Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
PeerJ Comput Sci ; 10: e1977, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660191

RESUMEN

Emotional recognition is a pivotal research domain in computer and cognitive science. Recent advancements have led to various emotion recognition methods, leveraging data from diverse sources like speech, facial expressions, electroencephalogram (EEG), electrocardiogram, and eye tracking (ET). This article introduces a novel emotion recognition framework, primarily targeting the analysis of users' psychological reactions and stimuli. It is important to note that the stimuli eliciting emotional responses are as critical as the responses themselves. Hence, our approach synergizes stimulus data with physical and physiological signals, pioneering a multimodal method for emotional cognition. Our proposed framework unites stimulus source data with physiological signals, aiming to enhance the accuracy and robustness of emotion recognition through data integration. We initiated an emotional cognition experiment to gather EEG and ET data alongside recording emotional responses. Building on this, we developed the Emotion-Multimodal Fusion Neural Network (E-MFNN), optimized for multimodal data fusion to process both stimulus and physiological data. We conducted extensive comparisons between our framework's outcomes and those from existing models, also assessing various algorithmic approaches within our framework. This comparison underscores our framework's efficacy in multimodal emotion recognition. The source code is publicly available at https://figshare.com/s/8833d837871c78542b29.

2.
Thyroid ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38243825

RESUMEN

Background: As an actin cytoskeleton interactor, PDZ (postsynaptic density 65-discs large-zonula occludens 1) and LIM (abnormal cell lineage 11-isket 1-mechanosensory abnormal 3) domain protein 7 (PDLIM7) was supposed to play an essential role modulating cytoskeleton. Focal adhesions (FAs), which are located at the cytomembrane terminus of actin cytoskeleton, function as a force sensor and can transform the mechanical signal to a biochemical signal. Focal adhesion kinase (FAK) localizes to and regulates signal transduction in FAs, which play an essential role in cell polarity, migration, and invasion. However, whether PDLIM7 is involved in FAs-associated signal transduction and its role in tumor invasion and metastasis remains largely unknown. Methods: A cohort of 80 patients with papillary thyroid carcinoma (PTC) at The Second Affiliated Hospital of Guilin Medical University, as well as 512 PTC samples from The Cancer Genome Atlas thyroid cancer database was utilized to analyze the expression of PDLIM7 and its association with prognosis. Survival data were assessed using Kaplan-Meier curves, whereas clinicopathological characteristics such as age, sex, tumor size, multilocality, extrathyroidal extension, lymph metastases, Hashimoto's thyroiditis, distant metastasis, and TNM stage were considered. Functional assays were performed in vitro and in a xenograft mouse model to assess the role of PDLIM7 in PTC cell lines. The colocalization of PDLIM7 with FAK and integrin alpha V (ITGAV) was determined using immunofluorescence assay and immunoprecipitation assay. Protein expression levels in cell and tissue biopsies were measured through Western blotting and immunohistochemistry. Results: (1) The PDLIM7 protein frequently upregulated in both PTC tissues and cells, and overexpression of PDLIM7 is associated with advanced clinicopathological characteristics. (2) Knockdown of PDLIM7 effectively inhibits cell proliferation, migration, and invasion in PTC cell lines in vitro. (3) Knockdown of PDLIM7 hinders the growth and metastasis of TPC-1 xenografts in vivo. (4) PDLIM7 demonstrates colocalization with both FAK and the FA molecule ITGAV and the knockdown of PDLIM7 resulted in disassembly of FAs and proteosome-dependent degradation of FAK in PTC cell lines. Conclusions: PDLIM7 function as an oncoprotein in PTC to promote metastasis, and a novel underlying mechanism is proposed that PDLIM7 keeps FAK protein from proteosome-dependent degradation.

3.
Phytother Res ; 37(7): 2979-2994, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36866539

RESUMEN

Aloe-emodin (AE) has been shown to inhibit the proliferation of several cancer cell lines, including human nasopharyngeal carcinoma (NPC) cell lines. In this study, we confirmed that AE inhibited malignant biological behaviors, including cell viability, abnormal proliferation, apoptosis, and migration of NPC cells. Western blotting analysis revealed that AE upregulated the expression of DUSP1, an endogenous inhibitor of multiple cancer-associated signaling pathways, resulting in blockage of the extracellular signal-regulated kinase (ERK)-1/2, protein kinase B (AKT), and p38-mitogen activated protein kinase(p38-MAPK) signaling pathways in NPC cell lines. Moreover, the selective inhibitor of DUSP1, BCI-hydrochloride, partially reversed the AE-induced cytotoxicity and blocked the aforementioned signaling pathways in NPC cells. In addition, the binding between AE and DUSP1 was predicted via molecular docking analysis using AutoDock-Vina software and further verified via a microscale thermophoresis assay. The binding amino acid residues were adjacent to the predicted ubiquitination site (Lys192) of DUSP1. Immunoprecipitation with the ubiquitin antibody, ubiquitinated DUSP1 was shown to be upregulated by AE. Our findings revealed that AE can stabilize DUSP1 by blocking its ubiquitin-proteasome-mediated degradation and proposed an underlying mechanism by which AE-upregulated DUSP1 may potentially target multiple pathways in NPC cells.


Asunto(s)
Aloe , Emodina , Neoplasias Nasofaríngeas , Humanos , Emodina/farmacología , Carcinoma Nasofaríngeo , Ubiquitina , Simulación del Acoplamiento Molecular , Transducción de Señal , Apoptosis , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular , Fosfatasa 1 de Especificidad Dual/metabolismo
4.
Micromachines (Basel) ; 13(12)2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36557338

RESUMEN

Random lasers (RLs) are a kind of coherent light source with optical feedback based on disorder-induced multiple scattering effects instead of a specific cavity. The unique feedback mechanism makes RLs different from conventional lasers. They have the advantages of small volume, flexible shape, omnidirectional emission, etc., and have broad application prospects in the fields of laser illumination, speckle-free imaging, display, and sensing. Colloidal metal-halide perovskite nanomaterials are a hot research field in light sources. They have been considered as desired gain media owing to their superior properties, such as high photoluminescence, tunable emission wavelengths, and easy fabrication processes. In this review, we summarize the research progress of RLs based on perovskite nanomaterials. We first present the evolution of the RLs based on the perovskite quantum dots (QDs) and perovskite films. The fabrication process of perovskite nano-/microstructures and lasers is discussed in detail. After that, the frontier applications of perovskite RLs are discussed. Finally, the challenges are discussed, and the prospects for further development are proposed.

5.
Nanomaterials (Basel) ; 12(20)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36296864

RESUMEN

Laser printing has become a promising alternative for large-scale fabrication of functional devices. Here, laser-induced forward transfer (LIFT) of nanosilica was successfully achieved using a lower-cost nanosecond laser with a center wavelength of 1064 nm. To enhance the light absorption of silica, a small amount of graphene oxide (GO) was added to the fumed silica. Investigations were conducted to give an insight into the role of GO in the LIFT process. Pattern deposition was achieved with a minimum line width of 221 µm. The scattering can be tuned from ~2.5% to ~17.5% by changing the laser fluence. The patternable transparent display based on laser transferred nanosilica (LTNS) film was also demonstrated, showing its capability to deliver information on multiple levels. This LIFT based technique promotes fast, flexible, and low-cost manufacturing of scattering-based translucent screens or patterns for transparent displays.

6.
Endokrynol Pol ; 73(6): 942-946, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35971926

RESUMEN

Streptozotocin (STZ)-induced diabetes rodent models are widely used to study the pathogenesis and metabolic function in diabetes (DM). The aim of this study was to assess the antioxidant effect of curcumin in STZ-induced type 2 diabetes mellitus (T2DM). In this research, rats were randomly divided into 3 groups (8 in each group): a nondiabetic group (Control), a diabetic group (DM), and a curcumin treatment group (DM + Cur 200 mg/kg group). Meanwhile, after intraperitoneal injection (i.p.), associated-oxidative stress parameters were observed, malondialdehyde (MDA) was decreased, and glutathione peroxidase (GPX) and super oxide dismutase (SOD) were restored in pancreatic tissues of curcumin-treated DM rats. In addition, curcumin improved the survival and function of islet cells with decreased cell apoptosis in Langerhans islet and increased insulin secretion in the STZ-induced T2DM rat model. Our findings suggest that curcumin is a potent candidate for the prevention and therapy of DM.


Asunto(s)
Curcumina , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Islotes Pancreáticos , Ratas , Animales , Antioxidantes/efectos adversos , Curcumina/efectos adversos , Diabetes Mellitus Tipo 2/metabolismo , Estreptozocina/efectos adversos , Ratas Wistar , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/patología , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Glucemia/metabolismo
7.
J Cell Mol Med ; 24(11): 6438-6447, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32307891

RESUMEN

Cisplatin resistance is one of the main obstacles in the treatment of advanced nasopharyngeal carcinoma (NPC). AKR1C1 is a member of the Aldo-keto reductase superfamily (AKRs), which converts aldehydes and ketones to their corresponding alcohols and has been reported to be involved in chemotherapeutic resistance of multiple drugs. The expression and function of AKR1C1 in NPC have not been reported until now. The aim of this research was to investigate the expression of AKR1C1 and it is role in cisplatin resistance in NPC. AKR1C1 protein expression was detected by immunohistochemistry in human NPC tissues and by Western blot assays in NPC and immortalized nasopharyngeal epithelial cells. The effects of AKR1C1 knock-down by siRNA on proliferation, migration and invasion in NPC cells were evaluated by CCK8, wound healing and transwell assays. To evaluate the effects of AKR1C1 silencing on cisplatin sensitivity in NPC cells, CCK8 assays were used to detect cell proliferation, flow cytometry was used to detect cell cycle distribution, and flow cytometry and DAPI staining were used to detect cell apoptosis. AKR1C1 down-regulation was associated with advanced clinicopathological characters such as larger tumor size, more lymphatic nodes involvement, with metastasis and later clinical stages, while AKR1C1 down-regulation was a good prognostic factor for overall survival (OS) in NPC patients. In vitro study showed that AKR1C1 was not directly involved in the malignant biological behaviours such as proliferation, cell cycle progression and migration of NPC cells, whereas AKR1C1 knock-down could enhance cisplatin sensitivity of NPC cells. These results suggest that AKR1C1 is a potential marker for predicting cisplatin response and could serve as a molecular target to increase cisplatin sensitivity in NPC.


Asunto(s)
20-Hidroxiesteroide Deshidrogenasas/metabolismo , Cisplatino/uso terapéutico , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/patología , Pronóstico
8.
ACS Appl Mater Interfaces ; 10(30): 25717-25725, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30036033

RESUMEN

Human health and industrial instruments have been suffering from bacterial colonization on the surface of materials for a long time. Recently, antibacterial coatings are regarded as the new strategy to resist bacterial pathogens. In this work, novel highly transparent and superhydrophobic coatings with extremely low bacterial adhesion and bactericidal performance were prepared by spray-coating hydrophobic silica sol and CuO nanoparticles. The coated glass showed high transmittance in 300-2500 nm with a maximum value of 96.6%. Compared with bare glass, its superhydrophobic characteristics resulted in a reduction in adhesion of bacteria ( Escherichia coli, E. coli) by up to 3.2 log cells/cm2. Additionally, the live/dead staining test indicated that the as-prepared coating exhibited excellent bactericidal performance against E. coli. Moreover, the as-prepared coating could maintain their superhydrophobicity after the sand impact test. The proposed method to fabricate such coatings could be applied on various substrates. Therefore, this novel hybrid surface with the abilities to reduce bacterial adhesion and kill attached bacteria make it a promising candidate for biosensors, microfluidics, bio-optical devices, household facilities, lab-on-chips, and touchscreen devices.


Asunto(s)
Nanopartículas , Adhesión Bacteriana , Cobre , Escherichia coli , Dióxido de Silicio , Propiedades de Superficie
9.
J Nanosci Nanotechnol ; 16(1): 783-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27398523

RESUMEN

Copper oxides (CuO) with hierarchical structures have been synthesized via a solution-based route with the assistance of sodium dodecyl sulfate (SDS). The size and morphology of obtained products could be rationally tuned through altering the molar ratio of starting materials. The composition of mixed solvent and the aging time were also found to influence the shape evolution of CuO particles. Based on the analyses of X-ray diffraction, scanning electron microscopy and transmission electron microscopy etc., a plausible mechanism was proposed for the formation of CuO hierarchical structures. UV-visible absorption study demonstrates their potential applications in optical electronic devices, and catalytic oxidation of formaldehyde shows their potential applications in catalytic degradation of volatile organic compounds.

10.
J Chromatogr A ; 1431: 197-204, 2016 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-26774120

RESUMEN

A high throughput and low cost approach to separate free fatty acids (FFAs) from phospholipid and acylglycerols (esterified fatty acids, EFAs) has been demonstrated, which may be widely used as a sample preparation method in the metabolomics and lipid research. The optimal conditions for FFAs reacting with N-hydroxysuccinimide (NHS) only need 10min at room temperature to obtain a 93.5% yield of FFAs-NHS ester. The rest 6% FFA transformed into N-cyclohexyl-fatty acid-amide which is stable to methyl esterification adopted for fatty acids analysis. 10min are taken for FFAs-NHS ester to react with amino functionalized silica nanoparticles to immobilize the FFAs. The separation of FFAs from EFAs could be carried out readily by centrifugation. The whole process including derivatization, immobilization, and centrifugation takes less than 40min. Much more accurate fatty acids composition of rat plasma EFAs could be obtained by this approach than the previous reported methods.


Asunto(s)
Análisis Químico de la Sangre/métodos , Ácidos Grasos no Esterificados/aislamiento & purificación , Ácidos Grasos/aislamiento & purificación , Dióxido de Silicio/química , Animales , Ésteres/química , Ácidos Grasos/química , Ácidos Grasos no Esterificados/química , Glicéridos/química , Fosfolípidos/química , Ratas , Succinimidas/química
11.
Analyst ; 138(6): 1758-63, 2013 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-23361034

RESUMEN

In this work, nanostructured copper oxide of varied morphologies and high surface area were prepared by calcination of copper oxalate precursors, and were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis and differential thermal analysis, and nitrogen adsorption-desorption measurements. The sphere-like CuO (specific surface area: 73 m(2) g(-1)) functionalized QCM resonators were fabricated and explored for HCN sensing. The sensitivity (10 s HCN exposure) of sphere-like CuO functionalized QCM resonators reached as high as 6.53 Hz µg(-1). The reproducibility and stability of sphere-like CuO functionalized QCM resonators was excellent, and the selectivity was very high with a converse response to examined common chemicals. The high surface area CuO functionalized QCM sensors may be applicable for HCN gas sensing.

12.
J Colloid Interface Sci ; 368(1): 41-8, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22024372

RESUMEN

The present article reviews recent works in our laboratory about the sensing properties to toxic gases using nanostructured WO(3), TiO(2), FTiO(2), and CuO functionalized quartz crystal microbalance (QCM) sensors. WO(3) and TiO(2) functionalized QCM sensors have much shorter response time than those functionalized by conventional hydrogen-bond acidic branched copolymers for detection of dimethyl methylphosphonate (DMMP). FTiO(2) functionalized QCM sensors can improve the gas sensing characteristics by shortening the response time but at the price of partial irreversibility. The sensing mechanism was examined by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Varied CuO nanostructures were synthesized by simple modulation of reaction conditions. All the as-prepared CuO was applied on QCM resonators and explored for HCN sensing. Surprisingly, responses of all the sensors to HCN were found to be in an opposite direction as compared with other common volatile substances, offering excellent selectivity for HCN detection. The sensitivity was very high, and the response and recovery were very fast. Comparison of the specific surface areas of CuO nanostructures showed that CuO of higher surface area is more sensitive than that of lower surface area, indicating that the specific surface area of these CuO nanostructures plays an important role in the sensitivity of related sensors. Based on experimental results, a sensing mechanism was proposed in which a surface redox reaction occurs between CuO and Cu(2)O on the CuO nanostructures reversibly upon contact with HCN and air, respectively. The CuO functionalized QCM sensors are considered to be a promising candidate for trace HCN gas detection in practical applications.

13.
Environ Sci Technol ; 45(14): 6088-94, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21699255

RESUMEN

In this work, quartz crystal microbalance (QCM) sensors for detection of trace hydrogen cyanide (HCN) gas were developed based on nanostructural (flower-like, boat-like, ellipsoid-like, plate-like) CuO. Responses of all the sensors to HCN were found to be in an opposite direction as compared with other common volatile substances, offering excellent selectivity for HCN detection. The sensitivity of these sensors is dependent on the morphology of CuO nanostructures, among which the plate-like CuO has the highest sensitivity (2.26 Hz/µg). Comparison of the specific surface areas of CuO nanostructures shows that CuO of higher surface area (9.3 m(2)/g) is more sensitive than that of lower surface area (1.5 m(2)/g), indicating that the specific surface area of these CuO nanostructures plays an important role in the sensitivity of related sensors. On the basis of experimental results, a sensing mechanism was proposed in which a surface redox reaction occurs between CuO and Cu(2)O on the CuO nanostructures reversibly upon contact with HCN and air, respectively. The CuO-functionalized QCM sensors are considered to be a promising candidate for trace HCN gas detection in practical applications.


Asunto(s)
Contaminantes Atmosféricos/análisis , Cobre/química , Monitoreo del Ambiente/instrumentación , Cianuro de Hidrógeno/análisis , Nanoestructuras/química , Tecnicas de Microbalanza del Cristal de Cuarzo/instrumentación , Monitoreo del Ambiente/métodos , Espectrometría de Masas , Microscopía Electrónica de Transmisión , Tecnicas de Microbalanza del Cristal de Cuarzo/métodos , Difracción de Rayos X
14.
J Colloid Interface Sci ; 359(1): 68-74, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21507410

RESUMEN

Magnetic manganese oxide nanostructures are fabricated at room temperature by mixing a KMnO(4) solution and oleic acid capped Fe(3)O(4) particles. Oleic acid molecules capped Fe(3)O(4) particles are oxidized by potassium permanganate (KMnO(4)) in an aqueous solution to produce porous magnetic manganese oxide nanostructures. The synthesis technique can be extended to other MnO(x) structures with composition of different nanocrystals, such as quantum dots, noble metal crystals which may have important applications as catalysts, adsorbents, electrodes and advanced materials in many scientific disciplines. Transmission electron microscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and nitrogen adsorption-desorption measurements are employed to characterize the structures. As an adsorbent in water treatment, the nanostructures possess a large adsorption capability and high organic pollutant removal rates due to the large surface area and pore volume. The nanostructures are recyclable as their adsorption capability can be recovered by combustion. Furthermore, the strong magnetism exhibited by the structures provides an easy and efficient separation means in wastewater treatment under an external magnetic field.


Asunto(s)
Magnetismo , Compuestos de Manganeso/química , Compuestos de Manganeso/síntesis química , Nanoestructuras/química , Óxidos/química , Óxidos/síntesis química , Agua/química , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
15.
J Colloid Interface Sci ; 355(1): 15-22, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21186032

RESUMEN

In this work, flower-like, boat-like, plate-like and ellipsoid-like copper oxide (CuO) nanostructures were fabricated by simple modulation of reaction conditions. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, nitrogen adsorption-desorption measurements and UV-visible diffuse reflectance spectra were employed to characterize the obtained CuO nanostructures. Reactants, hydrothermal temperature and time were found to largely affect the morphology and structure of CuO nanostructures. Flower-like and boat-like CuO nanostructures were successively fabricated by increasing hydrothermal time. Plate-like and ellipsoid-like CuO nanostructures were produced by modulating the use of polyethylene glycol (PEG) and NH(3)·H(2)O. The formation mechanisms were proposed based on the experimental results, which show that both PEG and NH(3)·H(2)O play an important role in the formation of the morphology and structure of CuO. The catalytic activity of the as-prepared CuO nanostructures was demonstrated by catalytic oxidation of methylene blue (MB) in presence of hydrogen peroxide (H(2)O(2)). The as-prepared CuO nanostructures all show good catalytic activity.

16.
Anal Chim Acta ; 659(1-2): 266-73, 2010 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-20103134

RESUMEN

In this work, peculiar porous alpha-Fe(2)O(3) nanospheres were fabricated by a glycine-assisted hydrothermal method. They have large mesopores (ca. 10nm) in the core and small mesopores (<4 nm) in the shell. To our best knowledge, there have been so far no reports on the synthesis of such peculiar porous alpha-Fe(2)O(3) nanospheres. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy and transmission electron microscopy were employed to characterize the obtained Fe(2)O(3) nanospheres. Effects of preparation conditions, such as reactants, reaction temperature and reaction duration, were investigated on the morphology and structure of Fe(2)O(3) nanospheres. It was shown that the morphology and structure could be readily controlled by the time and temperature of hydrothermal treatment. The formation mechanism was proposed based on experimental results, which shows that glycine molecules play an important role in the formation of the morphology and porous structure of alpha-Fe(2)O(3). The alpha-Fe(2)O(3) porous nanospheres were used as gas sensing layer, and exhibited excellent gas-sensing properties to ethanol in terms of response and selectivity. The sensors showed good reproducibility and stability as well as short response (9 s) and recovery time (43 s) even at an ethanol concentration as low as 50 ppm. The gas-sensing properties of porous alpha-Fe(2)O(3) nanospheres are also significantly better than those of previously reported Fe(2)O(3) nanoparticles (ca. 30 nm). The sensitivity of the former is over four times higher than that of the latter at varied ethanol concentrations. The gas-sensing mechanism was discussed in details. Both fast response and steady signal make these peculiar nanostructures a promising candidate for ethanol detection.


Asunto(s)
Técnicas Electroquímicas/métodos , Compuestos Férricos/química , Gases/análisis , Glicina/química , Nanopartículas del Metal/química , Electrodos , Etanol/análisis , Gases/química , Nanopartículas del Metal/ultraestructura , Porosidad , Temperatura
17.
Anal Chim Acta ; 654(2): 120-6, 2009 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-19854342

RESUMEN

Tungsten oxide (WO(3)) nanoflakes were synthesized, and characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. Thermogravimetry and X-ray photoelectron spectroscopy demonstrate the existence of strongly bound surface water molecules on the surface of tungsten oxide nanoflakes. WO(3) nanoflake functionalized quartz crystal microbalance sensors were fabricated, and firstly used for detection of trace sarin simulant, dimethyl methylphosphonate (DMMP). The sensors have better reproducibility and stability as well as much shorter response (30s) and recovery time (73s) than those functionalized by conventional hydrogen-bond acidic branched copolymers. The strongly bound surface water molecules on the surface of WO(3) nanoflakes are believed to play a key role in achieving such excellent DMMP sensing characteristics.

18.
Ai Zheng ; 23(6): 619-25, 2004 Jun.
Artículo en Chino | MEDLINE | ID: mdl-15191658

RESUMEN

BACKGROUND & OBJECTIVE: RNA interference (RNAi) is a new gene blocking technology that silences target gene at post-transcription level induced by the small interference RNA (siRNA). RNAi has been demonstrated great prospect in gene functional research and gene therapy areas. Nowadays, RNAi has been reported to be used to inhibit the expression of endogenous genes including cyclophilin, GAPDH, p53, and c-myc; and there were some progresses in the therapy of the diseases caused by AIDS and hepatitis viruses with RNAi. However, hTERT gene, which was highly expressed in hepatocellular carcinoma and other malignant neoplasm, has not been researched by RNAi. In present research, we utilized RNAi to inhibit hTERT gene expression in vitro and in vivo, investigated the feasibility and specificity of gene therapy for hepatocellular carcinoma. METHODS: Small interference RNAs homologous to hTERT gene were designed,pTZU6+1-shRNA-hTERT vector was constructed and transfected into hepatocellular carcinoma SMMC-7721 cells and transplanted SMMC-7721 tumor in nude mice to induce RNAi. The changes of hTERT gene expression and tumor cell proliferation in both siRNA treatment groups and control group were determined by flow cytometry, reverse transcription polymerase chain reaction (RT-PCR), immunochemistry in vitro and in vivo. RESULTS: The expression of hTERT had been obviously inhibited by RNAi in vitro. The inhibition rate of cell growth was 37.5% after pTZU6+1-shRNA-hTERT vector was transfected to hepatocellular carcinoma SMMC-7721 cells; the phase of cell cycle indicated the reduction of S phase, while G(1)/G(0) phase increased. The mRNA level of hTERT decreased from 99.4% to 53.1%, its protein expression reduced from 86.3% to 46.6%. The tumor size reduced after treated with pTZU6+1-shRNA-hTERT vector in vivo; hTERT mRNA level decreased from 99.1% to 76.2%, and its protein expression decreased from 87.2% to 61.8% in siRNA treatment group. In contrast, there were no changes in control groups in vitro and in vivo. CONCLUSION: RNAi inhibits the hTERT gene expression and proliferation of hepatocellular carcinoma SMMC-7721 cells with specificity, and is a possible new approach for neoplasm gene therapy.


Asunto(s)
Terapia Genética , Neoplasias Hepáticas/terapia , Interferencia de ARN , ARN Interferente Pequeño/farmacología , Telomerasa/genética , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , División Celular/efectos de los fármacos , Línea Celular Tumoral , Proteínas de Unión al ADN , Vectores Genéticos , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Mensajero/genética , ARN Interferente Pequeño/genética , Telomerasa/biosíntesis , Transfección
19.
Zhonghua Gan Zang Bing Za Zhi ; 11(7): 412-4, 2003 Jul.
Artículo en Chino | MEDLINE | ID: mdl-12890343

RESUMEN

OBJECTIVES: To study on the relationship between platelet Ca2+(i), CD62P, CD63, serum CD62P (SCD62P) and cirrhosis patients. METHODS: Platelet CD62P, CD63 were determined with flow cytometry, SCD63P with ELISA, and Ca2+(i) in platelet was determined with fluorophotometry. RESULTS: Platelet Ca2+(i), CD62P, CD63, and SCD62P levels in cirrhosis patients were (103.1+/-22.2)nmol/L, (47.6+/-20.0)%, (47.1+/-24.6)%, and (67.6+/-37.6)microg/L, and in controls were (57.6+/-13.1)nmol/L, (3.1+/-0.7)%, (2.5+/-0.7)%, and (24.0+/-6.5)microg/L, respectively. The levels in the former were higher than those in the latter (t > or = 6.148, P<0.05). The above levels in upper gastrointestinal haemorrhage group were much higher than those in the non-haemorrhage group (120.3nmol/L+/-18.8nmol/L vs 91.1nmol/L+/-14.3nmol/L, 64.9%+/-14.7% vs 34.6%+/- 11.9%, 70.9%+/-14.5% vs 30.2%+/-14.4%, and 103.6microg/L+/-14.9microg/L vs 40.8microg/L+/-24.0microg/L, respectively, t > or = 5.380, P<0.05). But the numbers of platelet between the two groups were no obvious difference. CONCLUSIONS: Platelet in the cirrhosis patients is greatly active, and the detection of platelet CD62P, CD63, SCD62P has a certain value in judging the degree of cirrhosis.


Asunto(s)
Antígenos CD/sangre , Plaquetas/química , Calcio/sangre , Cirrosis Hepática/sangre , Selectina-P/sangre , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Glicoproteínas de Membrana Plaquetaria , Tetraspanina 30
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...