10 research outputs found
Single-Photon Molecular Cooling
We propose a general method to cool the translational motion of molecules.
Our method is an extension of single photon atomic cooling which was
successfully implemented in our laboratory. Requiring a single event of
absorption followed by a spontaneous emission, this method circumvents the need
for a cycling transition and can be applied to any paramagnetic or polar
molecule. In our approach, trapped molecules would be captured near their
classical turning points in an optical dipole or RF-trap following an
irreversible transition process
Single-Photon Atomic Cooling
We report the cooling of an atomic ensemble with light, where each atom
scatters only a single photon on average. This is a general method that does
not require a cycling transition and can be applied to atoms or molecules which
are magnetically trapped. We discuss the application of this new approach to
the cooling of hydrogenic atoms for the purpose of precision spectroscopy and
fundamental tests.Comment: 4 pages and 3 figure
Neurogenic potential of engineered mesenchymal stem cells overexpressing VEGF.
Numerous signaling molecules are altered following nerve injury, serving as a blueprint for drug delivery approaches that promote nerve repair. However, challenges with achieving the appropriate temporal duration of recombinant protein delivery have limited the therapeutic success of this approach. Genetic engineering of mesenchymal stem cells (MSCs) to enhance the secretion of proangiogenic molecules such as vascular endothelial growth factor (VEGF) may provide an alternative. We hypothesized that the administration of VEGF-expressing human MSCs would stimulate neurite outgrowth and proliferation of cell-types involved in neural repair. When cultured with dorsal root ganglion (DRG) explants in vitro, control and VEGF-expressing MSCs (VEGF-MSCs) increased neurite extension and proliferation of Schwann cells (SCs) and endothelial cells, while VEGF-MSCs stimulated significantly greater proliferation of endothelial cells. When embedded within a 3D fibrin matrix, VEGF-MSCs maintained overexpression and expressed detectable levels over 21 days. After transplantation into a murine sciatic nerve injury model, VEGF-MSCs maintained high VEGF levels for 2 weeks. This study provides new insight into the role of VEGF on peripheral nerve injury and the viability of transplanted genetically engineered MSCs. The study aims to provide a framework for future studies with the ultimate goal of developing an improved therapy for nerve repair
Neurogenic Potential of Engineered Mesenchymal Stem Cells Overexpressing VEGF
Numerous signaling molecules are altered following nerve injury, serving as a blueprint for drug delivery approaches that promote nerve repair. However, challenges with achieving the appropriate temporal duration of recombinant protein delivery have limited the therapeutic success of this approach. Genetic engineering of mesenchymal stem cells (MSCs) to enhance the secretion of proangiogenic molecules such as vascular endothelial growth factor (VEGF) may provide an alternative. We hypothesized that the administration of VEGF-expressing human MSCs would stimulate neurite outgrowth and proliferation of cell-types involved in neural repair. When cultured with dorsal root ganglion (DRG) explants in vitro, control and VEGF-expressing MSCs (VEGF-MSCs) increased neurite extension and proliferation of Schwann cells (SCs) and endothelial cells, while VEGF-MSCs stimulated significantly greater proliferation of endothelial cells. When embedded within a 3D fibrin matrix, VEGF-MSCs maintained overexpression and expressed detectable levels over 21 days. After transplantation into a murine sciatic nerve injury model, VEGF-MSCs maintained high VEGF levels for 2 weeks. This study provides new insight into the role of VEGF on peripheral nerve injury and the viability of transplanted genetically engineered MSCs. The study aims to provide a framework for future studies with the ultimate goal of developing an improved therapy for nerve repair