“
“In this study, an optimization of xylanase expression by recombinant Pichia pastoris was carried out with a 2(3) factorial design. The influence of initial cell density, methanol and yeast nitrogen base concentration was evaluated, and the cell density was found to be the most important parameter. Considering AC220 with the yield of enzyme activity and the amount of methanol and YNB used
for fermentation, the optimal conditions in this study for enzyme production were 0.5% (w/v) methanol, 0.8% (w/v) YNB, and initial cell density of 3 x 10(8) cells/ml. The enzyme production in 15-l fermenter with the optimized conditions was performed and a twofold higher xylanase activity was obtained. The produced enzyme was practically free of cellulolytic activity. The molecular mass (21 kDa), optimal pH
(6.0) and substrate specificity of the enzyme were both identical to native enzyme. However, the thermostability of the recombinant enzyme was better than the native enzyme. The optimal temperature for the recombinant Xyn2 was 5 degrees C higher than native Xyn2, and remained at least 90% of its activity after 30 min Flavopiridol order incubation at 55 degrees C. The high level of fully active recombinant xylanase obtained in P. pastoris makes this expression system attractive for fermenter growth and industrial applications. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.”
“Study Design. Experimental rat animal study using a new cell delivery system.
Objective. To investigate the therapeutic effects with magnetic targeting
of bone marrow stromal cells (BMSCs) in a rat spinal cord injury (SCI) model.
Summary of Background Data. Several methods to deliver therapeutic agents have been used for the treatment of SCI in animal studies. However, the most appropriate administration method for clinical application has not been established. Previously, we reported the development of a new cell delivery system using magnetic targeting. This system has buy AZD1208 potential as a clinical application for a minimally invasive and efficient transplant method in SCI.
Methods. Contusion SCI was induced by placing a 25 g rod onto the spinal cord for 90 seconds in adult SD rats. A neodymium magnet was placed in the paravertebral muscles at the T7 level in the magnet group, whereas a nonmagnet metal was placed at the same spinal cord level in the nonmagnet group. Magnetically labeled BMSCs were injected into the subarachnoid space in both the magnet and nonmagnet group.
Results. Aggregations of the BMSCs were detected on the surface of the injured spinal cord in the magnet group, whereas few BMSCs were observed in the nonmagnet group. Hindlimb motor function of the magnet group demonstrated significant improvement compared with that of the nonmagnet group.
Conclusion. This cell delivery system may be a useful method for future clinical application in the treatment of SCI.”
“Background: During skin wounding and healing, skin homeostasis is interrupted.