1
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Millett P, Alexanian T, Brink KR, Carter SR, Diggans J, Palmer MJ, Ritterson R, Sandbrink JB, Wheeler NE. Beyond Biosecurity by Taxonomic Lists: Lessons, Challenges, and Opportunities. Health Secur 2023; 21:521-529. [PMID: 37856148 PMCID: PMC10733751 DOI: 10.1089/hs.2022.0109] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023] Open
Affiliation(s)
- Piers Millett
- Piers Millett, PhD, is Executive Director, International Biosecurity and Biosafety Initiative for Science, Washington, DC
| | - Tessa Alexanian
- Tessa Alexanian is Safety and Security Program Officer, iGEM Foundation, Paris, France
| | - Kathryn R. Brink
- Kathryn R. Brink, PhD, is a Postdoctoral Fellow, Center for International Security and Cooperation, at Stanford University, Stanford, CA
| | - Sarah R. Carter
- Sarah R. Carter, PhD, is Principal, Science Policy Consulting LLC, Arlington, VA
| | - James Diggans
- James Diggans, PhD, is Head of Biosecurity, Twist Bioscience, San Francisco, CA
| | - Megan J. Palmer
- Megan J. Palmer, PhD, is Executive Director of Bio Policy & Leadership Initiatives and an Adjunct Professor, Department of Bioengineering; at Stanford University, Stanford, CA
| | - Ryan Ritterson
- Ryan Ritterson, PhD, is Executive Vice President of Research, Gryphon Scientific LLC, Takoma Park, MD
| | - Jonas B. Sandbrink
- Jonas B. Sandbrink is a Doctoral Researcher, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Nicole E. Wheeler
- Nicole E. Wheeler, PhD, is a Turing Fellow, Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
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2
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Greene D, Palmer MJ, Relman DA. Motivating Proactive Biorisk Management. Health Secur 2023; 21:46-60. [PMID: 36633603 PMCID: PMC9940813 DOI: 10.1089/hs.2022.0101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 10/29/2022] [Accepted: 11/03/2022] [Indexed: 01/13/2023] Open
Abstract
Scholars and practitioners of biosafety and biosecurity (collectively, biorisk management or BRM) have argued that life scientists should play a more proactive role in monitoring their work for potential risks, mitigating harm, and seeking help as necessary. However, most efforts to promote proactive BRM have focused on training life scientists in technical skills and have largely ignored the extent to which life scientists wish to use them (ie, their motivation). In this article, we argue that efforts to promote proactive BRM would benefit from a greater focus on life scientists' motivation. We review relevant literature on life scientists' motivation to practice BRM, offer examples of successful interventions from adjacent fields, and outline ideas for possible interventions to promote proactive BRM, along with strategies for iterative development, testing, and scaling.
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Affiliation(s)
- Daniel Greene
- Daniel Greene, PhD, is a Senior Analyst, Biosafety, Biosecurity & Emerging Technologies, Gryphon Scientific, Takoma Park, MD. Daniel Greene is also a Postdoctoral Fellow, Center for International Security and Cooperation; Stanford University, Stanford, CA
| | - Megan J. Palmer
- Megan J. Palmer, PhD, is Executive Director, Bio Policy & Leadership Initiatives, and an Adjunct Professor, Department of Bioengineering; Stanford University, Stanford, CA
| | - David A. Relman
- David A. Relman, MD, is a Senior Fellow, Center for International Security and Cooperation; Stanford University, Stanford, CA. David A. Relman is also the Thomas C. and Joan M. Merigan Professor, Departments of Medicine, and of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA
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3
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Pannu J, Palmer MJ, Cicero A, Relman DA, Lipsitch M, Inglesby T. Strengthen oversight of risky research on pathogens. Science 2022; 378:1170-1172. [PMID: 36480598 DOI: 10.1126/science.adf6020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Policy reset and convergence on governance are needed.
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Affiliation(s)
- Jaspreet Pannu
- Center for Health Security, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Megan J Palmer
- Department of Bioengineering, Stanford University, Stanford, CA, USA.,Center for International Security and Cooperation, Freeman Spogli Institute for International Studies, Stanford University, Stanford, CA, USA
| | - Anita Cicero
- Center for Health Security, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - David A Relman
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.,Center for International Security and Cooperation, Freeman Spogli Institute for International Studies, Stanford University, Stanford, CA, USA.,Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA.,Infectious Diseases Section, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA
| | - Marc Lipsitch
- Center for Communicable Disease Dynamics, Departments of Epidemiology and Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Tom Inglesby
- Center for Health Security, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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4
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Mackelprang R, Adamala KP, Aurand ER, Diggans JC, Ellington AD, Evans SW, Fortman JLC, Hillson NJ, Hinman AW, Isaacs FJ, Medford JI, Mamaghani S, Moon TS, Palmer MJ, Peccoud J, Vitalis EA, Hook-Barnard I, Friedman DC. Making Security Viral: Shifting Engineering Biology Culture and Publishing. ACS Synth Biol 2022; 11:522-527. [PMID: 35176864 DOI: 10.1021/acssynbio.1c00324] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability to construct, synthesize, and edit genes and genomes at scale and with speed enables, in synergy with other tools of engineering biology, breakthrough applications with far-reaching implications for society. As SARS-CoV-2 spread around the world in early spring of 2020, researchers rapidly mobilized, using these tools in the development of diagnostics, therapeutics, and vaccines for COVID-19. The sharing of knowledge was crucial to making rapid progress. Several publications described the use of reverse genetics for the de novo construction of SARS-CoV-2 in the laboratory, one in the form of a protocol. Given the demonstrable harm caused by the virus, the unequal distribution of mitigating vaccines and therapeutics, their unknown efficacy against variants, and the interest in this research by laboratories unaccustomed to working with highly transmissible pandemic pathogens, there are risks associated with such publications, particularly as protocols. We describe considerations and offer suggestions for enhancing security in the publication of synthetic biology research and techniques. We recommend: (1) that protocol manuscripts for the de novo synthesis of certain pathogenic viruses undergo a mandatory safety and security review; (2) that if published, such papers include descriptions of the discussions or review processes that occurred regarding security considerations in the main text; and (3) the development of a governance framework for the inclusion of basic security screening during the publication process of engineering biology/synthetic biology manuscripts to build and support a safe and secure research enterprise that is able to maximize its positive impacts and minimize any negative outcomes.
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Affiliation(s)
- Rebecca Mackelprang
- Engineering Biology Research Consortium, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Katarzyna P. Adamala
- Department of Genetics, Cell Biology and Development, University of Minnesota, 420 Washington Avenue SE, Minneapolis, Minnesota 55455, United States
| | - Emily R. Aurand
- Engineering Biology Research Consortium, 5885 Hollis Street, Emeryville, California 94608, United States
| | - James C. Diggans
- Twist Bioscience, 681 Gateway Boulevard, South San Francisco, California 94080, United States
| | - Andrew D. Ellington
- Center for Systems and Synthetic Biology, University of Texas at Austin, 100 E 24th Street, Austin, Texas 78712, United States
| | - Samuel Weiss Evans
- Harvard Kennedy School, Program on Science, Technology & Society, 79 JFK Street, Cambridge, Massachusetts 02139, United States
| | - J. L. Clem Fortman
- Engineering Biology Research Consortium, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Nathan J. Hillson
- Biological Systems & Engineering Division, Berkeley National Lab, 1 Cyclotron Road, Berkeley, California 94720, United States
- DOE Agile BioFoundry, 1 Cyclotron Road, Berkeley, California 94720, United States
- DOE Joint Genome Institute,1 Cyclotron Road, Berkeley, California 94720, United States
- DOE Joint BioEnergy Institute, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Albert W. Hinman
- Engineering Biology Research Consortium, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Farren J. Isaacs
- Department of Molecular, Cellular & Developmental Biology, Department of Biomedical Engineering, Systems Biology Institute, Yale University, 266 Whitney Avenue, KBT 802, P.O. Box 208103, New Haven, Connecticut 06520, United States
| | - June I. Medford
- Department of Biology, Colorado State University, 1878 Campus Delivery, Fort Collins, Colorado 90523-1878, United States
| | - Shadi Mamaghani
- AAAS Science and Technology Policy Fellowship, 1200 NW New York Avenue, Washington, D.C., 20005, United States
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, One Brookings Drive Box 1180, St. Louis, Missouri 63130, United States
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, One Brookings Drive Box 1180, St. Louis, Missouri 63130, United States
| | - Megan J. Palmer
- Department of Bioengineering, Stanford University, 443 Via Ortega, Stanford, California 94305, United States
- Center for International Security and Cooperation, Freeman Spogli Institute for International Studies, Stanford University, 616 Serra Street C100, Stanford, California 94305, United States
| | - Jean Peccoud
- Department of Chemical & Biological Engineering, Colorado State University, 1370 Campus Delivery, Fort Collins, Colorado 80523-1370, United States
| | | | - India Hook-Barnard
- Engineering Biology Research Consortium, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Douglas C. Friedman
- Engineering Biology Research Consortium, 5885 Hollis Street, Emeryville, California 94608, United States
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5
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Macdowall WG, Clifton S, Palmer MJ, Tanton C, Copas AJ, Lee DM, Mitchell KR, Mercer CH, Sonnenberg P, Johnson AM, Wellings K. Salivary Testosterone and Sexual Function and Behavior in Men and Women: Findings from the Third British National Survey of Sexual Attitudes and Lifestyles (Natsal-3). J Sex Res 2022; 59:135-149. [PMID: 34634954 PMCID: PMC7613951 DOI: 10.1080/00224499.2021.1968327] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Using data from the third British National Survey of Sexual Attitudes and Lifestyles (Natsal-3) we examined associations between salivary testosterone (Sal-T) and sexual function and behavior. Single morning saliva samples were self-collected from a subsample of participants aged 18-74 years and analyzed using mass spectrometry. 1,599 men and 2,123 women were included in the analysis (40.6% of those invited to provide a sample). We adjusted for confounders in a stepwise manner: in model 1 we adjusted for age only; model 2 for age, season and relationship status, and model 3 we added BMI and self-reported health. In the fully adjusted models, among men, Sal-T was positively associated with both partnered sex (vaginal sex and concurrent partners) and masturbation. Among women, Sal-T was positively associated with masturbation, the only association with partnered sex was with ever experience of same-sex sex. We found no clear association between Sal-T and sexual function. Our study contributes toward addressing the sparsity of data outside the laboratory on the differences between men and women in the relationship between T and sexual function and behavior. To our knowledge, this is the first population study, among men and women, using a mass spectrometry Sal-T assay to do so.
