Impact of therapeutic X-ray exposure on collagen I and associated proteins.

Biological tissues are exposed to X-rays in medical applications (such as diagnosis and radiotherapy) and in research studies (for example microcomputed X-ray tomography: microCT). Radiotherapy may deliver doses up to 50Gy to both tumour and healthy tissues, resulting in undesirable clinical side effects which can compromise quality of life. Whilst cellular responses to X-rays are relatively well-characterised, X-ray-induced structural damage to the extracellular matrix (ECM) is poorly understood.

Image quality and scan time optimisation for in situ phase contrast x-ray tomography of the intervertebral disc.

In-line phase contrast synchrotron tomography combined with in situ mechanical loading enables the characterisation of soft tissue micromechanics via digital volume correlation (DVC) within whole organs. Optimising scan time is important for reducing radiation dose from multiple scans and to limit sample movement during acquisition. Also, although contrasted edges provided by in-line phase contrast tomography of soft tissues are useful for DVC, the effect of phase contrast imaging on its accuracy has yet to be investigated.

The fatal trajectory of pulmonary COVID-19 is driven by lobular ischemia and fibrotic remodelling.

Background: COVID-19 is characterized by a heterogeneous clinical presentation, ranging from mild symptoms to severe courses of disease. 9-20% of hospitalized patients with severe lung disease die from COVID-19 and a substantial number of survivors develop long-COVID. Our objective was to provide comprehensive insights into the pathophysiology of severe COVID-19 and to identify liquid biomarkers for disease severity and therapy response.

Regional variations in discrete collagen fibre mechanics within intact intervertebral disc resolved using synchrotron computed tomography and digital volume correlation.

Many soft tissues, such as the intervertebral disc (IVD), have a hierarchical fibrous composite structure which suffers from regional damage. We hypothesise that these tissue regions have distinct, inherent fibre structure and structural response upon loading. Here we used synchrotron computed tomography (sCT) to resolve collagen fibre bundles (∼5μm width) in 3D throughout an intact native rat lumbar IVD under increasing compressive load.