A preliminary list of the vascular plants of Higashi-hiroshima Campus, Hiroshima University, Hiroshima Pref., SW Japan <Data>

広島大学東広島キャンパスは広島県西条盆地の中央部に位置し，その敷地内には様々な植物が生育している。キャンパス内の維管束植物に関しては学内誌などに断片的に紹介されてきたが，1995年の移転完了後，網羅的な植物相の調査は行われていない。本稿ではキャンパス内の植物相の現状を把握するため，文献および生態実験園とぶどう池周辺を中心に行った調査にもとづいて，東広島キャンパスの維管束植物目録（101科210属286種）をまとめた。A preliminary list of the vascular plants of Higashi-hiroshima Campus in Hiroshima University (Hiroshima Pref., SW Japan) was reported based on own field researches and previous reports. A total of 286 native, naturalized and garden species, including infraspecific taxa, were recorded

Comparative analysis of the cellular entry of polystyrene and gold nanoparticles using the freeze concentration method

Despite advances in nanoparticle delivery, established physical approaches, such as electroporation and sonication, result in cell damage, limiting their practical applications. In this study, we proposed a unique freeze concentration-based technique and evaluated the efficacy of the method using two types of nanoparticles, citrate-capped gold nanoparticles and carboxylated polystyrene nanoparticles. We further compared the internalisation behaviour of particles of various sizes with and without freezing. Confocal microscopic images showed that the uptake efficacy for nanomaterials of 50 nm was greater than that of l00-nm particles. Polystyrene nanoparticles of 50 nm had more favourable adsorption and internalisation behaviours compared to those of gold nanoparticles after freeze concentration. We also examined the possible endocytic pathways involved in the uptake of gold and polystyrene nanoparticles, and found that the route differed between unfrozen and frozen conditions. Overall, we determined the influence of the freeze concentration strategy on both nanomaterial internalisation and the endocytic uptake pathway. Our findings provide a mechanistic understanding of the internalisation of nanoparticles using a freezing approach and thereby contribute to further developments in nanotherapeutic applications

Hydrophobic Amino Acid Tryptophan Shows Promise as a Potential Absorption Enhancer for Oral Delivery of Biopharmaceuticals

Cell-penetrating peptides (CPPs) have great potential to efficiently deliver drug cargos across cell membranes without cytotoxicity. Cationic arginine and hydrophobic tryptophan have been reported to be key component amino acids for cellular internalization of CPPs. We recently found that l-arginine could increase the oral delivery of insulin in its single amino acid form. Therefore, in the present study, we evaluated the ability of another key amino acid, tryptophan, to enhance the intestinal absorption of biopharmaceuticals. We demonstrated that co-administration with l-tryptophan significantly facilitated the oral and intestinal absorption of the peptide drug insulin administered to rats. Furthermore, l-tryptophan exhibited the ability to greatly enhance the intestinal absorption of other peptide drugs such as glucagon-like peptide-1 (GLP-1), its analog Exendin-4 and macromolecular hydrophilic dextrans with molecular weights ranging from 4000 to 70,000 g/mol. However, no intermolecular interaction between insulin and l-tryptophan was observed and no toxic alterations to epithelial cellular integrity&mdash;such as changes to cell membranes, cell viability, or paracellular tight junctions&mdash;were found. This suggests that yet to be discovered inherent biological mechanisms are involved in the stimulation of insulin absorption by co-administration with l-tryptophan. These results are the first to demonstrate the significant potential of using the single amino acid l-tryptophan as an effective and versatile bioavailability enhancer for the oral delivery of biopharmaceuticals