gout is an inflammatory disease in which monosodiumurate crystals deposit into a joint, making it red, hot, tender and swollen within hours. when this happens, it’s called a gouty attack. the underlying cause is hyperuricemia—toomuch uric acid in the blood, which results in the formation of sharp, needle-like crystals,in areas with slow blood flow like the joints and the kidney tubules. over time, repeated gouty attacks can causedestruction of the joint tissue which results in arthritis. to understand where the uric acid comes from,let’s start with purines, which, together with pyrimidines, are nature’s most commonnitrogen-containing heterocycles. a heterocycle being any molecular ring orcycle with different types of atoms. purines, as well as pyrimidines, are key componentsof nucleic acids like dna and rna, and when cells, along with the nucleic acids in thosecells, are broken down throughout the body, those purines are converted into uric acid—amolecule that can be filt...
this animation shows what can happen whensomeone fractures their wrist, and how a fractured wrist is treated. click the navigation arrowsbelow the animation screen to play, pause, rewind or fast-forward the animation. thisanimation contains sound. your body is protected and supported by a framework of bone calledyour skeleton. your bones are very strong. they have three main parts: compact bone onthe outside, spongy bone on the inside and bone marrow, right at the centre. your bonesalso have a nerve and blood supply. the structure of bone makes it very tough. a bone will onlybreak if it's put under a lot of force or twisted awkwardly. a broken bone is said tobe fractured. fractures are painful because bone has a nerve and blood supply. if youtrip, you usually break your fall by outstretching your hands. this puts a lot of pressure onthe wrist bone which may cause it to fracture. here we show the forces that are acting onthe wrist bone when it hits the ground to break your fall....