bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of methyl sterculate on oleic acid synthesis in the hen
Authors: Pearson Judith A. , Fogerty A. C. , Johnson A. R. , Shenstone F. S. 
Published: November 2006

AbstractThe enzymic desaturation of saturated fatty acids to monoenes in animals and plants is inhibited by cyclopropene fatty acids, such as sterculic acid. Labeled acetic and stearic acids were administered to laying hens which had received methyl sterculate in the diet for long periods, and the incorporation of the label in the eggs and liver was studied. The egg was used as a “biological trap” to study the metabolism of the hen in relation to its diet. Maximum incorporation of label was observed in the third or fourth egg laid after administration of the labeled compound. Dietary methyl sterculate reduced the incorporation of stearic acid into egg yolk lipids, but the incorporation of acetate was not affected. The formation of oleic acid was inhibited by methyl sterculate irrespective of whether the prescursor was acetate or stearate acid. In laying hens receiving methyl sterculate for long periods, no evidence could be obtained for the biosynthesis of oleic acid by an alternative pathway which did not involve the desaturation of stearic acid. The validity of comparing the ratio of the specific activities of stearic acid and oleic acid in control birds with the corresponding ratio obtained for birds receiving methyl sterculate is questioned, because the sizes of the metabolic pools of the product and precursors may be quite different for the two groups of birds.
Estimate of fatty acid turnover in porcine adipose tissue
Authors: Anderson D. B. , Kauffman R. G. , Benevenga N. J. 
Published: November 2006

AbstractFatty acid turnover in the domestic pig was estimated by measuring the half‐life of linolenic acid depletion in adipose tissue depots which had been made abnormally high in linolenic acid by feeding large quantities of linseed oil. The measured half‐life of linolenate in 8‐ to 12‐month‐old pigs was 300 days. The apparent half‐life of linolenate in muscle lipids was less than that of subcutaneous backfat.
A comparative study of the lipids of chylomicron membrane and fat core and of the lymph serum of dogs
Authors: Huang T. C. , Kuksis A. 
Published: November 2006

AbstractThoracic lymph was collected from 13 dogs fed corn oil and butterfat. The chylomicrons were isolated by centrifugation. The lipid composition of the fat core and the membrane of the chylomicron was compared to that of the surrounding lymph serum. The fat cores contained 90–96% triglyceride, 0.7–1.9% free cholesterol, 0.2–0.5% steryl ester, 0.9–3.5% free fatty acid and 1.4–6.1% diglyceride, but no phospholipid. The lipids of the membranes contained 58–75% phospholipid, 20–35% triglyceride, 2–5% free cholesterol, 1–2% free fatty acid, and 2–3% diglyceride, but little or no steryl ester. The membrane phospholipids were made up of 70–90% lecithin, 5–20% phosphatidyl ethanolamine, and 1–3% each of lysolecithin and sphingomyelin. The lymph serum contained 24–47% of total lipid as phospholipid, of which 70–92% was lecithin; the phosphatidyl ethanolamine, lysolecithin and sphingomyelin also present contributed 1–10% each. The neutral lipids of the lymph serum contained 49–75% triglyceride, 2–15% free cholesterol, 6–23% esterified cholesterol, 10–33% free fatty acid and 1–6% diglyceride.Alterations in dietary fat, or plant sterol supplementation led to lesser changes in the lipids of the chylomicron membranes than in the lipids of any other lymph fraction. The least variation was seen in the phospholipids.
The enzymic synthesis of ganglioside: I. Brain uridine diphopphate D‐galactose: N‐acetyl‐galactosaminyl‐galactosyl‐glucosyl‐ceramide galactosyl transferase
Authors: Yip Morris C. M. , Dain Joel A. 
Published: November 2006

AbstractAn enzyme which catalyzes the transfer of galactose from UDP‐galactose to galNAc‐gal‐glc‐ceramide is described. The enzyme is found mainly in the nervous tissue of tadpole (Taylor and Kollros stage 17), adult frog, adult and 8 day old rat. The enzymic activity is localized in the 11,500 xg, 20,000 xg and 100,000 xg particles. The UDP‐galactose: galNAc‐gal‐glc‐ceramide from the particles by treatment with sodium desoxylcholate and Triton X‐100. The pH optimum for the solubilized enyme is between 6.8 and 7.0 in cacodylate buffer, and the Km is 4.25 ×10−5 M. The enzymic reaction is proportional to time for 4 hr and to the amount of protein added. The product of the transferase reaction, using galNAc‐gal‐glc‐ceramide. A pathway for the biosynthesis of brain gangliosides requiring UDP‐galactose: galNAc‐gal‐glc‐ceramide galactosyl transferase is proposed.
Gas chromatographic analysis of the dimethylhydrazones of long chain aldehydes
Authors: Johnson C. B. , Pearson A. M. , Dugan L. R. 
Published: November 2006

