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1.
Adv Sci (Weinh) ; : e2401131, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896817

RESUMO

9,9-bis (diphenylphosphorylphenyl) fluorene (FDPO) and dibenzotetrathienoacene (DBTTA), are synthesized as the neutral and anionic ligands, respectively, to prepare the ErIII coordination polymer [Er(DBTTA)3(FDPO)]n. Based on the intramolecular energy transfer, optical gains at 1.5 µm are demonstrated in [Er(DBTTA)3(FDPO)]n-doped polymer waveguides under excitations of low-power light-emitting diodes (LEDs) instead of laser pumping. A ligand-sensitization scheme between organic ligands and Er3+ ions under an excitation of an ultraviolet (UV) LED is established. Relative gains of 10.5 and 8.5 dB cm-1 are achieved at 1.53 and 1.55 µm, respectively, on a 1-cm-long SU-8 channel waveguide with a cross-section of 2 × 3 µm2 and a 1.5-µm-thick [Er(DBTTA)3(FDPO)]n-doped polymethylmethacrylate (PMMA) as upper cladding. The ErIII coordination polymer [Er(DBTTA)3(FDPO)]n can be conveniently integrated with various low-loss inorganic waveguides to compensate for optical losses in the C-band window. Moreover, by relying on the intramolecular energy transfer and UV LED top-pumping technology, it is easy to achieve coupling packaging of erbium-doped waveguide amplifiers (EDWAs) with pump sources in planar photonic integrated chips, effectively reducing the commercial costs.

2.
J Am Chem Soc ; 146(25): 17114-17121, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38870413

RESUMO

Near-infrared luminescent rare-earth organic complexes have attracted intensive attention in the field of optical waveguide amplification. However, their optical gains were commonly less than 4 dB/cm due to limited doping concentrations. Herein, two one-dimensional (1D) Nd3+ coordination chains, namely, [Nd(TTA)3(DBTDPO)]n (Nd1) and [Nd(TTA)3(DPEPO)]n (Nd2), bridged by phosphine oxide ligands were developed for the neodymium-doped waveguide amplifier. Despite its P-P distance being similar to DBTDPO, the different P═O orientation of DPEPO renders markedly shorter intra- and interchain Nd-Nd distances for Nd2 in comparison to Nd1. Furthermore, the weaker intermolecular interactions alleviate the quenching effect for Nd2. Therefore, Nd2 can provide more locally concentrated and radiative Nd3+ ions, leading to a larger Nd3+-characteristic 1.06 µm emission intensity and duration than Nd1. Based on embedded and evanescent-field waveguide structures, Nd2 achieves state-of-the-art gain maxima of 5.7 and 4.9 dB/cm as well as outstanding gain stability. These results indicate that controllable coordination assembly of lanthanide ions in multidimension provides a flexible approach to combine local high-density outputs and effective suppression of quenching.

3.
Adv Mater ; 35(12): e2209239, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36688343

RESUMO

Chelate phosphine oxide ligand (9,9-dimethyl-9H-xanthene-4,5-diyl) bis (diphenylphosphineoxide) (XPO) is prepared as a neutral ligand to synthesize complex Nd (TTA)3 (XPO) (TTA = 2-thenoyltrifluoroacetone). An appropriate energy gap between the XPO and TTA ligands, which can support two additional energy transfer routines from the first excited triplet state (T1 ) energy level of the XPO to that of the TTA, improves energy transfer in the Nd complex. Based on intramolecular energy transfer mechanism, optical gains at 1.06 and 1.31 µm are demonstrated in Nd (TTA)3 (XPO)-doped polymer waveguides with the excitation of low-power light-emitting diodes (LEDs) instead of semiconductor lasers as pump sources. Using the vertical top-pumping mode of a 365 nm LED, relative gains of 22.5 and 8.4 dB cm-1 are obtained at 1.06 and 1.31 µm, respectively, in a 0.2 cm long embedded waveguide with a cross-section of 8 × 5 µm2 . The active core layer is Nd (TTA)3 (XPO)-doped SU-8 polymer. Moreover, relative gains are achieved in evanescent-field waveguide with a cross-section of 6 × 4 µm2 . The 21.0 and 5.6 dB cm-1 relative gains are achieved at 1.06 and 1.31 µm, respectively, with a net gain of 13.8 ± 0.3 dB cm-1 obtained at 1.06 µm in a 0.9 cm long SU-8 waveguide with Nd (TTA)3 (XPO)-doped polymethylmethacrylate as upper cladding.

4.
Cell Mol Biol (Noisy-le-grand) ; 67(2): 44-49, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34817340

RESUMO

The aim of the current study was to investigate the anti-lung cancer effects of astragalin. Studies were also undertaken to evaluate its effects on apoptosis induction, ROS production, cellular migration and invasion and JAK/STAT3 signalling pathway. MTT assay was used to evaluate cell viability in NSCLC A549 cells after exposure to astragalin molecule. Apoptosis was investigated using AO/EB staining, comet assay and western blotting assay. Fluorescence microscopy was implemented to estimate ROS production. Cell migration and invasion were measured using transwell chambers assay. Effects of astragalin on JAK/STAT pathway were investigated using western blotting assay. Results showed astragalin molecule induced inhibition of proliferation in A549 cells in a dose-dependent fashion. Further, the antiproliferative effects were found to mediate via apoptosis as suggested by AO/EB staining and western blotting assay. Astragalin modulated the expressions of caspase-3, caspase-9, Bax, Bak, Cyt-c Bcl-2, XIAP and Bcl-xL. Astragalin induced DNA damage in A549 cells which too indicated apoptotic cell death. Astragalin molecule enhanced the production of ROS by A549 cells. It inhibited both cell migration and invasion of A549 cells in a concentration-dependent manner. Finally, astragalin drug was observed with remarkable potential of targeting JAK/STAT pathway in A549 NSCLC cells. These results indicated that astragalin drug could prove helpful in lung cancer treatment and research provided more in-vivo studies are performed.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Janus Quinases/metabolismo , Quempferóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células A549 , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Caspases/metabolismo , Células Cultivadas , Ensaio Cometa , Dano ao DNA , Flavonoides/química , Flavonoides/farmacologia , Humanos , Quempferóis/química , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Estrutura Molecular , Invasividade Neoplásica
5.
Front Neurol ; 12: 659678, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557140

RESUMO

Silybin, a peculiar flavonoid compound derived from the fruit and seeds of Silybum marianum, exhibits strong anti-inflammatory activities. In the present study, we found that silybin effectively alleviated experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), via inhibition of dendritic cell (DC) activation and Th17 cell differentiation. Silybin treatment greatly ameliorated the disease severity and significantly declined inflammation and demyelination of the central nervous system (CNS) of EAE mice. Consistent with the disease development, silybin-treated bone marrow-derived DCs (BM-DCs) exhibited reduced costimulatory molecules (e.g., CD80 and CD86) and MHC II expression. These results demonstrated the distinguished bioactivity of silybin for suppressing DC activation, inhibiting pathogenic Th17 inflammatory cell responses, and, eventually, alleviating EAE severity. Taken together, our results show that silybin has high potential for the development of a novel therapeutic agent for the treatment of autoimmune diseases such as MS.

6.
Transl Cancer Res ; 8(5): 1806-1816, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35116931

RESUMO

BACKGROUND: This study aimed to explore the correlation of integrin-α7 (ITGA7) with common cancer stem cell marker (CD44 and CD133) expressions, clinicopathological characteristics and survival profiles in non-small cell lung cancer (NSCLC) patients. METHODS: Two hundred and seventy NSCLC patients who underwent resection were reviewed in this study and the expressions of ITGA7, CD44 and CD133 were detected using immunohistochemistry (IHC) assay in tumor tissue specimens. The clinical data (including age, gender, pathological grade, tumor size, lymph node metastasis (LYN), and TNM stage), survival data [including disease-free survival (DFS) and overall survival (OS)] were collected. RESULTS: The numbers of NSCLC patients with ITGA7 high expression, CD44 high expression and CD133 high expression were 170 (63.0%), 241 (89.3%) and 37 (13.7%) respectively, and ITGA7 expression was positively associated with CD44 expression and CD133 expression. ITGA7 high expression was associated with higher pathological grade, larger tumor size, LYN and elevated TNM stage. However, there was no correlation of ITGA7 expression with age or gender. As for survival, patients with ITGA7 high expression presented reduced DFS and OS compared with those with ITGA7 low expression. In addition, multivariate Cox's proportional hazards regression model analyses exhibited that ITGA7 high expression, higher pathological grade and LYN were independent risk factors for DFS and OS in NSCLC patients. CONCLUSIONS: ITGA7 expression positively correlates with CD44 and CD133 expressions, and its high expression associates with advanced tumor features as well as poor survivals in NSCLC.

7.
Int J Clin Exp Med ; 8(1): 52-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25784974

RESUMO

Lung volume reduction surgery usually gives rise to high postoperative morbidity and impedes its further application. Recently, a plethora of bronchoscopic lung volume reduction techniques such as one-way endobronchial valves, biological sealants, thermal vapor ablation, airway bypass stents and lung volume reduction coils have been extensively used in emphysema treatment. The current data for bronchoscopic lung volume reduction although not conclusive enough do present multiple safer ways compared with conventional surgery with few serious complications, lower cost and shortened hospital care. The bronchoscopic lung volume reduction will undergo continuous development as constant randomized trials are performed to prove its full efficacy.

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