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Bioactive fungal metabolites
No full textFungi represent one of the seven kingdoms of living organisms [1] and their secondary metabolites display a
broad range of biological activities. We have recently reviewed those fungal metabolites that display anticancer
activity, both from terrestrial [2, 3] and marine [4] origins. We have also highlighted in these three reviews [2-4],
the currently known biological events that enable various types of cancers, including metastatic ones to display high
levels of chemoresistance. Some fungal metabolites are able to overcome certain of these biological barriers leading
to cancer chemoresistance. For example, fusicoccin A, isolated from Fusicoccum amygdali, down-regulates focal
adhesion kinase (FAK) activity and induces cytostatic activity in glioblastoma (GBM) cells [5]. Ophiobolin A, isolated from Bipolaris species, induces paraptosis in GBM cells through the disruption of internal potassium ion homeostasis [6]. GBM are highly chemoresistant [7] as melanomas against which sphaeropsidin A, isolated from Diplodia cupressi, also displays marked anticancer activity through the disruption of melanoma cell ion homeostasis
[8]. We recently highlighted in a special issue of Current Medicinal Chemistry, the potential of targeting ion channels / transporters to combat various types of cancers associated with dismal prognoses [9].
Fungal metabolite-related anticancer activity is further analyzed by two contributions in the current special issue.
Wolf-Rainer Abraham (Helmholtz Centre for Infection Research, Chemical Microbiology, Braunschweig, Germany) has contributed a review entitled “Fumitremorgins and Relatives – from Tremorgenic Compounds to Valuable Anti-Cancer Drugs”. Fumitremorgins are mycotoxins that can also inhibit cancer cell proliferation and impair
their drug resistance.
Cristina Prandi (Department of Chemistry, Universita’ degli Studi di Torino, Torino, Italy) and her collaborators
have contributed a review entitled “Fungal anticancer metabolites: synthesis towards drug discovery”. Prandi and
her colleagues highlight the role of total synthesis in sustaining the pharmacological development of fungal metabolites and as an alternative to isolation in the field of cancer research.
The current special issue then presents five other contributions that do not relate to anticancer activity of fungal
metabolites, while emphasizing a broad spectrum of other biological activities.
Peter Proksch (Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine-Universität Düsseldorf,
Düsseldorf, Germany) and his colleagues have contributed a review entitled “Natural Products from Deep-SeaDerived Fungi ̶ a New Source of Novel Bioactive Compounds?”. As reported by Proksch and colleagues, up to
now, over 200 new metabolites have been identified from deep-sea fungi, and it has been assumed in the literature
that the unique environment of the deep sea will give rise to equally unprecedented natural products. Proksch and
colleagues critically evaluate whether the data published so far really supports the notion that these fungi are a
promising source of new bioactive chemical entities.
Alessio Cimmino (Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Napoli, Italy) and his
colleagues have contributed a review entitled “Bioactive Metabolites from Pathogenic and Endophytic Fungi of
Forest Trees”. As emphasized by Cimmino and his colleagues, fungi play an important role in terrestrial ecosystems
by interacting positively or negatively with plants. Furthermore, temperate forests represent an enormous reservoir
of fungal diversity. The review provided by Cimmino and colleagues focuses on the secondary metabolites produced by pathogenic and endophytic fungi of forest trees with a focus on their biological activities.
Andrea Chini (Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología- Consejo Superior de Investigaciones Científicas, Madrid, Spain) and his colleagues have contributed a review entitled “Fungal
production and manipulation of plant hormones”. Chini and colleagues state that among the plant molecules that
regulate plant-fungus interactions, phytohormones play a critical role because they modulate various aspects of
plant development, defenses and stress responses. Chini and colleagues emphasize the fact that, intriguingly, fungi
can also produce phytohormones, although the actual role of fungal-produced phytohormones in plant-fungus interactions is poorly understood. Chini and colleagues thus provide an overview of the recent discoveries in fungal production of phytohormone, their putative role as endogenous fungal signals and how fungi manipulate plant hormone balance to their benefit.
Maurizio Vurro (Institute of Science of Food Production, National Research Council, Bari, Italy) and his colleagues have contributed a review entitled “Fungal Phytotoxins in Sustainable Weed Management”. Vurro and colleagues reevaluate the fact that fungal phytotoxins are natural secondary metabolites produced by plant pathogenic
fungi during host–pathogen interactions. The review provided by Vurro and colleagues aims to summarize studies
on the possibility of using such metabolites as tools in biological and integrated weed management, for example, as
novel and environmentally friendly herbicides; as biomarkers for the selection of more efficacious biocontrol
agents; as templates for novel compounds; and as sources of novel mechanisms of action. Vurro and colleagues also
discuss the limiting factors for utilizing these metabolites in practice.
Stefano Superchi (Dipartimento di Scienze, Università della Basilicata, Potenza, Italy) and his colleagues have
contributed a review entitled “Absolute Configuration Determination by Quantum Mechanical Calculation of Chiroptical Spectra: Basics and Applications to Fungal Metabolites”. Superchi and colleagues thus review the application of quantum mechanical simulations of chiroptical properties, i.e. electronic circular dichroism, optical rotation,
and vibrational circular dichroism, for the assignment of the absolute configuration of naturally occurring chiral metabolites of fungal origin.
REFERENCES
[1] Ruggiero, M.A.; Gordon, D.P.; Orrell, T.M.; Bailly, N.; Bourgoin, T.; Brusca, R.C.; Cavalier-Smith, T.; Guiry, M.D.; Kirk, P.M. A
higher level classification of all living organisms. PLoS One, 2015, 10, e0119248.
[2] Evidente, A.; Kornienko, A.; Cimmino, A.; Andolfi, A.; Lefranc, F.; Mathieu, V.; Kiss, R. Fungal metabolites with anticancer activity. Nat. Prod. Rep., 2014, 31, 617-627.
[3] Kornienko, A.; Evidente, A.; Vurro, M.; Mathieu, V.; Cimmino, A.; Evidente, M.; van Otterlo, W.A.; Dasari, R.; Lefranc, F.; Kiss, R.
Toward a cancer drug of fungal origin. Med. Res. Rev., 2015, 35, 937-67.
[4] Gomes, N.G.; Lefranc, F.; Kijjoa, A.; Kiss, R. Can some marine-derived fungal metabolites become actual anticancer agents? Mar.
Drugs, 2015, 13, 3950-3991.
[5] Bury, M.; Andolfi, A.; Rogister, B.; Cimmino, A.; Mégalizzi, V.; Mathieu, V.; Feron, O.; Evidente, A.; Kiss, R. Fusiccocin A, a phytotoxic carbotricyclic diterpene glucoside of fungal origin, reduces proliferation and invasion of glioblastoma cells by targeting multiple tyrosine kinases. Trans. Oncol., 2013, 6, 112-123.
[6] Bury, M.; Girault, A.; Mégalizzi, V.; Spiegl-Kreinecker, S.; Mathieu, V.; Berger, W.; Evidente, A.; Kornienko, A.; Gailly, P.; Vandier, C.; Kiss, R. Ophiobolin A induces paraptosis-like cell death in human glioblastoma cells by decreasing BKCa channel activity.
Cell Death Dis., 2013, 4, e561.
[7] Lefranc, F.; Brotchi, J.; Kiss, R. Possible future issues in the treatment of glioblastomas: special emphasis on cell migration and the
resistance of migrating glioblastoma cells to apoptosis. J. Clin. Oncol., 2005, 23, 2411-2422.
[8] Mathieu, V.; Chantôme, A.; Lefranc, F.; Cimmino, A.; Miklos, W.; Paulitschke, V.; Mohr, T.; Maddau, L.; Kornienko, A.; Berger,
W.; Vandier, C.; Evidente, A.; Delpire, E.; Kiss, R. Sphaeropsidin A shows promising activity against drug-resistant cancer cells by
targeting regulatory volume increase. Cell Mol. Life Sci., 2015, 72, 3731-3746.
[9] Kiss, R. Ion channels and cancers. Curr. Med. Chem., 2012, 19, 625-626
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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