bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of androgens on serum lipids and lipoproteins
Authors: Solyom Antal 
Published: November 2006

AbstractThe effects of androgens on lipid transport and metabolism have been reviewed. These effects are probably independent of the androgenic and anabolic activities of the androgens, although the molecular mechanism of action is still not known. Presumably the lowering by androgens of the concentrations of serum lipids and lipoproteins could be the consequence possibly of a primary, inhibitory effect on the synthesis of apolipoprotein A. In addition the role of increased lipolytic activities in plasma and of effects on intermediatry metabolism has been considered.
24‐Methylenecholesterol: Isolation and identification as an intermediate in the conversion of campesterol to cholesterol in the tobacco hornworm
Authors: Svoboda J. A. , Thompson M. J. , Robbins W. E. 
Published: November 2006

Abstract24‐Methylenecholesterol was positively identified as an intermediate in the dealkylation and the conversion of campesterol to cholesterol in the tobacco hornworm,Manduca sexta (L.). Biochemical and nutritional studies with3H‐labeled campesterol and 24‐methyl‐enecholesterol indicated that the conversion of campesterol to cholesterol in this insect includes the following metabolic sequence: campesterol, 24‐methylene‐cholesterol, desmosterol, cholesterol.
Serum lipoproteins: A paper electrophoresis method without albumin in the buffer
Authors: Moinuddin Mohammed , Taylor Linnard 
Published: November 2006

AbstractA paper electrophoresis method is described in which four serum lipoprotein components are separated without the use of albumin in the buffer. Tris‐EDTA‐boric acid buffer, Oil Red O staining solution prepared in 52.8% instead of the usual 60% alcohol, and solvent‐extracted paper strips are the distinguishing features of this procedure. The system was effective not only in separating chylomicron, β‐ and α‐lipoproteins into well‐defined bands, but also in separating very low density or pre‐β‐lipoprotein distinctly in some samples and partially in others. The advantages of this procedure are low background staining and, in comparison to the procedure using albumin in the buffer, a sharper alpha band. This sharpened α‐band gives a sharper peak in densitometric scanning. Electrophoresis could be performed for 16 hr or 4 hr. The 4‐hr electrophoresis run produced electrophoregrams with even denser and sharper bands than the 16‐hr run.
Isoenzymes of lipoxidase
Authors: Hale Sara A. , Richardson T. , Von Elbe J. H. , Hagedorn D. J. 
Published: November 2006

AbstractA polyacrylamide disc gel electrophoretic technique is described for studying isoenzymes or multiple molecular forms of lipoxidase in extracts of fresh green peas, pea seeds, wheat, fresh green beans and green bean seeds. After electrophoresis, gels containing starch were incubated with linoleic acid. Hydroperoxide bands were visualized by treating the gel with acidic potassium iodide. Staining specificity was established using the following criteria. Activity was absent when extracts or gels were boiled and when linoelaidic and oleic acids were used as substrates. Cyanide did not inhibit staining, whereas α‐tocopherol, hydroquinone and nordihydroguaiaretic acid did. Prevention of the appearance of artifactual bands was attempted by: pre‐electrophoresis of the gels; electrophoresis in the presence of thioglycollic acid; elimination of the large pore gel; pH adjustment of the plant extracts; and extraction of extract solids with lipid solvents. Gel patterns indicated two to three lipoxidase bands for fresh green peas and pea seeds, one to two bands for fresh green beans and green bean seeds, and four bands for wheat.
Effect of dietary cholesterol on bile‐acid composition of gall bladder bile from guinea pigs
Authors: Tung Jwu‐Sheng , Ostwald Rosemarie 
Published: November 2006

AbstractThe composition of gall bladder bile acids from control and cholesterol‐fed, anemic guinea pigs was analyzed by thinlayer‐chromatographic and colorimetric techniques. In both control and cholesterol‐fed animals, the gall bladder bile acids constituted about one third of the total bile solids. The main component of the bile acids of both groups of animals was chenodexycholic acid, which was predominantly conjugated with glycine. No cholic acid was present although this is the main bile acid in most mammals. The major difference in bile composition between control and cholesterol‐fed animals was the conjugation pattern of chenodeoxycholic acid. The ratio of glycochenodeoxycholic to taurochenode‐oxycholic acid was high, 6.4, for control animals, and decreased to 2.4 for the cholesterol‐fed, anemic animals. Impaired liver function, limited availability of glycine, and greater efficiency of taurocholanic acids for the disposal of excess cholesterol may be involved in the mechanism for this phenomenon.
Addition ofN‐acetylcysteine to linoleic acid hydroperoxide
Authors: Gardner H. W. , Weisleder D. , Kleiman R. 
Published: November 2006

