keratin


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keratin

 [ker´ah-tin]
a scleroprotein that is the principal constituent of epidermis, hair, nails, horny tissues, and the organic matrix of the enamel of the teeth. Its solution is sometimes used in coating pills when the latter are desired to pass through the stomach unchanged.

ker·a·tin

(ker'ă-tin),
Collective name for a group of proteins that form the intermediate filaments in epithelial cells. Keratins have a molecular weight between 40 kD and 68 kD and are separated one from another by electrophoresis and isoelectric focusing; thus separated, they are sequentially numbered from 1-20, and also subdivided into low, intermediate, and high molecular weight proteins. According to their isoelectric mobility they are either acidic or basic. In general, each acidic keratin protein has its basic equivalent with which it is paired to form the intermediate filaments; some keratin proteins, however, occur unpaired. Various epithelial cells contain different keratin proteins, in a tissue-specific manner. Antibodies to keratin proteins are widely used for histologic typing of tumors, and are especially useful for distinguishing carcinomas from sarcomas, lymphomas, and melanomas.
Synonym(s): ceratin, cytokeratin
[G. keras (kerat-), horn, + -in]

keratin

/ker·a·tin/ (ker´ah-tin) any of a family of scleroproteins that are the main constituents of epidermis, hair, nails, and horny tissues. The high-sulfur keratin polypeptides of ectodermally derived structures, e.g., hair and nails, are also called hard k's.

keratin

(kĕr′ə-tĭn)
n.
1. Any of a class of filamentous proteins that are abundant in the cytoskeleton of vertebrate epithelial cells and are the main constituents of the outer layer of skin and tough epidermal structures such as hair, nails, hooves, feathers, and claws.
2. Material composed principally of keratin proteins.

ke·rat′i·nous (kə-răt′n-əs) adj.

keratin

[ker′ətin]
Etymology: Gk, keras, horn
a fibrous sulfur-containing protein that is the primary component of the epidermis, hair, nails, enamel of the teeth, and horny tissue of animals. The protein is insoluble in most solvents, including gastric juice. For this reason, it is often used as a coating for pills that must pass through the stomach unchanged to be dissolved in the intestines.

ker·a·tin

(ker'ă-tin)
A scleroprotein or albuminoid present in hair and nails; it contains a relatively large amount of sulfur, is insoluble in gastric juice, and is sometimes used for coating tablets that are intended to be dissolved only in the intestine.
Synonym(s): cytokeratin.
[G. keras (kerat-), horn, + -in]

keratin

A hard protein (scleroprotein) of cylindrical, helical molecular form occurring in horny tissue such as hair and nails and in the outer layers of the skin. Hair and nails consist almost wholly of keratin. Keratins are insoluble and cannot generally be split by PROTEOLYTIC enzymes.

keratin

a hard, fibrous, sulphur-containing protein with an alpha-helix structure, found in the epidermis of vertebrates, mainly in the outermost layers of skin. Keratin can have several forms: in scales, feathers, hooves, horns, claws and nails it is hard, while wool and hair are made up of a soft and flexible form.

Keratin

A tough, nonwater-soluble protein found in the nails, hair, and the outermost layer of skin. Human hair is made up largely of keratin.

keratin

sulphur-containing, insoluble scleroprotein, forming stratum corneum, nail plate and hair shaft, from enzymic conversion of epidermal cells

ker·a·tin

(ker'ă-tin)
Collective name for a group of proteins that form intermediate filaments in epithelial cells. Keratins have a molecular weight of 40-68 kD and are either acidic or basic. Antibodies to keratin proteins are widely used for histologic typing of tumors and are especially useful for distinguishing carcinomas from sarcomas, lymphomas, and melanomas.
[G. keras (kerat-), horn, + -in]

keratin (ker´ətin),

n. an insoluble sulfur-containing protein with a high content of the amino acids tyrosine and leucine; the main component of epidermis, hair, nails, keratinized epithelium. It contains a relatively large amount of sulfur, is insoluble in the gastric juices, and is sometimes used for coating enteric pills that are intended to be dissolved only in the intestine.
keratin layer,
n the outer layer of cells of the epidermis, which contain a tough, fibrous protein (keratin). This layer acts as a protective barrier against outside elements.

keratin

a scleroprotein which is the principal constituent of epidermis, hair, nails, horny tissues, and the organic matrix of the enamel of the teeth. Its solution is sometimes used in coating pills when the latter are desired to pass through the stomach unchanged.

keratin cyst
see horn cyst.
keratin pearl
see horn pearls.
keratin tag
see fibrovascular papilloma.

Patient discussion about keratin

Q. skins does excrete oil and keratin what exactly is the whitish cape up that you can squeeze out from underskin

A. It sounds like you refer to sebum, an oily substance secreted by (how surprising :) ) sebaceus glands attached to the hair root. It's important for the skin, although abnormal secretion of it may cause diseases such as acne.

You may read more here:
http://en.wikipedia.org/wiki/Sebum#Sebum

More discussions about keratin
References in periodicals archive ?
In case of PVA/Keratin nanofibrous scaffold as crude keratin was blended with PVA it showed some beads formation.
Hemostratic properties and the role of cell receptor recognition in human hair keratin protein hydrogels.
The researchers noted that further research could reveal numerous different keratin fragments in the body's innate defense system.
The ratios of keratin and sugar using for preparation of blend films shown in Table 1.
Unlike scheduled medicines, cosmetics entering the market do not have to undergo routine testing; however, owing to health concerns, the keratin treatments have come under much international scrutiny.
Milia en plak (MEP) daha cok orta-ileri yas kadinlarda, basboyun bolgesinde eritemli zemin uzerinde gelisen keratin kistleri ile karakterize cok nadir inflamatuvar bir milia varyantidir.
Streptococcal M protein contains a number of amino acid sequences also found in keratins that are upregulated in psoriatic lesions.
Win a Keratin Complex Smoothing Therapy treatment WELL-ESTABLISHED and highly recommended for quality hairdressing, Christopher Boyton continues to welcome new clients every week - why not become their next keratin complex client by winning a complimentary Smoothing Therapy treatment, follow-up blow dry and free Keratin products (total value up to pounds 200).
It eliminates up to 95 per cent of frizz and leaves the hair soft, shiny and luxurious, by infusing a special blend of natural keratin deep into the damaged cuticle.
Harlequin-type ichthyosis is a skin disease, the most severe form of congenital ichthyosis, characterized by a thickening of the keratin layer in fetal human skin.
The bacterial flora capable of growing on tryptic soy agar and sampled from unaffected tortoises consisted of five species, three of which are likely to be capable of degrading keratin.
3]) transformed UROtsa cells grown on serum-containing growth medium and the derived heterotransplants all overexpressed keratin 6a mRNA and protein compared to parental UROtsa cells grown in serumcontaining growth medium.