1. CHOLESTEROL AND ATHEROSCLEROSIS IMAGES

2. Thermogram of a hand Thermal infrared allows us to see thermal energy or radiation – more commonly known as heat. The different colours here represent different levels of thermal energy being emitted from the skin’s surface (and the sleeve’s). The yellow and orange colours show the high thermal energy expected in a hand with healthy blood flow. This imaging technology can show blood flow through various parts of the body and so can be used to find areas of unhealthy blood flow and possible atherosclerosis. CC BY NC Credit: Thermal Vision Research/Wellcome Images CC BY NC BIGPICTUREEDUCATION.COM

3. Pure cholesterol crystal BIGPICTUREEDUCATION.COM Cholesterol is chemically a lipid (or fat), and is transported around the body in the form of high- or low-density lipoproteins (known as HDL and LDL cholesterol). Although cholesterol is important for many of the body’s functions, a high level of LDL cholesterol in the blood can increase the risk of heart disease and strokes. This photograph was produced using a unique lighting effect created by special cross-polarisation filters. CC BY NC Credit: Wellcome ImagesCC BY NC

4. Cholesterol The liver produces around 1–2 grams of cholesterol a day. Cholesterol is necessary to produce vitamin D, steroid hormones and bile acids, as well as being an important component of cell membranes. However, a high level of LDL (low-density lipoprotein) cholesterol in the blood may increase the chance of cardiovascular disease and, hence, premature death. CC BY NC Credit: Wellcome Images CC BY NC

5. Atherosclerotic plaque A photomicrograph showing the lipid deposit of plaque in an artery. This kind of atheromatous plaque will, if unable to heal or left untreated, rupture or continue to build and narrow the artery further, leading to a heart attack or stroke. CC BY NC Credit: Wellcome Images CC BY NC BIGPICTUREEDUCATION.COM

6. Rupture of a plaque Photomicrograph showing the rupture of an atherosclerotic plaque in an artery. Atherosclerotic plaques form because of interactions between cells of the artery wall and leucocytes (white blood cells). CC BY NC Credit: Wellcome Images CC BY NC BIGPICTUREEDUCATION.COM

7. Abdominal aortic aneurysm An abdominal aortic aneurysm is a dangerous condition caused by the weakening of the wall of the large artery that travels down the body from the heart. Once the wall is weakened it is liable to rupture under the influence of factors such as high blood pressure. Measuring aneurysm stress may help to identify patients at risk who could benefit from early surgery to prevent such a disaster. The areas of greatest stress in this silicon model are highlighted in red, and the spots on the image show tiny reflective markers that are part of the measurement technique. People with abdominal aortic aneurysms also often have atherosclerosis (blockage of the arteries by plaques) in their arms and legs, although it’s unclear whether atherosclerosis makes abdominal aortic aneurysm more likely or whether the two simply have common risk factors. CC BY NC Credit: Arindam Choudhuri/Wellcome Images BIGPICTUREEDUCATION.COM

8. Traditional cooked English breakfast Exclusive A cooked breakfast typically includes foods such as sausages, fried eggs, bacon and black pudding. Fried foods like these contain high levels of saturated and trans fats, which, if consumed often, can increase the risk of cardiovascular disease. CC BY NC Credit: Wellcome Images CC BY NC BIGPICTUREEDUCATION.COM

9. Woman taking a statin A woman taking a simvastatin tablet. This is a type of statin, a drug that helps to reduce the levels of LDL (low-density lipoprotein) cholesterol (“bad” cholesterol) and triglycerides (fat) in the blood. Statins also increase the amount of “good” HDL (high-density lipoprotein) cholesterol in the blood. High levels of LDL cholesterol are associated with cardiovascular disease, such as heart attack and stroke. CC BY NC Credit: Libby Welch/Wellcome Images CC BY NC BIGPICTUREEDUCATION.COM

10. Fish oil capsules BIGPICTUREEDUCATION.COM Liver oils found in fish are high in omega-3 fats. These fats can help reduce triglyceride (fat) levels in the blood and so decrease a person’s risk of stroke and heart attacks. CC BY NC Credit: Libby Welch/Wellcome Images CC BY NC

11. Reusing our images Images and illustrations All images, unless otherwise indicated, are from Wellcome Images. Contemporary images are free to use for educational purposes (they have a Creative Commons Attribution, Non-commercial, No derivatives licence). Please make sure you credit them as we have done on the site; the format is ‘Creator’s name, Wellcome Images’.Creative Commons Attribution, Non-commercial, No derivatives licence Historical images have a Creative Commons Attribution 4.0 licence: they’re free to use in any way as long as they’re credited to ‘Wellcome Library, London’.Creative Commons Attribution 4.0 licence Flickr images that we have used have a Creative Commons Attribution 4.0 licence, meaning we – and you – are free to use in any way as long as the original owner is credited.Creative Commons Attribution 4.0 licence Cartoon illustrations are © Glen McBeth. We commission Glen to produce these illustrations for ‘Big Picture’. He is happy for teachers and students to use his illustrations in a classroom setting, but for other uses, permission must be sought. We source other images from photo libraries such as Science Photo Library, Corbis and iStock and will acknowledge in an image’s credit if this is the case. We do not hold the rights to these images, so if you would like to reproduce them, you will need to contact the photo library directly. If you’re unsure about whether you can use or republish a piece of content, just get in touch with us at bigpicture@wellcome.ac.uk.bigpicture@wellcome.ac.uk