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1.
Carcinogenesis ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819072

RESUMO

Lung cancer is a major contributor to cancer deaths worldwide and is on the rise. Although surgical resection has been widely used as a standard of therapy for lung cancer patients, the relapse rate after surgery is high. It is still unclear whether there is a potential drug that can reduce the probability of post-surgical recurrence in lung cancer patients. We used five typical lung cancer cell lines as well as 41 lung cancer tissue samples and paracancer tissue samples to investigate the expression levels of IRF6 and FUS1. We also treated lung cancer cells (H322 and A549) with different concentrations of sevoflurane to study its influence on lung cancer cell tumorigenesis. Lentivirus-mediated gain-of-function studies of IRF6 and FUS1 were applied to validate the role of IRF6 and FUS1 in lung cancer. Next, we used short hairpin RNA-mediated loss of function of IRF6 and luciferase, ChIP assays to validate the regulatory role of IRF6 on FUS1. Our findings reported that IRF6 was up-regulated in lung cancer tissues, while FUS1 was down-regulated. Functional assays revealed that sevoflurane inhibits lung cancer development by downregulating IRF6 expression. Luciferase assay and ChIP-qPCR assay uncovered that IRF6 represses FUS1 transcriptional expression in lung cancer cells. We have shown that sevoflurane prevents lung cancer development by downregulating IRF6 to stimulate FUS1 transcription; indicating that sevoflurane can be used as the potential anesthetic drug in surgical resection to reduce post-operative tumor relapse in lung cancer patients.

2.
Small ; 14(17): e1703623, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29611622

RESUMO

Indium nitride (InN) is one of the promising narrow band gap semiconductors for utilizing solar energy in photoelectrochemical (PEC) water splitting. However, its widespread application is still hindered by the difficulties in growing high-quality InN samples. Here, high-quality InN nanopyramid arrays are synthesized via epitaxial growth on ZnO single-crystals. The as-prepared InN nanopyramids have well-defined exposed facets of [0001], [11-2-2], [1-212], and [-2112], which provide a possible routine for understanding water oxidation processes on the different facets of nanostructures in nanoscale. First-principles density functional calculations reveal that the nonpolar [11-2-2] face has the highest catalytic activity for water oxidation. PEC investigations demonstrate that the band positions of the InN nanopyramids are strongly altered by the ZnO substrate and a heterogeneous n-n junction is naturally formed at the InN/ZnO interface. The formation of the n-n junction and the built-in electric field is ascribed to the efficient separation of the photogenerated electron-hole pairs and the good PEC performance of the InN/ZnO. The InN/ZnO shows good photostability and the hydrogen evolution is about 0.56 µmol cm-2 h-1 , which is about 30 times higher than that of the ZnO substrate. This study demonstrates the potential application of the InN/ZnO photoanodes for PEC water splitting.

3.
Opt Express ; 25(5): 5091-5100, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28380774

RESUMO

Mg-alloyed ZnO nanocombs were synthesized by the chemical vapor deposition method. The morphology and optoelectronic properties of the nanocombs were systematically investigated. The photodetection capability of the Mg-alloyed ZnO nanocomb was demonstrated by fabrication of a two terminal nanocomb device. It was found that the nanocomb with a high surface-to-volume ratio absorbed the photons effectively in the 310-400 nm range and enabled ultra-high photoconductive gain of 1.9 × 106. From experiments and theoretical analysis, the teeth part of the nanocomb served as a negative gate upon accumulation of electrons by adsorption of oxygen molecules at the teeth, which reduced the dark current of the backbone of the nanocomb and led to an increase in the photoconductive gain of the nanocomb detector.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36875936

