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1.
Front Cardiovasc Med ; 9: 953894, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262204

RESUMO

Background: Vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited connective tissue disorder due to pathogenic variants in COL3A1 leading to medium-size-artery (MSA) dissection, aneurysm, rupture. Aortic lesions are rarer and less investigated. The objective was to describe the distribution of MSA and aortic lesions and the type of COL3A1 variants in a multicentric cohort of 330 adult vEDS patients. Methods: At the time of the study, 87% were alive, 60.3% were index cases, and 60.0% were women. COL3A1 variants were identified using NGS and/or Sanger sequencing and classified according to functional consequences: 80.6% leading to dominant-negative (DN) and 19.4% leading to haploinsufficiency (HI). Imaging was systematically performed during the initial workup. Carotid mechanics were assessed by echo tracking in a subgroup of patients. Results: Arterial lesions were reported in 82.4% of the patients (N = 272): 83.5% had MSA lesions alone, 3.3% had aortic lesions alone, and 13.2% both. DN variants were associated with a higher prevalence of arterial lesions (P < 0.044), especially in supra-aortic trunks and renal arteries. The prevalence of aortic lesions in HI patients with arterial lesions was higher than that in patients with DN (P 0.027), but not anymore when adjusted for age (P < 0.559). Carotid Young's modulus was lower in patients with DN, in association with the higher incidence of MSA lesions in this group. Conclusion: The prevalence of aortic lesions is not influenced by the COL3A1 genotype when adjusted for age. Patients with DN variant vEDS have a higher frequency of MSA lesions, especially in supra-aortic trunks associated with lower carotid stiffness. These results support optimized care and follow-up for these vulnerable patients.

2.
Respiration ; 101(1): 34-45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515219

RESUMO

BACKGROUND: There is growing evidence of gender-specific phenotypic differences among patients with idiopathic pulmonary fibrosis (IPF), which may affect patient outcomes. OBJECTIVES: We present the characteristics of patients with IPF at inclusion in the French Rare Disease Cohort - Interstitial Lung Disease (RaDiCo-ILD) with the aim of characterizing gender-specific phenotypic differences. METHODS: Patients with IPF who were enrolled in the national, multicentre RaDiCo-ILD cohort were included. Demographic characteristics, comorbidities, health-related quality of life (HRQoL) scores, pulmonary function, chest imaging, and IPF treatment were collected at inclusion and described by gender. RESULTS: The cohort included 724 patients with IPF (54% of RaDiCo-ILD cohort), of whom 82.9% were male. The proportion of male and female patients with a prior history of smoking was 75.0% and 26.8%, respectively. Emphysema was present in 17.0% (95% confidence interval [CI]: 10.0, 24.0) of men and 5.4% (95% CI: 1.2, 9.6) of women. At inclusion, females had poorer HRQoL than males based on St. George's Respiratory Questionnaire scores (48.5 [95% CI: 43.9, 53.0] and 41.5 [39.4, 43.6], respectively). The mean forced vital capacity per cent predicted was 77.7% (95% CI: 76.2, 79.3) and 87.4% (83.4, 91.4) for males and females, respectively. Honeycombing on high-resolution computed tomography (HRCT) was present in 70.8% (95% CI: 61.0, 80.6) of males and 45.8% (95% CI: 35.1, 56.5) of females. CONCLUSIONS: This analysis of patients with IPF at inclusion in the RaDiCo-ILD cohort provides evidence that comorbid emphysema, lung volume reduction, and honeycombing on HRCT are more common characteristics of males than females.


Assuntos
Enfisema , Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Estudos de Coortes , Feminino , Humanos , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Fibrose Pulmonar Idiopática/epidemiologia , Masculino , Qualidade de Vida , Doenças Raras
3.
Adv Ther ; 39(1): 405-420, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34757602

