Molecular and cellular mechanisms underlying the evolution of form and function in the amniote jaw.

The amniote jaw complex is a remarkable amalgamation of derivatives from distinct embryonic cell lineages. During development, the cells in these lineages experience concerted movements, migrations, and signaling interactions that take them from their initial origins to their final destinations and imbue their derivatives with aspects of form including their axial orientation, anatomical identity, size, and shape. Perturbations along the way can produce defects and disease, but also generate the variation necessary for jaw evolution and adaptation. We focus on molecular and cellular mechanisms that regulate form in the amniote jaw complex, and that enable structural and functional integration. Special emphasis is placed on the role of cranial neural crest mesenchyme (NCM) during the species-specific patterning of bone, cartilage, tendon, muscle, and other jaw tissues. We also address the effects of biomechanical forces during jaw development and discuss ways in which certain molecular and cellular responses add adaptive and evolutionary plasticity to jaw morphology. Overall, we highlight how variation in molecular and cellular programs can promote the phenomenal diversity and functional morphology achieved during amniote jaw evolution or lead to the range of jaw defects and disease that affect the human condition

Tumor Targeting by RGD-Grafted PLGA-Based Nanotheranostics Loaded with Paclitaxel and Superparamagnetic Iron Oxides

Theranostic nanoparticles have the potential to revolutionize cancer diagnosis and therapy. Many groups have demonstrated differential levels of tumor growth between tumors treated by targeted or untargeted nanoparticles; however, only few have shown in vivo efficacy in both therapeutic and diagnostic approach. Herein, we first develop and characterize dual-paclitaxel (PTX)/superparamagnetic iron oxide (SPIO)-loaded PLGA-based nanoparticles grafted with the RGD peptide, for a theranostic purpose. Second, we compare in vivo different strategies in terms of targeting capabilities: (1) passive targeting via the EPR effect, (2) active targeting of αvβ3 integrin via RGD grafting, (3) magnetic guidance via a magnet placed on the tumor, and (4) the combination of the magnetic guidance and the active targeting of αvβ3 integrin. In this chapter, we present the general flowchart applied for this project: (1) the polymer and SPIO synthesis, (2) the physicochemical characterization of the nanoparticles, (3) the magnetic properties of the nanoparticles, and (4) the in vivo evaluation of the nanoparticles for their therapeutic and diagnosis purposes. We employ the electron spin resonance spectroscopy and magnetic resonance imaging to both quantify and visualize the accumulation of theranostic nanoparticles into the tumors