1,126 research outputs found

    EXMOTIF: efficient structured motif extraction

    Get PDF
    BACKGROUND: Extracting motifs from sequences is a mainstay of bioinformatics. We look at the problem of mining structured motifs, which allow variable length gaps between simple motif components. We propose an efficient algorithm, called EXMOTIF, that given some sequence(s), and a structured motif template, extracts all frequent structured motifs that have quorum q. Potential applications of our method include the extraction of single/composite regulatory binding sites in DNA sequences. RESULTS: EXMOTIF is efficient in terms of both time and space and is shown empirically to outperform RISO, a state-of-the-art algorithm. It is also successful in finding potential single/composite transcription factor binding sites. CONCLUSION: EXMOTIF is a useful and efficient tool in discovering structured motifs, especially in DNA sequences. The algorithm is available as open-source at:

    GRISOTTO: A greedy approach to improve combinatorial algorithms for motif discovery with prior knowledge

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Position-specific priors (PSP) have been used with success to boost EM and Gibbs sampler-based motif discovery algorithms. PSP information has been computed from different sources, including orthologous conservation, DNA duplex stability, and nucleosome positioning. The use of prior information has not yet been used in the context of combinatorial algorithms. Moreover, priors have been used only independently, and the gain of combining priors from different sources has not yet been studied.</p> <p>Results</p> <p>We extend RISOTTO, a combinatorial algorithm for motif discovery, by post-processing its output with a greedy procedure that uses prior information. PSP's from different sources are combined into a scoring criterion that guides the greedy search procedure. The resulting method, called GRISOTTO, was evaluated over 156 yeast TF ChIP-chip sequence-sets commonly used to benchmark prior-based motif discovery algorithms. Results show that GRISOTTO is at least as accurate as other twelve state-of-the-art approaches for the same task, even without combining priors. Furthermore, by considering combined priors, GRISOTTO is considerably more accurate than the state-of-the-art approaches for the same task. We also show that PSP's improve GRISOTTO ability to retrieve motifs from mouse ChiP-seq data, indicating that the proposed algorithm can be applied to data from a different technology and for a higher eukaryote.</p> <p>Conclusions</p> <p>The conclusions of this work are twofold. First, post-processing the output of combinatorial algorithms by incorporating prior information leads to a very efficient and effective motif discovery method. Second, combining priors from different sources is even more beneficial than considering them separately.</p

    Immunophenotypic features of tumor infiltrating lymphocytes from mammary carcinomas in female dogs associated with prognostic factors and survival rates

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The immune system plays an important role in the multifactorial biologic system during the development of neoplasias. However, the involvement of the inflammatory response in the promotion/control of malignant cells is still controversial, and the cell subsets and the mechanisms involved are poorly investigated. The goal of this study was to characterize the clinical-pathological status and the immunophenotyping profile of tumor infiltrating lymphocytes and their association with the animal survival rates in canine mammary carcinomas.</p> <p>Methods</p> <p>Fifty-one animals with mammary carcinomas, classified as carcinomas in mixed tumors-MC-BMT = 31 and carcinomas-MC = 20 were submitted to systematic clinical-pathological analysis (tumor size; presence of lymph node and pulmonary metastasis; clinical stage; histological grade; inflammatory distribution and intensity as well as the lymphocytic infiltrate intensity) and survival rates. Twenty-four animals (MC-BMT = 16 and MC = 8) were elected to the immunophenotypic study performed by flow cytometry.</p> <p>Results</p> <p>Data analysis demonstrated that clinical stage II-IV and histological grade was I more frequent in MC-BMT as compared to MC. Univariate analysis demonstrated that the intensity of inflammation (moderate/intense) and the proportion of CD4<sup>+ </sup>(≥ 66.7%) or CD8<sup>+ </sup>T-cells (<33.3%) were not associated with worse survival rate. Multivariate analysis demonstrated that only lymphocytic infiltrate intensity ≥ 600 (<it>P </it>= 0.02) remained as independent prognostic factor. Despite the clinical manifestation, the lymphocytes represented the predominant cell type in the tumor infiltrate. The percentage of T-cells was higher in animals with MC-BMT without metastasis, while the percentage of B-lymphocytes was greater in animals with metastasized MC-BMT (<it>P </it>< 0.05). The relative percentage of CD4<sup>+ </sup>T-cells was significantly greater in metastasized tumors (both MC-BMT and MC), (<it>P </it>< 0.05) while the proportion of CD8<sup>+ </sup>T-cells was higher in MC-BMT without metastasis. Consequently, the CD4<sup>+</sup>/CD8<sup>+ </sup>ratio was significantly increased in both groups with metastasis. Regardless of the tumor type, the animals with high proportions of CD4<sup>+ </sup>and low CD8<sup>+ </sup>T-cells had decreased survival rates.</p> <p>Conclusion</p> <p>The intensity of lymphocytic infiltrate and probably the relative abundance of the CD4<sup>+ </sup>and CD8<sup>+ </sup>T-lymphocytes may represent important survival prognostic biomarkers for canine mammary carcinomas.</p

    A cross-national study on the antecedents of work–life balance from the fit and balance perspective

