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1.
J Mol Neurosci ; 74(3): 79, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162890

RESUMO

Diabetic neuropathic pain (DNP) is a diabetic complication that causes severe pain and deeply impacts the quality of the sufferer's daily life. Currently, contemporary clinical treatments for DNP generally exhibit a deficiency in effectiveness. Electroacupuncture (EA) is recognized as a highly effective and safe treatment for DNP with few side effects. Regrettably, the processes via which EA alleviates DNP are still poorly characterized. Transient receptor potential vanilloid 1 (TRPV1) and phosphorylated calcium/calmodulin-dependent protein kinase II (p-CaMKII) are overexpressed on spinal cord dorsal horn (SCDH) in DNP rats, and co-localization is observed between them. Capsazepine, a TRPV1 antagonist, effectively reduced nociceptive hypersensitivity and downregulated the overexpression of phosphorylated CaMKIIα in rats with DNP. Conversely, the CaMKII inhibitor KN-93 did not have any impact on TRPV1. EA alleviated heightened sensitivity to pain caused by nociceptive stimuli and downregulated the level of TRPV1, p-CaMKIIα, and phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB) in DNP rats. Intrathecal injection of capsaicin, on the other hand, reversed the above effects of EA. These findings indicated that the CaMKII/CREB pathway on SCDH is located downstream of TRPV1 and is affected by TRPV1. EA alleviates DNP through the TRPV1-mediated CaMKII/CREB pathway.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Neuropatias Diabéticas , Eletroacupuntura , Ratos Sprague-Dawley , Canais de Cátion TRPV , Animais , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Eletroacupuntura/métodos , Ratos , Masculino , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Neuropatias Diabéticas/terapia , Neuropatias Diabéticas/metabolismo , Capsaicina/farmacologia , Capsaicina/análogos & derivados , Transdução de Sinais , Corno Dorsal da Medula Espinal/metabolismo , Benzenossulfonamidas , Benzilaminas
2.
Neuroreport ; 35(11): 692-701, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38874969

RESUMO

OBJECTIVE: Diabetic neuropathic pain (DNP) is one of the most prevalent symptoms of diabetes. The alteration of proteins in the spinal cord dorsal horn (SCDH) plays a significant role in the genesis and the development of DNP. Our previous study has shown electroacupuncture could effectively relieve DNP. However, the potential mechanism inducing DNP's genesis and development remains unclear and needs further research. METHODS: This study established DNP model rats by intraperitoneally injecting a single high-dose streptozotocin; 2 Hz electroacupuncture was used to stimulate Zusanli (ST36) and Kunlun (BL60) of DNP rats daily from day 15 to day 21 after streptozotocin injection. Behavioral assay, quantitative PCR, immunofluorescence staining, and western blotting were used to study the analgesic mechanism of electroacupuncture. RESULTS: The bradykinin B1 receptor (B1R) mRNA, nuclear factor-κB p65 (p65), substance P, and calcitonin gene-related peptide (CGRP) protein expression were significantly enhanced in SCDH of DNP rats. The paw withdrawal threshold was increased while body weight and fasting blood glucose did not change in DNP rats after the electroacupuncture treatment. The expression of B1R, p65, substance P, and CGRP in SCDH of DNP rats was also inhibited after the electroacupuncture treatment. CONCLUSION: This work suggests that the potential mechanisms inducing the allodynia of DNP rats were possibly related to the increased expression of B1R, p65, substance P, and CGRP in SCDH. Downregulating B1R, p65, substance P, and CGRP expression levels in SCDH may achieve the analgesic effect of 2 Hz electroacupuncture treatment.


Assuntos
Diabetes Mellitus Experimental , Regulação para Baixo , Eletroacupuntura , Hiperalgesia , Ratos Sprague-Dawley , Receptor B1 da Bradicinina , Corno Dorsal da Medula Espinal , Animais , Eletroacupuntura/métodos , Masculino , Corno Dorsal da Medula Espinal/metabolismo , Hiperalgesia/terapia , Hiperalgesia/metabolismo , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/complicações , Receptor B1 da Bradicinina/metabolismo , Receptor B1 da Bradicinina/genética , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/terapia , Ratos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/genética , Substância P/metabolismo
3.
Nat Commun ; 15(1): 4006, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740849

