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1.
Am J Nephrol ; 54(1-2): 35-41, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996785

RESUMO

INTRODUCTION: Chronic kidney disease is estimated to become the fifth leading cause of death globally by 2040. Due to the high incidence of fatigue in patients with end-stage renal disease without reliable pharmacological treatments, more and more studies on non-pharmacological interventions to improve physical function appear; which might be the best approach remains unknown. This study aimed to compare and rank the efficacy of all known non-pharmacological interventions on improving physical function from multiple outcomes for adults with end-stage renal disease. METHODS: This systematic review and network meta-analysis included searches of PubMed, Embase, CINAHL, and Cochrane Library from inception to September 1, 2022, for randomized controlled trials of non-pharmacological interventions to improve physical function in adults with end-stage renal disease. Literature screening, data extraction, and quality appraisal were performed systematically by two independent reviewers. The frequentist random-effect network meta-analysis was adopted to pool the evidence from five outcomes, namely, 6-min walk test, handgrip strength, knee extension strength, physical component summary, and mental component summary, respectively. RESULTS: A total of 1,921 citations were identified by this search, of which 44 eligible trials enrolled 2,250 participants, and 16 interventions were identified. All subsequent figures refer to comparisons with usual care. For increasing walking distance, the combined resistance and aerobic exercise with virtual reality or music were the most effective interventions, with a mean difference plus 95% confidence interval of 90.69 (8.92-172.46) and 92.59 (23.13-162.06), respectively. Resistance exercise with blood flow restriction (8.13, 0.09-16.17) was the best treatment to improve handgrip strength. Combined resistance and aerobic exercise (11.93, 3.63-20.29) and whole-body vibration (6.46, 1.71-11.20) were associated with improving knee extension strength. For life quality, all treatment effects did not show statistically significant differences. CONCLUSIONS: It was found via network meta-analysis that combined resistance and aerobic exercise is the most effective intervention. Besides, if virtual reality or music is added to the training, there will be better results. Resistance exercise with blood flow restriction and whole-body vibration might be good alternative treatments for improving muscle strength. None of the interventions improved quality of life, suggesting a need for alternative interventions in this regard. The results of this study contribute evidence-based data to decision-making.


Assuntos
Força da Mão , Falência Renal Crônica , Adulto , Humanos , Qualidade de Vida , Metanálise em Rede , Exercício Físico , Falência Renal Crônica/terapia
2.
BMC Musculoskelet Disord ; 23(1): 1050, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460993

RESUMO

BACKGROUND: Chronic low back pain is a common musculoskeletal disease. With the increasing number of patients, it has become a huge economic and social burden. It is urgent to relieve the burden of patients. There are many common rehabilitation methods, and aquatic physical therapy is one of them. The purpose of this systematic review and meta-analysis is to summarize the existing literature and analyze the impact of aquatic physical therapy on pain intensity, quality of life and disability of patients with chronic low back pain. METHODS: Through 8 databases, we searched randomized controlled trials on the effect of aquatic physical therapy on patients with chronic low back pain. These trials published results on pain intensity, quality of life, and disability. This review is guided by Cochrane Handbook for systematic reviews of interventions version 5.1.0. The level of evidence was assessed through GRADE. RESULTS: A total of 13 articles involving 597 patients were included. The results showed that compared with the control group, aquatic physical therapy alleviated the pain intensity (Visual Analogue Scale: SMD = -0.68, 95%CI:-0.91 to -0.46, Z = 5.92, P < 0.00001) and improved quality of life (physical components of 36-Item Short Form Health Survey or Short-Form 12: SMD = 0.63, 95%CI:0.36 to 0.90, Ζ = 4.57, P < 0.00001; mental components of 36-Item Short Form Health Survey or Short-Form 12: SMD = 0.59, 95%CI:0.10 to 1.08, Ζ = 2.35, P = 0.02), and reduced disability (Roland Morris Disability Questionnaire: SMD = -0.42, 95%CI:-0.66 to -0.17, Ζ = 3.34, P = 0.0008; Oswestry Disability Index or Oswestry Low Back Pain Disability Questionnaire: SMD = -0.54, 95%CI:-1.07 to -0.01, Ζ = 1.99, P = 0.05). However, aquatic physical therapy did not improve patients' pain at rest (Visual Analogue Scale at rest: SMD = -0.60, 95%CI:-1.42 to 0.23, Ζ = 1.41, P = 0.16). We found very low or low evidence of effects of aquatic physical therapy on pain intensity, quality of life, and disability in patients with chronic low back pain compared with no aquatic physical therapy. CONCLUSIONS: Our systematic review showed that aquatic physical therapy could benefit patients with chronic low back pain. However, because the articles included in this systematic review have high bias risk or are unclear, more high-quality randomized controlled trials are needed to verify.


