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1.
Nano Lett ; 24(22): 6722-6729, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38717299

RESUMO

Double-layer quantum systems are promising platforms for realizing novel quantum phases. Here, we report a study of quantum oscillations (QOs) in a weakly coupled double-layer system composed of a large-angle twisted-double-bilayer graphene (TDBG). We quantify the interlayer coupling strength by measuring the interlayer capacitance from the QOs pattern at low temperatures, revealing electron-hole asymmetry. At high temperatures when SdHOs are thermally smeared, we observe resistance peaks when Landau levels (LLs) from two moiré minivalleys are aligned, regardless of carrier density; eventually, it results in a 2-fold increase of oscillating frequency in D, serving as compelling evidence of the magneto-intersub-band oscillations (MISOs) in double-layer systems. The temperature dependence of MISOs suggests that electron-electron interactions play a crucial role and the scattering times obtained from MISO thermal damping are correlated with the interlayer coupling strength. Our study reveals intriguing interplays among Landau quantization, moiré band structure, and scatterings.

2.
Nat Commun ; 15(1): 1888, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424092

RESUMO

Stacking order plays a crucial role in determining the crystal symmetry and has significant impacts on electronic, optical, magnetic, and topological properties. Electron-phonon coupling, which is central to a wide range of intriguing quantum phenomena, is expected to be intricately connected with stacking order. Understanding the stacking order-dependent electron-phonon coupling is essential for understanding peculiar physical phenomena associated with electron-phonon coupling, such as superconductivity and charge density waves. In this study, we investigate the effect of stacking order on electron-infrared phonon coupling in graphene trilayers. By using gate-tunable Raman spectroscopy and excitation frequency-dependent near-field infrared nanoscopy, we show that rhombohedral ABC-stacked trilayer graphene has a significant electron-infrared phonon coupling strength. Our findings provide novel insights into the superconductivity and other fundamental physical properties of rhombohedral ABC-stacked trilayer graphene, and can enable nondestructive and high-throughput imaging of trilayer graphene stacking order using Raman scattering.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38387689

RESUMO

Cadmium (Cd) is a highly toxic heavy metal element that might adversely affect sperm function such as the acrosome reaction (AR). Although it is widely recognized that zinc (Zn) plays a crucial role in sperm quality, the complete elucidation of how Zn ameliorates Cd-induced sperm dysfunction is still unclear. In this study, we aimed to explore the protective effects of Zn against the sperm dysfunction induced by Cd in the freshwater crab Sinopotamon henanense. The results demonstrated that Cd exposure not only impaired the sperm ultrastructure, but also caused sperm dysfunction by decreasing the AR induction rate, acrosome enzyme activity, and Ca2+ content in sperm while elevating the activity and transcription expression of key Ca2+ signaling pathway-related proteins Calmodulin (CAM) and Ca2+-ATPase. However, the administration of Zn was found to alleviate Cd-induced sperm morphological and functional disorders by increasing the activity and transcription levels of CaM and Ca2+-ATPase, thereby regulating intracellular Ca2+ homeostasis and reversing the decrease in Ca2+ contents caused by Cd. Furthermore, this study was the first to investigate the distribution of metallothionein (MT) in the AR of S. henanense, and it was found that Zn can reduce the elevated levels of MT in crabs caused by Cd, demonstrating the significance of Zn in inducing MT to participate in the AR process and in metal detoxification in S. henanense. These findings offer novel perspectives and substantiation regarding the utilization of Zn as a protective agent against Cd-induced toxicity and hold significant practical implications for mitigating Cd-induced sperm dysfunction.