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Affiliation(s)
- W G Macdowall
- Department of Public Health, Environments and Society, Faculty of Public Health and Policy, London School of Hygiene & Tropical Medicine
| | - S Clifton
- Institute for Global Health, University College London, Mortimer Market Centre
- NatCen Social Research
| | - M J Palmer
- Department of Public Health, Environments and Society, Faculty of Public Health and Policy, London School of Hygiene & Tropical Medicine
| | - C Tanton
- Department of Global Health and Development, Faculty of Public Health and Policy, London School of Hygiene & Tropical Medicine
| | - A J Copas
- Institute for Global Health, University College London, Mortimer Market Centre
| | - D M Lee
- Faculty of Health, Psychology and Social Care, Manchester Metropolitan University
| | - K R Mitchell
- MRC/CSO Social and Public Health Sciences Unit, University of Glasgow
| | - C H Mercer
- Institute for Global Health, University College London, Mortimer Market Centre
| | - P Sonnenberg
- Institute for Global Health, University College London, Mortimer Market Centre
| | - A M Johnson
- Institute for Global Health, University College London, Mortimer Market Centre
| | - K Wellings
- Department of Public Health, Environments and Society, Faculty of Public Health and Policy, London School of Hygiene & Tropical Medicine
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6
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Abstract
Gene drives have already challenged governance systems. In this case study, we explore the International Genetically Engineered Machine (iGEM) competition's experiences in gene drive-related research and lessons in developing, revising, and implementing a governance system. iGEM's experiences and lessons are distilled into 6 key insights for future gene drive policy development in the United States: (1) gene drives deserve special attention because of their potential for widescale impact and remaining uncertainty about how to evaluate intergenerational and transboundary risks; (2) an adaptive risk management approach is logical for gene drives because of the rapidly changing technical environment; (3) review by individual technical experts is limited and may fail to incorporate other forms of expertise and, therefore, must be complemented with a range of alternative governance methods; (4) current laboratory biosafety and biosecurity review processes may not capture gene drive research or its components in practice even if they are covered theoretically; (5) risk management for research and development must incorporate discussions of values and broader implications of the work; and (6) a regular technology horizon scanning capacity is needed for the early identification of advances that could pose governance system challenges.
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Affiliation(s)
- Piers Millett
- Piers Millett, PhD, is Vice President for Safety and Security, iGEM Foundation, Cambridge, MA
| | - Tessa Alexanian
- Tessa Alexanian is a Safety and Security Program Officer and iGEM Foundation, Cambridge, MA
| | - Megan J Palmer
- Megan J. Palmer, PhD, is a Bio Policy and Leadership Initiatives and Adjunct Professor, Department of Bioengineering, Stanford University, Stanford, CA
| | - Sam Weiss Evans
- Sam Weiss Evans, DPhil, is a Senior Research Fellow, Program on Science, Technology, and Society, Harvard University, Cambridge, MA
| | - Todd Kuiken
- Todd Kuiken, PhD, is a Senior Research Scholar, Genetic Engineering and Society Center, North Carolina State University, Raleigh, NC
| | - Kenneth Oye
- Kenneth Oye, PhD, is a Professor of Political Science and Director of the Program on Emerging Technologies, Massachusetts Institute of Technology, Cambridge, MA
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7
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Abstract
The COVID-19 pandemic has demonstrated the world's vulnerability to biological catastrophe and elicited unprecedented scientific efforts. Some of this work and its derivatives, however, present dual-use risks (i.e., potential harm from misapplication of beneficial research) that have largely gone unaddressed. For instance, gain-of-function studies and reverse genetics protocols may facilitate the engineering of concerning SARS-CoV-2 variants and other pathogens. The risk of accidental or deliberate release of dangerous pathogens may be increased by large-scale collection and characterization of zoonotic viruses undertaken in an effort to understand what enables animal-to-human transmission. These concerns are exacerbated by the rise of preprint publishing that circumvents a late-stage opportunity for dual-use oversight. To prevent the next global health emergency, we must avoid inadvertently increasing the threat of future biological events. This requires a nuanced and proactive approach to dual-use evaluation throughout the research life cycle, including the conception, funding, conduct, and dissemination of research.
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Affiliation(s)
| | - Jonas B. Sandbrink
- Future of Humanity Institute, University of Oxford, Oxford, United Kingdom
- Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Joshua Teperowski Monrad
- Future of Humanity Institute, University of Oxford, Oxford, United Kingdom
- Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Health Policy, London School of Economics, London, United Kingdom
| | - Megan J. Palmer
- Department of Bioengineering, Stanford University, Stanford, California, USA
- Center for International Security and Cooperation (CISAC), Stanford University, Stanford, California, USA
| | - Gregory D. Koblentz
- Schar School of Policy and Government, George Mason University, Fairfax, Virginia, USA
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8
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Mackelprang R, Aurand ER, Bovenberg RAL, Brink KR, Charo RA, Delborne JA, Diggans J, Ellington AD, Fortman JL“C, Isaacs FJ, Medford JI, Murray RM, Noireaux V, Palmer MJ, Zoloth L, Friedman DC. Guiding Ethical Principles in Engineering Biology Research. ACS Synth Biol 2021; 10:907-910. [PMID: 33977723 DOI: 10.1021/acssynbio.1c00129] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Engineering biology is being applied toward solving or mitigating some of the greatest challenges facing society. As with many other rapidly advancing technologies, the development of these powerful tools must be considered in the context of ethical uses for personal, societal, and/or environmental advancement. Researchers have a responsibility to consider the diverse outcomes that may result from the knowledge and innovation they contribute to the field. Together, we developed a Statement of Ethics in Engineering Biology Research to guide researchers as they incorporate the consideration of long-term ethical implications of their work into every phase of the research lifecycle. Herein, we present and contextualize this Statement of Ethics and its six guiding principles. Our goal is to facilitate ongoing reflection and collaboration among technical researchers, social scientists, policy makers, and other stakeholders to support best outcomes in engineering biology innovation and development.
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Affiliation(s)
- Rebecca Mackelprang
- Engineering Biology Research Consortium, Emeryville, California 94608, United States
| | - Emily R. Aurand
- Engineering Biology Research Consortium, Emeryville, California 94608, United States
| | - Roel A. L. Bovenberg
- Synthetic Biology and Cell Engineering, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, The Netherlands
- DSM Biotechnology Centre, Delft, 2613AX, The Netherlands
| | - Kathryn R. Brink
- PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, Texas 77005, United States
| | - R. Alta Charo
- The University of Wisconsin Law School, Madison, Wisconsin 53706, United States
| | - Jason A. Delborne
- Genetic Engineering and Society Center, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - James Diggans
- Twist Bioscience, South San Francisco, California 94080, United States
| | - Andrew D. Ellington
- Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, Texas 78712, United States
| | | | - Farren J. Isaacs
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520, United States
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut 06511, United States
- Systems Biology Institute, Yale University, West Haven, Connecticut 06516, United States
| | - June I. Medford
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Richard M. Murray
- Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Vincent Noireaux
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Megan J. Palmer
- Department of Bioengineering, Stanford University, Stanford, California 94040, United States
| | - Laurie Zoloth
- University of Chicago, Chicago, Illinois 60637, United States
| | - Douglas C. Friedman
- Engineering Biology Research Consortium, Emeryville, California 94608, United States
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9
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Burgiel SW, Baumgartner B, Brister E, Fisher J, Gordon DR, Novak B, Palmer MJ, Seddon PJ, Weber M. Exploring the intersections of governance, constituencies, and risk in genetic interventions. Conservat Sci and Prac 2021. [DOI: 10.1111/csp2.380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
| | | | - Evelyn Brister
- Philosophy Department Rochester Institute of Technology Rochester New York USA
| | - Joshua Fisher
- U.S. Fish and Wildlife Service†, Pacific Islands Fish and Wildlife Office Honolulu Hawaii USA
| | - Doria R. Gordon
- Environmental Defense Fund Washington District of Columbia USA
| | - Ben Novak
- Revive & Restore Sausalito California USA
| | - Megan J. Palmer
- Department of Bioengineering Stanford University Stanford California USA
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10
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Phelan R, Baumgartner B, Brand S, Brister E, Burgiel SW, Charo RA, Coche I, Cofrancesco A, Delborne JA, Edwards O, Fisher JP, Gaywood M, Gordon DR, Howald G, Hunter ME, Kareiva P, Mankad A, Marvier M, Moseby K, Newhouse AE, Novak BJ, Ohrstrom G, Olson S, Palmer MJ, Palumbi S, Patterson N, Pedrono M, Pelegri F, Rohwer Y, Ryder OA, Saah JR, Scheller RM, Seddon PJ, Shaffer HB, Shapiro B, Sweeney M, Tercek MR, Thizy D, Tilt W, Weber M, Wegrzyn RD, Whitelaw B, Winkler M, Wodak J, Zimring M, Robbins P. Intended consequences statement. Conservat Sci and Prac 2021. [DOI: 10.1111/csp2.371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
| | | | | | - Evelyn Brister
- Rochester Institute of Technology Rochester New York USA
| | | | - R. Alta Charo
- University of Wisconsin‐Madison Madison Wisconsin USA
| | | | - Al Cofrancesco
- U.S. Army Corps of Engineers, Engineer Research and Development Center Vicksburg Mississippi USA
| | - Jason A. Delborne
- Genetic Engineering and Society Center North Carolina State University Raleigh North Carolina USA
| | - Owain Edwards
- Commonwealth Scientific and Industrial Research Organisation Floreat Western Australia Australia
| | | | | | - Doria R. Gordon
- Environmental Defense Fund Washington District of Columbia USA
| | - Gregg Howald
- Advanced Conservation Strategies Williamsburg Virginia USA
| | - Margaret E. Hunter
- U.S. Geological Survey, Wetland and Aquatic Research Center Gainesville Florida USA
| | | | - Aditi Mankad
- Commonwealth Scientific and Industrial Research Organisation Floreat Western Australia Australia
| | - Michelle Marvier
- Department of Environmental Studies and Sciences Santa Clara University Santa Clara California USA
| | | | - Andrew E. Newhouse
- State University of New York, College of Environmental Science and Forestry Syracuse New York USA
| | | | | | - Steven Olson
- Association of Zoos and Aquariums Silver Spring Maryland USA
| | | | - Stephen Palumbi
- Hopkins Marine Station Stanford University Pacific Grove California USA
| | - Neil Patterson
- State University of New York College of Environmental Science and Forestry Center for Native Peoples & the Environment Syracuse New York USA
| | - Miguel Pedrono
- French Agricultural Research Centre for International Development (CIRAD, UMR ASTRE) Montpellier France
| | - Francisco Pelegri
- Laboratory of Genetics University of Wisconsin‐Madison Madison Wisconsin USA
| | - Yasha Rohwer
- Oregon Institute of Technology Klamath Falls Oregon USA
| | | | | | - Robert M. Scheller
- Department of Forestry and Environmental Resources North Carolina State University Raleigh North Carolina USA
| | | | - H. Bradley Shaffer
- Department of Ecology and Evolutionary Biology and La Kretz Center for California Conservation Science, Institute of the Environment and Sustainability University of California Los Angeles California USA
| | - Beth Shapiro
- Department of Ecology and Evolutionary Biology, and the Howard Hughes Medical Institute University of California Santa Cruz California USA
| | - Mike Sweeney
- The Nature Conservancy San Francisco California USA
| | | | | | | | | | | | - Bruce Whitelaw
- The Roslin Institute University of Edinburgh Midlothian UK
| | | | - Josh Wodak
- Institute for Culture and Society, Western Sydney University Parramatta New South Wales Australia
| | - Mark Zimring
- The Nature Conservancy San Francisco California USA
| | - Paul Robbins
- Nelson Institute for Environmental Studies University of Wisconsin‐Madison Madison Wisconsin USA
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11
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Abstract
Global health security is constantly under threat from infectious diseases. Despite advances in biotechnology that have improved diagnosis and treatment of such diseases, delays in detecting outbreaks and the lack of countermeasures for some biological agents continue to pose severe challenges to global health security. In this review, we describe some of the challenges facing global health security and how genome editing technologies can help overcome them. We provide specific examples of how the genome-editing tool CRISPR is being used to develop new tools to characterize pathogenic agents, diagnose infectious disease, and develop vaccines and therapeutics to mitigate the effects of an outbreak. The article also discusses some of the challenges associated with genome-editing technologies and the efforts that scientists are undertaking to mitigate them. Overall, CRISPR and genome-editing technologies are poised to have a significant positive influence on global health security over the years to come.
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Affiliation(s)
- Kyle E Watters
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA
| | - Jesse Kirkpatrick
- Institute for Philosophy and Public Policy, George Mason University, Fairfax, VA, USA
| | - Megan J Palmer
- Department of Bioengineering, Stanford University, Stanford, CA, USAs
| | - Gregory D Koblentz
- Schar School of Policy and Government, George Mason University, Fairfax, VA, USA
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12
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Affiliation(s)
- Evelyn Brister
- Philosophy Department Rochester Institute of Technology Rochester New York USA
| | - J. Britt Holbrook
- Department of Humanities New Jersey Institute of Technology Newark New Jersey USA
| | - Megan J. Palmer
- Department of Bioengineering Stanford University Stanford California USA
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13
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Long KC, Alphey L, Annas GJ, Bloss CS, Campbell KJ, Champer J, Chen CH, Choudhary A, Church GM, Collins JP, Cooper KL, Delborne JA, Edwards OR, Emerson CI, Esvelt K, Evans SW, Friedman RM, Gantz VM, Gould F, Hartley S, Heitman E, Hemingway J, Kanuka H, Kuzma J, Lavery JV, Lee Y, Lorenzen M, Lunshof JE, Marshall JM, Messer PW, Montell C, Oye KA, Palmer MJ, Papathanos PA, Paradkar PN, Piaggio AJ, Rasgon JL, Rašić G, Rudenko L, Saah JR, Scott MJ, Sutton JT, Vorsino AE, Akbari OS. Core commitments for field trials of gene drive organisms. Science 2020; 370:1417-1419. [DOI: 10.1126/science.abd1908] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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14
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Kemp L, Adam L, Boehm CR, Breitling R, Casagrande R, Dando M, Djikeng A, Evans NG, Hammond R, Hills K, Holt LA, Kuiken T, Markotić A, Millett P, Napier JA, Nelson C, ÓhÉigeartaigh SS, Osbourn A, Palmer MJ, Patron NJ, Perello E, Piyawattanametha W, Restrepo-Schild V, Rios-Rojas C, Rhodes C, Roessing A, Scott D, Shapira P, Simuntala C, Smith RDJ, Sundaram LS, Takano E, Uttmark G, Wintle BC, Zahra NB, Sutherland WJ. Bioengineering horizon scan 2020. eLife 2020; 9:e54489. [PMID: 32479263 PMCID: PMC7259952 DOI: 10.7554/elife.54489] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 05/14/2020] [Indexed: 01/01/2023] Open
Abstract
Horizon scanning is intended to identify the opportunities and threats associated with technological, regulatory and social change. In 2017 some of the present authors conducted a horizon scan for bioengineering (Wintle et al., 2017). Here we report the results of a new horizon scan that is based on inputs from a larger and more international group of 38 participants. The final list of 20 issues includes topics spanning from the political (the regulation of genomic data, increased philanthropic funding and malicious uses of neurochemicals) to the environmental (crops for changing climates and agricultural gene drives). The early identification of such issues is relevant to researchers, policy-makers and the wider public.
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Affiliation(s)
- Luke Kemp
- Centre for the Study of Existential Risk (CSER), University of CambridgeCambridgeUnited Kingdom
- Biosecurity Research Initiative at St Catharine’s College, University of CambridgeCambridgeUnited Kingdom
| | | | - Christian R Boehm
- Centre for the Study of Existential Risk (CSER), University of CambridgeCambridgeUnited Kingdom
| | - Rainer Breitling
- Manchester Institute of Biotechnology, Faculty of Science and Bioengineering, University of ManchesterManchesterUnited Kingdom
| | | | - Malcolm Dando
- Division of Peace Studies and International Development, University of BradfordBradfordUnited Kingdom
| | - Appolinaire Djikeng
- Centre for Tropical Livestock Genetics and Health, Royal (Dick) School of Veterinary StudiesEdinburghUnited Kingdom
| | - Nicholas G Evans
- Department of Philosophy, University of MassachusettsLowellUnited States
- Rogue BioethicsLowellUnited States
| | | | | | - Lauren A Holt
- Centre for the Study of Existential Risk (CSER), University of CambridgeCambridgeUnited Kingdom
- Biosecurity Research Initiative at St Catharine’s College, University of CambridgeCambridgeUnited Kingdom
| | - Todd Kuiken
- Genetic Engineering and Society Center, North Carolina State UniversityRaleighUnited States
| | - Alemka Markotić
- University Hospital for Infectious DiseasesZagrebCroatia
- Medical School, University of RijekaRijekaCroatia
- Catholic University of CroatiaZagrebCroatia
| | - Piers Millett
- Future of Humanity Institute, University of OxfordOxfordUnited Kingdom
- iGem FoundationBostonUnited States
| | | | - Cassidy Nelson
- Future of Humanity Institute, University of OxfordOxfordUnited Kingdom
| | - Seán S ÓhÉigeartaigh
- Centre for the Study of Existential Risk (CSER), University of CambridgeCambridgeUnited Kingdom
- Biosecurity Research Initiative at St Catharine’s College, University of CambridgeCambridgeUnited Kingdom
| | | | - Megan J Palmer
- Center for International Security and Cooperation (CSIAC), Stanford UniversityStanfordUnited States
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | | | | | - Wibool Piyawattanametha
- Biomedical Engineering Department, Faculty of Engineering, King Mongkut's Institute of Technology LadkrabangBangkokThailand
- Institute for Quantitative Health Sciences and Engineering, Michigan State UniversityEast LansingUnited States
| | | | - Clarissa Rios-Rojas
- Centre for the Study of Existential Risk (CSER), University of CambridgeCambridgeUnited Kingdom
- Ekpa’Palek: Empowering Latin-American Young ProfessionalsLimaPeru
| | - Catherine Rhodes
- Centre for the Study of Existential Risk (CSER), University of CambridgeCambridgeUnited Kingdom
- Biosecurity Research Initiative at St Catharine’s College, University of CambridgeCambridgeUnited Kingdom
| | - Anna Roessing
- Department of Politics, Languages and International Studies, University of BathBathUnited Kingdom
| | - Deborah Scott
- Science, Technology & Innovation Studies, School of Social and Political Science, University of EdinburghEdinburghUnited Kingdom
| | - Philip Shapira
- Manchester Institute of Innovation Research, Alliance Manchester Business School, University of ManchesterManchesterUnited Kingdom
- SYNBIOCHEM, University of ManchesterManchesterUnited Kingdom
- School of Public Policy, Georgia Institute of TechnologyAtlantaUnited States
| | | | - Robert DJ Smith
- Science, Technology & Innovation Studies, School of Social and Political Science, University of EdinburghEdinburghUnited Kingdom
| | - Lalitha S Sundaram
- Centre for the Study of Existential Risk (CSER), University of CambridgeCambridgeUnited Kingdom
- Biosecurity Research Initiative at St Catharine’s College, University of CambridgeCambridgeUnited Kingdom
| | - Eriko Takano
- Manchester Institute of Biotechnology, Faculty of Science and Bioengineering, University of ManchesterManchesterUnited Kingdom
| | - Gwyn Uttmark
- Department of Chemistry, Stanford UniversityStanfordUnited States
| | - Bonnie C Wintle
- School of BioSciences, University of MelbourneMelbourneAustralia
| | - Nadia B Zahra
- Department of Biotechnology, Qarshi UniversityLahorePakistan
| | - William J Sutherland
- Biosecurity Research Initiative at St Catharine’s College, University of CambridgeCambridgeUnited Kingdom
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
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15
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Evans SW, Beal J, Berger K, Bleijs DA, Cagnetti A, Ceroni F, Epstein GL, Garcia-Reyero N, Gillum DR, Harkess G, Hillson NJ, Hogervorst PAM, Jordan JL, Lacroix G, Moritz R, ÓhÉigeartaigh SS, Palmer MJ, van Passel MWJ. Embrace experimentation in biosecurity governance. Science 2020; 368:138-140. [PMID: 32273459 DOI: 10.1126/science.aba2932] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Sam Weiss Evans
- Program on Science, Technology, and Society, Harvard University, Cambridge, MA, USA. .,Program on Emerging Technology, Massachusetts Institute of Technology, Cambridge, MA, USA.,Centre for the Study of Existential Risk, University of Cambridge, Cambridge, UK
| | - Jacob Beal
- Raytheon BBN Technologies, Cambridge, MA, USA
| | | | - Diederik A Bleijs
- Netherlands Biosecurity Office, National Institute for Public Health and the Environment, Bilthoven, Netherlands
| | - Alessia Cagnetti
- Polo d'Innovazione Genomica Genetica e Biologia (PoloGGB), Terni, Italy
| | - Francesca Ceroni
- Department of Chemical Engineering, Imperial College London, London, UK.,Imperial College Centre for Synthetic Biology, London, UK
| | - Gerald L Epstein
- Center for the Study of Weapons of Mass Destruction, National Defense University, Washington, DC, USA
| | | | | | | | - Nathan J Hillson
- Joint Genome Institute, U.S. Department of Energy, Berkeley, CA, USA
| | - Petra A M Hogervorst
- Netherlands Biosecurity Office, National Institute for Public Health and the Environment, Bilthoven, Netherlands
| | | | - Geneviève Lacroix
- Centre for Biosecurity, Public Health Agency of Canada, Ottawa, Canada
| | | | - Seán S ÓhÉigeartaigh
- Centre for the Study of Existential Risk, University of Cambridge, Cambridge, UK
| | - Megan J Palmer
- Center for International Security and Cooperation, Stanford University, Stanford, CA, USA
| | - Mark W J van Passel
- Netherlands Biosecurity Office, National Institute for Public Health and the Environment, Bilthoven, Netherlands
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16
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17
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Sample M, Boulicault M, Allen C, Bashir R, Hyun I, Levis M, Lowenthal C, Mertz D, Montserrat N, Palmer MJ, Saha K, Zartman J. Multi-cellular engineered living systems: building a community around responsible research on emergence. Biofabrication 2019; 11:043001. [PMID: 31158828 PMCID: PMC7551891 DOI: 10.1088/1758-5090/ab268c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ranging from miniaturized biological robots to organoids, multi-cellular engineered living systems (M-CELS) pose complex ethical and societal challenges. Some of these challenges, such as how to best distribute risks and benefits, are likely to arise in the development of any new technology. Other challenges arise specifically because of the particular characteristics of M-CELS. For example, as an engineered living system becomes increasingly complex, it may provoke societal debate about its moral considerability, perhaps necessitating protection from harm or recognition of positive moral and legal rights, particularly if derived from cells of human origin. The use of emergence-based principles in M-CELS development may also create unique challenges, making the technology difficult to fully control or predict in the laboratory as well as in applied medical or environmental settings. In response to these challenges, we argue that the M-CELS community has an obligation to systematically address the ethical and societal aspects of research and to seek input from and accountability to a broad range of stakeholders and publics. As a newly developing field, M-CELS has a significant opportunity to integrate ethically responsible norms and standards into its research and development practices from the start. With the aim of seizing this opportunity, we identify two general kinds of salient ethical issues arising from M-CELS research, and then present a set of commitments to and strategies for addressing these issues. If adopted, these commitments and strategies would help define M-CELS as not only an innovative field, but also as a model for responsible research and engineering.
