Mostrando recursos 1 - 20 de 23

  1. Transthoracic echocardiography reference values in juvenile and adult 129/Sv mice

    Vinhas, Maurícia; Araújo, Ana Carolina; Ribeiro, Sónia; Rosário, Luís Brás; Belo, José António
    Background In the recent years, the use of Doppler-echocardiography has become a standard non-invasive technique in the analysis of cardiac malformations in genetically modified mice. Therefore, normal values have to be established for the most commonly used inbred strains in whose genetic background those mutations are generated. Here we provide reference values for transthoracic echocardiography measurements in juvenile (3 weeks) and adult (8 weeks) 129/Sv mice. Methods Echocardiographic measurements were performed using B-mode, M-mode and Doppler-mode in 15 juvenile (3 weeks) and 15 adult (8 weeks) mice, during isoflurane anesthesia. M-mode measurements variability of left ventricle (LV) was determined. Results Several echocardiographic measurements significantly...

  2. Shift happens: trailing edge contraction associated with recent warming trends threatens a distinct genetic lineage in the marine macroalga Fucus vesiculosus

    Nicastro, K. R.; Zardi, G. I.; Teixeira, Sara; Neiva, J.; Serrão, Ester; Pearson, G. A.
    Significant effects of recent global climate change have already been observed in a variety of ecosystems, with evidence for shifts in species ranges, but rarely have such consequences been related to the changes in the species genetic pool. The stretch of Atlantic coast between North Africa and North Iberia is ideal for studying the relationship between species distribution and climate change as it includes the distributional limits of a considerable number of both cold- and warm-water species. We compared temporal changes in distribution of the canopy-forming alga Fucus vesiculosus with historical sea surface temperature (SST) patterns to draw links between range...

  3. Genetic flow directionality and geographical segregation in a Cymodocea nodosa genetic diversity network

    Masucci, A. P.; Arnaud-Haond, S.; Eguíluz, V. M.; Hernández-García, E.; Serrão, Ester
    We analyse a large data set of genetic markers obtained from populations of Cymodocea nodosa, a marine plant occurring from the East Mediterranean to the Iberian-African coasts in the Atlantic Ocean. We fully develop and test a recently introduced methodology to infer the directionality of gene flow based on the concept of geographical segregation. Using the Jensen-Shannon divergence, we are able to extract a directed network of gene flow describing the evolutionary patterns of Cymodocea nodosa. In particular we recover the genetic segregation that the marine plant underwent during its evolution. The results are confirmed by natural evidence and are...

  4. Huntington's Disease and its therapeutic target genes: a global functional profile based on the HD Research Crossroads database

    Kalathur, Ravi K. R.; Hernández-Prieto, Miguel A; Futschik, Matthias
    Huntington’s disease (HD) is a fatal progressive neurodegenerative disorder caused by the expansion of the polyglutamine repeat region in the huntingtin gene. Although the disease is triggered by the mutation of a single gene, intensive research has linked numerous other genes to its pathogenesis. To obtain a systematic overview of these genes, which may serve as therapeutic targets, CHDI Foundation has recently established the HD Research Crossroads database. With currently over 800 cataloged genes, this web-based resource constitutes the most extensive curation of genes relevant to HD. It provides us with an unprecedented opportunity to survey molecular mechanisms involved in...

  5. Fine-scale genetic breaks driven by historical rangedynamics and ongoing density-barrier effects in theestuarine seaweed Fucus ceranoides L.

    Neiva, J.; Pearson, G. A.; Valero, M.; Serrão, Ester
    Factors promoting the emergence of sharp phylogeographic breaks include restricted dispersal, habitat discontinuity, physical barriers, disruptive selection, mating incompatibility, genetic surfing and secondary contact. Disentangling the role of each in any particular system can be difficult, especially when species are evenly distributed across transition zones and dispersal barriers are not evident. The estuarine seaweed Fucus ceranoides provides a good example of highly differentiated populations along its most persistent distributional range at the present rear edge of the species distribution, in NW Iberia. Intrinsic dispersal restrictions are obvious in this species, but have not prevented F. ceranoides from vastly expanding its...

