Stress, biological effects

We have already stressed the potential importance of lipid-rich membranes in the skin as potential targets for ROS-induced damage and ageing of human skin is morphologically identical to changes found by peroxidative processes (Serri et al., 1977). The involvement of AA metabolites in skin disease, and in particular psoriasis, has been the subject of much recent interest. Studies have included topical and intradermal administrations of AA metabolites, and assay of such products in clinical specimens. Results show that concentration of AA, 12-hydroxy-eicosatetraenoic acid (12-HETE), PG and leu-kotrienes are increased in psoriatic lesions (Hammarstrom etal., 1975 Camp etal., 1983 Brain etal., 1984 Duell et al., 1988) and also that full-thickness epidermis from normal and diseased skin has the enzymatic capacity to convert AA to some of the same metabolites (Hammarstrom etal., 1975, 1979 Camp etal., 1983 Brain etal., 1984 Ziboh et al., 1984 DueU et al., 1988). The biological effect of both 12-HETE and leukotrienes was confirmed by both topical application and intradermal injection, which caused epidermal inflammation and... 

Variation of the content of impurities in the different CNT preparations [21] offers additional challenges in the accurate and consistent assessment of CNT toxicity. As-produced CNTs generally contain high amounts of catalytic metal particles, such as iron and nickel, used as precursors in their synthesis. The cytotoxicity of high concentrations of these metals is well known [35, 36], mainly due to oxidative stress and induction of inflammatory processes generated by catalytic reactions at the metal particle surface [37]. Another very important contaminant is amorphous carbon, which exhibits comparable biological effects to carbon black or relevant ambient air particles. 

In terms of anthropogenic stress (the effect of human activity on other organisms), there is a need for the identification and evaluation of the potential impacts of proposed projects, plans, programs, policies, or legislative actions on the physical-chemical, biological, culmral, and socioeconomic components of the... 

Collins, A.R., Assays for oxidative stress and antioxidant status applications to research into the biological effectiveness of polyphenols. Am. J. Clin. Nutr., 81, 261S, 2005. 

Multiple factors determine patterns of tobacco use among racial and ethnic minority groups in the United States socioeconomic status, cultural characteristics, degree of assimilation into American culture, stress, biological elements, targeted advertising, price of tobacco products, and the varying capacity of communities to mount effective tobacco control initiatives. 

Air pollution, exercise, and heat stress. Arch. Environ. Health 28(4) 177—181. Eckardt, R.E., N.H.McFarland, Y.C.Alarie, and W.M.Busey. 1972. The biologic effect from longterm exposure of primates to carbon monoxide. Arch. Environ. Health 25(6) 381—387. Ehrich, W.E., S.Bellet, and F.H.Lewey. 1944. Cardiac changes from CO poisoning. Am. J. Med. Scd. 208 511-523. 

Change in the cellular redox environment can lead to several biological effects ranging from altered signal transduction pathways, gene expression, mutagenesis and cell death (apoptosis). Oxidative stress has now been implicated in many diseases such as atherosclerosis, Parkinson s disease, Alzheimer s disease, cancer, etc. For the protection of cells from oxidative stress, supplementation with exogenous antioxidants becomes necessary. 

Acid stress is defined as a combined biological effect of low pH and organic acids present in an environment to which an organism may be exposed (Barua et al., 2002). Various terms have evolved to describe a response following exposure to acid stress (1) acid adaptation, (2) acid... 

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