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Affiliation(s)
- Matthew Sample
- Pragmatic Health Ethics Research Unit, Institut de recherches cliniques de Montreal and Department of Neurology and Neurosurgery, McGill University, Canada
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18
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Millett P, Binz T, Evans SW, Kuiken T, Oye K, Palmer MJ, van der Vlugt C, Yambao K, Yu S. Developing a Comprehensive, Adaptive, and International Biosafety and Biosecurity Program for Advanced Biotechnology: The iGEM Experience. Appl Biosaf 2019; 24:64-71. [PMID: 36033940 PMCID: PMC9387731 DOI: 10.1177/1535676019838075] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/17/2023]
Abstract
INTRODUCTION The international synthetic biology competition iGEM (formally known as the international Genetically Engineered Machines competition) has a dedicated biosafety and biosecurity program. METHOD A review of specific elements of the program and a series of concrete examples illustrate how experiences in implementing the program have helped improved policy, including an increasing diversity of sources for genetic parts and organisms, keeping pace with technical developments, considering pathways toward future environmental release, addressing antimicrobial resistance, and testing the efficacy of current biosecurity arrangements. RESULTS iGEM's program is forward-leaning, in that it addresses both traditional (pathogen-based) and emerging risks both in terms of new technologies and new risks. It is integrated into the technical work of the competition-with clearly described roles and responsibilities for all members of the community. It operates throughout the life cycle of projects-from project design to future application. It makes use of specific tools to gather and review biosafety and biosecurity information, making it easier for those planning and conducting science and engineering to recognize potential risks and match them with appropriate risk management approaches, as well as for specialists to review this information to identify gaps and strengthen plans. DISCUSSION Integrating an increasingly adaptive risk management approach has allowed iGEM's biosafety and biosecurity program to become comprehensive, be cross-cutting, and cover the competition's life cycle.
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Affiliation(s)
| | - Thomas Binz
- Swiss Federal Office of Public Health, Berne, Switzerland
| | - Sam Weiss Evans
- Program in Science, Technology, and Society, Tufts University, Medford, MA, USA
| | - Todd Kuiken
- Genetic Engineering and Society Center, North Carolina State University, Raleigh, NC, USA
| | - Ken Oye
- MIT Program on Emerging Technologies, Cambridge, MA, USA
| | - Megan J. Palmer
- Center for International Security and Cooperation, Stanford University, Stanford, CA, USA
| | - Cécile van der Vlugt
- Dutch National Institute for Public Health and the Environment, Bilthoven, Netherlands
| | | | - Samuel Yu
- Health Safety and Environment Office, Hong Kong University of Science and Technology, Hong Kong
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Abstract
Governance is a broader and more flexible concept than statute-driven regulations as it incorporates components outside the latter's remit. Considerations of governance are critical in the development of emerging biotechnologies such as gene drive organisms. These have been proposed or are being developed to address public and environmental health issues not addressed easily by conventional means. Here, we consider how the concept of governance differs from statute-driven regulation with reference to the role each may play in the development of gene drive organisms. First, we discuss existing statute-based regulatory systems. Second, we consider whether novel risks or different concerns derive from gene drive organisms, concentrating on characteristics that contribute to public health or environmental risk and uncertainties that may affect risk perceptions. Third, we consider public engagement, outlining how existing statute-driven regulatory systems and other governance mechanisms may provide opportunities for constructive interactions. Finally, we provide some observations that may help address science- and values-based concerns in a governance space larger than that of statute-driven regulatory systems.
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Affiliation(s)
- Larisa Rudenko
- Visiting Scholar, Program on Emerging Technologies, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Megan J. Palmer
- Center for International Security and Cooperation, Stanford University, Stanford, CA, USA
| | - Kenneth Oye
- Program on Emerging Technologies, Massachusetts Institute of Technology, Cambridge, MA, USA
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21
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Datta J, Palmer MJ, Tanton C, Gibson LJ, Jones KG, Macdowall W, Glasier A, Sonnenberg P, Field N, Mercer CH, Johnson AM, Wellings K. Prevalence of infertility and help seeking among 15 000 women and men. Hum Reprod 2016; 31:2108-18. [PMID: 27365525 PMCID: PMC4991655 DOI: 10.1093/humrep/dew123] [Citation(s) in RCA: 221] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 04/29/2016] [Indexed: 12/03/2022] Open
Abstract
STUDY QUESTION What is the prevalence of infertility and of help seeking among women and men in Britain? SUMMARY ANSWER One in eight women and one in ten men aged 16–74 years had experienced infertility, defined by unsuccessfully attempting pregnancy for a year or longer, and little more than half of these people sought medical or professional help. WHAT IS KNOWN ALREADY Estimates of infertility and help seeking in Britain vary widely and are not easily comparable because of different definitions and study populations. STUDY DESIGN, SIZE, DURATION A cross-sectional population survey was conducted between 2010 and 2012 with a sample of 15 162 women and men aged 16–74 years. PARTICIPANTS/MATERIALS, SETTING, METHODS Participants completed the Natsal-3 questionnaire, using computer-assisted personal interviewing (CAPI) and computer-assisted self-interview (CASI). MAIN RESULTS AND THE ROLE OF CHANCE The reported prevalence of infertility was 12.5% (CI 95% 11.7–13.3) among women and 10.1% (CI 95% 9.2–11.1) among men. Increased prevalence was associated with later cohabitation with a partner, higher socio-economic status and, for those who had a child, becoming parents at older ages. The reported prevalence of help seeking was 57.3% (CI 95% 53.6–61.0) among women and 53.2% (CI 95% 48.1–58.1) among men. Help seekers were more likely to be better educated and in higher status occupations and, among those who had a child, to have become parents later in life. LIMITATIONS, REASONS FOR CAUTION These data are cross-sectional so it is not possible to establish temporality or infer causality. Self-reported data may be subject to recall bias. WIDER IMPLICATIONS OF THE FINDINGS The study provides estimates of infertility and help seeking in Britain and the results indicate that the prevalence of infertility is higher among those delaying parenthood. Those with higher educational qualifications and occupational status are more likely to consult with medical professionals for fertility problems than others and these inequalities in help seeking should be considered by clinical practice and public health. STUDY FUNDING/COMPETING INTEREST(S) Funding was provided by grants from the Medical Research Council and the Wellcome Trust, with support from the Economic and Social Research Council and the Department of Health. AMJ is a Governor of the Wellcome Trust. Other authors have no competing interests.
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Affiliation(s)
- J Datta
- Centre for Sexual and Reproductive Health Research, Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
| | - M J Palmer
- Centre for Sexual and Reproductive Health Research, Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
| | - C Tanton
- Research Department of Infection and Population Health, University College London, Mortimer Market Centre, London WC1E 6JB, UK
| | - L J Gibson
- Centre for Sexual and Reproductive Health Research, Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
| | - K G Jones
- Research Department of Infection and Population Health, University College London, Mortimer Market Centre, London WC1E 6JB, UK
| | - W Macdowall
- Centre for Sexual and Reproductive Health Research, Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
| | - A Glasier
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TY, UK Centre for Sexual and Reproductive Health Research, Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
| | - P Sonnenberg
- Research Department of Infection and Population Health, University College London, Mortimer Market Centre, London WC1E 6JB, UK
| | - N Field
- Research Department of Infection and Population Health, University College London, Mortimer Market Centre, London WC1E 6JB, UK
| | - C H Mercer
- Research Department of Infection and Population Health, University College London, Mortimer Market Centre, London WC1E 6JB, UK
| | - A M Johnson
- Research Department of Infection and Population Health, University College London, Mortimer Market Centre, London WC1E 6JB, UK
| | - K Wellings
- Centre for Sexual and Reproductive Health Research, Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
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22
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Korosi JB, Eickmeyer DC, Chin KS, Palmer MJ, Kimpe LE, Blais JM. Examining spatial patterns in polycyclic aromatic compounds measured in stream macroinvertebrates near a small subarctic oil and gas operation. Environ Monit Assess 2016; 188:189. [PMID: 26911593 DOI: 10.1007/s10661-016-5175-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 02/10/2016] [Indexed: 06/05/2023]
Abstract
The Cameron River runs through a small, remote petrochemical development in the Cameron Hills (Northwest Territories, Canada). In order to evaluate the exposure of aquatic biota to contaminants from oil and gas activities, we measured polycyclic aromatic compounds (PACs) in macroinvertebrates collected from sites and tributaries along the Cameron River, including upstream and downstream of the development, and sites located near drilled wells (developed). Macroinvertebrate tissue PAC burdens ranged from 0.2-2.8 μg g(-1) lipid for unsubstituted compounds, and from 4.2-63.2 μg g(-1) lipid for alkylated compounds, relatively low compared to similar studies from more industrialized regions in North America. There was no significant difference in tissue PAC burdens between upstream, downstream, or developed sites (p = 0.12), although alkyl PACs in five out of seven developed sites were higher than the regional average. Petrogenic PACs were dominant in most samples, including alkyl fluorines, alkyl phenanthrene/anthracenes, and alkyl dibenzothiophenes. Minimal changes in PAC composition in macroinvertebrate tissues were detected along the Cameron River, with the exception of the two sites furthest downstream that had high concentrations of C3-C4 naphthalene. Overall, our results suggest that oil and gas development in the Cameron Hills has not resulted in substantial increases in PAC bioaccumulation in stream macroinvertebrates, although the potential that alkyl naphthalenes are being transported downstream from the development warrants further attention.
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Affiliation(s)
- J B Korosi
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, K1N 6N5, Canada.
| | - D C Eickmeyer
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, K1N 6N5, Canada
| | - K S Chin
- Cumulative Impact Monitoring Program, Environment and Natural Resources, Government of the Northwest Territories, 5102 50th Avenue, Yellowknife, NT, X1A 3S8, Canada
| | - M J Palmer
- Cumulative Impact Monitoring Program, Environment and Natural Resources, Government of the Northwest Territories, 5102 50th Avenue, Yellowknife, NT, X1A 3S8, Canada
| | - L E Kimpe
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, K1N 6N5, Canada
| | - J M Blais
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, K1N 6N5, Canada
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23
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Palmer MJ, Clarke L, Wellings K. OP45 ‘Sexual competence’ at first heterosexual intercourse: examining the prevalence and correlates of a context-based measure of first intercourse in a population-based sample of british 16–24 year olds. Br J Soc Med 2015. [DOI: 10.1136/jech-2015-206256.44] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
Synthetic biology seeks to make engineering of complex biological functions more efficient, reliable, and predictable. Advancing the process of engineering biology requires community organization and leadership. As synthetic biology matures into a globally significant enterprise, the community needs to enable a next generation of leaders to organize the field's responsible advancement. We discuss key points raised at a community meeting on these issues at SB6.0--the Sixth International Meeting on Synthetic Biology--and highlight opportunities to carry forward the conversation.
