1,720,973 research outputs found

    Cadmium accumulation in neuronal cells leads to essential metals imbalance and zinc transporters dysregulation

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    : The heavy metal cadmium (Cd), a natural element of the Earth's crust released into the environment through both natural processes and anthropogenic activities, is ranked 7th on the ATSDR Substance Priority List of hazardous substances. Its low excretion rate from human body and its long biological half-life (10-30 years) lead to Cd heavy accumulation in organisms. Although Cd carcinogenicity is well recognized, the neurotoxicity and damage to the nervous system still require further investigation. The interference with essential element homeostasis, referred as dyshomeostasis, is one of Cd neurotoxic mechanisms and its interference on specific ions balance could play a key role in the process of neurodegenerative diseases. In this study Cd possible impact on the balance of essential elements was evaluated in human neural SH-SY5Y cells, by exposing the target cells to low Cd concentrations (0.1-5μM) for 24h, 48h and 6 days. Cd accumulates inside the cells in a time and dose dependent manner with dysregulation of both zinc and iron homeostasis and induction of heme oxygenase 1 expression. Moreover, zinc transporters ZnT1 and ZnT2 are upregulated, while the iron transporter DMT1 is downregulated. In conclusion our data show that even low, sublethal cadmium concentrations are effective in inducing dyshomeostasis of essential metals involved in important neuronal functions

    Gratiola officinalis Alcoholic Extract Targets Warburg Effect, Apoptosis and Cell Cycle Progression in Colorectal Cancer Cell Lines

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    Colorectal cancer (CRC) is the second deadliest cancer in the Western world. Increased body weight, a diet rich in red meat and alcohol, as well as a sedentary lifestyle, are all involved in sporadic CRC pathogenesis. Since current CRC therapies show several side effects, there is a need to find new and more effective therapeutic approaches, allowing conventional drug dosages and toxicity to be reduced. Gratiola officinalis alcoholic extract was characterized by LC-MS and its effect investigated on a healthy colon mucosa cell line and on different colorectal cancer cell lines. Cell viability, apoptosis and cell cycle progression were evaluated through flow cytometry; energy production and glycolysis were investigated using Seahorse technology, while cancer markers were analyzed through Western blotting. The untargeted metabolomics analysis of G. officinalis alcoholic extract revealed glycosides of different polyphenols and glycosides of cucurbitane-type triterpenes. This extract showed a stronger impact on CRC cell line viability compared to healthy colon cells. In the E705 CRC cell line, it induced cell apoptosis and caused the downregulation of glycolysis, inhibiting cell proliferation. On the other hand, SW480 CRC cells treated with G. officinalis extract showed G2/M cell cycle arrest. This work shows that G. officinalis extract can reduce glycolysis and promote cell cycle arrest in CRC cells, suggesting that G. officinalis could represent a novel player in the prevention and treatment of CRC

    Non-small cell lung cancer (NSCLC), EGFR downstream pathway activation and TKI targeted therapies sensitivity: Effect of the plasma membrane-associated NEU3.

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    Adenocarcinoma of Non-Small Cell Lung Cancer (NSCLC) is a severe disease. Patients carrying EGFR mutations may benefit from EGFR targeted therapies (e.g.: gefitinib). Recently, it has been shown that sialidase NEU3 directly interacts and regulates EGFR. In this work, we investigate the effect of sialidase NEU3 overexpression on EGFR pathways activation and EGFR targeted therapies sensitivity, in a series of lung cancer cell lines. NEU3 overexpression, forced after transfection, does not affect NSCLC cell viability. We demonstrate that NEU3 overexpression stimulates the ERK pathway but this activation is completely abolished by gefitinib treatment. The Akt pathway is also hyper-activated upon NEU3 overexpression, but gefitinib is able only to decrease, and not to abolish, such activation. These findings indicate that NEU3 can act directly on the ERK pathway through EGFR and both directly and indirectly with respect to EGFR on the Akt pathway. Furthermore, we provide evidence that a healthy mucosa cell line (with EGFR wild-type gene sequence) is slightly sensitive to gefitinib, especially in the presence of NEU3 overexpression, thus hypothesizing that NEU3 overexpressing patients may benefit from EGFR targeted therapies also in absence of EGFR point mutations. Overall, the expression of NEU3 may be a novel diagnostic marker in NSCLC because, by its ability to stimulate EGFR downstream pathways with direct and indirect mechanisms, it may help in the identification of patients who can profit from EGFR targeted therapies in absence of EGFR activating mutations or from new combinations of EGFR and Akt inhibitors

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Methanolic Extract of the Nutritional Plant (Diospyros kaki Thunb.) Exhibits Anticancer Activity by Inducing Mitochondrial Dysfunction in Colorectal Cancer Cells

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    Background/Objectives: Diospyros kaki, the most widely cultivated species of persimmon, has been long used in traditional medicine since its leaves’ extracts contain high amounts of flavonoids and terpenoids, endowed with several beneficial effects. However, its anticancer activity towards colorectal cancer (CRC) has not been investigated in depth. Methods: The effect of a methanolic extract of D. kaki leaves, rich in kaempferol and quercetin derivatives, have been evaluated on an E705 CRC cell line, representative of most CRC patients, and on SW480 cells, carrying a KRAS-activating mutation. Results: This extract is effective in reducing tumor cells’ viability without affecting the healthy mucosa cell line CCD 841. In fact, Western blot experiments showed its ability to induce apoptosis in cancer cells by increasing oxidative stress and disrupting mitochondrial functionality, as shown by reactive oxygen species measurement and Seahorse analysis. Conclusions: With the aim of increasing healthspan, as well as the substantial societal and macroeconomic costs associated with cancer, our results could pave the way to a role for D. kaki extract in both CRC treatment and prevention

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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