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1.
Dev Neurorehabil ; 24(4): 244-255, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33355029

RESUMO

Purpose: To describe the development of the Cognition domain of the Hong Kong Comprehensive Assessment Scales for Toddlers (HKCAS-T).Methods: Participants included 345 toddlers aged 18-41 months, with 258 recruited from Maternal and Child Health Centers (MCHCs) and 87 with cognitive delay recruited from Child Assessment Centers (CACs). They were individually administered the 83-item pilot version by medical practitioners or educational psychologists between 2017 and 2019 in MCHCs and CACs in Hong Kong.Results: Rasch analysis results supported the unidimensionality of the pilot version, after removing six items. Analysis of covariance results indicated that both the 83-item version and the 77-item version could differentiate between children of different age groups, and children with typical development from children with cognitive delay. Internal consistency and interrater reliability were 0.90 or above.Conclusions: The Cognition domain of the HKCAS-T is a promising developmental assessment tool for the assessment of toddlers. Cognition assessment, preschool, Chinese.


Assuntos
Desenvolvimento Infantil , Cognição , Testes Neuropsicológicos/normas , Pré-Escolar , Feminino , Humanos , Masculino , Psicometria/normas , Reprodutibilidade dos Testes
2.
PLoS One ; 14(3): e0213591, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30856213

RESUMO

To investigate limiters of photosynthate assimilation in the carbon-source limited crop, oil palm (Elaeis guineensis Jacq.), we measured differential metabolite, gene expression and the gas exchange in leaves in an open field for palms with distinct mesocarp oil content. We observed higher concentrations of glucose 1-phosphate, glucose 6-phosphate, sucrose 6-phosphate, and sucrose in high-oil content palms with the greatest difference being at 11:00 (p-value ≤0.05) immediately after the period of low morning light intensity. Three important photosynthetic genes were identified using differentially expressed gene analysis (DEGs) and were found to be significantly enriched through Gene Ontology (GO) and pathway enrichment: chlorophyll a-b binding protein (CAB-13), photosystem I (PSI), and Ferredoxin-NADP reductase (FNR), particularly for sampling points at non-peak light (11:00 and 19:00), ranging from 3.3-fold (PSI) and 5.6-fold (FNR) to 10.3-fold (CAB-13). Subsequent gas exchange measurements further supported increased carbon assimilation through higher level of internal CO2 concentration (Ci), stomatal conductance (gs) and transpiration rate (E) in high-oil content palms. The selection for higher expression of key photosynthesis genes together with CO2 assimilation under low light is likely to be important for crop improvement, in particular at full maturity and under high density planting regimes where light competition exists between palms.


Assuntos
Arecaceae/genética , Óleo de Palmeira/metabolismo , Folhas de Planta/genética , Proteínas de Plantas/genética , Arecaceae/metabolismo , Dióxido de Carbono/metabolismo , Ritmo Circadiano , Regulação da Expressão Gênica de Plantas , Fotossíntese , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo
3.
J Agric Food Chem ; 66(4): 999-1007, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29260544

RESUMO

During high-temperature refining of vegetable oils, 3-monochloropropanediol (3-MCPD) esters, possible carcinogens, are formed from acylglycerol in the presence of a chlorine source. To investigate organochlorine compounds in vegetable oils as possible precursors for 3-MCPD esters, we tested crude palm, soybean, rapeseed, sunflower, corn, coconut, and olive oils for the presence of organochlorine compounds. Having found them in all vegetable oils tested, we focused subsequent study on oil palm products. Analysis of the chlorine isotope mass pattern exhibited in high-resolution mass spectrometry enabled organochlorine compound identification in crude palm oils as constituents of wax esters, fatty acid, diacylglycerols, and sphingolipids, which are produced endogenously in oil palm mesocarp throughout ripening. Analysis of thermal decomposition and changes during refining suggested that these naturally present organochlorine compounds in palm oils and perhaps in other vegetable oils are precursors of 3-MCPD esters. Enrichment and dose-response showed a linear relationship to 3-MCPD ester formation and indicated that the sphingolipid-based organochlorine compounds are the most active precursors of 3-MCPD esters.


Assuntos
Hidrocarbonetos Clorados/química , Óleos de Plantas/química , alfa-Cloridrina/química , Carcinógenos , Cloro/química , Ésteres/química , Contaminação de Alimentos , Manipulação de Alimentos , Glicerídeos/química , Óleo de Palmeira/química , alfa-Cloridrina/análise , alfa-Cloridrina/síntese química
4.
PLoS One ; 11(6): e0156714, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27258536

RESUMO

Interest in the medicinal properties of secondary metabolites of Boesenbergia rotunda (fingerroot ginger) has led to investigations into tissue culture of this plant. In this study, we profiled its primary and secondary metabolites, as well as hormones of embryogenic and non-embryogenic (dry and watery) callus and shoot base, Ultra Performance Liquid Chromatography-Mass Spectrometry together with histological characterization. Metabolite profiling showed relatively higher levels of glutamine, arginine and lysine in embryogenic callus than in dry and watery calli, while shoot base tissue showed an intermediate level of primary metabolites. For the five secondary metabolites analyzed (ie. panduratin, pinocembrin, pinostrobin, cardamonin and alpinetin), shoot base had the highest concentrations, followed by watery, dry and embryogenic calli. Furthermore, intracellular auxin levels were found to decrease from dry to watery calli, followed by shoot base and finally embryogenic calli. Our morphological observations showed the presence of fibrils on the cell surface of embryogenic callus while diphenylboric acid 2-aminoethylester staining indicated the presence of flavonoids in both dry and embryogenic calli. Periodic acid-Schiff staining showed that shoot base and dry and embryogenic calli contained starch reserves while none were found in watery callus. This study identified several primary metabolites that could be used as markers of embryogenic cells in B. rotunda, while secondary metabolite analysis indicated that biosynthesis pathways of these important metabolites may not be active in callus and embryogenic tissue.


Assuntos
Aminoácidos/química , Zingiber officinale/embriologia , Zingiber officinale/metabolismo , Compostos de Boro/química , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Ésteres/química , Ácidos Indolacéticos/química , Espectrometria de Massas , Metaboloma , Brotos de Planta/metabolismo , Análise de Componente Principal , Técnicas de Cultura de Tecidos
5.
J Agric Food Chem ; 62(32): 8143-52, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25032485

RESUMO

Oil palm is one of the most productive oil-producing crops and can store up to 90% oil in its fruit mesocarp. Oil palm fruit is a sessile drupe consisting of a fleshy mesocarp from which palm oil is extracted. Biochemical changes in the mesocarp cell walls, polyamines, and hormones at different ripening stages of oil palm fruits were studied, and the relationship between the structural and the biochemical metabolism of oil palm fruits during ripening is discussed. Time-course analysis of the changes in expression of polyamines, hormones, and cell-wall-related genes and metabolites provided insights into the complex processes and interactions involved in fruit development. Overall, a strong reduction in auxin-responsive gene expression was observed from 18 to 22 weeks after pollination. High polyamine concentrations coincided with fruit enlargement during lipid accumulation and latter stages of maturation. The trend of abscisic acid (ABA) concentration was concordant with GA4 but opposite to the GA3 profile such that as ABA levels increase the resulting elevated ABA/GA3 ratio clearly coincides with maturation. Polygalacturonase, expansin, and actin gene expressions were also observed to increase during fruit maturation. The identification of the master regulators of these coordinated processes may allow screening for oil palm variants with altered ripening profiles.


Assuntos
Arecaceae/metabolismo , Parede Celular/metabolismo , Produtos Agrícolas/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/biossíntese , Poliaminas/metabolismo , Ácido Abscísico/metabolismo , Actinas/genética , Actinas/metabolismo , Arecaceae/crescimento & desenvolvimento , Parede Celular/enzimologia , Produtos Agrícolas/enzimologia , Produtos Agrícolas/crescimento & desenvolvimento , Cruzamentos Genéticos , Frutas/crescimento & desenvolvimento , Giberelinas/genética , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Metabolismo dos Lipídeos , Malásia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polinização , Poligalacturonase/genética , Poligalacturonase/metabolismo , RNA Mensageiro/metabolismo , RNA de Plantas/metabolismo , Regulação para Cima
6.
PLoS One ; 8(4): e61344, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23593468

RESUMO

To better understand lipid biosynthesis in oil palm mesocarp, in particular the differences in gene regulation leading to and including de novo fatty acid biosynthesis, a multi-platform metabolomics technology was used to profile mesocarp metabolites during six critical stages of fruit development in comparatively high- and low-yielding oil palm populations. Significantly higher amino acid levels preceding lipid biosynthesis and nucleosides during lipid biosynthesis were observed in a higher yielding commercial palm population. Levels of metabolites involved in glycolysis revealed interesting divergence of flux towards glycerol-3-phosphate, while carbon utilization differences in the TCA cycle were proven by an increase in malic acid/citric acid ratio. Apart from insights into the regulation of enhanced lipid production in oil palm, these results provide potentially useful metabolite yield markers and genes of interest for use in breeding programmes.


Assuntos
Arecaceae/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Lipídeos/biossíntese , Aminoácidos/metabolismo , Arecaceae/genética , Biomarcadores/metabolismo , Cruzamento/métodos , Cromatografia Líquida , Ácido Cítrico/metabolismo , Frutas/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Malatos/metabolismo , Metabolômica/métodos , Análise de Componente Principal
7.
J Agric Food Chem ; 61(8): 1920-7, 2013 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23384169

RESUMO

Oil palm is one of the most productive oil producing crops and can store up to 90% oil in its fruit mesocarp. However, the biosynthetic regulation and drivers of palm mesocarp development are still not well understood. Multiplatform metabolomics technology was used to profile palm metabolites during six critical stages of fruit development in order to better understand lipid biosynthesis. Significantly higher amino acid levels were observed in palm mesocarp preceding lipid biosynthesis. Nucleosides were found to be in high concentration during lipid biosynthesis, whereas levels of metabolites involved in the tricarboxylic acid cycle were more concentrated during early fruit development. Apart from insights into the regulation of metabolites during fruit development in oil palm, these results provide potentially useful metabolite yield markers and genes of interest for use in breeding programs.


Assuntos
Arecaceae/crescimento & desenvolvimento , Arecaceae/metabolismo , Frutas/metabolismo , Óleos de Plantas/química , Arecaceae/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/crescimento & desenvolvimento , Espectrometria de Massas , Metabolômica , Óleo de Palmeira , Óleos de Plantas/metabolismo
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