87 research outputs found
Effect of Constitution on Mass of Individual Organs and Their Association with Metabolic Rate in HumansâA Detailed View on Allometric Scaling
Resting energy expenditure (REE)-power relationships result from multiple underlying factors including weight and height. In addition, detailed body composition, including fat free mass (FFM) and its components, skeletal muscle mass and internal organs with high metabolic rates (i.e. brain, heart, liver, kidneys), are major determinants of REE. Since the mass of individual organs scales to height as well as to weight (and, thus, to constitution), the variance in these associations may also add to the variance in REE. Here we address body composition (measured by magnetic resonance imaging) and REE (assessed by indirect calorimetry) in a group of 330 healthy volunteers differing with respect to age (17â78 years), sex (61% female) and BMI (15.9â47.8 kg/m2). Using three dimensional data interpolation we found that the inter-individual variance related to scaling of organ mass to height and weight and, thus, the constitution-related variances in either FFM (model 1) or kidneys, muscle, brain and liver (model 2) explained up to 43% of the inter-individual variance in REE. These data are the first evidence that constitution adds to the complexity of REE. Since organs scale differently as weight as well as height the âfitâ of organ masses within constitution should be considered as a further trait
Preliminary chemical analysis and biological testing of materials from the HRI catalytic two-stage liquefaction (CTSL) process. [Aliphatic hydrocarbons]
Coal-derived materials from experimental runs of Hydrocarbon Research Incorporated's (HRI) catalytic two-stage liquefaction (CTSL) process were chemically characterized and screened for microbial mutagenicity. This process differs from two-stage coal liquefaction processes in that catalyst is used in both stages. Samples from both the first and second stages were class-fractionated by alumina adsorption chromatography. The fractions were analyzed by capillary column gas chromatography; gas chromatography/mass spectrometry; direct probe, low voltage mass spectrometry; and proton nuclear magnetic resonance spectrometry. Mutagenicity assays were performed with the crude and class fractions in Salmonella typhimurium, TA98. Preliminary results of chemical analyses indicate that >80% CTSL materials from both process stages were aliphatic hydrocarbon and polynuclear aromatic hydrocarbon (PAH) compounds. Furthermore, the gross and specific chemical composition of process materials from the first stage were very similar to those of the second stage. In general, the unfractionated materials were only slightly active in the TA98 mutagenicity assay. Like other coal liquefaction materials investigated in this laboratory, the nitrogen-containing polycyclic aromatic compound (N-PAC) class fractions were responsible for the bulk of the mutagenic activity of the crudes. Finally, it was shown that this activity correlated with the presence of amino-PAH. 20 figures, 9 tables
Chemical analysis and mutational assay of distilled oils from the H-coal direct liquefaction process: a status report
Samples from the H-Coal process, a catalytic, single-stage, coal liquefaction technology, were chemically characterized and screened for microbial mutagenicity. For these investigations, a blend of light and heavy H-Coal process oils was fractionally distilled into 50/sup 0/F boiling point cuts. The chemical analyses and biological testing results presented in this status report deal primarily with the blended material and the distillate fractions boiling above 650/sup 0/F. Results from the microbial mutagenicity assays indicated that onset of biological activity in the crude materials occurred above 700/sup 0/F. Similar trends have been observed for Solvent Refined Coal (SRC) I, SRC II, Integrated Two-Stage Liquefaction (ITSL) and Exxon EDS process materials. After chemical class fractionation, the primary source of microbial mutagenicity of the crude boiling point cuts was the nitrogen-containing polycyclic aromatic compound (N-PAC) fractions. Amino polycyclic aromatic hydrocarbons (amino-PAH) were present at sufficient concentration levels in the N-PAC fractions to account for the observed mutagenic responses. In general, the chemical composition of the H-Coal materials studied was similar to that of other single-stage liquefaction materials. The degree of alkylation in these materials was determined to be greater than in the SRC and less than in the EDS process distillate cuts. 13 references, 8 figures, 11 tables
Chemical and toxicological characterization of organic constituents in fluidized-bed and pulverized coal combustion: a topical report
Coal combustion fly ash from both conventional pulverized coal combustion (PCC) and fluidized-bed combustion (FBC) have been characterized as to their organic constituents and microbial mutagenic activity. The PCC fly ash was collected from a commercial utility generating plant using a low sulfur coal. The FBC fly ash was from a bench-scale developmental unit at the Grand Forks Energy Technology Center. Bulk samples of each fly ash were extracted using benzene/methanol and further separated using high performance liquid chromatography (HPLC). Subfractions from the HPLC separation were analyzed by gas chromatography using both element-specific nitrogen-phosphorus detectors and flame ionization detectors. Microbial mutagenicity assay results indicated that the crude organic extracts were mutagenic, and that both the specific activity and the overall activity of the PCC material was greater than that of the FBC material. Comparison of results from assays using S. typhimurium, TA1538NR indicated that nitrated polycyclic aromatic compounds (PAC) were responsible for much of the mutagenic activity of the PCC material. Similar results were obtained for assays of the FBC organic extract with standard and nitroreductase-deficient strains of S. typhimurium, TA100 and TA1538. Mutagenically active HPLC fractions were analyzed using high resolution gas chromatography (HRGC) and GC mass spectrometry (GC/MS), as well as probe inlet low and high resolutions MS. The discovery and identification of nitrated, oxygenated PAC are important because the presence of both nitro and/or keto functionalities on certain PAC has been shown to confer or enhance mutagenic activity
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