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1.
J Cell Mol Med ; 24(6): 3384-3398, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31981312

RESUMO

Recent studies have demonstrated that commercially available lipid-lowering drugs cause various side effects; therefore, searching for anti-hyperlipidaemic compounds with lower toxicity is a research hotspot. This study was designed to investigate whether the marine-derived compound, 5-hydroxy-3-methoxy-5-methyl-4-butylfuran-2(5H)-one, has an anti-hyperlipidaemic activity, and the potential underlying mechanism in vitro. Results showed that the furanone had weaker cytotoxicity compared to positive control drugs. In RAW 264.7 cells, the furanone significantly lowered ox-LDL-induced lipid accumulation (~50%), and its triglyceride (TG)-lowering effect was greater than that of liver X receptor (LXR) agonist T0901317. In addition, it significantly elevated the protein levels of peroxisome proliferator-activated receptors (PPARα) and ATP-binding cassette (ABC) transporters, which could be partially inhibited by LXR antagonists, GSK2033 and SR9243. In HepG2 cells, it significantly decreased oleic acid-induced lipid accumulation, enhanced the protein levels of low-density lipoprotein receptor (LDLR), ABCG5, ABCG8 and PPARα, and reduced the expression of sterol regulatory element-binding protein 2 (~32%). PPARα antagonists, GW6471 and MK886, could significantly inhibit the furanone-induced lipid-lowering effect. Furthermore, the furanone showed a significantly lower activity on the activation of the expression of lipogenic genes compared to T0901317. Taken together, the furanone exhibited a weak cytotoxicity but had powerful TC- and TG-lowering effects most likely through targeting LXRα and PPARα, respectively. These findings indicate that the furanone has a potential application for the treatment of dyslipidaemia.

2.
Taiwan J Obstet Gynecol ; 58(3): 332-337, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31122520

RESUMO

OBJECTIVE: To evaluate the efficacy and toxicity of VMP regimen applied to the patients with low-risk gestational trophoblastic neoplasia (LR-GTN) treated in Anhui provincial hospital. MATERIALS AND METHODS: Between 2005 and 2017, 87 patients with low-risk gestational trophoblastic neoplasia received VMP regimen, consisted of vincristine (VCR), methotrexate (MTX) and platinum (cisplatin, carboplatin or nedaplatin), 68 of whom received VMP as their first-line chemotherapy, and 19 methotrexate-failed patients received VMP regimen as their second-line chemotherapy. The staging and scoring system was based on International Federation of Gynecology and Obstetrics (FIGO 2000) criteria. We describe and analyze their baseline characteristics, remission/resistance/recurrence rates, adverse reactions and prognosis. RESULTS: The first-line VMP protocol can achieve an 83.8% remission rate and it tended to develop resistance when the pretreatment ß-hCG reaches 7503.5 IU/L, and can achieve complete remission with FAV and EMA-CO as the salvage regimen. Among the 19 methotrexate-failed patients, 2 of whom were yet resistant to VMP regimen, followed by several courses of salvage chemotherapy such as FAV and EMP, and achieved 89.5% remission rate in second-line VMP group. Resistance to this regimen was obviously related with higher pre-treatment HCG whether used as primary or salvage treatment. Severe myelosuppression (grade 3 or 4) was shown in 4 (5.9%) of 68 cases, of which none was grade 4. CONCLUSION: For patients diagnosed with LR-GTN VMP regimen was a safe and effective treatment with a high rate of remission.


Assuntos
Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Doença Trofoblástica Gestacional/tratamento farmacológico , Indução de Remissão/métodos , Adulto , Gonadotropina Coriônica Humana Subunidade beta/sangue , Cisplatino/administração & dosagem , Feminino , Humanos , Metotrexato/administração & dosagem , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Vincristina/administração & dosagem
3.
Chem Sci ; 8(4): 2952-2958, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28451361

