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1.
Int J Cancer ; 155(6): 1033-1044, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38733325

RESUMO

Epidemiological evidence regarding the relationship between coffee and tea consumption and the risk of ovarian cancer (OC) is inconsistent. Therefore, we aimed to quantitatively investigate this topic in a large prospective cohort study. This cohort study included 24,715 individuals recruited from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trials between 1993 and 2001. The data used for our analysis included the latest follow-up information collected up to 2015. Coffee intake of ≥4 cups/day (hazard ratio [HR], 0.586; 95% confidence interval [CI]: 0.356-0.966) or caffeine intake of 458.787 mg/day (HR, 0.607; 95% CI: 0.411-0.895) were associated with the lowest HR of incident OC in the fully adjusted model. Participants who consumed varying amounts of tea did not exhibit a statistically significant reduction in the risk of OC. Our findings suggest that a higher consumption of coffee or caffeine is associated with a reduced risk of OC. However, no statistically significant association was observed between tea consumption and the risk of OC.


Assuntos
Café , Neoplasias Ovarianas , Chá , Humanos , Feminino , Neoplasias Ovarianas/epidemiologia , Estudos Prospectivos , Pessoa de Meia-Idade , Incidência , Idoso , Cafeína/administração & dosagem , Fatores de Risco , Modelos de Riscos Proporcionais
2.
Mol Med ; 30(1): 54, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649802

RESUMO

BACKGROUND: Bleomycin, a potent antitumor agent, is limited in clinical use due to the potential for fatal pulmonary toxicity. The accelerated DNA damage and senescence in alveolar epithelial cells (AECs) is considered a key factor in the development of lung pathology. Understanding the mechanisms for bleomycin-induced lung injury is crucial for mitigating its adverse effects. METHODS: Human lung epithelial (A549) cells were exposed to bleomycin and subsequently assessed for cellular senescence, DNA damage, and double-strand break (DSB) repair. The impact of Rad51 overexpression on DSB repair and senescence in AECs was evaluated in vitro. Additionally, bleomycin was intratracheally administered in C57BL/6 mice to establish a pulmonary fibrosis model. RESULTS: Bleomycin exposure induced dose- and time-dependent accumulation of senescence hallmarks and DNA lesions in AECs. These effects are probably due to the inhibition of Rad51 expression, consequently suppressing homologous recombination (HR) repair. Mechanistic studies revealed that bleomycin-mediated transcriptional inhibition of Rad51 might primarily result from E2F1 depletion. Furthermore, the genetic supplement of Rad51 substantially mitigated bleomycin-mediated effects on DSB repair and senescence in AECs. Notably, decreased Rad51 expression was also observed in the bleomycin-induced mouse pulmonary fibrosis model. CONCLUSIONS: Our works suggest that the inhibition of Rad51 plays a pivotal role in bleomycin-induced AECs senescence and lung injury, offering potential strategies to alleviate the pulmonary toxicity of bleomycin.


Assuntos
Bleomicina , Senescência Celular , Reparo do DNA , Rad51 Recombinase , Bleomicina/efeitos adversos , Rad51 Recombinase/metabolismo , Rad51 Recombinase/genética , Animais , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Humanos , Camundongos , Reparo do DNA/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Células A549 , Dano ao DNA/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Fator de Transcrição E2F1/metabolismo , Fator de Transcrição E2F1/genética , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/efeitos dos fármacos
3.
Int J Med Sci ; 21(8): 1472-1490, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903914

RESUMO

Synuclein family members (Snca, Sncb, and Scng) are expressed in the retina, but their precise locations and roles are poorly understood. We performed an extensive analysis of the single-cell transcriptome in healthy and injured retinas to investigate their expression patterns and roles. We observed the expression of all synuclein family members in retinal ganglion cells (RGCs), which remained consistent across species (human, mouse, and chicken). We unveiled differential expression of Snca across distinct clusters (highly expressed in most), while Sncb and Sncg displayed uniform expression across all clusters. Further, we observed a decreased expression in RGCs following traumatic axonal injury. However, the proportion of α-Syn-positive RGCs in all RGCs and α-Syn-positive intrinsically photosensitive retinal ganglion cells (ipRGCs) in all ipRGCs remained unaltered. Lastly, we identified changes in communication patterns preceding cell death, with particular significance in the pleiotrophin-nucleolin (Ptn-Ncl) and neural cell adhesion molecule signaling pathways, where communication differences were pronounced between cells with varying expression levels of Snca. Our study employs an innovative approach using scRNA-seq to characterize synuclein expression in health retinal cells, specifically focusing on RGC subtypes, advances our knowledge of retinal physiology and pathology.


