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111.
The effect of dietary TAG structure and fatty acid acyl TAG position on palmitic and linoleic acid metabolism was investigated
in four middle-aged male subjects. The study design consisted of feeding diets containing 61 g/d of native lard (NL) or randomized
lard (RL) for 28 d. Subjects then received an oral dose of either 1,3-tetradeuteriopalmitoyl-2-dideuteriolinoleoyl-rac-glycerol or a mixture of 1,3-dideuteriolinoleoyl-2-tetradeuteriopalmitoyl-rac-glycerol and 1,3-hexadeuteriopalmitoyl-2-tetradeuteriolinoleoyl-rac-glycerol. Methyl esters of plasma lipids isolated from blood samples drawn over a 2-d period were analyzed by GC-MS. Results
showed that absorption of the 2H-fatty acids (2H-FA) was not influenced by TAG position. The 2H-FA at the 2-acyl TAG position were 85±4.6% retained after absorption. Substantial migration of 2H-16∶0 (31.2±8.6%) from the sn-2 TAG position to the sn-1,3 position and 2H-18∶2n−6 (52.8±6.4%) from the sn-1,3 position to the sn-2 position of chylomicron TAG occurred after initial absorption and indicates the presence of a previously unrecognized isomerization
mechanism. Incorporation and turnover of the 2H-FA in chylomicron TAG, plasma TAG, and plasma cholesterol esters were not influenced by TAG acyl position. Accretion of
2H-16∶0 from the sn-2 TAG position in 1-acylphosphatidylcholine was 1.7 times higher than 2H-16∶0 from the sn-1,3 TAG positions. Acyl TAG position did not influence 2H-18∶2n−6 incorporation in PC. The concentration of 2H-18∶2n−6-derived 2H-20∶4n−6 in plasma PC from subjects fed, the RL diet was 1.5 times higher than for subjects fed the NL diet, and this result
suggests that diets containing 16∶0 located at the sn-2 TAG position may inhibit 20∶4n−6 synthesis. The overall conclusion is that selective rearrangement of chylomicron TAG structures
diminishes but does not totally eliminate the metabolic and physiological effects of dietary TAG structure. 相似文献
112.
Robert E. Smith Charles S. Pinzino Cecil C. Chappelow Andrew J. Holder Elisabet L. Kostoryz Jill R. Guthrie Matthew Miller David M. Yourtee J. David Eick 《应用聚合物科学杂志》2004,92(1):62-71
The objective was to study the photocationic polymerization of an expanding monomer, 1,5,7,11‐tetraoxaspiro[5.5]undecane (TOSU), and an aromatic dioxirane, bisphenol A diglycidyl ether (BADGE). Both homopolymerizations and binary polymerizations were conducted. The homopolymer, poly(TOSU), was found to be a linear poly(carbonate), which was soluble in acetone. Poly(BADGE) products contained ether linkages in addition to primary and secondary alcohol functionalities. Binary polymerization products varied depending on the irradiation time and length of dark cure. 13C‐NMR analysis of binary polymerizate products revealed peaks not seen in homopolymer spectra consistent with the formation of copolymer linkages. Mass spectrometry data revealed peaks consistent with oligomers that contained both TOSU and BADGE mer units. The structures of key reaction products were proposed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 62–71, 2004 相似文献
113.
Weidong Li Fusheng Pan Yimeng Song Meidi Wang Hongjian Wang Shalik Walker Hong Wu Zhongyi Jiang 《中国化学工程学报》2017,25(11):1563-1580
Extraordinary mass transfer phenomenon is usually found when the small molecules pass through a confined structure, whose effective size is commensurate with the mean free path of the molecules. Small changes in the confined mass transfer structure (including size, morphology and properties) will lead to significant fluctuations of the mass transfer coefficient. The mass transfer of the penetrant molecules in the dense membranes for pervaporation, gas separation and so on, is located in the scope of confined mass transfer. Incorporating nanofillers into polymer matrix to construct mixed matrix membranes (MMMs) is an effective approach to tune the confined mass transfer structure and enhance the performance of the widely used polymeric membranes. This reviewfocuses on the construction andmanipulation of the confined structure in the polymeric membranes via incorporating one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) fillers.The comparison of the MMMs for pervaporation is summarized, and the research prospective of the MMMs is provided. 相似文献
114.
F. Wastin J. Rebizant J.P. Sanchez A. Blaise J. Goffart J.C. Spirlet C.T. Walker J. Fuger 《Journal of Alloys and Compounds》1994,210(1-2):83-89
Twelve new ternary intermetallic compounds of light actinide elements from Th to Pu, namely U4Tc7Si6, U4Tc7Ge6, Np4Ru7Ge6, U2Tc3Si5, Np2Re3Si5, Pu2Re3Si5, Th2Mo3Si4, U2Mo3Si4, U2Mo3Ge4, Np2Mo3Si4, Np2Mo3Ge4, and Pu2Mo3Si4, were obtained. The structures of these compounds are discussed as well as some preliminary physical property studies. Magnetic susceptibility measurements show that An2Mo3(Si or Ge)4 compounds are paramagnetic at all temperatures studied and that U4Tc7Si6 orders antiferromagnetically around 25 K. Mössbauer spectroscopy on Np4Ru7Ge6 does not show a magnetic splitting down to 4.2 K. 相似文献
115.
