bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metazoan lipids: An unusual association of saturated sterols with relatively saturated fatty acids in the cilia ofCiona intestinalis
Authors: Morris Robert J. , Bone Q. 
Published: December 2006

AbstractCilia from the tunicateCiona intestinalis have been analyzed for, their biochemical compositions. Cholestanol is found to be a major steroidal component, whereas the phospholipids are composed mainly of C14−C18 saturated fatty acids. The saturated nature of the lipids may be related to specific requirements of the ciliary membrane.
Fatty acids in plasma and red cell membranes in normal humans
Authors: Manku M. S. , Horrobin D. F. , Huang Y‐S. , Morse N. 
Published: December 2006

AbstractA detailed study was made of the fatty acid composition of plasma triglycerides, free fatty acids, phospholipids, red cell total phospholipids, phosphatidylcholine and phosphatidylethanolamine in 32 normal males and 18 normal females. No sex differences could be detected. There were substantial differences in the compositions of the various fractions and long‐chain polyunsaturated fatty acids were particularly important in the red cells.
Oxidation of lipids: III. Oxidation of methyl linoleate in solution
Authors: Yamamoto Yorihiro , Niki Etsuo , Kamiya Yoshio 
Published: December 2006

AbstractThe effects of oxygen pressure, substrate concentration and solvent on the rate and products of oxidation of methyl linoleate were studied at 50 C with azobisisobutyronitrile as a radical initiator. The absolute and quantitative numbers for oxygen uptake, substrate disappearance, and formation of conjugated diene and hydroperoxides were measured. Under the present conditions, 4 conjugated diene hydroperoxides, 13‐hydroperoxy‐9‐cis, 11‐trans‐(2a), 13‐hydroperoxy‐9‐trans, 11‐trans‐(3a), 9‐hydroperoxy‐10‐trans, 12‐cis‐(4a), and 9‐hydroperoxy‐10‐trans, 12‐trans‐(5a) octadecadienoic acid methyl esters, were formed almost quantitatively. The rate of oxidation decreased with decreasing oxygen pressure. However, the ratio ofcis,trans totrans,trans hydroperoxides, (2a+4a)/(3a+5a), was independent of oxygen pressure, and this ratio increased with increasing methyl linoleate concentration, as found recently by Porter. Further, the rate of oxidation and the ratio ofcis,trans/trans,trans hydroperoxides were dependent on solvent and increased with an increase in dielectric constant of solvent. A mechanism of methyl linoleate oxidation consistent with these results is discussed.
Modulation of tissue prostaglandin synthesizing capacity by increased ratios of dietary alpha‐linolenic acid to linoleic acid,
Authors: Marshall Lisa A. , Johnston Patricia V. 
Published: December 2006

AbstractSemipurified diets containing ratios of α‐linolenic acid (18∶3ω3) to linoleic acid (18∶2ω6) of 1/32, 1/7, 1/1, and 3.5/1 in the form of corn oil, soybean oil, soybean/linseed oil mix and linseed oil were fed to rats for 2 months. The first 3 diets were fed to another group of rats for 4 months and to a group through the second generation. Fatty acid analysis of liver and spleen ethanolamine glycerophosphatide revealed that, as the level of 18∶3ω3 in the diet increased, the elongated, desaturated metabolites of the ω6 series decreased and the ω3 series increased. Noteworthy was the depression in the amount of the precursor of the 2‐series prostaglandins (PG) as the ω3 levels increased. Synthesis of PG by liver of rats fed 2 or 4 months markedly decreased, but at 2 months in thymus and spleen, it showed a trend toward decreasing only. Brain slices showed no decrease in PGF2α synthesis after 4 months, but did decrease significantly after feeding the diets to the second generation. Synthesis of PGE2 by spleen homogenate from the second generation also significantly decreased. The replacement of ω6 series fatty acids by ω3 series is explained by the effective competition of 18∶3ω3 over 18∶2ω6 for the Δ6 desaturase. Depressions in PG synthesis by high dietary 18∶3ω3 is explained by the competitive inhibition of the PG synthetase complex by 20∶5ω3 as well as by the decreased levels of 20∶4ω6.
The effect of dietary lipid on the lipoprotein status of the mongolian gerbil
Authors: Leach Andrea B. , Holub Bruce J. 
Published: December 2006

