12,079 research outputs found

    Evolution of cooperation among tumor cells

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    The evolution of cooperation has a well established theoretical framework based on game theory. This approach has made valuable contributions to a wide variety of disciplines, including political science, economics, and evolutionary biology. Existing cancer theory suggests that individual clones of cancer cells evolve independently from one another, acquiring all of the genetic traits or hallmarks necessary to form a malignant tumor. It is also now recognized that tumors are heterotypic, with cancer cells interacting with normal stromal cells within the issue microenvironment, including endothelial, stromal, and nerve cells. This tumor cell???stromal cell interaction in itself is a form of commensalism, because it has been demonstrated that these nonmalignant cells support and even enable tumor growth. Here, we add to this theory by regarding tumor cells as game players whose interactions help to determine their Darwinian fitness. We marshal evidence that tumor cells overcome certain host defenses by means of diffusible products. Our original contribution is to raise the possibility that two nearby cells can protect each other from a set of host defenses that neither could survive alone. Cooperation can evolve as byproduct mutualism among genetically diverse tumor cells. Our hypothesis supplements, but does not supplant, the traditional view of carcinogenesis in which one clonal population of cells develops all of the necessary genetic traits independently to form a tumor. Cooperation through the sharing of diffusible products raises new questions about tumorigenesis and has implications for understanding observed phenomena, designing new experiments, and developing new therapeutic approaches.Author manuscript. Published in final edited form as: Proc Natl Acad Sci U S A. 2006 September 5; 103(36): 13474-13479.The final published version of this article is located at: www.pnas.org/cgi/doi/10.1073/pnas.0606053103NIH U56 CA113004; to David E. AxelrodR.A. was supported by National Science Foundation (NSF) Grant SES-0240852. D.E.A. was supported by NSF Grant IIS-0312953, National Institutes of Health (NIH) Grant U56 CA113004, and New Jersey Commission on Cancer Research Grant 1076-CCR-SO. K.J.P. is an American Cancer Society Clinical Research Professor and is supported by NIH Grants CA69568, CA102872, and CA093900.NIH CA69568; to Kenneth J. PientaNIH CA102872; to Kenneth J. PientaNIH CA093900; to Kenneth J. PientaNSF SES-0240852; to Robert AxelrodNJ Commission on Cancer Research 1076-CCR-SO; to David E. AxelrodAlso available in PubMed Central. PMCID: PMC155738

    Colon_Crypt_Model_041321.nlogo

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    Title: Colon_Crypt_Model_041321.nlogo Research genre: Computer program Creator: Axelrod, David E. Date Created: 2021 Extent: 1 digital file (393 KB) Intended Audience: Science Description: Computer program that simulates and plots the dynamics of stem cells, transient amplifying cells, differentiated cells, and mutant cells in normal human colon crypts and early colon cancer. It has been calibrated with measurements of human biopsy specimens. Includes graphical user interface, detailed information text, and annotated code. Experiments can be run from the GUI without knowledge of coding, or from the Behavior Space Tool using example code or modified code. It has been used to simulate human colon cancer initiation, therapy, and prevention. Different chemotherapy or prevention intermittent dose schedules can be input. Chemotherapy of heterogeneous and drug resistant early colon cancers can be simulated. Circadian cell proliferation can be selected to investigate chronomodulated chemotherapy dose schedules. Simulated output can be saved in spreadsheet format, or as images of plots of cell numbers as function of time. The model was developed in the application NetLogo version 5.3.1, and revisions made to also run in NetLogo version 6.2.0. The model will not run on the Web version of NetLogo. NetLogo is a multi-agent programmable modeling environment. It is authored by Uri Wilenski and developed at The Center for Connected Learning (CCL) and Computer-Based Modeling. It is multi-platform (Mac, Windows, or Linux) open source application. NetLogo version 6.2.0, can be downloaded at http://ccl.northwestern.edu/netlogo/download.shtml. To download the computer program click on the red link “NLOGO" to the left. Earlier versions of the model and its use have been described in the following publications: Theoret Biol Med Model. 2013;10:66-89. Cancer Chemother Pharmcol 2017;79:889-898. Converg Sci Phys Oncol 2017;3:035004. Cancer Inform 2019;18:1-8. JCO Clin Cancer Inform 2020;4:514-520. A forthcoming publication will describe results of circadian-timed chemotherapy. Research Domain: Science Subjects: Chronotherapy: Circadian: Colorectal cancer: Chemotherapy: Agent-based model Rights statement: The author owns the copyright to this work

