Callus (redirected from callus pyoderma)

callus: see corns and calluses.

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callus

In botany, soft tissue that forms over a wounded or cut plant surface, leading to healing. A callus arises from cells of the cambium. When a callus forms, some of its cells may organize into growing points, some of which in turn give rise to roots while others produce stems and leaves. Thus a callus may be capable of regenerating an entire plant.

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callus

1. an area of skin that is hard or thick, esp on the palm of the hand or sole of the foot, as from continual friction or pressure

2. an area of bony tissue formed during the healing of a fractured bone

3. Botany

a. a mass of hard protective tissue produced in woody plants at the site of an injury

b. an accumulation of callose in the sieve tubes

4. Biotechnology a mass of undifferentiated cells produced as the first stage in tissue culture

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callus [′kal·əs]

(botany)

A thickened callose deposit on sieve plates.

A hard tissue that forms over a damaged plant surface.

(medicine)

Hard, thick area on the surface of the skin.

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Callus 

(1) Tissue formed in plants on the surface of a wound (cracks, taps, the bases of cuttings, and areas of concrescence of stock and scion). A callus promotes the healing of wounds. Consisting of thin-walled parenchymal cells, a callus develops when there is cell division of any living tissue of the plant (cambium or phloem) in the peripheral zone of the pith, lying next to the protoxylem. Adventitious roots and buds, particularly with grafting, often develop in the callus. (2) Corpus callosum, an accumulation of callóse that obstructs the sieve plate when the sieve tubes of the phloem age. Use of the term in this sense is obsolete.

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Callus 

a thickening of the horny layer of skin as a result of constant pressure or friction. Calluses usually appear on the palms, soles, and other parts of the body that are in constant contact with tough surfaces. The cracks formed on the surface of a callus may hinder one’s ability to work, and they can also be portals of entry for pyogenic microbes, resulting in such conditions as erysipelatous inflammations and phlegmons.