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Transition metal oxides are a potential anode material owing to their high theoretical capacity. Nonetheless, their large volume changes and low electrical conductivities lead to poor cycling performance and rate capabilities. In this article, an effective strategy is proposed and developed for preparing a ZnO/N-doped graphene composite (ZnNc/GO-5). The key point of this strategy is to use zinc tetra tert-butyl-naphthalocyanine (ZnNc) as a codoped source of N atoms and zinc ions, and graphene oxide (GO) which is combined with ZnNc by π-π deposition as a carbon matrix. After calcination, ZnO microcrystals coated with N-doped graphene are obtained. The unique features of the composite and synergistic effect between N-doped reduced graphene oxide and ZnO microcrystals enable good electrochemical performance by the composites when used in lithium-ion batteries. As an anode material, the as-synthesized ZnNc/GO-5 composite delivers a high first capacity of 1942.9 mAh g-1 and excellent cyclic stability of 861.4 mAh g-1 after 150 cycles at 100 mA g-1. This strategy may offer a new method of designing the anode materials of lithium-ion batteries and promote the practical use of organic molecules in next-generation lithium-ion batteries.
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Naphthalocyanine and its derivatives are new types of functional materials with wide application prospects. This paper discusses the synthesis of copper tetra tert-butyl-naphthalocyanine (CuNc) and analyses its molecular and electronic structure. Next, CuNc is combined with graphene oxide (GO) through π-π interaction and then pyrolyzed to form a CuNc/GO composite. A systematic investigation of the morphology, structure, composition and properties of CuNc/GO revealed that N-doped graphene is decorated with CuO particles. The electrochemical properties of CuNc/GO are compared with those of directly pyrolysed CuNc. The prepared CuNc/GO (1 : 1) electrode shows a large specific capacity (655.1 mA h g-1) after 100 cycles at 100 mA g-1. Its high capacity, enhanced cycling stability and strong rate performance are attributed to the synergetic effect of N-doped graphene and CuO particles. Besides expanding the use of naphthalocyanine compounds, this work presents a promising candidate material for lithium-ion battery anodes.
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A method for increasing the solubilities of industrial azo pigments in DMSO by adding DBU (1,8-diaza-7-bicyclo[5.4.0]undecene) has been developed. This facilitated the acquisition of solution 13 C NMR spectra of the pigments. This method was applied to four types of azo pigments: naphthol AS (3-hydroxy-2-naphthoic acid anilide) pigments, naphthol pigments, pyrazolone pigments and acetoacetanilide pigments. This represents the first solution 13 C NMR spectra for naphthol AS pigments. Altogether 18 industrial azo pigments were analysed using 1D and 2D NMR techniques. The proton and corresponding carbon NMR resonances of these pigments have all been assigned.
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Compostos Azo/química , Corantes/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Dimetil Sulfóxido/química , Espectroscopia de Prótons por Ressonância Magnética/métodos , SolubilidadeRESUMO
Background Although pain is one of the most distressing non-motor symptoms among patients with Parkinson's disease, the underlying mechanisms of pain in Parkinson's disease remain elusive. The aim of the present study was to investigate the role of serotonin (5-hydroxytryptamine) in the rostral ventromedial medulla (RVM) and spinal cord in pain sensory abnormalities in a 6-hydroxydopamine-treated rat model of Parkinson's disease. Methods The rotarod test was used to evaluate motor function. The radiant heat test and von Frey test were conducted to evaluate thermal and mechanical pain thresholds, respectively. Immunofluorescence was used to examine 5-hydroxytryptamine neurons and fibers in the rostral ventromedial medulla and spinal cord. High-performance liquid chromatography was used to determine 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels. Results The duration of running time on the rotarod test was significantly reduced in 6-hydroxydopamine-treated rats. Nociceptive thresholds of both mechanical and heat pain were reduced compared to sham-treated rats. In addition to the degeneration of cell bodies and fibers in the substantia nigra pars compacta, the number of rostral ventromedial medulla 5-hydroxytryptamine neurons and 5-hydroxytryptamine fibers in the spinal dorsal horn was dramatically decreased. 5-Hydroxytryptamine concentrations in both the rostral ventromedial medulla and spinal cord were reduced. Furthermore, the administration of citalopram significantly attenuated pain hypersensitivity. Interestingly, Intra-rostral ventromedial medulla (intra-RVM) microinjection of 5,7-dihydroxytryptamine partially reversed pain hypersensitivity of 6-hydroxydopamine-treated rats. Conclusions These results suggest that the decreased 5-hydroxytryptamine contents in the rostral ventromedial medulla and spinal dorsal horn may be involved in hyperalgesia in the 6-hydroxydopamine-induced rat model of Parkinson's disease.
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Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Bulbo/metabolismo , Doença de Parkinson/complicações , Serotonina/metabolismo , Transdução de Sinais/fisiologia , Medula Espinal/metabolismo , 5,7-Di-Hidroxitriptamina/uso terapêutico , Animais , Modelos Animais de Doenças , Indóis/metabolismo , Masculino , Bulbo/efeitos dos fármacos , Oxidopamina/toxicidade , Doença de Parkinson/etiologia , Doença de Parkinson/patologia , Ratos , Ratos Sprague-Dawley , Receptores Opioides mu/metabolismo , Serotoninérgicos/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Medula Espinal/efeitos dos fármacos , Simpatolíticos/toxicidade , Tirosina 3-Mono-Oxigenase/metabolismo , Ácido gama-Aminobutírico/metabolismoRESUMO
Two polymer catalysts (Pd-OCMCS and Ni-OCMCS) with good reusability were synthesized by coordinating Pd and Ni onto O-carboxymethyl chitosan (OCMCS). The chemical structure and thermal stability of prepared catalysts were determined by Fourier transform infrared (FT-IR) spectra, Energy Dispersive Spectrometer (EDS)analysis, X-ray diffraction (XRD), and thermogravimetric analyzer (TG-DTG), and the analysis results showed that the Pd and Ni ions coordinated onto the OCMCS and formed a ligand with the -COOH group, amino groups, and -OH group on the OCMCS, and the EDS and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) analysis results showed that the loading amounts of Pd and Ni were approximately 8.3% and 8.9%, respectively. In the Heck reaction between aryl halides and n-butyl acrylate catalyzed by the prepared catalyst, the test results showed that the product yield followed the order of aryl iodide > aryl bromide > aryl chloride. Additionally, the product yield for the aryl iodide and aryl bromide could reach up to 99% and 96%, respectively. Moreover, the electron-withdrawing and electron-donating property of the group on the aryl also affected the product yield, and the product yield for aryl halides with electron-withdrawing group p-NO2, p-CH3CO, and p-CHO was higher than that with electron-donating group p-CH3.
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Acrilatos/química , Derivados de Benzeno/química , Quitosana/análogos & derivados , Elétrons , Níquel/química , Paládio/química , Compostos de Benzil/química , Catálise , Quitosana/química , Reutilização de Equipamento , Microscopia Eletrônica de VarreduraRESUMO
Navigating more effective methods to enhance the photon utilization of photodetectors poses a significant challenge. This study initially investigates the impact of morphological alterations in 2H-MoS2 on photodetector (PD) performance. The results reveal that compared to layered MoS2 (MoS2 NLs), MoS2 nanotubes (MoS2 NTs) impart a cavity enhancement effect through multiple light reflections. This structural feature significantly enhances the photodetection performance of the MoS2-based PDs. We further employ the heterojunction strategy to construct Y-TiOPc NPs:MoS2 NTs, utilizing Y-TiOPc NPs (Y-type titanylphthalocyanine) as the vis-NIR photosensitizer and MoS2 NTs as the photon absorption enhancer. This approach not only addresses the weak absorption of MoS2 NTs in the near-infrared region but also enhances carrier generation, separation, and transport efficiency. Additionally, the band bending phenomenon induced by trapped-electrons at the interface between ITO and the photoactive layer significantly enhances the hole tunneling injection capability from the external circuit. By leveraging the synergistic effects of the aforementioned strategies, the PD based on Y-TiOPc NPs:MoS2 NTs (Y:MT-PD) exhibits superior photodetection performance in the wavelength range of 365-940 nm compared to MoS2 NLs-based PD and MoS2 NTs-based PD. Particularly noteworthy are the peak values of key metrics for Y:MT-PD, such as EQE, R, and D* that are 4947.6%, 20588 mA/W, and 1.94 × 1012 Jones, respectively. The multiperiod time-resolved photocurrent response curves of Y:MT-PD also surpass those of the other two PDs, displaying rapid, stable, and reproducible responses across all wavelengths. This study provides valuable insights for the further development of photoactive materials with a high photon utilization efficiency.
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Research on the dynamics of crystal transformation can guide production practices and improve the coloration performance of pigment Red 170. As one of the most important azo dyes, the low hiding power, inferior weather resistance, thermal instability, and low flowability of pigment Red 170 limit its applications. To enhance these properties, it is essential to modify the surface of the pigment. Herein, the crystal transformation and isothermal crystallisation kinetics of colour index (C.I.) pigment Red 170 during a hydrothermal process were studied through X-ray powder diffraction. During isothermal crystallisation, the Avrami indexes (n) were 2.65 and 3.01, and the kinetic rate constants (K) were 6.02 × 10-6 and 8.34 × 10-6 at 140 and 150 °C, respectively. The apparent activation energies (E) are 10.42 and 24.31 kcal mol-1 for the incubation period and total transition, respectively. Pigment Red 170 completely transferred from an α-phase to γ-phase upon hydrothermal treatment at 140 and 150 °C for 180 and 90 min, respectively. The effects of heat treatment temperature and time on the colour hue, tinctorial strength, flowability, particle size and distribution, contact angle, thermal stability, and morphology of pigment Red 170 were investigated. In addition, kaolin was used as an inorganic additive to modify γ-phase pigment Red 170. After hydrothermal treatment and kaolin modification, C.I. pigment Red 170 had a small particle size and exhibited a narrow size distribution and improved hydrophilicity. The γ-phase pigments had a tinctorial strength of 189.5%. The flowability and thermal stability of the kaolin-modified pigment were also enhanced. This study promotes the development of pigments with enhanced colour properties, thermal stability, and processability.
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Organic pigments are important in a range of fields, from printing ink to industrial coatings. Azo pigments are some of the most common pigments in use today, but they typically have poor solvent solubility and tend to agglomerate. Consequently, the size and crystal structure of the pigment particles has a crucial effect on their optical and physical properties, such as color strength and solvent resistance, respectively. Several technologies, such as microreactors, have been developed to control pigment particle size, but an in-depth study of the effects of modification conditions on pigment properties (color, flowability, and solvent resistance) has not been reported to date. Therefore, in this paper, we report the surface modification of C.I. Pigment Red 146 particles using anionic (Igepon T) and non-ionic surfactants (Peregal O-25) and additives (DB-60 as the second diazo component and graphene oxide) on the pigment properties. In addition, we examined the effect of hydrothermal treatment at different temperatures on the same properties. The various modifications resulted in an increase in the solvent resistance, a reduction in the particle size (from 30.581 to 12.252 µm), a narrowing of the particle size distribution, and an increase in hydrophilicity. In addition, the color brightness and brilliance were significantly improved, and the maximum color strength reached 112.6%. These findings have applications for the development of pigments having enhanced color properties, solvent resistance, and processability.
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Design and preparation of gels with excellent mechanical properties has garnered wide interest at present. In this paper, preparation of polyvinyl alcohol (PVA)-tannic acid (TA) gels with exceptional properties is documented. The crystallization zone and hydrogen bonding acted as physical crosslinkages fabricated by a combination of freeze-thaw treatment and a tannic acid compound. The effect of tannic acid on mechanical properties of prepared PVA-TA gels was investigated and analyzed. When the mass fraction of PVA was 20.0 wt% and soaking time was 12 h in tannic acid aqueous solution, tensile strength and the elongation at break of PVA-TA gel reached 5.97 MPa and 1450%, respectively. This PVA-TA gel was far superior to a pure 20.0 wt% PVA hydrogel treated only with the freeze-thaw process, as well as most previously reported PVA-TA gels. The toughness of a PVA-TA gel is about 14 times that of a pure PVA gel. In addition, transparent PVA-TA gels can effectively prevent ultraviolet-light-induced degradation. This study provides a novel strategy and reference for design and preparation of high-performance gels that are promising for practical application.
