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1.
Small ; 20(24): e2308522, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38161261

RESUMO

The Ni and Fe dual-atom catalysts still undergo strikingly attenuation under high current density and high overpotential. To ameliorate the issue, the ionic liquids with different cations or anions are used in this work to regulate the micro-surface of nitrogen-doped carbon supported Ni and Fe dual-atom sites catalyst (NiFe-N-C) by an impregnation method. The experimental data reveals the dual function of ionic liquids, which enhances CO2 adsorption ability and modulates electronic structure, facilitating CO2 anion radical (CO2 •¯) stabilization and decreasing onset potential. The theoretical calculation results prove that the attachment of ionic liquids modulates electronic structure, reduces energy barrier of CO2 •¯ formation, and enhances overall ECR performance. Based on these merits, BMImPF6 modified NiFe-N-C (NiFe-N-C/BMImPF6) achieves the high CO faradaic efficiency of 91.9% with a CO partial current density of -120 mA cm-2 at -1.0 V. When the NiFe-N-C/BMImPF6 is assembled as cathode of Zn-CO2 battery, it delivers the highest power density of 2.61 mW cm-2 at 2.57 mA cm-2 and superior cycling stability. This work will afford a direction to modify the microenvironment of other dual-atom catalysts for high-performance CO2 electroreduction.

2.
Small ; : e2403831, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949398

RESUMO

Lithium metal batteries are regarded as promising candidates for next-generation energy storage systems. However, their anodes are susceptible to interfacial instability due to significant volume changes, which significantly impacts the cycle life of lithium metal batteries. Here, a rapid method for the fabrication of 3D-hosts with interface modified layers is reported. A simple infiltration and heating process enables the transformation of copper foam into Zn-BDC-modified copper foam within 1 min, rendering it suitable for use as a current collector for lithium metal anodes. The Zn-BDC nanosheets with high lithiophilicity are uniformly distributed on the surface of the current collector, facilitating the uniform deposition of lithium and reducing the volume change. Consequently, the half cell exhibits a remarkably low overpotential (26 mV) at a current-density of 4 mA cm-2 and is cycled stably for 1000 h. Furthermore, it demonstrates a significant enhancement in performance in the LiFePO4 full cell. This study provides a crucial reference on the connection between the interfacial modification of the current collector and the lithium deposition behavior, which promotes the practicalization of lithium metal anodes.

3.
Small ; 19(38): e2302015, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37222119

RESUMO

Heterojunctions are a promising class of materials for high-efficiency bifunctional oxygen electrocatalysts in both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). However, the conventional theories fail to explain why many catalysts behave differently in ORR and OER, despite a reversible path (* O2 ⇋* OOH⇋* O⇋* OH). This study proposes the electron-/hole-rich catalytic center theory (e/h-CCT) to supplement the existing theories, it suggests that the Fermi level of catalysts determines the direction of electron transfer, which affects the direction of the oxidation/reduction reaction, and the density of states (DOS) near the Fermi level determines the accessibility for injecting electrons and holes. Additionally, heterojunctions with different Fermi levels form electron-/hole-rich catalytic centers near the Fermi levels to promote ORR/OER, respectively. To verify the universality of the e/h-CCT theory, this study reveals the randomly synthesized heterostructural Fe3 N-FeN0.0324 (Fex N@PC with DFT calculations and electrochemical tests. The results show that the heterostructural F3 N-FeN0.0324 facilitates the catalytic activities for ORR and OER simultaneously by forming an internal electron-/hole-rich interface. The rechargeable ZABs with Fex N@PC cathode display a high open circuit potential of 1.504 V, high power density of 223.67 mW cm-2 , high specific capacity of 766.20 mAh g-1 at 5 mA cm-2 , and excellent stability for over 300 h.

4.
Nanotechnology ; 30(33): 335701, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30995631

RESUMO

The iron oxide-based anode materials are widely studied and reported due to their abundance, low cost, high energy density and environmental friendliness for lithium ion batteries (LIBs). However, the application of LIBs is always limited by the poor rate capability and stability. In order to tackle these issues, a novel material with carbon-encapsulated Fe3O4 nanorods stuck together by multilevel porous carbon (Fe3O4@C/PC) is prepared through directly carbonizing the Fe-based metal-organic framework under a nitrogen atmosphere. This novel material shows a high specific capacity and rate performance. The initial specific capacity can reach 1789 mAh g-1 at a current density of 0.1 A g-1, and the specific capacity still remains 1105.3 mAh g-1 and 783.5 mAh g-1 after 150 cycles at the current densities of 0.1 A g-1 and 1 A g-1, respectively. Even under a current density as high as 12 A g-1, the specific capacity can achieve 309 mAh g-1 after 2000 cycles with an average attenuation rate of 0.019% per cycle. Overall, the simple strategy, low cost and high capacity can make the practical application possible.

