bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of feeding ethyl‐dihomo‐γ‐linolenate on rabbit renomedullary lipid composition and prostaglandin production in vitro
Authors: Knapp H. R. , Oelz O. , Whorton A. R. , Oates J. A. 
Published: November 2006

AbstractFeeding the ethyl ester of dihomo‐γ‐linolenic acid for 25 days to rabbits resulted in increased PGE1 (20to30‐fold) and PGE2 (1.5‐fold) output by a hormone responsive, in vitro, renal papilla preparation. The relative amount of PGE1 increased from <5% of PGE2 in controls to 25–35% of PGE2 in the papillae of 20∶3ω6‐supplemented animals. During the study renomedullary triglycerides in the 20∶3ω6‐supplemented animals increased 2.8‐fold compared to animals fed an equal amount of a control fatty acid mixture, and in addition to a marked enrichment in 20∶3ω6, also contained increased proportions of 20∶4ω6 and longer chain polyenes. The increase in triglyceride content found in the renal medulla was not seen in the renal cortex or liver. There was no increase in renomedullary phospholipid content during the study, and phopholipids of treated animals contained increased proportions of 20∶3ω6 and 20∶4ω6, but not longer chain polyenes. The results indicate that enriching the prostaglandin precursor pool by feeding 20∶3ω6 can alter the type and amount of prostaglandin released by the renal papilla, at least in vitro. Also, the selective changes in amount and long chain polyene content of renomedullary triglycerides during the study suggest some special functions for this lipid class in prostaglandin precursor metabolism. *** DIRECT SUPPORT *** A00M6131 00010
Synthesis and characterization of [1‐13C]‐and d8‐arachidonic acid
Authors: Do Un Hoi , Sundaram M. G. , Ramachandran S. , Bryant Robert W. 
Published: November 2006

AbstractMethyld8‐ and [1‐13C] 5,8,11,14‐eicosatetraenoate (arachidonate) were prepared from a common synthetic precursor, 4,7,10,13‐nonadecatetrayn‐1‐ol. The purified products were characterized by gas chromatography‐mass spectrometry. Mass spectra oft‐butyldimethylsilyl esters ofd8‐and [1‐13C]‐arachidonic acid showed a most intense [M‐57]+ peak at high mass. The isotopic purity of methyl [1‐13C] arachidonate was 99% and that of methyld8‐arachidonate was 56%. Whend8‐arachidonic acid was prepared by direct deuteration of 5,8,11,14‐eicosatetraynoic acid, the isotopic purity of the sample was 86%.
Molecular species composition of phosphatidylcholines during the development of the avian embryo brain
Authors: Gonzalez‐Ros Jose M. , Ribera A. 
Published: November 2006

AbstractA comparative approach has been used to investigate the molecular species composition of phosphatidylcholine (PC) and its age variation throughout several developmental stages of chick and duck embryo brains. The brain PC consist of 15 major molecular species which do not undergo appreciable variation in their relative abundance either during embryonic development or between equivalent stages of maturation in the 2 avian species. In fact, a highly invariable molecular architecture of PC is shown in the developing organ. Molecular species containing saturated or monounsaturated fatty acids were dominant in all stages of development of the avian embryo brain. Among these molecular species, 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphocholine, 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine accounted for 75–80% of the total PC.
Comparisons of monoacylglycerols and diacylglycerols of varying fatty acid composition as substrates for the acylglycerol kinase(s) of rat brain
Authors: Bishop H. H. , Strickland K. P. 
Published: November 2006