    Disputatio philosophica de dependentia creaturae a Deo in esse, fieri, et operari

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    quam auspice Deo , sub praesidio Dn. Ioh. Rod. Ottii ... amico examini subiicit David Holzhalbius author & respondens ...Diss. Hohe Schule Zürich, 169

    Integrative Genomics and Network Biology in Livestock and other Domestic Animals

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    This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contac

    E-book : Industrial Transformation In The Developing World (author: Michael T. Rock & David P. Angel)

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    Arsip Kuliah Online 2010: E-book : Industrial Transformation In The Developing World (author: Michael T. Rock & David P. Angel

    E-book : "industrial Transformations In The Developing World (author: Michael T. Rock & David. P Angel)

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    Arsip Kuliah Online 2010: E-book : "industrial Transformations In The Developing World (author: Michael T. Rock & David. P Angel

    Landsat MSS classification of fire fuel types in Wood Buffalo National Park, northern Canada

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    J1: Global Ecology & Biogeography Letters; M3: Article; Milne, David Franklin, Steven E. Wilson, Bradley A. Ghitter, Geoff Heathcott, Mark McCaffrey, Thomas M. Ow, Charlotte F. Y.; Source Information: Mar1994, Vol. 4 Issue 2, p33; Subject Term: FOREST fires; Author-Supplied Keyword: Canada (Wood Buffalo National Park); Author-Supplied Keyword: Forest fire; Author-Supplied Keyword: Fuel type classification; Author-Supplied Keyword: Landsat data; Number of Pages: 0p; Document Type: Articl

    David Audretsch: A Source of Inspiration, a Co-author, and a Friend

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    In this chapter, Enrico Santarelli discusses the profound impact that David had on his career. Beginning with a conference in Budapest, Santarelli and David bocame close friends and colleagues. They went on to collaborate on many papers and projects, several of which Santarelli highlights below

    The Arts Interview. Dr. David Pitt : The Truant Years, E. J. Pratt

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    Host Fred Hollingshurst interviews Dr. David Pitt of Memorial University, who discusses the life and work of Newfoundland poet E. J. Pratt. Pitt is the author of E. J. Pratt: The Truant Years, 1881-1927

    The future of scholarly communications

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    The academic publishing industry is set to celebrate 350 years of peer-reviewed scientific journals. However, there are significant shifts in the practice of scholarship, as scholars and citizens alike participate in an increasingly digital world. Is the scholarly article still fit for its purpose in this data-driven world, with new interdisciplinary methodologies and increasing automation? How might it be enhanced or replaced with new kinds of digital research objects , so as not to restrict innovation but rather create a flourishing sense-making network of humans and machines? The emerging paradigm of social machines provides a lens onto future developments in scholarship and scholarly collaboration, as we live and study in a hybrid physical-digital sociotechnical system of enormous and growing scale.Copyright 2014 David De Roure. This is an open access article distributed under the terms of the Creative Commons Attribution Licence, http://creativecommons.org/licenses/by/4.0/ which permits unrestricted use and distribution provided the original author and source are credited. If reusing please acknowledge "Insights: the UKSG journal" as the place of first publication. Please cite using the full DOI as specified at the end of the article: De Roure, D, The future of scholarly communications, Insights, 2014, 27(3), 233–238; DOI: http://dx.doi.org/10.1629/2048-7754.17
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