Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
IEEE Trans Image Process ; 31: 99-109, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34793302

RESUMEN

Remote sensing scene classification (RSSC) is a hotspot and play very important role in the field of remote sensing image interpretation in recent years. With the recent development of the convolutional neural networks, a significant breakthrough has been made in the classification of remote sensing scenes. Many objects form complex and diverse scenes through spatial combination and association, which makes it difficult to classify remote sensing image scenes. The problem of insufficient differentiation of feature representations extracted by Convolutional Neural Networks (CNNs) still exists, which is mainly due to the characteristics of similarity for inter-class images and diversity for intra-class images. In this paper, we propose a remote sensing image scene classification method via Multi-Branch Local Attention Network (MBLANet), where Convolutional Local Attention Module (CLAM) is embedded into all down-sampling blocks and residual blocks of ResNet backbone. CLAM contains two submodules, Convolutional Channel Attention Module (CCAM) and Local Spatial Attention Module (LSAM). The two submodules are placed in parallel to obtain both channel and spatial attentions, which helps to emphasize the main target in the complex background and improve the ability of feature representation. Extensive experiments on three benchmark datasets show that our method is better than state-of-the-art methods.


Asunto(s)
Algoritmos , Tecnología de Sensores Remotos , Redes Neurales de la Computación
2.
Bioprocess Biosyst Eng ; 43(1): 21-31, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31542820

RESUMEN

tert-Butyl (3R,5S)-6-chloro-3,5-dihydroxyhexanoate [(3R,5S)-CDHH] is the key chiral intermediate to synthesize the side chain of the lipid-lowering drug rosuvastatin. Carbonyl reductases showed excellent activity for the biosynthesis of (3R,5S)-CDHH. The requirement of cofactor NADH/NADPH leads to high cost for the industrial application of carbonyl reductases. In this study, a self-sufficient biocatalyst based on carbonyl reductase and NADP+ co-immobilization strategy was developed on an amino resin carrier LX-1000HAA (SCR-NADP+@LX-1000HAA). The self-sufficient biocatalyst achieved in situ cofactor regeneration and showed the activity recovery of 77.93% and the specific activity of 70.45 U/g. Asymmetric synthesis of (3R,5S)-CDHH using SCR-NADP+@LX-1000HAA showed high enantioselectivity (> 99% e.e.) and yield (98.54%). Batch reactions were performed for ten cycles without extra addition of NADP+, and the total yield of (3R,5S)-CDHH achieved at 10.56 g/g biocatalyst. The present work demonstrated the potential of the self-sufficient biocatalyst for the asymmetric biosynthesis of rosuvastatin intermediate.


Asunto(s)
Oxidorreductasas de Alcohol/química , Biocatálisis , Candida/enzimología , Caproatos/síntesis química , Enzimas Inmovilizadas/química , Proteínas Fúngicas/química , NADP/química , Oxidorreductasas de Alcohol/genética , Candida/genética , Caproatos/química , Enzimas Inmovilizadas/genética , Proteínas Fúngicas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Rosuvastatina Cálcica/síntesis química , Rosuvastatina Cálcica/química
3.
Beilstein J Nanotechnol ; 10: 1434-1442, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31431855

RESUMEN

The prominent role of oxygen vacancies in the photocatalytic performance of bismuth tungsten oxides is well recognized, while the underlying formation mechanisms remain poorly understood. Here, we use the transmission electron microscopy to investigate the formation of oxygen vacancies and the structural evolution of Bi2WO6 under in situ electron irradiation. Our experimental results reveal that under 200 keV electron irradiation, the breaking of relatively weak Bi-O bonds leads to the formation of oxygen vacancies in Bi2WO6. With prolonged electron irradiation, the reduced Bi cations tend to form Bi clusters on the nanoflake surfaces, and the oxygen atoms are released from the nanoflakes, while the W-O networks reconstruct to form WO3. A possible mechanism that accounts for the observed processes of Bi cluster formation and oxygen release under energetic electron irradiation is also discussed.

4.
Drug Dev Res ; 80(4): 461-470, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30698296

RESUMEN

Isoliquiritigenin (ISL), a natural flavonoid isolated from plant licorice, has various pharmacological properties, including anticancer, anti-inflammatory, and antiviral effects. However, the underlying mechanisms and signaling pathways of ISL in human hepatocellular carcinoma (HCC) cells remain unknown. In this study, we evaluated the effects of ISL on the apoptosis of human HCC cells with a focus on reactive oxygen species (ROS) production. Our results showed that ISL exhibited cytotoxic effects on two human liver cancer cells in a dose-dependent manner. ISL significantly induced mitochondrial-related apoptosis and cell cycle arrest at the G2/M phase, which was accompanied by ROS accumulation in HepG2 cells. However, pretreatment with an ROS scavenger, N-acetyl-l-cysteine (NAC), inhibited ISL-induced apoptosis. In addition, ISL increased the phosphorylation levels of c-Jun N-terminal kinase (JNK), p38 kinase and inhibitor of NF-κB (IκB), and decreased the phosphorylation levels of extracellular signal-regulated kinase (ERK), signal transducer and activator of transcription 3 (STAT3), nuclear factor-kappa B (NF-κB), these effects were blocked by NAC and mitogen-activated protein kinase (MAPK) inhibitors. Taken together, the findings of this study indicate that ISL induced HepG2 cell apoptosis via ROS-mediated MAPK, STAT3, and NF-κB signaling pathways. Therefore, ISL may be a potential treatment for human HCC, as well as other cancer types.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Chalconas/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Células Hep G2 , Humanos , FN-kappa B/metabolismo , Factor de Transcripción STAT3/metabolismo
5.
Bioresour Technol ; 249: 161-167, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29040850

RESUMEN

tert-Butyl (3R,5S)-6-chloro-3,5-dihydroxyhexanoate ((3R,5S)-CDHH) is the key intermediate for synthesis of atorvastatin and rosuvastatin. Carbonyl reductase exhibits excellent activity toward tert-butyl (S)-6-chloro-5-hydroxy-3-oxohexanoate ((S)-CHOH) to synthesize (3R,5S)-CDHH. In this study, a whole cell biosynthesis reaction system to produce (3R,5S)-CDHH was constructed in organic solvents. A solution of 10% (v/v) Tween-80 was introduced to the reaction system as a co-solvent, which greatly enhanced biotransformation process, giving 98.9% yield, >99% ee and 1.8-fold higher space time yield in 5 h bioconversion of 1 M (S)-CHOH, compared with 98.7% yield and >99% ee in 9 h bioconversion of a purely aqueous reaction system. Moreover, a water-octanol biphasic reaction system was built and 20% of octanol was added as reservoir of substrate resulting in 98% yield, >99% ee and 4.08 mmol L-1 h-1 g-1 (wet cell weight) space time yield. This study paved a way for the whole cell biosynthesis of (3R,5S)-CDHH in mono and biphasic media.


Asunto(s)
Oxidorreductasas de Alcohol , Biotransformación , Estereoisomerismo
6.
ACS Appl Mater Interfaces ; 8(34): 22615-22, 2016 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-27509241

RESUMEN

We fabricated the nickel chains by a facile wet chemical method. The morphology of nickel chains were tailored by adjusting the amount of PVP during the synthesis process. Both the complex permittivity and permeability of the three-dimensional (3D) nets constructed by nickel chains present strong dependences on temperature in the frequency range of 8.2-12.4 GHz and temperature range of 323-573 K. The peaks in imaginary component of permittivity and permeability mainly derive from interfacial polarizations and resonances, devoting to dielectric and magnetic loss, respectively. The effect from both dielectric and magnetism contribute to enhancing the microwave absorption. The maximum absorption value of the 3D nickel chain nets is approximately -50 dB at 8.8 GHz and 373 K with a thickness of 1.8 mm, and the bandwidth less than -10 dB almost covers the whole investigated frequency band. These are encouraging findings, which provide the potential advantages of magnetic transition metal-based materials for microwave absorption application at elevated temperature.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3197-201, 2016 Oct.
Artículo en Chino | MEDLINE | ID: mdl-30222299

RESUMEN

Cu(InxGa1-x)Se2(CIGS) precursor films were prepared on ITO glass with potentiostatic electrodeposition. High quality CIGS films were obtained by selenization of the precursor films at high temperature in tubular furnace full of argon gas. X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Vis-NIR spectroscopy were used to characterize the structure, morphology, composition and Vis-NIR absorption of CIGS films, respectively. XRD results show the selenized CIGS films have a preferential orientation (112) with average crystallite of 24.7 nm. Raman spectroscopy reveals that the CIGS films are pure quaternaryphases with chalcopyrite structure, and without binary or ternary phases in the films. Vis-NIR measurements determine that the bandgap of CIGS increases with the increase of Ga concentration in the film. When the Ga concentration is 5.41%, its bandgap is about 1.11 eV, and the calculated ratio of Ga to (Ga+In) is 16.3%, which is less than the ratio of Ga to (Ga+In), 21.4%, measured by SEM. This indicates that crystallinity of CIGS filmsneeds to be further improved. All the measurements demonstratethat optimum ITO/CIGS has a promising application in bifacial solar cells. In this paper, we provide a newmethodtoelectrodeposit low cost CIGS precursor films and a new method forselenization ofthe precursor films at high temperature. As a result, theuniform and compact CIGS films with good adhesion on ITO are successfully fabricated by these methods. The above characterization show that we have obtained CIGS films with high crystallinity, near stoichiometry, few impurity phases and superior light absorption. Electrodeposition, like magnetron sputtering, is very suitable for large-scale industrial production. The research work in this paper is therefore important and considerable to massive production of electrodeposition of CIGS films.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3197-201, 2016 Oct.
Artículo en Chino | MEDLINE | ID: mdl-30246510

RESUMEN

Cu(InxGa1-x)Se2(CIGS) precursor films were prepared on ITO glass with potentiostatic electrodeposition. High quality CIGS films were obtained by selenization of the precursor films at high temperature in tubular furnace full of argon gas. X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Vis-NIR spectroscopy were used to characterize the structure, morphology, composition and Vis-NIR absorption of CIGS films, respectively. XRD results show the selenized CIGS films have a preferential orientation (112) with average crystallite of 24.7 nm. Raman spectroscopy reveals that the CIGS films are pure quaternaryphases with chalcopyrite structure, and without binary or ternary phases in the films. Vis-NIR measurements determine that the bandgap of CIGS increases with the increase of Ga concentration in the film. When the Ga concentration is 5.41%, its bandgap is about 1.11 eV, and the calculated ratio of Ga to (Ga+In) is 16.3%, which is less than the ratio of Ga to (Ga+In), 21.4%, measured by SEM. This indicates that crystallinity of CIGS filmsneeds to be further improved. All the measurements demonstratethat optimum ITO/CIGS has a promising application in bifacial solar cells. In this paper, we provide a newmethodtoelectrodeposit low cost CIGS precursor films and a new method forselenization ofthe precursor films at high temperature. As a result, theuniform and compact CIGS films with good adhesion on ITO are successfully fabricated by these methods. The above characterization show that we have obtained CIGS films with high crystallinity, near stoichiometry, few impurity phases and superior light absorption. Electrodeposition, like magnetron sputtering, is very suitable for large-scale industrial production. The research work in this paper is therefore important and considerable to massive production of electrodeposition of CIGS films.

9.
ACS Appl Mater Interfaces ; 7(34): 19408-15, 2015 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-26284741

RESUMEN

Ideal electromagnetic attenuation material should not only shield the electromagnetic interference but also need strong absorption. Lightweight microwave absorber with thermal stability and high efficiency is a highly sought-after goal of researchers. Tuning microwave absorption to meet the harsh requirements of thermal environments has been a great challenge. Here, grape-like Fe3O4-multiwalled carbon nanotubes (MWCNTs) are synthesized, which have unique multiscale-assembled morphology, relatively uniform size, good crystallinity, high magnetization, and favorable superparamagnetism. The Fe3O4-MWCNTs is proven to be a smart microwave-absorber prototype with tunable high intensities in double belts in the temperature range of 323-473 K and X band. Maximum absorption in two absorbing belts can be simultaneously tuned from ∼-10 to ∼-15 dB and from ∼-16 to ∼-25 dB by varying temperature, respectively. The belt for reflection loss ≤-20 dB can almost cover the X band at 323 K. The tunable microwave absorption is attributed to effective impedance matching, benefiting from abundant interfacial polarizations and increased magnetic loss resulting from the grape-like Fe3O4 nanocrystals. Temperature adjusts the impedance matching by changing both the dielectric and magnetic loss. The special assembly of MWCNTs and magnetic loss nanocrystals provides an effective pathway to realize excellent absorbers at elevated temperature.

10.
ACS Appl Mater Interfaces ; 7(13): 7073-7, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25806666

RESUMEN

We fabricated NiO nanorings on SiC, a novel hierarchical architecture, by a facile two-step method. The dielectric properties depend on temperature and frequency in the range from 373 to 773 K and X band. The imaginary part and loss tangent increase more than four times and three times with increasing temperature, respectively. The architecture demonstrates multirelaxation and possesses high-efficient absorption. The reflection loss exceeds -40 dB and the bandwidth covers 85% of X band (approximately -20 dB). The synergistic effect between multirelaxation and conductance is beneficial to the microwave absorption. Our findings provide a novel and feasible strategy to tune microwave absorption.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(10): 2863-7, 2014 Oct.
Artículo en Chino | MEDLINE | ID: mdl-25739239

RESUMEN

Based on sucrose solution as the research object, this paper measured the trans-reflective spectrum of sucrose solution of different concentration by the technique of near infrared spectrum in three optical path (4, 5, 6 mm). Five kinds of pretreatment method (vector normalization, baseline offset correction, multiplicative scatter correction, standard normal variate transformation, a derivative) were used to eliminate the influence of the optical path difference, and to establish model of the calibration set in combination with the PLS (Partial Least Squares)method. Five kinds of pretreatment method could restrain the inter ference of light path in varying degrees. Compared with the PLS model of original spectra, the model of multiple scattering correction combined with PLS method is the optimal model. The results of quantitative analysis of original spectra: the number of principal component PC= 6, the determination coefficient R2 = 0.891 278, the determination coefficient of cross validation R2CV = 0.888 374, root mean square error of calibration RMSEC = 1.704%, root mean square error of cross validation RMSECV = 1.827%; The results of quantitative analysis of spectra after MSC pretreatment: the number of principal component PC = 3, the determination coefficient R2 = 0.987 535, the determination coefficient of cross validation R2CV = 0.983 343, root mean square er- ror of calibration RMSEC = 0.89%, root mean square error of cross validation RMSECV = 1.05%. The correlation coefficient of the prediction set is as much as 0.976 22. root mean square error of prediction is 0.01, lesser than 0.014 36. The results show that the MSC can eliminate the influence of optical path difference, improve the prediction precision and improve the stability.

12.
PLoS One ; 7(7): e40316, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22792277

RESUMEN

BACKGROUND: Time discounting refers to the fact that the subjective value of a reward decreases as the delay until its occurrence increases. The present study investigated how time discounting has been affected in survivors of the magnitude-8.0 Wenchuan earthquake that occurred in China in 2008. METHODOLOGY: Nineteen earthquake survivors and 22 controls, all school teachers, participated in the study. Event-related brain potentials (ERPs) for time discounting tasks involving gains and losses were acquired in both the victims and controls. FINDINGS: The behavioral data replicated our previous findings that delayed gains were discounted more steeply after a disaster. ERP results revealed that the P200 and P300 amplitudes were increased in earthquake survivors. There was a significant group (earthquake vs. non-earthquake) × task (gain vs. loss) interaction for the N300 amplitude, with a marginally significantly reduced N300 for gain tasks in the experimental group, which may suggest a deficiency in inhibitory control for gains among victims. CONCLUSIONS: The results suggest that post-disaster decisions might involve more emotional (System 1) and less rational thinking (System 2) in terms of a dual-process model of decision making. The implications for post-disaster intervention and management are also discussed.


Asunto(s)
Desastres , Terremotos , Potenciales Relacionados con Evento P300 , Sobrevivientes/psicología , Adulto , Análisis de Varianza , Estudios de Casos y Controles , China , Toma de Decisiones/fisiología , Docentes , Femenino , Humanos , Masculino , Recompensa , Población Rural , Factores de Tiempo
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(4): 1094-7, 2012 Apr.
Artículo en Chino | MEDLINE | ID: mdl-22715792

RESUMEN

Thin films of cadmium sulfide (CdS) were prepared with ammonium chloride, cadmium chloride, potassium hydroxide and thiourea by chemical bath deposition (CBD). For comparison, CdS films were also deposited by radio frequency (RF) magnetron sputtering, using CdS and argon as a target and reactive gas, respectively. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet-visible spectroscopy. The results show that the CdS films prepared by the above two methods have (002) orientation, the CdS films deposited by RF magnetron sputtering are more compact and much smoother than those prepared by CBD, and have lager crystalline size of about 20-30 nm. The CdS films prepared by CBD have smaller crystalline size and more defects. The properties of CdS thin films prepared by RF magnetron sputtering are totally superior to those of CdS films by CBD, but the optical transmittance of CdS thin films at short wavelength is an exception. The energy gap of CdS films prepared by the two methods are all in the range of 2.3-2.5 eV.

14.
J Asian Nat Prod Res ; 14(8): 811-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22694138

RESUMEN

Five compounds were isolated from the root powder of Periploca sepium. By mainly HR-ESI-MS, (1)H, (13)C, and 2D NMR spectral data, they were characterized as periplocoside X (1), oligasaccharide A (2), periplocoside A (3), periplocoside E (4), and periplocoside N (5), respectively. Compounds 1-5 were found to possess insecticidal activities against the red imported fire ant. Among the compounds, periplocoside X showed significant activity with LD(50) values of 748.99, 116.62, 2169.58, and 3079.33mg/l against soldiers, workers, males, and alate females of red imported fire ant, respectively.


Asunto(s)
Hormigas/efectos de los fármacos , Insecticidas/aislamiento & purificación , Insecticidas/farmacología , Oligosacáridos/aislamiento & purificación , Oligosacáridos/farmacología , Periploca/química , Pregnenos/aislamiento & purificación , Pregnenos/farmacología , Animales , Femenino , Glicósidos , Insecticidas/química , Dosificación Letal Mediana , Masculino , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Oligosacáridos/química , Raíces de Plantas/química , Pregnenos/química
15.
Zhong Yao Cai ; 34(3): 452-5, 2011 Mar.
Artículo en Chino | MEDLINE | ID: mdl-21823466

RESUMEN

OBJECTIVE: To optimize the formulation of Danggui Liuhuang effervescent granules. METHODS: By means of quadratic regression rotation-orthogonal combination design, the effect of the proper proportion between citric acid and sodium bicarbonate, as well as the proper quantity of polyethylene glycol 6000 and sodium cyclamate on the dissolubility and pH of effervescent granules was studied. RESULTS: The best formulation was as follows: citric acid: sodium bicarbonate = 0.75: 1, the percentage of polyethylene glycol 6000 and cyclamate was 3.25% and 0.89%, respectively. CONCLUSION: The dissolubility and pH of the effervescent granules are better and the taste is satisfactory.


Asunto(s)
Ácido Cítrico/administración & dosificación , Medicamentos Herbarios Chinos/administración & dosificación , Bicarbonato de Sodio/administración & dosificación , Tecnología Farmacéutica , Análisis de Varianza , Química Farmacéutica , Ácido Cítrico/química , Ciclamatos/química , Combinación de Medicamentos , Medicamentos Herbarios Chinos/química , Excipientes/química , Tamaño de la Partícula , Plantas Medicinales/química , Polietilenglicoles/química , Control de Calidad , Bicarbonato de Sodio/química , Solubilidad
16.
Zhonghua Zhong Liu Za Zhi ; 33(3): 222-5, 2011 Mar.
Artículo en Chino | MEDLINE | ID: mdl-21575524

RESUMEN

OBJECTIVE: To explore the surgical treatment of hypopharyngeal and cervical esophageal cancers and the ways of reconstruction after hypopharyngo-oesphagectomy, and to evaluate their efficacy. METHODS: Twenty five patients with cancer of the laryngopharynx and cervical esophagus treated in our department between 1995 and 2007 were included in this study. Their clinical data were restrspectively analyzed. Among them, 17 cases had the tumor originated from the pyriform sinus, 3 of the posterior pharyngeal wall and 5 of the postcricoid region. Acording to the 2002 UICC criteria, all the tumors were stage T4, including 9 patients with cN0, 11 with cN1, and 5 with cN2 disease. The pharyngoesophageal defect reconstruction methods were as following: pharyngogastric anastomosis in 7 patients, free jejunal transplantion in 4, laryngotracheal flap in 8, and pectoralis major musculocutaneous flap in 6 patients. All patients were treated with modified and/or selective neck dissection. Among them, 8 cases received pre-operation radiotherapy, 17 received post-operative auxiliary radiotherapy. RESULTS: There was no operation death case in this group. All patients were followed up for 3 to 5 years. Three patients died in the first year. According to Kaplan-Meier analysis, the 1-year survival rate was 88.0%, 3-year survival rate was 48.0%, and 5-year survival rate was 28.0%. CONCLUSIONS: The use of primary repair of the defects of laryngopharynx and cervical esophagus expands the operative indication for cancers of the laryngopharynx and cervical esophagus, improves the survival rate and life quality of the patients. Regarding the repair method of choice, site of the tumor and size of the defect are the most important factors regarding choice of reconstruction method, while the patients' age and general condiction should also be considered to minimize the complications as more as possible.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias Hipofaríngeas/cirugía , Procedimientos de Cirugía Plástica/métodos , Anciano , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/secundario , Esofagectomía/métodos , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hipofaríngeas/patología , Neoplasias Hipofaríngeas/radioterapia , Hipofaringe/cirugía , Estimación de Kaplan-Meier , Neoplasias Pulmonares/secundario , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Faringectomía/métodos , Estudios Retrospectivos , Tasa de Supervivencia
17.
J Exp Clin Cancer Res ; 29: 140, 2010 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21040551

RESUMEN

BACKGROUND: HBO1 (histone acetyltransferase binding to ORC1) is a histone acetyltransferase (HAT) which could exert oncogenic function in breast cancer. However, the biological role and underlying mechanism of HBO1 in breast cancer remains largely unknown. In the current study, we aimed to investigate the role of HBO1 in breast cancer and uncover the underlying molecular mechanism. METHODS: Immunohistochemistry was applied to detect HBO1 protein expression in breast cancer specimens (n=112). The expression of protein level was scored by integral optical density (IOD) for further statistical analyses using SPSS. Real-time PCR was used to simultaneously measure mRNA levels of HBO1. The HBO1 protein expression in breast cancer cells was confirmed by western blot. RESULTS: HBO1 was highly expressed in breast cancer tissues and significantly correlated with estrogen receptor α (ERα) (p<0.001) and progestational hormone (PR) (p=0.002). HBO1 protein level also correlated positively with histology grade in ERα positive tumors (p=0.016) rather than ERα negative tumors. 17ß-estradiol (E2) could upregulate HBO1 gene expression which was significantly inhibited by ICI 182,780 or ERα RNAi. E2-increased HBO1 protein expression was significantly suppressed by treatment with inhibitor of MEK1/2 (U0126) in T47 D and MCF-7 cells. CONCLUSIONS: HBO1 was an important downstream molecule of ERα, and ERK1/2 signaling pathway may involved in the expression of HBO1 increased by E2.


Asunto(s)
Neoplasias de la Mama/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Regulación Neoplásica de la Expresión Génica , Histona Acetiltransferasas/biosíntesis , Western Blotting , Neoplasias de la Mama/genética , Línea Celular Tumoral , Estradiol/genética , Receptor alfa de Estrógeno/genética , Femenino , Expresión Génica , Histona Acetiltransferasas/genética , Humanos , Inmunohistoquímica , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/fisiología , Transfección
18.
J Phys Chem B ; 110(51): 25702-6, 2006 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-17181209

RESUMEN

A synthesis approach for shape control of single crystalline Bi nanostructures has been developed. By controlling the molar ratio of PVP and Bi in a polyol process, Bi nanocubes with an edge length of approximately 60-80 nm, triangular nanoplates with an edge length of 200-500 nm, and nanospheres with an average diameter of 75 nm have been successfully synthesized. In the same synthetic process, Bi nanobelts with lengths of up to 80 microm and widths of up to 0.6 microm were synthesized in large quantities by introducing a trace amount of Fe3+ species into the reaction system. These single crystalline nanostructure Bi materials are expected to find potential applications in a variety of areas including high efficiency thermoelectric devices.

19.
Zhong Yao Cai ; 29(10): 1087-90, 2006 Oct.
Artículo en Chino | MEDLINE | ID: mdl-17326411

RESUMEN

OBJECTIVE: To optimize preparative technique for banxia-houpu effervescent tablets. METHODS: Based on the pH, disintegration time limited, taste, and rigidity of effervescent tablets, the proper proportion between citric acid and sodium bicarbonate, as well as the proper quantity of polyethylene glycol 6000 and sodium cyclamate in the effervescent tablets were determined by using orthogonal design. The content of magnolol and honokiol in effervescent tablets were measured by HPLC. RESULTS: The optimal preparative technique was: cirtic acid: sodium bicarbonate = 0.65:1. The percentage of polyethylene glycol 6000 was 85%, and the percentage of sodium cyclamate was 1.0%. CONCLUSION: The preparative technique is stable, reliable and suitable for practical use.


Asunto(s)
Ácido Cítrico , Medicamentos Herbarios Chinos/química , Plantas Medicinales/química , Bicarbonato de Sodio , Tecnología Farmacéutica/métodos , Compuestos de Bifenilo/análisis , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Ácido Cítrico/administración & dosificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Concentración de Iones de Hidrógeno , Lignanos/análisis , Pinellia/química , Polietilenglicoles , Bicarbonato de Sodio/administración & dosificación , Comprimidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA