Abstract:
:A relatively rapid procedure is described for the spectrophotometric determination of total tocopherol in red blood cells (RBC) based on a modification of the original Emmerie-Engel reaction. The critical feature in this method is the presence of a large amount of an added antioxidant, pyrogallol or ascorbic acid, during the saponification and extraction stages and the use of thin-layer chromatography for tocopherol purification. The total tocopherol levels of plasma and erythrocytes were determined for a number of human subjects, for patients with abetalipoproteinemia, and for rats. It was found that these levels had a wide range in normal human subjects but that the ratio of RBC to plasma tocopherol was relatively constant and equal to 0.18, uncorrected, and 0.21 when both RBC and plasma values were corrected to 100% recovery. The RBC-to-plasma ratio for rats was 0.39. The accuracy of this ratio determined by the spectrophotometric procedure was verified by measuring the distribution of [(14)C]tocopherol in RBC and plasma when radioactive vitamin E was introduced into the blood by both in vitro and in vivo techniques. The addition of radioactive tocopherol to RBC or plasma at the initial stage of the analysis permits an accurate determination of the total tocopherol in RBC or plasma by calculations based on the recovery of the added isotope. This procedure for erythrocyte tocopherol analysis is compared with a gas-liquid chromatographic method in current use.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Kayden HJ,Chow CK,Bjornson LKsubject
Has Abstractpub_date
1973-09-01 00:00:00pages
533-40issue
5eissn
0022-2275issn
1539-7262journal_volume
14pub_type
杂志文章abstract::Due to conflicting reports concerning the relationship between phospholipid transfer protein (PLTP) activity and mass in plasma, the protein concentration and activity of PLTP were assessed in fractions isolated by fast protein liquid chromatography from the plasma of healthy normolipidemic individuals. Using both pol...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2002-02-01 00:00:00
abstract::Imidazole catalyzed acylations of lysolipids by acyl-CoAs in water at room temperature and at a pH close to neutrality. In the presence of oleoyl-CoA and either lysophosphatidylcholine, 1-palmitoyl-sn-glycero-3-phosphocholine (LPC); lysophosphatidylglycerol, monoacyl-sn-glycero-3-phosphoglycerol; lysophosphatidyl acid...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.m200075-jlr200
更新日期:2002-07-01 00:00:00
abstract::Increased plasma concentrations of apolipoprotein A-IV (apoA-IV) in chronic renal disease suggest a metabolic role of the kidney for this antiatherogenic protein. Therefore, we investigated patients with various forms of proteinuria and found increased serum concentrations of apoA-IV in 124 nephrotic patients compared...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600178-JLR200
更新日期:2006-09-01 00:00:00
abstract::The composition of the emulsified oil and of the micellar phases obtained when a glyceride-fatty acid mixture is dispersed in bile salt solution has been defined. The micellar phase in equilibrium with the emulsified oil phase was obtained by filtration through Millipore filters. The behavior of different lipids in su...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1967-11-01 00:00:00
abstract::The proton NMR spectra of the N-methyl choline region of normal and lecithin:cholesterol acyltransferase (LCAT)-deficient lipoproteins and of egg yolk phosphatidylcholine-cholesterol 55:45 (mol %) vesicle mixtures have been examined in the presence and absence of manganous sulfate as a line-broadening reagent. Mangano...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract::Fatty liver is frequent in the apolipoprotein B (apoB)-defective genetic form of familial hypobetalipoproteinemia (FHBL), but interindividual variability in liver fat is large. To explain this, we assessed the roles of metabolic factors in 32 affected family members with apoB-defective FHBL and 33 related and unrelate...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300508-JLR200
更新日期:2004-05-01 00:00:00
abstract::A novel metabolite of d-delta-tocopherol was isolated from the urine of rats given d-3,4-[3H2]-delta-tocopherol intravenously. The metabolite was collected from the urine of rats given d-delta-tocopherol in the same manner as that of the labeled compound. It was found that the metabolites consisted of sulfate conjugat...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1984-01-01 00:00:00
