Mesenchymal stem cells can affect solid organ allograft survival.
ABSTRACT It has recently been recognized that mesenchymal stem cells (MSCs) isolated from adult bone marrow are able to modify the alloimmune response in vitro and in vivo. MSCs can be expanded into large quantities in culture, thereby facilitating potential future applications in solid organ transplantation. To develop novel MSC-based antirejection treatments, the mechanism behind the immunomodulatory ability of MSCs has to be elucidated further. At present, a variety of possible in vitro effects of MSCs on immune system effector cells have been reported, but little is known about their in vivo properties. Here, we discuss recent findings regarding the influence of MSCs on different effector cell populations in vitro and summarize the available data describing their in vivo properties.
Conference Paper: High-speed systolic implementation of fast QR adaptive filters[Show abstract] [Hide abstract]
ABSTRACT: A rectangular systolic array of processing units is presented for implementation of the QR adaptive filter. This array requires approximately 8 N processing units to exactly solve the least-squares adaptive filtering problem using QR factorization. If a processing unit takes 50 ns to perform a task, the array can be implemented at an adaptive-filter input sampling rate of 20 MHz, with no loss in characteristic high performance (of least squares), numerical stability, or accuracy. This improves on widely used gradient methods for adaptive filtering, which must insert increasing amounts of performance-degrading delay into the adaptive updating when either the speed of implementation or number of taps increase. A discussion of the structure and interconnection of the processing units is included, as well as computer simulations that verify the stability and performance of the adaptive processing arrayAcoustics, Speech, and Signal Processing, 1988. ICASSP-88., 1988 International Conference on; 05/1988
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ABSTRACT: Recently, both embryonic stem cells and mesenchymal stem cells have been demonstrated to have immunosuppressive effects. The purpose of this study was to elucidate whether the embryonic stem cells and/or mesenchymal stem cells modulate both primary and secondary alloimmune responses. Both stem cells suppressed in vitro proliferation and cytokine production in primary alloimmune responses. They also suppressed in vitro proliferation and cytokine production of the allosensitized CD44+ memory T cells. However, they failed to prolong skin graft survival across both a major mismatch barrier (BALB/C, C57BL6/J) and a minor mismatch barrier (male to female). In conclusion, both embryonic stem cells and mesenchymal stem cells can suppress secondary alloimmune response in vitro as well as primary alloimmune responses; however, neither embryonic stem cells nor mesenchymal stem cells suppressed allograft rejection in stringent murine skin transplantation models.Transplant Immunology 07/2010; 23(3):141-6. · 1.52 Impact Factor
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ABSTRACT: An adaptive space-time processing system for dynamic spatial channels in a CDMA mobile communications network is presented. The proposed system consists of an adaptive sensor array that estimates the desired directions and waveforms, followed by adaptive linear equalizers that refine the waveform estimates by compensating for the mobile radio uplink channel. Capacity gains are achieved through code reuse, which is made possible by performing the spatial processing after the codes have been decorrelated with one another. Simulation results for a two sensor array in a variety of interference scenarios are presented in the form of bit error rate curves.Proceedings - ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing 01/1995; 3:1749-1752.