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1.
Phytother Res ; 37(9): 4265-4281, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37260161

RESUMO

Sanguisorba officinalis L., a traditional Chinese medicine, is frequently used to treat burns and scalds. But even so, it is unknown whether S. officinalis L. can accelerate diabetic wounds (DW) healing. Here, to bridge the gap, we employed in vivo and in vitro evaluations to assess the positive effect of S. officinalis L. ethanol extract (ESO) on DW. Results demonstrated that ESO dramatically improved the DW healing rate. With ESO treatment, the inappropriately elevated levels of IL6, IL1ß and TNFα in DW were reduced, while the expression of IL10 was increased, indicating that the abnormal inflammation in DW was also under control. Moreover, the abnormally elevated expression of CD86 was significantly inhibited and the expression of CD206 was significantly up-regulated following treatment with ESO. The global level of NF-κB protein was not affected by ESO treatment, but it suppressed the expression of phosphorylated NF-κB and prevented its nuclear entry. In addition, in RAW264.7 cells activated with lipopolysaccharide (LPS), the expression of NLRP3, Caspase1 and IL1ß were significantly diminished following ESO treatment. In conclusion, ESO was proved to be a promising treatment for DW healing due to its potential to accelerate the healing process by suppressing the inflammatory response. This was achieved by increasing the ratio of M2 to M1 polarization through blocking the NF-κB/NLRP3 signaling pathway.


Assuntos
Queimaduras , Diabetes Mellitus , Sanguisorba , Ratos , Animais , NF-kappa B/metabolismo , Sanguisorba/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Cicatrização , Macrófagos , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia
2.
Front Biosci (Landmark Ed) ; 27(10): 285, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36336859

RESUMO

Difficult or even non-healing diabetic foot ulcers (DFU) are a global medical challenge. Although current treatments such as debridement, offloading, and infection control have resulted in partial improvement in DFU, the incidence, amputation, and mortality rates of DFU remain high. Therefore, there is an urgent need to find new or more effective drugs. Numerous studies have shown that oxidative stress plays an important role in the pathophysiology of DFU. The nuclear factor erythroid 2-related factor (Nrf2) signaling pathway and the advanced glycated end products (AGEs)-receptor for advanced glycation endproducts (RAGE), protein kinase C (PKC), polyol and hexosamine biochemical pathways play critical roles in the regulation of oxidative stress in the body. Targeting these pathways to restore redox balance can control and alleviate the occurrence and development of DFU. Natural biologics are a major source of potential drugs for these relevant targets, and their antioxidant potential has been extensively demonstrated. Here, we discussed the pathophysiological mechanism of oxidative stress in DFU, and identifiled natural biologics targeting these pathways to accelerate DFU healing, in order to provide a new or potential direction for clinical treatment, nursing and related basic research of DFU.


Assuntos
Produtos Biológicos , Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/tratamento farmacológico , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Cicatrização , Estresse Oxidativo
3.
Sensors (Basel) ; 22(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35632230

RESUMO

The continuous phase modulation (CPM) technique is an excellent solution for underwater acoustic (UWA) channels with limited bandwidth and high propagation attenuation. However, the severe intersymbol interference is a big problem for the algorithm applying in shallow water. To solve this problem, an algorithm for prefiltered single-carrier frequency-domain equalization (PF-SCFDE) is presented in this paper. The regular whitening filter is replaced by a prefilter in the proposed algorithm. The output information sequence of this prefilter contains the forward information. To improve the performance, the output of the equalizer, combined with the forward information, is used to make the maximum likelihood estimation. The simulation results with minimum-shift keying and Gaussian-filtered minimum-shift keying signals over shallow water acoustic channels with low root mean square delay spread demonstrate that PF-SCFDE outperformed the traditional single-carrier frequency-domain equalization (SCFDE) by approximately 1 dB under a bit error rate (BER) of 10-4. A shallow sea trial has demonstrated the effectiveness of PF-SCFDE; PF-SCFDE had a reduction in BER of 18.35% as compared to the traditional SCFDE.

4.
J Acoust Soc Am ; 142(4): 1848, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29092563

RESUMO

The waveguide invariant ß is typically discussed in terms of either a range-independent environment or a range-dependent environment under the adiabatic approximation, with few studies considering the effects of mode coupling. In this work, how internal solitary waves (ISWs) affect the waveguide invariant is investigated, and it is shown that mode-coupling effects introduce many additional components in the acoustic interference intensity. It is found that the striation slope and value of ß for these additional components are determined not only by the acoustic modal dispersion, but are also dependent on the position where the mode coupling occurs. This can lead to a very complicated acoustic interference pattern and result in multiple peaks in the distribution of ß. The sensitivity of ß to the parameters of ISWs, such as amplitude, horizontal scale, and position, is analyzed. It is found that although all parameters can affect the energy of the peaks, only the position of the internal wave has an obvious impact on the peak values. This indicates that the peak values of ß can be utilized for monitoring the position of the internal wave.

