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1. Dynamic overload capability of VSC HVDC interconnections for frequency support

Author

Martinez Sanz, I, Judge, P, Spallarossa, C, Chaudhuri, B, Green, T, Engineering & Physical Science Research Council (EPSRC), and Engineering & Physical Science Research Council (E

Subjects
Technology, Electrical & Electronic Engineering, Science & Technology, HVDC, Energy & Fuels, POWER, Engineering, Electrical & Electronic, 0906 Electrical and Electronic Engineering, Engineering, power system dynamics, Frequency control, VSC overload, SYSTEM, modular multilevel converters (MMC)
Abstract

In future power systems, reduced overall inertia caused by an increased dominance of asynchronous generation and interconnections would make frequency control particularly challenging. As the number and power rating of voltage source converter (VSC) HVDC systems increases, network service provision would be expected from such systems and to do so would require overload capacity to be included in the converter specifications. This paper studies the provision of frequency services from modular multilevel converter (MMC)-based VSC HVDC interconnections using temperature-constrained overload capability. Overload of the MMC-based HVDC system is achieved through controlled circulating currents, at the expense of higher losses, and subject to a control scheme that dynamically limits the overload available in order to keep the semiconductor junction temperatures within operational limits. Two frequency control schemes that use the obtained overload capacity to provide frequency response during emergency conditions are investigated. The controllers' performance is demonstrated in the context of the future Great Britain transmission grid through a reduced equivalent test system. Simulation results show that even modest temperature margins which allow overload of MMC-based HVDC systems for a few seconds are effective as a primary frequency reserve and also reduce the loss of infeed requirements of such interconnections.

Published
2017

2. Advances and unmet needs in genetic, basic and clinical science in Alport syndrome: Report from the 2015 International Workshop on Alport Syndrome

Author

Gross, O., Kashtan, C. E., Rheault, M. N., Flinter, F., Savige, J., Miner, J. H., Torra, R., Ars, E., Constantinou-Deltas, Constantinos D., Savva, Isavella, Perin, L., Renieri, A., Ariani, F., Mari, F., Baigent, C., Judge, P., Knebelman, B., Heidet, L., Lagas, S., Blatt, D., Ding, J., Zhang, Y., Gale, D. P., Prunotto, M., Xue, Y., Schachter, A. D., Morton, L. C. G., Blem, J., Huang, M., Liu, S., Vallee, S., Renault, D., Schifter, J., Skelding, J., Gear, S., Friede, T., Turner, A. N., Lennon, R., and Constantinou-Deltas, Constantinos D. [0000-0001-5549-9169]

Subjects
Chronic kidney disease, Hereditary kidney disease, Guidelines, Nephroprotection, Alport syndrome
Abstract

Alport syndrome (AS) is a genetic disease characterized by haematuric glomerulopathy variably associated with hearing loss and anterior lenticonus. It is caused by mutations in the COL4A3, COL4A4 or COL4A5 genes encoding the a3a4a5(IV) collagen heterotrimer. AS is rare, but it accounts for >1% of patients receiving renal replacement therapy. Angiotensin-converting enzyme inhibition slows, but does not stop, the progression to renal failure therefore, there is an urgent requirement to expand and intensify research towards discovering new therapeutic targets and new therapies. The 2015 International Workshop on Alport Syndrome targeted unmet needs in basic science, genetics and diagnosis, clinical research and current clinical care. In three intensive days, more than 100 international experts including physicians, geneticists, researchers from academia and industry, and patient representatives from all over the world participated in panel discussions and breakout groups. This report summarizes the most important priority areas including (i) understanding the crucial role of podocyte protection and regeneration, (ii) targeting mutations by new molecular techniques for new animal models and potential gene therapy, (iii) creating optimal interaction between nephrologists and geneticists for early diagnosis, (iv) establishing standards for mutation screening and databases, (v) improving widespread accessibility to current standards of clinical care, (vi) improving collaboration with the pharmaceutical/biotech industry to investigate new therapies, (vii) research in hearing loss as a huge unmet need in Alport patients and (viii) the need to evaluate the risk and benefit of novel (including 'repurposing') therapies on an international basis. © The Author 2016. 32 916 924 Cited By :1

Published
2017

3. Engineering monolayer poration for rapid exfoliation of microbial membranes

Author

Pyne, A, Pfeil, M, Bennett, I, Yin, D, Muñoz-García, J, Judge, P, Grovenor, C, and Watts, A

Abstract

The spread of bacterial resistance to traditional antibiotics continues to stimulate the search for alternative antimicrobial strategies. All forms of life, from bacteria to humans, are postulated to rely on a fundamental host defense mechanism, which exploits the formation of open pores in microbial phospholipid bilayers. Here we predict that transmembrane poration is not necessary for antimicrobial activity and reveal a distinct poration mechanism that targets the outer leaflet of phospholipid bilayers. Using a combination of molecular-scale and real-time imaging, spectroscopy and spectrometry approaches, we introduce a structural motif with a universal insertion mode in reconstituted membranes and live bacteria. We demonstrate that this motif rapidly assembles into monolayer pits that coalesce during progressive membrane exfoliation, leading to bacterial cell death within minutes. The findings offer a new physical basis for designing effective antibiotics.

Published
2016

6. Historical eclipses and the recent solar minimum corona

Author

Judge, P. G., Burkepile, J., de Toma, G., and Druckmueller, M.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

We have studied the corona as seen at the eclipses of 1878, 1900, 1901 and others. These eclipses occurred during extended sunspot minimum conditions. We compare these data with those of the recent solar minimum corona, using data from the eclipses of July 22 2009 and August 1 2008. An attempt to characterize the global solar magnetic fields is made. We speculate on the origin of the non-dipolar structure seen in the 2008 and 2009 eclipse images., Comment: To appear in Proceedings of SOHO-23: Understanding a Peculiar Solar Minimum, Edited by Steven Cranmer, Todd Hoeksema, and John Kohl

Published
2010
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8. Activity Cycles of Southern Asteroseismic Targets

Author

Travis Metcalfe, Judge, P. G., Basu, S., Henry, T. J., Soderblom, D. R., Knoelker, M., and Rempel, M.

