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PubMed1997

Corynebacterium coyleae sp. nov., isolated from human clinical specimens.

Over a 5-year period, six isolates of a previously unknown nonlipophilic coryneform bacterium were isolated from human clinical specimens. The most characteristic phenotypic reactions of these isolates included slow fermentative acid production from glucose but no acid production from maltose and sucrose and a strongly positive CAMP reaction. Chemotaxonomic investigations revealed that meso-diaminopimelic acid and mycolic acids were present, that palmitic, oleic, and stearic acids were the predominant cellular fatty acids, and that the G + C content was 62 to 64 mol%, characteristics which are consistent with assignment to the genus Corynebacterium. Phenotypically, the unknown coryneform bacterium could be readily differentiated from all other Corynebacterium species. A 16S rRNA gene sequence analysis and quantitative DNA-DNA hybridization experiments demonstrated unambiguously that the unknown coryneform bacterium is a member of the genus Corynebacterium and is genotypically distinct from all other members of this genus. Based on phenotypic and genotypic findings, a new species, Corynebacterium coyleae sp.nov., is proposed. The type strain of C coylease is strain DSM 44184 (= CCUG 35014).

Adult↗
PubMed1996

Optimization of physiological lipid mixtures for barrier repair.

Three stratum corneum lipids, ceramides, cholesterol (CHOL), and free fatty acids (FA), are required for permeability barrier homeostasis. Recent studies have shown that application of one or two of these lipids to perturbed skin delays barrier recovery; only equimolar mixtures allow normal recovery. We asked here whether any physiological lipid mixtures improve barrier repair, as assessed by transepidermal water loss. Whereas an equimolar ratio of ceramides, CHOL, and FA (either the essential fatty acid, linoleic acid, or the nonessential FAs, palmitic or stearic acids) allows normal repair, further acceleration of barrier repair occurs as the ratio of any of these ingredients is increased up to 3-fold. Similar preliminary results were obtained in damaged human skin. Likewise, while acylceramides alone delay barrier recovery, acylceramides: CHOL mixtures within a specific range of molar rations dramatically improve barrier repair. Furthermore, glycosyl ceramides, sphingomyelin, and triglycerides substitute effectively for ceramides and FA, respectively, but neither phospholipids nor cholesterol esters substitute for FA and CHOL, respectively. These studies show the specific requirements of selected stratum corneum lipid mixtures for optimized barrier repair in murine skin, with further validation in human skin. Utilization of physiologic lipids according to these parameters could lead to new forms of topical therapy for dermatoses (e.g., psoriasis, atopic dermatitis, and irritant dermatitis) triggered by abnormal barrier function.

Adult↗
PubMed1977

Lipopeptidophosphoglycan from Trypanosoma cruzi. Amide and ester-linked fatty acids.

Lipopeptidophosphoglycan, extracted from whole cells of epimastigote forms of Trypanosoma cruzi, has now been shown to contain 12.6% of fatty acids in addition to the previously identified content of neutral sugars (60%), glucosamine (0.8%), peptide (9.5%) and acid-hydrolyzable phosphate (2%). The main fatty acids are palmitic (6.9%) and lignoceric (4.6%) acids. Stearic (0.55%), oleic (0.15%) and myristic (0.18%) acids were also found. One third of the fatty acids are bound in the lipopeptidophosphoglycan as esters (14 mmol%) and two thirds as amides (28 mmol%). Lignoceric acid was found to be bound only as amide. Two ninhydrin-positive compounds, obtained by chloroform extraction of a total acid hydrolysate of the lipopeptidophosphoglycan, were tentatively identified as sphingosine bases.

Amides↗
PubMed1979

Effect of free fatty acids on liposome susceptibility to imidazole antifungals.

The presence of free fatty acids in liposome model membranes sensitizes these membranes to the action of the imidazole antifungals, clotrimazole, micronazole, and sulconazole. Unsaturation of the fatty acids is an important variable; the effect of linoleic and oleic acids is much greater than that of stearic acid. The imidazoles differ somewhat in action, with clotrimazole potency greatest both on membranes with and without fatty acids. Sulconazole has very little activity on membranes without fatty acids even at the highest concentrations tested. The data are discussed with reference to the susceptibility of various cells to the imidazoles and the specificity of imidazole action. A modification of the enzymatic method generally used for assay of marker glucose with liposome systems is also presented.

Antifungal Agents↗
PubMed1991

Salt loads raise plasma fatty acids and lower insulin.

