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1.
Environ Sci Pollut Res Int ; 31(13): 19674-19686, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38363509

RESUMO

Evidence around the relationship between air pollution and the development of diabetes mellitus (DM) remains limited and inconsistent. To investigate the potential mediation effect of asprosin on the association between fine particulate matter (PM2.5), tropospheric ozone (O3) and blood glucose homeostasis. A case-control study was conducted on a total of 320 individuals aged over 60 years, including both diabetic and non-diabetic individuals, from six communities in Taiyuan, China, from July to September 2021. Generalized linear models (GLMs) suggested that short-term exposure to PM2.5 was associated with elevated fasting blood glucose (FBG), insulin resistance index (HOMA-IR), as well as reduced pancreatic ß-cell function index (HOMA-ß), and short-term exposure to O3 was associated with increased FBG and decreased HOMA-ß in the total population and elderly diabetic patients. Mediation analysis showed that asprosin played a mediating role in the relationship of PM2.5 and O3 with FBG, with mediating ratios of 10.2% and 18.4%, respectively. Our study provides emerging evidence supporting that asprosin mediates the short-term effects of exposure to PM2.5 and O3 on elevated FBG levels in an elderly population. Additionally, the elderly who are diabetic, over 70 years, and BMI over 24 kg/m2 are more vulnerable to air pollutants and need additional protection to reduce their exposure to air pollution.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Diabetes Mellitus , Fibrilina-1 , Idoso , Humanos , Pessoa de Meia-Idade , Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Glicemia/metabolismo , Estudos de Casos e Controles , China/epidemiologia , Diabetes Mellitus/metabolismo , Exposição Ambiental/análise , Material Particulado/análise , Fibrilina-1/metabolismo , Adipocinas/metabolismo
2.
ACS Appl Mater Interfaces ; 12(30): 33795-33802, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32628446

RESUMO

Single-atom catalysts (SACs) with atomically dispersed metal sites in nitrogen-doped carbon matrices (M-N/C) have been identified as promising candidates for the electrocatalytic CO2 reduction reaction (CO2RR). However, recent studies aiming at economic viability have been inhibited by the low faradaic efficiency (FE) and instability under high current density. Herein, we report a series of SACs derived from cyano-substituted metal phthalocyanines (MePc-CN) in ZIFs (denoted as Me-SACs (Pc)). These phthalocyanine molecules enable the efficient construction of SACs, affording higher metal loading and less variation when compared with their counterparts from metal nitrates (denoted as Me-SACs (S)). Thus, Me-SACs (Pc) exhibit higher activities and selectivities than Me-SACs (S) in H-cell measurements. In gas-diffusion electrode (GDE) setups, the unstable Fe-SAC (Pc) shows only a 50% FE of CO (FEco) at -100 mA cm-2. In contrast, Ni-SAC (Pc) exhibits a higher FEco of >96% at current densities from -10 to -200 mA cm-2 and can stably operate for over 16 h at -200 mA cm-2. The performances of Ni-SAC (Pc) are comparable to those of precious metal catalysts and the best SACs reported so far, representing a promising candidate for practical electrolyzer devices for CO2RR.

3.
Molecules ; 24(15)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366111

RESUMO

Rheum palmatum L. (R. palmatum L.) is a traditional Chinese herb and food, in which rhein and emodin are the main bioactive components. The extraction of the two compounds from R. palmatum L. is, thus, of great importance. In this work, protic ionic liquids (PILs) were applied in the microwave-assisted extraction (MAE) of rhein and emodin from R. palmatum L., which avoids the toxicity of organic solvents. The results of the present study indicate that PILs possessing higher polarity exhibit higher extraction ability due to their stronger absorption ability for microwave irradiation. Compared with conventional solvents, such as methanol, trichloromethane, and deep eutectic solvents (DESs), the PIL, 1-butyl-3-himidazolium methanesulfonate ([BHim]MeSO3) reported herein is more efficient. The selected extraction conditions of liquid-solid ratio, microwave irradiation time, microwave irradiation power, and PIL concentration were 40 g·g-1, 50 s, 280 W, and 80%, respectively. Under the selected conditions, the extraction yields of rhein and emodin were 7.8 and 4.0 mg·g-1, respectively. These results suggest that PILs are efficient extraction solvents for the separation of active components from natural products.


Assuntos
Antraquinonas/isolamento & purificação , Emodina/isolamento & purificação , Imidazóis/química , Líquidos Iônicos/química , Extração Líquido-Líquido/métodos , Mesilatos/química , Rheum/química , Cromatografia Líquida de Alta Pressão , Análise Fatorial , Humanos , Micro-Ondas , Extratos Vegetais/química , Solventes/química
4.
J Nat Prod ; 71(11): 1938-41, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18959443

RESUMO

The first total synthesis of bulbophylol-B (1) has been achieved with the longest linear sequence of 12 steps and an overall yield of 17.9% via a new and practical approach to construct the dihydrodibenz[b,f]oxepin skeleton employing Wittig, selective reduction, and intramolecular Ullmann reactions as key steps.


Assuntos
Benzoxepinas/síntese química , Benzoxepinas/química , Ciclização , Estrutura Molecular , Estereoisomerismo
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