RESUMO

Abstract: The interaction of natural and hydraulic fractures may facilitate lateral fluid propagation in an unconventional reservoir resulting in fast fluid pressure transmission from treatment wells to a fault zone and potential fault shear slip reactivation and associated induced seismicity. Several induced earthquakes (up to 4.1 Mw) occurred since 2013 during hydraulic fracturing of the Upper Devonian Duvernay Formation in the Western Canada Sedimentary Basin. The mechanism of lateral fluid migration in the unconventional reservoir is not well understood. The current study aims to investigate the interaction of natural fractures and hydraulic fractures for the case study in the area south of Fox Creek, where a linear zone of induced earthquakes (up to 3.9 Mw) occurred along a fault in 2015 during hydraulic fracturing of horizontal wells. We analyze the growth of hydraulic fractures in presence of natural fractures, the impact of resulting complex fracture network on fluid transmission and fluid pressure buildup around the treatment wells. Hydraulic fracture modeling (HFM), reservoir simulations and 3D coupled reservoir-geomechanical modeling are applied to match the timing of hydraulic fracture propagation and transmitted fluid pressure increase in the fault zone versus induced earthquake occurrence. HFM results are verified by microseismic clouds distribution. Reservoir simulations are validated by a history matching of fluid injection volume and bottomhole pressure data. Additional HFM simulations are carried out to optimize the pumping schedule in the studied well pad that would help to prevent hydraulic fractures reaching the fault and minimize the risk of induced seismicity. Article highlights: Stress anisotropy and simulated natural fractures impact lateral growth of complex hydraulic fractures and reservoir pressure buildup.Predicted fluid pressure transmission to a fault zone results in fault dextral shear slip reactivation matching induced seismicity.Optimized pumping schedule helps to minimize risks of fault reactivation and induced seismicity while preserving overall pad performance.

5.
Nanomaterials (Basel) ; 13(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38133043

RESUMO

The AlTiVCuN coatings were deposited by magnetron sputtering with anode layer ion source (ALIS) assistance, and the microstructure and mechanical properties were significantly affected by the ion source power. With increasing the ion source power from 0 to 1.0 kW, the deposition rate decreased from 2.6 to 2.1 nm/min, and then gradually increased to 4.0 nm/min at 3.0 kW, and the surface roughness gradually decreased from 28.7 nm at 0 kW to 9.0 nm at 3.0 kW. Due to the enhanced ion bombardment effect, the microstructure of the coatings changed from a coarse into a dense columnar structure at 1.0 kW, and the grain size increased at higher ion source powers. All the coatings exhibited c-TiAlVN phase, and the preferred orientation changed from the (220) to the (111) plane at 3.0 kW. Due to the low Cu contents (1.0~3.1 at.%), the Cu atoms existed as an amorphous phase in the coatings. Due to the microstructure densification and high residual stress, the highest hardness of 32.4 GPa was achieved for the coating deposited at 1.0 kW.

6.
Materials (Basel) ; 17(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38204081

RESUMO

To improve the gas ionization ratio, the Mo-V-Cu-N coatings were deposited by pulsed dc magnetron sputtering with assistance from an anode layer ion source, and the influence of the V/Mo atomic ratio was explored with regard to the microstructure and mechanical properties of the coatings. The findings of this study indicated that the MoVCuN coatings exhibited a solid solution phase of FCC B1-MoVN with a prominent (220) preferred orientation, and the deposition rate was found to decrease from 4.7 to 1.8 nm/min when the V/Mo atomic ratio increased. The average surface roughness of the MoVCuN coatings gradually decreased, and the lowest surface roughness of 6.9 nm was achieved at a V/Mo atomic ratio of 0.31. Due to the enhanced ion bombardment effect, the coatings changed from a coarse columnar to a dense columnar crystal structure, and promoted grain refinement at higher V/Mo atomic ratios, contributing to a gradual improvement in the compressive residual stress, hardness and adhesion strength of the coatings.

