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1.
Molecules ; 29(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474666

RESUMO

Micro/nanomotors represent a burgeoning field of research featuring small devices capable of autonomous movement in liquid environments through catalytic reactions and/or external stimuli. This review delves into recent advancements in light-driven semiconductor-based micro/nanomotors (LDSM), focusing on optimized syntheses, enhanced motion mechanisms, and emerging applications in the environmental and biomedical domains. The survey commences with a theoretical introduction to micromotors and their propulsion mechanisms, followed by an exploration of commonly studied LDSM, emphasizing their advantages. Critical properties affecting propulsion, such as surface features, morphology, and size, are presented alongside discussions on external conditions related to light sources and intensity, which are crucial for optimizing the propulsion speed. Each property is accompanied by a theoretical background and conclusions drawn up to 2018. The review further investigates recent adaptations of LDSM, uncovering underlying mechanisms and associated benefits. A brief discussion is included on potential synergistic effects between different external conditions, aiming to enhance efficiency-a relatively underexplored topic. In conclusion, the review outlines emerging applications in biomedicine and environmental monitoring/remediation resulting from recent LDSM research, highlighting the growing significance of this field. The comprehensive exploration of LDSM advancements provides valuable insights for researchers and practitioners seeking to leverage these innovative micro/nanomotors in diverse applications.

2.
Molecules ; 27(23)2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36500600

RESUMO

The possibility of generating organically modified hollow TiO2 microspheres via a simple sol-gel synthesis was demonstrated for the first time in this work. A mixture of titania precursors, including an organically modified precursor, was used to obtain methyl-modified hollow TiO2 microspheres selective for bilirubin by the molecular imprinting technique (Methyl-HTM-MIM). Methyl-HTM-MIM were prepared by a sol-gel method using titanium (IV) isopropoxide (TTIP), and methyltitanium triisopropoxide (MTTIP) as precursors. Two ratios of titania precursors were tested (1/6 and 1/30 molMTTIP/molTTIP). With the characterization results obtained by the SEM and ATR-FTIR techniques, it was possible to establish that only the 1/30 molMTTIP/molTTIP ratio allowed for the preparation of hollow spheres with a reasonably homogeneous methylated-TiO2 shell. It was possible to obtain a certain degree of organization of the hybrid network, which increased with calcination temperatures. By adjusting isothermal adsorption models, imprinting parameters were determined, indicating that the new methylated microspheres presented greater selectivity for bilirubin than the totally inorganic hollow TiO2 microspheres. The effectiveness of the molecular imprinting technique was proven for the first time in an organically modified titania material, with imprinting factor values greater than 1.4, corresponding to a significant increase in the maximum adsorption capacity of the template represented by the molecularly imprinted microspheres. In summary, the results obtained with the new methyl-HTM-MIM open the possibility of exploring the application of these microspheres for selective sorption (separation or sensing, for example) or perhaps even for selective photocatalysis, particularly for the degradation of organic compounds.


Assuntos
Impressão Molecular , Impressão Molecular/métodos , Microesferas , Titânio , Adsorção
3.
J Mol Recognit ; 31(3)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28156029

RESUMO

Imprinting chondroitin sulfate (CS)/silica composites with Pb(II) and Cu(II) cations was explored with CS of bovine and different fish species origin. The process was based on the assumption that particular arrangements of the linear CS chains in aqueous solution, induced so as to accommodate cross complexation with the cations, would be embodied into a tridimensional matrix created through an organoalkoxysilane sol-gel scheme. The presence of Cu(II) in the synthesis of the composites did not result in the production of significantly stronger Cu(II)-oriented binding arrangements, and therefore, the imprinting was not successful. Inversely, for Pb(II), the materials obtained exhibited a "memory" effect for the Pb(II) ions, expressed in the observation of stronger (13%-44%) binding as compared to the nonimprinted counterparts, and increased selectivity (1.5-2 folds) against Cd(II). The imprinting features observed were dependent on the CS source. However, it was not possible to identify, among a set of their properties (carboxylate and sulfate abundance, percent of disulfated units, 4S/6S ratio, and molecular weight), any that correlated directly with the observed imprinting features. The augmented selectivity provided by the cation-imprinting process may be advantageous in areas such as analytical separation, remediation, purification, sensing, and others, particularly in those cases where a certain cation is of special interest within a mixture of them.


Assuntos
Sulfatos de Condroitina/química , Chumbo/química , Impressão Molecular , Animais , Cátions/química , Bovinos , Peixes
4.
Arq Neuropsiquiatr ; 74(1): 62-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26690837

RESUMO

OBJECTIVE: To verify if nighttime feeding habits can influence parasomnia in children. METHOD: Seven private and four public Elementary Schools took part in the study. A total of 595 Sleep Disturbance Scale for Children were distributed to the parents of children aged from 7 to 8 years. Data of dietary recall, starting time to school, physical activity, and nutritional status were studied. RESULTS: Of the 226 questionnaires completed, 92 (41%) reported parasomnia. Girls had 2.3 times more the chance to parasomnia than boys. Children who consumed stimulant foods had 2.6 times more chance to have parasomnia than those of children who consumed non-stimulant foods. There were no difference between parasomnia and no-parasomnia groups in food type (p = 0.78) or timing of last meal before bedtime (p = 0.50). CONCLUSION: Our findings suggest that intake of stimulant foods is associated with development of parasomnia in children.


Assuntos
Cafeína/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Comportamento Alimentar/fisiologia , Alimentos/efeitos adversos , Refeições/fisiologia , Parassonias/etiologia , Parassonias/metabolismo , Índice de Massa Corporal , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Estado Nutricional/fisiologia , Parassonias/epidemiologia , Prevalência , Fatores Sexuais , Inquéritos e Questionários
5.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;74(1): 62-66, Jan. 2016. tab
Artigo em Inglês | LILACS | ID: lil-772606

RESUMO

ABSTRACT Objective To verify if nighttime feeding habits can influence parasomnia in children. Method Seven private and four public Elementary Schools took part in the study. A total of 595 Sleep Disturbance Scale for Children were distributed to the parents of children aged from 7 to 8 years. Data of dietary recall, starting time to school, physical activity, and nutritional status were studied. Results Of the 226 questionnaires completed, 92 (41%) reported parasomnia. Girls had 2.3 times more the chance to parasomnia than boys. Children who consumed stimulant foods had 2.6 times more chance to have parasomnia than those of children who consumed non-stimulant foods. There were no difference between parasomnia and no-parasomnia groups in food type (p = 0.78) or timing of last meal before bedtime (p = 0.50). Conclusion Our findings suggest that intake of stimulant foods is associated with development of parasomnia in children.


RESUMO Objetivo Verificar se hábitos de alimentação noturna influenciam parassonias em crianças. Método Sete escolas privadas e quatro públicas, de Ensino Fundamental, fizeram parte do estudo. Um total de 595 Escalas de Distúrbio do Sono para Crianças foram distribuídas para os pais de crianças entre 7 e 8 anos. Dados de recordatório alimentar, período escolar, atividade física e estado nutricional foram estudados. Resultados Dos 226 questionários preenchidos, 92 (41%) relataram presença de parassonias. Meninas tiveram 2,3 vezes mais chance de parassonias e crianças que consumiram alimentos estimulantes tiveram 2,6 vezes mais chance de parassonias em relação àquelas que consumiram alimentos não estimulantes. Não houve diferença entre os grupos em relação ao tipo de alimento (p = 0,78) ou horário da última refeição antes de ir para a cama (p = 0,50). Conclusão Nossos achados sugerem que a ingestão de alimentos estimulantes está associada com o desenvolvimento de parassonias em crianças.


Assuntos
Criança , Feminino , Humanos , Masculino , Cafeína/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Comportamento Alimentar/fisiologia , Alimentos/efeitos adversos , Refeições/fisiologia , Parassonias/etiologia , Parassonias/metabolismo , Índice de Massa Corporal , Estudos Transversais , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estado Nutricional/fisiologia , Prevalência , Parassonias/epidemiologia , Fatores Sexuais , Inquéritos e Questionários
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