RESUMO

The preparation of atom-thick porous lattice hosting Å-scale pores is attractive to achieve a large ion-ion selectivity in combination with a large ion flux. Graphene film is an ideal selective layer for this if high-precision pores can be incorporated, however, it is challenging to avoid larger non-selective pores at the tail-end of the pore size distribution which reduces ion-ion selectivity. Herein, we develop a strategy to overcome this challenge using an electrochemical repair strategy that successfully masks larger pores in large-area graphene. 10-nm-thick electropolymerized conjugated microporous polymer (CMP) layer is successfully deposited on graphene, thanks to a strong π-π interaction in these two materials. While the CMP layer itself is not selective, it effectively masks graphene pores, leading to a large Li+/Mg2+ selectivity from zero-dimensional pores reaching 300 with a high Li+ ion permeation rate surpassing the performance of reported materials for ion-ion separation. Overall, this scalable repair strategy enables the fabrication of monolayer graphene membranes with customizable pore sizes, limiting the contribution of nonselective pores, and offering graphene membranes a versatile platform for a broad spectrum of challenging separations.

4.
ACS Nano ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38320296

RESUMO

Zero-dimensional pores spanning only a few angstroms in size in two-dimensional materials such as graphene are some of the most promising systems for designing ion-ion selective membranes. However, the key challenge in the field is that so far a crack-free macroscopic graphene membrane for ion-ion separation has not been realized. Further, methods to tune the pores in the Å-regime to achieve a large ion-ion selectivity from the graphene pore have not been realized. Herein, we report an Å-scale pore size tuning tool for single layer graphene, which incorporates a high density of ion-ion selective pores between 3.5 and 8.5 Å while minimizing the nonselective pores above 10 Å. These pores impose a strong confinement for ions, which results in extremely high selectivity from centimeter-scale porous graphene between monovalent and bivalent ions and near complete blockage of ions with the hydration diameter, DH, greater than 9.0 Å. The ion diffusion study reveals the presence of an energy barrier corresponding to partial dehydration of ions with the barrier increasing with DH. We observe a reversal of K+/Li+ selectivity at elevated temperature and attribute this to the relative size of the dehydrated ions. These results underscore the promise of porous two-dimensional materials for solute-solute separation when Å-scale pores can be incorporated in a precise manner.

5.
ACS Nano ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38324377

RESUMO

Porous graphene films are attractive as a gas separation membrane given that the selective layer can be just one atom thick, allowing high-flux separation. A favorable aspect of porous graphene is that the pore size, essentially gaps created by lattice defects, can be tuned. While this has been demonstrated for postsynthetic, top-down pore etching in graphene, it does not exist in the more scalable, bottom-up synthesis of porous graphene. Inspired by the mechanism of precipitation-based synthesis of porous graphene over catalytic nickel foil, we herein conceive an extremely simple way to tune the pore size. This is implemented by increasing the cooling rate by over 100-fold from -1 °C min-1 to over -5 °C s-1. Rapid cooling restricts carbon diffusion, resulting in a higher availability of dissolved carbon for precipitation, as evidenced by quantitative carbon-diffusion simulation, measurement of carbon concentration as a function of nickel depth, and imaging of the graphene nanostructure. The resulting enhanced grain (inter)growth reduces the effective pore size which leads to an increase of the H2/CH4 separation factor from 6.2 up to 53.3.

6.
J Pain Res ; 16: 4165-4180, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38078016

RESUMO

Purpose: This bibliometric research aims to delineate global publication trends and emerging research interests in the use of acupuncture for breast cancer (BC)-related symptoms treatment over the past three decades. Furthermore, it identifies influential institutions, potential collaborative partners, and future research trends, thereby providing guidance for relevant, novel research directions. Methods: Scientific publications related to acupuncture for BC-related symptoms were gathered from the Web of Science Core Collection (WoSCC) from 1993 to 2023. Four software applications were principally used to analyze the resulting data: the "bibliometrix" package in the R environment (version 4.2.3), VOSviewer, CiteSpace6.1.R6, and the bibliometrics website. These applications were employed to evaluate different parameters. Results: A total of 621 papers on acupuncture in BC-related symptoms treatment were analyzed. The United States, China, and South Korea contributed the most, with Memorial Sloan Kettering Cancer Center, and Columbia University leading institutions. It is interesting to mention that Mao, Jun J. and Molassiotis, A. feature among the top 10 authors and co-cited authors. JAMA is the leading journal, with an ongoing focus on acupuncture's effectiveness. Keywords show that the initial research focus was mainly on "vasomotor symptoms", but in recent years there has been a gradual shift towards "pain", "chemotherapy-induced peripheral neuropathy (CIPN)", "electroacupuncture", and "non-specific effects". Conclusion: Acupuncture has demonstrated a unique value in the process of adjuvant treatment of BC-related symptoms, and has been shown to be effective in reducing pain, eliminating fatigue, and improving quality of life. The study of the mechanisms of acupuncture and the application of electroacupuncture are possible future research priorities in this field. This study offers a deep perspective on acupuncture for BC research, highlighting key points and future trends.

