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1.
Small ; 19(34): e2301640, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37093205

RESUMO

Highly active bifunctional electrocatalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) have always been the key factors to affect the performance of zinc-air batteries. However, integrating the independent reaction sites of ORR and OER in a catalyst remains a major challenge. Herein, a collaborative strategy based on defect induction and doping is proposed to prepare the strain-regulated Pt-NiO@Ni sub-micron particles (Pt-NiO@Ni SP). Benefiting from the synergistic effect of tensile strain and Pt-doped, the metallic Ni-based sub-micron particles with tensile strain as the catalyst carriers can effectively optimize the electronic distribution of atomic structures in Pt and NiO on the surface of particles, leading to reduce the energy barrier of intermediates for ORR and OER. Consequently, the Pt-NiO@Ni SP exhibits outstanding bifunctional catalytic activity with the ΔE index of 0.65 V under a low Pt loading, outperforming that of the benchmark Pt/C+IrO2 catalysts (0.76 V). Impressively, the Pt-NiO@Ni SP-based liquid zinc-air battery develops a high open-circuit potential (1.47 V), excellent energy density (188.2 mW cm-2 ), and favorable cyclic charge-discharge cycling durability (200 h at 20 mA cm-2 ). This work provides an innovative avenue for the rational construction of highly active bifunctional electrocatalysts for practical applications.

2.
BMC Neurol ; 22(1): 342, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096777

RESUMO

OBJECTIVE: We analyzed the outcomes of patients suffering acute ischemic stroke (AIS) with large vessel occlusion (LVO) soon after pulmonary lobectomy. METHODS: We retrospectively reviewed the clinical records of patients who underwent pulmonary lobectomy to treat primary lung cancer. We retrieved clinical characteristics and the incidence of AIS with LVO. The clinical courses of patients who experienced AIS were reviewed. RESULTS: In 10 (0.3%) of 3406 patients, AIS with LVO developed soon (within 3 days) after pulmonary lobectomy. The lung resection site was on the left in eight patients (80%). All patients underwent thrombectomy and achieved complete recanalization (Thrombolysis in Cerebral Infarction [TICI] 3). The average time between symptom onset and recanalization was 165.5 min. Nine (90%) patients exhibited favorable outcomes (modified Rankin scale [mRS] score ≤ 2) at the 3-month follow-up. CONCLUSION: Endovascular therapy effectively treats AIS with LVO that develops after lung surgery, and direct aspiration is a promising strategy. A large, multicenter study is warranted to further confirm these findings.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Pulmão , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos
3.
CNS Neurosci Ther ; 30(7): e14832, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39009504

RESUMO

CONTEXT: In-stent restenosis (ISR) can lead to blood flow obstruction, insufficient blood supply to the brain, and may even result in serious complications such as stroke. Endothelial cell hyperproliferation and thrombosis are the primary etiologies, frequently resulting in alterations in intravascular metabolism. However, the metabolic changes related to this process are still undermined. OBJECTIVE: We tried to characterize the serum metabolome of patients with ISR and those with non-restenosis (NR) using metabolomics and lipidomics, exploring the key metabolic pathways of this pathological phenomenon. RESULTS: We observed that the cysteine and methionine pathways, which are associated with cell growth and oxidative homeostasis, showed the greatest increase in the ISR group compared to the NR group. Within this pathway, the levels of N-formyl-l-methionine and L-methionine significantly increased in the ISR group, along with elevated levels of downstream metabolites such as 2-ketobutyric acid, pyruvate, and taurocholate. Additionally, an increase in phosphatidylcholine (PC) and phosphatidylserine (PS), as well as a decrease in triacylglycerol in the ISR group, indicated active lipid metabolism in these patients, which could be a significant factor contributing to the recurrence of blood clots after stent placement. Importantly, phenol sulfate and PS(38:4) were identified as potential biomarkers for distinguishing ISR, with an area under the curve of more than 0.85. CONCLUSIONS: Our study revealed significant metabolic alterations in patients with ISR, particularly in the cysteine and methionine pathways, with phenol sulfate and PS(38:4) showing promise for ISR identification.


