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1.
Front Neurol ; 15: 1421655, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39233681

RESUMO

Background: Insulin resistance (IR) can predict the prognosis of patients suffering from cerebrovascular disorders. The triglyceride-glucose (TyG) index and triglyceride-to-high-density lipoprotein cholesterol (TG/HDL-C) ratio have been confirmed to be easy and reliable indicators of IR. However, the relationships between the TyG index or TG/HDL-C ratio and early neurological deterioration (END) after thrombolysis in patients with acute ischemic stroke (AIS) are uncertain. Methods: A retrospective analysis of 1,187 patients diagnosed with AIS who underwent intravenous thrombolysis between January 2018 and February 2024 was performed. Post-thrombolysis END was defined as an increase in the National Institutes of Health Stroke Scale (NIHSS) score of ≥4 within 24 h after thrombolysis. Logistic regression analysis was performed to explore the relationships of the TyG index and TG/HDL-C ratio with post-thrombolysis END. Receiver operating characteristic (ROC) analysis was used to assess the ability of the TyG index and TG/HDL-C ratio to discriminate post-thrombolysis END. Results: Among the 1,187 recruited patients, 179 (15.08%) were diagnosed with post-thrombolysis END, and 1,008 (84.92%) were diagnosed with non-END. A binary logistic regression model indicated that the TyG index (odds ratio [OR], 2.015; 95% confidence interval [CI] 1.964-2.414, p = 0.015) and TG/HDL-C ratio (OR, 1.542; 95% CI, 1.160-2.049, p = 0.004) were independent factors for post-thrombolysis END. The area under the curve (AUC) values for the TyG index, TG/HDL-C ratio, and TyG index combined with the TG/HDL-C ratio for post-thrombolysis END were 0.704, 0.674, and 0.755, respectively. Conclusion: This study indicates that the TyG index and TG/HDL-C ratio can be used as prognostic factors to predict post-thrombolysis END.

3.
Front Bioeng Biotechnol ; 11: 1249775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576992

RESUMO

Hyperthermia therapy is a hotspot because of its minimally invasive treatment process and strong targeting effect. Herein, a synergistic magnetic and photothermal therapeutic nanoplatform is rationally constructed. The well-dispersive mSiO2-SmCox nanoparticles (NPs) were synthesized through a one-step procedure with the regulated theoretical molar ratio of Sm/Co among 1:1, 1:2, and 1:4 for controlling the dispersion and magnetism properties of SmCox NPs in situ growth in the pore structure of mesoporous SiO2 (mSiO2), where mSiO2 with diverse porous structures and high specific surface areas serving for locating the permanent magnetic SmCox NPs. The mSiO2-SmCox (Sm/Co = 1:2) NPs with highly dispersed and uniform morphology has an average diameter of ∼73.08 nm. The photothermal conversion efficiency of mSiO2-SmCox (Sm/Co = 1:2) NPs was determined to be nearly 41%. The further in vitro and in vivo anti-tumor evaluation of mSiO2-SmCox (Sm/Co = 1:2) NPs present promising potentials for hyperthermia-induced tumor therapy due to magnetic and photothermal effects.

4.
Angew Chem Int Ed Engl ; 62(45): e202307086, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37475578

RESUMO

Synthesis of formate from hydrogenation of carbon dioxide (CO2 ) is an atom-economic reaction but is confronted with challenges in developing high-performance non-precious metal catalysts for application of the process. Herein, we report a highly durable edge-rich molybdenum disulfide (MoS2 ) catalyst for CO2 hydrogenation to formate at 200 °C, which delivers a high selectivity of over 99 % with a superior turnover frequency of 780.7 h-1 surpassing those of previously reported non-precious metal catalysts. Multiple experimental characterization techniques combined with theoretical calculations reveal that sulfur vacancies at MoS2 edges are the active sites and the selective production of formate is enabled via a completely new water-mediated hydrogenation mechanism, in which surface OH* and H* species in dynamic equilibrium with water serve as moderate hydrogenating agents for CO2 with residual O* reduced by hydrogen. This study provides a new route for developing low-cost high-performance catalysts for CO2 hydrogenation to formate.

