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1.
Aust Crit Care ; 37(1): 111-119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38087684

RESUMO

BACKGROUND: The negative experiences of intensive care unit (ICU) patients seriously affect their quality of life and survival outcomes. Thus, it is of great significance to evaluate the monitoring experience of ICU patients for the clinical improvement of their experiences and promote interventions. OBJECTIVES: The objective of this study was to investigate patients' experiences of ICU and to understand the sources of patient experience and influencing factors. METHODS: From November 2021 to September 2022, a cross-sectional survey was conducted with 600 inpatients from four grade A-III hospitals in western China. Data were collected using the Chinese version of the Intensive Care Experience Questionnaire. RESULTS: 585 valid questionnaires were collected, the response rate was 97.5%. ICU patients in western China scored below-the-average for their intensive care experience. Family monthly income, occupation types, medical payment method, type of ICU, ICU admission plan, ICU admission times, mechanical ventilation use, fertility status, analgesia, sedation, and Acute Physiology and Chronic Health Evaluation II scores are important factors influencing ICU patients' intensive care experience. CONCLUSIONS: Medical staff need to pay attention to patient experience, improve the awareness of patient stressors and influencing factors, design nursing programs conducive to patient-positive experience, and promote interventions to further improve the long-term prognosis of patients. The results of this study can also be used as a set of nursing-sensitive indicators for evaluating nursing structure, process, and outcomes.


Assuntos
Unidades de Terapia Intensiva , Qualidade de Vida , Humanos , Estudos Transversais , Cuidados Críticos , China
2.
J Psychosoc Oncol ; 41(4): 457-474, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36370039

RESUMO

BACKGROUND: Similar to the side effects of cancer treatment, financial toxicity (FT) can affect the quality of life of patients, which has attracted increasing attention in the field of oncology. Despite the fact that the estimated prevalence and risk factors of FT are widely reported, these results have not been synthesized. OBJECTIVES: This review is aimed to systematically assess the prevalence and risk factors of self-reported FT. DESIGN: Systematic review and meta-analyses. DATA SOURCES: A computer search of English literature was conducted using databases of PubMed, EMBASE, Web of Science, PsycINFO, and CINAHL, and reference lists of the qualified articles were also included between January 2010 and September 2021. Observational studies that reported the prevalence or risk factors of FT using subjective measures were included. METHODS: The systematic review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The risk of bias was assessed by the NIH observational cohort and cross-sectional study quality assessment tool. The data were extracted by two reviewers and listed in a descriptive table for meta-analyses. RESULTS: In the 22 studies available for meta-analyses of pooled prevalence of FT, the result was estimated to be 45% (95% CI: 38% to 53%, I2 = 97.3%, P < 0.001) based on a random-effects model. The pooled analysis identified 9 potential risk factors of FT (7 in ß and 8 in OR): low income (OR = 2.48, 95% CI: 1.72 to 3.24, I2 = 3.1%, P < 0.001), greater annual OOP (ß = -4.26, 95% CI: -6.95 to -1.57, I2 = 0%, P = 0.002), younger age (OR = 2.05, 95% CI: 1.56 to 2.54, I2 = 0%, P < 0.001), no private insurance (OR = 1.69, 95% CI: 1.02 to 2.37, I2 = 0%, P < 0.001), unmarried (OR = 1.10, 95% CI: 0.95 to 1.25, I2 = 53,3%, P < 0.001), nonwhite (OR = 1.59, 95% CI: 1.33 to 1.85, I2 = 0%, P < 0.001), advanced cancer (ß = -4.74, 95% CI: -6.90 to -2.57, I2 = 0%, P < 0.001), unemployed (ß = -2.90, 95% CI: -5.71 to -0.63, I2 = 75,7%, P < 0.001), more recent diagnosis (OR = 1.31, 95% CI: 1.04 to 1.57, I2 = 0%, P < 0.001). CONCLUSION: This systematic review reported a pooled prevalence of self-reported FT of 45%. Low income, greater annual OOP (Out of pocket), younger age, unmarried, unemployed, nonwhite, no private insurance, advanced cancer, and more recent diagnosis constituted risk factors for self-reported FT. The research on risk factors for FT can provide a theoretical basis for medical staff to evaluate and intervene in the FT among cancer survivors.