Assuntos
Metaboloma , Stents , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Metaboloma/fisiologia , Idoso , Stents/efeitos adversos , Lipidômica/métodos , Metabolismo dos Lipídeos/fisiologia , Reestenose Coronária/metabolismo , Metabolômica/métodos
4.
Langmuir ; 29(5): 1676-82, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23297795

RESUMO

The charging characteristics of micrometer sized aqueous droplets have attracted more and more attentions due to the development of the microfluidics technology since the electrophoretic motion of a charged droplet can be used as the droplet actuation method. This work proposed a novel method of investigating the charging characteristics of micrometer sized aqueous droplets based on parallel plate capacitor model. With this method, the effects of the electric field strength, electrolyte concentration, and ion species on the charging characteristics of the aqueous droplets was investigated. Experimental results showed that the charging characteristics of micrometer sized droplets can be investigated by this method.

5.
Risk Anal ; 33(7): 1293-311, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23106231

RESUMO

This article proposes a methodology for the application of Bayesian networks in conducting quantitative risk assessment of operations in offshore oil and gas industry. The method involves translating a flow chart of operations into the Bayesian network directly. The proposed methodology consists of five steps. First, the flow chart is translated into a Bayesian network. Second, the influencing factors of the network nodes are classified. Third, the Bayesian network for each factor is established. Fourth, the entire Bayesian network model is established. Lastly, the Bayesian network model is analyzed. Subsequently, five categories of influencing factors, namely, human, hardware, software, mechanical, and hydraulic, are modeled and then added to the main Bayesian network. The methodology is demonstrated through the evaluation of a case study that shows the probability of failure on demand in closing subsea ram blowout preventer operations. The results show that mechanical and hydraulic factors have the most important effects on operation safety. Software and hardware factors have almost no influence, whereas human factors are in between. The results of the sensitivity analysis agree with the findings of the quantitative analysis. The three-axiom-based analysis partially validates the correctness and rationality of the proposed Bayesian network model.

7.
Transl Stroke Res ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049671

RESUMO

The roles of cerebral structures distal to isolated thalamic infarcts in cognitive deficits remain unclear. We aimed to identify the in vivo microstructural characteristics of remote gray matter (GM) and thalamic pathways and elucidate their roles across cognitive domains. Patients with isolated ischemic thalamic stroke and healthy controls underwent neuropsychological assessment and magnetic resonance imaging. Neurite orientation dispersion and density imaging (NODDI) was modeled to derive the intracellular volume fraction (VFic) and orientation dispersion index. Fiber density (FD) was determined by constrained spherical deconvolution, and tensor-derived fractional anisotropy (FA) was calculated. Voxel-wise GM analysis and thalamic pathway tractography were performed. Twenty-six patients and 26 healthy controls were included. Patients exhibited reduced VFic in remote GM regions, including ipsilesional insular and temporal subregions. The microstructural metrics VFic, FD, and FA within ipsilesional thalamic pathways decreased (false discovery rate [FDR]-p < 0.05). Noteworthy associations emerged as VFic within insular cortices (ρ = -0.791 to -0.630; FDR-p < 0.05) and FD in tracts connecting the thalamus and insula (ρ = 0.830 to 0.971; FDR-p < 0.001) were closely associated with executive function. The VFic in Brodmann area 52 (ρ = -0.839; FDR-p = 0.005) and FA within its thalamic pathway (ρ = -0.799; FDR-p = 0.003) correlated with total auditory memory scores. In conclusion, NODDI revealed neurite loss in remote normal-appearing GM regions and ipsilesional thalamic pathways in thalamic stroke. Reduced cortical dendritic density and axonal density of thalamocortical tracts in specific subregions were associated with improved cognitive functions. Subacute microstructural alterations beyond focal thalamic infarcts might reflect beneficial remodeling indicating post-stroke plasticity.

8.
Stroke Vasc Neurol ; 7(5): 462-464, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35354663

RESUMO

Vertebral artery stump syndrome (VASS) is a rare disease associated with a posterior circulation stroke after vertebral artery origin occlusion. We have herein presented a case of VASS that was effectively treated with endovascular intervention using retrograde recanalisation and the mechanism of VASS in our patient was thought to be a thrombus formed by stagnating flow.


Assuntos
Arteriopatias Oclusivas , Síndrome Medular Lateral , Acidente Vascular Cerebral , Humanos , Artéria Vertebral/diagnóstico por imagem
9.
Front Neurol ; 13: 846348, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401411

RESUMO

Objective: Brain atrophy is an important imaging characteristic of cerebral small vascular disease (CSVD). Our study explores the linear measurement application on CT images of CSVD patients and develops a fully automatic brain atrophy classification model. The second aim was to compare it with the end-to-end Convolutional Neural Networks (CNNs) model. Methods: A total of 385 subjects such as 107 no-atrophy brain, 185 mild atrophy, and 93 severe atrophy were collected and randomly separated into training set (n = 308) and test set (n = 77). Key slices for linear measurement were manually identified and used to annotate nine linear measurements and a binary classification of cerebral sulci widening. A linear-measurement-based pipeline (2D model) was constructed for two-types (existence/non-existence brain atrophy) or three-types classification (no/mild atrophy/severe atrophy). For comparison, an end-to-end CNN model (3D-deep learning model) for brain atrophy classification was also developed. Furthermore, age and gender were integrated to the 2D and 3D models. The sensitivity, specificity, accuracy, average F1 score, receiver operating characteristics (ROC) curves for two-type classification and weighed kappa for three-type classification of the two models were compared. Results: Automated measurement of linear measurements and cerebral sulci widening achieved moderate to almost perfect agreement with manual annotation. In two-type atrophy classification, area under the curves (AUCs) of the 2D model and 3D model were 0.953 and 0.941 with no significant difference (p = 0.250). The Weighted kappa of the 2D model and 3D model were 0.727 and 0.607 according to standard classification they displayed, mild atrophy and severe atrophy, respectively. Applying patient age and gender information improved classification performances of both 2D and 3D models in two-type and three-type classification of brain atrophy. Conclusion: We provide a model composed of different modules that can classify CSVD-related brain atrophy on CT images automatically, using linear measurement. It has similar performance and better interpretability than the end-to-end CNNs model and may prove advantageous in the clinical setting.

10.
J Int Med Res ; 48(10): 300060520965807, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33103503

RESUMO

It is unclear whether cilostazol instead of aspirin in combination with clopidogrel could prevent in-stent thrombosis in patients with a history of gout undergoing vertebral artery origin stenting. Three men (age range, 58-74 years) were diagnosed with acute ischaemic stroke or transient ischaemic attack. Vertebral artery origin stenosis was visible by computed tomographic angiography or digital subtraction angiography. Four bare metal stents were placed in the vertebral artery origin. The patients were administered 100 mg cilostazol orally twice a day and 75 mg clopidogrel orally once a day perioperatively and 100 mg cilostazol orally twice day was administered indefinitely after 3 months. No in-stent stenosis was observed in all of these patients during a follow-up period up to 19 months. Cilostazol plus clopidogrel has the potential to become an alternative to standard dual antiplatelet therapy in vertebral artery origin stenting. A high-quality clinical trial is needed to verify these preliminary findings.


Assuntos
Isquemia Encefálica , Gota , Acidente Vascular Cerebral , Idoso , Isquemia Encefálica/tratamento farmacológico , Cilostazol/uso terapêutico , Clopidogrel/uso terapêutico , Constrição Patológica , Quimioterapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Stents , Acidente Vascular Cerebral/tratamento farmacológico , Tetrazóis/uso terapêutico , Ticlopidina/uso terapêutico , Resultado do Tratamento , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/cirurgia
11.
Transl Stroke Res ; 11(5): 890-899, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32043214

RESUMO

Data on the association between hemoglobin (Hb) levels and poststroke cognitive function are limited. We investigated the relationship between Hb concentrations at admission and poststroke cognitive function using a multicenter database. In total, 1081 patients were recruited from seven Chinese medical centers within 6 months after experiencing ischemic stroke. Cognitive status was evaluated with a series of brief neuropsychological tests. A subgroup of 439 patients from a single center was followed up for 4-6 years and was eventually reassessed with a cognitive test. The association between Hb and cognitive impairment was analyzed by multivariable Tobit regression and logistic regression. The mean age of the 920 eligible participants at study entry was 42.5 years; 311 (34%) were women, and all participants were Chinese nationals who lived locally. After adjustment for multiple covariables, Hb levels at admission remained positively associated with poststroke Mini-Mental State Examination (MMSE) scores, with a 0.37-point increase in the MMSE score for every 1-standard-deviation increase in the Hb level. Moreover, an optimal Hb level above 15.0 g/dl was proposed for preventing or alleviating the development of poststroke cognitive impairment in men. After 4-6 years of rehabilitation, the baseline Hb still correlated with MMSE scores. A significant interaction was found between baseline Hb and change in MMSE scores over time, with higher baseline Hb levels predicting faster recovery of global cognitive performance (ß, 0.21; 95% confidence interval, 0.03-0.39).These findings warrant further study of anemia as a risk factor for poststroke cognitive impairment.


Assuntos
Isquemia Encefálica/sangue , Disfunção Cognitiva/etiologia , Hemoglobinas/metabolismo , AVC Isquêmico/sangue , Adulto , Idoso , Disfunção Cognitiva/sangue , Feminino , Hospitalização/estatística & dados numéricos , Humanos , AVC Isquêmico/complicações , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
Nanoscale ; 11(47): 22734-22742, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31763653

RESUMO

Hydrogen production by water electrolysis is a common strategy for the development of renewable energy. However, meeting the industrial requirement for high efficiency and low cost is difficult to achieve with the existing methods. Herein, a novel and simple synthesis route for a dendritic self-supported electrode consisting of oxygen vacancy-rich NiO embedded within ultrathin 2D/3D nanostructures (NiO-Vo@2D/3D NS@DSE) for overall water splitting is developed for the first time. Based on the simple compound synthesis by jet electrodeposition and in situ acid etching, 2D nanosheets adhering uniformly to 3D nanospheres are successfully obtained on the dendritic self-supported skeleton surface. The experiments and density functional calculations illustrate that this electrode integrates the advantages including numerous active sites, intrinsic catalytic activity, good electrical conductivity, and outstanding reaction kinetic performance. Moreover, NiO-Vo@2D/3D NS@DSE shows excellent oxygen evolution reaction and hydrogen evolution reaction activities in 1 M KOH with overpotentials of 230 and 51 mV at 10 mA cm-2, respectively. Additionally, the electrode, as an alkali-electrolyzer, displays a potential of 1.51 V at 10 mA cm-2 with favorable stability that is superior to that of IrO2@nickel foam (NF)//Pt/C@NF (1.62 V). Surprisingly, the cost of NiO-Vo@2D/3D NS@DSE is ≈1/120 of the price of noble electrocatalysts with the same mass. This research opens up a new pathway for the design of bifunctional electrocatalysts.

