The aorta is the largest conduit for blood flow in the human body and vital for cardiovascular health. The mechanical properties of the aorta are critical for cardiovascular health. In vivo, the compliance of the aorta can be measured using techniques such as pulse wave velocity (PWV). In fact, arterial compliance measured via PWV has been indicated as an early cardiovascular risk marker and has potential for assessing the effects of pharmacological interventions on the cardiovascular system .
One area where PWV is yet to be fully explored is for assessing the risk of the aorta rupturing. Thoracic aortic aneurysms (TAAs) are a difficult to detect but potentially lethal condition where the aorta balloons significantly in size. They are typically detected where patients undergo medical examination for other reasons. The criteria for patients being selected for surgery for TAAs is based on the size (diameter) that the aorta expands too. This is now seen as a poor indicator for determining risk of rupture .
This project will focus on develop a novel screening tool by combining in vivo measurements of aortic stiffness via PWV with structural and biochemical characterisation of the aorta through ex vivo testing of the aortic wall.
The objective of this inter-disciplinary PhD project is to investigate the role of arterial compliance in the development of, and progression of TAAs. The specific objectives of this PhD are:
- To develop a relationship between in vivo arterial compliance and TAA.
- To relate the arterial compliance to the properties of the aneurysmal aortic wall.
- To develop a novel screening tool for TAAs based on aortic biomechanics.
In this project, a number of high spatial resolution techniques will be applied to study multi-scale structural features and mechanical properties of aortic tissue , along with developing skills in PWV. To determine topographical and biomechanical alterations in TAAs, we will employ advanced atomic force microscopy (AFM) based PeakForce Quantitative Nanomechanical Mapping (PFQNM) technique to investigate nano-scale changes associated with in vivo alterations in arterial compliance. PFQNM enables the co-localization of ultrastructural and mechanical properties with a high resolution. Optical microscopy, SEM and TEM will be utilized to observe the nano-/micro-structure of the aorta, focusing on collagen fibril organisation.
The successful candidate will join the LABB Group (Liverpool Aortic Biomechanics and Biochemistry Research Group), www.labb-group.com, a multidisciplinary group with expertise in aortic biomechanics, biochemistry and surgery. The LABB group has members from University of Liverpool, Royal University Liverpool Hospital and Liverpool Heart and Chest Hospital. The candidate will join the Liverpool Centre for Cardiovascular Science, a large active group of researchers and clinicians and will join their monthly meetings. The candidate will be expected to work closely with cardiothoracic surgeons and undergo training for harvesting tissue from patients undergoing elective surgery with full ethical approval.
Open to students worldwide
This project is for self-funded students only, for example, through government-awarded scholarships. Tuition fees can be found on the following page: https://www.liverpool.ac.uk/study/postgraduate-research/fees-and-funding/fees-and-costs/
Bench fees will be £3000 per annum.
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