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1.
Nutrients ; 16(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39203837

RESUMO

Objective: Analyse the breakfast cereal market to help to help healthcare professionals to guide parents in choosing healthy products for their children. Study design: Observational study of the breakfast cereals available in the biggest supermarkets, discount stores and organic chains in France, Belgium and Luxembourg. Methods: An analysis of nutritional qualities using three indicators: Nutri-Score (initial and modified version), WHO Europe nutrient profile model, and Nova. Results: 645 products were listed; 559 excluding duplicates. A total of 28.8% are marketed to children and make up the group of "children's" cereals, 62.1% of cereals are Muesli, Oats and other cereal flakes (MOCF), and 54.9% are "organic". The study shows that "children's" cereals have a poorer nutritional profile: a higher proportion of Nutri-Score D, higher sugar content, lower fibre content, less conformity with the WHO Europe nutrient profile model and a higher proportion ofultra-processed. On the other hand, MOCF and "organic" products generally have a better nutritional profile: less sugar, more fibre, more Nutri-Score A, less Nutri-Score D and fewer ultra-processed products. Conclusions: Parents should therefore opt for cereals that do not bear any reference to children on the packaging.


Assuntos
Desjejum , Grão Comestível , Valor Nutritivo , Humanos , Luxemburgo , Bélgica , Criança , França , Fibras na Dieta/análise , Supermercados
2.
Chemistry ; 19(11): 3655-64, 2013 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-23362183

RESUMO

The deciphering of the binding mode of tyrosinase (Ty) inhibitors is essential to understand how to regulate the tyrosinase activity. In this paper, by combining experimental and theoretical methods, we studied an unsymmetrical tyrosinase functional model and its interaction with 2-hydroxypyridine-N-oxide (HOPNO), a new and efficient competitive inhibitor for bacterial Ty. The tyrosinase model was a dinuclear copper complex bridged by a chelated ring with two different complexing arms (namely (bis(2-ethylpyridyl)amino)methyl and (bis(2-methylpyridyl)amino)methyl). The geometrical asymmetry of the complex induces an unsymmetrical binding of HOPNO. Comparisons have been made with the binding modes obtained on similar symmetrical complexes. Finally, by using quantum mechanics/molecular mechanics (QM/MM) calculations, we studied the binding mode in tyrosinase from a bacterial source. A new unsymmetrical binding mode was obtained, which was linked to the second coordination sphere of the enzyme.


Assuntos
Óxidos N-Cíclicos/farmacologia , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Compostos Organometálicos/farmacologia , Piridinas/farmacologia , Sítios de Ligação , Óxidos N-Cíclicos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Modelos Moleculares , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Piridinas/química , Teoria Quântica , Relação Estrutura-Atividade
3.
Nutrients ; 14(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35011047

RESUMO

Food packaging marketing techniques which appeal to children (such as cartoon characters and brand mascots) affect children's choices, preferences, and eating habits. Several studies have assessed the nutritional quality of food intended to children in various countries and concluded that most were high in fat, salt, and sugar (HFSS) and ultra-processed foods. The aim of this study is to analyse products intended for children over the age of 3 (foods and beverages with relevant marketing elements on the packaging) available on the French market as regards: (1) nutritional quality, based on the Nutri-Score labelling system, (2) compliance with expected nutritional profile suitable for children, according to the criteria of the WHO Europe Nutrient Profile Model, and (3) degree of processing, as defined by the NOVA classification, from packaging collected in 20 stores (hyper/supermarkets, hard-discount retail chains, and organic food stores). The marketing strategies most often used on children's products are cartoons (97.22%; n = 1120) and mascots (77.78%; n = 896). A total of 1155 products were included in the study, most of which were sugary foods: almost a quarter of the products in the sample (23.81%; n = 275) list a sweetener as the first ingredient, and most of them (89.52%; n = 1034) contain free sugars according to the WHO definition. All the products included in our study feature marketing elements targeting on the packaging, yet 94.88% do not meet the criteria of the WHO Europe Nutrient Profile Model. Most (58.68%; n = 676) belong to Nutri-Score groups D and E, with the highest proportion in group D (39.32%; n = 453) and are ultra-processed (87.97%; n = 1016), especially through the use of flavourings and ultra-processed sugars. Using the Nutri-Score, the WHO Europe Nutrient Profile Model, and the NOVA classification, this study suggests that a significant share of pre-packaged foods marketed to children do not have an adequate nutritional profile. As such, measures are needed to regulate what marketing elements aimed at children can be included on packaging, based on these criteria.