5.
Langmuir ; 29(21): 6232-41, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23672308

RESUMO

Bottom-up self-assembly is able to constitute a variety of structures and has been thought to be a promising way for advanced nanofabrication. Droplet evaporation, as the simplest method, has been used in various self-assemblies. However, the assembled area is not large enough and the order is still not well controlled. Here we show a facile and controllable two-stage droplet evaporation method by adjusting the humidity and temperature of the evaporating droplet. Taking the highly monodispersed gold nanorods (GNRs) as an example, large-area, self-assembly monolayer arrays are reproducibly achieved. To understand the self-assembly mechanism, we adopted simplified models to analyze the interactions between the nanorods. The results show that a metastable state of secondary-energy-minimum exists, especially in the latter stage of the assembly process, leading to the ordered arrays. A large electrostatic barrier between the assembled arrays prevents the formation of the multilayer structures and thereby leads to the preferential monolayers. Moreover, we predict possibilities of different types of assemblies of the nanorods, and a schematic phase diagram is finally given. The results here may offer a way toward high-quality self-assembled nanoparticles superlattices for use in enhanced spectroscopy, sensors, or nanodevices.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Tamanho da Partícula , Propriedades de Superfície , Volatilização
6.
J Nanosci Nanotechnol ; 13(2): 776-80, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23646514

RESUMO

Anisotropic nanostructures are becoming more and more attractive due to their unique properties different from isotropic nanostructures. However, previous most of studies are limited to high melting point materials with poor crystalline, which has confined their extended applications. In this work, we successfully prepared the anisotropic nano-column arrays of bismuth (melting point: 271.3 degrees C) with improved crystallinity by glancing angle deposition. The anisotropic conductivity of the products is investigated, and its origin is ascribed to the anisotropic scattering of the carriers in the boundary layer. Our work is not only helpful to understand the anisotropic nanostructures fabricated by glancing angle deposition on both their growth and properties, as well as provides an approachable route for constructing functional devices based on Bi and its anisotropic nanostructures.

7.
J Nanosci Nanotechnol ; 13(2): 829-33, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23646524

RESUMO

Ge1.5Sn0.5Sb2Te5 (GSST) can be easily induced to phase transition from amorphous state to crystalline state by a laser direct writing (LDW) system. The results show that the crystalline phase of GSST is more durable against acid solution corrosion than the amorphous phase. So nano-scale patterns and structures can be formed on the GSST film resists using laser-induced phase change and wet etching. Moreover, reactive ion etching (RIE) technology was applied to transfer these patterns onto the SiO2 substrate. The result shows to the extent that GSST material has thermal resist characteristics with high resolution and well etching selectivity to SiO2 when etched in the CHF3, which is compatibility with the future nanofabricate processing.

8.
J Nanosci Nanotechnol ; 13(2): 914-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23646541

RESUMO

The fascinating properties and wide applications of the V2O5 nanostructures have attracted significant attention over the past decades. In this paper, ultralong (centimeter-scale) single-crystal V2O5 nanobelts are successfully fabricated by modified chemical vapor deposition. The wide of the V2O5 nanobelts are 20-500 nm. The aspect ratio exceeds 10(5). The structure and crystal orientation of the nanobelts are investigated. X-ray diffractometer (XRD) patterns and Raman spectrum show the substrate temperature affecting the size and morphology of the V2O5 nanobelts. And the growth mechanism and electronic properties of the ultralong V2O5 nanobelt are studied in detail. The activation energy 0.12 eV is calculated. The fastest growth orientation along the [010] direction has been observed. Our work demonstrates that the single-crystal V2O5 nanobelt has potential applications in field-emitters, lithium-ion batteries, photodetectors, interconnect, and optoelectronic devices, etc.