AbstractThe Mongolian gerbil,Meriones unguiculatus, may be a suitable animal model for the investigation of dietary lipid effects on cholesterol metabolism. The effects of dietary cholesterol, and its possible interaction with the type of dietary fat, on the lipoprotein status of this animal have not been examined previously. In the present research, the effects of adding 0.5% cholesterol to diets high in saturated (19.5% beef tallow: 0.5% safflower oil) or polyunsaturated (20% safflower oil) fats on the lipoprotein status of the gerbil were determined after 11 and 22 days of feeding. Lipoproteins (VLDL, LDL and HDL) were separated by sequential ultracentrifugation. Their cholesterol, phospholipid and protein concentrations were determined colorimetrically. In the absence of 0.5% cholesterol, safflower oil lowered the concentration (mg/100 ml) of cholesterol in each of the VLDL, LDL and HDL relative to beef tallow (BT) without greatly influencing the cholesterol distribution amongst them. The HDL carried the majority of the serum cholesterol and the VLDL transported the smallest amount. However, inclusion of 0.5% dietary cholesterol resulted in a redistribution of cholesterol amongst the lipoproteins so that the VLDL and LDL became the major and the HDL the minor carriers. Dietary cholesterol also brought about a rise in the VLDL and LDL concentrations (mg/100 ml) of cholesterol, phospholipid and protein and altered the VLDL and LDL compositions. No such changes were observed in the HDL, indicating that the HDL are relatively resistant to any of the possible effects of cholesterol feeding measured in this experiment. The specific mechanisms responsible for the changes observed in the lipoprotein status of the gerbil remain to be elucidated.
Lung surfactant and fatty acid composition of lung tissue and lavage of rats fed diets containing different lipids
Authors: Alam Syed Q. , Alam Bassima S. 
Published: December 2006

AbstractTwo nutritional models, essential fatty acid (EFA) deficiency and the feeding of saturated vs unsaturated fats, were used to determine the effects of dietary lipids on the fatty acid composition of rat lung and lavage. Semipurified diets containing 7% corn oil, 7% hydrogenated coconut oil (EFA‐deficient), 10% butter or 10% safflower oil were fed to dams during lactation and thereafter to their offspring for a total of 24 weeks. Lipids were extracted from the lung lavage and lung tissue and their fatty acid composition was determined. The content of dipalmitoylphosphatidylcholine (DPPC), the main surfactant in the lungs, was also determined. The results show that the levels of DPPC in the lungs of rats fed 10% butter decreased although the decrease in the EFA‐deficient rats was greater. Comparing rats fed butter with those fed corn oil, there were also modifications in the fatty acid composition of the total lipids and phospholipids of lung tissue and lavage as well as in phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol +phosphatidylserine fractions isolated from the lung tissue. The changes in fatty acid composition were somewhat fewer in rats fed butter then in those fed an EFA‐deficient diet. The results suggest that a marginal EFA deficiency produced in rats by long‐term feeding of 10% butter may account for the reduction in DPPC levels and in the changes in fatty acid composition in the lung tissue and lavage.
Complete assignment of the carbon‐13 NMR spectrum of oiticica oil: Interpretation of chemical shifts in conjugated systems
Authors: Bergter L. , Seidl P. R. 
Published: December 2006