7.
Plants (Basel) ; 11(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35684273

RESUMO

Extensive stolon development and growth are superior traits for rapid establishment as well as post-stress regeneration in stoloniferous grass species. Despite the importance of those stoloniferous traits, the regulation mechanisms of stolon growth and development are largely unknown. The objectives of this research were to elucidate the effects of the reallocation of soluble sugars for energy reserves and endogenous hormone levels for cell differentiation and regeneration in regulating stolon growth of a perennial turfgrass species, creeping bentgrass (Agrostis stolonifera L.). Plants were grown in growth chambers with two CO2 concentrations: ambient CO2 concentration (400 ± 10 µmol mol-1) and elevated CO2 concentration (800 ± 10 µmol mol-1). Elevated CO2 enhanced stolon growth through increasing stolon internode number and internode length in creeping bentgrass, as manifested by the longer total stolon length and greater shoot biomass. The content of glucose, sucrose, and fructose as well as endogenous IAA were accumulated in stolon nodes and internodes but not in leaves or roots under elevated CO2 concentration. These results illustrated that the production and reallocation of soluble sugars to stolons as well as the increased level of IAA in stolon nodes and internodes could contribute to the enhancement of stolon growth under elevated CO2 in creeping bentgrass.

8.
J Cancer ; 13(14): 3554-3565, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36484011

RESUMO

Colorectal cancer (CRC) is one of the major killer diseases worldwide, and more effective therapeutic compounds for CRC treatment are urgently needed. Although bioactive natural products derived from endophytic fungi have been extensively employed as antibiotics and anticancer agents, little is known about the effect of Rhytidhysteron sp. BZM-9 (an endophytic fungus)-derived compounds on CRC. Herein, a natural molecule porric acid E was isolated from Rhytidhysteron sp. BZM-9. Alamar Blue cell viability assay, Western blotting, transmission electron microscopy, flow cytometry analysis, and fluorescence image examination were employed to evaluate the antitumor effects of porric acid E on CRC cell lines. To establish the xenograft tumor model, nude mice received subcutaneous implants consisting of CRC cells on their flanks. Then the mice were treated with porric acid E or vehicle to assess the tumor-killing effects. The results revealed that porric acid E exhibited cytotoxicity by inhibiting proliferation and promoting apoptosis in CRC cells in vitro. Additionally, compared with fluorouracil (5-FU), porric acid E exhibited a more potent inhibitory effect on CRC HT29 cells. Importantly, extensive autophagy induced by porric acid E was detected in CRC cells, whereas inhibition of autophagy could significantly ameliorate porric acid E-mediated cytotoxic effect on CRC cells. Moreover, porric acid E treatment could markedly suppress subcutaneous HT29 xenograft tumor growth in vivo. Bioinformatics prediction indicated that Beclin-1 might be the potential target of porric acid E. These findings might afford a useful and important method for the treatment of CRC through fungal endophyte-derived natural compounds.

9.
Exp Biol Med (Maywood) ; 246(17): 1869-1883, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34171978

RESUMO

Pancreatic cancer is a highly malignant cancer of the pancreas with a very poor prognosis. Methylation of histone lysine residues is essential for regulating cancer physiology and pathophysiology, mediated by a set of methyltransferases (KMTs) and demethylases (KDMs). This study surveyed the expression of methylation regulators functioning at lysine 9 of histone 3 (H3K9) in pancreatic lesions and explored the underlying mechanisms. We analyzed KDM1A and KDM3A expression in clinical samples by immunohistochemical staining and searching the TCGA PAAD program and GEO datasets. Next, we identified the variation in tumor growth in vitro and in vivo after knockdown of KDM1A or KDM3A and explored the downstream regulators of KDM1A and KDM3A via RNA-seq, and gain- and loss-of-function assays. Eleven H3K9 methylation regulators were highly expressed in pancreatic cancer, and only KDM1A and KDM3A expression positively correlated with the clinicopathological characteristics in pancreatic cancer. High expression of KDM1A or KDM3A positively correlated with pathological grade, lymphatic metastasis, invasion, and clinical stage. Kaplan-Meier analysis indicated that a higher level of KDM1A or KDM3A led to a shorter survival period. Knockdown of KDM1A or KDM3A led to markedly impaired tumor growth in vitro and in vivo. Mechanistically, CCNA2, a cell cycle-associated gene was partially responsible for KDM1A knockdown-mediated effect and CDK6, also a cell cycle-associated gene was partially responsible for KDM3A knockdown-mediated effect on pancreatic cancer cells. Our study demonstrates that KDM1A and KDM3A are highly expressed in pancreatic cancer and are intimately correlated with clinicopathological factors and prognosis. The mechanism of action of KDM1A or KDM3A was both linked to the regulation of cell cycle-associated genes, such as CCNA2 or CDK6, respectively, by an H3K9-dependent pathway.