AbstractLong chain saturated and unsaturated aldehydes, prepared by the partial reduction of the corresponding fatty acid phenyl esters with lithium tri‐t‐butoxyhydroaluminate, were converted quantitatively to their dimethylhydrazones. Dimethyl acetals and 1,3‐dioxolanes were prepared from the dimethylhydrazones. The dimethylhydrazones were then separated from the corresponding aldehydes by gas liquid chromatography on a semipolar column. Fatty acids were readily separated quantitatively from fatty aldehydes by formation of dimethylhydrazones of the aldehydes followed by an alkaline extraction of the reaction mixture prior to gas chromatography. A method for analysis of fatty acids and aldehydes from plasmalogens is described.
Metabolism of 1‐14C‐methyl linoleate hydroperoxide in the rabbit
Authors: Findlay G. M. , Draper H. H. , Bergan J. G. 
Published: November 2006

AbstractThe metabolism of 1‐14C‐methyl linoleate hydroperoxide (1‐14C‐MLHP) by the rabbit was investigated. Administration of 1.1–1.9 mg of 1‐14C‐MLHP by ear vein injection proved lethal to four of the nine experimental animals. After 2 hr the lungs and liver contained 3.3% and 7.2%, respectively, of the dose. This radioactivity was found to be associated primarily with intact 1‐14C‐MLHP. The triglycerides from these tissues also contained14C‐trienoic and14C‐dienoic fatty acids. Of the dose, 68% was recovered as14CO2 in 2 hr compared to 39% after 1‐14C‐methyl linoleate injection. The triglycerides from kidney adipose tissue contained a small amount of14C‐hydroxy fatty acid, providing confirmation of previous evidence for the presence of a fatty acid hydroperoxide reductase in animal tissues.
Effects of pH, concentration and aging on the malonaldehyde reaction with proteins
Authors: Shin Bak C. , Huggins John W. , Carraway Kermit L. 
Published: November 2006

AbstractMalonaldehyde, a major product of unsaturated lipid oxidation, reacts with enzymes to cause inactivation, fluorescence production and crosslinking. The pH dependence for each of these reactions shows a different optimum. Investigation of the stability of malonaldehyde shows that it undergoes decomposition which is dependent on time, reagent concentration and pH. The products resulting from this decomposition are also capable of causing enzyme inactivation and fluorescence production.
Sulfatide biosynthesis by intact microsomes and triton extracts of normal and “Quaking” mouse brain
Authors: Kanfer Julian , Stein Marcia , Shriver Center E. K. 
Published: November 2006

AbstractMicrosomes from “Quaking” mice were unable to catalyze the transfer of35S from PAP35S to ceramide galactoside to form sulfatide. However Triton X‐100 extracts were found to possess this activity.
Circadian rhythm of fatty acid desaturation in mouse liver
Authors: Actis Dato Sara M. , Catala Angel , Brenner Rodolfo R. 
Published: November 2006

AbstractA study was made of the diurnal changes in liver microsomal desaturation of labeled stearic, linoleic and α‐linolenic acids to oleic, γ‐linolenic and octadeca‐6,9,12,15‐tetraenoic acids, respectively. C3H‐S mice were used and were exposed to light‐dark cycles. A circadian rhythm was observed for stearic acid desaturation, and a different one for linoleic acid. Linoleic and α‐linolenic desaturation had similar responses in the day cycle. This would indicate that different mechanisms control the oxidative desaturations of the fatty acids in the 9 and 6 carbons. The fatty acid composition of the whole liver and liver microsomes also showed variations. Remarkable oscillations were observed for stearic and oleic acids. Neither the total protein synthesis nor the free fatty acid concentration in the microsomes followed a rhythm parallel to the desaturation of the studied fatty acids. The injection of cycloheximide 4 hr before measuring the desaturation modified the circadian variation of both the 9 and 6 desaturations. The modification induced by cycloheximide was considered to indicate that both variations are related to the synthesis of specific proteins but not to that of a degradative or inhibitory protein.
Occurrence of ethanolamine‐ and choline‐containing plasmalogens in adipose tissue
Authors: Grigor M. R. , Moehl Anita , Snyder Fred 
Published: November 2006

AbstractAnalysis of phospholipids in porcine, bovine and rat adipose tissue revealed a relatively high level of plasmalogens (O‐alk‐1‐enyl lipids). About 50% of the ethanolamine phospholipids in the pig and beef samples consisted of alk‐1‐enylacylglycerophosphorylethanolamine, and the corresponding value for the rat sample was near 35%. In the ethanolamine and choline phospholipid fractions, theO‐alk‐1‐enyl moieties were almost exclusively 16∶0, 18∶0 and 18∶1, whereas the acyl moieties had chain lengths ranging from 16 to 22 carbon atoms with a high degree of unsaturation.
Effect of dietary vitamin C on adrenal cholesteryl ester content in the guinea pig
Authors: Wilbur Valerie A. , Walker Brian L. 
Published: November 2006

AbstractMale guinea pigs fed a vitamin C‐deficient diet for 3 weeks had lower concentrations of cholesteryl esters in their adrenals than did control animals fed the recommended intake of the vitamin. Not all esters were affected to the same degree, and the fatty acid profiles of the esters from control and deficient guinea pigs differed; there was proportionately more palmitic and linoleic acids and less docosatetraenoic acid [22∶4 (n−6)] in the deficient guinea pig adrenal esters. [Fatty acids are designated as X∶Y (n−Z), where X and Y are the numbers of carbon atoms and olefinic bonds in the acid and Z is the number of carbon atoms after the terminal olefinic bond.] A 100‐fold excess of vitamin C in the diet also resulted in lower concentrations of adrenal cholesteryl esters than did the control diet, but they were not as low as in the deficient animals. Fatty acid profiles were similar for esters from control and excessively supplemented guinea pigs. Vitamin C deficiency apparently imposes a long term stress which results in a depletion of adrenal cholesteryl esters, possibly specific esters, to meet the requirements for glucocorticoid synthesis.
Hydrolysis of biliary phospholipids in the upper small intestine of the chick
Authors: Sklan David , Budowski Pierre 
Published: November 2006

AbstractChick endogenous phospholipids were doubly labeled by an intravenous injection of [32P] phosphate and [1‐14C] oleic acid, and the free fatty acid and phospholipid fraction of gall bladder bile and in contents of upper small intestine were analyzed 4 days later. There was evidence of hydrolysis of biliary phosphatidylcholine to lysophosphatidylcholine in the duodenum and jejunum, but this did not account for the pronounced increase in the14C radioactivity of the free fatty acids relative to the32P phospholipid radioactivity between bile and upper intestinal segments. It is suggested that phosphatidylcholine is largely absorbed in the duodenum of the chick while the remainder is progressively hydrolyzed and absorbed.
Arylsulfonate esters as hypocholesteremic agents: III. Mechanism of action studies
Authors: MacNintch J. E. , Harris R. A. , McLean Grogan W. , Villemez C. L. , Quackenbush F. W. 
Published: November 2006

AbstractThe mechanism responsible for the hypocholestermic action of arylsulfonate esters of long chain fatty alcohols has been studied with rats fed either normocholesteremic or hypercholesteremic (1% cholesterol plus 0.5% glycocholate) diets. Linoleyl tosylate is more effective in lowering plasma and liver cholesterol levels of rats on the hypercholesteremic diet than several other hypocholesteremic agents tested. Linoleyl tosylate does not redistribute cholesterol to extrahepatic tissues nor inhibit hepatic cholesterol biosynthesis. Linoleyl tosylate is not effective in counteracting Tritoninduced hypercholesteremia nor in lowering plasma cholesterol levels of the suckling rat. Linoleyl tosylate increases the fecal elimination of dietary [4‐14C] cholesterol and prevents its accumulation in blood and liver. Oleyl p‐(n‐decyl) benzene sulfonate also prevents the apparent absorption of [26‐14C] cholesterol from the gastrointestinal tract. Linoleyl tosylate increases the fecal excretion of neurtal sterols but not of bile acids. The results indicate that the arylsulfonate esters of long chain fatty alcohols lower body cholesterol levels by inhibiting cholesterol absorption from the gastrointestinal tract. Exactly how absorption is inhibited is not clear, but linoleyl tosylate was found to stimulate the activity of cholesteryl esterase prepared from the intestinal mucosa.
The occurrence and distribution of furan fatty acids in spawning male freshwater fish
Authors: Glass Robert L. , Krick Thomas P. , Olson Daniel L. , Thorson Roxanne L. 
Published: November 2006