9.
Genetica ; 140(7-9): 337-47, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23054225

RESUMO

Activator/Dissociation (Ac/Ds) transposable elements have been used in maize insertional mutagenesis as a complement to Mutator (Mu). In this study, to further improve the efficiency of the Ac/Ds mutagenesis system, we adopted apt1-m1 (Ac) on the long arm of chromosome 9 (9L) as a donor Ac to create an Ac insertion library. This system is based on the negative selection pressure against the donor Ac, and it was highly efficient for isolating new transposition events. We obtained 9,625 transposition events from 1083 F1 ears with an average transposition rate of 8.66 % (rates ranged from 1.11 to 29.73 %). We also adopted a modified PCR-based genome walking strategy to improve the efficiency of the new method for isolating transposon-flanking sequences. This method is more efficient than the Southern-based method that was used in previous studies. A validation step was developed to distinguish transposon tags derived from newly transposed Ac or Ds elements. Using this PCR-based method, we isolated 67 inheritable flanking sequences from the apt1-m1 (Ac) transposition library; of these, 51 were confirmed as tr-Ac-flanking sequences and 11 were tr-Ds-flanking sequences. Similar to other Ac donors from different loci, the apt1-m1 (Ac) system also exhibited a preference for short distance transposition. In this study, we have further improved the Ac mutagenesis system in maize for gene isolation and functional genomics studies.


Assuntos
Cromossomos de Plantas/genética , Elementos de DNA Transponíveis , Zea mays/genética , Sequência de Bases , DNA de Plantas/química , Genes de Plantas , Genoma de Planta , Dados de Sequência Molecular , Mutagênese Insercional , Reação em Cadeia da Polimerase
10.
Opt Express ; 20(7): 6974-9, 2012 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-22453376

RESUMO

A photoelectric switch with fast response to visible light (<200 µs), suitable photosensitivity and excellent repeatability is proposed based on the ultralong single crystalline V2O5 nanobelt, which are synthesized by chemical vapor deposition and its photoconductive mechanism can well be explained by small polaron hopping theory. Our results reveal that the switch has a great potential in next generation photodetectors and light-wave communications.


Assuntos
Eletrônica , Nanopartículas/química , Nanopartículas/ultraestrutura , Refratometria/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Vanádio/química , Vanádio/efeitos da radiação , Simulação por Computador , Desenho Assistido por Computador , Campos Eletromagnéticos , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Modelos Teóricos , Espalhamento de Radiação
11.
Chem Commun (Camb) ; 48(15): 2128-30, 2012 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-22245915

RESUMO

Real-time observations on gold nanorods evolving into spiral or lamellar superlattices are demonstrated. 2D critical nuclei and screw dislocations initiate the crystallization process. Kinetics of the superlattice growth is determined to be similar to that of classical crystal growth, where three basic modes are involved: spiral, layer-by-layer and dendritic.


Assuntos
Ouro/química , Nanotubos/química , Nanotubos/ultraestrutura , Cristalização , Nanotecnologia
12.
Langmuir ; 27(18): 11394-400, 2011 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-21830776

RESUMO

The self-assembly of anisotropic gold nanorods (GNRs) into ordered phases remains a challenge. Herein, we demonstrated the fabrication of symmetric circular- or semicircular-like self-assembled superlattices composed of multilayers of standing GNRs by fine-tuning the repulsive interactions among GNRs. The repulsive force is tailored from electrostatic interaction to steric force by replacing the surface coating of cetyltrimethylammonium bromide (CTAB) (ζ potential of 20-50 mV) with an OH-terminated hexa(ethylene glycol) alkanethiol (here termed as EG(6)OH, ζ potential of -10 mV). The assembly mechanism is discussed via theoretical analyses of the major interactions, and an effective balance between the repulsive steric and attractive depletion interactions is the main driving force for the self-assembly. The real-time observations of solution assembly (UV-vis-NIR absorption spectroscopy) supports the mechanism that we suggested. The superlattices obtained here not only enrich the categories of the self-assembled structures but more importantly deepen the insight of the self-assembly process and pave the way for various potential applications.


Assuntos
Ouro/química , Hidróxidos/química , Nanotubos/química , Polietilenoglicóis/química , Compostos de Sulfidrila/química , Análise Espectral Raman , Eletricidade Estática , Volatilização
13.
J Am Chem Soc ; 133(21): 8211-5, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21428287

RESUMO

Design and synthesis of super-nanostructures is one of the key and prominent topics in nanotechnology. Here we propose a novel methodology for synthesizing complex hierarchical superstructures using sacrificial templates composed of ordered two-dimensional (2D) nanostructures through lattice-directed topotactic transformations. The fabricated superstructures are nested 2D orthogonal Bi(2)S(3) networks composed of nanorods. Further investigation indicates that the lattice matching between the product and sacrificial template is the dominant mechanism for the formation of the superstructures, which agrees well with the simulation results based on an anisotropic nucleation and growth analysis. Our approach may provide a promising way toward a lattice-directed nonlithographic nanofabrication technique for making functional porous nanoarchitectures and electronic devices.

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