AsstractThe properties of diacylglycerol and monoacylglycerol kinase activities present in 90,000 x g pellet and 90,000 × g supernatant fractions from rat brain were examined and compared. Of the properties examined, time course (linear for 10 min), enzyme concentration, pH optimum (7.4–7.5), varying ATP (5 mM) and Mg2+ (10 mM) concentrations all showed similar optima for both activities. The optima for acylglycerol (5 mM for diacylglycerols; 3 mM for monoacylglycerols) and deoxycholate concentrations (0.1% for diacylglycerol kinase; 0.03% for monoacylglycerol kinase) differed slightly. Examination of the subcellular distribution for these activities also showed a similar pattern. All fractions showed significant activities, but the most was in the supernatant fraction. The similarities in properties and localization of the 2 kinase activities suggest a single enzyme may function. On this assumption, an extensive study using mono‐ and diacylglycerols of varying fatty acid composition gave the following results: (a) acylglycerols with the same fatty acid present showed increasing activity in the order: 1‐monoacylglycerol, 2‐monoacylglycerol and 1,2‐diacylglycerols; (b) when saturated fatty acids were present the order of decreasing activity varied directly with increasing chain length for C10→C20; (c) when one or more unsaturated fatty acids were present good activities resulted, but no clear pattern emerged, although acylglycerols with18∶1 and18∶3 fatty acids were more active than those with18∶2 and20∶4 fatty acids. These patterns do not support a role for this kinase in producing phosphatidic acids or lyso phosphatidic acids of the correct composition to act as precursors for the de novo synthesis of the predominant 1‐stearoyl, 2‐arachidonoyl molecular species of phosphatidylinositol.
Dietary arachidonic acid reduces fatty liver, increases diet consumption and weight gain in ethanol‐fed rats
Authors: Goheen Steven C. , Larkin Edward C. , Manix Marcia , Rao G. Ananda 
Published: November 2006

AbstractWe fed young male Sprague‐Dawley rats for 4 wk ad libitum liquid diets containing 34% of the calories as ethanol and 35% as fat with (AA+) and without (AA−) arachidonic acid (20∶4). Additional rats in the control groups were fed similar diets made isocaloric with dextrose with (CA+) and without (CA−) 20∶4. The liver triglyceride (TG) content of rats in the AA+ group was reduced ca. 3‐fold over that of rats in the AA‐group. The diet consumption and body wts of rats in the AA+ group were significantly greater than those of rats fed alcohol without the 20∶4 supplement (AA−). Also livers from rats in the AA+ group were as large as those from rats in control groups (CA+, CA−) and ca. twice as large as those from rats in the AA‐group. The fatty acid composition of liver TG in rats fed the alcohol diet was similar to that of dietary fat. Levels of 20∶4 and docosatetraenoic acid (22∶4) in liver TG fatty acids from rats fed diets without arachidonate (AA−, CA−) were low (trace to 1.6%). After ingestion of arachidonic acid, 20∶4 increased to ca. 10% and 22∶4 to ca. 5%. The content of liver phospholipids was higher in livers of rats fed ethanol (AA−) than in those of controls (CA−).
Distribution of high density and other lipoproteins in selected LRC prevalence study populations: A brief survey
Authors: Rifkind Basil M. , Tamir Israel , Heiss Gerardo , Wallace Robert B. , Tyroler Herman A. 
Published: November 2006

AbstractSelected lipid and lipoprotein data from the Lipid Research Clinics (LRC) Prevalence Study are presented, with particular emphasis given to high‐density lipoprotein (HDL) values. Cross‐sectional age‐and sex‐specific mean values are shown for 7007 white participants in the ten North American LRCs. Comparisons are drawn for males and females (including the pediatric group) and for females using or not using sex hormones. The US‐USSR Collaborative Program is summarized, and selected comparisons are noted for the Soviet and United States samples.
Fatty acids of cerebrosides in different regions of the developing foetal brain
Authors: Rao P. Srinivasa 
Published: November 2006

AbstractThe fatty acid composition of cerebrosides of developing foetal human brain and regional variations, if any, during intrauterine life were studied. While palmitic and stearic acids were the predominant normal fatty acids throughout intrauterine life, long chain fatty acids, like lignoceric and nervonic acids, which were low at early gestational ages, rapidly accumulated at term. Regional differences were observed in the concentrations of long chain normal fatty acids especially at term. Medulla oblongata showed a greater accumulation of long chain fatty acids as compared to the cerebellum and cerebrum. The distribution of 2‐hydroxy fatty acids in different regions showed a pattern predominantly that of long chain carbon units, even at 34 wk of foetal life. A higher ratio of lignoeric to stearic acid in the case of normal fatty acids, probably indicative of chain elongation, was also evident in the case of medulla oblongata and cerebellum as compared to the cerebrum. The significance of these qualitative alterations in relation to rapid growth of brain prior to term and the process of myelination has been discussed.
Comparative effects of (−)‐hydroxycitrate and (+)‐allo‐hydroxycitrate on acetyl CoA carboxylase and fatty acid and cholesterol synthesis in vivo
Authors: Triscari Joseph , Sullivan Ann C. 
Published: November 2006