Subjects
Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

The Mount Wilson Ca HK survey revealed magnetic activity variations in a large sample of solar-type stars with timescales ranging from 2.5 to 25 years. This broad range of cycle periods is thought to reflect differences in the rotational properties and the depths of the surface convection zones for stars with various masses and ages. Asteroseismic data will soon provide direct measurements of these quantities for individual stars, but many of the most promising targets are in the southern sky (e.g., alpha Cen A & B, beta Hyi, mu Ara, tau Cet, nu Ind), while long-term magnetic activity cycle surveys are largely confined to the north. In 2007 we began using the SMARTS 1.5-m telescope to conduct a long-term monitoring campaign of Ca II H & K emission for a sample of 57 southern solar-type stars to measure their magnetic activity cycles and their rotational properties when possible. This sample includes the most likely southern asteroseismic targets to be observed by the Stellar Oscillations Network Group (SONG), currently scheduled to begin operations in 2012. We present selected results from the first two years of the survey, and from the longer time baseline sampled by a single-epoch survey conducted in 1992., proceedings of the "Solar Analogs II" workshop

10. Second asymptomatic carotid surgery trial (ACST-2): a randomised comparison of carotid artery stenting versus carotid endarterectomy

Author

Alison Halliday, Richard Bulbulia, Leo H Bonati, Johanna Chester, Andrea Cradduck-Bamford, Richard Peto, Hongchao Pan, John Potter, Hans Henning Eckstein, Barbara Farrell, Marcus Flather, Averil Mansfield, Boby Mihaylova, Kazim Rahimi, David Simpson, Dafydd Thomas, Peter Sandercock, Richard Gray, Andrew Molyneux, Cliff P Shearman, Peter Rothwell, Anna Belli, Will Herrington, Parminder Judge, Peter Leopold, Marion Mafham, Michael Gough, Piergiorgio Cao, Sumaira MacDonald, Vasha Bari, Clive Berry, S Bradshaw, Wojciech Brudlo, Alison Clarke, Robin Cox, Susan Fathers, Kamran Gaba, Mo Gray, Elizabeth Hayter, Constance Holliday, Rijo Kurien, Michael Lay, Steffi le Conte, Jessica McManus, Zahra Madgwick, Dylan Morris, Andrew Munday, Sandra Pickworth, Wiktor Ostasz, Michiel Poorthuis, Sue Richards, Louisa Teixeira, Sergey Tochlin, Lynda Tully, Carol Wallis, Monique Willet, Alan Young, Renato Casana, Chiara Malloggi, Andrea Odero Jr, Vincenzo Silani, Gianfranco Parati, Giuseppe Malchiodi, Giovanni Malferrari, Francesco Strozzi, Nicola Tusini, Enrico Vecchiati, Gioacchino Coppi, Antonio Lauricella, Roberto Moratto, Roberto Silingardi, Jessica Veronesi, Andrea Zini, Emanuele Ferrero, Michelangelo Ferri, Andrea Gaggiano, Carmelo Labate, Franco Nessi, Daniele Psacharopulo, Andrea Viazzo, Giovanni Malacrida, Daniela Mazzaccaro, Giovanni Meola, Alfredo Modafferi, Giovanni Nano, Maria Teresa Occhiuto, Paolo Righini, Silvia Stegher, Stefano Chiarandini, Filippo Griselli, Sandro Lepidi, Fabio Pozzi Mucelli, Marcello Naccarato, Mario D'Oria, Barbara Ziani, Andrea Stella, Mortalla Dieng, Gianluca Faggioli, Mauro Gargiulo, Sergio Palermo, Rodolfo Pini, Giovanni Maria Puddu, Andrea Vacirca, Domenico Angiletta, Claudio Desantis, Davide Marinazzo, Giovanni Mastrangelo, Guido Regina, Raffaele Pulli, Paolo Bianchi, Lea Cireni, Elisabetta Coppi, Rocco Pizzirusso, Filippo Scalise, Giovanni Sorropago, Valerio Tolva, Valeria Caso, Enrico Cieri, Paola DeRango, Luca Farchioni, Giacomo Isernia, Massimo Lenti, Gian Battista Parlani, Guglielmo Pupo, Grazia Pula, Gioele Simonte, Fabio Verzini, Federico Carimati, Maria Luisa Delodovici, Federico Fontana, Gabriele Piffaretti, Matteo Tozzi, Efrem Civilini, Giorgio Poletto, Bernhard Reimers, Barbara Praquin, Sonia Ronchey, Laura Capoccia, Wassim Mansour, Enrico Sbarigia, Francesco Speziale, Pasqualino Sirignano, Danilo Toni, Roberto Galeotti, Vincenzo Gasbarro, Francesco Mascoli, Tiberio Rocca, Elpiniki Tsolaki, Giulia Bernardini, Ester DeMarco, Alessia Giaquinta, Francesco Patti, Massimiliano Veroux, Pierfrancesco Veroux, Carla Virgilio, Nicola Mangialardi, Matteo Orrico, Vincenzo Di Lazzaro, Nunzio Montelione, Francesco Spinelli, Francesco Stilo, Carlo Cernetti, Sandro Irsara, Giuseppe Maccarrone, Diego Tonello, Adriana Visonà, Beniamino Zalunardo, Emiliano Chisci, Stefano Michelagnoli, Nicola Troisi, Maela Masato, Massimo Dei Negri, Andrea Pacchioni, Salvatore Saccà, Giovanni Amatucci, Alfredo Cannizzaro, Federico Accrocca, Cesare Ambrogi, Renzo Barbazza, Giustino Marcucci, Andrea Siani, Guido Bajardi, Giovanni Savettieri, Angelo Argentieri, Riccardo Corbetta, Attilio Odero, Pietro Quaretti, Federico Z Thyrion, Alessandro Cappelli, Domenico Benevento, Gianmarco De Donato, Maria Agnese Mele, Giancarlo Palasciano, Daniela Pieragalli, Alessandro Rossi, Carlo Setacci, Francesco Setacci, Domenico Palombo, Maria Cecilia Perfumo, Edoardo Martelli, Aldo Paolucci, Santi Trimarchi, Viviana Grassi, Luigi Grimaldi, Giuliana La Rosa, Domenico Mirabella, Matteo Scialabba, Leonildo Sichel, Costantino L D'Angelo, Gian Franco Fadda, Holta Kasemi, Mario Marino, Francesco Burzotta, Francesco Alberto Codispoti, Angela Ferrante, Giovanni Tinelli, Yamume Tshomba, Claudio Vincenzoni, Deborah Amis, Dawn Anderson, Martin Catterson, Mike Clarke, Michelle Davis, Anand Dixit, Alexander Dyker, Gary Ford, Ralph Jackson, Sreevalsan Kappadath, David Lambert, Tim Lees, Stephen Louw, James McCaslin, Noala Parr, Rebecca Robson, Gerard Stansby, Lucy Wales, Vera Wealleans, Lesley Wilson, Michael Wyatt, Hardeep Baht, Ibrahim Balogun, Ilse Burger, Tracy