesis that two connected systems exist, the former one favours Pelagia's reproduction and acts as a nursery and the latter favours its growth due to higher productivity. We speculate that the reproductive population of the AIA is not permanent, but is renewed every year by individuals who have fed and quickly grown in the MS and who are passively transported by downwelling along canyon "corridors".


Assuntos
Dinoflagellida , Cifozoários , Animais , Ecossistema , Humanos , Mar Mediterrâneo
2.
Mar Environ Res ; 54(3-5): 761-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12408647

RESUMO

The aim of this study was to propose a suite of biomarkers (BPMO activity, NADPH-cytocrome c reductase, NADH-ferricyanide reductase. esterases, porphyrins, vitellogenin and zona radiata proteins) and residue levels (organochlorines, PAHs and heavy metals) in the zooplanktonic euphausiid Meganyctiphanes norvegica as a potential multi-disciplinary diagnostic tool for assessment of the health status of the Mediterranean "whale sanctuary". Very little difference in BPMO was detected between sites, with values ranging from 0.75 to 2.68 U.A.F./mg prot/h. On the other hand larger differences between sites were found for reductase activities. Esterases (AChE), porphyrins (Copro-, Uro-, Proto-porphyrins) vitellogenin and zona radiata proteins were also detectable in this zooplanctonic species. Hg showed mean levels of 0.141 ppm d.w., Cd 0.119 ppm d.w. and Pb 0.496 ppm d.w. Total PAHs ranged from 860.7 to 5,037.9 ng/g d.w., carcinogenic PAHs from 40.3 to 141.7 ng/g d.w., HCB from 3.5 to 11.6 ng/g d.w., DDTs from 45.3 to 163.2 ng/g d.w. and the PCBs from 84.6 to 210.2 ng/g d.w.


Assuntos
Biomarcadores/análise , Monitoramento Ambiental/métodos , Esterases/análise , Euphausiacea/fisiologia , Poluentes Químicos da Água/efeitos adversos , Animais , Esterases/biossíntese , Hidrocarbonetos Clorados , Inseticidas/efeitos adversos , Inseticidas/análise , Região do Mediterrâneo , Metais Pesados/efeitos adversos , Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Vitelogeninas/análise , Vitelogeninas/biossíntese , Poluentes Químicos da Água/análise , Baleias
3.
Mar Environ Res ; 54(3-5): 799-804, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12408653

RESUMO

Zooplankton are an essential component of the marine and estuarine food chains. The ecotoxicological risk to zooplanktonic communities, estimated through the use of the biomarkers, can be used as an early warning signal of a potential alteration of the ecosystem health. The aim of this project was to evaluate the potential use of several biomarkers (esterases, mixed function oxidases, porphyrins) in zooplanktonic organisms. The acetylcholinesterase activity (AChE) was determined in homogenates of whole organisms of 10 different zooplanktonic crustaceans. Mean activity of AChE was 10.05 micromol/min/g for Acartia margalefi; 3.30 for Acartia latisetosa; 79.70 for Siriella clausi; 49.97 for Diamysis bahirensis; 7.48 for Siriella armata; 14.20 for Mysidopsis gibbosa; 4.49 for Euphausia crystallorophias; 1.66 for Euphausia superba; 2.74 for Streetsia challengeri; 13.26 for Meganycthiphanes norvegica. The species moreover showed a linear increase in enzyme activity in relation to the increase in sample concentration. The key result of this study concerns the different AChE activity basal values of the crustaceans' different species.


Assuntos
Acetilcolinesterase/farmacologia , Biomarcadores/análise , Crustáceos/fisiologia , Zooplâncton/fisiologia , Acetilcolinesterase/análise , Animais , Monitoramento Ambiental , Valores de Referência
4.
Mar Pollut Bull ; 42(9): 745-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11585067

RESUMO

Zooplankton is an essential component of the food chains of marine and brackish environments. Ecotoxicological risk to zooplankton, evaluated by the biomarker approach, can be used as an early warning signal of risk to the health of marine ecosystems. The aim of this project is to evaluate the application of certain biomarkers in zooplankton. In the present paper, laboratory and field studies were performed with the copepods Acartia margalefi, Acartia latisetosa and the mysid Siriella clausi. Acetylcholinesterase activity (AChE) was determined in homogenates of whole organisms. Mean AChE activity was 10.05 micromol min g(-1) for A. margalefi, 3.30 micromol min g(-1) for A. latisetosa and 79.70 micromol min g(-1) for S. clausi. A. margalefi and S. clausi also showed a linear increase in enzyme activity with increasing concentrations of samples. Preliminary laboratory work was also carried out with specimens of A. latisetosa, which were exposed to an organophosphorus insecticide (parathion). Moderate inhibition of AChE (19%) with respect to controls was observed. AChE activities were two orders of magnitude higher in the zooplankton than in hemolymph samples of the decapod Carcinus aestuarii (Fossi et al., 1996) indicating that these species have a high metabolic rate, which makes them suitable for biomarker studies.


Assuntos
Acetilcolinesterase/metabolismo , Crustáceos/enzimologia , Monitoramento Ambiental/métodos , Zooplâncton/enzimologia , Animais , Metabolismo Basal , Biomarcadores , Cadeia Alimentar , Água do Mar , Poluentes Químicos da Água/metabolismo
5.
Thorax ; 45(10): 771-3, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2247870

RESUMO

A simple non-bronchoscopic bronchoalveolar lavage method was used in 30 patients with the acquired immunodeficiency syndrome undergoing assisted ventilation for respiratory failure. A modified Argyle Levin stomach tube was passed via the endotracheal tube and lavage performed. The lavage was well tolerated and performed quickly and easily, required little training, and had a high degree of sensitivity (73%--a diagnosis in 22 of the 30 cases).


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Líquido da Lavagem Broncoalveolar/diagnóstico , Infecções Oportunistas/diagnóstico , Pneumonia/diagnóstico , Humanos , Intubação Intratraqueal , Infecções Oportunistas/complicações , Pneumonia/complicações , Respiração Artificial , Insuficiência Respiratória/complicações , Insuficiência Respiratória/terapia , Irrigação Terapêutica/instrumentação
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