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Affiliation(s)
- Megan J. Palmer
- California
Institute for Quantitative Biosciences (QB3); Synthetic Biology Engineering
Research Center (Synberc), University of California Berkeley, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Michael C. Jewett
- Department
of Chemical and Biological Engineering; Chemistry of Life Processes
Institute; Institute for Bionanotechnology in Medicine, Member, Robert
H. Lurie Comprehensive Cancer Center Northwestern University, 2145 Sheridan
Road, Evanston, Illinois 60208, United States
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25
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Wright GA, Baker DD, Palmer MJ, Stabler D, Mustard JA, Power EF, Borland AM, Stevenson PC. Caffeine in floral nectar enhances a pollinator's memory of reward. Science 2013; 339:1202-4. [PMID: 23471406 DOI: 10.1126/science.1228806] [Citation(s) in RCA: 191] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Plant defense compounds occur in floral nectar, but their ecological role is not well understood. We provide evidence that plant compounds pharmacologically alter pollinator behavior by enhancing their memory of reward. Honeybees rewarded with caffeine, which occurs naturally in nectar of Coffea and Citrus species, were three times as likely to remember a learned floral scent as were honeybees rewarded with sucrose alone. Caffeine potentiated responses of mushroom body neurons involved in olfactory learning and memory by acting as an adenosine receptor antagonist. Caffeine concentrations in nectar did not exceed the bees' bitter taste threshold, implying that pollinators impose selection for nectar that is pharmacologically active but not repellent. By using a drug to enhance memories of reward, plants secure pollinator fidelity and improve reproductive success.
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Affiliation(s)
- G A Wright
- Centre for Behaviour and Evolution, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE1 7RU, UK.
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26
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Abstract
Plant defense compounds occur in floral nectar, but their ecological role is not well understood. We provide evidence that plant compounds pharmacologically alter pollinator behavior by enhancing their memory of reward. Honeybees rewarded with caffeine, which occurs naturally in nectar of Coffea and Citrus species, were three times as likely to remember a learned floral scent as were honeybees rewarded with sucrose alone. Caffeine potentiated responses of mushroom body neurons involved in olfactory learning and memory by acting as an adenosine receptor antagonist. Caffeine concentrations in nectar did not exceed the bees' bitter taste threshold, implying that pollinators impose selection for nectar that is pharmacologically active but not repellent. By using a drug to enhance memories of reward, plants secure pollinator fidelity and improve reproductive success.
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Affiliation(s)
- G A Wright
- Centre for Behaviour and Evolution, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE1 7RU, UK.
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27
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Jones SM, Palmer MJ. Activation of the tonic GABAC receptor current in retinal bipolar cell terminals by nonvesicular GABA release. J Neurophysiol 2009; 102:691-9. [PMID: 19494193 DOI: 10.1152/jn.00285.2009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Within the second synaptic layer of the retina, bipolar cell (BC) output to ganglion cells is regulated by inhibitory input to BC axon terminals. GABA(A) receptors (GABA(A)Rs) mediate rapid synaptic currents in BC terminals, whereas GABA(C) receptors (GABA(C)Rs) mediate slow evoked currents and a tonic current, which is strongly regulated by GAT-1 GABA transporters. We have used voltage-clamp recordings from BC terminals in goldfish retinal slices to determine the source of GABA for activation of these currents. Inhibition of vesicular release with concanamycin A or tetanus toxin significantly inhibited GABA(A)R inhibitory postsynaptic currents and glutamate-evoked GABA(A)R and GABA(C)R currents but did not reduce the tonic GABA(C)R current, which was also not dependent on extracellular Ca(2+). The tonic current was strongly potentiated by inhibition of GABA transaminase, under both normal and Ca(2+)-free conditions, and was activated by exogenous taurine; however inhibition of taurine transport had little effect. The tonic current was unaffected by GAT-2/3 inhibition and was potentiated by GAT-1 inhibition even in the absence of vesicular release, indicating that it is unlikely to be evoked by reversal of GABA transporters or by ambient GABA. In addition, GABA release does not appear to occur via hemichannels or P2X(7) receptors. BC terminals therefore exhibit two forms of GABA(C)R-mediated inhibition, activated by vesicular and by nonvesicular GABA release, which are likely to have distinct functions in visual signal processing. The tonic GABA(C)R current in BC terminals exhibits similar properties to tonic GABA(A)R and glutamate receptor currents in the brain.
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Affiliation(s)
- S M Jones
- Neuroscience Group, Institute for Science and Technology in Medicine, Keele University, Keele, Staffordshire ST5 5BG, United Kingdom
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28
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Moy B, Tu D, Shepherd LE, Palmer MJ, Ingle JN, Goss PE. NCIC CTG MA.17: hormone receptor expression of in-breast recurrences and contralateral primary breast cancers arising on aromatase inhibitors. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-1134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #1134
Background: The selective estrogen receptor modulators (SERMs) tamoxifen and raloxifene reduce the risk of ER+ (but not ER-) invasive breast cancers in healthy women at high risk for developing breast cancer. Aromatase inhibitors (AIs) given as adjuvant therapy to treatment-naïve or post-tamoxifen patients significantly reduce the risk of in-breast recurrences (IBRs) and contralateral breast cancers (CBCs) and are currently in clinical trials for breast cancer prevention (NCIC CTG MAP.3 and IBIS-II). It is hypothesized that SERMS inhibit promotion of ER+ breast cancer whereas AIs may reduce both ER+ and ER- breast cancer by inhibiting both tumor initiation and promotion. Little is known about the characteristics of IBRs and CBCs that arise on AI therapy. We present the ER/PR expression and clinicopathologic features of IBRs and CBCs that occurred on MA.17.
 Methods: We examined ER/PR status of IBRs and CBCs that arose on letrozole vs. placebo among women enrolled in MA.17, a placebo-controlled (PLAC) trial of letrozole (LET) following 5 years of tamoxifen in postmenopausal women with early stage breast cancer.
 Results: Seventy-one patients (pts) developed an IBR and 87 developed a CBC on trial. Consistent with results previously reported, fewer IBRs (LET 20 vs PLAC 51) and CBCs (LET 35 vs PLAC 52) were observed in the LET group. ER and PR status is currently available on 35 women with an IBR and 39 with a CBC. The majority of IBRs were ER+ in both the LET and PLAC groups (10/11 [91%] vs 18/24 [75%], respectively; p=NS) but numbers of both ER+ and – IBRs were less in LET group, suggesting that letrozole may decrease both ER+ and ER- IBRs. CBCs that arose on PLAC were more likely to be ER+ than on LET (16/22 [73%] vs 6/19 pts [32%], respectively; p=0.01), suggesting that letrozole predominantly prevents ER+ CBCs. Discordance in ER expression between primary breast cancer and IBRs among women randomized to LET vs. PLAC was observed in 1/11 [9%] and 6/24 [26%] women respectively (p=NS) and between primary breast cancer and CBCs in 12/18 pts [67%] vs. 6/21 [29%] women respectively (p=0.01). Other clinicopathologic characteristics such as grade, tumor size, PR, HER-2/neu, and nodal status of IBRs and CBCs will be presented at the meeting.
 Conclusion: Extended adjuvant endocrine therapy with letrozole results in fewer IBRs and CBCs compared with placebo as previously reported. Our data suggests that letrozole may decrease both ER+ and ER- IBRs. Letrozole appears to prevent ER+ CBCs but has little or no apparent effect on the development of ER- CBCs. These results need confirmation in the primary prevention trials of AIs.
 

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1134.
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Affiliation(s)
- B Moy
- 1 Massachusetts General Hospital, Boston, MA
| | - D Tu
- 2 National Cancer Institute of Canada Clinical Trials Group, Kingston, ON, Canada
| | - LE Shepherd
- 2 National Cancer Institute of Canada Clinical Trials Group, Kingston, ON, Canada
| | - MJ Palmer
- 2 National Cancer Institute of Canada Clinical Trials Group, Kingston, ON, Canada
| | | | - PE Goss
- 1 Massachusetts General Hospital, Boston, MA
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Palmer MJ, Mahajan VS, Trajman LC, Irvine DJ, Lauffenburger DA, Chen J. Interleukin-7 receptor signaling network: an integrated systems perspective. Cell Mol Immunol 2008; 5:79-89. [PMID: 18445337 DOI: 10.1038/cmi.2008.10] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Interleukin-7 (IL-7) is an essential cytokine for the development and homeostatic maintenance of T and B lymphocytes. Binding of IL-7 to its cognate receptor, the IL-7 receptor (IL-7R), activates multiple pathways that regulate lymphocyte survival, glucose uptake, proliferation and differentiation. There has been much interest in understanding how IL-7 receptor signaling is modulated at multiple interconnected network levels. This review examines how the strength of the signal through the IL-7 receptor is modulated in T and B cells, including the use of shared receptor components, signaling crosstalk, shared interaction domains, feedback loops, integrated gene regulation, multimerization and ligand competition. We discuss how these network control mechanisms could integrate to govern the properties of IL-7R signaling in lymphocytes in health and disease. Analysis of IL-7 receptor signaling at a network level in a systematic manner will allow for a comprehensive approach to understanding the impact of multiple signaling pathways on lymphocyte biology.
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Affiliation(s)
- Megan J Palmer
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Ingle JN, Tu D, Pater JL, Muss HB, Martino S, Robert NJ, Piccart MJ, Castiglione M, Shepherd LE, Pritchard KI, Livingston RB, Davidson NE, Norton L, Perez EA, Abrams JS, Cameron DA, Palmer MJ, Goss PE. Intent-to-treat analysis of the placebo-controlled trial of letrozole for extended adjuvant therapy in early breast cancer: NCIC CTG MA.17. Ann Oncol 2008; 19:877-82. [PMID: 18332043 DOI: 10.1093/annonc/mdm566] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND MA.17 evaluated letrozole or placebo after 5 years of tamoxifen and showed significant improvement in disease-free survival (DFS) for letrozole [hazard ratio (HR) 0.57, P = 0.00008]. The trial was unblinded and placebo patients were offered letrozole. PATIENTS AND METHODS An intent-to-treat analysis of all outcomes, before and after unblinding, on the basis of the original randomization was carried out. RESULTS In all, 5187 patients were randomly allocated to the study at baseline and, at unblinding, 1579 (66%) of 2383 placebo patients accepted letrozole. At median follow-up of 64 months (range 16-95), 399 recurrences or contralateral breast cancers (CLBCs) (164 letrozole and 235 placebo) occurred. Four-year DFS was 94.3% (letrozole) and 91.4% (placebo) [HR 0.68, 95% confidence interval (CI) 0.55-0.83, P = 0.0001] and showed superiority for letrozole in both node-positive and -negative patients. Corresponding 4-year distant DFS was 96.3% and 94.9% (HR 0.80, 95% CI 0.62-1.03, P = 0.082). Four-year overall survival was 95.1% for both groups. The annual rate of CLBC was 0.28% for letrozole and 0.46% for placebo patients (HR 0.61, 95% CI 0.39-0.97, P = 0.033). CONCLUSIONS Patients originally randomly assigned to receive letrozole within 3 months of stopping tamoxifen did better than placebo patients in DFS and CLBC, despite 66% of placebo patients taking letrozole after unblinding.
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Affiliation(s)
- J N Ingle
- Division of Medical Oncology, Mayo Clinic, Rochester, MN 55905, USA.
