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1.
Nanotechnology ; 34(45)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37356433

RESUMO

Organic-inorganic hybrid perovskite nanocrystals have become a very widely used as semiconductor light-emitting materials. However, perovskite nanocrystals face stability challenges, which is a key factor hindering their application. In this paper, by introducing water into the synthesis of formamidinium lead bromide (FAPbBr3) perovskite, ultra-stable FAPbBr3@PbBr(OH) fluorescent material was prepared. The photoluminescence intensity of the material after the addition of water increased 2.9 times compared with that before the addition of water. The excellent green fluorescence emission was still maintained after four cycles of wash-dry treatment. Meanwhile, it also exhibits good ultraviolet and thermal stability. The above enhanced performance of FAPbBr3nanocrystals is attributed the protection of PbBr(OH). In addition, the prepared material can be used in anti-counterfeit patterns. The anti-counterfeit patterns have good color rendering and the luminous color has a high dependence on temperature. Both of these features make it very valuable for various fluorescent anti-counterfeiting labels.

2.
Environ Sci Technol ; 57(11): 4406-4414, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36854052

RESUMO

CO2 emissions are unevenly distributed both globally and regionally within nation-states. Given China's entrance into the new stage of economic development, an updated study on the largest CO2 emitter's domestic emission distribution is needed for effective and coordinated global CO2 mitigation planning. We discovered that domestic CO2 emissions in China are increasingly polarized for the 2007-2017 period. Specifically, the domestically exported CO2 emissions from the less developed and more polluting northwest region to the rest of China has drastically increased from 165 Mt in 2007 to 230 Mt in 2017. We attribute the polarizing trend to the simultaneous industrial upgrading of all regions and the persistent disparity in the development and emission decoupling of China's regions. We also noted that CO2 emissions exported from China to the rest of the world has decreased by 41% from 2007 to 2017, with other developing countries filling up the vacancy. As this trend is set to intensify, we intend to send an alarm message to policy makers to devise and initiate actions and avoid the continuation of pollution migration.


Assuntos
Dióxido de Carbono , Poluição Ambiental , Dióxido de Carbono/análise , China , Indústrias , Desenvolvimento Econômico
3.
J Fluoresc ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38008861

RESUMO

Due to their persistent luminescence, persistent luminescent (PersL) materials have attracted great interest. In the biomedical field, the use of persistent luminescent nanoparticles (PLNPs) eliminates the need for continuous in situ excitation, thereby avoiding interference from tissue autofluorescence and significantly improving the signal-to-noise ratio (SNR). Although persistent luminescence materials can emit light continuously, the luminescence intensity of small-sized nanoparticles in vivo decays quickly. Early persistent luminescent nanoparticles were mostly excited by ultraviolet (UV) or visible light and were administered for imaging purposes through ex vivo charging followed by injection into the body. Limited by the low in vivo penetration depth, UV light cannot secondary charge PLNPs that have decayed in vivo, and visible light does not penetrate deep enough to reach deep tissues, which greatly limits the imaging time of persistent luminescent materials. In order to address this issue, the development of PLNPs that can be activated by light sources with superior tissue penetration capabilities is essential. Near-infrared (NIR) light and X-rays are widely recognized as ideal excitation sources, making persistent luminescent materials stimulated by these two sources a prominent area of research in recent years. This review describes NIR and X-ray excitable persistent luminescence materials and their recent advances in bioimaging.

4.
J Environ Manage ; 343: 118121, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224684

RESUMO

Anthropogenic global warming strategies on carbon mitigation are driven by encouraging green innovation and using carbon taxes, yet an empirical model to validate this is non-existing. Moreover, the existing stochastic effects by regression on population, wealth, and technology (STIRPAT) model has been found to lack policy tools on taxes and institutions that cut carbon emissions. This study amends the STIRPAT model with environmental technology, environmental taxes, and strong institutional frameworks to create a new model STIRPART(stochastic impacts by regression on population, affluence, regulation, and technology) to understand the factors impacting carbon pollution using the emerging 7 economies. Using data from 2000 to 2020, the Driscoll-Kraay fixed effects are employed in this analysis to conduct evidential tests of the impacts of environmental policies, eco-friendly innovations, and strong institutions. The outcomes indicate that environmental technology, environmental taxation, and institution quality decrease E7's carbon emissions by 0.170%, 0.080%, and 0.016%, respectively. It is recommended that E7 policymakers should adopt the STIRPART postulate as the theoretical basis for policies favoring environmental sustainability. The key contribution is the amendment of the STIRPAT model and the enhancement of the market-based mechanisms, such as patents, strong institutions, and carbon taxes, to enable environmental policy to be carried out sustainably and cost-effectively.


Assuntos
Condições Sociais , Impostos , Carbono , Política Ambiental , Poluição Ambiental , Dióxido de Carbono , Desenvolvimento Econômico
5.
Langmuir ; 38(46): 14355-14363, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36350293

RESUMO

Photothermal therapy (PTT) has attracted great attention as an anticancer treatment strategy. With the rapid development of nanomedicine, multifunctional inorganic nanophotothermal agents provide a new way to improve the effect of PTT. Herein, bovine serum albumin (BSA)-modified Bi nanosheets (Bi NSs) with good biocompatibility were synthesized by a facile redox and ball milling method and applied as a photothermal agent for the enhancement of PTT. Owing to the strong near-infrared absorption, Bi NSs exhibit high photothermal conversion efficiency (η = 36.17%) under 808 nm laser irradiation and can serve as a nanotherapeutic agent for cancer therapy. In addition, in vitro cell safety analysis also suggests that the toxicity of BSA-modified Bi NSs is negligible. Upon 808 nm irradiation, the uptake ability of tumor cells to Bi NSs@BSA has been improved. Moreover, Bi NSs@BSA also can be used as a good contrast agent for CT imaging and then to observe the distribution of materials in the tumor site. Finally, Bi NSs@BSA-mediated PTT results show a high ablation rate of A549 tumor cells both in vitro and in vivo. All results reveal that Bi NSs@BSA is a promising nanotherapeutic platform for PTT.


Assuntos
Nanopartículas , Neoplasias , Humanos , Linhagem Celular Tumoral , Nanomedicina , Neoplasias/patologia , Fototerapia/métodos , Terapia Fototérmica , Soroalbumina Bovina , Tomografia Computadorizada por Raios X , Nanoestruturas , Bismuto/química
6.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(4): 463-468, 2021 Jul 30.
Artigo em Zh | MEDLINE | ID: mdl-34363380

RESUMO

Objective The acceptance test of the physical performance for the newly installed PFX Gamma knife was carried out to provide a reference for the quality assurance of the equipment. Method According to the manufacturer's acceptance manual and Chinese health industry standards, the dose rate of the PFX Gamma knife with maximum collimators in the calibration center point, the focal spot dose distribution with all three collimator sizes, the distance between the RFP and the PPS calibration center point, and the multi-target position accuracy were measured by means of the acceptance tools. Results The average absorbed dose rate, as measured in April 29, 2019, was 3.295 Gy/min in the calibration center point by the maximum collimators, which was better than acceptance standard of 2.5 Gy/min. The focal spot dosimetry data measured by the film were basically the same as the TMR-10 data stored in the LGP. The difference in FWHM was 0.18±0.13 mm, and the difference in penumbra was 0.15±0.25 mm, which was normal and as expected. The distance between the RFP and PPS calibration center point in the three-dimensional space was 0.24 mm, which was better than the recommended value of the factory standard and the national standard. The maximum position deviation of multiple targets was 0.16 mm, which was also better than the factory standard of 0.5 mm. Conclusion The various physical performance indicators of the PFX Gamma knife met the acceptance standards of manufacturers and industries.