Cosier, Linda Cowie, Gunaratnam Gunathilagan, David Hargroves, Robert Insall, Sally Jones, Hannah Rudenko, Natasha Schumacher, Jawaharlal Senaratne, George Thomas, Audrey Thomson, Tom Webb, Ellen Brown, Bernard Esisi, Ali Mehrzad, Shane MacSweeney, Norman McConachie, Alison Southam, Wayne Sunman, Ahmed Abdul-Hamiq, Jenny Bryce, Ian Chetter, Duncan Ettles, Raghuram Lakshminarayan, Kim Mitchelson, Christopher Rhymes, Graham Robinson, Paul Scott, Alison Vickers, Ray Ashleigh, Stephen Butterfield, Ed Gamble, Jonathan Ghosh, Charles N McCollum, Mark Welch, Sarah Welsh, Leszek Wolowczyk, Mary Donnelly, Stephen D'Souza, Anselm A Egun, Bindu Gregary, Thomas Joseph, Christine Kelly, Shuja Punekar, M Asad Rahi, Sonia Raj, Dare Seriki, George Thomson, James Brown, Ragunath Durairajan, Iris Grunwald, Paul Guyler, Paula Harman, Matthew Jakeways, Christopher Khuoge, Ashish Kundu, Thayalini Loganathan, Nisha Menon, Raji O Prabakaran, Devesh Sinha, Vicky Thompson, Sharon Tysoe, Dennis Briley, Chris Darby, Linda Hands, Dominic Howard, Wilhelm Kuker, Ursula Schulz, Rachel Teal, David Barer, Andrew Brown, Susan Crawford, Paul Dunlop, Ramesh Krishnamurthy, Nikhil Majmudar, Duncan Mitchell, Min P Myint, Richard O'Brien, Janice O'Connell, Naweed Sattar, Shanmugam Vetrivel, Jonathan Beard, Trevor Cleveland, Peter Gaines, John Humphreys, Alison Jenkins, Craig King, Daniel Kusuma, Ralph Lindert, Robbie Lonsdale, Raj Nair, Shah Nawaz, Faith Okhuoya, Douglas Turner, Graham Venables, Paul Dorman, Andrea Hughes, Deborah Jones, David Mendelow, Helen Rodgers, Aidas Raudoniitis, Peter Enevoldson, Hans Nahser, Imelda O'Brien, Francesco Torella, Dave Watling, Richard White, Pauline Brown, Dipankar Dutta, Lorraine Emerson, Paula Hilltout, Sachin Kulkarni, Jackie Morrison, Keith Poskitt, Fiona Slim, Sarah Smith, Amanda Tyler, Joanne Waldron, Mark Whyman, Milda Bajoriene, Lucy Baker, Amanda Colston, Bekky Eliot-Jones, Gita Gramizadeh, Catherine Lewis-Clarke, Laura McCafferty, Deborah Oliver, Debbie Palmer, Abhijeet Patil, Suzannah Pegler, Gopi Ramadurai, Aisling Roberts, Tracey Sargent, Shivaprasad Siddegowda, Ravi Singh-Ranger, Akintunde Williams, Lucy Williams, Steve Windebank, Tadas Zuromskis, Lanka Alwis, Jane Angus, Asaipillai Asokanathan, Caroline Fornolles, Diana Hardy, Sophy Hunte, Frances Justin, Duke Phiri, Marie Mitabouana-Kibou, Lakshmanan Sekaran, Sakthivel Sethuraman, Margaret L Tate, Joyce Akyea-Mensah, Stephen Ball, Angela Chrisopoulou, Elizabeth Keene, Alison Phair, Steven Rogers, John V Smyth, Colin Bicknell, Jeremy Chataway, Nicholas Cheshire, Andrew Clifton, Caroline Eley, Richard Gibbs, Mohammad Hamady, Beth Hazel, Alex James, Michael Jenkins, Nyma Khanom, Austin Lacey, Maz Mireskandari, Joanna O'Reilly, Antony Pereira, Tina Sachs, John Wolfe, Philip Davey, Gill Rogers, Gemma Smith, Gareth Tervit, Ian Nichol, Andrew Parry, Gavin Young, Simon Ashley, James Barwell, Francis Dix, Azlisham M Nor, Chris Parry, Angela Birt, Paul Davies, Jim George, Anne Graham, Leon Jonker, Nicci Kelsall, Caroline Potts, Toni Wilson, Jamie Crinnion, Larissa Cuenoud, Nikola Aleksic, Srdan Babic, Nenad Ilijevski, Đorde Radak, Dragan Sagic, Slobodan Tanaskovic, Momcilo Colic, Vladimir Cvetic, Lazar Davidovic, Dejana R Jovanovic, Igor Koncar, Perica Mutavdžic, Miloš Sladojevic, Ivan Tomic, Eike S Debus, Ulrich Grzyska, Dagmar Otto, Götz Thomalla, Jessica Barlinn, Johannes Gerber, Kathrin Haase, Christian Hartmann, Stefan Ludwig, Volker Pütz, Christian Reeps, Christine Schmidt, Norbert Weiss, Sebastian Werth, Simon Winzer, Janine Gemper, Albrecht Günther, Bianka Heiling, Elisabeth Jochmann, Panagiota Karvouniari, Carsten Klingner, Thomas Mayer, Julia Schubert, Friederike Schulze-Hartung, Jürgen Zanow, Yvonne Bausback, Franka Borger, Spiridon Botsios, Daniela Branzan, Sven Bräunlich, Henryk Hölzer, Janin Lenzer, Christopher Piorkowski, Nadine Richter, Johannes Schuster, Dierk Scheinert, Andrej Schmidt, Holger Staab, Matthias Ulrich, Martin Werner, Hermann Berger, Gábor Biró, Hans-Henning Eckstein, Michael Kallmayer, Kornelia Kreiser, Alexander Zimmermann, Bärbel Berekoven, Klaus Frerker, Vera Gordon, Giovanni Torsello, Sebastian Arnold, Cora Dienel, Martin Storck, Bernhard Biermaier, Hans Martin Gissler, Christof Klötzsch, Tomas Pfeiffer, Ralph Schneider, Leander Söhl, Michael Wennrich, Angelika Alonso, Michael Keese, Christoph Groden, Andreas Cöster, Andreas Engelhardt, Christoph-Maria Ratusinski, Bengt Berg, Martin Delle, Johan Formgren, Peter Gillgren, Lotta Jarl, Torbjörn B Kall, Peter Konrad, Niklas Nyman, Claes Skiöldebrand, Johnny Steuer, Rabbe Takolander, Jonas Malmstedt, Stefan Acosta, Katarina Björses, Kerstin Brandt, Nuno Dias, Anders Gottsäter, Jan Holst, Thorarinn Kristmundsson, Tobias Kühme, Tilo Kölbel, Bengt Lindblad, Mats Lindh, Martin Malina, Tomas Ohrlander, Tim Resch, Viola Rönnle, Björn Sonesson, Margareta Warvsten, Zbigniew Zdanowski, Erik Campbell, Per Kjellin, Hans Lindgren, Johan Nyberg, Björn Petersen, Gunnar Plate, Håkan Pärsson, Peter Qvarfordt, Pavel Ignatenko, Andrey Karpenko, Vladimir Starodubtsev, Mikhail A Chernyavsky, Maria S Golovkova, Boris B Komakha, Nikolay N Zherdev, Andrey Belyasnik, Pavel Chechulov, Dmitry Kandyba, Igor Stepanishchev, Csaba Csobay-Novák, Edit Dósa, László Entz, Balázs Nemes, Zoltán Szeberin, Pál Barzó, Mihaly Bodosi, Eniko Fákó, Béla Fülöp, Tamás Németh, Szilárd Pazdernyik, Krisztina Skoba, Erika Vörös, Eleni Chatzinikou, Athanasios Giannoukas, Christos Karathanos, Stylianos Koutsias, Georgios Kouvelos, Miltiadis Matsagkas, Styliani Ralli, Christos Rountas, Nikolaos Rousas, Konstantinos Spanos, Elias Brountzos, John D Kakisis, Andreas Lazaris, Konstantinos G Moulakakis, Leonidas Stefanis, Georgios Tsivgoulis, Spyros Vasdekis, Constantine N Antonopoulos, Ion Bellenis, Dimitrios Maras, Antonios Polydorou, Victoria Polydorou, Antonios Tavernarakis, Nikolaos Ioannou, Maria Terzoudi, Miltos Lazarides, Michalis Mantatzis, Kostas Vadikolias, Lukasz Dzieciuchowicz, Marcin Gabriel, Zbigniew Krasinski, Grzegorz Oszkinis, Fryderyk Pukacki, Maciej Slowinski, Michal-Goran Stanišic, Ryszard Staniszewski, Jolanta Tomczak, Maciej Zielinski, Piotr Myrcha, Dorota Rózanski, Stanislaw Drelichowski, Wojciech Iwanowski, Katarzyna Koncewicz, Pawel Bialek, Zbigniew Biejat, Wojciech Czepel, Anna Czlonkowska, Anatol Dowzenko, Julia Jedrzejewska, Adam Kobayashi, Jerzy Leszczynski, Andrzej Malek, Jerzy Polanski, Robert Proczka, Maciej Skorski, Mieczyslaw Szostek, Piotr Andziak, Maciej Dratwicki, Robert Gil, Miroslaw Nowicki, Jaroslaw Pniewski, Jaroslaw Rzezak, Piotr Seweryniak, Pawel Dabek, Michal Juszynski, Grzegorz Madycki, Bartosz Pacewski, Witold Raciborski, Piotr Slowinski, Walerian Staszkiewicz, Martin Bombic, Vladimír Chlouba, Jirí Fiedler, Karel Hes, Petr Koštál, Jindrich Sova, Zdenek Kríž, Mojmír Prívara, Michal Reif, Robert Staffa, Robert Vlachovský, Bohuslav Vojtíšek, Tomáš Hrbác, Martin Kuliha, Václav Procházka, Martin Roubec, David Školoudík, David Netuka, Anna Šteklácová, Vladimír Beneš III, Pavel Buchvald, Ladislav Endrych, Miroslav Šercl, Walter Campos Jr, Ivan B Casella, Nelson de Luccia, André E V Estenssoro, Calógero Presti, Pedro Puech-Leão, Celso R B Neves, Erasmo S da Silva, Cid J Sitrângulo Jr, José A T Monteiro, Gisela Tinone, Marcelo Bellini Dalio, Edwaldo E Joviliano, Octávio M Pontes Neto, Mauricio Serra Ribeiro, Patrick Cras, Jeroen M H Hendriks, Mieke Hoppenbrouwers, Patrick Lauwers, Caroline Loos, Laetitia Yperzeele, Mia Geenens, Dimitri Hemelsoet, Isabelle van Herzeele, Frank Vermassen, Parla Astarci, Frank Hammer, Valérie Lacroix, André Peeters, Robert Verhelst, Silvana Cirelli, Pol Dormal, Annelies Grimonprez, Bart Lambrecht, Philipe Lerut, Eddy Thues, Guy De Koster, Quentin Desiron, Alain Maertens de Noordhout, Danielle Malmendier, Mireille Massoz, Georges Saad, Marc Bosiers, Joren Callaert, Koen Deloose, Estrella Blanco Cañibano, Beatriz García Fresnillo, Mercedes Guerra Requena, Pilar C Morata Barrado, Miguel Muela Méndez, Antonio Yusta Izquierdo, Fernando Aparici Robles, Paula Blanes Orti, Luis García Dominguez, Rafael Martínez López, Manuel Miralles Hernández, José I Tembl Ferrairo, Ángel Chamorro, Juan Macho, Víctor Obach, Vincent Riambau, Luis San Román, Frank J Ahlhelm, Kristine Blackham, Stefan Engelter, Thomas Eugster, Henrik Gensicke, Lorenz Gürke, Philippe Lyrer, Luigi Mariani, Marina Maurer, Edin Mujagic, Mandy Müller, Marios Psychogios, Peter Stierli, Christoph Stippich, Christopher Traenka, Thomas Wolff, Benjamin Wagner, Martina M Wiegert, Sandra Clarke, Michael Diepers, Ernst Gröchenig, Philipp Gruber, Andrej Isaak, Timo Kahles, Regula Marti, Krassen Nedeltchev, Luca Remonda, Nadir Tissira, Martina Valença Falcão, Gert J de Borst, Rob H Lo, Frans L Moll, Raechel Toorop, Bart H van der Worp, Evert J Vonken, Jaap L Kappelle, Ommid Jahrome, Floris Vos, Wouter Schuiling, Hendrik van Overhagen, Rudolf W M Keunen, Bob Knippenberg, Jan J Wever, Jan W Lardenoije, Michel Reijnen, Luuk Smeets, Steven van Sterkenburg, Gustav Fraedrich, Elke Gizewski, Ingrid Gruber, Michael Knoflach, Stefan Kiechl, Barbara Rantner, Timur Abdulamit, Patrice Bergeron, Raymond Padovani, Jean-Christophe Trastour, Jean-Marie Cardon, Anne Le Gallou-Wittenberg, Eric Allaire, Jean-Pierre Becquemin, Frédéric Cochennec-Paliwoda, Pascal Desgranges, Hassan Hosseini, Hicham Kobeiter, Jean Marzelle, Mohammed A Almekhlafi, Simerpreet Bal, Phillip A Barber, Shelagh B Coutts, Andrew M Demchuk, Muneer Eesa, Michelle Gillies, Mayank Goyal, Michael D Hill, Mark E Hudon, Anitha Jambula, Carol Kenney, Gary Klein, Marie McClelland, Alim Mitha, Bijoy K Menon, William F Morrish, Steven Peters, Karla J Ryckborst, Greg Samis, Supriya Save, Eric E Smith, Peter Stys, Suresh Subramaniam, Garnette R Sutherland, Tim Watson, John H Wong, L Zimmel, Vojko Flis, Jože Matela, Kazimir Miksic, Franko Milotic, Božidar Mrdja, Barbara Stirn, Erih Tetickovic, Mladen Gasparini, Anton Grad, Ingrid Kompara, Zoren Miloševic, Veronika Palmiste, Toomas Toomsoo, Balzhan Aidashova, Nursultan Kospanov, Roman Lyssenko, Daulet Mussagaliev, Rafi Beyar, Aaron Hoffman, Tony Karram, Arthur Kerner, Eugenia Nikolsky, Samy Nitecki, Silva Andonova, Chavdar Bachvarov, Vesko Petrov, Ivan Cvjetko, Vinko Vidjak, Damir Halužan, Mladen Petrunic, Bao Liu, Chang-Wei Liu, Daniel Bartko, Peter Beno, František Rusnák, Kamil Zelenák, Masayuki Ezura, Takashi Inoue, Naoto Kimura, Ryushi Kondo, Yasushi Matsumoto, Hiroaki Shimizu, Hidenori Endo, Eisuke Furui, Søren Bakke, Kristen Krohg-Sørensen, Terje Nome, Mona Skjelland, Bjørn Tennøe, João Albuquerque e Castro, Gonçalo Alves, Frederico Bastos Gonçalves, José de Aragão Morais, Ana C Garcia, Hugo Valentim, Leonor Vasconcelos, Fernando Belcastro, Fernando Cura, Patricio Zaefferer, Foad Abd-Allah, Mohamed H Eldessoki, Hussein Heshmat Kassem, Haytham Soliman Gharieb, Mary P Colgan, Syed N Haider, Joe Harbison, Prakash Madhavan, Dermot Moore, Gregor Shanik, Viviane Kazan, Munier Nazzal, Vicki Ramsey-Williams, ACST-2 Collaborative Group, Group, ACST-2 Collaborative, Halliday A., Bulbulia R., Bonati L.H., Chester J., Cradduck-Bamford A., Peto R., Pan H., Potter J., Henning Eckstein H., Farrell B., Flather M., Mansfield A., Mihaylova B., Rahimi K., Simpson D., Thomas D., Sandercock P., Gray R., Molyneux A., Shearman C.P., Rothwell P., Belli A., Herrington W., Judge P., Leopold P., Mafham M., Gough M., Cao P., MacDonald S., Bari V., Berry C., Bradshaw S., Brudlo W., Clarke A., Cox R., Fathers S., Gaba K., Gray M., Hayter E., Holliday C., Kurien R., Lay M., le Conte S., McManus J., Madgwick Z., Morris D., Munday A., Pickworth S., Ostasz W., Poorthuis M., Richards S., Teixeira L., Tochlin S., Tully L., Wallis C., Willet M., Young A., Casana R., Malloggi C., Odero A., Silani V., Parati G., Malchiodi G., Malferrari G., Strozzi F., Tusini N., Vecchiati E., Coppi G., Lauricella A., Moratto R., Silingardi R., Veronesi J., Zini A., Ferrero E., Ferri M., Gaggiano A., Labate C., Nessi F., Psacharopulo D., Viazzo A., Malacrida G., Mazzaccaro D., Meola G., Modafferi A., Nano G., Occhiuto M.T., Righini P., Stegher S., Chiarandini S., Griselli F., Lepidi S., Pozzi Mucelli F., Naccarato M., D'Oria M., Ziani B., Stella A., Dieng M., Faggioli G., Gargiulo M., Palermo S., Pini R., Puddu G.M., Vacirca A., Angiletta D., Desantis C., Marinazzo D., Mastrangelo G., Regina G., Pulli R., Bianchi P., Cireni L., Coppi E., Pizzirusso R., Scalise F., Sorropago G., Tolva V., Caso V., Cieri E., DeRango P., Farchioni L., Isernia G., Lenti M., Parlani G.B., Pupo G., Pula G., Simonte G., Verzini F., Carimati F., Delodovici M.L., Fontana F., Piffaretti G., Tozzi M., Civilini E., Poletto G., Reimers B., Praquin B., Ronchey S., Capoccia L., Mansour W., Sbarigia E., Speziale F., Sirignano P., Toni D., Galeotti R., Gasbarro V., Mascoli F., Rocca T., Tsolaki E., Bernardini G., DeMarco E., Giaquinta A., Patti F., Veroux M., Veroux P., Virgilio C., Mangialardi N., Orrico M., Di Lazzaro V., Montelione N., Spinelli F., Stilo F., Cernetti C., Irsara S., Maccarrone G., Tonello D., Visona A., Zalunardo B., Chisci E., Michelagnoli S., Troisi N., Masato M., Dei Negri M., Pacchioni A., Sacca S., Amatucci G., Cannizzaro A., Accrocca F., Ambrogi C., Barbazza R., Marcucci G., Siani A., Bajardi G., Savettieri G., Argentieri A., Corbetta R., Quaretti P., Thyrion F.Z., Cappelli A., Benevento D., De Donato G., Mele M.A., Palasciano G., Pieragalli D., Rossi A., Setacci C., Setacci F., Palombo D., Perfumo M.C., Martelli E., Paolucci A., Trimarchi S., Grassi V., Grimaldi L., La Rosa G., Mirabella D., Scialabba M., Sichel L., D'Angelo C.L., Fadda G.F., Kasemi H., Marino M., Burzotta F., Codispoti F.A., Ferrante A., Tinelli G., Tshomba Y., Vincenzoni C., Amis D., Anderson D., Catterson M., Clarke M., Davis M., Dixit A., Dyker A., Ford G., Jackson R., Kappadath S., Lambert D., Lees T., Louw S., McCaslin J., Parr N., Robson R., Stansby G., Wales L., Wealleans V., Wilson L., Wyatt M., Baht H., Balogun I., Burger I., Cosier T., Cowie L., Gunathilagan G., Hargroves D., Insall R., Jones S., Rudenko H., Schumacher N., Senaratne J., Thomas G., Thomson A., Webb T., Brown E., Esisi B., Mehrzad A., MacSweeney S., McConachie N., Southam A., Sunman W., Abdul-Hamiq A., Bryce J., Chetter I., Ettles D., Lakshminarayan R., Mitchelson K., Rhymes C., Robinson G., Scott P., Vickers A., Ashleigh R., Butterfield S., Gamble E., Ghosh J., McCollum C.N., Welch M., Welsh S., Wolowczyk L., Donnelly M., D'Souza S., Egun A.A., Gregary B., Joseph T., Kelly C., Punekar S., Rahi M.A., Raj S., Seriki D., Thomson G., Brown J., Durairajan R., Grunwald I., Guyler P., Harman P., Jakeways M., Khuoge C., Kundu A., Loganathan T., Menon N., Prabakaran R.O., Sinha D., Thompson V., Tysoe S., Briley D., Darby C., Hands L., Howard D., Kuker W., Schulz U., Teal R., Barer D., Brown A., Crawford S., Dunlop P., Krishnamurthy R., Majmudar N., Mitchell D., Myint M.P., O'Brien R., O'Connell J., Sattar N., Vetrivel S., Beard J., Cleveland T., Gaines P., Humphreys J., Jenkins A., King C., Kusuma D., Lindert R., Lonsdale R., Nair R., Nawaz S., Okhuoya F., Turner D., Venables G., Dorman P., Hughes A., Jones D., Mendelow D., Rodgers H., Raudoniitis A., Enevoldson P., Nahser H., O'Brien I., Torella F., Watling D., White R., Brown P., Dutta D., Emerson L., Hilltout P., Kulkarni S., Morrison J., Poskitt K., Slim F., Smith S., Tyler A., Waldron J., Whyman M., Bajoriene M., Baker L., Colston A., Eliot-Jones B., Gramizadeh G., Lewis-Clarke C., McCafferty L., Oliver D., Palmer D., Patil A., Pegler S., Ramadurai G., Roberts A., Sargent T., Siddegowda S., Singh-Ranger R., Williams A., Williams L., Windebank S., Zuromskis T., Alwis L., Angus J., Asokanathan A., Fornolles C., Hardy D., Hunte S., Justin F., Phiri D., Mitabouana-Kibou M., Sekaran L., Sethuraman S., Tate M.L., Akyea-Mensah J., Ball S., Chrisopoulou A., Keene E., Phair A., Rogers S., Smyth J.V., Bicknell C., Chataway J., Cheshire N., Clifton A., Eley C., Gibbs R., Hamady M., Hazel B., James A., Jenkins M., Khanom N., Lacey A., Mireskandari M., O'Reilly J., Pereira A., Sachs T., Wolfe J., Davey P., Rogers G., Smith G., Tervit G., Nichol I., Parry A., Young G., Ashley S., Barwell J., Dix F., Nor A.M., Parry C., Birt A., Davies P., George J., Graham A., Jonker L., Kelsall N., Potts C., Wilson T., Crinnion J., Cuenoud L., Aleksic N., Babic S., Ilijevski N., Radak, Sagic D., Tanaskovic S., Colic M., Cvetic V., Davidovic L., Jovanovic D.R., Koncar I., Mutavdzic P., Sladojevic M., Tomic I., Debus E.S., Grzyska U., Otto D., Thomalla G., Barlinn J., Gerber J., Haase K., Hartmann C., Ludwig S., Putz V., Reeps C., Schmidt C., Weiss N., Werth S., Winzer S., Gemper J., Gunther A., Heiling B., Jochmann E., Karvouniari P., Klingner C., Mayer T., Schubert J., Schulze-Hartung F., Zanow J., Bausback Y., Borger F., Botsios S., Branzan D., Braunlich S., Holzer H., Lenzer J., Piorkowski C., Richter N., Schuster J., Scheinert D., Schmidt A., Staab H., Ulrich M., Werner M., Berger H., Biro G., Eckstein H.-H., Kallmayer M., Kreiser K., Zimmermann A., Berekoven B., Frerker K., Gordon V., Torsello G., Arnold S., Dienel C., Storck M., Biermaier B., Gissler H.M., Klotzsch C., Pfeiffer T., Schneider R., Sohl L., Wennrich M., Alonso A., Keese M., Groden C., Coster A., Engelhardt A., Ratusinski C.-M., Berg B., Delle M., Formgren J., Gillgren P., Jarl L., Kall T.B., Konrad P., Nyman N., Skioldebrand C., Steuer J., Takolander R., Malmstedt J., Acosta S., Bjorses K., Brandt K., Dias N., Gottsater A., Holst J., Kristmundsson T., Kuhme T., Kolbel T., Lindblad B., Lindh M., Malina M., Ohrlander T., Resch T., Ronnle V., Sonesson B., Warvsten M., Zdanowski Z., Campbell E., Kjellin P., Lindgren H., Nyberg J., Petersen B., Plate G., Parsson H., Qvarfordt P., Ignatenko P., Karpenko A., Starodubtsev V., Chernyavsky M.A., Golovkova M.S., Komakha B.B., Zherdev N.N., Belyasnik A., Chechulov P., Kandyba D., Stepanishchev I., Csobay-Novak C., Dosa E., Entz L., Nemes B., Szeberin Z., Barzo P., Bodosi M., Fako E., Fulop B., Nemeth T., Pazdernyik S., Skoba K., Voros E., Chatzinikou E., Giannoukas A., Karathanos C., Koutsias S., Kouvelos G., Matsagkas M., Ralli S., Rountas C., Rousas N., Spanos K., Brountzos E., Kakisis J.D., Lazaris A., Moulakakis K.G., Stefanis L., Tsivgoulis G., Vasdekis S., Antonopoulos C.N., Bellenis I., Maras D., Polydorou A., Polydorou V., Tavernarakis A., Ioannou N., Terzoudi M., Lazarides M., Mantatzis M., Vadikolias K., Dzieciuchowicz L., Gabriel M., Krasinski Z., Oszkinis G., Pukacki F., Slowinski M., Stanisic M.-G., Staniszewski R., Tomczak J., Zielinski M., Myrcha P., Rozanski D., Drelichowski S., Iwanowski W., Koncewicz K., Bialek P., Biejat Z., Czepel W., Czlonkowska A., Dowzenko A., Jedrzejewska J., Kobayashi A., Leszczynski J., Malek A., Polanski J., Proczka R., Skorski M., Szostek M., Andziak P., Dratwicki M., Gil R., Nowicki M., Pniewski J., Rzezak J., Seweryniak P., Dabek P., Juszynski M., Madycki G., Pacewski B., Raciborski W., Slowinski P., Staszkiewicz W., Bombic M., Chlouba V., Fiedler J., Hes K., Kostal P., Sova J., Kriz Z., Privara M., Reif M., Staffa R., Vlachovsky R., Vojtisek B., Hrbac T., Kuliha M., Prochazka V., Roubec M., Skoloudik D., Netuka D., Steklacova A., Benes III V., Buchvald P., Endrych L., Sercl M., Campos W., Casella I.B., de Luccia N., Estenssoro A.E.V., Presti C., Puech-Leao P., Neves C.R.B., da Silva E.S., Sitrangulo C.J., Monteiro J.A.T., Tinone G., Bellini Dalio M., Joviliano E.E., Pontes Neto O.M., Serra Ribeiro M., Cras P., Hendriks J.M.H., Hoppenbrouwers M., Lauwers P., Loos C., Yperzeele L., Geenens M., Hemelsoet D., van Herzeele I., Vermassen F., Astarci P., Hammer F., Lacroix V., Peeters A., Verhelst R., Cirelli S., Dormal P., Grimonprez A., Lambrecht B., Lerut P., Thues E., De Koster G., Desiron Q., Maertens de Noordhout A., Malmendier D., Massoz M., Saad G., Bosiers M., Callaert J., Deloose K., Blanco Canibano E., Garcia Fresnillo B., Guerra Requena M., Morata Barrado P.C., Muela Mendez M., Yusta Izquierdo A., Aparici Robles F., Blanes Orti P., Garcia Dominguez L., Martinez Lopez R., Miralles Hernandez M., Tembl Ferrairo J.I., Chamorro A., Macho J., Obach V., Riambau V., San Roman L., Ahlhelm F.J., Blackham K., Engelter S., Eugster T., Gensicke H., Gurke L., Lyrer P., Mariani L., Maurer M., Mujagic E., Muller M., Psychogios M., Stierli P., Stippich C., Traenka C., Wolff T., Wagner B., Wiegert M.M., Clarke S., Diepers M., Grochenig E., Gruber P., Isaak A., Kahles T., Marti R., Nedeltchev K., Remonda L., Tissira N., Valenca Falcao M., de Borst G.J., Lo R.H., Moll F.L., Toorop R., van der Worp B.H., Vonken E.J., Kappelle J.L., Jahrome O., Vos F., Schuiling W., van Overhagen H., Keunen R.W.M., Knippenberg B., Wever J.J., Lardenoije J.W., Reijnen M., Smeets L., van Sterkenburg S., Fraedrich G., Gizewski E., Gruber I., Knoflach M., Kiechl S., Rantner B., Abdulamit T., Bergeron P., Padovani R., Trastour J.-C., Cardon J.-M., Le Gallou-Wittenberg A., Allaire E., Becquemin J.-P., Cochennec-Paliwoda F., Desgranges P., Hosseini H., Kobeiter H., Marzelle J., Almekhlafi M.A., Bal S., Barber P.A., Coutts S.B., Demchuk A.M., Eesa M., Gillies M., Goyal M., Hill M.D., Hudon M.E., Jambula A., Kenney C., Klein G., McClelland M., Mitha A., Menon B.K., Morrish W.F., Peters S., Ryckborst K.J., Samis G., Save S., Smith E.E., Stys P., Subramaniam S., Sutherland G.R., Watson T., Wong J.H., Zimmel L., Flis V., Matela J., Miksic K., Milotic F., Mrdja B., Stirn B., Tetickovic E., Gasparini M., Grad A., Kompara I., Milosevic Z., Palmiste V., Toomsoo T., Aidashova B., Kospanov N., Lyssenko R., Mussagaliev D., Beyar R., Hoffman A., Karram T., Kerner A., Nikolsky E., Nitecki S., Andonova S., Bachvarov C., Petrov V., Cvjetko I., Vidjak V., Haluzan D., Petrunic M., Liu B., Liu C.-W., Bartko D., Beno P., Rusnak F., Zelenak K., Ezura M., Inoue T., Kimura N., Kondo R., Matsumoto Y., Shimizu H., Endo H., Furui E., Bakke S., Krohg-Sorensen K., Nome T., Skjelland M., Tennoe B., Albuquerque e Castro J., Alves G., Bastos Goncalves F., de Aragao Morais J., Garcia A.C., Valentim H., Vasconcelos L., Belcastro F., Cura F., Zaefferer P., Abd-Allah F., Eldessoki M.H., Heshmat Kassem H., Soliman Gharieb H., Colgan M.P., Haider S.N., Harbison J., Madhavan P., Moore D., Shanik G., Kazan V., Nazzal M., Ramsey-Williams V., and Gargiulo M

Subjects
Male, medicine.medical_specialty, Time Factors, Time Factor, medicine.medical_treatment, Carotid Stenosi, MEDLINE, Carotid endarterectomy, Rate ratio, Risk Assessment, Asymptomatic, law.invention, Randomized controlled trial, law, Risk Factors, carotid artery stenting (CAS), carotid endarterectomy (CEA), Stent, medicine, Humans, Carotid Stenosis, Stroke, Endarterectomy, Aged, Endarterectomy, Carotid, business.industry, carotid artery, Risk Factor, Articles, General Medicine, trial, medicine.disease, Settore MED/22 - CHIRURGIA VASCOLARE, Surgery, Stenosis, Treatment Outcome, Settore MED/11 - MALATTIE DELL'APPARATO CARDIOVASCOLARE, Female, Stents, Human medicine, medicine.symptom, business, Human
Abstract

Summary Background Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either carotid artery stenting (CAS) or carotid endarterectomy (CEA) can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death. Comparison of their long-term protective effects requires large-scale randomised evidence. Methods ACST-2 is an international multicentre randomised trial of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. Patients were eligible if they had severe unilateral or bilateral carotid artery stenosis and both doctor and patient agreed that a carotid procedure should be undertaken, but they were substantially uncertain which one to choose. Patients were randomly allocated to CAS or CEA and followed up at 1 month and then annually, for a mean 5 years. Procedural events were those within 30 days of the intervention. Intention-to-treat analyses are provided. Analyses including procedural hazards use tabular methods. Analyses and meta-analyses of non-procedural strokes use Kaplan-Meier and log-rank methods. The trial is registered with the ISRCTN registry, ISRCTN21144362. Findings Between Jan 15, 2008, and Dec 31, 2020, 3625 patients in 130 centres were randomly allocated, 1811 to CAS and 1814 to CEA, with good compliance, good medical therapy and a mean 5 years of follow-up. Overall, 1% had disabling stroke or death procedurally (15 allocated to CAS and 18 to CEA) and 2% had non-disabling procedural stroke (48 allocated to CAS and 29 to CEA). Kaplan-Meier estimates of 5-year non-procedural stroke were 2·5% in each group for fatal or disabling stroke, and 5·3% with CAS versus 4·5% with CEA for any stroke (rate ratio [RR] 1·16, 95% CI 0·86–1·57; p=0·33). Combining RRs for any non-procedural stroke in all CAS versus CEA trials, the RR was similar in symptomatic and asymptomatic patients (overall RR 1·11, 95% CI 0·91–1·32; p=0·21). Interpretation Serious complications are similarly uncommon after competent CAS and CEA, and the long-term effects of these two carotid artery procedures on fatal or disabling stroke are comparable. Funding UK Medical Research Council and Health Technology Assessment Programme.