Some fatty acids are potent inhibitors of angiotensin binding and aldosterone production in adrenal glomerulosa cells and thereby may be involved in regulating salt and water balance. To study the possible regulation of fatty acids by salt, we measured the levels of unesterified fatty acids in plasma from patients subjected to extremes of dietary salt intake and saline infusion. Insulin and catecholamines, two known regulators of plasma fatty acids, also were measured. Infusion of 2 l saline over 4 hours caused the levels of most unesterified fatty acids to rise. Total unesterified fatty acids rose 60-100%. A high salt diet caused a smaller rise in total unesterified fatty acids (approximately 33%). In both instances, oleic and palmitoleic acids showed the greatest proportionate increases, whereas stearic acid was relatively unaffected. When salt loads were administered by either intravenous or dietary routes, plasma insulin levels fell by approximately 50%. Plasma norepinephrine increased after saline infusion but not during a high salt diet. Postsaline levels of fatty acids correlated inversely with postsaline levels of aldosterone, supporting a possible role for fatty acids as physiological regulators of the adrenal glomerulosa. A rise in plasma fatty acids and fall in insulin in response to salt loads could act in concert to increase sodium excretion, constituting a physiological mechanism contributing to salt and water balance.

Chromatography, High Pressure Liquid↗
PubMed1993

Pharmacological and pharmaceutical properties of freeze-dried formulations of egg albumin, indomethacin, olive oil, or fatty acids.

Formulations consisting of egg albumin, indomethacin (IND), and olive oil or fatty acids, were prepared by vigorous stirring using a high-speed homogenizer and subsequent freeze-drying. To confirm the anti-inflammatory properties and ulcerogenic effects of the formulations, we examined the action of the formulations on carrageenan-induced edema in rats as well as their ulcerogenic actions in the same species. Compared with IND alone, albumin-IND-olive oil (9:1:4.3), albumin-IND-linolenic acid (9:1:4.3), albumin-IND-linolic acid (9:1:4.3), albumin-IND-oleic acid (9:1:4.3), albumin-IND-stearic acid (9:1:4.3), and albumin-IND-tristearin (9:1:4.3) formulations all exhibited a more potent inhibitory effect on carrageenan-induced edema. In addition, the inhibitory effects on edema formation of an albumin-IND (9:1) complex was as strong as that of IND alone. These results suggested that the bioavailability of IND was increased by olive oil, fatty acid, and tristearin as absorbefacient agents. The increase in the bioavailability was evident from the fact that the mean plasma levels, maximum plasma levels (Cmax), and area under plasma concentration-time curve (AUC) values after oral administration of the albumin-IND-olive oil (9:1:4.3) formulation was significantly greater than that after administration of the drug alone. With respect to their ulcerogenic properties, the formulations were significantly less active than IND alone, suggesting that a reduction in the ulcerogenic activity of IND was by produced complexation with egg albumin.

Administration, Oral↗
PubMed1976

Fatty acids and fatty aldehydes of buffalo seminal plasma and sperm lipid.

Analysis of the fatty acids of total and neutral lipids, glycolipids, phospholipids and gangliosides of buffalo spermatozoa and seminal plasma showed that there were high levels of polyunsaturated acids. Neutral lipids were the richest in polyunsaturated acids (55% in spermatozoa and 61% in seminal plasma). The major saturated acid of all the principal classes was stearic acid and the major unsaturated acid was docosahexaenoic acid (22:6omega3) except in the neutral lipids in which it was arachidonic acid (20:4omega6). The major aldehyde was palmitaldehyde (16:0) in buffalo sperm lipids and docosanal (22:0) in seminal plasma. More than 50% of the total aldehydes was contributed by aldehydes with a chain length greater than 18 carbon atoms.

Aldehydes↗
PubMedDate not supplied

Procaine incorporation into human erythrocyte membrane--a spin label study.

The positioning of procaine among the components of human erythrocyte membranes was investigated by electron paramagnetic resonance (EPR) using several spin labelled molecules: fatty acids 5-, 12- and 16-doxyl-stearic acids (5DSA, 12DSA, 16DSA), procaine (SLP) and a quaternary ammonium salt (CAT4). It was proved that while procaine significantly modified EPR parameters of both CAT4 and 5DSA, it had no effect at the level of the twelfth or sixteenth carbon atom of the membrane lipid chains. Simultaneous incorporation of 5DSA and SLP and SLP in erythrocyte membranes revealed a shorter than 10 A distance between paramagnetic centers of 5DSA and SLP. It is inferred that procaine interacts with the membrane not only at lipid water interface, but also (at least) up to the fifth carbon atom of the hydrophobic tail of phopolipids. Procaine inclusion does not change the transition point (40 degrees C) at which a break appears in the temperature dependence of the erythrocyte volume, hence no strong interaction between the procaine and the cytoskeleton or the integral proteins responsible for this phase transition occurs. In the temperature domain of 25-42 degrees C, procaine seems to be freely diffusible within the membrane (Debye model can be applied).

