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Int J Pharm ; 494(1): 264-70, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26283278


In the present study, a composite system for the controlled and sustained release of hydrophobic/hydrophilic drugs is described. Composite hydrogels were prepared by blending silk fibroin (SF) with PLA-PEG-PLA copolymer under mild aqueous condition. Aspirin and indomethacin were incorporated into SF/Copolymer hydrogels as two model drugs with different water-solubility. The degradation of composite hydrogels during the drug release was mainly caused by the hydrolysis of copolymers. SF with stable ß-sheet-rich structure was not easily degraded which maintained the mechanical integrity of composite hydrogel. The hydrophobic/hydrophilic interactions of copolymers with model drugs would significantly alter the morphological features of composite hydrogels. Various parameters such as drug load, concentration ratio, and composition of copolymer were considered in vitro drug release. Aspirin as a hydrophilic drug could be controlled release from composite hydrogel at a constant rate for 5 days. Its release was mainly driven by diffusion-based mechanism. Hydrophobic indomethacin could be encapsulated in copolymer nanoparticles distributing in the composite hydrogel. Its sustained release was mainly degradation controlled which could last up to two weeks. SF/Copolymer hydrogel has potential as a useful composite system widely applying for controlled and sustained release of various drugs.

Preparações de Ação Retardada/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Fibroínas/química , Hidrogéis/química , Polímeros/química , Aspirina/química , Interações Hidrofóbicas e Hidrofílicas , Indometacina/química
Mater Sci Eng C Mater Biol Appl ; 51: 287-93, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25842137


Use of organic templates for controlling the growth of inorganic crystals is one of the research topics in biomimetic field. In particular, oriented growth of hydroxyapatite (HAp) in organic fibrous matrix is provided a new view angle to study biomineralization of bone and its potential biomedical applications. The crystallization of HAp in fibrous hydrogels could mimic such biomineralization. In this paper, we report HAp nanorod crystal synthesized successfully by a biomimetic method using calcium chloride and ammonium dihydrogen phosphate as reagents in the presence of silk fibroin/sodium alginate (SF/SA) fibrous hydrogels. The effects of influence factors such as mineral times, pH, and temperature on controlling HAp nanorod crystals are discussed. The elongated HAp nanorods with rectangular column are grown with the increase of mineral times in biomimetic process. By changing pH, HAp nanorod crystals are obtained at alkaline condition in fibrous hydrogels. Moreover, compared to other temperatures, rod-shaped HAp crystals were formed at 20°C. The results imply this to be an effective method for preparing HAp crystals with controllable morphology for bone repair application.

Alginatos/química , Durapatita/síntese química , Fibroínas/química , Hidrogéis/química , Impressão Molecular/métodos , Nanotubos/química , Substitutos Ósseos/síntese química , Cristalização/métodos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Teste de Materiais , Nanofibras/química , Nanofibras/ultraestrutura , Nanotubos/ultraestrutura , Tamanho da Partícula , Propriedades de Superfície
Artigo em Chinês | MEDLINE | ID: mdl-21171301


OBJECTIVE: To investigate the incidence rate of deviated nasal septum (DNS) of the young men who are going to join the army, and of the students in key high schools in Jimo, and record their educational background, then analysis the influence of DNS on the youth's learning quality. METHOD: Random select 3085 young men who are going to be recruited in 2006-2008, and 2628 students in 3 key high schools of Jimo. Investigate the two groups' incidence rate of DNS and make a correlative statistic analyses with their educational background. RESULT: There are 395 young men with DNS, which account 12.8% of the 3085 men, with the educational background of college degree and above account 3.0%; high school diploma 12.4%; junior secondary education 27.5%. One hundred and ninety-four students with DNS in key high schools, which account 7.4, and the subsequent entrance examination results shows, undergraduate students account 14.9%, junior college students and considerable education 32.5%, and graduates 52.6%. CONCLUSION: DNS can influence the learning quality of the adolescent. It is necessary to operate on those patients and improve the complaint symptom.

Aprendizagem , Septo Nasal/anormalidades , Adolescente , Escolaridade , Feminino , Humanos , Masculino , Estudantes , Adulto Jovem