5.
Nanomedicine ; 18: 380-390, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30428334

RESUMO

The lack of effective therapies mandates the development of new treatment strategies for ischemic stroke. The NR2B9c peptide can prevent N-Methyl-D-aspartate receptor (NMDAR)-mediated neurotoxicity induced by ischemia without affecting essential NMDAR activity and brings hope for stroke therapy. However, it is very difficult for NR2B9c to cross by itself the blood-brain barrier (BBB) and the neuron membrane. To provide a suitable delivery for unleashing the therapeutic potential of NR2B9c, in consideration of a high affinity of wheat germ agglutinin (WGA) for WGA receptors abundantly present on olfactory epithelium and neuronal surface, we developed WGA-modified nanoparticles carrying NR2B9c (NR2B9c-WGA-NPs). Following intranasal administration, NR2B9c-WGA-NPs are able to bypass the BBB and effectively transport NR2B9c into the brain and neuron, and therefore can protect neurons against excitotoxicity, reduce ischemic brain injury in rats and ameliorate their neurological function deficits. The intranasal administration of NR2B9c-WGA-NPs may serve as a practical stroke therapy.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Neurônios/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Peptídeos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Administração Intranasal , Animais , Isquemia Encefálica/complicações , Humanos , Nanopartículas/ultraestrutura , Neurônios/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Ratos , Acidente Vascular Cerebral/complicações , Distribuição Tecidual/efeitos dos fármacos , Aglutininas do Germe de Trigo/química
6.
J Neurosci ; 34(40): 13535-48, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25274829

RESUMO

Stroke is a major public health concern. The lack of effective therapies heightens the need for new therapeutic targets. Mammalian brain has the ability to rewire itself to restore lost functionalities. Promoting regenerative repair, including neurogenesis and dendritic remodeling, may offer a new therapeutic strategy for the treatment of stroke. Here, we report that interaction of neuronal nitric oxide synthase (nNOS) with the protein postsynaptic density-95 (PSD-95) negatively controls regenerative repair after stroke in rats. Dissociating nNOS-PSD-95 coupling in neurons promotes neuronal differentiation of neural stem cells (NSCs), facilitates the migration of newborn cells into the injured area, and enhances neurite growth of newborn neurons and dendritic spine formation of mature neurons in the ischemic brain of rats. More importantly, blocking nNOS-PSD-95 binding during the recovery stage improves stroke outcome via the promotion of regenerative repair in rats. Histone deacetylase 2 in NSCs may mediate the role of nNOS-PSD-95 association. Thus, nNOS-PSD-95 can serve as a target for regenerative repair after stroke.


Assuntos
Infarto da Artéria Cerebral Média/cirurgia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Células-Tronco Neurais/transplante , Óxido Nítrico Sintase Tipo I/metabolismo , Regeneração/fisiologia , Animais , Encéfalo/patologia , Encéfalo/ultraestrutura , Diferenciação Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Técnicas de Cocultura , Modelos Animais de Doenças , Proteína 4 Homóloga a Disks-Large , Embrião de Mamíferos , Glucose/deficiência , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Hipóxia/fisiopatologia , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Neurônios/metabolismo , Neurônios/patologia , Neurônios/ultraestrutura , Óxido Nítrico Sintase Tipo I/genética , Ratos , Ratos Sprague-Dawley
7.
Stroke ; 46(5): 1352-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25851770

RESUMO

BACKGROUND AND PURPOSE: Previous studies reported that Tat-NR2B9c, a peptide disrupting the N-methyl-d-aspartate receptor-postsynaptic density protein-95 interaction, reduced ischemic damage in the acute phase after stroke. However, its effect in the subacute phase is unknown. The aim of this study is to determine whether disrupting the N-methyl-d-aspartate receptor-postsynaptic density protein-95 interaction in the subacute phase promotes recovery after stroke. METHODS: Studies were performed on Sprague-Dawley rats or nNOS(-/-) mice, and experimental ischemic stroke was induced by middle cerebral artery occlusion. Animals were treated with drugs starting at day 4 after ischemia. Sensorimotor functions and spatial learning and memory ability were assessed after drug treatment. Then, rats were euthanized for morphological observation and biochemical tests. RESULTS: Disrupting the N-methyl-d-aspartate receptor-postsynaptic density protein-95 interaction with Tat-HA-NR2B9c significantly ameliorated the ischemia-induced impairments of spatial memory and sensorimotor functions in rats during subacute stage but did not improve stroke outcome in nNOS(-/-) mice. Consistent with the functional recovery, Tat-HA-NR2B9c substantially increased neurogenesis in the dentate gyrus and dendritic spine density of mature neurons in the motor cortex of rats, meanwhile, reversed the ischemia-induced formation of S-nitrosylation-cyclin-dependent kinase 5 and increased cyclin-dependent kinase 5 activity in ipsilateral hippocampus. However, directly blocking N-methyl-d-aspartate receptors with MK-801 or Ro 25-6981 did not show the beneficial effects above. CONCLUSIONS: Dissociating N-methyl-d-aspartate receptor-postsynaptic density protein-95 coupling by Tat-HA-NR2B9c in the subacute phase after stroke promotes functional recovery, probably because of that it increases neurogenesis and dendritic spine density of mature neurons via regulating cyclin-dependent kinase 5 in the ischemic brain.


Assuntos
Fármacos Neuroprotetores/uso terapêutico , Peptídeos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Cognição/efeitos dos fármacos , Quinase 5 Dependente de Ciclina/metabolismo , Espinhas Dendríticas/ultraestrutura , Giro Denteado/patologia , Proteína 4 Homóloga a Disks-Large , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Proteínas de Membrana/antagonistas & inibidores , Córtex Motor/patologia , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Óxido Nítrico Sintase Tipo I/metabolismo , Peptídeos/administração & dosagem , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Sensação/efeitos dos fármacos , Acidente Vascular Cerebral/prevenção & controle
8.
J Colloid Interface Sci ; 675: 207-217, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38968637

RESUMO

At present, electrochemical CO2 reduction has been developed towards industrial current density, but the high faradaic efficiency at wide potential range or large current density is still an arduous task. Therefore, in this work, the highly exposed Ni single atoms (NiNCR-0.72) was synthesized through simple metal organic frameworks (MOFs)-derived method with SiO2 protection strategy. The obtained catalyst keeps CO faradaic efficiency (FECO) above 91 % under the wide potential range, and achieves a high FECO of 96.0 % and large CO partial current density of -206.8 mA cm-2 at -0.7 V in flow cell. The experimental results and theoretical calculation disclose that NiNCR-0.72 possesses the robust structure with rich mesopore and more highly exposed Ni-N active sites under SiO2 protection, which could facilitate CO2 transportation, lower energy barrier of CO2 reduction, and raise difficulty of hydrogen evolution reaction. The protection strategy is instructive to the synthesis of other MOFs-derived metal single atoms.

9.
Chemistry ; 19(41): 13720-5, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24019135

RESUMO

PdPt bimetallic nanotubes were prepared by the self-assembly of Pt and Pd on Te nanowires at room temperature. The morphologies of the as-prepared PdPt nanotubes were investigated by scanning electron microscopy and transmission electron microscopy, and the results display a large amount of PdPt bimetallic nanotubes with a diameter of 10-20 nm and a length of several micrometers. The composition and structure of the nanotubes were characterized by X-ray diffraction, high-resolution transmission electron microscopy, scanning transmission electron microscopy, and energy spectrum analysis, and the results display uniform compositional distributions of both elements (Pd and Pt). The mechanism of the formation of the nanotube structure was supposed. The electrocatalytic performance of PdPt nanotubes were studied by cyclic voltammetry and chronoamperometry. Electrochemical results show that the as-prepared PdPt nanotube catalysts have not only high activity but also good stability for ethanol oxidation in alkaline medium.

10.
Nat Commun ; 14(1): 6407, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828005

RESUMO

Extreme fast charging of Ampere-hour (Ah)-scale electrochemical energy storage devices targeting charging times of less than 10 minutes are desired to increase widespread adoption. However, this metric is difficult to achieve in conventional Li-ion batteries due to their inherent reaction mechanism and safety hazards at high current densities. In this work, we report 1 Ah soft-package potassium-ion hybrid supercapacitors (PIHCs), which combine the merits of high-energy density of battery-type negative electrodes and high-power density of capacitor-type positive electrodes. The PIHC consists of a defect-rich, high specific surface area N-doped carbon nanotube-based positive electrode, MnO quantum dots inlaid spacing-expanded carbon nanotube-based negative electrode, carbonate-based non-aqueous electrolyte, and a binder- and current collector-free cell design. Through the optimization of the cell configuration, electrodes, and electrolyte, the full cells (1 Ah) exhibit a cell voltage up to 4.8 V, high full-cell level specific energy of 140 Wh kg-1 (based on the whole mass of device) with a full charge of 6 minutes. An 88% capacity retention after 200 cycles at 10 C (10 A) and a voltage retention of 99% at 25 ± 1 °C are also demonstrated.

11.
Protein Expr Purif ; 85(2): 239-45, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22944204

RESUMO

To design a peptide disrupting the interaction between N-methyl-d-aspartate receptors-2B (NR2B) and postsynaptic density protein-95 (PSD-95), a gene fragment encoding a chimeric peptide was constructed using polymerase chain reaction and ligated into a novel expression vector for recombinant expression in a T7 RNA polymerase-based expression system. The chimeric peptide contained a fragment of the cell membrane transduction domain of the human immunodeficiency virus type1 (HIV-1) Tat, a influenza virus hemagglutinin (HA) epitope-tag, and the C-terminal 9 amino acids of NR2B (NR2B9c). We named the chimeric peptide Tat-HA-NR2B9c. The expression plasmid contained a gene fragment encoding the Tat-HA-NR2B9c was ligated to the C-terminal fragment of l-asparaginase (AnsB-C) via a unique acid labile Asp-Pro linker. The recombinant fusion protein was expressed in inclusion body in Escherichia coli under isopropyl ß-d-1-thiogalactopyranoside (IPTG) and purified by washing with 2M urea, solubilizing in 4M urea, and then ethanol precipitation. The target chimeric peptide Tat-HA-NR2B9c was released from the fusion partner following acid hydrolysis and purified by isoelectric point precipitation and ultrafiltration. SDS-PAGE analysis and MALDI-TOF-MS analysis showed that the purified Tat-HA-NR2B9c was highly homogeneous. Furthermore, we investigated the effects of Tat-HA-NR2B9c on ischemia-induced cerebral injury in the rats subjected to middle cerebral artery occlusion (MCAO) and reperfusion, and found that the peptide reduced infarct size and improved neurological functions.


Assuntos
Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Receptores de N-Metil-D-Aspartato/isolamento & purificação , Proteínas Recombinantes de Fusão/isolamento & purificação , Animais , Isquemia Encefálica/tratamento farmacológico , Infarto Cerebral/tratamento farmacológico , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Masculino , Camundongos , Peptídeos/genética , Peptídeos/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/biossíntese , Receptores de N-Metil-D-Aspartato/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo
12.
Hum Vaccin Immunother ; 18(6): 2143154, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36412232

RESUMO

Previous clinical studies had not shown expected results in advanced pancreatic cancer (APC) with single-agent checkpoint inhibitors. Until the present day, little is known about their performance in real-world settings. So, in this study, we investigate the ICIs' efficacy and safety in Chinese APC patients. Patients with APC who received ICIs between November 2018 to June 2021 were enrolled in this retrospective study. The efficacy end points included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR) and adverse events (AEs). This study included 104 patients and the median OS (mOS) and median PFS (mPFS) were 9.1 and 5.4 months, respectively. In the subgroup analyses, the mOS was longer for patients receiving combined radiotherapy than for those that didn't (13.8 vs 7.0 months, p < .001), whereas the mPFS was also longer, and the ORR and DCR were higher. Specifically, the mOS was longer for patients who had received a combination of chemotherapy than for those combined with targeted therapy (11.6 vs 5.6 months, p = .002), with the mPFS being also longer. ICIs as a first-line treatment could resulted to better survival. The mOS was longer for patients with a high TMB compared to those with low (19.3 vs 7.2 months, p = .004), whereas AEs were considered to be tolerable. The combination therapy of ICIs was proved to be safe and effective for treating APC, especially the combination of chemotherapy and radiotherapy, which would benefit from additional prospective studies.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias Pancreáticas , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Estudos Prospectivos , População do Leste Asiático , Estudos Retrospectivos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas
13.
Int J Clin Pharm ; 43(1): 229-235, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32920684

RESUMO

Background Beers criteria have been into the mainstay to characterize the potentially inappropriate medication since its first publication, but the recent version, Beers 2019, is yet to be validated by clinical studies nationally. Objective To identify the prevalence and the predictors of potentially inappropriate medications in hospitalized geriatric patients based on the Beers 2019 and 2015 criteria. Setting Nanjing Drum Tower Hospital, a 3000-bed tertiary care teaching hospital in China. Method We conducted a cross-sectional study from July 1, 2018 to December 31, 2018. Data from all hospitalized patients aged ≥ 65 years were collected from the hospital database. Inappropriate prescriptions were identified using the Beers 2019 criteria and the Beers 2015 criteria. Main outcome measure Prevalence Ratio (PR) and predictors of potentially inappropriate medications. Results The prevalence of inappropriate prescriptions based on the Beers 2019 criteria was 64.80%. This result was slightly higher than that of the Beers 2015 criteria (64.31%). The most commonly encountered inappropriate prescriptions identified using the two criteria were proton-pump inhibitors. The kappa coefficient was 0.826 (p < 0.001) indicating a strong coherence between the two criteria. The most important factor associated with inappropriate medications use was the number of prescribed drugs (PR 5.17, 95% CI 2.89-8.43; PR 4.58, 95% CI 1.93-7.25). Conclusion This study showed a high prevalence of potentially inappropriate medication in the Chinese geriatric population, which was associated with the number of prescribed drugs. The predictors identified in this research might help pharmacists to detect high-risk drugs and intervene in time.


Assuntos
Prescrição Inadequada , Lista de Medicamentos Potencialmente Inapropriados , Idoso , China/epidemiologia , Estudos Transversais , Humanos , Polimedicação , Prevalência
14.
J Colloid Interface Sci ; 593: 408-416, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33744548

RESUMO

Potassium-ion batteries (PIBs) is one of the most promising alternatives for Lithium-ion batteries (LIBs) due to the low-cost and abundant potassium reserves. However, the electrochemical performances of PIBs were seriously hindered by the larger radius of potassium ions, resulting in a slow kinetic during the electrochemical reaction, especially in the PIB anodes. In the study, we propose FeS nanodots embedded S-doped porous carbon (FeS@SPC) synthesized by a simple self-template method for the storage of potassium-ions. The FeS nanodots with an average diameter of 5 nm are uniformly distributed in S-doped porous carbon nanosheets. When the FeS@SPC was used as the anode in PIBs, the unique structure of FeS@SPC can relieve the agglomeration and volume expansion of FeS effectively during the charge-discharge process. Even after 3000 cycles, the FeS nanodots are still uniformly embedded in porous carbon without agglomeration. Ascribed to the merits, the FeS@SPC exhibits a reversible capacity of 309 mAh g-1 at 0.1 A g-1 after 100 cycles and 232 mAh g-1 at 1 A g-1 after 3000 cycles. The excellent electrochemical performance of FeS@SPC is attributed to the synergistic effects of FeS nanodots and S-doped porous carbon, which facilitated the diffusion of electrolyte and accelerated the migration of potassium ions. Moreover, theoretical calculation results also suggest that the van der waals heterostructure of FeS@SPC displays higher adsorption energy for potassium ions than that of S-doped graphene, indicating the suitability of FeS@SPC for K storage.

16.
Chem Commun (Camb) ; 56(78): 11689-11692, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33000778

RESUMO

Heteroatom-doped 3D porous carbon materials have been synthesized by utilizing hydroxyapatite in pig bones as a self-template and used as electrode materials for symmetric supercapacitors, which exhibit ultra-high energy density both in an aqueous electrolyte and organic electrolyte, showing great potential applications in the next generation of energy storage and conversion devices.

17.
Exp Neurol ; 311: 80-87, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30253135

RESUMO

Oxaliplatin is a commonly used chemotherapy drug, which can produce acute and chronic peripheral neurotoxicity. Currently, there is no good therapeutic drug in clinic. Excessive stimulation of N-methyl-d-aspartate receptors (NMDARs) is crucial for the transmission of pain signals. However, directly inhibiting NMDARs can cause severe side effects because they have key physiological functions in the Central nervous system (CNS). Several years ago, we prepared a polypeptide Tat-HA-NR2B9c which can disturb NMDARs-postsynaptic density protein-95 (PSD-95) interaction. In this study, we studied whether Tat-HA-NR2B9c could be an effective treatment for oxaliplatin-induced neuropathic pain. To conform it, a rat model of oxaliplatin-induced neuropathic was established, and analgesic effect of Tat-HA-NR2B9c was studied. Here, we show that oxaliplatin induces the interaction of NMDARs with PSD-95. Uncoupling the complex by Tat-HA-NR2B9c has potent analgesic effect in oxaliplatin-induced cold hyperalgesia and mechanical allodynia without suppressing general behavioral. Tat-HA-NR2B9c neither inhibits NMDARs function nor impacts antitumor activity of oxaliplatin. Thus, this new drug may serve as a treatment for oxaliplatin-induced neuropathic pain, perhaps without major side effects.


Assuntos
Neuralgia/induzido quimicamente , Neuralgia/prevenção & controle , Fármacos Neuroprotetores/administração & dosagem , Oxaliplatina/toxicidade , Peptídeos/administração & dosagem , Animais , Antineoplásicos/toxicidade , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Injeções Espinhais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neuralgia/metabolismo , Técnicas de Cultura de Órgãos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
19.
ACS Nano ; 12(1): 208-216, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29286637

RESUMO

Herein, we reported a special Fe-N-doped double-shelled hollow carbon microsphere (Fe-N-DSC) which was prepared by a facile, in situ polymerization followed by pyrolysis. With porous ferroferric oxide (Fe3O4) hollow microspheres as the templates, where pyrrole monomers were dispersed around the outer surface and prefilled the interior space. By adding hydrochloric acid, Fe3+ ions were released to initiate polymerization of pyrrole on both the outer and inner surfaces of Fe3O4 microspheres until they were completely dissolved, resulting in the Fe-containing polypyrrole double-shelled hollow carbon microspheres (Fe-PPY-DSC). The Fe-PPY-DSC was then pyrolyzed to generate the Fe-N-DSC. The Fe3O4 hollow microspheres played trifunctional roles, i.e., the template to prepare a double-shelled hollow spherical structure, the initiator (i.e., Fe3+ ions) for the polymerization of pyrrole, and the Fe source for doping. The Fe-N-DSC exhibited a superior catalytic activity for oxygen reduction as comparable to commercial Pt/C catalysts in both alkaline and acidic media. The high catalytic performance was ascribed to the special porous double-shelled hollow spherical structure, which provided more active sites and was beneficial to a high-flux mass transportation.

20.
Front Neurol ; 8: 509, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29018405

RESUMO

Transient global ischemia (TGI) is a major public health problem, and it heightens the need of effective treatments. The present study was undertaken to investigate whether recombinant polypeptide Tat-HA-NR2B9c improves spatial learning and memory deficits in rats after TGI. Rats were subjected to 20-min ischemia induced by four-vessel occlusion (4-VO) method and daily injected with Tat-HA-NR2B9c (1.12 mg/kg) for 1 week. Tat-HA-NR2B9c increased CREB activity, upregulated B-cell lymphoma-2 (Bcl-2) expression after treated for 24 h. There was a significant increase in dendrite spine density in hippocampal CA1 region and BrdU-positive cells and BrdU/NeuN-positive cells in the dentate gyrus after Tat-HA-NR2B9c treatment, compared with ischemia group at postischemic day 28. Inhibition of the CREB activation by recombinant lentivirus, LV-CREB133-GFP, abolished the upregulation effects of Tat-HA-NR2B9c on Bcl-2 expression. Moreover, Tat-HA-NR2B9c improved the impaired spatial learning and memory ability in Morris water maze. These results suggest that Tat-HA-NR2B9c substantially ameliorated the TGI-induced loss of dendrite spine in hippocampal CA1, increased neurogenesis in dentate gyrus, and significantly improved cognitive abilities by the CREB pathway in rats after transient global cerebral ischemia. It may be served as a treatment for TGI.

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