Assuntos
Braquiúros , Metais Pesados , Animais , Masculino , Cádmio/metabolismo , Zinco/toxicidade , Metalotioneína/genética , Metalotioneína/metabolismo , Sêmen/metabolismo , Metais Pesados/metabolismo , Espermatozoides , Água Doce , Adenosina Trifosfatases/metabolismo
4.
Int Immunopharmacol ; 127: 111304, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38091826

RESUMO

Acute viral myocarditis can progress to chronic myocarditis leading to dilated cardiomyopathy (DCM). Persistent CD4+ T-cell-mediated autoimmunity triggered by infection plays a critical role in this progression. Increasing evidence demonstrates that effector memory CD4+T (CD4+TEM) cells, a subset of memory CD4+ T cells, are crucial pathogenic mediators of many autoimmune diseases. However, the role of CD4+TEM cells during the progression from acute viral myocarditis to DCM remains unknown. In this study, we observed an increase in CD4+TEM cells both in the periphery and the heart, and memory CD4+ T cells were the predominant sources of IL-17A and IFN-γ among inflamed heart-infiltrating CD4+ T cells during the progression from acute myocarditis to chronic myocarditis and DCM in CVB3-induced BALB/c mice. Moreover, splenic CD4+TEM cells sorted from DCM mice induced by CVB3 were found to respond to cardiac self-antigens ex vivo. Additionally, adoptive transfer experiments substantiated their pathogenic impact, inducing sustained myocardial inflammation, tissue fibrosis, cardiac injury, and impairment of cardiac systolic function in vivo. Our findings illustrate that long-lived CD4+TEM cells are important contributors to the progression from acute viral myocarditis into DCM.


Assuntos
Doenças Autoimunes , Cardiomiopatia Dilatada , Infecções por Coxsackievirus , Miocardite , Camundongos , Animais , Cardiomiopatia Dilatada/patologia , Linfócitos T/patologia , Camundongos Endogâmicos BALB C , Miocárdio/patologia , Infecções por Coxsackievirus/complicações , Enterovirus Humano B
5.
Sensors (Basel) ; 23(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37896502

RESUMO

The direction estimation of the coherent source in a uniform circular array is an essential part of the signal processing area of the array, but the traditional uniform circular array algorithm has a low localization accuracy and a poor localization effect on the coherent source. To solve this problem, this paper proposes a two-dimensional direction of arrival (DOA) estimation for the coherent source in broadband. Firstly, the central frequency of the coherent sound source is estimated using the frequency estimation method of the delayed data, and a real-valued beamformer is constructed using the concept of the multiloop phase mode. Then, the cost function in the beam space is obtained. Finally, the cost function is searched in two dimensions to locate the sound source. In this paper, we simulate the DOA of the sound source at different frequencies and signal-to-noise ratios and analyze the resolution of the circular array. The simulation results show that the proposed algorithm can estimate the direction of arrival with high precision and achieve the desired results.

6.
J Med Virol ; 95(8): e29004, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37526413

RESUMO

Although most patients with acute viral myocarditis recover spontaneously, some patients progress to heart failure. Perturbations in innate immunity may partially explain the heterogeneity of clinical outcomes. As the most abundant immune cells in the heart, cardiac macrophages have heterogeneous origins, including embryonic-derived resident macrophages (ResMϕs) and monocyte-derived macrophages (MoMFs). However, the time course change and role of cardiac macrophage subsets has not been fully explored. In the present study, we found that BALB/c mice had prolonged MoMF accumulation and low proportions of ResMϕs that could not be restored to normal levels. MoMFs of BALB/c mice generally exhibit an M1-dominant functional phenotype. Moreover, the preferential depletion of MoMF by a C-C chemokine receptor type 2 (CCR2) inhibitor resulted in improved acute myocarditis and chronic fibrosis, as well as the recovery of ResMϕs number and reduced CD4+ T cell expansion. Hence, immunomodulatory therapy that targets the balance among cardiac macrophages and modulates their function is expected to prevent the progression of cardiac injury to overt heart failure and improve adverse outcomes.


Assuntos
Infecções por Coxsackievirus , Insuficiência Cardíaca , Miocardite , Camundongos , Animais , Enterovirus Humano B/fisiologia , Coração , Macrófagos
7.
BMC Cardiovasc Disord ; 22(1): 78, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246021

