Bursin is a peptide that can be isolated from the bursa of Fabricius of chicken. Bursin induces the phenotypic differentiation of mammalian and avian B precursor cells. Bursin also increases cyclic guanosine monophosphate in cells of the human B-cell line Daudi, its derivatives are able to protect against infection by amplifying the immune response induced by H9N2.

Dihydrorhodamine 123 is a fluorescent probe.

Methylsuccinic acid is a normal metabolite found in human fluids. Increased urinary levels of Methylsuccinic acid (together with ethylmalonic acid) are the main biochemical measurable features in ethylmalonic encephalopathy a rare metabolic disorder with an autosomal recessive mode of inheritance that is clinically characterized by neuromotor delay hyperlactic acidemia recurrent petechiae orthostatic acrocyanosis and chronic diarrhea.