Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Biol Pharm Bull ; 47(9): 1511-1524, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39284735

RESUMO

Siweixizangmaoru decoction (SXD) is widely used as an anti-rheumatoid arthritis (RA) in Tibet, however, the specific anti-inflammatory mechanism of SXD is still unclear. This research attempts to examine the efficacy and possible mechanisms of SXD in treating RA. The primary chemical components of SXD were identified using UHPLC-Q-Exactive Orbitrap MS. We established a lipopolysaccharide (LPS)-induced RAW264.7 macrophage inflammatory injury model to explore the anti-inflammatory mechanism of SXD and validated it through in vivo experiments. According to our research in vitro as well as in vivo, SXD exhibits anti-inflammatory qualities. SXD can suppress nitric oxide (NO) and pro-inflammatory factor production in RAW264.7 cells activated by LPS. The mechanism underlying this effect might be connected to the janus tyrosine kinase 2-signal transducer and activator of transcription 3 (JAK2/STAT3) and nuclear factor-κB (NF-κB) signaling pathways. In vivo, SXD alleviates joint swelling, decreases the generation of inflammatory factors in the serum, lowers oxidative stress, and improves joint damage. In short, SXD improves joint degeneration and lowers symptoms associated with RA by regulating inflammation via the suppression of NF-κB and JAK2/STAT3 signaling pathway activation.


Assuntos
Anti-Inflamatórios , Artrite Experimental , Medicamentos de Ervas Chinesas , Janus Quinase 2 , NF-kappa B , Fator de Transcrição STAT3 , Transdução de Sinais , Animais , Janus Quinase 2/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Células RAW 264.7 , Camundongos , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Artrite Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Masculino , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ratos , Ratos Sprague-Dawley , Colágeno Tipo II/metabolismo , Lipopolissacarídeos , Óxido Nítrico/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Medicina Tradicional Tibetana/métodos
2.
Angew Chem Int Ed Engl ; : e202414089, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221861

RESUMO

The exploration of novel functionalized supramolecular coordination complexes (SCCs) can enable new applications in domains that include purification and sensing. In this study, employing a coordination-driven self-assembly strategy, we designed and prepared a series of benzochalcogenodiazole-based metallohelicates as high-efficiency charge transfer surface-enhanced Raman scattering (SERS) substrates, expanding the range of applications for these metallohelicates. Through structural modifications, including the substitution of single heteroatoms on ligands, replacement of coordinating metals, and alteration of ligand framework linkages, the Raman performance of these metallohelicates as substrates were systematically optimized. Notably, the SERS enhancement factors (EFs) of the metallohelicate-based SERS substrates were significantly enhanced to levels as high as 1.03 × 107, which rivals the EFs of noble metals devoid of "hot spots". Additionally, the underlying Raman enhancement mechanisms of these metallohelicates have been investigated through a combination of control experiments and theoretical calculations. This study not only demonstrates the utility of metallohelicates as SERS substrates but also offers insights and materials for the development of high-efficiency new charge transfer SERS substrates.

3.
J Org Chem ; 88(7): 4627-4632, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36951514

RESUMO

A one-pot catalytic asymmetric route to novel chiral quaternary-carbon-containing cyclobutanone-fused 4-aminoquinoline derivatives in good to high yields and enantioselectivities is described. This process consists of a chiral phosphoric acid-catalyzed desymmetric carbonyl-amine condensation of prochiral cyclobutane-1,3-diones with 2-halogenated anilines and a Pd-catalyzed coupling reaction of the chiral enaminone intermediates with isocyanides.

4.
Angew Chem Int Ed Engl ; 53(17): 4350-4, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24652597

RESUMO

A simple, new type of chiral sulfinamide monophosphines, the so-called Ming-Phos ligands, is reported; these ligands could be easily prepared from inexpensive and commercially available starting materials. The Ming-Phos ligands performed well in the enantioselective gold-catalyzed cycloaddition reaction of 2-(1-alkynyl)-alk-2-en-1-ones with nitrones. Both enantiomers of the products could be obtained in good yields and with excellent diastereo- and enantioselectivity through transformations that were catalyzed by gold complexes derived from two diastereomers of Ming-Phos ligand M5 (Ar=1-naphthyl).

5.
Artigo em Inglês | MEDLINE | ID: mdl-39289942

RESUMO

BACKGROUND: Rheumatoid Arthritis (RA) is a chronic autoimmune disease with a complex etiology. Siweixizangmaoru Decoction (SXD) has been used to treat RA in Tibet for a long history as a classic Tibetan medicine formula. However, the potential pharmacological mechanism has not been elucidated yet. AIMS: The aim of this study was to evaluate the efficacy and mechanism of action of SXD in the treatment of RA using network pharmacology and molecular docking analysis. METHOD: Network pharmacology was employed to identify the potential bioactive components and key targets of SXD for the treatment of RA. Molecular docking of key targets and potential compounds was conducted. High-performance liquid chromatography was performed to validate the predicted active components of SXD. We established a rat model of RA and evaluated the histopathology of each group of rats. In addition, the levels of inflammatory factors in serum and the expression levels of PI3K/AKT and MAPK pathway-related proteins in synovial tissue were detected. RESULTS: The results of network pharmacological analyses indicated that apigenin, rhamnolipids, kaempferol, quercetin, and naringenin are potential bioactive components of SXD for the treatment of rheumatoid arthritis and that their therapeutic effects may be related to the PI3K-Akt and MAPK pathways. The results of in vivo experiments show that SXD improved the arthritis index, significantly reduced joint swelling, and improved synovial inflammation and cartilage destruction. CONCLUSION: Network pharmacology, along with experimental validation, provided a useful approach for understanding the pharmacological mechanism of Siweixizangmaoru decoction in RA.

6.
Materials (Basel) ; 15(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36363225

RESUMO

Using eggshell powder (EP) to replace partial cement in cement-based materials can abate pollution caused by eggshell discard and cement production. In this paper, the surface property of EP and its influence on cement hydration were studied. Quartz powder (QP) and limestone powder (LP) were used as references. First, the chemical composition of EP was characterized. Then, the surface charge properties of these materials were analyzed using zeta potential measurement. The interactions between EP surface and Ca2+ were discussed based on the zeta potential test. Afterward, a scanning electron microscope (SEM) was applied to observe the morphology of hydrates on the surfaces of these materials. The results indicated that, although the compositions of EP and LP are similar, the surface charge properties are significantly different. This is likely due to the existence of organic matter on the surface of EP and the difference in the atomic structure. As shown from the zeta potential test, EP exhibits similar interaction with Ca2+ as QP. The interactions between EP surface and Ca2+ are much weaker than that between LP and Ca2+. These weak interactions lead to the growth of C-S-H on the surface of EP particles less than that of LP particles. The chemical reactivity of EP can be improved by using heat treatment, electrical oven, etc. This study will provide theoretical support for the better use of EP in cement-based materials.

7.
Nanomaterials (Basel) ; 12(7)2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35407318

RESUMO

Methods and materials that effectively remove heavy metals, such as lead and copper, from wastewater are urgently needed. In this study, steel slag, a low-cost byproduct of steel manufacturing, was utilized as a substrate material for carbon nanotube (CNT) growth by chemical vapor deposition (CVD) to produce a new kind of efficient and low-cost absorbent without any pretreatment. The synthesis parameters of the developed CNT-steel slag composite (SS@CNTs) were optimized, and its adsorption capacities for Pb(II) and Cu(II) were evaluated. The results showed that the optimal growth time, synthesis temperature and acetylene flow rate were 45 min, 600 °C and 200 sccm (standard cubic centimeter per minute), respectively. The SS@CNTs composite had a high adsorption capacity with a maximum removal amount of 427.26 mg·g-1 for Pb(II) and 132.79 mg·g-1 for Cu(II). The adsorption proceeded rapidly during the first 15 min of adsorption and reached equilibrium at approximately 90 min. The adsorption processes were in accordance with the isotherms of the Langmuir model and the pseudo-second-order model, while the adsorption thermodynamics results indicated that the removal for both metals was an endothermic and spontaneous process. This study showed that compared with other adsorbent materials, the SS@CNTs composite is an efficient and low-cost adsorbent for heavy metals such as lead and copper.

8.
Materials (Basel) ; 16(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36614633

RESUMO

This study investigated the fatigue crack propagation behavior of ultra-high-performance concrete (UHPC) incorporated with different steel fiber lengths of 6, 13, and 20 mm under flexural cyclic loading, based on the Paris law and nonlinear fracture mechanics. In addition, multiple crack covering areas and fatigue J-integral amplitudes were employed to quantitatively evaluate the fatigue crack propagation rate and predicate the fatigue life of the UHPC during the steady development stage. The results indicated that the maximum crack opening displacement (COD) values were 0.312, 0.673, and 1.265 mm and the minimum crack growth rates were -3.05, -4.48 and -4.62 for SF6, SF13, and SF20, respectively. The critical crack length was approximately 65 mm for UHPC specimens containing different fiber length at a given fiber volume fraction (2.0%), indicating that the critical crack length was simply related to the fiber length. Interestingly, when the fatigue crack area of all the tested series reached approximately 35 mm2, fracture failure occurred. There were very small predictions between the actual tested and predicated fatigue lives, all less than 7.21%. Hence, it was reasonable to predict the fatigue life of the UHPC based on the J-integral according to the DIC technique.

9.
Materials (Basel) ; 14(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443220

RESUMO

By optimizing the distribution of steel fibers in fiber-reinforced cementitious mortar (FRCM) through the layered structure, the role of fibers can be fully utilized, thus improving the flexural behavior. In this study, the flexural behavior of layered FRCM at different thicknesses (25 mm, 50 mm, 75 mm, 100 mm) of the steel fiber layer was investigated. The evolution of the crack propagation behavior was analyzed using the digital image correlation (DIC) technique. The results showed that the steel fiber layer thickness of 75 mm has the best flexural behavior. Moreover, the crack propagation path is more tortuous. The maximum value of crack opening displacement (COM) increases with the increase in fiber thickness. In addition, increasing the bottom layer thickness can increase the height of the tensile zone, but the interface inhibits the increase of the tensile zone.

10.
Org Lett ; 23(3): 1118-1122, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33496598

RESUMO

A chiral phosphoric acid-catalyzed enantioselective condensation of 2,2-disubstituted cyclobutane-1,3-diones with a primary amine is described. This reaction offered a mild and efficient protocol for constructing quaternary carbon-containing cyclobutanes in good to high yields and enantioselectivities. This reaction is the first catalytic desymmetrizing carbonyl-amine condensation reaction and also represents the first catalytic desymmetrizing reaction of prochiral cyclobutane-1,3-dione.

11.
RSC Adv ; 9(58): 33716-33721, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-35528871

RESUMO

We report herein a new microporous neutral three-dimensional (3D) metal-organic framework [Cu2(L)(DMF)(H2O)]·guest (1·guest) composed of copper paddle-wheel and flexible tetracarboxylic acid linkers (DMF = N,N-dimethylformamide, H4L = tetrakis[(6-carboxynaphthoxy)methyl]methane). Surprisingly, this MOF with neutral cavities can not only extract pure quercetin (QT) but also convert it into Cu-QT during the desorption process. It has been well characterized by UV-vis, IR, ESI-MS and TEM-EDS studies. Moreover, it can efficiently extract natural product QT from fresh QT-rich onion juice and rapidly convert it into Cu-QT with a relatively high conversion rate.

12.
Dalton Trans ; 46(26): 8350-8353, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28627578

RESUMO

A two-dimensional porous framework SHU-1 could undergo solvent-induced structural transformations to SHU-1a in methanol and SHU-1b in water. SHU-1, SHU-1a and SHU-1b showed selective adsorption towards malachite green.

13.
Front Med ; 11(1): 32-47, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28220457

RESUMO

One of the primary purposes of the innovative development of ethnomedicines is to use their excellent safety and significant efficacy to serve a broader population. To achieve this purpose, modern scientific and technological means should be referenced, and relevant national laws and regulations as well as technical guides should be strictly followed to develop standards and to perform systemic research in producing ethnomedicines. Finally, ethnomedicines, which are applied to a limited extent in ethnic areas, can be transformed into safe, effective, and quality-controllable medical products to relieve the pain of more patients. The innovative development path of ethnomedicines includes the following three primary stages: resource study, standardized development research, and industrialization of the achievements and efforts for internationalization. The implementation of this path is always guaranteed by the research and development platform and the talent team. This article is based on the accumulation of long-term practice and is combined with the relevant disciplines, laws and regulations, and technical guidance from the research and development of ethnomedicines. The intention is to perform an in-depth analysis and explanation of the major research thinking, methods, contents, and technical paths involved in all stages of the innovative development path of ethnomedicines to provide useful references for the development of proper ethnomedicine use.


Assuntos
Desenvolvimento Industrial/tendências , Medicina Tradicional/normas , Medicina Tradicional/tendências , Pesquisa/normas , Animais , Descoberta de Drogas , Humanos , Internacionalidade , Invenções
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA