1.
Clinical Application of Plant Sterol and Stanol Products.
Cofán, M, Ros, E
Journal of AOAC International. 2015;(3):701-706
Abstract
Plant sterols and stanols (PS) are natural, non-nutritive compounds that play important structural roles in plant membranes and abound in seeds and oils derived from them. Because they act within the intestinal lumen and undergo minimal absorption into the enterocytes, PS are non-systemic agents. Their physiological role in plants, natural origin, and non-systemic action, together with their proven capacity to lower serum total and LDL-cholesterol, make them quite attractive as non-pharmacological agents for the treatment of hypercholesterolemia. Recent meta-analyses have summarized the results of >100 randomized clinical trials and have clearly established that LDL-cholesterol is reduced by 9-12% with consumption of PS-fortified foods in different formats at doses of 2-3 g per day. PS are effective and safe cholesterol-lowering agents with many clinical applications: adjuncts to a healthy diet, common hypercholesterolemia, combination treatment with statins, metabolic syndrome, and diabetes. The cholesterol-lowering efficacy appears to be similar in all clinical situations. PS are also ideal agents to treat hypercholesterolemic children who are still not candidates to statin therapy or receive only low-dose statins. In the setting of statin treatment, the expected LDL-cholesterol reduction with PS is equivalent to up titrating twice the statin dose. There is not enough information on the efficacy of PS as add-on therapy to ezetimibe, fibrates, or bile acid binding resins. Attesting to the consistent scientific evidence on the cholesterol-lowering efficacy and safety of functional foods supplemented with PS, several national and international clinical societies have endorsed their use as adjuncts to a healthy diet.
2.
Functional electron microscopy in studies of plant response and adaptation to anaerobic stress.
Vartapetian, BB, Andreeva, IN, Generozova, IP, Polyakova, LI, Maslova, IP, Dolgikh, YI, Stepanova, AY
Annals of botany. 2003;(2):155-72
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Abstract
This article reviews the contribution made by functional electron microscopy towards identifying and understanding the reactions of plant roots and shoots to anaerobic stress. Topics examined include: (1) unexpected hypersensitivity, rather than hyper-resistance, to anoxia of root tips of flooding-tolerant plants; (2) protective, rather than damaging, effects of a stimulated energy metabolism (glycolysis and fermentation) under anaerobic conditions; (3) the concept of two main strategies of plant adaptation to anaerobic environments, namely avoidance of anaerobiosis on the whole plant level, termed 'apparent' tolerance, and metabolic adaptation at the cellular and molecular levels, termed 'true' tolerance; (4) the importance of protein synthesis during hypoxia and anoxia for enhanced energy production and metabolic adaptation; (5) a general adaptive syndrome in plants to stress at the ultrastructural level and a possible molecular mechanism for its realization under anoxia; (6) the physiological role of anaerobically synthesized lipids and nitrate as alternative electron acceptors in an oxygen-free medium; and (7) the selection of cell lines derived from callus cultures that possess enhanced tolerance to anoxia and can regenerate whole plants with improved tolerance of soil waterlogging.