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2.
Molecules ; 29(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38338407

RESUMO

Novel bamboo activated carbon (BAC) catalysts decorated with manganese oxides (MnOx) were prepared with varying MnOx contents through a facile one-step redox reaction. Due to the physical anchoring effect of the natural macropore structure for catalyst active components, homogeneous MnOx nanoparticles (NPs), and high specific surface area over catalyst surface, the BAC@MnOx-N (N = 1, 2, 3, 4, 5) catalyst shows encouraging adsorption and catalytic oxidation for indoor formaldehyde (HCHO) removal at room temperature. Dynamic adsorption and catalytic activity experiments were conducted. The higher Smicro (733 m2/g) and Vmicro/Vt (82.6%) of the BAC@MnOx-4 catalyst could facilitate its excellent saturated and breakthrough adsorption capacity (5.24 ± 0.42 mg/g, 2.43 ± 0.22 mg/g). The best performer against 2 ppm HCHO is BAC@MnOx-4 catalyst, exhibiting a maximum HCHO removal efficiency of 97% for 17 h without any deactivation as RH = 0, which is higher than those of other MnOx-based catalysts. The average oxidation state and in situ DRIFTS analysis reveal that abundant oxygen vacancies on the BAC@MnOx-4 catalyst could be identified as surface-active sites of decomposing HCHO into the intermediate species (dioxymethylene and formate). This study provides a potential approach to deposit MnOx nanoparticles onto the BAC surface, and this hybrid BAC@MnOx material is promising for indoor HCHO removal at room temperature.

3.
Front Plant Sci ; 14: 1256772, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954987

RESUMO

Bamboo is a natural vascular bundle (VB) reinforced composite material used in more than 10 fields such as construction and furniture. The nodes in bamboo are crucial to its mechanical properties, but understanding of its performance is limited by lack of knowledge about the three-dimensional (3D) structure of the node. This work aimed to non-destructively identify the multi-dimensional characteristics of the VB in a bamboo branched node (BN) using X-ray microtomography (µCT). The VB was segmented from the BN using deep learning combined with the Watershed algorithm. The 3D model reconstruction and characterization of the VB were also conducted. It was found that the structure of VBs showed significant changes along the height of the BN. The VBs formed a complex 3D structure, VBs of the culm are connected with those of the branch, and the connectivity of the conducting tissue and fibers was 88.91% and 99.95%, respectively. The conducting tissue and the fibers had similar shapes but varying thicknesses, which enabled VBs to perform both water transport and mechanical support functions. The volumes fraction of parenchyma, fibers, and conducting tissue in the BN were 61.3%, 35.3%, and 3.4%, respectively, but the tissue proportion of the different heights of the BN varied from each other. The nodal ridge was a mechanical weak point of the BN, with a maximum fibers proportion of 43.8%. This study contributes to understanding the relationship of VBs between the branch and the culm. It provides a structural perspective for understanding the mechanical properties of BN and a theoretical basis for optimizing bamboo utilization efficiency.

4.
Int J Biol Macromol ; 222(Pt A): 691-700, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36174859

RESUMO

As a renewable biological macromolecule with aromatic structure, lignin can serve as matrix substance to maintain cell wall integrity and is regarded as the natural biomass recalcitrance. Substantial differences in the cell wall lignin topochemistry between opposite (Ow) and compression wood (Cw) trachieds in Pinus bungeana Zucc. were visualized during [Emim][OAc] pretreatment at room temperature. The ionic liqiuds treatment induced a more obvious wall swelling for highly lignified Cw tracheids than that of Ow, while dynamic Raman spectra analysis indicated the higher lignin and carbohydrates removal for Ow tracheids. Raman imaging further revealed that both lignin and carbohydrates were dissolved simultaneously within the middle lamella and secondary wall of Ow and pretreatment has little effects on Cw tracheids wall. Moreover, it was demonstrated that lignin composition was the key factor to affect the composition dissolution. In particular, lignin G-units were selectively removed from cell corner middle lamella (52.3 %) and secondary wall (62.0 %) of Ow tracheids. When cotton fiber, as a reference was treated under the same conditions, lattice conversion moving from cellulose I to II occurred. The findings confirmed the important role of lignin compostion in the dissolution behavior of carbohydrate dominant tracheids wall.


