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1.
Arch Endocrinol Metab ; 67(6): e000646, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37364148

RESUMO

Objective: Recent studies investigated the role of amino acids (AAs) in weight management. We aimed to determine the association between AAs and three-year change of anthropometric indices and incident obesity. Materials and methods: Height, weight, hip, and waist circumference (WC) were collected at baseline and follow up. Three-year changes in anthropometric indices and obesity incident according to body mass index (BMI) (overweight & obesity) and WC cutoffs (obesity-WC) were ascertained. Dietary intakes of AAs were collected at baseline, using a food frequency questionnaire. Data analyses were conducted on 4976 adult participants and two subsamples, including 1,570 and 2,918 subjects, for assessing the AAs relationship with 3-year changes on anthropometric indices and obesity incident. Results: Lysine and aspartic acid were positively associated with higher weight change, whereas acidic AAs, cysteine, and glutamic acid showed a negative correlation with weight change. Furthermore, a weak positive correlation was shown for alkaline AAs, lysine, and valine with WC; however, acidic AAs, tryptophan, cysteine, and glutamic acid were negatively associated with WC. Aromatic and acidic AAs also demonstrated a weak negative relation with changes in BAI. Phenylalanine and Aromatic AAs showed a negative association with overweight &obesity incidence adjusting for potential confounders. Each quartile increases the dietary lysine, arginine, alanine, methionine, aspartic acid, and alkaline AAs related to a greater risk of obesity-WC, while tryptophan, glutamic acid, proline, and acidic AAs associated with lower obesity-WC risk. Conclusion: Our results suggested that certain dietary AAs may potentially change anthropometric indices and risk of obesity incident.


Assuntos
Ácido Aspártico , Sobrepeso , Adulto , Humanos , Sobrepeso/epidemiologia , Triptofano , Cisteína , Lisina , Irã (Geográfico)/epidemiologia , Obesidade/epidemiologia , Obesidade/complicações , Índice de Massa Corporal , Circunferência da Cintura , Aminoácidos , Lipídeos , Glutamatos , Fatores de Risco
2.
Arch. endocrinol. metab. (Online) ; 67(6): e000646, Mar.-Apr. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447267

RESUMO

ABSTRACT Objective: Recent studies investigated the role of amino acids (AAs) in weight management. We aimed to determine the association between AAs and three-year change of anthropometric indices and incident obesity. Materials and methods: Height, weight, hip, and waist circumference (WC) were collected at baseline and follow up. Three-year changes in anthropometric indices and obesity incident according to body mass index (BMI) (overweight & obesity) and WC cutoffs (obesity-WC) were ascertained. Dietary intakes of AAs were collected at baseline, using a food frequency questionnaire. Data analyses were conducted on 4976 adult participants and two subsamples, including 1,570 and 2,918 subjects, for assessing the AAs relationship with 3-year changes on anthropometric indices and obesity incident. Results: Lysine and aspartic acid were positively associated with higher weight change, whereas acidic AAs, cysteine, and glutamic acid showed a negative correlation with weight change. Furthermore, a weak positive correlation was shown for alkaline AAs, lysine, and valine with WC; however, acidic AAs, tryptophan, cysteine, and glutamic acid were negatively associated with WC. Aromatic and acidic AAs also demonstrated a weak negative relation with changes in BAI. Phenylalanine and Aromatic AAs showed a negative association with overweight &obesity incidence adjusting for potential confounders. Each quartile increases the dietary lysine, arginine, alanine, methionine, aspartic acid, and alkaline AAs related to a greater risk of obesity-WC, while tryptophan, glutamic acid, proline, and acidic AAs associated with lower obesity-WC risk. Conclusion: Our results suggested that certain dietary AAs may potentially change anthropometric indices and risk of obesity incident.

