Ischaemic heart disease is a major healthcare issue, resulting globally in 12.2% of all deaths, but rising to a massive 16.3% amongst the wealthiest countries. This makes it the leading cause of death and with an aging population this is expected to remain a major issue. Bio-medical research is at the forefront of the movement to understand the onset of heart conditions, trauma and their treatment, and includes detailed studies at the cellular level. Pivotal in these studies is the ability to simulate these conditions and examine the membrane integrity and viability of the cardiac myocyte, the contractile cell from the heart. This project will develop a tool to facilitate these studies using acoustically induced fluid flows which produce sub-millimeter sized vortex flows, termed ultrasonic micro-streaming , to generate shear forces within the cell membrane; by introducing and manipulating micro-streaming sources such as micro-bubbles, it will be shown how ultrasonic streaming can be targeted at isolated cardiac myocyte cells to either test their integrity or induce a controlled level of trauma to test subsequent cardioprotective treatments and restoration of cell function.

Analytical ultracentrifugation (AUC) is a powerful method that enables protein association or degradation in solution to be studied in detail. Protein samples are inserted into a cell assembly with windows at the top and bottom. The cells are placed into a titanium rotor which is then spun at speeds up to 50,000 revs per min inside the analytical ultracentrifuge. Optical systems are used to observe the protein in either high-speed or low-speed experiments in which the protein slowly moves to the outside of the rotor, being continuously observed as it moves. Up to 200-500 scans are recorded during the experiment. The high speed 'velocity' experiments measure how quickly the protein moves to the bottom of the cell, from which we learn about the shape of the protein, and how many different species exist in the sample. This is especially useful for analysing complexes formed between different proteins, or discovering how many different types of proteins are present in the sample, and whether they are associated or cleaved. The low speed 'equilibrium' experiments balance the tendency of the protein to diffuse in the cell with that to sediment to the bottom of the cell. This data tells us about the size of the protein in solution and the strength of any associative behaviour in the sample. Modern AUC instrumentation provides a wealth of new information on proteins that can be deciphered using new powerful software packages. For example, all the velocity scans can be inputted into software such as SEDFIT, as the result of which all the macromolecular species present in the solution can be identified, even the minor ones. We can then dissect the formation of protein complexes in detail, including determining the association constants for their formation, or follow protein degradation or cleavage in other cases. Other software such as SEDANAL or SEDPHAT analyses equilibrium scans in detail. Hence the modern AUC makes possible new types of experiments in which protein complexes can be studied as a function of many biologically important variables such as cofactors and inhibitors in order to clarify the mechanisms responsible for activity and function. The requested AUC will be applied to key problems. In the complement immune defence system of the body, we will analyse the multiple interactions made by an abundant regulator of complement activation called Factor H with its targets. The biology of Factor H is important as this has been implicated in inflammatory disorders related to blindness and kidney failure, so the ability to control its behaviour has great advantages. Antibodies are also important in immunology. We can use AUC data to understand better the way in which antibodies recognise foreign material that invades the body and how antibodies bind to cell surface receptors to control the immune response. Enzymes are important in many industrial applications, so it becomes essential to discover novel ways of creating more robust versions that will perform their chemical reactions. The AUC will help us identify enzymes that have been re-engineered to be more stable. We will use the AUC to study how specialised human proteins called TIP48 and TIP49 associate with each other and how this is modified by small molecules. Both proteins use chemical energy to perform their role in large nuclear complexes. Oligomerisation is crucial to couple ATP hydrolysis to the molecular action of these proteins. A heat-stable form of TIP49 in archaeal organisms will be studied to discover both the importance of these small molecules for association processes and also the effect of deleting part of TIP49 on its subunit organisation. A different set of proteins are involved in mitosis, the process of cell division. The AUC will be invaluable for defining how these mitotic complexes are formed and their stability, and this work is crucial to lead to more detailed molecular structures that will be determined by other methods.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Ultrasonic Standing Waves (USWs) can be used to manipulate particles within a fluid. Used within chambers of a half wavelength depth or less, the ultrasonic radiation forces can move the particles either to a central plane within the chamber or to a wall of the chamber. This project is a multidisciplinary investigation into the use of USWs in microfluidic biosensing applications. It involves the School of Engineering Sciences (SES), the Optoelectronics Research Centre (ORC) and the Microelectronics Research Centre in the Department of Electronics and Computer Science (ECS) at the University of Southampton. The work aims to integrate optical sensing and USW excitation using techniques and materials compatible with emerging microfluidic technology. It will also use the optical/USW techniques to study and quantify the behaviour of the USW chamber, particularly with regard to the ability of quarter wavelength chambers to move particles to the chamber wall. The project will apply these techniques to the detection of a number of DNA sequences in a mixture. It will also investigate the feasibility of using acoustic radiation forces to interrogate single DNA sequences with a high resolution.