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1.
Biochem Biophys Res Commun ; 721: 150128, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-38776831

RESUMEN

PURPOSE: Chronic stress is a significant risk factor for mood disorders such as depression, where synaptic plasticity plays a central role in pathogenesis. Transient Receptor Potential Vanilloid Type-2 (TRPV2) Ion Channels are implicated in hypothalamic-pituitary-adrenal axis disorders. Previous proteomic analysis indicated a reduction in TRPV2 levels in the chronic unpredictable mild stress (CUMS) rat model, yet its role in synaptic plasticity during depression remains to be elucidated. This study aims to investigate TRPV2's role in depression and its underlying mechanisms. METHODS: In vivo and in vitro experiments were conducted using the TRPV2-specific agonist probenecid and ERK1/2 inhibitors SCH772984. In vivo, rats underwent six weeks of CUMS before probenecid administration. Depressive-like behaviors were assessed through behavioral tests. ELISA kits measured 5-HT, DA, NE levels in rat hippocampal tissues. Hippocampal morphology was examined via Nissl staining. In vitro, rat hippocampal neuron cell lines were treated with ERK1/2 inhibitors SCH772984 and probenecid. Western blot, immunofluorescence, immunohistochemical staining, and RT-qPCR assessed TRPV2 expression, neurogenesis-related proteins, synaptic markers, and ERK1/2-CREB-BDNF signaling proteins. RESULTS: Decreased hippocampal TRPV2 levels were observed in CUMS rats. Probenecid treatment mitigated depressive-like behavior and enhanced hippocampal 5-HT, NE, and DA levels in CUMS rats. TRPV2 activation countered CUMS-induced synaptic plasticity inhibition. Probenecid activated the ERK1/2-CREB-BDNF pathway, suggesting TRPV2's involvement in this pathway via ERK1/2. CONCLUSION: These findings indicate that TRPV2 activation offers protective effects against depressive-like behaviors and enhances hippocampal synaptic plasticity in CUMS rats via the ERK1/2-CREB-BDNF pathway. TRPV2 emerges as a potential therapeutic target for depression.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Hipocampo , Sistema de Señalización de MAP Quinasas , Plasticidad Neuronal , Ratas Sprague-Dawley , Estrés Psicológico , Canales Catiónicos TRPV , Animales , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/antagonistas & inhibidores , Plasticidad Neuronal/efectos de los fármacos , Masculino , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Estrés Psicológico/complicaciones , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Hipocampo/metabolismo , Hipocampo/efectos de los fármacos , Ratas , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Depresión/metabolismo , Depresión/tratamiento farmacológico , Enfermedad Crónica , Probenecid/farmacología
2.
Neurosci Bull ; 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37973720

RESUMEN

Neuroinflammation mediated by microglia and oxidative stress play pivotal roles in the development of chronic temporal lobe epilepsy (TLE). We postulated that kainic acid (KA)-Induced status epilepticus triggers microglia-dependent inflammation, leading to neuronal damage, a lowered seizure threshold, and the emergence of spontaneous recurrent seizures (SRS). Extensive evidence from our laboratory suggests that dextromethorphan (DM), even in ultra-low doses, has anti-inflammatory and neuroprotective effects in many animal models of neurodegenerative disease. Our results showed that administration of DM (10 ng/kg per day; subcutaneously via osmotic minipump for 4 weeks) significantly mitigated the residual effects of KA, including the frequency of SRS and seizure susceptibility. In addition, DM-treated rats showed improved cognitive function and reduced hippocampal neuronal loss. We found suppressed microglial activation-mediated neuroinflammation and decreased expression of hippocampal gp91phox and p47phox proteins in KA-induced chronic TLE rats. Notably, even after discontinuation of DM treatment, ultra-low doses of DM continued to confer long-term anti-seizure and neuroprotective effects, which were attributed to the inhibition of microglial NADPH oxidase 2 as revealed by mechanistic studies.

