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Rosalia, L.

Publications and source records attributed to Rosalia, L..

2 recordsLinked to original sources

Soft robotics-enabled large animal model of HFpEF hemodynamics for device testing

Heart failure with preserved ejection fraction (HFpEF) is a major challenge in cardiovascular medicine, accounting for approximately 50% of all cases of heart failure. Due to the lack of effective therapies for this condition, the mortality associated with HFpEF remains higher than that of most cancers. Despite the ongoing efforts, no medical device has yet received FDA approval. This is largely due to the lack of an in vivo model of the HFpEF hemodynamics, resulting in the inability to evaluate device effectiveness in vivo prior to clinical trials. Here, we describe the development of a highly tunable porcine model of HFpEF hemodynamics using implantable soft robotic sleeves, where controlled actuation of a left ventricular and an aortic sleeve can recapitulate changes in ventricular compliance and afterload associated with a broad spectrum of HFpEF hemodynamic phenotypes. We demonstrate the feasibility of the proposed model in preclinical testing by evaluating the hemodynamic response of the model post-implantation of an interatrial shunt device, which was found to be consistent with findings from in silico studies and clinical trials. This work addresses several of the limitations associated with previous models of HFpEF, such as their limited hemodynamic fidelity, elevated costs, lengthy development time, and low throughput. By showcasing exceptional versatility and tunability, the proposed platform has the potential to revolutionize the current approach for HFpEF device development and selection, with the goal of improving the quality of life for the 32 million people affected by HFpEF worldwide.

bioengineering↗

A magnetically actuated, optically sensed tensile testing method for mechanical characterisation of soft biological tissues

Mechanical properties of soft biological tissues play a key role in their normal physiology, contributing to their formation during development, maintenance and repair during adult homeostasis, and driving diseases such as cancer. Mechanics has been proposed to exert its effect by impacting cells fate decisions and cell behaviours including proliferation, differentiation and motility, amongst others. However, despite its critical relevance, a comprehensive analysis of the biomechanics of soft biological tissues is still lacking due to the limitations of the existing characterisation tools. In this article, we describe the development of a device for uniaxial tensile testing of small samples of epithelial and connective tissues, based on the closed-loop interaction between an electromagnetic force actuator and an optical strain sensor. First, we validate the device with synthetic elastomers of known mechanical properties and compare its performance with conventional tensile testing methods; then, we characterise the mechanical properties of the squamous epithelium of the mouse oesophagus along with its supporting connective tissue and underlying muscle in controlled environmental conditions. Through an analysis of strain-stress curves, we demonstrate that the whole oesophagus behaves as a trilayered composite material, whose overall mechanical response depends on the properties of each of its tissue layers. Overall, the proposed setup enables measurements of the mechanical properties of soft biological tissues with unprecedented reliability and precision, and offers an ideal platform for future instrument developments.

biophysics↗