title: In vivo elemental partition analysis using fast neutrons. A tool for testing the efficacy of new clinical interventions.
abstract: The nutritional status of patients can be evaluated by monitoring changes in body composition, including depletion of protein and muscle; distribution of adipose tissue; and changes in hydration status, and bone or cell mass. Fast neutron activation (for N and P) and neutron inelastic scattering (for C and O) are used to assess in vivo elements characteristic of specific body compartments. Nonbone phosphorus for muscle is measured by the 31P(n,alpha)28Al reaction, and nitrogen for protein via the (n,2n) fast neutron reaction. The carbon-to-oxygen (C/O) ratio is used to measure distribution of fat and lean tissue in the body and to monitor small changes in lean mass and its quality. In addition to evaluating the efficacy of new treatments, the method is used to study the mechanisms of depletion of lean tissue with aging.
authors.affiliation: USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts 02111, USA. kehayias@hnrc.tufts.edu
authors.forename: J J
authors.initials: JJ
authors.lastname: Kehayias
authors.forename: S
authors.initials: S
authors.lastname: Valtueña
authors.forename: A B
authors.initials: AB
authors.lastname: Waitekus
authors.forename: C A
authors.initials: CA
authors.lastname: Sheahan
authors.forename: M
authors.initials: M
authors.lastname: O'Neill
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D002118:Calcium / Q000032:analysis; D002244:Carbon / Q000032:analysis; D005214:Fast Neutrons; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009501:Neutron Activation Analysis / Q000295:instrumentation / Q000379:methods*; D009502:Neutrons; D009584:Nitrogen / Q000032:analysis; D009752:Nutritional Status; D010100:Oxygen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D012542:Scattering, Radiation
chemical_list: D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen; D010100:Oxygen; D002118:Calcium