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1.
Calcif Tissue Int ; 112(4): 512-517, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36656330

RESUMO

Although vitamin D deficiency resulting from insufficient sunlight exposure or inadequate dietary vitamin D intake is the most common cause of rickets, mutations in genes involved in vitamin D metabolism can cause genetic forms of rickets termed Vitamin D-Dependent Rickets (VDDR). In 2018, Roizen et al. described a new type of VDDR, named VDDR3, caused by a recurrent missense mutation in the CYP3A4 gene that leads to accelerated inactivation of vitamin D metabolites. Here, we describe the third case of VDDR3 due to the same CYP3A4 mutation in a 2-year-old boy with bone deformities associated with poor growth. As in the previously reported cases, this patient had no family history of rickets. Serial measurements of vitamin D metabolites after a single 150,000 IU dose of cholecalciferol demonstrated an accelerated inactivation of 25(OH)D and 1,25(OH)2D. Significant improvement in growth velocity and healing of bone deformities were achieved after a short period of treatment with 10.000 IU of cholecalciferol daily, showing the importance of early recognition and prompt precision therapy of this condition.


Assuntos
Raquitismo , Deficiência de Vitamina D , Pré-Escolar , Humanos , Masculino , Colecalciferol , Citocromo P-450 CYP3A/uso terapêutico , Raquitismo/tratamento farmacológico , Raquitismo/genética , Vitamina D/metabolismo , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico
2.
J Am Soc Mass Spectrom ; 33(3): 573-583, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35157449

RESUMO

When investigating the potential use of plants as a raw material for an all-natural cosmetic formulation, the main parameters are the chemical composition, antioxidant potential, antimicrobial action, and toxicity. Additionally, the production of natural cosmetics should also consider the availability of primary materials and the environmental and socioeconomic impact. Gliricidia sepium is a species that produces a large amount of plant material, being cultivated in the agroforestry system. However, studies of phytochemical composition and chemical spatial distribution are scarcely using the MALDI MS (matrix-assisted laser desorption ionization mass spectrometry) and MALDI MSI (mass spectrometry imaging) techniques. A methodology was developed to optimize ionization parameters and analysis conditions by evaluating the efficiency of three matrices: α-cyano-4-hydroxycinnamic acid, 2,5-dihydroxybenzoic acid (DHB), and 2-mercaptobenzothiazole in MALDI MS analysis. All results were compared to ESI MS (electrospray ionization mass spectrometry), and afterward, MALDI MSI analysis was performed on the leaf surface. This study showed through phytochemical analysis that G. sepium leaves are composed of polyphenols and tannins, concluding that the methanolic extract had a higher amount of flavonoid content. Four compounds were identified on the leaf surface, and their spatial distribution was analyzed by MALDI MS using DHB as a matrix. Kaempferol, isorhamnetin, and some fatty acids showed potential applicability for cosmetical use. All the extracts presented antioxidant activity or antimicrobial action and no cytotoxicity. Therefore, extracts of G. sepium could be used as raw materials in cosmetics.


Assuntos
Fabaceae/química , Imagem Molecular/métodos , Compostos Fitoquímicos , Folhas de Planta/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cosméticos , Camundongos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Compostos Fitoquímicos/toxicidade , Polifenóis/análise , Polifenóis/química , Polifenóis/toxicidade
3.
J Am Soc Mass Spectrom ; 32(4): 946-955, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33715356

RESUMO

Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) can determine the chemical identity and spatial distribution of several molecules in a single analysis, conserving its natural histology. However, there are no specific studies on the spatial distribution of alkaloids in Erythroxylum coca leaves by MALDI IMS, preserving the histology of the monitored compounds. Therefore, in this work, positive-ion mode MALDI Fourier-transform ion cyclotron resonance imaging mass spectrometry (MALDI(+)FT-ICR IMS) was applied to identify and analyze the distribution of alkaloids on the surface of coca leaves, evaluating the ionization efficiency of three matrices (α-cyano-4-hydroxycinnamic acid (CHCA), 2-mercaptobenzothiazole (MBT), and 2,5-dihydroxybenzoic acid (DHB)). The last was chosen as the best matrix in this study, and it was studied in five concentrations (0.5, 1.0, 2.0, 4.0, and 8.0 mg·mL-1), where 2 mg·mL-1 was the most efficient. The washing of coca leaves with the organic solvents (acetonitrile, methanol, toluene, and dichloromethane) tested did not improve the performance of the ionization process. Finally, a tissue section, 50 µm thick, was used to study the inner part of the leaf tissue, where alkaloids and flavonoid molecules were detected.


Assuntos
Alcaloides/análise , Coca/química , Folhas de Planta/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Benzotiazóis/análise , Ácidos Cumáricos/análise , Ciclotrons , Gentisatos/análise , Espectroscopia de Infravermelho com Transformada de Fourier
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