Assuntos
Radiocirurgia , Calibragem , Humanos , Radiometria , Dosagem Radioterapêutica
7.
Opt Express ; 28(8): 10714-10724, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403596

RESUMO

Organic-inorganic hybrid perovskite nanocrystals have been widely studied for their excellent photoelectric properties. However, the irregular morphologies of organic-inorganic hybrid perovskite nanocrystals have limited application in the field of lighting and display. From this, the regular morphologies of nanospheres, nanorods, nanoplatelets and MAPbBr3 (MA = CH3NH3 +) nanocrystals have been synthesized by regulating the type and proportion of auxiliary ligands. The phase evolution, morphology and fluorescent properties were systematically studied by the various instruments of XRD, TEM, PL/UV-vis spectroscopy and fluorescence decay analysis. With the morphologies changing from nanospheres to nanoplatelets, the emission peaks of MAPbBr3 nanocrystals red-shifted, and the lifetimes have increased gradually. The underlying mechanisms were thoroughly investigated and elucidated. On this basis, the role of acid and amine in the synthesis of MAPbBr3 nanocrystals was systematically studied by regulating the ratio of oleic acid and N-octylamine. The fluorescence kinetics of MAPbBr3 nanocrystals were studied by femtosecond transient absorption spectroscopy, and the charge carrier relaxation mechanism was clarified. Furthermore, the effect of temperature on the fluorescence properties of the nanocrystal was investigated in detail. Organic-inorganic hybrid perovskite nanocrystals with morphologies-controlled and excellent fluorescence properties are expected to be widely used in lighting and display fields.

8.
Luminescence ; 35(1): 34-42, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31423706

RESUMO

In this paper, two types of carbon quantum dot (CQDs) were prepared using biocompatible l-methionine as the carbon source and urea as the nitrogen source and a one-step hydrothermal treatment. By changing the reaction solvents (deionized (DI) water and dimethylformamide (DMF)), the maximum emission of the resulting CQDs shifted from blue to red light. Specifically, the emission wavelength of the CQDs moved from 433 nm to 625 nm following embedding of a new functional group (-CONH-) on the surface of the CQDs. Photoluminescence quantum yields of the CQDs with blue and red emission reached 64% and 61%, respectively. The R-CQDs were used to detect metal ions and a linear relationship was demonstrated between ln(F/F0 ) and Fe3+ concentration in the range 0-0.5 mmol/L with a detection limit of 0.067 µM. Therefore these R-CQDs have great potential as fluorescent probes for Fe3+ detection. We expect that the excellent water-soluble, biocompatible and optical properties of the CQDs developed in this work mean that they will be widely used to detect biological cells.


Assuntos
Carbono/química , Cor , Compostos Férricos/análise , Fluorescência , Corantes Fluorescentes/química , Pontos Quânticos/química , Corantes Fluorescentes/síntese química , Solventes/química , Espectrometria de Fluorescência
9.
Molecules ; 25(5)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32151026

RESUMO

The solar selective absorber coating (SSAC) are at the core of the efficient solar-thermal system. In this paper, for the first time, the Chromium-iron oxidation mixture cermet was successfully prepared on the surface of ultra-pure ferritic stainless steel by chemical coloring as SSAC. The coating surface has an optical trap structure, and the chromium-iron oxidation mixture cermet is used as an absorption layer to realize solar-thermal conversion. The solar absorptance (AM1.5) of the coating reached 93.66, and the thermal emittance was less than 13. After thermal shock tests at 25/300 °C done 32 times (accumulated 812.8 h), the Performance Criterion (PC) of the coating was 0.01375 < 0.05, showing outstanding thermal stability.


Assuntos
Cimentos Cermet/química , Cromo/química , Ferro/química , Oxirredução , Luz Solar , Fenômenos Químicos , Modelos Teóricos , Propriedades de Superfície , Termodinâmica
10.
J Appl Clin Med Phys ; 20(10): 24-32, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31460704

RESUMO

The purpose of this study was to investigate the potential advantages of the fixed-jaw technique (FJT) over the conventional split-field technique (SFT) for cervical and upper thoracic esophageal cancer (EC) patients treated with intensity-modulated radiotherapy. The SFT and FJT plans were generated for 15 patients with cervical and upper thoracic EC. Dosimetric parameters and delivery efficiency were compared. An area ratio (AR) of the jaw opening to multileaf collimator (MLC) aperture weighted by the number of monitor units (MUs) was defined to evaluate the impact of the transmission through the MLC on the dose gradient outside the PTV50.4, and the correlation between the gradient index (GI) and AR was analyzed. The FJT plans achieved a better GI and AR (P < 0.001). There was a positive correlation between the GI and AR in the FJT (r = 0.883, P < 0.001) and SFT plans (r = 0.836, P < 0.001), respectively. Moreover, the mean dose (Dmean ), V5Gy -V40Gy for the lungs and the Dmean , V5Gy -V50Gy for the body-PTV50.4 in the FJT plans were lower than those in the SFT plans (P < 0.05). The FJT plans demonstrated a reduction trend in the doses to the spinal cord PRV and heart, but only the difference in the heart Dmean reached statistical significance (P < 0.05). The FJT plans reduced the number of MUs and subfields by 5.5% and 17.9% and slightly shortened the delivery time by 0.23 min (P < 0.05). The gamma-index passing rates were above 95% for both plans. The FJT combined with target splitting can provide superior organs at risk sparing and similar target coverage without compromising delivery efficiency and should be a preferred intensity-modulated radiotherapy planning method for cervical and upper thoracic EC patients.


Assuntos
Neoplasias Esofágicas/radioterapia , Arcada Osseodentária/fisiologia , Órgãos em Risco/efeitos da radiação , Melhoria de Qualidade , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/normas , Neoplasias Torácicas/radioterapia , Idoso , Algoritmos , Humanos , Arcada Osseodentária/efeitos da radiação , Registro da Relação Maxilomandibular , Pessoa de Meia-Idade , Prognóstico , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos
11.
Molecules ; 24(4)2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30791537

RESUMO

(Gd0.93-xTb0.07Eux)2O3 (x = 0⁻0.10) phosphors shows great potential for applications in the lighting and display areas. (Gd0.93-xTb0.07Eux)2O3 phosphors with controlled morphology were prepared by a hydrothermal method, followed by calcination at 1100 °C. XRD, FE-SEM, PL/PLE, luminescent decay analysis and thermal stability have been performed to investigate the Eu3+ content and the effects of hydrothermal conditions on the phase variation, microstructure, luminescent properties and energy transfer. Optimum excitation wavelength at ~308 nm nanometer ascribed to the 4f8-4f75d¹ transition of Tb3+, the (Gd0.93-xTb0.07Eux)2O3 phosphors display both Tb3+and Eu3+ emission with the strongest emission band at ~611 nm. For increasing Eu3+ content, the Eu3+ emission intensity increased as well while the Tb3+ emission intensity decreased owing to Tb3+→Eu3+ energy transfer. The energy transfer efficiencies were calculated and the energy transfer mechanism was discussed in detail. The lifetime for both the Eu3+ and Tb3+ emission decreases with the Eu3+ addition, the former is due to the formation of resonant energy transfer net, and the latter is because of contribution by Tb3+→Eu3+ energy transfer. The phosphor morphology can be controlled by adjusting the hydrothermal condition (reaction pH), and the morphological influence to the luminescent properties (PL/PLE, decay lifetime, etc.) has been studied in detail.


Assuntos
Európio/química , Metais Terras Raras/química , Óxidos/química , Fósforo/química , Térbio/química
12.
Small ; 11(19): 2269-74, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25641809

RESUMO

Multilayered graphene and single-layered graphene are assembled onto perovskite films in the form of Schottky junctions and ohmic contacts, respectively, for the production of a graphene-based hole transporting material-free perovskite solar cell. Multilayered graphene extracts charge selectively and efficiently, delivering a higher efficiency of 11.5% than single-layered graphene (6.7%).

13.
Angew Chem Int Ed Engl ; 53(29): 7584-8, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24910179

RESUMO

Cost-effective electrocatalysts for the oxygen evolution reaction (OER) are critical to energy conversion and storage processes. A novel strategy is used to synthesize a non-noble-metal-based electrocatalyst of the OER by finely combining layered FeNi double hydroxide that is catalytically active and electric conducting graphene sheets, taking advantage of the electrostatic attraction between the two positively charged nanosheets. The synergy between the catalytic activity of the double hydroxide and the enhanced electron transport arising from the graphene resulted in superior electrocatalytic properties of the FeNi-GO hybrids for the OER with overpotentials as low as 0.21 V, which was further reduced to 0.195 V after the reduction treatment. Moreover, the turnover frequency at the overpotential of 0.3 V has reached 1 s(-1), which is much higher than those previously reported for non-noble-metal-based electrocatalysts.

