Characterization of an Amphiphilic Janus-Type Surface in the Cellulose Nanofibril Prepared by Aqueous Counter Collision.

Cellulose nanofibrils, which attract extensive attention as a bio-based, sustainable, high-performance nanofibril, are believed to be predominantly hydrophilic. This study aimed to prove the presence of an amphiphilic "Janus-type fiber surface" in water with hydrophobic and hydrophilic faces in a cellulose nanofibril (ACC-CNF) that was prepared by the aqueous counter collision method. We clarified the surface characteristics of the ACC-CNF by confocal laser scanning microscopy with a carbohydrate-binding module and congo red probes for the hydrophobic planes on the cellulose fiber surfaces and calcofluor white as hydrophilic plane probes. The results indicated the presence of both characteristic planes on a single ACC-CNF surface, which verifies an amphiphilic Janus-type structure. Both hydrophobic probes adsorbed onto ACC-CNFs for the quantitative evaluation of the degree of ACC-CNF surface hydrophobicity by Langmuir's adsorption theory based on the optimal maximum adsorption amounts for various starting raw material types.

Rapid typing of influenza viruses using super high-speed quantitative real-time PCR.

The development of a rapid and sensitive system for detecting influenza viruses is a high priority for controlling future epidemics and pandemics. Quantitative real-time PCR is often used for detecting various kinds of viruses; however, it requires more than 2h per run. Detection assays were performed with super high-speed RT-PCR (SHRT-PCR) developed according to a newly designed heating system. The new method uses a high-speed reaction (18s/cycle; 40 cycles in less than 20min) for typing influenza viruses. The detection limit of SHRT-PCR was 1 copy/reaction and 10(-1) plaque-forming unit/reaction for viruses in culture supernatants during 20min. Using SHRT-PCR, 86 strains of influenza viruses isolated by the Tokyo Metropolitan Institute of Public Health were tested; the results showed 100% sensitivity and specificity for each influenza A and B virus, and swine-origin influenza virus. Twenty-seven swabs collected from the pharyngeal mucosa of outpatients were also tested, showing positive signs for influenza virus on an immunochromatographic assay; the results between SHRT-PCR and immunochromatography exhibited 100% agreement for both positive and negative results. The rapid reaction time and high sensitivity of SHRT-PCR makes this technique well suited for monitoring epidemics and pre-pandemic influenza outbreaks.

Novel high-speed real-time PCR method (Hyper-PCR): results from its application to adenovirus diagnosis.

PCR, including real-time PCR, usually requires at least 1 h to obtain results. To shorten this time, a novel real-time PCR method (Hyper-PCR) was developed. This method utilizes high-speed DNA polymerase and a thin disc-type reaction vessel that can quickly alter the temperature of the reaction mixture in a newly developed PCR machine. Reactions capable of amplifying adenovirus (Ad) DNA can be completed within 11 min (3 temperature steps, 55 cycles). Hyper-PCR can detect 3.1-18.0 DNA copies/reaction of Ad types 1-4, 7, 8, 11, 15, 19, and 37. Hyper-PCR and conventional real-time PCR were applied to diagnose 147 clinical samples, and the results were compared. Hyper-PCR had a sensitivity of 100% (73/73) and a specificity of 100% (74/74), using conventional real-time PCR as the gold standard. Our newly developed PCR method, Hyper-PCR, was able to diagnose Ad infection within 17 min (not including the time for genome extraction). The thermocycling time of the novel PCR is faster than that of previously available PCR applications, and this method is thought to be potentially applicable to clinical and environmental diagnostics, where rapid diagnosis is important.