RESUMO

INTRODUCTION: Pirfenidone, an antifibrotic medication for idiopathic pulmonary fibrosis (IPF), is now available in France in two formulations: tablets since April 2018, and the initial capsules form. We conducted a cohort study to describe tolerance and acceptability of capsules and/or tablets of pirfenidone in patients with IPF. METHODS: This study was nested within the French, non-randomized, multicenter RaDiCo-ILD (Rare Disease Cohort-Interstitial Lung Diseases). Included patients with IPF received at least one dose of pirfenidone tablets or capsules from July 2017 to June 2019 in three populations: the inclusion population (patients treated at least once with pirfenidone during the study period, n = 288); the potential switch population (patients treated with pirfenidone during the switch period starting April 2018, n = 256); the newly treated population (patients who initiated pirfenidone during the study period, n = 162). Each of those last two populations included three subgroups (tablets, capsules, and substitution). RESULTS: In 288 patients treated, 162 newly initiated pirfenidone during the study period: there were no meaningful differences in the baseline characteristics with the 256 patients treated during the potential switch period. In the newly treated population, 30.3% started pirfenidone treatment with tablet formulation. In the potential switch population, 44.9% of patients shifted from capsule to tablet. Half of the patients shifted to tablet formulation within the first 10 months. The mean treatment duration was 21.5 months with a mean dose of 2106.7 mg/day; 46.5% of patients discontinued treatment, mainly because of adverse events. There were fewer discontinuations in the tablets and substitution subgroups than in the capsules-only subgroup. The most reported adverse event was skin rash (11.5%). No new adverse event was identified. CONCLUSIONS: This real-life cohort assessing the characteristics of the prescription of pirfenidone tablets and capsules suggests a good acceptability of the tablet formulation by patients with IPF. TRIAL REGISTRATION: Clinical trial registered with www.clinicaltrials.gov (NCT04238871).


Assuntos
Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Piridonas/uso terapêutico , Estudos de Coortes , França , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Comprimidos/uso terapêutico , Resultado do Tratamento
4.
Orphanet J Rare Dis ; 16(1): 454, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34715889

RESUMO

BACKGROUND: Rare diseases (RDs) affect nearly 3 million people in France and at least 26-30 million people in Europe. These diseases, which represent a major medical concern, are mainly of genetic origin, often chronic, progressive, degenerative, life threatening and disabling, accounting for more than one third of all deaths occurring during infancy. In this context, there are needs for coordinated information on RDs at national/international levels, based on high quality, interoperable and sharable data. The main objective of the RaDiCo (Rare Disease Cohorts) program, coordinated by Inserm, was the development of RD e-cohorts via a national platform. The cohort projects were selected through a national call in 2014. The e-cohorts are supported by an interoperable platform, equivalent to an infrastructure, constructed on the "cloud computing" principle and in compliance with the European General Data Protection Regulation. It is dedicated to allow a continuous monitoring of data quality and consistency, in line with the French Health Data Hub. RESULTS: Depending on cohorts, the objectives are to describe the natural history of the studied RD(s), identify the underlying disease genes, establish phenotype-genotype correlations, decipher their pathophysiology, assess their societal and medico-economic impact, and/or identify patients eligible for new therapeutic approaches. Inclusion of prevalent and incident cases started at the end of 2016. As of April 2021, 5558 patients have been included within 13 RD e-cohorts covering 67 diseases integrated in 10 European Reference Networks and contributing to the European Joint Program on RDs. Several original results have been obtained in relation with the secondary objectives of the RaDiCo cohorts. They deal with discovery of new disease genes, assessment of treatment management, deciphering the underlying pathophysiological mechanisms, diagnostic approaches, genotype-phenotype relationships, development and validation of questionnaires relative to disease burden, or methodological aspects. CONCLUSION: RaDiCo currently hosts 13 RD e-cohorts on a sharable and interoperable platform constructed on the "cloud computing" principle. New RD e-cohorts at the European and international levels are targeted.


