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1.
Artigo em Inglês | MEDLINE | ID: mdl-32079392

RESUMO

Hybrid organic-inorganic perovskite solar cells (PSCs) have attracted extensive research interests as the most rapidly developing next-generation thin-film photovoltaic technology, yet their efficiency, scalability, and durability remain challenging. Although α-Fe2O3 served as electron transporting layer (ETL) of planar PSCs and exhibited a much higher humidity and UV light-stability compared to TiO2, the photovoltaic conversion efficiency (PCE) of Fe2O3-based planar PSCs was still below 15% because of poor interface contact between α-Fe2O3 and perovskite, and poor crystal quality of perovskite. In this work, we have engineered the interfaces throughout the entire solar cell via incorporating N, S co-doped graphene quantum dots (NSGQDs). The NSGQDs played remarkably multifunctional roles: i) facilitated the perovskite crystal growth; ii) eased charge extraction at both anode and cathode interfaces; iii) induced the defect passivation and suppressed the charge recombination. When assembled with a α-Fe2O3 ETL, the planar PSCs exhibited a significant efficiency enhancement from 14% to 19.2%, with an obviously decreased and negligible hysteresis, which created a new record of PCE for Fe2O3-based PSCs to date. In addition, PSCs with the entire device interfacial engineering showed an obviously improved durability, including prominent humidity, UV light and thermal-stabilities. Our interfacial engineering methodology via graphene quantum dots represents a versatile and effective way for building high efficiency and durability solar cells.

2.
Adv Mater ; 32(6): e1905661, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31851401

RESUMO

Defects, inevitably produced within bulk and at perovskite-transport layer interfaces (PTLIs), are detrimental to power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs). It is demonstrated that a crosslinkable organic small molecule thioctic acid (TA), which can simultaneously be chemically anchored to the surface of TiO2 and methylammonium lead iodide (MAPbI3 ) through coordination effects and then in situ crosslinked to form a robust continuous polymer (Poly(TA)) network after thermal treatment, can be introduced into PSCs as a new bifacial passivation agent for greatly passivating the defects. It is also discovered that Poly(TA) can additionally enhance the charge extraction efficiency and the water-resisting and light-resisting abilities of perovskite film. These newly discovered features of Poly(TA) make PSCs herein achieve among the best PCE of 20.4% ever reported for MAPbI3 with negligible hysteresis, along with much enhanced ultraviolet, air, and operational stabilities. Density functional theory calculations reveal that the passivation of MAPbI3 bulk and PTLIs by Poly(TA) occurs through the interaction of functional groups (COOH, CS) in Poly(TA) with under-coordinated Pb2+ in MAPbI3 and Ti4+ in TiO2 , which is supported by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy.

3.
Onco Targets Ther ; 12: 7451-7457, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686850

RESUMO

Purpose: Circular RNAs (circRNAs) are emerging as promising biomarkers for various human malignancies. However, the application of circRNAs as non-invasive biomarkers in high-grade serous ovarian cancer (SOC) remains to be elucidated. Here, we aim to investigate the feasibility of using serum circSETDB1, a tumor-promoting circRNA generated from the SET domain bifurcated histone lysine methyltransferase 1 (SETDB1), known to be upregulated in SOC,as a biomarker for detecting SOC progression, predicting relapse, and evaluating the effectiveness of SOC treatment. Methods: Serum circSETDB1 levels were measured using quantitative real-time RCR in 60 SOC patients (18 primary chemoresistance, 42 primary chemosensitive) and 60 healthy volunteers. Progression-free survival curve was calculated by Kaplan-Meier analysis. Diagnostic value was analyzed using receiver operating characteristic curve (ROC) method. Results: Serum circSETDB1 expression is upregulated in SOC patients. Higher levels of circSETDB1 are positively associated with advanced clinical stage, lymph node metastasis of SOC patients. Notably, serum circSETDB1 levels are significantly increased in primary chemoresistance patients. Patients with higher levels of circSETDB1 have a shorter progression-free survival time. In addition, diagnostic value analyses revealed that serum circSETDB1 can distinguish patients with SOC from healthy volunteers as well as patients with primary chemoresistance from those with primary chemosensitivity. Conclusion: Our data suggest that serum circSETDB1 may serve as a novel non-invasive biomarker for detecting SOC progression and predicting response to chemotherapy and relapse in high-grade serous ovarian cancer.

4.
Small ; 15(47): e1904372, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31609079

RESUMO

Minimization of defects and ion migration in organic-inorganic lead halide perovskite films is desirable for obtaining photovoltaic devices with high power conversion efficiency (PCE) and long-term stability. However, achieving this target is still a challenge due to the lack of efficient multifunctional passivators. Herein, to address this issue, n-type goethite (FeOOH) quantum dots (QDs) are introduced into the perovskite light-absorption layer for achieving efficient and stable perovskite solar cells (PSCs). It is found that the iron, oxygen, and hydroxyl of FeOOH QDs can interact with iodine, lead, and methylamine, respectively. As a result, the crystallization kinetics process can be retarded, thereby resulting in high quality perovskite films with large grain size. Meanwhile, the trap states of perovskite can be effectively passivated via interaction with the under-coordinated metal (Pb) cations, halide (I) anions on the perovskite crystal surface. Consequently, the PSCs with FeOOH QDs achieve a high efficiency close to 20% with negligible hysteresis. Most strikingly, the long-term stability of PSCs is significantly enhanced. Furthermore, compared with the CH3 NH3 PbI3 -based device, a higher PCE of 21.0% is achieved for the device assembled with a Cs0.05 FA0.81 MA0.14 PbBr0.45 I2.55 perovskite layer.

5.
J Mol Graph Model ; 93: 107439, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31479950

RESUMO

Multipoint hydrogen bonded motifs with intermolecular N-H⋯N hydrogen bonds have been theoretically studied at the PBE0-D3/ma-def2-TZVP level. The properties of electron density at the bond critical points of hydrogen bonds have been analyzed through "atoms in molecule" (AIM) theory and "electron localization function" (ELF) method. The results imply that the secondary electrostatic interactions have a significant effect to the strength of multipoint hydrogen bonds. Good relationships are found between ρ, ELF parameters and CVB indices. Moreover, they also show good relationships with hydrogen bond distances. These parameters may be treated as universal indicators of the hydrogen bond strength. The investigations would be useful in understanding comprehensively the multipoint hydrogen bonded motifs and helpful in designing the supramolecular systems through multipoint hydrogen bonds.

6.
J Colloid Interface Sci ; 556: 466-475, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473537

RESUMO

In this work, we have synthesized Cu-doped MnO2@diatomite successfully though a one-step hydrothermal approach. Meanwhile, application for degradation of methylene blue in Fenton-like system was investigated. The compounds were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS), Inductively Coupled Plasma analysis (ICP) and UV-vis spectroscopy measurements, beam scanning electron microscope (FIB/SEM), energy dispersive X-ray spectrometer (EDS). The observations revealed that copper was indeed intercalated into layered structure of MnO2 and Density functional theory (DFT) calculations predicted that Cu2+ intercalated MnO2@diatomite brought about the narrowing of band gap and the enhancing of charge mobility during catalysis. Electron Density Difference of CuMnD demonstrated excellent oxidation ability to dissociate H2O2 and generate hydroxyl radical (OH) to degrade the MB. Moreover, the proper copper doping of sample is more easily to form oxygen defect, which generate more surface hydroxyl groups as reaction sites for surface adsorption. In addition, the degradation efficiency of CuMnD was tremendously influenced by the initial pH, H2O2 dosage and copper content of catalyst. Ultimately, 0.02-25-CuMnD along with molar ration of Cu/Mn with 0.4402 showed the best degradation efficiency which was about 96.2% within 4 h with 16.5 mM of H2O2 and pH 2.06.