3.
Front Psychol ; 12: 727794, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603150

RESUMO

The aim of this study was to investigate mediating roles of students' self-system processes and positive academic emotions in a relationship between supporting autonomy and agentic engagement. In This research structural equation modeling was used to analyze a conceptual model. The sample consisted of 452 undergraduate students of Ferdowsi University of Mashhad. The research instruments included the autonomy-supportive environment inventory, the self-system processes questionnaire, three questionnaires of academic emotions, and the agentic engagement scale. The findings showed that supporting autonomy had an indirect effect on students' achievement emotions, via self-system processes. Self-system processes had direct and indirect effects on agentic engagement, via positive academic emotions. Supporting autonomy had an indirect effect on agentic engagement by mediating role of self-system processes and positive academic emotions. Accordingly, emotions are proximal determinants of agentic engagement. Supporting autonomy and self-system processes affect agentic engagement from the pathway of academic emotions. Therefore, in addition to environmental factors and self-appraisals, it is necessary to consider students' emotional experiences to promote agentic engagement in learning settings.

4.
IET Nanobiotechnol ; 12(7): 939-945, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30247134

RESUMO

Silver nanoparticles (NPs) are immobilised on pistachio shell surface by Cichorium intybus L. leaves extract as an antioxidant media. The Fourier transform infrared spectra, X-ray diffraction, field-emission scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, and transmission electron microscope analyses confirmed the support of silver NPs on the pistachio shell (Ag NPs/pistachio shell). Ag NPs on the pistachio shell had a diameter basically in the 10-15 nm range. Reduction reactions of 4-nitrophenol (4-NP), and organic dyes at ambient condition were used in the investigation of the catalytic performance of the prepared catalyst. Through this research, the Ag NPs/pistachio shell shows a high activity and recyclability, and reusability without loss of its catalytic activity.


Assuntos
Asteraceae/química , Nanopartículas Metálicas/química , Pistacia/química , Extratos Vegetais/metabolismo , Prata/química , Química Verde , Nanocompostos/química , Nitrofenóis/análise , Nitrofenóis/química , Nitrofenóis/metabolismo , Oxirredução , Pistacia/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Sementes/química , Prata/metabolismo
5.
J Colloid Interface Sci ; 493: 85-93, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28088570

RESUMO

In this paper, silver nanoparticles (Ag NPs) are synthesized using Achillea millefolium L. extract as reducing and stabilizing agents and peach kernel shell as an environmentally benign support. FT-IR spectroscopy, UV-Vis spectroscopy, X-ray Diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy Dispersive X-ray Spectroscopy (EDS), Thermo gravimetric-differential thermal analysis (TG-DTA) and Transmission Electron Microscopy (TEM) were used to characterize peach kernel shell, Ag NPs, and Ag NPs/peach kernel shell. The catalytic activity of the Ag NPs/peach kernel shell was investigated for the reduction of 4-nitrophenol (4-NP), Methyl Orange (MO), and Methylene Blue (MB) at room temperature. Ag NPs/peach kernel shell was found to be a highly active catalyst. In addition, Ag NPs/peach kernel shell can be recovered and reused several times with no significant loss of its catalytic activity.


Assuntos
Achillea/química , Corantes/química , Química Verde , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prunus persica/química , Prata/química , Água/química , Catálise , Oxirredução , Reciclagem
6.
Environ Sci Pollut Res Int ; 24(4): 4093-4104, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27933496

RESUMO

Palladium nanoparticles (PdNPs) have been immobilized on the surface of walnut shell powder using Equisetum arvense L. leaf extract as reducing and stabilizing agents in this work. FT-IR spectroscopy, UV-Vis spectroscopy, photoluminescence spectroscopy, X-ray diffraction (XRD) pattern, field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM) have been used in the characterization of the nanocomposites thus prepared. High catalytic activity was shown by these nanocomposites in the reduction of different dyes. The PdNPs' diameter on the walnut shell was predominantly found within the 5-12-nm range. The advantages of these catalysts include facile and clean synthesis, simple preparation procedure, excellent properties, alterable supports, and low cost, which make them applicable in reduction of 4-nitrophenol (4-NP), Congo red (CR), methylene blue (MB), and rhodamine B (RhB) in the presence of aqueous NaBH4 at room temperature. Pd/walnut shell nanocomposites were highly active catalysts for reduction of these dyes. Moreover, Pd/walnut shell nanocomposite can be recovered and recycled seven times without any appreciable loss of catalytic activity. Graphical abstract Waste walnut shell as a natural valuable resource support for green synthesis of Pd/walnut shell nanocomposite using Equisetum arvense L. leaf extract and its application for the reduction of 4-nitrophenol and organic dyes in a very short time.


Assuntos
Equisetum/química , Juglans/química , Nanocompostos/química , Nitrofenóis/química , Paládio/química , Extratos Vegetais/química , Catálise , Azul de Metileno/química , Folhas de Planta/química
7.
J Colloid Interface Sci ; 490: 1-10, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27870949

RESUMO

For the first time the extract of the plant of Salvia hydrangea was used to green synthesis of Pd nanoparticles (NPs) supported on Apricot kernel shell as an environmentally benign support. The Pd NPs/Apricot kernel shell as an effective catalyst was prepared through reduction of Pd2+ ions using Salvia hydrangea extract as the reducing and capping agent and Pd NPs immobilization on Apricot kernel shell surface in the absence of any stabilizer or surfactant. According to FT-IR analysis, the hydroxyl groups of phenolics in Salvia hydrangea extract as bioreductant agents are directly responsible for the reduction of Pd2+ ions and formation of Pd NPs. The as-prepared catalyst was characterized by Fourier transform infrared (FT-IR) and UV-Vis spectroscopy, field emission scanning electron microscopy (FESEM) equipped with an energy dispersive X-ray spectroscopy (EDS), Elemental mapping, X-ray diffraction analysis (XRD) and transmittance electron microscopy (TEM). The synthesized catalyst was used in the reduction of 4-nitrophenol (4-NP), Methyl Orange (MO), Methylene Blue (MB), Rhodamine B (RhB), and Congo Red (CR) at room temperature. The Pd NPs/Apricot kernel shell showed excellent catalytic activity in the reduction of these organic dyes. In addition, it was found that Pd NPs/Apricot kernel shell can be recovered and reused several times without significant loss of catalytic activity.


Assuntos
Corantes/química , Química Verde/métodos , Nanopartículas Metálicas/química , Paládio/química , Prunus armeniaca/química , Salvia/química , Compostos Azo/química , Catálise , Vermelho Congo/química , Nanopartículas Metálicas/ultraestrutura , Azul de Metileno/química , Nanotecnologia/métodos , Nitrofenóis/química , Oxirredução , Extratos Vegetais/química , Rodaminas/química
8.
Luminescence ; 29(8): 1074-81, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24723462

RESUMO

We report the first detailed study of the characteristics of an octahydro-Schiff base derivative as a new luminophor in the peroxyoxalate chemiluminescence (POCL) system. The effect of reagents on this new POCL system was investigated. In addition, the response surface methodology was used for evaluating the relative significance of variables in this POCL system, establishing models and determining optimal conditions. The quenching effect of some cations and compounds such as Cu(2+), Fe(3+), Hg(2+), imidazole, histidine and cholesterol on an optimized POCL reaction were studied. The dynamic ranges were up to approximaterly 100 and 175 × 10(-6) M for Cu(2+) and cholesterol respectively. The detection limits were 3.3 × 10(-6) m and 2.58 × 10(-6) m for Cu(2+) and histidine, respectively. In all cases the relative standard deviations were 4-5% (n = 4).


Assuntos
Colesterol/química , Luminescência , Medições Luminescentes/métodos , Oxalatos/química , Aminoácidos/química , Cátions/análise , Cátions/química , Colesterol/análise , Cobre/química , Histidina/análise , Histidina/química , Imidazóis/análise , Imidazóis/química , Ferro/química , Limite de Detecção , Bases de Schiff/química , Sensibilidade e Especificidade
9.
Eur J Med Chem ; 70: 364-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24177363

RESUMO

Two Cu(II) complexes, [Cu2(µ-atr)(pydc)2(H2O)4]·5H2O (1) and [Cu(atr)(pydc) (H2O)]·H2O (2), with pyridine-2,6-dicarboxylic acid (H2pydc) and 3-amino-1H-1,2,4-triazole (atr), have been synthesized and characterized. The interaction ability of the both complexes with native calf thymus DNA (CT-DNA) has been monitored as a function of the metal complex-DNA molar ratio. UV-vis spectrophotometry, circular dichroism (CD), thermal denaturation studies, cyclic voltammetry (CV) and viscosity measurements. The intrinsic binding constants K(b) of complexes 1 and 2, with CT-DNA obtained from UV-vis absorption studies were 4.7 (±0. 1) × 10(4) and 9.5 (±0. 1) × 10(4) M(-1), respectively. Further investigation of interaction mode was performed using viscosity, cyclic voltammetry and T(m) of CT-DNA studies as well as CD study, indicating complexes bind to DNA via an intercalation mode.


Assuntos
Cobre/química , DNA/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Ácidos Picolínicos/química , Triazóis/química , Animais , Sítios de Ligação/efeitos dos fármacos , Bovinos , DNA/química , Relação Dose-Resposta a Droga , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Relação Estrutura-Atividade , Viscosidade
10.
Artigo em Inglês | MEDLINE | ID: mdl-15978863

RESUMO

1H NMR spectroscopy was used to investigate the stoichiometry and stability of the drug ketamine cation complexes with some crown ethers, such as 15-crown-5 (15C5), aza-15-crown-5 (A15C5), 18-crown-6 (18C6), aza-18-crown-6 (A18C6), diaza-18-crown-6 (DA18C6), dibenzyl-diaza-18-crown-6 (DBzDA18C6) and cryptant [2,2,2] (C222) in acetonitrile (AN), dimethylsulfoxide (DMSO) and methanol (MeOH) at 27 degrees C. In order to evaluate the formation constants of the ketamine cation complexes, the CH3 protons chemical shift (on the nitrogen atom of ketamine) was measured as function of ligand/ketamine mole ratio. The formation constant of resulting complexes were calculated by the computer fitting of chemical shift versus mole ratio data to appropriate equations. A significant chemical shift variation was not observed for 15C5 and 18C6. The stoichiometry of the mono aza and diaza ligands are 1:1 and 1:2 (ligand/ketamine), respectively. In all of the solvents studied, DA18C6 formed more stable complexes than other ligands. The solvent effect on the stability of these complexes is discussed.


Assuntos
Éteres de Coroa/química , Ketamina/química , Solventes/química , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Químicos , Prótons
11.
Bioorg Med Chem ; 13(6): 2253-62, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15727876

RESUMO

Proton NMR was used as a probe to study the interaction of the Tl(+) ion with 9-18-membered macromonocyclic tri-, tetra-, and hexaamines in dimethylformamide (DMF) solution. A study of proton chemical shift of ligands as a function of Tl(+) ion to ligand mole ratio revealed that the complexation reactions occur in a stepwise manner. Formation of a 1:1 complex is followed by the addition of a second complexant molecule to form a homo-sandwich complex for triazamacrocycle ligands and a mixed ligand complex in the case of hexamethylhexacyclen (HMHCY) and 1,4,7-triazacyclononane ([9]aneN(3)). The formation constants of resulting 1:1 and 1:2 (homo and mixed ligand sandwich) complexes in DMF solution were evaluated from computer fitting of the chemical shift-mole ratio data. The mixed ligand complexes may be more stable than the parent complex in which both ligands are the same. The influence of cavity size and substitution of methyl groups on nitrogen atoms of the macrocyclic ring the stability of the resulting complexes is discussed. The geometries of the tri- and tetraazamacrocycle ligands and their Tl(+) ion complexes were optimized by an ab initio method, and the calculated binding energies of resulting complexes were compared. Both the experimental and theoretical studies revealed that, in the presence of methyl groups, the stability of triazamacrocycle complexes with Tl(+) ion was decreased.


Assuntos
Íons/química , Compostos Macrocíclicos/química , Tálio/química , Dimetilformamida , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular
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