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1.
Docosahexaenoic acid (DHA; 22∶6n−3) is found in extremely high levels in human ejaculate with the majority occurring in the spermatozoa. However, the relative concentration of DHA and other fatty acids, in blood serum, seminal plasma, and spermatozoa of asthenozoospermic vs. normozoospermic individuals is not known. We analyzed the phospholipid fatty acid composition of blood serum, seminal plasma, and spermatozoa of normozoospermic men and asthenozoospermic men in order to determine if DHA levels, as well as the levels of other fatty acids, differed. The serum phospholipid DHA levels were similar in the two groups, suggesting similar intakes of dietary DHA. On the other hand, seminal plasma levels of DHA (3.0 vs. 3.7%) and total polyunsaturated fatty acids (PUFA) (11.8 vs. 13.5%) were significantly lower in asthenozoospermic vs. normozoospermic men, respectively, while 18∶1 (19.0 vs. 16.8%) and monounsaturated fatty acids (MUFA) (24.2 vs. 21.7%) were significantly higher in the asthenozoospermic vs. the normozoospermic men. Spermatozoa from asthenozoospermic men had higher levels of 18∶1, 20∶0, 22∶0, 22∶1, and 24∶0 than sperm from normozoospermic men, and lower levels of 18∶0 and DHA (8.2 vs. 13.8%). Furthermore, total MUFA (19.3 vs. 16.5%) was higher and total PUFA (19.0 vs. 24.0%), n−3 fatty acids (9.3 vs. 14.6%), and the ratio of n−3 to n−6 fatty acids (1.0 vs. 1.6) were lower in the asthenozoospermic men. Therefore, in asthenozoospermic individuals, lower levels of DHA in the seminal plasma, but not in the blood serum, mimic the decreased concentrations of DHA in the spermatozoa. This suggests that the lower concentrations of spermatozoon DHA in these individuals are due not to dietary differences but to some type of metabolic difference in the asthenozoopermic men.  相似文献   

2.
Kuksis  A.  Myher  J. J.  Marai  L.  Little  J. A.  McArthur  R. G.  Roncari  D. A. K. 《Lipids》1986,21(6):371-377
The bulk of the plasma plant sterol in phytosterolemia occurs in the esterified form and is carried mostly in the low and high density lipoproteins. We have determined the fatty acid composition of the individual plasma steryl esters from a newly discovered subject with phytosterolemia and xanthomatosis. For this purpose the intact steryl esters were subject to high temperature gas liquid chromatography (GLC) on a polar capillary column, which separated the major esters on the basis of molecular weight and degree of unsaturation of the fatty acids. The saturated and unsaturated sterols esterified to saturated, monoenoic, dienoic and tetraenoic fatty acids were identified by GLC analysis of the sterol moieties of the corresponding AgNO3-TLC fractions of the steryl esters. The GLC results were confirmed by reversed phase high performance liquid chromatography combined with mass spectrometry via direct liquid inlet interface. It was found that, in general, each fatty acid was esterified to the same complement of sterols, and that the esterified sterols possessed a composition comparable to that of the free plasma sterols, which was comprised of about 75% cholesterol, 6% campesterol, 4% 22,23-dihydrobrassicasterol and 15% β-sitosterol. The fatty acid composition of the steryl esters differed from that of the 2-position of the plasma phosphatidylcholines, which contained significantly less palmitic and oleic and more linoleic acid. On the basis of these results and a review of the literature it is suggested that the plasma cholesteryl and plant steryl esters in phytosterolemia originate from both synthesis in plasma via the lecithin-cholesterol acyltransferase and synthesis in tissues via the acylCoA-cholesterol acyltransferase.  相似文献   

3.
The fatty acid composition of ceramides has been determined in kidney and cerebellum of a patient with Farber's disease, which is characterized by ceramidase deficiency. Farber cerebellum and kidney contained a five- and ten-fold excess, respectively, of free ceramides. The nonhydroxy fatty acid patterns of the ceramides from Farber kidney and cerebellum showed considerable similarities to those from control tissues, whereas large amounts of ceramides containing hydroxy fatty acids are found in Farber's disease tissues.  相似文献   