Assuntos
Células Ganglionares da Retina , alfa-Sinucleína , gama-Sinucleína , Animais , Células Ganglionares da Retina/metabolismo , Humanos , Camundongos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , gama-Sinucleína/genética , gama-Sinucleína/metabolismo , beta-Sinucleína/genética , beta-Sinucleína/metabolismo , Galinhas/genética , Transcriptoma , Análise de Célula Única , Retina/metabolismo , Retina/citologia , Proteínas de Neoplasias
4.
Inorg Chem ; 62(35): 14300-14309, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37595027

RESUMO

The design and development of high-performance electrochemical electrode materials are crucial for energy storage and conversion systems. This work reports a facile preparation of a self-supported Zn/Co-S@Ni(OH)2 array electrode in which a Zn/Co-S nanosheet is derived from a leaf-like zeolitic imidazolate framework (Zn/Co-ZIF-L). The core-shell structure provides multiple benefits such as enhanced electrical conductivity, an abundance of exposed active sites, and strong electronic interactions between Zn/Co-S and ultra-thin Ni(OH)2 nanosheets, facilitating faster charge transfer. Consequently, Zn/Co-S@Ni(OH)2 demonstrates remarkable electrochemical characteristics as an electrode material for supercapacitors with an area capacitance of 12.9 F cm-2 at a current density of 2 mA cm-2 in 2 M KOH. The assembled asymmetric supercapacitor device achieves a high energy density of 0.95 mW h cm-2, while showing excellent longevity with a retention of 90.9% over 5000 cycles. Additionally, the Zn/Co-S@Ni(OH)2 arrays demonstrate significant oxygen evolution reaction activity with an overpotential of 242 mV at 10 mA cm-2 in 1 M KOH and significant stability for more than 100 h. This work provides a valuable approach for synthesizing bifunctional electrode materials for both energy storage and electrocatalysis applications.

5.
Inorg Chem ; 62(49): 20194-20201, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37988673

RESUMO

Layered double hydroxides (LDHs) are some of the most promising precursors for the development of economically stable and efficient electrocatalysts for water splitting. An effective strategy for designing excellent performance electrocatalysts is to assemble core-shell heterostructures with a tunable electronic structure. In this work, three core-shell heterostructure electrocatalysts (NiCo@NiFe-LDH100/150/200) are developed by a simple hydrothermal and subsequent electrodeposition method on Ni foam. Among them, NiCo@NiFe-LDH150/NF exhibits the best oxygen evolution reaction electrocatalytic activity and long-term stability with a low overpotential of 197 mV to deliver a current density of 10 mA cm-2. In addition, an efficient and stable alkaline electrolytic cell with NiCo@NiFe-LDH150/NF both as the cathode and anode achieves a voltage of 1.66 V at a current density of 10 mA cm-2 and realization of ultralong stability at current densities of 20 and 200 mA cm-2 for 200 h. Density functional theory calculations reveal the strong electron interaction at the heterogeneous interface of the NiCo@NiFe-LDH150/NF core-shell structure, which effectively improves the intrinsic electron conductivity and ion diffusion kinetics and makes an important contribution to the electrocatalytic performance of the material. This work provides a new idea for the selection of materials for electrochemical water splitting by the construction of heterojunction interfaces.

6.
Int J Mol Sci ; 24(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37373265

RESUMO

The strictosidine synthase-like (SSL) gene family is a small plant immune-regulated gene family that plays a critical role in plant resistance to biotic/abiotic stresses. To date, very little has been reported on the SSL gene in plants. In this study, a total of thirteen SSLs genes were identified from poplar, and these were classified into four subgroups based on multiple sequence alignment and phylogenetic tree analysis, and members of the same subgroup were found to have similar gene structures and motifs. The results of the collinearity analysis showed that poplar SSLs had more collinear genes in the woody plants Salix purpurea and Eucalyptus grandis. The promoter analysis revealed that the promoter region of PtrSSLs contains a large number of biotic/abiotic stress response elements. Subsequently, we examined the expression patterns of PtrSSLs following drought, salt, and leaf blight stress, using RT-qPCR to validate the response of PtrSSLs to biotic/abiotic stresses. In addition, the prediction of transcription factor (TF) regulatory networks identified several TFs, such as ATMYB46, ATMYB15, AGL20, STOP1, ATWRKY65, and so on, that may be induced in the expression of PtrSSLs in response to adversity stress. In conclusion, this study provides a solid basis for a functional analysis of the SSL gene family in response to biotic/abiotic stresses in poplar.


Assuntos
Proteínas de Plantas , Populus , Proteínas de Plantas/metabolismo , Filogenia , Perfilação da Expressão Gênica/métodos , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Populus/metabolismo
7.
Inorg Chem ; 61(10): 4283-4291, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35238556

RESUMO

The amino-functionalized bimetal NH2-NiCo-MOF nanosheet array is first fabricated on Ni foam substrates and then controllably transformed into oxygen vacancy bimetal oxide arrays by simply thermal annealing in air. This NiCo-based oxide array (NixCo3-xO4/NF) achieves high capacitance (2484 F g-1 at 1 A g-1), excellent rate performance (91.4%), and long cycling life when assessed as promising electrode material for supercapacitors. Notably, the existing oxygen vacancy in NixCo3-xO4 promotes the electrochemical performance of NixCo3-xO4/NF due to the enhancement of electrical conductivity and capture capability for OH-. In addition, the assembled asymmetric supercapacitor (ASC) device exhibits an excellent energy density of 39.3 W h kg-1 at a power density of 800.2 W kg-1, which still remains 32.2 W h kg-1 even at a high power density of 7994.5 W kg-1. Furthermore, a light-emitting diode can be lightened for more than 6 min, demonstrating a great potential for practical application of ASC devices. This work knocks on the door of a feasible strategy for designing and synthesizing 2D metal oxide nanosheet arrays with excellent electrochemical properties.

8.
Inorg Chem ; 61(9): 3832-3842, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35192761

RESUMO

Ultrathin two-dimensional metal-organic frameworks (MOFs) have convincing performances in energy storage, which can be put down to their accessible active sites with rapid charge transfer. Herein, NiCo-layered double hydroxide (LDH) nanosheet arrays are used as self-sacrificial templates to in situ fabricate ultrathin NiCo-MOF nanosheet arrays on Ni foam (NS/NF) by using organic ligands without adding metal sources. Two ultrathin MOF nanosheets with different ligands, terephthalate (BDC) and 2-aminoterephthalate (NH2-BDC), are synthesized, characterized, and discussed in detail. Specifically, NiCo-NH2-BDC-MOF NS/NF exhibits the best electrochemical performance as a battery-type electrode for supercapacitors, achieves an areal capacitance of 12.13 F cm-2 at a current density of 2 mA cm-2, and retains the original capacitance of 73.08 % after 5000 cycles at a current density of 50 mA cm-2. Furthermore, when NiCo-NH2-BDC-MOF NS/NF is assembled with activated carbon (AC) to form an asymmetric supercapacitor (ASC), an energy density of 0.81 mWh cm-2 can be provided at a power density of 1.60 mW cm-2. These results offer an effective and controllable synthetic strategy to in situ prepare ultrathin MOF nanosheet arrays with different ligands and metal ions from LDH precursors.

9.
Inorg Chem ; 55(2): 549-51, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26713454

RESUMO

A multifunctional metal-organic framework, NBU-3, has been explored as a 2D three-connected network based on a naphthalenediimide-based ligand. The NBU-3 crystals display photochromic properties, and NBU-3 thin films on FTO substrates exhibit electrochromic properties. NBU-3 is the first example of MOF materials containing both photochromic and electrochromic properties, which can be desirable for thin film devices.

10.
Can J Physiol Pharmacol ; 92(10): 797-803, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25203284

RESUMO

This study aimed to study the combined effect of rosuvastatin and probucol on atherosclerosis (AS) in rats. In total, 95 male Wistar rats were divided into 5 groups: 25 in the control group (A), 25 in the model group (B), 15 in the rosuvastatin group (C), 15 in the probucol group (D), and 15 in the rosuvastatin combined probucol group (E). A high-lipid diet and vitamin D3 were administered to establish AS rat model. Groups C, D, and E received corresponding drugs. Blood lipids, oxidized low-density lipoprotein (OX-LDL), malonaldehyde (MDA), superoxide dismutase (SOD), adiponectin (APN), and vascular endothelial cadherin (VE-cadherin) were measured. Platelet endothelial cell adhesion molecule-1 (PECAM-1) was detected by immune histochemistry. In groups B-E, AS rat models were successfully constructed. In groups C-E, blood lipids, OX-LDL, VE-cadherin, MDA, PECAM-1, and intimal thickness were decreased (p < 0.01), while SOD and APN were increased (p < 0.05), compared with that in group B. Furthermore, group E had lower levels of OX-LDL, MDA, and PECAM-1 but higher levels of SOD and APN and attenuated intimal thickening compared with groups C or D (p < 0.05). Administering rosuvastatin and probucol could attenuate AS lesions through modulation of oxidative stress, PECAM-1, and APN. Both drugs might help slow the progression of AS.


Assuntos
Antioxidantes/uso terapêutico , Aterosclerose/tratamento farmacológico , Fluorbenzenos/uso terapêutico , Probucol/uso terapêutico , Pirimidinas/uso terapêutico , Sulfonamidas/uso terapêutico , Animais , Aterosclerose/metabolismo , Aterosclerose/patologia , Quimioterapia Combinada , Lipídeos/sangue , Masculino , Estresse Oxidativo/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Ratos Wistar , Rosuvastatina Cálcica , Túnica Íntima/efeitos dos fármacos , Túnica Íntima/patologia
11.
J Vis Exp ; (207)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856213

RESUMO

Volume electron microscopy (Volume EM) has emerged as a powerful tool for visualizing the 3D structure of cells and tissues with nanometer-level precision. Within the retina, various types of neurons establish synaptic connections in the inner and outer plexiform layers. While conventional EM techniques have yielded valuable insights into retinal subcellular organelles, their limitation lies in providing 2D image data, which can hinder accurate measurements. For instance, quantifying the size of three distinct synaptic vesicle pools, crucial for synaptic transmission, is challenging in 2D. Volume EM offers a solution by providing large-scale, high-resolution 3D data. It is worth noting that sample preparation is a critical step in Volume EM, significantly impacting image clarity and contrast. In this context, we outline a sample preparation protocol for the 3D reconstruction of photoreceptor axon terminals in the retina. This protocol includes three key steps: retina dissection and fixation, sample embedding processes, and selection of the area of interest.


Assuntos
Retina , Retina/ultraestrutura , Animais , Microscopia Eletrônica/métodos , Imageamento Tridimensional/métodos , Camundongos , Microscopia Eletrônica de Volume
12.
Dalton Trans ; 53(9): 4067-4079, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38312038

RESUMO

Transition metal sulfides are promising electrode materials for supercapacitors due to their excellent electrochemical performance and high conductivity. Unfortunately, the low rate performance and poor cycling stability limited their progress towards commercial applications. Herein, the core-shell structure of MoO42--intercalated LDHs coated on Co9S8 nanotubes was rationally designed and prepared to improve their electrochemical performance and cycling stability by adjusting the composition of LDHs. Compared to NiMo-LDH@Co9S8 and CoMo-LDH@Co9S8, the optimized NiCoMo-LDH@Co9S8 electrode exhibits excellent areal specific capacitance (11 F cm-2 at 3 mA cm-2) and excellent cycling stability (94.4% after 5000 cycles). In addition, asymmetric supercapacitor devices were assembled with NiCoMo-LDH@Co9S8 and activated carbon (AC), which delivered a high energy density of 0.94 mWh cm-2, at a power density of 1.70 mW cm-2, and good cycling stability (89.4% after 5000 cycles). These results indicate that the introduction of MoO42- can enhance the synergistic effect of multiple metals and the synthesized NiCoMo-LDH@Co9S8 core-shell composite has great potential in the development of high-performance electrode materials for supercapacitors.