AbstractAll absorptions on the carbon‐13 spectrum of α‐ and β‐eleostearic and licanic acid esters are assigned. A combination of off‐resonance decoupling and lanthanide‐induced shifts coupled to polarization by a remote keto group was necessary to establish the correct order of conjugated olefinic carbon atoms. By themselves, none of these techniques would have sufficed to reach the cortect conclusions. Steric effects are accounted for but may lead to wrong results if proper consideration is not given to other factors.
High field13C nuclear magnetic resonance spectrum of the olefinic carbons of the triglycerides of palm oil
Authors: Ng Soon 
Published: December 2006

AbstractIn the triglycerides of palm oil (or any vegetable oil or fat), an unsaturated fatty acid (oleic or linoleic) attached to the 2‐glycerol carbon can be distinguished from one attached to the 1‐ or 3‐glycerol carbon by high (or medium) field13C nuclear magnetic resonance (NMR) analysis of the olefinic carbons. The chemical shift difference of the olefinic carbons in the fatty acid chain is characteristic of the chain's glycerol position and can therefore be used to identify the glycerol position of an unsaturated fatty acid in the triglyceride.
Phospholipid studies of marine organisms: V1 new α‐methoxy acids fromHigginsia tethyoides
Authors: Ayanoglu Eser , Popov Simeon , Kornprobst J. M. , Aboud‐Bichara Amira , Djerassi Carl 
Published: December 2006

AbstractThe phospholipids of the demospongeHigginsia tethyoides are shown to have at least 16 long‐chain α‐methoxy acids, which represent a new class of fatty acids. Among them are the saturated α‐methoxy acids containing 19–24 carbon atoms. The monounsaturated compounds are 2‐OMe‐Δ17‐24:1, 2‐OMe‐Δ18‐25:1, 2‐OMeΔ19‐26:1 and 2‐OMe‐Δ21‐28:1. The major diunsatured ones were shown to be 2‐OMe‐Δ5, 19‐26:2 and 2‐OMe‐Δ7, 21‐28:2. Small amounts of 2‐OMe‐23∶1, 2‐OMe‐26∶3; 2‐OMe‐27∶1 and 2‐OMe‐28∶3 were also encountered. Structures of the minor monounsaturated compounds were tentatively assigned as 2‐methoxy‐16‐tricosenoic acid and 2‐methoxy‐20‐heptacosenoic acids. The double bonds of the fatty acids show all‐cis configuration. Circular dichroism measurements indicate an R‐configuration for the α‐methoxy acids. The major component of the total phospholipid acid mixture is 5,9,23‐triacontatrienoic acid. Possible biosynthetic routes to these unusual phospholipid acids are discussed. The major phospholipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine. The distribution of fatty acids among the phospholipids was also investigated.
Lipolysis of corn, peanut and randomized peanut oils
Authors: Kim Hong K. , Kritchevsky David 
Published: December 2006

AbstractCorn oil, peanut oil and randomized peanut oil exhibit different atherogenic potentials; peanut oil being more atherogenic than the other oils. This study was conducted to ascertain if the atherogenicity of these oils was related to their rates of lipolysis. Using both pancreatic lipase and milk lipoprotein lipase (LPL), it was shown that the rated of lipolysis were corn oil>peanut oil>randomized peanut oil. The rates of lipolysis are not related to atherogenicity and may be affected by the distribution of long‐chain saturated fatty acids in the component triglycerides.
Plasma lipid and lipoprotein concentrations in an Egyptian male sample
Authors: Shoukry Malak I. , Fareed Samia 
Published: December 2006

AbstractThe distributions of plasma total cholesterol and triglyceride levels as well as plasma lipoprotein abnormalities were studied in 50 Egyptian males aged 20–69 years. Total cholesterol increased gradually with advancing age up to the seventh decade. In contrast, triglycerides peaked in the fifth decade, then declined. Type IV lipoprotein pattern was the most common abnormality (12%). Type II was less common (2.0%). Types I, III and V were not encountered. The mean plasma triglyceride and cholesterol levels were not markedly different from similar studies done on non‐Arab populations. The high incidence of hyperlipidemia among this group is worth noting, especially in the search for the coronary‐prone, since all of the type IV group had normal total cholesterol levels.
The effect of dihydroergotoxine on lipid peroxidation in vitro
Authors: Koréh Kinga , Seligman Myron L. , Demopoulos Harry B. 
Published: December 2006

AbstractDihydroergotoxine mesylate (DHET), an ergot alkaloid derivative, is widely used to treat senile cerebral vascular insufficiency. Aspects of this age‐related phenomenon may be due to deterioration by lipid oxidation of cellular membranes. DHET stabilizes EEG alpha frequencies, increases cerebral blood flow and oxygen uptake and accumulates in lipid‐rich structures of the brain. The effect of DHET was studied on iron‐catalyzed peroxidation of liposomes as measured by the thiobarbituric acid assay. It was found that DHET inhibits peroxidation in vitro in a dose‐dependent manner. These results suggest that DHET acts in part as a lipid antioxidant when used to treat senile cerebral vascular insufficiency.
A prostaglandin‐like fatty acid from a species in the cyperaceae
Authors: Van Aller Robert T. , Clark Leonard R. , Pessoney George F. , Van Rogers A. 
Published: December 2006

AbstractA C20 cyclic trihydroxy unsaturated fatty acid was isolated and characterized as a representative member of a group of oxygenated fatty acids from the aquatic sedge,Eleocharis microcarpa, Torr. Characterization of the compound as 11‐hydroxy‐14‐(3,5‐dihydroxy‐2‐methylcyclopentyl)‐tetradec‐9‐ene‐12‐yneoic acid was accomplished by various chemical and spectral methods.
Detection and determination of lipase (acylglycerol hydrolase) activity from various sources
Authors: Jensen Robert G. 
Published: December 2006

AbstractMethods for the detection and determination of lipases (acylglycerol hydrolases) and preparation of assays are reviewed including substrates, conditions and screening. Some newer methods for the determination of lipase activity are discussed. Several of these are: (a) titrimetry, (b) colorimetry of Cu soaps of free fatty acids (FFA), (c) colorimetry of chromophores in the acyl chain of FFA or in glycerol, (d) radioassay, (e) gas liquid chromatography, (f) enzymatic treatment of FFA and measurment of the resulting products, and (g) direct immunological determination of the lipase. Examples and sensitivities are given and advantages and disadvantages are described.
Fatty acid composition of liver lipids in rats fed brominated fatty acids
Authors: Wilson Glenn R. , Tinsley Ian J. , Lowry Robert R. 
Published: December 2006

AbstractFeeding rats diets containing brominated corn oil or di‐ or tetrabromostearate as the monoglyceride produced changes in fatty acid composition of liver lipids. Those changes associated with the feeding of brominated corn oil or tetrabromosterates could be explained by the accumulation of triglyceride, and the changes associated with the feeding of dibromostearate could result from the proliferation of a membrane system. A unique response to the feeding of diets containing brominated corn oil is an increase in the level of γ‐linolenic acid.
Effect of methylmercuric chloride on gangliosides of mouse neuroblastoma cells in culture
Authors: Rebel G. , Guerin P. , Prasad K. N. 
Published: December 2006

AbstractThe effect of methylmercuric chloride (CH3 HgCl) on the levels of gangliosides in mouse neuroblastoma cells (NBP2) in culture was studied. The treatment of NB cells with low concentrations (0.1 μM and 0.2 μM) of CH3 HgCl, which did not affect the growth rate or morphology, caused an increase in the level of the GM3 ganglioside without changing the level of other gangliosides. The treatment of NB cells with higher concentrations (0.5 μM and 1 μM) of CH3 HgCl, which inhibited the growth of NB cells, caused a decrease in the level of GM3 and an increase in the level of GM2. These results show that alterations in the levels of specific gangliosides can be observed in cells which do not exhibit any detectable change in growth rate or morphology. This change may be associated with subtle changes in brain functions, including behavioral and psychological changes, after exposure to low concentrations of organic mercury.
Conversion of cyclolaudenol to 24α‐ and 24β‐ethylsterols in the cucurbitaceae
Authors: Balliano Gianni , Caputo Otto , Viola Franca , Delprino Laura , Cattel Luigi 
Published: December 2006