Assuntos
Ciclo Celular/fisiologia , Histona Desmetilases/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias Pancreáticas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Histonas/metabolismo , Humanos , Regiões Promotoras Genéticas/genética , Regulação para Cima , Neoplasias Pancreáticas
10.
Cell Death Dis ; 12(7): 626, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140464

RESUMO

Acinar cell injury and the inflammatory response are critical bioprocesses of acute pancreatitis (AP). We investigated the role and underlying mechanism of sulfiredoxin-1 (Srxn1) in AP. Mild AP was induced by intraperitoneal injection of cerulein and severe AP was induced by partial duct ligation with cerulein stimulation or intraperitoneal injection of L-arginine in mice. Acinar cells, neutrophils, and macrophages were isolated. The pancreas was analyzed by histology, immunochemistry staining, and TUNEL assays, and the expression of certain proteins and RNAs, cytokine levels, trypsin activity, and reactive oxygen species (ROS) levels were determined. Srxn1 was inhibited by J14 or silenced by siRNA, and overexpression was introduced by a lentiviral vector. Transcriptomic analysis was used to explore the mechanism of Srxn1-mediated effects. We also evaluated the effect of adeno-associated virus (AAV)-mediated overexpression of Srxn1 by intraductal administration and the protection of AP. We found that Srxn1 expression was upregulated in mild AP but decreased in severe AP. Inhibition of Srxn1 increased ROS, histological score, the release of trypsin, and inflammatory responses in mice. Inhibition of Srxn1 expression promoted the production of ROS and induced apoptosis, while overexpression of Srxn1 led to the opposite results in acinar cells. Furthermore, inhibition of Srxn1 expression promoted the inflammatory response by accumulating and activating M1 phenotype macrophages and neutrophils in AP. Mechanistically, ROS-induced ER stress and activation of Cathepsin B, which converts trypsinogen to trypsin, were responsible for the Srxn1 inhibition-mediated effects on AP. Importantly, we demonstrated that AAV-mediated overexpression of Srxn1 attenuated AP in mice. Taken together, these results showed that Srxn1 is a protective target for AP by attenuating acinar injury and inflammation through the ROS/ER stress/Cathepsin B axis.


Assuntos
Catepsina B/metabolismo , Estresse do Retículo Endoplasmático , Terapia Genética , Estresse Oxidativo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Pâncreas/enzimologia , Pancreatite/prevenção & controle , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose , Catepsina B/genética , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Ativação de Neutrófilo , Neutrófilos/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Pâncreas/patologia , Pancreatite/enzimologia , Pancreatite/genética , Pancreatite/patologia , Transdução de Sinais , Regulação para Cima
11.
ACS Appl Mater Interfaces ; 9(22): 18836-18844, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28525707

RESUMO

Epitaxial two-dimensional GaTe nanosheets on ZnO nanowires were routinely prepared via a two-step chemical vapor deposition procedure. The epitaxial relationship and growth mechanism of the GaTe/ZnO core/shell structures were explored and attributed to a layer-overlayer model. The hybrid structures increased the surface area and the favorable p-n heterojunction enhanced the charge separation for photoelectrochemical performance in water splitting. The above synergistic effects boosted the photocurrent density from -0.3 mA cm-2 for the pristine ZnO nanowires to -2.5 mA cm-2 for the core/shell GaTe/ZnO nanowires at -0.39 V vs RHE under the visible light irradiation. This highlights the promise for utilization of GaTe nanosheet/ZnO nanowires as efficient photoelectrocatalyst for water splitting.