Assuntos
Comportamento Infantil/fisiologia , Comportamento de Escolha/fisiologia , Comportamento do Consumidor , Comportamento Alimentar/fisiologia , Manipulação de Alimentos , Rotulagem de Alimentos/métodos , Embalagem de Alimentos/métodos , Marketing/métodos , Valor Nutritivo , Criança , Pré-Escolar , Açúcares da Dieta/análise , Fast Foods/análise , Análise de Alimentos , França , Humanos
4.
J Pediatr Endocrinol Metab ; 33(1): 147-155, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31846426

RESUMO

Background The dietary management of methylmalonic acidaemia (MMA) is a low-protein diet providing sufficient energy to avoid catabolism and to limit production of methylmalonic acid. The goal is to achieve normal growth, good nutritional status and the maintenance of metabolic stability. Aim To describe the dietary management of patients with MMA across Europe. Methods A cross-sectional questionnaire was sent to European colleagues managing inherited metabolic disorders (IMDs) (n=53) with 27 questions about the nutritional management of organic acidaemias. Data were analysed by different age ranges (0-6 months; 7-12 months; 1-10 years; 11-16 years; >16 years). Results Questionnaires were returned from 53 centres. Twenty-five centres cared for 80 patients with MMA vitamin B12 responsive (MMAB12r) and 43 centres managed 215 patients with MMA vitamin B12 non-responsive (MMAB12nr). For MMAB12r patients, 44% of centres (n=11/25) prescribed natural protein below the World Health Organization/Food and Agriculture Organization/United Nations University (WHO/FAO/UNU) 2007 safe levels of protein intake in at least one age range. Precursor-free amino acids (PFAA) were prescribed by 40% of centres (10/25) caring for 36% (29/80) of all the patients. For MMAB12nr patients, 72% of centres (n=31/43) prescribed natural protein below the safe levels of protein intake (WHO/FAO/UNU 2007) in at least one age range. PFAA were prescribed by 77% of centres (n=33/43) managing 81% (n=174/215) of patients. In MMAB12nr patients, 90 (42%) required tube feeding: 25 via a nasogastric tube and 65 via a gastrostomy. Conclusions A high percentage of centres used PFAA in MMA patients together with a protein prescription that provided less than the safe levels of natural protein intake. However, there was inconsistent practices across Europe. Long-term efficacy studies are needed to study patient outcome when using PFAA with different severities of natural protein restrictions in patients with MMA to guide future practice.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/dietoterapia , Proteínas Alimentares/administração & dosagem , Inquéritos e Questionários/normas , Adolescente , Erros Inatos do Metabolismo dos Aminoácidos/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Apoio Nutricional
5.
Early Hum Dev ; 84(9): 561-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18321666

