2,728 research outputs found
Fibroblast growth factor receptor 4 single nucleotide polymorphism Gly388Arg in head and neck carcinomas
BACKGROUND Head and neck squamous cell carcinoma (HNSCC) is considered to be a progressive disease resulting from alterations in multiple genes regulating cell proliferation and differentiation like receptor tyrosine kinases (RTKs) and members of the fibroblast growth factor receptors (FGFR)-family. Single-nucleotide polymorphism (SNP) Arg388 of the FGFR4 is associated with a reduced overall survival in patients with cancers of various types. We speculate that FGFR4 expression and SNP is associated with worse survival in patients with HSNCC. AIM To investigate the potential clinical significance of FGFR4 Arg388 in the context of tumors arising in HNSCC, a comprehensive analysis of FGFR4 receptor expression and genotype in tumor tissues and correlated results with patients' clinical data in a large cohort of patients with HNSCC was conducted. METHODS Surgical specimens from 284 patients with HNSCC were retrieved from the Institute of Pathology at the Ludwig-Maximilian-University in Germany. Specimens were analyzed using immunohistochemistry and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The expression of FGFR4 was analyzed in 284 surgical specimens of HNSCC using immunohistochemstry. FGFR4 polymorphism was detected by PCR-RFLP. Patients' clinical data with a minimum follow-up of 5 syears were statistically evaluated with a special emphasis on survival analysis employing Kaplan-Meier estimator and Cox regression analysis. RESULTS Concerning the invasive tumor areas the intensity of the FGFR4 expression was evaluated in a four-grade system: no expression, low expression, intermediate and high expression. FGFR4 expression was scored as "high" (+++) in 74 (26%), "intermediate" (++) in 103 (36.3%), and "low" (+) in 107 (36.7%) cases. Analyzing the FGFR4 mutation it was found in 96 tumors (33.8%), 84 of them (29.6%) having a heterozygous and 12 (4.2%) homozygous mutated Arg388 allele. The overall frequency concerning the mutant alleles demonstrated 65% vs 34% mutated alleles in general. FGFR4 Arg388 was significantly associated with advanced tumor stage (P < 0.004), local metastasis (P < 0.0001) and reduced disease-free survival (P < 0.01). Furthermore, increased expression of FGFR4 correlated significantly with worse overall survival (P < 0.003). CONCLUSION In conclusion, the FGFR4 Arg388 genotype and protein expression of FGFR4 impacts tumor progression in patients with HNSCC and may present a useful target within a multimodal therapeutic intervention
Searching for Communities in Bipartite Networks
Bipartite networks are a useful tool for representing and investigating
interaction networks. We consider methods for identifying communities in
bipartite networks. Intuitive notions of network community groups are made
explicit using Newman's modularity measure. A specialized version of the
modularity, adapted to be appropriate for bipartite networks, is presented; a
corresponding algorithm is described for identifying community groups through
maximizing this measure. The algorithm is applied to networks derived from the
EU Framework Programs on Research and Technological Development. Community
groups identified are compared using information-theoretic methods.Comment: 12 pages, 4 figures, to appear in "Proceedings of the 5th Jagna
International Workshop: Stochastic and Quantum Dynamics of Biomolecular
Systems," C. C. Bernido and M. V. Carpio-Bernido, editors. A version with
full-quality figures and larger file size is available at
http://ccm.uma.pt/publications/Barber-Faria-Streit-Strogan-2008.pd
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Characterizing Cancer Subtypes Using Dual Analysis in Caleydo StratomeX
Dual analysis uses statistics to describe both the dimensions and rows of a high-dimensional dataset. Researchers have integrated it into StratomeX, a Caleydo view for cancer subtype analysis. In addition, significant-difference plots show the elements of a candidate subtype that differ significantly from other subtypes, thus letting analysts characterize subtypes. Analysts can also investigate how data samples relate to their assigned subtype and other groups. This approach lets them create well-defined subtypes based on statistical properties. Three case studies demonstrate the approach's utility, showing how it reproduced findings from a published subtype characterization
NMDA receptor content of synapses in stratum radiatum of the hippocampal CA1 area
Glutamate receptors activated by NMDA (NMDARs) or AMPA (AMPARs) are clustered on dendritic spines of pyramidal cells. Both the AMPAR-mediated postsynaptic responses and the synaptic AMPAR immunoreactivity show a large intersynapse variability. Postsynaptic responses mediated by NMDARs show less variability. To assess the variability in NMDAR content and the extent of their coexistence with AMPARs in Schaffer collateral-commissural synapses of adult rat CA1 pyramidal cells, electron microscopic immunogold localization of receptors has been used. Immunoreactivity of NMDARs was detected in virtually all synapses on spines, but AMPARs were undetectable, on average, in 12% of synapses. A proportion of synapses had a very high AMPAR content relative to the mean content, resulting in a distribution more skewed toward larger values than that of NMDARs. The variability of synaptic NMDAR content [coefficient of variation (CV), 0.64-0.70] was much lower than that of the AMPAR content (CV, 1.17-1.45). Unlike the AMPAR content, the NMDAR content showed only a weak correlation with synapse size. As reported previously for AMPARs, the immunoreactivity of NMDARs was also associated with the spine apparatus within spines. The results demonstrate that the majority of the synapses made by CA3 pyramidal cells onto spines of CA1 pyramids express both NMDARs and AMPARs, but with variable ratios. A less-variable NMDAR content is accompanied by a wide variability of AMPAR content, indicating that the regulation of expression of the two receptors is not closely linked. These findings support reports that fast excitatory transmission at some of these synapses is mediated by activation mainly of NMDARs
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Guide Me in Analysis: A Framework for Guidance Designers
Guidance is an emerging topic in the field of visual analytics. Guidance can support users in pursuing their analytical goals more efficiently and help in making the analysis successful. However, it is not clear how guidance approaches should be designed and what specific factors should be considered for effective support. In this paper, we approach this problem from the perspective of guidance designers. We present a framework comprising requirements and a set of specific phases designers should go through when designing guidance for visual analytics. We relate this process with a set of quality criteria we aim to support with our framework, that are necessary for obtaining a suitable and effective guidance solution. To demonstrate the practical usability of our methodology, we apply our framework to the design of guidance in three analysis scenarios and a design walk-through session. Moreover, we list the emerging challenges and report how the framework can be used to design guidance solutions that mitigate these issues
An alternative heavy Higgs mass limit
After commenting on the present value of the Higgs particle mass from
radiative corrections, we explore the phenomenological implications of an
alternative, non-perturbative renormalization of the scalar sector where the
mass of the Higgs particle does not represent a measure of observable
interactions at the Higgs mass scale. In this approach the Higgs particle could
be very heavy, even heavier than 1 TeV, and remain nevertheless a relatively
narrow resonance.Comment: 17 pages. Version accepted for publication in Journal of Physics
Competitiveness and communication for effective inoculation byRhizobium, Bradyrhizobium and vesicular-arbuscular mycorrhiza fungi
After a short summary on the ecology and rhizosphere biology of symbiotic bacteria and vesicular-arbuscular (VA) mycorrhiza fungi and their application as microbial inocula, results on competitiveness and communication are summarized. Stress factors such as high temperature, low soil pH, aluminium concentrations and phytoalexins produced by the host plants were studied withRhizobium leguminosarum bv.phaseoli andRhizobium tropici onPhaseolus beans. Quantitative data for competitiveness were obtained by usinggus + (glucoronidase) labelled strains, which produce blue-coloured nodules. ForPhaseolus-nodulating rhizobia, a group specific DNA probe was also developed, which did not hybridize with more than 20 other common soil and rhizosphere bacteria. Results from several laboratories contributing to knowledge of signal exchange and communication in theRhizobium/Bradyrhizobium legume system are summarized in a new scheme, including also defense reactions at the early stages of legume nodule initiation. Stimulating effects of flavonoids on germination and growth of VA mycorrhiza fungi were also found. A constitutive antifungal compound in pea roots, -isoxazolinonyl-alanine, was characterized
Recomendações técnicas para a reprodução do tambaqui.
Das espécies nativas brasileiras, o tambaqui (Colossoma macropomum) é a mais produzida em cativeiro. Quase a totalidade da produção desse animal puro ocorre nos estados da região Norte do Brasil, com destaque para Rondônia. No Mato Grosso, existe grande produção do híbrido tambacu (tambaqui x pacu-caranha, Piaractus mesopotamicus). Isso se deve à popularidade do pacu-caranha na bacia do rio Paraguai e do repasse de tecnologia, no início dos anos 1980, do Centro Nacional de Pesquisa e Conservação de Peixes Continentais (Cepta), que recomendava a produção do híbrido com o objetivo de explorar o potencial de crescimento do tambaqui associado à resistência do pacu a temperaturas amenas. Atualmente, outro híbrido bastante produzido é o tambatinga, cruzamento de duas espécies amazônicas (tambaqui x pirapitinga, Piaractus brachypomus) com características produtivas parecidas com as do tambacu, mas com destaque para a cor prateada e o opérculo avermelhado, os quais chamam a atenção do consumidor. Desse modo, este manual vai tratar exclusivamente da tecnologia aplicada à reprodução do tambaqui, desenvolvida pela UFRGS, UEM e UFMT com apoio da Embrapa, por meio do Programa de Melhoramento Genético de Organismos Aquáticos, no âmbito do projeto AQUABRASIL.bitstream/item/83462/1/Doc-212-RecomendacoesTecnicasReproducaoTambaqui.pd
Meeting report : 1st international functional metagenomics workshop May 7–8, 2012, St. Jacobs, Ontario, Canada
This report summarizes the events of the 1st International Functional Metagenomics Workshop. The workshop was held on May 7 and 8 in St. Jacobs, Ontario, Canada and was focused on building a core international functional metagenomics community, exploring strategic research areas, and identifying opportunities for future collaboration and funding. The workshop was initiated by researchers at the University of Waterloo with support from the Ontario Genomics Institute (OGI), Natural Sciences and Engineering Research Council of Canada (NSERC) and the University of Waterloo
Feynman integrals for non-smooth and rapidly growing potentials
The Feynman integral for the Schrödinger propagator is constructed as a generalized
function of white noise, for a linear space of potentials spanned by finite
signed measures of bounded support and Laplace transforms of such measures,
i.e., locally singular as well as rapidly growing at infinity. Remarkably, all these
propagators admit a perturbation expansion
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