7.
Nanoscale ; 11(41): 18968-18994, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31361294

RESUMO

Hydrogen production from photoelectrochemical (PEC) water splitting using semiconductor photocatalysts has attracted great attention to realize clean and renewable energy from solar energy. The visible light response of WO3 with a long hole diffusion length (∼150 nm) and good electron mobility (∼12 cm2 V-1 s-1) makes it suitable as the photoanode. However, WO3 suffers from issues including rapid recombination of photoexcited electron-hole pairs, photo-corrosion during the photocatalytic process due to the formation of peroxo-species, sluggish kinetics of photogenerated holes, and slow charge transfer at the semiconductor/electrolyte interface. This work highlights the approaches to overcome these drawbacks of WO3 photoanodes, including: (i) the manipulation of nanostructured WO3 photoanodes to decrease the nanoparticle size to promote hole migration to the WO3/electrolyte interface which benefits the charge separation; (ii) doping or introducing oxygen vacancies to improve electrical conductivity; exposing high energy crystal surfaces to promote the consumption of photogenerated holes on the high-active crystal face, thereby suppressing the recombination of photogenerated electrons and holes; (iii) decorating with co-catalysts to reduce the overpotential which inhibits the formation of peroxo-species; (iv) other methods such as coupling with narrow band semiconductors to accelerate the charge separation and controlling the crystal phase via annealing to reduce defects. These approaches are reviewed with detailed examples.

8.
J Colloid Interface Sci ; 544: 155-163, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30836257

RESUMO

Natural diatomite with abundant pores was used as a biotemplate for the massive production of three-dimensional (3D) porous graphene by chemical vapor deposition method. Subsequent template removal and nitrogen doping treatment yield nitrogen doped 3D graphene with preserved shape and complex internal features of the diatomite. After further deposition with MnO2 nanosheets, the N-doped 3D graphene@MnO2 (N-G@MnO2) hybrid exhibited excellent supercapacitor and good oxygen reduction reaction (ORR) performance. Accordingly, the porous N-G@MnO2 electrode exhibited a high specific capacitance (411.5 F g-1) and a good cycling performance (88.3% capacitance retention after 4000 charge/discharge cycling test). When tested in a two-electrode configuration, N-G@MnO2 achieved a wide potential window up to 1.8 V with a high energy density of 46.1 Wh kg-1. Furthermore, the as-prepared N-G@MnO2 showed good performance in oxygen reduction reaction, which is comparable to those of commercially available Pt/C electrode. The enhanced capacitive and electrocatalytic properties and stability is due to the synergistic interactions between the porous 3D graphene and MnO2 nanosheets. The results indicate that the 3D N-G@MnO2 could be useful for supercapacitor and ORR catalyst.

9.
Chem Commun (Camb) ; 55(15): 2234-2237, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30714065

RESUMO

Na2TiSiO5 is investigated as a novel anode of the lithium ion battery for the first time. The low working potential (above 0.1 V) and high capacity (>300 mA h g-1) give this material a high energy density, along with improved safety. After 100 cycles, the capacity retention remains at 94%. Furthermore, possible Li+-occupied sites and the migration path in the Na2TiSiO5 structure are also calculated and discussed in this work.

10.
ACS Appl Mater Interfaces ; 10(49): 42436-42443, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30457323

RESUMO

The quality of perovskite films is a crucial factor governing the photovoltaic performance of perovskite solar cells. However, perovskite films fabricated by the conventional one-step spin-coating procedure are far from ideal due to uncontrollable crystal growth. Herein, we report a facile recrystallization procedure using a thiazole additive coupled with vapor annealing to simultaneously modulate the perovskite crystal growth and suppress the surface defects. High quality perovskite films with no pin holes, high crystallinity, large grain size, and low roughness were obtained. Moreover, using the space charge limited current method, we observe that the defect density of the as-prepared perovskite films with the thiazole additive was decreased by 40% when compared with the film without thiazole. The lower defect density of these perovskite films enables the achievement of a final power conversion efficiency of 18% and an exceptionally high fill factor of 0.82, which correspond to a 25% enhancement compared with the control device. Our results reveal a novel and facile path to modulate the perovskite crystal growth and simultaneously suppress the film defect density and increasing efficiency in perovskite photovoltaics and related optoelectronic applications.

11.
J Environ Sci (China) ; 66: 358-367, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29628105

RESUMO

Niobium oxide nanowire-deposited carbon fiber (CF) samples were prepared using a hydrothermal method with amorphous Nb2O5·nH2O as precursor. The physical properties of the samples were characterized by means of numerous techniques, including X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), UV-visible spectroscopy (UV-vis), N2 adsorption-desorption, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy. The efficiency for the removal of Cr(VI) was determined. Parameters such as pH value and initial Cr(VI) concentration could influence the Cr(VI) removal efficiency or adsorption capacity of the Nb2O5/carbon fiber sample obtained after hydrothermal treatment at 160°C for 14hr. The maximal Cr(VI) adsorption capacity of the Nb2O5 nanowire/CF sample was 115mg/g. This Nb2O5/CF sample also showed excellent photocatalytic activity and stability for the reduction of Cr(VI) under UV-light irradiation: the Cr(VI) removal efficiency reached 99.9% after UV-light irradiation for 1hr and there was no significant decrease in photocatalytic performance after the use of the sample for 10 repeated cycles. Such excellent Cr(VI) adsorption capacity and photocatalytic performance was related to its high surface area, abundant surface hydroxyl groups, and good UV-light absorption ability.


Assuntos
Carbono/química , Cromo/química , Nanofios/química , Nióbio/química , Óxidos/química , Adsorção , Fibra de Carbono , Modelos Químicos , Processos Fotoquímicos , Poluentes Químicos da Água
12.
J Nanosci Nanotechnol ; 18(6): 4236-4242, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442768

RESUMO

In this study, rhenium-tungsten mixed particles with different content of rhenium have been prepared by spray-drying method followed by hydrogen reduction. Using such particles, the cathodes have been prepared by powder metallurgy followed by impregnating BaO, CaO, and Al2O3 with 4:1:1 molar ratio. After proper activation, electron emission test is performed in standard parallel-plate diode configuration. The emission results reveal that the Re-W matrix cathode containing 75% rhenium has the highest direct current emission density of 11.67 A/cm2 at 1000 °C. The work function of Re-W matrices has been investigated by density functional theory method in the frame of the generalized gradient approximation (GGA). The theoretical calculation results indicate that the work function of the matrix has limited contribution to the emission current density of Re-W matrix dispenser cathode. The in situ AES, SEM, and XRD were applied and the results reveal that the superior emission property of the 75Re cathode is owing to a plenty of nanoparticles and higher free barium concentration on the cathode surface, which is attributed to the Re3W single phase in 75Re matrix.

13.
Environ Sci Pollut Res Int ; 25(7): 6352-6363, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29247420

RESUMO

Our previous study found that a salt marsh in eastern China can act as a large CH3Cl sink. One striking finding of this previous study was a strong relationship between high-ambient CH3Cl concentrations and fluxes during the growing season. Moreover, the high-ambient CH3Cl concentration was likely to be related to local biomass burning. However, implementation of biomass burning prohibition policies has effectively reduced biomass burning. Therefore, we predicted that the prohibition of biomass burning would alter CH3Cl concentration and flux within the eastern Chinese coastal salt marsh. In this study, we used static flux chambers to measure CH3Cl fluxes in the early (July of 2004 and January of 2005) and middle-late stages (August and December of 2013) of biomass burning prohibition of along a creek and vegetation transects of the salt marsh. After implementation of the biomass burning prohibition, the concentration and flux of CH3Cl directly related to biomass burning changed remarkably. During the middle-late stage of prohibition, the initial CH3Cl concentration was significantly reduced compared to during the early stage of prohibition. Reductions in atmospheric CH3Cl concentration were especially apparent during the growing season, when biomass burning was prohibited and atmospheric CH3Cl concentration dropped to levels nearly as low as the Northern Hemisphere background concentration. Atmospheric CH3Cl concentration significantly varied throughout the salt marsh, with the highest concentrations appearing over the inland areas and mudflat and lower values occurring over the middle locations. This spatial distribution of CH3Cl may have been directly related to the existence and distribution of potential CH3Cl sources, such as coastal seawater, terrestrial biomass burning, and senescent and decaying aboveground biomass. These changes in initial CH3Cl concentration caused by the biomass burning prohibition may eventually lead to shift in the salt marsh from the tendency to act as a CH3Cl sink to the tendency to act as a CH3Cl source. When the initial atmospheric CH3Cl concentration was high, the vegetation stands acted as CH3Cl sinks. Conversely, they became CH3Cl sources. Therefore, we conclude that the biomass burning prohibition altered the ecosystem-atmosphere exchange of CH3Cl within the studied eastern Chinese coastal salt marsh.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Monitoramento Ambiental/métodos , Política Ambiental/tendências , Cloreto de Metila/análise , Áreas Alagadas , Atmosfera/química , Biomassa , China , Estações do Ano , Água do Mar/química
14.
Oncotarget ; 8(41): 69924-69933, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-29050252

