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1.
Front Psychol ; 14: 1218959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519396

RESUMO

Introduction: Students who use spherical video-based virtual reality (SVVR) teaching materials for learning are able to gain more self-regulated, explorative, and immersive experiences in a virtual environment. Using SVVR teaching materials in art courses can present diverse and unique teaching effects, while also leading to the emergence of students' flow states. Methods: Therefore, through an art course teaching experiment, this study investigated 380 high school students and used structural equation modeling to analyze the antecedents and outcomes of students' flow state in using SVVR teaching materials. Results: The results show that in using SVVR teaching materials in art courses, more attention should be paid to the control and telepresence in the antecedents of students' flow state. Discussion: Only when they obtain better flow experiences can they have higher perceived usefulness and satisfaction with the content of the art course, as well as stronger intentions to continue using it. These results can provide a reference for the development and use of SVVR teaching materials in high school art courses.

2.
Diagnostics (Basel) ; 13(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37296704

RESUMO

BACKGROUND: Three-dimensional facial soft tissue landmark prediction is an important tool in dentistry, for which several methods have been developed in recent years, including a deep learning algorithm which relies on converting 3D models into 2D maps, which results in the loss of information and precision. METHODS: This study proposes a neural network architecture capable of directly predicting landmarks from a 3D facial soft tissue model. Firstly, the range of each organ is obtained by an object detection network. Secondly, the prediction networks obtain landmarks from the 3D models of different organs. RESULTS: The mean error of this method in local experiments is 2.62±2.39, which is lower than that in other machine learning algorithms or geometric information algorithms. Additionally, over 72% of the mean error of test data falls within ±2.5 mm, and 100% falls within 3 mm. Moreover, this method can predict 32 landmarks, which is higher than any other machine learning-based algorithm. CONCLUSIONS: According to the results, the proposed method can precisely predict a large number of 3D facial soft tissue landmarks, which gives the feasibility of directly using 3D models for prediction.

3.
Food Funct ; 14(2): 1087-1098, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36594456

RESUMO

Imatinib mesylate (IMA) belonging to the selective tyrosine kinase inhibitor family has been proven to induce cardiotoxic effects along with therapeutic strategies. Nrf2-dependent ferroptosis has been implicated in the cardiotoxicity induced by IMA. The present study was designed to investigate the protective effects of berberine hydrochloride (Ber) on cardiac injuries induced by IMA and to explore its potential mechanisms. In H9c2 cells, cell viability, the generation of reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and labile iron pool (LIP) levels were measured. In a mouse model of IMA-induced cardiomyopathy, serum biomarkers and cardiac tissues were examined. A western blot assay was performed to evaluate the expression of ferroptosis-related proteins in vitro and in vivo. Our results indicated that Ber increased cell viability and MMP and decreased cellular ROS and iron levels in comparison to the IMA group of H9c2 cells. In mice, Ber significantly improved cardiac status and attenuated the level of ferroptosis biomarkers including malonaldehyde (MDA) and iron content. Additionally, Ber downregulated the expression of transferrin receptor (TfR) and P53 and upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase-1 (NQO1), ferritin heavy chain-1 (FTH1), and glutathione peroxidase 4 (GPX4) in H9c2 cells and mice. The present data indicated that Ber has the potential to protect against IMA-induced cardiotoxicity, partly via inhibiting Nrf2-dependent ferroptosis.


Assuntos
Berberina , Ferroptose , Animais , Camundongos , Berberina/farmacologia , Biomarcadores , Cardiotoxicidade , Mesilato de Imatinib/farmacologia , Ferro/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ratos
4.
J Nutr Biochem ; 112: 109241, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36442718

RESUMO

The clinical use of 5-fluorouracil (5-FU), a potent antitumor agent, was limited by severe cardiotoxic effects. The present study was aimed to investigate the protective effects of resveratrol (Res) on 5-FU-induced cardiotoxicity and to explore its potential mechanisms.The cardiotoxicity model was intraperitoneal injection of 5-FU at the dose of 30 mg/kg for 7 consecutive days. Plasma enzymes activities, cardiac tissues were assessed after treatment with Res for 3 weeks. Ferrostatin-1 (Fer-1) was used as ferroptosis inhibitor. In H9c2 cardiomyocyte cells, cell viability, generation of reactive oxygen species (ROS), mitochondrial activity and cellular Fe2+ levels were measured. Western-blot assay was performed to evaluate the protein level of ferroptosis in vitro and in vivo. In the mice model, Res reduced 5-FU-induced cardiomyocyte injury (ferroptosis, myofibrillar loss and vacuolization). In addition, increased serum creatine kinase (CK), lactate dehydrogenase (LDH), malonaldehyde (MDA) and Fe2+ activity and decreased activities of glutathione (GSH) were observed in 5-FU group. These changes were prevented by treatment with Res. In H9c2 cardiomyocyte cells, Res increased the cell viability and attenuated cell ferroptosis as measured by DCFH-DA, TMRE and Calcein AM staining. In addition, 5-FU induced a reduction in GPX4, FTH1, Nrf2 and NQO1 and activation of TfR and P53 compared with the control group. However, Res effectively inhibited the changes in ferroptosis associated proteins in vitro and in vivo. Res possessed the cardioprotective potential against 5-FU induced cardiotoxicity. Moreover, Res attenuates 5-FU-induced cardiotoxicity via inhibiting GPX4 dependent ferroptosis.


Assuntos
Cardiotoxicidade , Ferroptose , Resveratrol , Animais , Camundongos , Cardiotoxicidade/etiologia , Ferroptose/efeitos dos fármacos , Fluoruracila/toxicidade , Glutationa , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Resveratrol/farmacologia , Ratos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/efeitos dos fármacos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo
5.
J Pharm Pharmacol ; 75(1): 49-56, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36173891

RESUMO

OBJECTIVES: Resveratrol (Res) was a naturally occurring polyphenol compound. It has various beneficial effects, including anti-inflammatory, anti-oxidant and anti-cancer effects. However, the anti-cancer activity was hindered by its low targeting and drug release performance. Thus, we synthesized transferrin-cathepsin B cleavable peptide modified mesoporous silica nanoparticle encapsulated Res (Tf-Res-MSN). METHODS: Res was encapsulated in mesoporous silica nanoparticles (MSN), which was a kind of drug carrier complex. Tf was modified to recognize the cancer cells. Cathepsin B cleavable peptide (Pep) was used to combine Res-MSN complex and Tf to construct the final product. Pep was used as linker and trigger for Res release. KEY FINDINGS: The smart nanocarriers were increased the drug release performance of Res in human breast cancer (MCF-7) cells. The physicochemical properties of Tf-Res-MSN were assessed by zeta potential, UV-Prove, diffraction scanning calorimetry (DSC), nitrogen physisorption analysis and transmission electron microscope (TEM). MTT assay, AO and Annexin V-FITC/PI staining were performed to explore the anti-tumour activity of Tf-Res-MSN. The results showed that Tf-Res-MSN significantly decreased cell viability and increased cell apoptosis. The inhibition rate and apoptotic rate of Tf-Res-MSN in MCF-7 cells were 95.75% and 80.8%, respectively. CONCLUSION: Our study demonstrated that Tf-Res-MSN was a valuable technique with potential value in breast cancer applications.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Sistemas de Liberação de Medicamentos/métodos , Células MCF-7 , Resveratrol/farmacologia , Catepsina B/farmacologia , Dióxido de Silício , Transferrina/farmacologia , Transferrina/uso terapêutico , Portadores de Fármacos/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Peptídeos/farmacologia , Nanopartículas/química , Apoptose , Porosidade
6.
Anal Biochem ; 659: 114958, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36273622

RESUMO

The percentage of glycated hemoglobin (HbA1c) in total hemoglobin (Hb) is an important index for the diagnosis of Type II diabetes (T2D) because it reflects the long-term glucose level in blood. Herein, employing a one-pot co-reduction approach using glutathione (GSH) as structure-directing agent, a cluster-like AuAg nanoparticle (AuAg NPs) material was synthesized, therefore an electrochemiluminescence (ECL) aptamer-sensor for HbA1c detection was developed based on functionalized electrode with this material. Meanwhile, the quantitative determination of total Hb was realized based on the quenching effect of Hb on the fluorescence (FL) of luminol. Under compatible conditions, the results of both indexes can be satisfactorily acquired. This multimodal detection system has a good linear response toward Hb from 0.1 to 2.5 µM and HbA1c from 0.005 to 0.5 µM. The blood test proves this strategy is capable of accurate Hb and HbA1c detection, thus to obtain the percentage of HbA1c in total Hb (HbA1c%), which has the potential application for clinical diagnosis of diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Hemoglobinas Glicadas/análise , Diabetes Mellitus Tipo 2/diagnóstico , Luminol , Eletrodos , Testes Hematológicos
7.
Front Psychol ; 13: 980049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248493

RESUMO

Colour is an important guideline for selection and consumption. It also draws attention to the designers, as some modern design styles require them to illustrate the taste of the product with a limited number of colours. In this case, a precise description of the taste-colour association is required. The present study explored the colour-taste crossmodal association of two tastes, crisp and dry, which are normally found in beers and are the preferred flavours of Chinese consumers. Experiments were carried out to determine the characteristics of the colours associated with the two tastes. And the strength of the tastes perceived from the colours with different hue angles was investigated. The results of this study reveal that the hue and chroma can both affect the perception of these tastes. Both tastes can be perceived from the same colour, but the strength of the taste can be varied from different hues.

8.
Toxicology ; 468: 153113, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35101590

RESUMO

5-Fluorouracil (5-FU) was a key chemotherapeutic agent in the treatment of different solid tumors. However, cardiotoxicity was included among the therapeutic strategies of 5-FU. The molecular mechanism of cardiotoxicity induced by 5-FU remains unclear. The aim of the study was to investigate whether ferroptosis was involved in 5-FU-induced cardiotoxicity in vivo and in vitro. The in vivo cardiotoxicity model was induced by intraperitoneal injection of 5-FU at the dose of 15, 30, 60 mg/kg for 7 days. Body weight, general condition and plasma enzyme activities of the mice were observed to evaluate heart function. In addition, HE staining, MASSON staining and TEM technology was used. Western-blot analysis were performed to evaluate the protein level of iron transport, iron storage and reactive oxygen species (ROS) of ferroptosis. In H9c2 cardiomyocyte cells, cell viability, generation of ROS, mitochondrial activity and cellular Fe2+ levels were measured. The in vivo results showed that 5-FU significantly impaired cardiac function and structure. The serum creatine kinase (CK) and lactate dehydrogenase (LDH) levels were significantly increased in 5-FU group. HE and MASSON staining showed that 5-FU caused structural injuries. In addition, 5-FU increased the level of ferroptosis markers involving malonaldehyde (MDA) and Fe2+ content. Ferrostatin-1 (Fer-1) was an aromatic amine that specifically binds with lipid ROS and protects cells against lipid peroxidation. Furthermore, 5-FU markedly induced ferroptosis in H9c2 cardiomyocyte cells, which mainly embodied as declined cell vitality, accumulated iron, elevated lipid peroxides. Conversely, inhibition of ferroptosis by Fer-1 completely abolished 5-FU-induced effects. Both in vivo and in vitro experiments indicated that 5-FU increased the expression of ferroptosis, mainly by reducing the expression of glutathione peroxidase 4 (GPX4) and ferritin heavy chain 1 (FTH1), but enhancing the expression of transferrin receptor 1 (TfR1). In conclusion, the present study suggested that ROS and iron homeostasis dependent ferroptosis played a vital role in 5-FU induced cardiotoxicity.


Assuntos
Ferroptose/fisiologia , Ferro/metabolismo , Miocárdio/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Western Blotting , Peso Corporal/efeitos dos fármacos , Corantes , Creatina Quinase/sangue , Ecocardiografia , Amarelo de Eosina-(YS) , Corantes Fluorescentes , Fluoruracila/farmacologia , Coração/anatomia & histologia , Coração/efeitos dos fármacos , Coração/fisiologia , Hematoxilina , Homeostase , L-Lactato Desidrogenase/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Mitocôndrias/fisiologia , Miocárdio/ultraestrutura , Tamanho do Órgão/efeitos dos fármacos , Plasma/química , Nitrato de Prata
9.
Toxicol Appl Pharmacol ; 435: 115852, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973290

