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1.
J Cell Physiol ; 234(7): 11265-11275, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30499104

RESUMO

Non-small-cell lung cancer (NSCLC) accounts for the majority of the lung cancer cases that have become a leading cause of cancer deaths worldwide. Overexpression of transcription factor forkhead box M1 (FOXM1) is involved in the inauspicious development of several types of cancer, including lung tumor aggressiveness. Our laboratory has previously found that MED28, a Mediator subunit for transcriptional activation, modulates cell growth, epithelial-mesenchymal transition, migration, and invasion in human breast cancer cells. The objective of the current study is to investigate the potential role of MED28 and FOXM1 in NSCLC. In addition to A549 and PC9 cells, we also used a doxycycline-inducible system to generate FOXM1-overexpressed A549-DN cells, and we explored the connection of MED28 with FOXM1 and their effect on migration. Herein, we report that the increased expression levels of both MED28 and FOXM1 elevated the expression of matrix metalloproteinase 2 (MMP2), a metastasis marker, which enhanced cell migration and matrigel invasion of NSCLC cells. Furthermore, MED28 interacted with FOXM1, and both exhibited a mutual effect on the expression and subcellular localization. Moreover, MED28 small interfering RNA-mediated MMP2 gene suppression could be attenuated by inducible expression of a constitutively active form of FOXM1, which consequently restored the migration and invasion ability of NSCLC cells. Our data indicate that MED28 interacts with FOXM1, and each affects the expression and localization of the other, and, more importantly, both regulate MMP2-dependent migration and invasion in human lung cancer cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Proteína Forkhead Box M1/metabolismo , Neoplasias Pulmonares/patologia , Metaloproteinase 2 da Matriz/metabolismo , Complexo Mediador/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Proteína Forkhead Box M1/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Complexo Mediador/genética , Invasividade Neoplásica/genética , Interferência de RNA , RNA Interferente Pequeno/genética
2.
Phys Chem Chem Phys ; 18(22): 15363-8, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27212639

RESUMO

Ethanol-based nanofluids have attracted much attention due to the enhancement in heat transfer and their potential applications in nanofluid-type fuels and thermal storage. Most research has been conducted on ethanol-based nanofluids containing various nanoparticles in low mass fraction; however, to-date such studies based on high weight fraction of nanoparticles are limited due to the poor stability problem. In addition, very little existing work has considered the inevitable water content in ethanol for the change of thermal conductivity. In this paper, the highly stable and well-dispersed TiO2-ethanol nanofluids of high weight fraction of up to 3 wt% can be fabricated by stirred bead milling, which enables the studies of thermal conductivity of TiO2-ethanol nanofluids over a wide range of operating temperatures. Our results provide evidence that the enhanced thermal conductivity is mainly contributed by the percolation network of nanoparticles at low temperatures, while it is in combination with both Brownian motion and local percolation of nanoparticle clustering at high temperatures.

3.
Nanotechnology ; 24(5): 055401, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23324138

RESUMO

Enhanced photoelectrochemical (PEC) performances of Ga(2)O(3) and GaN nanowires (NWs) grown in situ from GaN were demonstrated. The PEC conversion efficiencies of Ga(2)O(3) and GaN NWs have been shown to be 0.906% and 1.09% respectively, in contrast to their 0.581% GaN thin film counterpart under similar experimental conditions. A low crystallinity buffer layer between the grown NWs and the substrate was found to be detrimental to the PEC performance, but the layer can be avoided at suitable growth conditions. A band bending at the surface of the GaN NWs generates an electric field that drives the photogenerated electrons and holes away from each other, preventing recombination, and was found to be responsible for the enhanced PEC performance. The enhanced PEC efficiency of the Ga(2)O(3) NWs is aided by the optical absorption through a defect band centered 3.3 eV above the valence band of Ga(2)O(3). These findings are believed to have opened up possibilities for enabling visible absorption, either by tailoring ion doping into wide bandgap Ga(2)O(3) NWs, or by incorporation of indium to form InGaN NWs.

4.
Nanotechnology ; 22(12): 125701, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21317486

RESUMO

An on-chip approach for fabricating ferromagnetic/semiconductor-nanotip heterojunctions is demonstrated. The high-density array of Si nanotips (SiNTs) is employed as a template for depositing La(0.7)Sr(0.3)MnO(3) (LSMO) rods with a pulsed-laser deposition method. Compared with the planar LSMO/Si thin film, the heterojunction shows a large enhancement of room temperature magnetoresistance (MR) ratio up to 20% under 0.5 T and a bias current of 20 µA. The MR ratio is found to be tunable, which increases with increasing external bias and the aspect ratios of the nanotips. Electric-field-induced metallization, in conjunction with nanotip geometry, is proposed to be the origin for the giant MR ratio.

5.
Oncogene ; 40(30): 4847-4858, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34155349

RESUMO

Small cell lung cancer (SCLC) continues to cause poor clinical outcomes due to limited advances in sustained treatments for rapid cancer cell proliferation and progression. The transcriptional factor Forkhead Box M1 (FOXM1) regulates cell proliferation, tumor initiation, and progression in multiple cancer types. However, its biological function and clinical significance in SCLC remain unestablished. Analysis of the Cancer Cell Line Encyclopedia and SCLC datasets in the present study disclosed significant upregulation of FOXM1 mRNA in SCLC cell lines and tissues. Gene set enrichment analysis (GSEA) revealed that FOXM1 is positively correlated with pathways regulating cell proliferation and DNA damage repair, as evident from sensitization of FOXM1-depleted SCLC cells to chemotherapy. Furthermore, Foxm1 knockout inhibited SCLC formation in the Rb1fl/flTrp53fl/flMycLSL/LSL (RPM) mouse model associated with increased levels of neuroendocrine markers, Ascl1 and Cgrp, and decrease in Yap1. Consistently, FOXM1 depletion in NCI-H1688 SCLC cells reduced migration and enhanced apoptosis and sensitivity to cisplatin and etoposide. SCLC with high FOXM1 expression (N = 30, 57.7%) was significantly correlated with advanced clinical stage, extrathoracic metastases, and decrease in overall survival (OS), compared with the low-FOXM1 group (7.90 vs. 12.46 months). Moreover, the high-FOXM1 group showed shorter progression-free survival after standard chemotherapy, compared with the low-FOXM1 group (3.90 vs. 8.69 months). Our collective findings support the utility of FOXM1 as a prognostic biomarker and potential molecular target for SCLC.


Assuntos
Biomarcadores Tumorais , Proteína Forkhead Box M1/genética , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/mortalidade , Carcinoma de Pequenas Células do Pulmão/etiologia , Carcinoma de Pequenas Células do Pulmão/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Feminino , Proteína Forkhead Box M1/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Carcinoma de Pequenas Células do Pulmão/diagnóstico , Microtomografia por Raio-X , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Sci Rep ; 8(1): 13711, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30209333

RESUMO

With the remote beating of two mutually incoherent laser carriers, the local-oscillator-free long-reach millimeter-wave over fiber (MMWoF) link at 60-GHz band is demonstrated. The unique schemes of the proposed MMWoF are the wavelength-locked colorless laser diode (CLD) modulator, the mutually incoherent optical carrier for heterodyne MMW generation, and the square-law power envelope detection at receiving end. By directly encoding the single-mode with the CLD modulator, the single-carrier modulated QAM-OFDM data is achieved to release the RF power fading after fiber transmission. The mutually incoherent laser beating enables the optical heterodyne MMW generation with two independent optical carriers, which provides the advantages of local-oscillator-free operation and rules out the requirement of dual-mode optical carrier delivery from central office. At the wireless receiving end, the received QAM-OFDM data is self-down-converted to the baseband by employing the square-law power envelope detection. This eliminates the requirement of local oscillator and rules out the influence of the MMW carrier frequency fluctuation between two mutually incoherent lasers (used at central office and remote node), which effectively provides the MMW carrier immunity against the down-conversion instability caused by clock jitter or carrier incoherence. This architecture ensures the transmission of 16.5-Gbit/s 32-QAM OFDM data over 50 km in SMF and 3 m in free-space with the FEC certificated error vector magnitude of 12%, signal-to-noise ratio (SNR) of 18.4 dB, and bit error rate of 3.8 × 10-3. For multi-channel DWDM-PON applications, the proposed local-oscillator-free MMWoF link can successfully perform 11 DWDM channels of 32-QAM OFDM data access at 16.5 Gbit/s per channel via the wavelength controlling of the CLD modulation stage and the detuning of the beating carrier at remote node.

7.
Nat Nanotechnol ; 11(12): 1087-1092, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27749832

RESUMO

Phototaxis is commonly observed in motile photosynthetic microorganisms. For example, green algae are capable of swimming towards a light source (positive phototaxis) to receive more energy for photosynthesis, or away from a light source (negative phototaxis) to avoid radiation damage or to hide from predators. Recently, with the aim of applying nanoscale machinery to biomedical applications, various inorganic nanomotors based on different propulsion mechanisms have been demonstrated. The only method to control the direction of motion of these self-propelled micro/nanomotors is to incorporate a ferromagnetic material into their structure and use an external magnetic field for steering. Here, we show an artificial microswimmer that can sense and orient to the illumination direction of an external light source. Our microswimmer is a Janus nanotree containing a nanostructured photocathode and photoanode at opposite ends that release cations and anions, respectively, propelling the microswimmer by self-electrophoresis. Using chemical modifications, we can control the zeta potential of the photoanode and program the microswimmer to exhibit either positive or negative phototaxis. Finally, we show that a school of microswimmers mimics the collective phototactic behaviour of green algae in solution.


Assuntos
Nanofios/química , Fototaxia/fisiologia , Luz , Locomoção , Microscopia Eletrônica de Varredura , Fotoquímica/instrumentação , Fotoquímica/métodos , Propriedades de Superfície , Titânio/química
9.
Nanoscale ; 6(24): 15309-15, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25384522

RESUMO

By virtue of its amorphous structure with a short-range order feature, the inorganic nanoporous nickel oxyhydroxide (NiOOH) can reversibly and rapidly switch wettability by alternate treatments of environmental chamber (superhydrophobic) and UV/ozone (superhydrophilic). The switchable mechanism of the NiOOH/Ni(OH)2 pair arising from its exceptional intrinsic short-range order-disorder transition together with chemical composition change is highlighted for the first time, which significantly differs from the current stimuli-responsive materials. This distinct multifunctional thin film not only possesses reversible wettability but also is optically patternable/repairable and electrically conductive, which could be applicable in the manufacturing of various micro- and nanostructures. We demonstrate this potential in the rewritable two-dimensional (2D) microfluidic channels and wetting-contrast enhanced selective electroplating.

10.
Chem Commun (Camb) ; 47(33): 9414-6, 2011 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-21773606

RESUMO

A simple and convenient one-pot synthetic route to directly prepare a self-reductive mesoporous copper-iron-silicate (CuO(x)-Fe-silicate)-based catalyst has been developed. The resultant catalyst is highly active and stable in methanol reforming without needing a pre-reduction procedure.

11.
Chem Commun (Camb) ; 47(5): 1473-5, 2011 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-21085741

RESUMO

The unique nanoarchitecture developed in this study and the use of replaceable stainless steel grids as catalyst supports certainly provide a promising platform technique for catalytic generation of high methanol conversion, hydrogen production rate and durability to produce electrical energy.

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