Abstract[2‐3H]Cyclolaudenol was converted into α‐spinasterol, 24β‐ethylcholesta‐7,25‐dien‐3β‐ol and 24β‐ethylcholesta‐7,22,25‐trien‐3β‐ol by seedlings ofCucurbita maxima. As 24‐methylenecycloartanol is the obligatory precursor of 24‐ethylsterols, it can be assumed that the transformation of cyclolaudenol to 24‐methylenecycloartanol must have occurred. These results lead us to postulate the existence, in the Cucurbitaceae family, of an enzymatic system capable of isomerizing Δ25 alkylsterols into Δ25(28) sterols.
Regulation of phosphatidylinositol turnover, calcium metabolism and enzyme secretion by phorbol dibutyrate in neutrophils
Authors: Kramer Caroline M. , Franson Richard C. , Rubin Ronald P. 
Published: December 2006

AbstractThe action of the tumor promoter, phorbol 12,13‐dibutyrate (PDBu), on rabbit peritoneal and human neutrophils is associated with stimulation of14C‐arachidonic acid incorporation into phospholipids within 1–2 min. Stimulated14C‐arachidonate incorporation was relatively selective for phosphatidylinositol (PI) in rabbit neutrophils. In contrast, the secretory response of human neutrophils to PDBu coincided with stimulated label incorporation into phosphatidylserine (PS), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA) and PI. Significant increases in label incorporation were observed with PDBu concentrations as low as 2 nM, and the dose response of stimulated label incorporation paralleled that of evoked lysozyme secretion. A parallel, but partial, inhibition of PDBu‐stimulated PI labeling and enzyme release was observed after exposing rabbit neutrophils to calcium‐deprived medium, whereas calcium deprivation failed to significantly depress either of these stimulant actions of PDBu in human neutrophils. Further, in rabbit neutrophils PDBu elicited an increase in cell associated45Ca. However, PDBu was unable to promote the incorporation of32P orthophosphate into PI or enhance phospholipase A2 activity in broken cells. These findings suggest that one expression of the interaction between phorbol esters and their receptors on neutrophils involves the turnover of arachidonic acid in phospholipids. This stimulated turnover of arachidonate may be a critical step in the cascade of events associated with neutrophil activation.
Partial purification of a triacylglycerol lipase isolated from steelhead trout (Salmo gairdneri) adipose tissue
Authors: Sheridan Mark A. , Allen William V. 
Published: December 2006

AbstractA triacylglycerol (TG) lipase (EC 3.1.1.2), assayed by monitoring [1‐14C]‐oleic acid release from [carboxyl‐14C]‐triolein after liquid‐liquid partition of the fatty acid from the unhydrolyzed triacylglycerol substrate, was isolated and partially purified from steelhead trout adipose tissue. The TG lipase was resolved from contaminating lipoprotein lipase by heparin‐sepharose affinity chromatography and purified ca. 71‐fold over the original fraction. Optimal enzyme activity occurred at pH 7.5. The purified enzyme migrated on SDS‐polyacrylamide gels with an apparent molecular weight of 48,000.
Acyl‐acyl carrier protein as substrate of the acyltransferase of rat liver microsomes
Authors: Pugh E. L. , Kates M. 
Published: December 2006