Assuntos
Dor Lombar , Humanos , Dor Lombar/diagnóstico , Dor Lombar/terapia , Qualidade de Vida , Modalidades de Fisioterapia , Exame Físico , Medição da Dor
3.
Virol J ; 14(1): 141, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28747230

RESUMO

BACKGROUND: Enzootic nasal tumor virus (ENTV) is a betaretrovirus of sheep (ENTV-1) and goats (ENTV-2) associated with neoplastic transformation of epithelial cells of the ethmoid turbinate. Confirmation of the role of ENTV in the pathogenesis of enzootic nasal adenocarcinoma (ENA) has yet to be resolved due to the inability to culture the virus. Very little is known about the prevalence of this disease, particularly in China. METHODS: To evaluate the genetic diversity of ENTV-2 from Shaanxi province of China, the complete genome sequence of four isolates from Shaanxi province was determined by RT-PCR. These sequences were analyzed to evaluate their genetic relatedness with other small ruminant betaretroviruses. Phylogenetic analyses based on the gag gene and env gene were performed. RESULTS: The ENTV-2-Shaanxi1 genome shared 97.0% sequence identity with ENTV-2-SC (accession number HM104174.1), and 89.6% sequence identity with the ENTV-2 sequences (accession number AY197548.1). ENTV-2 is closely related to the ENTV-1 and jaagsiekte retrovirus (JSRV). The main sequence differences between these viruses reside in LTR, two small regions of Gag, Orf-x, and the transmembrane (TM) region of Env. A stretch of 6 consecutive proline residues exists in VR1 of the ENTV-2-Shaanxi1 ~ 4 isolates. All the ENTV-2-Shaanxi isolates have the YXXM motif in the cytoplasmic tail of the Env. Phylogenetic analysis by nucleotide sequences showed that ENTV-2-Shaanxi1 ~ 4 isolates were closest related to two ENTV-2 isolates published in NCBI, especially with ENTV-2-SC strain. CONCLUSIONS: This finding indicates that ENA most likely was introduced to Shaanxi province by the movement of contaminated goats from other areas in China. This study adds to understand the circulation, variation and distribution of ENTV-2, and may prove beneficial in future control or eradication programmes.


Assuntos
Adenocarcinoma/veterinária , Betaretrovirus/genética , Betaretrovirus/isolamento & purificação , Variação Genética , Doenças das Cabras/virologia , Neoplasias Nasais/veterinária , Infecções Tumorais por Vírus/veterinária , Adenocarcinoma/virologia , Animais , Betaretrovirus/classificação , China , Cabras , Neoplasias Nasais/virologia , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Infecções Tumorais por Vírus/virologia , Sequenciamento Completo do Genoma
4.
Discov Oncol ; 15(1): 143, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704809

