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1.
Luminescence ; 36(5): 1143-1150, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33675134

RESUMO

A series of Bi1-x Eux PO4 phosphors was successfully prepared using an easy citric acid- assisted hydrothermal method. The effects of synthesis temperature, amount of citric acid, and Eu3+ concentration on the crystal phase, morphology, and luminescence properties were investigated. X-ray diffraction results revealed that BiPO4 :Eu3+ formed a hexagonal phase at 80°C, although it transformed to a monoclinic phase when the hydrothermal temperature was increased to 160°C. Moreover, it was found that a small amount of Eu3+ doping and the addition of citric acid introduced no secondary or related phases. The morphologies of the samples varied from nanoparticles to spherical microparticles to polyhedrons after the synthesis temperature was adjusted. Particle size was controlled by adding different amounts of citric acid. Under 394 nm excitation, the Bi0.95 Eu0.05 PO4 phosphor prepared at 160°C with 0.3 g of citric acid had excellent luminescence properties. A possible crystal growth mechanism during this reaction is proposed.


Assuntos
Európio , Luminescência , Cristalização , Tamanho da Partícula , Difração de Raios X
3.
Int J Biol Macromol ; 146: 549-559, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31917983

RESUMO

We aimed to develop a stable nanosystem with k-carrageenan (Kc), an anionic polysaccharide, combined with tween 80 to stabilize zein nanoparticles. The experimental results showed that the particle size, zeta-potential, and stability of the system depend on the Kc amount when the zein amount was unchanged. We found that the nanosystem with 5.0 and 10.0 mg Kc had a smaller particle size (250.1 ± 0.9 and 287.6 ± 1.4 nm, respectively), low polydispersity index (PDI, ≤ 0.20), and high stability when the external conditions changed. No obvious flocculation or deposition was observed at pH of 3-9, salt ion concentrations of 0-500 mmol/L, temperature of 30 °C and 50 °C-90 °C, and storage at 4 °C for 30 days. When the Kc-ZNP system was loaded with curcumin (Cur), there was a good encapsulation effect (5.0 mg Kc with 1.00 mg Cur (EE (%) = 34.69% ± 2.02%, size = 380.23 ± 5.80 nm, PDI = 0.252 ± 0.018) and 10.0 mg Kc with 2.00 mg Cur (EE (%) = 20.13% ± 1.05%, size = 431.27 ± 0.78 nm, PDI = 0.269 ± 0.020), ensuring that the particle size was not too large. Therefore, Kc-ZNPs could be a potential delivery system for fat-soluble drugs.


Assuntos
Carragenina/química , Curcumina/farmacologia , Composição de Medicamentos , Nanopartículas/química , Polissorbatos/química , Zeína/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura , Fatores de Tempo
4.
Pharmaceutics ; 11(11)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703324

RESUMO

Curcumin (Cur) has anticancer activities but has poor stability, which can be improved using carrier materials. In this study, chitosan was aminated to increase the number of amino groups on its surface, modified with folic acid (FA), and then made into nanoparticles by ionic crosslinking. Owing to ion interaction, the negatively charged, non-toxic tripolyphosphate (TPP) interacted with the positively charged amino group on the aminated chitosan (AmCS) surface, producing FA-AmCS-TPP nanoparticles, which were then characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectrophotometry (FT-IR), and thermogravimetric analysis (TGA). Their small particle size (175.2 ± 0.99 nm) and good surface positive potential (+42.4 mV) are beneficial for carrying antitumor drugs. We subsequently investigated whether coating of Cur by AmCS allows slow drug release by FA-AmCS-TPP nanoparticles in different pH environments, and estimated the Cur loading efficiency (EE-Cur). Our results showed that the cumulative release rate of Cur at 48 h was 56.2%, and that the EE-Cur reached 94.26 ± 0.91% with nanoparticles composed of 0.10 g AmCS, 10.0 mg FA, 10.0 mg TPP, and 15.0 mg Cur. Additionally, cytotoxicity experiments showed that the Cur/FA-AmCS-TPP nanoparticles had good targeting ability for tumor cells. Therefore, the non-toxic targeted composite nanoparticles had potential as a new antitumor agent that can overcome the limitations of Cur.

5.
Ciênc. rural (Online) ; 47(12): e20170241, Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1044938

RESUMO

ABSTRACT: Wheat (Triticum aestivum L.) stem development significantly affects grain yield. The dwarf plants (D) of wheat mutant dms was less than 30cm. Here, we were to explore the molecular basis for the restrained stem development of the dwarf plants. The results were reached by compare the young spikes and stems transcriptomes of the tall (T) and D plants of mutant dms. We identified 663 genes highly expressed in stem tips. We identified 997 differentially expressed genes (DEGs) in stem tips between T and D, 403 DEGs were significantly related with stem development. Most biological processes in stem tips on dwarf plants were significantly suppressed, such as phytohormone signaling etc. The sequencing analysis results were confirmed by quantitatively analysis the expression profiles of fourteen key DEGs via real-time QRT-PCR. We identified a group genes related to wheat stem development, identified a group DEGs related to the restrained stem development of D plants of dms. The suppressed phytohormone signaling, carbohydrate transport and metabolism were the major causal factors leading to dwarf plants of D. Our dataset provides a useful resource for investigating wheat stem development.


