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1.
J Clin Neurosci ; 123: 137-147, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574685

RESUMO

OBJECTIVE: This study aimed to analyze the risk factors for recurrent ischemic stroke in patients with symptomatic intracranial atherosclerotic stenosis (ICAS) who underwent successful stent placement and to establish a nomogram prediction model. METHODS: We utilized data from a prospective collection of 430 consecutive patients at Jining NO.1 People's Hospital from November 2021 to November 2022, conducting further analysis on the subset of 400 patients who met the inclusion criteria. They were further divided into training (n=321) and validation (n=79) groups. In the training group, we used univariate and multivariate COX regression to find independent risk factors for recurrent stroke and then created a nomogram. The assessment of the nomogram's discrimination and calibration was performed through the examination of various measures including the Consistency index (C-index), the area under the receiver operating characteristic (ROC) curves (AUC), and the calibration plots. Decision curve analysis (DCA) was used to evaluate the clinical utility of the nomogram by quantifying the net benefit to the patient under different threshold probabilities. RESULTS: The nomogram for predicting recurrent ischemic stroke in symptomatic ICAS patients after stent placement utilizes six variables: coronary heart disease (CHD), smoking, multiple ICAS, systolic blood pressure (SBP), in-stent restenosis (ISR), and fasting plasma glucose. The C-index (0.884 for the training cohort and 0.87 for the validation cohort) and the time-dependent AUC (>0.7) indicated satisfactory discriminative ability of the nomogram. Furthermore, DCA indicated a clinical net benefit from the nomogram. CONCLUSIONS: The predictive model constructed includes six predictive factors: CHD, smoking, multiple ICAS, SBP, ISR and fasting blood glucose. The model demonstrates good predictive ability and can be utilized to predict ischemic stroke recurrence in patients with symptomatic ICAS after successful stent placement.


Assuntos
Arteriosclerose Intracraniana , AVC Isquêmico , Nomogramas , Recidiva , Stents , Humanos , Masculino , Feminino , Arteriosclerose Intracraniana/cirurgia , Arteriosclerose Intracraniana/diagnóstico por imagem , Pessoa de Meia-Idade , AVC Isquêmico/cirurgia , AVC Isquêmico/etiologia , Idoso , Fatores de Risco , Estudos Prospectivos , Constrição Patológica/cirurgia
2.
Adv Mater ; 35(1): e2208237, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36239267

RESUMO

Growth of dendrites, the low plating/stripping efficiency of Zn anodes, and the high freezing point of aqueous electrolytes hinder the practical application of aqueous Zn-ion batteries. Here, a zwitterionic osmolyte-based molecular crowding electrolyte is presented, by adding betaine (Bet, a by-product from beet plant) to the aqueous electrolyte, to solve the abovementioned problems. Substantive verification tests, density functional theory calculations, and ab initio molecular dynamics simulations consistently reveal that side reactions and growth of Zn dendrites are restrained because Bet can break Zn2+ solvation and regulate oriented 2D Zn2+ deposition. The Bet/ZnSO4 electrolyte enables superior reversibility in a Zn-Cu half-cell to achieve a high Coulombic efficiency >99.9% for 900 cycles (≈1800 h), and dendrite-free Zn plating/stripping in Zn-Zn cells for 4235 h at 0.5 mA cm-2 and 0.5 mAh cm-2 . Furthermore, a high concentration of Bet lowers the freezing point of the electrolyte to -92 °C via the molecular-crowding effect, which ensures the stable operation of the aqueous batteries at -30 °C. This innovative concept of such a molecular crowding electrolyte will inject new vitality into the development of multifunctional aqueous electrolytes.


Assuntos
Antioxidantes , Zinco , Temperatura , Betaína , Eletrodos
3.
Eur J Med Res ; 27(1): 38, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35272706

RESUMO

BACKGROUND: Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is an autoimmune disorder characterized by complex neuropsychiatric syndromes during disease onset. Although this disease has been well documented in the last decade, clinical characteristics of anti-NMDA receptor encephalitis in patients with long-term diagnostic history of mental disorders remain unclear. METHODS: Here, we reviewed and analyzed series of anti-NMDA receptor encephalitis patients with a long-term medical history of psychiatric disorders through a review of literature using PubMed, web of science and Embase database. In addition, we described a patient of anti-NMDA receptor encephalitis with a long-term history of major depressive disorder. RESULTS: A total of 14 patients with anti-NMDA receptor encephalitis and a long-term history of mental disorders were included in our study. We found that most patients were adult (92.9%) and female (78.6%). These patients often first visited a psychiatric department (71.43%). The mean disease course of psychiatric disorders was more than 9 years. Speech impairment (71.4%), abnormal behaviors (64.3%), and catatonia (64.3%) were the most common clinical symptoms. Most patients (85.7%) had a satisfactory prognosis after immunotherapy. CONCLUSION: Anti-NMDA receptor encephalitis in individuals with mental disorders is an underestimated condition, yet it presents complex clinical symptoms. Mental and behavioral impairments are more frequently observed in newly diagnosed anti-NMDA receptor encephalitis patients with a long-term history of mental disorders than those without mental illness. A diagnosis of anti-NMDA receptor encephalitis should be considered when patients with mental illness show sudden fluctuations in psychiatric symptoms.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Imunoterapia/métodos , Transtornos Mentais/complicações , Adulto , Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Encefalite Antirreceptor de N-Metil-D-Aspartato/terapia , Seguimentos , Humanos , Masculino , Fatores de Tempo
4.
ACS Appl Mater Interfaces ; 12(5): 5958-5967, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31922398

RESUMO

The practical application of Li-S batteries is hampered because of their poor cycling stability caused by electrolyte-dissolved lithium polysulfides. Dual functionalities such as strong chemical adsorption stability and high conductivity are highly desired for an ideal host material for the sulfur-based cathode. Herein, a uniform polypyrrole layer-coated sulfur/graphene aerogel composite is designed and synthesized using a novel vapor-phase deposition method. The polypyrrole layer simultaneously acts as a host and an adsorbent for efficient suppression of polysulfide dissolution through strong chemical interaction. The density functional theory calculations reveal that the polypyrrole could trap lithium polysulfides through stronger bonding energy. In addition, the deflation of sulfur/graphene hydrogel during the vapor-phase deposition process enhances the contact of sulfur with matrices, resulting in high sulfur utilization and good rate capability. As a result, the synthesized polypyrrole-coated sulfur/graphene aerogel composite delivers specific discharge capacities of 1167 and 409.1 mA h g-1 at 0.2 and 5 C, respectively. Moreover, the composite can maintain a capacity of 698 mA h g-1 at 0.5 C after 500 cycles, showing an ultraslow decay rate of 0.03% per cycle.

5.
Nat Commun ; 10(1): 4793, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641115

RESUMO

Polysulfide dissolution and slow electrochemical kinetics of conversion reactions lead to low utilization of sulfur cathodes that inhibits further development of room-temperature sodium-sulfur batteries. Here we report a multifunctional sulfur host, NiS2 nanocrystals implanted in nitrogen-doped porous carbon nanotubes, which is rationally designed to achieve high polysulfide immobilization and conversion. Attributable to the synergetic effect of physical confinement and chemical bonding, the high electronic conductivity of the matrix, closed porous structure, and polarized additives of the multifunctional sulfur host effectively immobilize polysulfides. Significantly, the electrocatalytic behaviors of the Lewis base matrix and the NiS2 component are clearly evidenced by operando synchrotron X-ray diffraction and density functional theory with strong adsorption of polysulfides and high conversion of soluble polysulfides into insoluble Na2S2/Na2S. Thus, the as-obtained sulfur cathodes exhibit excellent performance in room-temperature Na/S batteries.

6.
Eur Neurol ; 76(5-6): 256-260, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27760417

RESUMO

BACKGROUND: With carotid artery stenosis, infarcts can occur in the cortical or internal watershed areas, or both. The timing of carotid artery stenting (CAS) after a cerebral watershed infarction (CWI) is not yet codified. In this retrospective study, we analyzed the safety and clinical effect of early CAS for CWI patients due to carotid artery stenosis. METHODS: Between March 2011 and April 2014, 120 CWI patients with ipsilateral carotid artery stenosis were recruited. Of these 120 patients, 63 received CAS within 7 days of the symptom onset (group 1) and 57 received standard medical treatment at the symptom onset (group 2). Periprocedural complications were analyzed in group 1 to evaluate the safety of early CAS. Clinical effects were analyzed by evaluating National Institutes of Health Stroke Scale (NIHSS) score as well as modified Ranking Scale (mRS) score of pre- and post-treatment in 2 groups. RESULTS: There was no significant difference in pre-treatment NIHSS score between the 2 groups (8.52 ± 2.46 and 7.84 ± 2.64, p = 0.15). However, group 1 had lower post-treatment NIHSS score as compared to group 2 (3.03 ± 1.44 and 3.84 ± 1.73, p = 0.006). In both groups, NIHSS score after treatment was significantly reduced (p < 0.05). Treatment effect in group 1 was larger compared to group 2 (-5.49 ± 2.12 and -4.00 ± 1.98, p < 0.05). Before the treatment, both groups had similar patient numbers with mRS score ≤2; however, after 30 days of surgery, group 1 had more number of patients with mRS score ≤2 than group 2. CONCLUSION: This study suggested that early CAS for CWI can be performed without significant risk. More importantly, early CAS for CWI can improve the prognosis.


Assuntos
Estenose das Carótidas/complicações , Revascularização Cerebral/métodos , Idoso , Artérias Carótidas/cirurgia , Infarto Cerebral/etiologia , Infarto Cerebral/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Stents , Resultado do Tratamento
7.
Angew Chem Int Ed Engl ; 55(12): 3992-6, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26889652

RESUMO

Lithium-sulfur batteries are regarded as promising candidates for energy storage devices owing to their high theoretical energy density. The practical application is hindered, however, by low sulfur utilization and unsatisfactory capacity retention. Herein, we present a strategy for configuration of the sulfur cathode, which is composed of an integrated carbon/sulfur/carbon sandwich structure on polypropylene separator that is produced using the simple doctor-blade technique. The integrated electrode exhibits excellent flexibility and high mechanical strength. The upper and bottom carbon layers of the sandwich-structured electrode not only work as double current collectors, which effectively improve the conductivity of the electrode, but also serve as good barriers to suppress the diffusion of the polysulfide and buffer the volume expansion of the active materials, leading to suppression of the shuttle effect and low self-discharge behavior.