AbstractFuran fatty acids (F acids) have been found in the livers and/or testes of 20 species, representing 9 families of male freshwater fish. In 9 species they are major components of the lipids while in the remaining 11 species they occur to a much lesser extent. The F acids in some species reach a maximum concentration in the testes lipids, and minimum liver lipid concentration, at spawning. In all species in the testes, the F acids are confined almost exclusively to the triglyceride fraction while, in the liver lipids, they are found, in order of decreasing concentration, in the cholesteryl esters, the triglycerides, and the phospholipids. In the lipids of many individuals F6 12,15‐epoxy‐13,14‐dimethyleicosa‐12,14‐dienoic acid, is the major fatty acid present. It is presumed that these acids perform some as yet unidentified metabolic function. Isolation technology and identification of F acids by a specific thin layer chromatographic spray reagent are discussed.
Studies on long chaincis‐ andTrans‐acyl‐CoA esters and acyl‐CoA dehydrogenase from rat heart mitochondria
Authors: Korsrud G. O. , Conacher H. B. S. , Jarvis G. A. , Beare‐Rogers J. L. 
Published: November 2006

AbstractThe β‐oxidation of long chain fatty acids was investigated in a preparation of rat heart mitochondria. The acyl‐CoA esters of thecisandtransisomers of Δ9‐hexadecenoic, Δ9‐octadecenoic, Δ11‐eicosenoic, and Δ13‐docosenoic acids were prepared. Rates of the acyl‐CoA reaction were determined with an extract from rat heart mitochondria. The apparent Michaelis constant (Km) and maximum velocity (Vmax) were calculated for each substrate. In general, apparent Vmaxvalues decreased with increasing chain length of the monoenoic substrates. Reduced activity of acyl‐CoA dehydrogenase with long chain acyl‐CoA esters could have contributed to accumulation of lipids in hearts of rats fed diets containing long chain fatty acids.
Lipid metabolism in plasma, liver, and adipose tissue of rats with experimental chronic nephrotic syndrome
Authors: Morin Robert J. , Davidson Warren D. , Rorke S. Joan , Guo Luke S. S. 
Published: November 2006

AbstractPlasma, liver, and adipose tissue lipid composition and synthesis from [1‐14C] acetate were studied three months following induction of nephrotic syndrome in rats by injection of antiglomerular basement membrane protein. Plasma triglyceride concentrations and specific radioactivities were elevated, and the triglycerides contained increased proportions of oleic acid. Plasma cholesterol and phospholipid concentrations were also increased, but free fatty acid levels were not. Liver triglyceride concentrations were decreased and incorporation of [1‐14] acetate into liver triglycerides was also depressed below that of normal controls. Nephrotic rat liver triglycerides contained a higher proportion of oleic acid and lower arachidonic acid than did controls. Incorporation of [1‐14C] acetate into adipose tissue lipids of the nephrotic rats was increased, and the proportion of palmitic acid was decreased. In the chronic nephrotic rat, the major source of the increased plasma triglycerides may be fatty acids mobilized from adipose tissue stores.
Preparation of fucosterol from giant kelp
Authors: Shimadate T. , Rosenstein F. U. , Kircher H. W. 
Published: November 2006

AbstractCommercial extraction of alginic acid fromMacrocystis pyrifera leaves a residue that is a good source of fucosterol, 5,24(28)E‐stigmastadien‐3β‐ol. The isolation and purification of this sterol is described.
Pulmonary surfactant: Distribution of lipids, proteins and surface activity in ultracentrifugation of rabbit pulmonary washing and derived fractions
Authors: Colacicco Giuseppe , Ray Apurba K. , Buckellew A. R. 
Published: November 2006

AbstractLavage from normal adult rabbit lung and two known derived fractions, Fraction T and Fraction S, were subjected to either differential ultracentrifugation in 1.090 g/ml KBr or sucrose density gradient ultracentrifugation; the surface activity of the lipid extract of selected fractions was measured. In differential ultracentrifugation, the three starting materials yielded a pellicle containing > 85% of the phospholipid with <1% protein. In sucrose density gradient ultracentrifugation: pulmonary washing, containing about equal weights of phospholipid and protein (60% albumin, 20% sIgA, 10% IgG, 10% minor proteins), produced one single band at density 1.040, containing virtually one single protein, namely >80% of the total sIgA (protein T) and up to 60% of the total phospholipid, whereas all the albumin and IgG were found at very low densities, 1.010 and 1.025, respectively; Fraction T, having nearly equal weights of one signle protein, sIgA, and phospholipid, produced two contiguous bands at densities 1.059 and 1.078, totalling >85% of its phospholipid and <25% of its protein, the balance of which was found free of phospholipid at densities 1.020 to 1.050; comprising >80% of the phospholipid and <20% of the protein of pulmonary washing, Fraction S yielded two small bands at densities 1.028 and 1.044 and a major band at d=1.059. In surface activity measurements: when the total lipid extract of the bands from the sucrose density gradient ultracentrifugation was spread as a film, in spite of similarly high dipalmitoyl lecithin contents (about 70% palmitoyl lecithin contents (about 70% palmitoyl residue), the lipid of the band of Fraction T and that of the high density band of Fraction S were very active (γmin=0); whereas the lipid of the band of pulmonary washing and that of the lowest density band of Fraction S were not active,γmin being 18 dyne/cm and 21 dyne/cm, respectively. This wokk brings forth three major conclusions. First, under conditions which are used to isolate serum lipoproteins, no lipoprotein was obtained from either of the three surfactant fractions and most of the lipid was found virtually free of protein. Second, the isopicnic equilibrium of a given ultracentrifugation fraction varied with the molecular structure of its constituents and could not be accounted for by the latter's average densities; instead, major roles must be player by particle geometry and their water contents. Third, although the various lipid samples contained the same quantities of palmitoyl residues (70%), the surface activities varied with the physical state of the lipid, method of assay, and some other undefined factors.
Effects of ethionine and phenobarbital on the phosphatidylcholines of rat liver
Authors: Dyer R. A. , Klopfenstein W. E. 
Published: November 2006

AbstractThe diglyceride species of phosphatidylcholines from livers of male rats after treatment of the animals with ethionine (1 mg/g divided among 4 doses 2 hr apart), phenobarbital (80 mg/kg each day for 3 days), or a combination of the two drugs were determined using gas chromatography. Ethionine treatment greatly elevated the diene species (significant at the 0.005 level for 34∶2 and 0.001 level for 36∶2). Phenobarbital treatment had no significant effect on the quantity of 34∶2 but slightly increased that of 36∶2 (significant at the 0.05 level). Both drugs caused relative decreases in the quantities of 38∶4 (significant at the 0.001 level for ethionine and at the 0.01 level for phenobarbital). Ethionine decreased the content of 36∶4 (significant at the 0.01 level) while phenobarbital treatment did not produce a significant effect on this fraction. Thus, while ethionine produced marked effects on the quantities of the various molecular species, the effects of phenobarbital were less dramatic. Combined treatment with both drugs generally produced levels of species similar to those produced by ethionine alone.
Substrate metabolism in the perfused lung: Response to changes in circulating glucose and palmitate levels
Authors: Shaw Mary E. , Rhoades Rodney A. 
Published: November 2006

AbstractThe effects of circulating levels of glucose and palmitate in the isolated perfused rat lung were investigated. Rat lungs were perfused for 1.5 hr with washed bovine erythrocytes (15% hematocrit) in Krebs‐Henseleit bicarbonate buffer containing 5 g% bovine serum albumin. Glucose uptake in the perfused lung varied directly with circulating glucose concentration. Lactate production was affected proportionately more by high glucose levels than by low concentrations. Pyruvate production was decreased by both low glucose and palmitate concentration in the circulating medium. Oxidation of glucose to CO2 was depressed by low glucose and by high palmitate concentrations. Glucose incorporation into lung lipids was more strongly influenced by glucose concentration than by circulating palmitate levels. These data indicate acute changes in circulating levels of glucose and palmitate alone can act to either inhibit or stimulate glycolysis, glucose oxidation, and lipid synthesis in the perfused lung.