7.
Nat Mater ; 22(11): 1387-1393, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37735526

RESUMO

Zeolitic imidazolate frameworks (ZIFs) are a subset of metal-organic frameworks with more than 200 characterized crystalline and amorphous networks made of divalent transition metal centres (for example, Zn2+ and Co2+) linked by imidazolate linkers. ZIF thin films have been intensively pursued, motivated by the desire to prepare membranes for selective gas and liquid separations. To achieve membranes with high throughput, as in ångström-scale biological channels with nanometre-scale path lengths, ZIF films with the minimum possible thickness-down to just one unit cell-are highly desired. However, the state-of-the-art methods yield membranes where ZIF films have thickness exceeding 50 nm. Here we report a crystallization method from ultradilute precursor mixtures, which exploits registry with the underlying crystalline substrate, yielding (within minutes) crystalline ZIF films with thickness down to that of a single structural building unit (2 nm). The film crystallized on graphene has a rigid aperture made of a six-membered zinc imidazolate coordination ring, enabling high-permselective H2 separation performance. The method reported here will probably accelerate the development of two-dimensional metal-organic framework films for efficient membrane separation.

8.
Adv Mater ; 34(51): e2206627, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36271513

RESUMO

Generating pores in graphene by decoupled nucleation and expansion is desired to achieve a fine control over the porosity, and is desired to advance several applications. Herein, epoxidation is introduced, which is the formation of nanosized epoxy clusters on the graphitic lattice as nucleation sites without forming pores. In situ gasification of clusters inside a transmission electron microscope shows that pores are generated precisely at the site of the clusters by surpassing an energy barrier of 1.3 eV. Binding energy predictions using ab initio calculations combined with the cluster nucleation theory reveal the structure of the epoxy clusters and indicate that the critical cluster is an epoxy dimer. Finally, it is shown that the cluster gasification can be manipulated to form Å-scale pores which then effectively sieve gas molecules based on their size. This decoupled cluster nucleation and pore formation will likely pave the way for an independent control of pore size and density.

9.
Angew Chem Int Ed Engl ; 61(40): e202207457, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35906967

RESUMO

Poly(triazine imide) or PTI is an ordered graphitic carbon nitride hosting Å-scale pores attractive for selective molecular transport. AA'-stacked PTI layers are synthesized by ionothermal route during which ions occupy the framework and occlude the pores. Synthesis of ion-free PTI hosting AB-stacked layers has been reported, however, pores in this configuration are blocked by the neighboring layer. The unavailability of open pore limits application of PTI in molecular transport. Herein, we demonstrate acid treatment for ion depletion which maintains AA' stacking and results in open pore structure. We provide first direct evidence of ion-depleted open pores by imaging with the atomic resolution using integrated differential phase-contrast scanning transmission electron microscopy. Depending on the extent of ion-exchange, AA' stacking with open channels and AB stacking with closed channels are obtained and imaged for the first time. The accessibility of open channels is demonstrated by enhanced proton transport through ion depleted PTI.

10.
ACS Nano ; 15(8): 13230-13239, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34319081

RESUMO

Predictable and tunable etching of angstrom-scale nanopores in single-layer graphene (SLG) can allow one to realize high-performance gas separation even from similar-sized molecules. We advance toward this goal by developing two etching regimes for SLG where the incorporation of angstrom-scale vacancy defects can be controlled. We screen several exposure profiles for the etchant, controlled by a multipulse millisecond treatment, using a mathematical model predicting the nucleation and pore expansion rates. The screened profiles yield a narrow pore-size-distribution (PSD) with a majority of defects smaller than missing 16 carbon atoms, suitable for CO2/N2 separation, attributing to the reduced pore expansion rate at a high pore density. Resulting nanoporous SLG (N-SLG) membranes yield attractive CO2 permeance of 4400 ± 2070 GPU and CO2/N2 selectivity of 33.4 ± 7.9. In the second etching regime, by limiting the supply of the etchant, the nanopores are allowed to expand while suppressing the nucleation events. Extremely attractive carbon capture performance marked with CO2 permeance of 8730 GPU, and CO2/N2 selectivity of 33.4 is obtained when CO2-selective polymeric chains are functionalized on the expanded nanopores. We show that the etching strategy is uniform and scalable by successfully fabricating high-performance centimeter-scale membrane.