8.
ACS Appl Mater Interfaces ; 7(13): 7066-72, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25804889

RESUMO

Nitrogen-doped crumpled graphene (NCG) is successfully synthesized via vapor phase deposition of polypyrrole onto graphene aerogel followed by thermal treatment. The NCG was explored as an electrocatalyst for the oxygen reduction reaction, showing comparable electrocatalytic performance with the commercial Pt/C in alkaline membrane exchange fuel cells because of the well-regulated nitrogen doping and the robust micro-3D crumpled porous nanostructure.

9.
ACS Nano ; 8(10): 10920-30, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25290080

RESUMO

Although much progress has been made to develop high-performance lithium-sulfur batteries (LSBs), the reported physical or chemical routes to sulfur cathode materials are often multistep/complex and even involve environmentally hazardous reagents, and hence are infeasible for mass production. Here, we report a simple ball-milling technique to combine both the physical and chemical routes into a one-step process for low-cost, scalable, and eco-friendly production of graphene nanoplatelets (GnPs) edge-functionalized with sulfur (S-GnPs) as highly efficient LSB cathode materials of practical significance. LSBs based on the S-GnP cathode materials, produced by ball-milling 70 wt % sulfur and 30 wt % graphite, delivered a high initial reversible capacity of 1265.3 mAh g(-1) at 0.1 C in the voltage range of 1.5-3.0 V with an excellent rate capability, followed by a high reversible capacity of 966.1 mAh g(-1) at 2 C with a low capacity decay rate of 0.099% per cycle over 500 cycles, outperformed the current state-of-the-art cathode materials for LSBs. The observed excellent electrochemical performance can be attributed to a 3D "sandwich-like" structure of S-GnPs with an enhanced ionic conductivity and lithium insertion/extraction capacity during the discharge-charge process. Furthermore, a low-cost porous carbon paper pyrolyzed from common filter paper was inserted between the 0.7S-0.3GnP electrode and porous polypropylene film separator to reduce/eliminate the dissolution of physically adsorbed polysulfide into the electrolyte and subsequent cross-deposition on the anode, leading to further improved capacity and cycling stability.

10.
Sci Rep ; 4: 6095, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-25168783

RESUMO

Nano-Germanium/polypyrrole composite has been synthesized by chemical reduction method in aqueous solution. The Ge nanoparticles were directly coated on the surface of the polypyrrole. The morphology and structural properties of samples were determined by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Thermogravimetric analysis was carried out to determine the polypyrrole content. The electrochemical properties of the samples have been investigated and their suitability as anode materials for the lithium-ion battery was examined. The discharge capacity of the Ge nanoparticles calculated in the Ge-polypyrrole composite is 1014 mAh g(-1) after 50 cycles at 0.2 C rate, which is much higher than that of pristine germanium (439 mAh g(-1)). The composite also demonstrates high specific discharge capacities at different current rates (1318, 1032, 661, and 460 mAh g(-1) at 0.5, 1.0, 2.0, and 4.0 C, respectively). The superior electrochemical performance of Ge-polypyrrole composite could be attributed to the polypyrrole core, which provides an efficient transport pathway for electrons. SEM images of the electrodes have demonstrated that polypyrrole can also act as a conductive binder and alleviate the pulverization of electrode caused by the huge volume changes of the nanosized germanium particles during Li(+) intercalation/de-intercalation.

11.
Dalton Trans ; 40(48): 12801-7, 2011 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-21637877

RESUMO

A tin nanoparticle/polypyrrole (nano-Sn/PPy) composite was prepared by chemically reducing and coating Sn nanoparticles onto the PPy surface. The composite shows a much higher surface area than the pure nano-Sn reference sample, due to the porous higher surface area of PPy and the much smaller size of Sn in the nano-Sn/PPy composite than in the pure tin nanoparticle sample. Poly(vinylidene fluoride) (PVDF) and sodium carboxymethyl cellulose (CMC) were also used as binders, and the electrochemical performance was investigated. The electrochemical results show that both the capacity retention and the rate capability are in the same order of nano-Sn/PPy-CMC > nano-Sn/PPy-PVDF > nano-Sn-CMC > nano-Sn-PVDF. Scanning electronic microscopy (SEM) and electrochemical impedance spectroscopy (EIS) results show that CMC can prevent the formation of cracks in electrodes caused by the big volume changes during the charge-discharge process, and the PPy in the composite can provide a conducting matrix and alleviate the agglomeration of Sn nanoparticles. The present results indicate that the nano-Sn/PPy composite could be suitable for the next generation of anode materials with relatively good capacity retention and rate capability.

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