Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Mol Cell ; 81(22): 4579-4590, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34562371

RESUMO

Canonically, gasdermin D (GSDMD) cleavage by caspase-1 through inflammasome signaling triggers immune cell pyroptosis (ICP) as a host defense against pathogen infection. However, cancer cell pyroptosis (CCP) was recently discovered to be activated by distinct molecular mechanisms in which GSDMB, GSDMC, and GSDME, rather than GSDMD, are the executioners. Moreover, instead of inflammatory caspases, apoptotic caspases and granzymes are required for gasdermin protein cleavage to induce CCP. Sufficient accumulation of protease-cleaved gasdermin proteins is the prerequisite for CCP. Inflammation induced by ICP or CCP results in diametrically opposite effects on antitumor immunity because of the differential duration and released cellular contents, leading to contrary effects on therapeutic outcomes. Here, we focus on the distinct mechanisms of ICP and CCP and discuss the roles of ICP and CCP in inflammation and antitumor immunity, representing actionable targets.


Assuntos
Antineoplásicos/farmacologia , Inflamação , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/imunologia , Neoplasias/terapia , Proteínas de Ligação a Fosfato/metabolismo , Piroptose , Animais , Apoptose , Caspases/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Sistema Imunitário , Inflamassomos , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos/metabolismo , Camundongos , Neoplasias/metabolismo , Ligação Proteica , Proteólise , Transdução de Sinais
2.
Semin Immunol ; 70: 101833, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37647772

RESUMO

The identification of gasdermin as the executor of pyroptosis has opened new avenues for the study of this process. Although pyroptosis research has mainly focused on immune cells since it was discovered three decades ago, accumulating evidence suggests that pyroptosis plays crucial roles in many biological processes. One example is the discovery of gasdermin-mediated cancer cell pyroptosis (CCP) which has become an important and frontier field in oncology. Recent studies have shown that CCP induction can heat tumor microenvironment (TME) and thereby elicit the robust anti-tumor immunity to suppress tumor growth. As a newly discovered form of tumor cell death, CCP offers promising opportunities for improving tumor treatment and developing new drugs. Nevertheless, the research on CCP is still in its infancy, and the molecular mechanisms underlying the expression, regulation and activation of gasdermins are not yet fully understood. In this review, we summarize the recent progress of gasdermin research in cancer area, and propose that the anti-tumor effect of immune cell pyroptosis (ICP) and CCP depends on their duration, intensity, and the type of cells undergoing pyroptosis within TME.


Assuntos
Gasderminas , Neoplasias , Humanos , Neoplasias/terapia , Carcinogênese , Microambiente Tumoral , Piroptose
3.
Molecules ; 28(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36985844

RESUMO

The Second Oil Production Plant of Xinjiang Oilfield produces a large amount of highly emulsified crude oil, which has a serious impact on the subsequent oil-water separation. At present, the concentration of demulsifier has increased to 2000 mg/L, but the demulsification effect is still poor. In this paper, the source and physical properties of highly emulsified crude oil are investigated firstly. The results show that highly emulsified crude oil is composed of three kinds of liquid: (1) conventional water flooding (WF); (2) chemical flooding (CF); (3) fracturing backflow fluid (FB). Among them, high zeta potential, low density difference, high viscosity, and small emulsion particles are responsible for the difficulty in the demulsification of the WF emulsion, while the high pH value is the reason why the CF emulsion is difficult to demulsify. Therefore, systematic experiments were implemented to investigate the optimal demulsification approach towards the three liquids above. As for the WF emulsion, it was necessary to raise the temperature to 70 °C and the concentration of the demulsifier to 200 mg/L. Moreover, it was only necessary to add 200 mg/L of demulsifier to break the CF emulsion after adjusting the pH value to 7, while no extra treatments were needed to break the FB emulsion. We hope this study can provide a new insight for the treatment of emulsions in the later stage of oilfield development.

4.
Sensors (Basel) ; 21(21)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34770329

RESUMO

Laser-induced graphene (LIG) has been widely used in flexible sensors due to its excellent mechanical properties and high conductivity. In this paper, a flexible pressure sensor prepared by bionic micro/nanostructure design and LIG mass fraction regulation is reported. First, prepared LIG and conductive carbon paste (CCP) solutions were mixed to obtain a conductive polymer. After the taro leaf structure was etched on the surface of the aluminum alloy plate by Nd:YAG laser processing, the conductive polymer was evenly coated on the template. Pressure sensors were packaged with a stencil transfer printing combined with an Ecoflex flexible substrate. Finally, the effects of different laser flux and the proportion of LIG in the composite on the sensitivity of the sensor are discussed. The results show that when the laser flux is 71.66 J·cm-2 and the mass fraction of LIG is 5%, the sensor has the best response characteristics, with a response time and a recovery time of 86 ms and 101 ms, respectively, with a sensitivity of 1.2 kPa-1 over a pressure range of 0-6 kPa, and stability of 650 cycle tests. The LIG/CCP sensor with a bionic structure demonstrates its potential in wearable devices.


Assuntos
Grafite , Nanoestruturas , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Lasers
5.
Anal Bioanal Chem ; 412(13): 3063-3071, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32215690

RESUMO

Clopidol is one of the most widely used anti-coccidiosis drugs. Its residues in poultry products and the environment pose a serious threat to human health. In this work, microwave-assisted synthesis of magnetic ionic liquid/gold nanoparticles (MIL-Au NPs) as the SERS substrates were first designed for sensitive and reliable determination of clopidol residue in egg samples. The experiment shows that MIL(1-methyl-3-hexyl imidazole ferric tetrachloride ([C6mim]FeCl4)) and microwave play a key role in the dispersion and morphology of Au NPs. Under the optimal conditions, the as-prepared MIL-Au NPs were applied to the SERS detection of clopidol in methanol and egg solution and its detection limits can be as low as to 0.5 µg/kg (equal to 0.5 ppb) in both solutions. The standard curves with regression coefficients of 0.9298 and 0.93496 were constructed in the linear range of 100-1000 ppb and 0.5-50 ppb for clopidol in egg solutions. Moreover, satisfactory recoveries (97.5-103.2%) were obtained for egg samples. The developed SERS method provides a way for quantitation of clopidol and can be applied for the convenient, reliable, and highly sensitive detection of antibiotic residues in food and environment, which has great potential in food safety and biological monitoring. Graphical abstract.


Assuntos
Clopidol/análise , Coccidiostáticos/análise , Ouro/química , Líquidos Iônicos/síntese química , Nanopartículas Metálicas/química , Micro-Ondas , Análise Espectral Raman/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
6.
J Nanosci Nanotechnol ; 18(5): 3709-3712, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442888

RESUMO

CdS nanowires arrays were successfully synthesized by a simple solvothermal process using AAO as templates. The phase structures, morphologies, and optical properties of the products were investigated by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Raman spectroscopy, and photoluminescence spectroscopy. It was found that the nanowires were composed of hexagonal structure CdS nanoparticles and the average diameters is about 60-70 nm. A strong green emission with a maximum around 505 nm was observed from the synthesized CdS nanowires at room temperature, which was attributed to near-band-edge emission. A 3D self-seed nucleation coalescent process was proposed for the formation of CdS nanowires structures. The present synthetic route is expected to be applied to the synthesis of other II-VI groups or other group's 1D semiconducting materials.

7.
Int J Cancer ; 137(3): 512-24, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25546612

RESUMO

HER2 receptor dimerization is a critical step in the HER2 activation process. Here, we demonstrated that heat shock protein gp96 on cell membrane interacts with HER2, facilitates HER2 dimerization and promotes cell proliferation. Cell membrane gp96 levels were observed to correlate with HER2 phosphorylation in primary breast tumors. Finally, we provide evidence that targeting gp96 with a specific monoclonal antibody led to decreased cell growth and increased apoptosis in vitro, and suppression of tumor growth in vivo. Our work represents a new therapeutic strategy for inhibiting HER2 signaling in cancer.


