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1.
Nutrients ; 13(10)2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34684511

RESUMEN

This study aimed to gain deeper knowledge about the relationship between vitamin D and physical activity in a sample of forensic inpatients. Sixty-seven male forensic inpatients participated. Participants were randomly assigned into an Intervention group (vitamin D) or a Control group (placebo). The Physical Activity-Rating (PA-R) questionnaire was used to measure physical activity from January to May. Vitamin D status was measured as 25-hydroxy vitamin D (25-OHD) pre- and post-intervention. The results revealed that vitamin D status at post-test was positively correlated with physical activity, but there was no effect of vitamin D supplementation looking at the two randomized groups. However, controlling for body mass index (BMI), the results showed an effect of BMI and a main effect of groups with a higher level of physical activity in the Intervention group. No interaction effects were found. Participants were also assigned into High and Low vitamin D groups based on the vitamin D status at post-test; i.e., the upper (75.1 nmol/L) and lower quartile (46.7 nmol/L). T-tests revealed that participants with a vitamin D status above 75 nmol/L showed significantly higher levels of physical activity than participants with a vitamin D status below 46.7 nmol/L. Thus, a vitamin D status above 75 nmol/L seems to be an optimal level.


Asunto(s)
Suplementos Dietéticos , Ejercicio Físico/fisiología , Estado Nutricional/efectos de los fármacos , Vitamina D/análogos & derivados , Vitamina D/administración & dosificación , Vitaminas/administración & dosificación , Adulto , Índice de Masa Corporal , Método Doble Ciego , Humanos , Pacientes Internos , Masculino , Persona de Mediana Edad , Prisioneros , Estaciones del Año , Resultado del Tratamiento , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/terapia
2.
Nutrients ; 12(11)2020 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-33114392

RESUMEN

Vitamin D status may be important for stress resilience. This study investigated the effects of vitamin D supplements during winter on biological markers of stress resilience such as psychophysiological activity, serotonin, and cortisol in a placebo-controlled, randomized clinical trial. Eighty-six participants were randomly assigned to the Intervention (vitamin D) or Control (placebo) groups. Before and after the intervention participants were exposed to an experimental stress procedure. Psychophysiological activity was measured during three main conditions: baseline, stress, and recovery. Fasting blood samples were taken in the morning and saliva samples were collected at seven different time points across 24 h. Prior to intervention both groups had normal/sufficient vitamin D levels. Both groups showed a normal pattern of psychophysiological responses to the experimental stress procedure (i.e., increased psychophysiological responses from resting baseline to stress-condition, and decreased psychophysiological responses from stress-condition to recovery; all p < 0.009). Post-intervention, the Intervention group showed increased vitamin D levels (p < 0.001) and normal psychophysiological responses to the experimental stress procedure (p < 0.001). Importantly, the Control group demonstrated a classic nadir in vitamin D status post-intervention (spring) (p < 0.001) and did not show normal psychophysiological responses. Thus, physiologically the Control group showed a sustained stress response. No significant effects of vitamin D were found on serotonin and cortisol.


Asunto(s)
Suplementos Dietéticos , Resiliencia Psicológica/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos , Vitamina D/administración & dosificación , Vitaminas/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Método Doble Ciego , Ayuno/sangre , Femenino , Humanos , Hidrocortisona/metabolismo , Masculino , Persona de Mediana Edad , Estado Nutricional , Saliva/química , Estaciones del Año , Serotonina/sangre , Vitamina D/análogos & derivados , Vitamina D/sangre
3.
Food Nutr Res ; 642020.
Artículo en Inglés | MEDLINE | ID: mdl-32180692