Assuntos
Pinus , Madeira , Madeira/química , Lignina/química , Solubilidade , Pinus/química , Parede Celular/química , Celulose/química
5.
Oncol Res ; 26(1): 157-171, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28835317

RESUMO

This work aims to elucidate the effects and the potential underlying mechanisms of microRNA-216a-3p (miR-216a-3p) on the proliferation, migration, and invasion of gastric cancer (GC) cells. In this study, we revealed that the expression of miR-216a-3p was significantly elevated in GC tissues and cell lines. The different expression level of miR-216a-3p was firmly correlated with clinicopathological characteristics of GC patients. We next demonstrated that upregulation of miR-216a-3p could dramatically promote the ability of proliferation, migration, and invasion of GC cells using a series of experiments, whereas downregulation essentially inhibited these properties. Additionally, through bioinformatics analysis and biological approaches, we confirmed that runt-related transcription factor 1 (RUNX1) was a direct target of miR-216a-3p, and overexpression of RUNX1 could reverse the potential effect of miR-216a-3p on GC cells. Furthermore, mechanistic investigation using Western blot analysis showed that downregulation of RUNX1 by miR-216a-3p could stimulate the activation of NF-κB signaling pathway. In summary, this work proved that miR-216a-3p can promote GC cell proliferation, migration, and invasion via targeting RUNX1 and activating the NF-κB signaling pathway. Therefore, miR-216a-3p/RUNX1 could be a possible molecular target for innovative therapeutic agents against GC.


Assuntos
Adenocarcinoma/patologia , Subunidade alfa 2 de Fator de Ligação ao Core/biossíntese , MicroRNAs/genética , NF-kappa B/biossíntese , Neoplasias Gástricas/patologia , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , Invasividade Neoplásica/genética , Transdução de Sinais/genética , Neoplasias Gástricas/genética
6.
Oncotarget ; 8(47): 82728-82739, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-29137298

RESUMO

With no effective treatments available for most pancreatic cancer patients, pancreatic cancer continues to be one of the most difficult malignancies to treat. Oncolytic virus mediated-gene therapy has exhibited ubiquitous antitumor potential. In this study, we constructed a novel oncolytic vaccinia virus harboring the inhibitor of growth family member 4 gene (VV-ING4) to investigate its therapeutic efficacy alone or in combination with gemcitabine against pancreatic cancer cells in vitro and in vivo. ING4 expression was determined via quantitative real-time polymerase chain reaction (qPCR) and western blot. The cytotoxicity of VV-ING4 was measured using a cell proliferation assay. Both flow cytometry and western blot were applied to analyze the cell cycle and apoptosis. Furthermore, the combination inhibitory effect of VV-ING4 and gemcitabine was assessed using Chou-Talalay analysis in vitro and a BLAB/c mice model in vivo. We found that VV-ING4 significantly increases ING4 expression, displayed greater cytotoxic efficiency, and induced pancreatic cancer cell apoptosis and G2/M phase arrest. Additionally, the combination of VV-ING4 and gemcitabine synergistically effect in vitro and in vivo. Taken together, our data implicate VV-ING4 as a conceivable pancreatic cancer therapeutic candidate alone or in combination with gemcitabine.