Electron Spin Resonance Spectroscopy↗
PubMed1995

Liver microsomal phospholipid fatty acids behavior and its relationship to bilirubin UDP-glucuronyltransferase activity in bile duct ligated rats.

Phospholipid fatty acid composition and bilirubin UDP-glucuronyltransferase activity from liver microsomal membrane were studied in normal and in bile duct ligated rats. Incubation of normal microsomes with 15 microM bilirubin (considered as physiological concentration) yielded 60% bilirubin diglucuronide; in 2 days post-cholestatic rats, they showed 20% bilirubin diglucuronide which was undetectable in 8 days post-cholestatic group. When compared to controls, after 2 days of cholestasis, microsomal phospholipids showed a clear decrease in linoleic and arachidonic acids and an increment in palmitic and stearic acids. 8 days post-cholestatic rats presented a marked increase in palmitic, oleic and docosaexaenoic acids, while linoleic and arachidonic acids decreased. Cholestasis produced disturbances in microsomal phospholipids fatty acid composition; but these changes are unable to explain entirely the severe damage observed in bilirubin diglucuronide formation.

Animals↗
PubMed1985

Influence of triglycerides and free fatty acids in milk replacers on calf performance, blood plasma, and adipose lipids.

In a 4-wk study of 48 3-day-old calves we compared effects of feeding various fats or their free fatty acids in skim milk-powder based milk replacer, on calf performance, feed utilization, and blood plasma and adipose lipids. When fat was fed, calf performance and feed utilization were equivalent for tallow and coconut oil diets but markedly poorer for corn oil. Complete replacement (tallow) or one-half replacement (coconut and corn oils) of the fats with their free fatty acids reduced calf gains and feed efficiency. Tallow free fatty acids gave lower digestibilities of palmitic and stearic acid and reduced calcium absorption. Free fatty acids from both coconut and corn oils reduced diet palatability and intake; those from tallow and coconut oil markedly interfered (in vitro) with rennet clotting of milk replacers. The main lipid classes in blood plasma for all treatments were cholesteryl esters and phosphatidylcholine. High concentrations (56 to 87%) of linoleic acid occurred in cholesteryl esters for all diets despite low concentrations of linoleic acid in the tallow and coconut oil diets.

Adipose Tissue↗
PubMedDate not supplied

[Composition of lipids from yeast-like and mycelial cells of the fungus Mucor hiemalis, grown in the presence of 4-chloroaniline].

The fungus Mucor hiemalis, which is commonly thought to be monomorphic, produced two types of cells, yeastlike and mycelial, during growth in a medium containing 4-chloroaniline. Among the polar lipids of yeastlike cells, diphosphatidylglycerol was dominant, while phosphatidylcholine and phosphatidylethanolamine were present in minor amounts. Conversely, mycelial cells mainly contained phosphatidylcholine and phosphatidylethanolamine, whereas the content of diphosphatidylglycerol was low. The neutral lipids of yeastlike cells were dominated by diacylglycerides, sterols, and fatty acids. The content of triacylglycerides and sterol esters was low. Yeastlike cells contained higher amounts of saturated fatty acids and lower amounts of unsaturated fatty acids than the mycelium. The content of stearic acid in the fatty acids of the mycelium grown in the presence of 4-chloroaniline was as high as 25.3-29.9%.

Aniline Compounds↗
PubMed2005

[Changes in amino acid and fatty acid contents as well as activity of some related enzymes in apple fruit during aroma production].

Aroma volatiles from apple (Malus domestica Borkh. var. Starkrimson) fruit at different stages of maturity were collected by solid adsorbent-Tenax-GC and determined by thermodesorption and GC-MS. Production of propyl acetate, butyl acetate, ethyl 2-methyl-butanoate and total ester volatiles and changes in concentration of the precursors of aroma biosynthsis--free amino acids and fatty acids and activities of lipoxygenases (LOX) and alcohol acetyltransferase (AAT) in apple fruits during ripening were studied. The results showed that propyl acetate and total esters were very low when the endogenous ethylene formation of the fruit was very low. At the stage of the increase in ethylene production, the rate of formation of propyl acetate and total esters increased. Butyl acetate appeared at the beginning of ethylene rise and increased thereafter. Ethyl 2-methyl-butanoate was produced at the beginning of climacteric stage and then increased sharply (Figs.1). These facts suggest that the aroma production is closely related to ethylene production. Among the 14 free amino acids detected in fruit, isoleucine which is considered to be the biosynthetic precursor of some branched chain esters showed a great increase during fruit ripening while the others decreased or remained stable (Table 1). The accumulation of isoleucine suggested that isoleucine supply in fruit may not limit the biosynthesis of esters with branched chain alkyl groups. Concentrations of free fatty acids such as palmitic, linolenic, oleic, linoleic, stearic acids increased before the increase of aroma production, decreased with the increase of aroma production and showed an increase at postclimacteric stages (Fig.2). LOX activity increased at climacteric stages and declined rapidly thereafter. AAT activity increased sharply at the early stage of fruit maturity when the aroma was very low and remained at a stable high level during fruit ripening (Fig.3) indicating that the AAT activity is not the limiting factor for aroma formation in apple fruit.

Acetates↗
PubMed1975

Role of lamellar inclusions in surfactant production: studies on phospholipid composition and biosynthesis in rat and rabbit lung subcellular fractions.

Lamellar inclusion bodies in the type II alveolar epithelial cell are believed to be involved in pulmonary surfactant production. However, it is not clear whether their role is that of synthesis, storage, or secretion. We have examined the phospholipid composition and fatty acid content of rabbit lung wash, lamellar bodies, mitochondria, and microsomes. Phosphatidylcholine and phosphatidylglycerol, the surface-active components of pulmonary surfactant, accounted for over 80% of the total phospholipid in lung wash and lamellar bodies but for only about 50% in mitochondria and microsomes. Phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, and sphingomyelin accounted for over 40% of the total in mitochondria and microsomes but for only 6% in lung wash and 15% in lamellar bodies. The fatty acid composition of lamellar body phosphatidylcholine was similar to that of lung wash, but different from that of mitochondria and microsomes, in containing palmitic acid as a major component with little stearic acid and few fatty acids of chain length greater than 18 carbon atoms. The biosynthesis of phosphatidylcholine and phosphatidylglycerol was examined in the mitochondrial, microsomal, and lamellar body fractions from rat lung. Cholinephosphotransferase was largely microsomal. The activity in the lamellar body fraction could be attributed to microsomal contamination. The activity of glycerolphosphate phosphatidyltransferase, however, was high in the lamellar body fraction, although it was highest in the mitochondria and was also active in the microsomes. These data suggest that the lamellar bodies are involved both in the storage of the lipid components of surfactant and in the synthesis of at least one of those components, phosphatidylglycerol.

Animals↗
PubMed1991

Lipid compositions of intracellular membranes isolated from rat liver nodules in Wistar rats.

The mevalonate pathway gives rise to important end products for the regulation of growth and resistance to oxidative stress and is, consequently, of importance in carcinogenesis. In this study liver nodules were produced in Wistar rats by intermittent feeding with dietary 2-acetylaminofluorene, and the lipid compositions of isolated microsomes, mitochondria, and lysosomes were examined. The phospholipid compositions of these subfractions were unchanged compared to normal hepatic tissue, but the fatty acid patterns were altered, particularly in microsomes. An increase in the content of palmitic acid and a decrease in that of stearic acid were noted. The pattern of fatty acyl moieties on carbon atoms 1 and 2 of the glycerol backbone of phospholipids was unchanged in nodular tissue compared to normal liver. The amount of dolichol was significantly higher in microsomes and mitochondria, but not in lysosomes, and the relative amounts of longer polyisoprenoid compounds were increased in the liver nodules. The relative concentration of esterified dolichol was decreased and an enrichment in saturated fatty acids in this fraction could be observed. The cholesterol concentration was found to be lower in microsomes, but was unchanged in mitochondria and lysosomes, and the normally low concentration of cholesteryl esters was elevated somewhat in microsomes and lysosomes. The ubiquinone content of liver nodular mitochondria was unchanged, but increased 7-fold in microsomes and 2-fold in lysosomes. The alterations found in the lipid composition of liver nodules are significant and have functional implications in many cellular processes of proposed importance for the carcinogenic process, i.e., protein glycosylation cholesterogenesis, regulation of the mevalonate pathway, cellular oxidation-reduction state, and resistance to oxidative stress.

Animals↗
PubMed1988

[Use of the spin label method for studying the structure of the brain membranes in cats with streptomycin poisoning].

The structural changes in cat brain membranes under the injections of intramuscular streptomycin which is ototoxic antibiotic have been studied. The increase of membrane microviscosity in brain areas which are the direct projection of the auditory way has been revealed using fat acidic spin probe on the basis of stearic acid. The changes in membranes of other brain areas have not been found that exhibits a specific streptomycin influence on the auditory analyzer. The EPR spectra of the hydrocarbon spin label C12H25 localizing in near membrane region don't change in brain membranes of experimental animals compared with the normal ones.

Animals↗
PubMed1988

Size and composition of liver vitamin A reserves of human beings who died of various causes.

Postmortem livers from 77 "normal" persons, 37 patients with neoplastic disease, 10 subjects with liver insufficiency, and 7 infants were analysed for free and esterified retinol. The average concentrations of total vitamin A for the members of each group were 597, 551, 289, and 162 micrograms/g wet liver, respectively. Compared with corresponding control values, both cancer victims and patients with liver disease had significantly lower hepatic vitamin A levels. With regard to the composition of the liver vitamin A reserves, our results show that approximately 97% of this vitamin was present as retinyl ester. Additionally, minute amounts of retinol were also found in most of the liver specimens analysed. In "normal" subjects the major ester fraction recovered was palmitate/oleate followed by stearate and myristate/linoleate. By contrast, the second most abundant fatty acid in the retinyl ester fraction of cancer victims was myristic/linoleic acid together with significantly smaller quantities of stearic acid. In tissue samples obtained from patients with liver disorders, however, the myristate/linoleate fraction was increased and therefore nearly equal amounts of both retinyl stearate and myristate/linoleate were present.

Cause of Death↗
PubMed1986

[Preoperative increase in the plasma concentration of free fatty acids during minor elective interventions using a conventional anesthesia technic with enflurane].

Plasma concentrations of free fatty acids (FFApl) can be used as a parameter to measure stress. The present study aimed to evaluate the changes in the concentration of FFA during perioperative stress caused by minor elective surgery under a standard anaesthetic technique using enflurane. The premedication administered included heptabarbital on the preoperative night and morphine with promethazine prior to the transfer of the patient to the theatre. Blood samples for the analysis of FFA were obtained from 12 patients at the following times: 1 day preoperatively (control, c), prior to induction of anaesthesia (s1), following the administration of thiopentone (s2), following tracheal intubation (s3), 10 min after the commencement of enflurane administration (s4), following surgical incision (s5), intraoperatively (s6), following extubation (s7), 1 h after extubation (s8), and on the 1st postoperative day (s9). FFA were extracted from plasma with hexane and analysed in duplicate by a specific and sensitive gas-chromatographic assay with flame ionisation detection using pentadecanoic acid as the internal standard. All FFApl from the preoperative day (c) were within normal range. FFA concentrations at s1, s2, s3 and (to a lesser extent) at s4 were statistically significantly increased compared to control values. The maximum concentration of FFA in plasma occurred at s2. A decrease from this maximum was found in samples s4, s5 and s6 (the latter was the minimum intraoperative FFApl). The FFApl levels at s7, s8 and s9 were similar to control. A different response was found for each individual free fatty acid. The maximum increase ranged from 40% (stearic acid) to 300% (oleic acid).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1977

Treatment of oral estramustine phosphate (Estracyt) in prostatic carcinoma: influences on lipid and carbohydrate metabolism.

Estramustine phosphate (Estracyt), a combination of estradiol and nitrogen mustard given to males with prostatic carcinoma, had the same effect on serum lipids, lipoproteins, and serum phosphoglyceride fatty acid composition as ethynyl estradiol (Etivex). The characteristic effects on serum lipids caused by both drugs, i.e., a reduction in serum cholesterol and an increase in serum phospholipids, were apparently expressions for reduced low density lipoproteins and increased alpha-lipoproteins. Serum lecithin fatty acid composition revealed during the administration of both drugs a characteristic increase in palmitic acid (16:0) and a decrease in stearic acid (18:0), interpreted as evidence for a cholestatic, although subclinical, liver involvement. Similar changes have earlier been revealed in women given ethynyl estradiol; however, the increase in serum triglycerides and very low density lipoprotein cholesterol in young women was not duplicated in aged males with prostatic carcinoma. Furthermore, in aged males, the administration of these estrogens did not change carbohydrate metabolism but did produce an increase in adipose tissue lipoprotein lipase.

Adipose Tissue↗