Stress Responses across the Scales of Life: Toward a Universal Theory of Biological Stress.

Although biological systems are more complex and can actively respond to their environment, an effective entry point to the development of a universal theory of biological stress is the physical concepts of stress and strain. If you apply stress to the end of a beam of steel, the strain will accumulate within that steel beam. If the stress is weak then the strain will disappear when the force is removed and the beam will return to its original state of form and functionality.

Differential sensitivity of oligodendrocytes and motor neurons to reactive nitrogen species: implications for multiple sclerosis.

Depending on its concentration, nitric oxide (NO) has beneficial or toxic effects. In pathological conditions, NO reacts with superoxide to form peroxynitrite, which nitrates proteins forming nitrotyrosine residues (3NY), leading to loss of protein function, perturbation of signal transduction, and cell death. 3NY immunoreactivity is present in many CNS diseases, particularly multiple sclerosis.