Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Inorg Chem ; 62(38): 15711-15718, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37695723

RESUMO

Exploring highly efficient blue-emissive lead-free halide materials is a significant and challenging objective in the study of luminescent materials. This study reports the synthesis of a new zero-dimensional (0D) hybrid zinc halide of [CYP]ZnBr4 (CYP = 1-cyclohexylpiperazine) containing an isolated [ZnBr4]2- tetrahedron. [CYP]ZnBr4 exhibits strong blue light emission with a high photoluminescence quantum yield (PLQY) of 79.22%, surpassing all previously reported 0D zinc halide counterparts. According to the theoretical and experimental studies, the blue light emission is attributed to intrinsic self-trapped excitons resulting from strong electron-phonon coupling and structural deformation. Importantly, [CYP]ZnBr4 demonstrates excellent structural and luminescence stability toward high temperatures (180 °C) over at least half a month. High luminescence efficiency and stability enable [CYP]ZnBr4 to be an efficient blue phosphor to fabricate white light-emitting diodes (LEDs), which produces high-quality white light with a color rendering index (CRI) of 93.1 and a correlated color temperature (CCT) of 5304 K, closely resembling natural sunlight. This white LED also exhibits consistent performance and stability across different drive currents, suggesting the potential for high-power optoelectronic applications. Overall, this study paves the way for the utilization of 0D hybrid halides in advanced solid-state lighting applications.

2.
Angew Chem Int Ed Engl ; 61(35): e202206437, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35670095

RESUMO

A convenient and rapid detection method for methanol in ethanol remains a major challenge due to their indistinguishable physical properties. Herein, a novel fluorescence probe based on perovskite was successfully designed to overcome this bottleneck. We report a new zero-dimensional (0D) hybrid perovskite of [MP]2 Inx Sb1-x Cl7 ⋅ 6 H2 O (MP=2-methylpiperazine) displaying an unusual green light emission with near-unity photoluminescence quantum yield. Remarkably, this 0D perovskite exhibits reversible methanol-response luminescence switching between green and yellow color but fail in any other organic vapors. Even for blended alcohol solutions, the luminescent probe exhibits excellent sensing performance with multiple superiorities of rapid response time (30 s) and ultra-low detection limit (40 ppm), etc. Therefore, this 0D perovskite can be utilized as a perfect fluorescence probe to detect traces of methanol from ethanol with ultrahigh sensitivity, selectivity and repeatability. To the best of our knowledge, this work represents the first perovskite as fluorescence probe for methanol with wide potential in environmental monitoring and methanol detection, etc.

3.
J Integr Neurosci ; 19(4): 651-662, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33378839

RESUMO

Recent studies have shown that Nogo-A and the Nogo-A receptor affect ß-amyloid metabolism and the downstream Rho GTP enzyme signaling pathway, which may affect the levels of ß-amyloid and tau. Nogo-A may play a key role in the pathogenesis of Alzheimer's disease. However, the underlying molecular mechanisms of Fasudil treatment in Alzheimer's disease are not yet clear. Our results have found that Fasudil treatment for two months substantially ameliorated behavioral deficits, diminished ß-amyloid plaque and tau protein pathology, and alleviated neuronal apoptosis in APP/PS1 transgenic mice. More importantly, two well-established markers for synaptic function, growth-associated protein 43 and synaptophysin, were upregulated after Fasudil treatment. Finally, the levels of Nogo-A, Nogo-A receptor complex NgR/p75NTR/LINGO-1 and the downstream Rho/Rho kinase signaling pathway were significantly reduced. These findings suggest that Fasudil exerts its neuroprotective function in Alzheimer's disease by inhibiting the Nogo-A/NgR1/RhoA signaling pathway.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas tau/efeitos dos fármacos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Nogo/efeitos dos fármacos , Receptor Nogo 1/efeitos dos fármacos , Quinases Associadas a rho/efeitos dos fármacos
4.
Chem Commun (Camb) ; 60(20): 2784-2787, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38362615

RESUMO

Environmentally friendly and highly efficient blue luminescent materials are an unremitting pursuit in the optoelectronic field. Herein, we assembled a new 0D lead-free metal halide of (F-PPA)ZnBr4, which exhibits narrow blue light emission with a remarkable PLQY of 50.15%, high stability and high detection sensitivity toward UV light. These results indicate the potential for the application of low-dimensional zinc-based halides in multiple optoelectronic devices.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(3): 686-9, 2013 Mar.
Artigo em Zh | MEDLINE | ID: mdl-23705433

RESUMO

SH-SY5Y cell line treated with 6-hydroxydopamine (6-OHDA) is a classical Parkinson's disease (PD). In the present study, synchrotron-based Fourier transform infrared (FTIR) microspectroscopy was used to analyze the biochemical composition of SH-SY5Y cell line treated with 6-OHDA. The detailed spectral analyses show the significant changes in cellular compositions such as lipids, proteins and nucleic acids in SH-SY5Y cells treated with 6-OHDA compared to control SH-SY5Y cells. As a result, the unsaturation levels of phospholipids decrease in SH-SY5Y cells treated with 6-OHDA compared to control cells, the analysis of protein secondary structure shows the significantly higher ratio of beta-sheet in PD cells compared to that of control cells, and the content of nuclear acid is highly decreased compared to that of control cells, suggesting that 6-OHDA induces the serious oxidative damage in SH-SY5Y cells. These findings suggest that SR-FTIR is an effective and precise technical tool to probe the biochemical changes of cells and then evaluate the pathological damage in cells.


Assuntos
Neuroblastoma/patologia , Oxidopamina/toxicidade , Doença de Parkinson/patologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Linhagem Celular Tumoral , Humanos , Neuroblastoma/metabolismo , Estresse Oxidativo , Estrutura Secundária de Proteína
6.
RSC Adv ; 13(28): 19039-19045, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37362341

RESUMO

Organic-inorganic hybrid low-dimensional lead halides have garnered significant interest in the realm of solid-state optical materials due to their unique properties and potential applications. In this study, we report the synthesis, characterization and application of Mn2+-doped one-dimensional (1D) [AEP]PbCl5·H2O hybrid lead halide perovskites with tunable photoluminescence properties. The Mn2+ doping leads to a redshift of the dominant emission wavelength from 463 nm to 630 nm, with the optimal doping concentration resulting in an enhanced photoluminescence quantum yield (PLQY) from less than 1% to 8.96%. The structural and optical stability of these doped perovskites have been thoroughly investigated revealing excellent performance under humid and high-temperature conditions. Perovskite-PVP composite films exhibit high crystallization and bright orange-red emission under UV excitation. Furthermore, we demonstrate the successful fabrication of a white LED device using the Mn2+-doped perovskite in combination with commercial green and blue phosphors. The fabricated LED exhibits a high color rendering index (CRI) of 87.2 and stable electroluminescence performance under various operating currents and extended operation times. Our findings highlight the potential of Mn2+-doped 1D hybrid lead halide perovskites as efficient and stable phosphors for high-performance white light emitting diodes and other optoelectronic applications.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 113-7, 2012 Jan.
Artigo em Zh | MEDLINE | ID: mdl-22497140

RESUMO

Synchrotron radiation based-Fourier transform infrared microspectroscopy (SR-FTIR) was used to preliminarily investigate the biochemical composition of the hippocampal neurons for 6-hydroxydopamine-lesioned rats and normal rats. Spectral analysis showed that in PD samples, the CH2 asymmetric and symmetric vibrational absorption of integral area at 2 924 and 2 850 cm(-1) and the intensity of C=O vibrational absorption at 1 736 cm(-1) (assigned to the lipid functional group) increase compared to normal samples, which indicate that lipid content increased in PD sample; the PO2 asymmetric and symmetric vibrational absorption decrease compared to normal samples (assigned to the nucleic acid functional group; However no clear difference of the vibrational fingerprinting of protein between PD and normal samples was noticed. The present results suggest that the changes in biochemical composition in hippocampal neurons in PD rats probed by synchrotron radiation based-FTIR may contribute to the elucidation of PD pathology.


Assuntos
Hipocampo/patologia , Neurônios/efeitos dos fármacos , Oxidopamina , Doença de Parkinson/patologia , Animais , Modelos Animais de Doenças , Lipídeos , Proteínas , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Síncrotrons
8.
Opt Lett ; 36(4): 502-4, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21326436

RESUMO

A polarization-independent and high-diffraction-efficiency Fresnel lens is developed based on blue phase liquid crystals (BPLCs). The optically isotropic characteristic of BPLCs is used to produce a polarization-independent Fresnel lens. The small optical phase shift of BPLCs that is induced by the Kerr effect is sufficient for the BPLC Fresnel lens to have high theoretical and experimental diffraction efficiencies of 41% and ∼34%, respectively. An electrically erasable memory effect in the focusing diffraction at an electric field E>4.44 V/µm is observed. The electro-optical properties of the BPLC Fresnel lens are analyzed and discussed.

9.
J Tissue Viability ; 20(1): 35-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20089405

RESUMO

Introduce a reliable stowage by means of syringe to preserve split-thickness-skin grafts.