14.
Pak J Pharm Sci ; 27(4 Suppl): 1049-55, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25016265

RESUMO

Using pesticides has double effects. On one hand, it contributes to pests control and regulates the growth of crops; On the other hand, it does harm to the environment. To develop ecological agriculture should not only emphasize the output level of agriculture to pursuit of economic efficiency, but also need to keep the ecological environment protected and focus on the social benefits during the development of the industry. As a large agricultural country in the world, China is vigorously promoting the development of ecological agriculture, which is bound to put forward to developing the pesticide industry and green ecological development requirements to promote the transformation and upgrading of agricultural pharmaceutical industry. This paper discusses the mechanism of pesticide pollution on the ecological environment and analyzes China's agricultural problems in the pharmaceutical industry. Then study on the development of Chinese green pesticides and try to find the proper paths of agricultural pharmaceutical to achieve industrial upgrading.


Assuntos
Agricultura , Indústria Farmacêutica , Praguicidas , China , Conservação dos Recursos Naturais , Ecossistema , Humanos , Propriedade Intelectual
15.
Neural Netw ; 176: 106380, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38754289

RESUMO

Most trackers formulate visual tracking as common classification and regression (i.e., bounding box regression) tasks. Correlation features that are computed through depth-wise convolution or channel-wise multiplication operations are input into both the classification and regression branches for inference. However, this matching computation with the linear correlation method tends to lose semantic features and obtain only a local optimum. Moreover, these trackers use an unreliable ranking based on the classification score and the intersection over union (IoU) loss for the regression training, thus degrading the tracking performance. In this paper, we introduce a deformable transformer model, which effectively computes the correlation features of the training and search sets. A new loss called the quality-aware focal loss (QAFL) is used to train the classification network; it efficiently alleviates the inconsistency between the classification and localization quality predictions. We use a new regression loss called α-GIoU to train the regression network, and it effectively improves localization accuracy. To further improve the tracker's robustness, the candidate object location is predicted by using a combination of online learning scores with a transformer-assisted framework and classification scores. An extensive experiment on six testing datasets demonstrates the effectiveness of our method. In particular, the proposed method attains a success score of 71.7% on the OTB-2015 dataset and an AUC score of 67.3% on the NFS30 dataset, respectively.


Assuntos
Redes Neurais de Computação , Humanos , Algoritmos , Tecnologia de Rastreamento Ocular
16.
Neural Netw ; 178: 106464, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38968779

RESUMO

For convenient transmission, omnidirectional images (ODIs) usually follow the equirectangular projection (ERP) format and are low-resolution. To provide better immersive experience, omnidirectional image super resolution (ODISR) is essential. However, ERP ODIs suffer from serious geometric distortion and pixel stretching across latitudes, generating massive redundant information at high latitudes. This characteristic poses a huge challenge for the traditional SR methods, which can only obtain the suboptimal ODISR performance. To address this issue, we propose a novel position attention network (PAN) for ODISR in this paper. Specifically, a two-branch structure is introduced, in which the basic enhancement branch (BE) serves to achieve coarse deep feature enhancement for extracted shallow features. Meanwhile, the position attention enhancement branch (PAE) builds a positional attention mechanism to dynamically adjust the contribution of features at different latitudes in the ERP representation according to their positions and stretching degrees, which achieves the enhancement for the differentiated information, suppresses the redundant information, and modulate the deep features with spatial distortion. Subsequently, the features of two branches are fused effectively to achieve the further refinement and adapt the distortion characteristic of ODIs. After that, we exploit a long-term memory module (LM), promoting information interactions and fusions between the branches to enhance the perception of the distortion, aggregating the prior hierarchical features to keep the long-term memory and boosting the ODISR performance. Extensive results demonstrate the state-of-the-art performance and the high efficiency of our PAN in ODISR.

17.
Neural Netw ; 172: 106153, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38306784

RESUMO

Human motion prediction is the key technology for many real-life applications, e.g., self-driving and human-robot interaction. The recent approaches adopt the unrestricted full-connection graph representation to capture the relationships inside the human skeleton. However, there are two issues to be solved: (i) these unrestricted full-connection graph representation methods neglect the inherent dependencies across the joints of the human body; (ii) these methods represent human motions using the features extracted from a single level and thus can neither fully exploit the various connection relationships among the human body nor guarantee the human motion prediction results to be reasonable. To tackle the above issues, we propose an adaptive multi-level hypergraph convolution network (AMHGCN), which uses the adaptive multi-level hypergraph representation to capture various dependencies among the human body. Our method has four different levels of hypergraph representations, including (i) the joint-level hypergraph representation to capture inherent kinetic dependencies in the human body, (ii) the part-level hypergraph representation to exploit the kinetic characteristics at a higher level (in comparison to the joint-level) by viewing some part of the human body as an entirety, (iii) the component-level hypergraph representation to model the semantic information, and (iv) the global-level hypergraph representation to extract long-distance dependencies in the human body. In addition, to take full advantage of the knowledge carried in the training data, we propose a reverse loss (i.e., adopting the future human poses to predict the historical poses reversely) to realize data augmentation. Extensive experiments show that our proposed AMHGCN can achieve state-of-the-art performance on three benchmarks, i.e., Human3.6M, CMU-Mocap, and 3DPW.


Assuntos
Benchmarking , Conhecimento , Humanos , Movimento (Física) , Semântica
18.
J Inflamm Res ; 17: 3527-3549, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836243

RESUMO

Ulcerative colitis (UC) is a chronic non-sp ecific inflammatory disease of the colorectal mucosa. Researchers have associated UC onset with familial genetics, lifestyle behavior, inflammatory immune factors, intestinal microbiota, and the integrity of the intestinal mucosal barrier. The primary therapeutic interventions for UC consist of pharmacological management to control inflammation and promote mucosal healing and surgical interventions. The available drugs effectively control and decelerate the progression of UC in most patients; nonetheless, their long-term administration can exert adverse effects and influence the therapeutic effect. Plant essential oils (EOs) refer to a group of hydrophobic aromatic volatile substances. EOs have garnered considerable attention in both domestic and international research because of their anti-inflammatory, antibacterial, and antioxidant properties. They include peppermint, peppercorns, rosemary, and lavender, among others. Researchers have investigated the role of EOs in medicine and have elucidated their potential to mitigate the detrimental effects of UC through their anti-inflammatory, antioxidant, antidepressant, and anti-insomnia properties as well as their ability to regulate the intestinal flora. Furthermore, EOs exert minimal toxic adverse effects, further enhancing their appeal for therapeutic applications. However, these speculations are based on theoretical experiments, thereby warranting more clinical studies to confirm their effectiveness and safety. In this article, we aim to provide an overview of the advancements in utilizing natural medicine EOs for UC prevention and treatment. We will explore the potential pathogenesis of UC and examine the role of EOs therapy in basic research, quality stability, and management specification of inadequate EOs for UC treatment. We intend to offer novel insights into the use of EOs in UC prevention and management.

