University of Leeds 9 articles published in JoVE Medicine Drug Treatment by Central Venous Catheter in a Mouse Model of Angiotensin II Induced Abdominal Aortic Aneurysm and Monitoring by 3D Ultrasound Nahla Ibrahim1, Johannes Klopf1, Sonja Bleichert1, Marc A. Bailey2,3, Albert Busch4, Alexander Stiglbauer-Tscholakoff5, Wolf Eilenberg1, Christoph Neumayer1, Christine Brostjan1 1Division of Vascular Surgery, Department of General Surgery, Medical University of Vienna and Vienna General Hospital, 2Leeds Institute for Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, 3Leeds Vascular Institute, Leeds General Infirmary, 4Department for Visceral, Thoracic and Vascular Surgery, Technical University of Dresden and University Hospital Carl-Gustav Carus, 5Division of Cardiovascular and Interventional Radiology, Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna and Vienna General Hospital This protocol describes the consecutive implantation of an osmotic pump to induce abdominal aortic aneurysm by angiotensin II release in apolipoprotein E (ApoE) deficient mice and of a vascular access port with a jugular vein catheter for repeated drug treatment. Monitoring of aneurysm development by 3D ultrasound is effectively conducted despite dorsal implants. Biochemistry Fast Grid Preparation for Time-Resolved Cryo-Electron Microscopy David P. Klebl1, Frank Sobott2, Howard D. White3, Stephen P. Muench1 1School of Biomedical Sciences, Faculty of Biological Sciences & Astbury Centre for Structural and Molecular Biology, University of Leeds, 2School of Molecular and Cellular Biology, Faculty of Biological Sciences & Astbury Centre for Structural and Molecular Biology, University of Leeds, 3Department of Physiological Sciences, Eastern Virginia Medical School Here, we provide a detailed protocol for the use of a rapid grid making device for both fast grid-making and for rapid mixing and freezing to conduct time-resolved experiments. Biochemistry Single Particle Cryo-Electron Microscopy: From Sample to Structure Joshua B.R. White1, Daniel P. Maskell1, Andrew Howe2, Martin Harrow2, Daniel K. Clare2, C. Alistair Siebert2, Emma L. Hesketh1, Rebecca F. Thompson1 1Astbury Centre Structural Molecular Biology, School Molecular and Cellular Biology, Faulty Biological Sciences, University of Leeds, 2Diamond Light Source, Harwell Science and Innovation Campus Structure determination of macromolecular complexes using cryoEM has become routine for certain classes of proteins and complexes. Here, this pipeline is summarized (sample preparation, screening, data acquisition and processing) and readers are directed towards further detailed resources and variables that may be altered in the case of more challenging specimens. Biochemistry Screening for Thermotoga maritima Membrane-Bound Pyrophosphatase Inhibitors Keni Vidilaseris*1, Niklas G. Johansson*2, Ainoleena Turku2, Alexandros Kiriazis2, Gustav Boije af Gennäs2, Jari Yli-Kauhaluoma2, Henri Xhaard2, Adrian Goldman1,3 1Research Program in Molecular and Integrative Biosciences, University of Helsinki, 2Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, 3School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds Here we present a screening method for membrane-bound pyrophosphatase (from Thermotoga maritima) inhibitors based on the molybdenum blue reaction in a 96 well plate format. Biochemistry Single Liposome Measurements for the Study of Proton-Pumping Membrane Enzymes Using Electrochemistry and Fluorescent Microscopy Ievgen Mazurenko1, Nikos S. Hatzakis2, Lars J.C. Jeuken1 1School of Biomedical Sciences & the Astbury Centre for Structural Molecular Biology, University of Leeds, 2Department of Chemistry and Nano-Science Center, University of Copenhagen Here, we present a protocol to study the molecular mechanism of proton translocation across lipid membranes of single liposomes, using cytochrome bo3 as an example. Combining electrochemistry and fluorescence microscopy, pH changes in the lumen of single vesicles, containing single or multiple enzyme, can be detected and analyzed individually. Engineering Controllable Nucleation of Cavitation from Plasmonic Gold Nanoparticles for Enhancing High Intensity Focused Ultrasound Applications James R. McLaughlan1,2 1School of Electronic and Electrical Engineering, University of Leeds, 2Leeds Institute of Cancer and Pathology, University of Leeds This protocol demonstrates the controllable nucleation of cavitation in gel phantoms, through simultaneous exposure to both near-infrared pulsed laser light and high intensity focused ultrasound (HIFU). The cavitation activity can then be used for enhancing imaging and/or therapeutic uses of HIFU. Biochemistry Variations on Negative Stain Electron Microscopy Methods: Tools for Tackling Challenging Systems Charlotte A. Scarff1, Martin J. G. Fuller2, Rebecca F. Thompson2, Matthew G. Iadanza1 1Astbury Centre for Structural Molecular Biology, University of Leeds, 2Astbury Biostructure Laboratory, University of Leeds Negative stain EM is a powerful technique for visualizing macromolecular structure, but different staining techniques can produce varying results in a sample dependent manner. Here several negative staining approaches are described in detail to provide an initial workflow for tackling the visualization of challenging systems. Chemistry Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes Yogita Patil-Sen1, Amin Sadeghpour2, Michael Rappolt2, Chandrashekhar V. Kulkarni1 1Centre for Materials Science, School of Physical Sciences and Computing, University of Central Lancashire, 2School of Food Science & Nutrition, University of Leeds We report on a smart application of carbon nanotubes for kinetic stabilization of lipid particles that contain self-assembled nanostructures in their cores. The preparation of lipid particles requires rather low concentrations of carbon nanotubes permitting their use in biomedical applications such as drug delivery. Engineering Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers Chantal Le Graët1, Mark A. de Vries1,2, Mathew McLaren1,3, Richard M.D. Brydson3, Melissa Loving4, Don Heiman5, Laura H. Lewis4, Christopher H. Marrows1 1School of Physics and Astronomy, University of Leeds, 2Institute of Materials Research, University of Leeds, 3School of Chemistry, University of Edinburgh, 4Department of Chemical Engineering, Northeastern University, 5Department of Physics, Northeastern University A method to prepare epitaxial layers of ordered alloys by sputtering is described. The B2-ordered FeRh compound is used as an example, as it displays a metamagnetic transition that depends sensitively on the degree of chemical order and the exact composition of the alloy.
