File No. 1417

First of all, I would like to share the great pleasure of the successful five-day symposium with every participant in the 5th Iketani Conference which was held in Kagoshima from April1S (Tuesday) to 22 (Saturday), 1995. Outstanding speakers enthusiastically presented their up-to-the-minute results. Relatively little time was allotted for each presentation to ensure asdnuch time· as possible for intensive discussions on the particular topics that had just been p~esented: I was delighted to see that the lectures were of high quality, and the discu,ssionswere lively, exciting, and productive in a congenial atmosphere. We also had 92 papers in the poster ·session, in which young (and relatively young) scientists made every effort to present the novel results of their research in advanced biomaterials and drug delivery systems (DDS). I believe some of the research is most promising and will become noteworthy in the twenty-first century. It was a privilege for me to deliver a lecture at the special session of the symposium. In my introductory remarks, I pointed out five key terms in multifaceted biomaterials research: materials design, concept or methodology, devices, properties demanded, and fundamentals. I am confident that innovative progress in device manufacturing for end-use, e.g., artificial organs, vascular grafts, and DDS, can be brought about only through properly designed advanced materials that exhibit the desired functionality at the interface with any living body.

This book covers a wide range of topics relating to carbon nanomaterials, from synthesis and functionalization to applications in advanced biomedical devices and systems. As they possess unique and attractive chemical, physical, optical, and even magnetic properties for various applications, considerable effort has been made to employ carbon nanomaterials (e.g., fullerenes, carbon nanotubes, graphene, nanodiamond) as new materials for the development of novel biomedical tools, such as diagnostic sensors, imaging agents, and drug/gene delivery systems for both diagnostics and clinical treatment. Tremendous progress has been made and the scattered literature continues to grow rapidly. With chapters by world-renowned experts providing an overview of the state of the science as well as an understanding of the challenges that lie ahead, Carbon Nanomaterials for Biomedical Applications is essential reading not only for experienced scientists and engineers in biomedical and nanomaterials areas, but also for graduate students and advanced undergraduates in materials science and engineering, chemistry, and biology.

The physiological role of the cellular prion protein (PrPc) is still not fully understood. This study gives a further insight into the possible physiological function(s) of PrPc via recognizing proteome changes influenced by different levels of PrPc expression in human embryonic kidney (HEK) 293 and PrPc-deficient (Prnp0/0 ) ell line. The two cell lines gave largely non-intersecting results. A high proportion of proteins deregulated following PrPc overexpression in HEK 293 cells is involved in energy metabolism and cellular homeostasis. Hence, the previously reported increased sensitivity of PrPc overexpressing cells to apoptotic stimuli might be caused by perturbed expression of proteins essential for energy production and maintenance of cellular homeostasis. A particularly significant point of the present study is PrPc overexpression-induced regulation of several proteins which are known to contribute to Alzheimer and Parkinson disease pathogenesis. This finding may be helpful in understanding the common molecular mechanisms underlying the pathogenesis of prion diseases and other neurodegenerative disorders. Conversely, the introduction of the human prion protein gene (PRNP) into Prnp0/0 cells correlated positively with regulation of proteins mainly implied in protection against oxidative stress and apoptosis. This finding is in line with earlier reports demonstrating rescue of Prnp0/0 neurons from apoptosis following an introduction of prion protein gene. Altogether, the presence/absence and the level of PrPc expression seem to be crucial for the fluctuation between PrPc's pro- and anti- apoptotic properties. In addition, this study provides first time evidence for PrPc-induced up-regulation of the glycolytic enzyme, lactate dehydrogenase (LDH) after transient focal cerebral ischemia in wild-type mice as compared to Prnp00 mice. The possibility that LDH and its product lactate, known to protect neural tissue against hypoxia/ischemia, might be involved in previously described PrPc-mediated neuroprotection against ischemic injury is considered.