Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Biomed Chromatogr ; 29(7): 1035-41, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25425119

RESUMO

In recent years it has been confirmed that the consumption of olive oil prevents the oxidation of biomolecules owing to its monounsaturated fatty acids (MUFA) and phenolic content. The main objective of the study was to develop an ultra-high-performance liquid chromatography (UHPLC) tandem mass spectrometry (MS/MS) method for the determination of phenolic compounds in human high-density lipoprotein (HDL) samples. At the same time, the influence of olive oil consumption on the phenolic metabolite levels was evaluated in a European population. The participants were 51 healthy men, aged 20-60. They were randomized to two consecutive intervention periods with the administration of raw olive oil with low and high polyphenolic content. The UHPLC-MS/MS analytical method has been validated for hydroxytyrosol and homovanillic acid in terms of linearity (r(2) = 0.99 and 1.00), repeatability (5.7 and 6.5%) reproducibility (6.2 and 7%), recovery (98 to 97%), limits of detection (1.7 to 1.8 ppb) and quantification (5.8 and 6.3 ppb).The levels of the studied metabolites increased significantly after high polyphenolic content virgin olive oil ingestion (p <0.05) compared with lowpolyphenolic content olive oil. Virgin olive oil consumption increases the levels of phenolic metabolites in HDL and thus provides human HDL with more efficient antioxidant protection.


Assuntos
Lipoproteínas HDL/sangue , Lipoproteínas HDL/química , Azeite de Oliva/química , Fenóis/análise , Adulto , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , Adulto Jovem
2.
Eur J Clin Nutr ; 67(6): 658-63, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23549201

RESUMO

BACKGROUND/OBJECTIVES: Fatty-acid status during in-utero development might influence the risk of atopic diseases in early childhood. The aim of this work was to identify the relationship between maternal plasma and cord blood fatty acid (FA) composition and the risk of atopic eczema in the offspring at 14 months of age. SUBJECTS/METHODS: Two hundred and eleven non-atopic mothers and their children were studied. Mothers were recruited in their first trimester of gestation and children were monitored until 14 months of age. Samples of maternal plasma and cord blood plasma were analyzed to determine the FA profile of total lipids. Presence of atopic eczema in the infants was documented through questionnaires at 6 and 14 months of age. RESULTS: Higher concentrations of total long-chain polyunsaturated FA (LC-PUFA) were found in maternal plasma of non-atopic children in relation to atopic group. Moreover, this maternal plasma LC-PUFA content was negatively correlated with the atopic eczema (odds ratios (OR)=0.83, P=0.04) in infants. Regarding cord blood samples, docosahexaenoic acid (DHA C22:6n3) and the sum of total n-3 and of LC-PUFA n-3 showed a negative correlation with the prevalence of the disease (OR=0.50, 0.49 and 0.49, respectively). CONCLUSIONS: Our results show that the fatty-acid status of the fetus during pregnancy has an important role in the development of atopic eczema in early childhood. The prevalence of this atopic disorder is related to lower cord blood plasma levels of FA belonging to n-3 series, especially DHA.


Assuntos
Desenvolvimento Infantil , Dermatite Atópica/etiologia , Dieta/efeitos adversos , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Insaturados/deficiência , Fenômenos Fisiológicos da Nutrição Materna , Estado Nutricional , Adulto , Estudos de Coortes , Dermatite Atópica/sangue , Dermatite Atópica/epidemiologia , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/sangue , Ácidos Docosa-Hexaenoicos/deficiência , Ácidos Graxos/sangue , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Insaturados/administração & dosagem , Ácidos Graxos Insaturados/sangue , Feminino , Sangue Fetal/metabolismo , Humanos , Recém-Nascido , Masculino , Gravidez , Prevalência , Risco , Espanha/epidemiologia
3.
Cardiol Young ; 20(4): 410-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20416135

RESUMO

BACKGROUND: The main cause of long-term morbidity and mortality after the arterial switch operation for transposition of great arteries is complication at the coronary arteries. Myocardial perfusion magnetic resonance imaging represents a relatively novel and appealing tool for detecting myocardial ischaemia but with little experience in paediatric patients. The purpose of this paper is to report a single centre experience with myocardial perfusion magnetic resonance imaging for detecting ischaemia after the arterial switch operation for transposition of great arteries. METHODS: Twenty-eight patients aged 13-16 years with an arterial switch operation for transposition of great arteries were included in the study. Coronary pattern, operative and postoperative complications, and long-term follow-up events were reviewed. Patient functional evaluation included clinical examination, electrocardiogram and echocardiogram. Every patient underwent magnetic resonance imaging perfusion scanning at rest and under adenosine-induced stress. RESULTS: All patients were symptom free with no ischaemic signs on the electrocardiogram. All magnetic resonance imaging examinations were generally well tolerated with minor adenosine secondary effects in 36% of the patients. Two stress myocardial perfusion magnetic resonance studies were excluded from analysis for technical reasons. No perfusion stress defects were detected at the remaining 26. Myocardial delayed enhancement was performed in all 28 patients. In five subjects, a subendocardial late enhancement consistent with patch tissue for septal defect closure at the time of repair was indentified. CONCLUSION: Magnetic resonance imaging evaluation of myocardial perfusion and viability is feasible in paediatric patients long after arterial switch operation. No signs of myocardial ischaemia or necrosis were documented in this young asymptomatic population. Further studies including coronary angiography correlation are needed to validate magnetic resonance imaging results.


Assuntos
Angiografia por Ressonância Magnética , Isquemia Miocárdica/diagnóstico , Transposição dos Grandes Vasos/cirurgia , Adolescente , Estudos de Coortes , Estudos de Viabilidade , Feminino , Humanos , Masculino , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/fisiopatologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Volume Sistólico , Fatores de Tempo , Transposição dos Grandes Vasos/complicações , Transposição dos Grandes Vasos/diagnóstico , Resultado do Tratamento
4.
J Chromatogr A ; 1157(1-2): 422-9, 2007 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-17532324

RESUMO

A new method for the determination of the main isomers of conjugated linoleic acid (CLA) in human and animal plasma was developed by gas chromatography coupled to flame ionization detection (GC-FID). The new method introduces three main advantages in comparison to the current available methodologies: firstly it does not require previous lipid extraction, secondly the chromatographic separation of CLA isomers was performed on an Rtx-2330 column significantly shorter and thinner than the typical long highly polar capillary columns in use that allows a faster analysis than in current methodologies, and thirdly the amount of sample needed to perform the analyses was substantially lower than the amount used in current routine methodologies. Its application to human plasma and rat plasma showed to be robust and reliable for quick and correct identification of the main CLA isomers in particular, and the total fatty acid profile in general, in routine analysis.


Assuntos
Cromatografia Gasosa/métodos , Ácido Linoleico/sangue , Animais , Humanos , Ratos
5.
Eur J Clin Nutr ; 61(12): 1345-51, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17299472

RESUMO

OBJECTIVE: To analyze compliance with the current European and Spanish nutritional objectives in a representative sample from Catalonia, a Spanish Mediterranean region; and to examine relationships between diet and plasma fatty acid composition. DESIGN: Cross-sectional nutritional survey. SETTING: Population based random sample derived from the Catalan Nutrition Survey. SUBJECTS: A total of 516 healthy adult men (n=203) and women (n=313). METHODS: Dietary habits were assessed by means of a quantitative food frequency questionnaire. A physical exam included height, weight, waist and hip circumferences, and a fasting blood draw. RESULTS: Gender differences were observed in nutrient and energy intakes. Women showed a better compliance with the nutritional recommendations for monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) than did men. Men showed a better compliance for saturated fatty acid (SFA) and carbohydrate than did women. However, the SFA:MUFA:PUFA ratio was similar in both gender (1.6:2.3:1.0 for men; 1.7:2.5:1.0 for women). The highest compliance was observed for nutritional goals of sodium, calcium and fruit and vegetable intakes for both genders. In addition, the present study showed that levels of certain fatty acids in plasma are clearly associated with dietary intake of foods rich in these components. The highest correlations were found for n-3 long chain polyunsaturated fatty acids with blue fish intake in both men and women (r (men)=0.36 and r (women)=0.42; P<0.001). CONCLUSIONS: The diet followed in Catalonia seems to ensure compliance with most of the intermediate nutritional objectives for the Spanish population. However, a reduction in the SFA intake and an increase in the carbohydrate intake could be recommended in order to reduce the current prevalence of overweight and obesity in this Mediterranean region. SPONSORSHIP: This study was supported by the Catalan Department of Health, the Nutrition Catalan Centre of the Institute of Catalan Studies, and Mercadona SA.


Assuntos
Dieta Mediterrânea , Gorduras Insaturadas na Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Política Nutricional , Obesidade/epidemiologia , Estatura , Peso Corporal , Cálcio da Dieta/administração & dosagem , Estudos Transversais , Carboidratos da Dieta/administração & dosagem , Ingestão de Energia/fisiologia , Feminino , Frutas , Humanos , Masculino , Inquéritos Nutricionais , Obesidade/prevenção & controle , Sobrepeso/epidemiologia , Sobrepeso/prevenção & controle , Distribuição por Sexo , Cloreto de Sódio na Dieta/administração & dosagem , Espanha/epidemiologia , Inquéritos e Questionários , Verduras , Relação Cintura-Quadril
6.
J Chromatogr A ; 1114(1): 132-7, 2006 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-16574129

RESUMO

A rapid direct method (Method I) for measuring gamma- and alpha-tocopherols in human milk was developed and validated using reversed-phase high-performance liquid chromatography with ultraviolet/visible (UV-vis) detection. Human milk, with an internal standard (alpha-tocopherol acetate) added, was diluted in hexane. The chromatographic system consisted of a short column (50 mm x 2.1mm I.D., 3 microm particle size) that allowed the separation of the gamma- and alpha-tocopherols in less than 6 min. The new direct method (Method I) was compared with other methods. Method II (saponification with ultraviolet/visible detection) determined 24% and 22% less gamma- and alpha-tocopherols, respectively. Method III (saponification with evaporative light scattering detection) gave the same values for alpha-tocopherol content as Method II. However, the amount of sample used in the application of Method III was higher than that used in Method II. Furthermore, Method I uses smaller amounts of solvents, and it is simpler and faster than Methods II or III. Only a small volume of sample is needed, which is an additional advantage for biological assays.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Leite Humano/química , Espectrofotometria Ultravioleta/métodos , alfa-Tocoferol/análise , gama-Tocoferol/análise , Humanos , Luz , Espalhamento de Radiação
7.
J Chromatogr A ; 1116(1-2): 204-8, 2006 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16584741

RESUMO

A new method for the determination of phospholipid fatty acids in biological samples, combination of solid-phase extraction (SPE) and fast gas chromatography (GC) was developed. Its application to human plasma and human erythrocytes showed to be robust and reliable for quick and correct identification in routine analysis.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Fosfolipídeos/química , Eritrócitos/química , Humanos , Padrões de Referência , Reprodutibilidade dos Testes
8.
Artigo em Inglês | MEDLINE | ID: mdl-16326086

RESUMO

Here we studied whether the chemical structure of dietary arachidonic and docosahexaenoic acids in full-term infant diets affects their incorporation into erythrocyte membrane phospholipids. From birth to 3 months, infants were fed breast milk (n = 9) or formula milk containing arachidonic acid and docosahexaenoic acid provided by egg phospholipids (n = 10) or by low-eicosapentaenoic acid fish oil and fungal triglycerides (n = 10). We compared the fatty acid composition of erythrocyte phosphatidylethanolamine, phosphatidylcholine and sphingomyelin before and after administration of the experimental diet. At 3 months, infants on formula milk showed lower concentrations of docosahexaenoic acid (in phosphatidylcholine and in phosphatidylethanolamine) and arachidonic acid (in phosphatidylcholine) than those receiving breast milk. We conclude the incorporation of the two fatty acids into erythrocyte phospholipids depends mainly on the lipid composition of the diet received rather than the chemical form in which they are delivered.