13.
Front Neurol ; 9: 89, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29535675

RESUMO

In the dual-route language model, the dorsal pathway is known for sound-to-motor mapping, but the role of the ventral stream is controversial. With the goal of enhancing our understanding of language models, this study investigated the diffusion characteristics of candidate tracts in aphasic patients. We evaluated 14 subacute aphasic patients post-stroke and 11 healthy controls with language assessment and diffusion magnetic resonance imaging. Voxel-based lesion-symptom mapping found multiple linguistic associations for the ventral stream, while automated fiber quantification (AFQ) showed, via reduced fractional anisotropy (FA) and axial diffusivity with increased radial diffusivity (all corrected p < 0.05), that the integrity of both the left dorsal and ventral streams was compromised. The average diffusion metrics of each fascicle provided by AFQ also confirmed that voxels with significant FA-language correlations were located in the ventral tracts, including the left inferior fronto-occipital fascicle (IFOF) (comprehension: r = 0.839, p = 0.001; repetition: r = 0.845, p = 0.001; naming: r = 0.813, p = 0.002; aphasia quotient: r = 0.847, p = 0.001) and uncinate fascicle (naming: r = 0.948, p = 0.001). Furthermore, point-wise AFQ revealed that the segment of the left IFOF with the strongest correlations was its narrow stem. The temporal segment of the left inferior longitudinal fascicle was also found to correlate significantly with comprehension (r = 0.663, p = 0.03) and repetition (r = 0.742, p = 0.009). This preliminary study suggests that white matter integrity analysis of the ventral stream may have the potential to reveal aphasic severity and guide individualized rehabilitation. The left IFOF, specifically its narrow stem segment, associates with multiple aspects of language, indicating an important role in semantic processing and multimodal linguistic functions.

14.
PLoS One ; 11(2): e0148324, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26859390

RESUMO

BACKGROUND: Inconsistent results have been reported for hyperbaric oxygen therapy (HBO) for acute stroke. We conducted a systematic review and meta-analysis to evaluate the benefit of HBO in animal studies of middle cerebral artery occlusion (MCAO). METHODS: A systematic search of the literature published prior to September 2015 was performed using Embase, Medline (OvidSP), Web of Science and PubMed. Keywords included "hyperoxia" OR "hyperbaric oxygen" OR "HBO" AND "isch(a)emia" OR "focal cerebral ischemia" OR "stroke" OR "infarct" OR "middle cerebral artery occlusion (MCAO)." The primary endpoints were the infarct size and/or neurological outcome score evaluated after HBO treatment in MCAO. Heterogeneity was analyzed using Cochrane Library's RevMan 5.3.5. RESULTS: Fifty-one studies that met the inclusion criteria were identified among the 1198 studies examined. When compared with control group data, HBO therapy resulted in infarct size reduction or improved neurological function (32% decrease in infarct size; 95% confidence interval (CI), range 28%-37%; p < 0.00001). Mortality was 18.4% in the HBO group and 26.7% in the control group (RR 0.72, 95% CI, 0.54-0.98; p = 0.03). Subgroup analysis showed that a maximal neuro-protective effect was reached when HBO was administered immediately after MCAO with an absolute atmospheric pressure (ATA) of 2.0 (50% decrease; 95% CI, 43% -57% decrease; p < 0.0001) and more than 6 hours HBO treatment (53% decrease; 95% CI, 41% -64% decrease; p = 0.0005). CONCLUSIONS: HBO had a neuro-protective effect and improved survival in animal models of MCAO, especially in animals given more than 6 hours of HBO and when given immediately after MCAO with 2.0 ATA.


Assuntos
Oxigenoterapia Hiperbárica/métodos , Infarto da Artéria Cerebral Média/terapia , Animais , Modelos Animais de Doenças
15.
PLoS One ; 9(11): e110775, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25364912

RESUMO

Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR). The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 Ω·cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 Ω·cm is obviously different from that with the electrical resistivity lower than 687 Ω·cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical discharge machining ZnO/Al2O3 ceramic.


Assuntos
Cerâmica/química , Impedância Elétrica , Eletricidade
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