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1.
Inorg Chem ; 61(47): 18998-19009, 2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36378068

RESUMEN

By introducing Brønsted acidic ionic liquids (ILs), two dual-emitting lanthanide metal-organic complexes (Ln-MOCs) of {[Ln(imdc)(CH3OH)(H2O)3]Cl2}n (LnIMDC, Ln = Eu and Tb, imdc = 1,3-bis(carboxymethyl)imidazolium ion) were first prepared under solvothermal conditions. The crystal structures of LnIMDC were measured by single-crystal X-ray diffraction, and the crystal growth process of LnIMDC was carefully studied. It is found that the crystals are three-dimensional supramolecular structures built up by Ln-O coordination bonds and supramolecular forces. In the temperature range of 303-403 K, LnIMDC show good temperature-dependent emission properties with maximum relative thermal sensitivities of 3.29% K-1 at 375 K and 2.08% K-1 at 303 K for EuIMDC and TbIMDC, respectively. It is worth mentioning that both EuIMDC and TbIMDC exhibit good linear ratiometric emission-temperature response in temperature ranges of 353-403 and 323-373 K, respectively, which render EuIMDC and TbIMDC good ratiometric thermometers in high temperature range. Computational studies on the energy level of ILs [H2imdc]Cl and [imdc]- ion were performed, which validated the high energy transfer efficiency between the [imdc]- and Ln3+ ions and the unique solution concentration- and wavelength-dependent fluorescence properties of [H2imdc]Cl. The high fluorescence performance opens up new opportunities for practical applications of ILs in optical sensing.

2.
Mater Sci Eng C Mater Biol Appl ; 113: 110969, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32487387

RESUMEN

The rapid growth of the abalone industry has brought a great burden to the environment because of their inedible shells. Aiming at environmental and resource sustainability, porous microspheres of carbonate-substituted hydroxyapatite (HAP) were prepared by a hydrothermal method using abalone shells; then, they were further used as a carrier for doxorubicin (DOX) in a drug delivery system. The porous HAP microspheres were approximately 6 µm in size with a considerable specific surface area and average pore size (128.6659 cm2/g and 9.064 nm, respectively), which ensured excellent drug-handling capacity (95.542%). In addition, the pH responsiveness of the drug release system was favorable for effective in vivo drug release in an acidic tumor microenvironment. Moreover, the drug-loaded microspheres could effectively induce apoptosis of MCF-7 cells but were less cytotoxic to MC3T3-E1 cells. Because of its good biocompatibility, high drug loading capacity and controlled drug release property, the porous microspheres prepared in this experiment have potential application value in drug delivery and tumor therapy; furthermore, they make full use of abalone shells, providing environmental sustainability.


Asunto(s)
Antibióticos Antineoplásicos/química , Doxorrubicina/química , Portadores de Fármacos/química , Durapatita/química , Gastrópodos/metabolismo , Microesferas , Exoesqueleto/metabolismo , Animales , Antibióticos Antineoplásicos/metabolismo , Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/metabolismo , Doxorrubicina/farmacología , Liberación de Fármacos , Humanos , Ratones , Porosidad
3.
Mitochondrial DNA B Resour ; 5(1): 642-643, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33366683

RESUMEN

The bamboo aphid, Pseudoregma bambucicola, is a terrible insect pest of bamboos. Herein, the complete mitochondrial genome of a representative of this aphid from China was determined through next generation sequencing platform. The whole genome was 16,651 bp in size and encoded 13 protein-coding genes, 22 tRNA genes, and two rRNA genes. The phylogeny showed that two Chinese isolates of P. bambucicola clustered together and formed a monophyletic relationship with Hormaphis betulae in Hormaphidinae, supporting their species validity among the family Aphididae. The cumulative mitochondrial DNA data should contribute to a better understanding of the phylogenetic relationship of this aphid species.

4.
Mitochondrial DNA B Resour ; 5(1): 906-907, 2020 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33426278

RESUMEN

Hormaphis betulae (Hemiptera: Hormaphidinae) is a common aphid of birch plants. Here, the complete mitochondrial genome sequence of a representative of this aphid from China was determined using next generation sequencing platform. The genome was 15,129 bp in length and encoded 13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes. The phylogeny revealed that two Chinese isolates of H. betulae clustered together and formed a monophyletic relationship with Pseudoregma bambucicola in the subfamily Hormaphidinae, supporting their species validity in Aphididae. The cumulative mitochondrial DNA data provides a better understanding of the phylogenetic relationship of this species in plant aphids.

5.
Saudi J Biol Sci ; 26(5): 1032-1036, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31303837

RESUMEN

mtDNA COII gene sequences were identified and analyzed using different types of software, namely, MEGA5.0, DNAMAN, and DnaSP5.0 in four Chinese provinces, namely, Sichuan, Zhejiang, Guizhou and Shanghai. Analysis of molecular genetic variation and its genetic structure and differentiation, combined with NJ tree, MP tree analysis and analysis of molecular variance (AMOVA), at Fst = 0.0582 conclude that the genetic differentiation is low, gene flow is Nm = 8.0911, and gene exchange is sufficient. However, for the geographic populations of Pseudoregma bambucicola in the four provinces, their gene exchange is relatively weak at Nm = 0.8284, whereas the genetic differentiation is high at Fst = 0.3764. Based on the data, total nucleotide diversity between the populations is 0.00158 ±â€¯0.00021. The results showed that the total population of Tajima's D and Fu's Fs results are D = -0.885 and Fs = 0.226, respectively. The experimental numerical results showed that this total population is not significant (P > 0.10), indicating that nine different geographic populations are short-term. No expansion occurred in the internal population. This study provided a theoretical and practical basis for the comprehensive prevention and control of P. bambucicola.

6.
Mater Sci Eng C Mater Biol Appl ; 77: 708-712, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28532083

RESUMEN

Hydroxyapatite (HAP) has been widely used for repairing or substituting human hard tissues. In this paper, two typical ionic surfactants, cation hexadecyltrimethylammonium bromide (CTAB) and anion sodium dodecyl sulfate (SDS), were used for rapid conversion of HAP from abalone shell. From field emission scanning electron microscopy (FESEM), the prepared HAP is flake-like structure. From X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermal analysis, these samples contain a small amount of calcium carbonate whose content gradually increases by increasing the surfactants. The results showed that the HAP formed fast on the layer of abalone shell powder with the assistance of CTAB and SDS.


Asunto(s)
Nanoestructuras , Durapatita , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Tensoactivos , Difracción de Rayos X
7.
Mater Sci Eng C Mater Biol Appl ; 67: 182-187, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27287112

RESUMEN

Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53wt% the abalone water-soluble protein (AWSPro) and 2.04wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application.


Asunto(s)
Moluscos/química , Remineralización Dental/métodos , Diente/patología , Agua/química , Animales , Esmalte Dental/química , Esmalte Dental/ultraestructura , Humanos , Solubilidad , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
8.
Colloids Surf B Biointerfaces ; 142: 74-80, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26930036

RESUMEN

The application of hydroxyapatite (HAP) in different fields depends greatly on its morphology, composition and structure. Besides, the main inorganic building blocks of human bones and teeth are also HAP. Therefore, accurate shape and aggregation control and of hydroxyapatite particles will be of great interest. Herein, oriented bundles of flowerlike HAP nanorods were successfully prepared through hydrothermal treatment without acid-base regulation, with the mono-alkyl phosphate (MAP) and sodium citrate as surfactant and chelating agent, respectively. The prepared samples were characterized by the X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and zeta potential, the pH value and conductivity value of suspension were characterized by pH meter and conductivity measurement. The results showed that the MAP and citrate play an important role in assembly of HAP nanorods without acid-base regulation. Citrate calcium complex could decompose slowly and release citrate ions at hydrothermal conditions. Besides, the further decomposition of citrate ions could release aconitic acid as the reaction time prolongs. Moreover, the possible scheme for the formation process was discussed in detail.


Asunto(s)
Quelantes/química , Citratos/química , Durapatita/química , Tensoactivos/química , Adsorción , Compuestos de Calcio/química , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Transmisión , Nanotubos , Nitratos/química , Fosfatos/química , Citrato de Sodio , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
9.
Colloids Surf B Biointerfaces ; 134: 401-7, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26218713

RESUMEN

In this work, we encapsulated icariin (ICA) into chitosan (CS)/nano hydroxyapatite (nHAP) composite microspheres to form organic-inorganic hybrid microspheres for drug delivery carrier. The composition and morphology of composite microspheres were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and differential scanning calorimetry- thermogravimetric analysis (DSC-TGA). Moreover, we further studied the performance of swelling properties, degradation properties and drug release behavior of the microspheres. ICA, the extract of traditional Chinese medicine-epimedium, was combined to study drug release properties of the microspheres. ICA loaded microspheres take on a sustained release behavior, which can be not only ascribed to electrostatic interaction between reactive negative hydroxyl (OH) of ICA and positive amine groups (NH2) of CS, but also depended on the homogeneous dispersion of HAP nanoparticles inside CS organic matrix. In addition, the adhesion and morphology of osteoblasts were detected by inverted fluorescence microscopy. The biocompatibility of CS/nHAP/ICA microspheres was evaluated by the MTT cytotoxicity assay, Hoechst 33258 and PI fluorescence staining. These studies demonstrate that composite microspheres provide a suitable microenvironment for osteoblast attachment and proliferation. It can be speculated that the ICA loaded CS-based organic-inorganic hybrid microspheres might have potential applications in drug delivery systems.


Asunto(s)
Desarrollo Óseo , Quitosano/química , Durapatita/química , Microesferas , Nanopartículas , Rastreo Diferencial de Calorimetría , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
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