Assuntos
Doenças Raras , Europa (Continente) , França/epidemiologia , Humanos , Doenças Raras/epidemiologia , Doenças Raras/genética
5.
Mol Autism ; 10: 22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31123562

RESUMO

Background: Autism spectrum disorders (ASD) are characterized by abnormal neurodevelopment, genetic, and environmental risk factors, as well as immune dysfunctions. Several lines of evidence suggest alterations in innate immune responses in children with ASD. To address this question in adults with high-functioning ASD (hf-ASD), we sought to investigate the role of natural killer (NK) cells in the persistence of ASD. Methods: NK cells from 35 adults with hf-ASD were compared to that of 35 healthy controls (HC), selected for the absence of any immune dysfunctions, at different time-points, and over a 2-year follow-up period for four patients. The phenotype and polyfunctional capacities of NK cells were explored according to infectious stigma and clinical parameters (IQ, social, and communication scores). Results: As compared to HC, NK cells from patients with hf-ASD showed a high level of cell activation (p < 0.0001), spontaneous degranulation (p < 0.0001), and interferon-gamma production (p = 0.0004), whereas they were exhausted after in vitro stimulations (p = 0.0006). These data yielded a specific HLA-DR+KIR2DL1+NKG2C+ NK-cell signature. Significant overexpression of NKG2C in hf-ASD patients (p = 0.0005), indicative of viral infections, was inversely correlated with the NKp46 receptor level (r = - 0.67; p < 0.0001), regardless of the IgG status of tested pathogens. Multivariate linear regression analysis also revealed that expression of the late-activating HLA-DR marker was both associated with structural language (r = 0.48; p = 0.007) and social awareness (r = 0.60; p = 0.0007) scores in adult patients with hf-ASD, while KIR2DL1 expression correlated with IQ scores (p = 0.0083). Conclusions: This study demonstrates that adults with hf-ASD have specific NK-cell profile. Presence of NKG2C overexpression together with high-level activation of NK cells suggest an association with underlying pathogens, a hypothesis warranting further exploration in future studies.


Assuntos
Transtorno do Espectro Autista/imunologia , Infecções/imunologia , Células Matadoras Naturais/imunologia , Adolescente , Adulto , Análise por Conglomerados , Comunicação , Feminino , Humanos , Testes de Inteligência , Masculino , Pessoa de Meia-Idade , Fenótipo , Receptores KIR2DL1/genética , Receptores KIR2DL1/metabolismo , Comportamento Social , Adulto Jovem
6.
Sci Transl Med ; 11(481)2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30814340

RESUMO

Despite the high clinical burden, little is known about pathophysiology underlying autism spectrum disorder (ASD). Recent resting-state functional magnetic resonance imaging (rs-fMRI) studies have found atypical synchronization of brain activity in ASD. However, no consensus has been reached on the nature and clinical relevance of these alterations. Here, we addressed these questions in four large ASD cohorts. Using rs-fMRI, we identified functional connectivity alterations associated with ASD. We tested for associations of these imaging phenotypes with clinical and demographic factors such as age, sex, medication status, and clinical symptom severity. Our results showed reproducible patterns of ASD-associated functional hyper- and hypoconnectivity. Hypoconnectivity was primarily restricted to sensory-motor regions, whereas hyperconnectivity hubs were predominately located in prefrontal and parietal cortices. Shifts in cortico-cortical between-network connectivity from outside to within the identified regions were shown to be a key driver of these abnormalities. This reproducible pathophysiological phenotype was partially associated with core ASD symptoms related to communication and daily living skills and was not affected by age, sex, or medication status. Although the large effect sizes in standardized cohorts are encouraging with respect to potential application as a treatment and for patient stratification, the moderate link to clinical symptoms and the large overlap with healthy controls currently limit the usability of identified alterations as diagnostic or efficacy readout.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Rede Nervosa/fisiopatologia , Adolescente , Estudos de Coortes , Feminino , Humanos , Masculino
7.
Therapie ; 67(1): 11-42, 2012.
Artigo em Francês | MEDLINE | ID: mdl-22487500

RESUMO

Clinical Investigation Centres (CICs) are academic organisations for performing clinical studies. They are a part of a national network which is co-ordinated by French national institute for health and medical research (Inserm), and the head office of healthcare provision (DGOS). There are working groups and specialised networks within the overall CIC network. The Harmonisation of CIC Procedures (HPCIC) group wrote a manual of good professional practices for clinical research. This manual is described here. This manual was written by consensus. It was approved by the coordinators of all CICs, external experts, and validated by representatives of both Inserm and the General directorate of healthcare provision (DGOS). The CIC Good Professional Practices manual is a guide divided into two sections. The first section covers the general management of a CIC (common to all CICs). The second section covers the core activities of CICs, running clinical studies (clinical study coordination, clinical investigation, data management, statistical analysis, valorisation). This manual is available for all CICs and any other clinical research organisations. It will serve as a basis for CIC self-quality evaluation, audits between CICs, and external audits. This manual shows how much the CICs want to standardise practices and procedures nationwide to offer their partners the best quality in performing clinical studies.


