Stress-induced aging

Factors other than the stress induced ageing also play an important role in cable failure. Thorough investigation (7, 8) has revealed that imperfections present in the cable are responsible for premature failures and also indirectly for the gradual deterioration. 

Blake, M.J., Udelsman, R., Feulner, G.J., Norton, D.D., Holbrook, N.J. (1991). Stress induced heat shock protein 70 expression in adrenal cortex An ACTH-sensitive. age-dependent response. Proc. Natl. Acad. Sci. USA 88, 9873-9877,... 

Cutler, R. G., Kelly, J., Storie, K. et al. Involvement of oxidative stress-induced abnormalities in ceramide and cholesterol metabolism in brain aging and Alzheimer s disease. Proc. Natl Acad. Sci. U.S.A. 101 2070-2075,2004. 

Yamamoto, K. et al., Plasminogen activator inhibitor-1 is a major stress-regulated gene Implications for stress-induced thrombosis in aged individuals, Proc. Nat. Acad. Sci., 99, 890, 2002. 

Taken together, these studies indicate that EGb is able to modulate both stress-induced and age-related behavioral sensitization by regulating alterations of the neuroendocrine system. 

The turnover rates of GSH and the activity of GSH synthetase during oxidative stress induced by butylhydroperoxide in young and mature animals have been measured. These studies have found that defense mechanisms against oxidative stress in the brain differ with age. Young people can increase the cellular availability of GSH, whereas older people can increase GSH synthetase activity during oxidative stress. These differences make older people more susceptible to brain oxidative damage. 

Liang, F.Q., and Godley, B.F. Oxidative stress-induced mitochondrial DNA damage in human retinal pigment epithelial cells A possible mechanism for RPE aging and age-related macular degeneration, Exp. Eye Res., 76,397-403, 2003. 

Aging-resistance. Aging-resistance specifically describes the capacity of materials to resist critical stress-induced cracking. The majority of plastics or elastomers are lacking in aging-resistance, except for biomedical-grade poly (ether urethanes) and their derivative products. 

It has also been shown in several studies that the combination of stress, temperature, and moisture can accelerate the hydrolytic instability of certain epoxy adhesives. In an FTIR study of the effect of moisture on DGEBA epoxy cured with nadic methyl anhydride, spectra changes were observed in stressed specimens aged for 155 days at 80°C and 100 percent RH.47 This was attributed to the slow, stress-induced hydrolysis of ester groups. In another study,... 

F19. Fu, S., Fu, M. X., Baynes, J. W., Thorpe, S. R., and Dean, R. T., Presence of dopa and amino acid hydroperoxides in proteins modified with advanced glycation end products (AGEs) Amino acid oxidation products as a possible source of oxidative stress induced by AGE proteins. Biochem. J. 330, 233-239 (1998). 

Experiments on the stress-chemllumlnescence (SCL) behavior of TGDDM/DDS epoxy and nylon 66 specimens were performed under various conditions to determine the potential of the technique to measure stress-induced and stress-accelerated aging processes. Representative results of typical SCL experiments with epoxy specimens are shown In Figures 2 and 3 where emitted light (photon counts/s) Is plotted as a function of time and stress. In both... 

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