Abstract(−)‐Hydroxycitrate and (+)‐allo‐hydroxycitrate were investigated for their effects on lipid synthesis in vivo under conditions of either high carbohydrate feeding or 24 hr fasting. Changes in rates of lipid synthesis resulting from the oral administration of these compounds were monitored with the use of radiolabeled H2O, alanine, and acetate. In the fed rat, (−)‐hydroxycitrate significantly reduced the incorporation of H2O and alanine into fatty acids and cholesterol. An increased incorporation of labeled H2O into fatty acids but no change in cholesterol synthesis in the fasted rat suggested that (−)‐hydroxycitrate may be an activator of acetyl CoA carboxylase. With (−)‐hydroxycitrate administration, acetate incorporation into fatty acids and cholesterol was subject to pool dilution effects under fed or fasted states. (+)‐allo‐Hydroxycitrate was ineffective in modulating the rates of fatty acid synthesis under either nutritional condition. Both (−)‐hydroxycitrate and (+)‐allo‐hydroxycitrate were shown to be in vitro activators of acetyl CoA carboxylase, the former being a much stronger activator than the latter. Thus, stereospecificity of the hydroxycitrate isomers was demonstrated in both the inhibition of lipid synthesis (previously shown to occur at adenosine triphosphate citrate lyase) and the stimulation of fatty acid synthesis (possibly occurring at acetyl CoA carboxylase).
Erucic acid and phospholipids of newborn rat heart cells in culture
Authors: Rogers C. G. 
Published: November 2006

AbstractErucic acid (Δ13‐docosenoic acid), labeled with14C in the 1‐or 14‐position, was incorporated into fetal calf serum and fed to beating, neonatal rat myocardial cells in culture. Uptake of the docosenoic acid during the first 6 hr of incubation was 41 nM/hr/mg protein in 7‐day old cells and 29 nM/hr/mg protein in 14‐day old cells. Fifty‐seven percent of the14C‐activity was taken up from the medium in 24 hr, of which 77% was in the cells and 23% was unaccounted for. Of the14C‐activity taken up, 26% was in extractable lipid, with two‐thirds in neutral lipid and one‐third in phospholipid. Within the neutral lipid fraction, 88% of the14C‐activity was present in triglycerides; while in phospholipids, 66% of the14C‐activity was in phosphatidylcholine (PC); 14% in phosphatidylethanolamine (PE); 6% in sphingomyelin (SPH) and 1% or less in cardiolipin (DPG). PC had the highest specific activity, followed by SPH and PE. The specific activity of PE was one‐half that of SPH when the14C‐erucic acid substrate was labeled at the carboxyl position, but increased to equal that of SPH when the substrate was labeled at the double bond. The fatty acids of PC, PE, and SPH were influenced by erucic acid in the growth medium, but the amounts of each phospholipid were not affected. It is proposed that the altered fatty acid composition associated with incorporation of erucic acid or its metabolites into PC, PE, and SPH may affect integrity and function of heart cell membranes.
Effects of dietary antioxidants on in vivo lipid peroxidation in the rat as measured by pentane production
Authors: Downey Jeanne E. , Irving Dennis H. , Tappel Al L. 
Published: November 2006

AbstractThe hypothesis that pentane is an in vivo product of lipid peroxidation was confirmed by a study of the effects of a nonbiological antioxidant on pentane production in rats fed a diet deficient in vitamin E and supplemented with 0.01% N,N′‐diphenyl‐p‐phenylenediamine (DPPD). Seven rats were fed a vitamin E‐deficient diet starting at 3 wk of age. After 5 wk, 0.01% DPPD was added to the diets of three rats (group DPPD) while the diet of the other four rats remained unchanged (group OE). Within 2 wk of the diet change, rats in group DPPD exhaled 65% less pentane than rats of the same age in group OE. After 5 wk of being fed the DPPD‐supplemented diet, rats in group DPPD were again fed the basal vitamin E‐deficient diet; within 3 wk, these rats produced pentane levels similar to those of rats in group OE. The effects of vitamin E depletion and repletion on in vivo lipid peroxidation in rats were also studied. Three groups of three rats each were initially fed a vitamin E‐deficient diet starting at 3 wk of age. After 8, 8, and 5 wk of being fed this diet, the three groups were fed diets supplemented with 3.3 (group 0→3.3E), 11 (group 0→11 E), and 200 (group 200E) i.u. vitamin E acetate/kg diet, respectively. Another group of three rats (group 11 E) was fed a diet supplemented with 11 i.u. vitamin E/kg starting at 3 wk of age for the duration of the study. There were significant decreases in pentane production by rat groups 0→3.3E, 0→11E, and 200E within 2 wk of the change to the vitamin E‐supplemented diets. After about 5 wk of being fed their respective vitamin E‐supplemented diets, pentane breath levels had stabilized. Breath pentane levels were inversely proportional to the log of dietary vitamin E concentration.
Cerebral prostaglandin synthesis during the dietary and pathological stresses of essential fatty acid deficiency and experimental allergic encephalomyelitis
Authors: Weston Patricia G. , Johnston Patricia V. 
Published: November 2006

AbstractRats of the Lewis strain were fed diets adequate or deficient in essential fatty acids (EFA). At 70–80 days of age experimental allergic encephalomyelitis (EAE) was induced using adjuvants containing eitherMycobacterium butyricum orMycobacterium tuberculosis H37Ra. When the formerMycobacterium was used, the incidence of EAE was greater in the EFA‐deficient than in EFA‐adequate controls; but when the rats challenged withM. tuberculosis, the incidence of the disease was the same in both dietary groups. Brain slices from EFA‐deficient rats had a marginally depressed synthesis of prostaglandin F (PGF) compared to that of controls. Immunochallenge with adjuvant alone or adjuvant plus antigen tended to depress further PGF synthesis by brain slices from EFA‐deficient rats and significantly depressed synthesis by slices from rats receiving adequate EFA. Whether or not rats were paralyzed had no effect on PGF synthesis when the diet was adequate in EFA, but a significant difference was seen in the EFA‐deficient group. The results indicate a possible role for PGF synthesis in the degree of susceptibility of the rats to EAE under different dietary regimens.
Effect of pentadecan‐2‐one on lipid metabolism in HeLa cells
Authors: Naccarato W. F. , Gilbertson J. R. 
Published: November 2006

AbstractHeLa cells exposed to trace amounts of pentadecan‐2‐one showed changes in metabolism of 1‐14C‐palmitate. These changes consisted of an increased incorporation of radioactivity into the triglycerides and free fatty acids and a decreased14C incorporation into the ether moiety of alk‐1‐enyl acyl phosphoglycerides. Chemical analysis of the several lipid fractions showed a threefold increase in triglyceride content but no change in the amount of alk‐1‐enyl acyl or diacyl phosphoglycerides in the treated cells. Pentadecan‐2‐one added to the culture medium apparently gains entrance to the cell since both pentadecan‐2‐one and pentadecan‐2‐ol were detected in the ketone‐treated cells and their culture medium.
Cholesterol and repair processes in arteriosclerosis
Authors: Kaunitz Hans 
Published: November 2006

AbstractThe high cholesterol content of the atheroma and the correlation between elevation of the serum cholesterol and myocardial infractions gave rise to the lipid theory of arteriosclerosis, which assumes that cholesterol induces arteriosclerotic lesions and that its reduction counteracts their development. However, many facts contradict this theory. Therefore, a new hypothesis has been based on the high cholesterol content of old pathological lesions of granulomatous nature and the similarity of atheromata to granulomas. In the latter, a complicated tissue containing a high percentage of cholesterol is deposited in response to the injurious agent, which becomes walled off by this tissue. Thus, cholesterol forms part of a protective mechanism, a hypothesis compatible with the known facts about the relationship of cholesterol to arteriosclerosis.
Hyperlipidemia and premature arteriosclerosis
Authors: Smith Frank Rees 
Published: November 2006

AbstractIn the last decade, understanding of the relationship between plasma lipoprotein concentrations and arteriosclerosis has advanced considerably. Prospective and case‐control epidemiologic studies in the general population have established a direct correlation between low density lipoprotein and an inverse correlation between high density lipoprotein concentrations and the risk of coronary disease. Detailed studies of patients and families with genetic hypercholesterolemia, hypertriglyceridemia, and combined hypercholesterolemia hypertriglyceridemia have identified subpopulations at particular risk. Skin fibroblast lines from patients with genetic hyperlipidemias have been used to provide important new information on the regulation by plasma lipoproteins of cellular cholesterol metabolism. We are entering a phase of investigation where epidemiological and biochemical data supplement each other in such a way that the old hypothesis linking plasma lipids to atherosclerosis has new life.
The development of coronary thrombosis following myocardial infarction
Authors: Branwood A. Whitley 
Published: November 2006