RESUMO

NSC67657 is a new steroid drug that induces monocytic differentiation of acute myeloid leukemia cells. Here, we demonstrate that NSC67657 has opposing effects on expression of downstream targets of inhibitor of ß-catenin and TCF (ICAT) and Wnt signaling in HL60 cells. ICAT binds to ß-catenin, and this interaction is further increased in NSC67657-differentiated cells. ICAT overexpression decreases expression of Wnt downstream targets and increases sensitivity of HL60 cells to NSC67657, while ICAT silencing increases Wnt signaling and delays the NSC67657-induced cell differentiation. In addition, pharmacological inhibition of Wnt/ß-catenin signaling increases the NSC67657-induced cell differentiation, while activation of Wnt/ß-catenin signaling inhibits the differentiation, indicating Wnt/ß-catenin signaling inhibits NSC67657-induced monocytic differentiation of HL60 cells. Our data demonstrate the opposing roles of ICAT and Wnt signaling in the NSC67657-induced monocytic differentiation, and suggest that ICAT and Wnt signaling may serve as therapeutic targets for leukemia chemotherapy.

15.
Chem Asian J ; 12(13): 1421-1434, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28556595

RESUMO

Graphitic carbon nitride (g-C3 N4 )-based photocatalysts are promising for photocatalytic water splitting to produce clean solar fuels due to their low cost, suitable band structure and excellent photocatalytic performance. This review focuses on the state-of-the-art progress of the strategies for modifying g-C3 N4 -based photocatalysts toward efficient photocatalytic water splitting. In particular, we highlight the importance of interfacial engineering and nanostructural control to facilitating charge separation and migration. Other strategies including doping and defect engineering are also concisely discussed. Finally, the perspectives on the challenges and future development of g-C3 N4 -based photocatalysts are presented.

16.
Oncotarget ; 8(22): 35890-35901, 2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28415788

RESUMO

Bone morphogenetic protein 9 (BMP9) possesses multiple functions, but its effects on breast cancer cells in adipose microenvironment are still unclear. This study aimed to investigate whether BMP9 is able to modulate the interaction between pre-adipocytes/adipocytes and breast cancer cells. An in vitro co-culture system was established by using pre-adipocytes/adipocytes and MDA-MB-231 breast cancer cells with BMP9 over-expression. The leptin expression and leptin-induced signaling pathway were evaluated in this co-culture system. MTT assay, EdU assay and flow cytometry were used to assess the proliferation of MDA-MB-231 cells. Wound-healing assay and Transwell migration assay were used to assess the migration of MDA-MB-231 cells. Immunofluorescence staining was used to detect the expression of leptin recepter (ObR) in MDA-MB-231 cells. The expression of key molecules in leptin signaling pathway in co-culture system were detected by Western blotting. MDA-MB-231 cells and pre-adipocytes/adipocytes were inoculated into nude mice, the tumor volume was measured, and the protein expression of key molecules in leptin signaling pathway was detected. Results showed BMP9 inhibited breast tumor growth in vitro and in vivo and reduced the migration of breast cancer cells in vitro. MDA-MB-231 cells with BMP9 over-expression decreased leptin expression in pre-adipocytes/adipocytes and had reduced phosphorylation of STAT3, ERK1/2 and AKT. Taken together, our study indicates that BMP9 can inhibit the growth and metastasis of breast cancer cells, which may be related to interaction between pre-adipocytes/adipocytes and MDA-MB-231 cells via leptin signaling pathway.


Assuntos
Adipócitos/metabolismo , Neoplasias da Mama/metabolismo , Comunicação Celular , Fator 2 de Diferenciação de Crescimento/metabolismo , Células 3T3-L1 , Animais , Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Técnicas de Cocultura , Modelos Animais de Doenças , Feminino , Expressão Gênica , Fator 2 de Diferenciação de Crescimento/genética , Xenoenxertos , Humanos , Leptina/metabolismo , Camundongos , Metástase Neoplásica , Transdução de Sinais
17.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 32(11): 1499-1502, 2016 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-27774943

RESUMO

Objective To investigate the effect of overexpressed inhibitor of ß-catenin and T cell factor (ICAT) on the proliferation and migration of human cervical cancer Caski cells. Methods Caski cells were transfected with ICAT recombinant adenovirus (AdICAT). The levels of ICAT mRNA and protein were detected by quantitative real-time PCR (qRT-PCR) and Western blotting, respectively. Effect of ICAT overexpression on proliferation, cell cycle and migration in Caski cells was respectively evaluated by MTT assay, flow cytometry and TranswellTM migration assays. Results The expression of ICAT remarkably increased in Caski cells after AdICAT infection. Overexpression of ICAT promoted Caski cells' proliferation, arrested the cell cycle in the S phase and enhanced cell migration. Conclusion Overexpression of ICAT can promote the proliferation and migration of Caski cervical cancer cells.


Assuntos
Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias do Colo do Útero/metabolismo , Western Blotting , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Citometria de Fluxo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Colo do Útero/patologia , beta Catenina/genética , beta Catenina/metabolismo
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 24(2): 341-6, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-27150989

RESUMO

OBJECTIVE: To investigate the effect of inhibiting and activating Wnt signalling pathway on monocyte differentiation of HL-60 cells induced with a new steroidal drug NSC67657 and its possible mechamism. METHODS: The HL-60 cells were treated with 5, 10 and 20 µmol/L XAV-939 (inhibitor of Wnt signalling pathway) for 3 days, and with 10, 20 and 30 mmol/L LiCl (activator of Wnt signalling pathway) for 1 day; the expression levels of down-stream genes and proteins of Wnt signolling pathway were detected by RT-PCR and Western blot, respectively; the expression of cell surface differentiation antigen CD14 and early apoptosis of HL-60 cells was detected by flow cytometry, moreover the most suitable concentration of Wnt inhibitor and activator for HL-60 cells was determined. Then the HL-60 cells with inhibited and activated Wnt pathway were treated with NSC67657 of 10 µmol/L for 3 days; the expression levels of CD14 and down-stream target proteins of Wnt signalling pathway in blank control (culture mediam) group, simple NSC67657-treated group, NSC67657 combined with inhibitor group and NSC67657 combined activator group were compared and analyzed. RESULTS: 20 µmol/L XAV-939 and 20 mmol/L LiCl could effectively inhibit and activate Wnt signalling pathway of HL-60 cells respectively, could significantly down- and up-regulate the expression of cyclinD1, TCF1 and c-Jun genes (P < 0.05) and proteins (P < 0.05); moreover, the number of CD10(+) HL-60 cells in these conditions was below 1%, no early apoptosis of HL-60 cells was found. In the simple NSC67657-treated groups, the expression of cyclinD1, TCF1 and c-Jun proteins was down-regulated (P < 0.05), and the percentage of CD14(+) HL-60 cells accounted for 62.13 ± 9.44; after the HL-60 cells were treated with XAV-939, the NSC67657 could more significantly down-regulate the expression of cyclinD1, TCF1 and c-Jun proteins and the percentage of CD14(+) HL-60 cell accounted for 84.17 ± 5.39%, as compared with simple NSC67657-treated group; as compared with blank controls group, the expression of cyclinD1, TCF1 and c-Jun proteins was more obviously down-regulated and the percentage of CD14(+) HL-60 cells decreased to 33.99 ± 8.37% in NSC67657 combined LiC1 streated group, but which were higher than those in simple NSC67657-treated group (P < 0.05). CONCLUSION: 20 µmol/L XAV-939 and 20 mmol/L LiCl as effective inhabitor and activator of Wnt signalling pathway respectively can significantly down- and up-regulate the expression of Wnt down-stream pathway target genes and proteins. The influence of XAV-939 and LiC1 on differentiation of HL-60 cells induced by NSC67657 suggests that Wnt signalling pathway plays a key role in monocyte differentiction of HL-60 cells induced by NSC67657.