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In this work, the effect of confined space on crystallization processes of pigments was investigated by using C.I. Pigment Red 146 (PR 146) as a model compound. The colloidal system (i.e., emulsion droplets) was used as a nanoreactor to prepare nanoscale PR 146 for the inkjet printer. The effects of the space confinement were investigated by comparing the products of PR 146 prepared from bulk solution, macroemulsion, and miniemulsion. The results showed that PR 146 crystallized in mini-emulsion had the narrowest particle size distribution and the average particle size can be as small as 172.5 nm, one order of magnitude smaller than the one obtained from the bulk solution. X-ray diffraction (XRD) data revealed that PR 146 crystallized in all three solutions where the crystalline state and had similar crystallite sizes. The process mechanism of crystallization confined in the miniemulsion droplets was proposed and explained. The function mechanism of the co-stabilizer during the crystallization of PR 146 in emulsion was also explained. It was found that sodium chloride could counteract the pressure difference as an osmotic pressure agent and prevent the migrating of water from small droplets into big droplets. The influences of dosages of emulsifiers and co-stabilizers on droplet size and the size of the obtained PR 146 particles were evaluated and the optimal conditions were determined. Furthermore, the disparity of PR 146 products prepared by different methods was investigated by UVâ»Vis spectra. The aqueous dispersion of PR 146 crystallized in miniemulsion had the highest absorbance and darkest color.
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Olfactory impairment is an early feature of patients with Parkinson's disease (PD). Retrospective epidemiological studies reported lower scores on the University of Pennsylvania Smell Identification Test (UPSIT) in non-smokers than smokers with PD and showed an inverse correlation between susceptibility to PD and a person's history of smoking. But the mechanisms by which cigarettes affect olfaction in PD are not fully understood. So we investigated the effect of nicotine on the olfactory function in 1-methyl-4-phenyl-1, 2, 3, 6 tetrahydropyridine (MPTP)-treated mice. We observed that nicotine improved locomotor activity and protection against dopaminergic neuron loss in the midbrain in MPTP-treated mice. Compared to controls, MPTP-treated mice showed a deficit of odor discrimination and odor detection, which were alleviated by nicotine treatment. But no significant changes were found in olfactory memory in MPTP-treated mice. Moreover, we detected a marked decrease of Choline acetyltransferase (ChAT) expression in the olfactory bulb (OB) in MPTP-treated mice, which was also attenuated by nicotine administration. In addition, nicotine ameliorated the loss of cholinergic neurons and dopaminergic innervation in the horizontal limb of the diagonal band (HDB), which is the primary origin of cholinergic input to the OB. Our results suggested that nicotine could improve the olfactory impairment by protecting cholinergic systems in the OB of MPTP-treated mice. And nicotine protection of cholinergic systems in the OB is relevant to attenuating dopaminergic neuron loss in the midbrain and HDB.
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Antiparkinsonianos/farmacologia , Comportamento Animal/efeitos dos fármacos , Intoxicação por MPTP/tratamento farmacológico , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Bulbo Olfatório/efeitos dos fármacos , Percepção Olfatória/efeitos dos fármacos , Olfato/efeitos dos fármacos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Locomoção/efeitos dos fármacos , Intoxicação por MPTP/induzido quimicamente , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Bulbo Olfatório/metabolismo , Bulbo Olfatório/patologia , Bulbo Olfatório/fisiopatologia , Transdução de Sinais , Tirosina 3-Mono-Oxigenase/metabolismoRESUMO
Parkinson's disease (PD) is the second most common neurodegenerative disorder in the world. Apart from motor deficits, PD reduces patient's quality of life through sleep disturbances, cognitive impairment and emotional disorders. However, it's unclear whether bad life habits such as stay up late exacerbate the patient's cognition and emotional disorders. Thus we investigated the consequences of sleep deprivation (SD) on memory and emotions using a rotenone-based zebrafish model of PD. Behavioral assays, using locomotor activity assay, showed that rotenone treated zebrafish exhibited PD-like symptoms, whereas sleep deprivation didn't exacerbate the progression of them. The object discrimination task exhibited that the short-term cognitive deficits of rotenone group are more serious than the sham group after SD. Light-dark box test showed that rotenone treated fish are more dysphoric than the sham fish after SD. Dopamine and DOPAC significantly reduced in rotenone treated fish compared with the sham fish. However, this DOPAC reduction recovered after SD. The expression of D2 and D3 in rotenone treated zebrafish elevated compared with sham group and SD group. However, the rotenone treated zebrafish manifested a decrease level of D2 and D3 after SD. D1 did not show any significantly changes among the four groups. Our findings suggest that zebrafish treated with rotenone may have a more severe damage of memory and emotional function after SD, which may be related to the changes in the DA systems.
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Emoções/fisiologia , Memória/fisiologia , Privação do Sono/fisiopatologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Cognição/fisiologia , Modelos Animais de Doenças , Dopamina/metabolismo , Masculino , Atividade Motora , Doença de Parkinson/fisiopatologia , Rotenona/farmacologia , Privação do Sono/metabolismo , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologiaRESUMO
Parkinson's disease (PD) is the second most common neurodegenerative disease and is known to involve circadian dysfunction and oxidative stress. Although antioxidative defense is regulated by the molecular circadian clock, few studies have examined their function in PD and their regulation by silent information regulator 1 (SIRT1). We hypothesize that reduced antioxidative activity in models of PD results from dysfunction of the molecular circadian clock via the SIRT1 pathway. We treated rats and SH-SY5Y cells with 6-hydroxydopamine (6-OHDA) and measured the expression of core circadian clock and associated nuclear receptor genes using real-time quantitative PCR as well as levels of SIRT1, brain and muscle Arnt-like protein 1 (BMAL1), and acetylated BMAL1 using Western blotting. We found that 6-OHDA treatment altered the expression patterns of clock and antioxidative molecules in vivo and in vitro. We also detected an increased ratio of acetylated BMAL1:BMAL1 and a decreased level of SIRT1. Furthermore, resveratrol, an activator of SIRT1, decreased the acetylation of BMAL1 and inhibited its binding with CRY1, thereby reversing the impaired antioxidative activity induced by 6-OHDA. These results suggest that a dysfunctional circadian clock contributes to an abnormal antioxidative response in PD via a SIRT1-dependent BMAL1 pathway.
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Fatores de Transcrição ARNTL/metabolismo , Antioxidantes/metabolismo , Relógios Circadianos/fisiologia , Doença de Parkinson Secundária/metabolismo , Sirtuína 1/metabolismo , Animais , Relógios Circadianos/efeitos dos fármacos , Masculino , Oxidopamina , Ratos , Ratos Sprague-DawleyRESUMO
A new preparation method of polymer dyes was developed to improve both the grafting degree of the azo dyes onto O-carboxymethyl chitosan (OMCS) and the water solubility of prepared polymer dyes. Firstly, the coupling compound of two azo edible colorants, sunset yellow (SY) and allura red (AR), was grafted onto OMCS, and then coupled with their diazonium salt. The chemical structure of prepared polymer dyes was determined by Fourier transform-infrared spectroscopy and ¹H-NMR, and the results showed that the two azo dyes were successfully grafted onto OMCS. The grafting degree onto OMCS and the water solubility of polymer dyes were tested, and the results showed that they were both improved as expected. The UV-vis spectra analysis results showed that the prepared polymer dyes showed similar color performance with the original azo dyes. Eventually, the cytotoxicity of prepared polymer dyes was tested and compared with the original azo dyes by a cytotoxicity test on human liver cell lines LO2, and the results showed that their grafting onto OMCS significantly reduced the cytotoxicity.
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Many studies reveal that BAG3 plays a critical role in the regulation of protein degradation via macroautophagy. However, it remains unknown whether BAG3 affects the quality control of α-synuclein (SNCA), a Parkinson's disease-related protein. In this study, we demonstrated the increases of BAG3 expression in the ventral midbrain of SNCAA53T transgenic mice and also in MG132-treated PC12 cells overexpressing wild-type SNCA (SNCAWT-PC12). Moreover, we showed that BAG3 overexpression was sufficient to enhance the autophagy activity while knockdown of Bag3 reduced it in SNCAWT-PC12 cells. Immunoprecipitation revealed that BAG3 interacted with heat shock protein 70 and sequestosome 1. The immunostaining also showed the perinuclear accumulation and colocalization of BAG3 with these 2 proteins, as well as with LC3 dots in tyrosine hydroxylase-positive neurons in the midbrain of SNCAA53T mice. BAG3 overexpression was able to modulate SNCA degradation via macroautophagy which was prevented by Atg5 knockdown. Taken together, these results indicate that BAG3 plays a relevant role in regulating SNCA clearance via macroautophagy, and the heat shock protein 70-BAG3-sequestosome 1 complex may be involved in this process.