RESUMO

PURPOSE: Pancreatic cancer (PC) is one of the most lethal malignant gastrointestinal tumors (GI) characterized by a poor prognosis. Ferroptosis is an emerging programmed cell death that plays an essential role in the progression of various cancers. Ferroptosis is driven by iron-dependent phospholipid peroxidation and is regulated by mitochondrial activity, lipid peroxidation, and reactive oxygen species (ROS). The function and mechanism of ferroptosis in PC need more research. METHODS: The levels of circRNAs, miRNAs, and mRNAs were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was used for protein detection. CCK8 assays were used to detect cell proliferation. Cell death, lipid peroxidation, ROS, and Fe2+ were detected by indicted kits. Dual-luciferase reporter and RNA pull-down assays were conducted to confirm the interaction between circRNAs, miRNAs, and mRNAs. RESULTS: In this research, we found that circular RNA hsa_circ_0000003(circ_WASF2) was upregulated in pancreatic cancer cells. The silence of circ_WASF2 inhibited cancer proliferation and increased cell death by increasing ferroptosis accompanied by up-regulation of lipid peroxidation, ROS, and Fe2+. Further studies showed that circ_WASF2 could attenuate ferroptosis by targeting miR-634 and the downstream glutathione peroxidase 4 (GPX4). GPX4 has been well-reported as a central factor in ferroptosis. Our research revealed a new pathway for regulating ferroptosis in PC. CONCLUSION: In summary, we have determined that circ_WASF2/miR-634/GPX4 contributed to ferroptosis-induced cell death, and provided a possible therapeutic target in PC.

5.
ACS Appl Mater Interfaces ; 16(28): 36471-36478, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38955805

RESUMO

In the development of back electrodes for perovskite solar cells (PSCs), the major challenges are stability and cost. To address this, we present an innovative approach: Simultaneous evaporation of two independently controlled sources of metal materials was performed to achieve a uniform distribution of the alloy electrodes. In this study, Ag-Cu alloys (the molar ratio of Ag/Cu is 7/3) with a high-index crystal face (111) and a work function matching perovskite were prepared using a codeposition technique. These properties mitigate nonradiative carrier recombination at the interface and reduce the energy barrier for carrier migration. Consequently, compared to Ag based PSCs (22.77%), the implementation of Ag-Cu alloy (Ag/Cu is 7/3)-based PSCs resulted in a power conversion efficiency of 23.72%. In a 1500 h tracking test in ambient air, the Ag-Cu alloy (Ag/Cu is 7/3)-based PSCs maintained their initial efficiency of 86%. This can be attributed to almost no migration of elements from the Ag-Cu alloy electrode to the perovskite layer. Our work presents a vital strategy for improving the stability of PSCs and reducing the costs associated with the back electrode in PSCs.

6.
Natl Sci Rev ; 11(4): nwae026, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38405434

RESUMO

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering (LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys (RHEAs). In contrast to conventional 'trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength (1160 MPa) and uniform ductility (24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

7.
Mar Pollut Bull ; 194(Pt A): 115411, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37595334

RESUMO

The Yangtze River ships are generally overpowered and less energy efficient. In this study, a Yangtze ship was selected as the test ship, and its characteristics were investigated through energy consumption and emission testing under multiple operating conditions. The results show that the ship operates at 25-50 % engine load for 72.2 % of the time, and at this partial load, 9.72 % more CO2 and 9.81 % more NOX can be emitted than at the rated power. The concentrations of exhaust vary under different operating conditions. The emission factor of CO was the highest under departure conditions; CO2 and SO2 were the highest under anchoring conditions; and NOx was the highest under cruising conditions. The accuracy of the emission factors obtained by the direct calculation method was improved by 30 % compared to the concentration estimation method. This study can help understand the real level of energy consumption and emissions from in-service ships.


Assuntos
Dióxido de Carbono , Navios , Fenômenos Físicos , Rios
8.
Chem Commun (Camb) ; 60(1): 122-125, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38038120

RESUMO

Mesoporous Pt-based alloy nanospheres were prepared via a one-step soft-template strategy. The regulation of electronic structure, lattice contraction and abundant active sites endowed the mesoporous Pt-based catalysts with remarkable electrochemical activity towards ethanol oxidation reaction.

9.
RSC Adv ; 11(31): 19136-19146, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35478626

RESUMO

MnO2 coatings prepared in a sulfate system (S-MnO2) and MnO2 prepared in a nitrate system (N-MnO2) were successfully deposited on porous Ti/Sn-Sb-RuO x /ß-PbO2 substrates by electrodeposition, and their electrochemical properties were studied in detail. The bath composition plays a very important role in the MnO2 coating prepared by electrodeposition at a low current density. The results of scanning electron microscopy show that a Ti/Sn-Sb-RuO x /ß-PbO2/MnO2 electrode has a rough morphology and the unit cell is very good. At the same time, the surface cracks in the S-MnO2 coating are larger than those in the N-MnO2 coating. In addition, the N-MnO2 coating is composed of a fluffy sheet-like substance. The surface morphology of the N-MnO2 coating is denser than that of the S-MnO2 coating. The S-MnO2 coating consists of irregularly stacked granular particles. Further, the main crystal phase of MnO2 is γ type, and the main valence state of MnO2 is +4. The results show that the oxygen evolution potential of the N-MnO2 electrode is 63 mV lower than that of the S-MnO2 electrode, indicating that the N-MnO2 electrode has better oxygen evolution activity and electrochemical stability, which can also be confirmed by EIS test results. Under the accelerated life test conditions, the N-MnO2 electrode has a better service life of 77 h at a current density of 1 A cm-2 in 150 g L-1 H2SO4 and 2 g L-1 Cl- solution.

10.
Front Microbiol ; 12: 593202, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33584608

RESUMO

Infection with H5N6 highly pathogenic avian influenza virus caused high mortality in chickens, while ducks often appear to be asymptomatic. But, some recent H5Nx subtype viruses could cause high mortality in ducks. The variation between different species and the mechanisms by which some H5Nx viruses cause death in ducks requires investigation to identify the key processes in influenza susceptibility and pathogenesis. Here, we characterized two representative H5N6 viruses, A/Pavo cristatus/Jiangxi/JA1/2016 (JA1) and A/Anas crecca/shanghai/SH1/2016 (SH1), and compared their pathogenicity and expression profiles of immune-related genes in chickens and ducks to identify the elements of the host immune-related response that were involved in disease lethality. Results suggested that H5N6 HPAIVs had higher pathogenic and inflammatory effect in chickens than in ducks. Importantly, the TNF-α, IL-6, IFN-γ and iNOS levels were significantly higher in the lung of SH1 infected chickens compared to those of ducks. And we found higher systemic levels of IL-6 induced by JA1 in chickens than in ducks. In addition, our experiments demonstrated that JA1 was associated with greater pathogenicity in ducks were accompanied by the excessive expression of iNOS in the brain. These results are helpful to understand the relationship between the pathogenicity of H5N6 AIVs and inflammatory responses to them in chickens and ducks.

12.
Dalton Trans ; 47(27): 9072-9078, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29932204

RESUMO

We report the design and realization of yolk-shell structured nanospheres with periodic mesoporous organosilica (PMO) nanospheres or noble metal nanoparticles encapsulated in mesoporous silica shells via a selective etching method. These architectures have well controlled structure, size and morphology. The yolk-shell structured PMO@SiO2 nanoparticles can be precisely functionalized with different catalytic functionalities, even incompatible acidic and basic groups: the PMO core with amino (-NH2) groups and the mesoporous silica shell with sulfonic acid (-SO3H) groups. As a nanoreactor, the as-synthesized Au@SiO2 nanospheres show faster reduction of 4-nitrophenol than that of nitrobenzene. Furthermore, the prepared PMO-NH2@SiO2-SO3H nanoparticles can be used as bifunctional catalysts with highly efficient catalytic performance for catalyzing the deacetalization-Henry cascade reaction.


Assuntos
Catálise , Nanopartículas Metálicas/química , Nanosferas/química , Dióxido de Silício/química , Ouro/química , Microscopia Eletrônica de Transmissão , Nitrobenzenos/química , Nitrofenóis/química , Compostos Organoáuricos/síntese química , Compostos Organoáuricos/química , Tamanho da Partícula , Porosidade , Ácidos Sulfônicos/química , Água/química
13.
Chemosphere ; 193: 89-99, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29127839

RESUMO

A hydrophobic networked PbO2 electrode was deposited on mesh titanium substrate and utilized for the electrochemical elimination towards paracetamol drug. Three dimensional growth mechanism of PbO2 layer provided more loading capacity of active materials and network structure greatly reduced the mass transfer for the electrochemical degradation. The active electrochemical surface area based on voltammetric charge quantity of networked PbO2 electrode is about 2.1 times for traditional PbO2 electrode while lower charge transfer resistance (6.78 Ω cm2) could be achieved on networked PbO2 electrode. The electrochemical incineration kinetics of paracetamol drug followed a pseudo first-order behavior and the corresponding rate constant were 0.354, 0.658 and 0.880 h-1 for traditional, networked PbO2 and boron doped diamond electrode. Higher electrochemical elimination kinetics could be achieved on networked PbO2 electrode and the performance can be equal to boron doped diamond electrode in result. Based on the quantification of reactive oxidants (hydroxyl radicals), the utilization rate of hydroxyl radicals could reach as high as 90% on networked PbO2 electrode. The enhancement of excellent electrochemical oxidation capacity towards paracetamol drug was related to the properties of higher loading capacity, enhanced mass transfer and hydrophobic surface. The possible degradation mechanism and pathway of paracetamol on networked PbO2 electrode were proposed in details accordingly based on the intermediate products.


Assuntos
Acetaminofen/química , Técnicas Eletroquímicas , Eletrodos , Chumbo/química , Oxirredução , Óxidos/química , Poluentes Químicos da Água/química , Boro/química , Diamante/química , Eletroquímica/métodos , Interações Hidrofóbicas e Hidrofílicas , Radical Hidroxila , Incineração , Cinética , Modelos Químicos , Titânio/química
14.
J Colloid Interface Sci ; 530: 338-344, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29982026

RESUMO

The porous carbon with angstrom-sized pores is important in supercapacitor applications, because of its high pack density and high specific capacitance. In this paper, a facile method is proposed for the preparation of hierarchical porous carbon with high-volume angstrom-sized pores. Onion, as the typical biomass in this research, is used as carbon precursor. First, onion was etched by KOH to obtain a water-soluble lignin-potassium-salt/cellulose composite. This composite was further pyrolyzed under N2 atmosphere to obtain onion derived porous carbon (OPC). The morphology and porous structure of OPC were characterized by scanning electron microscope and N2 adsorption/desorption. The supercapacitive performances of OPC were investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge-discharge. OPC shows high specific surface area with high-volume angstrom-sized pores in carbon matrix. When used as supercapacitor electrode materials, OPC shows high specific capacitance and good cycling stability. This paper opens a general way to prepare porous carbon from biomasses, which will promote the development of biomass utilization, preparation of porous carbon and supercapacitors.


Assuntos
Carbono/química , Celulose/química , Capacitância Elétrica , Lignina/química , Cebolas/química , Adsorção , Biomassa , Eletrodos , Calefação , Hidróxidos/química , Nitrogênio/química , Porosidade , Compostos de Potássio/química
15.
J Virol Methods ; 243: 44-49, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28111057

RESUMO

Multiplex reverse transcription-polymerase chain reaction (RT-PCR) and PCR protocols were developed and subsequently evaluated for its effectiveness in detecting simultaneously single and mixed infections in sheep and goats. Specific primers for three DNA viruses and three RNA viruses, including foot and mouth disease virus (FMDV), Bluetongue virus (BTV), peste des petits ruminants virus (PPRV), sheeppox virus (SPPV), goatpox virus (GTPV) and orf virus (ORFV) were used for testing procedure. A single nucleic acid extraction protocol was adopted for the simultaneous extraction of both RNA and DNA viruses. The multiplex PCR consisted with two-step procedure which included reverse transcription of RNA virus and multiplex PCR of viral cDNA and DNA. The multiplex PCR assay was shown to be sensitive because it could detect at least 100pg of viral genomic DNA or RNA from a mixture of six viruses in a reaction. The assay was also highly specific in detecting one or more of the same viruses in various combinations in specimens. Thirty seven clinical samples collected from sheep and goats were detected among forty three samples tested by both uniplex and multiplex PCR, showing highly identification. As results of the sensitivity and specificity, the multiplex PCR is a useful approach for clinical diagnosis of mixed infections of DNA and RNA viruses in sheep and goats with a reaction.


Assuntos
Vírus de DNA/isolamento & purificação , Doenças das Cabras/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Vírus de RNA/isolamento & purificação , Doenças dos Ovinos/diagnóstico , Viroses/veterinária , Animais , Vírus de DNA/classificação , Vírus de DNA/genética , Doenças das Cabras/virologia , Cabras , Vírus de RNA/classificação , Vírus de RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/virologia , Viroses/virologia
16.
Front Immunol ; 8: 1757, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312300

RESUMO

Influenza A viruses (IAVs) take advantage of the host acetylation system for their own benefit. Whether the nucleoprotein (NP) of IAVs undergoes acetylation and the interaction between the NP and the class I histone deacetylases (HDACs) were largely unknown. Here, we showed that the NP protein of IAV interacted with HDAC1, which downregulated the acetylation level of NP. Using mass spectrometry, we identified lysine 103 as an acetylation site of the NP. Compared with wild-type protein, two K103 NP mutants, K103A and K103R, enhanced replication efficiency of the recombinant viruses in vitro. We further demonstrated that HDAC1 facilitated viral replication via two paths: promoting the nuclear retention of NP and inhibiting TBK1-IRF3 pathway. Our results lead to a new mechanism for regulating NP acetylation, indicating that HDAC1 may be a possible target for antiviral drugs.

17.
Chem Commun (Camb) ; 52(51): 8026-9, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27264247

RESUMO

A boron-doped diamond electrode with a three-dimensional network was fabricated on a mesh titanium substrate. Properties such as higher surface area, enhanced mass transfer and a hydrophobic surface endowed the prepared electrode with excellent electrochemical oxidation ability towards contaminants.

18.
Nanoscale ; 8(28): 13581-8, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27341315

RESUMO

We describe a facile and controllable asymmetrical/symmetrical coating strategy for the preparation of various novel periodic mesoporous organosilica (PMO) nanostructures, including Au&PMO Janus, Au@PMO yolk-shell and Au@PMO/mSiO2 yolk-double shell nanoparticles, by using Au@SiO2 nanoparticles as seeds. During this process, ammonia first functions as a basic catalyst facilitating the hydrolyzation and condensation of the organosilica precursor, and additionally as an etching agent selectively in situ dissolving the SiO2 shells of Au@SiO2 nanoparticles to form these unique nanostructures. All these three types of nanoparticles have high surface areas, large pore volumes and tailorable cavity structures. Both the Au&PMO and Au@PMO nanoparticles exhibit excellent catalytic activity for the decomposition of H2O2 and the reduction of 4-nitrophenol. Based on these unique structural merits and organic-inorganic hybrid components, the fabricated Janus and hollow PMO nanoparticles show much improved hemocompatibility, which could be further applied in nano-biomedicines without the need for surface modification.

19.
Nanoscale ; 7(8): 3719-25, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25640736

RESUMO

Megranate-like nanoparticles possess a unique structure that is composed of multiple cores and shells, which is different from simple yolk-shell nanoparticles. Megranate-like nanoparticles can combine the properties of each component and be used as nanoreactors. This study describes the preparation of bifunctional megranate-like nanoreactors, consisting of multiple metal cores and thiol modified mesoporous SiO2 shells. Different metal nanoparticles (Pd, Pt, Au) can be incorporated into the structure as cores, and the thiol group in the shells can be oxidized to acidic -SO3H. The megranate-like nanoparticles show good bifunctional catalytic properties and recyclability in a cascade catalytic reaction for the desired benzimidazole derivative. Moreover, the individual components of the megranate-like nanoparticles also show good catalytic activities in the hydrogenation reduction of nitro-aromatics and the deprotection reaction of benzaldehyde dimethyl acetal.

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