Search

Gamma-aminobutyric acid (GABA), which has attracted much attention as a bioactive ingredient, is used in functional foods. Recently, electronic cigarette (e-cigarette) products for inhaling vaporized GABA have become commercially available. In this study, we developed a high-performance liquid chromatography-fluorescence method for detecting GABA derivatized with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) in cigarette smoke extract (CSE). The vaporized GABA captured in CSE was derivatized with DBD-F under moderate conditions (80°C, 30 min). After chromatographic separation, the DBD-GABA derivative was detected at 437 and 558 nm. The calibration curve of GABA ranging from 10 to 20,000 ng/mL showed good linearity (more than 0.999). The limit of detection at a signal-to-noise ratio of 3 was 1.1 ng/mL. The method was applied to the detection of GABA in e-liquid and CSE for two kinds of e-cigarette products, and the estimated collection efficiency of GABA was approximately 25%. Furthermore, the detection of minor components, such as glutamine, glutamic acid, and arginine, in the e-liquid proved that the GABA used in the e-cigarette was prepared by microbial fermentation., (© 2024 The Author(s). Luminescence published by John Wiley & Sons Ltd.)

[Purpose] This study aimed to elucidate the relationship between the Life-Space Assessment measure, which conceptualizes physical activity in terms of life-space, and indicators of empowerment, and physical function, in stable patients with chronic obstructive pulmonary disease. [Participants and Methods] This was a cross-sectional study. The participants were 25 stable outpatients with chronic obstructive pulmonary disease (22 males, mean age 75.6 ± 6.1 years). Measurements included the Life-Space Assessment; the Empowerment Scale for the Elderly; respiratory function; grip strength; weight-adjusted knee extension strength; and a six-minute walk test. Pearson's correlation coefficient and a multivariate analysis were used to examine the relationship between the Life-Space Assessment and each indicator, with the significance level set at 5%. [Results] The Life-Space Assessment score (83.4 ± 23.7 points) correlated with the percentage forced vital capacity and the six-minute walk distance. However, the Life-Space Assessment demonstrated no association with the Empowerment Scale for the Elderly (38.3 ± 7.0 points). [Conclusion]The results of this study suggest that physical function correlates with scores on the Life-Space Assessment in patients with stable chronic obstructive pulmonary disease., Competing Interests: The authors declare no conflicts of interest., (2024©by the Society of Physical Therapy Science. Published by IPEC Inc.)

Currently, e-cigarette products to inhale caffeine (Caf) are commercially available and widely used. Guarana extract (GE) is used as the caffeine source in some e-cigarette products. In this study, an LC-MS/MS analysis of components in the smoke from e-cigarettes with GE was performed. The concentration ranges of Caf and the minor components theophylline (TP), theobromine (TB), and paraxanthine (PX) in e-liquid and cigarette smoke extract (CSE) of five e-cigarette products were determined. The concentration ranges of e-liquid and CSE were 2.17-8.62 mg/mL and 0.17-1.17 µg/puff for Caf, 0.09-37.58 µg/mL and 0.03-11.88 ng/puff for TB, 50.28-185.26 ng/mL and 0.00-0.05 ng/puff for TP, and 0.44-4.09 µg/mL and 0.03-0.20 ng/puff for PX, respectively. By comparing the peak area ratios of e-liquid and CSE, we clarified that the heat degradation of Caf to its related components in GE products was accelerated. Epicatechin, which is another typical component in GE, was determined for CSE, but not for e-liquid., (© 2024. The Author(s), under exclusive licence to The Japan Society for Analytical Chemistry.)

Purpose: Electronic cigarettes (e-cigarettes) are used widely, and e-cigarettes containing caffeine (Caf) have recently become commercially available. However, no risk evaluation of these Caf-containing products has been performed to date. Such an evaluation requires a sensitive analytical method for quantifying Caf in smoke from e-cigarettes. The aim of this study was to establish a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying vaporized Caf from commercially available e-cigarettes, and to determine minor components related to Caf in cigarette smoke extract (CSE)., Methods: A sampling system for Caf using a suction pump was designed and sampling conditions were optimized., Results: The optimized LC-MS/MS conditions allowed the sensitive determination of Caf in smoke with a limit of detection of 0.03 ng/mL at a signal-to-noise ratio of 3. The method was applied to CSEs from five e-cigarette products and the concentration of Caf ranged from 0.894 ± 0.090 to 3.32 ± 0.14 μg/mL smoke (n = 3). Additionally, minor components related to Caf, such as theobromine, theophylline, and paraxanthine, were detected in CSE and in e-liquid at very low concentrations, indicating that they were impurities in e-liquid and vaporized along with Caf., Conclusion: This is the first report to determine the concentration of vaporized Caf using an LC-MS/MS method and to clarify several minor components in smoke from e-cigarettes., (© 2022. The Author(s), under exclusive licence to Japanese Association of Forensic Toxicology.)

The first phosphido derivative of the bis(bipyridine) ruthenium(ii) fragment, cis-[(bpy)2Ru(PPh2)2] ([RuP2]), has been developed and applied as a P-donor metalloligand to form new Ru-Rh, Ru-Ir and Ru2Cu2 heterometallic complexes. The Ru-Ir hydride complex [([RuP2])IrH(NCMe)3][BF4]2 exhibits significant catalytic activity for (E)-selective semi-hydrogenation of alkynes.

The inferotemporal cortex consists of an anterior (cytoarchitectonic area TE) and a posterior (area TEO) part, which together constitute the final areas of the ventral visual stream, which is critical for object discrimination. Area TE receives dense projections from area TEO. We have previously identified a response tolerance in the cells in area TE in monkeys to a range of viewing angles after object discrimination at each of several views. To investigate the contribution of area TEO to the establishment of such a response tolerance in area TE, we conducted electrophysiological recordings of the responses of the single cells in area TEO after performance saturation of object discrimination at several independent views, without any association across views, and compared them with those obtained from the TE cells. The cells in area TEO showed responses to the experienced object views, but not to nearby views. Comparisons of the tunings of the TE and TEO cells to different viewing angles for the same object sets in the same animal showed that cells in area TEO had a significantly narrower tuning width, whereas the response tolerance was usually observed in the TE cells across viewing angles up to 60°. Our findings revealed a significant difference in the representation of the object views between areas TE and TEO, and suggested that such a representation in area TE may be completed through neuronal mechanisms within area TE, which is not a property of the earlier stages of the ventral visual stream., (© 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

p-Nitrophenyl and eugenyl beta-primeveroside (6-O-beta-D-xylopyranosyl-beta-D-glucopyranoside) hydrolytic activity was found in culture filtrate from Penicillium multicolor IAM7153, and the enzyme was isolated. The enzyme was purified as a beta-primeverosidase-like enzyme by precipitation with ammonium sulfate followed by successive chromatographies on Phenyl Sepharose, Mono Q, and beta-galactosylamidine affinity columns. The molecular mass was estimated to be 50 kDa by SDS-PAGE and gel filtration. The purified enzyme was highly specific toward the substrate p-nitrophenyl beta-primeveroside, which was cleaved in an endo-manner into primeverose and p-nitrophenol, but a series of beta-primeveroside as aroma precursors were hydrolyzed only slightly as substrates for the enzyme. In analyses of its hydrolytic action and kinetics, the enzyme showed narrow substrate specificity with respect to the aglycon and glycon moieties of the diglycoside. We conclude that the present enzyme is a kind of beta-diglycosidase rather than beta-primeverosidase.