RESUMO

BACKGROUND: The aberrant distribution of peripheral B cell subsets is associated with the pathogenesis of a variety of inflammatory and autoimmune diseases. However, the distribution of peripheral B cell subsets in patients with idiopathic dilated cardiomyopathy (DCM) remains to be elucidated. METHODS: Twenty-seven patients with idiopathic DCM (DCM group), 18 control patients with heart failure (HF group) and 21 healthy individuals (HC group) were included in this study. Peripheral B cell subsets were analysed using multicolour flow cytometry. The plasma ß1 adrenergic receptor (ß1-AR) autoantibody titre was determined using ELISA. Additionally, clinical features were also collected. RESULTS: Compared with the HF and HC groups, the percentage of B1 cells was significantly decreased, whereas the percentage of transitional B cells (Tr) was significantly increased in the DCM group. Notably, the percentage of B1 cells was significantly lower in patients with ß1-AR autoantibody-positive DCM than in ß1-AR autoantibody-negative patients. The correlation analysis showed that the percentage of B1 cells was negatively correlated with N-terminal pro-brain natriuretic peptide (NT-proBNP) levels and positively correlated with the left ventricular ejection fraction in patients with DCM. CONCLUSION: As shown in the present study, the percentage of B1 cells in the peripheral blood of patients with idiopathic DCM is abnormally decreased, especially in ß1-AR autoantibody-positive patients, while the percentage of Tr cells is significantly increased, indicating that B1 cells and Tr cells may be implicated in the pathogenesis of idiopathic DCM. The decrease in the percentage of B1 cells is directly related to the severity of DCM.


Assuntos
Subpopulações de Linfócitos B , Cardiomiopatia Dilatada , Autoanticorpos , Subpopulações de Linfócitos B/patologia , Cardiomiopatia Dilatada/complicações , Humanos , Projetos Piloto , Células Precursoras de Linfócitos B/patologia , Volume Sistólico , Função Ventricular Esquerda
8.
J Phys Chem Lett ; 13(10): 2299-2305, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35244399

RESUMO

Band structure dictates optical and electronic properties of solids and eventually the efficiency of the semiconductor based solar conversion. Compared to numerous theoretical calculations, the experimentally measured band structure of rutile TiO2, a prototypical photocatalytic material, is rare. In this work, the valence band structure of rutile TiO2(110) is measured by angle-resolved photoelectron spectroscopy using polarized extreme ultraviolet light. The effective mass of the hole, which has never been measured before, is determined to be 4.66-6.87 m0 (free electron mass) and anisotropic. The dependence of photoemission intensities on excitation light polarization is analyzed by taking into account of the parity symmetry of molecular orbitals in the blocking unit of rutile TiO2. This work reports a direct measurement of valence band structure and hole effective mass of rutile TiO2(110), which will deepen our understanding of the electronic structure and charge carrier properties of the model material and provide reference data for future theoretical calculations.

9.
Clin Exp Immunol ; 208(1): 1-11, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35262174

RESUMO

Although B cells are essential for humoral immunity and show noteworthy immunomodulatory activity through antibody-independent functions, the role of B cells in regulating Treg cell responses remains controversial. Tregs (CD4+CD25+Foxp3+) are considered to play an immunoprotective role in viral myocarditis (VMC) by controlling autoimmune effector T cells. Here, we proved that B-cell knockout can not only lead to significant reductions in Tregs in the spleen, blood, and heart of VMC mice but also decrease the activation and immune function of splenic Tregs, which was reversed by adoptive transfer of B cells; the transcription levels of TGF-ß and Foxp3 in the myocardium were also significantly reduced. B-cell depletion by anti-CD20 impaired the anti-inflammatory function of splenic Tregs and the homeostasis of myocardial Tregs population. Moreover, B cells can convert CD4+CD25- T cells into Foxp3+ and Foxp3-, two functionally suppressive Treg subgroups. Although the reduction in myocardial inflammation in BKO mice indicates that B cells may play a proinflammatory role, the beneficial side of B cells cannot be ignored, that is, to control autoimmunity by maintaining Treg numbers. The results observed in the animal model of VMC highlight the potential harm of rituximab in the nonselective depletion of B cells in clinical applications.