5.
Curr Neurovasc Res ; 18(4): 435-445, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34758715

RESUMO

OBJECTIVE: The objective of this study is to determine whether the administration of intravenous alteplase would be beneficial or futile to patients with acute ischemic stroke caused by large vessel occlusion (LVO) before endovascular treatment (EVT) and determine the relationship between Hounsfield units (HU) in non-contrast computed tomography (NCCT) and recanalization by alteplase. METHODS: We performed a retrospective analysis of patients with acute ischemic stroke caused by LVO who received intravenous thrombolysis (IVT) or followed by EVT at our center during November 2016 and October 2020. The clinical characteristics and imaging features of patients who achieved recanalization after IVT, and those who did not, were compared. RESULTS: Forty-three eligible patients were enrolled; 12 achieved recanalization by IVT. Baseline clinical characteristics did not differ between patients of the recanalization and non-recanalization groups. HU in the NCCT were estimated and statistically significant maximum and mean values of the ipsilateral middle cerebral artery (MCA) were found between the groups (P< 0.05). The results hint that patients in the non-recanalization group have a higher rHU and δHU value of the ipsilateral MCA compared with recanalization group (P< 0.05). With regards to the receiver operator characteristic (ROC) curve, we demonstrated that a high HU value of the ipsilateral MCA could be a predictor for non-recanalization by IVT. CONCLUSION: Patients suffering LVO stroke are less likely to obtain recanalization by IVT with a high HU value of the ipsilateral MCA. It is feasible to screen patients with LVO using HU for direct EVT.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Computadores , Fibrinolíticos/uso terapêutico , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
6.
Intern Emerg Med ; 16(4): 925-932, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33111164

RESUMO

We aimed at establishing a new COVID-19 risk scores, serving as a guide for rapidly screening the COVID-19 patients in order to reduce the risk of COVID-19 hospital-related transmission. As the COVID-19 disease is breaking out across the world, hospital-related transmission is one of the main factors accountable for the spread of COVID-19. For COVID-19 prevention it is urgent to establish a fast and efficient screening strategy for the COVID-19 patients. We analyzed 335 patients (including 124 patients with COVID-19). Five significant clinical attributes were selected as the components for establishing a COVID-19 risk score system, and every attribute was assigned a specific score according to their respective odds ratio values. We also compared three different screening schemes (Scheme I: temperature higher than 37.2 °C on admission, Scheme II: exposure to a source of transmission within 14 days in addition to fever, Scheme III: our new COVID-19 risk score) in terms of their respective receiver operating characteristic (ROC) curves, so as to evaluate their respective screening effectiveness. Five significant risk factors, which were exposed to a source of transmission (9 points), cluster onset (6 points), history of fever or temperature higher than 37.2 °C on admission (4 points), cough (1 point) and other atypical symptoms (1 point), were ultimately selected from many candidates to construct the new rapid COVID-19 screening program. Based on the screening scheme, the patients were quickly divided into three subgroups according to their respective COVID-19 risk scores: low risk (≤ 6 points, risk < 10%), medium risk (7-13 points) and high risk (≥ 14 points, risk > 80%). When the score of 10 points was selected as a cut-off point for differentiating the patients with COVID-19 from all of the other patients, the sensitivity was 93.6%, with a specificity of 86.3%. The area under the ROC curve (AUC) of COVID-19 risk score system was 0.96 (P = 0.000), much higher than the AUCs of Scheme I (0.56, P = 0.000) and Scheme II (0.85, P = 0.000), respectively. Our COVID-19 risk score system can help the clinicians effectively and rapidly identify and differentiate the patients with COVID-19 infections, to be mainly used in those areas where COVID-19 still exhibits epidemiological characteristics.


Assuntos
COVID-19/diagnóstico , Serviço Hospitalar de Emergência , Programas de Rastreamento , Adulto , COVID-19/complicações , COVID-19/transmissão , China , Feminino , Febre/diagnóstico , Febre/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Avaliação de Sintomas
7.
Dalton Trans ; 49(13): 4030-4033, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32133475

RESUMO

A synergistic effect between dimethylglyoxime (to stabilize the Ti-O ribbon) and nonlinear dicarboxylate ligands (to bend the Ti-O ribbon) has been developed to form a series of planar chiral titanium-oxo clusters with high solution stability. The charality of the obtained clusters has been studied by X-ray structural and CD spectroscopy analysis.

