Abstract:
:In promoting oxidation of 0.02 m potassium linoleate in a buffered (pH 7.0) aqueous dispersion at 37 degrees C, ascorbic acid at low concentrations (1.8 x 10(-6) and 1.8 x 10(-5) m) in combination with copper (1.3 x 10(-7) to 1.3 x 10(-3) m) had greater catalytic activity than the additive activity of the two catalysts individually. Possible explanations for the enhanced catalysis include reduction of copper by ascorbic acid to the cuprous form, increased concentration of semidehydroascorbic acid radical, and formation of a metal-ascorbic acid-oxygen complex. Some combinations of ascorbic acid (1.8 x 10(-4) and 1.8 x 10(-3) m) and copper (1.3 x 10(-6) and 1.3 x 10(-3) m) inhibited the formation of conjugated dienes but not the oxidation of ascorbic acid, and caused rapid loss of part of the conjugated dienes that were already present. It is suggested that free-radical inhibitors formed by the combination of catalysts inhibit initiation of lipid oxidation but not copper-catalyzed oxidation of ascorbic acid. Effects of the inhibitory combinations on changes in UV absorption by conjugated dienes, and absorbance in the TBA test, indicate the presence of at least two conjugated dienes that differ in stability.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Haase G,Dunkley WLsubject
Has Abstractpub_date
1969-09-01 00:00:00pages
568-76issue
5eissn
0022-2275issn
1539-7262journal_volume
10pub_type
杂志文章abstract::Although the synthesis pathways of intracellular triacylglycerol (TAG) species have been well elucidated, assessment of the contribution of an individual pathway to TAG pools in different mammalian organs, particularly under pathophysiological conditions, is difficult, although not impossible. Herein, we developed and...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M033837
更新日期:2013-04-01 00:00:00
abstract::Electrospray ionization mass spectrometry has previously been used to probe qualitative changes in the phospholipid cardiolipin (CL), but it has rarely been used in a quantitative manner. We assessed changes in the amount of individual molecular species of cardiac CL present in a model of congestive heart failure usin...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M500031-JLR200
更新日期:2005-06-01 00:00:00
abstract::We elucidated the mechanisms of action of two n-3 PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in Jurkat T-cells. Both DHA and EPA were principally incorporated into phospholipids in the following order: phosphatidylcholine < phosphatidylethanolamine < phosphatidylinositol/phosphatidylserine. Fur...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M400444-JLR200
更新日期:2005-04-01 00:00:00
abstract::Endothelial dysfunction is a key step in atherosclerosis development. Our recent studies suggested that oxLDL-induced increase in endothelial stiffness plays a major role in dyslipidemia-induced endothelial dysfunction. In this study, we identify oxysterols, as the major component of oxLDL, responsible for the increas...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M027102
更新日期:2012-07-01 00:00:00
abstract::Fatty acid translocase (FAT/CD36) is a membrane protein putatively involved in the transmembrane transport of long-chain fatty acids. We tested the hypothesis that expression of this protein in H9c2, a rat heart cell line normally not expressing FAT, would increase cellular palmitate uptake. We were able to stably tra...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-10-01 00:00:00
abstract::A variety of methods are currently used to analyze HL and LPL activities in mice. In search of a simple methodology, we analyzed mouse preheparin and postheparin plasma LPL and HL activities using specific polyclonal antibodies raised in rabbit against rat HL (anti-HL) and in goat against rat LPL (anti-LPL). As an alt...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D700021-JLR200
更新日期:2007-12-01 00:00:00
abstract::Mutational inactivation of NPC1 largely blocks the movement of LDL-derived cholesterol from the lysosome to the metabolically active, cytosolic pool of sterol that is the substrate for steroid hormone production. Such a block might, in theory, lead to deficiencies in circulating levels of testosterone, progesterone, a...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M500534-JLR200
更新日期:2006-05-01 00:00:00
abstract::ACAT catalyzes the formation of cholesteryl esters from cholesterol and long-chain fatty acids. There are two known genes encoding the two ACAT enzymes, ACAT1 and ACAT2 (also known as Soat1 and Soat2). In adult humans, ACAT1 is present in most tissues, whereas ACAT2 is localized to enterocytes and hepatocytes. In this...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M400450-JLR200