13.
Eur J Surg Oncol ; 50(3): 107975, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38295548

RESUMO

BACKGROUND: Ovarian clear cell carcinoma (OCCC) is a rare pathological type of ovarian cancer with a poor prognosis, and lymphadenectomy is controversial in patients with OCCC. The objective of this study was to evaluate the impact of lymphadenectomy on the prognosis of patients with OCCC. METHODS: In this retrospective study, we collected data from the Surveillance, Epidemiology and End Results (SEER) database and institutional registries in China. The SEER cohort included 1777 women diagnosed with OCCC between 2010 and 2019, while the Chinese cohort included 199 women diagnosed between April 2004 and April 2021. Recurrence-free survival (RFS) and overall survival (OS) were studied using Kaplan-Meier curve and Cox regression analysis. We also employed propensity score matching (PSM) to adjust for baseline imbalances between the lymphadenectomy group and the no-lymphadenectomy group. RESULTS: Multivariate cox regression analysis showed that lymphadenectomy was not associated with better overall survival (OS) in either early (hazard ratio [HR] 0.84[0.50-1.43], p = 0.528) or advanced (HR 0.78[0.50-1.21], p = 0.270) patients in the SEER cohort after PSM. Additionally, in the Kaplan-Meier curve analysis, lymphadenectomy did not significantly improve OS in both early (p = 0.28) and advanced (p = 0.49) patients in the SEER cohort after PSM. Similarly, in the Chinese cohort, lymphadenectomy had no significant effect on OS (early p = 0.22; advanced p = 0.61) or RFS (early p = 0.18; advanced p = 0.83) in both early and advanced patients. CONCLUSION: In completely homogeneous groups, lymphadenectomy in women diagnosed with OCCC had no effect on either recurrence-free survival or overall survival compared to patients without lymphadenectomy.


Assuntos
Adenocarcinoma de Células Claras , Neoplasias Ovarianas , Humanos , Feminino , Estudos Retrospectivos , Estadiamento de Neoplasias , Prognóstico , Sistema de Registros , Excisão de Linfonodo , Adenocarcinoma de Células Claras/cirurgia , Adenocarcinoma de Células Claras/metabolismo
14.
Brain Struct Funct ; 229(5): 1279-1298, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703218

RESUMO

ß-synuclein, a member of the synuclein family, is frequently co-expressed with α-synuclein in the neural system, where it serves to inhibit abnormal aggregation of α-synuclein in neurodegenerative diseases. Beyond its role in pathological conditions, ß-synuclein plays various functions independently of α-synuclein. In our investigation, we discovered a broader expression of ß-synuclein in the mouse retina compared to α-synuclein. This widespread pattern implies its potential significance in the retina. Through detailed examination via light- and electron-microscopic immunocytochemistry, we identified ß-synuclein expression from the inner segment (IS) and outer segment (OS) of photoreceptor cells to the ganglion cell layer (GCL). Our findings unveiled unique features, including ß-synuclein immunoreactive IS and OS of cones, higher expression in cone pedicles than in rod spherules, absence in horizontal cells, limited expression in cone bipolar dendrites and somas, higher expression in cone bipolar terminals, presence in most amacrine cells, and expression in almost majority of somas in GCL with an absence in intrinsically photosensitive retinal ganglion cell (ipRGCs) processes. Notably, all cholinergic amacrine cells express high ß- but not α-synuclein, while dopaminergic amacrine cells express α-synuclein exclusively. These distinctive expression patterns offer valuable insights for further exploration into the functions of ß-synuclein and its potential role in synuclein pathology within the retina.


Assuntos
Camundongos Endogâmicos C57BL , Retina , Células Ganglionares da Retina , alfa-Sinucleína , beta-Sinucleína , Animais , Masculino , Camundongos , alfa-Sinucleína/metabolismo , Células Amácrinas/metabolismo , beta-Sinucleína/metabolismo , Retina/metabolismo , Células Bipolares da Retina/metabolismo , Células Ganglionares da Retina/metabolismo
15.
Inorg Chem ; 52(4): 1667-9, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-23374148

RESUMO

A doubly interpenetrated metal-organic framework, [Zn(3)(TATB)(2)(H(2)O)(2)](n) (2), with chiral (10,3)-a topology, has been synthesized from an achiral, trigonal-planar ligand, 4,4',4″-s-triazine-2,4,6-triyltribenzoate (TATB). The large chiral channels in 2 act as scaffolds for the inclusion of N,N-dimethylaniline (DMA) molecules by donor-acceptor interactions. The resulting host-guest composite, DMA@2, shows desirably intense luminescence, which originated from photoinduced charge-transfer interactions in excited states.


Assuntos
Compostos Organometálicos/química , Zinco/química , Cristalografia por Raios X , Luminescência , Modelos Moleculares , Compostos Organometálicos/síntese química
16.
Dalton Trans ; 52(36): 12978-12987, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37650574

RESUMO

Layered double hydroxides (LDHs) and metal sulfides (MSs) have been widely used as promising electrode materials for supercapacitors, and the rational architectural design of MS/LDH heterogeneous structures is critical to optimize large energy storage. Herein, a precisely designed hollow Co9S8 nanotubes@CoNi-LDH nanosheet heterostructure on Ni foam, facilely prepared by an ingenious in situ strategy in this Co9S8 nanoarray was first used as the self-sacrificing template and metal source to in situ synthesize Co-ZIF-67 polyhedron to form the Co9S8@ZIF-67 heterostructure, and then Co9S8@ZIF-67 was in situ etched successfully using Ni2+ ions to form the final Co9S8@CoNi-LDH/NF core-shell nanoarray. This in situ synthetic strategy to fabricate the heterostructure is conducive to boosting the structural stability, modifying the electric structure and regulating the interfacial charge transfer. Due to the synergistic effect and tight heterogeneous interface, Co9S8@CoNi-LDH/NF displayed an outstanding capacitance of 9.65 F cm-2 at a current density of 2 mA cm-2 and excellent capacitance retention rate of 91.7% after 5000 cycles. In addition, the ASC device assembled with AC has an extremely high energy density of 1.0 mW h cm-2 at 2 mA cm-2 and maintains 96.9% capacitance retention after 5000 cycles. This work provides a skillful strategy for the precise design and in situ synthesis of MS/LDH heterostructures with fascinating features for electrochemical energy storage applications.

17.
Dalton Trans ; 52(27): 9346-9355, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37351852

RESUMO

Binary transition metal sulfides are considered to be a promising material for supercapacitors, possessing richer electrochemically active sites and superior electrochemical performance. Metal-organic frameworks (MOFs) are often used as self-sacrificing templates in the preparation of metal sulfides. Usually, direct sulfidation of MOFs tends to cause collapse of the morphological structure and blockage of the ion transport channels, so that the morphology of the original MOF template can be well preserved by using pyrolysis followed by S2- ion exchange. In this paper, we first prepared NiCo-MOF-74 on nickel foam by an in situ transformation method from layered double hydroxides (LDHs) through a ligand exchange reaction. Then, CoNi2S4 was synthesized in two steps involving the pyrolysis of NiCo-MOF-74 and a subsequent S2- ion exchange reaction. Compared with direct sulfidation, this synthetic strategy can well maintain the rod-like morphology of MOF-74 arrays and prevent structural collapse. The surface of CoNi2S4 has a fine nanosheet structure, which exposes more active sites and shows a high specific capacitance of 7.50 F cm-2 at 2 mA cm-2 and an excellent Coulomb efficiency (96.32%). In addition, the hybrid supercapacitor assembled with activated carbon shows a high energy density of 0.64 mW h cm-2 at a power density of 1.64 mW cm-2 and a high capacitance retention of 88.39% after 5000 cycles. These results indicate that rod-shaped CoNi2S4 can be controllably prepared from MOF-74 involving an exchange reaction and has promising application in high-performance supercapacitors.

18.
Dalton Trans ; 52(36): 12668-12676, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37646195

RESUMO

Designing highly-efficient, cost-effective, and stable electrocatalysts for water splitting is essential to producing green hydrogen. In this work, a nanoflower quaternary heterostructured Ni(NO3)2(OH)4/Ni(OH)2/Ni3S2/NiFe-LDH electrocatalyst is successfully synthesized by two-step hydrothermal reactions. The sulfur in the electrocatalyst induces higher valence state metal atoms as active sites to accelerate the formation of O2. As expected, benefiting from the unique structural features and solid electronic interactions, Ni(NO3)2(OH)4/Ni(OH)2/Ni3S2/NiFe-LDH exhibits remarkable oxygen evolution reaction performance with a low overpotential of 223 mV at a current density of 100 mA cm-2, a slight Tafel slope of 65.4 mV dec-1, and outstanding stability in alkaline media. Attractively, using Ni(NO3)2(OH)4/Ni(OH)2/Ni3S2/NiFe-LDH as both a cathode and an anode, the alkaline electrolyzer delivers a current density of 10 mA cm-2 only at a cell voltage of 1.67 V, accompanied by superior durability. This work provides a facile method for the rational design of high-performance quaternary electrocatalysts.

19.
Dalton Trans ; 52(29): 10089-10098, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37424430

RESUMO

Metal-organic frameworks (MOFs) have been extensively applied in supercapacitors. Unfortunately, metal active sites in MOFs are commonly blocked and saturated by organic ligands, leading to insufficient positions available for the electrochemical reaction. To address this issue, we develop a novel strategy to design and prepare a series of hollow metal sulfide/MOF heterostructures, which simultaneously alleviate the large volume expansion, avoid slow kinetics of metal sulfides and expose more electrochemically active sites of the MOF. Consequently, the optimized Co9S8/Co-BDC MOF heterostructure presents outstanding electrochemical performance with a high areal specific capacitance of 15.84 F cm-2 at 2 mA cm-2 and a capacitance retention rate of 87.5% after 5000 charge-discharge cycles. The asymmetric supercapacitors based on the heterostructure deliver a high energy density of 0.87 mW h cm-2 and a power density of 19.84 mW cm-2, as well as long cycling stability. This study provides a new strategy for the rational design and in situ synthesis of metal sulfide/MOF heterostructures for electrochemical applications.

20.
Brain Struct Funct ; 228(7): 1703-1724, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37481742

RESUMO

Substance P (SP), a neuroprotective peptidergic neurotransmitter, is known to have immunoreactivity (IR) localized to amacrine and/or ganglion cells in a variety of species' retinas, but it has not yet been studied in the mouse retina. Thus, we investigated the distribution and synaptic organization of SP-IR by confocal and electron microscopy immunocytochemistry in the mouse retina. SP-IR was distributed in the inner nuclear layer (INL), inner plexiform layer (IPL), and ganglion cell layer (GCL). Most of the SP-IR somas belonged to amacrine cells (2.5% of all) in the INL and their processes stratified into the S1, S3, and S5 layers of the IPL, with the most intense band in the S5 layer. Some SP-IR somas can also be observed in the GCL, which were identified as displaced amacrine cells (82%, 1269/1550) and ganglion cells (18%, 281/1550) by antibodies against AP2α and RBPMS, respectively. Such SP-IR ganglion cells (1.2% of all RGCs) can be further divided into 3 subgroups expressing SP/α-Synuclein (α-Syn), SP/GAD67, and/or SP/GAD67/α-Syn. Possible physiological and pathological roles of these ganglion cells are discussed. Further, electron microscopy evidence demonstrates that SP-IR amacrine cells receive major inputs from other SP-IR amacrine cell processes (146/242 inputs) and output mostly to SP-negative amacrine cell processes (291/673 outputs), suggesting series inhibition among amacrine cells. These results reveal for the first time an explicit distribution, novel ganglion cell features, and synaptic organization of SP-IR in the mouse retina, which is important for the future use of mouse models to study the roles of SP in healthy and diseased (including Parkinson's disease) retinal states.


Assuntos
Retina , Substância P , Animais , Camundongos , Substância P/análise , Retina/química , Células Amácrinas , Microscopia Eletrônica , Neurotransmissores
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