Assuntos
Transplante de Pele , Seringas , Preservação de Tecido/métodos , Humanos
10.
J Neuroimmunol ; 346: 577284, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32652366

RESUMO

Emerging evidence suggests an association of Alzheimer's Disease (AD) with microglial and astrocytic dysregulation. Recent studies have proposed that activated microglia can transform astrocytes to a neurotoxic A1 phenotype, which has been shown to be involved in the promotion of neuronal damage in several neurodegenerative diseases, including AD. In the present study, we observed an obvious microglial activation and A1-specific astrocyte response in the brain tissue of APP/PS1 Tg mice. Fasudil treatment improved the cognitive deficits of APP/PS1 Tg mice, inhibited microglial activation and promoted their transformation to an anti-inflammatory phenotype, and further shifted astrocytes from an A1 to an A2 phenotype. Our experiments suggest Fasudil exerted these functions by inhibing the expression of TLR4, MyD88, and NF-κB, which are key mediators of inflammation. Using in vitro experiments, we further validated in vivo findings. Our cell experiments indicated that Fasudil induces a shift of inflammatory microglia towards an anti-inflammatory phenotype. LPS-induced microglia-conditioned medium promotes A1 astrocytic polarization, but Fasudil treatment resulted in a direct transformation of A1 astrocytes to A2. To summarize, our results show that Fasudil inhibits the neurotoxic activation of microglia and shifts astrocytes towards a neuroprotective A2 phenotype, representing a promising candidate for AD treatment.

12.
Zhonghua Shao Shang Za Zhi ; 29(5): 432-5, 2013 Oct.
Artigo em Zh | MEDLINE | ID: mdl-24360001

RESUMO

OBJECTIVE: To explore the operative technique and clinical results of using peroneal perforator-based sural neurofasciocutaneous flaps to repair skin and soft tissue defects in lower extremities. METHODS: From January 2009 to March 2012, 26 patients with skin and soft tissue defects at distal region of leg and foot were hospitalized. Among them, 9 patients suffered from tendon or bone exposure at the distal region of leg after injury due to traffic accident; 4 patients suffered from skin defects in the ankle as a result of electric injury; 8 patients suffered from chronic ulcer at the distal part of leg and foot; 5 patients suffered from plantar pressure ulcer. After debridement, soft tissue defect sizes ranged from 11 cm×5 cm to 18 cm×13 cm. According to the position and size of the defects, peroneal perforator-based sural neurofasciocutaneous flaps were designed and procured to repair the skin and soft tissue defects. The size of flaps ranged from 12 cm×6 cm to 20 cm×15 cm. Flap donor sites were closed by direct suture or skin grafting. RESULTS: Twenty-five flaps survived completely. Only one flap suffered partial margin necrosis in the size of 2 cm×1 cm, which was healed after dressing change. Patients were followed up for 6 to 12 months. The appearance and sensation of flaps were satisfactory; no ulcer occurred; the movement of lower extremities was normal. CONCLUSIONS: It is suitable to repair the skin and soft tissue defects at distal region of leg and foot with the peroneal perforator-based sural neurofasciocutaneous flap, as it possesses reliable blood supply, long and non-bulky pedicle, and sufficient available size. The operation is also easy to perform.


Assuntos
Extremidade Inferior/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões dos Tecidos Moles/cirurgia , Nervo Sural/transplante , Retalhos Cirúrgicos/irrigação sanguínea , Retalhos Cirúrgicos/inervação , Adulto Jovem
14.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 24(3): 184-6, 2008 May.
Artigo em Zh | MEDLINE | ID: mdl-18717350

RESUMO

OBJECTIVE: To analyses the clinical application of thoracodorsal artery perforator flaps (TAP). METHODS: We used free or pedicled TAP flaps in 7 patients from Aug 2006 to April 2007, The age ranged from 7 to 42 years old, the perforator arteries was detected and labeled with a hand held Doppler flowmeter, the size of flaps ranged from 6 cm x 9 cm - 12 cm x 16 cm, the flaps designed with perforator artery included, all the flaps are based on the first perforator artery. RESULTS: All the flaps survived well, no complication occurred with lowest donor site morbidity. CONCLUSIONS: The thoracodorsal artery flap with latissimus dorsal muscle saved is a thin and reliable flaps with robust of blood supply, the flap can reduce significantly donor site morbidity and is a good choice for reconstructive surgery.


Assuntos
Retalhos Cirúrgicos/irrigação sanguínea , Artérias Torácicas/transplante , Adolescente , Adulto , Dorso/irrigação sanguínea , Criança , Feminino , Humanos , Masculino , Procedimentos de Cirurgia Plástica/métodos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA