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1.
Eur J Mass Spectrom (Chichester) ; 20(2): 199-205, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24895781

RESUMEN

Chemical compositions of volatile and semi-volatile components in green and fermented leaves of Bergenia crassifolia L. were studied. Leaf components were identified using gas chromatography with low resolution mass spectrometry and direct analysis in real time (DART) high resolution mass spectrometry with an ID-CUBE ion source. Phytol, nerolidol, geraniol, linalool, alpha-bisabolol, alpha-bisabololoxide B, alpha-cadinol, delta-cadinene, alpha-terpineol and several other marker compounds of special interest were defined, for which the process of fermentation significantly changed their content in the leaves. Low resolution El GC-MS and ID-CUBE DART-HRMS were found to be complementary methods, as they provide different information, helpful to increase the confidence of identification.


Asunto(s)
Algoritmos , Análisis de los Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Hojas de la Planta/química , Saxifragaceae/química , Compuestos Orgánicos Volátiles/análisis , Color , Sistemas de Computación , Fermentación
2.
Artículo en Inglés | MEDLINE | ID: mdl-20206485

RESUMEN

The effects of canola-type rapeseed oil (RSO) on serum lipids, plasma fibrinogen, lipid oxidation and fatty acids were studied in three groups of subjects, two of which had not been consuming fish in their habitual diets. Forty-two volunteers (35 women, 7 men, 16-62 years) replaced fat with RSO for 6 weeks in a parallel design. The average cholesterol and fibrinogen concentrations were 5.0 mmol/l and 2.6 g/l, respectively. The intake of alpha-linolenic acid (alpha-LLA) was doubled. Efficient competitive inhibition by alpha-LLA was seen as a decrease in long-chain (LC) n-6 PUFA at 3 weeks. Elevated fibrinogen (2.6-3.9 g/l) decreased by 0.95 g/l at 6 weeks. Docosahexaenoic acid (22:6n-3) in plasma phospholipids increased at low fibrinogen levels only. The associations and changes in plasma C18 and LC PUFA followed the competitive and metabolic principles of the body, and especially in the case of n-3 PUFA according to the recycling pathway.


Asunto(s)
Ácidos Grasos Monoinsaturados/administración & dosificación , Ácidos Grasos Omega-6/sangre , Fibrinógeno/análisis , Ácido alfa-Linolénico/efectos adversos , Adolescente , Adulto , Femenino , Fibrinógeno/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Fosfolípidos/sangre , Aceite de Brassica napus , Factores de Tiempo , Ácido alfa-Linolénico/administración & dosificación
3.
Phys Med Biol ; 55(4): 1157-76, 2010 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-20107250

RESUMEN

An extensive study on specific absorption rate (SAR) covering 720 simulations and 15 voxel models (18-105 kg) has been performed by applying the parallel finite-difference time-domain method. High-resolution whole-body models have been irradiated with plane waves from 300 MHz to 5 GHz by applying various incoming directions and polarizations. Detailed results of whole-body SAR and peak 10 g SAR are reported, and SAR variation in the dB scale is examined. For an adult, the effect of incoming direction on whole-body SAR is larger in the GHz range than at around 300-450 MHz, and the effect is stronger with vertical polarization. For a child (height approximately 1.2 m), the effect of incoming direction is similar as for an adult, except at 300 MHz for horizontal polarization. The effect of the phantom (18-105 kg) on whole-body SAR is larger at around 2-5 GHz and at vertical 300 MHz (proximity of whole-body resonance for the child) than at around horizontal 300-900 MHz. Body posture has little effect on whole-body SAR in the GHz range, but at around 300-450 MHz, one may even expect a 2 dB rise in whole-body SAR if posture is changed from the standing position. Posture affects peak 10 g SAR much more than whole-body SAR. The polarization of the incident electric field may have an effect of several dB on whole-body SAR. Between 2 and 5 GHz for adults, whole-body SAR is higher for horizontal than for vertical polarization, if the incoming direction is in the azimuth plane. In the GHz range, horizontal polarization gives higher whole-body SAR, especially for irradiation from the lateral direction. A comparison between homogeneous and heterogeneous models was done. A homogenized model underestimates whole-body SAR, especially at approximately 2 GHz. The basic restriction of whole-body SAR, set by ICNIRP, is exceeded in the smallest models ( approximately 20 kg) at the reference level of exposure, but also some adult phantoms are close to the limit. The peak 10 g SAR limits were never exceeded in the studied cases. The present ICNIRP guidelines should be revised by lowering the reference levels, especially at around 2-5 GHz.