Assuntos
Sobreviventes de Câncer , Neoplasias , Humanos , Qualidade de Vida , Prevalência , Autorrelato , Estudos Transversais , Estresse Financeiro , Fatores de Risco , Neoplasias/terapia
3.
Small ; 18(37): e2203674, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35941099

RESUMO

The unstable anode/electrolyte interface (AEI) triggers the corrosion reaction and dendrite formation during cycling, hindering the practical application of zinc metal batteries. Herein, for the first time, l-cysteine (Cys) is employed to serve as an electrolyte additive for stabilizing the Zn/electrolyte interface. It is revealed that Cys additives tend to initially approach the Zn surface and then decompose into multiple effective components for suppressing parasitic reactions and Zn dendrites. As a consequence, Zn|Zn symmetric cells using trace Cys additives (0.83 mm) exhibit a steady cycle life of 1600 h, outperforming that of prior studies. Additionally, an average Coulombic efficiency of 99.6% for 250 cycles is also obtained under critical test conditions (10 mA cm-2 /5 mAh cm-2 ). Cys additives also enable Zn-V2 O5 and Zn-MnO2 full cells with an enhanced cycle stability at a low N/P ratio. More importantly, Cys/ZnSO4 electrolytes are demonstrated to be still effective after resting for half year, favoring the practical production.


Assuntos
Cisteína , Zinco , Eletrodos , Eletrólitos , Compostos de Manganês , Metais , Óxidos
4.
Cell Mol Neurobiol ; 40(4): 587-602, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31828466

RESUMO

Neurodegenerative diseases all share several common features such as involvement of oxidative damage and mitochondrial dysfunction in pathogenesis. Oxidative stress induced by overproduction of mitochondrial reactive oxygen species (ROS) or impairment of the antioxidant deficiency results in mitochondrial dysfunction and initiation of the cell death cascade. Berberine (BBR), a traditional Chinese medicine, has been reported to exert anti-oxidative stress and anti-apoptosis effect in CNS diseases. However, the mechanism of BBR on regulating mitophagy and protecting mitochondrial function under oxidative stress remains unclear. In present study, we evaluated the beneficial effects of BBR on the tert-butyl hydroperoxide (t-BHP)-induced cytotoxicity. Furthermore, we explored the protective role of BBR in mitochondrial function and mitophagy under oxidative stress in PC-12 cells. Our results demonstrated that BBR effectively inhibited t-BHP-induced apoptosis which is associated with the decreased leakage of lactate dehydrogenase (LDH) and ROS overproduction. Moreover, BBR significantly suppressed cytochrome c expression, upregulated the ratio of Bcl-2/Bax, and ameliorated mitochondrial dysfunction by optimizing mitochondria membrane potential (ΔΨm) status and ATP production. In addition, BBR reduced the expression of autophagy-specific marker LC3, SQTM1/p62, and maintained lysosome normal function which involved the restoration of upstream signaling pathway AKT and mTOR phosphorylation level. Collectively, these findings suggested that BBR protects PC-12 cells from oxidative injury through inhibiting ROS level, mitochondria dysfunction, and mitophagy via PI3K/AKT/mTOR signaling pathways, which suggest a potential therapeutic strategy for oxidative stress and neurotoxic damages.


Assuntos
Berberina/farmacologia , Mitocôndrias/patologia , Estresse Oxidativo/efeitos dos fármacos , terc-Butil Hidroperóxido/toxicidade , Animais , Morte Celular/efeitos dos fármacos , Cromonas/farmacologia , Citocromos c/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitofagia/efeitos dos fármacos , Morfolinas/farmacologia , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos
5.
J Nanosci Nanotechnol ; 17(1): 341-7, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29620833

RESUMO

LiFePO4 (LFP) microparticles coated homogeneously with three-dimensional (3D) carbon nanotube (CNT) conductive networks were successfully prepared via a simple and effective ball milling method by controlling Polyvinylidene fluoride (PVDF) content in cathode electrode slurry. Scanning electron microscopy (SEM) demonstrated that the electrical bridge between the LFP could be well modulated by varying the amount of the CNTs and PVDF. The LFP/CNTs composite with 3 wt% CNTs and 5 wt% PVDF, in which CNTs are embedded in the microspheres homogeneously, possesses the best 3D CNT conductive networks and exhibits the best electrochemical property with high capacity retention of 95.72% at 0.25 C after 50 cycles. Essentially, in comparison with those samples without CNT networks, this CNT network structure can greatly enhance the electrical conductivity, thus markedly improving the electrochemical performance. (LFP) microparticles coated homogeneously with three-dimensional (3D) carbon nanotube (CNT) conductive networks were successfully prepared via a simple and effective ball milling method by controlling Polyvinylidene fluoride (PVDF) content in cathode electrode slurry. Scanning electron microscopy (SEM) demonstrated that the electrical bridge between the LFP could be well modulated by varying the amount of the CNTs and PVDF. The LFP/CNTs composite with 3 wt% CNTs and 5 wt% PVDF, in which CNTs are embedded in the microspheres homogeneously, possesses the best 3D CNT conductive networks and exhibits the best electrochemical property with high capacity retention of 95.72% at 0.25 C after 50 cycles. Essentially, in comparison with those samples without CNT networks, this CNT network structure can greatly enhance the electrical conductivity, thus markedly improving the electrochemical performance.

6.
BMC Cancer ; 15: 917, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26582454

RESUMO

BACKGROUND: Standardized chemotherapy used in cancer patients with severe kidney insufficiency is ineffective. Although there are some pharmacokinetic studies on cyclophosphamide in kidney insufficiency patients, to the best of our knowledge, the pharmacokinetics and safety of combination of cyclophosphamide and docetaxel as postoperative chemotherapy in a patient with early stage breast cancer undergoing hemodialysis is unclear thus far. CASE PRESENTATION: The patient received regular TC regimen (cyclophosphamide 600 mg/m2, docetaxel 75 mg/m2). She underwent hemodialysis 48 h after chemotherapy. Blood samples at multiple time-points were collected for determination of plasma levels of cyclophosphamide and docetaxel. Pharmacokinetic analyses indicated that compared with the reference data, the in vivo half-life (66.96 h) and drug exposure (150%) of cyclophosphamide significantly increased; however, pharmacokinetic parameters of docetaxel was unaffected. Patient developed grade I thrombocytopenia and grade III leukopenia without any other severe adverse reactions. In total, four cycles of treatment were completed. After the chemotherapy, the patient received tamoxifen as endocrine therapy for one and a half years. No recurrence was reported. CONCLUSION: These results suggest that the standard TC regimen is mostly safe and could be used as postoperative adjuvant chemotherapy for hemodialysis patients with early stage breast cancer.


Assuntos
Antineoplásicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Ciclofosfamida/farmacocinética , Diálise Renal , Insuficiência Renal Crônica/metabolismo , Taxoides/farmacocinética , Antineoplásicos/efeitos adversos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Ciclofosfamida/efeitos adversos , Docetaxel , Feminino , Humanos , Pessoa de Meia-Idade , Período Pós-Operatório , Insuficiência Renal Crônica/terapia , Taxoides/efeitos adversos
7.
Nanotechnology ; 25(47): 475601, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25369800

RESUMO

Nitrogen-doped carbon nanotubes (NCNTs) were prepared using a simple ultrasonic spray pyrolysis method. The precursor concentration effect was examined to effectively control alignment, open tip and diameter of the NCNTs by changing xylene/cyclohexylamine ratio. The structure and morphology of the resultant NCNTs were characterized by scanning electron microscopy, transmission electron microscopy and x-ray photoelectron spectroscopy. The degree of alignment and the diameter of the NCNTs increased as the xylene/cyclohexylamine precursor mixture was changed from 0 to 35% cyclohexylamine. This precursor composition also caused a large number of open-ended nanotubes to form with graphite layers inside the cavities of the NCNTs. However, further increase cyclohexylamine content in the precursor reduced the degree of alignment and diameter of the NCNTs. We demonstrate control over the NCNT alignment and diameter, along with the formation of open-ended nanotube tips, and propose a growth mechanism to understand how these properties are interlinked.

8.
J Colloid Interface Sci ; 675: 630-638, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38991277

RESUMO

Aqueous Zn-S batteries (AZSBs) have garnered increasing attention in the energy storage field owing to their high capacity, energy density, and cost effectiveness. Nevertheless, sulfur (S) cathodes face challenges, primarily stemming from sluggish reaction kinetics and the formation of an irreversible byproduct (SO42-) during the charge, hindering the progress of AZSBs. Herein, Te-S bonds within S-based cathodes were introduced to enhance electron and ion transport and facilitate the conversion reaction from zinc sulfide (ZnS) to S. This was achieved by constructing heteroatomic TeS-x@Ketjen black composite cathodes (HM-TeS-x@KB, where x  = 36, 9, and 4). The HM-TeS-9@KB electrode exhibits long-term cycling stability, maintaining a capacity decay rate of 0.1 % per cycle over 450 cycles at a current density of 10 A g-1. Crucially, through a combination of experimental data analysis and theoretical calculations, the impact mechanism of Te on the charge and discharge of S active materials within the HM-TeS-9@KB cathode in AZSBs was investigated. The presence of Te-S bonds boost the intrinsic conductivity and wettability of the HM-TeS-9@KB cathode. Furthermore, during the charge, the interaction of preferentially oxidized Te with S atoms within ZnS promotes the oxidation reaction from ZnS to S and suppresses the irreversible side reaction between ZnS and H2O. These findings indicate that the heteroatomization of chalcogen S molecules represents a promising approach for enhancing the electrochemical performance of S cathodes in AZSBs.

9.
Front Oncol ; 13: 1239781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810985

RESUMO

Background: The relationship between frailty and the long-term clinical outcome of gastric cancer (GC) patients has not yet been established, although frailty is associated with a poor short-term outcome. The impact of frailty on long-term survival of GC patients was investigated through a systematic review and meta-analysis. Methods: Observational studies with longitudinal follow-ups for a minimum of one year were identified through a search of the PubMed, Embase, Cochrane Library, and Web of Science databases, in accordance with the objective of the meta-analysis. Combining the findings was achieved using a random-effects model, which accounted for inter-study heterogeneity. Results: Ten datasets from nine cohort studies were included, which involved 7613 patients with GC. A total of 2074 patients (27.2%) were with frailty at baseline, and the mean follow-up duration was 48.1 months. A pooled analysis of the results showed that frailty was linked to a poor long-term overall survival in GC patients (risk ratio [RR]: 1.65, 95% confidence interval [CI]: 1.27 to 2.13, p < 0.001; I2 = 80%). Sensitivity analysis showed consistent results in older patients (≥ 65 years, RR: 1.51, p = 0.002) and the oldest old (≥ 80 years, RR: 1.41, p = 0.01). In addition, frailty was also associated with poor long-term progression-free survival (RR: 1.65, 95% CI: 1.39 to 1.96, p < 0.001; I2 = 0%) and disease-specific survival (RR: 1.71, 95% CI: 1.23 to 2.37, p = 0.001; I2 = 4%). Conclusion: Frailty is associated with poor long-term survival of patients with GC.

10.
IEEE Trans Biomed Eng ; 69(11): 3345-3355, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35439122

RESUMO

Magnetic Resonance Elastography (MRE) is a developing imaging technique that enables non-invasive estimation of tissue mechanical properties through the combination of induced mechanical displacements in the tissue and Magnetic Resonance Imaging (MRI). The mechanical drivers necessary to produce shear waves in the tissue have been a focus of engineering effort in the development and refinement of MRE. The potential targeting of smaller and stiffer tissues calls for increases in actuation frequency and refinement of mechanical driver positioning. Furthermore, the anisotropic nature of soft tissues results in driver position related changes in observed displacement wave patterns. These challenges motivate the investigation and development of the concept of active MRE driver positioning through visual servoing under MR imaging. OBJECTIVE: This work demonstrates the initial prototype of an MRE driver positioning system, allowing capture of displacement wave patterns from various mechanical vibration loading angles under different vibration frequencies through MR imaging. METHODS: Three different configurations of the MRE driver positioning robot are tested with an intervertebral disc (IVD) shaped gel phantom. RESULTS: Both the octahedral shear stress signal to noise ratio (OSS-SNR) and estimated stiffness show statistically significant dependence on driver configuration in each of the three phantom IVD regions. CONCLUSION: This dependence demonstrates that driver configuration is a critical factor in MRE, and that the developed robot is capable of producing a range of configurations. SIGNIFICANCE: This work presents the first demonstration of an active, imaging guided MRE driver positioning system, with significance for the future application of MRE to a wider range of human tissues.


Assuntos
Técnicas de Imagem por Elasticidade , Robótica , Humanos , Técnicas de Imagem por Elasticidade/métodos , Imagens de Fantasmas , Razão Sinal-Ruído , Imageamento por Ressonância Magnética/métodos
11.
ACS Appl Mater Interfaces ; 14(50): 55577-55586, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36475580

RESUMO

K metal holds great promise as the ultimate anode candidate for K-ion batteries because of its high theoretical capacity and low operating potential. However, due to its high viscosity and poor mechanical processability, it remains challenging to manufacture potassium anodes with precise parameters by a simple and executable method. In this work, a high-performance potassium-carbon nanotubes (K@CNTs) composite film electrode with a three-dimensional (3D) skeleton and superior processability is prepared by simply incorporating CNTs into molten potassium. The in situ potassiation reaction between CNTs and molten K formed potassium carbide (KC8) so as to obtain a solid-liquid mixture, which can reduce the surface tension of molten potassium and promote the preparation of the K@CNTs film electrode. The composite electrode can be molded into a variety of shapes and thicknesses in accurate dimensions. The porous, well-conducting CNTs act as a 3D skeleton uniformly distributed in the K metal, providing adequate surface and space to accommodate and attract K metal, thereby inhibiting the growth of the potassium dendrites and the volume expansion upon cycling. As a result, the K@CNTs composite anode exhibits excellent cyclability and rate capability in both symmetric and full cells. The superior processability and excellent electrochemical performance make this composite an ideal anode candidate for commercial applications in potassium metal batteries.

12.
Front Oncol ; 12: 1011052, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387157

RESUMO

Objective : Using the Comprehensive Score for Financial Toxicity (COST) tool to measure financial toxicity (FT) among nasopharyngeal cancer (NPC) patients in western China and investigate the association between FT and psychological distress. Methods: We conducted a cross-sectional study of survivors with NPC in a tertiary oncology hospital in China. FT was assessed using the COST (Chinese version), a validated instrument widely used both at home and abroad. The NCCN Distress Thermometer (DT) was used to measure psychological distress. A multivariate logistic regression model was built to determine factors associated with FT, and the Pearson correlation was used to assess the correlation between COST and DT scores. Results: Of 210 patients included in this study, the mean FT score was 16.3 (median: 22.5, SD: 9.7), and the prevalence of FT was 66.2% (mild FT: 37.1%, moderate FT: 50.5%, severe FT: 2.4%). Suggested by the logistic regression model, 5 variables were associated with increased FT: unemployed, no commercial insurance, receiving lower annual income, advanced cancer, and receiving targeted therapy. The Pearson correlation showed a significantly moderate correlation between financial toxicity and psychological distress (r= -0.587, P < 0.001). Conclusion: Patients with nasopharyngeal carcinoma (NPC) in western China demonstrated higher self-reported financial toxicity (FT) associated with factors including unemployed, no commercial insurance, receiving lower annual income, advanced cancer, and receiving targeted therapy. These predictors will help clinicians identify potential patients with FT in advance and conduct effective psychological interventions.

13.
IEEE Trans Biomed Eng ; 68(3): 807-814, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32870782

RESUMO

Recent developments in the field of cellular therapeutics have indicated the potential of stem cell injections directly to the spinal cord. Injections require either open surgery or a Magnetic Resonance Imaging (MRI) guided injection. Needle positioning during MRI imaging is a significant hurdle to direct spinal injection, as the small target region and interlaminar space require high positioning accuracy. OBJECTIVE: To improve both the procedure time and positioning accuracy, an MRI guided robotic needle positioning system is developed. METHODS: The robot uses linear piezoelectric motors to directly drive a parallel plane positioning mechanism. Feedback is provided through MRI during the orientation procedure. Both accuracy and repeatability of the robot are characterized. RESULTS: This system is found to be capable of repeatability below 51 µm. Needle endpoint error is limited by imaging modality, but is validated to 156 µm. CONCLUSION: The reported robot and MRI image feedback system is capable of repeatable and accurate needle guide positioning. SIGNIFICANCE: This high accuracy will result in a significant improvement to the workflow of spinal injection procedures.


Assuntos
Robótica , Injeções Espinhais , Imageamento por Ressonância Magnética , Agulhas , Imagens de Fantasmas
14.
Adv Mater ; 33(38): e2100445, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34338350

RESUMO

Zn anodes suffer from poor Coulombic efficiency (CE) and serious dendrite formation due to the unstable anode/electrolyte interface (AEI). The electrical double layer (EDL) structure formed before cycling is of great significance for building stable solid electrolyte interphase (SEI) on Zn surface but barely discussed in previous research about the stabilization of Zn anode. Herein, saccharin (Sac) is introduced as electrolyte additive for regulating the EDL structure on the AEI. It is found that Sac derived anions are preferentially adsorbed on the Zn metal surface instead of water dipole, creating a new H2 O-poor EDL structure. Moreover, the unique SEI is also detected on the Zn surface due to the decomposition of Sac anions. Both are proved to be capable of modulating Zn deposition behavior and preventing side reactions. Encouragingly, Zn|Zn symmetric cells using Sac additive deliver a high cumulative plated capacity of 2.75 Ah cm-2 and a high average CE of 99.6% under harsh test condition (10 mA cm-2 , 10 mAh cm-2 ). The excellent stability is also achieved at a high rate of 40 mA cm-2 . The effectiveness of this Sac additive is further demonstrated in the Zn-MnO2 full cells.

15.
Nanomicro Lett ; 13(1): 192, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34515838

RESUMO

Oxygen-containing functional groups were found to effectively boost the K+ storage performance of carbonaceous materials, however, the mechanism behind the performance enhancement remains unclear. Herein, we report higher rate capability and better long-term cycle performance employing oxygen-doped graphite oxide (GO) as the anode material for potassium ion batteries (PIBs), compared to the raw graphite. The in situ Raman spectroscopy elucidates the adsorption-intercalation hybrid K+ storage mechanism, assigning the capacity enhancement to be mainly correlated with reversible K+ adsorption/desorption at the newly introduced oxygen sites. It is unraveled that the C=O and COOH rather than C-O-C and OH groups contribute to the capacity enhancement. Based on in situ Fourier transform infrared (FT-IR) spectra and in situ electrochemical impedance spectroscopy (EIS), it is found that the oxygen-containing functional groups regulate the components of solid electrolyte interphase (SEI), leading to the formation of highly conductive, intact and robust SEI. Through the systematic investigations, we hereby uncover the K+ storage mechanism of GO-based PIB, and establish a clear relationship between the types/contents of oxygen functional groups and the regulated composition of SEI.

17.
ACS Appl Mater Interfaces ; 13(17): 19894-19903, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33881819

RESUMO

Exploring active materials with a high rate capability and long lifespan for sodium ion batteries attracts much more attention and plays an important role in realizing clean energy storage and conversion. The strategy of optimizing the electronic structure by atomic element substitution within MoS2 layers was employed to change the inherent physical property. The enhanced electronic conductivity from a decreased bandgap and increased surface Na+ adsorption energy can efficiently and dramatically optimize the electrochemical performance for sodium storage. Attempting to limit the large volume variation and avoid MoS2 nanosheet stacking and restacking, numerous nanosheets are in situ grown into a designed hierarchical mesopore carbon matrix. This structure can tightly capture the nanosheets to prevent them from aggregating and offer a sufficient buffer zone for alleviating severe volume changes during the discharging/charging process, contributing remarkably to the structural integrity and superior rate performance of electrodes.

18.
Am J Nephrol ; 31(4): 363-74, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20332614

RESUMO

BACKGROUND: Recent studies suggest the involvement of the adenosine monophosphate-activated serine/threonine protein kinase (AMPK) pathway in the pathogenesis of diabetic nephropathy (DN). Resveratrol, an agent that activates AMPK, may have the potential to protect against the development of DN. This study was designed to investigate the therapeutic effects of resveratrol on renal hypertrophy in early-stage diabetes and the underlying mechanisms. METHOD: Molecular and structural changes involved in the pathogenesis of DN were tested in a rat model of early-stage diabetes. Renal mesangial cells (RMCs) were cultured in media containing different concentrations of glucose with or without resveratrol. Cellular DNA synthesis was assayed by measuring (3)H-thymidine incorporation. The phosphorylation status of AMPK, eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1), and phospho- ribosomal protein S6 (S6) was analyzed by Western blot. RESULTS: Resveratrol reduced plasma creatinine and urinary albumin excretion and attenuated renal hypertrophy without affecting blood glucose levels. Moreover, resveratrol activated AMPK and inhibited phosphorylation of 4E-BP1 and S6 in diabetic rat kidneys. In vitro, resveratrol blocked high glucose-induced dephosphorylation of AMPK and phosphorylation of 4E-BP1 and S6 and strongly inhibited both the DNA synthesis and proliferation of RMCs. CONCLUSION: These findings suggest the possibility that resveratrol exerts antiproliferative, antihypertrophic effects by activating AMPK and reducing 4E-BP1 and S6 phosphorylation, thus suppressing the development and progression of DN.


Assuntos
Nefropatias Diabéticas/prevenção & controle , Rim/patologia , Proteínas Quinases/fisiologia , Estilbenos/uso terapêutico , Quinases Proteína-Quinases Ativadas por AMP , Animais , Hipertrofia/prevenção & controle , Masculino , Fosforilação/efeitos dos fármacos , Proteínas Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Resveratrol , Estilbenos/farmacologia
19.
Nanomicro Lett ; 13(1): 1, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34138186

RESUMO

Potassium-ion batteries (PIBs) are attractive for grid-scale energy storage due to the abundant potassium resource and high energy density. The key to achieving high-performance and large-scale energy storage technology lies in seeking eco-efficient synthetic processes to the design of suitable anode materials. Herein, a spherical sponge-like carbon superstructure (NCS) assembled by 2D nanosheets is rationally and efficiently designed for K+ storage. The optimized NCS electrode exhibits an outstanding rate capability, high reversible specific capacity (250 mAh g-1 at 200 mA g-1 after 300 cycles), and promising cycling performance (205 mAh g-1 at 1000 mA g-1 after 2000 cycles). The superior performance can be attributed to the unique robust spherical structure and 3D electrical transfer network together with nitrogen-rich nanosheets. Moreover, the regulation of the nitrogen doping types and morphology of NCS-5 is also discussed in detail based on the experiments results and density functional theory calculations. This strategy for manipulating the structure and properties of 3D materials is expected to meet the grand challenges for advanced carbon materials as high-performance PIB anodes in practical applications.

20.
RSC Adv ; 10(31): 18115-18123, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35517231

RESUMO

Even after a decade of research and rapid development of lithium-sulfur (Li-S) batteries, the infamous shuttle effect of lithium polysulfide is still the major challenge hindering the commercialization of Li-S batteries. In order to further address this issue, a functionalized PP separator is obtained through selective single-sided chemical tailoring, and then organosiloxane fumigation grafting. During the charge-discharge process, the grafted functional groups can effectively block the transportation of the dissolved polysulfides through strong chemical anchoring, inhibit the shuttle effect and greatly enhance the cycle stability of the Li-S battery. Interestingly, the specially designed single-sided enlarged channel structure formed by chemical tailoring can well accommodate the deposition with intermediate polysulfides on the separator surface toward the cathode chamber, resulting in enhanced initial discharge capacity and rate performance. Compared to the battery assembled with PP, the Li-S battery employing the separator grafted with a 3-ureidopropyltrimethoxysilane (PP-O x--U) displays better electrochemical performance. Even at 2C, it can still deliver a high capacity of 786 mA h g-1, and retain a capacity of 410 mA h g-1 with a low capacity fading of 0.095% per cycle over 500 cycles. This work provides a very promising and feasible strategy for the development of a special functionalization PP separator for Li-S batteries with high electrochemical performance.

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