4.
The purpose of the present study was to determine whether increased levels of platelet-activating factor (PAF) type activity can be detected in plasma from patients with septicemia and other diseases. A level of PAF below 0.5 ng/mL of plasma was considered normal. We found that plasma from a patient with adverse anaphylactoidic reaction to intravenous analgetics contained 2.1 ng PAF/mL. In seven patients with septicemia, including urosepsis, endocarditis and peritonitis, and with positive blood culture, increased plasma PAF levels (1–20 ng PAF/mL) were observed. Other patients with clinical indications of septicemia had negative blood cultures and/or increased levels of C-reactive protein (CRP). Yet, in the plasma from these patients, no increased PAF levels were detected under the assay conditions used. Two patients with allergic asthma, requiring treatment with steroids, had no measurable plasma PAF. In the plasma from a patient with idiopathic thrombocytopenic purpura (ITP) only an “endogenous” inhibitor of PAF induced platelet aggregation was initially observed. In spite of this, the patient responded to treatment with the PAF antagonist WEB 2086 with a dramatic increase in platelet count (Lohmannet al., Lancet ii, 1147, 1988). Thereafter, also increased PAF levels (3.3 ng PAF/mL) were detected in plasma, although some “endogenous” inhibitor of PAF was still present. In conclusion, increased PAF levels in plasma from patients support a role of PAF in certain human disease states, such as in anaphylactoid reaction, sepsis and septic shock. The type, relevance and specificity of endogenous inhibitors of PAF deserve further study. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989.  相似文献   

5.
The objective of this study was to examine compositional and quantitative changes in fatty acids of plasma components and red blood cell phospholipids (PL) immediately following and during recovery from burn injury. Subjects (n=10) with >10% total body surface area burn had blood drawn at specific timepoints (0 to >50 d) following burn injury. Fatty acid composition of red blood cell PL and plasma PL, cholesteryl esters (CE), and triglycerides was determined using gas-liquid chromatography after separating each fraction from extracted lipids by thin-layer chromatography. Total plasma PL and CE in burn patients were lower than in healthy control subjects with reduced 20∶4n−6, n−6, and n−3 fatty acids and higher levels of monounsaturated and saturated fatty acids early after burn. CE levels remained half that of healthy control values up to 50 d post-burn. Red blood cell PL had decreased 20∶4n−6 content and profiles similar to that of an essential fatty acid deficiency early after burn. These results suggest an impairment in lipoprotein and polyunsaturated fatty acid metabolism in the early post-burn period. Lower levels of 20∶4n−6 and n−3 fatty acids in every plasma fraction suggest increased use of these fatty acids for wound healing and immune function following burn injury. Further work is needed to determine the ability of burn patients to utilize essential fatty acids in order to design nutritional intervention that promotes wound healing and immunological functions consistent with recovery in these patients.  相似文献   

6.
从大型化和废热利用两方面,对国内外硫磺制酸进行对照分析,认为进一步加速实施大型化和提高度热利用率是我国硫磺制酸的发展趋势。  相似文献   

7.
The effects of dietarytrans fatty acids on the fatty acid composition of the brain in comparison with other organs were studied in 3-wk-old suckling piglets. In Experiment (Expt.) 1 the piglets were delivered from sows fed partially hydrogenated fish oil (PHFO) (28%trans), partially hydrogenated soybean oil (PHSBO) (36%trans) or lard (0%trans). In Expt. 2 the piglets were delivered from sows fed PHFO, hydrogenated fish oil (HFO) (19%trans) or coconut fat (CF) (0%trans) with two levels of dietary linoleic acid (1 and 2.7%) according to factorial design. In both experiments the mother's milk was the piglets' only food. The level of incorporation oftrans fatty acids in the organs was dependent on the levels in the diets and independent of fat source (i.e., PHSBO, PHFO or HFO). Incorporation oftrans fatty acids into brain PE (phosphatidylethanolamine) was non-detectable in Expt. 1. In Expt. 2, small amounts (less than 0.5%) of 18∶1trans isomers were found in the brain, the level being slightly more on the lower level of dietary linoleic acid compared to the higher. In the other organs the percentage of 18∶1trans increased in the following order: heart PE, liver mitochondria PE, plasma lipids and subcutaneous adipose tissue. Small amounts of 20∶1trans were found in adipose tissue and plasma lipids. Other very long-chain fatty acids from PHFO or HFO (i.e., 20∶1cis and 22∶1cis+trans) were found in all organ lipids except for brain PE. Dietarytrans fatty acids increased the percentage of 22∶5n−6 in brain PE. Except for the brain and the heart, dietarytrans fatty acids reduced the percentage of saturated fatty acids and increased the percentage of monoenoic acids (includingtrans). The overall conclusion was that dietarytrans fatty acids had no noticeable effect on the brain PE composition but slight to moderate effects on the fatty acid profile of other organs of suckling piglets.  相似文献   

8.
Steers were given diets containing formaldehyde-treated casein-safflower oil supplements, in which the constituent 18∶2 was protected from ruminal hydrogenation. A similar group was given unsupplemented diets. The fatty acid compositions of plasma, liver, muscle and adipose tissue lipids were determined in both groups of cattle after 0, 2, 4 and 8 weeks of experimentation. The proportion of 18∶2 in the triglycerides was markedly increased on feeding the supplement and the rate of incorporation into the plasma triglycerides was higher than that in the triglycerides of muscle and adipose tissue. Associated with this increase there were compensatory decreases in the proportions of 16∶0 and 18∶1 but no consistent change in the proportion of 18∶0. The proportion of 18∶2 in the plasma phospholipids and cholesteryl esters was initially much higher than in the triglycerides and this was further increased by feeding the safflower oil supplement. A linear relationship existed between the proportion of 18∶2 in the phospholipids and cholesteryl esters of plasma. The supplement also caused substantial increases in the proportion of 18∶2, both in phospholipids from liver and muscle and in cholesteryl esters from liver, and there were compensatory decreases in the proportions of other unsaturated fatty acids, e.g., 18∶1, 18∶3, 22∶6. These studies demonstrate that when ruminal hydrogenation was circumvented by feeding formaldehyde-treated casein-safflower oil particles, the linoleic acid was absorbed and the pattern of incorporation into plasma and tissue lipids was similar to that in nonruminants.  相似文献   

9.
10.
Variation in the fatty acid composition of fasting plasma lipids and of cholesteryl esters was studied in 69 sets of adult male twins and 25 of their brothers. Genetic variances were estimated using the twin model. In general, monozygotic (MZ) twins were characterized by the smallest within-pair variance, and brothers of twins by the largest. Variation within dizygotic pairs fell intermediate to that of MZ twins and brothers. The present study did not reveal consistent significant (P<0.05) genetic variation in plasma fatty acids from total plasma lipids or cholesteryl esters.  相似文献   

11.
This paper reports the fatty acid and triacylglycerol (TAG) compositions of five Amaranthus accessions (RRC1011, R149, A.K343, A.K432, and A. K433) representing two species and a cross between one of these and a third species. Seed oils of these were analyzed by gas chromatography and reversed-phase high-performance liquid chromatography, and their compositional properties compared with buck-wheat (Fagopyrum esculentum), corn (Zea mays), rice bran (Oryza sativa), soybean (Glycine max L. Merr.), sesame (Sesamum indicum), quinoa (Chenopodium quinoa), and cottonseed (Gossypium hirsutum) oils. All Amaranthus accessions were relatively high in palmitic (21.4–23.8%) and low in oleic (22.8–31.5%) and linolenic (0.65–0.93%) acids when compared to most of the grain and seed oils. The fatty acid composition of Amaranthus accessions K343, K433, and K432 (group I) were different from R149 and RRC1011 (group II) in mono and polyunsaturated fatty acids, but the saturate/unsaturate (S/U) ratios were very similar. All Amaranthus accessions were similar in TAG type, but showed slight differences in percentage. High similarities in UUU, UUS, and USS composition were observed among Amaranthus K343, K433 and K432, and between R149 and RRC1011. The fatty acid compositions of Amaranthus oil (group I) and cottonseed oil were similar, but their TAG compositions were different. The grain and oilseed oils were different from each other and from the Amaranthus accessions oils in terms of fatty acid composition, S/U, and TAG ratios. The UUU, UUS, and USS percentages were very diverse in grain and seed oils. The percentages of squalene in the TAG sample from the Amaranthus accessions were 8.05% in K343, 11.10% in K433, 11.19% in K432, 9.96% in R149, and 9.16% in RRC1011. Squalene was also tentatively identified in quinoa and ricebran oils at levels of 3.39 and 3.10%, respectively.  相似文献   

12.
The two major phospholipid classes, namely, phosphatidylethanolamines (PE) and phosphatidylcholines (PC), were studied in four different regions of human brain,i.e., in frontal gray matter, frontal white matter, hippocampus and in pons. The fatty acid (FA) compositions of these phospholipids were found to be specific for the different regions. PC contains mostly saturated and 18∶1 FA, while PE is rich in polyunsaturated FA. Aging has no influence on the FA compositions, while in Alzheimer’s disease (AD) PE is modified in all four regions, particularly in frontal gray matter and in hippocampus. The abundance of the major monounsaturated FA of PE, 18∶1, is not significantly altered in Alzheimer’s disease, but there is a substantial increase in the relative amounts of the saturated components 14∶0, 16∶0 and 18∶0. This is paralleled by a decrease in the polyunsaturated FA 20∶4, 22∶4 and 22∶6. It is not clear whether the changes observed are specific for AD. Changes in saturated/polyunsaturated FA ratio are likely to influence cellular function, which in turn may cause certain neural deficiencies. The findings do not support the hypothesis that AD reflects an accelerated aging process.  相似文献   

13.
Normal healthy male volunteers (n=10) were fed diets (high-AA) containing 1.7 g/d of arachidonic acid (AA) for 50 d. The control (low-AA) diet contained 210 mg/d of AA. Dietary AA had no statistically significant effect on the blood cholesterol levels, lipoprotein distribution, or apoprotein levels. Adipose tissue fatty acid composition was not influenced by AA feeding. The plasma total fatty acid composition was markedly enriched in AA after 50 d (P<0.005). The fatty acid composition of plasma lipid fractions, cholesterol esters, triglycerides, free fatty acids, and phospholipid (PL) showed marked differences in the degree of enrichment in AA. The PL plasma fraction from the subjects consuming the low-AA diet contained 10.3% AA while the subjects who consumed the high-AA diet had plasma PL fractions containing 19.0% AA. The level of 22:4n-6 also was different (0.67 to 1.06%) in the plasma PL fraction after 50 d of AA feeding. After consuming the high-AA diet, the total red blood cell fatty acid composition was significantly enriched in AA which mainly replaced linoleic acid. These results indicate that dietary AA is incorporated into tissue lipids, but selectively into different tissues and lipid classes. Perhaps more importantly, the results demonstrate that dietary AA does not alter blood lipids or lipoprotein levels or have obvious adverse health effects at this level and duration of feeding.  相似文献   

14.
Male rats were fed on a fat-free diet for 8 weeks and then switched to diets containing 10% hydrogenated coconut oil (HCO), safflower oil (SFO) or evening primrose oil (EPO). Half of each group was also given 1% of cholesterol in the diet. After 5 further weeks, plama, red cell and liver fatty acids were measured in the various lipid fractions. Plasma and liver cholesterol also were estimated. In almost all fractions and on all three diets, feeding cholesterol led to accumulation of the substrates of desaturation reactions and to deficits of the products of these reactions. The results were consistent with inhibition of Δ-6, Δ-5 and Δ-4 desaturation of n−6 essential fatty acids. Since the diets were deficient in n−3 fatty acids, levels were very low but were also consistent with inhibition of desaturation. In contrast, cholesterol had relatively less consistent effects on 20∶3n−9, suggesting that desaturation of n−9 fatty acids was less inhibited. Plasma cholesterol levels rose sharply in the HCO and SFO groups but not at all in the EPO group. EPO contains the product of Δ-6 desaturation, 18∶3n−6, suggesting that conversion of linoleic acid to 18∶3n−6 and possibly to further metabolites may be important for the cholesterol-lowering effect of polyunsaturates.  相似文献   

15.
Trans fatty acids from hydrogenated vegetable and marine oils could be as hypercholesterolemic and atherogenic as saturated fatty acids. Hence, it is important to know the fatty acid composition in major food contributors, e.g., margarines and shortenings. In 1992 margarines were examined, and in 1995 brands covering the entire Danish market were examined. Significant amounts oftrans-18∶1 were found only in hard margarines (mean: 4.2±2.8%) and shortenings (mean: 6.8 ±3.1%), whereas the semisoft and soft margarines contained substantially lesstrans-18∶1 in 1995 than in 1992. Where marine oils had been used to a larger degree the meantrans-monoenoic content was about 15%, of which close to 50% was made up of long-chain (C20 and C22)trans fatty acids. A note-worthy decrease in the content oftrans-18∶1 had occurred for the semisoft margarines, from 9.8±6.1% in 1992 to 1.2±2.2% in 1995. Calculated from sales figures, the supply oftrans-18∶1 plus saturated fatty acids from margarines had decreased over this three-year period by 1.4 g/day, which has been replaced bycis monounsaturated and polyunsaturated fatty acids.  相似文献   

16.
Summary Relative values for the carotene-stabilizing effects in edible oil solutions of a number of antioxidants, alone and in various combinations, have been determined and are presented. One of the more promising for this purpose is nordihydroguaiaretic acid. When this antioxidant is used together with phospholipid or citric acid, its effectiveness is enhanced. Addition of alpha-tocopherol to oils containing only traces of this antioxidant causes a significant increase in carotene stability, and its sparing effect on carotenein vivo (8) would further add to the desirability of its use in such oil solutions of carotene. In refined cottonseed oil, carotene destruction occurred concurrently with the accumulation of peroxides. In the more saturated oils, carotene destruction occurred before much peroxide was detected in the oils. Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.  相似文献   

17.
The effects of dietarytrans fatty acids on tissue fatty acid composition were studied in newborn piglets delivered from sows fed partially hydrogenated fish oil (PHFO) (28%trans) or partially hydrogenated soybean oil (PHSBO) (36%trans) in comparison with lard (0%trans) from 3 wk of age and through gestation in Experiment 1, or fed PHFO or “fully” hydrogenated fish oil (HFO) (19%trans) in comparison with coconut oil (CF) (0%trans) with two levels, 1 and 2.7%, of dietary linoleic acid from conception through gestation in Experiment 2. The piglets were sampled immediately after delivery, without having access to mothers' milk. Incorporation oftrans fatty acids into brain PE (phosphatidylethanolamine) were non-detectable or very low (less than 0.1%). The incorporation of 18∶1trans into heart-PE, liver mitochondria-PE, total plasma lipids and adipose tissue was low, and 20∶1trans was not detected. Dietarytrans fatty acids had no consistent effects on the overall fatty acid composition of the different tissue lipids. It is conclude thattrans fatty acids from PHFO, HFO and PHSBO have no significant effects on the fatty acid accretion in the fetal piglet.  相似文献   

18.
The fatty acid composition of erythrocytes, platelets, and serum lipids was compared between subjects who had been eating a strict uncooked vegan diet (“living food”) for years and omnivore controls. The vegan diet contains equal amounts of fat but more monounsaturated and polyunsaturated and less saturated fatty acids than the mixed diet of the control group. In vegans, the proportion of linoleic acid was greater in all lipid fractions studied. Also, the levels of other n−6 fatty acids were greater, with the exception of arachidonic acid levels, which were similar in most fractions. In erythrocytes, platelets and serum phospholipid fractions, this increase was mainly at the expense of the n−3 fatty acids. The proportions of eicosapentaenoic and docosahexaenoic acid were only 29–36% and 49–52% of those in controls, respectively. In vegans the ratio of n−3 to n−6 fatty acids was only about half that in omnivores. In addition to the lower levels of n−3 fatty acids, the proportions of palmitic and stearic acids were lower in serum cholesteryl esters, triglycerides and free fatty acids of vegans. The proportion of oleic acid was slightly lower only in serum cholesteryl esters and erythrocyte phosphatidylserine. The results show that, in the long term, the vegan diet has little effect on the proportions of oleic and arachidonic acids, whereas the levels of n−3 fatty acids are depressed to very low levels with prolonged consumption of the high linoleic and oleic acid components of this diet.  相似文献   

19.
The effects of dietary cis and trans α-linolenic acid (18∶3n−3) on the FA composition of plasma, red blood cell, and liver phospholipids were studied in newborn piglets. Animals were fed for 14 d with one of three diets: a control diet (group A) containing cis 18∶3n−3 at a level of 2.0% of total FA, a diet (group B) in which a part of the 18∶3n−3 acid was isomerized (1.3% of cis 18∶3n−3 and 0.7% of trans 18∶3n−3), or a diet (group C) with 2.0% cis 18∶3n−3 and 0.7% trans 18∶3n−3. Feeding animals with diets containing trans 18∶3n−3 resulted in the presence of trans isomers of 18∶3n−3, trans isomers of EPA, and trans isomers of DHA in phospholipids; however, the level of total trans n−3 PUFA in tissues was less than 0.3% of total tissue FA. In group B, the reduction of dietary amounts of cis 18∶3n−3 was associated with a decrease in individual and total cis n−3 PUFA. In contrast, in group C there was no decrease in tissue n−3 PUFA despite the increased dietary level of trans 18∶3n−3. These results suggest that the isomerization of a part of dietary n−3 PUFA, leading to the reduction of their levels in the diet, could induce a decrease in n−3 PUFA in phospholipids. The physiological effects of trans PUFA are not known and should be considered in future studies.  相似文献   

20.
The China-chestnuts (Sterculia monosperma, Ventenat) were examined for their fatty acid composition by gas liquid chromatography, infrared and nuclear magnetic resonance spectroscopy. The oil in nuts contained cyclopropene fatty acids (CPFA) determined as silver nitrate derivatives of their esters. The values (area %) for the major fatty acids as methyl esters were 23.47% C16:0, 1.25% C16:1, 2.56% C18:0, 24.89% C18:1, 18.24% C18:2, 5.40% dihydrosterculic, 3.21% C18:3 + C20:0 and 19.15% sterculic. The proportion of CPFA in the oil did not decrease upon cooking the nuts.  相似文献   

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