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Wnt signaling is essential during animal development and also plays important roles in pathological conditions. Two mayor pathways have been described: the beta-catenin-dependent canonical (or classical) pathway and the beta-catenin-independent non-canonical Wnt pathway. Recent binding studies suggest links between the small PDZ protein TIP-1 (Tax-1 interacting protein) to components of both Wnt pathways. We have cloned and characterized the zebrafish tip-1 gene. Whole mount in situ hybridization and semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) indicated that zebrafish tip-1 is present as a maternal RNA and is ubiquitously expressed during early development. After 24 h of development, tip-1 expression was high in the central nervous system (CNS) whereas only weak expression was detected in the caudal regions of the zebrafish embryo. Tip-1 knockdown using antisense morpholino oligonucleotides, as well as ectopic tip-1 expression, led to elongation defects in zebrafish embryos and larvae. Both knockdown and overexpression of tip-1 resulted in a widened goosecoid (gsc) expression domain in shield stage embryos, led to an abbreviated prechordal plate, and to reduced convergent extension movements during gastrulation. We constructed a green fluorescence protein (GFP)/TIP-1 fusion protein which, when expressed in cultured fibroblasts (ZF4-cells), induced filopodia growth. Our observations indicate a role for TIP-1 in gastrulation movements and in filopodia growth induction.

A teoria dos jogos visa determinar estrategias otimas para o jogador. Estrategia e uma regra, um plano de acoes determinados para obter um objetivo especifico, ela visa maximizar um ou varios resultados que possibilitem uma situacao otima para o jogador em um cenario qualquer de um jogo. Um jogo e uma situacao na qual dois ou mais participantes (ou jogadores) competem em busca de certos objetivos, conflitantes [1]. A criacao de modelos e um fator importante para o apoio da tomada de decisao, onde e desejado a maximizacao da utilidade do decisor. Um sistema de apoio a tomada de decisao tem seu uso indicado nesses casos. [2]. Os problemas complexos de tomada de decisao sao comuns em uma infinidade de areas [3], como, por exemplo, os jogos, administracao de empresas, entre outros. Esses problemas ocorrem quando os criterios de resolucao do problema sao, no minimo, dois que conflitam entre si. O presente trabalho propoe a determinacao de uma boa estrategia de jogo, que indique ao jogador qual a melhor opcao para atacar, considerando varios inimigos situados em distâncias distintas em relacao ao jogador em uma situacao de certeza. De acordo com [2], uma situacao de certeza ocorre quando temos informacoes completas e conhecemos a priori o resultado associado a cada acao. O jogo proposto consiste em um unico jogador competindo em um ambiente virtual, contra varios inimigos que tentam se aproximar da regiao que o jogador se encontra e, ao entrar nessa area de influencia, acaba por efetuar uma diminuicao no parâmetro vida do jogador. Em uma situacao hipotetica de jogo, conforme representado na figura 1, consideramos 3 variaveis de decisao que sao: vida que varia de 0 a 100 (quantidade de vida do jogador), Dist (representa a distância entre jogador e inimigo) e I que varia de 0 a 100 e representa o grau de intimidacao do inimigo. J I2 I1 I4 I3 d2 d1 d3 d4 Figura 1:Cenario de jogo Temos que J e o jogador, I1, I2, I3 e I4 sao os inimigos e d1, d2, d3 e d4 sao as distâncias entre o jogador e cada inimigo. [...]

Mammalian CYPHER (Oracle, KIA0613), a member of the PDZ-LIM family of proteins (Enigma/LMP-1, ENH, ZASP/Cypher, RIL, ALP, and CLP-36), has been associated with cardiac and muscular myopathies. Targeted deletion of Cypher in mice is neonatal lethal possibly caused by myopathies. To further investigate the role of cypher in development, we have cloned the zebrafish orthologue. We present here the gene, domain structure, and expression pattern of zebrafish cypher during development. Cypher was not present as a maternal mRNA and was absent during early development. Cypher mRNA was first detected at the 3-somite stage in adaxial somites, and as somites matured, cypher expression gradually enveloped the whole somite. Later, cypher expression was also found in the heart, in head and jaw musculature, and in the brain. We further identified 13 alternative spliced forms of cypher from zebrafish heart and skeletal muscle tissue, among them a very short form containing the PDZ domain but lacking the ZM (ZASP-like) motif and the LIM domains. Targeted gene knock-down experiments using cypher antisense morpholinos led to severe defects, including truncation of the embryo, deformation of somites, dilatation of the pericardium, and thinning of the ventricular wall. The phenotype could be rescued by a cypher form, which contains the PDZ domain and the ZM motif, but lacks all three LIM domains. These findings indicate that a PDZ domain protein is important for normal somite formation and in normal heart development. Treatment of zebrafish embryos with cyclopamine, which disrupts hedgehog signaling, abolished cypher expression in 9 somite and 15-somite stage embryos. Taken together, our data suggest that cypher may play a role downstream of sonic hedgehog, in a late stage of somite development, when slow muscle fibers differentiate and migrate from the adaxial cells.

Low oxygen levels (hypoxia) play a role in clinical conditions such as stroke, chronic ischemia, and cancer. To better understand these diseases, it is crucial to study the responses of vertebrates to hypoxia. Among vertebrates, some teleosts have developed the ability to adapt to extremely low oxygen levels. We have studied long-term adaptive responses to hypoxia in adult zebrafish. We used zebrafish that survived severe hypoxic conditions for 3 wk and showed adaptive behavioral and phenotypic changes. We used cDNA microarrays to investigate hypoxia-induced changes in expression of 15,532 genes in the respiratory organs (the gills). We have identified 367 differentially expressed genes of which 117 showed hypoxia-induced and 250 hypoxia-reduced expressions. Metabolic depression was indicated by repression of genes in the TCA cycle in the electron transport chain and of genes involved in protein biosynthesis. We observed enhanced expression of the monocarboxylate transporter and of the oxygen transporter myoglobin. The hypoxia-induced group further included the genes for Niemann-Pick C disease and for Wolman disease [lysosomal acid lipase (LAL)]. Both diseases lead to a similar intra- and extracellular accumulation of cholesterol and glycolipids. The Niemann-Pick C protein binds to cholesterol from internal lysosomal membranes and is involved in cholesterol trafficking. LAL is responsible for lysosomal cholesterol degradation. Our data suggest a novel adaptive mechanism to hypoxia, the induction of genes for lysosomal lipid trafficking and degradation. Studying physiological responses to hypoxia in species tolerant for extremely low oxygen levels can help identify novel regulatory genes, which may have important clinical implications.

82p DHA/NEC 2014 12 a 16 de maio

Misuse Made Plain: Evaluating Concerns About Neuroscience in National Security Kelly Lowenberg a , Brenda M. Simon a , Amy Burns b , Libby Greismann c , Jennifer M. Halbleib b , Govind Persad b , David L.M. Preston c , Harker Rhodes b & Emily R. Murphy d a Stanford Law School Center for Law and the Biosciences , b Stanford Law School , c Stanford University , d Stanford Law School and Director of SIGNAL , Published online: 16 Apr 2010.

Coastal and estuarine nowcast-forecast systems started being developed in the 1990’s to provide coastal managers with short-term oceanographic predictions (e.g., waves, tides). Over the years, they evolved in both scope and functionality. Forecasts now simulate more physical processes, and chemical and biological processes are being added. Additionally, better functionalities are being developed to convey data and model results to the user. This paper describes recent advances in the development of a nowcast-forecast system, RDFS-PT, in operation for the Portuguese coast. This system, which provides wave and circulation forecasts, for the Portuguese shelf and two estuaries, and automated data-model comparisons, is now being extended for baroclinic circulation and fecal contamination simulation in the Tagus estuary. Moreover, its interface is being revamped to take advantage of webGIS technologies and to include real-time water quality data from monitoring networks under deployment in the Tagus estuary DHA/NEC 2013 4 a 7 de junho

O alerta precoce de emergências e catástrofes (cheias, eventos graves de poluição, tsunamis) pode contribuir para a protecção do património e da vida humana em zonas costeiras e ribeirinhas. A previsão atempada destes eventos é essencial para a gestão do risco em comunidades vulneráveis, contribuindo para suportar decisões sobre a evacuação da população, a alocação de recursos para proteger valores humanos e ambientais e a gestão eficiente do pessoal de apoio na resposta à emergência. Os sistemas de previsão em tempo real são ferramentas fundamentais para a gestão do risco nestas zonas, produzindo previsões a escalas de tempo curtas, através da integração de modelos e dados de campo. Estes sistemas podem ainda ser integrados com sistemas de alerta, para apoio às entidades gestoras. A presente comunicação enquadra-se no projecto PREPARED Enabling Change (7PQ). Este projecto inclui um conjunto de casos de demonstração, nos quais está incluída a cidade de Lisboa. Para esta cidade, será desenvolvido um sistema piloto de alerta para riscos de saúde pública associados a contaminação fecal das águas de recreio, aplicado à frente ribeirinha do estuário do Tejo. Este sistema está a ser desenvolvido com base na adaptação do sistema de previsão em tempo real do LNEC (RDFS-PT), actualmente em 10º Simpósio de Hidráulica e de Recursos Hídricos dos Países de Língua Portuguesa Porto de Galinhas/PE, Setembro de 2011 ______________________________________________________________________________________________ vs.01 1 operação para previsão da circulação em vários estuários e da agitação marítima na costa Portuguesa (http://ariel.lnec.pt), para a simulação conjunta do escoamento e transporte na rede de colectores e no meio receptor (estuário do Tejo), suportada por uma rede de sensores em tempo real e por estudos laboratoriais. Esta comunicação apresenta o sistema actual de previsão da circulação em tempo real e a sua validação, por comparação com dados históricos e dados em tempo real, assim como a metodologia de abordagem para a criação do sistema de alerta. É ainda apresentado o modelo 3D acoplado da hidrodinâmica – contaminação fecal de Rodrigues et al. (2011), que constituirá a base de modelação para o sistema de alerta. 14 DHA/NTI

Wnt signaling is essential during animal development and also plays important roles in pathological conditions. Two mayor pathways have been described: the beta-catenin-dependent canonical (or classical) pathway and the beta-catenin-independent non-canonical Wnt pathway. Recent binding studies suggest links between the small PDZ protein TIP-1 (Tax-1 interacting protein) to components of both Wnt pathways. We have cloned and characterized the zebrafish tip-1 gene. Whole mount in situ hybridization and semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) indicated that zebrafish tip-1 is present as a maternal RNA and is ubiquitously expressed during early development. After 24 h of development, tip-1 expression was high in the central nervous system (CNS) whereas only weak expression was detected in the caudal regions of the zebrafish embryo. Tip-1 knockdown using antisense morpholino oligonucleotides, as well as ectopic tip-1 expression, led to elongation defects in zebrafish embryos and larvae. Both knockdown and overexpression of tip-1 resulted in a widened goosecoid (gsc) expression domain in shield stage embryos, led to an abbreviated prechordal plate, and to reduced convergent extension movements during gastrulation. We constructed a green fluorescence protein (GFP)/TIP-1 fusion protein which, when expressed in cultured fibroblasts (ZF4-cells), induced filopodia growth. Our observations indicate a role for TIP-1 in gastrulation movements and in filopodia growth induction.

This study aims at understanding the fecal contamination behavior in a small coastal stream (Aljezur, Portugal), which has significant economic and ecological values. Like in most small coastal systems, circulation and water renewal in the Aljezur stream exhibit a strong variability due to their dependence on tides, waves, intermittent river flows, and a highly variable morphology. Hence, the problem was approached through a combination of field surveys and the development and application of a hard-coupled three-dimensional hydrodynamic and fecal contamination model. Salinity and temperature results have shown that mixing and transport in the stream are very sensitive to the river flow and wind forcing. The model is able to represent the main patterns and trends observed in Escherichia coli and fecal enterococcus concentrations along the stream, for different environmental and contamination conditions, suggesting die-off rates on the order of 0.50–0.55 day−1. Die-off rate and the representation of the sediment-associated processes were identified as the major remaining sources of uncertainty in the model. Results show that, owing to the processes that occur along the stream, fecal bacteria reach the beaches water in numbers that comply with the European Bathing Waters Directive, even during the summer periods when the upstream concentrations are larger. In particular, results suggest a direct relation between the tidal propagation upstream and the reduction of the fecal bacteria concentrations along the stream that can be relevant for the development of a strategy for the management of the system’s water safety. 841–856 pp 61 DHA/NEC Ocean Dynamics