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1.
J Proteome Res ; 23(7): 2619-2628, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38910295

RESUMO

Chromatography-mass spectrometry-based lipidomics represents an essential tool for elucidating lipid dysfunction mechanisms and is extensively employed in investigating disease mechanisms and identifying biomarkers. However, the detection of low-abundance lipids in biological matrices, along with cumbersome operational procedures, complicates comprehensive lipidomic analyses, necessitating the development of highly sensitive, environmentally friendly, and automated methods. In this study, an online phase transition trapping-supercritical fluid extraction-chromatography-mass spectrometry (PTT-SFEC-MS/MS) method was developed and successfully applied to plasma lipidomics analysis in Type 1 diabetes (T1D) rats. The PTT strategy captured entire extracts at the column head by converting CO2 from a supercritical state to a gaseous state, thereby preventing peak spreading, enhancing peak shape for precise quantification, and boosting sensitivity without any sample loss. This method utilized only 5 µL of plasma and accomplished sample extraction, separation, and detection within 27 min. Ultimately, 77 differential lipids were identified, including glycerophospholipids, sphingolipids, and glycerolipids, in T1D rat plasma. The results indicated that the progression of the disease might be linked to alterations in glycerophospholipid and sphingolipid metabolism. Our findings demonstrated a green, highly efficient, and automated method for the lipidomics analysis of biological samples, providing a scientific foundation for understanding the pathogenesis and diagnosis of T1D.


Assuntos
Cromatografia com Fluido Supercrítico , Diabetes Mellitus Tipo 1 , Lipidômica , Espectrometria de Massas em Tandem , Animais , Lipidômica/métodos , Espectrometria de Massas em Tandem/métodos , Ratos , Cromatografia com Fluido Supercrítico/métodos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/metabolismo , Lipídeos/sangue , Lipídeos/química , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Masculino , Ratos Sprague-Dawley , Transição de Fase , Biomarcadores/sangue , Esfingolipídeos/sangue , Esfingolipídeos/análise , Esfingolipídeos/isolamento & purificação
2.
J Org Chem ; 87(13): 8599-8610, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704791

RESUMO

An iron-promoted oxidative tandem alkylation/cyclization of ynones with 4-alkyl-substituted 1,4-dihydropyridines for the efficient synthesis of 2-alkylated indenones is described. The process occurs via oxidative homolysis of a C-C σ-bond in 1,4-dihydropyridines to generate an alkyl radical followed by the addition of C-C triple bonds in ynones and intramolecular cyclization. A wide range of alkyl radicals could be efficiently transferred to generate a series of synthetically useful 2-alkylated indenones with excellent selectivity under mild conditions.


Assuntos
Di-Hidropiridinas , Alquilação , Ciclização , Di-Hidropiridinas/química , Ferro/química , Estresse Oxidativo
3.
Org Biomol Chem ; 20(18): 3767-3778, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35438126

RESUMO

Nitrogen heterocycles, especially polycyclic compounds, are significant skeletons in valuable molecules. Herein, we developed an efficient and practical visible-light-induced acylation/cyclization of active alkenes with acyl oxime derivatives for constructing acylated indolo/benzimidazo-[2,1,a]isoquinolin-6(5H) ones. This reaction was compatible with various functional groups and a series of fused indole/imidazole skeletons were prepared in up to 95% yield at room temperature.


Assuntos
Alcenos , Compostos Policíclicos , Acilação , Ciclização , Luz
4.
J Asthma ; 58(12): 1555-1564, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32985283

RESUMO

OBJECTIVE: We conducted a cross-sectional study to investigate the associations between domestic pets and respiratory health in children. METHODS: We randomly recruited 11,611 school children from Zhongshan, a southern city in China. Information about the respiratory symptoms and disease history of the recruited children, the status of domestic pets, and other related risk factors were collected from March to July 2016. RESULTS: We identified cat-keeping at home increases the risk of persistent cough (OR, 1.77; 95%CI, 1.03-3.05); poultry-keeping at home increases the risk of current asthma (OR, 3.87; 95%CI, 1.08-13.92) and allergic rhinitis (OR, 1.84; 95%CI, 1.01-3.37); sleeping with pets increases the risk of persistent phlegm (OR, 5.04; 95%CI, 1.05-24.28), doctor-diagnosed asthma (OR, 3.35; 95%CI, 1.31-8.57) and current asthma (OR, 4.94; 95%CI, 1.05-23.31) in children. CONCLUSIONS: Cat-keeping and molds on the wall of the house had the multiplicative and additive interaction in doctor-diagnosed asthma. In conclusion, pet-keeping increased the risk of respiratory symptoms in children.


Assuntos
Asma/epidemiologia , Animais de Estimação , Adolescente , Fatores Etários , Animais , Gatos , Galinhas , Criança , Pré-Escolar , China/epidemiologia , Tosse/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Rinite Alérgica/epidemiologia , Autorrelato , Sono , Fatores Sociodemográficos
5.
J Alzheimers Dis Rep ; 8(1): 129-142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38312529

RESUMO

Background: Alzheimer's disease (AD) is a genetically intricate neurodegenerative disorder. Studies on "Ferroptosis in AD", "Pyroptosis in AD", and "Necroptosis in AD" are becoming more prevalent and there is increasing evidence that they are closely related to AD. However, there has not yet been a thorough bibliometrics-based investigation on this subject. Objective: This study uses a bibliometric approach to visualize and analyze the literature within the field of three distinct types of cell death in AD and explores the current research hotspots and prospective research directions. Methods: We collected relevant articles from the Web of Science and used CiteSpace, VOS viewer, and Pajek to perform a visual analysis. Results: A total of 123, 95, and 84 articles were published in "Ferroptosis in AD", "Pyroptosis in AD", and "Necroptosis in AD", respectively. Based on keywords analysis, we can observe that "oxidative stress" and "lipid peroxidation", "cell death" and "activation", and "Nlrp3 inflammasome" and "activation" were the three most prominent words in the field of "Ferroptosis in AD", "Pyroptosis in AD", and "Necroptosis in AD", respectively. Focusing on the breakout words in the keyword analysis, we reviewed the mechanisms of ferroptosis, pyroptosis, and necroptosis in AD. By mapping the time zones of the keywords, we speculated on the evolutionary trends of ferroptosis, pyrotosis, and necroptosis in AD. Conclusions: Our findings can help researchers grasp the research status of three types of cell death in AD and determine new directions for future research as soon as possible.

6.
J Colloid Interface Sci ; 650(Pt A): 857-864, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37450974

RESUMO

Bi2Se3 is a promising material for anodes in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) due to its abundance, easy preparation, and high capacity. However, its practical application is hindered by low conductivity and significant volume variation during cycling, leading to poor rate capability and cycling stability. Herein, a novel composite consisting of Bi2Se3 nanoplates deposited on carbon cloth (CC) and encapsulated by reduced graphene oxide (rGO) has been designed and synthesized. The composite structure combines the advantages of the Bi2Se3 nanoplates, CC substrate, and rGO encapsulation, leading to enhanced electrochemical properties. The physical vapor deposition of Bi2Se3 nanoplates onto CC ensures a high loading of active material, while the rGO encapsulation provides a conductive and stable framework for the composite. This synergistic design allows for improved electron and ion transport, as well as efficient accommodation of the volume changes during cycling. In LIBs, the composite demonstrates a high reversible capacity of 467.5 mAh/g at 0.1 A/g after 120 cycles. Moreover, it displays an outstanding rate capability, delivering a capacity of 398.6 mAh/g at 5.0 A/g. Similarly, in SIBs, the composite maintains a reversible capacity of 375.3 mAh/g at 0.1 A/g over 100 cycles and exhibits a high-rate capacity of 286.3 mAh/g at 5.0 A/g. This work represents a significant step forward in addressing the challenges associated with Bi2Se3 as an anode material, paving the way for the development of high-performance LIBs and SIBs.

7.
Anal Chim Acta ; 1279: 341831, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827647

RESUMO

BACKGROUND: Developing an environmentally friendly and efficient integrated analytical approach is a cutting-edge topic in current analytical science. Due to the unique properties of supercritical carbon dioxide (sc-CO2), online supercritical fluid extraction-supercritical fluid chromatography (SFE-SFC) is developing rapidly and has been widely applied in many fields. However, it still faces several challenges such as peak broadening and matrix interference. In order to solve the problems, we developed an inline phase transition trapping-selective supercritical fluid extraction-supercritical fluid chromatography (PTT-SSFE-SFC)-tandem mass spectrometry (MS/MS) method in this study. RESULTS: This method integrated extraction, purification, separation, and detection, which was applied to determine 114 prohibited substances in cosmetics within 33 min, covering ten categories. The PTT strategy trapped the extracts on the head of the column by transforming CO2 from a supercritical state to a gaseous state, preventing peak spreading and improving sensitivity. Several adsorbents were tested when analyzing aqueous samples to reduce matrix interference and absorb water. Compared with conventional online SFE-SFC, this method improved the matrix effects of 93 and 87 target substances in the toner and mask matrix, respectively. Because the integrated method reduced sample loss, it achieved high sensitivity with LODs ranging from 0.00104 µg L-1 to 3.09 µg L-1. Furthermore, compared with other reported green methods, the inline method showed advantages in automation, efficiency, sample amount, and waste volume. SIGNIFICANCE AND NOVELTY: With the introduction of the PTT strategy and the adsorbent, the system obtained good peak shapes, high sensitivity, low matrix effect, and good recovery. Based on the results, inline PTT-SSFE-SFC-MS/MS as a green and efficient integrated method has great potential for analyzing low abundance and multiple categories of targets in complex samples.


Assuntos
Cromatografia com Fluido Supercrítico , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia com Fluido Supercrítico/métodos , Dióxido de Carbono , Limite de Detecção , Água
8.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 2): o375, 2009 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-21581973

RESUMO

The title compound, C(19)H(17)ClN(2)O(5)S, was synthesized by the reaction of ethyl 6-(4-chloro-phen-yl)-2-mercapto-4-methyl-1,6-dihydro-pyrimidine-5-carboxyl-ate and dimethyl acetyl-ene-dicarboxyl-ate in methanol. In the mol-ecule, the nearly planar thia-zole ring, with a mean deviation from the plane of 0.0108 (3) Å, is fused with a dihydro-pyrimidine ring in a flattened half-chair conformation.

9.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 2): o398, 2009 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21581991

RESUMO

In the title compound, C(30)H(30)N(4)O(7)S, the two spiro junctions link a planar 2-oxindole ring [with a mean deviation from the plane of 0.0319 (3) Å, a pyrrolidine ring in an envelope conformation and a thia-zolo[3,2-a]pyrimidine system. Two mol-ecules are connected into a dimer by two N-H⋯O hydrogen bonds, forming an R(2) (2)(8) graph-set motif. The title compound has four stereogenic centers and appears as a racemic mixture of one single diastereoisomer (RSRR/SRSS).

10.
ACS Appl Mater Interfaces ; 10(32): 27047-27055, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30049207

RESUMO

Biomass with abundant resources and low price is regarded as potential sources of functionalized carbon-based energy storage and conversion electrode materials. Rational construction and development of biomass-derived carbon equipped with proper morphology, structure, and composition prove the key to highly efficient utilization of advanced energy storage systems. Herein, we use palm tree bark hair as a biomass source and prepare edge/defect-rich quasi-mesoporous carbon (QMC) by a direct pyrolysis followed by NaOH etching strategy. Then, the edge-rich quasi-mesoporous nitrogen-doped carbon (QMNC) is successfully fabricated through the hydrothermal method by making use of edge/defect-rich QMC and urea as carbon precursor and nitrogen source, respectively. The microstructure and composition of the resultant carbon materials are all detected by a series of techniques. In the meantime, the influence of the etching process on the preparation and electrochemical performance of edge-rich QMNC is systematically explored. The relevant results manifest that the as-prepared edge/defect-rich QMC not only possesses edge-rich plane, much increased specific surface area (SSA), and special quasi-mesopores but also reverses good conductivity and gains sufficient defects for subsequent N doping. After introducing N atoms, the obtained edge-rich QMNC exhibits outstanding capacitive property and oxygen reduction reaction performance, which are mainly attributed to the co-effect of edge-rich plane, large SSA, suitable pore structures, and effective N doping (including high doping amount and optimized N configurations). Clearly, our work not only offers an excellent biomass-derived carbon-based electrode material but also opens a fresh avenue for the development of advanced biomass-derived carbon-based electrode materials.


Assuntos
Casca de Planta , Biomassa , Carbono , Técnicas Eletroquímicas , Nitrogênio , Phoeniceae , Porosidade
11.
ACS Appl Mater Interfaces ; 10(1): 704-712, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29243910

RESUMO

ZnS coated on N,S co-doped carbon (ZnS/NSC) composite has been prepared utilizing zinc pyrithione (C10H8N2O2S2Zn) as raw material via calcination. Through activation using Na2CO3 salt, ZnS nanoparticles encapsulated in NSC (denoted as A-ZnS/NSC) with mixed-crystal structure has also been obtained, which reveals much larger specific surface area and more bridges between ZnS and NSC. Based on the existence of bridges (C-S-Zn and S-O-Zn bonds) and the modification of carbon from N,S co-doping, the A-ZnS/NSC composite as an anode for sodium-ion batteries (SIBs) displays significantly enhanced electrochemical performances with a high reversible specific capacity of 516.6 mA h g-1 (at 100 mA g-1), outstanding cycling stability (96.9% capacity retention after 100 cycles at 100 mA g-1), and high rate behavior (364.9 mA h g-1 even at 800 mA g-1).

12.
Artigo em Inglês | MEDLINE | ID: mdl-21684199

RESUMO

Fluorescence and ultraviolet spectroscopy were used to explore the interaction between thiazolopyrimidines (TAPM) and bovine serum albumin (BSA) under imitated physiological conditions. The experimental results show that thiazolopyrimidines can quench the fluorescence of BSA through a static quenching process. The binding constants, binding sites, and thermodynamic parameters at different temperatures were calculated. The calculated results indicate that the interaction between thiazolopyrimidines and BSA is driven mainly by Van der Waals' force and hydrogen bonds. The binding distances r was obtained based on Förster theory of non-radiation energy transfer. The comparison of binding potency of thiazolopyrimidines and BSA suggests that the substituent on the benzene ring promotes the binding process of thiazolopyrimidines and BSA.


Assuntos
Pirimidinas/metabolismo , Soroalbumina Bovina/metabolismo , Tiazóis/metabolismo , Animais , Bovinos , Modelos Moleculares , Estrutura Molecular , Pirimidinas/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Tiazóis/química
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