Assuntos
Miocardite , Camundongos , Animais , Linfócitos T Reguladores , Miocárdio , Transferência Adotiva , Linfócitos B , Fatores de Transcrição Forkhead , Camundongos Endogâmicos C57BL
10.
Nano Lett ; 22(5): 2065-2069, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35192357

RESUMO

The large tolerance of hybrid perovksites to the trapping of electrons by defects is a key asset in photovoltaic applications. Here, the ionic surface terminations of CH3NH3PbI3 are employed as a testbed to study the effect of electrostatic fields on the dynamics of excited carriers. We characterize the transition across the tetragonal to orthorhombic phase. The observed type II band offset and drift of the excited electrons highlight the important role that organic cations have on the screening of local electrostatic fields. When the orientation of organic cations is frozen in the orthorhombic phase, the positively charged termination induces a massive accumulation of excited electrons at the surface of the sample. Conversely, no electron accumulation is observed in the tetragonal phase. We conclude that the local fields cannot penetrate in the sample when the polarizability of freely moving cations boosts the dielectric constant up to ε = 120.

11.
Chemosphere ; 289: 133240, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34896422

RESUMO

Until now, knowledge about the interactive effects of microplastics and environmental factors on primary producers is quite limited. In this work, a marine diatom (Phaeodactylum tricornutum) was exposed to polymethyl methacrylate (PMMA) microplastics at different salinities (25, 35, and 45‰) for 10 days in order to study their interactive effects. Results showed that growth of P. tricornutum was negatively affected by PMMA microplastics and salinity variation with a minimum EC50 value of 91.75 mg L-1. Photosynthetic activity of P. tricornutum was also inhibited by the two factors, and their interactive effects on chlorophyll fluorescence parameters (Fv/Fm and ΦPSII) were significant. In the algal cells, soluble protein accumulated, activities of two antioxidant enzymes changed, and malondialdehyde (MDA) content increased when this diatom was exposed to the microplastics at different salinities. These data would help to evaluate the risks of microplastics to primary producers under different environmental factors.


Assuntos
Diatomáceas , Microplásticos , Plásticos/toxicidade , Polimetil Metacrilato/toxicidade , Salinidade
12.
Ecotoxicol Environ Saf ; 227: 112915, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34687943

RESUMO

In a previous study, silkworm larvae were used as a novel model to assess the biotoxicity of ILs, which showed that ILs could cause significant physiological and biochemical changes in midguts and silk glands of the larvae, and result in the death of larvae. In order to investigate the toxicity of 1-octyl-3-methylimidazole chloride ([C8mim]Cl) to the larvae at molecular level, RNA-sequencing technology was used to construct transcriptomic profiles of midguts and silk glands in this work. Results showed that a lot of differentially expressed genes (DEGs) were effectively screened out through bioinformatics software based on the transcriptome data and reference genome. To give more detail, 5118 and 2211 DEGs (926 and 822 DEGs) were obtained in the midguts (silk glands) when the larvae were exposed to [C8mim]Cl for 6 and 12 h, respectively, relative to the controls. In addition, gene ontology (GO) analysis suggested that the DEGs could be divided into three categories (i.e., biological process, cellular component, and molecular function), and were involved in multiple organelle functions and complex biological processes. Kyoto encyclopedia of genes and genomes (KEGG) analysis showed that the DEGs were enriched in a variety of pathways, such as signal transduction, apoptosis, glycolysis, peroxisome, autophagy, hippo signaling pathway, arginine and proline metabolism. Results of quantitative real-time PCR and histopathological observation indicated that molecular mechanism of the larvae against [C8mim]Cl toxicology may be attributed to cell apoptosis regulation via both the mitochondrial pathway and the death receptor-initiated pathway. Thus, these results provided useful data for exploring the toxicity of ILs to insects at molecular level.


Assuntos
Bombyx , Animais , Bombyx/genética , Cloretos , Perfilação da Expressão Gênica , Seda/genética , Transcriptoma
13.
Water Sci Technol ; 83(11): 2615-2628, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34115617

RESUMO

Previous studies have documented that Chlorella sorokiniana could grow well on cooking cocoon wastewater (CCW) with a maximum biomass of 0.49 g/L. In order to further enhance the biomass production and nutrient removals, a bubble-column bioreactor was designed and performed to cultivate C. sorokiniana in CCW, and two main cultivation parameters were investigated in this work. Results showed that a maximum algal biomass, specific growth rate, and biomass productivity of 2.83 g/L, 0.854 d-1, and 476.25 g/L/d, respectively, were achieved when this alga was cultivated in the bioreactor with an initial cell density of 0.8 g/L and an aeration rate of 3.34 L air/L culture/min; meanwhile, removal efficiencies of ammonium, total nitrogen, total phosphorus, and chemical oxygen demand reached 97.96, 85.66, 97.96, and 86.43%, respectively, which were significantly higher than that obtained in our previous studies. Moreover, chemical compositions in the algal cells varied with the changes of cultivation conditions (i.e., initial cell density and aeration rate). Thus, it is concluded that (1) the bubble-column bioreactor was suitable for cultivation of C. sorokiniana coupled with the CCW treatment and (2) initial cell density and aeration rate affected the biomass production, nutrient removals and chemical compositions of this alga.


Assuntos
Chlorella , Microalgas , Biomassa , Reatores Biológicos , Contagem de Células , Culinária , Nitrogênio , Águas Residuárias
14.
Mar Pollut Bull ; 166: 112222, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33711610

RESUMO

A marine diatom (Phaeodactylum tricornutum) was exposed to different concentrations of dimethyl phthalate (DMP) and diethyl phthalate (DEP) for 96 h within a batch-culture system to investigate their toxicities. Results showed that P. tricornutum could remove DMP and DEP effectively with removal rates of 0.20-0.30 and 0.14-0.21 mg L-1 h-1, respectively. In addition, DMP and DEP significantly inhibited the photosynthesis and chlorophyll a biosynthesis of P. tricornutum with 96-h EC50 values of 390.5 mg L-1 and 74.0 mg L-1, respectively. Results of reactive oxygen species (ROS) level suggested that the two PAEs could induce excessive ROS production in the diatom. Moreover, activities of antioxidant enzymes (i.e., SOD and POD) in the diatom increased with the increase of DMP and DEP concentrations. The results will help to understand the toxic mechanisms of PAEs, and provide strong evidences for evaluating their ecological risks in the marine environment.


Assuntos
Diatomáceas , Ácidos Ftálicos , Clorofila A , Ésteres , Estresse Oxidativo , Ácidos Ftálicos/toxicidade
15.
Ecotoxicol Environ Saf ; 209: 111759, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341695

RESUMO

Ionic liquids (ILs) have been reported to be a potential water and soil pollutant, whose toxicity has gained much attention in recent years. In this work, silkworm larvae were used as a novel in vivo model to assess the biotoxicity of ILs, which were performed by three steps. The first step was to determine the susceptibility of different silkworm strains to ILs. Data showed that Jingsong×haoyue was the most susceptible one among three silkworm strains (Jingsong×haoyue, P50, and Yi16) for evaluating the biological effects of ILs. The second step was to compare the toxicity of ILs with different structures using the larvae of Jingsong×haoyue. It was found that three representative ILs, 1-octyl-3-methylimidazole chloride ([C8mim]Cl), N-octyl-3-methylpyridine chloride ([C8mpy]Cl), and 1-octyl-3-methylimidazole tetrafluoroborate ([C8mim]BF4), had significant toxic effects on the growth and development of the larvae with 24 h median lethal concentration (24 h-LC50) values of 112.3, 156.3, and 68.9 µg g-1, respectively, indicating that the types of anions and cations had impacts on the toxicity of ILs. The last step was targeted at investigating responses of the larvae to the exposure of ILs. It was observed that remarkable physiological and biochemical responses occurred in different tissues of the larvae. For example, activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) in different tissues increased significantly to form an active protective mechanism for alleviating the toxic effects of ILs. Additionally, an increase of malondialdehyde (MDA) contents was found in the larvae. The data suggested that ILs could induce lipid peroxidation and cellular damage, which may be the main reason for toxicity of ILs to the larvae. Therefore, silkworm larvae could be used as a susceptible and reliable in vivo model to evaluate the toxicity of ILs, and the results are helpful to reveal their toxic mechanism to insects.