  6. Functional characterization and evolution ofPTH/PTHrP receptors: insights from the chicken

    Pinheiro, Pedro L. C.; Cardoso, J. C. R.; Power, Deborah; Canario, Adelino V. M.
    The parathyroid hormone (PTH)-family consists of a group of structurally related factors that regulate calcium and bone homeostasis and are also involved in development of organs such as the heart, mammary gland and immune system. They interact with specific members of family 2 B1 G-protein coupled receptors (GPCRs), which have been characterised in teleosts and mammals. Two PTH/PTHrP receptors, PTH1R and PTH2R exist in mammals and in teleost fish a further receptor PTH3R has also been identified. Recently in chicken, PTH-family members involved in calcium transport were characterized and specific PTHRs are suggested to exist although they have not yet...

  7. Effects of genotype and dietary fish oil replacement with vegetable oil on the intestinal transcriptome and proteome of Atlantic salmon (Salmo salar)

    Silva, Tomé; Cordeiro, O.; Rodrigues, Pedro; Guy, Derrick R.; Bron, James E.; Taggart, John B.; Bell, J. Gordon; Tocher, Douglas R.
    Expansion of aquaculture requires alternative feeds and breeding strategies to reduce dependency on fish oil (FO) and better utilization of dietary vegetable oil (VO). Despite the central role of intestine in maintaining body homeostasis and health, its molecular response to replacement of dietary FO by VO has been little investigated. This study employed transcriptomic and proteomic analyses to study effects of dietary VO in two family groups of Atlantic salmon selected for flesh lipid content, 'Lean' or 'Fat'.ResultsMetabolism, particularly of lipid and energy, was the functional category most affected by diet. Important effects were also measured in ribosomal proteins and...

  8. A user-friendly software to easily count Anopheles egg batches

    Mollahosseini, Ali; Rossignol, Marie; Pennetier, Cédric; Cohuet, Anna; Anjos, António dos; Chandre, Fabrice; Shahbazkia, Hamid Reza
    Studies on malaria vector ecology and development/evaluation of vector control strategies often require measures of mosquito life history traits. Assessing the fecundity of malaria vectors can be carried out by counting eggs laid by Anopheles females. However, manually counting the eggs is time consuming, tedious, and error prone. Methods In this paper we present a newly developed software for high precision automatic egg counting. The software written in the Java programming language proposes a user-friendly interface and a complete online manual. It allows the inspection of results by the operator and includes proper tools for manual corrections. The user can in fact...

  9. Driving south: a multi-gene phylogeny of the brown algal family Fucaceae reveals relationships and recent drivers of a marine radiation

    Cánovas, Fernando G.; Mota, Catarina F.; Serrão, Ester; Pearson, G. A.
    Understanding the processes driving speciation in marine ecosystems remained a challenge until recently, due to the unclear nature of dispersal boundaries. However, recent evidence for marine adaptive radiations and ecological speciation, as well as previously undetected patterns of cryptic speciation is overturning this view. Here, we use multi-gene phylogenetics to infer the family-level evolutionary history of Fucaceae (intertidal brown algae of the northern Pacific and Atlantic) in order to investigate recent and unique patterns of radiative speciation in the genus Fucus in the Atlantic, in contrast with the mainly monospecific extant genera. Results We developed a set of markers from...

  10. Neogastropod phylogenetic relationships based on entire mitochondrial genomes

    Cunha, R. L.; Grande, Cristina; Zardoya, R.
    The Neogastropoda is a highly diversified group of predatory marine snails (Gastropoda: Caenogastropoda). Traditionally, its monophyly has been widely accepted based on several morphological synapomorphies mostly related with the digestive system. However, recent molecular phylogenetic studies challenged the monophyly of Neogastropoda due to the inclusion of representatives of other caenogastropod lineages (e.g. Littorinimorpha) within the group. Neogastropoda has been classified into up to six superfamilies including Buccinoidea, Muricoidea, Olivoidea, Pseudolivoidea, Conoidea, and Cancellarioidea. Phylogenetic relationships among neogastropod superfamilies remain unresolved. Results The complete mitochondrial (mt) genomes of seven Neogastropoda (Bolinus brandaris, Cancellaria cancellata, Conus borgesi, Cymbium olla, Fusiturris similis, Nassarius...