AbstractAcyl‐acyl carrier protein (acyl‐ACP) can serve as well as acyl‐CoA as substrate of the 1‐acyl‐sn‐glycero‐3‐phosphocholine (1‐acyl‐GPC) acyltransferase of rat‐liver microsomes. The product of the acylation with either thioester substrate is predominantly phosphatidylcholine (PC) (92–95%). The acyl‐group transferred from either myristoyl‐CoA or myristoyl‐ACP is located at the C‐2 position of the phospholipid (PL). The apparent Km values for the myristoyl‐CoA and myristoyl‐ACP were 46 μM and 63 μM, and the corresponding apparent Vmax values were 1.0 and 1.6 nmol/min/mg. The rate of acylation with the acyl‐ACP was unaffected by the addition of free CoA‐SH. These data suggest that acyl‐CoA and acyl‐ACP are transferred to 1‐acyl‐GPC by the same or similar enzyme systems.
Tissue phospholipid fatty acid composition in the diabetic rat
Authors: Huang Y. S. , Horrobin D. F. , Manku M. S. , Mitchell J. , Ryan M. A. 
Published: December 2006

AbstractTissue phospholipid fatty acid compositions in streptozotocin‐induced diabetic rats were studied. The major changes in liver, plasma, erythrocyte and heart were increased proportions of linoleic and dihomo‐γ‐linolenic acids and a decreased proportion of aracchidonic acid. The latter was not significantly changed in phospholipids of kidney, adrenal gland and testis. Skin fatty acids in diabetic rats showed an increase in the proportion of arachidonic acid and a reduction in the proportion of linoleic acid. The fatty acid desaturating activity in diabetes may be regulated differently in different tissues.
Hepatic contribution to newly made fatty acids in adipose tissue in rats and inhibition of hepatic and extrahepatic lipogenesis from glucose by dietary corn oil
Authors: Baker N. , Mead J. , Kannan R. 
Published: December 2006

AbstractWe have reexamined an earlier rat study in which the authors concluded that 60 min after [U‐14C]‐glucose injection half of labeled fatty acids found in adipose tissue had been made in liver and then transported to the adipose tissue. We have shown that even under conditions in which the lipogenic role of the liver is optimized (fed‐refed rats on a fat‐free, high‐carbohydrate diet), almost none of the labeled fatty acids found in adipose tissue of rats 60 min after they were fed a labeled glucose test meal was derived from the liver. This conclusion was based experimentally on (a) the use of the blocking agent Triton WR 1339 to measure the total labeled triglyceride fatty acids (TGFA) synthesized and secreted by the liver in 60 min and (b) comparison of plasma TGFA‐14C data with radioactivity found in liver and in adipose tissue in 60 min. Without using Triton WR 1339, mathematical analysis of plasma TGFA‐14C following the glucose test‐meal leads one to the same conclusion: 97% of14C‐labeled fatty acids found in adipose tissue at 60 min was made in situ. Additional studies in rats established that the source of error in the earlier studies was an incorrect assumption that dietary corn oil could inhibit hepatic lipogenesis from glucose C without inhibiting fatty acid synthesis in adipose tissue. In our studies, 10% corn oil inhibited equally both hepatic and adipose tissue fatty acid synthesis from glucose C under conditions that precluded any significant transport of labeled TGFA‐14C from liver to adipose tissue.
Chain length dependent thermodynamics of saturated symmetric‐chain phosphatidylcholine bilayers
Authors: Mason Jeffrey T. , Huang Ching‐Hsien 
Published: December 2006

AbstractA molecular interpretation for the chain length dependent thermotropic behavior of saturated symmetric‐chain phosphatidylcholine bilayers is proposed. It is suggested that the bilayer interface region and conformationally inequivalent terminal ends of the fatty acyl chains perturb the packing associations of the rest of the hydrocarbon chains in the gel phase of the bilayer. These perturbing effects, which are seen to increase with decreasing acyl chain length, have been quantitatively defined by a perturbation parameter, P. The thermodynamic parameters of the thermal phase transition of these phosphatidylcholines are found to be linearly correlated to P and these linear relationships can be used to predict the minimum number of carbon atoms in the acyl chain necessary in order for a bilayer phase transition to occur.