Hem Joshi Bryan R. Moser Shailesh N. Shah Anurag Mandalika Terry Walker 《European Journal of Lipid Science and Technology》2010,112(7):802-809
The low temperature operability and oxidative stability of cottonseed oil methyl esters (CSME) were improved with four anti‐gel additives as well as one antioxidant additive, gossypol. Low temperature operability and oxidative stability of CSME was determined by cloud point (CP), pour point (PP), cold filter plugging point (CFPP), and oxidative stability index (OSI). The most significant reductions in CP, PP, and CFPP in all cases were obtained with Technol®, with the average reduction in temperature found to be 3.9 °C. Gunk®, Heet®, and Howe's® were progressively less effective, as indicated by average reductions in temperature of 3.4, 3.0, and 2.8 °C, respectively. In all cases, the magnitude of CFPP reduction was greater than for PP and especially CP. Addition of gossypol, a polyphenolic aldehyde, resulted in linear improvement in OSI (R2 = 0.9804). The OSI of CSME increased from 5.0 to 8.3 h with gossypol at a concentration of 1000 ppm. 相似文献
116.
Ciara N. Murphy Susan P. Walker Teresa M. MacDonald Emerson Keenan Natalie J. Hannan Mary E. Wlodek Jenny Myers Jessica F. Briffa Tania Romano Alexandra Roddy Mitchell Carole-Anne Whigham Ping Cannon Tuong-Vi Nguyen Manju Kandel Natasha Pritchard Stephen Tong Tuuhevaha J. Kaituu-Lino 《International journal of molecular sciences》2021,22(14)
Biomarkers for placental dysfunction are currently lacking. We recently identified SPINT1 as a novel biomarker; SPINT2 is a functionally related placental protease inhibitor. This study aimed to characterise SPINT2 expression in placental insufficiency. Circulating SPINT2 was assessed in three prospective cohorts, collected at the following: (1) term delivery (n = 227), (2) 36 weeks (n = 364), and (3) 24–34 weeks’ (n = 294) gestation. SPINT2 was also measured in the plasma and placentas of women with established placental disease at preterm (<34 weeks) delivery. Using first-trimester human trophoblast stem cells, SPINT2 expression was assessed in hypoxia/normoxia (1% vs. 8% O2), and following inflammatory cytokine treatment (TNFα, IL-6). Placental SPINT2 mRNA was measured in a rat model of late-gestational foetal growth restriction. At 36 weeks, circulating SPINT2 was elevated in patients who later developed preeclampsia (p = 0.028; median = 2233 pg/mL vs. controls, median = 1644 pg/mL), or delivered a small-for-gestational-age infant (p = 0.002; median = 2109 pg/mL vs. controls, median = 1614 pg/mL). SPINT2 was elevated in the placentas of patients who required delivery for preterm preeclampsia (p = 0.025). Though inflammatory cytokines had no effect, hypoxia increased SPINT2 in cytotrophoblast stem cells, and its expression was elevated in the placental labyrinth of growth-restricted rats. These findings suggest elevated SPINT2 is associated with placental insufficiency. 相似文献
117.
Design and construction of expanded polystyrene embankments Practical design methods as used in the United Kingdom 总被引:2,自引:0,他引:2
D. J. Thompsett A. Walker R. J. Radley B. M. Grieveson 《Construction and Building Materials》1995,9(6):403-411
This paper covers the history of the use of expanded polystyrene (
) in light weight fill for road embankments. UK design requirements and physical properties of the
foam are covered together with two case studies. 相似文献
118.
119.
D. C. Weed T. W. Houston G. P. Jones A. L. Lakin C. C. Seow A. J. Rosas I. D. Morton D. Boskou I. D. Morton E. A. El Harith R. Walker J. W. T. Dickerson A. Wiseman F. Jay J. A. Gondal J. Woodward A. Wiseman H. Moaven Shahidi H. G. Muller J. R. Piggott R. Harper I. A. Adeyemi H. G. Muller M. J. Warwick B. J. F. Hudson G. G. Evans A. A. Nour J. E. McKay 《Journal of the science of food and agriculture》1975,26(4):533-548
120.
Fulgencio Saura‐Calixto Jara Pérez‐Jiménez Sonia Touriño José Serrano Elisabet Fuguet Josep Lluis Torres Isabel Goñi 《Molecular nutrition & food research》2010,54(7):939-946
Proanthocyanidins (PAs) or condensed tannins, a major group of dietary polyphenols, are oligomers and polymers of flavan‐3‐ol and flavan‐3, 4‐diols widely distributed in plant foods. Most literature data on PAs' metabolic fate deal with PAs that can be extracted from the food matrix by aqueous‐organic solvents ( extractable proanthocyanidins). However, there are no data on colonic fermentation of non‐extractable proanthocyanidins (NEPAs), which arrive almost intact to the colon, mostly associated to dietary fibre (DF). The aim of the present work was to examine colonic fermentation of NEPAs associated with DF, using a model of in vitro small intestine digestion and colonic fermentation. Two NEPA‐rich materials obtained from carob pod (Ceratonia siliqua L. proanthocyanidin) and red grapes (grape antioxidant dietary fibre) were used as test samples. The colonic fermentation of these two products released hydroxyphenylacetic acid, hydroxyphenylvaleric acid and two isomers of hydroxyphenylpropionic acid, detected by HPLC‐ESI‐MS/MS. Differences between the two products indicate that DF may enhance the yield of metabolites. In addition, the main NEPA metabolite in human plasma was 3,4‐dihydroxyphenyl acetic acid. The presence in human plasma of the same metabolites as were detected after in vitro colonic fermentation of NEPAs suggests that dietary NEPAs would undergo colonic fermentation releasing absorbable metabolites with potential healthy effects. 相似文献