Evaluating anaphora and coreference resolution to improve automatic keyphrase extraction

In this paper we analyze the effectiveness of using linguistic knowledge from coreference and anaphora resolution for improving the performance for supervised keyphrase extraction. In order to verify the impact of these features, we de\ufb01ne a baseline keyphrase extraction system and evaluate its performance on a standard dataset using different machine learning algorithms. Then, we consider new sets of features by adding combinations of the linguistic features we propose and we evaluate the new performance of the system. We also use anaphora and coreference resolution to transform the documents, trying to simulate the cohesion process performed by the human mind. We found that our approach has a slightly positive impact on the performance of automatic keyphrase extraction, in particular when considering the ranking of the results

How Blue Light Activates Furocoumarin Derivatives Triggering Tumor Cell Apoptosis

Furocoumarins comprise natural and synthetic compounds: linear molecules, so called psoralens, and the angular ones, the angelicins. The photobiological effects of furocoumarins plus UVA are mainly related to their capacity to bind DNA and form monoadducts (MAs) and interstrand crosslinks (XLs), mainly with pyrimidine bases. Furthermore, furocoumarins produce ROS that impair cellular functions through lipid peroxidation, oxidation of guanine and strand breaks in nucleic acids, oxidation of proteins and inactivation of enzymes. It is known that the combination of 8-MOP and UVA radiation causes apoptosis of treated leucocytes and may cause preferential apoptosis of activated or abnormal T cells. Moreover, these apoptotic cells may promote immune tolerance, production of antigen-specific regulatory lymphocytes (CD4/8 T, B) and rebalance of immune system. Even though furocoumarins possess high chemotherapeutic potency under UVA and lack toxicity in the dark, genotoxicity, mutagenicity and skin phototoxicity have been observed. 8-MOP was found to photoreact under blue light (BL), leading to less mutagenic lesions in the DNA, that is preferentially MAs over XLs. Furthermore, cells treated with 419 nm light resumed normal growth rates faster than cells which received the same UVA dose

4,6,4′-Trimethylangelicin Photoactivated by Blue Light Might Represent an Interesting Option for Photochemotherapy of Non-Invasive Bladder Carcinoma: An In Vitro Study on T24 Cells

Photodynamic therapy (PDT) is frequently used to treat non-muscle invasive bladder cancer due its low toxicity and high selectivity. Since recurrence often occurs, alternative approaches and/or designs of combined therapies to improve PDT effectiveness are needed. This work aimed to evaluate the cytotoxicity of 4,6,4′-trimethylangelicin (TMA) photoactivated by blue light (BL) on human bladder cancer T24 cells and investigate the mechanisms underlying its biological effects. TMA/BL exerted antiproliferative activity through the induction of apoptosis without genotoxicity, as demonstrated by the expression levels of phospho-H2AX, an indicator of DNA double-stranded breaks. It also modulated the Wnt canonical signal pathway by increasing the phospho-β-catenin and decreasing the nuclear levels of β-catenin. The inhibition of this pathway was due to the modulation of the GSK3β phosphorylation state (Tyr 216) that induces a proteasomal degradation of β-catenin. Indeed, a partial recovery of nuclear β-catenin expression and reduction of its phosphorylated form after treatment with LiCl were detected. As demonstrated by RT-PCR and cytofluorimetric analysis, TMA/BL also decreased the expression of CD44v6, a marker of cancer stem cells. Taken together, our data suggest that TMA photoactivated by BL may represent an interesting option for the photochemotherapy of noninvasive bladder carcinomas, since this treatment is able to inhibit key pathways for tumour growth and progression in the absence of genotoxic effects

4,6,4′-Trimethylangelicin Photoactivated by Blue Light Might Represent an Interesting Option for Photochemotherapy of Non-Invasive Bladder Carcinoma: An In Vitro Study on T24 Cells

Photodynamic therapy (PDT) is frequently used to treat non-muscle invasive bladder cancer due its low toxicity and high selectivity. Since recurrence often occurs, alternative approaches and/or designs of combined therapies to improve PDT effectiveness are needed. This work aimed to evaluate the cytotoxicity of 4,6,4′-trimethylangelicin (TMA) photoactivated by blue light (BL) on human bladder cancer T24 cells and investigate the mechanisms underlying its biological effects. TMA/BL exerted antiproliferative activity through the induction of apoptosis without genotoxicity, as demonstrated by the expression levels of phospho-H2AX, an indicator of DNA double-stranded breaks. It also modulated the Wnt canonical signal pathway by increasing the phospho-β-catenin and decreasing the nuclear levels of β-catenin. The inhibition of this pathway was due to the modulation of the GSK3β phosphorylation state (Tyr 216) that induces a proteasomal degradation of β-catenin. Indeed, a partial recovery of nuclear β-catenin expression and reduction of its phosphorylated form after treatment with LiCl were detected. As demonstrated by RT-PCR and cytofluorimetric analysis, TMA/BL also decreased the expression of CD44v6, a marker of cancer stem cells. Taken together, our data suggest that TMA photoactivated by BL may represent an interesting option for the photochemotherapy of noninvasive bladder carcinomas, since this treatment is able to inhibit key pathways for tumour growth and progression in the absence of genotoxic effects

Antiproliferative activity of 8-methoxypsoralen on DU145 prostate cancer cells under UVA and blue light

The use of photoactivatable 8-methoxypsoralen (8-MOP) as potential focal treatment towards prostate cancer cells is proposed here. Our results, obtained on isolated DNA and DU145 cells, indicate that blue light, besides UVA, is able to activate 8-MOP. When compared to UVA, blue light irradiation led to a modulation of the extent and the types of 8-MOP-DNA damage, specially cross-links, coupled to a still valuable antiproliferative effect. Our data suggest that the proapototic activity of 8-MOP is related not only to DNA damage and reactive oxygen species generation but also to the modulation of cell signalling pathways. In particular, a different activation of p38 and p44/42 mitogen-activated protein kinases was detected depending on the light wavelengths