RESUMO

BACKGROUND: The outcome in phenylketonuria is related to the early diagnosis and management due to neonatal screening. AIMS: To assess the interest of tetrahydrobiopterin (BH4) loading test and phenylalanine hydroxylase (PAH) genotyping in the management of neonates with hyperphenylalaninemia (HPA). STUDY DESIGN: We evaluate the effectiveness of a BH4 loading test (20 mg/kg) in ten neonates screened for HPA. We evaluated the time required to reach a target plasma Phenylalanine (Phe) level below 300 micromol/l. We compared these ten BH4-loaded patients to the 10 previous neonates non-loaded with BH4. In all these patients, the PAH genotype was determined. RESULTS: One loaded patient had biopterin synthesis deficiency and has been retrieved from statistical analysis. All others patients have PAH deficiency. Between the BH4 loaded group (L) and the BH4 non-loaded group (NL), a statistically significant difference was observed in the average time required to reached the target Phe level (13.56 +/- 4.30 (L) vs. 20.6 +/- 7.59 days (NL) [p < 0.02]). Results of the genotyping from all but one of these 19 patients indicated that among all mutations present in this patient population, there were 4 known PAH mutations associated with BH4 responsiveness (p.R261Q, the p.V388 M, the p.E390G and the p.Y414C). These mutations were found in 4 non-loaded and 6 loaded patients. Two patients had a more than 90% reduction in their plasma Phe level within 24 h after the load. One of these patients had a PTPS deficiency. The other fully responsive patient (p.Y414C and IVS10-11G>A) has been treated with BH4 from birth with an excellent metabolic control for three years now. CONCLUSION: BH4 loading test improves the management of HPA. It allows an immediate identification of the children fully responsive to BH4. Our results therefore suggest the incorporation of BH4 loading test in the management of neonates screened for HPA.


Assuntos
Biopterinas/análogos & derivados , Programas de Rastreamento , Fenilalanina/sangue , Fenilcetonúrias/diagnóstico , Biopterinas/metabolismo , Genótipo , Humanos , Recém-Nascido , Fenilalanina/administração & dosagem , Fenilalanina Hidroxilase/deficiência , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/sangue , Fenilcetonúrias/dietoterapia , Fenilcetonúrias/enzimologia , Fenilcetonúrias/genética
6.
J Med Chem ; 49(21): 6264-72, 2006 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-17034132

RESUMO

The impact of species-dependent differences between human and rat MAO B on inhibitor screening was evidenced for two classes of compounds, coumarin and 5H-indeno[1,2-c]pyridazin-5-one derivatives. All examined compounds have shown a greater inhibitor potency toward human MAO B than toward rat MAO B. Moreover, no correlation was found between human and rat pIC(50) values. These divergences have important implications for the design and development of drugs involved in the MAO B metabolic pathway, suggesting that results obtained using rat enzyme cannot be extrapolated to human CNS, a priori. Indeed, the selection of a hit compound for lead generation could be different using human rather than rat enzyme. Moreover, the influence of substituents on the in vitro inhibition of human MAO B was markedly different between homogeneous series of coumarin and 5H-indeno[1,2-c]pyridazin-5-one derivatives, suggesting different binding modes, a hypothesis clearly supported by molecular docking simulations of inhibitors into the active site of human MAO B.


Assuntos
Cumarínicos/síntese química , Indenos/síntese química , Inibidores da Monoaminoxidase/síntese química , Monoaminoxidase/metabolismo , Piridazinas/síntese química , Animais , Sítios de Ligação , Cumarínicos/química , Cumarínicos/farmacologia , Desenho de Fármacos , Humanos , Técnicas In Vitro , Indenos/química , Indenos/farmacologia , Ligantes , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/enzimologia , Modelos Moleculares , Estrutura Molecular , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Ligação Proteica , Piridazinas/química , Piridazinas/farmacologia , Ratos , Especificidade da Espécie , Relação Estrutura-Atividade
7.
Chem Biol Drug Des ; 84(2): 206-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24612747

RESUMO

Tyrosinases are type 3 copper proteins involved in melanin biosynthesis, responsible for skin and hair color in mammals. To steer tyrosinase inhibitor discovery for therapeutic and cosmetic purposes, structural information about human tyrosinase is necessary. As this protein has never been crystallized so far, we derived a robust homology model built using structural information from Streptomyces castaneoglobisporus and Ipomea batata catecholoxidase enzymes. The active site containing two copper atoms in co-ordination with six histidine residues was refined through an optimization protocol based on molecular mechanics parameters for copper co-ordination and charges calculated by quantum mechanics methods. Five structural water molecules and a hydroxyl ion were found to be essential for optimization. The superimposition of the human homology model on crystallographic structures of tyrosinases from other species revealed similar overall backbone topologies, active site conformations, and conserved water molecules. Phenylthiourea (PTU), the tyrosinase inhibitor of reference, was then docked into the solvated human active pocket. A binding mode consistent with crystallographic information was obtained. Taken together, these findings demonstrated that the human tyrosinase model, deposited in the Protein Model Database, is a reliable structure for future rational inhibitor design projects.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Feniltioureia/farmacologia , Sequência de Aminoácidos , Domínio Catalítico , Humanos , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Monofenol Mono-Oxigenase/química , Alinhamento de Sequência , Homologia Estrutural de Proteína
8.
J Hepatol ; 48(3): 517-22, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18207281

RESUMO

Classical galactosemia is an autosomal recessive disorder caused by a deficiency of the enzyme galactose-1-phosphate uridyltransferase. Undoubtedly, some of the short term complications are linked to the toxic effects of the accumulated abnormal metabolites (galactose-1-phosphate and galactitol). However, the physiopathology of neonatal liver failure remains unclear. We report the case of a 7-week-old girl who was first diagnosed with liver failure, hypoprotidaemia, ascites and generalized edemas. High citrulline (293 micromol/L), on initial plasma amino acid, suggested the diagnosis of citrin deficiency. As the citric acid cycle intermediates were non-detectable (oxoglutarate, succinate and citrate), a cataplerotic state was suspected. As a result, citrate (as an anaplerotic treatment) induced a clear improvement in her liver function. Four weeks later, this patient was switched to a galactose-free formula (as recommended in citrin deficiency with galactosemia) and her pathological status returned to normal. Citrin deficiency was later ruled out by molecular biology studies; then we reintroduced a galactose-containing formula which re-evoked rapidly vomiting, galactose aversion and hepatic cytolysis and the diagnosis of classical galactosemia was established. Our case clearly shows that cataplerosis could play a role in the pathophysiology of the neonatal liver disease observed in classical galactosemia.


Assuntos
Proteínas de Ligação ao Cálcio/deficiência , Ciclo do Ácido Cítrico/fisiologia , Galactosemias/diagnóstico , Transportadores de Ânions Orgânicos/deficiência , Proteínas de Ligação ao Cálcio/metabolismo , Feminino , Galactosemias/complicações , Galactosemias/metabolismo , Humanos , Lactente , Hepatopatias/etiologia , Hepatopatias/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , UTP-Hexose-1-Fosfato Uridililtransferase/metabolismo
9.
Bioorg Med Chem ; 13(22): 6212-7, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16054369

RESUMO

Interest in inhibitors of monoamine oxidase type B (MAO B) has grown in recent years, due to their therapeutic potential in aging-related neurodegenerative diseases, such as Parkinson's disease and Alzheimer's disease. This study is devoted to the use of human recombinant MAO B obtained from a Baculovirus expression system (Supersomes MAO B, BD Gentest, MA, USA) as reliable and efficient enzyme source for MAO B inhibitor screening. Comparison of inhibition potencies (pIC50 values) determined with human cloned and human platelet MAO B for the two series of MAO B inhibitors, coumarin and 5H-indeno[1,2-c]pyridazin-5-one derivatives, showed that the difference between pIC50 values obtained with the two enzyme sources was not significant (P>0.05, Student's t-test). Hence, recombinant enzyme is validated as convenient enzyme source for MAO B inhibitor screening.


Assuntos
Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/efeitos dos fármacos , Monoaminoxidase/genética , Proteínas Recombinantes/genética , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Cumarínicos/análise , Cumarínicos/química , Cumarínicos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Concentração Inibidora 50 , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/análise , Inibidores da Monoaminoxidase/química , Piridazinas/análise , Piridazinas/classificação , Piridazinas/farmacologia
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