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1.
Pharmaceuticals (Basel) ; 16(10)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37895936

RESUMO

Oxaliplatin is a chemotherapy drug that can induce severe acute neuropathy in patients within hours of treatment. In our previous study, 10 mg/kg [6]-shogaol (i.p.) significantly alleviated cold and mechanical allodynia induced by a 6 mg/kg oxaliplatin injection (i.p.); however, the precise serotonin-modulatory effect has not been investigated. In this study, we showed that intrathecal injections of NAN-190 (5-HT1A receptor antagonist, 1 µg) and MDL-72222 (5-HT3 receptor antagonist, 15 µg), but not ketanserin (5-HT2A receptor antagonist, 1 µg), significantly blocked the analgesic effect of [6]-shogaol (10 mg/kg, i.p.). Furthermore, the gene expression of the serotonin-synthesizing enzyme tryptophan hydroxylase 2 (TPH2) and serotonin levels in the spinal cord and serum were significantly downregulated (p < 0.0001 and p = 0.0002) and upregulated (p = 0.0298 and p = 0.0099) after oxaliplatin and [6]-shogaol administration, respectively. Moreover, both the gene and protein expression of the spinal serotonin receptors 5-HT1A and 5-HT3 significantly increased after [6]-shogaol injections (p < 0.0001). Finally, intrathecal injections of both receptor agonists (8-OH-DPAT; 5-HT1A receptor agonist, 10 µg and m-CPBG; 5-HT3 receptor agonist, 15 µg) mimicked the effects of [6]-shogaol in oxaliplatin-injected mice. Taken together, these results demonstrate that [6]-shogaol attenuates oxaliplatin-induced neuropathic pain by modulating the spinal serotoninergic system.

2.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35745645

RESUMO

Although oxaliplatin is a well-known anti-cancer agent used for the treatment of colorectal cancer, treated patients often experience acute cold and mechanical allodynia as side effects. Unfortunately, no optimal treatment has been developed yet. In this study, [6]-shogaol (10 mg/kg, i.p.), which is one of the major bioactive components of Zingiber officinale roscoe (Z. officinale), significantly alleviated allodynia induced by oxaliplatin (6 mg/kg, i.p.) injection. Cold and mechanical allodynia were assessed by acetone drop and von Frey filament tests, respectively. The analgesic effect of [6]-shogaol was blocked by the intrathecal injection of 5-HT1A, 5-HT3, and GABAB receptor antagonists, NAN-190 (1 µg), MDL-72222 (15 µg), and CGP 55845 (10 µg), respectively. Furthermore, oxaliplatin injection lowered the GABA concentration in the superficial laminae of the spinal dorsal horn, whereas [6]-shogaol injection significantly elevated it. The GAD (glutamic acid decarboxylase) 65 concentration also increased after [6]-shogaol administration. However, pre-treatment of NAN-190 completely inhibited the increased GABA induced by [6]-shogaol in the spinal dorsal horn, whereas MDL-72222 partially blocked the effect. Altogether, these results suggest that [6]-shogaol could attenuate oxaliplatin-induced cold and mechanical allodynia through 5-HT1A and 5-HT3 receptor antagonists located in the GABAergic neurons in the spinal dorsal horn in mice.

3.
Environ Technol ; : 1-11, 2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34057402

RESUMO

Polymers are highly promising materials for capturing carbon dioxide (CO2), a greenhouse gas. Hence in this work, we prepared phyllosilicate supported mesoporous polymer via reversible addition-fragmentation chain transfer (RAFT) polymerisation, which is the one among the controlled radical polymerisation. The mesoporous material anchored on dodecanethiol trithiocarbonate acts as a chain transfer agent (CTA) for the polymerisation of chloromethyl styrene and further conversion to quaternary ammonium compound which is effective to trap CO2 using tertiary amine. The synthesised porous phyllosilicate/polymer nanocomposites have been characterised by using various analytical tools. The CO2 sorption experiments were carried out by passing CO2 onto the synthesised porous phyllosilicate/polymer nanocomposites. The sorption kinetics was monitored by X-Ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) spectra in the presence of carbonate were obtained by reaction of quaternary ammonium hydroxide and CO2. The phyllosilicate anchored macromolecular CTA (macro-CTA) and the surface-initiated polymer nanocomposites encompassed apparent surface areas of 94.5 and 26.8 m2 g-1, respectively. In addition, the total pore volumes calculated for the macro-CTA and polymer were found to be 0.27 and 0.095 cm3g-1, while the average pore sizes were 14.24 and 11.46 nm, respectively. The CO2 sorption capacity of the phyllosilicate/polymer nanocomposites, monitored at different temperatures, is the fastest for 25°C but slower for the sample treated at 50°C which may due to the dipole and quadrupole interaction.

4.
Toxins (Basel) ; 12(12)2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255279

RESUMO

Oxaliplatin is a third-generation platinum-based chemotherapeutic drug widely used in colorectal cancer treatment. Although potent against this tumor, it can induce cold and mechanical allodynia even after a single injection. The currently used drugs to attenuate this allodynia can also cause unwanted effects, which limit their use. Bee venom acupuncture (BVA) is widely used in Korean medicine to treat pain. Although the effect of BVA on oxaliplatin-induced neuropathic pain has been addressed in many studies, its action on dorsal root ganglia (DRG) neurons has never been investigated. A single oxaliplatin injection (6 mg/kg, intraperitoneally) induced cold and mechanical allodynia, and BVA (0.1 and 1 mg/kg, subcutaneous, ST36) dose-dependently decreased allodynia in rats. On acutely dissociated lumbar 4-6 DRG neurons, 10 min application of oxaliplatin (100 µM) shifted the voltage-dependence of sodium conductance toward negative membrane potentials in A- but not C-fibers. The resting membrane potential remained unchanged, but the action potential threshold decreased significantly compared to that of the control (p < 0.05). However, 0.1 µg/mL of BVA administration increased the lowered action potential threshold. In conclusion, these results suggest that BVA may attenuate oxaliplatin-induced neuropathic pain by altering the action potential threshold in A-fiber DRG neurons.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Terapia por Acupuntura , Venenos de Abelha/farmacologia , Gânglios Espinais/efeitos dos fármacos , Neuralgia/tratamento farmacológico , Neurônios/efeitos dos fármacos , Oxaliplatina/efeitos adversos , Animais , Antineoplásicos/uso terapêutico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Neuralgia/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Canais de Sódio Disparados por Voltagem/metabolismo
5.
ACS Omega ; 5(13): 7201-7210, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32280860

RESUMO

In this work, hydrophilic polymers modified with iron oxide nanoparticles, such as iron oxide-poly(2-dimethylaminoethyl methacrylate) [P(DMAEMA)] magnetite-based and iron oxide-poly(acrylamide) [P(AAm)] magnetite-based polymers, were prepared via a single electron transfer-living radical polymerization approach. Bile acid and 2-bromo-2-methylpropionic acid were covalently attached onto the surface of Fe3O4 nanoparticles, and these immobilized magnetite nanoparticles were used as an initiator for the polymerization. The binding capabilities of different ions, such as Hg2+, CN-, Cl-, F-, and NO3 -, were tested using these polymeric sensors monitored by UV-vis spectroscopy. Magnetite-based P(DMAEMA) showed enhanced binding capability due to the presence of tertiary amine groups. In addition, it was possible to easily separate the bound ions from aqueous media using an external magnetic field.

6.
Nanomaterials (Basel) ; 10(3)2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32164266

RESUMO

Copper-doped bismuth vanadate/graphitic carbon nitride (BiVO4/g-C3N4) nanocomposite materials were successfully fabricated using a sonochemical approach. Cu-doped BiVO4/g-C3N4 nanocomposite photocatalysts could improve electron/hole (e-/h+) pair separation, stability, and light-harvesting efficiency compared to pristine BiVO4 or g-C3N4, resulting in the enhancement of photocatalytic activity. The optimal parameters, such as pH value at 10, photocatalyst dosage of 0.4 g L-1, and 10 mol% Cu-doped BiVO4/g-C3N4 photocatalyst, were determined to degrade initial concentration of 20 ppm Bisphenol A, which could be completely removed after 90 min. Furthermore, the excessive doping of copper (> 10 mol%) could not synthesize the pure monoclinic scheelite phase, which substantially resulted in the reduction of the photocatalytic activity.

7.
Nanomaterials (Basel) ; 10(3)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155885

RESUMO

Tremendous efforts have been made on the development of unique electrochemical capacitors or pseudocapacitors due to the overgrowing electrical energy demand. Here, the authors report a new and simple strategy for fabricating hybrid MnOx-coated ZnO nanorod arrays. First, the vertically aligned ZnO nanorods were prepared by chemical bath deposition (CBD) as a template providing a large surface area for active material deposition. The manganese oxide was subsequently coated onto the surface of the ZnO nanorods to form a hybrid MnOx-coated ZnO nanostructure by anodic deposition in a manganese acetate (MnA)-containing aqueous solution. The hybrid structure of MnOx-coated ZnO nanorod arrays exhibits a large surface area and high conductivity, essential for enhancing the faradaic processes across the interface and improving redox reactions at active MnOx sites. A certain concentration of the deposition solution was selected for the MnOx coating, which was studied as a function of deposition time. Cyclic voltammetry (CV) curves showed that the specific capacitance (SC) of the MnOx-coated ZnO nanostructure was 222 F/g for the deposition times at 10 s when the concentration of MnA solution was 0.25 M. The unique hybrid nanostructures also exhibit excellent cycling stability with >97.5% capacitance retention after 1200 CV cycles. The proposed simple and cost-effective method of fabricating hybrid nanostructures may pave the way for mass production of future intelligent and efficient electrochemical energy storage devices.

8.
Polymers (Basel) ; 11(1)2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30960168

RESUMO

A polyaniline (PANI)/tin oxide (SnO2) composite for a CO sensor was fabricated using a composite film composed of SnO2 nanoparticles and PANI deposition in the present study. Tin oxide nanoparticles were synthesized by the sol-gel method. The SnO2 nanoparticles provided a high surface area to significantly enhance the response to the change in CO concentration at low operating temperature (<75 °C). The excellent sensor response was mainly attributed to the relatively good properties of PANI in the redox reaction during sensing, which produced a great resistance difference between the air and CO gas at low operating temperature. Therefore, the combination of n-type SnO2 nanoparticles with a high surface area and a thick film of conductive PANI is an effective strategy to design a high-performance CO gas sensor.

9.
J Nanosci Nanotechnol ; 15(9): 6900-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26716262

RESUMO

This review article comprehensively discusses the recent development of various environmental applications of Zinc Oxide (ZnO) semiconductor materials. The synthesis of various nano/micro structured ZnO using different methods and the influence of various preparation conditions on ZnO morphology are discussed. The environmental applications of nano/micro structured zinc oxide as an adsorbent, photocatalyst, and catalyst in catalytic ozonation processes are discussed. The adsorption of various organic pollutants and metal ions on the ZnO surface at different conditions are discussed. The ZnO assisted photocatalytic degradation of pollutants, water splitting, and disinfection under various conditions are reported on. Ozonation in the presence of zinc oxide and its influence on the removal of pollutants are also included.

10.
Langmuir ; 31(9): 2790-9, 2015 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-25652230

RESUMO

MnO2 typically coexists with iron oxides as either discrete particles or coatings in soils and sediments. This work examines the effect of Aldrich humic acid (AHA), alginate, and pyromellitic acid (PA) as representative natural organic matter (NOM) analogues on the oxidative reactivity of MnO2, as quantified by pseudo-first-order rate constants of triclosan oxidation, in mixtures with goethite or hematite. Adsorption studies showed that there was low adsorption of the NOMs by MnO2, but high (AHA and alginate) to low (PA) adsorption by the iron oxides. Based on the ATR-FTIR spectra obtained for the adsorbed PA on goethite or goethite + MnO2, the adsorption of PA occurred mainly through formation of outer-sphere complexes. The Fe oxides by themselves inhibited MnO2 reactivity through intensive heteroaggregation between the positively charged Fe oxides and the negatively charged MnO2; the low solubility of the iron oxides limited surface complexation of soluble Fe(3+) with MnO2. In ternary mixtures of MnO2, Fe oxides, and NOM analogues, the reactivity of MnO2 varied from inhibited to promoted as compared with that in the respective MnO2 + NOM binary mixtures. The dominant interaction mechanisms include an enhanced extent of homoaggregation within the Fe oxides due to formation of oppositely charged patches within the Fe oxides but an inhibited extent of heteroaggregation between the Fe oxide and MnO2 at [AHA] < 2-4 mg-C/L or [alginate/PA] < 5-10 mg/L, and an inhibited extent of heteroaggregation due to the largely negatively charged surfaces for all oxides at [AHA] > 4 mg-C/L or [alginate/PA] > 10 mg/L.

11.
J Nanosci Nanotechnol ; 13(10): 6635-43, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24245124

RESUMO

Biporous microsphere, flower and concaved cuboctahedrans like alpha-Fe2O3 superstructures have been synthesized by using a new synthetic method. Hydrothermal reaction of ferric chloride with potassium thiocyanate at 200 degrees C yields self-assembled microsphere, flower, and concaved cuboctahedrans like intermediates in ethanol, water:ethanol (1:1) mixed solvent and in water, respectively. These intermediates were further converted into corresponding alpha-Fe2O3 in a thermal decomposition process at 600 degrees C under oxygen atmospheric conditions. The influence of solvent, hydrothermal temperature, and concentration of iron precursors on the intermediate morphology was studied, and the growth mechanism has also been proposed. The synthesized intermediates and alpha-Fe2O3 were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM) and nitrogen adsorption analysis. The FE-SEM results indicated formation of biporous flowerlike morphology. The electrochemical properties of the flowerlike alpha-Fe2O3 electrodes in a Li-ion battery have been investigated. Plausible formation mechanisms of these intermediates were proposed.

12.
J Nanosci Nanotechnol ; 13(3): 1639-48, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23755569

RESUMO

This article reports a novel fabrication method for In(OH)3 from indium oxalate by hydrothermal process. Hydrothermal decomposition of indium oxalate at 180 degrees C for 10 h results in In(OH)3. The influence of hydrothermal experimental conditions such as temperature, time on the formation of indium hydroxide was investigated. The self-assembly process was strongly influenced the experimental conditions. The thermal decomposition of In(OH)3 at 400 degrees C results In2O3. The synthesized In(OH)3 and In2O3 were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), thermal analysis (TGA and DTA), diffuse reflectance spectra (DRS), and nitrogen adsorption analysis. The XRD patterns indicated the formation of well crystallized cubic phase In(OH)3 and In2O3. The FE-SEM results indicated formation of In(OH)3 and porous In2O3 nano/micro-cubes. The photocatalytic activity of the synthesized In(OH)3 was studied under UV light irradiation and results showed that the In(OH)3 photocatalyst was efficient for dye degradation. We proposed a plausible mechanism for the formation of In(OH)3, and In2O3 self-assembly.

13.
Ultrason Sonochem ; 19(3): 682-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21940191

RESUMO

This paper describes a highly efficient and rapid approach of synthesizing different CuO nanostructures in aqueous solutions using ultrasound irradiation of copper(II) acetate with urea/sodium hydroxide in the presence of polyvinylpyrrolidone (PVP), as stabilizing polymer. Field emission scanning electron microscope images clearly indicate the formation of CuO quasi-spherical microarchitectures and long-straw like structure in the presence of urea and sodium hydroxide. Other characterization techniques such as TEM, XRD and XPS are also provided to support the formation of such structures. One of the reasons for the formation of such CuO nanostructures may be due to the formation of a polymer-metal complex with the stabilizing polymer (PVP).


Assuntos
Cobre/química , Cobre/efeitos da radiação , Nanoestruturas/química , Nanoestruturas/efeitos da radiação , Nanoestruturas/ultraestrutura , Sonicação/métodos , Ondas de Choque de Alta Energia , Tamanho da Partícula , Doses de Radiação
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