3.
Neuroscience ; 526: 97-106, 2023 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-37352966

RESUMEN

Brain injury is a major cause of death and disability after cardiac arrest (CA). Previous studies have shown that activating GABAB receptors significantly improves neurological function after CA, but the mechanism of this neuronal protection of damaged neurons remains unclear. Thus, the present study aimed to investigate whether GABAB receptor activation protects against neuronal injury and to reveal the underlying protective mechanisms. In this study, rats underwent 10 min of asphyxia to induce CA, and SH-SY5Y cells were subjected to oxygen and glucose deprivation/reoxygenation (OGD/R) to establish in vivo and in vitro models of hypoxic neuronal injury. Differential gene expression between CA rats and sham-operated rats was identified using RNA-seq. TUNEL and Nissl staining were used to evaluate cortical neuron damage, while Western blotting, qRT-PCR, and immunofluorescence assays were conducted to measure pyroptosis-related indicators. Furthermore, cellular models with high expression of caspase-11 were established to reveal the novel molecular mechanisms by which GABAB receptor activation exerts neuroprotective effects. Intriguingly, our results showed that caspase-11 and GSDMD were highly expressed in rats experiencing cardiac arrest. Specifically, GSDMD was expressed in neurons in the M1 area of the cerebral cortex. Moreover, activation of the GABAB receptor exerted a protective effect on neurons both in vivo and in vitro. Baclofen attenuated caspase-11 activation and neuronal pyroptosis after CA, and the anti-neuronal pyroptosis effect of baclofen was abolished by overexpression of caspase-11 in neuronal cells. In conclusion, GABAB receptor activation may play a neuroprotective role by alleviating neuronal pyroptosis through a mechanism involving caspase-11.


Asunto(s)
Lesiones Encefálicas , Neuroblastoma , Daño por Reperfusión , Ratas , Humanos , Animales , Piroptosis/fisiología , Baclofeno/farmacología , Neuroblastoma/metabolismo , Neuronas/metabolismo , Lesiones Encefálicas/metabolismo , Caspasas/metabolismo , Daño por Reperfusión/metabolismo
4.
Front Cell Dev Biol ; 11: 919297, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37123418

RESUMEN

Introduction: Chronic stress exposure is the main environmental factor leading to cognitive impairment, but the detailed molecular mechanism is still unclear. Adenosine Deaminase acting on double-stranded RNA1(ADAR1) is involved in the occurrence of chronic stress-induced cognitive impairment. In addition, dopamine and Adenosine 3'5'-monophosphate-regulated phospho-protein (DARPP-32) gene variation affects cognitive function. Therefore, we hypothesized that ADAR1 plays a key role in chronic stress-induced cognitive impairment by acting on DARPP-32. Methods: In this study, postnatal 21-day-old male BALB/c mice were exposed to chronic unpredictable stressors. After that, the mice were treated with ADAR1 inducer/inhibitor. The cognitive ability and cerebral DARPP-32 protein expression of BALB/c mice were evaluated. In order to explore the link between ADAR1 and DARPP-32, the effects of ADAR1 high/low expression on DARPP-32 protein expression in vitro were detected. Results: ADAR1 inducer alleviates cognitive impairment and recovers decreased DARPP-32 protein expression of the hippocampus and prefrontal cortex in BALB/c mice with chronic unpredictable stress exposure. In vivo and in vitro studies confirm the results predicted by bio-informatics; that is, ADAR1 affects DARPP-32 expression via miR-874-3p. Discussion: The results in this study demonstrate that ADAR1 affects the expression of DARPP-32 via miR-874-3p, which is involved in the molecular mechanism of pathogenesis in chronic unpredictable stress-induced cognitive impairment. The new findings of this study provide a new therapeutic strategy for the prevention and treatment of stress cognitive impairment from epigenetics.

