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Ageing premature

Ash content (DIN 52 005). Unwanted presence of inorganic impurities due to incorrect filtration of neutralization residues and rust contaminants is undesirable because may contribute to premature ageing. Ash determination provides some interesting information. In general, most resins have ash content lower than 0.1%. [Pg.616]

False. You may just look foolish and sad. However, long-term smoking can prematurely age your skin. [Pg.125]

As public consciousness of the harmful effects of exposure to ultraviolet light (skin cancer, premature ageing, etc.) has increased, there has been a substantial increase in the use of sunscreens. These sunscreens have, however, been associated with a number of reported problems such as phototoxicity and photoallergy. The use of p-aminobenzoic acid (PABA) and its derivatives has been discontinued due to their ability to... [Pg.219]

Ultraviolet radiation Invisible rays that are part of the energy that comes from the sun. UV radiation can damage the skin and cause melanoma and other types of skin cancer. UV radiation that reaches the earth s surface is made up of two types of rays, called UVA and UVB rays. UVB rays are more likely than UVA rays to cause sunburn, but UVA rays pass deeper into the skin. Scientists have long thought that UVB radiation can cause melanoma and other types of skin cancer. They now think that UVA radiation also may add to skin damage that can lead to skin cancer and cause premature aging. For this reason, skin specialists recommend that people use sunscreens that reflect, absorb, or scatter both kinds of UV radiation. [NIH]... [Pg.77]

Cells of patients with Bloom syndrome (BS) have many chromosome breaks and a high frequency of sister chromatid exchanges, perhaps in an effort to correct these breaks. The body is small but well-proportioned.kk A somewhat similar disease, the Werner syndrome (WS), is associated with premature aging.11 The Bloom s protein BLM and the WS gene product WRN are both helicases related to E.coli RecQ. Protein BLM colocalizes with replication protein A as discrete foci in the meiotic synaptonemal complex.1 3 Protein WRN also seems to be associated with DNA replication. Defects... [Pg.1585]

The early diagnosis of diseases, the study of premature aging, the determination of the biomolecular mechanisms taking place and the... [Pg.168]

Skin constitutes the interface between the human body and the environment. It represents a major target of oxidative stress since it is exposed to external oxidant aggressions like UV radiation, ozone, chemicals or pollution. Continuous exposure to such damaging effects and/or deficiency of the antioxidant protection systems result in skin premature aging and contribute to the development of cutaneous diseases and cancers [23]. Electrochemical studies dealing with the effect... [Pg.169]

Recent progress in the details of the metabolism of HA has also clarified the long appreciated observations that chronic inflammation, and sun damage caused by ultraviolet light cause premature aging of skin. These processes as well as normal aging, all utilize similar mechanisms that cause loss of moisture and changes in HA distribution. [Pg.246]

Chronic inflammation causes premature aging of the skin, as observed in patients with atopic dermatitis. The constant inflammatory process leads to decreased function of the skin barrier, accompanied by loss of skin moisture. Presumably, the skin of such patients contains decreased levels of HA. Alternatively, the HA may reflect that found in chronological aging, with a change in the ability to take on water of hydration with enhanced association with tissue structures and loss of extractabil-ity. Demonstration of such changes and the precise histolocalization of this decreased HA deposition would be of intrinsic interest, a study that has not been performed yet. [Pg.257]

The acute inflammatory process is associated initially with increased HA levels, the result of the cytokines released by the polymorphonuclear leukocytes, the predominant cells of the acute inflammatory process. The erythema, swelling, and warmth of the acute process are followed later by the characteristic dry appearance and the formation of wrinkles. The precise mechanisms are unknown, but may relate to the differences between acute and chronic inflammatory cells and the attendant chemical mediators released by such cells. Alternatively, initiation of a wound healing response, with collagen deposition, may be a mechanism invoked for the premature aged appearance of the skin in chronic inflammation. [Pg.257]

The ozone layer around the Earth has provided us all a natural ring of protection from harmful UV radiation. However, multiple anthropogenic activities have acted as barriers and often caused damage to this shield. Less protection from UV light will, over time, lead to increased health problems and crop damage. Major health problems linked to overexposure to UV radiation by the depletion of ozone include skin cancer (melanoma and nonmelanoma), premature aging of the skin and other skin problems, cataracts and other eye damage, and suppression of normal immune system function.29... [Pg.13]

Puerto, M., Guayerbas, N., Victor, V.M., and De la Fuente, M. 2002. Effects of the N-acetylcysteine on macrophage and lymphocyte functions in a mouse model of premature ageing. Pharmacol Biochem Behav 73 797-804. [Pg.65]


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