Asunto(s)
Simulación por Computador , Modelos Biológicos , Postura , Radiación , Adulto , Niño , Femenino , Humanos , Masculino , Fantasmas de Imagen , Dosis de Radiación
4.
Phys Med Biol ; 53(2): 445-52, 2008 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-18184998

RESUMEN

In this paper, the anatomically realistic body model Zubal is exposed to a plane wave. A finite-difference time-domain (FDTD) method is used to obtain field data for specific-absorption-rate (SAR) computation. It is investigated how the FDTD resolution, power-loss computation method and positioning of the material voxels in the FDTD grid affect the SAR results. The results enable one to estimate the effects due to certain fundamental choices made in the SAR simulation.


Asunto(s)
Carga Corporal (Radioterapia) , Modelos Biológicos , Efectividad Biológica Relativa , Recuento Corporal Total/instrumentación , Recuento Corporal Total/métodos , Simulación por Computador , Transferencia de Energía , Exposición a Riesgos Ambientales , Diseño de Equipo , Análisis de Falla de Equipo , Análisis de Elementos Finitos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Plant Cell Rep ; 23(10-11): 683-91, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15365763

RESUMEN

Solanum acaule Bitt., a wild potato species, is closely related to cultivated potato (Solanum. tuberosum L.). Incorporation of desirable traits from allotetraploid [2n=4x=48, 2 endosperm balance number (EBN)] S. acaule (acl) into autotetraploid (2n=4x=48, 4EBN) S. tuberosum (tbr) is difficult due to incongruity boundaries. In this study, three hybrid combinations, each with a specific genome constitution, were produced through protoplast fusion: (1) hexaploid 2x acl (+) 4x tbr, (2) tetraploid 2x acl (+) 2x tbr, and (3) hexaploid 4x acl (+) 2x tbr hybrids. In terms of glycoalkaloid aglycones, the hybrids produced demissidine, tomatidine and solanidine, similarly to the S. acaule parental species, but S. tuberosum synthesised only solanidine. Inoculations with Clavibacter michiganensis ssp. sepedonicus (Cms), which is the causal agent of bacterial ring rot in potato, yielded significantly lower total glycoalkaloid aglycone accumulation both in S. acaule plants and in interspecific hybrids in comparison with the corresponding mock-inoculated plants. However, in S. tuberosum the aglycone levels were either higher or unchanged as a result of infection by Cms. To incorporate the desirable traits of the interspecific somatic hybrids into 4EBN S. tuberosum, sexual backcrosses were carried out. The hexaploid 4x acl (+) 2x tbr hybrids with the hypothetical 4EBN showed the greatest capacity to undergo backcrosses with S. tuberosum.


Asunto(s)
Actinomycetales/fisiología , Enfermedades de las Plantas/microbiología , Alcaloides Solanáceos/metabolismo , Solanum tuberosum/microbiología , Solanum/microbiología , Hibridación Genética , Regeneración , Solanum/metabolismo , Solanum/fisiología , Solanum tuberosum/metabolismo , Solanum tuberosum/fisiología , Técnicas de Cultivo de Tejidos
6.
Cent Eur J Public Health ; 12 Suppl: S39-40, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15141974

RESUMEN

2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay and nitroprusside assay were used for in vitro study of antiradical/scavenger activity of Philadelphus coronarius petal substances. The results obtained can be used as the basis for further studies of this type of the biological effects in the plant.


Asunto(s)
Extractos Vegetales/farmacología , Plantas Medicinales/química , Animales , Cromatografía Líquida de Alta Presión , Colorimetría , Flavonoides/análisis , Radicales Libres , Fenoles/análisis , Análisis de Regresión
7.
Cent Eur J Public Health ; 12 Suppl: S89-93, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15141992

RESUMEN

The worm Tubifex tubifex Müll. (Tubificideae, Oligochaeta) is a suitable organism for the research of the biological effect of various pollutants. This pilot study deals with the responds of the organism to the treatments of two photosensitizers (bengal rose B, quinidine) and UVA radiation. The activity of the photosensitizers was evaluated by the comparison of the surfaces of tested worms and dark controls. The results showed that T. tubifex Müll. could be a suitable organism for the studies of phototoxicity. This species demonstrated relatively strong sensitivity to the effect of the selected photodynamically active substances.


Asunto(s)
Oligoquetos , Fármacos Fotosensibilizantes/toxicidad , Quinidina/toxicidad , Rosa Bengala/toxicidad , Animales , Microscopía Electrónica de Rastreo
8.
J Comb Chem ; 3(6): 542-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11703149

RESUMEN

The Vilsmeier formylation has been introduced for the solid-phase functionalization of five different 2-carboxyindoles. The aldehyde functionality has been utilized in the preparation of O-benzylhydroxyureas.


Asunto(s)
Técnicas Químicas Combinatorias , Hidroxiurea/síntesis química , Indoles/síntesis química , Urea/análogos & derivados , Urea/síntesis química , Ácidos Carboxílicos/síntesis química , Diseño de Fármacos , Formiatos/química , Tecnología Farmacéutica
9.
Comb Chem High Throughput Screen ; 4(6): 521-4, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11562256

RESUMEN

As part of an ongoing lead discovery project we have developed a convenient method for the modification and substitution of indole moieties at the 3-position. Selective bromination of three different 2-carboxyindoles was followed by Suzuki cross-coupling with aryl and heteroaryl boronic acids on a Merrifield resin solid-phase. After column chromatography, yields of the 3- substituted indoles ranged from 42-98%.


Asunto(s)
Bromo , Indoles/química , Indoles/síntesis química , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-Actividad
10.
J Chromatogr B Biomed Sci Appl ; 754(2): 437-45, 2001 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-11339287

RESUMEN

An HPLC method with evaporative light-scattering detection (ELSD) was optimized and validated for the simultaneous quantitation of cholesteryl esters (CEs), triacylglycerols (TGs), free cholesterol (FC) and phosphatidylcholine (PC) in human plasma. The separation of CEs from TGs, the most variable plasma lipid class, was improved by speeding up the gradient steps and by increasing the re-equilibration time between runs. The calibrations were made at levels of 0.14-14 microg lipid/injection. The intra- and inter-day precision values of the method ranged between 1.9 and 4.5 and 2.3-7.2% (RSD, n=6), respectively, including determinations at two concentration levels. In comparison to other lipid classes, quantitation of PC proved to be equally repeatable despite its lowest detector response. The relative recoveries varied from 97.0 to 110.3%, showing good accuracy of the method. The methodological variation of the lipid classes covered 0.6-3.1% of their total variation in the study population (n=48). The CE/FC ratio showed an even closer relationship with phospholipid linoleic acid (18:2n-6; r=0.65, P<0.001) than with serum cholesterol levels, while eicosapentaenoic acid (20:5n-3) was significantly associated with PC (r=0.41, P<0.01). The CE/FC ratio increased (P<0.01) during soyabean oil substitution and the level of PC increased (P<0.01) during cold-pressed rapeseed oil substitution.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Lípidos/sangre , Ácidos Grasos/análisis , Ácidos Grasos/química , Humanos , Lípidos/análisis , Lípidos/clasificación , Fosfolípidos/análisis , Fosfolípidos/química , Aceites de Plantas/química , Reproducibilidad de los Resultados
11.
Br J Pharmacol ; 130(5): 1147-55, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10882401

RESUMEN

1. The effect of ambient temperature on the nicotine-induced (0.3, 0.5 or 0.8 mg kg(-1) s.c.) changes of the striatal concentrations of dopamine (DA) and its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) was studied in freely-moving rats by in vivo microdialysis. 2. At the ambient temperature of 30 - 33 degrees C, but not at 20 - 23 degrees C, nicotine doses of 0.5 (P<0. 01) and 0.8 mg kg(-1) (P<0.05) significantly increased the extracellular DA concentration. The nicotine doses of 0.5 and 0.8 mg kg(-1) increased the DA metabolite levels similarly at both ambient temperatures studied (P

Asunto(s)
Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Nicotina/farmacología , Animales , Corticosterona/sangre , Masculino , Microdiálisis , Nicotina/farmacocinética , Ratas , Ratas Wistar , Receptores Nicotínicos/fisiología , Temperatura
12.
J Pediatr ; 136(1): 46-52, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10636973

RESUMEN

OBJECTIVE: We evaluated whether replacing a proportion of saturated fat with vegetable oils in the diet of young children increases trans fatty acid intake. STUDY DESIGN: Dietary counseling aimed to reach a dietary fat ratio of unsaturated to saturated fat of 2:1 within a total fat intake of 30% to 35% of energy (E%). Four-day food records of 813 3-year-old children were analyzed, and serum phospholipid fatty acid compositions of 25 randomly selected intervention children and 17 control children were analyzed. RESULTS: trans fatty acid intake of the intervention and control children was small (0.8 E% and 0.6 E%, respectively; P <.001). The relative content of serum phospholipid trans 18:1 was closely similar in intervention and control children (1.0% and 0.9% of all fatty acids, respectively). Trans fatty acid intake and serum trans 18:1 correlated poorly with children's serum cholesterol and HDL cholesterol concentrations and inversely with serum phospholipid arachidonic to linoleic acid ratio (r = -0.373). CONCLUSIONS: Trans fatty acid intake of children in Finland is minimal. Dietary intervention replacing saturated with unsaturated fatty acids is safe because it does not increase trans fatty acid intake or the relative content of trans fatty acids in the serum phospholipid fraction.


Asunto(s)
Colesterol en la Dieta/administración & dosificación , Dieta con Restricción de Grasas , Grasas Insaturadas en la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos/administración & dosificación , Fosfolípidos/sangre , Ácido Araquidónico/sangre , Arteriosclerosis/prevención & control , Preescolar , Colesterol/sangre , HDL-Colesterol/sangre , Consejo , Grasas Insaturadas en la Dieta/análisis , Ingestión de Energía , Ácidos Grasos/análisis , Ácidos Grasos Insaturados/análisis , Finlandia , Humanos , Isomerismo , Ácido Linoleico/sangre , Registros Médicos , Fosfolípidos/análisis , Aceites de Plantas/administración & dosificación , Estudios Prospectivos , Factores de Riesgo
13.
J Agric Food Chem ; 47(7): 2738-42, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10552556

RESUMEN

A combined derivatization method for gas chromatographic/mass spectrometric (GC/MS) analysis of steroidal glycoalkaloid (SGA) aglycons was developed using both trimethylsilylation and pentafluoropropionylation. In comparison with underivatized or only silylated aglycons, the new technique produces more specific and abundant fragmentation for compounds with a tomatidine-type structure. For example, the difference between solasodine and tomatidine, the former containing a double bond at position 5,6 in the steroidal skeleton, can be observed by their base peak fragments at m/z 417 (C(24)H(41)O(2)Si(2)) and m/z 419 (C(24)H(43)O(2)Si(2)). The method is well suited for the simultaneous determination of both solanidane- and spirosolane-type SGA aglycons from Solanum species and hybrids. The reproducibility of the method, including SGA extraction, hydrolysis, derivatization, and quantitative GC/MS analysis, was <6% (CV) for the principal aglycons determined from a hybrid between a wild potato species, Solanum brevidens Phil., and a cultivated potato, S. tuberosum L. A single ion monitoring technique using specific fragments m/z 419 and 417 could be applied for the determination of minor stereoisomers, which are often overlapped by large amounts of tomatidine.


Asunto(s)
Alcaloides Solanáceos/análisis , Tomatina/análogos & derivados , Diosgenina , Cromatografía de Gases y Espectrometría de Masas , Reproducibilidad de los Resultados , Tomatina/análisis
14.
J Int Med Res ; 26(4): 171-80, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9818783

RESUMEN

An extract from red-wine grape fermentation, ANOX has been developed as a source of red-wine polyphenols, which are thought to inhibit several of the pathogenic pathways that lead to cardiovascular disease. New data indicate that this extract has a significantly greater effect than either red wine or red-wine powder on the inhibition of platelet aggregation in vitro. Based on this data, about 300 - 500 mg of the extract is equivalent to the daily dose of red-wine polyphenols that appears to protect against cardiovascular disease. The possible synergistic effect of red-wine polyphenols with vitamin C, their vasorelaxing activity and their possible role in preventing over-crosslinking of connective tissues (premature ageing) are considered. The extract contains standardized amounts of the whole spectrum of polyphenolic compounds found in red wine and may provide a valuable reference substance in clinical investigations of the physiological actions of plant polyphenols; its potential use in functional nutrition and preventive medicine is also discussed.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Flavonoides , Fenoles/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Agregación Plaquetaria/efectos de los fármacos , Polímeros/uso terapéutico , Vino , Animales , Humanos , Polifenoles
15.
Br J Clin Pharmacol ; 43(1): 29-33, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9056049

RESUMEN

AIMS: The purpose of this study was to investigate the effect of activated charcoal on the absorption of amlodipine, with special reference to delayed charcoal administration. METHODS: Thirty-two healthy volunteers, eight subjects in four parallel groups, ingested 10 mg of amlodipine on an empty stomach. Activated charcoal (25 g in 300 ml of water) was ingested either immediately afterwards or 2 h or 6 h after amlodipine, or amlodipine was ingested with 300 ml of water only (control). Plasma concentrations and the cumulative excretion of amlodipine into urine were measured by GC-MS for 96 h and 72 h, respectively. In addition, adsorption of amlodipine to charcoal was studied in vitro. RESULTS: Activated charcoal administered immediately after amlodipine reduced the amlodipine AUC(0.96 h) and the 72-h urinary excretion by 99% (P < 0.0005). After a delay of 2 h in charcoal administration the AUC(0.96 h) was reduced by 49% (P = 0.001), but after a delay of 6 h the reduction was 15% only (P = NS). At a charcoal:drug ratio of 5:1, about 90% of amlodipine was adsorbed by charcoal in vitro; at ratios of 10:1 and 20:1, adsorption was practically complete. CONCLUSIONS: Activated charcoal almost completely prevented amlodipine absorption when administered immediately after amlodipine ingestion. Charcoal also markedly reduced amlodipine absorption when given 2 h after amlodipine; in amlodipine overdose, administration of charcoal may be beneficial even later. We conclude that administration of activated charcoal is the method of choice to prevent absorption of amlodipine in amlodipine overdose.


Asunto(s)
Amlodipino/farmacocinética , Bloqueadores de los Canales de Calcio/farmacocinética , Carbón Orgánico/administración & dosificación , Absorción Intestinal , Adsorción/efectos de los fármacos , Adulto , Amlodipino/efectos adversos , Análisis de Varianza , Bloqueadores de los Canales de Calcio/efectos adversos , Sobredosis de Droga/prevención & control , Femenino , Humanos , Masculino
16.
J Chromatogr B Biomed Appl ; 687(2): 371-8, 1996 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-9017460

RESUMEN

Octadecenoic (18:1) trans-fatty acid fractions from margarine, butter and plasma phospholipids (PL) were isolated by silver ion TLC, and nine positional isomers (n-11-n-3) were identified by GC-MS based on their ozonolysis products. The GC analysis of the isolated fractions gave similar peak profiles and separated seven trans-isomers (n-11-n-6 and n-3). Without a preceding isolation step, the reproducibility of the GC method for plasma PL elaidic (18:1 n 9 trans) and trans-vaccenic acids (n-7) was 3.4 and 2.7% (R.S.D.), respectively. These trans-isomers were rapidly incorporated and cleared in plasma PL and they closely reflected both increased and decreased intake of 18:1 trans-fatty acids during moderate fat substitutions. Significant associations between high-density lipoprotein cholesterol (HDL-C) and PL elaidic and trans-vaccenic acids appeared in habitual margarine users only.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Ácido Oléico/sangre , Ácidos Oléicos/sangre , Fosfolípidos/sangre , Adulto , Mantequilla , Cromatografía en Capa Delgada , Grasas de la Dieta/sangre , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Margarina , Aceite de Oliva , Fosfolípidos/química , Aceites de Plantas
17.
Naunyn Schmiedebergs Arch Pharmacol ; 353(1): 110-5, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8750924

RESUMEN

The effect of chronic oral administration of nicotine on the circadian rhythm of striatal dopamine (DA) and 5-hydroxytryptamine (5-HT) was studied in mice. Mice receiving nicotine in their drinking water and control mice drinking tap water were killed at 05:00, 11:00, 15:00 or 21:00 hours on the 50th day of chronic administration. The plasma concentrations of nicotine and cotinine, as well the striatal concentrations of DA, 5-HT and their metabolites 3,4 dihydroxyphenylacetic acid (DOPAC), 3-methoxytyramine (3-MT), homovanilic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were estimated. The largest plasma concentrations of nicotine and cotinine were found at 05:00, when they were more than double the concentrations found at the other times studied. This indicates that the mice, typically for nocturnal animals, consumed most of their daily drinking water at night. In the control mice, the striatal DA and 3-MT concentrations showed circadian variation and were lowest at 11:00. The 5-HIAA concentrations also varied, being highest at 11:00. In the nicotine-treated mice the circadian variations in striatal monoamines were altered and more pronounced than in the controls. The concentrations of DA, DOPAC, HVA and 5-HIAA were highest at 11:00 and that of 5-HT at 21:00. The striatal DA, DOPAC, HVA and 5-HIAA concentrations in the nicotine-treated mice were significantly higher at 11:00 and the 5-HT concentrations at 21:00 than in the control mice, and, in contrast to the control mice, in the mice treated with chronic nicotine no circadian rhythm was observed in the 3-MT. No elevation of striatal DA metabolites occurred in the nicotine-treated mice compared with the controls when the plasma nicotine concentration was at its peak at 05:00. This finding suggests development of tolerance to the nicotine-induced changes in striatal DA metabolism. Further, our findings suggest that the chronic administration of nicotine in the drinking water of mice alters the circadian pattern of striatal DA and, to a lesser extent, that of 5-HT, and thus may affect the functions regulated by these transmitters.


Asunto(s)
Ritmo Circadiano/efectos de los fármacos , Cuerpo Estriado/efectos de los fármacos , Dopamina/metabolismo , Nicotina/farmacología , Serotonina/metabolismo , Administración Oral , Animales , Cuerpo Estriado/metabolismo , Cotinina/sangre , Ingestión de Líquidos/efectos de los fármacos , Masculino , Ratones , Nicotina/sangre
18.
Ann Nutr Metab ; 37(4): 161-74, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8105749

RESUMEN

The effects of zero erucic acid rapeseed oil and olive oil on plasma fatty acid composition and serum cholesterol were studied in margarine users (n = 46). The replacement of margarine on bread by these oils accounted, on average, for 16% of the total fat and 7% of the total energy intake. Fatty acid analysis of total plasma indicated a dose-dependent rise in alpha-linolenic (alpha-LLA) and oleic acid (OA) levels during rapeseed and olive oil substitutions, respectively. Rapeseed oil substitution increased the proportion of eicosapentaenoic acid (0.4%- units, on average) in plasma phospholipids. A slight decrease in low-density lipoprotein cholesterol (LDL-C) and an increase in high-density lipoprotein cholesterol (HDL-C, 4.5%, p < 0.01) led to a significantly higher HDL-C/total cholesterol (TC) ratio (1.9%-units). The results suggest a marked competitive effect for alpha-LLA, not only among plasma phospholipid fatty acids, but also in the relationships with serum lipids, since the changes in alpha-LLA, rather than in OA, were associated with those in LDL-C and the HDL-C/TC ratio. No competitive action of polyunsaturated acids comparable to rapeseed oil was found during olive oil substitution. In contrast to the rapeseed oil diet, the reduced proportion of linoleic acid (LA) in plasma phospholipids was not restored; this may be unfavorable if the habitual intake of LA is low. However, the effects on LDL-C levels were beneficial: the concentration decreased by 5.9% (p < 0.01), correlating inversely with the increase in OA. In addition, the concentration of HDL-C remained unchanged during olive oil substitution.


Asunto(s)
Colesterol/sangre , Grasas Insaturadas en la Dieta/farmacología , Ácidos Grasos/sangre , Margarina , Aceites de Plantas/administración & dosificación , Adulto , Pan , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Grasas Insaturadas en la Dieta/administración & dosificación , Ácidos Grasos Monoinsaturados/administración & dosificación , Ácidos Grasos Monoinsaturados/sangre , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ácido Oléico , Ácidos Oléicos/sangre , Aceite de Oliva , Fosfolípidos/sangre , Aceite de Brassica napus , Ácido alfa-Linolénico/sangre
19.
Br J Nutr ; 68(3): 639-54, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1362891

RESUMEN

The effects of zero-erucic acid rapeseed oil and rapeseed oil-containing margarine on plasma fatty acid composition and serum cholesterol were studied in butter users (n 43). Compliance to the substitution was followed by fatty acid analysis of total plasma and plasma phospholipids. The amount of substitute fats represented, on average, 21% of total fat and 8% of total energy intake. Changes in the relative fatty acid composition of plasma phospholipids indicated further fatty acid metabolism, and were closely related to the serum cholesterol level. The reduction in saturated fatty acids led to a significant increase in the proportion of n-3 and n-6 polyunsaturated fatty acids (PUFA) with the rapeseed oil diet, whereas the margarine caused a significant rise in n-6 PUFA only. The increase in the proportions of the two PUFA families occurred in accordance with their competitive order, most completely with the rapeseed oil diet. When butter was replaced by rapeseed oil, low-density-lipoprotein-cholesterol decreased by an average of 9.1% without a reduction in high-density-lipoprotein-cholesterol. During margarine substitution the reduction was 5.2%, on average. Of the plasma phospholipids, alpha-linolenic acid and the linoleic:stearic acid ratio, but not oleic acid, were the components most significantly correlated with serum cholesterol levels or the decrease in these levels. The results show that rapeseed oil can act primarily as a source of essential fatty acids, rather than that of monoenes, in the diet of butter users.


Asunto(s)
Brassica , Colesterol/sangre , Ácidos Grasos/sangre , Aceites de Plantas/farmacología , Adulto , LDL-Colesterol/sangre , Ácidos Grasos Monoinsaturados , Humanos , Ácidos Linolénicos/sangre , Lípidos/sangre , Fosfolípidos/sangre , Aceites de Plantas/administración & dosificación , Aceite de Brassica napus , Ácido alfa-Linolénico
20.
Planta Med ; 57(4): 393-4, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17226174
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