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Findlay B, Tonkin K, Crump M, Norris B, Trudeau M, Blackstein M, Burnell M, Skillings J, Bowman D, Walde D, Levine M, Pritchard KI, Palmer MJ, Tu D, Shepherd L. A dose escalation trial of adjuvant cyclophosphamide and epirubicin in combination with 5-fluorouracil using G-CSF support for premenopausal women with breast cancer involving four or more positive nodes. Ann Oncol 2007; 18:1646-51. [PMID: 17716984 DOI: 10.1093/annonc/mdm277] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Dose-dense and dose-intensive regimens have improved the outcome of breast cancer in high-risk women with operable disease. PATIENTS AND METHODS Sixty-three premenopausal women with Stage 2, 3 breast cancer and > or =4 positive axillary nodes were treated in three successive cohorts with 70 mg/m(2) of epirubicin, 500 mg/m(2) of 5-fluorouracil and G-CSF every 14 days for 12 cycles. Cyclophosphamide (C) was given at 700 mg/m(2), 900 mg/m(2), and 1100 mg/m(2) doses. Patients were evaluated for dose-limiting toxicities (DLTs) in the first four cycles, the primary endpoint of the trial. RESULTS No DLTs were seen at C 700 mg/m(2); at C 900 mg/m(2) two of 16 patients experienced febrile neutropenia and poor performance status; at C 1100 mg/m(2), 1 of 31 patients experienced poor performance status. Over 6 months, febrile neutropenia, grade 4 thrombocytopenia, grade 3 anemia and severe fatigue were observed. Clinical congestive heart failure occurred in three patients over 4 years. CONCLUSION A dose-intense and dose-dense regimen of cyclophosphamide, epirubicin and 5-fluorouracil was delivered with G-CSF without apparent increase in acute toxicity. Cyclophosphamide could be increased to more than twice the standard dose at the cost of more anemia and fatigue.
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Affiliation(s)
- B Findlay
- Hotel Dieu Hospital, St Catharines, Ontario, Canada.
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Palmer MJ, Dekock PC, Bacon JS. Changes in the concentrations of malic acid, citric acid, calcium and potassium in the leaves during the growth of normal and iron-deficient mustard plants (Sinapis alba). Biochem J 2006; 86:484-94. [PMID: 16748991 PMCID: PMC1201783 DOI: 10.1042/bj0860484] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- M J Palmer
- Departments of Biochemistry and Plant Physiology, Macaulay Institute for Soil Research, Aberdeen
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Wasan KM, Goss PE, Pritchard PH, Shepherd L, Palmer MJ, Liu S, Tu D, Ingle JN, Heath M, Deangelis D, Perez EA. The influence of letrozole on serum lipid concentrations in postmenopausal women with primary breast cancer who have completed 5 years of adjuvant tamoxifen (NCIC CTG MA.17L). Ann Oncol 2005; 16:707-15. [PMID: 15817595 DOI: 10.1093/annonc/mdi158] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The purpose of this study was to evaluate changes in serum lipid parameters {cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides and lipoprotein(a) [Lp(a)]}, in postmenopausal women receiving letrozole or placebo after adjuvant tamoxifen for early stage breast cancer (NCIC CTG MA.17L). PATIENTS AND METHODS MA.17L is a substudy of MA.17, a randomized, double-blind, placebo-controlled trial of letrozole 2.5 mg taken daily for 5 years in postmenopausal women with primary breast cancer completing approximately 5 years of prior adjuvant tamoxifen. Patients consenting to participate in this companion study had blood drawn and lipid parameters (total cholesterol, HDL cholesterol, LDL cholesterol, Lp(a), triglycerides) evaluated at baseline, 6 months, 12 months and yearly thereafter until completion of protocol therapy. It was required that women be non-hyperlipidemic and not taking lipid-lowering drugs at time of entry on this trial. RESULTS Three hundred and forty seven women were enrolled in the study. The letrozole and the placebo groups demonstrated marginally significant differences in the percentage change from baseline in HDL cholesterol at 6 months (P=0.049), in LDL cholesterol at 12 months (P=0.033) and triglycerides at 24 months (P=0.036). All comparisons of lipid parameters at other time points were not significantly different between the two treatment groups. No statistically significant differences in the number of patients exceeding the thresholds defined for the lipid parameters were found between the two treatment groups. CONCLUSIONS The MA.17 trial demonstrated a significant improvement in disease-free survival with the use of letrozole as extended adjuvant therapy post tamoxifen. Results from this study suggests that letrozole does not significantly alter serum cholesterol, HDL cholesterol, LDL cholesterol, triglycerides or Lp(a) in non-hyperlidiemic postmenopausal women with primary breast cancer treated up to 36 months following at least 5 years of adjuvant tamoxifen therapy. These findings further support the tolerability of extended adjuvant letrozole in postmenopausal women following standard tamoxifen therapy.
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Affiliation(s)
- K M Wasan
- Division of Pharmaceutics and Biopharmaceutics, Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, BC, Canada.
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Fitzjohn SM, Palmer MJ, May JE, Neeson A, Morris SA, Collingridge GL. A characterisation of long-term depression induced by metabotropic glutamate receptor activation in the rat hippocampus in vitro. J Physiol 2001; 537:421-30. [PMID: 11731575 PMCID: PMC2278956 DOI: 10.1111/j.1469-7793.2001.00421.x] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 06/14/2001] [Accepted: 08/13/2001] [Indexed: 11/27/2022] Open
Abstract
1. In the CA1 region of hippocampal slices prepared from juvenile (12- to 18-day-old) rats, activation of group I metabotropic L-glutamate (mGlu) receptors by the specific agonist (RS)-3,5-dihydroxyphenylglycine (DHPG) induces a form of long-term depression (LTD) of excitatory synaptic transmission. 2. We have used a variety of electrophysiological techniques applied to CA1 neurones in hippocampal slices and from pyramidal cells in dissociated hippocampal cultures to investigate the Ca2+ dependence and locus of expression of DHPG-induced LTD. 3. In patch-clamp experiments from hippocampal slices, bath application of DHPG induced a depression of synaptically evoked responses that persisted for the duration of the recording (up to 2 h after commencing washout of DHPG) in 27 of 29 neurones investigated. 4. DHPG-induced LTD was associated with an increase in both the paired-pulse facilitation ratio and the coefficient of variation of EPSCs. 5. Using dendritic recording, there was a decrease in EPSC success rate (number of trials that elicited a detectable response) but no change in potency (mean EPSC amplitude excluding failures) associated with DHPG-induced LTD. 6. In experiments using dissociated hippocampal cultures, application of DHPG elicited a persistent decrease in the frequency of tetrodotoxin-resistant miniature EPSCs but no change in the amplitude of such events. 7. DHPG-induced LTD was not blocked by intracellular application of the calcium chelator BAPTA. It was also unaffected when intracellular calcium stores were depleted by perfusion with thapsigargin. Furthermore, when synaptic transmission was blocked by perfusing with Ca2+-free medium, DHPG application reliably induced LTD. 8. These data suggest that DHPG-induced LTD is Ca2+ independent and is expressed presynaptically.
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Affiliation(s)
- S M Fitzjohn
- MRC Centre for Synaptic Plasticity, Department of Anatomy, University of Bristol, University Walk, Bristol BS8 1TD, UK.
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Benke TA, Lüthi A, Palmer MJ, Wikström MA, Anderson WW, Isaac JT, Collingridge GL. Mathematical modelling of non-stationary fluctuation analysis for studying channel properties of synaptic AMPA receptors. J Physiol 2001; 537:407-20. [PMID: 11731574 PMCID: PMC2278972 DOI: 10.1111/j.1469-7793.2001.00407.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
1. The molecular properties of synaptic alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors are an important factor determining excitatory synaptic transmission in the brain. Changes in the number (N) or single-channel conductance (gamma) of functional AMPA receptors may underlie synaptic plasticity, such as long-term potentiation (LTP) and long-term depression (LTD). These parameters have been estimated using non-stationary fluctuation analysis (NSFA). 2. The validity of NSFA for studying the channel properties of synaptic AMPA receptors was assessed using a cable model with dendritic spines and a microscopic kinetic description of AMPA receptors. Electrotonic, geometric and kinetic parameters were altered in order to determine their effects on estimates of the underlying gamma. 3. Estimates of gamma were very sensitive to the access resistance of the recording (R(A)) and the mean open time of AMPA channels. Estimates of gamma were less sensitive to the distance between the electrode and the synaptic site, the electrotonic properties of dendritic structures, recording electrode capacitance and background noise. Estimates of gamma were insensitive to changes in spine morphology, synaptic glutamate concentration and the peak open probability (P(o)) of AMPA receptors. 4. The results obtained using the model agree with biological data, obtained from 91 dendritic recordings from rat CA1 pyramidal cells. A correlation analysis showed that R(A) resulted in a slowing of the decay time constant of excitatory postsynaptic currents (EPSCs) by approximately 150 %, from an estimated value of 3.1 ms. R(A) also greatly attenuated the absolute estimate of gamma by approximately 50-70 %. 5. When other parameters remain constant, the model demonstrates that NSFA of dendritic recordings can readily discriminate between changes in gamma vs. changes in N or P(o). Neither background noise nor asynchronous activation of multiple synapses prevented reliable discrimination between changes in gamma and changes in either N or P(o). 6. The model (available online) can be used to predict how changes in the different properties of AMPA receptors may influence synaptic transmission and plasticity.
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Affiliation(s)
- T A Benke
- MRC Centre for Synaptic Plasticity, Department of Anatomy, University of Bristol, University Walk, Bristol BS8 1TD, UK.
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Ipe NE, Rosser KE, Moretti CJ, Manning JW, Palmer MJ. Air kerma calibration factors and chamber correction values for PTW soft x-ray, NACP and Roos ionization chambers at very low x-ray energies. Phys Med Biol 2001; 46:2107-17. [PMID: 11512614 DOI: 10.1088/0031-9155/46/8/306] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This paper evaluates the characteristics of ionization chambers for the measurement of absorbed dose to water using very low-energy x-rays. The values of the chamber correction factor, k(ch), used in the IPEMB 1996 code of practice for the UK secondary standard ionization chambers (PTW type M23342 and PTW type M23344), the Roos (PTW type 34001) and NACP electron chambers are derived. The responses in air of the small and large soft x-ray chambers (PTW type M23342 and PTW type M23344) and the NACP and Roos electron ionization chambers were compared. Besides the soft x-ray chambers, the NACP and Roos chambers can be used for very low-energy x-ray dosimetry provided that they are used in the restricted energy range for which their response does not change by more than 5%. The chamber correction factor was found by comparing the absorbed dose to water determined using the dosimetry protocol recommended for low-energy x-rays with that for very low-energy x-rays. The overlap energy range was extended using data from Grosswendt and Knight. Chamber correction factors given in this paper are chamber dependent, varying from 1.037 to 1.066 for a PTW type M23344 chamber, which is very different from a value of unity given in the IPEMB code. However, the values of k(ch) determined in this paper agree with those given in the DIN standard within experimental uncertainty. The authors recommend that the very low-energy section of the IPEMB code is amended to include the most up-to-date values of k(ch).
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Affiliation(s)
- N E Ipe
- Radiation Physics Department, Stanford Linear Accelerator Center, CA 94305, USA
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Doherty AJ, Palmer MJ, Bortolotto ZA, Hargreaves A, Kingston AE, Ornstein PL, Schoepp DD, Lodge D, Collingridge GL. A novel, competitive mGlu(5) receptor antagonist (LY344545) blocks DHPG-induced potentiation of NMDA responses but not the induction of LTP in rat hippocampal slices. Br J Pharmacol 2000; 131:239-44. [PMID: 10991916 PMCID: PMC1572327 DOI: 10.1038/sj.bjp.0703574] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2000] [Revised: 06/29/2000] [Accepted: 06/30/2000] [Indexed: 11/08/2022] Open
Abstract
1. We have investigated the pharmacological properties of LY344545, a structurally related epimer of the broad spectrum competitive metabotropic glutamate receptor antagonist, LY341495. We have found that LY344545 also antagonizes competitively nearly all mGlu receptor subtypes, but with a wide spectrum of activity. The order of potency for the human receptor isoforms was mGlu(5a) (IC(50) of 5. 5+/-0.6 microM)>mGlu(2)=mGlu(3)>mGlu(1alpha)=mG lu(7)>mGlu(6)=mGlu(8). No significant mGlu(4) receptor antagonist activity was detected at the highest concentration used (100 microM). 100 microM LY344545 displaced 50+/-5% of [(3)H]-CGP39653 binding, but less than 30% of [(3)H]-kainate or [(3)H]-AMPA in radioligand binding assays. 2. LY344545 antagonized L-glutamate stimulated Ca(2+) release in CHO cells transfected with mGlu receptors in a concentration dependent manner with a 10 fold higher affinity for the rat mGlu(5a) receptor (K:(i)=2.1+/-0.6 microM) compared to the rat mGlu(1alpha) receptor (K:(i)=20.5+/-2.1 microM). 50 microM (1S, 3R)-ACPD-induced Ca(2+) rises in hippocampal CA1 neurones were also antagonized (IC(50)=6. 8+/-0.7 microM). 3. LY344545 antagonized 10 microM (S)-3,5-DHPG-induced potentiation of NMDA depolarizations in CA1 neurones (EC(50)=10. 6+/-1.0 microM). At higher concentrations (> or =100 microM), LY344545 was an NMDA receptor antagonist. 4. LY344545 also blocked the induction, but not the expression, of LTP at CA3 to CA1 synapses with an IC(50)>300 microM. This effect is consistent with its weak activity at NMDA receptors. 5. These results demonstrate that the binding of ligands to mGlu receptor subtypes is critically dependent on the spatial orientation of the same molecular substituents within a given chemical pharmacophore. The identification of LY344545 as the first competitive antagonist to show selectivity towards mGlu(5) receptors supports the potential to design more selective and potent competitive antagonists of this receptor. 6. These results further indicate that mGlu receptor-mediated potentiation of NMDA responses is not essential for the induction of LTP.
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Affiliation(s)
- A J Doherty
- MRC Centre for Synaptic Plasticity, Department of Anatomy, School of Medical Sciences, University of Bristol, University Walk, Bristol, BS8 1TD.
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Bergman DK, Palmer MJ, Caimano MJ, Radolf JD, Wikel SK. Isolation and molecular cloning of a secreted immunosuppressant protein from Dermacentor andersoni salivary gland. J Parasitol 2000; 86:516-25. [PMID: 10864249 DOI: 10.1645/0022-3395(2000)086[0516:iamcoa]2.0.co;2] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
A 36-kDa immunosuppressant protein (Da-p36) was isolated from salivary glands of feeding female ixodid ticks Dermacentor andersoni, using its affinity for UltraLink Biosupport Medium (Pierce, Rockford, Illinois)/protein complexes. Using a nested set of forward degenerate oligonucleotide primers corresponding to Da-p36 N-terminal amino acids, a cDNA encoding the immunosuppressant protein was isolated by 3' rapid amplification of cDNA ends. The resulting 772-base pair cDNA encodes a novel protein with predicted molecular weight of 24.9 kDa. Sequence analysis revealed the presence of 5 potential glycosylation sites and 1 myristylation site. Immunoblot analyses showed native Da-p36 is present in salivary glands and saliva from both male and female D. andersoni but not in salivary glands or saliva from Amblyomma americanum or Ixodes scapularis. Reverse transcription polymerase chain reaction and immunoblot analyses showed that Da-p36 expression is temporally regulated in salivary glands with maximum mRNA levels preceding maximum Da-p36 accumulation that occurred at day 6 of feeding. The levels of Da-p36 mRNA and protein were greatly reduced in salivary glands from near-replete females removed from sheep after 8 days of feeding. These data are consistent with a role of Da-p36 in immunosuppression during feeding.
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Affiliation(s)
- D K Bergman
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater 74078, USA
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Kirkbride P, Bezjak A, Pater J, Zee B, Palmer MJ, Wong R, Cross P, Gulavita S, Blood P, Sun A, Dundas G, Ganguly PK, Lim J, Chowdhury AD, Kumar SE, Dar AR. Dexamethasone for the prophylaxis of radiation-induced emesis: a National Cancer Institute of Canada Clinical Trials Group phase III study. J Clin Oncol 2000; 18:1960-6. [PMID: 10784638 DOI: 10.1200/jco.2000.18.9.1960] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE To investigate the efficacy of dexamethasone as a prophylactic antiemetic for patients receiving fractionated radiotherapy to the upper abdomen in a randomized controlled trial. PATIENTS AND METHODS One hundred fifty-four patients planned to receive fractionated radiotherapy to fields involving the upper abdomen (minimum total dose, 20 Gy; minimum number of fractions, five) were randomized to receive prophylactic dexamethasone (2 mg orally three times a day [tid], starting in the morning of first treatment and continuing until after their fifth treatment) or placebo. The primary end point of the study was the proportion of patients free from emesis during the study period. Secondary end points included a quality-of-life assessment using the core questionnaire of the European Organization for Research and Treatment of Cancer and side effects of dexamethasone therapy in this population of patients. RESULTS Fifty-four (70%) out of 75 patients receiving dexamethasone had complete protection versus 37 (49%) out of 75 patients on placebo (P = .025). Most emetic episodes occurred during the initial phase of treatment. Although there was no difference in global quality of life between the two sets of patients, patients receiving dexamethasone had less nausea and vomiting and less loss of appetite but more insomnia. CONCLUSION Dexamethasone 2 mg tid seems to be an effective prophylactic antiemetic in this situation. Side effects were acceptable, but there seemed to be no overall effect on global quality of life.
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Affiliation(s)
- P Kirkbride
- National Cancer Institute of Canada Clinical Trials Group, Kingston, Ontario, Canada.
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Lüthi A, Chittajallu R, Duprat F, Palmer MJ, Benke TA, Kidd FL, Henley JM, Isaac JT, Collingridge GL. Hippocampal LTD expression involves a pool of AMPARs regulated by the NSF-GluR2 interaction. Neuron 1999; 24:389-99. [PMID: 10571232 DOI: 10.1016/s0896-6273(00)80852-1] [Citation(s) in RCA: 239] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We investigated whether the interaction between the N-ethyl-maleimide-sensitive fusion protein (NSF) and the AMPA receptor (AMPAR) subunit GluR2 is involved in synaptic plasticity in the CA1 region of the hippocampus. Blockade of the NSF-GluR2 interaction by a specific peptide (pep2m) introduced into neurons prevented homosynaptic, de novo long-term depression (LTD). Moreover, saturation of LTD prevented the pep2m-induced reduction in AMPAR-mediated excitatory postsynaptic currents (EPSCs). Minimal stimulation experiments indicated that both pep2m action and LTD were due to changes in quantal size and quantal content but were not associated with changes in AMPAR single-channel conductance or EPSC kinetics. These results suggest that there is a pool of AMPARs dependent on the NSF-GluR2 interaction and that LTD expression involves the removal of these receptors from synapses.
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Affiliation(s)
- A Lüthi
- Medical Research Council Centre for Synaptic Plasticity, Department of Anatomy, University of Bristol, United Kingdom
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Abstract
We have shown previously that activation of mGlu receptors using a group I specific mGlu receptor agonist, (R,S)-3,5-dihydroxyphenylglycine (DHPG), can induce long-term depression (LTD) in the CA1 region of the hippocampus (Palmer et al., 1997). We now report that DHPG-induced LTD is facilitated by treatment with KN-62, an inhibitor of certain Ca2+/calmodulin-dependent protein kinases (CaMKs), including CaMKII.
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Affiliation(s)
- R Schnabel
- Department of Anatomy, School of Medical Sciences, University of Bristol, UK.
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Palmer MJ, McSwain JL, Spatz MD, Tucker JS, Essenberg RC, Sauer JR. Molecular cloning of cAMP-dependent protein kinase catalytic subunit isoforms from the lone star tick, Amblyomma americanum (L.). Insect Biochem Mol Biol 1999; 29:43-51. [PMID: 10070744 DOI: 10.1016/s0965-1748(98)00103-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The salivary glands of ixodid ticks are central to tick feeding and to survival during off-host periods. They produce and secrete a number of molecules critical to maintaining the complex host-vector interface and to maintaining osmotic balance. We have previously shown that a cyclic AMP-dependent protein kinase (cAPK) is involved in the mechanism of salivary gland secretion. We have now cloned cDNAs encoding three isoforms of the catalytic subunit (cAPK-C) of the cAPK from Amblyomma americanum, which are probably produced from alternative RNA processing of a single cAPK-C gene. The cDNAs contain unique N-termini of variable lengths that are linked to a common region containing the alpha A helix, catalytic core, and a C-terminal tail. The common region is highly similar to both insect and vertebrate cAPK-Cs. We have examined mRNA profiles in whole ticks and in isolated salivary glands throughout feeding and find that a single cAPK-C isoform is expressed in the salivary glands of both unfed and feeding females.
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Affiliation(s)
- M J Palmer
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater 74078-3033, USA
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Fitzjohn SM, Bortolotto ZA, Palmer MJ, Doherty AJ, Ornstein PL, Schoepp DD, Kingston AE, Lodge D, Collingridge GL. The potent mGlu receptor antagonist LY341495 identifies roles for both cloned and novel mGlu receptors in hippocampal synaptic plasticity. Neuropharmacology 1998; 37:1445-58. [PMID: 9886667 DOI: 10.1016/s0028-3908(98)00145-2] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Understanding the roles of metabotropic glutamate (mGlu) receptors has been severely hampered by the lack of potent antagonists. LY341495 (2S-2-amino-2-(1S,2S-2-carboxycyclopropyl-1-yl)-3-(xanth-9-y l)propanoic acid) has been shown to block group II mGlu receptors in low nanomolar concentrations (Kingston, A.E., Ornstein, P.L., Wright, R.A., Johnson, B.G., Mayne, N.G., Burnett, J.P., Belagaje, R., Wu, S., Schoepp, D.D., 1998. LY341495 is a nanomolar potent and selective antagonist at group II metabotropic glutamate receptors. Neuropharmacology 37, 1-12) but can be used in higher concentrations to block all hippocampal mGlu receptors, identified so far by molecular cloning (mGlu1-5,7,8). Here we have further characterised the mGlu receptor antagonist activity of LY341495 and have used this compound to investigate roles of mGlu receptors in hippocampal long-term potentiation (LTP) and long-term depression (LTD). LY341495 competitively antagonised DHPG-stimulated PI hydrolysis in AV12-664 cells expressing either human mGlu1 or mGlu5 receptors with Ki-values of 7.0 and 7.6 microM, respectively. When tested against 10 microM L-glutamate-stimulated Ca2+ mobilisation in rat mGlu5 expressing CHO cells, it produced substantial or complete block at a concentration of 100 microM. In rat hippocampal slices, LY341495 eliminated 30 microM DHPG-stimulated PI hydrolysis and 100 microM (1S,3R)-ACPD-inhibition of forskolin-stimulated cAMP formation at concentrations of 100 and 0.03 microM, respectively. In area CA1, it antagonised DHPG-mediated potentiation of NMDA-induced depolarisations and DHPG-induced long-lasting depression of AMPA receptor-mediated synaptic transmission. LY341495 also blocked NMDA receptor-independent depotentiation and setting of a molecular switch involved in the induction of LTP; effects which have previously been shown to be blocked by the mGlu receptor antagonist (S)-MCPG. These effects may therefore be due to activation of cloned mGlu receptors. In contrast, LY341495 did not affect NMDA receptor-dependent homosynaptic LTD; an effect which may therefore be independent of cloned mGlu receptors. Finally, LY341495 failed to antagonise NMDA receptor-dependent LTP and, in area CA3, NMDA receptor-independent, mossy fibre LTP. Since in the same inputs these forms of LTP were blocked by (S)-MCPG, a novel type of mGlu receptor may be involved in their induction.