12.
Medicine (Baltimore) ; 95(51): e5572, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28002331

RESUMO

RATIONAL: Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasm which expresses both myogenic and melanocytic markers. PEComas are found in a variety locations in the body, but up to now only approximately 30 cases about hepatic perivascular epithelioid cell tumor are reported in English language worldwide. PATIENT CONCERNS: A 32-year-old woman was admitted in our hospital with intermittent right upper quadrant pain for 1 month and recent (1 day) progressive deterioration. DIAGNOSES: Based on the results of the laboratory examinations and the findings of the computed tomography, the diagnosis of hepatic hamartoma or the hepatocecullar carcinoma with hemorrhage was made. INTERVENTIONS: The patient underwent a segmentectomy of the liver, and the finally diagnosis of hepatic PEComa was made with immunohistochemical confirmation with HMB-45 and SMA. OUTCOMES: There is no clinical or radiographic evidence of recurrence 9 months after surgery. LESSONS: This kind of tumor is extremely rare and the natural history of PEComa is uncertain, as the treatment protocol for hepatic PEComa has not reached a consensus. But the main treatment of the disease may be surgical resection. Only after long term follow-up can we know whether the tumor is benign or malignant. It appears that longer clinical follow-up is necessary in all patients with hepatic PEComas.


Assuntos
Neoplasias Hepáticas/diagnóstico , Neoplasias de Células Epitelioides Perivasculares/diagnóstico , Adulto , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias de Células Epitelioides Perivasculares/diagnóstico por imagem , Neoplasias de Células Epitelioides Perivasculares/patologia , Neoplasias de Células Epitelioides Perivasculares/cirurgia , Tomografia Computadorizada por Raios X
13.
Nanoscale ; 7(7): 2889-93, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25620621

RESUMO

We report an excitation of surface plasmons in silver nanowires (AgNWs) which were embedded in flexible polymer nanofibers. Using waveguiding excitation, surface plasmons in AgNWs were excited and propagated. By directing light of 650, 532, and 473 nm wavelengths into the nanofiber, surface plasmons in an embedded single AgNW (average diameter 400 nm, length 4.3 µm) were excited and the corresponding propagation lengths for the three wavelengths are 10.6, 7.7, and 5.1 µm. It was also found that, when a spatially incoherent white light of a halogen lamp with an excitation optical power of 80 µW was coupled into the polymer nanofiber, a surface plasmon mediated interference fringe was observed. In addition, on the basis of surface plasmon excitation, two adjacent AgNWs embedded in the polymer nanofibers were demonstrated to serve as coupled plasmonic waveguides.

14.
Sci Rep ; 5: 13199, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26289498

RESUMO

Nanostructured terahertz detectors employing a single semiconducting nanowire or graphene sheet have recently generated considerable interest as an alternative to existing THz technologies, for their merit on the ease of fabrication and above-room-temperature operation. However, the lack of alignment in nanostructure device hindered their potential toward practical applications. The present work reports ordered terahertz detectors arrays based on neatly aligned InN nanowires. The InN nanostructures (nanowires and nano-necklaces) were achieved by chemical vapor deposition growth, and then InN nanowires were successfully transferred and aligned into micrometer-sized groups by a "transfer-printing" method. Field effect transistors on aligned nanowires were fabricated and tested for terahertz detection purpose. The detector showed good photoresponse as well as low noise level. Besides, dense arrays of such detectors were also fabricated, which rendered a peak responsivity of 1.1 V/W from 7 detectors connected in series.

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