Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Mais filtros

Base de dados
Intervalo de ano de publicação
J Biomater Sci Polym Ed ; : 1-18, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31724490


Biological modifications of the silk fibroin (silk) material have broad applications in textiles, biomedical materials and other industrial materials. It is economical to incorporate nanoparticles to the biosynthesis of silk fibroin by adding them to silkworm larval diets. This strategy may result in the rapid stable production of modified silk. Glucose-coated silver nanoparticles (AgNPs) were used to improve the AgNPs' biocompatibility, and the AgNPs were efficiently incorporated into silk by feeding. Larvae fed with AgNPs produced silk with significantly improved antibacterial properties and altered silk secondary structures. Both positive and negative effects on the growth and synthesis of silk proteins were observed after different AgNPs doses. Larvae feeding with low concentration of 0.02% and medium 0.20% AgNPs have greater transfer efficiencies of AgNPs to silk compared with feeding high concentration of 2.00% AgNPs. In addition, the elongation and tensile strength of the produced silk fibers were also significantly increased, with greater mammalian cell compatibility. The appropriate AgNPs concentration in the diet of silkworms can promote the synthesis of silk proteins, enhance their mechanical properties, improve their antibacterial property and inhibit the presence of Gram-negative bacteria.

Int J Mol Med ; 42(2): 1034-1043, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29767261


Studies have shown that oleuropein has antifungal, anti­inflammatory, antiviral, antioxidant, anticancer and hypoglycemic functions. TTC solution staining was used to measure myocardial infarction size. A commercial kit was used to measure lactate dehydrogenase (LDH), creatinine kinase­MB (CK­MB), tumor necrosis factor­α (TNF­α), interleukin­1ß (IL­1ß), IL 6, superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and catalase levels. Western blot analysis was used to measure p53, p-MEK p-ERK and p­IκBα protein expression. The present study reports that the protective effect of oleuropein also prevents against myocardial ischemia/reperfusion (myocardial I/R). The aim of this retrospective study was to evaluate this protective effect of oleuropein and the mechanisms by which myocardial I/R is prevented. Oleuropein inhibited myocardial infarction size, CK­MB and LDH serum levels in a myocardial I/R rat model. Moreover, oleuropein also attenuated caspase­3 activity, and p53, phosphorylated (p)­mitogen­activated protein kinase kinase (MEK), p­extracellular signal­regulated protein kinase (ERK) and p­IκBα protein expression. TNF­α, IL­1ß, IL­6 and MDA were decreased; SOD, GSH and catalase levels inhibited TNF­α, IL­1ß, IL-6 and MDA levels, and increased SOD, GSH and catalase levels in myocardial I/R rats treated with oleuropein. Rats orally administered the MEK inhibitor PD0325901, in addition to oleuropein, exhibited inhibited myocardial infarction size, CK­MB and LDH serum levels compared with rats treated with oleuropein only. Rats treated with MEK inhibitor also exhibited suppressed caspase­3 activity, p53, p­MEK p­ERK and p­IκBα protein expression, TNF­α, IL­1ß, IL­6, SOD, GSH, MDA and catalase levels, and induced p­signal transducer and activator of transcription 3 (STAT3) protein expression compared with rats treated with oleuropein only. Taken together, these results suggest that MEK/ERK/STAT3 signaling regulates the inhibition of myocardial I/R in rats treated with oleuropein.

Cardiotônicos/uso terapêutico , Iridoides/uso terapêutico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Ratos Sprague-Dawley
Sci Rep ; 6: 34182, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27669995


Sexual glands are key sites affected by nanotoxicity, but there is no sensitive assay for measuring reproductive toxicity in animals. The aim of this study was to investigate the toxic effects of cadmium telluride quantum dots (CdTe-QDs) on gonads in a model organism, Bombyx mori. After dorsal vein injection of 0.32 nmol of CdTe-QDs per individual, the QDs passed through the outer membranes of gonads via the generation of ROS in the membranes of spermatocysts and ovarioles, as well as internal germ cells, thereby inducing early germ cell death or malformations via complex mechanisms related to apoptosis and autophagy through mitochondrial and lysosomal pathways. Histological observations of the gonads and quantitative analyses of germ cell development showed that the reproductive toxicity was characterized by obvious male sensitivity. Exposure to QDs in the early stage of males had severe adverse effects on the quantity and quality of sperm, which was the main reason for the occurrence of unfertilized eggs. Ala- or Gly-conjugated QDs could reduce the nanotoxicity of CdTe-QDs during germ cell development and fertilization of their offspring. The results demonstrate that males are preferable models for evaluating the reproductive toxicity of QDs in combined in vivo/in vitro investigations.

Sichuan Da Xue Xue Bao Yi Xue Ban ; 43(6): 926-9, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23387230


UNLABELLED: OBJECITVE: To explore the block effect of brain-derived neurotrophic factor (BDNF) antibody on the mitogen extracellular kinase (MEK) expression in lung tissues of rats with brain ischemia. METHODS: Adult SD rats were divided into sham group, brain ischemia lung injury (BILI) group, and BDNF antibody treated group. Lung tissues were harvested at 3 days after operation. The distribution of MEK in the lung tissue was studied by immunhistochemistry, and the optical density values of MEK immunostaining was used to compare the difference of each group (n=5). RT-PCR was used to determine the block effect of BDNF antibody on the level of MEK mRNA (n=8). RESULTS: Immunohistochemistry showed that MEK immunoreactive positive products were observed in endothelia cells of airway and blood vessels. The optical density value in rats with brain ischemia significantly increased, compared with sham one (P<0.05). Moreover, BDNF antibody block could reverse this increase of BDNF immunostaining intensity (P<0.05). RT-PCR showed that BDNF antibody block significantly decreased the expressional level of MEK mRNA in the lung tissues with brain ischemia (P<0.05). CONCLUSION: BDNF antibody block leads to a significant reduction of MEK expression in endothelia cells of lung tissue in the rats with brain ischemia.

Anticorpos/farmacologia , Isquemia Encefálica/metabolismo , Fator Neurotrófico Derivado do Encéfalo/imunologia , Lesão Pulmonar/metabolismo , Pulmão/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Animais , Isquemia Encefálica/complicações , Regulação para Baixo , Feminino , Lesão Pulmonar/etiologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley