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1.
Heliyon ; 10(10): e30660, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38774334

RESUMO

Understanding the precursors leading to rock fracture is crucial for ensuring safety in mining and geotechnical engineering projects. To effectively discern these precursors, a collaborative monitoring approach that integrates multiple sources of information is imperative. This paper considered a rock multi-parameter monitoring loading system, incorporating infrared radiation and acoustic emission monitoring technologies to simultaneously track the rock fracture process. The study delves into the spatiotemporal evolution patterns of infrared radiation and acoustic emission in rock under loading. Utilizing stress, cumulative acoustic emission count, and average infrared radiation temperature (AIRT), the paper establishes a comprehensive evaluation model termed "acoustic-thermal-stress" fusion information, employing principal component analysis (PCA). The research reveals that the sensitivity to rock sample damage response follows the sequence of cumulative acoustic emission count, AIRT, and stress. Furthermore, a novel method for identifying rock fracture precursors is proposed, based on the first derivative of the comprehensive evaluation model. This method addresses the limitations of single physical field information, enhancing the robustness of monitoring data. It determines the average stress level of fracture precursors to be 0.77σmax. Subsequently, the study defines the probability function of rock damage during loading and fracture, enabling the realization of probability-based warnings for rock fracture. This approach introduces a new perspective on rock fracture prediction, significantly contributing to safety monitoring and warning systems in mine safety and geotechnical engineering. The findings of this research hold paramount engineering significance, offering valuable insights for enhancing safety measures in such projects.

2.
Heliyon ; 9(11): e22277, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38053877

RESUMO

This study aims to investigate the evolution patterns of fluidity and rheological properties of AASCM under varying dosages of foaming agent and particle sizes of filling aggregate. The flow characteristics of AASCM are significantly affected by the filling aggregate's size and the foaming agent's dosage. Specifically, an increase in filling aggregate size (D(4,3) ϵ [26 µm, 69 µm]) enhances the fluidity of foamed AASCM, while an increase in foaming agent dosage reduces fluidity. These observed variations can be attributed to the presence of particle voids, the specific surface area of the aggregate, as well as the quantity and spatial distribution of bubbles within the slurry. A bubble-particle packing model is established, and by calibrating the simulation error coefficient to 1.1, the study investigates the evolution of water film thickness (WFT) in foamed AASCM with slurry expansion degree. It is observed that bubbles in the slurry affect the fluidity by altering the overall compactness and specific surface area of the foamed slurry, subsequently modifying the WFT.

3.
Environ Sci Pollut Res Int ; 30(52): 111936-111946, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37821737

RESUMO

Backfill mining can effectively alleviate the problems of surface collapse and ecological water pollution, in which the mechanical properties of backfill materials, including coal gangue and coal fly ash, have a decisive role in the effect of filling mining. In this study, we analyze the permeability characteristics of coal gangue filler through a set of homemade percolation test systems and introduce fractal characteristics to investigate the key factors affecting percolation in complex pores of broken coal gangue. The results indicate that the fractal dimensions of crushed coal gangue particles show an increasing trend with increasing axial loading and that the variation range is from 2.15647 to 2.58933. The coal fly ash concentration has a positive relationship with the acceleration factor. The permeability of crushed coal gangue follows a hierarchical distribution law and the permeability changes in the magnitude range of 10-11 ~ 10-9 m2. The fractal dimension is inversely related to the permeability of crushed coal gangue. The experimental results show that the coal gangue will be further crushed and that adding a certain concentration of coal fly ash can achieve a better water barrier, which provides theoretical support and engineering significance for the stability analysis of geological engineering and backfill mining technology.


Assuntos
Cinza de Carvão , Fractais , Cinza de Carvão/análise , Carvão Mineral/análise , Mineração , Água
4.
Nanotechnology ; 34(32)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37141885

RESUMO

Transition metal carbides show remarkable catalysis for MgH2, and the addition of carbon materials can attach excellent cycling stability. In this paper, Mg-doped with transition metal carbides (TiC) and graphene (G) composite (denoted as Mg-TiC-G) is designed to assess the influence of TiC and graphene on the hydrogen storage performance of MgH2. The as-prepared Mg-TiC-G samples showed favorable dehydrogenation kinetics compared to the pristine Mg system. After adding TiC and graphene, the dehydrogenation activation energy of MgH2decreases from 128.4 to 111.2 kJ mol-1. The peak desorption temperature of MgH2doped with TiC and graphene is 326.5 °C, which is 26.3 °C lower than the pure Mg. The improved dehydrogenation performance of Mg-TiC-G composites is attributed to synergistic effects between catalysis and confinement.

5.
Molecules ; 28(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36985844

RESUMO

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

6.
ACS Omega ; 7(31): 27090-27101, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35967027

RESUMO

This study aimed to prevent water flow in microcracks and simultaneously achieve CO2 capture during grouting (CCG). Using sodium silicate (SS) as the primary material, the microcracks were grouted by a two-step approach. The low-initial-viscosity (5 mPa s) SS was first saturated within the microcracks followed by CO2 injection at 2 MPa. Through CO2 dissolution, silica gel was developed and tolerated a hydraulic pressure of up to 5.5 MPa. The effects of aquifer ions (Na+, Ca2+, Mg2+, HCO3 -, and SO4 2-) were equally evaluated at harsh conditions, and it was found that the strength of the silica gel was reduced, which was caused by salting out, low CO2 solubility, and precipitation. As a result, the hydraulic pressure was reduced to as low as 3 MPa. After 210 days, 16% of the silica gels (without ion inclusion) were reversible to the liquid phase, where a similar effect was found in the cases of Na+ and Mg2+ ions. The degradation increased with more Ca2+ ions (up to 55%) and decreased with more HCO3 - and SO4 2- ions. Microcracks grouted with CCG extended the CO2 utilization in grouting application. Combined with the effect of dissolved ions, the proposed approach is feasible in the field implementation for underground engineering under water bodies.

7.
Materials (Basel) ; 14(17)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34501157

RESUMO

An ultrasensitive enzyme-free glucose sensor was facilely prepared by electrodepositing three-dimensional dendritic Cu on a room temperature exfoliated graphite-derived film (RTEG-F). An excellent electrocatalytic performance was demonstrated for glucose by using Cu/RTEG-F as an electrode. In terms of the high conductivity of RTEG-F and the good catalytic activity of the dendritic Cu structures, the sensor demonstrates high sensitivities of 23.237 mA/mM/cm2, R2 = 0.990, and 10.098 mA/mM/cm2, R2 = 0.999, corresponding to the concentration of glucose ranging from 0.025 mM to 1.0 mM and 1.0 mM to 2.7 mM, respectively, and the detection limit is 0.68 µM. In addition, the Cu/RTEG-F electrode demonstrates excellent anti-interference to interfering species and a high stability. Our work provides a new idea for the preparation of high-performance electrochemical enzyme-free glucose sensor.

8.
Chem Asian J ; 16(21): 3363-3370, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34423898

RESUMO

With the increasingly strict standard for sulfur content in fuel, it is necessary to develop high-efficiency catalyst for extractive and catalytic oxidative desulfurization systems (ECODS). Herein, a series of three remarkable complexes H3 PMo(12-n) Wn O40 @rht-MOF-1 (1 a, n=1; 2 a, n=2; 3 a, n=3) have been designed and prepared. Complexes 1 a, 2 a and 3 a were characterized by single-crystal X-ray diffraction and FT-IR, PXRD, SEM, N2 adsorption-desorption isotherms, etc. Upon complex 3 a was applied as catalyst, it exhibited remarkably high catalytic activity in the ECODS reactions of aromatic sulfur compounds under optimal conditions. On the basis of its excellent heterogeneity, the catalyst could be recycled for nine consecutive cycles without significant losing of activity centers. Then, the reaction kinetics and mechanism were investigated and the activation energy have been calculated and discussed. Further, the complex 3 a is employed to catalyze the ODS of commercial diesel oil. As a result, the desulfurization efficiency reached 90%. These results provided important structure data for study the structure-property relationship and potential heterogeneous catalyst applied in ODS in industry.