8.
Dalton Trans ; 48(27): 9916-9919, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31199422

RESUMO

Through ligand-directed assembly of trapezoidal {Ti5} building blocks stabilized by dimethylglyoxime, eight titanium-oxo molecular clusters with a sandwich or square planar type structures were successfully constructed, including the first success on the combination of porphyrin and titanium-oxo clusters.

9.
Phys Chem Chem Phys ; 20(25): 17471-17476, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29911711

RESUMO

Graphitic carbon nitride (g-C3N4) is an actively investigated metal-free photocatalyst for solar energy conversion. However, primary g-C3N4 usually exhibits limited utilization of visible light and fast combination of photoexcited charge carriers, resulting in low photocatalytic H2 evolution activity. Defect-modified g-C3N4 shows much enhanced photocatalytic H2 evolution activity owing to extended light absorption as well as efficient charge separation and transfer. Here, the photocatalyst simultaneously containing nitrogen vacancies and O-doping is successfully developed by using a two-step post-synthetic strategy for photocatalytic H2 evolution, resulting in a greatly-boosted H2 evolution activity (1.69 × 103 µmol g-1 h-1) compared with that of pristine g-C3N4 (1.12 × 102 µmol g-1 h-1). It is believed that the newly developed double-defect strategy may open an avenue toward obtaining molecular level comprehension of the function of a catalyst in photocatalytic H2 evolution and can be extended to the modification of other semiconductors.

10.
ACS Nano ; 12(6): 5333-5340, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29808991

RESUMO

BIF-20, a zeolite-like porous boron imidazolate framework with high density of exposed B-H bonding, is combined with graphitic carbon nitride (g-C3N4) nanosheets via a facile electrostatic self-assembly approach under room temperature, forming an elegant composite BIF-20@g-C3N4 nanosheet. The as-constructed composite preferably captures CO2 and further photoreduces CO2 in high efficiency. The photogenerated excitations from the carbon nitride nanosheet can directionally migrate to B-H bonding, which effectively suppresses electron-hole pair recombination and thus greatly improves the photocatalytic ability. Compared to the g-C3N4 nanosheet, the BIF-20@g-C3N4 nanosheet composite displayed a much-enhanced photocatalytic CO2 reduction activity, which is equal to 9.7-fold enhancements in the CH4 evolution rate (15.524 µmol g-1 h-1) and 9.85-fold improvements in CO generation rate (53.869 µmol g-1 h-1). Density functional theory simulations further prove that the presence of B-H bonding in the composite is favorable for CO2 adhesion and activation in the reaction process. Thus, we believe that the implantation of functional active sites into the porous matrix provides important insights for preparation of a highly efficient photocatalyst.

11.
Nanoscale ; 10(5): 2649-2657, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29355860

RESUMO

Interface modification is an effective and promising route for developing functional electrocatalysts. However, researchers have not created a reliable method to optimize the interfaces of components existing in electrocatalysts, although it is very crucial for the technological development of high-performance electrodes. Here, we develop a strategy aiming at the in situ anchorage of Co9S8 nanoparticles into a nitrogen (N), sulfur (S) co-implanted three-dimensional carbon matrix (Co9S8@NSCM) as a highly active and durable nonprecious metal electrocatalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in alkaline medium. This strategy offers an opportunity to optimize the interface interaction and affords high activity for the ORR and OER in terms of low overpotentials and high current intensities. In addition, by confining Co9S8 nanoparticles into a N,S-doped carbon matrix, corrosion and aggregation can be effectively prevented, and thus the catalyst exhibits nearly unfading ORR catalytic performance after 100 000 s testing, a low discharge-charge voltage gap (0.81 V) and a long cycle life (up to 840 cycles) in Zn-air batteries. The present work highlights potentially powerful interface engineering for designing multi-component heterostructures with advanced performances in oxygen electrochemistry and related energy conversion.

12.
Dalton Trans ; 46(31): 10202-10204, 2017 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-28745356

RESUMO

An anionic Cd(ii) boron imidazolate framework (BIF-82) with gra topology has been synthesized by the targeted assembly of Cd(ii), the 1,3,5-benzenetricarboxylate ligand and the tetradentate boron imidazolate ligand, which shows reversible structural transformation, and it can encapsulate Ag nanoparticles into its structure for further sensing of cysteine.

