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1.
Cancer Sci ; 112(5): 1888-1898, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33560542

RESUMEN

Circular RNAs (circRNAs) have been identified to exert vital biological functions and can be used as new biomarkers in a number of tumors. However, little is known about the functions of circRNAs in myelodysplastic syndrome (MDS). Here, we aimed to investigate circRNA expression profiles and to investigate the functional and clinical value of circRNAs in MDS. Differential expression of circRNAs between MDS and control subjects was analyzed using circRNA arrays, in which we identified 145 upregulated circRNAs and 224 downregulated circRNAs. Validated by real-time quantitative PCR between 100 MDS patients and 20 controls, three upregulated (hsa_circRNA_100352, hsa_circRNA_104056, and hsa_circRNA_104634) and three downregulated (hsa_circRNA_103846, hsa_circRNA_102817, and hsa_circRNA_102526) circRNAs matched the arrays. The receiver operating characteristic curve analysis of these circRNAs showed that the area under the curve was 0.7266, 0.8676, 0.7349, 0.7091, 0.8806, and 0.7472, respectively. Kaplan-Meier survival analysis showed that only hsa_circRNA_100352, hsa_circRNA_104056, and hsa_circRNA_102817 were significantly associated with overall survival. Furthermore, we generated a competing endogenous RNA network focused on hsa_circRNA_100352, hsa_circRNA_104056, and hsa_circRNA_102817. Analyses using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes showed that the three circRNAs were linked with some important cancer-related functions and pathways.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Síndromes Mielodisplásicos/metabolismo , ARN Circular/metabolismo , Anciano , Anemia Refractaria/genética , Anemia Refractaria/metabolismo , Anemia Refractaria con Exceso de Blastos/genética , Anemia Refractaria con Exceso de Blastos/metabolismo , Anemia Sideroblástica/genética , Anemia Sideroblástica/metabolismo , Área Bajo la Curva , Biomarcadores de Tumor/genética , Médula Ósea/metabolismo , Estudios de Casos y Controles , Regulación hacia Abajo , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/sangre , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/mortalidad , ARN Circular/genética , Curva ROC , Reacción en Cadena en Tiempo Real de la Polimerasa , Estadísticas no Paramétricas , Regulación hacia Arriba
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1253-7, 2015 May.
Artículo en Chino | MEDLINE | ID: mdl-26415438

RESUMEN

Wood electromagnetic shielding material, which was made by treating wood with electroless plating, not only keep the superior characteristics of wood, but also improve the conductivity, thermal conductivity and electromagnetic shielding properties of wood. The emergence of this material opens the way to the value-added exploitation of wood and widens the processing and application field for the electromagnetic shielding material. In order to explore the feasibility of using NIR technology to investigate the properties of wood electromagnetic shielding material, this study analysis the samples before and after copper plated process by the NIR spectroscopy coupled with principal component analysis (PCA). The results showed that (1) there exist significant differences between samples before and after copper plated process both on the spectral shape and absorption, and the great differences can also be seen in the samples with different treat time, especially for the samples with 5 min treat time; (2) after PCA analysis, six clusters from the samples before and after copper plated process were separately distributed in the score plot, and the properties of untreated wood and sensitized wood were similar, and the properties of samples for 25 and 40 min treat time were also similar in order that these samples were close to each other, all of which might suggest that the NIR spectroscopy reflected major feature information about material treatment; (3) After comparing the PCA performance between NIR and visible spectral region, it could be found that the classification performance of samples before and after copper plated process based on the NIR region were better than that based on the visible region, and the information of color on the surface of samples were preferably reflected in the visible region, which could indicate that there are more information about samples' surface characters using the visible spectroscopy coupled with NIR spectroscopy and it is feasible to use visible-NIR technology to investigate the surface characteristics of natural polymers treated with electroless copper plating.


Asunto(s)
Cobre , Espectroscopía Infrarroja Corta , Madera , Análisis de Componente Principal
3.
Carbohydr Polym ; 91(1): 224-8, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-23044126

RESUMEN

The preparation of primary fibers were performed from liquefied wood in phenol by melt-spinning with different spinnerettes of length/diameter ratio (L/D) (0, 2, and 4), to investigate the effect of the size of spinnerette on the thermal stability and structural properties of primary fibers. High thermal transition temperatures and small weight loss percentages of resultant primary fibers representing good thermal stability were obtained with L/D of spinnerette increasing. Besides, few defective structure occurred on cross section and surface of primary fibers in comparison with those prepared with spinnerette of L/D=0. We found that these improvements were caused by the formation of hydrogen bond among phenolic hydroxyl groups in the period of flow entering the cylindrical die of spinnerette. Thus, the precursor, with either porous structure for preparing activated carbon fibers or defect-free structure for preparing carbon fibers with high performance, can be probably prepared by controlling the spinnerette system.