Assuntos
Diferenciação Celular , Mesilatos/farmacologia , Monócitos/citologia , Esteroides/farmacologia , Via de Sinalização Wnt , Apoptose , Ciclina D1/metabolismo , Citometria de Fluxo , Células HL-60 , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo
19.
Am J Transl Res ; 7(9): 1660-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550465

RESUMO

Bone marrow stroma plays a critical role in the bone metastasis of breast cancer. Bone marrow-derived mesenchymal stem cells (BMSC) are critical to facilitate cancer progression. Human bone morphogenetic protein 9 (BMP9) is the most potent osteogenic factor and one of bone-stored growth factors involved in both promotion and inhibition of different cancers. However, it is unclear whether BMP9 correlates with the bone metastasis of breast cancer. This study was to evaluate the role of BMP9 in the interaction between BMSC and breast cancer cells (BCC). To determine whether BMP9 is able to block the tumor promoting effect of BMSC, an in vitro model was developed using breast cancer MDA-MB-231 cells co-cultured with bone marrow-derived mesenchymal stem cells HS-5 with-BMP9 overexpression. The expressions of metastasis-related genes were detected to identify important factors mediating the role of BMP9 in breast cancer cells. Results showed BMP9 could inhibit invasion and promote apoptosis of MDA-MB-231 cells. The expressions of interleukin-6 (IL-6), matrix metalloproteinase-2 (MMP-2) and monocyte chemoattratctant protein-1 (MCP-1) decreased in the MDA-MB-231 cells of BMP9 over-expression group, and the expressions of epithelial-mesenchymal transition (EMT)-related molecules was also reduced. On the other hand, the expression of stromal cell derived factor-1 (SDF-1) decreased in HS-5 cells of BMP9 over-expression group. Taken together, BMP9 is able to inhibit the migration and promote the apoptosis of breast cancer by regulating the interaction between MDA-MB-231 cells and HS-5 cells in which SDF-1/CXCR4-PI3K pathway and EMT are involved.

20.
J Biomed Nanotechnol ; 11(2): 236-44, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26349299

RESUMO

To determine the effects of surface modification on implant osseointegration in vivo, we first immobilized polydopamine onto 70-nm diameter TiO2 nanotubes as an intermediate layer, and then conjugated a 21 amino acid peptide sequence (the so-called "knuckle peptide") of bone morphogenetic protein-2 (BMP-2) onto the nanotubes created by electrochemical anodization. We inserted these implants into the tibiae of rabbits and measured the gene expression and bone formation around them. The successful fabrication of BMP-2 knuckle peptide was confirmed by contact angle measurement, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The histological features and the amount of bone fluorescence around the implants on non-decalcified sections were investigated at 3, 5, 8, and 12 weeks after implantation using traditional light and fluorescence microscopy, and the gene expression of alkaline phosphatase, osterix, collagen-I, and tartrate-resistant acid phosphatase was examined by real-time PCR at 1, 2, 3, 4, and 5 weeks after implantation. The results demonstrated a significant increase in bone-implant contact, quantity of fluorescence, and gene expression levels of the bone attached to implants with immobilized BMP-2 knuckle peptide compared with the other two control groups. In conclusion, the surface functionalization of TiO2 nanotubes with BMP-2 knuckle peptide was beneficial for osseointegration and this approach could be further developed to improve Ti-based implants for various applications.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Nanotubos , Osseointegração/efeitos dos fármacos , Próteses e Implantes , Titânio , Animais , Proteína Morfogenética Óssea 2/química , Adesão Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Coelhos , Propriedades de Superfície , Tíbia/cirurgia
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