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Abstract: Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and is associated with various clinico-pathological characteristics such as genetic mutations and viral infections. Therefore, numerous laboratories look out for identifying always new putative markers for the improvement of HCC diagnosis/prognosis. Many molecular profiling studies investigated gene expression changes related to HCC. HepG2 represents a pure cell line of human liver carcinoma, often used as HCC model due to the absence of viral infection. In this study we compare gene expression profiles associated with HepG2 (as HCC model) and normal hepatocyte cells by microarray technology. Hierarchical cluster analysis of genes evidenced that 2646 genes significantly down-regulated in HepG2 cells compared to hepatocytes whereas a further 3586 genes significantly up-regulated. By using the Ingenuity Pathway Analysis (IPA) program, we have classified the genes that were differently expressed and studied the functional networks correlating these genes in the complete human interactome. Moreover, to confirm the differentially expressed genes as well as the reliability of our microarray data, we performed a quantitative Real time RT-PCR analysis on 9 up-regulated and 11 down-regulated genes, respectively. In conclusion this work i) provides a gene signature of human hepatoma cells showing genes that change their expression as a consequence of liver cancer in the absence of any genetic mutations or viral infection, ii) evidences new differently expressed genes found in our signature compared to previous published studies and iii) suggests some genes on which to focus future studies to understand if they can be used to improve the HCC prognosis/diagnosis. [Copyright &y& Elsevier]

Abstract: Recently several experiments improved significantly our knowledge of cosmic ray (CR) spectra at high energy. In particular CREAM measured B/C, C/O and N/O ratios up to and PAMELA observed the antiproton-to-proton ratio up to with high accuracy. These results permit to put more stringent constraints on the free parameters involved in the diffusion-loss equation that describes the propagation of CRs in the Galaxy. To this purpose, we perform a new statistical analysis comparing updated experimental data with the predictions of an improved version of our numerical code DRAGON. We obtain well defined ranges of values for the diffusion coefficient normalization and index of the power-law dependence on rigidity as well as for the Alfvén velocity. [Copyright &y& Elsevier]

DNA is widely used as a target for GMO analysis because of its stability and high detectability. Real-time PCR is the method routinely used in most analytical laboratories due to its quantitative performance and great sensitivity. Accurate DNA detection and quantification is dependent on the specificity and sensitivity of the amplification protocol as well as on the quality and quantity of the DNA used in the PCR reaction. In order to enhance the sensitivity of real-time PCR and consequently expand the number of analyzable target genes, we applied a preamplification technique to processed foods where DNA can be present in low amounts and/or in degraded forms thereby affecting the reliability of qualitative and quantitative results. The preamplification procedure utilizes a pool of primers targeting genes of interest and is followed by real-time PCR reactions specific for each gene. An improvement of Ct values was found comparing preamplified vs. non-preamplified DNA. The strategy reported in the present study will be also applicable to other fields requiring quantitative DNA testing by real-time PCR. [ABSTRACT FROM AUTHOR]

Abstract: The Fermi Large Area Telescope (LAT) recently measured the cosmic ray electrons-plus-positrons (CRE) spectrum between 20GeV and 1TeV. In this contribution we discuss several interpretations of those measurements in combination with other experimental data. We show that, as far as concerns the reported Fermi-LAT data alone, a simple interpretation invoking a single class of astrophysical electron sources is possible. If, however, also the CRE spectrum measured by H.E.S.S. and especially the positron fraction reported by PAMELA are accounted, that scenario fails to provide a combined description of those results. Rather, we show that several combinations of parameters, involving pair emission by pulsars or dark matter annihilation, allow a consistent interpretation of all data sets. [Copyright &y& Elsevier]

Abstract: The Fermi-LAT experiment recently reported high precision measurements of the spectrum of cosmic-ray electrons-plus-positrons (CRE) between 20GeV and 1TeV. The spectrum shows no prominent spectral features, and is significantly harder than that inferred from several previous experiments. Here we discuss several interpretations of the Fermi results based either on a single large scale Galactic CRE component or by invoking additional electron–positron primary sources, e.g. nearby pulsars or particle dark matter annihilation. We show that while the reported Fermi-LAT data alone can be interpreted in terms of a single component scenario, when combined with other complementary experimental results, specifically the CRE spectrum measured by H.E.S.S. and especially the positron fraction reported by PAMELA between 1 and 100GeV, that class of models fails to provide a consistent interpretation. Rather, we find that several combinations of parameters, involving both the pulsar and dark matter scenarios, allow a consistent description of those results. We also briefly discuss the possibility of discriminating between the pulsar and dark matter interpretations by looking for a possible anisotropy in the CRE flux. [Copyright &y& Elsevier]