Background-The development of minimally invasive, non-viral gene delivery vehicles for the central nervous system (CNS) is an important technology goal in the advancement of molecular therapies for neurological diseases. One approach is to deliver materials peripherally that are recognized and retrogradely transported by motor neurons toward the CNS. Tet1 is a peptide identified by Boulis and coworkers to possess the binding characteristics of tetanus toxin, which interacts specifically with motor neurons and undergoes fast, retrograde delivery to cell soma. In this work, Tet1-poly(ethylenimine) (Tet1-PEI) was synthesized and evaluated as a neurontargeted delivery vehicle.

In elevated-risk women with dense breasts, DWI can reveal cancers in addition to those detected on mammography alone with a low false-positive rate; these results suggest that DWI may have potential as a rapid supplemental screening tool.

Nanoparticles of ~10 nm in diameter made with chitosan or lactic acid-grafted chitosan were developed for high drug loading and prolonged drug release. A drug encapsulation efficiency of 92% and a release rate of 28% from chitosan nanoparticles over a 4-week period were demonstrated with bovine serum protein. To further increase drug encapsulation, prolong drug release, and increase chitosan solubility in solution of neutral pH, chitosan was modified with lactic acid by grafting D,L-lactic acid onto amino groups in chitosan without using a catalyst. The lactic acid-grafted chitosan nanoparticles demonstrated a drug encapsulation efficiency of 96% and a protein release rate of 15% over 4 weeks. With increased protein concentration, the drug encapsulation efficiency decreased and drug release rate increased. Unlike chitosan, which is generally soluble only in acid solution, the chitosan modified with lactic acid can be prepared from solutions of neutral pH, offering an additional advantage of allowing proteins or drugs to be uniformly incorporated in the matrix structure with minimal or no denaturization.

The radiologist has a critical role in recognizing and reporting excipient lung disease because the referring clinician may be unaware of the patient's i.v. drug abuse.