Assuntos
Ácidos Araquidônicos/análise , Membrana Celular/química , Ácidos Docosa-Hexaenoicos/análise , Eritrócitos/química , Fórmulas Infantis , Disponibilidade Biológica , Ovos , Feminino , Humanos , Lactente , Fórmulas Infantis/administração & dosagem , Fórmulas Infantis/química , Recém-Nascido , Masculino , Fosfolipídeos/administração & dosagem
9.
Artigo em Inglês | MEDLINE | ID: mdl-16263341

RESUMO

Vitamin C is an antioxidant that can be considered a possible biomarker of oxidative stability in human milk. A high-performance liquid chromatographic method was developed and validated for determining the total Vitamin C (ascorbic acid and dehydroascorbic acid) and ascorbic acid levels in human milk. This method was then compared with an enzymatic method (a Colorimetric technique) for quantifying ascorbic acid levels. Repeatability and reproducibility were acceptable for all methods. However, the high-performance liquid chromatography (HPLC) technique provided more satisfactory results than the enzymatic method due to this last method detected 37% less ascorbic acid and does not determine the total Vitamin C because of the enzymatic method cannot reduce the dehydroascorbic acid (DHA) to ascorbic acid. Furthermore, the HPLC method has the added advantages that it requires less reagents and material, and is simpler and less time consuming than the enzymatic method. In conclusion, the drawbacks of this enzymatic method would justify its substitution for a HPLC method.


Assuntos
Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão/métodos , Enzimas/química , Leite Humano/química , Humanos , Espectrofotometria Ultravioleta
10.
J Chromatogr A ; 1046(1-2): 235-9, 2004 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-15387193

RESUMO

Powder infant milk formula quality deterioration and consequently the termination of shelf life results in the appearance of off-flavors mainly determined by a composite effect of spoilage volatiles. A headspace gas chromatographic method to determine propanal, pentanal and hexanal as the main volatiles present in the headspace of powder infant formula oxidation is described as a rapid indication of oxidative status. Under optimum conditions the limits of detection for propanal, pentanal and hexanal were 17.19, 16.87 and 19.60 ng and the limits of quantification were 37.37, 31.96 and 35.97, respectively. The calibration graphs of the method were linear from 25 to 1500, 20 to 3500 and 30 to 8500 ng for propanal, pentanal and hexanal, respectively, with determination coefficients exceeding 0.99. The precision results showed that the relative standard deviations of the repeatability and reproducibility were between 2.2 and 5.5%. The analytical method was simple, rapid, and reliable and permitted the analysis of a large number of formulas using small sample volumes.


Assuntos
Cromatografia Gasosa/métodos , Alimentos Infantis/análise , Calibragem , Humanos , Recém-Nascido , Reprodutibilidade dos Testes , Volatilização
11.
Eur J Clin Nutr ; 57(12): 1621-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14647228

RESUMO

OBJECTIVES: To determine which triacylglycerol (TAG) species in mature human milk are less affected by external factors and may thus be considered as TAG markers, as well as to determine which species are most influenced by these external conditions. Furthermore, we examine the correlation between the TAG markers and their fatty acids (FAs). SETTING AND SUBJECTS: Six healthy women from Barcelona (Catalonia, Spain). DESIGN AND INTERVENTIONS: In order to obtain the maximum variability of sampling conditions, 40 mature human milk samples were collected from different mothers, on different days, at different times of the day, and from different breasts during and after both the baby's and mother's meal. TAG and FA profiles were determined and correlated. The TAG composition was determined by high-performance liquid chromatography with an evaporative light-scattering detector, and also with atmospheric pressure chemical ionisation mass spectrometry. FAs compositions were determined by gas chromatography. RESULTS: The results were analysed using the SPSS statistical package and proved to be more variable than might have been found in a more restrictive sample design. Nevertheless, despite these conditions, some TAG species were found in relatively constant levels in mature human milk, and could thus be considered as markers of the mature milk TAG profile. TAG species that we can classify in this group were: LaMO, CaPO, LaCaO, LaPCa, LaOL, MPLn, LLO, LaOO, MPL, and MOL. The names do not indicate the location of fatty acids in the glycerol molecule. On the other hand, concentrations of other TAG species vary considerably between samples and consequently these may be understood to be especially affected by the external factors. TAGs like PaLS, MPO, PaOO, PPP, MPS, SPP, LOO, PPO, MOS, SSP, POL, and SOS are in this second group. Correlation between the TAG markers and their FAs was examined by Pearson's test and a significant correlation was found for some FAs. CONCLUSIONS: The TAG species present in mature human milk are affected in different ways by external factors such as dietary intake, nutritional status, length of lactation, time of the day, etc. Some TAGs may be considered as markers of mature human milk as they are relatively constant under a wide range of sampling conditions and do not depend on the factors mentioned. SPONSORSHIP: This study was supported by the Fundació Mestres Jané.


Assuntos
Dieta , Ácidos Graxos/análise , Lactação/metabolismo , Leite Humano/química , Triglicerídeos/análise , Adulto , Biomarcadores/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos/química , Feminino , Humanos , Estado Nutricional , Espanha , Fatores de Tempo , Triglicerídeos/química
12.
Eur J Clin Nutr ; 56(2): 114-20, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11857044

RESUMO

OBJECTIVE: To measure the incorporation of oleic acid and antioxidants (phenols and vitamin E) to low density lipoprotein (LDL) after acute and short-term ingestion of virgin olive oil. To study whether this incorporation contributes to an increase in LDL resistance to oxidation. SETTING: Department of Food and Nutrition, University of Barcelona, Spain and Department of Lipids and Cardiovascular Epidemiology, IMIM, Barcelona, Spain. SUBJECTS: Sixteen healthy volunteers aged 25-65 y. DESIGN AND INTERVENTIONS: To observe the change in the fatty acid profile, vitamin E, phenolic compounds and LDL oxidation-related variables after the postprandial phase and after daily ingestion of olive oil for one week. RESULTS: Few changes were observed in the postprandial phase. However, after a week of olive oil consumption there was an increase in oleic acid (P=0.015), vitamin E (P=0.047), phenolics (P=0.021) and lag time (P=0.000), and a decrease in the maximum amount of dienes (P=0.045) and oxidation rate (P=0.05). CONCLUSION: After ingestion of virgin olive oil, an increase in antioxidants and oleic acid in LDL was observed as well as an improvement of LDL resistance to oxidation. Our results support the idea that daily ingestion of virgin olive oil could protect LDL from oxidation. SPONSORSHIP: This study was supported by a research grant from Spain (ALI 97-1607-C02-02).


Assuntos
Antioxidantes/farmacologia , Lipoproteínas LDL/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Óleos de Plantas/farmacologia , Adulto , Idoso , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Azeite de Oliva , Oxirredução , Fenóis/administração & dosagem , Fenóis/metabolismo , Fenóis/farmacologia , Óleos de Plantas/administração & dosagem , Óleos de Plantas/metabolismo , Período Pós-Prandial , Vitamina E/administração & dosagem , Vitamina E/metabolismo , Vitamina E/farmacologia
13.
J Chromatogr B Biomed Sci Appl ; 758(2): 315-22, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11486843

RESUMO

A reversed-phase HPLC method with diode-array detection was used to simultaneously determine retinol, alpha-tocopherol and beta-carotene in human plasma and low-density lipoproteins. An aliquot of sample was de-proteinized with ethanol containing beta-tocopherol acetate as internal standard, and the analytes were extracted twice with hexane. The solvent was evaporated to dryness under a stream of nitrogen and the residue was redissolved in methanol to be injected directly into the HPLC system. A multiple solvent system based on methanol, butanol and water at a flow-rate of 2 ml/min and held at 45 degrees C provided clear separation of these compounds in only 8 min. The method showed good linearity, precision and accuracy for all compounds. Owing to its simplicity, this method may be useful in routine clinical and epidemiological work.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lipoproteínas LDL/química , Vitamina A/sangue , alfa-Tocoferol/sangue , beta Caroteno/sangue , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Vitamina A/análise , alfa-Tocoferol/análise , beta Caroteno/análise
14.
Bol. pediatr ; 41(175): 9-16, 2001. ilus, tab
Artigo em Es | IBECS | ID: ibc-585

RESUMO

Introducción: La ecografía sigue siendo el método de estudio inicial de las malformaciones fetales, sin embargo, existen condiciones especiales y limitaciones que hacen de la resonancia magnética el método útil en estas circunstancias proporcionando un gran detalle de la anatomía y patología fetal. Objetivos: Determinar el valor de la resonancia magnética en el estudio de la patología fetal. Material y métodos: Se estudiaron en nuestro Centro mediante resonancia magnética 26 gestantes con la sospecha de malformaciones fetales mediante ecografía: 15 presentaban anomalías intracraneales, 1 pulmonar,1 diafragmática, 5 renales, 2 pélvicas 1 anomalía de columna vertebral y un embarazo gemelar siamés. Resultados: En nuestra experiencia, la resonancia magnética aportó información adicional en 6 de las 26 pacientes (23,07 por ciento) modificando la actitud terapéutica en 3 de ellas (11,03 por ciento); en 2 pacientes (7,6 por ciento) no identificó las alteraciones detectadas mediante ecografía. Conclusiones: La ecografía sigue siendo el método de estudio inicial de las malformaciones fetales. En los últimos años la aparición de nuevas secuencias rápidas y poco sensibles al movimiento han permitido el estudio del feto por resonancia magnética. Existen condiciones en las cuales la ecografía presenta limitaciones siendo en estas situaciones la resonancia magnética de gran utilidad pudiendo aportar información adicional que en ocasiones influye en el manejo de estos pacientes (AU)


Assuntos
Gravidez , Feminino , Humanos , Anormalidades Congênitas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal/métodos , Anormalidades Congênitas , Ultrassonografia Pré-Natal/métodos , Hérnia Diafragmática/diagnóstico , Síndrome de Dandy-Walker/diagnóstico , Corpo Caloso/anormalidades , Defeitos do Tubo Neural/diagnóstico , Encefalopatias/diagnóstico
16.
J Chromatogr A ; 881(1-2): 251-4, 2000 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-10905708

RESUMO

A quick and direct method for measuring tocopherols (alpha, beta+gamma and delta) in vegetable oils has been developed using RP-HPLC with UV detection. Previous extraction of tocopherols is not required. The oil is diluted in hexane and an aliquot is mixed with ethanol containing an internal standard (alpha-tocopherol acetate). The chromatographic system consists of an ODS-2 column with a methanol-water mobile phase. Tocopherols are detected at 292 nm in less than 5 min after injection. The method is precise (RSD=2.69%) and has a high mean recovery (98.14%).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Óleos de Plantas/química , Vitamina E/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
17.
J Chromatogr A ; 881(1-2): 255-9, 2000 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-10905709

RESUMO

A reversed-phase high-performance liquid chromatographic method was developed for the determination, in one run, of alpha-tocopherol and beta-carotene in virgin olive oil. The method involved a rapid saponification and a later extraction with a mixture of hexane-ethyl acetate. The chromatographic system consists of an ODS-2 column with a mobile phase of methanol-water-butanol and a diode-array detector. Linearity, precision, recovery and sensitivity were satisfactory. The main advantage of the proposed method is the speed and simultaneous determination of both compounds at the same time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Óleos de Plantas/química , Vitamina E/análise , beta Caroteno/análise , Azeite de Oliva , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
18.
Radiographics ; 19(3): 583-600, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10336190

RESUMO

Cervicothoracic lesions are not uncommon in children. All cervicothoracic lesions except superficial lesions extend from the neck to the thorax through the thoracic inlet. Evaluation of this area involves multiple imaging modalities: plain radiography, ultrasonography, nuclear medicine, computed tomography, and magnetic resonance (MR) imaging. However, MR imaging is the method of choice for assessing the full extents of cervicothoracic lesions and their relationships to neurovascular structures. Cervicothoracic lesions can be classified as congenital lesions, inflammatory lesions, benign tumors, malignant tumors, and traumatic lesions. Lymphangioma is the most common cervicothoracic mass in children; other congenital lesions include hemangioma, thymic cyst, and vascular anomalies. Inflammatory adenopathy reactive to tuberculosis, mononucleosis, tularemia, cat-scratch fever, infection with human immunodeficiency virus, or other upper respiratory tract infections can manifest as cervicothoracic lesions; tuberculous abscesses and abscesses of other origins can also be seen. Lipoma, lipoblastoma, aggressive fibromatosis, and nerve sheath tumors (either isolated lesions or those associated with neurofibromatosis) can also occur as cervicothoracic masses. Malignant cervicothoracic tumors include lymphoma, thyroid carcinoma, neuroblastoma, and chest wall tumors (rhabdomyosarcoma, Ewing sarcoma, and neuroectodermal tumor). Traumatic cervicothoracic lesions include pneumomediastinum of traumatic origin, traumatic pharyngeal pseudodiverticulum, esophageal foreign-body granuloma, and cervicothoracic hematoma.


Assuntos
Diagnóstico por Imagem , Pescoço/patologia , Doenças Torácicas/diagnóstico , Adolescente , Doença da Arranhadura de Gato/diagnóstico , Criança , Pré-Escolar , Feminino , Infecções por HIV/diagnóstico , Neoplasias de Cabeça e Pescoço/diagnóstico , Hemangioma/diagnóstico , Humanos , Lactente , Recém-Nascido , Mononucleose Infecciosa/diagnóstico , Linfadenite/diagnóstico , Linfangioma/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Cisto Mediastínico/diagnóstico , Pescoço/anormalidades , Pescoço/diagnóstico por imagem , Lesões do Pescoço/diagnóstico , Cintilografia , Infecções Respiratórias/diagnóstico , Estudos Retrospectivos , Doenças Torácicas/congênito , Doenças Torácicas/diagnóstico por imagem , Traumatismos Torácicos/diagnóstico , Neoplasias Torácicas/diagnóstico , Tomografia Computadorizada por Raios X , Tuberculose dos Linfonodos/diagnóstico , Tularemia/diagnóstico , Ultrassonografia
19.
Eur Radiol ; 8(7): 1236-44, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9724445

RESUMO

Pancreatic disorders are not rare in children. Modern imaging equipment allows recognition of many pancreatic diseases that were difficult to identify in the past and therefore were considered to be unusual. Within the scope of this article we include information on imaging modalities for studying the pancreas and a description of the radiologic manifestations of the most common congenital, inflammatory, tumoral, traumatic and systemic disorders.


Assuntos
Pancreatopatias/diagnóstico , Criança , Pré-Escolar , Diagnóstico por Imagem , Humanos , Pâncreas/anormalidades , Pâncreas/lesões
20.
Acta Otorrinolaringol Esp ; 48(4): 269-74, 1997 May.
Artigo em Espanhol | MEDLINE | ID: mdl-9376136

RESUMO

The structure of human tympanic bones and their articulations was studied. Martin's trichrome stain of serial sections revealed the transmission paths of force lines based on bone lamellae density and acid fuchsin staining, which disclosed functional "critical points" (mechanical solicitation). This study contributed basic knowledge and a morphological and functional classification of the incudomalieotar and incudostapedial joints. The incudomalieolar joint was confirmed as a "riding saddle" but the incudostapedial joint as a "spheroid joint" was questioned. Information on capsule structure the meniscus and articular cartilage of the incudomalleolar joint is given.


Assuntos
Cartilagem Articular/anatomia & histologia , Ossículos da Orelha/anatomia & histologia , Orelha Média/anatomia & histologia , Densidade Óssea , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...