Assuntos
Neoplasias da Mama/metabolismo , Glicoproteínas de Membrana/metabolismo , Multimerização Proteica , Receptor ErbB-2/metabolismo , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Transformada , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Proliferação de Células , Modelos Animais de Doenças , Feminino , Expressão Gênica , Xenoenxertos , Humanos , Isoenxertos , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Fosforilação , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/química , Receptor ErbB-2/genética , Transdução de Sinais , Carga Tumoral
8.
J Clin Invest ; 134(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37883181

RESUMO

Several poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) are approved by FDA to treat cancer with BRCA mutations. BRCA mutations are considered to fuel a PARPi killing effect by inducing apoptosis. However, resistance to PARPi is frequently observed in the clinic due to an incomplete understanding on the molecular basis of PARPi function and a lack of good markers, beyond BRCA mutations, to predict response. Here, we show that gasdermin C (GSDMC) sensitized tumor cells to PARPi in vitro and in immunocompetent mice and caused durable tumor regression in an immune-dependent manner. A high expression level of GSDMC predicted better response to PARPi treatment in patients with triple-negative breast cancer (TNBC). PARPi treatment triggered GSDMC/caspase-8-mediated cancer cell pyroptosis (CCP) that enhanced PARPi killing of tumor cells. GSDMC-mediated CCP increased memory CD8+ T cell population in lymph node (LN), spleen, and tumor and, thus, promoted cytotoxic CD8+ T cell infiltration in the tumor microenvironment. T cell-derived granzyme B (GZMB) activated caspase-6, which subsequently cleaved GSDMC to induce pyroptosis. Interestingly, IFN-γ induced GSDMC expression, which, in turn, enhanced the cytotoxicity of PARPi and T cells. Importantly, GSDMC promoted tumor clearance independent of BRCA deficiency in multiple cancer types with PARPi treatment. This study identifies a general marker and target for PARPi therapy and offers insights into the mechanism of PARPi function.


Assuntos
Neoplasias , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Animais , Camundongos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Gasderminas , Neoplasias/genética , Apoptose , Piroptose , Microambiente Tumoral , Biomarcadores Tumorais/genética
9.
Nanomaterials (Basel) ; 14(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38470802

RESUMO

The release of organic contaminants has grown to be a major environmental concern and a threat to the ecology of water bodies. Persulfate-based Advanced Oxidation Technology (PAOT) is effective at eliminating hazardous pollutants and has an extensive spectrum of applications. Iron-based metal-organic frameworks (Fe-MOFs) and their derivatives have exhibited great advantages in activating persulfate for wastewater treatment. In this article, we provide a comprehensive review of recent research progress on the significant potential of Fe-MOFs for removing antibiotics, organic dyes, phenols, and other contaminants from aqueous environments. Firstly, multiple approaches for preparing Fe-MOFs, including the MIL and ZIF series were introduced. Subsequently, removal performance of pollutants such as antibiotics of sulfonamides and tetracyclines (TC), organic dyes of rhodamine B (RhB) and acid orange 7 (AO7), phenols of phenol and bisphenol A (BPA) by various Fe-MOFs was compared. Finally, different degradation mechanisms, encompassing free radical degradation pathways and non-free radical degradation pathways were elucidated. This review explores the synthesis methods of Fe-MOFs and their application in removing organic pollutants from water bodies, providing insights for further refining the preparation of Fe-MOFs.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124592, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-38861826

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease with multiple symptoms, and its rapid screening is the research focus of surface-enhanced Raman scattering (SERS) technology. In this study, gold@silver-porous silicon (Au@Ag-PSi) composite substrates were synthesized by electrochemical etching and in-situ reduction methods, which showed excellent sensitivity and accuracy in the detection of rhodamine 6G (R6G) and serum from SLE patients. SERS technology was combined with deep learning algorithms to model serum features using selected CNN, AlexNet, and RF models. 92 % accuracy was achieved in classifying SLE patients by CNN models, and the reliability of these models in accurately identifying sera was verified by ROC curve analysis. This study highlights the great potential of Au@Ag-PSi substrate in SERS detection and introduces a novel deep learning approach for SERS for accurate screening of SLE. The proposed method and composite substrate provide significant value for rapid, accurate, and noninvasive SLE screening and provide insights into SERS-based diagnostic techniques.