RESUMO

Imatinib Mesylate (IMA) has been widely used to treat with chronic myeloid leukemia (CML). However, cardiotoxicity associated with IMA is included among the therapeutic strategies. The present study was aimed to discover whether ferroptosis, a programmed iron-dependent cell death, is involved in IMA-induced cardiotoxicity. In vivo, mouse model was established after treated with 25 mg/kg, 50 mg/kg and 100 mg/kg IMA. Serum CK, LDH, AST activities were determined. Cardiac tissues were examined by H&E and Oil Red O staining. MDA was measured to assess production of lipid peroxide. Tissue iron and GSH content were measured. In vitro, cell viability, mitochondria membrane potential, generation of reactive oxygen species (ROS) and cellular iron levels were performed to explore the mechanism of IMA. The in vivo results revealed that IMA treatment significantly increased serum CK, LDH and AST. H&E staining showed that IMA caused cardiac structural injuries. The dose-dependent decrease of GSH and increase of tissue iron and MDA were observed in IMA-treated groups. Oil Red O staining suggested obvious cardiac lipid accumulation after treated with IMA. In H9c2 cardiomyocytes, IMA significantly inhibited cell proliferation in a dose-dependent manner. Mitochondria membrane potential assay showed that IMA destroyed the mitochondrial function. Additionally, IMA increased the cellular ROS and iron levels. Furthermore, IMA down-regulated the expression of Nrf2 and up-regulated the expression of P53 and TfR. These results provided compelling evidence that ferroptosis participates in IMA-induced cardiotoxicity. Ferroptosis could be regarded as a target to protect against cardiotoxicity in IMA-exposed patients.


Assuntos
Antineoplásicos/toxicidade , Cardiotoxicidade , Ferroptose/efeitos dos fármacos , Mesilato de Imatinib/toxicidade , Fator 2 Relacionado a NF-E2/biossíntese , Inibidores de Proteínas Quinases/toxicidade , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Glutationa/metabolismo , Ferro/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Espécies Reativas de Oxigênio/metabolismo
10.
Psychol Med ; 52(7): 1386-1392, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32829730

RESUMO

BACKGROUND: No studies have reported on how to relieve distress or relax in medical health workers while wearing medical protective equipment in coronavirus disease 2019 (COVID-19) pandemic. The study aimed to establish which relaxation technique, among six, is the most feasible in first-line medical health workers wearing medical protective equipment. METHODS: This was a two-step study collecting data with online surveys. Step 1: 15 first-line medical health workers were trained to use six different relaxation techniques and reported the two most feasible techniques while wearing medical protective equipment. Step 2: the most two feasible relaxation techniques revealed by step 1 were quantitatively tested in a sample of 65 medical health workers in terms of efficacy, no space limitation, no time limitation, no body position requirement, no environment limitation to be done, easiness to learn, simplicity, convenience, practicality, and acceptance. RESULTS: Kegel exercise and autogenic relaxation were the most feasible techniques according to step 1. In step 2, Kegel exercise outperformed autogenic relaxation on all the 10 dimensions among the 65 participants while wearing medical protective equipment (efficacy: 24 v. 15, no space limitation: 30 v. 4, no time limitation: 31 v. 4, no body position requirement: 26 v. 4, no environment limitation: 30 v. 11, easiness to learn: 28 v. 5, simplicity: 29 v. 7, convenience: 29 v. 4, practicality: 30 v. 14, acceptance: 32 v. 6). CONCLUSION: Kegel exercise seems a promising self-relaxation technique for first-line medical health workers while wearing medical protective equipment among COVID-19 pandemic.


Assuntos
COVID-19 , COVID-19/prevenção & controle , Pessoal de Saúde , Humanos , Pandemias/prevenção & controle , Equipamentos de Proteção , Terapia de Relaxamento
11.
Cancer Invest ; 39(8): 675-684, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34241563

RESUMO

The major problems with cancer therapy are drug-induced side effects. There is an urgent need for safe anti-tumor drugs. Artemisinin is a Chinese herbal remedy for malaria with efficacy and safety. However, several studies reported that artemisinin causes neurotoxicity and cardiotoxicity in animal models. Recently, nanostructured drug delivery systems have been designed to improve therapeutic efficacy and reduce toxicity. Artemisinin has been reported to show anticancer properties. The anticancer effects of artemisinin appear to be mediated by inducing cell cycle arrest, promoting ferroptosis and autophagy, inhibiting cell metastasis. Therefore, the review is to concentrate on mechanisms and molecular targets of artemisinin as anti-tumor agents. We believe these will be important topics in realizing the potential of artemisinin and its derivatives as potent anticancer agents.


Assuntos
Antineoplásicos/uso terapêutico , Artemisininas/uso terapêutico , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia , Artemisininas/farmacologia , Humanos
12.
Psychother Psychosom ; 90(2): 127-136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33152729

RESUMO

BACKGROUND: As the fight against the COVID-19 epidemic continues, medical workers may have allostatic load. OBJECTIVE: During the reopening of society, medical and nonmedical workers were compared in terms of allostatic load. METHODS: An online study was performed; 3,590 Chinese subjects were analyzed. Socio-demographic variables, allostatic load, stress, abnormal illness behavior, global well-being, mental status, and social support were assessed. RESULTS: There was no difference in allostatic load in medical workers compared to nonmedical workers (15.8 vs. 17.8%; p = 0.22). Multivariate conditional logistic regression revealed that anxiety (OR = 1.24; 95% CI 1.18-1.31; p < 0.01), depression (OR = 1.23; 95% CI 1.17-1.29; p < 0.01), somatization (OR = 1.20; 95% CI 1.14-1.25; p < 0.01), hostility (OR = 1.24; 95% CI 1.18-1.30; p < 0.01), and abnormal illness behavior (OR = 1.49; 95% CI 1.34-1.66; p < 0.01) were positively associated with allostatic load, while objective support (OR = 0.84; 95% CI 0.78-0.89; p < 0.01), subjective support (OR = 0.84; 95% CI 0.80-0.88; p < 0.01), utilization of support (OR = 0.80; 95% CI 0.72-0.88; p < 0.01), social support (OR = 0.90; 95% CI 0.87-0.93; p < 0.01), and global well-being (OR = 0.30; 95% CI 0.22-0.41; p < 0.01) were negatively associated. CONCLUSIONS: In the post-COVID-19 epidemic time, medical and nonmedical workers had similar allostatic load. Psychological distress and abnormal illness behavior were risk factors for it, while social support could relieve it.


Assuntos
Alostase/fisiologia , Ansiedade/fisiopatologia , COVID-19 , Depressão/fisiopatologia , Pessoal de Saúde , Comportamento de Doença/fisiologia , Satisfação Pessoal , Apoio Social , Estresse Psicológico/fisiopatologia , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações
13.
Biol Pharm Bull ; 43(5): 864-872, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378562

RESUMO

Cardiac fibrosis is a major contributor for diabetic cardiomyopathy and Dendrobium officinale possessed therapeutic effects on hyperglycemia and diabetic cardiomyopathy. To further investigate the possible mechanisms of the Dendrobium officinale on diabetic myocardial fibrosis in mice. Water-soluble extracts of Dendrobium officinale (DOE) from dry stem was analyzed by HPLC and phenol-sulfuric acid method. Diabetic mice were induced by intraperitoneal injection of streptozotocin (STZ) (30 mg/kg) for 4 consecutive days after intragastric administration of a high-fat diet (HFD) for 2 weeks. The groups were as follows: control group, model group, DOE low, medium, high dose group (75, 150, 300 mg/kg) and Metformin positive group (125 mg/kg). The results showed that DOE dose-dependently lower serum insulin, total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and grew the high-density lipoprotein cholesterol (HDL-C) after 12 weeks of daily administration with DOE. Hematoxylin-eosin staining and Sirius red staining showed obvious amelioration of cardiac injury and fibrosis. In addition, the result of immunoblot indicated that DOE increased the expression of peroxisome proliferator activated receptor-α (PPAR-α), phosphorylation of insulin receptor substrate 1 (p-IRS1) and E-cadherin and repressed the expression of transforming growth factor ß1 (TGF-ß1), phosphorylation of c-Jun N-terminal kinase (p-JNK), Twist, Snail1 and Vimentin. The present findings suggested that DOE ameliorated HFD/STZ-induced diabetic cardiomyopathy (DCM). The possible mechanism mainly associated with DOE accelerating lipid transport, inhibiting insulin resistant and suppressing fibrosis induced by epithelial mesenchymal transition (EMT).


