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1.
Proc Biol Sci ; 288(1951): 20210458, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34004134

RESUMO

How far do marine larvae disperse in the ocean? Decades of population genetic studies have revealed generally low levels of genetic structure at large spatial scales (hundreds of kilometres). Yet this result, typically based on discrete sampling designs, does not necessarily imply extensive dispersal. Here, we adopt a continuous sampling strategy along 950 km of coast in the northwestern Mediterranean Sea to address this question in four species. In line with expectations, we observe weak genetic structure at a large spatial scale. Nevertheless, our continuous sampling strategy uncovers a pattern of isolation by distance at small spatial scales (few tens of kilometres) in two species. Individual-based simulations indicate that this signal is an expected signature of restricted dispersal. At the other extreme of the connectivity spectrum, two pairs of individuals that are closely related genetically were found more than 290 km apart, indicating long-distance dispersal. Such a combination of restricted dispersal with rare long-distance dispersal events is supported by a high-resolution biophysical model of larval dispersal in the study area, and we posit that it may be common in marine species. Our results bridge population genetic studies with direct dispersal studies and have implications for the design of marine reserve networks.


Assuntos
Fluxo Gênico , Genética Populacional , Animais , Humanos , Larva/genética , Mar Mediterrâneo
2.
Mar Environ Res ; 92: 23-34, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24008004

RESUMO

Population connectivity scales are important tools to achieve a mechanistic understanding of the factors regulating the abundance and distribution of marine populations and therefore support conservation actions to manage fisheries and stocks. We used 10 microsatellites markers on mullets' samples across the Spanish coast to determine the spatial scale of gene flow as well as the origin of post-larvae caught inside two MPAs. Population structure varied from complete homogeneity for Mullus barbatus, to high spatial variability in Mullus surmuletus samples. Differential habitat utilization by species, geomorphological features and oceanographic patterns are discussed as potential causes of patterns observed. Although we were unable to verify the origin of most post-larvae caught inside MPAs we suggest that they may act as genetic reservoirs due to high heterozigosity levels found in adult specimens inside (M. surmuletus) and nearby (both) them. Our results indicate that early life history traits (i.e. larvae) may not be the only determinant on species dispersal capability, suggesting that other mechanisms such as fine scale adult or juvenile movement may have been underestimated as promoting population connectivity.


Assuntos
Variação Genética , Genética Populacional , Perciformes/genética , Animais , Fluxo Gênico , Especiação Genética , Heterozigoto , Larva , Mar Mediterrâneo , Repetições de Microssatélites , Dinâmica Populacional , Espanha , Simpatria
3.
Mar Environ Res ; 79: 48-54, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22717344

RESUMO

The effect of intracoelomic tagging of an acoustic telemetry transmitter (1.65% ratio of tag mass in the air to fish mass in the air) on behavioral (food intake and locomotor activity) and physiological (blood glucose and plasma cortisol) parameters of gilthead seabream was investigated. To this end, fish (289 ± 53 g, mean ± SD) were divided into 3 experimental groups: control (C), transmitter (T, inserted surgically) and sham group (S, subjected to surgery but without transmitter insertion). Blood was extracted during surgery and 9 days later. Throughout the trial, fish were fed by means of self-feeders and locomotor activity was measured by means of an infrared photocell. Two days after the first manipulation, a significant decrease in food intake could be observed in all the experimental groups. The fact that food intake was not affected after the second manipulation seems to indicate that a learning process took place for handling. The rhythmicity of feeding and locomotor activity was not affected by handling in any experimental group. However, group T showed increased plasma cortisol levels 9 days after surgery. In conclusion, while most behavioral parameters were not affected by handling, the plasma cortisol levels of seabream 9 days after insertion of the transmitter indicated a physiological impact that should be taken into account in long-term radiotracking studies, since such an operation could have negative effects on wild individuals after the end of the tracking experiments.


