Correction of center of rotation and projection angle in synchrotron X-ray computed tomography.

An error in tomographic reconstruction parameters can result considerable artifacts in the reconstructed image, particularly in micro-computed tomography and nano-computed tomography. This study involved designing an automatic method for efficiently correcting errors resulting from incorrectly determined rotational axes and projection angles. In this method, errors are corrected by minimizing the "total variation" of a reconstructed image, and minimization is accomplished by using the gradient descent method.

Incorporation of exudates of human platelet-rich fibrin gel in biodegradable fibrin scaffolds for tissue engineering of cartilage.

The goal of this study was to assess the incorporation of exudates of human platelet-rich fibrin (hPRF) that is abundant in platelet cytokines and growth factors into biodegradable fibrin (FB) scaffolds as a regeneration matrix for promoting chondrocyte proliferation and re-differentiation. hPRF was obtained from human blood by centrifugation without an anticoagulant, and the exudate of hPRF was collected and mixed with bovine fibrinogen, and then thrombin was added to form the FB scaffold. Proliferation and differentiation of human primary chondrocytes and a human chondrosarcoma cell line, the SW-1353, embedded in the three-dimensional (3D) scaffolds and on the two-dimensional (2D) surface of the FB scaffolds so produced were evaluated in comparison with an agarose (AG) scaffold serving as the control.