Assuntos
Aprendizado Profundo , Ouro , Lúpus Eritematoso Sistêmico , Prata , Análise Espectral Raman , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/diagnóstico , Análise Espectral Raman/métodos , Humanos , Ouro/química , Prata/química , Rodaminas/química , Silício/química , Feminino , Algoritmos , Nanopartículas Metálicas/química , Adulto
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124178, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38565050

RESUMO

The development of a highly sensitive, synthetically simple and economical SERS substrate is technically very important. A fast, economical, sensitive and reproducible CuNPs@AgNPs@ Porous silicon Bragg reflector (PSB) SERS substrate was prepared by electrochemical etching and in situ reduction method. The developed CuNPs@AgNPs@PSB has a large specific surface area and abundant "hot spot" region, which makes the SERS performance excellent. Meanwhile, the successful synthesis of CuNPs@AgNPs can not only modulate the plasmon resonance properties of nanoparticles, but also effectively prolong the time stability of Cu nanoparticles. The basic performance of the substrate was evaluated using rhodamine 6G (R6G). (Detection limit reached 10-15 M, R2 = 0.9882, RSD = 5.3 %) The detection limit of Forchlorfenuron was 10 µg/L. The standard curve with a regression coefficient of 0.979 was established in the low concentration range of 10 µg/L -100 µg/L. This indicates that the prepared substrates can accomplish the detection of pesticide residues in the low concentration range. The prepared high-performance and high-sensitivity SERS substrate have a very promising application in detection technology.


Assuntos
Nanopartículas Metálicas , Compostos de Fenilureia , Piridinas , Rodaminas , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Prata/química
12.
Nat Commun ; 15(1): 3149, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605037

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) develops through step-wise genetic and molecular alterations including Kras mutation and inactivation of various apoptotic pathways. Here, we find that development of apoptotic resistance and metastasis of KrasG12D-driven PDAC in mice is accelerated by deleting Plk3, explaining the often-reduced Plk3 expression in human PDAC. Importantly, a 41-kDa Plk3 (p41Plk3) that contains the entire kinase domain at the N-terminus (1-353 aa) is activated by scission of the precursor p72Plk3 at Arg354 by metalloendopeptidase nardilysin (NRDC), and the resulting p32Plk3 C-terminal Polo-box domain (PBD) is removed by proteasome degradation, preventing the inhibition of p41Plk3 by PBD. We find that p41Plk3 is the activated form of Plk3 that regulates a feed-forward mechanism to promote apoptosis and suppress PDAC and metastasis. p41Plk3 phosphorylates c-Fos on Thr164, which in turn induces expression of Plk3 and pro-apoptotic genes. These findings uncover an NRDC-regulated post-translational mechanism that activates Plk3, establishing a prototypic regulation by scission mechanism.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo
13.
J Virol ; 86(22): 12465, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23087122

RESUMO

Through routine and nested PCR amplifications, four complete genome sequences of porcine Torque teno virus (TTV) type II were obtained from swine herds. By comparison with the TTV genome sequences deposited in GenBank, we found the most divergent types so far described. The level of genetic diversity between these genomes is higher than would be expected within a single virus species. A nucleotide and amino acid phylogenetic tree was constructed.


Assuntos
Genoma Viral , Torque teno virus/genética , Animais , DNA Viral , Bases de Dados Genéticas , Genes Virais , Variação Genética , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Suínos
14.
J Virol ; 86(21): 11953, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23043181

RESUMO

Here, we report three complete genome sequences of porcine torque teno virus type I (TTV1) which were obtained from swine tissues and sera from southern China through routine and nested PCR amplification and characterized together with other genome sequences already deposited in GenBank. The results showed that the TTV1 sequences were highly divergent and could be divided into 1a and 1b subtypes.


