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1.
Small ; : e2401258, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38794878

RESUMO

Manganese oxide-based aqueous zinc-ion batteries (ZIBs) are attractive energy storage devices, owing to their good safety, low cost, and ecofriendly features. However, various critical issues, including poor conductivity, sluggish reaction kinetics, and unstable structure still restrict their further development. Oxygen defect engineering is an effective strategy to improve the electrochemical performance of manganese oxides, but challenging in the accurate regulation of oxygen defects. In this work, an effective and controllable defect engineering strategy-controllable electrochemical lithium-ion intercalation - is proposed to tackle this issue. The incorporation of lithium ions and oxygen defects can promote the conductivity, lattice spacing, and structural stability of Mn2O3 (MO), thus improving its capacity (232.7 mAh g-1), rate performance, and long-term cycling stability (99.0% capacity retention after 3000 cycles). Interestingly, the optimal ratio of intercalated lithium-ion varies at different temperature or mass-loading of MO, which provides the possibility to customize diverse ZIBs to meet different application conditions. In addition, the fabricated ZIBs present good flexibility, superior safety, and admirable adaptability under extreme temperatures (-20-100 °C). This work provides an inspiration on the structural customization of metal oxide nanomaterials for diverse ZIBs, and sheds light on the construction of future portable electronics.

2.
Environ Sci Technol ; 58(13): 5760-5771, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38507818

RESUMO

Robust empirical assessments of the long-term cumulative global effects of free trade and economic globalization on the environment are limited. This account fills this gap by constructing a dynamic computable general equilibrium model to estimate the environmental effects of a milestone in the recent history of trade liberalization: China's 20-year World Trade Organization (WTO) accession. The modeling shows that China's accession could have resulted in an increase in the global cumulative greenhouse gases (GHGs), sulfur dioxide (SO2), and nitrogen oxide (NOx) emissions by roughly 14,000 Mt CO2-eq, 64 Mt, and 46 Mt, respectively. The global production scale effect contributed to most of these estimated increases. The regional total output composition effect also caused higher emissions. Meanwhile, the sectoral output composition effect helped reduce total emissions to a limited extent. Fortunately, a package of emission abatement measures led to a decrease in emission factors and a drop in the global cumulative emissions of GHGs, SO2, and NOx. The findings suggest that to enjoy the free trade and economic globalization benefits and minimize the induced emission increases, it is vitally important to systemically reduce emissions across the entire economy and nurture a low-carbon trade regime.


Assuntos
Meio Ambiente , Gases de Efeito Estufa , Dióxido de Enxofre , Internacionalidade , China , Dióxido de Carbono/análise
3.
Muscle Nerve ; 67(6): 481-488, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36945795

RESUMO

INTRODUCTION/AIMS: Descriptions of the clinical characteristics of anti-AChR-MuSK-LRP4 antibody-negative myasthenia gravis (triple-negative myasthenia gravis, TNMG) are lacking in the current literature. Therefore, we investigated the clinical characteristics of TNMG in Chinese patients. METHODS: We retrospectively analyzed 925 patients with MG registered in the Department of Neuroimmunology, Henan Institute of Medical and Pharmaceutical Sciences from January 2015 to March 2021. RESULTS: One hundred six patients diagnosed with TNMG were included in the study. The average age of onset was 32.4 y, with a male-to-female ratio of 1:1. The age of onset showed a bimodal distribution: 0-9 y and 40-49 y. Adult patients were more likely to have weakness of limb and bulbar muscles (p < .05). Thymic hyperplasia was found in 20.2% of the patients. Younger patients were more likely to relapse. The rate of adult early-onset myasthenia gravis reaching complete stable remission and pharmacological remission was 47.6%, and the prognosis was better than that in juvenile-onset myasthenia gravis (p = .019). Older age of onset was the only risk factor for the development of generalized TNMG from ocular TNMG (R = 1.046, p = .002, 95% confidence interval 1.017-1.077). DISCUSSION: This study showed that the clinical characteristics of patients with TNMG varied among the different age groups. Significant findings included a bimodal distribution of onset age, coexisting thymic hyperplasia, and a generally favorable prognosis.


