The term is used to describe the condition of oxidative damage resulting when the critical balance between free radical generation and antioxidant defenses is unfavorable. These compounds induce endothelial cell injury and produce changes in the arterial walls. Studies on atherosclerosis reveal the probability that the disease may be due to free radical reactions involving diet-derived lipids in the arterial wall and serum to yield peroxides and other substances. The highly significant correlation between consumption of fats and oils and death rates from leukemia and malignant neoplasia of the breast, ovaries, and rectum among persons over 55 years may be a reflection of greater lipid peroxidation. It is possible that endogenous free radical reactions, like those initiated by ionizing radiation, may result in tumor formation. Cancer initiation and promotion is associated with chromosomal defects and oncogene activation. Cancer and atherosclerosis, two major causes of death, are salient “free radical” diseases. These are manifested as diseases at certain ages determined by genetic and environmental factors. However, superimposed on this common pattern are patterns influenced by genetics and environmental differences that modulate free radical damage. Such “normal” changes with age are relatively common to all. Among them, lipids, nucleic acids, and proteins are the major targets.įree radical reactions are expected to produce progressive adverse changes that accumulate with age throughout the body. Targets of free radicals include all kinds of molecules in the body. Free radicals attack important macromolecules leading to cell damage and homeostatic disruption. These are highly reactive species, capable in the nucleus, and in the membranes of cells of damaging biologically relevant molecules such as DNA, proteins, carbohydrates, and lipids. The most important oxygen-containing free radicals in many disease states are hydroxyl radical, superoxide anion radical, hydrogen peroxide, oxygen singlet, hypochlorite, nitric oxide radical, and peroxynitrite radical. They can either donate an electron to or accept an electron from other molecules, therefore behaving as oxidants or reductants. Many radicals are unstable and highly reactive. The presence of an unpaired electron results in certain common properties that are shared by most radicals. The present review provides a brief overview on oxidative stress mediated cellular damages and role of dietary antioxidants as functional foods in the management of human diseases.Ī free radical can be defined as any molecular species capable of independent existence that contains an unpaired electron in an atomic orbital. Thus, the search for effective, nontoxic natural compounds with antioxidative activity has been intensified in recent years. Synthetic antioxidants such as butylated hydroxytoluene and butylated hydroxyanisole have recently been reported to be dangerous for human health. Hence application of external source of antioxidants can assist in coping this oxidative stress. Free radicals thus adversely alter lipids, proteins, and DNA and trigger a number of human diseases. If free radicals overwhelm the body's ability to regulate them, a condition known as oxidative stress ensues. A balance between free radicals and antioxidants is necessary for proper physiological function. Free radicals reactive oxygen species and reactive nitrogen species are generated by our body by various endogenous systems, exposure to different physiochemical conditions or pathological states. Then draw a line off the "spine" of the diagram for each factor, and label each line.In recent years, there has been a great deal of attention toward the field of free radical chemistry. As a starting point, you can use models such as the McKinsey 7S Framework (which offers you Strategy, Structure, Systems, Shared values, Skills, Style and Staff as factors that you can consider) or the 4Ps of Marketing (which offers Product, Place, Price, and Promotion as possible factors).īrainstorm any other factors that may affect the situation. Try to draw out as many of these as possible. These may be systems, equipment, materials, external forces, people involved with the problem, and so on. Next, identify the factors that may be part of the problem. Step 2: Work Out the Major Factors Involved CATWOE can help you do this – this asks you to look at the problem from the perspective of Customers, Actors in the process, the Transformation process, the overall World view, the process Owner, and Environmental constraints.īy considering all of these, you can develop a comprehensive understanding of the problem. It's important to define your problem correctly. Use whichever approach you feel most comfortable with. Some people prefer to write the problem on the right-hand side of the piece of paper, and develop ideas in the space to the left.
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