9.
ACS Omega ; 6(14): 9868-9875, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33869967

RESUMO

The utilization of industrial waste as renewable resources is an essential issue of sustainable development. Kish graphite is a precipitate of excess carbon generated during the cooling of molten iron and one of the byproducts associated with steel slags. The scale-up recycling of kish graphite from steelmaking slags is a promising way to develop natural graphite alternatives. However, only one means cannot work efficiently because of the unusual occurrence of associated impurities; combining multiple separation methods is the solution. In this paper, we proposed an integrated beneficiation process, pneumatic separation-flotation-sonication-magnetic separation, to recycle kish graphite flakes with a high graphitization degree and investigated the sorption performance of various oils on kish-based expanded graphite. The new process avoided shortages such as the sediments of iron particles in the flotation cell and the loss of clean graphite in the magnetic separation. Consequently, the carbon content of kish graphite reached ∼95% after separation and >99% after acid leaching. The macroscopic structural defects of kish particles created more active sites, made the intercalation of KG-GICs faster, and yielded better-staged compounds. The kish graphite-based expanded graphite presented an octopus-like shape and exhibited an expansion volume of ∼150 mL/g. Furthermore, the developed macropore structure of the obtained kish graphite-based expanded graphite led to a superior sorption performance for oils. This work supplies one feasible and promising way to recycle kish graphite from steelmaking slags and use it.

10.
J Tradit Chin Med ; 41(1): 117-124, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33522204

RESUMO

OBJECTIVE: To evaluate the efficacy of Huanglian root decoction (, HLD) on kidney injury in rat's model of metabolic syndrome (MetS), and investigate the possible mechanism. METHODS: A fructose-induced MetS rat model and human renal tubular epithelial cell-line model were used to compare the efficacy of HLD with that of berberine and tauroursodeoxycholic acid (TUDCA). Blood pressure, biochemical parameters, histopathological changes and the expression levels of oxidative stress markers were evaluated in the animal model at the end of an 8-week treatment regimen. Oxidative stress markers and molecules of the signal pathway of endoplasmic reticulum (ER) stress were evaluated in the human cell-line model. RESULTS: Levels of fasting insulin, systolic blood pressure and diastolic blood pressure were significantly decreased in rats in the Huanglian group compared to those in the MetS group (P < 0.05). Rats treated with HLD and TUDCA exhibited a significant reduction in blood levels of malondialdehyde compared to those in rats in the MetS group (P < 0.05). Significant increases in glutathione peroxidase in human tubular epithelial cells was found in the Huanglian group compared to that in the MetS group (14.02 vs 18.31, P < 0.05). The mRNA expression of protein kinase RNA-like endoplasmic reticulum kinase and eukaryotic translation initiation factor 2 α decreased significantly in Huanglian groups compared with that in the MetS group. CONCLUSION: HLD has therapeutic efficacy on kidney injury in the MetS rat's model, and is non-inferior to berberine and TUDCA.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Nefropatias/tratamento farmacológico , Síndrome Metabólica/complicações , Animais , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos , Rim/efeitos dos fármacos , Rim/lesões , Rim/metabolismo , Nefropatias/etiologia , Nefropatias/genética , Nefropatias/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/química , Ratos , Ratos Wistar
12.
Molecules ; 25(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979052

RESUMO

This study aims at investigating the interaction and kinetics behavior of the co-gasification of digestate and lignite. The co-pyrolysis performances of digestate and lignite blended by dry process were better than that blended by wet process, while the wet-blending process could improve the performance in co-gasification stage because of the larger pore diameter and pore volume. When anaerobic digestion (AD) time was 40 days, the synergistic interaction between digestate and lignite were the most remarkable based on the results of thermogravimetric analysis (TG) and the experiments in the lab-scale downdraft fixed bed gasifier. Kinetics study showed that the increase of AD time and the addition of digestate in lignite decreased the activation energy of the co-gasification reaction.


