To assess the implantation effectiveness of porous scaffolds, it is essential to consider not only their mechanical properties but also their biological performance. Given the high cost, long duration and low reproducibility of biological experiments, simulation studies as a virtual alternative, have become a widely adopted and efficient evaluation method. In this study, based on the secondary development environment of finite element analysis software, the strain energy density growth criterion for bone tissue was introduced to simulate and analyze the cell proliferation-promoting effects of four different lattice porous scaffolds under cyclic compressive loading. The biological performance of these scaffolds was evaluated accordingly. The computational results indicated that in the early stages of bone growth, the differences in bone tissue formation among the scaffold groups were not significant. However, as bone growth progressed, the scaffold with a porosity of 70% and a pore size of 900 μm demonstrated markedly superior bone formation compared to other porosity groups and pore size groups. These results suggested that the scaffold with a porosity of 70% and a pore size of 900 μm was most conducive to bone tissue growth and could be regarded as the optimal structural parameter for bone repair scaffold. In conclusion, this study used a visualized simulation approach to pre-evaluate the osteogenic potential of porous scaffolds, aiming to provide reliable data support for the optimized design and clinical application of implantable scaffolds.
Tissue Scaffolds/chemistry* ; Porosity ; Finite Element Analysis ; Tissue Engineering/methods* ; Computer Simulation ; Bone Development ; Osteogenesis ; Humans ; Cell Proliferation

Objective To analyze and compare the strength of titanium alloy crystalline porous scaffolds and porous scaffolds with a triply periodic minimal surface(TPMS)structure and explore the effect of porosity on the equivalent elastic modulus and permeability.Methods Crystalline porous scaffolds(cell 1-4)and TPMS porous scaffolds(P-,G-,D-,and FKS-type)with the same porosity were constructed,and the equivalent elastic modulus,equivalent yield strength,and permeability of the scaffolds were calculated using finite element simulation.Results The elastic modulus of eight scaffolds was in the range of 5.1-10.4 GPa,the yield strength was in the range of 69-110 MPa,and the permeability of 4 crystalline scaffolds was in the range of 0.015-0.030 mm2.Conclusions With an increase in porosity,the elastic modulus and yield strength of the scaffold gradually decreased,and the permeability gradually increased.The cell 2-type scaffold is suitable for repairing defects at load-bearing bone sites because of its high elastic modulus and yield strength.The cell 3-type scaffold with a uniform stress distribution and a longer linear elasticity phase may be suitable for designing porous tibial platforms for knee joint prostheses.

OBJECTIVETo look for optimum extraction techniques for oleuropein by boiling olive leaves at low temperature and reduced pressure.

METHODAccording to single factor experiment (SFE) design, the effects of seven factors, the impact of seven factors, type of solvent, temperature, time, ratio of material to liquid, ethanol concentration, vacuum degree and extraction times, on extraction yield of oleuropein were investigated. Based on the results of SFE, four more important factors, temperature, time, ratio of material to liquid and ethanol concentration, were selected in L9 (3(4)) orthogonal experiment (OE) to compare with those extracted with traditional methods.

RESULTThe optimum conditions for boiling extraction of oleuropein at low temperature and reduced pressure were as follows: temperature 60 degrees C, time 20 min, ratio of material to liquid 1:30 and ethanol concentration 85%. The conditions presented an extraction yield of 5.90%.

CONCLUSIONCompared with traditional extraction methods and the ultrasound assisted extraction method, boiling extraction techniques at low temperature and reduced pressure were so quick and efficient that it has a good application prospect.

Iridoids ; Liquid-Liquid Extraction ; methods ; Olea ; chemistry ; Plant Leaves ; chemistry ; Pressure ; Pyrans ; chemistry ; Technology, Pharmaceutical ; methods ; Temperature