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1.
Chem Soc Rev ; 45(20): 5717-5770, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27441314

RESUMO

Development of high performance electrode materials for energy storage is one of the most important issues for our future society. However, a lack of clear analytical views limits critical understanding of electrode materials. This review covers useful analytical work using X-ray diffraction, X-ray absorption spectroscopy, microscopy and neutron diffraction for ion storage systems. The in situ observation facilitates comprehending real-time ion storage behaviour while the ion storage system is operating, which help us to understand detailed physical and chemical properties. We will discuss how the tools have been used to reveal detailed reaction mechanisms and underlying properties of electrode materials.

2.
Drug Deliv Transl Res ; 14(3): 802-811, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38082031

RESUMO

The aim of this study was to design a tulobuterol (TUL) patch with good penetration behavior and mechanical properties. Particular attention was paid to the effect of transdermal permeation enhancers on the release process of metal ligand-based acrylic pressure-sensitive adhesive (AA-NAT/Fe3+). The type and dosage of the enhancers were screened by in vitro transdermal penetration in rat skin. The optimized formulation was evaluated in a pharmacokinetic study in rats. Furthermore, the molecular mechanism by which Azone (AZ) improves the release rate of TUL from AA-NAT/Fe3+ was investigated by FT-IR, shear strength test, rheological study, and molecular simulation. As a result, the optimized formula using AA-NAT/Fe3+ showed better mechanical properties compared to commercial products. Meanwhile, the AUC0-t and Cmax of the optimized patch were 1045 ± 89 ng/mL·h and 106.8 ± 28.5 ng/mL, respectively, which were not significantly different from those of the commercial product. In addition, AZ increased the mobility of the pressure-sensitive adhesive (PSA) rather than decreasing the drug-PSA interaction, which was the main factor in enhancing TUL release from the patch. In conclusion, a TUL transdermal drug delivery patch was successfully developed using metal-coordinated PSA, and a reference was provided for the design of metal-coordinated acrylic PSA for transdermal patch delivery applications.


Assuntos
Adesivos , Absorção Cutânea , Terbutalina/análogos & derivados , Ratos , Animais , Espectroscopia de Infravermelho com Transformada de Fourier , Ligantes , Administração Cutânea , Pele/metabolismo , Adesivo Transdérmico
3.
Eur J Pharm Biopharm ; 185: 28-43, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36828239

RESUMO

Psoriasis is an autoimmune disorder disease with abnormally activated T lymphocytes and thickening of the epidermis. The mechanism of the action of tacrolimus and paclitaxel are matched with the two only known pathogenesis of psoriasis. However, there has been no report on tacrolimus combined with paclitaxel in the treatment of psoriasis until now. The O/O ointment was prepared for the topical application to overcome poor solubility, poor skin penetration, and erratic absorption of the two drugs. A high-speed shearing method was adopted to prepare the ointment, in which propylene carbonate was used to solve tacrolimus and paclitaxel completely. The ointment showed excellent stability, slow release of the drugs, better retention in psoriatic skin, and good skin tolerance. The therapeutic efficacy of ointment was evaluated with imiquimod induced psoriatic model, and the level of expression of psoriatic biochemical markers was evaluated using the PASI score and immunohistochemistry. The cumulative PASI score was 10.8 for the imiquimod induced group, 7.8 for the tacrolimus ointment group, 8.3 for the paclitaxel ointment and 5.3 for the tacrolimus-paclitaxel (1:1) ointment group, respectively. Ointment group with tacrolimus and paclitaxel indicated a significant improvement in the phenotypic features of the psoriatic skin treated. Compared with the imiquimod group, tacrolimus-paclitaxel (1:1) ointment group was significantly reduced the level of IL-17. The results confirm that tacrolimus and paclitaxel co-loaded ointment can be an effective strategy for the treatment of psoriasis.


Assuntos
Psoríase , Surfactantes Pulmonares , Humanos , Tacrolimo , Tensoativos , Imiquimode , Pomadas , Paclitaxel , Psoríase/tratamento farmacológico , Psoríase/induzido quimicamente
4.
Nanotechnology ; 23(50): 505401, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23186940

RESUMO

Controlling the bulk and surface structure of metal oxide nanostructures is crucial to obtain superior electronic and electrochemical properties. However, the synthetic or post-treatment techniques for preparing such structures, especially those with complex configurations, still remains a challenge. Herein, we report a completely novel approach-an amorphous carbon coating on the surface coupled with a controlled metal oxidation state in the bulk-via a simple glucose treatment. The bulk and surface structures of iron oxides are controlled by the carbothermal reaction associated with the decomposition of glucose. These novel configurations of iron oxides possess an amorphous carbon layer and ferrous state with high electronic conductivity, which definitely enhances their electrochemical properties compared to pristine iron oxides. Our findings provide an effective solution for the synthesis of complex metal oxide nanostructures, which can pave the way to further expand the electronic or electrochemical applications of metal oxides.

5.
Epilepsy Res ; 154: 97-106, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31121474

RESUMO

AIMS: Glia-mediated neuro-inflammation and oxidative stress-induced neuronal apoptosis can contribute to epileptogenesis. We have demonstrated previously that mimetics of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and dual-GLP-1/GIP receptor agonists protect the brain from inflammation, oxidative stress, apoptosis and neuronal loss in animal models of central nervous system diseases. METHODS: This study investigated for the first time whether the novel dual GLP-1/GIP receptor agonist DA3-CH has neuroprotective effects in the pilocarpine-induced status epilepticus (SE) rat model and the studies the underlying mechanisms. DA3-CH was administered once daily at 10 nmol/kg ip. following SE induction. The effect of DA3-CH was evaluated by immunohistochemistry and western blot at 12 h, 1 d, 3 d, 7 d after kindling. RESULTS: Our findings show that DA3-CH reduced the chronic inflammation response (astrogliosis and microgliosis), and the associated release of the pro-inflammatory cytokines interleukin-1ß (IL-ß) and tumor necrosis factor-α (TNF-α) in the hippocampal CA1 area. Furthermore, DA3-CH reduced the expression of the mitochondrial pro-apoptotic protein Bax, while increasing the expression of the anti-apoptotic protein Bcl-2. Neuronal numbers in the CA1 area were much reduced by pilocarpine treatment, and DA3-CH protected neurons from neurotoxicity. CONCLUSION: These results demonstrated that DA3-CH could mitigate pilocarpine-induced neuro-inflammation, mitochondrial apoptosis and neuronal loss. The findings encourage the development of dual agonists as novel therapeutic interventions for epilepsy.


Assuntos
Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Fármacos Neuroprotetores/uso terapêutico , Pilocarpina/toxicidade , Receptores dos Hormônios Gastrointestinais/agonistas , Animais , Modelos Animais de Doenças , Epilepsia/fisiopatologia , Receptor do Peptídeo Semelhante ao Glucagon 1/fisiologia , Masculino , Fármacos Neuroprotetores/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores dos Hormônios Gastrointestinais/fisiologia
6.
Nat Commun ; 10(1): 3385, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477690

RESUMO

Irreversible phase transformation of layered structure into spinel structure is considered detrimental for most of the layered structure cathode materials. Here we report that this presumably irreversible phase transformation can be rendered to be reversible in sodium birnessite (NaxMnO2·yH2O) as a basic structural unit. This layered structure contains crystal water, which facilitates the formation of a metastable spinel-like phase and the unusual reversal back to layered structure. The mechanism of this phase reversibility was elucidated by combined soft and hard X-ray absorption spectroscopy with X-ray diffraction, corroborated by first-principle calculations and kinetics investigation. These results show that the reversibility, modulated by the crystal water content between the layered and spinel-like phases during the electrochemical reaction, could activate new cation sites, enhance ion diffusion kinetics and improve its structural stability. This work thus provides in-depth insights into the intercalating materials capable of reversible framework changes, thereby setting the precedent for alternative approaches to the development of cathode materials for next-generation rechargeable batteries.

7.
ACS Appl Mater Interfaces ; 7(50): 27934-9, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26619966

RESUMO

Li4Ti5O12 is a promising anode material for rechargeable lithium batteries due to its well-known zero strain and superb kinetic properties. However, Li4Ti5O12 shows low energy density above 1 V vs Li(+)/Li. In order to improve the energy density of Li4Ti5O12, its low-voltage intercalation behavior beyond Li7Ti5O12 has been demonstrated. In this approach, the extended voltage window is accompanied by the decomposition of liquid electrolyte below 1 V, which would lead to an excessive formation of solid electrolyte interphase (SEI) films. We demonstrate an effective method to improve electrochemical performance of Li4Ti5O12 in a wide working voltage range by coating Li4Ti5O12 powder with p-type semiconductor NiOx. Ex situ XRD, XPS, and FTIR results show that the NiOx coating suppresses electrochemical reduction reactions of the organic SEI components to Li2CO3, thereby promoting reversibility of the charge/discharge process. The NiOx coating layer offers a stable SEI film for enhanced rate capability and cyclability.

8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 24(3): 298-301, 2002 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12905639

RESUMO

OBJECTIVE: To investigate the availability of serum level of macrophage clony stimulating factor (M-CSF) as a marker for early diagnosis of Alzheimer's disease (AD). METHODS: The serum levels of M-CSF in 70 patients with AD, 52 healthy controls, 22 patients with VAD (vascular dementia) were measured and the serum levels of IL-1 beta, IL-6, TNF-alpha in 32 patients with AD and 20 controls were measured as well. RESULTS: Serum levels of M-CSF were significantly elevated in patients with AD when compared with healthy controls (P < 0.01) and VAD controls (P < 0.05) respectively. At the early stage of mild dementia and middle dementia, serum levels of M-CSF were significantly elevated, but at the later stage of severe dementia, they returned to normal level. Serum levels of IL-1 beta were significantly elevated in AD patients compared with controls (P < 0.05), and serum levels of TNF-alpha and IL-6 were within the normal range in patients with AD. CONCLUSIONS: The results suggest that serum M-CSF level may provide a convenient and sensitive means for the early diagnosis of Alzheimer's disease.


Assuntos
Doença de Alzheimer/sangue , Fator Estimulador de Colônias de Macrófagos/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Interleucina-1/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/metabolismo
9.
J Phys Chem Lett ; 5(8): 1368-73, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-26269981

RESUMO

Here we designed the kinetically favored Li4Ti5O12 by modifying its crystal structure to improve intrinsic Li diffusivity for high power density. Our first-principles calculations revealed that the substituted Na expanded the oxygen framework of Li4Ti5O12 and facilitated Li ion diffusion in Li4Ti5O12 through 3-D high-rate diffusion pathway secured by Na ions. Accordingly, we synthesized sodium-substituted Li4Ti5O12 nanorods having not only a morphological merit from 1-D nanostructure engineering but also sodium substitution-induced open framework to attain ultrafast Li diffusion. The new material exhibited an outstanding cycling stability and capacity retention even at 200 times higher current density (20 C) compared with the initial condition (0.1 C).

10.
Nanoscale ; 6(2): 1005-10, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24292268

RESUMO

A nano-Si/FeSi2Ti hetero-structure has been synthesized for highly reversible Li-ion batteries by using a simple melt-spinning method. We demonstrate that this composite has a very peculiar core/shell structure in which the FeSi2Ti alloy plays various pivotal roles as a mechanically supporting backbone and as an electronic pathway for the active Si attached to its surface, and is responsible for the altered electrochemical reactions with relatively small volume expansion routes. The FeSi2Ti matrix significantly contributes to not only the stabilization of cyclic retention, but also the enhancement of conductivity, as well as a high rate capability unprecedented in research on Si-based anodes. This achievement demonstrates the potency of this novel hybrid design for electrode materials for energy storage.

11.
ChemSusChem ; 7(8): 2248-54, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24924807

RESUMO

The phase control of spinel LiNi0.5 Mn1.5 O4 was achieved through surface treatment that led to an enhancement of its electrochemical properties. Li(+) diffusion inside spinel LiNi0.5 Mn1.5 O4 could be promoted by modifying the surface structure of LiNi0.5 Mn1.5 O4 through phosphidation into a disordered phase (Fd3m) that allows facile Li(+) transport. Phosphidated LiNi0.5 Mn1.5 O4 showed a significantly enhanced electrochemical performance, even at high rates exceeding 10 C, demonstrating that the improved kinetics (related to the amount of Mn(3+) ) can render LiNi0.5 Mn1.5 O4 competitive as a high-power cathode material for electric vehicles and hybrid electric vehicles.


Assuntos
Fontes de Energia Elétrica , Compostos de Lítio/química , Lítio/química , Manganês/química , Níquel/química , Óxidos/química , Difusão , Eletrodos , Propriedades de Superfície
12.
ACS Appl Mater Interfaces ; 6(12): 9435-41, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24786736

RESUMO

We offer a brand new strategy for enhancing Li ion transport at the surface of LiFePO4/C nanofibers through noble Li ion conducting pathways built along reduced carbon webs by phosphorus. Pristine LiFePO4/C nanofibers composed of 1-dimensional (1D) LiFePO4 nanofibers with thick carbon coating layers on the surfaces of the nanofibers were prepared by the electrospinning technique. These dense and thick carbon layers prevented not only electrolyte penetration into the inner LiFePO4 nanofibers but also facile Li ion transport at the electrode/electrolyte interface. In contrast, the existing strong interactions between the carbon and oxygen atoms on the surface of the pristine LiFePO4/C nanofibers were weakened or partly broken by the adhesion of phosphorus, thereby improving Li ion migration through the thick carbon layers on the surfaces of the LiFePO4 nanofibers. As a result, the phosphidated LiFePO4/C nanofibers have a higher initial discharge capacity and a greatly improved rate capability when compared with pristine LiFePO4/C nanofibers. Our findings of high Li ion transport induced by phosphidation can be widely applied to other carbon-coated electrode materials.

13.
Chem Commun (Camb) ; 49(63): 7067-9, 2013 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-23817341

RESUMO

A multiphase composite film composed of nickel(II) hydroxide and cobalt(II) hydroxide was synthesized by a novel co-precipitation method. The film exhibited high capacitance and stable cyclic retention because of its 3D network nanostructure and high conductivity due to CoOOH evolved during cycling.

14.
ACS Appl Mater Interfaces ; 5(3): 691-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23305151

RESUMO

The morphology and electronic structure of metal oxides, including TiO(2) on the nanoscale, definitely determine their electronic or electrochemical properties, especially those relevant to application in energy devices. For this purpose, a concept for controlling the morphology and electrical conductivity in TiO(2), based on tuning by electrospinning, is proposed. We found that the 1D TiO(2) nanofibers surprisingly gave higher cyclic retention than 0D nanopowder, and nitrogen doping in the form of TiO(2)N(x) also caused further improvement. This is due to higher conductivity and faster Li(+) diffusion, as confirmed by electrochemical impedance spectra. Our findings provide an effective and scalable solution for energy storage efficiency.

15.
Nanoscale ; 4(21): 6870-5, 2012 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-23026842

RESUMO

We report on the synthesis of one-dimensional (1D) Li(4)Ti(5)O(12) nanofibers through electrospinning and their outstanding electrochemical performances. Li(4)Ti(5)O(12) with a spinel structure is a promising candidate anode material for lithium rechargeable batteries due to its well-known zero-strain merits. In order to improve the electronic properties of spinel Li(4)Ti(5)O(12), which are intrinsically poor, we processed the material into a nanofiber type of architecture to shorten the Li(+) and electron transport distance using a versatile electrospinning approach. The electrospun Li(4)Ti(5)O(12) nanofiber showed significantly enhanced discharging/charging properties, even at high rates that exceeded 10 C, demonstrating that the nanofiber offers an attractive architecture for enhanced kinetics.


Assuntos
Fontes de Energia Elétrica , Lítio/química , Nanofibras/química , Titânio/química , Técnicas Eletroquímicas , Eletrodos , Cinética , Povidona/química
16.
ACS Appl Mater Interfaces ; 4(7): 3459-64, 2012 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-22709146

RESUMO

Hollow spheres have been constructed by applying the Kirkendall effect to Sn nanocrystals. This not only accommodates the detrimental volume expansion but also reduces the Li(+) transport distance enabling homogeneous Li-Sn alloying. Hollow Sn-SnO2 nanocrystals show a significantly enhanced cyclic performance compared to Sn nanocrystal alone due to its typical structure with hollow core. Sn-SnO2/graphite nanocomposites obtained by the chemical reduction and oxidation of Sn nanocrystals onto graphite displayed very stable cyclic performance thanks to the role of graphite as an aggregation preventer as well as an electronic conductor.

17.
Nanoscale ; 4(2): 473-7, 2012 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-22095097

RESUMO

Thermal decomposition of Co(acac)(3) and Cu(acac)(2) in benzylamine leads to the formation of [100] directed Cu-doped h-CoO nanorods, which are very stable in an aqueous solution. The formation mechanism of the [100] directed Cu-doped h-CoO nanorods is fully elucidated by using first-principles calculations, demonstrating that Cu-doping not only changes the growth direction but also enhances the stability of the nanorods significantly. Evaluation of the electrochemical performance of Cu-doped h-CoO nanorods shows high initial Coulombic efficiency and ultrahigh capacity with excellent cycling performance, indicating their suitability as an anode material for next generation lithium-ion batteries.


Assuntos
Cobre/química , Cristalização/métodos , Fontes de Energia Elétrica , Lítio/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Desenho de Equipamento , Análise de Falha de Equipamento , Íons , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
18.
Chem Commun (Camb) ; 47(41): 11474-6, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-21952411

RESUMO

Phosphidated-Li(4)Ti(5)O(12) shows high capacity with a significantly enhanced kinetics opening new possibilities for ultra-fast charge/discharge of lithium rechargeable batteries. The in vitro cytotoxicity test proves its fabulous cell viability, indicating that the toxicity problem of nanoparticles can be also solved by phosphidation.


Assuntos
Fontes de Energia Elétrica , Lítio/química , Nanopartículas/química , Óxidos/química , Fósforo/química , Titânio/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Eletroquímica , Teste de Materiais , Microscopia Eletrônica de Transmissão , Nanopartículas/toxicidade , Compostos Organofosforados/química , Espectroscopia Fotoeletrônica , Ratos , Espectrometria por Raios X
19.
Artigo em Coreano | WPRIM | ID: wpr-15886

RESUMO

OBJECTIVE: During the transition to menopause, various symptoms including vasomotor symptoms and depressed mood lead to low quality of life. We investigated the effect of low-dose venlafaxine hydrochloride extended release on depressed mood and vasomotor symptoms of perimenopausal women. METHODS: 33 perimenopausal women fulfilling Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria for a depressive episode were enrolled between January 2014 and May 2014. Subjects were prescribed 37.5 mg/day or 75 mg/day venlafaxine hydrochloride according to clinician's judgement, and the dosages were maintained for 8 weeks. Depressed mood and other psychological difficulties were evaluated by using Hamilton Rating Scale for Depression (HAMD), Hamilton Rating Scale for Anxiety (HAMA), Clinical Global Impression-Severity. Climacteric symptoms including vasomotor symptoms were evaluated by using Greene Climacteric Scale (GCS). For statistical analysis, paired t-test was used. RESULTS: Significant decreases in HAMD, HAMA, GCS scores were observed after 2 weeks of treatment and the trends continued until the end of the study. The scores of HAMD significantly decreased, 28 of them reached remission (HAMD < or =7). The scores on vasomotor symptoms of GCS after 8 week treatment significantly decreased compared to baseline (13.1+/-5.0, p<0.01). CONCLUSION: These results suggest that venlafaxine hydrochloride is effective and tolerable treatment option for vasomotor symptoms and depressed mood in perimenopausal women. To validate our results, furthur studies with double-blind, placebo controlled will be needed.


Assuntos
Feminino , Humanos , Ansiedade , Climatério , Depressão , Manual Diagnóstico e Estatístico de Transtornos Mentais , Menopausa , Qualidade de Vida , Cloridrato de Venlafaxina
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