Chapters authored
Radiolabelled Nanoparticles for Brain Targeting
Tumors like glioblastoma are inaccessible due to blood brain barrier. The permeability of radioisotopes can be improved by conjugating them with nanoparticles. The most common malignant adult brain tumor is glioblastoma, which has very poor patient prognosis. The mean survival for highly proliferative glioblastoma is only 10–14 months despite an aggressive radiotherapy and chemotherapy following debulking surgery. β− particle emitters like 131I, 90Y, 186/188Re, and 177Lu have been coupled with nanoparticles and used for treatment of glioblastoma. These radiopharmaceutical compounds have resulted in a stabilization and improvement of the neurological status with minimal side effects. Similarly, α particle emitters like 213Bi, 211At, and 225Ac are an innovative and interesting alternative. Alpha particles deliver a high proportion of their energy inside the targeted cells within a few micrometers from the emission point versus several millimeters for β− particles. Thus, α particles are highly efficient in killing tumor cells with minimal irradiation of healthy tissues and permits targeting of isolated tumor cells. This has been confirmed by subsequent clinical trials which showed better therapeutic efficacy and minimal side effects, thus opening a new and promising era for glioblastoma medical care using α therapy.
Part of the book: Medical Isotopes
Anti-Inflammatory Potential of Ginseng for Wound Healing
The recovery of skin wounds is a complex biological process involving three basic mechanisms: inflammatory phase, re-epithelialization followed by granulation and tissue remodeling. The interactions between inflammatory cells, fibroblasts, and keratinocytes induce microenvironmental changes at the wound site. Tissue remodeling is initiated by matrix-producing proteins and protease enzymes and collagen fibers in the dermis. A saponin extracted from ginseng, known as ginsenoside, has been shown to accelerate neovascularization in burn wounds in mice. It also increases levels of vascular endothelial growth factor and interleukin (IL-β). IL-β accelerate wound healing by promoting accumulation of macrophages at skin wound sites. Saponins are major active constituents of ginseng. They contain many ginsenosides. The purified ginsenosides or the extracts of ginseng root have been reported to have beneficial effects on damaged skin. For instance, red ginseng root extract protected skin from acute UVB-irradiation. Ginsenoside F1, an enzymatically modified derivative of the ginsenoside Rg1, protected HaCaT against UVB-induced apoptosis. Panax ginseng root extract promotes type I collagen synthesis in human dermal fibroblasts (HDF) via the Smad activation pathway and exhibits antioxidant activity against free radicles including diphenyl-p-picrylhydrazyl treatment. In addition, ginsenoside Rb1 promotes healing process of burn wound by enhancing angiogenesis. Among the various ginsenosides, ginsenoside Rb1 has been found to most potent agent for wound healing.
Part of the book: Ginseng