更新日期:2005-09-01 00:00:00
abstract::A woman with primary lipoprotein lipase (LPL) deficiency developed marked hypertriglyceridemia, pancreatitis, eruptive xanthomas, and unusual palmar xanthomas during pregnancy. Hypotheses to account for the palmar xanthomas were that oxidative modification of triglyceride (TG)-rich lipoproteins occurred due to increas...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1996-05-01 00:00:00
abstract::Oxylipins are potent lipid mediators involved in a variety of physiological processes. Their profiling has the potential to provide a wealth of information regarding human health and disease and is a promising technology for translation into clinical applications. However, results generated by independent groups are r...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.RA120000991
更新日期:2020-11-01 00:00:00
abstract::The effect of electron transport chain redox status on activity of the mitochondrial Ca(2+)-independent phospholipase A2 (iPLA2) has been examined. When oxidizing NAD-linked substrates, the enzyme is not active unless deenergization occurs. Uncoupler, rotenone, antimycin A, and cyanide are equally effective at upregul...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M043307
更新日期:2014-05-01 00:00:00
abstract::Niemann-Pick C1-like 1 (NPC1L1) is a recently identified protein that mediates intestinal cholesterol absorption and regulates biliary cholesterol excretion. The itineraries and kinetics of NPC1L1 trafficking remain uncertain. In this study, we have visualized movement of NPC1L1-enhanced green fluorescent protein (NPC...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800145-JLR200
更新日期:2008-09-01 00:00:00
abstract::The inbred C57L strain but not the AKR strain of mice carry Lith genes that determine cholesterol gallstone susceptibility. When C57L mice are fed a lithogenic diet containing 15% fat, 1% cholesterol, and 0.5% cholic acid, gallbladder bile displays rapid cholesterol supersaturation, mucin gel accumulation, increases i...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract::The potential role of the very low density lipoprotein (VLDL) receptor in mediating VLDL-induced plasminogen activator inhibitor-1 (PAI-1) expression was studied in vitro. Cultured endothelial cells incubated with VLDL showed an increased secretion of PAI-1. This response to VLDL could be completely prevented by the r...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-05-01 00:00:00
abstract::apoE is a multi-functional protein expressed in several cell types and in several organs. It is highly expressed in adipose tissue, where it is important for modulating adipocyte lipid flux and gene expression in isolated adipocytes. In order to investigate a potential systemic role for apoE that is produced in adipos...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M050567
更新日期:2015-02-01 00:00:00
abstract::The origin of the cholesterol needed by the cornea for growth and cell turnover was addressed by comparing absolute rates of sterol synthesis with rates of sterol accumulation during early development of the rabbit. Linearity of incorporation of 3H2O and [14C]mevalonate into digitonin-precipitable sterols with time of...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1989-07-01 00:00:00
abstract::Epoxyeicosatrienoic acids were isolated and purified from female rabbit kidneys. They were identified as a group, prior to resolution, by packed column gas-liquid chromatography-mass spectroscopic techniques as their methyl esters as well as their trimethylsilyl bromohydrin methyl esters. Initial capillary gas-liquid ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1987-07-01 00:00:00
abstract::This review presents an overview of mammalian phospholipid synthesis and the cellular locations of the biochemical activities that produce membrane lipid molecular species. The generalized endoplasmic reticulum compartment is a central site for membrane lipid biogenesis, and examples of the emerging relationships betw...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R800049-JLR200
更新日期:2009-04-01 00:00:00
abstract::Adipocyte triglyceride storage provides a reservoir of energy that allows the organism to survive times of nutrient scarcity, but excessive adiposity has emerged as a health problem in many areas of the world. Monoacylglycerol acyltransferase (MGAT) acylates monoacylglycerol to produce diacylglycerol; the penultimate ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M084947
更新日期:2018-09-01 00:00:00
abstract::The surface area, A, of contracting fatty acid monolayers was measured as a function of time, t, at constant surface pressure. In the initial temporal phase, ln A was linear with radical t. In a subsequent steady-state phase, ln A was linear with t. The initial desorption coefficient for sodium palmitate, K(i), and th...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1973-01-01 00:00:00
abstract::A qualitative iodometric test for lipoxygenase activity is described. The sensitive method is useful for rapidly screening large numbers of samples, as from a chromatography column or after enzyme inactivation treatment in food processing. ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1972-03-01 00:00:00
abstract::HDL-like particles in human cerebrospinal fluid (CSF) promote the efflux of cholesterol from astrocytes toward the neurons that rely on this supply for their functions. We evaluated whether cell cholesterol efflux capacity of CSF (CSF-CEC) is impaired in Alzheimer's disease (AD) by analyzing AD (n = 37) patients, non-...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.P091033
更新日期:2019-08-01 00:00:00
abstract::Experimental approaches involving the perfusion of tissues and organs offer the advantage of improved physiological relevance over the use of isolated tissues or cells while at the same time being much more controlled and tissue-specific than studies in vivo. Nevertheless, there have been few metabolic studies perform...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D500016-JLR200
更新日期:2005-08-01 00:00:00
abstract::Spectrophotometric techniques for determining the activities of lipases, lysophospholipases, and phospholipases are reviewed. These methods involve the use of thioester substrate analogs as well as omega-nitrophenyl derivatives of the corresponding lipids. The most promising results are obtained with the thioester sub...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:
更新日期:1984-12-15 00:00:00
abstract::Rat lymph chylomicrons were treated with rat heparin-releasable hepatic lipase (HL) or with bovine milk lipoprotein lipase (LPL). The ability of the resulting particles to be taken up by the liver in vivo was assessed following their infusion into the portal vein of partially hepatectomized animals. The following obse...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1988-08-01 00:00:00
abstract::The demand to study the cellular localization of specific lipids has led to recent advances in lipid probes and microscopy. Alkyne lipids bear a small, noninterfering tag and can be detected upon click reaction with an azide-coupled reporter. Fluorescent alkyne lipid imaging crucially depends on appropriate azide repo...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D070565
更新日期:2016-10-01 00:00:00
abstract::Two new 6-hydroxylated bile acids, 3 beta, 6 alpha, 12 alpha- and 3 beta, 6 beta, 12 alpha-trihydroxy-5 beta-cholanoic acids, were synthesized from deoxycholic acid. In addition, their C-3 epimers, 3 alpha, 6 alpha, 12 alpha- and 3 alpha, 6 beta, 12 alpha-trihydroxy acids, were prepared by a new route. The principal r...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1991-04-01 00:00:00
abstract::Circulating triacylglycerol (TG) arises mainly from dietary fat. However, little is known about the entry of dietary fat into the major TG pool, very low-density lipoprotein (VLDL) TG. We used a novel method to study the specific incorporation of dietary fatty acids into postprandial VLDL TG in humans. Eight healthy v...
journal_title:Journal of lipid research
pub_type: 临床试验,杂志文章
doi:10.1194/jlr.M300167-JLR200
更新日期:2003-11-01 00:00:00
abstract::The isolated perfused mouse liver was utilized to evaluate the relative contribution of various molecules believed to participate in the removal of chylomicron remnants by the liver. Sixty percent of asialofetuin was removed from the perfusate per pass; bovine serum albumin was not removed. Normal mouse livers removed...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract::At 123 K, crystals of cholesteryl cis-9-hexadecenoate (cholesteryl palmitoleate, C45H74O2) are monoclinic, space group P2(1) with cell dimensions a = 12.917(7), b = 8.910(5), c = 34.04(1) A, beta = 94.95(7) degrees [lambda(CuK alpha) = 1.5424 A] having two independent molecules (A and B) per unit cell. The crystal str...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1984-08-01 00:00:00