In this study, a new functionalized peptide RLN was designed containing the bioactive motif link N, the amino terminal peptide of link protein. A link N nanofiber scaffold (LN-NS) was self-assembled by mixing peptide solution of RLN and RADA16. The characterization of LN-NS was tested using atomic force microscopy (AFM). The biocompatibility and bioactivity of this nanofiber scaffold for rabbit nucleus pulposus cells (NPCs) were also evaluated. This designer functionalized nanofiber scaffold exhibited little cytotoxicity and promoted NPCs adhesion obviously. In three-dimensional cell culture experiments, confocal reconstructed images testified that the functionalized LN-NS-guided NPCs migration from the surface into the hydrogel considerably, in which the RADA16 scaffold did not. Moreover, the functionalized LN-NS significantly stimulated the biosynthesis of extracelluar matrices (ECM) by NPCs. Our findings demonstrate that the functionalized nanofiber scaffold containing link N had excellent biocompatibility and bioactivity with rabbit NPCs and could be useful in the nucleus pulposus regeneration.

Pulmonary inhalation administration is an ideal approach to locally treat lung disease and to achieve systemic administration for other diseases. However, the complex nature of the structural characteristics of the lungs often results in the difficulty in the development of lung inhalation preparations. Nanocrystals technology provides a potential formulation strategy for the pulmonary delivery of poorly soluble drugs, owing to the decreased particle size of drug, which is a potential approach to overcome the physiological barrier existing in the lungs and significantly increased bioavailability of drugs. The pulmonary inhalation administration has attracted considerable attentions in recent years. This review discusses the barriers for pulmonary drug delivery and the recent advance of the nanocrystals in pulmonary inhalation delivery. The presence of nanocrystals opens up new prospects for the development of novel pulmonary delivery system. The particle size control, physical instability, potential cytotoxicity, and clearance mechanism of inhaled nanocrystals based formulations are the major considerations in formulation development.

No abstract

Reducing the mass of vehicles is an effective way to improve energy efficiency and mileage. Therefore, hot stamping is developed to manufacture lightweight materials used for vehicle production, such as magnesium and aluminum alloys. However, in comparison with traditional cold stamping, hot stamping is a high-energy-consumption process, because it requires heating sheet materials to a certain temperature before forming. Moreover, the process parameters of hot stamping considerably influence the product forming quality and energy consumption. In this work, the energy-economizing indices of hot stamping are established with multiobjective consideration of energy consumption and product forming quality to find a pathway by which to obtain optimal hot stamping process parameters. An energy consumption index is quantified by the developed models, and forming quality indices are calculated using a finite element model. Response surface models between the process parameters and energy-economizing indices are established by combining the Latin hypercube design and response surface methodology. The multiobjective problem is solved using a multiobjective genetic algorithm (NSGA-II) to obtain the Pareto frontier. ZK60 magnesium alloy hot stamping is applied as a case study to obtain an optimal combination of parameters, and compromise solutions are compared through stamping trials and numerical simulations. The obtained results may be used for guiding process optimization regarding energy saving and the method of manufacturing parameters selection.