Assuntos
Miastenia Gravis , Hiperplasia do Timo , Adulto , Humanos , Masculino , Feminino , Receptores Colinérgicos , Estudos Retrospectivos , Receptores Proteína Tirosina Quinases , Autoanticorpos , Recidiva Local de Neoplasia , Miastenia Gravis/diagnóstico , Miastenia Gravis/epidemiologia , China/epidemiologia , Proteínas Relacionadas a Receptor de LDL
4.
J Environ Manage ; 345: 118870, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37678024

RESUMO

Based on data from 335 cities in China, this study employs the standard deviation ellipse method to portray unbalanced and differential spatiotemporal evolution patterns of environmental emissions and socioeconomic elements. A logarithmic mean Divisia index analysis and in-depth discussion are carried out to disclose the main driving factors and underlying reasons for the differences. Decoupling trends exist among carbon emissions, gross domestic product (GDP) and population in terms of their gravity center migrations. The standard deviation ellipse direction of carbon emissions gradually changed from 'northeast‒southwest' to 'northwest‒southeast', and the standard deviation ellipse areas of carbon emissions and air pollution continuously expanded over time; at the same time, that of GDP contracted. Economic growth has always been the main driver of carbon emissions and air pollution nationally, but its role has weakened. Moreover, decreases in the energy intensity and carbon and pollution intensities are the main factors contributing to emissions reductions. Differentiated spatiotemporal economic structure evolution, regional heterogeneities in the energy intensity and efficiency, and cross-region power energy transmissions are identified as the underlying reasons for the unbalanced spatiotemporal patterns of the environmental emissions and socioeconomic elements. Based on these findings, policy suggestions can be made to address the imbalances and promote carbon mitigation, air quality improvement and high-quality social-economic development at the city level.


Assuntos
Poluição do Ar , Carbono , Cidades , Poluição Ambiental
5.
Environ Sci Policy ; 145: 50-59, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37070073

RESUMO

The emergency response to the COVID-19 pandemic had an extreme exogenous impact on society and the economy. This paper aims to explore the impacts of the national emergency response and the subsequent emergency response termination on air quality and its policy implications through regression discontinuity design (RDD) estimation by employing panel data on daily air quality from January 1, 2019, to July 31, 2020, for 290 cities in China. The empirical results showed that the emergency response resulted in a significant decrease in most of the major pollutant concentrations within a short time frame, and the average air quality index (AQI) decreased by approximately 11.0%. The concentrations of PM2.5, PM10, SO2, NO2, and CO decreased by approximately 18.8%, 13.1%, 13.5%, 11.1% and 6.7%, respectively, while the O3 concentration did not change significantly. Further causal analysis found that mandatory traffic restrictions and the shutdown of industries were two important factors that contributed greatly to air quality improvement. Moreover, since the process of returning to normal daily activities and promoting the economy were gradual, the results showed that air pollution did not rebound immediately after the government called for the "resumption of production and work" and announced the "termination of the emergency response". Our findings suggest that to achieve a substantial and sustainable improvement in air quality, it is necessary to continuously implement strict emission control routines and take co-control measures for various VOCs precursors of ozone.

6.
Entropy (Basel) ; 25(6)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37372282

RESUMO

Accurate traffic flow forecasting is very important for urban planning and traffic management. However, this is a huge challenge due to the complex spatial-temporal relationships. Although the existing methods have researched spatial-temporal relationships, they neglect the long periodic aspects of traffic flow data, and thus cannot attain a satisfactory result. In this paper, we propose a novel model Attention-Based Spatial-Temporal Convolution Gated Recurrent Unit (ASTCG) to solve the traffic flow forecasting problem. ASTCG has two core components: the multi-input module and the STA-ConvGru module. Based on the cyclical nature of traffic flow data, the data input to the multi-input module are divided into three parts, near-neighbor data, daily-periodic data, and weekly-periodic data, thus enabling the model to better capture the time dependence. The STA-ConvGru module, formed by CNN, GRU, and attention mechanism, can capture both temporal and spatial dependencies of traffic flow. We evaluate our proposed model using real-world datasets and experiments show that the ASTCG model outperforms the state-of-the-art model.

