Temperature modulation of skin tolerance to applied mechanical loading and shear

压力性溃疡（PU）是由躺下、坐着或佩戴医疗器械（如面罩）时长时间的压力和剪切引起的皮肤局部损伤。PU可以影响任何人，特别是那些由于住院而经历长期不动的人，从婴儿到老年人。PU使人们的生活质量恶化，并且对NHS等医疗保健提供者来说也非常昂贵。事实上，在英国，治疗皮肤伤口（包括PU）的年度成本估计为每年约83亿英镑。因此，提高我们对人体皮肤如何对压力做出反应的理解，将有助于开发具有成本效益的个性化解决方案，以保持皮肤健康。冷却皮肤是一种很有前途的方法，可以提高皮肤对长时间压力（例如卧床不起）或反复摩擦坚硬表面（即剪切应力）引起的损伤的恢复力。早期的动物研究表明，冷却皮肤可以降低发生PU的风险，这一点最近在初步的人类研究中得到了证实。然而，我们仍然不知道为什么以及如何冷却使皮肤对压力和剪切更有弹性。此外，冷却皮肤可能是不舒服的，这可能限制治疗的可接受性，特别是在有发展PU风险的脆弱人群中，如老年人和脊髓损伤患者。这种知识差距提出了一系列基本的生物学问题，这些问题对预防PU以及开发控制皮肤温度并帮助在整个生命过程中保持皮肤健康的新设备具有明确的意义。这些问题是：-冷却如何改变血管，免疫，结构和感知皮肤的反应，机械侮辱？- 对冷却的反应是否会随着年龄的增长和脊髓损伤的存在而变化，这两者都会增加获得PU的风险？我们能否确定一个既有益又舒适的冷却水平，以保护皮肤免受压力和剪切损伤？我们的项目将回答这些问题并填补这些知识空白。我们的目标是更好地了解当皮肤受到压力和剪切时，冷却如何影响皮肤的功能和舒适度，以及这如何随年龄和临床状态而变化。我们设计了一系列的实验，在年轻和老年参与者，并在那些脊髓损伤，以回答我们的研究问题。我们的第一个目标是研究不同水平的冷却如何改变皮肤对持续压力和重复剪切应力的血管、炎症、结构和感知反应。我们的第二个目标是确定衰老和脊髓损伤的存在如何调节皮肤的生理和感知反应，这些反应是冷却对皮肤对压力和剪切耐受性的有益影响的基础。我们的项目将开发关于温度在降低皮肤损伤风险方面的作用的新的基础知识。这将支持医疗保健和以用户为中心的技术的设计创新，例如支持床垫，服装和可以控制皮肤温度的医疗设备。这将释放冷却皮肤的潜力，有助于在整个生命过程中保持皮肤健康。

Pressure ulcers (PUs) are a localised damage to the skin resulting from prolonged periods of pressure and shear when lying, sitting, or wearing a medical device such as a face mask. PUs can affect any individual, particularly those who experience prolonged immobility due to hospitalisation, ranging from babies to elderly adults. PUs worsen people's quality of life and they are also very costly to healthcare providers such as the NHS. Indeed, in the UK, the annual cost of treating skin wounds, including PUs, has been estimated to be approximately £8.3 billion a year. Accordingly, improving our understanding of how the human skin respond to pressure could lead to the development of cost-effective, personalised solutions to maintain skin health.Cooling the skin is a promising approach to increase the skin's resilience to damage induced by prolonged periods of pressure (e.g. when one is bedridden) or repeated rubbing against a hard surface (i.e. shear stress). Early animal studies showed that cooling the skin reduces the risk of developing a PU, and this has been more recently confirmed in preliminary human studies. Yet, we still do not know enough about why and how cooling makes the skin more resilient to pressure and shear. Furthermore, cooling the skin can be uncomfortable and this can limit how acceptable the therapy is, particularly amongst vulnerable people at risk of developing PUs such as the elderly and those with a spinal cord injury. This knowledge gap raises a series of basic biological questions, which have clear implications for the prevention of PUs, and for the development of new devices that control skin temperature and help maintaining skin health across the life course. These questions are: - How does cooling change the vascular, immunological, structural, and perceptual responses of the skin to a mechanical insult? - Do the responses to cooling change with ageing and with the presence of a spinal cord injury, both of which increase the risk of acquiring a PU?- Can we identify a level of cooling that is both beneficial and comfortable to protect the skin from developing pressure and shear damage? Our project will answer these questions and fill these knowledge gaps. Our goal is to better understand how cooling impact the function and comfort of the skin when this is subjected to pressure and shear, and how this varies with age and clinical status. We have designed a series of experiments in both young and older participants, and in those with a spinal cord injury, to answer our research questions. Our first objective is to investigate how different levels of cooling alter the skin' vascular, inflammatory, structural, and perceptual responses to sustained pressure and repeated shear stress. Our second objective is to determine how ageing and the presence of spinal cord injury modulate the skin' physiological and perceptual responses underlying the beneficial effects of cooling on skin tolerance to pressure and shear. Our project will develop new basic knowledge on the role of temperature in reducing the risk of skin damage. This will support innovation in the design of healthcare and user-centred technologies, such as support mattresses, clothing, and medical devices that can control skin temperature. This will unlock the potential of cooling to the skin that will help maintain skin health across the life course.