    Get PDF
    Drawing on the perceived work–family fit and balance perspective, this study investigates demands and resources as antecedents of work–life balance (WLB) across four countries (New Zealand, France, Italy and Spain), so as to provide empirical cross-national evidence. Using structural equation modelling analysis on a sample of 870 full time employees, we found that work demands, hours worked and family demands were negatively related to WLB, while job autonomy and supervisor support were positively related to WLB. We also found evidence that resources (job autonomy and supervisor support) moderated the relationships between demands and work–life balance, with high resources consistently buffering any detrimental influence of demands on WLB. Furthermore, our study identified additional predictors of WLB that were unique to some national contexts. For example, in France and Italy, overtime hours worked were negatively associated with WLB, while parental status was positively associated with WLB. Overall, the implications for theory and practice are discussed.Peer ReviewedPostprint (author's final draft

    Como os trabalhadores de um Centro Obstétrico justificam a utilização de práticas prejudiciais ao parto normal

    Get PDF
    Este estudo busca entender as justificativas dos trabalhadores de um Centro Obstétrico do Sul do Brasil para a utilização de práticas do parto normal consideradas prejudiciais pela Organização Mundial da Saúde. A pesquisa é do tipo exploratória, desenvolvida em julho de 2009, por meio de entrevista com 23 trabalhadores. Na análise, houve a conformação de três núcleos temáticos: Ações e condutas na dependência do trabalhador de saúde; Práticas rotineiras como facilitadoras do trabalho e Restrição da participação da parturiente no processo decisório. Algumas justificativas para o emprego das práticas: perpetuação de modelos inadequados, facilitação para a assistência no momento do parto e autoritarismo que alguns trabalhadores exercem sobre a parturiente por acreditarem serem detentores do conhecimento

    The action of a multidisciplinary team in the nutritional care of critically ill patients

    Get PDF
    Hospitalized patients may have special nutrient requirements imposed by a combination of malnutrition and enhanced utilization of nutrients resulting from the disease process. Nutritional support, mainly during critical stages of disease, should be provided safely and effectively. Several studies have evaluated the paper of a multidisciplinary team in the administration of a nutritional therapy. Individually, the majority of these studies are underpowered to evaluate an effect on the quality of nutritional care. With the objective to identify problems inherent to the supply of nutritional support to hospitalized patients and verify the impact of the actions of a multidisciplinary team on the quality of these procedures, we analysed articles that have been published between 1980 and 2004 about the role of the action of multidisciplinary teams in the care and nutritional outcome of hospitalized patients, especially those undergoing intensive care. The terms used for the search were: multidisciplinary team, nutritional support, parenteral nutrition, enteral feeding, critically ill, intensive care unit, critically ill child. Of 130 studies, intially identified, just 24 were selected, of which 14 compared the standard of nutritional therapy with and without the presence of a multidisciplinary team. The inadequate supply of nutrients, infection and metabolic complications and the excessive use of parenteral nutrition were the main problems detected in the supply of nutritional support to hospitalized patients. In the comparative studies, the presence of the multidisciplinary team improved the pattern of nutritional support, and reduced the incidence of complications and the costs.Pacientes hospitalizados podem ter necessidades nutricionais especiais em função da desnutrição e dos desequilíbrios metabólicos impostos pelas doenças. A terapia nutricional, principalmente nos estágios críticos das enfermidades, deve ser administrada de modo seguro e eficaz. Vários estudos têm avaliado o papel da equipe multidisciplinar na administração da terapia nutricional. Com o objetivo de identificar os problemas inerentes à administração da terapia nutricional em pacientes hospitalizados e verificar o impacto da atuação de uma equipe multidisciplinar na qualidade dos procedimentos, foi realizada uma revisão que analisou artigos publicados entre 1980 e 2004 sobre o papel da atuação de equipes multidisciplinares no cuidado e na evolução nutricional de pacientes hospitalizados, principalmente os que se encontravam sob cuidados intensivos. Os termos utilizados na pesquisa foram: multidisciplinary team, nutritional support, parente-ral nutrition, enteral feeding, critically ill, intensive care unit,critically ill child. Dos 130 estudos inicialmente identificados, foram selecionados 24, dos quais 14 compararam o padrão de terapia nutricional com e sem a presença da equipe multidisciplinar. Os principais problemas detectados na administração de terapia nutricional em pacientes hospitalizados foram a oferta inadequada de nutrientes, as complicações infecciosas e metabólicas e o uso excessivo de nutrição parenteral. Nos estudos comparativos, a presença da equipe multidisciplinar melhorou o padrão de oferta nutricional, reduziu a incidência de complicações e os custos.Universidade Federal de São Paulo (UNIFESP) Departamento de PediatriaHospital São Paulo Unidade de Cuidados Intensivos PediátricosHospital São Paulo Equipe Multidisciplinar de Terapia NutricionalUNIFESP, Depto. de PediatriaHospital São Paulo Unidade de Cuidados Intensivos PediátricosHospital São Paulo Equipe Multidisciplinar de Terapia NutricionalSciEL
    • …
    corecore