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Protein aggregation is the principal component of numerous protein misfolding pathologies termed proteinopathies, such as Alzheimer’s disease, Parkinson’s disease, prion disease, and AA amyloidosis with unmet treatment needs. Protein aggregation inhibitors have great potential for the prevention and treatment of proteinopathies. Here we report the development of an automated real-time microliter-scale high throughput screening (MSHTS) system for amyloid aggregation inhibitors using quantum-dot nanoprobes. Screening 504 crude extracts and 134 low molecular weight aromatic compounds revealed the relationship of amyloid-β (Aβ) aggregation inhibitory activities of plant extracts using a plant-based classification. Within the eudicots, rosids, Geraniales and Myrtales showed higher activity. Screening low molecular weight aromatic compounds demonstrated that the structure of tropolone endows it with potential Aβ aggregation inhibitory activity. The activity of the most active tropolone derivative was higher than that of rosmarinic acid. MSHTS also identified three chaperone molecules as tau aggregation inhibitors. These results demonstrate that our automated MSHTS system is a novel and robust tool that can be adapted to a wide range of compounds and aggregation-prone polypeptides.

In an Asian international multicenter phase II trial conducted in patients with peripheral T-cell lymphoma (PTCL), [F-18]FDG-PET/CT was used for evaluation of the therapeutic response. Standardization of the PET/CT scanners was necessary before patient enrollment. We therefore standardized the scanners by phantom tests based on the profile approved by the Quantitative Imaging Biomarkers Alliance (QIBA) of Radiological Society of North America (RSNA). The tests were conducted on 12 scanners in 12 facilities in compliance with the QIBA Profile and used National Electrical Manufacturers Association (NEMA) International Electrotechnical Commission (IEC) body phantoms. We measured three parameters (standardized uptake value [SUV], resolution and noise) and adjusted the imaging parameter values. The indexes recommended in the Japanese Society of Nuclear Medicine (JSNM) guideline were also evaluated. In a total of 12 facilities, 6 facilities required no change in imaging conditions and 6 facilities required changes in imaging parameters. After revision, the three measurements (SUV, resolution and noise) met QIBA criteria at all sites, but 10 of the 12 scanners did not meet JSNM criteria. We standardized imaging conditions using phantoms as required in the RSNA-QIBA profile for response evaluation by [F-18]FDG PET/CT images in a multicenter study.

Eight chlorinated alkylresorcinols, monochasiol A–H (1–8), were isolated from the fruiting bodies of Dictyostelium monochasioides. Compounds 1–8 were synthesized to confirm their structures and to obtain sufficient material for performing biological tests. Monochasiol A (1) selectively inhibited the concanavalin A-induced interleukin-2 production in Jurkat cells, a human T lymphocyte cell line. Monochasiols were biogenetically synthesized by the combination of biosynthetic enzymes relating to the principal polyketides, MPBD and DIF-1, produced by Dictyostelium discoideum.

Chitins are highly crystalline structures that are predominantly found in crustacean shells. Alpha-chitin is composed of microfibers, which are made up of nanofibrils that are 2-5 nm in diameter and 30 nm in length and embedded in a protein matrix. Crystalline nanofibrils can also be prepared by acid treatment. We verified the effect of chitin nanofibrils (NF) and nanocrystals (NC) on skin using a three-dimensional skin culture model and Franz cells. The application of NF and NC to skin improved the epithelial granular layer and increased granular density. Furthermore, NF and NC application to the skin resulted in a lower production of TGF-β compared to that of the control group. NF and NC might have protective effects to skin. Therefore, their potential use as components of skin-protective formulations merits consideration.

Bird populations were censused in relation to habitat size and vegetation in Obihiro, Hok-kaido, during the breeding season (late April to early June) and non-breeding season (early November to early February), 1986-88. Five parks of urban area (plots A, B, C, D, E) and two wood islands of suburban area (plots F, G) were selected as census plots. A total of 38 bird species were recorded in breeding season and 30 species in non-breeding season. Most of them were forest birds or birds prefering open habitats, and shrub-grassland birds were scarce. In breeding season, the abundant bird species included Motacilla alba, Carduelis sinica, Passer montanus and Corvus corone, which were common species in urban areas of Hokkaido. Common bird species in parks with high tree density were forest bird prefering wide variety of habitats or sparse woods such as Dendorocopos major, Hypsipetes amaurotis, Turdus chrysolaus, Aegithalos caudatus, Parus palustris, Parus major, Coccothrauste coccotraustes, and Sturnus philippensis. In non-breeding season, the main species were D. major, H. amaurotis, Turdus naumanni, A. caudatus, P. palustris, Parus ater, P. major, Sitta europaea, Passer montanus and C. corone in all parks and wood islands. In breeding season, the number of total and forest bird species, forest bird density and bird species diversity H' increased with increasing tree density and canopy cover. In non-breeding season, the number of forest bird species increased and the number of non-forest bird species decreased with incresing tree density. There was no signi-ficant relationship between bird species diversity and vegetation variables because of increasing diversity even in plots with low tree density in non-breeding season. Both in breeding and non-breeding seasons, per cent ground cover did not influence the number of bird species and bird species diversity because the ground cover consisted of lawn in most cases. In urbanized area, parks provide an important habitat for birds.

In order to elucidate the mechanism by which phenylglyoxylic acid (PGA) is reduced electrochemically in the presence of strychnine (SC) to form mandelic acid (MA), which exhibits an optically active property, conductometric studies were carried out. The formation of a 1:1 complex between PGA (or MA) and SC was suggested from the results that equimolar mixture of PGA (or MA) and SC showed a maximum decrease of conductivity. Equilibrium constants of the 1:1 complex of PGA–SC or MA–SC were determined from the results of conductivity measurements at various temperatures. The thermodynamic data were calculated. ΔH and ΔS were found to be +22 kJ mol−1 and +1.1×102 J K−1 mol−1 for both the PGA–SC complex and MA–SC complex.