7.
Carbohydr Polym ; 164: 127-135, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28325308

RESUMO

The core-shell structure of carbon encapsulated magnetic nanoparticles (CEMNs) displays unique properties. Enhancing the magnetization of iron core, in parallel, improving the encapsulation of carbon shell are the two major challenges in the synthesis of CEMNs. Inspired by efficient cellulose-dissolving system, carbon encapsulated magnetic nano-Fe3O4 particles (Fe3O4@C) with ∼10.0nm Fe3O4 cores and 1.9-3.3nm carbon shell, were successfully one-pot synthesized via a novel hydrothermal carbonization (HTC) process. The dissolving process in ionic liquids ([Emim]Ac and [Amim]Cl) completely cleaved the intra- and intermolecular H-bonds in cellulose, and favored the incorporation of Fe3O4 nanoparticles into the cellulose H-bonds systems during the regeneration process. Some stable linkages were formed in Fe3O4@C, taking Fe3O4 nanoparticles as a structure guiding agent. The morphology and properties of Fe3O4@C depended strongly on the type of carbon precursors and pyrolysis temperature. Well encapsulated nanostructure was obtained at HTC temperature 280°C, when [Emim]Ac-treated holocellulose was used as the carbon source. Meanwhile, the thickness of the amorphous shell and magnetization increased with HTC temperature. More importantly, a novel elements for understanding the growth mechanism for the Fe3O4@C composite under HTC conditions was proposed.

8.
Carbohydr Polym ; 153: 7-13, 2016 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-27561466

RESUMO

On the concept of biorefinery, hemicellulosic and lignin fractions were isolated from white-rot fungal Trametes velutina D10149 biodegraded poplar, and the structural modification was elucidated in detail according to the different incubation duration. Transversal-section Raman images showed that the fiber secondary walls were preferentially degraded, whereas the compound middle lamellae, including the cell corner regions, were mainly intact after 16 weeks incubation. More importantly, lignin and carbohydrates were simultaneously removed within the fiber secondary wall. From wet chemistry analysis, the yields and structural properties for both hemicellulosic and lignin fractions were not significantly altered. The synergistic effect of ligninolytic system finally obviously appeared after 16 weeks incubation, evidenced by the remarkable decrement of hemicellulose and lignin molecular weights. Additionally, the preferential degradation of S units in lignin biomacromolecule was further confirmed by composition analysis of cell wall phenolics and the integration of 2D NMR correlations in the aromatic region.


Assuntos
Lignina/química , Polissacarídeos/química , Populus/química , Trametes/metabolismo , Madeira/química , Biotransformação , Parede Celular/química , Parede Celular/metabolismo , Lignina/metabolismo , Polissacarídeos/metabolismo , Populus/metabolismo , Trametes/química , Madeira/metabolismo
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1734-9, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-30052382

RESUMO

As the skeleton substances of lignocellulosic biomass cell wall and the precursor of biofuels production, the research on cellulose structure, an important natural biomarcromolecules, attracts great attention. Considering its in situ features and higher resolution, Raman spectroscopy has been used to investigate the structure of cellulose molecular chain and cellulose aggregation structure at multi-scale. In this paper, the configurations and corresponding parameters of two types of Raman spectroscopy (Dispersive Raman and FT-Raman) were compared. Subsequently, the utilization of Raman spectroscopy in cellulose micro-distribution, cellulose enzyme hydrolysis, cellulose chain orientation and deformation, cellulose crystallinity and polymorphic transformation was discussed in detail. Given the existing deficiencies of the Raman spectroscopy when used to investigate the natural cellulose, some suggestions were proposed in order to promote the application of Raman spectroscopy to the research of natural macromolecular.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1899-1903, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-30053122

RESUMO

Density, which is closely relate with many physical and mechanical properties of bamboo, is one of the important indicators of bamboo material properties. Moreover, because of existing different moisture gradients in bamboo, the measured results of the density are different. Based on X-ray computed tomography (X-CT) technology, the divergent degree of the CT values of 7 different aged Moso bamboo was compared under oven-dried, air-dried and water-saturated conditions. Except for the 4-year-old and 10-year-old Moso bamboo, the CT values of other aged bamboos have minor differences with each other; the models for the measured CT values and the corresponding densities of Moso bamboo were respectively fitted under oven-dried, air-dried and water-saturated conditions. Meanwhile, the model was also fitted under different moisture gradients, which was composed by the measured CT values and the corresponding densities of Moso bamboo. Then the relations between the CT values andthe densitiesof 7 different aged Moso bamboo were systematically analyzed under single moisture content and three moisture gradients;the CT values were fitted under oven-dried condition, of which the radial positions are relative to the outer of Moso bamboo. According to the relation between the CT value and the density, the fitting curves explain the reasons for the radial density variations of 7 different aged Moso bamboo. Results show that the relations, which are fitted by the measured densities and the corresponding CT values of 7 different aged Moso bamboo under oven-dried, air-dried and water-saturated conditions, are good linear and the slopes of those models are approximate; the relation of the densities with the CT values for Moso bamboo is linear under different moisture gradients, moreover, which is rarely affected by moisture. The regression equation is: D=0.001 H+1.003 2, R2=0.968 3(D is the density, H is the CT value) and the determination coefficient of the validation model is: R2=0.974 3; there is no obvious variation between the densities of the inner and the outer, but not in middle part to 7 different aged Moso bamboo under oven-dried condition. To realize rapid detection on the densities of Moso bamboo under different moisture content, these results provide technical support and data reference. At the same time, X-ray computed tomography (X-CT) technology also puts forward a new feasible way for the further studies of bamboo material properties and structure.

11.
Microsc Microanal ; 21(5): 1304-13, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26358178

RESUMO

Structural organization of the plant cell wall is a key parameter for understanding anisotropic plant growth and mechanical behavior. Four imaging platforms were used to investigate the cell wall architecture of Miscanthus sinensis cv. internode tissue. Using transmission electron microscopy with potassium permanganate, we found a great degree of inhomogeneity in the layering structure (4-9 layers) of the sclerenchymatic fiber (Sf). However, the xylem vessel showed a single layer. Atomic force microscopy images revealed that the cellulose microfibrils (Mfs) deposited in the primary wall of the protoxylem vessel (Pxv) were disordered, while the secondary wall was composed of Mfs oriented in parallel in the cross and longitudinal section. Furthermore, Raman spectroscopy images indicated no variation in the Mf orientation of Pxv and the Mfs in Pxv were oriented more perpendicular to the cell axis than that of Sfs. Based on the integrated results, we have proposed an architectural model of Pxv composed of two layers: an outermost primary wall composed of a meshwork of Mfs and inner secondary wall containing parallel Mfs. This proposed model will support future ultrastructural analysis of plant cell walls in heterogeneous tissues, an area of increasing scientific interest particularly for liquid biofuel processing.


Assuntos
Parede Celular/química , Parede Celular/ultraestrutura , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Transmissão/métodos , Poaceae/química , Poaceae/ultraestrutura , Análise Espectral Raman/métodos , Celulose/análise , Celulose/ultraestrutura , Microfibrilas/química , Microfibrilas/ultraestrutura
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3519-23, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26964242

RESUMO

The wood property and production process affect quality of Guqin. At the same time, Guqin shape with cavity layout relations to the improvement of Guqin technology and inheritance, so it's very important to get the internal cavity characteristics and parameters on the condition of non-destructive the structure of Guqin. The image of interior structure in Guqin was investigated by overall scanning based on non-destructive testing technology of computed tomography, which texture of faceplate, connection method between faceplate and soleplate and interior defects were studied. The three-dimensional reconstruction of Guqin cavity was achieved through Mimics software of surface rendering method and put the two-dimensional CT tomography images convert into three-dimensional, which more complete show interior structural form in Guqin, and finally the parameter of cavity dimensions was obtained. Experimental research shows that there is significant difference in Guqin interior structure between Zhong-ni and Luo-xia type, in which the fluctuation of the interior surfacein Zhong-ni type's is larger than that in Luo-xia type; the interior volume of Zhong-ni typeis less than that of Luo-xia type, especially in Guqin neck. The accurate internal information of Guqin obtained through the computed tomography (CT) technology will provide technical support for the Guqin manufacture craft and the quality examination, as well as provide the reference in the aspect of non-destructive testing for other traditional precious internal structure research.

