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1.
Biodivers Data J ; 11: e101280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327324

RESUMO

Background: The Gorongosa National Park (Mozambique) is one of the most emblematic protected areas in Africa, well known for its vertebrate biodiversity and restoration ecology efforts following the Mozambican civil war in 1992. The invertebrate biodiversity of Gorongosa National Park is still poorly studied, although the scarce information available indicates the existence of a rich number of species, namely in the case of tiger- and ground-beetles (Coleoptera, Caraboidea). Moreover, the study of arthropod assemblages is key for designing conservation practices since they are potentially accurate biodiversity and ecological indicators. Hence, the diversity assessment of Caraboidea beetles using standardised methodologies is likely to provide a new insight for future conservation planning and help to quantify the effects of climate change in areas identified as vulnerable to anthropogenic pressures, such as the Gorongosa National Park. New information: We report the occurrence of five tiger beetles (Cicindelidae) and 93 ground-beetles (Carabidae) species/morphospecies in Gorongosa National Park from a field survey funded by the ECOASSESS project. Sampling was performed in the four main habitat types present in the Park (miombo tropical forest, mixed dry forest, transitional forest and grasslands) between 25 October and 25 November 2019. In this sampling window, the turnover of Caraboidea species from the dry season to the wet season was recorded for the first time. Twenty-eight species of ground-beetles are new records to Mozambique, including three new subgenera and three new genera. Additional information on species phenology and habitat preferences is also provided.

2.
Br J Pharmacol ; 179(12): 2938-2952, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34978070

RESUMO

BACKGROUND AND PURPOSE: Metabolic and vascular dysfunction are common features of obesity. Aryl hydrocarbon receptor (AhR) regulates lipid metabolism and vascular homeostasis, but whether vascular AhR are activated in obesity or have a protective and/or harmful effects on vascular function in obesity are unknown. Our study addresses whether AhR activation contributes to obesity-associated vascular dysfunction and the mechanisms involved in these AhR effects. EXPERIMENTAL APPROACH: Male AhR KO (Ahr-/- ) and WT mice were fed either control or a HF (high-fat) diet for 10 weeks. Metabolic and inflammatory parameters were measured in serum and adipose tissue. Vascular reactivity (isometric force) was evaluated using a myography. Endothelial NOS (eNOS) and AhR protein expression was determined by western blot, Cyp1A1 and Nos3 gene expression by RT-PCR and.NO production was quantified by DAF fluorescence. KEY RESULTS: HF diet increased total serum HDL and LDL, as well as vascular AhR protein expression and proinflammatory cytokines in the adipose tissue. HF diet decreased endothelium-dependent vasodilation. AhR deletion protected mice from HF diet-induced dyslipidaemia, weight gain and inflammatory processes. HF diet-induced endothelial dysfunction was attenuated in Ahr-/- mice. Vessels from Ahr-/- mice exhibited a greater NO reserve. In cultured endothelial cells, lysophosphatidylcholine (LPC) a major component of LDL and oxidized LDL [oxLDL]) reduced Nos3 gene expression and NO production. Antagonism of the AhR inhibited LPC effects on endothelial cells and induced decreased endothelium-dependent vasodilation. CONCLUSION AND IMPLICATIONS: AhR deletion attenuates HF diet-induced dyslipidaemia and vascular dysfunction by improving eNOS/NO signalling. Targeting AhRs may prevent obesity-associated vascular dysfunction.


Assuntos
Dieta Hiperlipídica , Receptores de Hidrocarboneto Arílico , Animais , Dieta Hiperlipídica/efeitos adversos , Células Endoteliais/metabolismo , Endotélio Vascular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Vasodilatação/fisiologia
3.
PeerJ ; 8: e8084, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31915567

RESUMO

Dietary studies can reveal valuable information on how species exploit their habitats and are of particular importance for insular endemics conservation as these species present higher risk of extinction. Reptiles are often neglected in island systems, principally the ones inhabiting remote areas, therefore little is known on their ecological networks. The Selvagens gecko Tarentola (boettgeri) bischoffi, endemic to the remote and integral reserve of Selvagens Archipelago, is classified as Vulnerable by the Portuguese Red Data Book. Little is known about this gecko's ecology and dietary habits, but it is assumed to be exclusively insectivorous. The diet of the continental Tarentola species was already studied using classical methods. Only two studies have used next-generation sequencing (NGS) techniques for this genus thus far, and very few NGS studies have been employed for reptiles in general. Considering the lack of information on its diet and the conservation interest of the Selvagens gecko, we used morphological and DNA metabarcoding approaches to characterize its diet. The traditional method of morphological identification of prey remains in faecal pellets collected over a longer period was compared with metabarcoding of samples collected during rapid surveys. Molecular results revealed that this species is a generalist, feeding on invertebrate, plant and vertebrate items, whereas the morphological approaches were unable to detect the latter two. These results opened up new questions on the ecological role of the Selvagens gecko that deserves to be further explored, such as the possible predation on seabirds, plant services or trophic competition with the sympatric Madeira lizard Teira dugesii. Metabarcoding identified a greater diversity of dietary items at higher taxonomic resolution, but morphological identification enabled calculation of relative abundances and biomasses of ingested arthropods, and detected a dietary shift on invertebrate preys between seasons. Results of this study highlight the global applicability of rapid metabarcoding surveys for understudied taxa on remote islands that are difficult to access. We recommend using the metabarcoding approach, even if 'speedy' sampling only is possible, but we must highlight that disregarding long-term ecological data may lead to 'hasty' conclusion.

4.
PLoS One ; 13(4): e0195492, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29694360

RESUMO

During the last few centuries oceanic island biodiversity has been drastically modified by human-mediated activities. These changes have led to the increased homogenization of island biota and to a high number of extinctions lending support to the recognition of oceanic islands as major threatspots worldwide. Here, we investigate the impact of habitat changes on the spider and ground beetle assemblages of the native forests of Madeira (Madeira archipelago) and Terceira (Azores archipelago) and evaluate its effects on the relative contribution of rare endemics and introduced species to island biodiversity patterns. We found that the native laurel forest of Madeira supported higher species richness of spiders and ground beetles compared with Terceira, including a much larger proportion of indigenous species, particularly endemics. In Terceira, introduced species are well-represented in both terrestrial arthropod taxa and seem to thrive in native forests as shown by the analysis of species abundance distributions (SAD) and occupancy frequency distributions (OFD). Low abundance range-restricted species in Terceira are mostly introduced species dispersing from neighbouring man-made habitats while in Madeira a large number of true rare endemic species can still be found in the native laurel forest. Further, our comparative analysis shows striking differences in species richness and composition that are due to the geographical and geological particularities of the two islands, but also seem to reflect the differences in the severity of human-mediated impacts between them. The high proportion of introduced species, the virtual absence of rare native species and the finding that the SADs and OFDs of introduced species match the pattern of native species in Terceira suggest the role of man as an important driver of species diversity in oceanic islands and add evidence for an extensive and severe human-induced species loss in the native forests of Terceira.


Assuntos
Besouros , Florestas , Ilhas , Aranhas , Animais , Biodiversidade , Lauraceae , Portugal
5.
Zootaxa ; 3974(3): 401-12, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-26249913

RESUMO

A new species of the genus Domene Fauvel, 1873-D. viriatoi n. sp.-is described from a granitic natural cavity in Serra da Estrela, Portugal. This subterranean species is diagnosed and compared with closely related species from the Iberian endemic subgenus Lathromene Koch, 1938. The external morphology and male genitalia are illustrated and information on the species` ecology is presented. A dichotomic key to the Lathromene species based on the male genitalia is provided. The need to protect the habitat of this species from human disturbance is commented on.