Assuntos
Pesquisa Biomédica/normas , Pesquisa Biomédica/organização & administração , França , Guias como Assunto , Humanos , Auditoria Administrativa , Reprodutibilidade dos Testes
8.
Therapie ; 67(1): 11-42, 2012.
Artigo em Francês | MEDLINE | ID: mdl-27393657

RESUMO

Clinical Investigation Centres (CICs) are academic organisations for performing clinical studies. They are a part of a national network which is co-ordinated by French national institute for health and medical research (Inserm), and the head office of healthcare provision (DGOS). There are working groups and specialised networks within the overall CIC network. The Harmonisation of CIC Procedures (HPCIC) group wrote a manual of good professional practices for clinical research. This manual is described here. This manual was written by consensus. It was approved by the coordinators of all CICs, external experts, and validated by representatives of both Inserm and the General directorate of healthcare provision (DGOS). The CIC Good Professional Practices manual is a guide divided into two sections. The first section covers the general management of a CIC (common to all CICs). The second section covers the core activities of CICs, running clinical studies (clinical study coordination, clinical investigation, data management, statistical analysis, valorisation). This manual is available for all CICs and any other clinical research organisations. It will serve as a basis for CIC self-quality evaluation, audits between CICs, and external audits. This manual shows how much the CICs want to standardise practices and procedures nationwide to offer their partners the best quality in performing clinical studies.

9.
J Am Coll Nutr ; 26(6): 655-62, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18187430

RESUMO

BACKGROUND: Carotenoids are mainly carried by lipoproteins in blood, however little is known about the influence of polymorphisms of apolipoproteins (apo), cholesterol ester transfer protein (CETP) and lipoprotein lipase (LPL) involved in serum lipid metabolism. OBJECTIVE: We aimed to analyze whether serum concentrations of 5 carotenoids (lutein-zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, beta-carotene) are associated with common polymorphisms of Apo E, Apo B, Apo CIII, CETP, and LPL. METHODS: Serum concentrations of lutein-zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, and beta-carotene were measured and polymorphisms of Apo E (cys112arg and arg158cys), Apo B (thr71ile), Apo CIII [C(-482)T, Apo CIII T(-455)C, Apo CIII C1100T, Apo CIII C3175G, Apo CIII T3206G], CETP (ile405val), and LPL (S447X) were determined in a sample of 447 children and adults drawn from the Stanislas Study. RESULTS: After adjustment for age, sex, smoking, physical activity, oral contraceptive use, BMI, serum cholesterol and triglyceride concentrations, and fruit and vegetable intakes, carriers vs. non carriers of the lipoprotein lipase X447 allele had significant lower concentrations of lutein-zeaxanthin, beta-cryptoxanthin, alpha-carotene and beta-carotene; differences vs. S447S genotype being the largest for X447X: -18.8%, -50.5%, -54.8% and -47.1%, for the four carotenoid fractions, respectively. No significant association was noticed for lycopene concentration. None of the other tested polymorphisms was significantly related to the serum carotenoid concentrations. CONCLUSIONS: Our investigation for the first time demonstrates that LPL S447X polymorphism could alter serum concentrations of carotenoids in healthy individuals, independently of serum cholesterol and triglyceride concentration. These data indicate that genetic factors could be involved in the variability of carotenoid bioavailability and bioconversion.