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Affiliation(s)
- S M Fitzjohn
- Department of Anatomy, University of Bristol, UK.
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Isaac JT, Lüthi A, Palmer MJ, Anderson WW, Benke TA, Collingridge GL. An investigation of the expression mechanism of LTP of AMPA receptor-mediated synaptic transmission at hippocampal CA1 synapses using failures analysis and dendritic recordings. Neuropharmacology 1998; 37:1399-410. [PMID: 9849675 DOI: 10.1016/s0028-3908(98)00140-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
There is considerable controversy surrounding the mechanism of expression of long-term potentiation of AMPA receptor-mediated synaptic transmission in the CA1 region of the hippocampus, a process thought to be important for learning and memory in the mammalian CNS. We have re-examined the expression mechanism of this form of synaptic plasticity using whole-cell dendritic recordings, minimal stimulation to activate one or a few synapses, and failures analysis. Dendritic recordings provide improved resolution of small synaptic events, as compared to previous studies using somatic recordings, because there is less dendritic filtering of signals. We find that long-term potentiation (LTP) is associated with changes in the size of synaptic responses when they occur (potency) in all cells and this is accompanied by significant decreases in failure rate in approximately 60% of the experiments. This suggests that in some cells an increase in quantal amplitude is the sole expression mechanism for LTP and, in the cells where failure rate decreased, there is an additional mechanism causing a change in quantal content.
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Affiliation(s)
- J T Isaac
- Department of Anatomy, University of Bristol, UK
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Guo X, Xu Q, Harmon MA, Jin X, Laudet V, Mangelsdorf DJ, Palmer MJ. Isolation of two functional retinoid X receptor subtypes from the Ixodid tick, Amblyomma americanum (L.). Mol Cell Endocrinol 1998; 139:45-60. [PMID: 9705073 DOI: 10.1016/s0303-7207(98)00073-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Retinoid X receptors (RXR) play a central role in a variety of nuclear signaling pathways in both vertebrates and invertebrates. Vertebrate RXRs are encoded by a multigene family whereas the insect RXR homologue, ultraspiracle (USP), is encoded by a single gene. To determine if acarines possess an RXR homologue similar to insect USPs, we isolated cDNAs encoding two distinct RXR genes, AamRXR1 and AamRXR2, from the ixodid tick, Amblyomma americanum (L.). The DNA binding domains share 95 and 87% identity, respectively, with DNA binding domains from insect USP and vertebrate RXR proteins. However, the ligand binding domains of the AamRXRs are more similar to vertebrate RXRs than to insect USP ligand binding domains (approximately 71 vs approximately 52%). Northern blot and RT-PCR analysis reveal both unique and overlapping patterns of AamRXR1 and AamRXR2 expression. Transactivation analysis show that both AamRXRs encode proteins which can form functional ecdysteroid receptors but are unlikely to bind retinoic acids.
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Affiliation(s)
- X Guo
- Department of Entomology, Oklahoma State University, Stillwater 74078, USA
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Guo X, Harmon MA, Laudet V, Mangelsdorf DJ, Palmer MJ. Isolation of a functional ecdysteroid receptor homologue from the ixodid tick Amblyomma americanum (L.). Insect Biochem Mol Biol 1997; 27:945-962. [PMID: 9501418 DOI: 10.1016/s0965-1748(97)00075-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Ecdysteroids are assumed to be the major steroid hormones in arthropods. However, with the exception of insects and crustaceans, very little is known about ecdysteroid action in other arthropods. To determine if ecdysteriods play a functional role in the ixodid tick, Amblyomma americanum (L.), we isolated cDNAs encoding three presumed ecdysteroid receptor isoforms (AamEcRA1, AamEcRA2, and AamEcRA3) that have common DNA and ligand binding domains linked to distinct amino termini. The DNA and ligand binding domains share an average of 86 and 64% identity, respectively with DNA and ligand binding domains from insect EcR proteins. The amino termini are highly divergent and the AamEcRs lack the 'F' domain found in the insect EcRs. Analysis of AamEcR cDNAs show that processing of the AamEcR gene is complex, producing multiple transcripts with unique 5' and 3' termini as well as splicing variants with incomplete open reading frames. AamEcR mRNA profiles in whole animals and isolated tissues are consistent with complex regulation of AamEcR expression. We also examined the ability of AamEcRA1, when paired with an AamRXR, to activate transcription of an ecdysone response element containing reporter, and demonstrate that the AamEcR gene encodes a functional ecdysteroid receptor.
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Affiliation(s)
- X Guo
- Department of Entomology, Oklahoma State University Stillwater 74078, USA
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Palmer MJ, Irving AJ, Seabrook GR, Jane DE, Collingridge GL. The group I mGlu receptor agonist DHPG induces a novel form of LTD in the CA1 region of the hippocampus. Neuropharmacology 1997; 36:1517-32. [PMID: 9517422 DOI: 10.1016/s0028-3908(97)00181-0] [Citation(s) in RCA: 277] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The group I specific metabotropic glutamate (mGlu) receptor agonist (RS)-3,5-dihydroxyphenylglycine (DHPG) (100 microM, 10 min) induced long-term depression (LTD) of synaptic transmission in the CA1 region of adult rat hippocampal slices, measured using a grease-gap recording technique. In "normal" (1 mM Mg2+-containing) medium, LTD (measured 30 min after washout of DHPG) was small (13+/-3%), but LTD was enhanced if DHPG was applied when the tissue was made hyperexcitable, either by omitting Mg2+ from the perfusate (35+/-3%) or by adding the GABA(A) receptor antagonist picrotoxin (29+/-2%). The N-methyl-D-aspartate (NMDA) receptor antagonist AP5 (100 microM) substantially reduced the generation of DHPG-induced LTD in Mg2+-free medium, but had little effect on LTD induced in the presence of picrotoxin. In Mg2+-free medium, the threshold concentration of DHPG required to induce LTD was between 1 and 3 microM. Neither agonists specific for group II (100 nM DCG-IV or 1 microM LY354740) or group III (10 microM L-AP4) mGlu receptors or a combined group I and II agonist (30-100 microM (1S,3R)-ACPD) induced LTD. However, an agonist (1 mM CHPG) which activates mGlu5 but not mGlu1 receptors did induce LTD. Surprisingly, DHPG-induced LTD was reversed by mGlu receptor antagonists, applied hours after washout of DHPG. DHPG-induced LTD did not occlude with LTD induced by synaptic activation (1200 stimuli delivered at 2 Hz), in Mg2+-free medium. These data show that activation of group I mGlu receptors (probably mGlu5) can induce LTD and that this mGlu receptor-mediated LTD may, or may not, require activation of NMDA receptors, depending on the experimental conditions.
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Affiliation(s)
- M J Palmer
- Department of Anatomy, School of Medical Sciences, University of Bristol, UK.
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Abstract
We tested the hypothesis that nimodipine, a dihydropyridine reported to increase blood flow, block calcium and potassium channels, and reduce ischemic damage, would alleviate noise-induced hearing loss. Young C57B1/6J mice were exposed to wide-band noise (2 min, 120 dB SPL), with ABR thresholds (4-50 kHz) determined before noise exposure, and from 1 h to 2 weeks afterwards. One group (n = 7) received nimodipine (30 mg/kg/day) in daily peanut butter food supplements beginning 24 h before exposure; the other group (n = 6) received peanut butter alone. In the pretest nimodipine significantly increased the latency of Wave P1 of the ABR (mean difference: 0.16 ms; P < 0.02), showing that calcium blockade depressed sensorineural efficiency, but ABR thresholds were not affected. Noise exposure produced a severe threshold loss that partially recovered in the first week after exposure, and then suffered a slight but significant loss in the second week. These effects were seen equally in both groups: nimodipine did not reduce the severity of the immediate hearing loss following noise exposure, nor did it benefit recovery.
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Affiliation(s)
- J R Ison
- Department of Brain and Cognitive Sciences, University of Rochester, NY 14627, USA.
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Doherty AJ, Palmer MJ, Henley JM, Collingridge GL, Jane DE. (RS)-2-chloro-5-hydroxyphenylglycine (CHPG) activates mGlu5, but no mGlu1, receptors expressed in CHO cells and potentiates NMDA responses in the hippocampus. Neuropharmacology 1997; 36:265-7. [PMID: 9144665 DOI: 10.1016/s0028-3908(97)00001-4] [Citation(s) in RCA: 256] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A new phenylglycine derivative, (RS)-2-chloro-5-hydroxyphenylglycine (CHPG), has been synthesized and shown to selectively activate mGlu5a receptors, compared to mGlu1 alpha receptors, when expressed in CHO cells. This selective mGlu5 receptor agonist also potentiates NMDA-induced depolarizations in rat hippocampal slices. CHPG may be a useful tool for studying the role of mGlu5 receptors in the central nervous system.
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Affiliation(s)
- A J Doherty
- Department of Anatomy, School of Medical Sciences, University of Bristol, UK
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McSwain JL, Luo C, deSilva GA, Palmer MJ, Tucker JS, Sauer JR, Essenberg RC. Cloning and sequence of a gene for a homologue of the C subunit of the V-ATPase from the salivary gland of the tick Amblyomma americanum (L). Insect Mol Biol 1997; 6:67-76. [PMID: 9013257 DOI: 10.1046/j.1365-2583.1997.00158.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A 1084 base pair partial cDNA showing similarity to the C subunit of the vacuolar ATPase (V-ATPase) was isolated on a clone from a cDNA library made from salivary glands from 3-day-old feeding adult Amblyomma americanum (L.) female ticks. The 5' end was completed using primer extension and the two pieces joined to form a complete cDNA of 1373 bp. This mRNA is expressed in embryos and the salivary glands of unfed adults and adult females at all stages of feeding. Specific inhibitors of the V-ATPase decrease the rate of dopamine-stimulated secretion of isolated salivary glands, but not as much as ouabain, an inhibitor of the Na+, K+ ATPase, indicating that a V-ATPase may participate in the mechanism of salivary fluid secretion in A. americanum, but the volume of saliva secreted is more dependent on an active Na+, K+ ATPase.
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Affiliation(s)
- J L McSwain
- Department of Entomology, Oklahoma State University, Stillwater 74078, USA
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