bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lipids of cultured hepatoma cells: VII. Structural analyses of glycerolipids in minimal deviation hepatoma 7288C
Authors: Wiegand Rex D. , Wood Randall 
Published: November 2006

AbstractPhosphatidylcholine, phosphatidylethanolamine, and triglycerides were isolated from minimal deviation hepatoma 7288C cells cultured as monolayers to confluency in roller flasks containing Swim's 77 medium supplemented with 5% fetal calf serum, plus 20%, 10%, or 5% bovine serum. Fatty acid distribution at each position of glycerol was determined for the 3 glycerolipid classes, and carbon number distributions of triglycerides and diglycerides derived from phosphatidylcholine and phosphatidylethanolamine were quantitated by high temperature gas liquid chromatography. Fatty acid composition was only marginally affected by the level of bovine serum in the culture medium. Percentage composition of fatty acids esterified at each position of the 3 glycerolipids was different, indicating a nonrandom distribution of acyl groups in triglycerides and the 2 diacyl phosphatides. The carbon number distribution of diglycerides derived from phosphatidylcholine and phosphatidylethanolamine was different, and neither carbon number distribution agreed with the calculated 1‐random, 2‐random diacyl distribution, thus indicating pairing of certain acids in the diglycerides derived from these phospholipid classes. The determined triglyceride carbon number distributions did not show complete agreement with those calculated, assuming a 1‐random, 2‐random, 3‐random type of fatty acyl distribution, suggesting preferential pairing of some acids in this lipid class. The 1‐, 2‐diglycerides derived from phosphatidylcholine, phosphatidylethanolamine, and triglycerides differed, indicating either selectivity in utilization of diglyceride species in biosynthesis of these glycerolipids, or modification of glycerolipids after their initial synthesis.
KCN Inhibition of lipoxygenase in purple, green, and white eggplants
Authors: Flick George J. , Angelo Allen J. St. , Ory Robert L. 
Published: November 2006

AbstractLipoxygenase activity in three cultivars (purple, green, and white) of eggplant,Solanum melongena, were compared. Activity was greatest in the purple and lowest in the white variety. In contrast to reports that NaCN did not inhibit eggplant lipoxygenase, in these studies cyanide completely inhibited the enzyme in all three varieties.
Stimulatory effect of glucose upon triglyceride synthesis from acetate, decanoate, and palmitate by mammary gland slices from lactating mice
Authors: Rao G. Ananda , Abraham S. 
Published: November 2006

AbstractSlices prepared from the mammary glands of lactating mice incorporate only small amounts of (1‐14C) acetate, (1‐14C) decanoate, or (1‐14C) palmitate into lipids. However, when glucose is added to the incubation medium, fatty acid incorporation is stimulated—13‐fold from acetate, 17‐fold from decanoate, and 2‐fold from palmitate. Over 90% of the14C activity in the lipid fraction is in triglycerides. Analysis of fatty acids in the triglycerides showed that almost all of the decanoate and the palmitate were incorporated as intact molecules, while acetate yielded acids of varying chain lengths. The glucose stimulation of triglyceride synthesis is not solely due to its effect upon chain elongation but also could involve glyceride‐glycerol availability, as well as other unknown factors. However, from measurements of the amounts of glycerol 3‐phosphate in the tissue incubated in the presence of palmitate, it would appear that glyceride‐glycerol availability is not rate limiting in triglyceride synthesis.
Cis‐5‐polyenoic acids inLarix leptolepis seed oil
Authors: Plattner R. D. , Spencer G. F. , Kleiman R. 
Published: November 2006

Abstractcis‐5,cis‐9‐Octadecadienoic acid (2.7%) andcis‐5,cis‐9,cis‐12‐octadecatrienoic acid (24.9%) are present in the seed oil ofLarix leptolepis. The double bond positions were identified by ozonolysis and by gas chromatography‐mass spectrometry of methoxy derivatives. Small quantities of branched chain acids of various chain lengths were indicated by gas chromatography. The presence of C17 and C19 branched methyl esters was confirmed by gas chromatography‐mass spectrometry.
The incorporation of orally fed radioactive γ‐linolenic acid and linoleic acid into the liver and brain lipids of suckling rats
Authors: Hassam A. G. , Sinclair A. J. , Cramwford M. A. 
Published: November 2006

AbstractThe incorporation of radioactivity from orally administered γ‐linolenic acid‐1‐14C and linoleic acid‐3H into the liver, plasma, and brain lipids of suckling rats was studied. Significantly more radioactivity from the former compound was incorporated into the liver and brain lipids 22 hr after dosing. The distribution of the radioactivity in the fatty acids of the liver and brain lipids was different for each isotope. Most of the3H was still associated with linoleic acid, whereas most of the14C was in the 20∶3 and 20∶4ω6 fractions. These results suggest that the desaturation of linoleic to γ‐linolenic acid in vivo is a rate‐limiting step in the conversion of linoleic to arachidonic acid.
Inhibition of diplopterol synthesis inTetrahymena pyriformis by a hypocholesteremic compound
Authors: Babiak Z. , Carlisle T. L. , Holmlund C. E. 
Published: November 2006

AbstractThe hypocholesteremic compound, 3β‐(β‐dimethylaminoethoxy)‐androst‐5‐en‐17‐one was earlier shown to inhibit the synthesis of tetrahymanol and two unidentified lipids. It now has been demonstrated that one of the unidentified compounds is diplopterol.
Identification and quantitation of cholanoic acids in hepatic and extra‐hepatic tissues of rat
Authors: Oh Suk Yon , Dupont Jacqueline 
Published: November 2006

AbstractTissues of rats were examined for the presence of cholanoic acids. Quantitation of extraction, deconjugation, and isolation were verified by use of radioactive standards. Identification was made by thin layer and gas liquid chromatographic comparison to standards and mass spectrometry. All tissues examined were found to contain several conjugated cholanoic acids. Liver contained primarily cholic acid and peripheral tissues primarily dihydroxy compounds, mainly hyodeoxycholic acid.
Mass spectrometric determination of positions of double bonds in polyunsaturated fatty acid pyrrolidides
Authors: Andersson Bengt Å. , Christie William W. , Holman Ralph T. 
Published: November 2006

AbstractLow resolution mass spectra of pyrrolidides of isomeric octadecadienoic acids and other polyunsaturated straight chain fatty acids are presented and discussed. The spectra of the pyrrolidides contain mainly ions from the polar part of the molecule and give spectra that are specific for each isomer. The interpretation follows, in most cases, the rule developed for monounsaturated fatty acid pyrrolidides.
Effect of inhibitors and phenobarbital pretreatment upon hepatic lipid peroxidation during protein and riboflavin dietary stress in male rats
Authors: Patel J. M. , Galdhar N. R. , Javalgekar S. Y. , Pawar S. S. 
Published: November 2006

AbstractMale young albino rats divided into three groups were maintained on the following diets. The normal group was maintained on 13% casein, 45% corn starch, 31% sucrose, 6% salt mixture, 4% peanut oil, and 1% vitamin mixture. The low protein group animals recieved only 5% casein, and the riboflavin‐deficient group was fed normal diet, except that the riboflavin was absent from the vitamin mixture and ordinary casein was replaced by 13% vitamin‐free casein. The effects of various inhibitors upon triphosphopyridine nucleotide, reduced form‐linked lipid peroxide formation by the supernatant fraction of liver at 9000 × g from rats fed a normal diet, a low protein diet, or a riboflavin‐deficient diet for 2,4, and 7 weeks were investigated. A significant decrease in triphosphoryridine nucleotide, reduced form‐linked and ascorbate‐induced lipid peroxidation was noticed in rats fed on low protein and riboflavin‐deficient diet. Glutathione inhibited the triphosphopyridine nucleotide, reduced form‐linked lipid peroxidation in rats from all three groups. However, the observed response was variable due to the nature of the diet. The magnitude of inhibition was greater in low protein‐fed animals than in animals from the riboflavin‐deficient and control groups. Cytochrome C inhibited peroxide formation, but the inhibition was greater in rats from the low protein and riboflavin‐deficient groups than in animals from the normal group. Tocopherol exhibited the antioxidant property in all three groups of rats. Deoxycholate inhibited lipid peroxide formation in all the three groups.
Fatty acid synthetase of bovine mammary: Properties and products
Authors: Kinsella J. E. , Bruns D. , Infante J. P. 
Published: November 2006

AbstractFatty acid synthetase purified (20 times) from lactating bovine mammary tissue had an approximate mot wt of 485,000. The enzyme had a high content of acidic and hydrophobic amino acid residues; 62±4 sulhydryl groups and one 4′ phosphopantetheine residue/mole of enzyme. The enzyme was relatively stable when stored (3 mg/ml) in potassium phosphate buffer (250 mM), containing dithiothreitol (5 mM) at −5 C or at −30C or as a lyophilized powder at −30 C. Preincubation at 37 C in presence of dithioltreitol (5 mM) was necessary for obtaining maximum activity at the optimum pH of 6.8. Maximum specific activity of the isolated enzyme was 55 nmoles acetyl‐coenzyme A min−1mg−1 incorporated A min−1mg−1 incorporated into fatty acids. Butyryl‐coenzyme A or acetyl‐coenzyme A (30μM), malonyl‐coenzyme A (65 μM), and nicotinamide adenine dinucleotide phosphate, reduced form (300 μM) were required for optimum fatty acid synthesis. Malonyl‐coenzyme A decarboxylase activity (5 nmoles min−1mg−1) associated with the enzyme permitted fatty acid synthesis in the presence of nicotinamide adenine dinucleotide phosphate, reduced form and malonyl‐coenzyme A. The enzyme utilized acetyl‐coenzyme A, butyryl‐coenzyme A, and hexanoyl‐coenzyme A as primers, with butyryl‐coenzyme A giving the maximum rate of fatty acid synthesis. Apparent Km values of 22,6.7, 3, 22, and 20 μM were obtained for malonyl‐coenzyme A, acetyl‐coenzyme A, butyryl‐coenzyme A, hexanoyl‐coenzyme A, and nicotinamide adenine dinucleotide phosphate, reduced form, The fatty acid synthetase was inhibited by N‐ethylmaleimide, iodoacetamide, and progressively inhibited by increasing concentrations of long chain acyl‐coenzyme A, i.e. palmityl‐coenzyme A and myristyl‐coenzyme A. This inhibition was relieved by bovine serum albumin or β‐lactoglobulin (3 mg/ml). Palmitic acid was the major product of bovine mammary fatty acid synthetase. However, small amounts of fatty acids, 4∶0–14∶0 inclusive, also were synthesized. The pattern of fatty acids was altered by varying malonyl‐coenzyme A to acetyl‐coenzyme A ratios and by increasing the enzyme levels in the assays. At high concentrations of enzyme (0.5 mg/ml), greater amounts of short and medium chain fatty acids were generated.
Electron spin resonance study of serum lipoproteins of salmon (Oncorhynchus kisutch): Structural alterations produced in high density lipoproteins by mercury and cadmium
Authors: Reichert William L. , Malins Donald C. 
Published: November 2006

AbstractHigh denisty lipoproteins from the serum of salmon (Oncorhynchus kisutch), containing a maleimide spin label (4‐male‐imido‐2,2,6,6‐tetramethylpiperidinooxyl), were exposed to HgCl2, CdCl2, and CH3HgCl under physiological conditions. Electron spin resonance spectrometry revealed that HgCl2 and CdCl2 produce significant alterations at sites representing weakly and strongly immobilized label. The observed changes appear to be taking place primarily in the surface architecture. No alterations were found in the normal spectra of high density lipoproteins exposed to CH3HgCl under similar conditions. Each metal species binds strongly with the apo‐high density lipoproteins; however, marked differences exist in the effects produced upon high density lipoprotein structure by the inorganic ions and CH3HgCl.
Increase of gangliosides in atherosclerotic human aortas
Authors: Breckenridge W. C. , Halloran J. L. , Kovacs K. , Silver M. D. 
Published: November 2006

AbstractPreparations of human thoracic aortas containing intima and media were obtained post‐mortem, and gangliosides were isolated by standard techniques. The quantity of ganglioside sialic acid, as assayed by gas liquid chromatography, was lowest in normal aortas (33±9 nmoles N‐acetyl neuraminic acid/g wet tissue) and progressively increased in aortas containing predominantly fatty streaks (54±1 nmoles N‐acetyl neuraminic acid/g wet tissue), raised yellow plaques (88±23 nmoles N‐acetyl neuraminic acid/g wet tissue), and ulcerated lesions (270±44 nmoles N‐acetyl neuraminic acid/h wet tissues). Both thin layer chromatography of the gangliosides and gas liquid chromatography of the constituent sugars demonstrated the presence of a ganglioside with properties similar to a monosialyl lactosyl ceramide (GM3) as the major ganglioside. A ganglioside with similar chemical characteristics was isolated from plasma and low density lipoproteins.
X‐ray diffraction study of some normal alkyl esters of long‐chain acids
Authors: Lutz D. A. , Eddy C. R. , Hunter J. J. 
Published: November 2006

AbstractX‐ray powder diffraction data are reported for 15 normal long‐chain esters. The compounds represent all combinations of acid and alcohol where the acid portion is n‐tetradecanoic, n‐hexadecanoic, or n‐octadecanoic acid, and the alcohol portion is n‐tetradecanol, n‐pentadecanol, n‐hexadecanol, n‐heptadecanol, or n‐octadecanol. The individual compounds can be identified and distinguished by the diffraction data. Several of the esters have long spacings that are a linear function of the number of carbon atoms in the molecule and are consistent with a similar function for ethyl esters of long‐chain acids. The remainder of the compounds crystallize in other polymorphic forms and therefore do not follow this function.
Quantitative and qualitative lipid correlation in experimental endogenous hyperlipemia
Authors: Butkus Antanas , Berretoni J. N. 
Published: November 2006

AbstractThe reversible endogenous hyperlipemia in dogs, elicited by the detergent Triton which was given intravenously, was used to study the interrelations of serum lipids. In the cholesterol ester fraction an increase occurs in both monounsaturated and in saturated fatty acids, excepting myristic; while a decrease occurs in polyunsaturated fatty acids. The fatty acids of cholesterol esters of normal dogs contain 22% oleic acid, and only 24% when serum lipids are increased to almost double their normal value (TC=400–500 mg/100 ml). However there is a critical level above which a rapid rise in oleic acid occurs and, in severe hyperlipemia (TC=1500 ±430 mg/100 ml), this acid constitutes almost half of the esterified fatty acid component.Since there is no evidence that Triton directly regulates fatty acid synthesis, the lipid fraction‐fatty acid interrelationship may be secondary to lipid mobilization from endogenous sources. This concept is supported by the fact that the increased serum fatty acids are only those which can be synthesized by animals. It is suggested, on the basis of a marked increased of endogenously produced fatty acids, that, at critical lipid levels, shortage of polyunsaturated fatty acids from exogenous sources occurs. This might be of sufficient degree to accelerate fatty acid synthesis to meet the need for fatty acids for energy requirements. There may also be need of fatty acid for esterification of chiefly the accumulated free cholesterol split from lipoprotein by Triton.Triton‐induced changes in cholesterol ester fatty acids result in patterns which closely resemble those in the adipose tissue of dog and man and in the serum of human endogenous hyperlipemia.
Eicosenoic acid and other fatty acids ofSapindaceae seed oils
Authors: Hopkins C. Y. , Swingle R. 
Published: November 2006

AbstractThe seed oils of 11 species ofSapindaceae were examined, and their fatty acid composition was determined.cis‐11‐Eicosenoic acid was identified as the major fatty acid ofKoelreuteria paniculata. It was present in nine of the 11 species in amounts from 8–60% of the total fatty acids and is evidently a common component of oils of this plant family. Arachidic acid was present in amounts up to 11%. Only three of the oils had acids of chain length greater than C‐20. Seed oils of certain species ofKoelreuteria andCardiospermum are good potential sources of 11‐eicosenoic acid.
Fatty acid alterations during migration and early sea water growth of chum salmon (Oncorhynchus keta)
Authors: Saddler J. B. , Koski K. V. , Cardwell R. D. 
Published: November 2006

AbstractLipid and fatty acid characteristics were examined in chum salmon fry (Oncorhynchus keta) in freshwater, at various stages in their early growth in sea water, and 7 days after their artificial introduction from freshwater into sea water. The average lipid content of salmon fry in freshwater decreased from 2.5% in newly emerged fry (30–40 mm fork length) to 1.7% in older fry (40–50 mm). Lipid content did not appear to change during migration, but steadily declined during the first 4–6 weeks of sea water growth to 1.7%. Within 7 days after artificial introduction into sea water, lipid content of the salmon had declined to 1.4%. Extended residence in freshwater, e.g., 2–3 weeks, resulted in a fatty acid pattern more characteristic of freshwater fish, whereas residence in sea water resulted in patterns more characteristic of marine fish. Salmon artificially introduced into sea water incurred substantial diminutions in polyunsaturated fatty acids. This response did not occur in wild fry in the marine environment and may therefore be due to the stresses of capture, handling, anesthesia, partial starvation and confinement to which the artificially reared fish were exposed.
Effects of ethylp‐chlorophenoxyisobutyrate on biliary secretion of bile acids, cholesterol and phosphatidyl choline
Authors: Horning M. G. , Hebert R. M. , Roth R. J. , Davis D. L. , Horning E. C. , Fischer E. P. , Jordan G. L. 
Published: November 2006

AbstractThe effect of chronic administration of ethylp‐chlorophenoxyisobutyrate (CPIB) on the secretion of bile lipids was studied in four dogs with surgically implanted Thomas cannulae for periods of 2–7 months. The concentration of cholesterol, triglycerides andp‐chlorophenoxyisobutyric acid in serum and of bile acids, cholesterol and phospholipids (phosphatidyl cholines) in bile were measured. Chronic administration of CPIB resulted in a marked increase in the concentration of cholesterol, bile acids and phosphatidyl cholines in the bile of all dogs, and a decrease in serum cholesterol and triglyceride concentration in serum in three of the four dogs. Serum concentrations ofp‐chlorophenoxyisobutyric acid were monitored to insure the presence of the drug in the dogs; however, no correlation between serum levels ofp‐chlorophenoxyisobutyric acid and the concentration of biliary lipids was noted. The bile acids andp‐chlorophenoxyisobutyric acid were determined by gas chromatographic procedures and the structures were confirmed by gas chromatography‐mass spectrometry.
Lipid metabolism of brain tissue in culture
Authors: Menkes John H. 
Published: November 2006

AbstractTissue explants from frontal lobes of rat brain were used for the study of cerebral fatty acid metabolism. After tissues had been maintained in serum‐supplemented medium, a lipid free medium was substituted and metabolic studies were carried out. Under these conditions explants continued to take up lipid precursors for at least 48 hr. Stearic acid 1‐C14, palmitic acid 1‐C14 and lignoceric acid 1‐C14 were bound to cells as the free fatty acids or incorporafed into neutral lipids (particularly triglycerides), glycolipids and phospholipids. In the galactolipid fraction, cerebrosides were the principal radioactive lipids. Choline phosphoglycerides, ethanolamine phosphoglycerides, inositol phosphoglycerides and serine phosphoglycerides were the principal radioactive phospholipids. Fatty acids were incorporated into cellular lipids either unchanged or after desaturation, chain elongation, or both. In a patient with a demyelinating disease, precursor uptake was reduced and chain elongation and desaturation of the fatty acid was diminished. In a patient with generalized GM2 gangliosidosis, glycolipids other than cerebrosides were labeled to a greater extent than normal. These studies exemplify the usefulness of tissue explants for prolonged metabolic studies in normal and pathological specimens of brain.
Phospholipid metabolism in cells in culture
Authors: Rytter Darrel J. , Cornatzer W. E. 
Published: November 2006

AbstractThe proportions of the different lecithin fractions have been determined in HeLa and KB tissue culture cells and Ehrlich Ascites tumor. 82.8% of the total phosphatidyl choline phosphorus is found in fraction 3 of HeLa cells. The major phosphatidyl cholines found in KB cells and Ehrlich Ascites tumor are in fractions 3 and 4 and representing 66.6% and 88.7% of the total phosphatidyl choline P, respectively. The incorporation of 1,2‐14C‐choline and 1,2‐14C‐ethanolamine into the various phosphatidyl choline fractions has been assayed to determine their biosynthesis in Ehrlich Ascites tumor. The incorporation of 1,2‐14C‐choline into fractions 3 and 4 is 100 times the 1,2‐14C‐ethanolamine. This evidence indicates that the methylation pathway of phosphatidyl choline synthesis is very low in HeLa, KB and Ehrlich Ascites cells.
Cholesteryl ester metabolism in tissue culture cells: II. Source of accumulated esterified cholesterol in Fu5AH rat hepatoma cells
Authors: Rothblat G. H. , Arbogast L. , Kritchevsky D. , Naftulin M. 
Published: November 2006

AbstractPrevious investigations had demonstrated that Fu5AH rat hepatoma cells accumulated large quantities of esterified cholesterol when grown in hyperlipemic rabbit serum. The present investigation has determined the sources of the cellular esterified cholesterol when the cells were grown in hyperlipemic serum. Cellular esterification of endogenous and exogenous free cholesterol contributed 10% and 30%, respectively. The remaining 60% of the accumulated cellular esterified cholesterol was derived from exogenous (serum) cholesteryl esters. Evidence for the hydrolysis of a portion of the incorporated esterified cholesterol is presented. A stimulation of free cholesterol incorporation and cellular esterification is elicited by hyperlipemic serum and serum lipoproteins when compared to normolipemic serum present at equivalent exogenous cholesterol concentrations. The effect of hyperlipemic serum is reduced by Tween‐80 and Triton WR‐1339. Comparative data on esterified cholesterol accumulation, free cholesterol incorporation, and cellular cholesterol esterification in Fu5‐5 rat hepatoma cells, L‐cells, and rabbit aortic medial cells are presented.
Preparation and purification of lipid hydroperoxides from arachidonic and γ‐linolenic acids
Authors: Funk Max O. , Isaac Ramdas , Porter Ned A. 
Published: November 2006

AbstractCommercial soybean lipoxygenase may be used under carefully controlled reaction conditions to give high yields of lipid hydroperoxides. Lipid hydroperoxides so derived from γ‐linolenic or arachidonic acid may be purified by high pressure liquid chromatography. Thus, commercial lipoxygenase serves as a viable source for 100 mg quantities of lipid hydroperoxides.