Assuntos
Substâncias Perigosas/toxicidade , Líquidos Iônicos/toxicidade , Animais , Ânions/química , Bombyx/metabolismo , Bombyx/fisiologia , Catalase/metabolismo , Cátions , Cloretos , Estudos de Viabilidade , Imidazóis , Larva/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído , Superóxido Dismutase/metabolismo , Testes de Toxicidade
16.
Proc Natl Acad Sci U S A ; 117(36): 21962-21967, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32848070

RESUMO

Two-dimensional electron gases (2DEGs) are at the base of current nanoelectronics because of their exceptional mobilities. Often the accumulation layer forms at polar interfaces with longitudinal optical (LO) modes. In most cases, the many-body screening of the quasi-2DEGs dramatically reduces the Fröhlich scattering strength. Despite the effectiveness of such a process, it has been recurrently proposed that a remote coupling with LO phonons persists even at high carrier concentration. We address this issue by perturbing electrons in an accumulation layer via an ultrafast laser pulse and monitoring their relaxation via time- and momentum-resolved spectroscopy. The cooling rate of excited carriers is monitored at doping level spanning from the semiconducting to the metallic limit. We observe that screening of LO phonons is not as efficient as it would be in a strictly 2D system. The large discrepancy is due to the remote coupling of confined states with the bulk. Our data indicate that the effect of such a remote coupling can be mimicked by a 3D Fröhlich interaction with Thomas-Fermi screening. These conclusions are very general and should apply to field effect transistors (FET) with high-κ dielectric gates, van der Waals heterostructures, and metallic interfaces between insulating oxides.

17.
Ecotoxicol Environ Saf ; 198: 110604, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32339924

RESUMO

With the extensive use of ionic liquids (ILs) in various industrial fields, their potential toxicity to aquatic ecosystem has attracted considerable attention. In this work, biotoxicity of ILs with different cations and anions was evaluated by using a freshwater green alga Chlorella pyrenoidosa. Results showed that 1-butyl-3-methylimidazolium chloride ([C4mim]Cl), 1-octyl-3-methylimidazolium chloride ([C8mim]Cl), 1-octyl-3-methylimidazolium nitrate ([C8mim]NO3), 1-octyl-3-methylimidazolium tetrafluoroborate ([C8mim]BF4), and 1-dodecyl-3-methylimidazolium chloride ([C12mim]Cl) had a significant inhibition on the algal growth with EC50 values of 23.48, 4.72, 3.80, 4.44, and 0.10 mg L-1 at the 72 h of exposure, respectively. These data suggested that the toxicity of ILs increased with the increase of side alkyl chain length, while anions had little influences on their toxicity to this alga. Moreover, changes in chlorophyll a content and chlorophyll fluorescence parameters (Fv/Fm and ΦPSII) indicated that the five ILs could damage the photosynthetic system of this alga resulting in the decrease of photosynthetic efficiency. The increased soluble protein content and antioxidase activity could be considered as an active response mechanism of this alga against the exposure of ILs. Content of malondialdehyde (MDA) in this alga increased significantly when it was exposed to ILs, suggesting that reactive oxygen species (ROS) were accumulated in the algal cells, which would cause injury of the algal biofilm and chloroplast. Therefore, results obtained in this work would help to explain the possible underlying toxic mechanisms of ILs to C. pyrenoidosa, and provide a significant theoretical support for assessing the toxicity of ILs to aquatic organisms.


Assuntos
Ânions/toxicidade , Cátions/toxicidade , Chlorella/efeitos dos fármacos , Líquidos Iônicos/toxicidade , Testes de Toxicidade , Ânions/química , Cátions/química , Clorofila A/metabolismo , Cloroplastos/efeitos dos fármacos , Ecossistema , Água Doce , Crescimento/efeitos dos fármacos , Imidazóis/toxicidade , Líquidos Iônicos/química , Fotossíntese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
18.
Oncol Rep ; 42(6): 2855, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31661140

RESUMO

Subsequently to the publication of this paper, the authors have realized that the affilitation address omitted the name of the university at which this research was conducted (Capital Medical University). Therefore, the author affiliations for this paper should have appeared as follows (changes are highlighted in bold): JINGWEI DONG and MINGJUN XU.Department of Anesthesiology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing 100001, P.R. China. The authors regret that the name of the university was not included with the paper prior to its publication, and apologize to the readers for any inconvenience caused. [the original article was published in Oncology Reports 41: 3233­3243, 2019; DOI: 10.3892/or.2019.7108].