Published
2021

11. Biophysical investigations into membrane-active peptides and proteins

Author

Yin, D, Watts, A, Judge, P, and Ryadnov, M

Abstract

The inexorable spread of antibiotic or antimicrobial resistance is a global problem, described by the UK Chief Medical Officer to be "as big a threat as terrorism". Due to uncontrolled, unnecessary overuse of antibiotics in medicine and agriculture, bacterial resistance has evolved to even the antibiotics of last resort. Antimicrobial peptides (AMPs) are a promising class of organic molecule that have been proposed to exert a potent antimicrobial effect, which, directly or indirectly, involve complex interactions with cell membranes. Three broad mechanisms have been proposed for AMPs: carpet, barrel-stave and toroidal pore. However, the molecular basis for the mode of action of AMPs, and the relationship between primary structure and antimicrobial activity, remains poorly understood. In this thesis, interactions of membrane-active peptides and proteins with model lipid membranes are studied, to understand better the peptide-lipid interactions of two de novo AMPs and a functionally related protein puroindoline-b (pinB), which is implicated in antimicrobial plant defence. Quartz crystal microbalance (QCM), solid-state nuclear magnetic resonance (ssNMR), electron paramagnetic resonance (EPR) and neutron reflectivity (NR) are used to achieve this. The two AMPs were designed rationally with their primary structure predicted to display specific peptide-lipid interactions. Tilamin (tilted antimicrobial insert) was designed by modifying amhelin (antimicrobial insert), a pore-forming AMP. The modified peptide was predicted to disrupt model membranes mimicking bacterial membranes via a different mode of action to transmembrane barrel stave pore formation. Chom (chopped cecropin mutant) was designed by shortening the length of a natural AMP, cecropin-B, and was predicted to operate via a carpet mechanism. To model the biophysical properties such as morphology, thickness and charge of native membranes, simplified phospholipid liposomes were used to better understand the membrane-perturbing influence of the AMPs, and whether this was correlated with antimicrobial activity. In the presence of anionic model membranes (mimicking Gram-negative inner membranes and Gram-positive membranes), tilamin and chom adopt amphipathic alpha helix conformations as determined by circular dichroism, while remaining unstructured in solution and in the presence of zwitterionic model membranes mimicking mammalian model membranes. Adoption of a folded conformation appears to be important for the lytic effect of the AMPs. Calcein leakage experiments performed show that the AMPs induce leakage of calcein from the interior of anionic liposomes, consistent with the proposal that membrane permeabilisation is important for antimicrobial activity. The peptide-lipid interactions of the AMPs were then probed using QCM and ssNMR, giving mechanistic evidence that chom operates via the carpet mechanism as predicted. The nature of the mode of action of tilamin remained uncertain. From order parameters of lipids in bilayers, obtained using ssNMR upon interaction with tilamin, a toroidal pore mechanism was proposed, along with a new mode of action that caused monoleaflet poration, though it was not possible to resolve the two mechanism based on data obtained from symmetrical vesicles alone. Adapting a newly established protocol to control the leaflet distribution of lipids in model membranes, an asymmetrically distributed nitroxide probe reveals for the first time leaflet-specific peptide-lipid interactions using cw-EPR. Tilamin shows changes in bilayer lipid order parameters that do not match those seen for either an all-surface or transmembrane control peptide, indicating more complex interactions. Unique QCM data, heterogeneous changes in order parameter profiles observed with acylchain 2H ssNMR, as well as a lack of interaction with the inner leaflets of anionic model membranes seen by cw-EPR taken in combination suggest tilamin operates via a more complicated mechanism. Supported by tilt angles obtained by geometric analysis of labelled alanines (GALA) of deuterium-labelled tilamin and atomic force microscopy (AFM) imaging performed with collaborators, the results are consistent with a new mechanism; monolayer poration. The puroindolines are also studied, due to their potential role as antimicrobial proteins in food safety, and in controlling wheat endosperm texture. The mode of insertion of wild-type puroindoline-B (pinB+) and a single-point mutant (pinBs) into bacterial model bilayers was probed for the first time with ssNMR, EPR and NR. In contrast to previous work on monolayers, pinBs does not cause changes in bilayer lipid order in the gel phase, while pinB+ forms a protein layer on the surface of a membrane. The results suggest that in more native-like model membranes, the tryptophan-rich domain (TRD) of pinBs and pinB+ greatly affects the membrane binding properties, with implications for the role of the proteins in vivo.

Published
2017

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