wrinkles

Print problem caused by a crushed or irregular paper surface that can ruin the print product. Wrinkles can be caused by many factors, including moisture damage, sloppy packing or handling, or incorrect paper feed to the printer.

Wrinkles are folds and creases in the skin. In ageing skin, the normal process of proliferation and organization of skin cells breaks down, the skin thins, and the tidy columns of cells characterizing the young, healthy epidermis (outer skin) become disarrayed. Collagen fibres, which are found in the dermis and which help to maintain the integrity of the skin, decrease in density, number, and organization, while the smooth and ribbon-like elastin fibres, which are also found in the dermis and which enable the skin to regain its normal shape after stretching, become coarser, denser, and less resilient.

Wrinkles have intrinsic and extrinsic causes. The intrinsic cause is a genetically-programmed senescence in which the skin reaches a point when membrane receptors in the cells no longer respond to growth factors stimulating DNA replication and cell division. Thus, with age, skin cells lose their ability to proliferate, and generation time lengthens. There is no way to prevent these developments. Extrinsic causes include exposure to smoking and sunlight. Premature wrinkling increases with cigarette consumption. UVB light damages amino acids (the building blocks of the proteins, enzymes, and nucleic acids), affects various kinds of skin cells, and can cause any single cell to become a high-energy ‘singlet’ which releases energy that may break chemical bonds, initiating skin damage within 3 minutes of exposure of previously unexposed skin. Sun screens and the general avoidance of sunlight help to prevent photo-ageing.

People have considered wrinkles highly undesirable for millennia. An ancient Egyptian treatment for wrinkles was a mixture of incense, wax, olive oil, cyperus, and milk, applied for 6 days. A 1713 recipe book advised a distillation of a blend of the flowers of elder, Fleur-de-lis, mallows, and beans, added to the pulp of melon, honey, and the white of eggs, to remove wrinkles, Not so safe were treatments such as an arsenic complexion wafer and an arsenic soap to treat skin blemishes, wrinkles, and sallow skin, advertised in Vogue in 1908. It is doubtful that any of these treatments had lasting success — so women, and sometimes men, resorted to cosmetics. In the sixteenth, seventeenth, and eighteenth centuries in particular, some women concealed wrinkles with thick paint that often contained poisonous substances such as mercury and white lead.

Modern treatments for wrinkles range from alpha-hydroxy-acid creams, which promote the shedding of the outer skin layer, to surgical face lifts, which smooth wrinkles through tightening and removing excess skin. One promising skin application is retinoic acid, a synthetic derivative of vitamin A, which reduces fine wrinkles, sloughs off outer layers, and causes collagen to reaccumulate, thickening the moisture-conserving skin fibres. Though collagen molecules in creams are too large to be absorbed, collagen may be injected into the skin to smooth wrinkles.

— Kristen L. Zacharias

Bibliography

• Corson, R. (1972). Fashions in makeup from ancient to modern times. Universe Books, New York

See also ageing; skin; sun and the body.