Assuntos
Anaerobiose , Cinética , Pirólise , Termogravimetria
13.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(1): 37-42, 2019 Jan 30.
Artigo em Chinês | MEDLINE | ID: mdl-30770689

RESUMO

Cancer therapy with accelerated proton or heavy ion beam is the most advanced radiotherapy technology, which is recognized by the international community at present. It is of great practical significance to study the medical proton and heavy ion accelerators and the radiotherapy technology, in order to promote the development of the advanced medical radiotherapy equipments and improve the quality of life of cancer patients in China. After a brief overview of cancer therapy with proton and heavy ion beam, this paper summarized and analyzed the application status of medical proton accelerators and medical heavy ion accelerators at home and abroad, and finally put forward the future development trends of medical proton and heavy ion accelerators and the radiotherapy technology, it can provide a reference for the progress and development strategies of the advanced radiotherapy equipments in China.


Assuntos
Íons Pesados , Neoplasias , Terapia com Prótons , Prótons , China , Humanos , Neoplasias/terapia , Aceleradores de Partículas , Qualidade de Vida
14.
Eur J Pharmacol ; 807: 138-143, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28300591

RESUMO

Breast cancer is the most frequently occurring cancer in women worldwide, microRNAs (miRNAs) play critical role in the initiation and progression of breast cancer. Here, we studied the effect of miR-455 on cell proliferation of breast cancer, and found that miR-455 was downregulated in breast cancer tissues and cells. Its overexpression inhibited cell proliferation, whereas its knockdown promoted cell proliferation of breast cancer. We found a Cdc2-related protein kinase CDK14 was the target of miR-455, when the 3'UTR of CDK14 was cloned into luciferase reporter vector and transfected into cells, miR-455 mimic could inhibit the luciferase activity in a dose-dependent manner, miR-455 inhibitor increased the luciferase activity, but the mutant miR-455 mimic couldn't change the luciferase activity, suggesting miR-455 directly bound to the 3'UTR of CDK14. Meanwhile, we also found miR-455 inhibited Cyclin D1 expression and promoted p21 expression, confirming miR-455 inhibited cell proliferation. Double knockdown of miR-455 and CDK14 inhibited the proliferation of breast cancer cell, confirming miR-455 inhibiting cell proliferation by targeting CDK14. Moreover, miR-455 levels were negatively correlated with CDK14 levels in breast cancer tissues. Our finding revealed miR-455 inhibits breast cancer cell proliferation through targeting CDK14, it might be a target for breast cancer therapy.


Assuntos
Neoplasias da Mama/patologia , Quinases Ciclina-Dependentes/genética , MicroRNAs/genética , Regiões 3' não Traduzidas/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/genética , Humanos
15.
Drug Deliv ; 23(7): 2410-2418, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25564965

RESUMO

As with many other hydrophobic anticancer agents, 20(S)-protopanaxadiol (PPD) has a very low oral bioavailability. In this study, a precipitation-combined ultrasonication technique was used to prepare PPD nanosuspensions. The mean particle size of the nanosuspensions was approximately 222 ± 12 nm, the drug payload achieved 50% after lyophilization and the maximum PPD concentration can reach 100 mg/ml, which is over 30 000 times the solubility of PPD in aqueous solution (3 µg/ml). After oral administration, the Cmax and AUClast values of PPD nanosuspensions were approximately 3.66-fold and 3.48-fold as those of PPD coarse suspensions, respectively. In contrast to the free drug solution, PPD nanosuspensions showed higher in vitro anti-tumor activity against HepG-2 cells (an IC50 value of 1.40 versus 5.83 µg/ml at 24 h, p < 0.01). The in vivo study in H22-tumor-bearing mice demonstrated that PPD nanosuspensions showed good anti-tumor efficacy with an inhibition rate of 79.47% at 100 mg/kg, while 50 mg/kg of cyclophosphamide was displayed as positive control, and the inhibition rate was 87.81%. Considering the highest drug payload, oral bioavailability reported so far, significant anti-tumor efficacy and excellent safety of encapsulated drugs, PPD nanosuspensions could be used in potential effective strategies for anticancer therapy; further investigation is ongoing.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Sapogeninas/administração & dosagem , Sapogeninas/farmacologia , Administração Oral , Animais , Antineoplásicos/química , Disponibilidade Biológica , Células Hep G2 , Humanos , Camundongos , Sapogeninas/química , Suspensões
16.
Med Oncol ; 32(1): 338, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25452171

RESUMO

Cyclin D1 (CCND1) plays essential roles in cancer progression. In this study, CCND1 expression patterns in 211 cases of resected gastric adenocarcinoma (RGA) tissue were determined by immunohistochemistry, and the association between CCND1 expression levels and RGA prognosis was analyzed. RGA tissues displayed differential CCND1 expression (high expression, 52.1 %; n = 110, and low expression, 47.9 %; n = 101). CCND1 expression levels were related with median overall survival time (MST). MST in patients with high CCND1 expression was 43 months, whereas with low CCND1 expression it was 62 months (P = 0.013). When data were stratified by postoperative treatments and CCND1 expression levels, the MST for patients treated with fluoropyrimidine plus platinum (n = 140) was significantly longer than for those treated with fluoropyrimidine only (n = 71) in both high and low CCND1 expression groups (65.0 vs. 29.0 months, P = 0.041; and 74.5 vs. 33.0 months, P = 0.003, respectively). Cox multivariate analyses further confirmed that high CCND1 expression was related with poor prognosis in both treatment groups [hazard ratio (HR) 1.91, 95 % confidence interval (CI) 1.12-3.23; P = 0.017, and HR 2.14, 95 % CI 1.08-4.25; P = 0.029] and that fluoropyrimidine plus platinum was more effective than fluoropyrimidine only in high CCND1 (HR 0.47, 95 % CI 0.28-0.78; P = 0.004) and low CCND1 (HR 0.44; 95 % CI 0.23-0.82; P = 0.01) expression patients. Therefore, CCND1 may be used as a prognostic biomarker for patients with RGA.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/análise , Ciclina D1/biossíntese , Neoplasias Gástricas/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adulto , Idoso , Ciclina D1/análise , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade
17.
Clin Exp Nephrol ; 17(2): 304-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23053591

RESUMO

BACKGROUND: Good outcomes after renal transplantation are dependent on effective immunosuppression while minimizing infection. Alemtuzumab (Campath or Campath-1H) is an anti-CD52 humanized monoclonal IgG1 antibody which induces rapid and sustained depletion of circulating lymphocytes and has been effectively used as an immunosuppressant in post-transplant induction therapy. METHODS: We used the ImmuKnow assay to compare cell-mediated immune function in renal transplant patients treated with alemtuzumab or with conventional immunosuppressive tri-therapy. The ImmuKnow method determines the levels of adenosine triphosphate (ATP) released from CD4 cells following stimulation with a mitogen. RESULTS: We showed a statistically significant difference in the distribution of outcome after transplantation between the conventional and the Campath groups (P = 0.010). A significantly higher number of patients treated with alemtuzumab induction therapy were stable after transplantation compared to those treated with conventional immunosuppressive tri-therapy (96.6 vs. 75.7 %). ATP values were significantly higher in the conventional group compared to the Campath group at 180 days after transplantation (P < 0.001). ATP levels did not change significantly over time in clinically stable kidney recipients treated with alemtuzumab induction therapy (P = 0.554). CONCLUSIONS: The ImmuKnow assay is a useful tool for evaluating the global immune response in alemtuzumab-treated renal transplant patients. Alemtuzumab-depleting induction therapy remains effective for at least 180 days.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Imunidade Celular/efeitos dos fármacos , Imunoensaio/métodos , Terapia de Imunossupressão/métodos , Transplante de Rim/imunologia , Trifosfato de Adenosina/sangue , Adolescente , Adulto , Alemtuzumab , Linfócitos T CD4-Positivos/metabolismo , Creatinina/sangue , Feminino , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Fito-Hemaglutininas/farmacologia , Uremia/cirurgia , Adulto Jovem
18.
Environ Monit Assess ; 185(4): 3037-48, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22961327

RESUMO

A method based on headspace (HS) sampling coupling with portable gas chromatography (GC) with photo ionization detector (PID) was developed for rapid determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) in soils. Optimal conditions for HS gas sampling procedure were determined, and the influence of soil organic matter on the recovery of BTEX from soil was investigated using five representative Chinese soils. The results showed that the HS-portable-GC-PID method could be effectively operated at ambient temperature, and the addition of 15 ml of saturated NaCl solution in a 40-ml sampling vial and 60 s of shaking time for sample solution were optimum for the HS gas sampling procedure. The recoveries of each BTEX in soils ranged from 87.2 to 105.1 %, with relative standard deviations varying from 5.3 to 7.8 %. Good linearity was obtained for all BTEX compounds, and the detection limits were in the 0.1 to 0.8 µg kg(-1) range. Soil organic matter was identified as one of the principal elements that affect the HS gas sampling of BTEX in soils. The HS-portable-GC-PID method was successfully applied for field determination of benzene and toluene in soils of a former chemical plant in Jilin City, northeast China. Considering its satisfactory repeatability and reproducibility and particular suitability to be operated in ambient environment, HS sampling coupling with portable GC-PID is, therefore, recommended to be a suitable screening tool for rapid on-site determination of BTEX in soils.


Assuntos
Cromatografia Gasosa/métodos , Monitoramento Ambiental/instrumentação , Poluentes do Solo/análise , Benzeno/análise , Derivados de Benzeno/análise , China , Monitoramento Ambiental/métodos , Solo/química , Tolueno/análise , Xilenos/análise
19.
Mol Cancer ; 11: 79, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-23083134

RESUMO

BACKGROUND: Patients with invasive breast ductal carcinoma (IBDC) with metastasis have a very poor prognosis. Little is known about the synergistic action of growth and inflammatory factors in IBDC metastases. METHODS: The expression of activated extracellular signal-regulated kinase1/2 (phosphorylated or p-ERK1/2) was analyzed by immunohistochemistry in IBDC tissue samples from 80 cases. BT474 IBDC cell migration and invasion were quantified using the Transwell assay. Matrix metalloproteinase (MMP)-9 expression and activity were analyzed by RT-PCR, Western blotting and zymography. Activator protein (AP)-1 activity was measured with a luciferase reporter gene assay. The Wilcoxon signed-rank test, Chi-square test, the partition of Chi-square test, independent t-test, and Spearman's method were used for the statistical analysis. RESULTS: Phosphorylated ERK1/2 was detected in 58/80 (72.5%) IBDC tissues, and was associated with higher TNM stage and lymph node metastasis, but not patient age or tumor size. Individually, epidermal growth factor (EGF), and interleukin (IL)-1ß activated ERK1/2, increased cell migration and invasion, MMP-9 expression and activity, AP-1 activation in vitro and the expression of p-ERK1/2 was positively correlated with EGF expression levels, as well as IL-1ß, MMP-9 and c-fos in IBDC tissue samples. Co-stimulation with EGF and IL-1ß synergistically increased ERK1/2 and AP-1 activation, cell migration and invasion, and MMP-9 expression and activity. Inhibition of ERK1/2 using U0126 or siRNA abolished EGF and/or IL-1ß-induced cell migration and invasion in a dose-dependent manner. CONCLUSION: Activated ERK1/2 was associated with higher TNM stage and lymph node metastasis in IBDC. Both in vitro and in vivo studies indicated that ERK-1/2 activation may increase the metastatic ability of IBDC cells. Growth and inflammatory factors synergistically induced IBDC cell migration and invasion via ERK1/2 signaling, AP-1 activation and MMP-9 upregulation.


Assuntos
Carcinoma Ductal de Mama/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Interleucina-1beta/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Carcinoma Ductal de Mama/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Feminino , Humanos , Interleucina-1beta/farmacologia , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Fosforilação , Interferência de RNA , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo
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