Tylosis


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Related to Tylosis: tylosis palmaris et plantaris

Tylosis

 

a blister-like protrusion of xylem parenchymal cells that obstruct the vessels or, less commonly, the tracheids. Tyloses form when the closing membrane of a pit grows into the lumen of a vessel. The cytoplasm and, sometimes, the nucleus of the cell move into the protrusion, which is not separated by a septum from the mother cell. Tyloses may be filled with starch, calcium salts, resin, or gum. Although they are most characteristic of woody plants, they also occur in herbaceous plants, such as pumpkin, purslane, and dock. Tyloses lower the water-retaining capacity of the heartwood and increase resistance to rotting and penetration by fungi. The formation of tyloses is sometimes a response to injury.

References in periodicals archive ?
I went to a chiropodist who referred me to a skin doctor and they said it was tylosis.I'd never heard of it.''
Because Janet, a medical secretary, also has tylosis there is a strong chance that she too will develop cancer of the oesophagus in later life.
Prof Field said: ``We have discovered that one of the genes is not working properly in the oesophagus of family members who have the skin disorder, tylosis.
Tylosis oesophageal cancer only runs in families and does not target everyone with thick skin on their hands and feet.
The scientists looked at three related families affected by tylosis.
Last night, she said: "I will do anything that stops my family from being at risk from tylosis and cancer of the oesophagus.
"Two of my four children have tylosis and so does my granddaughter and I am desperately hoping they do not develop the cancer.
Scientists looked at three families in total affected by tylosis which causes excessive thickening of the skin on the palms and soles.
The experts believe the gene responsible for causing the cancer within tylosis sufferers is most likely to be the same gene that causes sporadic oesophageal cancers that occur by chance.
Tylosis Palmaris et Plantaris (Howel Evans syndrome) describes a familial association of punctuate keratosis of the palms and soles with esophageal carcinoma.
The condition is linked to tylosis, a mild skin disorder which causes hard, yellow skin on the feet and hands.
"Seventeen people on my father's side died of this and now my daughter and nineyear-old granddaughter have got Tylosis, so I do worry about them.