Abstract: The present invention provides a vehicle for delivering various chemicals, compositions and proteins to stem cells and embryoid bodies. The vehicle may be biocompatible and biodegradable polymer microparticles. Typically the particles will contain at least a growth factor for delivery to the embryoid bodies, and generally the growth factor induces differentiation of the cells in the embryoid body along a specific lineage. The present invention also provides methods for directing differentiation of the cells in the embryoid body.

Abstract: The present invention provides a vehicle for delivering various chemicals, compositions and proteins to stem cells and embryoid bodies. The vehicle may be biocompatible and biodegradable polymer microparticles. Typically the particles will contain at least a growth factor for delivery to the embryoid bodies, and generally the growth factor induces differentiation of the cells in the embryoid body along a specific lineage. The present invention also provides methods for directing differentiation of the cells in the embryoid body.

Abstract: The present invention provides compositions and methods for inhibiting adhesions. The methods involve administering solutions containing hydrogel precursors such as polysaccharide derivatives, e.g., derivatives of hyaluronic acid, cellulose, or dextran, to a subject at a site where adhesions may form, e.g., as a consequence of surgery, injury, or infection. The hydrogel precursors, e.g., polysaccharide derivatives, become crosslinked following their administration to form a hydrogel that maintains tissue separation. In certain embodiments of the invention one or both solutions contains particles, e.g., polymeric nanoparticles or microparticles, so that a composite hydrogel containing the particles is formed. The solution(s), particle(s), or both, may contain a biologically active agent such as an agent that contributes to inhibiting adhesions. The biologically active agent may be covalently attached to a hydrogel precursor.

Abstract: Controlled release of pharmaceutical agents using microspheres or other controlled release systems are used to treat disease state characterized by aberrant electrical activity in excitable tissue. For the treatment of epilepsy, agents useful in the treatment of epilepsy may be delivered to the patient at the site of seizure origin to control seizure activity in a time release manner. The inventive system may also be useful in the treatment of cardiac arrhythmias and pre-term labor. Particularly useful pharmaceutical compositions comprising a site 1 sodium channel blocker are also provided.

Abstract: Microparticles that are designed to release their payload when exposed to acidic conditions are provided as a vehicle for drug delivery. Any therapeutic, diagnostic, or prophylatic agent may be encapsulated in a lipid-protein-sugar or polymeric matrix including a pH triggering agent to form pH triggerable microparticles. Preferably the diameter of the pH triggered microparticles ranges from 50 nm to 10 micrometers. The matrix of the particles may be prepared using any known lipid (e.g., DPPC), protein (e.g., albumin), or sugar (e.g., lactose). The matrix of the particles may also be prepared using any synthetic polymers such as polyesters. Methods of preparing and administering the particles are provided. Methods of immunization, transfection, and gene therapy are also provided by administering pH triggerable microparticles.