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1.
Environ Geochem Health ; 46(9): 319, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012521

RESUMO

Pneumoconiosis is the most common occupational disease among coal miners, which is a lung disease caused by long-term inhalation of coal dust and retention in the lungs. The early stage of this disease is highly insidious, and pulmonary fibrosis may occur in the middle and late stages, leading to an increase in patient pain index and mortality rate. Currently, there is a lack of effective treatment methods. The pathogenesis of pneumoconiosis is complex and has many influencing factors. Although the characteristics of coal dust have been considered the main cause of different mechanisms of pneumoconiosis, the effects of coal dust composition, particle size and shape, and coal dust concentration on the pathogenesis of pneumoconiosis have not been systematically elucidated. Meanwhile, considering the irreversibility of pneumoconiosis progression, early prediction for pneumoconiosis patients is particularly important. However, there is no early prediction standard for pneumoconiosis among coal miners. This review summarizes the relevant research on the pathogenesis and prediction of pneumoconiosis in coal miners in recent years. Firstly, the pathogenesis of coal worker pneumoconiosis and silicosis was discussed, and the impact of coal dust characteristics on pneumoconiosis was analyzed. Then, the early diagnostic methods for pneumoconiosis have been systematically introduced, with a focus on image collaborative computer-aided diagnosis analysis and biomarker detection. Finally, the challenge of early screening technology for miners with pneumoconiosis was proposed.


Assuntos
Minas de Carvão , Poeira , Humanos , Pneumoconiose , Antracose/epidemiologia , Exposição Ocupacional/efeitos adversos , Biomarcadores , Carvão Mineral , Doenças Profissionais/etiologia , Doenças Profissionais/epidemiologia
2.
Acc Chem Res ; 55(18): 2545-2561, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36083117

RESUMO

Enantiopure atropisomers have become increasingly important in asymmetric synthesis and catalysis, pharmaceutical science, and material science since the discovery of inherent features of axial chirality originating from rotational restriction. Despite the advances made in this field to date, it remains highly desirable to construct structurally diverse atropisomers with potentially useful functions. We propose superposition to match axial and point chirality as a potentially useful strategy to access structurally complex and diverse building blocks for organic synthesis and pharmaceutical science because merging atropisomeric backbones with one or more extra chiral elements can topologically broaden three-dimensional environments to create complex scaffolds with multiple tunable parameters. Over the past decade, we have successfully implemented a strategic design for the superposition of axial and point chirality to develop a series of enantiopure atropisomers and have utilized the synergistic functions of these molecules to enhance chirality transfer in various catalytic asymmetric transformations.In this Account, we present several novel atropisomers with superposed axial and point chirality developed in our laboratory. In our studies, this superposition strategy was used to design and synthesize both biaryl and non-biaryl atropisomers from commercially available chiral sources. Consequently, these atropisomers were used to demonstrate the importance of the synergetic functions of axial and point chirality in specific enantioselective reactions. For example, aromatic amide-derived atropisomers, simplified as Xing-Phos arrays, were broadly employed in Ag-catalyzed [3 + 2] cycloaddition by a series of reactions of aldiminoesters with activated alkenes and imines, as well as being used as chiral solvating agents for the discrimination of optically active mandelic acid derivatives. Considering the powerful potential of non-biaryl atropisomers for asymmetric catalysis, we also explored the transition-metal-catalyzed enantioselective construction of a novel backbone of non-biaryl atropisomers (Ar-alkene, Ar-N axis) bearing both axial and point chirality for the design and synthesis of chiral ligands and functional molecules.The studies presented herein are expected to stimulate further research efforts on the development of functional atropisomers by superposition of matching axial and point chirality. In addition to tunable electron and stereohindrance effects, the synergy between matching chiral elements of axial/point chirality and functional groups is proven to be a special function that cannot be ignored for promoting reactivity and chirality-transfer efficiency in enantioselective synthesis. Consequently, our novel types of scaffolds with superposed axial and point chirality that are capable of versatile coordination with various metal catalysts in asymmetric catalysis highlight the power of the superposition of matching axial and point chirality for the construction of synthetically useful atropisomers.


Assuntos
Alcenos , Iminas , Amidas , Preparações Farmacêuticas , Estereoisomerismo
3.
Soft Matter ; 19(47): 9315-9324, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38013463

RESUMO

In this work, gelatin was dissolved in sodium acetate trihydrate/urea deep eutectic solvent (DES) and then mixed with polyacrylonitrile (PAN) spinning solution to prepare composite nanofiber membranes via electrospinning. The rheological properties of gelatin/DES (Gel/DES) solution and gelatin/DES/PAN (GDES/PAN) spinning solution were investigated. Besides, the water vapor transmittance rate, water contact angle, and antistatic and mechanical properties of GDES/PAN nanofiber membranes had also been evaluated and the composition and structure of GDES/PAN nanofiber membranes had also been characterized by SEM, EDS and FTIR further. Due to the introduction of DES components and gelatin, the composite nanofibers presented a smooth surface, small diameter, uniform distribution and good continuity. GDES/PAN nanofiber membranes also exhibited desirable breathable properties, hydrophilicity, antistatic properties and mechanical strength compared with the PAN nanofiber membrane. GDES/PAN nanofiber membranes would provide new opportunities for the application of gelatin and DES in the electrospinning field.

4.
Soft Matter ; 18(17): 3278-3290, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35437550

RESUMO

Human disorders associated with amyloid aggregation, such as Alzheimer's disease and Parkinson's disease, afflict the lives of millions worldwide. When peptides and proteins in the body are converted to amyloids, which have a tendency to aggregate, the toxic oligomers produced during the aggregation process can trigger a range of diseases. Nanoparticles (NPs) have been found to possess surface effects that can modulate the amyloid aggregation process and they have potential application value in the treatment of diseases related to amyloid aggregation and fibrillary tangles. In this review, we discuss recent progress relating to studies of nanoparticles that regulate amyloid aggregation. The review focuses on the factors influencing this regulation, which are important as guidelines for the future design of NPs for the treatment of amyloid aggregation. We describe the characterization methods that have been utilized so far in such studies. This review provides research information and characterization methods for the rational design of NPs, which should result in therapeutic strategies for amyloid diseases.


Assuntos
Doença de Alzheimer , Nanopartículas , Doença de Alzheimer/metabolismo , Amiloide/química , Peptídeos beta-Amiloides , Humanos , Nanopartículas/química , Peptídeos
5.
J Org Chem ; 87(19): 13346-13351, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36129738

RESUMO

An iridium-catalyzed, directing group-enabled site selective intra- and intermolecular silylation of indoles and pyrroles with hydrosilanes has been developed under ligand-free conditions. Fine-tuning of the removable 3-alkyl-2-pyridyl directing group was found to be crucial for achieving high yields for C2-silylated indole and pyrrole products. Moreover, the scalability was demonstrated, and further transformations of the silylation products were achieved.

6.
Angew Chem Int Ed Engl ; 61(46): e202211922, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36165575

RESUMO

Although palladium-catalyzed asymmetric C-H functionalization and Heck reactions represents one of the most important synthetic strategies for the construction of quaternary stereocenters, developing the enantioselective version of PdII -catalyzed carbopalladation-initiated cascade reactions still remains a formidable challenge. Herein, an unprecedent enantioselective [3+2] annulation of oxime ethers and alkynes has been developed, providing both spiro and nonspiro indenes bearing all-carbon quaternary stereocenters in good yields (up to 98 %) with excellent enantioselectivities (up to >99 % ee). This annulation is accomplished by merging the PdII -catalyzed atroposelective C-H activation/double carbopalladation and the transient axial-to-central chirality transfer process, constituting the first successful example of catalytic chirality transfer strategy involving axially chiral styrene intermediate.

7.
Chemistry ; 27(13): 4336-4340, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33481303

RESUMO

Although asymmetric C-H functionalization has been available for the synthesis of structurally diverse molecules, catalytic dynamic kinetic resolution (DKR) approaches to change racemic stereogenic axes remain synthetic challenges in this field. Here, a concise palladium-catalyzed DKR was combined with C-H functionalization involving olefination and alkynylation for the highly efficient synthesis of non-biaryl-atropisomer-type (NBA) axially chiral oragnosilanes. The chemistry proceeded through two different and distinct DKR: first, an atroposelective C-H olefination or alkynylation produced axially chiral vinylsilanes or alkynylsilanes as a new family of non-biaryl atropisomers (NBA), and second, the extension of this DKR strategy to twofold o,o'-C-H functionalization led to the multifunctional axially chiral organosilicon compounds with up to >99 % ee.

8.
Chemistry ; 23(17): 4055-4059, 2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28181312

RESUMO

Direct functionalization of terpyridines is an increasingly important topic in the field of dyes and catalysis as well as supramolecular chemistry, but its synthesis and transformation is usually challenging. Herein, a HOMO-raising strategy is reported for the construction of a super-stable novel terpyridine chromophores, in which the selective oxidation of terpyridines at its 3-position was determined successfully to the synthesis of phenol-functionalization of terpyridines (TPyOHs) bearing a hydrogen bonding group. The corresponding TPyOHs displayed strong aggregation-induced emission and exhibited highly selective and visual detection of ZnII cation with a record green terpyridine-based luminophore with nanomolar sensitivity (125 nm).

9.
Molecules ; 22(5)2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28524100

RESUMO

It was found that 1,2-trifluoromethylation reactions of ketones, enones, and aldehydes were easily accomplished using the Prakash reagent in the presence of catalytic amounts of cesium carbonate, which represents an experimentally convenient, atom-economic process for this anionic trifluoromethylation of non-enolisable aldehydes and ketones.


Assuntos
Carbonatos/química , Césio/química , Chalconas/química , Éteres/síntese química , Cetonas/química , Silanos/síntese química , Aldeídos/química , Catálise , Técnicas de Química Sintética , Halogenação , Metilação , Estrutura Molecular , Estereoisomerismo
10.
Chemistry ; 22(30): 10399-404, 2016 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-27198615

RESUMO

The mechanism-oriented reaction design for the divergent synthesis of chiral molecules from simple starting materials is highly desirable. In this work, aromatic amide-derived nonbiarylatropisomer/silver (silver/Xing-Phos) complex was used to catalyze the Michael addition of glycine aldimino esters to chalcones and successfully applied to the subsequent cyclocondensation to afford substituted cis-Δ(1)-pyrroline derivatives with up to 98 % ee. Besides the inherent performance of the chiral Ag/Xing-Phos catalyst system, it was found that the workup of such reactions played an important role for the stereoselective construction of stereodivergent Δ(1)-pyrrolines, in which an epimerization of the cis-Δ(1)-pyrrolines to the trans-isomers during was revealed.

11.
Org Biomol Chem ; 14(2): 564-569, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26511901

RESUMO

A regio- and stereoselective synthesis of highly substituted α-haloenamides was described via the zinc halide mediated direct addition of benzhydryl halides to ynamides under mild conditions. The products α-haloenamides were further transformed into multisubstituted enamides via Suzuki and Sonogashira cross-coupling reactions.

12.
Org Biomol Chem ; 14(33): 7927-32, 2016 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-27488387

RESUMO

It was found that the tridentate O,N,O-type Schiff base ligand bearing suitable substituents was a highly effective promoter in the catalytic asymmetric bromochlorination reaction, in which the corresponding aromatic bromochloroalcohols with vicinal halogen-bearing stereocenters were formed with perfect regioselectivity, with moderate to excellent enantioselectivities (up to 93% ee), and with good yields and chemoselectivities.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38683945

RESUMO

At present, the preparation of laser-induced graphene (LIG) has become an important technology in sensor manufacturing. In the conventional preparation process, the CO2 laser is widely used; however, its experimental period is long and its efficiency needs to be improved. We propose an innovative strategy to improve the experimental efficiency. We use the machine learning method to accurately predict the preparation parameters of LIG, so as to optimize the experimental process. Different structures can lead to different sensor performances. The structure constructed by the CO2 laser is rough and has a large size, which can affect the performance of the sensor. Therefore, we propose for the first time an innovative method for intramembrane structure construction that combines the advantages of the CO2 laser and fiber laser (CF-L). With this CF-L method, we have successfully prepared a biomimetic, flexible strain sensor. This sensor not only maintains a high degree of sensitivity, but also has a more refined and optimized structure. The manufacturing process of the whole sensor is simple, economical, and durable and can be prepared in large quantities and can be used to detect the extension and bending of human joints.

14.
J Colloid Interface Sci ; 666: 540-546, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613976

RESUMO

Na3V2(PO4)3 is considered as one of the most promising cathodes for sodium ion batteries owing to its fast Na+ diffusion, good structural stability and high working potential. However, its practical application is limited by its low intrinsic electronic conductivity. Herein, a carbon coated Cu2+-doped Na3V2(PO4)3 cathode was prepared. The carbon coating not only improve its apparent conductivity, but also inhibit crystal growth and prevent agglomeration of particles. Moreover, Cu2+ doping contributes to an enhanced intrinsic conductivity and decreased Na+ diffusion energy barrier, remarkably boosting its charge transfer kinetics. Based on the structure characterizations, electrochemical performances tests, charge transfer kinetics analyses and theoretical calculations, it's proved that such an elaborate design ensures the excellent rate performances (116.9 mA h g-1 at 0.1C; 92.6 mA h g-1 at 10C) and distinguished cycling lifespan (95.8 % retention after 300 cycles at 1C; 84.8 % retention after 3300 cycles at 10C). Besides, a two-phase reaction mechanism is also confirmed via in-situ XRD. This research is expected to promote the development of Na3V2(PO4)3-based sodium ion batteries with high energy/power density and excellent cycling lifespan.

15.
ISA Trans ; 139: 621-634, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37142491

RESUMO

The automatic positioning of underground mobile applications plays a crucial role in enabling intelligent coal mining. However, due to the diverse kinematics and dynamics of these applications, various positioning methods have been proposed to match different targets. Nonetheless, the accuracy and applicability of these methods still fall short of meeting the requirements for field applications. Based on the vibration characteristics of underground mobile devices, a multi-sensor fusion positioning system is developed to enhance the accuracy of positioning in long and narrow global positioning system denied (GPS-denied) underground coal mine roadways. The system combines inertial navigation (INS), odometer, and ultra wide band (UWB) technologies through extended Kalman filter (EKF) and unscented Kalman filter (UKF). This approach enables accurate positioning by recognizing target carrier vibrations and facilitating fast conversion between multi-sensor fusion modes. The proposed system is tested on both a small unmanned mine vehicle (UMV) and a large roadheader, demonstrating that UKF enhances stability for roadheaders with strong nonlinear vibrations while EKF is more suitable for flexible UMVs. Detailed results confirm that the proposed system achieves an accuracy level of 0.15 m, meeting most coal mine application requirements.

16.
Org Biomol Chem ; 10(48): 9556-61, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23117193

RESUMO

An efficient palladium-catalyzed method is reported for the synthesis of multi-substituted allenamides by Suzuki-Miyaura cross-coupling reaction between easily prepared 3-alkoxycarbonyloxy ynamides or 1-alkoxycarbonyloxy allenamides and arylboronic acids.

17.
Wei Sheng Wu Xue Bao ; 52(9): 1122-8, 2012 Sep 04.
Artigo em Chinês | MEDLINE | ID: mdl-23236846

RESUMO

OBJECTIVE: To identify the interaction between influenza A virus PB1-F2 and human modulator of apoptosis 1 (MOAP-1). METHODS: The recombinant plasmid pACT2-MOAP-1 was constructed and co-transformed into yeast AH109 with pGBKT7-PB1-F2. The growth of the co-transformants on quadruple dropout medium and beta-galactosidase activity of the reporter gene were tested. We further confirmed the interaction of cellular protein MOAP-1 and PB1-F2 by glutathione S-transferase (GST) pull-down and co-immunoprecipitation (Co-IP) assays. In addition, we investigated the effect of PB1-F2 on MOAP-1 protein level by Western blot. RESULTS: The results of yeast two-hybrid assay showed that MOAP-1 specifically interacted with PB1-F2 in yeast cells. Furthermore, the binding of MOAP-1 with PB1-F2 was demonstrated by glutathione S-transferase pull-down and Co-IP assays. PB1-F2 could upregulate exogenous MOAP-1 protein level. CONCLUSION: These results suggested that influenza virus PB1-F2 interacted with MOAP-1 and it might be involved in the regulation of cell growth and apoptosis via association with MOAP-1.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Vírus da Influenza A Subtipo H1N1/metabolismo , Influenza Humana/metabolismo , Proteínas Virais/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/genética , Ligação Proteica , Técnicas do Sistema de Duplo-Híbrido , Proteínas Virais/genética
18.
Front Psychol ; 13: 901497, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35756220

RESUMO

Mental toughness is an essential component of adolescent athletes' athletic careers and lives. Evidence supports the positive effect of belief in a just world on individual psychological development, but the relationship between belief in a just world and mental toughness of adolescents has not been tested. In order to determine the influencing factors of mental toughness and explore effective strategies for improving adolescent athletes' mental toughness, this study introduced just world and life meaning theories to explore the relationship between belief in a just world, meaning in life (search for meaning/presence of meaning), and mental toughness. Based on the data of 1,544 adolescent athletes from Yantai and Qingdao in Shandong Province, China, we tested a parallel mediation model that considered the search for meaning and presence of meaning as mediators. The results were predicted as follows: there is a significant positive correlation between belief in a just world and mental toughness, while the relationship between belief in a just world and mental toughness was partially mediated by the search for meaning and the presence of meaning in life. Furthermore, it is worth noting that the presence of meaning played a more influential role than the search for meaning. The results suggest that belief in a just world is connected to the mental toughness of adolescent athletes via the meaning in life. Therefore, maintaining and promoting the level of belief in a just world and enhancing the sense of meaning in life may be an effective strategy to develop the mental toughness of adolescent athletes. The findings of this study can help develop the mental toughness of adolescent athletes and help them maintain a high level of subjective and objective performance under the pressure of training and competition, providing practical guidance for coaches and administrators in the training of adolescent athletes.

19.
Mater Sci Eng C Mater Biol Appl ; 109: 110553, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228980

RESUMO

A green strategy by integrating surface-initiated metal-free photoinduced electron transfer-atom transfer radical polymerization (PET-ATRP) with mussel-inspired polydopamine (PDA) chemistry, was used to fabricate multi-walled carbon nanotubes (MWCNTs)/poly(4-vinylpyridine) (P4VP) nanocomposites. Self-healing nanocomposite hydrogels were facilely designed with these nanocomposites through dynamic supramolecular interactions. Using mussel-inspired PDA chemistry from MWCNTs, nanocomposites (MWCNTs@PDA-P4VP) were successfully prepared by metal-free PET-ATRP with MWCNTs@PDA-Br as an initiator, rhodamine B as photocatalyst, 4-vinylpyridine (4VP) as monomer, respectively. Importantly, the obtained nanocomposite hydrogels had high mechanical strength (2.9 MPa), prior fracture strain (633.8%) and excellent self-healing property (90.6%). These methodologies will provide opportunities for the design of eco-functional materials or flexible biosensors.


Assuntos
Materiais Biomiméticos/química , Hidrogéis/química , Nanocompostos/química , Nanotubos de Carbono/química , Polivinil/química , Animais , Bivalves
20.
Chem Commun (Camb) ; 55(95): 14363-14366, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31720613

RESUMO

A unique 1,3-dipolar [3+2] cycloaddition of alkyl 4-oxo-4-arylbut-2-enoates bearing two different electron-withdrawing groups was completed by using the silver/(R)-DTBM-Segphos catalyst system, which gives the corresponding fully substituted pyrrolidines with four stereogenic centers in good yields and with excellent enantioselectivities (up to 98% ee).

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