AbstractOne hundred twenty‐one patients who died from myocardial infarction were studied. Occlusive coronary artery thrombosis was present in 32%. In 68% of these, the infarct developed first. Factors inducing thrombus formation include fall in systemic blood pressure, alteration of blood flow, shock, and size of infarct. Factors inducing infarction, apart from hypoxia, may be stress, altered cell membrane permeability, and increased catecholamines.
Effect of catecholamines and β‐blockers on linoleic acid desaturation activity
Authors: de Gómez Dumm Irma N. T. , de Alaniz María J. T. , Brenner Rodolfo R. 
Published: November 2006

AbstractThe effect of catecholamines and adrenergic blocking agents on the oxidative desaturation of linoleic acid in rat liver microsomes was studied. Epinephrine (1 mg/kg/body weight) produced a significant decrease on the conversion of [1‐14C]linoleic acid to γ‐linolenic acid. The effect of epinephrine was blocked by single injections of the β blockers propranolol (10 mg/kg body weight) or dichloroisoproterenol 30 min before the hormone treatment. Isoproterenol (100 μg/kg body weight) produced a significant decrease on the activity of the linoleyl‐CoA desaturase. The effect of the catecholamines was postulated to be mediated through β receptors by an enhancement of the intracellular levels of cyclic AMP.
Lipid and alkali extractable fatty acids fromMucor rouxii: Effect of thermal changes in growth environment and age of cells
Authors: Safe S. 
Published: November 2006

AbstractThe lipid levels of the fungusMucor rouxii are affected markedly by both the growth temperature and the age of the cells. Both chloroform‐methanol extractable (fraction I) and alkali extractable (fraction II) fatty acids are present in these cells, and the fraction II/fraction I ratio increased significantly with decreasing growth temperature. This ratio was, however, reasonably constant during the entire growth period at each specific growth temperature. In all cases, the unsaturation index of the fraction II fatty acids was significantly lower than the corresponding value for the fraction I fatty acids. Examination of the unsaturation indeces of the two fractions during the early log‐phase growth period (48 hrs) indicated that the indeces decreased with increasing growth temperature; however, as the age of the cells increased, this relationship changed dramatically. At the end of 144 hrs growth, the unsaturation index for fraction II has reversed its temperature dependance completely, since the index is a maximum at the higher growth temperature. The degree of unsaturation for fraction I is a maximum at 25 C and is lower for cells grown at 15 and 35 C; this relationship is true between 96–144 hr after inoculation.
Lipids of cultured hepatoma cells: IV. Effect of serum and lipid upon cellular and media neutral lipids
Authors: Wood Randall , Falch John 
Published: November 2006

AbstractMinimal deviation hepatoma 7288C cells were cultured in a modified Swim's medium supplemented with decreasing levels of serum, lipid‐free serum, lipid‐free serum plus fatty acids, and other additives. Cellular and media neutral lipid classes were quantitated, the fatty acids of triglycerides and sterol esters analyzed, and the carbon number distribution of triglycerides determined. Cellular triglyceride biosynthesis virtually was inhibited when the medium was supplemented with bovine serum alone. This inhibition was not observed when the medium was supplemented with fetal calf serum alone or mixtures of fetal calf serum and bovine serum. Cells cultivated on medium supplemented with lipid‐free serum plus palmitic or linoleic acids had much lower levels of free and esterified cholesterol. The fatty acid composition of cellular triglycerides and cholesterol esters differed dramatically from the corresponding media lipid classes. Except when linoleic acid was added to the medium, changes in the media serum and lipid levels had only marginal effects upon the fatty acid composition of cellular triglycerides and cholesterol esters. These data, in conjunction with earlier data that showed the media neutral lipid levels did not decrease during cell growth, indicate that these hepatoma cells utilize little or no serum triglycerides and cholesterol esters. Linoleic acid added to the medium dramatically reduced the level of 18∶1 acids in cellular triglycerides and cholesterol esters. Palmitic acid added to the medium did not change the fatty acid compositions significantly. Comparison of experimentally determined and calculated triglyceride carbon number percentages indicated a random distribution of fatty acids in this glyceride. The fatty acid composition of cellular triglycerides was similar to the composition of the cholesterol esters. The lack of characteristic and distinguishable compositions of these two classes that occur in most normal tissues suggests a loss of specificity in the lipid metabolism of this neoplasm at the class level.