Biomaterial Database

Thickened patches of stratum corneum on the human tympanic membrane. 1986

J M Weinberger, and M Hawke

If sufficient illumination is used, discrete thickened patches of keratin can be seen on the lateral surface of the tympanic membrane. These thickened areas which consist of numerous keratinocytes are separated by valleys lined by only one to three layers of keratinocytes. Keratin patches consistently appear as linear and discontinuous white streaks arranged along geodesic lines. There is a small area we have termed the "slow zone", located anterior and inferior to the umbo, that has comparatively fewer patches and where ink dots can remain static for several weeks. This paper describes the histology and distribution of keratin patches and postulates a mechanism for their formation, based upon the movement of the superficial layer of corneocytes towards the annulus.

UI	MeSH Term	Description	Entries
D007633	Keratins	A class of fibrous proteins or scleroproteins that represents the principal constituent of EPIDERMIS; HAIR; NAILS; horny tissues, and the organic matrix of tooth ENAMEL. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms a coiled-coil alpha helical structure consisting of TYPE I KERATIN and a TYPE II KERATIN, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure. alpha-Keratins have been classified into at least 20 subtypes. In addition multiple isoforms of subtypes have been found which may be due to GENE DUPLICATION.	Cytokeratin,Keratin Associated Protein,Keratin,Keratin-Associated Proteins,alpha-Keratin,Associated Protein, Keratin,Keratin Associated Proteins,Protein, Keratin Associated,alpha Keratin
D008953	Models, Anatomic	Three-dimensional representation to show anatomic structures. Models may be used in place of intact animals or organisms for teaching, practice, and study.	Anatomic Models,Models, Surgical,Moulages,Models, Anatomical,Anatomic Model,Anatomical Model,Anatomical Models,Model, Anatomic,Model, Anatomical,Model, Surgical,Moulage,Surgical Model,Surgical Models
D002465	Cell Movement	The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.	Cell Migration,Locomotion, Cell,Migration, Cell,Motility, Cell,Movement, Cell,Cell Locomotion,Cell Motility,Cell Movements,Movements, Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014432	Tympanic Membrane	An oval semitransparent membrane separating the external EAR CANAL from the tympanic cavity (EAR, MIDDLE). It contains three layers: the skin of the external ear canal; the core of radially and circularly arranged collagen fibers; and the MUCOSA of the middle ear.	Eardrum,Eardrums,Membrane, Tympanic,Membranes, Tympanic,Tympanic Membranes