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81.
D. Pimentel S. Cooperstein H. Randell D. Filiberto S. Sorrentino B. Kaye C. Nicklin J. Yagi J. Brian J. O’Hern A. Habas C. Weinstein 《Human ecology: an interdisciplinary journal》2007,35(6):653-668
The World Health Organization (WHO) and other organizations report that the prevalence of human diseases during the past decade
is rapidly increasing. Population growth and the pollution of water, air, and soil are contributing to the increasing number
of human diseases worldwide. Currently an estimated 40% of world deaths are due to environmental degradation. The ecology
of increasing diseases has complex factors of environmental degradation, population growth, and the current malnutrition of
about 3.7 billion people in the world. 相似文献
82.
Weinstein DS Liu W Ngu K Langevine C Combs DW Zhuang S Chen C Madsen CS Harper TW Robl JA 《Bioorganic & medicinal chemistry letters》2007,17(18):5115-5120
A series of 2,4,5-tri-substituted imidazoles has proven to be highly potent in inhibiting mammalian 15-lipoxygenase (15-LO) with excellent selectivity over human isozymes 5- and P-12-LO. Non-symmetrical sulfamides (e.g., 21a-n) were found to be suitable replacements for the earlier arylsulfonamide-containing members of this series (e.g., 2, 14a-p). Several members of these series also demonstrated potent inhibition of human 15-LO in a cell-based assay. 相似文献
83.
GPIHBP1: an endothelial cell molecule important for the lipolytic processing of chylomicrons 总被引:1,自引:0,他引:1
Young SG Davies BS Fong LG Gin P Weinstein MM Bensadoun A Beigneux AP 《Current opinion in lipidology》2007,18(4):389-396
PURPOSE OF REVIEW: To summarize recent data indicating that glycosylphosphatidylinositol-anchored high density lipoprotein-binding protein 1 (GPIHBP1) plays a key role in the lipolytic processing of chylomicrons. RECENT FINDINGS: Lipoprotein lipase hydrolyses triglycerides in chylomicrons at the luminal surface of the capillaries in heart, adipose tissue, and skeletal muscle. The endothelial cell molecule that facilitates the lipolytic processing of chylomicrons has never been clearly defined. Mice lacking GPIHBP1 manifest chylomicronemia, with plasma triglyceride levels as high as 5000 mg/dl. In wild-type mice, GPIHBP1 is expressed on the luminal surface of capillaries in heart, adipose tissue, and skeletal muscle. Cells transfected with GPIHBP1 bind both chylomicrons and lipoprotein lipase avidly. SUMMARY: The chylomicronemia in Gpihbp1-deficient mice, the fact that GPIHBP1 is located within the lumen of capillaries, and the fact that GPIHBP1 binds lipoprotein lipase and chylomicrons suggest that GPIHBP1 is a key platform for the lipolytic processing of triglyceride-rich lipoproteins. 相似文献
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Osteoclasts resorb the mineralized matrices formed by chondrocytes or osteoblasts. The cytokine receptor activator of nuclear factor-κB ligand (RANKL) is essential for osteoclast formation and thought to be supplied by osteoblasts or their precursors, thereby linking bone formation to resorption. However, RANKL is expressed by a variety of cell types, and it is unclear which of them are essential sources for osteoclast formation. Here we have used a mouse strain in which RANKL can be conditionally deleted and a series of Cre-deleter strains to demonstrate that hypertrophic chondrocytes and osteocytes, both of which are embedded in matrix, are essential sources of the RANKL that controls mineralized cartilage resorption and bone remodeling, respectively. Moreover, osteocyte RANKL is responsible for the bone loss associated with unloading. Contrary to the current paradigm, RANKL produced by osteoblasts or their progenitors does not contribute to adult bone remodeling. These results suggest that the rate-limiting step of matrix resorption is controlled by cells embedded within the matrix itself. 相似文献
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M Morotomi P LoGerfo I B Weinstein 《Biochemical and biophysical research communications》1991,181(3):1028-1034
In a previous paper we demonstrated that human fecal bacteria can convert phosphatidylcholine to diacylglycerol (DAG), an activator of protein kinase C. The present study demonstrates that several foods contain appreciable levels of DAG, especially certain vegetable oils. On the other hand, when rats were administered [14C]-labeled DAG by intragastric intubation less than 0.1% of the administered radioactivity was recovered as DAG in the feces. Thus only negligible amounts of dietary DAG actually reach the colon. When [14C]DAG was injected directly into ligated segments of rat colon we found appreciable uptake of the intact DAG by the mucosal cells. The major metabolite was arachidonic acid, suggesting that the DAG lipase pathway is more active than the DAG kinase pathway in these cells. Taken together, these results are consistent with our hypothesis that much of the DAG present in the colonic lumen is produced by the intestinal bacteria and that this DAG can actually enter the colonic mucosal cells, where it might influence their function. 相似文献
89.
Band 3 protein of the red cell membrane of the llama: crosslinking and cleavage of the cytoplasmic domain 总被引:1,自引:0,他引:1
Comparative studies were done on the cytoplasmic domain of the band 3 protein in the red cell membranes of the the human and the llama. Two approaches were used: crosslinking with o-phenanthroline/CuSO4, and cleavage with 2-nitro-5-thiocyanobenzoate. o-Phenanthroline/CuSO4 crosslinks the band 3 polypeptide chains in the human; in contrast band 3 in the llama is minimally crosslinked by this agent. 2-Nitro-5-thiocyanobenzoate cleaves band 3 in the human into a 23,000-dalton fragment; a similar fragment is not generated from the llama band 3. These studies show that the cysteine residue located 23,000 daltons from the N-terminus of band 3 in the human involved in these reactions is unavailable for crosslinking and cleavage in the llama. Species differences in the cytoplasmic domain of band 3 may contribute to the unusual resistance of llama red cells to osmotic, chemical and physically-induced deformation. 相似文献