Cancer Biomarker Discovery: The Entropic Hallmark

Background: It is a commonly accepted belief that cancer cells modify their transcriptional state during the progression of the disease. We propose that the progression of cancer cells towards malignant phenotypes can be efficiently tracked using high-throughput technologies that follow the gradual changes observed in the gene expression profiles by employing Shannon's mathematical theory of communication. Methods based on Information Theory can then quantify the divergence of cancer cells' transcriptional profiles from those of normally appearing cells of the originating tissues. The relevance of the proposed methods can be evaluated using microarray datasets available in the public domain but the method is in principle applicable to other high-throughput methods. Methodology/Principal Findings: Using melanoma and prostate cancer datasets we illustrate how it is possible to employ Shannon Entropy and the Jensen-Shannon divergence to trace the transcriptional changes progression of the disease. We establish how the variations of these two measures correlate with established biomarkers of cancer progression. The Information Theory measures allow us to identify novel biomarkers for both progressive and relatively more sudden transcriptional changes leading to malignant phenotypes. At the same time, the methodology was able to validate a large number of genes and processes that seem to be implicated in the progression of melanoma and prostate cancer. Conclusions/Significance: We thus present a quantitative guiding rule, a new unifying hallmark of cancer: the cancer cell's transcriptome changes lead to measurable observed transitions of Normalized Shannon Entropy values (as measured by high-throughput technologies). At the same time, tumor cells increment their divergence from the normal tissue profile increasing their disorder via creation of states that we might not directly measure. This unifying hallmark allows, via the the Jensen-Shannon divergence, to identify the arrow of time of the processes from the gene expression profiles, and helps to map the phenotypical and molecular hallmarks of specific cancer subtypes. The deep mathematical basis of the approach allows us to suggest that this principle is, hopefully, of general applicability for other diseases

Situação de crianças e adolescentes brasileiros em relação à saúde mental e à violência The situation of Brazilian children and adolescents with regard to mental health and violence

Este artigo reflete sobre as violências cometidas contra crianças e adolescentes brasileiros e suas repercussões sobre a saúde mental, propondo um debate sobre a necessidade das políticas públicas de saúde priorizarem temáticas de tamanha relevância. No país, tem-se verificado que a discussão dos temas "violência e problemas de saúde mental em crianças e adolescentes" vem ocorrendo de forma fragmentada e pouco consistente. Este trabalho traz uma seleção não sistemática de estudos epidemiológicos desenvolvidos em escolas e comunidades brasileiras sobre o assunto. A ampla variedade e a prevalência da violência familiar e comunitária e dos problemas de saúde mental são apontadas, ressaltando-se as diferenças metodológicas dos métodos de aferição e a concentração de estudos nas regiões sul e sudeste do país. A ainda escassa rede de atendimento para os problemas aqui tratados é sinalizada, assim como a falta de preocupação com a prevenção do transtorno mental e com a promoção da saúde mental.<br>This article reflects about the situation of mental health and violence against Brazilian children and adolescents, proposing a discussion about the need for public health policies including these extremely relevant issues in their priority agenda. In Brazil, the debate about this problem has occurred in a fragmented and not very consistent way. This article presents a non-systematic selection of epidemiological investigations on this subject conducted in Brazilian schools and communities. The great variety and prevalence of familiar and community violence and of mental health problems is pointed out and the methodological differences between the studies and the concentration of studies in the South and Southeastern regions of the country are emphasized. The article still highlights to the scarce service network for dealing with this kind of problem and the lack of concern with the prevention of mental disorders and promotion of mental health

From RFLP to DArT: molecular tools for wheat (Triticum spp.) diversity analysis

Wheat (Triticum spp.) is a universally lucrative agricultural crop. An increase in wheat production has been shown through selection by the farmers which can increase the grain profitability. The determination of genetic associations among domestic cultivars is facilitated by molecular markers. Data on genetic polymorphism is valuable for the germplasm association and regarding the developing management strategies. The information would be supportive for potential genome mapping programs and for the relevance of intellectual property rights of wheat breeders. Present review is an effort for providing support information to wheat breeders to develop varieties with varied genetic environment to attain continuity in large-scale wheat production. In this review, we have tried to provide a collective depiction of relevant information about the usage of some commonly used markers in wheat. It may help researchers to find out the frequentness and application of different markers and compare their results. The manuscript may serve as a platform helping the intellectuals for the selection and modification of their marker system in wheat diversity analysis. The heart of this review is the emphasis on the performance of various molecular genetic markers in diversity studies in relation to definite approaches that are in practice since several years allied with the multifaceted wheat molecular breeding and its polyploid nature