In adults, eczema occurs most frequently on the hands and elbows, and in bending areas such as the inside of the elbows and back of the knees. In young children, eczema is often seen on the elbows, knees, face, neck, and scalp. Signs and symptoms of atopic eczema include: 1  Itchiness. 2  Skin redness.
Sphingolipids are composed of a backbone of sphingosine which is derived itself from glycerol. Sphingosine is N-acetylated by a variety of fatty acids generating a family of molecules referred to as ceramides. Sphingolipids predominate in the myelin sheath of nerve fibers.
Acting on a membrane phospholipid, phospholipase C cleaves off IP3, which is a small polar molecule. Remaining in the membrane is the DAG, which consists of glycerol and two fatty acids. The IP3 diffuses to the endoplasmic reticulum, which stores Ca ++ .The IP3 binds to and opens a ligand gated ion channel that allows Ca ++ to move out into the cytosol, where the Ca ++ activates various cellular processes.emaining in the membrane is the DAG, which consists of glycerol and two fatty acids. The IP3 diffuses to the endoplasmic reticulum, which stores Ca ++ . The IP3 binds to and opens a ligand gated ion channel that allows Ca ++ to move out into the cytosol, where the Ca ++ activates various cellular processes.