http://www.sciencemadness.org/talk/files.php?pid=78294&aid=1880

A simplification of the protein assay method of Lowry et al. which is more generally applicable

The 11th edition of Harrison's Principles of Internal Medicine welcomes Anthony Fauci to its editorial staff, in addition to more than 85 new contributors. While the organization of the book is similar to previous editions, major emphasis has been placed on disorders that affect multiple organ systems. Important advances in genetics, immunology, and oncology are emphasized. Many chapters of the book have been rewritten and describe major advances in internal medicine. Subjects that received only a paragraph or two of attention in previous editions are now covered in entire chapters. Among the chapters that have been extensively revised are the chapters on infections in the compromised host, on skin rashes in infections, on many of the viral infections, including cytomegalovirus and Epstein-Barr virus, on sexually transmitted diseases, on diabetes mellitus, on disorders of bone and mineral metabolism, and on lymphadenopathy and splenomegaly. The major revisions in these chapters and many

Harrison's Principles of Internal Medicine

A modification of the Lowry procedure to simplify protein determination in membrane and lipoprotein samples

A method for the quantitative recovery of protein in dilute solution in the presence of detergents and lipids

A rapid, sensitive, and versatile assay for protein using Coomassie brilliant blue G250

http://www.jbc.org/content/264/3/1767.full.pdf

Secretion and degradation of lipoprotein lipase in cultured adipocytes. Binding of lipoprotein lipase to membrane heparan sulfate proteoglycans is necessary for degradation.

Background-Recent studies in mice have established that an endothelial cell protein, glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), is essential for the lipolytic processing of triglyceride-rich lipoproteins. Methods and Results-We report the discovery of a homozygous missense mutation in GPIHBP1 in a young boy with severe chylomicronemia. The mutation, p.C65Y, replaces a conserved cysteine in the GPIHBP1 lymphocyte antigen 6 domain with a tyrosine and is predicted to perturb protein structure by interfering with the formation of a disulfide bond. Studies with transfected Chinese hamster ovary cells showed that GPIHBP1-C65Y reaches the cell surface but has lost the ability to bind lipoprotein lipase (LPL). When the GPIHBP1-C65Y homozygote was given an intravenous bolus of heparin, only trace amounts of LPL entered the plasma. We also observed very low levels of LPL in the postheparin plasma of a subject with chylomicronemia who was homozygous for a different GPIHBP1 mutation (p.Q115P). When the GPIHBP1-Q115P homozygote was given a 6-hour infusion of heparin, a significant amount of LPL appeared in the plasma, resulting in a fall in the plasma triglyceride levels from 1780 to 120 mg/dL. Conclusions-We identified a novel GPIHBP1 missense mutation (p.C65Y) associated with defective LPL binding in a young boy with severe chylomicronemia. We also show that homozygosity for the C65Y or Q115P mutations is associated with low levels of LPL in the postheparin plasma, demonstrating that GPIHBP1 is important for plasma triglyceride metabolism in humans. ( Circ Cardiovasc Genet. 2010; 3: 169-178.)

Chylomicronemia with low postheparin lipoprotein lipase levels in the setting of GPIHBP1 defects.

SummaryIt has been demonstrated with the use of a functionally hepatectomized preparation and in the presence of a lipoprotein lipase inhibitor, Triton WR 1339, that, in the chicken, long chain fatty acids are absorbed in the form of triglycerides as the major component of a lipoprotein of density less than 1.006.

André Bensadoun

Papers

Secretion and degradation of lipoprotein lipase in cultured adipocytes. Binding of lipoprotein lipase to membrane heparan sulfate proteoglycans is necessary for degradation.

Chylomicronemia with low postheparin lipoprotein lipase levels in the setting of GPIHBP1 defects.

The form of absorption of lipids in the chicken, Gallus domesticus.

Hepatic lipase is abundant on both hepatocyte and endothelial cell surfaces in the liver.

Angiopoietin-like 4 promotes intracellular degradation of lipoprotein lipase in adipocytes.