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1.
J Am Chem Soc ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38991189

RESUMEN

The electrochemical reduction reaction of carbon dioxide (CO2RR) into valuable products offers notable economic benefits and contributes to environmental sustainability. However, precisely controlling the reaction pathways and selectively converting key intermediates pose considerable challenges. In this study, our theoretical calculations reveal that the active sites with different states of copper atoms (1-3-5-7-9) play a pivotal role in the adsorption behavior of the *CHO critical intermediate. This behavior dictates the subsequent hydrogenation and coupling steps, ultimately influencing the formation of the desired products. Consequently, we designed two model electrocatalysts comprising Cu single atoms and particles supported on CeO2. This design enables controlled *CHO intermediate transformation through either hydrogenation with *H or coupling with *CO, leading to a highly selective CO2RR. Notably, our selective control strategy tunes the Faradaic efficiency from 61.1% for ethylene (C2H4) to 61.2% for methane (CH4). Additionally, the catalyst demonstrated a high current density and remarkable stability, exceeding 500 h of operation. This work not only provides efficient catalysts for selective CO2RR but also offers valuable insights into tailoring surface chemistry and designing catalysts for precise control over catalytic processes to achieve targeted product generation in CO2RR technology.

2.
J Am Chem Soc ; 146(22): 15356-15365, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38773696

RESUMEN

Electrosynthesis has emerged as an enticing solution for hydrogen peroxide (H2O2) production. However, efficient H2O2 generation encounters challenges related to the robust gas-liquid-solid interface within electrochemical reactors. In this work, we introduce an effective hydrophobic coating modified by iron (Fe) sites to optimize the reaction microenvironment. This modification aims to mitigate radical corrosion through Fe(II)/Fe(III) redox chemistry, reinforcing the reaction microenvironment at the three-phase interface. Consequently, we achieved a remarkable yield of up to 336.1 mmol h-1 with sustained catalyst operation for an extensive duration of 230 h at 200 mA cm-2 without causing damage to the reaction interface. Additionally, the Faradaic efficiency of H2O2 exceeded 90% across a broad range of test current densities. This surface redox chemistry approach for manipulating the reaction microenvironment not only advances long-term H2O2 electrosynthesis but also holds promise for other gas-starvation electrochemical reactions.

3.
BMJ ; 384: e078581, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443074

RESUMEN

OBJECTIVE: To evaluate the diagnostic accuracy and safety of using magnetically guided capsule endoscopy with a detachable string (ds-MCE) for detecting and grading oesophagogastric varices in adults with cirrhosis. DESIGN: Prospective multicentre diagnostic accuracy study. SETTING: 14 medical centres in China. PARTICIPANTS: 607 adults (>18 years) with cirrhosis recruited between 7 January 2021 and 25 August 2022. Participants underwent ds-MCE (index test), followed by oesophagogastroduodenoscopy (OGD, reference test) within 48 hours. The participants were divided into development and validation cohorts in a ratio of 2:1. MAIN OUTCOME MEASURES: The primary outcomes were the sensitivity and specificity of ds-MCE in detecting oesophagogastric varices compared with OGD. Secondary outcomes included the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices and the diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices. RESULTS: ds-MCE and OGD examinations were completed in 582 (95.9%) of the 607 participants. Using OGD as the reference standard, ds-MCE had a sensitivity of 97.5% (95% confidence interval 95.5% to 98.7%) and specificity of 97.8% (94.4% to 99.1%) for detecting oesophagogastric varices (both P<0.001 compared with a prespecified 85% threshold). When using the optimal 18% threshold for luminal circumference of the oesophagus derived from the development cohort (n=393), the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices in the validation cohort (n=189) were 95.8% (89.7% to 98.4%) and 94.7% (88.2% to 97.7%), respectively. The diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices was 96.3% (92.6% to 98.2%), 96.9% (95.2% to 98.0%), and 96.7% (95.0% to 97.9%), respectively. Two serious adverse events occurred with OGD but none with ds-MCE. CONCLUSION: The findings of this study suggest that ds-MCE is a highly accurate and safe diagnostic tool for detecting and grading oesophagogastric varices and is a promising alternative to OGD for screening and surveillance of oesophagogastric varices in patients with cirrhosis. TRIAL REGISTRATION: ClinicalTrials.gov NCT03748563.


Asunto(s)
Endoscopía Capsular , Várices Esofágicas y Gástricas , Várices , Adulto , Humanos , Várices Esofágicas y Gástricas/diagnóstico , Várices Esofágicas y Gástricas/etiología , Cirrosis Hepática/complicaciones , Estudios Prospectivos
5.
Angew Chem Int Ed Engl ; 63(16): e202319936, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38372428

RESUMEN

Revealing the dynamic reconstruction process and tailoring advanced copper (Cu) catalysts is of paramount significance for promoting the conversion of CO2 into ethylene (C2H4), paving the way for carbon neutralization and facilitating renewable energy storage. In this study, we initially employed density functional theory (DFT) and molecular dynamics (MD) simulations to elucidate the restructuring behavior of a catalyst under electrochemical conditions and delineated its restructuring patterns. Leveraging insights into this restructuring behavior, we devised an efficient, low-coordination copper-based catalyst. The resulting synthesized catalyst demonstrated an impressive Faradaic efficiency (FE) exceeding 70 % for ethylene generation at a current density of 800 mA cm-2. Furthermore, it showed robust stability, maintaining consistent performance for 230 hours at a cell voltage of 3.5 V in a full-cell system. Our research not only deepens the understanding of the active sites involved in designing efficient carbon dioxide reduction reaction (CO2RR) catalysts but also advances CO2 electrolysis technologies for industrial application.

6.
Nature ; 626(7997): 86-91, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38297172

RESUMEN

Electrolysis that reduces carbon dioxide (CO2) to useful chemicals can, in principle, contribute to a more sustainable and carbon-neutral future1-6. However, it remains challenging to develop this into a robust process because efficient conversion typically requires alkaline conditions in which CO2 precipitates as carbonate, and this limits carbon utilization and the stability of the system7-12. Strategies such as physical washing, pulsed operation and the use of dipolar membranes can partially alleviate these problems but do not fully resolve them11,13-15. CO2 electrolysis in acid electrolyte, where carbonate does not form, has therefore been explored as an ultimately more workable solution16-18. Herein we develop a proton-exchange membrane system that reduces CO2 to formic acid at a catalyst that is derived from waste lead-acid batteries and in which a lattice carbon activation mechanism contributes. When coupling CO2 reduction with hydrogen oxidation, formic acid is produced with over 93% Faradaic efficiency. The system is compatible with start-up/shut-down processes, achieves nearly 91% single-pass conversion efficiency for CO2 at a current density of 600 mA cm-2 and cell voltage of 2.2 V and is shown to operate continuously for more than 5,200 h. We expect that this exceptional performance, enabled by the use of a robust and efficient catalyst, stable three-phase interface and durable membrane, will help advance the development of carbon-neutral technologies.

7.
Dalton Trans ; 53(7): 2957-2963, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38247311

RESUMEN

The energy-saving separation of CO2/N2 and CH4/N2 in the energy industry facilitates the reduction of greenhouse gas emissions and replenishes energy resources, but is a challenging separation process. The trade-off between adsorption capacity and selectivity of the adsorbents is one of the key bottlenecks in adsorption separation technologies' large-scale application in the above separation task. Herein, we introduced a series of fluoroborate or fluorosilicate salts (Cu(BF4)2, Zn(BF4)2 and ZnSiF6) into the open coordination nitrogen sites of aluminum-based metal-organic frameworks (MOF-253) to create multiple binding sites to simultaneously enhance the adsorption capacity and selectivity for the target gas. By the synergistic adsorption effect of metal ions (Cu2+ or Zn2+) and fluorinated anions (BF4- or (SiF6)2-), the single-component adsorption capacity and selectivity of salt-modified MOF-253 (MOF-253@Cu(BF4)2, MOF-253@Zn(BF4)2 and MOF-253@ZnSiF6) for CO2 and CH4 were effectively improved when compared to pristine MOF-253 at 298 K and 1 bar. In addition, the salt-modified MOF-253 has a moderate adsorption heat (<30 kJ mol-1) which could be rapidly regenerated at low energy by evacuation desorption. As confirmed by the ambient breakthrough experiments of MOF-253 and MOF-253@ZnSiF6, the real separation performance for both CO2/N2 (1/4) and CH4/N2 (1/4) was obviously improved. This work provides a feasible post-modification strategy on uncoordinated sites of the framework to improve adsorption separation performance and promote the development of ideal adsorbents with a view to realizing their application in the energy industry.

8.
Micromachines (Basel) ; 14(12)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38138384

RESUMEN

This paper introduces a new finding regarding single event upsets (SEUs) in configuration memory, and their potential impact on enhancing the performance of deep neural networks (DNNs) on the multiprocessor system on chip (MPSoC) platform. Traditionally, SEUs are considered to have negative effects on electronic systems or designs, but the current study demonstrates that they can also have positive contributions to the DNN on the MPSoC. The assertion that SEUs can have positive contributions to electronic system design was supported by conducting fault injections through dynamic reconfiguration on DNNs implemented on a 16nm FinFET technology Zynq UltraScale+ MPSoC. The results of the current study were highly significant, indicating that an SEU in configuration memory could result in an impressive 8.72% enhancement in DNN recognition on the MPSoC. One possible cause is that SEU in the configuration memory leads to slight changes in weight or bias values, resulting in improved activation levels of neurons and enhanced final recognition accuracy. This discovery offers a flexible and effective solution for boosting DNN performance on the MPSoC platform.

9.
Dalton Trans ; 52(23): 7975-7981, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37222531

RESUMEN

The efficient separation of CO2 from CH4 and N2 is essential for the upgrading of biogas and reducing carbon emissions in flue gas, but is challenging in the energy industry. Developing ultra-stable adsorbents with high CO2 adsorption performance in adsorption separation technology is deemed an effective solution for the separation of CO2/CH4 and CO2/N2. Herein, we report an ultra-stable yttrium-based microporous metal-organic framework (Y-bptc) used for the efficient separation of CO2/CH4 and CO2/N2. The single-component equilibrium adsorption capacity of CO2 reached 55.1 cm3 g-1 at 1 bar and 298 K, while the adsorption capacity of CH4 and N2 was almost negligible and thus resulted in a high adsorption ratio for CO2/CH4 (45.5) and CO2/N2 (18.1). GCMC simulations revealed that the µ3-OH- functional groups distributed in the pore cage of Y-bptc provide stronger adsorption sites for CO2via hydrogen-bonding interactions. The relatively lower heat of adsorption of CO2 (24 kJ mol-1) further reduces the desorption regeneration energy consumption. Dynamic breakthrough experiments using Y-bptc for the separation of CO2/CH4 (1/1) and CO2/N2 (1/4) mixtures could obtain high purity (>99%) CH4 and N2, and the CO2 dynamic adsorption capacities reached 52 and 31 cm3 g-1, respectively. More importantly, the structure of Y-bptc remained intact under hydrothermal conditions. The high adsorption ratio, low heat of adsorption, great dynamic separation performance, and ultra-stable structure of Y-bptc make it one of the candidate adsorbents suitable for the separation of CO2/CH4 and CO2/N2 in real-world applications.

10.
Hepatol Commun ; 7(5)2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37141513

RESUMEN

BACKGROUND: Endoscopy plays an important role in the management of acute variceal bleeding (AVB) in patients with cirrhosis. This study aimed at determining the optimal endoscopy timing for cirrhotic AVB. METHODS: Patients with cirrhosis with AVB across 34 university hospitals in 30 cities from February 2013 to May 2020 who underwent endoscopy within 24 hours were included in this study. Patients were divided into an urgent endoscopy group (endoscopy <6 h after admission) and an early endoscopy group (endoscopy 6-24 h after admission). Multivariable analysis was performed to identify risk factors for treatment failure. Primary outcome was the incidence of 5-day treatment failure. Secondary outcomes included in-hospital mortality, need for intensive care unit, and length of hospital stay. A propensity score matching analysis was performed. In addition, we performed an analysis, in which we compared the 5-day treatment failure incidence and the in-hospital mortality among patients with endoscopy performed at <12 hours and 12-24 hours. RESULTS: A total of 3319 patients were enrolled: 2383 in the urgent endoscopy group and 936 in the early endoscopy group. After propensity score matching, on multivariable analysis, Child-Pugh class was identified as an independent risk factor for 5-day treatment failure (HR, 1.61; 95% CI: 1.09-2.37). The incidence of 5-day treatment failure was 3.0% in the urgent endoscopy group and 2.9% in the early group ( p = 0.90). The in-hospital mortality was 1.9% in the urgent endoscopy group and 1.2% in the early endoscopy group ( p = 0.26). The incidence of need for intensive care unit was 18.2% in the urgent endoscopy group and 21.4% in the early endoscopy group ( p = 0.11). The mean length of hospital stay was 17.9 days in the urgent endoscopy group and 12.9 days in the early endoscopy group ( p < 0.05). The incidence of 5-day treatment failure in the <12-hour group was 2.3% and 2.2% in the 12-24 hours group ( p = 0.85). The in-hospital mortality was 2.2% in the <12-hour group and 0.5% in the 12-24 hours group ( p < 0.05). CONCLUSIONS: The data suggest that performance of endoscopy within 6-12 or within 24 hours of presentation among patients with cirrhosis with AVB led to similar treatment failure outcomes.


Asunto(s)
Várices Esofágicas y Gástricas , Hemorragia Gastrointestinal , Humanos , Estudios de Cohortes , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/complicaciones , Estudios Retrospectivos , Cirrosis Hepática/complicaciones , Endoscopía Gastrointestinal
11.
Nat Commun ; 14(1): 69, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36604444

RESUMEN

Sweat sensors play a significant role in personalized healthcare by dynamically monitoring biochemical markers to detect individual physiological status. The specific response to the target biomolecules usually depends on natural oxidase, but it is susceptible to external interference. In this work, we report tryptophan- and histidine-treated copper metal-organic frameworks (Cu-MOFs). This amino-functionalized copper-organic framework shows highly selective activity for ascorbate oxidation and can serve as an efficient ascorbate oxidase-mimicking material in sensitive sweat sensors. Experiments and calculation results elucidate that the introduced tryptophan/histidine fundamentally regulates the adsorption behaviors of biomolecules, enabling ascorbate to be selectively captured from complex sweat and further efficiently electrooxidized. This work provides not only a paradigm for specifically sweat sensing but also a significant understanding of natural oxidase-inspired MOF nanoenzymes for sensing technologies and beyond.


Asunto(s)
Oxidorreductasas , Sudor , Sudor/química , Cobre/química , Histidina , Triptófano
12.
Small ; 19(15): e2207474, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36604992

RESUMEN

Developing bifunctional catalysts for oxygen electrochemical reactions is essential for high-performance electrochemical energy devices. Here, a Mott-Schottky heterojunction composed of porous cobalt-nitrogen-carbon (Co-N-C) polyhedra containing abundant metal-phosphides for reversible oxygen electrocatalysis is reported. As a demonstration, this catalyst shows excellent activity in the oxygen electrocatalysis and thus delivers outstanding performance in rechargeable zinc-air batteries (ZABs). The built-in electric field in the Mott-Schottky heterojunction can promote electron transfer in oxygen electrocatalysis. More importantly, an appropriate d-band center of the heterojunction catalyst also endows oxygen intermediates with a balanced adsorption/desorption capability, thus enhancing oxygen electrocatalysis and consequently improving the performance of ZABs. The work demonstrates an important design principle for preparing efficient multifunctional catalysts in energy conversion technologies.

13.
Angew Chem Int Ed Engl ; 62(12): e202218621, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36658098

RESUMEN

Solid-state lithium batteries are promising and safe energy storage devices for mobile electronics and electric vehicles. In this work, we report a facile in situ polymerization of 1,3-dioxolane electrolytes to fabricate integrated solid-state lithium batteries. The in situ polymerization and formation of solid-state dioxolane electrolytes on interconnected carbon nanotubes (CNTs) and active materials is the key to realizing a high-performance battery with excellent interfacial contact among CNTs, active materials and electrolytes. Therefore, the electrodes could be tightly integrated into batteries through the CNTs and electrolyte. Electrons/ions enable full access to active materials in the whole electrode. Electrodes with a low resistance of 4.5â€…Ω â–¡-1 and high lithium-ion diffusion efficiency of 2.5×10-11  cm2 s-1 can significantly improve the electrochemical kinetics. Subsequently, the batteries demonstrated high energy density, amazing charge/discharge rate and long cycle life.

14.
Angew Chem Int Ed Engl ; 61(44): e202210567, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36093885

RESUMEN

As a key component of batteries, the electrolyte determines the ion transport and interface chemistry of the cathode and anode. In this work, we develop a dual-network structured hydrogel electrolyte composed of polyacrylamide (PAM), sodium alginate (SA) and potassium iodide (KI) for solid-state zinc-air/iodide hybrid batteries. The assembled hybrid battery shows excellent renewability and a long cycling life of 110 h with a high energy efficiency of 80 %. The ion-crosslinked dual-network structure endows the material with improved mechanical strength and increased ionic conductivity. More importantly, the introduction of iodine species not only offers more favorable cathodic kinetics of iodide/iodate redox than oxygen electrocatalysis but also regulates the solvation structure of zinc ions to ensure better interface stability. This work provides significant concepts for developing novel solid-state electrolytes to realize high-performance energy devices and technologies.

15.
Medicine (Baltimore) ; 101(27): e29753, 2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35801792

RESUMEN

Studies of therapeutic endoscopic retrograde cholangiopancreatography (ERCP) in geriatric patients have mainly examined patients with biliary diseases, rather than chronic pancreatitis (CP). This study aimed to evaluate the safety and success rate of therapeutic ERCP in geriatric patients with CP. The medical records of patients with CP aged over 65 years (group A) were retrospectively collected in a tertiary hospital from January 2013 to December 2018. Sex-matched CP patients under 65 years (group B) were randomly selected into the control group (matching ratio = 1:2). The success rate and the complication rate of therapeutic ERCP in 2 groups were compared. The risk factors for post-ERCP pancreatitis were investigated by univariate and multivariate analyses. A total of 268 ERCPs were performed in 179 patients of group A and 612 ERCPs in 358 patients of group B. The success rate of ERCP in group A was similar to that of group B (92.16% vs 92.32%; P = .936). The overall incidence of post-ERCP complications was 7.09% (19/268) and 5.72% (35/612) in group A and B, respectively (P = .436). However, geriatric patients had a significantly increased occurrence of moderate to severe complications (2.61% vs 0.16%; P = .002). Female gender (odds ratio [OR] = 3.40; P = .046), pancreas divisum (OR = 7.15; P = .049), dorsal pancreatogram (OR = 7.40; P = .010), and lithotripsy (OR = 0.15; P = .016) were significantly associated with risk of post-ERCP pancreatitis in geriatric patients. Therapeutic ERCP is safe and feasible in elderly patients with CP. However, occurrence of moderate to severe complications after ERCP increased in geriatric patients.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Pancreatitis Crónica , Anciano , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Femenino , Humanos , Páncreas , Pancreatitis Crónica/etiología , Estudios Retrospectivos
16.
Front Med (Lausanne) ; 9: 872881, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572990

RESUMEN

Background and Aims: Emergency endoscopy is recommended for patients with acute esophageal variceal bleeding (EVB) and their prognosis has improved markedly over past decades due to the increased specialization of endoscopic practice. The study aimed to compare outcomes following emergency endoscopic injection sclerotherapy (EIS) and endoscopic variceal ligation (EVL) in cirrhotic patients with acute EVB. Methods: Cirrhotic patients with acute EVB who underwent emergency endoscopy were retrospectively enrolled from 2013 to 2020 across 34 university hospitals from 30 cities. The primary outcome was the incidence of 5-day rebleeding after emergency endoscopy. Subgroup analysis was stratified by Child-Pugh class and bleeding history. A 1:1 propensity score matching (PSM) analysis was performed. Results: A total of 1,017 and 382 patients were included in EIS group and EVL group, respectively. The 5-day rebleeding incidence was similar between EIS group and EVL group (4% vs. 5%, P = 0.45). The result remained the same after PSM (P = 1.00). Among Child-Pugh class A, B and C patients, there were no differences in the 5-day rebleeding incidence between the two groups after PSM (P = 0.25, 0.82, and 0.21, respectively). As for the patients with or without bleeding history, the differences between EIS group and EVL group were not significant after PSM (P = 1.00 and 0.26, respectively). Conclusion: The nationwide cohort study indicates that EIS and EVL are both efficient emergency endoscopic treatment strategies for acute EVB. EIS should not be dismissed as an economical and effective emergency endoscopic treatment strategy of acute EVB. ClincialTrials.gov number NCT04307264.

17.
Proc Natl Acad Sci U S A ; 119(20): e2202812119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35533282

RESUMEN

Developing facile approaches for preparing efficient electrocatalysts is of significance to promote sustainable energy technologies. Here, we report a facile iron-oxidizing bacteria corrosion approach to construct a composite electrocatalyst of nickel­iron oxyhydroxides combined with iron oxides. The obtained electrocatalyst shows improved electrocatalytic activity and stability for oxygen evolution, with an overpotential of ∼230 mV to afford the current density of 10 mA cm−2. The incorporation of iron oxides produced by iron-oxidizing bacteria corrosion optimizes the electronic structure of nickel­iron oxyhydroxide electrodes, which accounts for the decreased free energy of oxygenate generation and the improvement of OER activity. This work demonstrates a natural bacterial corrosion approach for the facile preparation of efficient electrodes for water oxidation, which may provide interesting insights in the multidisciplinary integration of innovative nanomaterials and emerging energy technologies.


Asunto(s)
Níquel , Oxígeno , Microbiología del Agua , Corrosión , Compuestos Férricos , Hierro , Agua
18.
Materials (Basel) ; 15(4)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35207934

RESUMEN

In this work, radiation experiments and simulations were carried out on perovskite solar cells (PSCs). The experimental results show that the PSCs in this work were robust to proton irradiation but more sensitive to electron irradiation, which is different from the results of previous studies. Simulations based on the Monte Carlo method show that the energy loss at the interface was much higher than that in the material bulk, and the interface was more sensitive to electron incidents.

19.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(5): 470-474, 2022 Sep.
Artículo en Chino | MEDLINE | ID: mdl-37088754

RESUMEN

OBJECTIVE: To investigate the effects of glucocorticoid receptor agonists on hyperalgesia in rats with neuropathic pain (NPP) by regulating nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)/interleukin-1ß (IL-1ß) pathway and its mechanisms. METHODS: Forty SD rats were divided into control group, NPP model group, NPP treated with NLRP3 inhibitor group and dexamethasone treatment group with 10 rats in each group. The NPP rat model was induced by vincristine. The model group was established according to the above method, the NLRP3 inhibitor group was treated with NLRP3 inhibitor (MCC950) after the NPP model was established, and the treatment group was treated with glucocorticoid receptor agonist (dexamethasone) after the model was established according to the design. The rats of the control group were given the same amount of normal saline. After 7 days of intervention, the mechanical pain threshold, thermal pain threshold, morphological changes of spinal dorsal horn, pain factors (prostaglandin E2 (PGE2), substance P (SP), 5-hydroxytryptamine (5-HT)), inflammatory factors (interleukin-8 (IL-8), tumor necrosis factor α (TNF-α), interleukin-6 (IL-6)), and NLRP3/IL-1ß protein expressions were determined and compared among the four groups. RESULTS: Compared with the model group, the pathological changes of spinal dorsal horn neurons in NLRP3 inhibitor group and treatment group were alleviated significantly, the arrangement of neurons was tended to be close, the number of neurons was gradually returned to normal, and the pyknosis of neurons was decreased. Compared with the control group, the mechanical pain threshold and thermal pain threshold of the model group were decreased significantly (P<0.05), and the expressions of inflammatory factors, pain factors and NLRP3, IL-1ß protein were increased significantly (P<0.05); compared with the model group, the mechanical pain threshold and thermal pain threshold of the NLRP3 inhibitor group and the dexamethasone treatment group were increased significantly (P<0.05), and the expressions of inflammatory factors, pain factors and NLRP3, IL-1ß protein were decreased significantly (P< 0.05). The difference between NLRP3 inhibitor group and treatment group was not statistically significant (P>0.05). CONCLUSION: Glucocorticoid receptor agonists may reduce the hyperalgesia of neuropathic pain rat model by down regulating NLRP3/IL-1ß pathway, which may be the mechanism of dexamethasone on antiinflammatory of analgesia in early stage of NPP.


Asunto(s)
Hiperalgesia , Neuralgia , Ratas , Animales , Hiperalgesia/tratamiento farmacológico , Receptores de Glucocorticoides , Ratas Sprague-Dawley , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Neuralgia/tratamiento farmacológico , Interleucina-6 , Dexametasona
20.
Small ; 18(7): e2106606, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34874623

RESUMEN

Designing cost-effective and high-efficiency bifunctional electrocatalysts for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) occurred at air electrodes is vitally significant yet challenging for Zn-air batteries (ZABs). In this work, a zinc substrate induced fabrication is reported of free-standing nanocarbon hybrid film which shows good bifunctional activity and can be directly used as the air electrode in the rechargeable ZABs. The designed nanocarbon film in Zn-air battery provides a satisfactory power density of 185 mW cm-2 and cycling stability for 1200 h under the current density of 10 mA cm-2 . This hybrid film also gives a solid-state ZAB excellent flexibility with a power density of 160 mW cm-2 . The free-standing hybrid with abundant cobalt-nitrogen-carbon species coupled with porous architecture would be the original factor for its satisfactory performance of rechargeable ZABs. This work would pave an ideal way to design integrated electrode with high electrocatalytic performance towards electrochemical energy technologies.

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