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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1990-4-5
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pubmed:abstractText |
The mechanism by which parathyroid hormone-related protein (PTH-RP) stimulates bone resorption is not known. Like certain other resorbing agents it may act to release bone-resorbing cytokines from the osteoblast. To examine this hypothesis, we used serum-free conditioned media (CM) from SAOS II cells incubated with 10(-8) M h(1-74) PTH-RP for 48 h. Treated CM contained substantially more bone-resorbing activity (BRA) in the fetal-rat long-bone assay than CM from untreated cells (2.17 +/- 0.21 vs 1.38 +/- 0.16 fold stimulation over basal [f]; p less than 0.05]. After centrifugation and dialysis, 1 liter of treated CM contained a total BRA of 7102 ngeq b(1-34) PTH with a specific activity (SA) of 447 ngeq b(1-34) PTH/mg protein. Treated CM did not stimulate the ROS assay and the cytokines PGE2, TGF-alpha, EGF, GM-CSF and IL-1 were present in low concentrations. The BRA was heat sensitive. Ultrafiltration revealed that 97% of the BRA was in a 3-30 kD fraction. Further purification was achieved by sequential reverse phase HPLC and size exclusion-HPLC (SE-HPLC). A single fraction containing BRA from SE-HPLC was purified 277-fold to a SA of 123,810 ngeq b(1-34) PTH/mg protein and had an apparent MW of 9 kD. SDS-PAGE revealed 4 bands in this SE-HPLC fraction with 1 band at 9 kD unique to that fraction. PTH-RP may cause bone resorption in part by stimulating the release of a 9 kD protein from osteoblasts which is responsible for activating osteoclasts.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Biological Factors,
http://linkedlifedata.com/resource/pubmed/chemical/Culture Media,
http://linkedlifedata.com/resource/pubmed/chemical/Cytokines,
http://linkedlifedata.com/resource/pubmed/chemical/PTHLH protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/Parathyroid Hormone-Related Protein,
http://linkedlifedata.com/resource/pubmed/chemical/Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/bone resorption factor
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pubmed:status |
MEDLINE
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pubmed:month |
Mar
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pubmed:issn |
0013-7227
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
126
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1783-5
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:2307127-Biological Factors,
pubmed-meshheading:2307127-Cell Line,
pubmed-meshheading:2307127-Chromatography, High Pressure Liquid,
pubmed-meshheading:2307127-Culture Media,
pubmed-meshheading:2307127-Cytokines,
pubmed-meshheading:2307127-Electrophoresis, Polyacrylamide Gel,
pubmed-meshheading:2307127-Humans,
pubmed-meshheading:2307127-Molecular Weight,
pubmed-meshheading:2307127-Osteoblasts,
pubmed-meshheading:2307127-Parathyroid Hormone-Related Protein,
pubmed-meshheading:2307127-Proteins
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pubmed:year |
1990
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pubmed:articleTitle |
The parathyroid hormone-related protein stimulates human osteoblast-like cells to secrete a 9,000 dalton bone-resorbing protein.
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pubmed:affiliation |
Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06510.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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