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For skin tissue engineering, an ideal scaffold should mimic the natural extracellular matrix of the native skin. In this study, we reported a novel elastic sub-micron fiber scaffold blending poly ( ε-caprolactone-co-lactide) (PLCL) and Pluronic at different ratios by electrospinning. PLCL and Pluronic were co-electrospun with the ratio of 100/0, 99/1, 95/5, 90/10, 85/15, and 75/25. These scaffolds were evaluated in terms of fiber morphology, mechanical properties, and hydrophilicity for the purpose of culturing adipose-derived stem cells (ADSCs). Cell attachment and proliferation on the scaffolds were also evaluated to demonstrate the potential of serving as a skin graft. The results indicated that all of the electrospun fibers possessed smooth surface textures and interconnected porous structures with the average diameter ranging from approximately 750-1140 nm. The higher tensile strength was observed in 95/5 and 90/10 PLCL/Pluronic blended membranes, while further incorporation of Pluronic almost has no effect on tensile strength. The water contact angle was 85° for scaffold with the ratio of 99/1, while 0° for 90/10, 85/15, and 75/25. In addition, the elevation of Pluronic content in composition resulted in a corresponding increase in swelling behavior. Compared with PLCL, the better cell adhesion and proliferation potential of ADSCs was exhibited on all PLCL/Pluronic blended scaffolds. ADSCs on the blended scaffolds were highly elongated and well integrated with the surrounding fibers, indicating the good cytocompatibility of PLCL/Pluronic scaffolds. Thus, these blended scaffolds have the potentially high application prospect in the field of skin tissue engineering. [ABSTRACT FROM AUTHOR]

Background: A coronal fracture of the posterior femoral condyle, also known as a Hoffa fracture, is an unusual injury, and there are only a handful of case reports or series exploring it. The optimal fixation method of these intraarticular fractures remains controversial; improper or unstable fixation usually lead to an unsatisfactory prognosis. The use of posterior-anterior or reversed lag screw fixation is still a popular method. Additional buttress plating is also recommended for fixation of these difficult fractures. The purpose of this study was to compare the mechanical strength of four different fixation patterns for this uncommon fracture.Material and Methods: Sixteen sawbone simulated models of Letenneur type I Hoffa fractures were created with one of four fixation patterns: two screws implanted in the anterior-posterior (AP) direction or posterior-anterior (PA) direction; one screw in the PA direction with a plate implanted in the posterior position of the distal femoral condyle or with a plate in the lateral position. Biomechanical testing was performed to determine the post-fixation axial stiffness, the maximum load to failure and the fragment vertical displacement for each of the four constructs.Results: The plate fixation patterns whether implanted in the posterior or lateral position were shown to provide higher overall axial stiffness and load to failure, and less vertical displacement than the other two patterns of pure screw fixation. Among these constructs, the lateral plate fixation was found to provide the highest stiffness and load to failure and the least displacement for the posterior condylar fragments, followed by the posterior plate fixation. The lowest overall stiffness and load to failure and the largest vertical displacement were found in the construct with the AP direction placed screws.Conclusion: It was concluded that the lateral position implanted plate is biomechanically the strongest fixation method for Letenneur type I Hoffa fractures. However, this plate fixation is not recommended for all cases. The choice of internal fixation pattern depends on the surgeons. [ABSTRACT FROM AUTHOR]