Antioxidant loaded poly­(ε-caprolactone) (PCL) scaffolds were fabricated by electrospinning and then tested – mechanically and characterized via microscopy imaging. These mats are intended to be used in tissue repair or for wound healing, and their aim is to enhance the biocompatibility by reducing the inflammatory response related to biomaterials via the release of reactive oxygen species, (ROS)-responsive molecules, with antifibrotic properties over a certain length of time. Of the antioxidants studied, only allicin, curcumin, piperine, polydatin, and quercetin were found to be miscible with the polyester and gave rise to better processing by electrospinning and a greater homogeneity of the mats. The scaffolds of different fiber morphologies (micro-, nano-, or micronanostructured, the latter more closely mimicking the structure of the extracellular matrix of soft tissue) filled with 5% of antioxidant, showed a Young’s modulus and tensile strengths lower than those of pure PCL (i.e., elastic modulus of 5–9 MPa vs 12–27 MPa for PCL) but exhibited very interesting mechanical behavior for soft tissue engineered applications with elongation at breaks higher than 25% at room temperature. In a preliminary study, human adipose-derived mesenchymal stem cells were also seeded in several scaffolds and analyzed by fluorescence microscopy and showed that the cells were able to attach, survive, and grow in these 3D culture systems.

Ruiz-Ruiz M, Martinez-Trujillo JC. Human updating of visual motion direction during head rotations. J Neurophysiol 99: 2558 -2576, 2008. First published March 12, 2008 doi:10.1152/jn.00931.2007. Previous studies have demonstrated that human subjects update the location of visual targets for saccades after head and body movements and in the absence of visual feedback. This phenomenon is known as spatial updating. Here we investigated whether a similar mechanism exists for the perception of motion direction. We recorded eye positions in three dimensions and behavioral responses in seven subjects during a motion task in two different conditions: when the subject's head remained stationary and when subjects rotated their heads around an anteroposterior axis (head tilt). We demonstrated that after head-tilt subjects updated the direction of saccades made in the perceived stimulus direction (direction of motion updating), the amount of updating varied across subjects and stimulus directions, the amount of motion direction updating was highly correlated with the amount of spatial updating during a memory-guided saccade task, subjects updated the stimulus direction during a two-alternative forced-choice direction discrimination task in the absence of saccadic eye movements (perceptual updating), perceptual updating was more accurate than motion direction updating involving saccades, and subjects updated motion direction similarly during active and passive head rotation. These results demonstrate the existence of an updating mechanism for the perception of motion direction in the human brain that operates during active and passive head rotations and that resembles the one of spatial updating. Such a mechanism operates during different tasks involving different motor and perceptual skills (saccade and motion direction discrimination) with different degrees of accuracy.

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