5.
Neurochem Res ; 48(6): 1737-1754, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36670238

RESUMEN

Major depressive disorder (MDD) refers to a widespread psychiatric disorder. Astrocytes play a pivotal role in regulating inflammation which is a well-acknowledged key component in depression pathogenesis. However, the effects of the neuroinflammation-inducing A1-like astrocytes on MDD are still unknown. TWIK-related K+ channel 1 (TREK-1) has been demonstrated to regulate the action of antidepressants. Nevertheless, its mechanisms and effects on A1-like astrocyte stimulation in MDD are not clear. Therefore, we conducted in vivo and in vitro experiments using TREK-1 specific inhibitor spadin. In vivo, rats were subjected to a 6-week chronic unpredictable mild stress (CUMS) followed by spadin treatment. Behavioral tests were employed to surveil depressive-like behaviors. Hippocampal proteomic analysis was carried out with the purpose of identifying differentially expressed proteins after CUMS and spadin treatments. In vitro, astrocyte-conditioned medium and spadin were used to treat rat astrocyte cell line. The activated microglia, inflammatory factors, A1 astrocyte markers, and activated nuclear factor kappa B (NF-κB) pathway were later analyzed using immunofluorescence, western blot, and RT-qPCR. Our findings indicated that blockage of TREK-1 reduced CUMS-induced depressive-like behavior in rats, inhibited the microglial stimulation, reduced inflammatory factor levels, and suppressed the activation of A1-like reactive astrocytes in the hippocampus. We also verified that the suppression of A1-like astrocytes by spadin necessitated the NF-κB pathway. According to the findings, blocking TREK-1 inhibited the activation of A1-like reactive astrocytes via the NF-κB signaling pathway in MDD. Our study preliminarily identifies a novel antidepressant mechanism of TREK-1 action and provides a therapeutic path for MDD.


Asunto(s)
Trastorno Depresivo Mayor , Canales de Potasio de Dominio Poro en Tándem , Ratas , Animales , Trastorno Depresivo Mayor/tratamiento farmacológico , FN-kappa B/metabolismo , Astrocitos/metabolismo , Potasio/metabolismo , Proteómica , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Transducción de Señal , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Depresión/tratamiento farmacológico , Depresión/etiología , Estrés Psicológico/metabolismo , Hipocampo/metabolismo
6.
Nanomaterials (Basel) ; 12(8)2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35457998

RESUMEN

Prussian blue attracts the attention of many researchers as a promising candidate for use in sodium-ion battery cathodes due to its open frameworks and high working potential. However, the interstitial water in its crystal structure and its poor electronic conductivity limits its performance in practical sodium-ion batteries. Here, acid-assisted ball milling synthesis was employed as a versatile method for the production of surface-modified Prussian blue. With (CH3COO)2Fe being used as the raw material, the Prussian blue produced using ball milling synthesis was modified by the carboxyl functional group on its surface, which resulted in lower interstitial water content and enhanced electrochemical cycling performance. In addition, ball milling synthesis provided the as-prepared Prussian blue with a large surface area, improving its electrochemical rate performance. When used as the cathode of sodium-ion batteries, as-prepared Prussian blue delivered a specific capacity of 145.3 mAh g-1 at 0.2 C and 113.7 mAh g-1 at 1 C, maintaining 54.5% of the initial capacity after 1000 cycles at 1 C (1 C = 170 mA g-1). Furthermore, a solid-state sodium-ion battery was mounted, with as-prepared Prussian blue being employed as the cathode and Na metal as the anode, which delivered a high specific capacity of 128.7 mAh g-1 at 0.2 C. The present study put forward an effective solution to overcome the limitations of Prussian blue for its commercial application.

7.
Neurobiol Stress ; 15: 100396, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34568523

RESUMEN

Adenosine deaminase acting on RNA1 (ADAR1) is a newly discovered epigenetic molecule marker that is sensitive to environmental stressors. A recent study has demonstrated that ADAR1 affects BDNF expression via miR-432 and is involved in antidepressant action. However, the detailed molecular mechanism is still unclear. We have uncovered a new molecular mechanism showing the involvement of miR-432 and circ_0000418 in mediating the antidepressant action of ADAR1. We demonstrate that the ADAR1 inducer (IFN-γ) alleviates the depressive-like behaviors of BALB/c mice treated with chronic unpredictable stress (CUS) exposure. Moreover, both in vivo and in vitro studies show that ADAR1 differently impacts miR-432 and circ_0000418 expressions. Furthermore, the in vitro results demonstrate that circ_0000418 oppositely affects BDNF expression. Together, our results indicate that ADAR1 affects CUS-induced depressive-like behavior and BDNF expression by acting on miR-432 and circ_0000418. Elucidation of this new molecular mechanism will not only provide insights into further understanding the important role of ADAR1 in stress-induced depressive-like behavior but also suggest a potential therapeutic strategy for developing novel anti-depressive drugs.

8.
Behav Brain Res ; 402: 113087, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33412228

RESUMEN

Brain-derived neurotrophic factor (BDNF) is a biomarker of depression. Recent studies have found adenosine deaminase acting on RNA1 (ADAR1) is a novel target being sensitive to stress at epigenetic level. The epigenetic regulation mechanism of stress-related depression is still unclear so far. To explore the potential regulating mechanism of ADAR1 on BDNF, over and low expression of ADAR1 in PC12 and SH-SY5Y cell lines are prepared. In the meanwhile, chronic unpredictable stress (CUS) mice are treated with ADAR1 inducer (interferon-γ, IFN-γ). ADAR1 regulates BDNF expression, which is proven by that over and low expressions of ADAR1 increase and decrease BDNF mRNA and protein respectively in vitro. Additionally, ADAR1 inducer alleviates the depressive-like behavior of CUS mice by recovering the decreased BDNF protein in brain and serum. Moreover, over and low expressions of ADAR1 reduce and enhance microRNA-432 (miR-432) expression respectively in vitro. Furtherly, over and low miR-432 expressions lead to decreased and increased BDNF and ADAR1 mRNA, protein and immunoreactivity respectively in vitro. The above results demonstrate that ADAR1 is involved in antidepressant action by regulating BDNF via miR-432. Those novel findings can provide a new idea for the study of epigenetic regulation mechanism, early diagnosis, and effective treatment of stress-related depression.


Asunto(s)
Adenosina Desaminasa/metabolismo , Conducta Animal/fisiología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Depresión/metabolismo , Epigénesis Genética/fisiología , MicroARNs/metabolismo , Estrés Psicológico/metabolismo , Adenosina Desaminasa/efectos de los fármacos , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Humanos , Interferón gamma/administración & dosificación , Masculino , Ratones , Ratones Endogámicos BALB C , Células PC12 , Ratas
9.
Brain Res ; 1746: 146945, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32531223

RESUMEN

Currently, there is no efficacious pharmacological treatment for traumatic brain injury (TBI). Previous studies revealed that L-lactate preconditioning has shown rich neuroprotective effects against cerebral ischemia, and therefore has the potential to improve neurological outcomes after TBI. L-lactate played a neuroprotective role by activating GPR81 in diseases of the central nervous system (CNS) such as TBI and cerebral ischemia. In this study we investigated the effects of L-lactate preconditioning on TBI and explored the underlying mechanisms. In this study, the mNSS test revealed that L-lactate preconditioning alleviates the neurological deficit caused by TBI in rats. L-lactate preconditioning significantly increased the expression of GPR81, PSD95, GAP43, BDNF, and MCT2 24 h after TBI in the cortex and hippocampus compared with the sham group. Taken together, these data suggested that L-lactate preconditioning is an effective method with which to recover neurological function after TBI. This reveals the mechanism of L-lactate preconditioning on TBI and provides a potential therapeutic method for TBI in humans.


Asunto(s)
Lesiones Traumáticas del Encéfalo/metabolismo , Ácido Láctico/farmacología , Plasticidad Neuronal/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Receptores Acoplados a Proteínas G/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Masculino , Plasticidad Neuronal/fisiología , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
10.
Angew Chem Int Ed Engl ; 59(3): 1171-1175, 2020 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-31702869

RESUMEN

A simple solvent ligation effect was successfully used to disrupt the growth of a model compound, Fe[(OH)(O3 P(CH2 )2 CO2 H)]⋅H2 O (MIL-37), into an extended 2D structure by replacing water with dimethylformamide (DMF) as the solvent during the synthesis. Owing to the lack of -OH group, which provides the corner-sharing (binding) oxygen atoms for the octahedra, an amorphous and porous structure is formed. When Fe3+ is partially replaced by Ni2+ , the amorphous structure remains and the resultant binary metal catalyst displays excellent photocatalytic oxygen evolution activity with almost 100 % yield achieved under visible light irradiation using [Ru(bpy)3 ]2+ as the photosensitizer. This study opens up new possibilities of using the simple solvent effect to synthesize high surface area metal phosphonates for catalytic and other applications.

11.
ChemSusChem ; 12(9): 2029-2034, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-30088698

RESUMEN

A Pt2+ /Pt0 hybrid nanodot-modified graphitic carbon nitride (CN) photocatalyst (CNV-P) was fabricated for the first time using a chemical reduction method, during which nitrogen vacancies in g-C3 N4 assist to stabilize Pt2+ species. It is elucidated that the coexistence of metallic Pt0 and Pt2+ species in the Pt nanodots loaded on g-C3 N4 results in superior photocatalytic H2 evolution performance with very low Pt loadings. The turnover frequencies (TOFs) are 265.91 and 116.38 h-1 for CNV-P-0.1 (0.1 wt % Pt) and CNV-P-0.5 (0.5 wt % Pt), respectively, which are much higher than for other g-C3 N4 -based photocatalysts with Pt co-catalyst reported previously. The excellent photocatalytic H2 evolution performance is a result of i) metallic Pt0 facilitating the electron transport and separation and Pt2+ species preventing the undesirable H2 backward reaction, ii) the strong interfacial contact between Pt2+ /Pt0 hybrid nanodots and nitrogen vacancies of CNV facilitating the interfacial electron transfer, and iii) the highly dispersed Pt2+ /Pt0 hybrid nanodots exposing more active sites for photocatalytic H2 evolution. Our findings are useful for the design of highly active semiconductor-based photocatalysts with extremely low precious metal content to reduce the catalyst cost while achieving good activity.

12.
Angew Chem Int Ed Engl ; 57(41): 13570-13574, 2018 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-30155982

RESUMEN

Halide perovskite quantum dots (QDs) have great potential in photocatalytic applications if their low charge transportation efficiency and chemical instability can be overcome. To circumvent these obstacles, we anchored CsPbBr3 QDs (CPB) on NHx -rich porous g-C3 N4 nanosheets (PCN) to construct the composite photocatalysts via N-Br chemical bonding. The 20 CPB-PCN (20 wt % of QDs) photocatalyst exhibits good stability and an outstanding yield of 149 µmol h-1 g-1 in acetonitrile/water for photocatalytic reduction of CO2 to CO under visible light irradiation, which is around 15 times higher than that of CsPbBr3 QDs. This study opens up new possibilities of using halide perovskite QDs for photocatalytic application.

13.
Adv Mater ; : e1707582, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29873121

RESUMEN

Crystalline frameworks including primarily metal organic frameworks (MOF) and covalent organic frameworks (COF) have received much attention in the field of heterogeneous catalysts recently. Beyond providing large surface area and spatial confinement, these crystalline frameworks can be designed to either directly act as or influence the catalytic sites at molecular level. This approach offers a unique advantage to gain deeper insights of structure-activity correlations in solid materials, leading to new guiding principles for rational design of advanced solid catalysts for potential important applications related to energy and fine chemical synthesis. In this review, recent key progress achieved in designing MOF- and COF-based molecular solid catalysts and the mechanistic understanding of the catalytic centers and associated reaction pathways are summarized. The state-of-the-art rational design of MOF- and COF-based solid catalysts in this review is grouped into seven different areas: (i) metalated linkers, (ii) metalated moieties anchored on linkers, (iii) organic moieties anchored on linkers, (iv) encapsulated single sites in pores, and (v) metal-mode-based active sites in MOFs. Along with this, some attention is paid to theoretical studies about the reaction mechanisms. Finally, technical challenges and possible solutions in applying these catalysts for practical applications are also presented.

14.
Brain Behav ; 8(3): e00929, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29541541

RESUMEN

Introduction: Social isolation enhances the aggressive behavior of animals, but the detailed mechanism remains unclear. Epigenetic studies have suggested that Htr2c RNA editing is closely related to aggressive behavior. This study aims to obtain a fundamental understanding of how social isolation impacts adenosine deaminase acting on RNA 1 (ADAR1, RNA editing enzyme) and Htr2c RNA editing, leading to aggressive behavior, and explore the effective solutions for the recovery of this behavior. Methods: We evaluated 21-day-old BALB/c mice with and without isolation for aggressive behavior using a resident-intruder test. Immune-reactivity and protein expression of ADAR1 (p110) were measured using immunohistochemistry and Western blotting. Htr2c RNA editing was evaluated using pyrosequencing. In addition, the 5-HT 2C R antagonist SB243213/5-HT 2C R inverse agonist SB206553 was used to treat the isolated mice, and the performance of both treatments on the behavior, ADAR1 (p110) expression, and Htr2c RNA editing in isolated mice was examined. Results: Both the protein expression and immune-reactivity of ADAR1 (p110) in the amygdala decreased, but the percentage of Htr2c RNA editing at A and B sites of amygdala only showed a moderate increase in isolated BALB/c mice with enhanced aggressive behavior compared to the age-matched group-housed BALB/c mice. Additionally, treatment with the 5-HT 2C R antagonist SB243213/5-HT 2C R inverse agonist SB206553 recovered the enhanced aggressive behavior of isolated mice and returned the protein expression and immune-reactivity of ADAR1 (p110) back to the normal level. Moreover, compared to the age-matched isolated mice treated with physiological saline, isolated mice treated with 5-HT 2C R inverse agonist SB206553 showed a lower percentage of Htr2c RNA editing at both A and B sites, and the same result occurred in isolated mice treated with 5-HT 2C R antagonist SB243213 at B site of Htr2c RNA editing. Conclusions: The 5-HT 2C R antagonist SB243213/5-HT 2C R inverse agonist SB206553 recovered increased aggressive behavior of isolated BALB/c mice mediated by ADAR1 (p110) expression and Htr2c RNA editing.


Asunto(s)
Adenosina Desaminasa/genética , Agresión/psicología , Edición de ARN/genética , Receptor de Serotonina 5-HT2C/genética , Agonistas del Receptor de Serotonina 5-HT2/uso terapéutico , Aislamiento Social/psicología , Adenosina Desaminasa/metabolismo , Amígdala del Cerebelo/metabolismo , Animales , Western Blotting , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Receptor de Serotonina 5-HT2C/metabolismo , Agonistas del Receptor de Serotonina 5-HT2/metabolismo
15.
Adv Mater ; 30(5)2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29226560

RESUMEN

In this work, a one-pot solution method for direct synthesis of interconnected ultrafine amorphous NiFe-layered double hydroxide (NiFe-LDH) (<5 nm) and nanocarbon using the molecular precursor of metal and carbon sources is presented for the first time. During the solvothermal synthesis of NiFe-LDH, the organic ligand decomposes and transforms to amorphous carbon with graphitic nanodomains by catalytic effect of Fe. The confined growth of both NiFe-LDH and carbon in one single sheet results in fully integrated amorphous NiFe-LDH/C nanohybrid, allowing the harness of the high intrinsic activity of NiFe-LDH due to (i) amorphous and distorted LDH structure, (ii) enhanced active surface area, and (iii) strong coupling between the active phase and carbon. As such, the resultant NiFe-LDH/C exhibits superior activity and stability. Different from postdeposition or electrostatic self-assembly process for the formation of LDH/C composite, this method offers one new opportunity to fabricate high-performance oxygen evolution reaction and possibly other catalysts.

16.
Dalton Trans ; 46(32): 10650-10656, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28436511

RESUMEN

Photocatalytic hydrogen (H2) evolution from water splitting is attracting enormous interest due to the possibility of converting solar energy into green chemical energy. The construction of highly efficient and stable photocatalysts is of importance and necessary for the development of photocatalytic water splitting technology. In this study, we have developed a self-template synthetic strategy for the preparation of heterostructured nanohybrids composed of ultrasmall CdS and NiSx nanoparticles by using Cd(ii)-Ni(ii)-(4,4'-bipyridine) coordination polymers as the precursor and template. The CdS/NiSx nanohybrids are comprised of integrated CdS and NiSx nanoclusters in a heterostructure which function as highly efficient visible-light-driven H2 evolution photocatalysts. The enhanced photocatalytic performance could be attributed to the formation of hetero-junctions between CdS and NiSx nanoparticles inside the nanohybrids which could effectively improve the separation efficiency of photogenerated electrons and holes, and thus enhance the photocatalytic activity. This work can provide a new insight into the design and fabrication of other heterostructured photocatalysts for solar-driven water splitting or other photocatalytic applications.

17.
Adv Mater ; 29(11)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28102612

RESUMEN

Nickel nanoparticles encapsulated in few-layer nitrogen-doped graphene (Ni@NC) are synthesized by using a Ni-based metal-organic framework as the precursor for high-temperature annealing treatment. The resulting Ni@NC materials exhibit highly efficient and ultrastable electrocatalytic activity toward the hydrogen evolution reaction and the oxygen evolution reaction as well as overall water splitting in alkaline environment.

18.
Anim Sci J ; 88(5): 798-806, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27619417

RESUMEN

Both Kunming (KM) mice and BALB/c mice have been widely used as rodent models to investigate stress-associated mental diseases. However, little is known about the different behaviors of KM mice and BALB/c mice after social isolation, particularly cognitive and aggressive behaviors. In this study, the behaviors of KM and BALB/c mice isolated for 2, 4 and 8 weeks and age-matched controls were evaluated using object recognition, object location and resident-intruder tests. The recovery of behavioral deficits by re-socialization was also examined for the isolated mice in adolescence. Our study showed that isolation for 2, 4 and 8 weeks led to cognitive deficits and increased aggressiveness for both KM and BALB/c mice. An important finding is that re-socialization could completely recover spatial/non-spatial cognitive deficits resulted from social isolation for both KM and BALB/c mice. In addition, age only impacted aggressiveness of KM mice. Moreover, isolation duration showed different impacts on cognitive and aggressive behaviors for both KM and BALB/c mice. Furthermore, BALB/c mice showed weak spatial/non-spatial memory and low aggressiveness when they were at the same age and isolation duration, compared to KM mice. In conclusion, KM mice and BALB/c mice behaved characteristically under physiology and isolation conditions.


Asunto(s)
Agresión , Envejecimiento/psicología , Cognición , Trastornos Mentales/psicología , Aislamiento Social/psicología , Socialización , Animales , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos BALB C , Factores de Tiempo
19.
PeerJ ; 4: e2306, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27602277

RESUMEN

It has been reported that social isolation stress could be a key factor that leads to cognitive deficit for both humans and rodent models. However, detailed mechanisms are not yet clear. ADAR1 (Adenosine deaminase acting on RNA) is an enzyme involved in RNA editing that has a close relation to cognitive function. We have hypothesized that social isolation stress may impact the expression of ADAR1 in the brain of mice with cognitive deficit. To test our hypothesis, we evaluated the cognition ability of mice isolated for different durations (2, 4, and 8 weeks) using object recognition and object location tests; we also measured ADAR1 expression in hippocampus and cortex using immunohistochemistry and western blot. Our study showed that social isolation stress induced spatial and non-spatial cognition deficits of the tested mice. In addition, social isolation significantly increased both the immunoreactivity and protein expression of ADAR1 (p110) in the hippocampus and frontal cortex. Furthermore, re-socialization could not only recover the cognition deficits, but also bring ADAR1 (p110) immunoreactivity of hippocampus and frontal cortex, as well as ADAR1 (p110) protein expression of hippocampus back to the normal level for the isolated mice in adolescence. In conclusion, social isolation stress significantly increases ADAR1 (p110) expression in the hippocampus and frontal cortex of the mice with cognitive deficit. This finding may open a window to better understand the reasons (e.g., epigenetic change) that are responsible for social isolation-induced cognitive deficit and help the development of novel therapies for the resulted diseases.

20.
Nanoscale ; 8(30): 14438-47, 2016 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-27406067

RESUMEN

We report the construction of a highly efficient noble metal free photocatalytic hydrogen (H2) evolution system using CdS quantum dots as the light absorber and metallic MoP as the cocatalyst. MoP can be prepared by a facile temperature programmed reduction method and small clusters of MoP nanoparticles sized 10-30 nm were obtained by probe ultrasonication. The effect of synthesis conditions on the electrocatalytic and photocatalytic H2 evolution activity of MoP was investigated. The highest H2 evolution rate of 1100 µmol h(-1) can be achieved by the optimized system under visible light (λ≥ 420 nm), which is comparable to that when Pt was used as the cocatalyst. A high quantum efficiency of 45% is obtained at 460 nm irradiation.

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