Assuntos
Dendrobium , Diabetes Mellitus Experimental/tratamento farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Miocárdio/patologia , Extratos Vegetais/uso terapêutico , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Dieta Hiperlipídica , Fibrose , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Caules de Planta , Transdução de Sinais/efeitos dos fármacos
14.
Nanomaterials (Basel) ; 10(2)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054026

RESUMO

A thermal plasma process at atmospheric pressure is an attractive method for continuous synthesis of graphene flakes. In this paper, a magnetically rotating arc plasma system is employed to investigate the effects of buffer gases on graphene flakes synthesis in a thermal plasma process. Carbon nanomaterials are prepared in Ar, He, Ar-H2, and Ar-N2 via propane decomposition, and the product characterization is performed by transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and the Brunauer-Emmett-Teller (BET) method. Results show that spherical particles, semi-graphitic particles, and graphene flakes coexist in products under an Ar atmosphere. Under an He atmosphere, all products are graphene flakes. Graphene flakes with fewer layers, higher crystallinity, and a larger BET surface area are prepared in Ar-H2 and Ar-N2. Preliminary analysis reveals that a high-energy environment and abundant H atoms can suppress the formation of curved or closed structures, which leads to the production of graphene flakes with high crystallinity. Furthermore, nitrogen-doped graphene flakes with 1-4 layers are successfully synthesized with the addition of N2, which indicates the thermal plasma process also has great potential for the synthesis of nitrogen-doped graphene flakes due to its continuous manner, cheap raw materials, and adjustable nitrogen-doped content.

15.
Biomicrofluidics ; 13(4): 044115, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31531152

RESUMO

Herein, a novel cell-based electrochemiluminescent (ECL) sensing matrix was developed for probing reactive oxygen species (ROSs) produced from mouse macrophage cells. Uniformly sized Au nanoparticles (AuNPs) with an average diameter of 16 nm were decorated on the surface of indium tin oxide (ITO) glass through the connection of hydrolyzed 3-aminopropyl trimethoxysilane (APTMS) serving as a sensor substrate. Then, the surface was covered with a poly-l-lysine thin film, where mouse macrophage cells were successfully cultured. The morphology of the electrodes obtained was characterized by scanning electron microscopy and atomic force microscopy, and their electrochemical properties were investigated by electrochemical impedance spectroscopy. A linear response was observed from the AuNPs/APTMS/ITO substrate with a sensitivity of 0.465 units per mg/l of H2O2, and a higher sensitivity of 207 units per mg/l of zymosan. Thereafter, a factor of 84 molecules of H2O2 produced by a single glycogen was estimated. The results demonstrated that the ECL response of this cell-based sensor quantitatively correlated with yielded ROSs during cell oxygen metabolism under the stimulation of zymosan. This work suggests that the prepared sensing matrix is efficient for monitoring the oxygen metabolism of living cells and can be applied in biological and clinical fields to provide significant information on the regular or abnormal function of cells.

16.
J Colloid Interface Sci ; 516: 476-483, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29408137

RESUMO

Herein, prickly platinum-palladium core-shell nanocrystals (Pt@Pd NCs) were prepared by a facile one-pot aqueous method, only taking sodium pyrrolidone carboxylate (PCA-Na) as the structure director and stabilizing agent. The products were mainly characterized by microscopic analysis, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), followed by discussing the formation mechanism in details. The electrochemical characterizations were examined by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and chronoamperometry (CA). The results revealed that the prepared architectures had the biggest current density (58.4 mA cm-2) for ethylene glycol oxidation, which is 3.5-fold, 1.2-fold, 2.3-fold and 2.4-flod enhancement relative to those of home-made single Pt nanoparticles (NPs) and Pd NPs, commercial Pt black and Pd black catalysts, respectively. Also, the obtained Pt@Pd NCs showed improved catalytic activity and stability towards glycerol oxidation and hydrogen evolution reactions compared to the references.

17.
J Colloid Interface Sci ; 514: 93-101, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29245076

RESUMO

Herein, we developed a facile one-pot co-reduction method to fabricate highly dentritic platinum-palladium/palladium core-shell nanocrystals on reduced graphene oxide (PtPd@Pd NCs/rGO), where poly-l-lysine (PLL) worked as the eco-friendly structure director and stabilizer. The nanocomposite was mainly characterized by microscopic analysis, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), along with the discussion of the formation mechanism. The synthesized PtPd@Pd NCs/rGO have the enlarged electrochemically active surface area (ECSA) of 51.65 m2 g-1, showing 1.3 folds enhancement in the peak current density relative to commercial Pt/C (50 wt%) for glycerol oxidation reaction (GOR), coupled with the small Tafel slope of 28 mV dec-1 for hydrogen evolution reaction (HER).

18.
PLoS One ; 12(12): e0189462, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29236772

RESUMO

While aging is associated with increased knowledge, it is also associated with decreased semantic integration. To investigate brain activation changes during semantic integration, a sample of forty-eight 25-75 year-old adults read sentences with high cloze (HC) and low cloze (LC) probability while functional magnetic resonance imaging was conducted. Significant age-related reduction of cloze effect (LC vs. HC) was found in several regions, especially the left middle frontal gyrus (MFG) and right inferior frontal gyrus (IFG), which play an important role in semantic integration. Moreover, when accounting for global gray matter volume reduction, the age-cloze correlation in the left MFG and right IFG was absent. The results suggest that brain structural atrophy may disrupt brain response in aging brains, which then show less brain engagement in semantic integration.


Assuntos
Envelhecimento/fisiologia , Substância Cinzenta/diagnóstico por imagem , Semântica , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Probabilidade
19.
J Colloid Interface Sci ; 508: 551-558, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28866463

RESUMO

In this work, AuPd@Pd core-shell nanocrystals (AuPd@Pd NCs) were fabricated by a one-pot co-reduction approach, where theophylline-7-acetic acid (TAA) acted asa new structure-directing agent. The crystal structure and composition were mainly characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray diffraction (XRD), together with X-ray photoelectron spectroscopy (XPS). The growth mechanism of AuPd@Pd NCs was investigated in detail. The obtained AuPd@Pd NCs exhibited superior catalytic characters for formic acid oxidation reaction (FAOR) and glycerol oxidation reaction (GOR) in contrast with commercial Pd black in alkaline media.

20.
J Interferon Cytokine Res ; 36(9): 552-62, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27348082

RESUMO

Interleukin (IL)-33 is a novel member of the IL-1 superfamily of cytokines that has recently become a focal point for research into the pathogenesis of atopic dermatitis (AD). However, the expression and regulation of IL-33 in human epidermal keratinocytes have not well been delineated. The aim of this study was to evaluate IL-33 and its receptor ST2L expression in skin lesions of AD patients and explored the signal transduction mechanisms leading to the IL-33 expression and of the IL-33's pharmacological action in keratinocytes from AD patients (ADKs) and those from healthy controls (NHEKs). We performed immunocytochemistry, reverse transcription-polymerase chain reaction, Western blotting, and enzyme-linked immunosorbent assay to investigate ADKs compared with NHEKs. We found that IL-33/ST2L were positively expressed in the skin lesions of AD patients and a high expression of IL-33 was induced in keratinocytes by IL-4 plus interferon [IFN]-γ or IFN-γ alone at the mRNA and protein levels. Meanwhile, IFN-γ induced IL-33 expression through extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), epidermal growth factor receptor (EGFR), and Janus kinase/signal transducer and activator of transcription. The expression of ST2L was increased in a time- and dose-dependent manner in both types of cells incubated with IL-33, and was especially increased in ADKs compared with NHEKs. We examined the cytokine IL-6 and the chemokines CXCL-8/IL-8, CCL-20, CCL-17, CCL-5, and CCL-2 in keratinocytes, which showed increased expression in a time- and dose-dependent manner in ADKs when induced by IL-33. Furthermore, 4 signaling pathways (ERK, p38 MAPK, c-Jun N-terminal kinase, and nuclear factor-κB) were involved in the IL-33-mediated induction in both cells. In conclusion, IL-33 is closely interlinked in AD skins and keratinocytes. IL-33 plays an important role in the pathogenesis of immune inflammatory responses in AD, which might be a possible therapeutic target in the treatment of AD.


Assuntos
Epiderme/metabolismo , Regulação da Expressão Gênica , Interleucina-33/genética , Interleucina-33/metabolismo , Queratinócitos/metabolismo , Quimiocinas/metabolismo , Citocinas/genética , Citocinas/metabolismo , Dermatite Atópica/genética , Dermatite Atópica/metabolismo , Dermatite Atópica/patologia , Humanos , Mediadores da Inflamação/metabolismo , Interferon gama/metabolismo , Interferon gama/farmacologia , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos
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