BACKGROUND Chitosan shows particularly high biocompatibility and fairly low cytotoxicity. However, chitosan is insoluble at physiological pH. Moreover, it lacks charge, so shows poor transfection. In order to develop a new type of gene vector with high transfection efficiency and low cytotoxicity, amphiphilic chitosan was synthesized and linked with low-molecular weight polyethylenimine (PEI). ...

Intravenously injected plasmid DNA (pDNA) complexed with cationic liposome (lipoplexes) caused NF-kappaB-mediated cytokine production from macrophages, induced by CpG sequence in the pDNA. We have reported that cytokine production caused by linear polyethyleneimine (PEI)-pDNA complexes (PEI polyplexes) was much lower than that caused by lipoplexes (Kawakami, S., Ito, Y., Charoensit, P., Yamashi...

hazelnuts are usually propagated by suckers or layering. however, other methods of propagation have been tested with variable results. grafting is a method that has a few advantages such as fast multiplication rate, earlier fruiting and reducing sucker removal cost on specific rootstocks. unfortunately, grafting is difficult due to slow formation of callus in hazelnuts. here, we report the hypo...

Liposome-based drug delivery systems hold great potential for cancer therapy. However, to enhance the localization of payloads, an efficient method of systemic delivery of liposomes to tumor tissues is required. In this study, we developed cationic liposomes composed of polyethylenimine (PEI)-conjugated distearoylglycerophosphoethanolamine (DSPE) as an enhanced local drug delivery system. The p...

Hazelnuts are usually propagated by suckers or layering. However, other methods of propagation have been tested with variable results. Grafting is a method that has a few advantages such as fast multiplication rate, earlier fruiting and reducing sucker removal cost on specific rootstocks. Unfortunately, grafting is difficult due to slow formation of callus in hazelnuts. Here, we report the hypo...

Polyethylenimine (PEI, especially with M(w) of 25,000) has been known as an efficient gene carrier and a gold standard of gene transfection due to its high transfection efficiency (TE). However, high concomitant cytotoxicity limited the application of PEI. In this report, several cationic polymers derived from low molecular weight (LMW) PEI (M(w) 600) linked with diglycidyl adipate (DA-PEI) or ...

Polyethylenimines (PEIs) of a molecular weight between 25 and about 800 kDa have successfully been used for in vitro and in vivo gene delivery approaches. Recent publications indicated that PEI molecules of lower molecular weight and a small molecular weight range are also efficient transfection reagents with a much lower cytotoxicity compared to high molecular weight PEIs. Here, we describe th...