Assuntos
Apolipoproteínas/genética , Carotenoides/sangue , Proteínas de Transferência de Ésteres de Colesterol/genética , Metabolismo dos Lipídeos/genética , Lipase Lipoproteica/genética , Polimorfismo Genético , Adolescente , Adulto , Disponibilidade Biológica , Criança , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
10.
Am J Clin Nutr ; 81(5): 1034-44, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15883426

RESUMO

BACKGROUND: Although numerous environmental factors are documented to influence serum retinol and alpha-tocopherol concentrations, little is known about the genetic versus the environmental contributions to variations in these traits. OBJECTIVE: The aim of this study was to estimate additive genetic heritability and household effects for serum retinol and alpha-tocopherol concentrations in a variance component analysis. DESIGN: In a sample of 387 French families, information on serum retinol and alpha-tocopherol concentrations, usual dietary intake, lifestyle, and serum lipid profiles and related polymorphisms (apolipoprotein E, apolipoprotein C-III, apolipoprotein B, cholesteryl ester transfer protein, and lipoprotein lipase) was obtained. RESULTS: For serum retinol--after adjustment for sex, age, body mass index, alcohol consumption, oral contraceptive use, and serum albumin, triacylglycerol, and apolipoprotein A-I concentrations--additive genetic effects and shared common environment contributed 30.5% and 14.2% of the total variance, respectively. For serum alpha-tocopherol, approximately 22.1% of the total variance was due to the additive effects of genes and 18.7% to those of household environment, after adjustment for the covariates sex, age, vitamin E intake, oral contraceptive use, and cholesterol, triacylglycerol, and apolipoprotein A-I concentrations. For both vitamins, the influence of measured polymorphisms was not significant. Moreover, heritability and household effect estimates were not significantly different between the 4 classes of relatives and did not vary significantly when families shared more meals at home. CONCLUSIONS: The results show that serum retinol and alpha-tocopherol concentrations are under genetic control in healthy families.


Assuntos
Antioxidantes/metabolismo , DNA/genética , Dieta , Meio Ambiente , Família , Vitamina A/sangue , alfa-Tocoferol/sangue , Adolescente , Adulto , Distribuição por Idade , Alelos , Criança , Feminino , Genótipo , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo
11.
J Am Coll Nutr ; 22(4): 303-10, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12897045

RESUMO

OBJECTIVE: To test the effect of a 21-day supplementation with moderate doses of antioxidant nutrients on biochemical indicators of vitamin, carotenoid and trace element levels in alcohol-dependent patients during a program of alcohol rehabilitation. DESIGN: A randomized double-blind trial was performed comparing two groups receiving daily either a combination of micronutrients (beta-carotene: 6 mg, vitamin C: 120 mg, vitamin E: 30 mg, zinc: 20 mg, selenium: 100 micro g) or a placebo. SUBJECTS: 106 alcohol-dependent patients 20 to 60 years of age without severe liver disease, hospitalized for a 21-day rehabilitation program. Measure of Outcome: Vitamin C, retinol, alpha-tocopherol, zeaxanthin/lutein, beta-cryptoxanthin, lycopene, alpha- and beta-carotene, zinc and selenium were measured in serum, initially and after supplementation. RESULTS: (1) In the placebo group, after 21 days of rehabilitation, serum concentrations of vitamin C and all five carotenoids significantly increased, whereas retinol and alpha-tocopherol concentrations decreased; zinc and selenium levels were unaffected. (2) At the end of the hospital stay, serum indicators were significantly improved in the supplement group as compared to the placebo group for vitamin C, alpha-tocopherol, beta-carotene, zinc and selenium; conversely, lycopene changes were higher in the placebo group than in supplement group. (3) Of the serum antioxidants measured at entrance, only vitamin C was significantly depleted in heavy smokers, and, after the supplementation period, vitamin C was efficiently repleted in this later group. CONCLUSION: Our results indicate that a short-term supplementation with physiological doses of antioxidant vitamins, carotenoids and trace elements during alcohol rehabilitation clearly improves micronutrient status indicators. Heavy smokers in particular seem to respond to vitamin C supplementation.


Assuntos
Alcoolismo/reabilitação , Antioxidantes/administração & dosagem , Micronutrientes/administração & dosagem , Micronutrientes/sangue , Adulto , Alcoolismo/sangue , Antioxidantes/análise , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Carotenoides/administração & dosagem , Carotenoides/sangue , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Selênio/administração & dosagem , Selênio/sangue , Vitamina A/administração & dosagem , Vitamina A/sangue , Zinco/administração & dosagem , Zinco/sangue , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/sangue
12.
Alcohol Clin Exp Res ; 26(4): 501-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11981126

RESUMO

BACKGROUND: Apolipoprotein (Apo) E genotype and alcohol consumption or withdrawal strongly affect lipoprotein (Lp) metabolism and, as with any genetic and environmental factors, they might interact. The aim of this study was to investigate this gene/environment interaction by analyzing the effect of the apoE genotype on the alcohol withdrawal-induced alterations in the serum Apo and Lp profile. METHODS: ApoE genotypes and concentrations of serum cholesterol, triglyceride, and Lps containing apoA-I, A-II, B, E, and C-III were determined in 84 male alcohol abusers before and after 3 weeks of abstinence. RESULTS: After withdrawal, concentrations of serum apoA-I, LpA-I, LpA-I/A-II, apoC-III, LpC-III-non-B, apoE, and LpE-non-B significantly decreased, whereas those of triglycerides and apoB increased; levels of cholesterol, LpC-III:B, and LpB:E were not affected. ANOVA shows that apoE polymorphism effects were quite similar before and after alcohol withdrawal on all serum Apos and Lps (the interaction term between withdrawal and apoE genotype was not significant). The only interaction term that was borderline significant (p < or = 0.10) concerned the apoB concentration. Before withdrawal, no association between apoB level and apoE polymorphism was observed, whereas after abstinence, a borderline significant (p < or = 0.10) gradient of concentration across the three groups of subjects (epsilon2 carriers < epsilon3/epsilon3 < epsilon4 carriers) was noticed. CONCLUSIONS: Alcohol abstinence causes major changes in the antiatherogenic Apos and Lps and may increase those known to be atherogenic. Heavy alcohol consumption seems to alter the effect of apoE polymorphism on apoB levels, and further investigations are needed to clarify the mechanisms involved in this phenomenon: a defect in sialylation of apoE, formation of acetaldehyde adducts on apoB, or both.


Assuntos
Apolipoproteínas E/sangue , Apolipoproteínas E/genética , Lipoproteínas/sangue , Polimorfismo Genético/genética , Síndrome de Abstinência a Substâncias/sangue , Síndrome de Abstinência a Substâncias/genética , Adulto , Alcoolismo/sangue , Alcoolismo/genética , Análise de Variância , Apolipoproteínas/sangue , Apolipoproteínas/genética , Humanos , Lipoproteínas/genética , Masculino , Pessoa de Meia-Idade , Temperança/estatística & dados numéricos
13.
J Chromatogr Sci ; 40(2): 69-76, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11881707

RESUMO

An isocratic high-performance liquid chromatography (HPLC) method for the simultaneous determination of alpha-tocopherol, retinol, and five carotenoids (lutein-zeaxanthin, beta-cryptoxanthin, lycopene, and alpha- and beta-carotene) in human serum is described. Serum samples are deproteinized with ethanol and extracted once with n-hexane. Resulting extracts are injected onto a C18 reversed-phase column eluted with methanol-acetonitrile-tetrahydrofuran (75:20:5, v/v/v), and full elution of all the analytes is realized isocratically within 20 min. The detection is operated using three channels of a diode-array spectrophotometer at 290, 325, and 450 nm for tocopherol, retinol, and the carotenoids, respectively. An internal standard is used for each channel, which improves precision. The choice of internal standards is discussed, as well as the extraction protocol and the need for adding an antioxidant during the extraction and chromatographic steps. The analytical recoveries for liposoluble vitamins and carotenoids are more than 85%. Intra-assay relative standard deviation (RSD) values (n = 20) for measured concentrations in serum range from 3.3% (retinol) to 9.5% (lycopene), and interassay RSDs (n = 5) range from 3.8% (alpha-tocopherol) to 13.7% (beta-cryptoxanthin). The present method is used to quantitate the cited vitamins in healthy subjects (n = 168) from ages 9 to 55 years old.


Assuntos
Carotenoides/sangue , Cromatografia Líquida de Alta Pressão/métodos , Vitamina A/sangue , alfa-Tocoferol/sangue , Adolescente , Adulto , Criança , Humanos , Pessoa de Meia-Idade , Controle de Qualidade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
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