7.
Environ Sci Technol ; 56(17): 12656-12666, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35943862

RESUMO

Global dairy production, consumption, and trade are growing rapidly, driven by population and per capita income growth and increasing health concerns mainly from developing countries, which has aroused concerns about the related carbon emission (mostly in the form of methane) increase. If all of the dairy products consumed were produced locally/domestically in the developing countries/economies (a counterfactual scenario), the carbon emissions in 2018 would be 28 Mt CO2-equiv higher than its status quo (a factual scenario). The present study indicates that unlike in many global trade cases in which carbon leakages are from developed to developing countries, global dairy trade is characterized by net embodied carbon flows from developed to developing countries/economies due to the fact that there is an overwhelming one-way-flow of dairy products from developed to developing countries/economies. The differences in the carbon emission factors between the developed and developing countries/economies provide an opportunity that global dairy trade and production specialization can help to reduce carbon emissions from increasing dairy product demand, and the total reduction potential is estimated to be about 414 Mt CO2-equiv from 2018 to 2030. Free trade agreements such as the Regional Comprehensive Economic Partnership will incentivize larger carbon emission reduction benefits through promoting dairy trade.


Assuntos
Dióxido de Carbono , Carbono , Comércio , Desenvolvimento Econômico , Renda
8.
Clin Immunol ; 224: 108676, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33465495

RESUMO

In this study, the potential of specific Circular RNAs (circRNAs) as novel peripheral blood biomarkers for myasthenia gravis (MG) was explored. We analyzed circRNAs in the peripheral blood of three normal controls and three MG patients using RNA microarray. Candidate circRNAs were validated in three independent cohorts by Quantitative Real-time polymerase chain reaction (qPCR). Eleven differentially expressed circRNAs were initially identified and four were confirmed in the first independent cohort. Hsa_circ_0076490 and hsa-circ_5333-4 had the largest areas under the curve (AUCs) of the receiver operating characteristics (ROC) and were validated in the second cohort. In the third cohort, hsa-circRNA5333-4 had a larger AUC: 0.864 (95% confidence interval [CI] = 0.801-0.928, P < 0.001), a stronger correlation with the Quantitative Myasthenia Gravis Score (qMG): r = 0.505 (P < 0.001) and was correlated with gender and acetylcholine receptor antibody levels (P < 0.05). So hsa-circRNA5333-4 represents a novel biomarker for the diagnosis and monitoring of MG.


Assuntos
RNA Circular/sangue , RNA Circular/química , Albumina Sérica Humana/química , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/sangue , Miastenia Gravis/genética , Curva ROC , Reprodutibilidade dos Testes , Adulto Jovem
9.
Analyst ; 145(10): 3749-3756, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32319461

RESUMO

Reduced graphene oxide (rGO) and Au nanodot (AuND, ∼1.5 nm) modified rGO, referred to as AuNDs-rGO, synthesized by a simple photochemical reduction method, are used for electrochemical biosensors. Our experimental results showed that the glucose oxidase (GOX)/rGO/Nafion/glassy carbon electrode (GCE) exhibits a linear range from 0.03 to 6.28 mM and a detection limit of 0.03 mM at a signal-to-noise (S/N) ratio of 3 for the amperometric sensing of glucose, while the GOX/AuNDs-rGO/Nafion/GCE shows a wider linear range from 0.02 to 8.82 mM and a lower detection limit of 0.02 mM. This difference may arise from the high catalytic activity of the AuNDs. Our studies demonstrate that the composites of rGO/Nafion and AuNDs-rGO/Nafion might offer a new class of electrode materials, and provide a promising platform for biosensing applications.


Assuntos
Técnicas Biossensoriais/métodos , Ouro/química , Grafite/química , Nanopartículas/química , Eletroquímica , Glucose/análise , Limite de Detecção , Modelos Lineares , Oxirredução , Fatores de Tempo
10.
Chem Pharm Bull (Tokyo) ; 68(5): 421-427, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378540

RESUMO

The aim of this study was to evaluate the effects of Magnolin (MGL) on inhibition of human breast cancer cells, and explore the underlying molecular mechanisms. The viability of the treated cells was assessed with the Cell Counting Kit-8 (CCK-8) assay, and the proliferation was analyzed in terms of EdU uptake, colony formation, and flow cytometry. The in vitro invasion and migration were determined by the transwell and wound healing assays respectively. The mRNA and protein levels of relevant factors was evaluated by quantitative real-time PCR and Western blotting respectively. MGL significantly decreased the viability and promoted apoptosis of MDA-MB-231 cells, along with reducing EdU incorporation rate as well as the colony forming capacity compared to the untreated control cells. In addition, the in vitro invasion and migration were also significantly inhibited by MGL. Furthermore, MGL suppressed the phosphorylation of MEK1/2, extracellular signal-regulated kinase (ERK)1/2 and significantly downregulated the expression of cyclin-dependent kinase 1 (CDK1), the anti-apoptotic B-cell lymphoma 2 (BCL2) and metastasis-associated matrix metalloproteases (MMPs) 2 & 9, and upregulated the cleaved caspases 3 and 9. After ERK was completely inhibited with the small interfering RNA (siRNA), MGL had no effect on these factors, indicating that ERK is essential for MGL action in breast cancer. In conclusion, MGL inhibits proliferation and invasion of and induces apoptosis in breast cancer cells through the ERK pathway.


Assuntos
Antineoplásicos/farmacologia , Lignanas/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lignanas/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Relação Estrutura-Atividade , Cicatrização/efeitos dos fármacos
12.
Muscle Nerve ; 55(1): 84-90, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26616645

RESUMO

INTRODUCTION: Chemokine CC motif receptors 9 and 7 (CCR9 and CCR7) play a major role in the migration of T-cell precursors to the thymus to initiate T thymopoiesis. However, their role in development of T-cells in myasthenia gravis (MG) patients has not been fully elucidated. METHODS: Expression and distribution of CCR9+ and CCR7+ cells were detected by flow cytometry and immunofluorescence. Real-time polymerase chain reaction was used to check the adhesion molecules on CD4- CD8- double-negative (DN) thymocytes. RESULTS: CCR9 and CCR7 expression by DN thymocytes increased in the MG thymus; the levels of CCR9, CCR7, interleukin-7R mRNA increased, and CXCR4 levels decreased compared with levels in the non-MG thymus. More CCR7 and CCR9 double-positive (DP) thymocytes were gathered near the subcapsular region in MG thymus. CONCLUSIONS: Enhanced expression of CCR9 and CCR7 may complicate the differentiation of DP thymocytes from the DN stage in MG thymus. Muscle Nerve, 2016 Muscle Nerve 55: 84-90, 2017.


Assuntos
Miastenia Gravis/patologia , Receptores CCR7/metabolismo , Receptores CCR/metabolismo , Timócitos/metabolismo , Adolescente , Adulto , Antígenos CD4/metabolismo , Antígenos CD8/metabolismo , Criança , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica , Humanos , Masculino , Fragmentos de Peptídeos/metabolismo , RNA Mensageiro/metabolismo , Receptores CCR/genética , Receptores CCR7/genética , Timo/patologia , Adulto Jovem
13.
Int J Med Sci ; 14(7): 698-704, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28824303

RESUMO

Background: Increased cardiomyocyte apoptosis under high glucose condition contributes to diabetic cardiomyopathy. Degradation of cardiac Connexin43 (Cx43) has been associated with cardiac dysfunction in diabetic heart. Clinical and experimental studies suggested that metformin (Met) exhibits cardioprotective properties against diabetes. Aim: The aim of this study was to investigate the effect and underlying signaling mechanisms of metformin on apoptosis and Cx43 expression in H9c2 cells presenting with hyperglycemia conditions. Methods: In the present study, H9c2 cardiac cells were incubated with 5.5 mM glucose, 33.3 mM glucose, 33.3 mM glucose with metformin at two dose (100 µM, 1 mM) for 96 hours, and 1 mM metformin with chloroquine (50 µM) in 33.3 mM glucose medium. Cell viability was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) cell survival assay. Cytotoxicity was determined by the release of lactate dehydrogenase (LDH). The expression of Cx43, autophagic maker protein (LAMP-1, Beclin-1, p62 and LC3) and apoptosis maker protein (Bcl-2 and Bax) were determined by western blot. Results: The results showed that high glucose increased apoptosis and decreased Cx43 expression. Interestingly, metformin attenuated hyperglycemia-increased apoptosis and restored Cx43 expression. Moreover, this treatment caused autophagy as well, which indicated by up-regulation of autophagy-related proteins LAMP-1, Beclin-1, p62 and reduction in the ratio of LC3-II/LC3-I. In addition, administration autophagy inhibitor chloroquine (CQ) did not block the effect of metformin on Cx43 expression while increasing Cx43 content, together with an increased apoptosis. Conclusion: Administration metformin can protect the H9c2 cells against hyperglycemia-induced apoptosis and Cx43 down-regulation, in part, mediated through the induction of autophagy pathway.


Assuntos
Autofagia/efeitos dos fármacos , Conexina 43/genética , Diabetes Mellitus/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Metformina/administração & dosagem , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Autofagia/genética , Linhagem Celular , Cloroquina/administração & dosagem , Diabetes Mellitus/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hiperglicemia/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Transdução de Sinais/efeitos dos fármacos
14.
Muscle Nerve ; 53(5): 711-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26403759

RESUMO

INTRODUCTION: Myasthenia gravis (MG) occurs globally, and many studies have indicated that there are regional differences in epidemiology, biomarkers, and prognosis of MG. METHODS: A total of 478 patients with MG who visited hospitals in the Henan Province between January 2010 and February 2014 were included. Age, gender, age at onset, serum antibody, thymus pathology, treatment information, and Myasthenia Gravis Foundation of America (MGFA) classification were assessed. RESULTS: Compared with previous reports from other areas, we found some differences in MG patients from Henan. The proportion of childhood MG in our study was lower than other reports of Oriental patients with MG. There seems to be an association between onset age, muscle involvement, and acetylcholine receptor antibody levels. Thymectomy improved the symptoms in 78.5% of thymectomy-treated patients. CONCLUSIONS: These differences are likely related to geographical, environmental, and ethnic differences. Understanding these differences will help us to define more specific treatment.


Assuntos
Autoanticorpos/imunologia , Debilidade Muscular , Miastenia Gravis/epidemiologia , Receptores Colinérgicos/imunologia , Timo/patologia , Adolescente , Corticosteroides/uso terapêutico , Adulto , Distribuição por Idade , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Azatioprina/uso terapêutico , Criança , Pré-Escolar , China/epidemiologia , Inibidores da Colinesterase/uso terapêutico , Estudos de Coortes , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Imunossupressores/uso terapêutico , Lactente , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/imunologia , Miastenia Gravis/patologia , Miastenia Gravis/terapia , Brometo de Piridostigmina/uso terapêutico , Estudos Retrospectivos , Distribuição por Sexo , Timectomia , Adulto Jovem
15.
Eur Radiol ; 25(2): 568-74, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25257855

RESUMO

OBJECTIVES: To evaluate the incidence and diagnostic performance of reverse attenuation gradient (RAG) sign in patients with coronary stent occlusion. METHODS: We retrospectively included patients with suspected restenosis who underwent both coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) within 2 weeks. Stent occlusion at CCTA was defined as (1) complete contrast filling defect of large calibre stents (at least 3 mm), or (2) presence of RAG sign in patients with small calibre stents (less than 3 mm) or (3) presence of RAG sign in patients with non-diagnostic image quality of stents. The diagnostic performance of RAG sign was further assessed by comparison to ICA results. RESULTS: A total of 162 patients with 231 implanted stents were included. ICA confirmed stent occlusion in 59 patients (99 stents). RAG sign was present in 59.3% (35/59) of all stent occlusions. As shown by patient-based analysis, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of our diagnostic criteria for detection of stent occlusion were 79.7% (47/59), 100% (103/103), 100% (47/47) and 89.6% (103/115) respectively. Superior diagnostic performance was confirmed by receiver operating characteristic (ROC) analysis with an area under the curve of 0.898. CONCLUSIONS: RAG sign observed at CCTA in patients with coronary stenting represents reverse collateral flow distal to stents and is highly specific to indicate stent occlusion. KEY POINTS: • RAG sign in patients with previous stents represents retrograde collateral flow. • RAG sign in patients with previous stents indicates stent occlusion. • RAG sign improves detection of stent occlusion in small calibre stents.


Assuntos
Angiografia Coronária/métodos , Reestenose Coronária/diagnóstico por imagem , Oclusão de Enxerto Vascular/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Stents/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Reestenose Coronária/etiologia , Feminino , Seguimentos , Oclusão de Enxerto Vascular/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos
16.
Cell Biol Int ; 39(9): 1016-25, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25850685

RESUMO

The aim of this study was to determine the correlation between angiogenesis and the differential expression of vascular endothelial growth factor (VEGF) and its receptors in myocardial microvascular endothelial cells (MMVECs) co-cultured with mast cells (MCs) or mast cell granules (MCGs) under oxygen and glucose deprivation (OGD). MMVECs and MCs were isolated from Wistar rats. MCs spontaneously degranulated in OGD. The expression of VEGF peaked at 8 h and decreased from 16 h in OGD. However, the expression of its receptor, fms-like tyrosine kinase-1 (Flt-1), and fetal liver kinase-1 (Flk-1), decreased significantly, and angiogenic potential of MMVECs decreased in OGD. Expression of VEGF, Flt-1, and Flk-1 increased significantly when MMVECs were co-cultured with MCGs or active MCs, but MCs had only a limited ability to induce angiogenesis in OGD. The angiogenic potential of MMVECs cultured in OGD (even with MCGs) was inferior to that of MMVECs cultured under normoxic conditions. OGD have a profound effect on angiogenesis, which is more pronounced than the effect of MCs on angiogenesis.


Assuntos
Células Endoteliais/metabolismo , Glucose/deficiência , Mastócitos/metabolismo , Oxigênio/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Hipóxia Celular/fisiologia , Técnicas de Cocultura , Células Endoteliais/citologia , Glucose/administração & dosagem , Glucose/metabolismo , Miocárdio/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Oxigênio/administração & dosagem , Cultura Primária de Células , Ratos , Ratos Wistar , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo
17.
Int Heart J ; 55(3): 249-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24814326

RESUMO

In addition to contact force (CF), catheter stability is considered to be an important factor in creating radiofrequency lesions.To evaluate the catheter stability during pulmonary vein isolation (PVI) using CF-sensing catheter.PVI was performed in 32 patients using a CF-sensing catheter. Operators were blinded to CF. The application was arbitrarily defined as a "visually unstable" point if the catheter moved ≥ 4 mm. Data were analyzed according to 6 predefined segments for the ipsilateral PVs. As a parameter of catheter stability, the standard deviation (SD) of CF and relative standard deviation (RSD = 100 × SD of CF /average CF) were introduced.A total of 932 RF applications with 426 visually unstable points (UP; 45.7%) and 506 stable points (SP; 54.3%) were analyzed. SD was significantly higher at UP (8.0 g versus 5.7 g, P < 0.001), and RSD was significantly higher at UP (43.7% versus 26.5%, P < 0.001). Higher RSD was associated with visual instability in all the segments of both PVs, however, higher SD of CF was not in all segments. At the antero-superior segment of the LPV, and the roof and posteroinferior segments of the RPV, the RSD values were over 50%, suggesting catheter instability.Catheter instability occurred in 45% of ablations during PVI and was predominantly located in the antero-superior segment of the LPV and postero-inferior segment of the RPV, which may result in incomplete lesion formation. RSD had significant correlation with visual catheter stability.


Assuntos
Fibrilação Atrial/cirurgia , Cateteres Cardíacos/efeitos adversos , Ablação por Cateter/efeitos adversos , Migração de Corpo Estranho/epidemiologia , Sistema de Condução Cardíaco/cirurgia , Veias Pulmonares , Ablação por Cateter/instrumentação , Feminino , Seguimentos , Migração de Corpo Estranho/diagnóstico , Migração de Corpo Estranho/etiologia , Alemanha/epidemiologia , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Incidência , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
18.
J Cardiovasc Electrophysiol ; 24(8): 929-32, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23362986

RESUMO

We report a case of aborted sudden cardiac death and subsequent development of malignant drug-refractory incessant ventricular tachycardia/fibrillation in a patient with acute coronary artery occlusion following radiofrequency ablation within the CS. Catheter ablation is a well-established therapy for treatment of atrial fibrillation (AF). In patients with longstanding persistent AF extensive left atrial ablation and ablation inside the coronary sinus (CS) is frequently performed. Perimitral flutter following AF ablation is the most common form of left atrial macroreentry, especially in patients with previous ablation of complex fractionated electrograms and incomplete linear lesion sets within the left atrium. Successful ablation of this type of tachycardia is generally difficult and in about 60-70% patients requires additional ablation within the CS to achieve termination of tachycardia or/and left atrial isthmus (LAI) block. A limited number of case reports have been published describing acute coronary artery occlusion during or immediately after LAI ablation within the CS. This case exhibits a potential lethal risk of radiofrequency ablation within the CS.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Seio Coronário/cirurgia , Estenose Coronária/complicações , Morte Súbita Cardíaca/prevenção & controle , Taquicardia Ventricular/etiologia , Fibrilação Ventricular/etiologia , Idoso , Reanimação Cardiopulmonar , Angiografia Coronária , Desfibriladores Implantáveis , Humanos , Veias Pulmonares/cirurgia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/prevenção & controle , Fibrilação Ventricular/fisiopatologia , Fibrilação Ventricular/prevenção & controle
19.
Materials (Basel) ; 16(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37444997

RESUMO

To improve the tensile strength and wear resistance of AlSi10Mg alloys, a novel in situ synthesis method of selective laser melting (SLM) was used to fabricate the Ni-reinforced AlSi10Mg samples. The eutectic Si networks formed around the α-Al crystals by diffusion and transportation via Marangoni convection in the SLM process. Moreover, the XRD and TEM results verified that the Al3Ni nanoparticles were created by the in situ reaction of the Ni and aluminum matrix in the Ni/AlSi10Mg samples. Therefore, the microstructure of the Ni-containing alloys was constituted by the α-Al + Si network + Al3Ni phases. The dislocations accumulated at the continuous Si network boundaries and cannot transmit across the dislocation walls inside the Si network. SEM results revealed that the continuity and size of eutectic Si networks can be tailored by adjusting the Ni contents. Furthermore, the Al matrix also benefited from the Al3Ni nanoparticles against the dislocation movement due to their excellent interfacial bonding. The 3Ni-AlSi10Mg sample exhibited high mechanical properties due to the continuous Si networks and Al3Ni nanoparticles. The tensile strength, elongation, Vickers hardness, friction coefficient, and wear volumes of the 3Ni-AlSi10Mg samples were 401.15 ± 7.97 MPa, 6.23 ± 0.252%, 144.06 ± 0.81 HV, 0.608, 0.11 mm3, respectively, which outperformed the pure AlSi10Mg samples (372.05 ± 1.64 MPa, 5.84 ± 0.269%, 123.22 ± 1.18 HV, 0.66, and 0.135 mm3).

20.
Nat Protoc ; 18(2): 555-578, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36333447

RESUMO

Fundamentally understanding the complex electrochemical reactions that are associated with energy devices (e.g., rechargeable batteries, fuel cells and electrolyzers) has attracted worldwide attention. In situ liquid cell transmission electron microscopy (TEM) offers opportunities to directly observe and analyze in-liquid specimens without the need for freezing or drying, which opens up a door for visualizing these complex electrochemical reactions at the nano scale in real time. The key to the success of this technique lies in the design and fabrication of electrochemical liquid cells with thin but strong imaging windows. This protocol describes the detailed procedures of our established technique for the fabrication of such electrochemical liquid cells (~110 h). In addition, the protocol for the in situ TEM observation of electrochemical reactions by using the nanofabricated electrochemical liquid cell is also presented (2 h). We also show and analyze experimental results relating to the electrochemical reactions captured. We believe that this protocol will shed light on strategies for fabricating high-quality TEM liquid cells for probing dynamic electrochemical reactions in high resolution, providing a powerful research tool. This protocol requires access to a clean room equipped with specialized nanofabrication setups as well as TEM characterization equipment.

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