Nagoya Institute of Technology

About: Nagoya Institute of Technology is a education organization based out in Nagoya, Japan. It is known for research contribution in the topics: Thin film & Turbulence. The organization has 10766 authors who have published 19140 publications receiving 255696 citations. The organization is also known as: Nagoya Kōgyō Daigaku & Nitech.

Wearable ECG Based on Impulse-Radio-Type Human Body Communication

Abstract: Human body communication (HBC) provides a promising physical layer for wireless body area networks (BANs) in healthcare and medical applications, because of its low propagation loss and high security characteristics. In this study, we have developed a wearable electrocardiogram (ECG) which employs impulse radio (IR)-type HBC technology for transmitting vital signals on the human body in a wearable BAN scenario. The HBC-based wearable ECG has two excellent features. First, the wideband performance of the IR scheme contributed to very low radiation power so that the transceiver is easy to satisfy the extremely weak radio laws, which does not need a license. This feature can provide big convenience in the use and spread of the wearable ECG. Second, the realization of common use of sensing and transmitting electrodes based on time sharing and capacitive coupling largely simplified the HBC-based ECG structure and contributed to its miniaturization. To verify the validity of the HBC-based ECG, we evaluated its communication performance and ECG acquisition performance. The measured bit error rate, smaller than 10 $^{-3}$ at 1.25 Mb/s, showed a good physical layer communication performance, and the acquired ECG waveform and various heart-rate variability parameters in time and frequency domains exhibited good agreement with a commercially available radio-frequency ECG and a Holter ECG. These results sufficiently showed the validity and feasibility of the HBC-based ECG for healthcare applications. This should be the first time to have realized a real-time ECG transmission by using the HBC technology.

Engineering an Inward Proton Transport from a Bacterial Sensor Rhodopsin

Abstract: ATP is synthesized by an enzyme that utilizes proton motive force, and thus, nature has created various proton pumps. The best-understood proton pump is bacteriorhodopsin (BR), an outward-directed, light-driven proton pump in Halobacterium salinarum. Many archaeal and eubacterial rhodopsins are now known to show similar proton transport activity. We previously converted BR into an inward-directed chloride ion pump, but an inward proton pump has never been created. Proton pumps must have a specific mechanism to exclude transport in the reverse direction in order to maintain a proton gradient, and in the case of BR, a highly hydrophobic cytoplasmic domain may constitute such machinery. Here we report that an inward-directed proton transport can be engineered from a bacterial rhodopsin by a single amino acid replacement. Anabaena sensory rhodopsin (ASR) is a photochromic sensor in freshwater cyanobacteria that possesses little proton pump activity. When we replaced Asp217 in the cytoplasmic domain (a distanc...

N-methylated tetrahydroisoquinolines as dopaminergic neurotoxins

Abstract: N-Methylation of dopamine-derived 6,7-dihydroxyisoquinolines produces compounds whose chemical structures are similar to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). N-Methylation of 1,2,3,4-tetrahydroisoquinoline was proved by in vitro experiments using human brain homogenate as an enzyme source. By in vivo microdialysis in rat brains, N-methylation of 1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinolines (salsolinols) was also demonstrated. Among the brain regions examined, the activity of N-methylation was the highest in the substantia nigra. N-methyl-1,2,3,4-tetrahydroisoquinoline was oxidized to produce N-methyl-isoquinolinium ion by type A and type B monoamine oxidase prepared from human brain synaptosomal mitochondria. The structure of the oxidized isoquinoline is similar to that of 1-methyl-4-phenylpyridinium ion, a potent dopaminergic neurotoxin. These results indicate that these isoquinolines produced in or around dopamine neurons are N-methylated especially in substantia nigra and may be further oxidized by monoamine oxidase to produce ions. This biosynthesis pathway is quite similar to the oxidative synthesis of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. N-Methylation and oxidation of isoquinolines or other endogenous compounds may be involved in the pathogenesis of Parkinson's disease.