  11. Analysis of the asymmetrically expressed Ablim1 locus reveals existence of a lateral plate Nodal-independent left sided signal and an early, left-right independent role for nodal flow

    Stevens, Jonathan; Ermakov, Alexander; Braganca, José; Hilton, Helen; Underhill, Peter; Bhattacharya, Shoumo; Brown, Nigel A.; Norris, Dominic P.
    Abstract Background Vertebrates show clear asymmetry in left-right (L-R) patterning of their organs and associated vasculature. During mammalian development a cilia driven leftwards flow of liquid leads to the left-sided expression of Nodal, which in turn activates asymmetric expression of the transcription factor Pitx2. While Pitx2 asymmetry drives many aspects of asymmetric morphogenesis, it is clear from published data that additional asymmetrically expressed loci must exist. Results A L-R expression screen identified the cytoskeletally-associated gene, actin binding lim protein 1 (Ablim1), as asymmetrically expressed in both the node and left lateral plate mesoderm (LPM). LPM expression closely mirrors that of...

  12. Microplate-based high throughput screening procedure for the isolation of lipid-rich marine microalgae

    Pereira, Hugo; Barreira, Luísa Paula Viola Afonso; Mozes, Andre; Florindo, C.; Polo, Cristina; Duarte, Catarina V.; Custódio, Luísa Margarida Batista; Varela, J.
    Abstract We describe a new selection method based on BODIPY (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene) staining, fluorescence activated cell sorting (FACS) and microplate-based isolation of lipid-rich microalgae from an environmental sample. Our results show that direct sorting onto solid medium upon FACS can save about 3 weeks during the scale-up process as compared with the growth of the same cultures in liquid medium. This approach enabled us to isolate a biodiverse collection of several axenic and unialgal cultures of different phyla.

  13. Short RNA half-lives in the slow-growing marine cyanobacterium Prochlorococcus

    Steglich, Claudia; Lindell, Debbie; Futschik, Matthias; Rector, Trent; Steen, Robert; Chisholm, Sallie W
    Abstract Background RNA turnover plays an important role in the gene regulation of microorganisms and influences their speed of acclimation to environmental changes. We investigated whole-genome RNA stability of Prochlorococcus, a relatively slow-growing marine cyanobacterium doubling approximately once a day, which is extremely abundant in the oceans. Results Using a combination of microarrays, quantitative RT-PCR and a new fitting method for determining RNA decay rates, we found a median half-life of 2.4 minutes and a median decay rate of 2.6 minutes for expressed genes - twofold faster than that reported for any organism. The shortest transcript half-life (33 seconds) was...

  14. The European sea bass Dicentrarchus labrax genome puzzle: comparative BAC-mapping and low coverage shotgun sequencing

    Kuhl, H.; Beck, Alfred; Wozniak, Grzegorz; Canario, Adelino V. M.; Volckaert, F.; Reinhardt, Richard
    Abstract Background Food supply from the ocean is constrained by the shortage of domesticated and selected fish. Development of genomic models of economically important fishes should assist with the removal of this bottleneck. European sea bass Dicentrarchus labrax L. (Moronidae, Perciformes, Teleostei) is one of the most important fishes in European marine aquaculture; growing genomic resources put it on its way to serve as an economic model. Results End sequencing of a sea bass genomic BAC-library enabled the comparative mapping of the sea bass genome using the three-spined stickleback Gasterosteus aculeatus genome as a reference. BAC-end sequences (102,690) were aligned...

  15. Gill transcriptome response to changes in environmental calcium in the green spotted puffer fish

    Pinto, Patricia; Matsumura, H.; Thorne, Michael A. S.; Power, Deborah; Terauchi, Ryohei; Reinhardt, Richard; Canario, Adelino V. M.
    Abstract Background Calcium ion is tightly regulated in body fluids and for euryhaline fish, which are exposed to rapid changes in environmental [Ca2+], homeostasis is especially challenging. The gill is the main organ of active calcium uptake and therefore plays a crucial role in the maintenance of calcium ion homeostasis. To study the molecular basis of the short-term responses to changing calcium availability, the whole gill transcriptome obtained by Super Serial Analysis of Gene Expression (SuperSAGE) of the euryhaline teleost green spotted puffer fish, Tetraodon nigroviridis, exposed to water with altered [Ca2+] was analysed. Results Transfer of T. nigroviridis from...

  16. Boundary value problems for analytic functions in the class of Cauchy-type integrals with density in

    Kokilashvili, V.; Paatashvili, V.; Samko, S.
    We study the Riemann boundary value problem , for analytic functions in the class of analytic functions represented by the Cauchy-type integrals with density in the spaces with variable exponent. We consider both the case when the coefficient is piecewise continuous and it may be of a more general nature, admitting its oscillation. The explicit formulas for solutions in the variable exponent setting are given. The related singular integral equations in the same setting are also investigated. As an application there is derived some extension of the Szegö-Helson theorem to the case of variable exponents.

  17. Skin healing and scale regeneration in fed and unfed sea bream, Sparus auratus

    Vieira, Florbela A.; Gregório, Sílvia F.; Ferraresso, Serena; Thorne, Michael A. S.; Costa, Rita; Milan, Massimo; Bargelloni, Luca; Clark, M. S.; Canario, Adelino V. M.; Power, Deborah
    Abstract Background Fish scales are an important reservoir of calcium and phosphorus and together with the skin function as an integrated barrier against environmental changes and external aggressors. Histological studies have revealed that the skin and scales regenerate rapidly in fish when they are lost or damaged. In the present manuscript the histological and molecular changes underlying skin and scale regeneration in fed and fasted sea bream (Sparus auratus) were studied using a microarray 3 and 7 days after scale removal to provide a comprehensive molecular understanding of the early stages of these processes. Results Histological analysis of skin/scales revealed...

  18. Global analysis of gene expression in mineralizing fish vertebra-derived cell lines: new insights into anti-mineralogenic effect of vanadate

    Tiago, Daniel M.; Laizé, Vincent; Bargelloni, Luca; Ferraresso, Serena; Romualdi, Chiara; Cancela, Leonor
    Abstract Background Fish has been deemed suitable to study the complex mechanisms of vertebrate skeletogenesis and gilthead seabream (Sparus aurata), a marine teleost with acellular bone, has been successfully used in recent years to study the function and regulation of bone and cartilage related genes during development and in adult animals. Tools recently developed for gilthead seabream, e.g. mineralogenic cell lines and a 4 × 44K Agilent oligo-array, were used to identify molecular determinants of in vitro mineralization and genes involved in anti-mineralogenic action of vanadate. Results Global analysis of gene expression identified 4,223 and 4,147 genes differentially expressed (fold...

  19. Transcriptome sequencing and microarray development for the Manila clam, Ruditapes philippinarum: genomic tools for environmental monitoring

    Milan, Massimo; Coppe, Alessandro; Reinhardt, Richard; Cancela, Leonor; Leite, Ricardo B.; Saavedra, Carlos; Ciofi, Claudio; Chelazzi, Guido; Patarnello, T.; Bortoluzzi, Stefania; Bargelloni, Luca
    Abstract Background The Manila clam, Ruditapes philippinarum, is one of the major aquaculture species in the world and a potential sentinel organism for monitoring the status of marine ecosystems. However, genomic resources for R. philippinarum are still extremely limited. Global analysis of gene expression profiles is increasingly used to evaluate the biological effects of various environmental stressors on aquatic animals under either artificial conditions or in the wild. Here, we report on the development of a transcriptomic platform for global gene expression profiling in the Manila clam. Results A normalized cDNA library representing a mixture of adult tissues was sequenced...

  20. Insights into shell deposition in the Antarctic bivalve Laternula elliptica: gene discovery in the mantle transcriptome using 454 pyroseqeuencing

    Clark, M. S.; Thorne, Michael A. S.; Vieira, Florbela A.; Cardoso, J. C. R.; Power, Deborah; Peck, Lloyd S.
    Abstract Background The Antarctic clam, Laternula elliptica, is an infaunal stenothermal bivalve mollusc with a circumpolar distribution. It plays a significant role in bentho-pelagic coupling and hence has been proposed as a sentinel species for climate change monitoring. Previous studies have shown that this mollusc displays a high level of plasticity with regard to shell deposition and damage repair against a background of genetic homogeneity. The Southern Ocean has amongst the lowest present-day CaCO3 saturation rate of any ocean region, and is predicted to be among the first to become undersaturated under current ocean acidification scenarios. Hence, this species presents...

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