19.
J Ethnopharmacol ; 328: 118007, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38492791

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Rosa damascena is an ancient plant with significance in both medicine and perfumery that have a variety of therapeutic properties, including antidepressant, anti-anxiety, and anti-stress effects. Rose damascena essential oil (REO) has been used to treat depression, anxiety and other neurological related disorders in Iranian traditional medicine. However, its precise mechanism of action remains elusive. AIM OF THE STUDY: The aim of this study was to investigate the impact and mechanism underlying the influence of REO on chronic unpredictable mild stress (CUMS) rats. MATERIALS AND METHODS: Gas chromatography-mass spectrometry (GC-MS) technique coupling was used to analyze of the components of REO. A CUMS rat model was replicated to assess the antidepressant effects of varying doses of REO. This assessment encompassed behavioral evaluations, biochemical index measurements, and hematoxylin-eosin staining. For a comprehensive analysis of hippocampal tissues, we employed transcriptomics and incorporated weighting coefficients by means of network pharmacology. These measures allowed us to explore differentially expressed genes and biofunctional pathways affected by REO in the context of depression treatment. Furthermore, GC-MS metabolomics was employed to assess metabolic profiles, while a joint analysis in Metscape facilitated the construction of a network elucidating the links between differentially expressed genes and metabolites, thereby elucidating potential relationships and clarifying key pathways regulated by REO. Finally, the expression of relevant proteins in the key pathways was determined through immunohistochemistry and Western blot analysis. Molecular docking was utilized to investigate the interactions between active components and key targets, thereby validating the experimental results. RESULTS: REO alleviated depressive-like behavior, significantly elevated levels of the neurotransmitter 5-hydroxytryptamine (5-HT), and reduced hippocampal neuronal damage in CUMS rats. This therapeutic effect may be associated with the modulation of the serotonergic synapse signaling pathway. Furthermore, REO rectified metabolic disturbances, primarily through the regulation of amino acid metabolic pathways. Joint analysis revealed five differentially expressed genes (EEF1A1, LOC729197, ATP8A2, NDST4, and GAD2), suggesting their potential in alleviating depressive symptoms by modulating the serotonergic synapse signaling pathway and tryptophan metabolism. REO also modulated the 5-HT2A-mediated extracellular regulated protein kinases-cAMP-response element binding protein-brain-derived neurotrophic factor (ERK-CREB-BDNF) pathway. In addition, molecular docking results indicated that citronellol, geraniol and (E,E)-farnesol in REO may serve as key active ingredients responsible for its antidepressant effects. CONCLUSIONS: This study is the first to report that REO can effectively alleviate CUMS-induced depression-like effects in rats. Additionally, the study offers a comprehensive understanding of its intricate antidepressant mechanism from a multi-omics and multi-level perspective. Our findings hold promise for the clinical application and further development of this essential oil.


Assuntos
Rosa , Ratos , Animais , Serotonina/metabolismo , Irã (Geográfico) , Simulação de Acoplamento Molecular , Ratos Sprague-Dawley , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Depressão/metabolismo , Transdução de Sinais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Sinapses/metabolismo , Estresse Psicológico/tratamento farmacológico , Hipocampo , Modelos Animais de Doenças
20.
Sci Technol Adv Mater ; 14(1): 015006, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27877564

RESUMO

Well-crystallized (Y0.97-x Tb0.03Eu x )2(OH)5NO3·nH2O (x = 0-0.03) layered rare-earth hydroxide (LRH) nanoflakes of a pure high-hydration phase have been produced by autoclaving from the nitrate/NH4OH reaction system under the optimized conditions of 100 °C and pH ∼7.0. The flakes were then converted into (Y0.97-x Tb0.03Eu x )2O3 phosphor nanoplates with color-tunable photoluminescence. Detailed structural characterizations confirmed that LRH solid solutions contained NO3- anions intercalated between the layers. Characteristic Tb3+ and Eu3+ emissions were detected in the ternary LRHs by selectively exciting the two types of activators, and the energy transfer from Tb3+ to Eu3+ was observed. Annealing the LRHs at 1100 °C produced cubic-lattice (Y0.97-x Tb0.03Eu x )2O3 solid-solution nanoplates with exposed 222 facets. Multicolor, intensity-adjustable luminescence was attained by varying the excitation wavelength from ∼249 nm (the charge transfer excitation band of Eu3+) to 278 nm (the 4f8-4f75d1 transition of Tb3+). Unitizing the efficient Tb3+ to Eu3+ energy transfer, the emission color of (Y0.97-x Tb0.03Eu x )2O3 was tuned from approximately green to yellowish-orange by varying the Eu3+/Tb3+ ratio. At the optimal Eu3+ content of x = 0.01, the efficiency of energy transfer was ∼91% and the transfer mechanism was suggested to be electric multipole interactions. The phosphor nanoplates developed in this work may be incorporated in luminescent films and find various lighting and display applications.

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