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1.
Nanotechnology ; 34(23)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36877995

RESUMO

In this work, ultrafast carrier dynamics of mechanically exfoliated 1T-TiSe2flakes from the high-quality single crystals with self-intercalated Ti atoms are investigated by femtosecond transient absorption spectroscopy. The observed coherent acoustic and optical phonon oscillations after ultrafast photoexcitation reveal the strong electron-phonon coupling in 1T-TiSe2. The ultrafast carrier dynamics probed in both visible and mid-infrared regions indicate that some photogenerated carriers localize near the intercalated Ti atoms and form small polarons rapidly within several picoseconds after photoexcitation due to the strong and short-range electron-phonon coupling. The formation of polarons leads to a reduction of carrier mobility and a long-time relaxation process of photoexcited carriers for several nanoseconds. The formation and dissociation rates of the photoinduced polarons are dependent on both the pump fluence and the thickness of TiSe2sample. This work offers new insights into the photogenerated carrier dynamics of 1T-TiSe2, and emphasizes the effects of intercalated atoms on the electron and lattice dynamics after photoexcitation.

2.
Nanotechnology ; 31(6): 065701, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31614341

RESUMO

In this study, we have reported nitrogen-doped graphite C coated Co nanocomposite (Co@CN) catalysts synthesized by one-step arc discharge method. The surface compositions, morphologies and the catalytic properties of the Co@CN nanocomposites were studied minutely. The results reveal that the prepared Co@CN nanocomposites have typical core-shell structure and show highly efficient catalytic performance in a reduction of 4-nitrophenol (4-NP), rhodamine and methylene blue. Their rate constant (Kapp) is 0.074 s-1 in a reduction of 4-NP, which is much higher than that of reported transition metal-based catalysts. Moreover, the overpotential of Co@CN is only 96 mV at a current density of 10 mA cm-2 in alkaline solution, showing high electrocatalytic activities in the hydrogen evolution reaction. The excellent synergistic effect between nitrogen-doped graphite C shell and magnetic Co core enables the Co@CN nanocomposites catalysts to hold abundant active sites and to transmit rapidly electron ability, resulting in Co@CN nanocomposite catalysts having a highly efficient catalytic nature.

3.
Heliyon ; 10(9): e30555, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726183

RESUMO

Background: Rheumatoid arthritis (RA) is a chronic inflammatory disease that leads to progressive joint damage. Circular RNA (circRNA) can regulate the inflammatory response of fibroblast-like synoviocytes (FLSs) in RA, influencing the disease progression. Paeoniflorin (PF) is the main active ingredient extracted from Paeonia lactiflora and is known for its anti-inflammatory effect. This study aims to explore the potential mechanisms by which hsa_circ_009012 and PF regulate the inflammatory response in RA. Methods: RNA expression of hsa_circ_009012, has-microRNA-1286 (miR-1286), toll-like receptor 4 (TLR4), NOD-like receptor thermal protein domain associated protein 3 (NLRP3) was assessed by real-time quantitative polymerase chain reaction (RT-qPCR) or western blotting (WB). Cell inflammation markers (TNF-α, IL-1ß, IL-6) were assessed by RT-qPCR and immunofluorescence (IF). Counting Kit-8 (CCK-8) assay, flow cytometry, and transwell assay were utilized to test cell viability, cell cycle distribution, and migration. Results: Hsa_circ_009012 was highly expressed in RA-FLS. Hsa_circ_009012 over-expression facilitated the inflammation in RA-FLS and was closely associated with the miR-1286/TLR4 axis. Paeoniflorin inhibited inflammation and the expression of hsa_circ_009012 and TLR4, while upregulating the expression of miR-1286 in RA-FLS. Moreover, the upregulation of hsa_circ_009012 reversed the repressive effect of paeoniflorin on RA-FLS progression. Conclusion: Paeoniflorin inhibits the inflammation of RA-FLS via mediating the hsa_circ_009012/miR-1286/TLR4/NLRP3 axis.

4.
Cell Signal ; 123: 111373, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39214267

RESUMO

BACKGROUND: Transforming growth factor-beta1 (TGF-ß1)-mediated renal fibrosis is a critical pathological process of chronic kidney disease worsening to end-stage renal disease. Recent studies have shown that long noncoding RNA H19 (lncRNA H19) is widely involved in the formation and progression of fibrosis in multiple organs. However, its molecular events in renal fibrosis remain to be elucidated. METHODS: Rats were treated with adenine intragastrically and HK-2 cells were induced by TGF-ß1 to construct renal fibrosis models in vivo and in vitro, respectively. Renal histopathological examination was performed using HE and Masson staining. Gene expression levels of interleukin-1beta (IL-1ß), tumor necrosis factor-alpha (TNF-α), TGF-ß1, fibronectin (Fn), alpha-smooth muscle actin (α-SMA), H19, let-7b-5p, TGF-ß receptor 1 (TGF-ßR1), and type I collagen (COL1A1) were detected by qRT-PCR. Immunohistochemistry, immunofluorescence, and western blot analysis were used to evaluate the expression of renal fibrosis biomarkers. Dual-luciferase reporter assay was used to verify the presence of binding sites between H19 and let-7b-5p, and between let-7b-5p and TGF-ßR1 and COL1A1. RESULTS: H19 was overexpressed in both in vivo and in vitro renal fibrosis models. H19 knockdown significantly reversed TGF-ß1-induced upregulation of fibronectin, COL1A1, and α-SMA and downregulation of E-cadherin in HK-2 cells, accompanied by an increase in let-7b-5p. Let-7b-5p was bound to H19 in HK-2 cells, and its overexpression inhibited TGF-ß1-induced HK-2 cell fibrosis. Further experiments determined that let-7b-5p directly targets TGF-ßR1 and COL1A1 in HK-2 cells. In addition, inhibition of let-7b-5p reversed the reduction in HK-2 cell fibrosis induced by H19 knockdown. Finally, knockdown of H19 alleviated renal fibrosis in vivo and was associated with regulation of the let-7b-5p/TGF-ßR1/COL1A1 axis. CONCLUSION: Our results indicate that knockdown of H19 inhibits renal tubular epithelial fibrosis by negatively regulating the let-7b-5p/TGF-ßR1/COL1A1 axis, which may provide new mechanistic insights into CRF progression.


Assuntos
Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo I , Fibrose , MicroRNAs , RNA Longo não Codificante , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo I , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Animais , MicroRNAs/metabolismo , MicroRNAs/genética , Humanos , Ratos , Cadeia alfa 1 do Colágeno Tipo I/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Masculino , Colágeno Tipo I/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Linhagem Celular , Rim/patologia , Rim/metabolismo , Transdução de Sinais
5.
Adv Mater ; 36(27): e2403154, 2024 Jul.
Artigo em Holandês | MEDLINE | ID: mdl-38631700

RESUMO

Van der Waals (vdW) ferromagnetic materials have emerged as a promising platform for the development of 2D spintronic devices. However, studies to date are restricted to vdW ferromagnetic materials with low Curie temperature (Tc) and small magnetic anisotropy. Here, a chemical vapor transport method is developed to synthesize a high-quality room-temperature ferromagnet, Fe3GaTe2 (c-Fe3GaTe2), which boasts a high Tc = 356 K and large perpendicular magnetic anisotropy. Due to the planar symmetry breaking, an unconventional room-temperature antisymmetric magnetoresistance (MR) is first observed in c-Fe3GaTe2 devices with step features, manifesting as three distinctive states of high, intermediate, and low resistance with the sweeping magnetic field. Moreover, the modulation of the antisymmetric MR is demonstrated by controlling the height of the surface steps. This work provides new routes to achieve magnetic random storage and logic devices by utilizing the room-temperature thickness-controlled antisymmetric MR and further design room-temperature 2D spintronic devices based on the vdW ferromagnet c-Fe3GaTe2.

6.
Front Immunol ; 14: 1301545, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38292492

RESUMO

Background: Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease that affects multiple joints and has adverse effects on various organs throughout the body, often leading to a poor prognosis. Recent studies have shown significant progress in the research of non-coding RNAs (ncRNAs) in RA. Therefore, this study aims to comprehensively assess the current status and research trends of ncRNAs in RA through a bibliometric analysis. Methods: This study retrieved articles relevant to ncRNAs and RA from the Science Citation Index Expanded Database of the Web of Science Core Collection between January 1st, 2003, and July 31st, 2023. The relevant articles were screened based on the inclusion criteria. VOSviewer and CiteSpace are utilized for bibliometric and visual analysis. Results: A total of 1697 publications were included in this study, and there was a noticeable increase in annual publications from January 1st, 2003, to July 31st, 2023. China, the United States, and the United Kingdom were the most productive countries in this field, contributing to 43.81%, 13.09%, and 3.87% of the publications. Anhui Medical University and Lu Qianjin were identified as the most influential institution and author. Frontiers In Immunology stood out as the most prolific journal, while Arthritis & Rheumatology was the most co-cited journal. Additionally, the research related to "circular RNA", "oxidative stress", "proliferation", and "migration" have emerged as new hotspots in the field. Conclusion: In this study, we have summarized the publication characteristics related to ncRNA and RA and identified the most productive countries, institutions, authors, journals, hot topics, and trends.


Assuntos
Artrite Reumatoide , Humanos , Artrite Reumatoide/genética , Bibliometria , China , Bases de Dados Factuais , RNA não Traduzido
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