RESUMEN

BACKGROUND: Fish consumption has been shown to have beneficial effects on biological and subjective measures of health and well-being. However, little is known about the effects of fish consumption at the behavioral level. OBJECTIVE: The primary aim of this study was to investigate the influence of diet on behavior such as physical activity during winter in forensic inpatients. The secondary aim was to investigate the relationship between vitamin D status and physical activity. DESIGN: Eighty-one male forensic inpatients participated in this study. Participants were randomized into two different diet groups: a Fish group receiving fatty fish three times per week and a Control group receiving an alternative meal (e.g. chicken, pork, and beef); while the Fish group received their fish, the Control group received an alternate meal, but with the same nutritional value as their habitual diet. The duration of the food intervention was 6 months. RESULTS: The results revealed that the Fish group had a regular pattern of physical activity throughout the intervention period. The participants in the Control group showed a more irregular pattern of physical activity in addition to a significant reduction in physical activity over time. CONCLUSION: Behavior such as physical activity during winter seemed to be influenced by the diet.

4.
Int J Food Sci Nutr ; 70(7): 813-824, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30969141

RESUMEN

Eight different Serbian genotypes were analysed for their polyphenol, carotenoid, vitamin C content and evaluated for their antioxidant properties. The highest content of biologically important carotenoids such as lutein (4.58 mg/10 g), lycopene (160.64 mg/10 g) and ß-carotene (189.64 mg/10 g) were detected in the genotype S606. Rutin was the most abundant phenolic compound in all tastes samples, but its content is highest in the genotype S615 (1424.30 µg/100 g dw). All tomato samples were the great source of vitamin C, where the sample S615 stood out (68.54 mg AA g-1 of dw). Their content of antioxidant compounds suggested that genotypes S606 and S615 showed the best antioxidant potential. Principal component analysis (PCA) and Partial least squares (PLS) were applied to analyse results. The results obtained in the present study could be of considerable interest for breeding programmes wishing to select tomato genotypes with high biological and nutritional properties.


Asunto(s)
Antioxidantes/análisis , Frutas/química , Valor Nutritivo , Fitoquímicos/análisis , Solanum lycopersicum/química , Ácido Ascórbico/análisis , Carotenoides/análisis , Análisis de los Alimentos , Genotipo , Licopeno/análisis , Solanum lycopersicum/clasificación , Polifenoles/análisis , Espectrometría de Masas en Tándem , Gusto , beta Caroteno/análisis
5.
Scand J Psychol ; 58(2): 123-130, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28252190

RESUMEN

The aim of the present randomized double-blind placebo control trial was to investigate if vitamin D supplementation had an effect on vitamin D status, executive functioning and self-perceived mental health in a group of Norwegian adolescents during winter time. Fifty adolescents were randomly assigned into an intervention group (vitamin D pearls) or a control group (placebo pearls). Before (pre-test in December/January) and after (post-test in April/May) the intervention period the participants were exposed to a test procedure, consisting of blood draw, completion of cognitive tests (Tower of Hanoi and Tower of London), and the Youth Self-report version of the Child Behavior Checklist. Multivariate data analysis showed that participants with low vitamin D status scored worse on the Tower of London tests and the more difficult sub-tasks on the Tower of Hanoi tests. They also had a tendency to report higher frequency of externalizing behavior problems and attention deficit. At pre-test, the overall mean vitamin D status measured as 25-hydroxy vitamin D was 42 nmol/L, defining deficiency (Intervention group = 44 nmol/L, Control group = 39 nmol/L). However, vitamin D supplementation caused a significant increase in vitamin D status resulting in a sufficient level in the Intervention group at post-test (mean 62 nmol/L). The results also revealed that the intervention group improved their performance on the most demanding sub-tasks on the ToH. Overall, the study indicates that vitamin D status in adolescents may be important for both executive functioning and mental health.


Asunto(s)
Función Ejecutiva , Conocimientos, Actitudes y Práctica en Salud , Salud Mental , Vitamina D/administración & dosificación , Adolescente , Método Doble Ciego , Femenino , Humanos , Masculino , Análisis Multivariante , Noruega , Pruebas Psicológicas , Estaciones del Año , Vitamina D/sangre , Deficiencia de Vitamina D/psicología
6.
Lipids ; 51(1): 61-73, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26552397

RESUMEN

The membrane phospholipid composition in mammalian brain can be modified either by nutrients such as dietary fatty acids, or by certain toxic substances such as methylmercury (MeHg), leading to various biological and toxic effects. The present study evaluated the effects of eicosapentaenoic acid (EPA) and MeHg on the composition of the two most abundant membrane phospholipid classes, i.e., phosphatidylcholines (PtdCho) and phosphatidylethanolamines (PtdEtn), in mouse brain by using a two-level factorial design. The intact membrane PtdCho and PtdEtn species were analyzed by liquid chromatography-mass spectrometry. The effects of EPA and MeHg on the PtdCho and PtdEtn composition were evaluated by principal component analysis and ANOVA. The results showed that EPA and MeHg had different effects on the composition of membrane PtdCho and PtdEtn species in brain, where EPA showed strongest impact. EPA led to large reductions in the levels of arachidonic acid (ARA)-containing PtdCho and PtdEtn species in brain, while MeHg tended to elevate the levels of ARA-containing PtdCho and PtdEtn species. EPA also significantly increased the levels of PtdCho and PtdEtn species with n-3 fatty acids. Our results indicate that EPA may to some degree counteract the alterations of the PtdCho and PtdEtn pattern induced by MeHg, and thus alleviate the MeHg neurotoxicity in mouse brain through the inhibition of ARA-derived pro-inflammatory factors. These results may assist in the understanding of the interaction between MeHg, EPA and phospholipids, as well as the risk and benefits of a fish diet.


Asunto(s)
Ácido Araquidónico/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Ácido Eicosapentaenoico/farmacología , Compuestos de Metilmercurio/farmacología , Fosfolípidos/química , Fosfolípidos/metabolismo , Animales , Suplementos Dietéticos , Ácido Eicosapentaenoico/administración & dosificación , Ácido Eicosapentaenoico/química , Masculino , Compuestos de Metilmercurio/administración & dosificación , Compuestos de Metilmercurio/química , Ratones , Ratones Endogámicos C57BL
7.
Scand J Psychol ; 56(5): 467-74, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26032440

RESUMEN

The aim of the present study was to investigate the effects of fatty fish consumption on cognitive functioning in a group of inpatients characterized by antisocial behavior. Eighty-three male forensic inpatients participated in this study. Participants were randomly assigned into a Fish or a Control group (e.g., meat, chicken, pork). One decision-making task, the Iowa Gambling Task (IGT), and one planning task, the Tower of Hanoi (ToH), were administered before (pre-test) and at the end of the intervention period (post-test). For the IGT the Fish group showed improved performance from pre- to post- test. Moreover, the Fish group showed significantly better performance than the Control group on the IGT at post-test. The Fish group also demonstrated improved performance from pre- to post-test on the ToH; however, this was limited to participants with a history of substance abuse. Further, the improvement was only significant for tasks with high working memory load (5-7 move problems), and not for tasks with low working memory load (1-4 move problems). The Control group showed no improvement on any of the tasks regardless of alcohol or drug abuse history. The present study suggests that regular fatty fish consumption may improve executive functions in forensic inpatients with antisocial traits and a history of substance abuse. Thus, the current results may have important implications with regard to health care interventions.


Asunto(s)
Trastorno de Personalidad Antisocial/dietoterapia , Función Ejecutiva , Evaluación de Resultado en la Atención de Salud , Salmo salar , Alimentos Marinos , Trastornos Relacionados con Sustancias/dietoterapia , Adulto , Animales , Criminales , Humanos , Masculino , Persona de Mediana Edad , Delitos Sexuales , Adulto Joven
8.
Front Psychol ; 6: 135, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25741303

RESUMEN

The overall aim of the present study was to explore the relationship between medicinal use and fatty fish consumption on heart rate variability (HRV) and heart rate (HR) in a group of forensic inpatients on a variety of medications. A total of 49 forensic inpatients, randomly assigned to a fish group (n = 27) or a control group (n = 22) were included in the present study. Before and by the end of the food intervention period HR and HRV were measured during an experimental test procedure. An additional aim of this paper is to show how multivariate data analysis can highlight differences and similarities between the groups, thus being a valuable addition to traditional statistical hypothesis testing. The results indicate that fish consumption may have a positive effect on both HR and HRV regardless of medication, but that the influence of medication is strong enough to mask the true effect of fish consumption. Without correcting for medication, the fish group and control group become indistinguishable (p = 0.0794, Cohen's d = 0.60). The effect of medication is demonstrated by establishing a multivariate regression model that estimates HR and HRV in a recovery phase based on HR and HRV data recorded during psychological tests. The model performance is excellent for HR data, but yields poor results for HRV when employed on participants undergoing the more severe medical treatments. This indicates that the HRV behavior of this group is very different from that of the participants on no or lower level of medication. When focusing on the participants on a constant medication regime, a substantial improvement in HRV and HR for the fish group compared to the control group is indicated by a principal component analysis and t-tests (p = 0.00029, Cohen's d = 2.72). In a group of psychiatric inpatients characterized by severe mental health problems consuming different kinds of medication, the fish diet improved HR and HRV, indices of both emotional regulation and physical health.

9.
Nutrients ; 6(12): 5405-18, 2014 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-25431880

RESUMEN

The aim of the present study was to investigate the effects of Atlantic salmon consumption on underlying biological mechanisms associated with anxiety such as heart rate variability (HRV) and heart rate (HR) as well as a measure of self-reported anxiety. Moreover, these biological and self-reported outcome measures were investigated in relation to specific nutrients; vitamin D status, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Ninety-five male forensic inpatients were randomly assigned into a Fish (Atlantic salmon three times per week from September to February) or a Control group (alternative meal, e.g., chicken, pork, or beef three times per week during the same period). HRV measured as the root mean square of successive differences (rMSSD), HR, state- and trait-anxiety (STAI), were assessed before (pre-test) and at the end of the 23 weeks dietary intervention period (post-test). The Fish group showed significant improvements in both rMSSD and HR. The Fish group also showed significant decreases in state-anxiety. Finally, there was a positive relationship between rMSSD and vitamin D status. The findings suggest that Atlantic salmon consumption may have an impact on mental health related variables such as underlying mechanisms playing a key role in emotion-regulation and state-anxiety.


Asunto(s)
Ansiedad/dietoterapia , Pacientes Internos/psicología , Salmo salar , Alimentos Marinos , Adulto , Animales , Ansiedad/sangre , Ansiedad/diagnóstico , Ansiedad/fisiopatología , Ansiedad/psicología , Biomarcadores/sangre , Criminales , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Evaluación Nutricional , Estado Nutricional , Escalas de Valoración Psiquiátrica , Inducción de Remisión , Delitos Sexuales , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos , Vitamina D/sangre , Adulto Joven
10.
Appl Spectrosc ; 68(10): 1190-200, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25198190

RESUMEN

The potential of Fourier transform infrared (FT-IR), near-infrared (NIR), and Raman spectroscopic techniques combined with partial least squares (PLS) regression (PLSR) to predict concentrations of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and total omega-3 fatty acids (n-3 FAs) in fish oil supplements was investigated. FT-IR spectroscopy predicted EPA (coefficient of determination (R(2)) of 0.994, standard error of cross-validation (SECV) of 2.90%, and standard error of prediction (SEP) of 2.49%) and DHA (R(2) = 0.983, SECV = 2.89%, and SEP = 2.55%) with six to seven PLS factors, whereas a simpler PLS model with two factors was obtained for total n-3 FAs (R(2) = 0.985, SECV = 2.73%, and SEP = 2.75%). Selected regions in the NIR spectra gave models with good performances and predicted EPA (R(2) = 0.979, SECV = 2.43%, and SEP = 3.11%) and DHA (R(2) = 0.972, SECV = 2.34%, and SEP = 2.60%) with four to six PLS factors. Both the whole and selected NIR regions gave simple models (two PLS factors) with similar results (R(2) = 0.997, SECV = 2.18%, and SEP = 1.60%) for total n-3 FAs. The whole and selected regions of Raman spectra provided models with comparable results and predicted EPA (R(2) = 0.977, SECV = 3.18%, and SEP = 2.73%) and DHA (R(2) = 0.966, SECV = 3.31%, and SEP = 2.56%) with seven to eight PLS factors, whereas a simpler model (three PLS factors) with R(2) = 0.993, SECV = 2.82%, and SEP = 3.27% was obtained for total n-3 FAs. The results demonstrated that FT-IR, NIR, and Raman spectroscopy combined with PLSR can be used as simple, fast, and nondestructive methods for quantitative analysis of EPA, DHA, and total n-3 FAs. FT-IR and NIR spectroscopy, in particular, have the potential to be applied in process industries during production of fish oil supplements.


Asunto(s)
Suplementos Dietéticos/análisis , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-3/química , Aceites de Pescado/química , Análisis Espectral/métodos , Análisis de los Mínimos Cuadrados , Vibración
11.
J Chromatogr A ; 1353: 57-64, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24238707

RESUMEN

A simple method coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated for the extraction of prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) from human plasma. The extraction protocol consisted of adding formic acid (10 µL) and acetonitrile (140 µL) to human plasma (50 µL) and further injection of the supernatant (25 µL) into the LC-MS/MS. The method was selective for PGE2 and LTB4 and the regression models, based on deuterated internal standards (30 ng mL(-1) PGE2-d4 and 40 ng mL(-1) LTB4-d4), were linear over the concentration range 1.0-50.0 ng mL(-1) with limits of detection (3 × σblank) and quantification (6 × σblank) of 0.5 ng mL(-1) and 1 ng mL(-1) for both eicosanoids. The recovery ranges were 95.1-104.7% for PGE2 and 86.4-103.2% for LTB4. The developed method was successfully implemented on plasma samples from patients before and after exposure to certain anti-inflammatory treatment.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Dinoprostona/sangre , Leucotrieno B4/sangre , Espectrometría de Masas en Tándem/métodos , Humanos , Límite de Detección , Solventes/química
12.
Artículo en Inglés | MEDLINE | ID: mdl-23168239

RESUMEN

Applying gas chromatography-mass spectrometry of 4,4-dimethyloxazoline fatty acid derivatives, the fatty acid composition of 15 mushroom species belonging to 9 genera and 5 families of order Agaricales growing in Bulgaria is determined. The structure of 31 fatty acids (not all present in each species) is unambiguously elucidated, with linoleic, oleic and palmitic acids being the main components (ranging between 70.9% (Marasmius oreades) and 91.2% (Endoptychum agaricoides)). A group of three hexadecenoic positionally isomeric fatty acids, 6-, 9- and 11-16:1, appeared to be characteristic components of the examined species. By applying chemometrics it was possible to show that the fatty acid composition closely reflects the classification of the species.


Asunto(s)
Agaricales/química , Agaricales/clasificación , Ácidos Grasos/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Agaricales/aislamiento & purificación
13.
J Chromatogr A ; 1218(38): 6823-31, 2011 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-21851946

RESUMEN

The retention behavior of components analyzed by chromatography varies with instrumental settings. Being able to predict how changes in these settings alter the elution pattern is useful, both with regards to component identification, as well as with regards to optimization of the chromatographic system. In this work, it is shown how experimental designs can be used for this purpose. Different experimental designs for response surface modeling of the separation of fatty acid methyl esters (FAME) as function of chromatographic conditions in GC have been evaluated. Full factorial, central composite, Doehlert and Box-Behnken designs were applied. A mixture of 38 FAMEs was separated on a polar cyanopropyl substituted polysilphenylene-siloxane phase capillary column. The temperature gradient, the start temperature of the gradient, and the carrier gas velocity were varied in the experiments. The modeled responses, as functions of chromatographic conditions, were retention time, retention indices, peak widths, separation efficiency and resolution between selected peak pairs. The designs that allowed inclusion of quadratic terms among the predictors performed significantly better than factorial design. Box-Behnken design provided the best results for prediction of retention, but the differences between the central composite, Doehlert and Box-Behnken designs were small. Retention indices could be modeled with much better accuracy than retention times. However, because the errors of predicted tR of closely eluting peaks were highly correlated, models of resolution (Rs) that were based on retention time had errors in the same range as corresponding models based on ECL.


Asunto(s)
Ésteres/análisis , Ésteres/aislamiento & purificación , Ácidos Grasos/análisis , Ácidos Grasos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas/métodos , Modelos Teóricos , Proyectos de Investigación
14.
Analyst ; 136(7): 1507-14, 2011 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-21327272

RESUMEN

Assessing the capabilities of instrumental techniques aiming at differentiating marine oils is a matter of great importance for both authorities and industries which has been highlighted over 120 years. In this study, different strategies were evaluated by means of principal component analysis (PCA) for their performance in differentiating various marine oils. Triacylglycerols (TAGs) composition and four different profiles including total ion current (TIC) and total mass spectral (TMS) profiles derived from liquid chromatography electrospray single and tandem mass spectrometry (LC-ESI-MS and LC-ESI-MS(2)) were used as the dataset for PCA study. Among these strategies, the tandem TMS profiles from LC-ESI-MS(2) experiments as the dataset demonstrated to be the most rapid and convenient approach for the differentiation of various marine and plant oils investigated and for the representation of the characteristics TAG patterns. This novel approach represents an alternative and promising tool for fingerprinting and differentiating marine oils.


Asunto(s)
Organismos Acuáticos/química , Cromatografía Líquida de Alta Presión/métodos , Aceites/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Algoritmos , Análisis de Componente Principal
15.
Lipids ; 45(12): 1147-58, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20963508

RESUMEN

Exploring the capabilities of instrumental techniques for discriminating n-3 rich oils derived from animals is a very important though much neglected area that was emphasized more than 100 years ago. In this study the potential of gas chromatography (GC) for discriminating full fatty acid methyl ester (FAME) profiles from fish (cod liver and salmon) and marine mammal (seal and whale) oils is evaluated by means of principal component analysis (PCA). The FAME profiles from plant oils such as rapeseed, linseed and soy oils and seven different brands of n-3 supplements are also used in the discrimination process. The results from the PCA plots can reliably distinguish between plant, n-3 supplements, fish and marine mammal oils. By removing the contribution of the n-3 supplements and plant oils it is possible to discriminate between types of fish and marine animal oils. GC offers a rapid, simple and convenient means of discriminating oils from different species, brands and grades.


Asunto(s)
Cromatografía de Gases/métodos , Ácidos Grasos Omega-3/análisis , Aceites de Pescado/química , Animales , Grasas Insaturadas en la Dieta/análisis , Suplementos Dietéticos , Peces , Salmón
16.
Talanta ; 82(4): 1261-70, 2010 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20801327

RESUMEN

Though liquid chromatography electrospray tandem mass spectrometry (LC-ESI-MS(2)) has been widely used in the structural elucidation of triacylglycerols (TAG) in vegetable oils, its potentiality for the identification of TAG molecules in omega-3 rich oils remains unexplored till date. Hence, this article investigates the applicability of LC-ESI-MS(2) for the structural characterization of naturally occurring TAG in cod liver oil without the TAG fractionation during the sample preparation. A computational algorithm was developed to automatically interpret the mass spectra and elucidate the TAG structures respectively. The results were compared against the lipase benchmark method. A principal component analysis study revealed that it is possible to discriminate genuine from adulterated cod liver oil.


Asunto(s)
Cromatografía Liquida/métodos , Aceite de Hígado de Bacalao/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Triglicéridos/análisis
17.
Anal Chim Acta ; 640(1-2): 33-9, 2009 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-19362616

RESUMEN

Multivariate deconvolution methods applied for resolution of overlapping chromatographic peaks require bilinearity. This implies that the shape of the spectrum of each analyte should not change during the elution of a compound. However, in chromatography, the concentration of a compound in the detector changes rapidly. For scanning instruments, like most mass spectrometers where the ions within a scan are not recorded simultaneously, these concentration differences introduce significant differences between spectra on the left and right side of the chromatographic peak. Because of this scan-effect, the assumption of bilinearity is not valid. Several methods, all having their limitations, have previously been applied to reduce this effect. In this paper a methodology for reduction of the scan-effect by a rank annihilation approach is described, and applications on both simulated and experimental data are shown. The rank annihilation approach is more efficient and has a broader range of applications than previously described methods.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Artefactos , Análisis Factorial , Sensibilidad y Especificidad , Estereoisomerismo
18.
Anal Chem ; 77(17): 5635-42, 2005 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16131076

RESUMEN

In metabolomics, the objective is to identify differences in metabolite profiles between samples. A widely used tool in metabolomics investigations is gas chromatography-mass spectrometry (GC/MS). More than 400 compounds can be detected in a single analysis, if overlapping GC/MS peaks are deconvoluted. However, the deconvolution process is time-consuming and difficult to automate, and additional processing is needed in order to compare samples. Therefore, there is a need to improve and automate the data processing strategy for data generated in GC/MS-based metabolomics; if not, the processing step will be a major bottleneck for high-throughput analyses. Here we describe a new semiautomated strategy using a hierarchical multivariate curve resolution approach that processes all samples simultaneously. The presented strategy generates (after appropriate treatment, e.g., multivariate analysis) tables of all the detected metabolites that differ in relative concentrations between samples. The processing of 70 samples took similar time to that of the GC/TOFMS analyses of the samples. The strategy has been validated using two different sets of samples: a complex mixture of standard compounds and Arabidopsis samples.


Asunto(s)
Arabidopsis/metabolismo , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Cromatografía de Gases y Espectrometría de Masas/métodos , Redes y Vías Metabólicas , Arabidopsis/química , Arabidopsis/genética , Giberelinas/química , Mutación/genética
19.
Anal Bioanal Chem ; 380(3): 453-66, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15340770

RESUMEN

A method for assigning environmental variables to observed biological changes in benthic communities is proposed. The approach requires biological and environmental sampling at the same sites. Additionally, a biological gradient or trend such as a change in observed species or a significant change in their relative abundances is necessary in order to connect the biological observations to the environmental measurements. Whether there is a statistical significant correspondence between the environmental measurements and the biological changes is tested after quantifying the biological changes by using the community disturbance index (CDI). Finally, the environmental variables that are most strongly associated with the biological changes are identified, and it is proposed that these are strong candidates as the pollutants responsible for the biological changes observed. However, this cannot be confirmed using the monitored data only. The approach is tested on data collected in monitoring surveys at the Ekofisk oil field in the North Sea. The results indicate the method is feasible for assigning environmental variables to observed biological changes.


Asunto(s)
Ecosistema , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Sedimentos Geológicos/química , Análisis de los Mínimos Cuadrados , Mar del Norte , Petróleo , Factores de Tiempo
20.
Environ Toxicol Pharmacol ; 18(2): 127-33, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21782741

RESUMEN

The present paper describes a strategy for toxicological evaluation of complex mixtures based on chemical "fingerprinting" followed by pattern recognition (multivariate data analysis). The purpose is to correlate chemical fingerprints to measured toxicological endpoints, identify all major contributors to toxicity, and predict toxicity of additional mixtures. The strategy is illustrated with organic extracts of exhaust particles which are characterized by full scan gas chromatography-mass spectrometry (GC-MS). The complex GC-MS data are resolved into peaks and spectra for individual compounds using an automated curve resolution procedure. Projections to latent structures (PLS) is used for the regression modeling to correlate the GC-MS data to the measured responses; mutagenicity in the Ames Salmonella assay. The regression model identifies those peaks that co-vary with the observed mutagenicity. These peaks may be identified chemically from their spectra. Furthermore, the regression model can be used to predict mutagenicity from GC-MS chromatograms of additional samples.

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