Assuntos
DNA Viral/química , DNA Viral/genética , Genoma Viral , Torque teno virus/genética , Animais , China , Genótipo , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Suínos , Torque teno virus/classificação , Torque teno virus/isolamento & purificação
15.
Methods Mol Biol ; 2641: 135-146, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37074647

RESUMO

Gasdermin proteins except DFNB59 are the executioners of pyroptotic cell death. Cleavage of a gasdermin by an active protease causes lytic cell death. Gasdermin C (GSDMC) is cleaved by caspase-8 in response to macrophage-secreted TNF-α. Upon cleavage, the GSDMC-N domain is liberated and oligomerized, followed by pore formation in the plasma membrane. GSDMC cleavage, LDH release, and plasma membrane translocation of GSDMC-N domain are the reliable markers for GSDMC-mediated cancer cell pyroptosis (CCP). Here, we describe the methods for examining GSDMC-mediated CCP.


Assuntos
Neoplasias , Piroptose , Gasderminas , Proteínas de Neoplasias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Morte Celular , Inflamassomos/metabolismo
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123226, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37567026

RESUMO

Ag2O-Ag-PSi (porous silicon) surface-enhanced Raman scattering (SERS) chip was successfully synthesized by electrochemical corrosion, in situ reduction and heat treatment technology. The influence of different heat treatment temperature on SERS performance of the chip is studied. The results show that the chip treated at 300 °C has the best SERS performance. The chip was composed of Ag2O-Ag nano core shell with a diameter of 40-60 nm and porous silicon substrate. Then, the optimized chip was used to perform SERS test on serum samples from 30 healthy volunteers and 30 early breast cancer patients, and the baseline was corrected by LabSpec6 software. Finally, the data were analyzed by principal component analysis combined with t-distributed Stochastic Neighbor Embedding (PCA-t-SNE). The results showed that the accuracy of the improved substrate combined with multivariate statistical method was 98%. The shelf life of the chips exceeded six months due to the presence of the Ag2O shell. This study provides a basis for developing a low-cost rapid and sensitive early screening technology for breast cancer.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Nanopartículas Metálicas , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Silício , Prata , Análise Espectral Raman/métodos
17.
Anal Chim Acta ; 1254: 341116, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37005026

RESUMO

Ag2O-Ag-porous silicon Bragg mirror (PSB) composite SERS substrates were successfully synthesized by using a combination of electrochemical and thermochemical methods. Test results showed that the SERS signal increased and decreased as the annealing temperature used for the substrate increased, where the most intense SERS signal was obtained using a substrate annealed at 300 °C. Stability test results showed substantial enhancement of the SERS signal intensity of the Ag2O-Ag-PSB composite one month after preparation compared with that of conventional Ag-PSB. We conclude that Ag2O nanoshells play an essential role in SERS signal enhancement. Ag2O prevents natural oxidation of Ag nanoparticles (AgNPs) and has a solid localized surface plasmon resonance (LSPR). SERS signal enhancement was tested using this substrate for serum from patients with Sjögren's syndrome (SS) and Diabetic nephropathy (DN), as well as from healthy controls (HC). SERS feature extraction was performed using principal component analysis (PCA). The extracted features were analyzed by a support vector machine (SVM) algorithm. Finally, a rapid screening model for SS and HC, as well as DN and HC, was developed and used to perform controlled experiments. The results showed that the diagnostic accuracy, sensitivity and selectivity for SERS technology combined with machine learning algorithms reached 90.7%, 93.4% and 86.7% for SS/HC and 89.3%, 95.6% and 80% for DN/HC, respectively. The results of this study show that the composite substrate has excellent potential to be developed into a commercially available SERS chip for medical testing.


Assuntos
Nanopartículas Metálicas , Silício , Humanos , Análise Espectral Raman/métodos , Prata , Porosidade
18.
Am J Cancer Res ; 13(4): 1209-1239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168336

RESUMO

Nuclear epidermal growth factor receptor (EGFR) has been shown to be correlated with drug resistance and a poor prognosis in patients with cancer. Previously, we have identified a tripartite nuclear localization signal (NLS) within EGFR. To comprehensively determine the functions and underlying mechanism of nuclear EGFR and its clinical implications, we aimed to explore the nuclear export signal (NES) sequence of EGFR that is responsible for interacting with the exportins. We combined in silico prediction with site-directed mutagenesis approaches and identified a putative NES motif of EGFR, which is located in amino acid residues 736-749. Mutation at leucine 747 (L747) in the EGFR NES led to increased nuclear accumulation of the protein via a less efficient release of the exportin CRM1. Interestingly, L747 with serine (L747S) and with proline (L747P) mutations were found in both tyrosine kinase inhibitor (TKI)-treated and -naïve patients with lung cancer who had acquired or de novo TKI resistance and a poor outcome. Reconstituted expression of the single NES mutant EGFRL747P or EGFRL747S, but not the dual mutant along with the internalization-defective or NLS mutation, in lung cancer cells promoted malignant phenotypes, including cell migration, invasiveness, TKI resistance, and tumor initiation, supporting an oncogenic role of nuclear EGFR. Intriguingly, cells with germline expression of the NES L747 mutant developed into B cell lymphoma. Mechanistically, nuclear EGFR signaling is required for sustaining nuclear activated STAT3, but not for Erk. These findings suggest that EGFR functions are compartmentalized and that nuclear EGFR signaling plays a crucial role in tumor malignant phenotypes, leading to tumorigenesis in human cancer.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 276: 121215, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35395460

RESUMO

The ternary CdS/Ag/TiO2 NTs photocatalysts with indirect Z-scheme heterojunctions were synthesized by the photoreduction deposition of Ag and successive ionic layer adsorption and reaction (SILAR) of CdS on TiO2 nanotube arrays (TiO2 NTs). The elemental composition, microstructure, photoresponse and photoelectrochemical property of the photocatalyst were systematically characterized. The results proved that compared with binary heterojunction, the light absorption range of the ternary CdS/Ag/TiO2 NTs photocatalyst was significantly extended, and the photoelectron transportation efficiency was improved. Under sunlight irradiation, the photocatalytic capacity was verified by investigating the photodegradation of MB and RhB dyes. The CdS/Ag/TiO2 NTs exhibited the optimal photocatalytic performance with the degradation efficiency of 82.24% for RhB and 100% for MB. The synthesized CdS/Ag/TiO2 NTs had high photocatalytic hydrogen evolution capacity and stability, and the hydrogen production reached 806.33 µmol·cm-2. Based on the results of electron spin resonance spectroscopy (ESR) and free radical trapping, the photocatalytic reaction mechanism was explained. The synthesis of ternary CdS/Ag/TiO2 NTs provides a practical reference and guidance for designing high-efficient photocatalysts with Z-scheme heterojunctions toward solar energy development for H2 generation, pollutant remediation and photoelectric conversion.

20.
J Nanosci Nanotechnol ; 11(11): 9818-22, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413301

RESUMO

High-density CuS nanoparticle nanowire (NPNW) arrays were successfully synthesized at room temperature by a simple paired cell method. The as-prepared nanowire arrays were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The results indicate that the nanowire diameter is dependent on the pore size of the used ordered porous anodic alumina (OPAA) template and larger than the corresponding pore diameter of the template due to the corrosion effect of Na2S solution on the template. The nanowire is composed of CuS nanoparticles with hexagonal structure. When the reaction time is long enough, the nanowire is solid and composed of nearly spherical CuS nanoparticles. When the reaction time is short, only middle part of the nanowire is solid and composed of nearly spherical CuS nanoparticles, however, the tops are hollow and mainly composed of flake-like nanoparticles. The formation mechanism of CuS nanoparticle nanowires was proposed to be a heterogeneous nucleation, coalescence, aggregation and filling process.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA