bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blood polyunsaturated fatty acids in patients with peroxisomal disorders. A multicenter study
Authors: Martinez Manuela , Mougan Isabel , Roig Manuel , Ballabriga Angel 
Published: November 2006

AbstractThe purpose of the study was to compare the polyunsaturated fatty acid (PUFA) status in patients with X‐linked adrenoleukodystrophy or adrenomyeloneuropathy (X‐ALD/AMN) with that in disorders of peroxisome biogenesis (PB). Total fatty acids and plasmalogens were quantified in plasma and red cells from 28 patients with X‐ALD/AMN, 26 patients with generalized peroxisomal disorders, and 37 controls. Total fatty acid methyl esters and plasmalogen dimethyl acetals were obtained by direct transmethylation and separated by capillary column gas chromatography. The results confirm previous findings in that docosahexaenoic acid (DHA, 22∶6n−3) was greatly decreased in both plasma and erythrocytes from patients with PB disorders. When nutritional conditions were adequate, patients with X‐ALD/AMN had normal levels of DHA. A highly significant positive correlation was found between the levels of DHA and those of plasmalogens in peroxisomal patients. As in other tissues, the parent n−6 fatty acid, linoleic acid (LA, 18∶2n−6) was significantly increased in red cells from PB patients, whereas arachidonic acid (20∶4n−6) was virtually within normal limits. In clear contrast to red cells and other tissues, arachidonate was significantly lower in plasma from PB patients. The decrease in plasma arachidonate and the high tissue levels of LA suggest a defect of Δ6 desaturase and/or Δ5 desaturase in PB patients. The n−6 fatty acids were normal in X‐ALD/AMN patients. The present data show that X‐ALD/AMN patients do not have the profound PUFA alterations that PB patients have, at least in blood.
Sponge fatty acids. 3. Occurrence of series of n−7 monoenoic andiso‐5,9 dienoic long‐chain fatty acids in the phospholipids of the marine spongeCinachyrella aff.schulzei keller
Authors: Barnathan Gilles , Doumenq Pierre , Njinkoué Jean‐Michel , Mirallès Joseph , Debitus Cécile , Lévi Claude , Komprobst Jean‐Michel 
Published: November 2006

AbstractThe fatty acid composition of phospholipids from the New Caledonian spongeCinachyrella aff.schulzei Keller was studied. More than 60 fatty acids were identified as methyl esters andN‐acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. Two isoprenoid fatty acids also were shown to be present, namely 4,8,12‐trimethyltridecanoic and 5,9,13‐trimethyltetradecanoic acids. The unusual 6‐tetradecenoic, 6‐pentadecenoic, 12‐nonadecenoic and 26‐methylheptacosanoic (iso‐28∶0) acids were found for the first time in sponge phospholipids. A series of six n−7 monoenoic long‐chain fatty acids (C23 to C28) were identified, including the rare 16‐tricosenoic, 18‐pentacosenoic and 21‐octacosenoic acids. Fifteen fatty acids possessing the typical 5,9 dienoic moiety accounted for 30% of the total fatty acid mixture. Two new fatty acids were identified, namely 5(Z)‐octacosenoic and 27‐methyl‐5(Z),9(Z)‐octacosadienoic (iso‐5,9‐29∶2). Based on gas chromatography/Fourier transform infrared experiments, the double bonds were assigned the (Z) configuration.
A simple and precise method for the routine determination of platelet‐activating factor in blood and urine
Authors: Demopoulos Constantinos A. , Andrikopoulos Nikolaos K. , Antonopoulou Smaragdi 
Published: November 2006