Assuntos
Besouros/anatomia & histologia , Besouros/classificação , Distribuição Animal , Animais , Masculino , Portugal , Especificidade da Espécie
6.
Biodivers Data J ; (2): e1051, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24855443

RESUMO

Madeira island presents a unique spider diversity with a high number of endemic species, many of which are still poorly known. A recent biodiversity survey on the terrestrial arthropods of the native forest, Laurisilva, provided a large set of standardized samples from various patches throughout the island. Out of the fifty two species recorded, approximately 33.3% are Madeiran endemics, many of which had not been collected since their original description. Two new species to science are reported - Ceratinopsis n. sp. and Theridion n. sp. - and the first records of Poecilonetavariegata (Blackwall, 1841) and Tetragnathaintermedia Kulczynski, 1891 are reported for the first time for Madeira island. Considerations on species richness and abundance from different Laurisilva locations are presented, together with distribution maps for endemic species. These results contribute to a better understanding of spider diversity patterns and endemic species distribution in the native forest of Madeira island.

7.
PLoS One ; 8(5): e64591, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23724065

RESUMO

The development in recent years of new beta diversity analytical approaches highlighted valuable information on the different processes structuring ecological communities. A crucial development for the understanding of beta diversity patterns was also its differentiation in two components: species turnover and richness differences. In this study, we evaluate beta diversity patterns of ground beetles from 26 sites in Madeira Island distributed throughout Laurisilva--a relict forest restricted to the Macaronesian archipelagos. We assess how the two components of ground beetle beta diversity (ß(repl)--species turnover and ß(rich)--species richness differences) relate with differences in climate, geography, landscape composition matrix, woody plant species richness and soil characteristics and the relative importance of the effects of these variables at different spatial scales. We sampled 1025 specimens from 31 species, most of which are endemic to Madeira Island. A spatially explicit analysis was used to evaluate the contribution of pure environmental, pure spatial and environmental spatially structured effects on variation in ground beetle species richness and composition. Variation partitioning showed that 31.9% of species turnover (ß(repl)) and 40.7% of species richness variation (ß(rich)) could be explained by the environmental and spatial variables. However, different environmental variables controlled the two types of beta diversity: ß(repl) was influenced by climate, disturbance and soil organic matter content whilst ß(rich) was controlled by altitude and slope. Furthermore, spatial variables, represented through Moran's eigenvector maps, played a significant role in explaining both ß(repl) and ß(rich), suggesting that both dispersal ability and Madeira Island complex orography are crucial for the understanding of beta diversity patterns in this group of beetles.


Assuntos
Biodiversidade , Besouros , Ecossistema , Animais , Meio Ambiente , Geografia , Ilhas , Árvores
8.
Iowa Orthop J ; 27: 85-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17907436

RESUMO

The case of a four-year-old child is described who presented to our institution with cervicothoracic deformity and a two-year history of progressive paraparesis. His past medical history was significant for meningocele which was closed at age two months. Imaging studies revealed severe congenital kyphosis with a hypoplastic T3 vertebra, as well as a tethered filum terminale with a conus lipoma. The spinal cord was found to be severely compressed at the apex of the kyphotic deformity. Discussion is focused on the diagnosis of tethered cord syndrome, and treatment options. In particular, this case required careful thought on the order of events, which followed initial tethered cord release and removal of the conus lipoma, and subsequent kyphectomy and fusion of the upper thoracic spine. A favorable clinical outcome was obtained with complete reversal of the paraparesis.


Assuntos
Neoplasias do Sistema Nervoso Central/complicações , Dura-Máter , Cifose/complicações , Lipoma/complicações , Compressão da Medula Espinal/etiologia , Neoplasias do Sistema Nervoso Central/cirurgia , Pré-Escolar , Humanos , Cifose/congênito , Cifose/diagnóstico por imagem , Cifose/cirurgia , Lipoma/cirurgia , Imageamento por Ressonância Magnética , Masculino , Procedimentos Neurocirúrgicos/métodos , Radiografia , Compressão da Medula Espinal/diagnóstico , Compressão da Medula Espinal/cirurgia , Fusão Vertebral , Vértebras Torácicas/cirurgia
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