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Antiproliferative activities of chalepin and rutamarin isolated from Ruta angustifolia on selected cancer cell lines / Musa Isah Fakai
Get PDFChalepin and rutamarin isolated from the chloroform fraction of Ruta angustifolia were screened against selected cancer lines namely the human hormone-dependent breast cancer cell (MCF7), human non-hormone-dependent breast cancer cell (MDA-MB-231), human colon cancer cell (HT29), human colon carcinoma cell (HCT116) and a normal lung fibroblast cell line (MRC-5). Phytochemical investigation on the active chloroform extract led to the isolation of chalepin and rutamarin using HPLC. These compounds were then, identified by GC-MS and NMR analysis. This was followed by cytotoxicity screening using SRB assay. Based on the IC50 at the lower time point, chalepin was further investigated for its apoptotic induction on MCF7 cell through morphological analysis using both phase contrast and fluorescence microscopy; and established biochemical assays. Western blot analysis was also conducted on MCF7 treated with chalepin. For HT29 cells, rutamarin treatment followed by downstream study on protein profiling by LC-MS approach as well as western blot analysis was performed as there were no previously reported study. The active chloroform extract showed relatively higher cytotoxic activity against MCF7, MDA-MB-231, and HT29, but no activity against MRC5 (IC50 > 100g/mL). Chalepin displayed remarkable cytotoxicity against all tested cancer cell lines but no activity against MRC-5. Rutamarin on the other hand, showed remarkable cytotoxic activity only on MCF7 and HT29, whereas no activity against MDA-MB-231 and MRC5 was observed. In this study, morphological examinations identified typical apoptotic features such as membrane blebbing, chromatin condensation, DNA fragmentation, and apoptotic body formation. Phosphatidylserine externalisations, DNA fragmentation, and caspase-3 activity significantly increased whereas mitochondrial membrane potential significantly decreased in chalepin treated MCF7 cells as compared to untreated cells. Western blots results showed that the expression of pro-apoptotic proteins such as caspases, Bid and P53 were upregulated whereas cell cycle regulatory proteins such as CDK2, CDK4, cyclin A, and cyclin D were downregulated. Similarly, EGFR and its downstream cascades; (PI3K-AKT; JAK-STAT3 and Erk pathways) were also downregulated. The apoptotic effect of chalepin against MCF7 was a dose and time-dependent manner. On the other hand, Western blot results on HT29 treated with rutamarin shows that the expression of pro-apoptotic proteins such as caspases, Bid, P21, P27, and P53 was upregulated whereas cell cycle regulatory proteins such as CDK2, CDK4, cyclin A, and cyclin D were downregulated. Similarly, EGFR and its downstream cascades (PI3K-AKT; JAK-STAT3 and Erk pathways) were also downregulated. Results from proteomic profiling indicates that 2056 proteins were identified from both untreated and 6 hours rutamarin treated HT29. Following filtrations, at various levels, only 756 proteins were used for the analysis. Consequently, two sample t-test show that only one protein; mitochondrial carrier homolog 2 (MTCH2) (Q9Y6C9) was identified to be upregulated in 6 hours, whereas profile plot analysis indicated 20 proteins are having a similar pattern including the differentially expressed protein. These initial results, therefore suggest that chalepin and rutamarin may serve as potential anticancer agents that warrant further in-depth investigations
Chalepin and rutamarin isolated from Ruta angustifolia inhibit cell growth in selected cancer cell lines (MCF7, MDA-MB-231, HT29, and HCT116)
No full textMany anticancer drugs have their origin in natural sources like plants. In this
study, extracts from Ruta angustifolia were screened against four (4) selected cancer cell
lines and a normal lung fibroblast cell line (MRC-5). The chloroform extract showed higher
cytotoxic activity against MCF7, HT29, HCT116, but mild cytotoxicity against MDA-MB231
and no activity against MCR5 (IC50 > 100?g/mL). Chalepin and rutamarin were then
isolated from the active chloroform extract. Chalepin displayed remarkable cytotoxicity
against all tested cancer cell lines but no activity against MCR5. Rutamarin, on the other
hand, showed remarkable cytotoxicity activity against MCF7, HT29, and HCT116, whereas
no activity against MDA-MB-231 and MRC5 was observed. The present study therefore
revealed that chalepin and rutamarin inhibit cell growth against cancer cell lines in a dose
and time-dependent manner. These initial results, therefore, suggests that chalepin and
rutamarin may serve as potential source of anticancer agents
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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