11.
Chemistry ; 26(19): 4204-4208, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31944445

RESUMO

Multiple-stimuli-responsive photoluminescence films based on a ZnII -organic framework, {[Zn2 (Htpim)(3,4-pydc)2 ]⋅4 DMF⋅4 H2 O}n (1, Htpim=2,4,5-tri(4-pyridyl)imidazole, 3,4-H2 pydc=3,4-pyridinedicarboxylic acid), were fabricated. This compound consisted of a 2D corrugated layer, {Zn(3,4-pydc)}n , which was further pillared using a Y-shaped pillar N-donor ligand (Htpim) to form a 3D-pillared-layer framework with 1D open channels. The rectangular channels in the as-synthesized compound are fully occupied by guest DMF and H2 O molecules. The framework exhibits instant and reversible thermochromic properties corresponding to the removal of different H2 O and DMF guest molecules as temperature increases. The pale-yellow crystal undergoes significant redshifting to a greenish emission centered at 530 nm. Compound 1 also showed remarkable solvatochromic effects in the presence of various organic solvents without affecting its structural integrity. In addition, polycrystalline MOF films were grown on an α-Al2 O3 support for switchable and fast-response thermochromic and solvatochromic sensors.

12.
ACS Appl Mater Interfaces ; 10(1): 900-908, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29211438

RESUMO

Zeolites are ideal low-dielectric constant (low-k) materials. This paper reports on a novel plasma-assisted approach to the synthesis of low-k thin films comprising pure-silica zeolite MFI. The proposed method involves treating the aged solution using an atmospheric pressure plasma jet (APPJ). The high reactivity of the resulting nitrogen plasma helps to produce zeolite crystals with high crystallinity and uniform crystal size distribution. The APPJ treatment also remarkably reduces the time for hydrothermal reaction. The zeolite MFI suspensions synthesized with the APPJ treatment are used for the wet deposition to form thin films. The deposited zeolite thin films possessed dense morphology and high crystallinity, which overcome the trade-off between crystallinity and film quality. Zeolite thin films synthesized using the proposed APPJ treatment achieve low leakage current (on the order of 10-8 A/cm2) and high Young's modulus (12 GPa), outperforming the control sample synthesized without plasma treatment. The dielectric constant of our zeolite thin films was as low as 1.41. The overall performance of the low-k thin films synthesized with the APPJ treatment far exceed existing low-k films comprising pure-silica MFI.

13.
Nanoscale ; 8(40): 17427-17432, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27722401

RESUMO

Nanotube-based ultra-low-k thin films with high Young's modulus composed of single-walled aluminosilicate nanotubes (AlSiNTs) and a trace amount of poly(vinyl alcohol) (PVA) have been developed. The dehydrated AlSiNT film possesses a relative permittivity of 1.05, and a Young's modulus of 25 GPa, which exceed those of most existing ultra-low-k materials.

14.
IEEE Trans Image Process ; 23(3): 1047-59, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24474374

RESUMO

Camera-enabled mobile devices are commonly used as interaction platforms for linking the user's virtual and physical worlds in numerous research and commercial applications, such as serving an augmented reality interface for mobile information retrieval. The various application scenarios give rise to a key technique of daily life visual object recognition. On-premise signs (OPSs), a popular form of commercial advertising, are widely used in our living life. The OPSs often exhibit great visual diversity (e.g., appearing in arbitrary size), accompanied with complex environmental conditions (e.g., foreground and background clutter). Observing that such real-world characteristics are lacking in most of the existing image data sets, in this paper, we first proposed an OPS data set, namely OPS-62, in which totally 4649 OPS images of 62 different businesses are collected from Google's Street View. Further, for addressing the problem of real-world OPS learning and recognition, we developed a probabilistic framework based on the distributional clustering, in which we proposed to exploit the distributional information of each visual feature (the distribution of its associated OPS labels) as a reliable selection criterion for building discriminative OPS models. Experiments on the OPS-62 data set demonstrated the outperformance of our approach over the state-of-the-art probabilistic latent semantic analysis models for more accurate recognitions and less false alarms, with a significant 151.28% relative improvement in the average recognition rate. Meanwhile, our approach is simple, linear, and can be executed in a parallel fashion, making it practical and scalable for large-scale multimedia applications.


Assuntos
Algoritmos , Inteligência Artificial , Interpretação de Imagem Assistida por Computador/métodos , Diretórios de Sinalização e Localização , Processamento de Linguagem Natural , Reconhecimento Automatizado de Padrão/métodos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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