...sequencing of the genes that encode transporters and channels (as well as their subunits) is not a trivial matter and must be complemented by experiments determining expression patterns. The Xenopus oocytes that have been used for such studies are transfected cells rather than “real” polarized cells of the thick ascending limb of the loop of Henle surrounded by the sophisticated hypertonic environment of the renal medulla. The complex polyuria–polydipsia syndrome described by Schlingmann et al. is attributable to the concomitant loss-of-function mutations in both CLCNKA and CLCNKB; the syndrome results in ion selectivity, demonstrating the means whereby a renal tubular cell lets one type of ion (chloride) through the lipid membrane to the exclusion of others. It thus provides yet another example of the molecular basis of Bartter’s syndrome (see Figure). The contributions of Roderick McKinnon and Peter Agre to solving these two complementary problems of the resorption of renal solute and renal solvent earned them the 2003 Nobel Prize in chemistry.5 We live in a fascinating time in which clinical syndromes can be deciphered at the molecular and even the atomic level. From the Department of Medicine and the Membrane Protein Study Group, University of Montreal (D.G.B.); and the Department of Human Genetics and Medicine, McGill University (T.M.F.) — both in Montreal. 1. Peters M, Jeck N, Reinalter S, et al. Clinical presentation of genetically defined patients...
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...Lipoic acid, or more technically alpha-lipoic acid, is an increasingly recognized dietary supplement that has demonstrated a variety of beneficial effects. Lipoic acid occurs naturally in small amounts in the body where it is involved in a variety of processes but is primarily important in aerobic metabolism and various enzymatic actions. Lipoic acid is known to be involved in the energy-producing processes in cells. Lipoic acid is found in many foods, including liver, kidney, and heart meat and in broccoli, spinach, beets, yeast, yams, carrots, and potatoes. Scientists discovered lipoic acid in the 1950s, but the importance of this compound and its critical role as an antioxidant in the body was not defined until 1988. Lipoic acid is readily converted in the body to another compound called dihydrolipoic acid. Dihydrolipoic acid, or R-Dihydrolipoic acid, is the reduced form of lipoic acid that has more immediate effects than lipoic acid and has even more significant antioxidant effects than lipoic acid. Both of these antioxidants are particularly effective in destroying free radicals known as peroxynitrite radicals. These damaging compounds contain both oxygen and nitrogen and have been implicated in the development of chronic inflammation, nervous system diseases, pulmonary diseases, and arteriosclerosis. Lipoic acid acts as an antioxidant in the body and has been shown to have protective effects against nerve damage in diabetics, among other beneficial effects. Lipoic acid...
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...Chronic kidney diseaseFrom Wikipedia, the free encyclopedia Jump to: navigation, search Chronic kidney disease Classification and external resources Uremic frost on the forehead and scalp of a young man who presented with complaints of chronic anorexia and fatigue with blood urea nitrogen and serum creatinine levels of approximately 100 and 50 mg/dL respectively. ICD-10 N18 ICD-9 585.9 585.1-585.5 403 DiseasesDB 11288 MedlinePlus 000471 eMedicine article/238798 MeSH D007676 Chronic kidney disease (CKD), also known as chronic renal disease (CRD), is a progressive loss in renal function over a period of months or years. The symptoms of worsening kidney function are non-specific, and might include feeling generally unwell and experiencing a reduced appetite. Often, chronic kidney disease is diagnosed as a result of screening of people known to be at risk of kidney problems, such as those with high blood pressure or diabetes and those with a blood relative with chronic kidney disease. Chronic kidney disease may also be identified when it leads to one of its recognized complications, such as cardiovascular disease, anemia or pericarditis.[1] It is differentiated from acute kidney disease in that the reduction in kidney function must be present for over 3 months. Chronic kidney disease is identified by a blood test for creatinine. Higher levels of creatinine indicate a lower glomerular filtration rate and as a result a decreased capability of the kidneys...
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