abstract::Cigarette smokers have reduced levels of plasma high density lipoprotein (HDL) compared to nonsmokers and are at risk of premature cardiovascular disease. Previous work from this laboratory has shown that exposure of human plasma to gas-phase cigarette smoke (CS) inhibited the activity of lecithin:cholesterol acyltran...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1995-02-01 00:00:00
abstract::Each abdominal fat depot, such as mesenteric or epididymal, differently contributes to the development of insulin resistance. The aim of this study was to identify the genetic regions that contribute to fat accumulation in epididymal/mesenteric fat and to examine whether or not the genetic regions that affect glucose ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M009563
更新日期:2010-12-01 00:00:00
abstract::The extent to which lipid and apolipoprotein (apo) concentrations in tissue fluids are determined by those in plasma in normal humans is not known, as all studies to date have been performed on small numbers of subjects, often with dyslipidemia or lymphedema. Therefore, we quantified lipids, apolipoproteins, high dens...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2000-08-01 00:00:00
abstract::Purified liver plasma membranes were prepared from rats fed a high-fat, carbohydrate-free diet or a high-glucose, fat-free diet. Membranes from rats fed the high-fat diet bound significantly less 125I-labeled concanavalin A (Con A) than did those from rats fed the fat-free diets. The magnitude of the binding differenc...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1979-07-01 00:00:00
abstract::Autotaxin (ATX), which is highly expressed and secreted by adipocytes, functions as the key enzyme to generate lysophosphatidic acid (LPA) from lysophosphatidylcholine. Adipose tissue is the main source of circulating ATX that modulates plasma LPA levels. Upregulation of ATX expression in obese patients and mice is cl...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M075655
更新日期:2017-11-01 00:00:00
abstract::The Smith-Lemli-Opitz syndrome (SLOS) is a congenital birth defect syndrome caused by a deficiency of 3beta-hydroxysterol Delta(7)-reductase, the final enzyme in the cholesterol biosynthetic pathway. The patients have reduced plasma and tissue cholesterol concentrations with the accumulation of 7-dehydrocholesterol an...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::Ursodeoxycholic acid (UDCA, ursodiol) is used to prevent damage to the liver in patients with primary biliary cirrhosis. The drug also prevents the progression of colorectal cancer and the recurrence of high-grade colonic dysplasia. However, the molecular mechanism by which UDCA elicits its beneficial effects is not e...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M021733
更新日期:2012-04-01 00:00:00
abstract::In human serum, polymorphism of apoA-II predominantly in HDL3 could be demonstrated. HDL3-apoA-II was composed of four isoproteins, each with a molecular weight of 8600 (reduced form) and identical immunological properties. The isoproteins are designated apoA-II-1 (pI 5.16), apoA-II-2 (pI 4.89) corresponding to the al...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1983-08-01 00:00:00
abstract::We have studied the recognition and uptake of acid lipase by human fibroblasts in order to determine requirements for localization and function of the enzyme in lysosomes. Our approach was based on evidence that a number of acid hydrolases involved in mucopolysaccharide metabolism are secreted from cultured fibroblast...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1982-01-01 00:00:00
abstract::Lysophospholipid (LP) research has experienced a period of renaissance with the discovery of the lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P) receptors in the late 1990s. Vertebrate LP receptors regulate embryogenesis, vascular development, neurogenesis, uterine development, oocyte survival, immune ce...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R800047-JLR200
更新日期:2009-04-01 00:00:00
abstract::Gluco- and galactocerebrosides can be separated by thin-layer chromatography on Silica Gel G prepared with sodium borate solution instead of water. The most successful developing system was chloroform-methanol-water-15 M NH(4)OH 280:70:6:1. ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1966-05-01 00:00:00