AbstractA simple and precise method is described for the measurement of platelet‐activating factor (PAF) in blood and urine. The method involves the isolation of PAF from blood samples by two successive steps. In the first step, blood proteins are precipitated with ethanol and the “free” PAF, i.e. the PAF which is extractable with ethanol, is recovered. In the second step, “bound” PAF, i.e., PAF not extractable with ethanol, is extracted from the protein precipitate with chloroform/methanol/water. The extraction of PAF from urine samples requires only the ethanol extraction step. “Free” and “bound” PAF are then each fractionated by silicic acid column chromatography, and the methanol/water eluent containing PAF is then further fractionated by high‐performance liquid chromatography using an isocratic solvent system of acetonitrile/methanol/water. PAF is then quantitated by measuring its ability to induce platelet aggregation in an aggregometer. Application of the method to blood and urine samples from twenty‐three healthy volunteers revealed PAF levels in blood of 140–480 pg/mL (630–254.4 pg “free” PAF/mL and 64–225.6 pg “bound” PAF/mL), and of 1.2–4.0 pg PAF/mL in urine. The method overcomes various technical problems and was shown to be very precise. It should prove useful for monitoring PAF levels in various disease conditions.
Lipid composition of platelets from patients with atherosclerosis: Effect of purified eicosapentaenoic acid ethyl ester administration
Authors: Kamido Hiroshi , Matsuzawa Yuji , Tarui Seiichiro 
Published: November 2006

AbstractAlthough eicosapentaenoic acid (EPA) has been shown to have beneficial effects in the prevention of atherosclerosis, the mechanism by which these effects occur is not entirely clear. We investigated the lipid composition of platelets in paired subjects with and without atherosclerotic disease, either hypercholesterolemic (low density lipoprotein [LDL] cholesterol [Chol]≥170 mg/dl) or normocholesterolemic (LDL‐Chol<170 mg/dl). Platelets from patients with atherosclerotic disease had a lower phosphatidylcholine (PC)/Chol ratio, when compared with those from patients without atherosclerotic disease, irrespective of LDL‐Chol levels. Eleven patients with atherosclerotic disease were treated with purified. EPA ethyl ester (1.8 g/day), and changes in lipid composition of platelets were investigated. Plasma levels of total Chol and LDL‐Chol decreased significantly after EPA administration. The phospholipid (PL)/Chol ratio and the PC/Chol ratio in platelets from patients with atherosclerotic disease increased significantly after 4–10 wk EPA treatment. The EPA content in platelets increased, while the arachidonic acid (AA) content decreased. EPA‐induced changes in the PL/Chol and the PC/Chol ratios of platelets, as well as fatty acyl chain shifts, may be related to the beneficial effects in preventing atherosclerosis, possibly by increase in the membrane fluidity.
Induction of long‐lasting hypercholesterolemia in the rat fed a cystine‐enriched diet
Authors: Sérougne C. , Mathé D. , Lutton C. 
Published: November 2006

AbstractThe influence of dietary excess (5%) of L‐cystine on rat plasma lipoproteins was examined. After only one week of cystine feeding, an increase in the plasma cholesterol level and a decrease in triglyceride levels were observed. The increase in cholesterol level became greater when the duration of cystine‐enriched diet increased until eight weeks (+131% after eight weeks), but no further increase occurred between 8 and 20 weeks. This change was essentially due to the progressive increase in cholesterol levels in high density lipoproteins (HDL) and in lipoproteins isolated between 1.040 and 1.063 g/ml, i.e., certain low density lipoproteins (HDL2), and containing mainly apoE‐rich lipoproteins (HDL1). The decrease in plasma triglycerides resulted from that of chylomicrons and very low density lipoproteins (VLDL). The effects observed after four or eight weeks of cystine feeding were maintained for eight weeks after replacing the cystine diet by the standard diet. Ingestion of the standard diet containing either cholestyramine (2%) or probucol (0.25%) following eight weeks of cystine feeding significantly decreased plasma cholesterol levels. It is concluded that cystine‐fed rats are a useful tool of investigation for understanding mechanisms leading to increased plasma cholesterol level and for hypocholesterolemic drug trials.
Arachidonic acid uptake by phospholipids and triacylglycerols of rat brain subcellular membranes
Authors: Lin Teng‐Nan , MacQuarrie Ronald , Sun Grace Y. 
Published: November 2006

AbstractIn the presence of ATP, MgCl2 and CoASH, different subcellular membrane fractions isolated from rat cerebral cortex exhibited characteristic profiles for the incorporation of [1‐14C]arachidonic acid into phospholipids and triacylglycerols. In general, uptake of label by phosphatidylcholines was higher in the synaptic membranes, and that by phosphatidylinositols was higher in the microsomes and somal plasma membranes. A substantial amount of the labeled arachidonate was also incorporated into triacylglycerols, especially in the somal plasma membranes and microsomes. Enzymes mediating the transfer of arachidonic acid to phospholipids were unstable with respect to sample storage and exposure to elevated temperatures. In contrast, the acyltransferase for triacylglycerols was more stable to these factors. Washing the membranes with bovine serum albumin resulted in an enhancement of the incorporation of label into phosphatidylinositols without affecting that of phosphatidylcholines, but the incorporation into triacylglycerols was inhibited. Treatment of synaptosomes and plasma membranes with saponin resulted in an enhancement in the labeling of phospholipids, but the labeling of triacylglycerols was inhibited. Thus, although labeled arachidonic acid was incorporated into phospholipids and triacylglycerols in brain subcellular membranes, these two types of acyltransferases exhibited different properties and responded differently to membrane perturbing agents.
Eicosanoid synthesis in 7,12‐dimethylbenz(a)anthracene‐induced mammary carcinomas in Sprague‐Dawley rats fed primrose oil, menhaden oil or corn oil diet
Authors: Abou‐El‐Ela Soad H. , Prasse Keith W. , Carroll Richard , Wade Adelbert E. , Dharwadkar Suniti , Bunce Opal R. 
Published: November 2006

AbstractThe comparative effects of high‐fat diets (20%, w/w) on eicosanoid synthesis during mammary tumor promotion in 7,12‐dimethylbenz(a)anthracene (DMBA)‐induced rats were studied using diets containing 20% primrose oil (PO), 20% menhaden oil (MO) or 20% corn oil (CO). Sprague‐Dawley rats fed the PO or MO diet had 21% or 24% fewer adenocarcinomas, respectively, than rats fed the CO diet. Histologically (i.e., mitotic figures, inflammatory cell infiltration and necrosis), the CO‐fed rats exhibited the highest frequency of changes within tumors. Plasma fatty acid composition was significantly altered by diet, reflecting the composition of the oils which were being fed. Only the plasma of PO‐fed rats contained detectable levels of gamma‐linolenic acid (GLA). Arachidonic acid (AA) levels were significantly higher (p<0.05) in PO‐fed than in CO‐ or MO‐fed rats. MO‐fed rats had significantly higher levels of plasma palmitic acid, while palmitoleic, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were detected only in MO‐fed rats. As expected, linoleic acid (LA) and AA levels were lower (p<0.05) in the MO‐fed rats than in PO‐ or CO‐fed groups. The plasma of the CO‐fed rats contained significantly higher levels of oleic acid. Eicosanoid synthesis in mammary carcinomas of rats fed the 20%‐fat diets was 2–10 times higher than in mammary fat pads of control rats. The synthesis of PGE1 and LTB4 was significantly (p<0.05) higher in PO‐fed rats than in CO‐fed or MO‐fed rats, although PGE values were significantly (p<0.05) higher in CO‐fed rats than in Mo or PO groups. The synthesis of eicosanoids in both mammary fat pads and mammary carcinomas of MO‐fed rats was lower (p<0.05) than in tissues of rats fed either CO or PO diets due to less AA precursor being fed and/or to competition between n−6 and n−3 fatty acids for cyclooxygenase and lipoxygenase. The ratios of monoenoic to dienoic eicosanoids in both mammary fat pads and mammary carcinomas were higher in the PO group than in the MO or CO groups. These results suggest that inclusion of GLA (PO feeding) or EPA and DHA (MO feeding) in the diet may decrease malignancy by altering eicosanoid profiles.
Esterifications of 1‐ andrac‐2‐octanols with selected acids and acid derivatives using lipases
Authors: Sonnet Philip E. , Moore Gordon G. 
Published: November 2006

AbstractSeveral aliphatic acids and their ethyl, isopropenyl and 2,2,2‐trichloroethyl esters were allowed to react with 1‐ and 2‐octanols catalyzed by commercial lipase preparations of porcine pancreas and the fungiCandida rugosa, Aspergillus niger andMucor miehei.Comparisons of reactivity of the acids and esters were made in common organic solvents using the primary alcohol. Reactions of octanoic acid and its esters with 2‐octanol in hexane allowed an evaluation of stereoselectivity of the lipases with different substrates that carried the same (octanoyl) residue. A partial resolution ofrac‐2‐hexadecanol withA. niger lipase is described, and the utility of lipase selectivities (stereo, positional, fatty acid and ester) is discussed with reference to the data presented.
Interaction of rabbit lipoproteins and red blood cells with liposomes of egg yolk phospholipids
Authors: Mendez Armando J. , He Jin Lin , Huang Hui Sheng , Wen Shu Rong , Hsia S. L. 
Published: November 2006

AbstractAfter intravenous injection of liposomes prepared from egg yolk phospholipids into rabbits, the phospholipids were readily assimilated by the lipoproteins, and there were increases in the circulating levels of cholesterol and phospholipids. The increases in cholesterol level were mainly due to increases of free cholesterol. Gradient ultracentrifugation showed that the lipoproteins decreased in density, and gel filtration chromatography showed that they increased in particle size. Upon electrophoresis, they exhibited slower mobility. Liposomes recovered from rabbits 3 hr after the injection contained free cholesterol, apolipoproteins A‐I, E and traces of C. The apolipoprotein may target the liposomes for uptake by hepatocytes. Incubation of the liposomes with rabbit red blood cell membranes in vitro caused a decrease in cholesterol content of the membranes. However, the cholesterol/phosphate ratio in red blood cells isolated from the rabbits after the injection of liposomes did not change significantly, suggesting rapid replenishment of red blood cell cholesterol in vivo, possibly by equilibration with lipoprotein cholesterol or tissue cholesterol. These results suggest that the injection of phospholipid liposomes may have an antiatherogenic effect by the removal of tissue cholesterol and enhancing hepatic disposal of cholesterol through the reverse cholesterol transport mechanism.
Docosahexaenoic acid and other dietary polyunsaturated fatty acids suppress leukotriene synthesis by mouse peritoneal macrophages
Authors: Lokesh Belur R. , Black J. Mark , German J. Bruce , Kinsella John E. 
Published: November 2006

AbstractThe efficacy of individual ω‐t‐3 polyunsaturated fatty acids (PUFA) in altering eicosanoid synthesis in peritoneal macrophages was studied by feeding mice for 10 days a diet containing 2 wt% fat, which included 0.5 wt% ethyl esters of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) or linolenic acid (LNA). Upon stimulation with calcium ionophore A23187, macrophages from these animals produced significantly lower amounts of leukotriene C4, leukotriene B4 and 12‐hydroxyeicosatetraenoic acid, prostaglandin E2 and 6‐keto prostaglandin F1α compared with those obtained from animals on the diets containing olive oil or safflower oil. The decrease in leukotriene synthesis was similar in the animals fed DHA, EPA or LNA diets. This depression of eicosanoids by DHA and EPA was associated with decreased levels of arachidonic acid (AA); however, LA that altered eicosanoids did not have the same effect on AA levels.
Serum fatty acid proportions are altered during the year following acute Epstein‐Barr virus infection
Authors: Williams Lowell L. , Doody Dennis M. , Horrocks Lloyd A. 
Published: November 2006

AbstractBecause abnormal serum fatty acid (FA) proportions had been found at three months after infectious mononucleosis (IM) in a pilot study, serum total FA profiles of 20 normal college students were measured at monthly intervals for one year following an acute Epstein‐Barr virus (EBV) infection. Below normal proportions of arachidonic acid and a reversal of the usual serum ratio of linoleic and oleic acids were maximal during the third month after acute IM. These FA abnormalities coincided with the symptom of increased physical malaise, despite apparent clinical recovery, common after IM. Persistence of low linoleic acid content beyond six months postinfection occurred in all seven students who showed continued clinical symptoms. Estimation of FA enzyme activities over the post‐IM year suggested that FA elongation function was normal, but that FA desaturation enzyme activities were lower than normal, particularly early after EBV infection. An inability of the host to normalize the serum total linoleic/oleic acid ratio may parallel a delayed recovery from EBV infection and may offer insight into its pathogenesis.
Thiophosphoester analogs of phosphatidic acids: Spectrophotometric substrates for phosphomonoesterases
Authors: Nyquist David A. 
Published: November 2006

AbstractThiophosphoester analogs of dioctanoyl and didecanoyl phosphatidic acids were synthesized for use as substrates in spectrophotometric assays. These substrates are easily dispersable in aqueous media and release thiodiacylglycerols after phosphomonoesterase catalyzed hydrolysis. The free sulfhydryl of these thiodiacylglycerols reacts with the colorimetric reagent 5,5′‐dithiobis(2‐nitrobenzoic acid) (DTNB), allowing the reaction to be followed. These analogs were shown to be good substrates for calf intestine alkaline phosphatase (highest activity at alkaline pH) and phosphomonoesterases of partially purified beef brain cytosol (highest activity at physiologic pH). Cationic amphiphilic drugs inhibit the actions of alkaline phosphatase on the dioctanoyl analog, but did not inhibit enzymatic hydrolysis ofp‐nitrophenyl phosphate. In contrast, the beef brain cytosolic fractionp‐nitrophenyl phosphate hydrolysis was mildly inhibited, and the phosphatidic acid analog hydrolysis was increased slightly. Tetramisole inhibited all enzyme activities withp‐nitrophenyl phosphate, but was inhibitory only to the alkaline‐phosphatase activity with the phosphatidic acid analog.
Increased amounts of cholesterol precursors in lipoproteins after ileal exclusion
Authors: Koivisto Pekka V. I. , Miettinen Tatu A. 
Published: November 2006

AbstractSerum cholesterol precursor sterols reflect the activity of cholesterol synthesis. In this study, squalene, methyl sterol and lathosterol contents were studied in very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL) of heterozygous familial hypercholesterolemia patients without and with ileal bypass. The contents of lathosterol and all methyl sterols (lanosterol, Δ8,24‐dimethylsterol, Δ8‐dimetylsterol, Δ8‐methostenol and methostenol), but not of squalene were increased in all lipoproteins by ileal bypass. The increase in the free methyl sterols was more marked than that in the esterified ones. The percentage esterification of the methyl sterols was highest in HDL and lowest in VLDL. Lipoprotein methyl sterol contents were positively correlated with each other and with cholesterol synthesis. The methyl sterols were slightly concentrated in LDL, and squalene strongly concentrated in VLDL. It is concluded that long‐term stimulation of cholesterol synthesis increases the methyl sterols in all lipoproteins.
Incorporation of oleic acid and eicosapentaenoic acid into glycerolipids of cultured normal human fibroblasts
Authors: Miller Michael , Motevalli Mahnaz , Westphal David , Kwiterovich Peter O. 
Published: November 2006

AbstractConfluent skin fibroblasts from normal humans were incubated in serum free medium with up to 100 nmole/mL eicosapentaenoic acid (EPA; bound to albumin in a 4.6∶1 ratio) and compared with cells incubated with oleic acid (OA) at similar concentrations. The rate of [14C]OA incorporation into triacylglycerol (TG) (nmol/mg/h) was approximately 5‐fold greater than that of [14C]EPA. The mass of TG formed after incubation of fibroblasts with EPA was also significantly lower than that formed with OA (43.2 ±9.3vs. 59.5±6.6 μg/mg cell protein, respectively,P=0.006). The addition of excess, unlabeled EPA reduced the rate of incorporation of [14C]OA into TG whereas unlabeled OA stimulated incorporation of [14C]EPA into TG. When the cells were preincubated with human serum basic proteins (BP I, II and III), the mass of TG formed (compared to baseline) was significantly higher with the basic proteins whether OA or EPA was studied. Only BP I significantly stimulated the mass of cell phospholipids, an effect that occurred with either OA or EPA in the medium. The results suggest that in cultured normal human fibroblasts, OA is a better substrate for TG synthesis than EPA and that this effect may be accentuated by the presence of the basis proteins.
1‐O‐alk‐1′‐enyl‐2‐acyl‐glycerophosphoethanolamine content and molecular species composition in fish brain
Authors: Bell M. V. , Dick J. R. 
Published: November 2006

AbstractEthanolamine glycerophospholipids from the brains of both trout and cod comprised 36–38% of 1‐O‐alk‐1′‐enyl‐2‐acyl‐glycerophosphoethanolamine (GPE) determined using two methods. In 1‐O‐alk‐1′‐enyl‐2‐acyl‐GPE from trout brain, the main molecular species were 18∶1a/18∶1, 18∶0a/18∶1 and 16∶0a/18∶1, which totalled 63.3%, while polyunsaturated fatty acid (PUFA) containing species totalled only 18.2%. 1‐O‐Alk‐1′‐enyl‐2‐acyl‐GPE from cod brain was much more unsaturated with PUFA containing species totalling 52.6%, of which 18∶0a/20∶5n−3, 18∶1a/20∶5n−3 and 18∶1a/22∶6n−3 were predominant. In cod 18∶1a/18∶1, 18∶0a/18∶1 and 16∶0a/18∶1 were the only other species present at over 5% each, totalling 31.8%. In both cod and trout, small amounts of species containing 22∶4n−6 were found. The results of this and earlier studies indicate that there is considerable specificity of composition at the level of molecular species between different lipid classes and subclasses.
Phospholipids inDrosophila heads: Effects of visual mutants and phototransduction manipulations
Authors: Stark William S. , Lin Teng‐Nan , Brackhahn David , Christianson J. Scott , Sun Grace Y. 
Published: November 2006

AbstractA procedure was developed to label phospholipids inDrosophila heads by feeding radioactive phosphate (32Pi). High‐performance thin‐layer chromatography showed label incorporation into various phospholipids. After 24 h of feeding, major phospholipids labeled were phosphatidylethanolamine (PE), 47%; phosphatidylcholine (PC), 24%; and phosphatidylinositol (PI), 12%.Drosophila heads have virtually no sphingomyelin as compared with mammalian tissues. Notable label was in ethanolamine plasmalogen, lysophosphatidylethanolamine, lysophosphatidylcholine and lysophosphatidylinositol. Less than 1% of the total label was in phosphatidylinositol 4‐phosphate and phosphatidylinositol 4,5‐bisphosphate. Other lipids labeled included phosphatidylserine, phosphatidic acid and some unidentified lipids. A time course (3–36 h) study revealed a gradual decrease in proportion of labeled PI, an increase in proportion of labeled PC and no obvious change in labeled PE. There were no significant differences in phospholipid labeling comparing theno receptorpotential (norpA) visual mutant and wild type under lightvs. dark conditions. However, overall32P labeling was higher in the wild type fed in the light as compared to the dark and tonorpA either in light or dark. This suggests that functional vision facilitates incorporation of label. Differences in phospholipid labeling were observed between young and aged flies, particularly in lysophospholipids and poly‐PI, implicating phospholipase A2 function in recycling. Manipulations such as theouterrhabdomeresabsent andeyesabsent mutants and carotenoid deprivation failed to yield notable differences in phospholipid labeling pattern, suggesting that phospholipids important to vision may constitute only a minor portion of the total labeled pool in the head.