13.
Cell Biochem Biophys ; 71(1): 291-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25358405

RESUMO

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) shows promising result in cancer therapy and induces apoptosis in a wide variety of tumor cells, without causing toxicity to normal cells. However, many tumor cells including acute myeloid leukemia (AML) showed certain degrees of resistance to TRAIL and the mechanism remains largely unknown. Embelin is a potent XIAP inhibitor which has been shown to inhibit the proliferation of tumor cells and cause cell apoptosis. In this study, we investigated the effects of Embelin on the TRAIL-induced apoptosis and the underlying mechanism. Here, we chose an adenovirus vector as the expression vector for TRAIL, which was named Ad-TRAIL. The results in vitro showed that the co-treatment of Embelin and Ad-TRAIL has synergistically suppressed the proliferation of AML cells. Embelin has the ability to enhance TRAIL-induced apoptosis and activate caspase pathway. More interestingly, we found that the underlying mechanism for these talent skills of Embelin is through reducing the TRAIL-mediated activation of NF-κB and decreasing its transcriptional activity. Furthermore, our results in vivo suggest that combined therapy of Embelin and Ad-TRAIL caused significant growth inhibition of HL-60 xenograft tumors. Our results suggested that Embelin could sensitize AML cell to TRAIL through the repression of NF-κB signal pathway in vitro and in vivo, and combined therapy of Ad-TRAIL and Embelin may be the attractive candidate for clinical application in treatment of AML.


Assuntos
Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Leucemia Mieloide Aguda/patologia , NF-kappa B/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/antagonistas & inibidores , Adenoviridae/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Feminino , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , Camundongos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1698-701, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25358191

RESUMO

X-ray diffraction technology was used to rapidly predict variation in microfibril angle (MFA) in Dendrocalamus fari- X-ray diffraction technology was used to rapidly predict variation in microfibril angle (MFA) in Dendrocalamus farinosus. The results show that there is little variation in MFA with bamboo age from 2a to 5e, and MFA of 3a is at the maximum with the value of 8.521 degrees. The average value of MFA of 2a or 3a is greater than 4a or 5a with absolute differences less than 0.10 degrees. MFA of base, middle and upper position respectively are 8.499 degrees, 8.497 degrees and 8.483 degrees with coefficient of variation about 5%. There is an increasing tendency from the periphery to the inner of bamboo culms. Variance analysis indicates that MFA is highly sensitive to radial position, but insensitive to bamboo age and longitudinal position. The correlation coefficient of longitudinal strength and modulus of elasticity (MOE) is 0.57. MFA was responsible for 35% and 43% of the variation found in longitudinal strength and MOE respectively, which means MFA has a certain extent effect on mechanical properties.


Assuntos
Microfibrilas/fisiologia , Poaceae/anatomia & histologia , Difração de Raios X , Análise de Variância , Resistência à Tração
15.
Bioresour Technol ; 167: 94-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24971950

RESUMO

Combustion characteristics of biomass are very important to directly utilize as an energy resource. Bamboo was carbonized using a XD-1200N muffle furnace in the nitrogen environment and its combustion characteristics were investigated. Results showed that bamboo-biochars had better combustion characteristics compared to bamboo materials, such as a lower content of moisture and volatiles, a higher energy density, HHV and EHC, a lower H/C and O/C ratios and a shorter TTI. Characteristic peak of bamboo-biochars shifted to higher temperature in thermal decomposition process, indicating a more steady-state burning and a higher combustion efficiency. Bamboo-biochars had a low content of S and N, which was helpful to decrease pollutant emissions. A higher content of K and Na was observed in the ash of bamboo-biochars, resulting in slagging, fouling, corrosion and agglomeration. The data from this research will be very helpful to efficiently design and operate its combustion systems.


Assuntos
Bambusa/química , Carvão Vegetal/química , Temperatura Alta , Carbono/análise , Hidrogênio/análise , Oxigênio/análise , Fatores de Tempo
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(12): 3380-4, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25881443

RESUMO

Density is one of the important physical indicators of bamboo, associated with its many physical and mechanical properties. The temporal and spatial variation of density in 2-5-year-old Dendrocalamus farinosus were measured using computed tomography (CT) technology. Scanning parameters were obtained through orthogonal design. The relationship of air-dry density (Y) and the corresponding CT values (X) was established and verified through regression analysis, which presents an approximate linear relationship between them. The linear equation is Y=0.001X+1.148. The radial and longitudinal variation of density was determined by the regression model. This study provides a new method to measure bamboo density efficiently and accurately, and also put forward a new thought to further study structure and characteristics of bamboo.


Assuntos
Poaceae/crescimento & desenvolvimento , Tomografia Computadorizada por Raios X , Modelos Teóricos , Análise de Regressão , Análise Espaço-Temporal
17.
Hepatogastroenterology ; 60(125): 1169-73, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23803380

RESUMO

BACKGROUND/AIMS: To investigate the effects of K-ras siRNA on pancreatic cancer cells and the expression levels of GLI1, E-cadherin and vimentin in pancreatic cancer cells transfected with K-ras siRNA. METHODOLOGY: Ppancreatic cancer cells PANC-1 were transfected with K-ras siRNA. Growth inhibition ratio of the cells were measured by MTT assay, apoptosis was detected by flow cytometery, expression level of GLI1, E-cadherin and vimentin were detected by Western blot. RESULTS: The expression of K-ras protein was efficiently inhibited by K-ras siRNA in PANC-1 cells. The growth inhibition rates of the cells were significantly different to the control groups. Apoptosis rates were significantly different with that of control group. The expression of GLI1 was significantly down-regulated, E-cadherin was up-regulated, while vimentin was also down-regulated in K-ras siRNA transfected cells compared with that of control groups. CONCLUSIONS: Inhibiting K-ras signaling by K-ras siRNA can inhibit proliferation and induce apoptosis of pancreatic cancer cells, down-regulate GLI1's and vimentin's expression, and up-regulate E-cadherin's expression. Inhibiting K-ras signaling by K-ras siRNA may reduce epithelial to mesenchymal transition of pancreatic cancer cell PANC-1.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais/fisiologia , Proteínas ras/fisiologia , Apoptose , Caderinas/análise , Linhagem Celular Tumoral , Humanos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras) , Vimentina/análise , Proteínas ras/antagonistas & inibidores
18.
Oncol Rep ; 29(6): 2401-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23563640

RESUMO

Curcumin, a phenolic compound extracted from Zingiberaceae turmeric, has strong anti-inflammatory, antioxidant and antitumor properties. However, the anticarcinogenic mechanism of curcumin has yet to be fully elucidated. Epithelial-mesenchymal transition (EMT) induced by transforming growth factor-ß1 (TGF-ß1) is involved in the promotion of tumor invasion and metastasis, and is closely related to the drug resistance of tumor cells. The abnormal activation of Hedgehog signaling also plays an important role in tumorigenesis and metastasis. In order to investigate whether curcumin can reverse the TGF-ß1-stimulated EMT of pancreatic cancer PANC-1 cells, and its possible mechanism, the pancreatic cancer cell line PANC-1 was stimulated with TGF-ß1 (5 ng/ml) for 7 days to induce formation of EMT, and the TGF-ß1-stimulated PANC-1 cells were treated with different concentrations of curcumin (10, 20 and 30 µmol/ml) for 48 h. The growth inhibition rate of the cells was measured by MTT assay, apoptosis was detected by flow cytometry, the expression levels of Shh, GLI1, E-cadherin and vimentin were detected by western blot analysis, and cell invasion and migration ability were examined by transwell cell invasion assay and wound healing assay. Following stimulation with TGF-ß1, the expression levels of Shh, GLI1 and vimentin in the TGF-ß1-stimulated group were significantly increased, compared with those in the control group (P<0.01, respectively). The expression levels of E-cadherin in the TGF-ß1-stimulated group were significantly decreased, compared with those in the control group (P<0.01). The TGF-ß1-stimulated PANC-1 cells were treated with curcumin and the results showed that curcumin significantly inhibited TGF-ß1-stimulated PANC-1 cell proliferation and induced apoptosis, compared with other groups (P<0.01), and the expression levels of Shh, GLI1 and vimentin in the curcumin-treated group were significantly decreased compared with those in the control group (P<0.01, respectively). The expression level of E-cadherin in the curcumin-treated group was significantly increased compared with that in the control group (P<0.01). Cell invasion in the curcumin-treated group (30 µmol/ml) was significantly decreased compared with that in the control group (P<0.01). The scratch wounds in the curcumin-treated group healed slower compared with those in the control group (P<0.01). Curcumin significantly inhibited the invasion and migration of TGF-ß1-stimulated PANC-1 cells. These results indicate that curcumin can inhibit the proliferation of TGF-ß1-stimulated PANC-1 cells, it can induce apoptosis, and reverse the EMT. The possible underlying molecular mechanisms are through inhibition of the Shh-GLI1 signaling pathway.


Assuntos
Anticarcinógenos/farmacologia , Curcumina/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Antígenos CD , Apoptose , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/fisiologia , Vimentina/metabolismo , Proteína GLI1 em Dedos de Zinco
19.
Mol Med Rep ; 6(6): 1267-70, 2012 12.
Artigo em Inglês | MEDLINE | ID: mdl-23023821

RESUMO

Curcumin is the major component of the spice turmeric, extracted from the rhizomes of the plant Curcuma longa. It exerts a number of therapeutic effects, including the inhibition of cancer cell proliferation. However, the anti-carcinogenic mechanism of curcumin has not been fully elucidated. Triple-negative breast cancer (TNBC), which lacks expression of the estrogen receptor (ER), progesterone receptor (PR) and epidermal growth factor receptor 2 (HER2/EGFR2), is an aggressive breast cancer phenotype with a poor prognosis. In this study, we investigated the effects of curcumin on triple-negative breast cancer cells and the possible molecular mechanisms. The MDA-MB-231 TNBC cells were treated with curcumin, the growth inhibition ratio of the cells was measured by MTT assay, apoptosis was detected by flow cytometry and the expression levels of extracellular regulated protein kinase (ERK1/2), pERK1/2, EGFR and pEGFR were detected by western blotting. After treatment with different concentrations of curcumin, the growth inhibition rates of the MDA-MB-231 breast cancer cells of the 30 µmol/ml curcumin-treated group were significantly different from those of the other groups. The level of apoptosis of the curcumin-treated group (26.34%) was significantly different from that of the control group (2.76%). The expression levels of pERK1/2 and pEGFR in the curcumin-treated group were significantly decreased compared with those of the control group. These results indicate that curcumin is able to inhibit the proliferation of TNBC cells. Inhibition of the EGFR signaling pathway is the likely underlying molecular mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Curcumina/farmacologia , Receptores de Estrogênio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Receptores de Estrogênio/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(7): 1935-8, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-23016357

RESUMO

CT is widespread non-destructive detection technique for wood materials, and the density measurement is a key role during this application. In the present report, the use of CT for air-dry density measurement of wood and bamboo is described. The authors found that there were marked linear correlations between air-dry density (0.303-1.061 g x cm(-3)) of 24 kinds of woods and their respective CT value, as well as 25 kinds of lignin materials (including 24 kinds of woods and 1 kind of bamboo) and the CT value, both with correlation coefficient of 0.99, which belonged to the CT technological breakthrough for wood quantitative detection These research results show that CT is an appropriate way to measure density for wood and bamboo, and would provide technical support for CT used in the field of wood science research and wood processing.


Assuntos
Bambusa , Tomografia Computadorizada por Raios X , Madeira , Lignina
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