abstract::This report describes the chemical synthesis of isoursocholic acid (3 beta, 7 beta, 12 alpha-trihydroxy-5 beta-cholanoic acid) from its corresponding 3 alpha-analog. The method consists of refluxing a mixture of ursocholic acid, triphenylphosphine, and diethyl azodicarboxylate in benzene solution with an acid such as ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1991-08-01 00:00:00
abstract::Ceramide-1-phosphate (C1P) is a novel bioactive sphingolipid formed by the phosphorylation of ceramide catalyzed by ceramide kinase (CERK). In this study, we evaluated the mechanism by which increased C1P during phagocytosis enhances phagocytosis and phagolysosome formation in COS-1 cells expressing hCERK. Stable tran...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M700442-JLR200
更新日期:2008-03-01 00:00:00
abstract::AY 9944 is a novel inhibitor of cholesterol biosynthesis which appears to act on the Delta 7-reductase enzyme, interfering with the conversion of 7-dehydrocholesterol to cholesterol. In all tissues studied, with the exception of the lens, there was a reduction in cholesterol and a marked accumulation of 7-dehydrochole...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1966-01-01 00:00:00
abstract::This work describes the molecular mechanisms of fatty acid and hormonal modulations of the retinoid X receptor alpha (RXRalpha) in rat liver cells. We examined the effects of different fatty acids (myristic, stearic, oleic, linolenic, and arachidonic acids, EPA, and the peroxisomal proliferator TTA) and several hormon...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-04-01 00:00:00
abstract::Percent cholesterol absorption was measured in 94 normal subjects aged 17- 80 years while consuming diets generally low in cholesterol (mean intake = 226 +/- 126 mg/day). A new dual stable isotope method was used where a cholesterol tracer containing 6 extra mass units was given intravenously and another tracer with 5...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-02-01 00:00:00
abstract::Significant amounts of ursodeoxycholic acid (UDCA) used for the treatment of patients with primary biliary cirrhosis (PBC) become epimerized at C-3 to isoUDCA. We investigated the metabolism of isoUDCA and a possible pharmacologic effect in five patients (51.4 +/- 5.8 years old; 3 females, 2 males) with PBC and persis...
journal_title:Journal of lipid research
pub_type: 临床试验,杂志文章
doi:
更新日期:2001-05-01 00:00:00
abstract::Hypertriglyceridemia results from accumulation of triglyceride (TG)-rich lipoproteins (TRLs) in the circulation and is associated with increased CVD risk. ApoC-III is an apolipoprotein on TRLs and a prominent negative regulator of TG catabolism. We recently established that in vivo apoC-III predominantly inhibits LDL ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M093740
更新日期:2019-08-01 00:00:00
abstract::In vitro studies show that docosahexaenoic acid (DHA) can be released from membrane phospholipid by Ca(2+)-independent phospholipase A(2) (iPLA(2)), Ca(2+)-independent plasmalogen PLA(2) or secretory PLA(2 (sPLA2)), but not by Ca(2+)-dependent cytosolic PLA(2) (cPLA2), which selectively releases arachidonic acid (AA)....
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M006262
更新日期:2010-08-01 00:00:00
abstract::Maintaining cellular lipid homeostasis is crucial to oxidative tissues, and it becomes compromised in obesity. Lipid droplets (LD) play a central role in lipid homeostasis by mediating fatty acid (FA) storage in the form of triglyceride, thereby lowering intracellular levels of lipids that mediate cellular lipotoxicit...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M017939
更新日期:2011-12-01 00:00:00
abstract::LY295427, (3 alpha,4 alpha,5 alpha)-4-(2-propenylcholestan-3-ol), acts through an unknown mechanism to derepress the transcription of the low density lipoprotein (LDL) receptor in the presence of 25-hydroxycholesterol (25-OH chol). Preincubation with LY295427 in Chinese hamster ovary (CHO) cells increased uptake of 25...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1996-12-01 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::Apolipoprotein C-II (apoC-II) plays a critical role in the metabolism of plasma lipoproteins as an activator for lipoprotein lipase. Human apoC-II consists of 79 amino acid residues (pro-apoC-II). A minor fraction is converted to a mature form by cleavage at the site QQDE releasing the 6 amino-terminal residues. We ha...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1991-11-01 00:00:00