Assuntos
Comportamento Animal , Dourada/fisiologia , Estresse Fisiológico , Telemetria/instrumentação , Animais , Ritmo Circadiano , Ingestão de Alimentos/fisiologia , Manobra Psicológica , Hidrocortisona/sangue , Atividade Motora/fisiologia , Telemetria/efeitos adversos
4.
Mol Ecol ; 20(9): 1964-75, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21463375

RESUMO

We assessed the genetic structure of populations of the widely distributed sea cucumber Holothuria (Holothuria) mammata Grube, 1840, and investigated the effects of marine barriers to gene flow and historical processes. Several potential genetic breaks were considered, which would separate the Atlantic and Mediterranean basins, the isolated Macaronesian Islands from the other locations analysed, and the Western Mediterranean and Aegean Sea (Eastern Mediterranean). We analysed mitochondrial 16S and COI gene sequences from 177 individuals from four Atlantic locations and four Mediterranean locations. Haplotype diversity was high (H=0.9307 for 16S and 0.9203 for COI), and the haplotypes were closely related (π=0.0058 for 16S and 0.0071 for COI). The lowest genetic diversities were found in the Aegean Sea population. Our results showed that the COI gene was more variable and more useful for the detection of population structure than the 16S gene. The distribution of mtDNA haplotypes, the pairwise F(ST) values and the results of exact tests and amova revealed: (i) a significant genetic break between the population in the Aegean Sea and those in the other locations, as supported by both mitochondrial genes, and (ii) weak differentiation of the Canary and Azores Islands from the other populations; however, the populations from the Macaronesian Islands, Algarve and West Mediterranean could be considered to be a panmictic metapopulation. Isolation by distance was not identified in H. (H.) mammata. Historical events behind the observed findings, together with the current oceanographic patterns, were proposed and discussed as the main factors that determine the population structure and genetic signature of H. (H.) mammata.


Assuntos
Holothuria/genética , Filogeografia , Animais , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fluxo Gênico , Variação Genética , Haplótipos/genética , Mar Mediterrâneo , Oceanografia , Análise de Sequência de DNA
5.
Ecol Appl ; 20(3): 830-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20437967

RESUMO

Marine reserves are assumed to protect a wide range of species from deleterious effects stemming from exploitation. However, some species, due to their ecological characteristics, may not respond positively to protection. Very little is known about the effects of life history and ecological traits (e.g., mobility, growth, and habitat) on responses of fish species to marine reserves. Using 40 data sets from 12 European marine reserves, we show that there is significant variation in the response of different species of fish to protection and that this heterogeneity can be explained, in part, by differences in their traits. Densities of targeted size-classes of commercial species were greater in protected than unprotected areas. This effect of protection increased as the maximum body size of the targeted species increased, and it was greater for species that were not obligate schoolers. However, contrary to previous theoretical findings, even mobile species with wide home ranges benefited from protection: the effect of protection was at least as strong for mobile species as it was for sedentary ones. Noncommercial bycatch and unexploited species rarely responded to protection, and when they did (in the case of unexploited bentho-pelagic species), they exhibited the opposite response: their densities were lower inside reserves. The use of marine reserves for marine conservation and fisheries management implies that they should ensure protection for a wide range of species with different life-history and ecological traits. Our results suggest this is not the case, and instead that effects vary with economic value, body size, habitat, depth range, and schooling behavior.


Assuntos
Comportamento Animal , Conservação dos Recursos Naturais , Peixes , Animais , Tamanho Corporal , Ecossistema , Europa (Continente) , Pesqueiros , Modelos Biológicos , Densidade Demográfica , Territorialidade
6.
Mar Environ Res ; 65(4): 291-314, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18187188

RESUMO

Although benthic macrophytes must be considered in monitoring programs to establish the ecological status of transitional and coastal waters in the European Union, the patterns of variability in species composition of macrophyte assemblages in Mediterranean coastal lagoons has scarcely been studied. In this work the spatial (both vertical and horizontal) and seasonal dynamics of macrophyte assemblages in a coastal lagoon (Mar Menor) are compared with those of open coastal assemblages in the SW Mediterranean to analyze any biological variability in lagoon assemblages and the factors that determine such variability. Different assemblages, characterized by well defined groups of species, can be described according to their isolation from the open sea and the type of substratum; at the same time, a vertical zonation pattern, similar to that found in all marine communities but more compressed, exists. This implies that when applying the EU Water Framework Directive or assessing environmental impact, a lagoon should not be considered spatially uniform and unique unit but as a mosaic of assemblages.


Assuntos
Biodiversidade , Água Doce/microbiologia , Estações do Ano , Água do Mar/microbiologia , Biomassa , Eucariotos/isolamento & purificação , Mar Mediterrâneo , Filogenia , Plantas , Densidade Demográfica , Temperatura , Movimentos da Água
7.
Patol. apar. locomot. Fund. Mapfre Med ; 5(supl.2): 91-96, 2007. ilus
Artigo em Es | IBECS | ID: ibc-057023

RESUMO

Las fracturas de radio distal y, en concreto, las de alta energía, se han asociado a múltiples complicaciones. A pesar de que muchas son inherentes a la fractura, el uso de fijación interna o externa, o incluso el yeso de parís, incrementa el riesgo de complicaciones. La reducción cerrada y el vendaje enyesado aumenta la incidencia de consolidación viciosa, artritis y síndrome del tunel carpiano tardío, pero disminuye el riesgo de todas las complicaciones relacionadas con la cirugía. La fijación interna o externa aumenta el riesgo de infección profunda, irritación tendinosa y lesiones nerviosas. Se han descrito complicaciones específicas a cada tipo de tratamiento. El conocimiento de estas puede ayudar al cirujano a evitarlas y prevenirlas, y, consecuentemente, mejorar el resultado de la fractura. En la elección del tratamiento a aplicar, el cirujano no debe olvidar que el resultado funcional no depende sólo del tipo de fractura sino también del tratamiento y de la correcta ejecución del mismo. Para evitar y prevenir complicaciones se aconseja un estrecho seguimiento del paciente


Fractures of distal radius, and, overall, high energy fractures, have been related to many complications. Although many of these are directly related to the fracture itself, the use of internal or external fixation, even a plaster of paris, adds an increased risk of complications. Closed reduction and casting increase malunion, arthritis and late carpal tunnel syndrome, but decrease the risk of surgical complications. Internal or external fixation may increase risk of deep infection, tendon irritation and nerve injuries. Specific treatment related complications have been reported. Knowledge of these may help surgeons in avoidance and prevention of them, and, consequently, improve fracture outcome. When selecting the best treatment, the surgeon must not forget that a functional outcome depends not only on the fracture pattern but on the treatment itself and its correct perform. Moreover, a close follow-up in order to avoid and prevent complications is also advised


Assuntos
Humanos , Fraturas do Rádio/terapia , Procedimentos Ortopédicos/efeitos adversos , Complicações Pós-Operatórias , Fraturas não Consolidadas/complicações , Fixação de Fratura/efeitos adversos , Dispositivos de Fixação Ortopédica/efeitos adversos , Transplante Ósseo/efeitos adversos
8.
Mar Pollut Bull ; 52(7): 817-29, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17165196

RESUMO

Assessing the ecological status, a concept implemented in the European Water Framework Directive [EC, 2000. Directive of the European Parliament and of the Council 2000/60/EC establishing a framework for community action in the field of water policy PE-CONS 3639/1/00, p. 72], requires the application of methods capable of distinguishing different levels of ecological quality. The Average Taxonomic Distinctness has been used as tool in this context, and we tested the robustness of Taxonomic Distinctness measures applying it in different scenarios (estuarine eutrophication, organic pollution, and re-colonisation after physical disturbance), analysing simultaneously its compliance to other types of ecological indicators. Results show that, in most of the case studies, only Total Taxonomic Distinctness was relatively satisfactory in discriminating between disturbed situations. Other Taxonomic Distinctness measures have not proved to be more sensitive than other ecological indicators (Shannon-Wiener, Margalef, and Eco-Exergy indices). Therefore, this approach does not seem to be particularly helpful in assessing systems' ecological status with regard to the WFD implementation.


Assuntos
Conservação dos Recursos Naturais , Ecologia/estatística & dados numéricos , Monitoramento Ambiental , Modelos Estatísticos , Animais , Biodiversidade , Ecologia/métodos , Geografia , Biologia Marinha/estatística & dados numéricos , Portugal , Água do Mar , Espanha , Fatores de Tempo
9.
Mar Pollut Bull ; 53(1-4): 107-20, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16253291

RESUMO

The benthic fish assemblage of the Mar Menor consisted of 37 species. Dominant species are: Gobius cobitis, Lipophrys pavo and Tripterygion tripteronotus on infralittoral rocks; Pomatoschistus marmoratus, Callionymus pussillus, Callionymus risso and Solea vulgaris on sandy bottoms and Gobius niger, Syngnathus abaster, Hippocampus ramulosus and Symphodus cinereus on Cymodocea nodosa-Caulerpa prolifera mixed beds. From 1985 to 1989 tourist development has led to the creation of new beaches and the installation of artificial rocky structures for retaining sediments. Dredging for the extraction of sand and subsequent pumping altered sediment characteristics causing a real stress leading to the substitution of typical sandy bottoms communities with Cymodocea nodosa by Caulerpa prolifera communities on mud. Soft bottom fish assemblages responded to changes in vegetation cover and substratum characteristics mainly changing the species composition, while artificial hard substrata contain a similar fish community than natural ones, harbouring even richer and more diverse assemblages. This positive effect of breakwaters should not obscure their likely negative effects on hydrodynamics and the subsequent changes of sediment quality and vegetation cover on the breakwaters' area of influence.


Assuntos
Biodiversidade , Ecossistema , Monitoramento Ambiental/métodos , Peixes/crescimento & desenvolvimento , Sedimentos Geológicos/análise , Animais , Praias , Humanos , Dinâmica Populacional , Espanha , Especificidade da Espécie , Movimentos da Água
10.
Mar Pollut Bull ; 52(2): 162-74, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16216282

RESUMO

Assessing the ecological status, a concept implemented in the European Water Framework Directive [Directive of the European Parliament and of the Council 2000/60/EC establishing a framework for community action in the field of water policy PE-CONS 3639/1/00, 72 p.], requires the application of methods capable of distinguishing different levels of ecological quality. Somerfield and Clarke [Marine Environmental Research 43 (2003) 145-156] proposed Average Taxonomic Distinctness to be used as tool in this context. We tested the robustness of Taxonomic Distinctness measures applying it in different scenarios (estuarine eutrophication, organic pollution, and re-colonisation after physical disturbance), analysing simultaneously its compliance to other types of ecological indicators. Results show that, in most of the case studies, only Total Taxonomic Distinctness was relatively satisfactory in discriminating between disturbed situations. Other Taxonomic Distinctness measures have not proved to be more sensitive than other ecological indicators (Shannon-Wiener, Margalef, and Eco-Exergy indices). Therefore, this approach does not seem to be particularly helpful in assessing systems' ecological status with regard to the WFD implementation.


Assuntos
Biodiversidade , Classificação/métodos , Conservação dos Recursos Naturais , Ecologia/estatística & dados numéricos , Monitoramento Ambiental , Animais , Ecologia/métodos , Biologia Marinha/estatística & dados numéricos , Portugal , Água do Mar , Fatores de Tempo
11.
Rev. ortop. traumatol. (Madr., Ed. impr.) ; 48(1): 49-56, ene. 2004. ilus
Artigo em Es | IBECS | ID: ibc-29476

RESUMO

Se ha realizado una actualización sobre el tratamiento del síndrome subacromial en el hombro comparando la cirugía abierta, la cirugía artroscópica y técnicas combinadas para realizar la acromioplastia anterior. El artículo se ha centrado en los estadios II y III de Neer, y en las roturas parciales del manguito rotador, que no impliquen una disminución de fuerza de la extremidad y se objetive una causa extrínseca de la rotura parcial (acromion II-III). También se incluye la tendinitis calcificante del manguito.La elección de la técnica quirúrgica debe tener en cuenta la edad, los requerimientos del hombro a tratar, la bóveda subacromial, la patología lesional del manguito rotador y el estadio evolutivo de la misma (AU)


Assuntos
Humanos , Procedimentos Ortopédicos/métodos , Manguito Rotador/cirurgia , Síndrome de Colisão do Ombro/cirurgia , Artroscopia/métodos
12.
Clin Endocrinol (Oxf) ; 52(2): 159-64, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10671942

RESUMO

BACKGROUND: A direct relationship between body mass index (BMI), visceral adipose tissue, insulin levels and growth hormone-binding protein (GHBP) activity has consistently been reported. It was recently described that GHBP directly depends on serum leptin levels. Since leptin co-varies with insulin secretion and/or sensitivity, we aimed to study the influence of these variables on plasma GHBP activity. SUBJECTS: In order to isolate the effects of obesity per se from those of insulin secretion, three groups of subjects were prospectively studied: 14 lean, 10 obese and nine obese subjects with glucose intolerance. MEASUREMENTS: The percentage of body fat was measured through bioelectric impedance. Insulin sensitivity and secretion were determined through a frequently sampled intravenous glucose tolerance test with minimal model analysis. Serum leptin was measured by radioimmunoassay. GHBP activity was determined by the high performance liquid chromatography-gel filtration method. RESULTS: Plasma GHBP activity was found to correlate with BMI (r = 0. 65, P < 0.0001), fat mass (r = 0.51, P = 0.003), waist circumference (r = 0.64, P < 0.0001), waist-to-hip ratio (r = 0.42, P = 0.01), insulin sensitivity (SI, r = - 0.61, P = 0.0001), insulin secretion (expressed as the acute insulin response to intravenous glucose, AIRg) (r = 0.48, P = 0.006) and leptin concentration (r = 0.49, P = 0.004). The associations with SI (r = - 0.42, P = 0.02) and AIRg (r = 0.38, P = 0.03) persisted even after controlling for fat mass. Since insulin secretion and insulin sensitivity usually covary in glucose tolerant subjects (an increased insulin secretion is necessary to compensate a decreased insulin sensitivity), we constructed a multiple linear regression to predict GHBP activity. In this model, SI (P = 0.005), AIRg (P = 0.02) and SD score-leptin (P = 0.03) independently contributed to 34, 10 and 8% of the variability in serum GHBP activity. CONCLUSIONS: Our results suggest that plasma GHBP activity is simultaneouslly influenced by insulin secretion and sensitivity and leptin. Perhaps leptin, through increased insulin secretion, might induce GHBP/GH secretion, explaining the normal to high insulin-like growth factor (IGF)-I levels found in overnutrition.


Assuntos
Proteínas de Transporte/sangue , Intolerância à Glucose , Insulina/metabolismo , Leptina/sangue , Obesidade/sangue , Adulto , Constituição Corporal/fisiologia , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Secreção de Insulina , Modelos Lineares , Masculino , Estudos Prospectivos
13.
Rev. bras. ortop ; 34(5): 355-360, maio 1999. ilus, graf
Artigo em Português | LILACS | ID: lil-360950

RESUMO

O presente trabalho apresenta estudo experimental realizado em 65 coelhos albinos da Nova Zelândia divididos em dois grupos. Os animais do grupo I foram submetidos a cirurgia para realização de cavidade em nível metafisário do fêmur e tíbia, sem qualquer tipo de preenchimento desta. Nos animais do grupo 11 realizou-se a mesma intervenção, preenchendo-se cada cavidade com duas pastilhas de gesso impregnadas de gentamicina. Durante o pós-operatório e até o sacrifício dos animais, foram realizados controles bioquímicos, radiográficos e histológicos. O tratamento estatístico dos resultados foi realizado pelos testes de Wilcoxon e t de Student, com significância estatística de p < 0,05. Comprovou-se a reabsorção completa das pastilhas implantadas, produzindo a regeneração óssea da cavidade.


Assuntos
Animais , Transplante Ósseo , Sulfato de Cálcio , Gentamicinas , Fêmur , Tíbia
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