RESUMO

Electrochemical water splitting into hydrogen and oxygen is a promising technology for sustainable energy storage. The development of earth-abundant transition metal phosphides (TMPs) to catalyze the hydrogen evolution reaction (HER) and TMP-derived oxy-hydroxides to catalyze the oxygen evolution reaction (OER) has recently drawn considerable attention. However, most monolithically integrated metal phosphide electrodes are prepared by laborious multi-step methods and their operational stability at high current densities has been rarely studied. Herein, we report a novel vapor-solid synthesis of single-crystalline cobalt phosphide nanowires (CoP NWs) on a porous Co foam and demonstrate their use in overall water splitting. The CoP NWs grown on the entire surface of the porous Co foam ligaments have a large aspect ratio, and hence are able to provide a large catalytically accessible surface over a given geometrical area. Comprehensive investigation shows that under the OER conditions CoP NWs are progressively and conformally converted to CoOOH through electrochemical in situ oxidation/dephosphorization; the latter serving as an active species to catalyze the OER. The in situ oxidized electrode shows exceptional electrocatalytic performance for the OER in 1.0 M KOH, delivering 100 mA cm-2 at an overpotential (η) of merely 300 mV and a small Tafel slope of 78 mV dec-1 as well as excellent stability at various current densities. Meanwhile, the CoP NW electrode exhibits superior catalytic activity for the HER in the same electrolyte, affording -100 mA cm-2 at η = 244 mV and showing outstanding stability. An alkaline electrolyzer composed of two symmetrical CoP NW electrodes can deliver 10 and 100 mA cm-2 at low cell voltages of 1.56 and 1.78 V, respectively. The CoP NW electrolyzer demonstrates exceptional long-term stability for overall water splitting, capable of working at 20 and 100 mA cm-2 for 1000 h without obvious degradation.

4.
Chem Commun (Camb) ; 52(24): 4481-4, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-26932785

RESUMO

Flowerlike WSe2 and WS2 microspheres were synthesized by a facile and scalable one-pot solvothermal method. Their formation mechanism followed the reaction between dissolved W(CO)6 and dissolved S or melted Se without complete decomposition of W(CO)6 into tungsten. As novel efficient sorbents, WSe2 and WS2 demonstrated outstanding uptake capacities for Pb(2+) and Hg(2+).

5.
J Nanosci Nanotechnol ; 15(9): 6628-35, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26716221

RESUMO

Series of catalysts made of Pt nanoparticles supported on reduced graphene oxides (Pt/RGO) were synthesized and tested in methanol oxidation reaction, aiming for optimizing the mass-specific activity of prepared Pt/RGO composites. The loading amount of Pt is controlled through setting different reaction time and determined precisely by atomic absorption spectrophotometer. The structure of Pt/RGO composites is characterized by X-ray diffraction, transmission electron microscopy and Raman spectroscopy. The electrochemical testing data reveal that the Pt/RGO-mass-specific activity, judged by current density and long-term stability, is maximized in the sample in which cooperation of the Pt loading amount and electrochemical active surface area (ECSA) per amount of Pt is best optimized. The performance of the catalyst with smallest Pt particles or highest Pt loading amount is dragged down by either too less Pt loading or poor ECSA per amount of Pt. The results in this research demonstrate that the mass-normalized activity of whole catalyst, which is associated with the anticipated power output per amount of catalyst, could be enhanced significantly by deliberate tuning of fabrication process.

6.
Nano Lett ; 15(5): 3088-95, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25929671

RESUMO

The key challenges in enhancing the power conversion efficiency (PCE) of a quantum dot-sensitized solar cell (QDSSC) are efficiently achieving charge separation at the photoanode and improving the charge transfer, which is limited by the interface between the electrolyte and the counter electrode (CE). Here, hierarchically assembled ITO@Cu2S nanowire arrays with conductive single-crystalline ITO cores and Cu2S nanocrystal shells were designed as efficient QDSSCs CEs. These arrays not only provided an efficient three-dimensional charge transport network but also allowed for the effective deposition of more Cu2S nanocrystals as active sites to catalyze the electrolyte reaction. This design considerably reduced the sheet and charge transfer resistance of the CE, thus decreasing the series resistance and increasing the shunt resistance of the QDSSC. As a result, QDSSCs with this CE exhibited an unprecedentedly high Voc of 0.688 V, a fill factor of 58.39%, and a PCE of 6.12%, which is 21.2% higher than that of the conventional brass/Cu2S CE.

7.
Chem Commun (Camb) ; 51(35): 7482-5, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25827909

RESUMO

Pd nanoparticles were successfully introduced into the channels of mesoporous silica MCM-41 with their dispersion well-tuned. We identified the dual role played by CTAB, which was critical for both the micelle template and Pd grafting, leading to the formation of a highly active Pd-MCM-41 nanocomposite for catalysing the Suzuki reaction.


Assuntos
Nanopartículas Metálicas/química , Nanocompostos/química , Paládio/química , Dióxido de Silício/química , Catálise , Nanocompostos/ultraestrutura , Porosidade
8.
ACS Appl Mater Interfaces ; 6(17): 15448-55, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25137502

RESUMO

Among the issues that restrict the power conversion efficiency (PCE) of quantum-dot-sensitized solar cells (QDSSCs), insufficient catalytic activity and stability of counter electrodes (CEs) are critical but challenging ones. The state-of-the-art Cu/Cu2S CEs still suffer from mechanical instability and uncertainty due to the reaction of copper and electrolyte. Herein, ITO@Cu2S core-shell nanowire arrays were developed to fabricate CEs for QDSSCs, which have no such issues in Cu/Cu2S CEs. These nanowire arrays exhibited small charge transfer resistance and sheet resistance, and provided more active catalytic sites and easy accessibility for electrolyte due to the three-dimensional structure upon use as CEs. More interestingly, it was found that the interface of ITO/Cu2S significantly affected the performance of ITO@Cu2S nanowire array CEs. By varying synthetic methods, a series of ITO@Cu2S nanowire arrays were prepared to investigate the influence of ITO/Cu2S interface on their performance. The results showed that ITO@Cu2S nanowire array CEs with a continuous Cu2S nanocrystal shell fabricated via an improved cation exchange route exhibited excellent and thickness-dependent performance. The PCE of corresponding QDSSCs increased by 11.6 and 16.5% compared to that with the discrete Cu2S nanocrystal and the classic Cu/Cu2S CE, respectively, indicating its promising potential as a new type of CE for QDSSCs.

9.
ACS Appl Mater Interfaces ; 6(16): 14653-9, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25073122

RESUMO

A sandwichlike magnesium silicate/reduced graphene oxide nanocomposite (MgSi/RGO) with high adsorption efficiency of organic dye and lead ion was synthesized by a hydrothermal approach. MgSi nanopetals were formed in situ on both sides of RGO sheets. The nanocomposite with good dispersion of nanopetals exhibits a high specific surface area of 450 m(2)/g and a good mass transportation property. Compared to MgSi and RGO, the mechanical stability and adsorption capacity of the nanocomposite is significantly improved due to the synergistic effect. The maximum adsorption capacities for methylene blue and lead ion are 433 and 416 mg/g, respectively.

10.
Chem Commun (Camb) ; 50(71): 10307-10, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25058657

RESUMO

C60 fullerenol was found to be a highly active, selective and stable catalyst for cycloaddition between CO2 and epoxides to produce various cyclic carbonates with excellent yields (89-99%). A solid/liquid interfacial hydrogen-bond assisted mechanism was proposed to account for its high efficiency.

11.
Nanoscale ; 6(1): 442-8, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24212438

RESUMO

A hierarchical core-shell-satellite structured composite system Fe3O4@MS-NH2@Pd, which was composed of Pd nanoparticles well-dispersed on an amino group functionalized mesoporous silica (MS-NH2) nanosphere, and superparamagnetic Fe3O4 nanoparticles scattered inside the silica sphere, was prepared by using a facile procedure. The composite combined the catalytic properties of amino groups and Pd nanoparticles with superparamagnetic properties of magnetite into a single platform. This integrated nanosystem acted as an efficient magnetically recyclable noble metal-base multifunctional nanocatalyst and showed excellent catalytic activity, selectivity and stability for the direct synthesis of α-alkylated nitriles under mild conditions through facile one-pot multistep cascade reaction sequences.

12.
Nano Lett ; 14(1): 365-72, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24350879

RESUMO

Quantum-dot-sensitized solar cell (QDSSC) has been considered as an alternative to new generation photovoltaics, but it still presents very low power conversion efficiency. Besides the continuous effort on improving photoanodes and electrolytes, the focused investigation on charge transfer at interfaces and the rational design for counter electrodes (CEs) are recently receiving much attention. Herein, core-shell nanowire arrays with tin-doped indium oxide (ITO) nanowire core and Cu2S nanocrystal shell (ITO@Cu2S) were dedicatedly designed and fabricated as new efficient CEs for QDSSCs in order to improve charge collection and transport and to avoid the intrinsic issue of copper dissolution in popular and most efficient Cu/Cu2S CEs. The high-quality tunnel junctions formed between n-type ITO nanowires and p-type Cu2S nanocrystals led to the considerable decrease in sheet resistance and charge transfer resistance and thus facilitated the electron transport during the operation of QDSSCs. The three-dimensional structure of nanowire arrays provided high surface area for more active catalytic sites and easy accessibility for an electrolyte. As a result, the power conversion efficiency of QDSSCs with the designed ITO@Cu2S CEs increased by 84.5 and 33.5% compared to that with planar Au and Cu2S CEs, respectively.

13.
Chemistry ; 19(34): 11172-7, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23839865

RESUMO

Layered structure: α-Fe2 O3 nanodisks with a layered structure assembled from nanoplates were produced by a hydrothermal method. The simple, low-cost method used silicate anions as capping ligands, which selectively adsorbed onto the {0001} facet of α-Fe2 O3 and terminated the growth along the [0001] direction, leading to platelike building units. The layered structure led to significantly enhanced absorption of visible light, compared with single-layer α-Fe2 O3 , and excellent photocatalytic abilities.

14.
Chem Asian J ; 8(10): 2459-65, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23780796

RESUMO

Two kinds of multifunctional nanocomposites, SBA-15-NH2/Pd-p and SBA-15-NH2/Pd-f, with platelet-like and fiber-like morphologies, respectively, were fabricated by immobilizing Pd NPs onto amine-functionalized SBA-15. Some of the amino groups acted as anchoring sites for Pd NPs, whilst the remaining groups acted as Brønsted basic sites. As a result, the composites served as excellent multifunctional heterogeneous catalysts for one-pot multistep cascade reaction sequences. Moreover, when diffusion was the rate-determine step, SBA-15-NH2/Pd-p, with small mesopores, was superior to the fiber-like control sample, owing to its short diffusion length, a lower possibility of pore clogging, and better mass transportation for the reaction species during the catalysis.

15.
Chem Commun (Camb) ; 49(54): 6093-5, 2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23727945

RESUMO

Flower-like MgO is a highly effective catalyst for the synthesis of dimethyl carbonate through the transesterification method, and coating the catalyst with mesoporous silica significantly enhances the stability of the MgO catalyst.


Assuntos
Formiatos/síntese química , Óxido de Magnésio/química , Dióxido de Silício/química , Catálise , Esterificação , Formiatos/química , Porosidade
16.
ACS Appl Mater Interfaces ; 5(12): 5777-82, 2013 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-23701368

RESUMO

A novel layered zinc silicate/carbon composite was fabricated through carbon embedment into the interlayers of zinc silicate through a hydrothermal method. The interlayer space could be effectively tuned from 1.22 to 3.37 nm by controlling the amount of carbon precursors. Such a layered zinc silicate/carbon structure promoted the lithium ions and electron transportation within the nanostructures, while the reduced graphene oxide (RGO) network improved the conductivity between nanostructures. Such a 3-D carbon based conductive network improved zinc silicates' lithium storage property. After 50 cycles, two composite samples with different carbon loadings showed 778 mA h/g and 704 mA h/g, respectively.

17.
ACS Appl Mater Interfaces ; 5(9): 3932-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23594186

RESUMO

A composited anode material with combined layered α-Fe2O3 nanodisks and reduced graphene oxide was produced by an in situ hydrothermal method for lithium-ion batteries. As thin as about 5-nm-thickness α-Fe2O3 nanosheets, open channels, and face-to-face tight contact with reduced graphene oxide via oxygen bridges made the composite have a good cyclability and rate performance, especially at high charge/discharge rates.

18.
Chem Commun (Camb) ; 49(30): 3116-8, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23467689

RESUMO

A new nanoreactor-type composite catalyst with Au NPs embedded into the inner wall of the mesoporous TiO2 hollow spheres resulted in an enhanced synergistic effect and superb thermal stability of highly dispersed Au NPs.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Temperatura , Titânio/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
19.
Chem Commun (Camb) ; 49(23): 2332-4, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-23403459

RESUMO

Through a simple polymeric carbon assisted method, a yolk-shell structured Fe(2)O(3)@mesoporous SiO(2) nanoreactor was synthesized and showed excellent activity in Fenton-like reactions toward methylene blue total degradation.


Assuntos
Corantes/química , Compostos Férricos/química , Peróxido de Hidrogênio/química , Ferro/química , Nanopartículas Metálicas/química , Dióxido de Silício/química , Catálise , Nanopartículas Metálicas/ultraestrutura , Azul de Metileno/química , Oxirredução , Porosidade
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