13.
Chem Commun (Camb) ; 52(17): 3552-5, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26843436

RESUMO

Reported here is a versatile method capable of generating pore space partition in zeolitic boron imidazolate frameworks (BIFs), which is based on the coexistence of presynthesized boron imidazolate complexes and charge balancing carboxylate ligands. Using this method, boron imidazolate complexes are used to form zeolitic nets, while the carboxylate serves to partition large channel spaces into multiple domains. The generality of this method is shown by two distinct boron imidazolate frameworks mimicking GIS (BIF-41) and ABW (BIF-42) zeotype topologies. BIF-41 shows high selectivity sorption of CO2 over N2.


Assuntos
Boro/química , Dióxido de Carbono/química , Imidazóis/química , Zeolitas/química
14.
Biosens Bioelectron ; 25(2): 362-7, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19692225

RESUMO

A simple biosensor for hydrogen peroxide (H(2)O(2)) and glucose was fabricated by incorporating gold nanoparticles (GNPs) onto a cuttlebone-derived matrix substrate (CDMS). Such a three-dimensional chamber-like structure naturally bears abundant amino groups for the direct immobilization of GNPs without a series of modifications. And preferably, the framework endows CDMS with a very high surface area for the attachment of GNPs, resulting in effective optical signal transduction and improved sensitivity of the detection system. The principle behind this biosensor is that the localized surface plasmon resonance (LSPR) of the immobilized GNPs changes with the enlargement of GNPs by H(2)O(2)-mediated chemical reduction of chloroauric acid. Using this approach, we demonstrate the proof of an optical biosensor to quantify the concentration of H(2)O(2) as well as glucose. UV-vis absorption spectra were recorded to obtain quantitative information about the H(2)O(2) or glucose concentration. The detection range of our biosensor to H(2)O(2) concentration was from 2 x 10(-6) to 1.5 x 10(-4)M, while the linear response range of glucose concentration was from 5 x 10(-6) to 5 x 10(-5)M. Inspiringly and interestingly, the growth of GNPs on CDMS gives rise to color changes, this phenomenon shows that the rapid detection by our sensor has the superiority in visual detection to a certian extent, which has been a potential application in qualitative or semiquantitative analysis for medicine and biotechnology.


Assuntos
Técnicas Biossensoriais/instrumentação , Matriz Óssea/química , Decapodiformes/química , Glucose/análise , Peróxido de Hidrogênio/análise , Ressonância de Plasmônio de Superfície/instrumentação , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Ouro/química , Nanopartículas/química , Nanotecnologia/instrumentação
15.
Colloids Surf B Biointerfaces ; 68(2): 231-7, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19095422

RESUMO

Biologically derived materials provide a rich variety of approaches toward new functional materials because of their fascinating structures and environment-friendly features, which is currently a topic of research interest. In this paper, we show that the cuttlebone-derived organic matrix (CDOM) is an excellent scaffold for the one-step synthesis and assembly of silver nanoparticles (AgNPs), which can be further used as substrate for surface-enhanced Raman scattering (SERS). Formation of AgNPs-CDOM composite was accomplished by the reaction of CDOM with AgNO(3) and NH(3).H(2)O solution at 80 degrees C without using any other stabilizer and reducing agents. UV-vis spectra and TEM were utilized to characterize the AgNPs and investigate their formation process. Results demonstrate that the size and distribution of AgNPs can be partly regulated by changing incubation time; the concentration of NH(3).H(2)O is critical to the formation rate of AgNPs. As a proof of principle, we show that the AgNPs-CDOM composite can be employed in trace analysis using SERS.


Assuntos
Osso e Ossos/química , Decapodiformes/química , Nanopartículas Metálicas/química , Nanocompostos/química , Compostos Orgânicos/química , Prata/química , Alicerces Teciduais , Animais , Osso e Ossos/ultraestrutura , Cinética , Nanopartículas Metálicas/ultraestrutura , Espectrofotometria Ultravioleta , Análise Espectral Raman , Propriedades de Superfície , Fatores de Tempo
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