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Non-thermal irreversible electroporation (IRE) is a new, minimally invasive technique that has shown great promise for the ablation of tumors [1]. The procedure involves placing electrodes into or around a targeted tissue and delivering a series of low energy (intense but short) electric pulses for approximately one minute. These pulses induce irreversible structural changes in the cell membranes of the targeted tissue that lead to cell death. Because IRE affects only a single molecular component of the treated area, the cell membrane, it is the first true molecular surgery. IRE has the ability to create complete and predictable cell ablation with a sharp transition between normal and necrotic tissue.Copyright © 2009 by ASME

Laser therapies based on photochemical or photothermal mechanisms can provide a minimally invasive and potentially more effective treatment alternative to conventional surgical resection procedures by delivering prescribed optical/thermal doses to a targeted tissue volume with minimal damage to intervening and surrounding tissues. However laser therapy effectiveness is limited due to nonspecific excitation/heating of target tissue which often results in healthy tissue injury. Nanostructures targeted to tumor cells and utilized in combination with laser excitation can enhance treatment effectiveness by increasing thermal deposition and generating toxic photo-chemical mediators in the form of reactive oxygen species for targeted cell destruction.Copyright © 2009 by ASME

Tissue engineering is an emerging field that focuses on development of methods for repairing and regenerating damaged or diseased tissue. Successful development of engineered tissues is often limited by insufficient cellular proliferation and insufficient formation of extracellular matrix. To induce effective bone regeneration, many research groups have investigated the cellular response and capability for tissue regeneration associated with bioreactor conditions and addition of growth factors [1]. Bioreactors in tissue engineering have been developed to expose cells to a similar stress environment as found within the body or induce elevated stress levels for potential induction of specific cellular responses associated with tissue regeneration. Native bone encounters a diverse array of dynamic stresses such as shear, tensile, and compression daily. Stress conditioning protocols in the form of thermal or tensile stress have been shown to induce up-regulation of molecular chaperones called heat shock proteins (HSPs) and bone-related proteins like MMP13 (matrix metallopeptidase 13) [2] and OPG (osteoprotegerin) [3, 4]. HSPs have important roles in enhancing cell proliferation and collagen synthesis. Osteogenic growth factors such as TGF-β1 (transforming growth factor beta 1) and BMP-2 (bone morphogenetic protein 2) are related to bone remodeling and osteogenesis as well as HSP induction [5]. Therefore, identification of effective preconditioning using growth factors and stress protocols that enhance HSP expression could substantially advance development of bone regeneration. The purpose of this research was to identify preconditioning protocols using osteogenic growth factors and tensile stress applied through a bioreactor system to enhance expression of HSPs and bone-related proteins while minimizing cellular injury for ultimate use for bone regeneration.Copyright © 2009 by ASME

Development of dual diagnostic and therapeutic agents for cancer with heightened sensitivity, selectivity, and lower toxicity could greatly enhance the prognosis of patients suffering from this disease. Recent work by Dr. Harry Dorn of Virginia Tech has resulted in the creation of a novel nanostructure called a carbon nanotube peapod. This structure consists of multiple TNT EMF’s (Trimetallic nitride template endohedral metallofullerenes) contained within a single-walled carbon nanotube (CNT) in the form of a peapod. Using TNT EMFs containing gadolinium, this nanostructure can achieve a 40-fold improvement in magnetic resonance imaging (MRI) contrast enhancement [1]. The CNT component of the peapod can be utilized as a hyperthermia enhancer [2] and an effective platform for drug delivery [3]. This study focuses on the use of carbon nanotube peapods (CNT peapods) to absorb near infrared light and generate therapeutic heat for tumor destruction. With sufficient heating and nanoparticle targeted delivery to tumor cells, CNT peapods can potentially induce selective hyperthermia-mediated toxicity in tumors.