AbstractCatalyzed by 10−5 M ionic iron in 80% ethanol,N‐acetylcysteine added to linoleic acid hydroperoxide, forming a thiobond. Reaction of a specific isomer of the hydroperoxide, 13‐hydroperoxy‐trans‐11,cis‐9‐octadecadienoic acid, andN‐acetylcysteine, forms a number of products, of which two were identified as addition compounds. One addition product was 9‐S‐(N‐acetylcysteine)‐13‐hydroxy‐10‐ethoxy‐trans‐11‐octadecenoic acid, and the other was 9‐S‐(N‐acetylcysteine)‐10,13‐dihydroxy‐trans‐11‐octadecenoic acid.
Effect of the nature and amount of dietary energy on lipid composition of rat bone marrow
Authors: Das S. K. , Scott M. T. , Adhikary P. K. 
Published: November 2006

AbstractThe effect of the nature and amount of dietary calories on the lipid composition of bone marrow of rats was studied. Male weanling rats were fed 3 isocaloric diets, containing high carbohydrate, normal protein, and high protein, and a fourth high fat diet for 49 days. Feeding of the high carbohydrate, high protein, and high fat diets caused a significant increase in the level of total lipids compared to the normal protein diet. This increase of total lipids was due primarily to the increase in the level of triglycerides. There was no significant difference in fatty acid composition of either nonpolar or polar lipids of bone marrow among rats fed high carbohydrate diet and those fed normal protein diet. A comparison of fatty acid compositions between bone marrow lipids of rats fed high protein diet and the other 2 isocaloric diets revealed that the proportion of palmitic acid was higher and the proportion of oleic acid was lower in animals fed high protein diet than in animals fed the other 2 diets. Compared to the 3 isocaloric low fat diets, dietary feeding of high fat diet caused a decrease in the proportion of palmitic and palmitoleic acids and an increase in the proportion of oleic and linoleic acids in total fatty acids of both nonpolar and polar lipids.
Fluorescent products and polyunsaturated fatty acids of human testes
Authors: Trombly R. , Tappel A. L. , Coniglio J. G. , Grogan W. M. , Rhamy R. K. 
Published: November 2006

AbstractLipid soluble fluorescent pigments from human testis were fractionated by silicic acid column chromatography and silica gel thin layer chromatography. Fluorescence analyses revealed a family of at least 3 compounds with similar fluorescence properties, including excitation and emission maxima, reversible fluorescence quenching by alkaline pH, and fluorescence quenching by heavy metal chelation. These fluorescence characteristics strongly indicated the presence of the conjugated Schiff base fluorophore −N=C−C=C−N−. The chromatographic separations employed enabled a more definitive fluorescence characterization of the lipid soluble pigments known to accumulate in tissues with age and as a result of lipid peroxidation. Total lipids and fatty acid composition of the total lipids were determined. Polyenoic acids constituted about 40% of the total fatty acids. Histological examination of the tissues revealed some degeneration and edema, but significant spermatogenesis and normal complement of Leydig cells.
Biosynthesis of fatty acids from acetate in soybean suspension cultures
Authors: Stearns E. M. , Morton W. T. 
Published: November 2006

AbstractSuspension cultures of finely divided soybean cells established from callus were incubated with sodium [1‐14C] acetate for periods up to 86 hr. Lipids and fatty acids were analyzed for radioactivity in samples harvested at logarithmic time periods. Incorporation of acetate into cell lipid was directly proportional to the logarithm of time up to 32 hr, after an initial lag of 4–6 hr. Most of the lipid radioactivity was found in the phospholipid fraction, and all common soybean fatty acids became labeled within 6 hr. The order of labeling and distribution of radioactivity with time were essentially the same as in tissues from intact growing plants. These results support the concept of sequential desaturation of oleic acid in the cells. It was concluded that valid studies of the biosynthesis of common lipids in the soybean can be carried out for extended periods of time by use of undifferentiated cells in suspension cultures.
Inhibitive effects of structurally modified azasteroids and related nitrogen containing steroids on insect growth and development
Authors: Thompson M. J. , Serban N. N. , Robbins W. E. , Svoboda J. A. , Shortino T. J. , Dutky S. R. , Cohen C. F. 
Published: November 2006

AbstractA number of azasteroids and other nitrogen containing steroids with a modified nucleus or side chain were prepared and tested for their inhibitory effects on the growth and development of several species of insects. Structure‐activity studies showed that compounds with a structurally related steroid nucleus and side chain were approximately equal in inhibitory activity for a particular species. The replacement of the tertiary amino group in the side chain of the 5β‐steroid with other nitrogen substituents, such as nitro, cyano, acetylamino, or a quaternary ammonium salt, resulted in a considerable loss of inhibitive activity in the tobacco hornworm or the yellowfever mosquito. However, certain modifications of the azasteroid nucleus resulted in compounds that still retained high biological activity. As a result, a compound was synthesized that lacked the A and B rings of the steroid nucleus and that inhibited insect growth, molting, and metamorphosis and the Δ24‐sterol reductase enzyme system of the tobacco hornworm.
Lipogenesis by intact hepatocytes from normal and diabetic rats
Authors: Raghupathy E. , Orthlieb C. , Abraham S. 
Published: November 2006

AbstractIntact hepatocytes isolated from livers of diabetic rats demonstrate the characteristic decreased lipogenic capacities as compared to normal. Administration of insulin to diabetic rats restores these capacities to near normal levels. The results emphasize the potential that the hepatocyte system has for the study of hormonal regulation of lipogenesis.
Lipoxygenase isozymes of peanut
Authors: Sanders T. H. , Pattee H. E. , Singleton J. A. 
Published: November 2006

AbstractLipoxygenase was isolated and partially purified from peanut seed by ammonium sulfate precipitation, gel filtration, and ion exchange column chromatography. Three isozymes of lipoxygenase were identified. Two had pH optima of 6.2, and the other an optimum of 8.3. Molecular weight of each isozyme was 7.3×104, as determined by gel filtration. The alkaline optimum isozyme was not inhibited by NaCN and was inhibited by CaCl2 except at very low concentrations. The acid optimum isozymes were inhibited by NaCN and were stimulated by CaCl2 concentrations up to ca. 0.7 mM.
Double bond location in polyenoic fatty esters through partial oxymercuration
Authors: Plattner R. D. , Spencer G. F. , Kleiman R. 
Published: November 2006

AbstractA rapid micro‐procedure has been developed to locate double bonds in fatty acid methyl esters containing from one to four double bonds. Reaction of the ester with an equal molar amount of mercuric acetate in methanol and reduction with sodium borohydride, followed by hydrogenation, produce a mixture of monomethoxy alkanoates. The mass spectrum of this mixture is simpler and more definitive than that from the completely methoxylated polyenoate. Only one methoxyl group is present per molecule, and the mass spectrum of the mixture is indicative of all olefinic positions. Four intense ions are observed for all double bonds examined, except Δ3, where the double bond is represented, by only two ions. Hydrogenation in a gas chromatograph reduces total analysis time to 1 hr.
Biosynthesis of prostaglandin E1 by human seminal vesicles
Authors: Hamberg Mats 
Published: November 2006

Abstract[1‐14C] 8,11,14‐Eicosatrienoic acid was converted into prostaglandin E1 when incubated with a homogenate of human seminal vesicles. No conversion could be detected with homogenates of human prostate or testis.
Hypolipidemic activity of (−)‐hydroxycitrate
Authors: Sullivan Ann C. , Triscari Joseph , Hamilton James G. , Ontko Joseph A. 
Published: November 2006

AbstractThe influence of (−)‐hydroxycitrate, a potent competitive inhibitor of adenosine triphosphate (ATP) citrate lyase, on serum triglyceride and cholesterol levels, and in vitro and in vivo rates of hepatic fatty acid and cholesterol synthesis was investigated in normal and hyperlipidemic rat model systems. (−)‐Hydroxycitrate reduced equivalently the biosynthesis of triglycerides, phospholipids, cholesterol, diglycerides, cholesteryl esters, and free fatty acids in isolated liver cells. In vivo hepatic rates of fatty acid and cholesterol synthesis determined in meal‐fed normolipidemic rats were suppressed significantly by the oral administration of (−)‐hydroxycitrate for 6 hr, when control animals exhibited maximal rates of lipid synthesis; serum triglyceride and cholesterol levels were significantly reduced by (−)‐hydroxycitrate. In two hypertryglyceridemic models—the genetically obese Zucker rat and the fructose‐treated rat—elevated triglyceride levels were due, in part, to enhanced hepatic rates of fatty acid synthesis. (−)‐Hydroxycitrate significantly reduced the hypertriglyceridemia and hyperlipogenesis in both models. The marked hypertriglyceridemia exhibited by the triton‐treated rat was only minimally due to increased hepatic lipogenesis; (−)‐hydroxycitrate significantly inhibited both serum triglyceride levels and lipogenesis in this model.
An intervention study—The aspirin myocardial infarction study
Authors:   The Aspirin Myocardial Infarction Research Group
Published: November 2006

AbstractThe Aspirin Myocardial Infarction Study is a randomized, double‐blind clinical trial designed to study the potential value of aspirin in the reduction of mortality in patients who have had a prior myocardial infarction. This trial is based upon several previously published studies which suggest that aspirin may be valuable in prevention of coronary thrombosis. The requirement of 4200 patients dictates that the study must be multicenter, and good design requires that the study be collaborative with central monitoring and an elaborate committee structure to insure uniformity and comparability.
Comparative effect of glucagon, dibutyryl cyclic AMP, and epinephrine on the desaturation and elongation of linoleic acid by rat liver microsomes
Authors: de Gómez Dumm Irma N. T. , de Alaniz María J. T. , Brenner Rofolfo R. 
Published: November 2006

AbstractThe effect of glucagon, dibutyryl cyclic adenosine 3′,5′‐monophosphate, and epinephrine on the biosynthesis of polyunsaturated fatty acids of the linoleic acid family was studied. The incubations were performed with rat liver microsomes and labeled linoleic acid under desaturating and elongating conditions. Under desaturating conditions, linoleic acid was converted to γ‐linolenic acid, whereas under elongating conditions it was converted to 20∶2ω6. Glucagon, dibutyryl cyclic AMP, and epinephrine decreased the oxidative desaturation of linoleic acid to γ‐linolenic acid while the elongating reaction was not modified in the experimental conditions tested. Consequently, the results support the hypothesis that the oxidative desaturation of linoleic acid to γ‐linolenic acid is the main controllable step in the biosynthesis of polyunsaturated fatty acids of the linoleic acid family in the microsomes.
Lipid composition of 30 species of yeast
Authors: Kaneko Hiroshi , Hosohara Masako , Tanaka Masamichi , Itoh Toshihiro 
Published: November 2006

AbstractThe detailed composition of cellular lipid of more than 23 species of yeast has been determined quantitatively by thinchrography on quartz rods, a method previously used for estimating cellular lipids of seven species of yeast. That data was fortified by neutral and phospholipid quantitations on 30 species of yeast cells. Most of the test organisms contained 7–15% total lipid and 3–6% total phospholipid per dry cell weight, except for the extremely high accumulation of triglycerides in two species ofLipomyces. Qualitatively, 30 species of yeast cells contained similar neutral lipid constituents (triglyceride, sterol ester, free fatty acid, and free sterol) and polar lipid components (phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine, phosphatidyl inositol, cardiolipin, and ceramide monohexoside) without minor constituents. Based on the quantitative composition of neutral lipids, the 30 species of yeast were divided into two groups, the triglyceride predominant group and the sterol derivative group. These groupings were fairly well overlapped from the standpoint of the distribution characteristics of fatty acid. The relative polar lipid compositions also grossly resembled each other. Only one exception of polar lipid composition in yeast cells was found inRhodotorula rubra species which contained phosphatidyl ethanolamine as the most abundant phospholipid. Fatty acid distribution patterns in yeast cells consistently coincided with other reports concerning fatty acid composition of yeast cells. Correlation of lipid composition and classification of yeasts are suggested and discussed.
Fatty acids ofLindera umbellata and other Lauraceae seed oils
Authors: Hopkins C. Y. , Chisholm Mary J. , Prince Linda 
Published: November 2006

AbstractSeed kernel oils of seven species of Lauraceae were examined and the fatty acid composition of six of these was determined. The oil ofLindera umbellata had 4% ofcis‐4‐decenoic, 47% ofcis‐4‐dodecenoic, and 5% ofcis‐4‐tetradecenoic acid in the total fatty acids. Positive identification of these acids was made and new derivatives were prepared. Possible routes of biosynthesis are discussed.Oils from the other species did not contain more than a trace of unsaturated C10−C14 acids. Their major acids were capric and lauric with varying amounts of unsaturated C18 acids.
Quantitative determination of unsaturation in oils by using an automatic‐titrating hydrogenator
Authors: Miwa T. K. , Kwolek W. F. , Wolff I. A. 
Published: November 2006

AbstractA procedure was developed to adapt an automatic‐titrating hydrogenator to the rapid determination of unsaturated carbon‐carbon bonds in seed oils. Its utility as a research tool for detecting unusual types of unsaturation was demonstrated by analysis of 35 oils. When the hydrogen‐iodine value of an oil determined by the hydrogenator differed significantly from the iodine value by the Wijs method, the presence of unsaturation such as acetylenic or conjugated double bonds was indicated. For repetitive analysis of samples of the same oil, or of oils having nearly the same extent of unsaturation, the hydrogenator can successfully accomodate injection of a new sample every 2 to 5 min. Possible utility of the method for monitoring samples from a processing plant is apparent.
Studies on the enzymatic synthesis of cholesterol: Use of a liver acetone powder
Authors: Scallen Terence J. , Schuster M. W. , Dhar A. K. , Skrdlant H. B. 
Published: November 2006

AbstractWe have defined special conditions for the preparation of an acetone powder of rat liver microsomes which is capable of converting squalene to cholesterol in high yield. This preparation is also useful for the demonstration of cofactor requirements for certain reactions in sterol biosynthesis. Buffer washed acetone powders are virtually completely dependent upon the 105,000 ×g supernatant of rat liver (S105) for activity, yet S105 by itself is inert in sterol synthesis. The ability of S105 to stimulate sterol synthesis is heat liable, nondialyzable, trypsin sensitive, and has been partially purified by ammonium sulfate precipitation and chromatography on Sephadex G‐200. These results plus other experiments support the following hypothesis: the 105,000 ×g supernatant of rat liver (S105) contains a noncatalytic carrier protein (Sterol Carrier Protein or SCP) which originates from the endoplasmic reticulum, binds the substrate, and makes the substrate reactive to the sterol synthesizing enzymes present in the acetone powder of liver microsomes. The participation of SCP may be an important general mechanism in the biological synthesis of cholesterol.
Metabolism of lathosterol byDrosophila pachea
Authors: Goodnight Kenneth C. , Kircher Henry W. 
Published: November 2006

AbstractDrosophila pachea is a Sonoran Desert cactiphilic species unable to utilize cholesterol or cholestanol for larval growth and maturation. Lathosterol (7‐cholesten‐3β‐ol) was added to a sterol deficient medium on which an axenic culture ofD. pachea was maintained. 7‐Dehydrocholesterol was identified as the sterol metabolite in adult flies by gas liquid and thin layer chromatography and by its UV spectrum.
Inhibition of acid esterase in rat liver by 4,4′‐diethylaminoethoxyhexestrol
Authors: Kasama Kazuo , Yoshida Katsumi , Takeda Susumu , Tsujimura Ryotaro , Hasegawa Shinichi 
Published: November 2006

AbstractThe effect of 4,4′‐diethylaminoethoxyhexestrol (DH) on acid esterase in rat liver was studied in vivo and in vitro. The acid esterase activity in the livers of rats treated with 0.125% DH for 1 week was found to decrease more than 60% as compared with that in untreated rats. The addition of DH to the incubation medium caused considerable inhibition of the acid esterase activity in lysosome from untreated rat liver, and the inhibition type appears to be noncompetitive. The acid lipase activity in rat liver lysosome was also inhibited by DH. Some antihistamic agents and chloroquine also inhibited the acid esterase activity in rat liver lysosome.
Modulation by ketone bodies of the rate of fatty acid synthesis in mammary gland slices from lactating rats
Authors: Bartley J. C. 
Published: November 2006

AbstractThe absolute rate of fatty acid synthesis was measured in slices of mammary gland from lactating rats by incubation in [3H]2O‐labeled medium containing 10 mM D‐3‐hydroxybutyrate or aceto‐acetate alone and paired in combination with 10 mM glucose, lactate, or pyruvate. When compared with our previous studies, the ketone bodies alone supported significant fatty acid synthesis; the rate of synthesis from either ketone body and lactate was higher than that from pyruvate and lactate, and that from pyruvate and glucose; the rate of synthesis from D‐3‐hydroxybutyrate and lactate was the highest we have observed in the absence of an exogenous substrate for the hexose monophosphate pathway. This study confirms our previous contention that, in rat mammary gland, substrates formed in the mitochondria can be utilized in the cytosol to provide some of the NADPH necessary for fatty acid synthesis.