19.
Med Sci Monit ; 25: 3100-3107, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31028241

RESUMO

BACKGROUND The aim of this study was to investigate the effects of sevoflurane (SEV) on myocardial ischemia/reperfusion (I/R) injury in rats and its mechanism. MATERIAL AND METHODS Sixty male Sprague-Dawley rats were randomly divided into 3 groups: Sham group (n=20), I/R group (n=20) and I/R+SEV group (n=20). The I/R model was established by ligating and recanalizing the left anterior descending coronary artery (LAD). Triphenyl tetrazolium chloride (TTC) test and echocardiography (ECG) were used for analysis. Hematoxylin and eosin (H&E) staining was applied to detect the morphological changes. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was conducted to detect the apoptosis levels. The expression level of superoxide dismutase 2 (SOD2) was measured. Finally, the effect of SEV on the protein kinase B (Akt)/hypoxia-inducible factor 1-alpha (HIF-1alpha)/vascular endothelial growth factor (VEGF) signaling pathway was detected via western blotting. RESULTS SEV could significantly improve I/R-induced cardiac insufficiency, inhibit cardiac infarction, and as well as reduce the infarction area from 53.21±2.11% to 32.33±3.49% (P<0.05). Compared with rats in I/R group, the cardiac myofilament was better in alignment, degradation and necrosis were milder, and cell edema was notably reduced in the I/R+SEV group. Thus, SEV could significantly reverse the decreased expression of SOD2 caused by I/R and reduce oxidative stress in the heart (P<0.05). According to the western blotting results, SEV was capable of obviously activating the expressions of phosphorylated-Akt (p-Akt), HIF-1alpha, and VEGF. CONCLUSIONS SEV can significantly improve myocardial injury caused by I/R in rats, and its mechanism might be related to the activation of the Akt/HIF-1alpha/VEGF signaling pathway.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sevoflurano/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Apoptose/efeitos dos fármacos , Masculino , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/metabolismo , Reperfusão Miocárdica/métodos , Traumatismo por Reperfusão Miocárdica/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
20.
Oncol Rep ; 41(6): 3233-3243, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31002358

RESUMO

Ovarian cancer (OC) is the most common gynecologic malignancy with high incidence and mortality. The present study aimed to develop approaches for determining the recurrence type and identify potential miRNA markers for OC prognosis. The miRNA expression profile of OC (the training set, including 390 samples with recurrence information) was downloaded from The Cancer Genome Atlas database. The validation sets GSE25204 and GSE27290 were obtained from the Gene Expression Omnibus database. Prescreening of clinical factors was conducted using the survival package, and the differentially expressed miRNAs (DE­miRNAs) were identified using the limma package. Using the Caret package, the optimal miRNA set was selected to build a Support Vector Machine (SVM) classifier. The miRNAs and clinical factors independently related to prognosis were analyzed using the survival package, and the risk score system was constructed. Finally, the miRNA­target regulatory network was built by Cytoscape software, and enrichment analysis was performed. There were 46 DE­miRNAs between the recurrent and non­recurrent samples. After the optimal 19­miRNA set was selected for constructing the SVM classifier, 6 DE­miRNAs (miR­193b, miR­211, miR­218, miR­505, miR­508 and miR­514) independently related to prognosis were further extracted to build the risk score system. The neoplasm cancer status was independently correlated with the prognosis and conducted with stratified analysis. Additionally, the target genes in the regulatory network were enriched in the regulation of actin cytoskeleton and the TGF­ß signaling pathway. The 6­miRNA signature may serve as a potential biomarker for OC prognosis, particularlyfor recurrence.


Assuntos
MicroRNAs/genética , Recidiva Local de Neoplasia/genética , Neoplasias Ovarianas/genética , Prognóstico , Biologia Computacional , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Humanos , MicroRNAs/classificação , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/classificação , Recidiva Local de Neoplasia/patologia , Neoplasias Ovarianas/classificação , Neoplasias Ovarianas/patologia , Fatores de Risco , Máquina de Vetores de Suporte
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