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The beneficial uses of bacterial toxins in medicine are more and more used lately. For example, Botulinum toxin is a toxic protein produced by the bacterium Clostridium botulinum which has paralytic effects (injection of this toxin into muscle relax specific muscles). Botulinum toxin accomplishes his effects on the neuromuscular junction where he prevents the release of the neurotransmitter acetylcholine (Ach). Utilization of this toxin is in the treatment of various muscle spasms. It is also used in the treatment of migraines. Diphtheria toxin is also one of the toxins used for medical purposes for the treatment of cutaneous and non-Hodgkin T-cell lymphomas. <span>Some bacterial toxins can be used in the treatment of tumours. For example, immunotoxin, which is protein made by fusion of modified antibody and toxin.The antibody binds to an antigen on the target cell, the toxin then enters via endocytosis and kills the cell. Commonly used bacterial toxins in immunotoxins are Diphtheria toxin and the Pseudomonas exotoxin.</span>
Capsid proteins basically "trick" the cell by sticking to receptors on its surface.
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In bone growth, the medullary cavity is enlarged because of the activity of osteoclasts. These are cells working to break down bone, resorbing old bones which will line in the medullary cavity. The cavity is also enlarge as the cells contribute to the increase in length and diameter of a growing bone.