Application of intelligent neural network method for prediction of mechanical behavior of wire-rope scaffold in tissue engineering

In tissue engineering, proper mechanical property is one of the key subjects for modeling tendon and ligament scaffolds. In this research, attempts were made to determine the factors of structural parameters of wire-rope silk scaffolds by using the intelligent neural network method to find optimum mechanical behavior for tendon and ligament regeneration. Experimental design of wire-rope scaffolds was made according to Taguchi orthogonal method. The input structural parameters were the number of filament and twist in each layer in four levels wire-rope and output was determined by an index that was defined according to mechanical properties of anterior cruciate ligament for young age group. Finally, a back-propagation neural network with a high accuracy was designed to predict the mechanical properties of wire-rope tendon and ligament scaffold and according to sensitivity analysis, the number of filaments and twist in outer layers is less important than other input parameters. Finally, a multiple linear regression, a most widely used statistical method, developed from the data.     

A composite of hydroxyapatite with electrospun biodegradable nanofibers as a tissue engineering material

Biodegradable and biocompatible poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), a copolymer of microbial polyester, was fabricated as a nanofibrous film by electrospinning and composited with hydroxyapatite (HAp) by soaking in simulated body fluid. Compared with a PHBV cast (flat) film, the electrospun PHBV nanofibrous film was hydrophobic. However, after HAp deposition, both of the surfaces were extremely hydrophilic. The degradation rate of HAp/PHBV nanofibrous films in the presence of polyhydroxybutyrate depolymerase was very fast. Nanofiber formation increased the specific surface area and HAp enhanced the invasion of enzyme into the film by increasing surface hydrophilicity. The surface of the nanofibrous film showed enhanced cell adhesion over that of the flat film, although cell adhesion was not significantly affected by the combination with HAp.     

聚己内酯/聚乙二醇大孔径纳米纤维膜的制备及其在组织工程支架中的应用

为使细胞在静电纺纳米纤维支架上得到更佳的生长与黏附,采用改进的静电纺丝装置制备具有良好生物相容性的聚己内酯(PLC)/聚乙二醇(PEG)大孔径复合纳米纤维膜,探究纺丝溶液中溶质质量配比与溶液质量分数对纳米纤维膜形貌及性能的影响,确定最佳工艺参数;将最佳工艺条件下制备的纳米纤维膜初步应用于组织工程,并与传统静电纺丝装置制备的纤维膜进行细胞相容性对比分析。结果表明:当PLC和PEG的混纺质量比为80∶20,纺丝溶液质量分数为25%时,获得的PCL/PEG大孔径纳米纤维膜质量最好;与传统静电纺PCL/PEG纳米纤维膜相比,PCL/PEG大孔径纳米纤维膜更利于细胞的生长和增殖,更适合作为组织工程支架材料。