Asunto(s)
Carbono/química , Madera/química , Fibra de Carbono , Fenol/química , Porosidad , Temperatura
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(6): 1674-7, 2010 Jun.
Artículo en Chino | MEDLINE | ID: mdl-20707174

RESUMEN

In order to make clear the changes in the micro crystal structures of celluloses and the functional group of main components including cellulose, hemicelluloses and lignin in wood decayed by fungi, the crystallinity, layer spacing d in crystalline unit cell, width of crystallite and functional group of main components of Populus tomentosa Carr wood, which was decayed by Phanerochaete Chysosporium (white-rot) and Postia Placenta (brown-rot) with various durations, for two weeks, four weeks, six weeks, eight weeks and ten weeks, respectively, were investigated by means of X-ray diffraction and FTIR spectroscopy methods. It was concluded that the lattice structures of crystallite in wood cellulose were not destroyed by PC and PP, and the two theta angles and layer spacing d in crystallite were constant, although the decaying treatment times were different for each other when decayed by the same fungi. However, the crystallinity and width of crystallite decreased with the decaying treatment times increasing, and the decaying effects by PP were more significantly than those by PC, which showed that the damage extent of celluloses decayed by PP was greater than that by PC. It was estimated that the xylan in hemicelluloses had been degraded to various extents with the process of decaying in wood, resulting in the carbonyl content increasing, and the effects of degradation on hemicelluloses and celluloses by PC and PP were almost the same. Furthermore, benzene rings in lignin, which had no remarkable changes by PP, were oxidized into chain hydrocarbon after decaying by PC.


Asunto(s)
Hongos , Espectroscopía Infrarroja por Transformada de Fourier , Madera/análisis , Difracción de Rayos X , Celulosa/química , Lignina/química , Polisacáridos/química , Populus/química
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 630-4, 2010 Mar.
Artículo en Chino | MEDLINE | ID: mdl-20496675

RESUMEN

In the present paper, the functional groups of PES/micro-nano cellulose composite membrane materials were characterized by Fourier transform infrared spectroscopy (FTIR). Also, changes in crystallinity in composite membrane materials were analyzed using X-ray diffraction (XRD). The effects of micro-nano cellulose content on hydrophilic property of composite membrane material were studied by measuring hydrophilic angle. The images of support layer structure of pure PES membrane material and composite membrane material were showed with scanning electron microscope (SEM). These results indicated that in the infrared spectrogram, the composite membrane material had characteristic peaks of both PES and micro-nano cellulose without appearance of other new characteristics peaks. It revealed that there were no new functional groups in the composite membrane material, and the level of molecular compatibility was achieved, which was based on the existence of inter-molecular hydrogen bond association between PES and micro-nano cellulose. Due to the existence of micro-nano cellulose, the crystallinity of composite membrane material was increased from 37.7% to 47.9%. The more the increase in micro-nano cellulose mass fraction, the better the van de Waal force and hydrogen bond force between composite membrane material and water were enhanced. The hydrophilic angle of composite membrane material was decreased from 55.8 degrees to 45.8 degrees and the surface energy was raised from 113.7 to 123.5 mN x m(-2). Consequently, the hydrophilic property of composite membrane material was improved. The number of pores in the support layer of composite membrane material was lager than that of pure PES membrane. Apparently, pores were more uniformly distributed.

6.
J Exp Bot ; 60(11): 3023-30, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19436045

RESUMEN

The mechanism for tree orientation in angiosperms is based on the production of high tensile stress on the upper side of the inclined axis. In many species, the stress level is strongly related to the presence of a peculiar layer, called the G-layer, in the fibre cell wall. The structure of the G-layer has recently been described as a hydrogel thanks to N(2) adsorption-desorption isotherms of supercritically dried samples showing a high mesoporosity (pores size from 2-50 nm). This led us to revisit the concept of the G-layer that had been, until now, only described from anatomical observation. Adsorption isotherms of both normal wood and tension wood have been measured on six tropical species. Measurements show that mesoporosity is high in tension wood with a typical thick G-layer while it is much less with a thinner G-layer, sometimes no more than normal wood. The mesoporosity of tension wood species without a G-layer is as low as in normal wood. Not depending on the amount of pores, the pore size distribution is always centred around 6-12 nm. These results suggest that, among species producing fibres with a G-layer, large structural differences of the G-layer exist between species.


Asunto(s)
Biofisica/métodos , Árboles/química , Fenómenos Biomecánicos , Porosidad , Estrés Mecánico , Árboles/anatomía & histología , Árboles/fisiología
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