RESUMO: O desenvolvimento da haste do trigo (Triticum aestivum L.) afeta significativamente o rendimento dos grãos. A partir disso, empregou-se a base molecular para o desenvolvimento de uma haste de variedade de trigo. Os resultados foram alcançados ao conferir as hastes de um mutante de trigo DMS. Identificou-se 663 genes altamente expressos na haste; 997 genes (DEGs) diferentemente expressos em hastes entre T e D e; 403 DEGs foram significativamente diferentes. A maioria dos processos biológicos de caule tipo não plantas foram significativamente suprimidas, com o fito hormônio de sinalização. Os resultados da análise de sequencia foram confirmados pela expressão quantitativa de perfis de catorze chave DEGs através de qRT-PCR em tempo real. Nota-se um grupo de genes relacionados com a haste de trigo de desenvolvimento. Identificou-se um grupo DEGs relacionados com o desenvolvimento de um tronco D plantas de DMS. O fito hormônio de sinalização, transporte e metabolismo de hidratos de carbono foram os principais fatores suscetíveis das plantas anão de D. Nosso conjunto de dados fornece um recurso útil para investigar o desenvolvimento do caule de trigo.

6.
PLoS One ; 11(3): e0149287, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26982202

RESUMO

BACKGROUND: Wheat (Triticum aestivum L.) spike development is the foundation for grain yield. We obtained a novel wheat mutant, dms, characterized as dwarf, multi-pistil and sterility. Although the genetic changes are not clear, the heredity of traits suggests that a recessive gene locus controls the two traits of multi-pistil and sterility in self-pollinating populations of the medium plants (M), such that the dwarf genotype (D) and tall genotype (T) in the progeny of the mutant are ideal lines for studies regarding wheat spike development. The objective of this study was to explore the molecular basis for spike abnormalities of dwarf genotype. RESULTS: Four unigene libraries were assembled by sequencing the mRNAs of the super-bulked differentiating spikes and stem tips of the D and T plants. Using integrative analysis, we identified 419 genes highly expressed in spikes, including nine typical homeotic genes of the MADS-box family and the genes TaAP2, TaFL and TaDL. We also identified 143 genes that were significantly different between young spikes of T and D, and 26 genes that were putatively involved in spike differentiation. The result showed that the expression levels of TaAP1-2, TaAP2, and other genes involved in the majority of biological processes such as transcription, translation, cell division, photosynthesis, carbohydrate transport and metabolism, and energy production and conversion were significantly lower in D than in T. CONCLUSIONS: We identified a set of genes related to wheat floral organ differentiation, including typical homeotic genes. Our results showed that the major causal factors resulting in the spike abnormalities of dms were the lower expression homeotic genes, hormonal imbalance, repressed biological processes, and deficiency of construction materials and energy. We performed a series of studies on the homeotic genes, however the other three causal factors for spike abnormal phenotype of dms need further study.


Assuntos
Genes de Plantas , Mutação , Transcriptoma , Triticum/genética , Perfilação da Expressão Gênica , RNA Mensageiro/genética
7.
Luminescence ; 31(1): 135-40, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26014423

RESUMO

BiPO4 and Eu-doped BiPO4 crystals were synthesized via a simple precipitation route at room temperature, employing Bi(NO3)3 and (NH4)2HPO4 as the reactants, Eu2O3 as the dopant and citric acid as a template. X-ray powder diffraction analyses showed that pure rhombohedral BiPO4 form was obtained, and was the preferential orientation growth of the crystal. Field emission scanning electron microscope observations showed that the concentration of Bi(3+) obviously changed the products' morphologies from nanosphere, hollow sphere to hexagonal prism. The acidity of the solution and the contents of citric acid and Eu(3+) ion tailored the size of the final crystals. Effects of concentration of Eu(3+) ion on the luminescence emission intensity were also investigated.


Assuntos
Bismuto/química , Európio/química , Luminescência , Nanoestruturas/química , Fosfatos/química
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 23(6): 1198-201, 2006 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-17228708

RESUMO

The dielectric spectroscopy of human blood cells was measured within the frequency range of 0.01-100 MHz, and the dielectric numerical characters were determined as response to AC electric field. we measured the AC impedance of normal human blood cells with the impedance technique in the frequency domain, then the experimental data were drawn a relationship curve between the frequency of electric field and conductivity. The dielectric spectrum and the Cole-Cole plots of human blood cells were established. The characteristics of dielectric response of human blood cells were also established. The permittivity and the conductivity of human blood cells were frequency dependent, and dielectric dispersion of human blood cells had two characteristic frequencies: i.e. fc1, is 1.42 MHz, and fc2 is 3. 32 MHz.


Assuntos
Células Sanguíneas/fisiologia , Condutividade Elétrica , Análise Espectral/métodos , Eletroquímica , Humanos
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