Narrow Results

A Specialized Nanoparticle for Detection of Cancer Cells.

Chinese Researchers to Carry out Studies on Human Reproductive Regulation.

This study outlines a drug delivery mechanism that utilizes two independent vehicles, allowing for delivery of chemically and physically distinct agents. The mechanism was utilized to deliver a new anti-cancer combination therapy consisting of piperlongumine (PL) and TRAIL to treat PC3 prostate cancer and HCT116 colon cancer cells. PL, a small-molecule hydrophobic drug, was encapsulated in poly (lactic-co-glycolic acid) (PLGA) nanoparticles. TRAIL was chemically conjugated to the surface of liposomes. PL was first administered to sensitize cancer cells to the effects of TRAIL. PC3 and HCT116 cells had lower survival rates in vitro after receiving the dual nanoparticle therapy compared to each agent individually. In vivo testing involved a subcutaneous mouse xenograft model using NOD-SCID gamma mice and HCT116 cells. Two treatment cycles were administered over 48 hours. Higher apoptotic rates were observed for HCT116 tumor cells that received the dual nanoparticle therapy compared to individual stages of the nanoparticle therapy alone.

Molecular imaging is an emerging field that introduces molecular agents into traditional imaging techniques, enabling visualization, characterization and measurement of biological processes at the molecular and cellular levels in humans and other living systems. The promise of molecular imaging lies in its potential for selective potency by targeting biomarkers or molecular targets and the imaging agents serve as reporters for the selectivity of targeting. Development of an efficient molecular imaging agent depends on well-controlled high-quality experiment design involving target selection, agent synthesis, in vitro characterization, and in vivo animal characterization before it is applied in humans. According to the analysis from the Molecular Imaging and Contrast Agent Database (MICAD, http://www.ncbi.nlm.nih.gov/books/NBK5330/), more than 6000 molecular imaging agents with sufficient preclinical evaluation have been reported to date in the literature and this number increases by 250–300 novel agents each year. The majority of these agents are radionuclides, which are developed for positron emission tomography (PET) and single photon emission computed tomography (SPECT). Contrast agents for magnetic resonance imaging (MRI) account for only a small part. This is largely due to the fact that MRI is currently not a fully quantitative imaging technique and is less sensitive than PET and SPECT. However, because of the superior ability to simultaneously extract molecular and anatomic information, molecular MRI is attracting significant interest and various targeted nanoparticle contrast agents have been synthesized for MRI. The first and one of the most critical steps in developing a targeted nanoparticle contrast agent is target selection, which plays the central role and forms the basis for success of molecular imaging. This chapter discusses the design principles of targeted contrast agents in the emerging frontiers of molecular MRI.

Nanotechnology and the exploitation of nanoparticles for clinical use have been considerably gaining grounds in medicine and varied fields of biological sciences. The advantages of using nanoparticles like sitespecific drug delivery, stability in vitro and in vivo as well as reduced side-effects compared to conventional drugs have made it the nextgeneration therapy for the treatment of diseases. However, toxicological studies have revealed that the uptake of novel nanomaterials may pose serious threats to health by ways of immune responses. Engineered nanoparticles from gold, carbon, metal oxides and polymers have been shown to affect the immune cells and organs in a number of ways. Herein, we have enumerated the potential implications of uptake and localization of certain widely used nanoparticles and their interaction with the immunological barrier inside living organisms. We have introduced a brief account of the various toxicological assessment tests currently being used by various research organization for ensuring the safety and efficacy of nanoparticles before being approved for human administration and consumption. Lastly, we have also tried to highlight some immerging new concepts of conjugating nanomaterials with biological molecules which, besides reducing inflammatory responses, increases the specificity of target thus improving the effect of nano-based drugs.