Enzymes involved in polyunsaturated fatty acid saturation metabolism in lactic acid bacteria and its application for functional lipid synthesis

Polyunsaturated fatty acids and probiotic lactic acid bacteria are reported to be effective to prevent metabolic syndrome. The mechanism, however, was not clear yet. We revealed the polyunsaturated fatty acid saturation metabolism in Lactobacillus plantarum AKU 1009a, which converted linoleic acid into conjugated linoleic acid (CLA)1). The enzyme system for this saturation metabolism was found to consist of four enzymes (hydratase2), dehydrogenase3), isomerase, enone reductase4)) and generate hydroxy fatty acids, oxo fatty acids, and conjugated fatty acids as intermediates. The homologous genes encoding these four enzymes were found in genome sequences of many gut microorganisms. Therefore, acting in concert, gut microbiota may mediate the unsaturated fatty acid saturation metabolism in gastrointestinal tract. Furthermore, we confirmed the existence of these fatty acids in host tissues depending on the existence of gut microbes using specific pathogen free (SPF) mouse and germ free mouse1). Successive analysis revealed health promoting activity of these hydroxy and oxo fatty acids, i.e., intestinal epithelial barrier protection5), anti-obesity6), and anti-diabetic activity7), etc. Therefore, we developed novel production system for these fatty acid metabolites using the enzymes from probiotic lactic acid bacteria8,9,10). 10-hydroxy-cis-12-octadecenoic acid (HYA), an initial intermediate of linoleic acid saturation, has immunomodulatory activity and ameliorates intestinal epithelial barrier impairment, etc5). HYA was found in foods such as cheese, bacon, milk and vegetable pickles, but at low level. We developed hydroxy fatty acid production process using fatty acid hydratase in probiotic lactic acid bacteria. HYA was produced from safflower oil rich in linoleic acid (approximately 75%) with high conversion rate of approximately 50% with Lactobacillus plantarum. We achieved the industrial scale production using 2,000 L fermenter and 500 L reactor. Other C18 Δ9 unsaturated fatty acids such as oleic acid, α-linolenic acid, and γ-linolenic acid were also converted to corresponding 10-hydroxy fatty acids. The various hydroxy fatty acids provided by this technology using fatty acid hydratase in probiotic lactic acid bacteria are promising as novel functional fatty acids. These studies could open a new application of the enzymes involved in polyunsaturated fatty acid saturation in lactic acid bacteria to novel functional lipid production. 1) S. Kishino, et al. : Proc. Natl. Acad. Sci. USA, 110, 17808 (2013). 2) M. Takeuchi, et al. : J. Biosci. Bioeng. 119, 636 (2015). 3) M. Takeuchi, et al. : J. Mol. Catal., B Enzym. 117, 7 (2015). 4) H. Feng, et al. : FEBS Journal, 282, 1526-1537 (2015). 5) J. Miyamoto, et al. : J. Biol. Chem., 290, 2902 (2015). 6) T. Nanthirudjanar, et al. : Lipids, 50, 1093-1102 (2015). 7) T. Goto, et al. : Biochem. Biophys. Res. Commun., 459, 597 (2015). 8) H. Sakurama, et al. : J. Lipid Res., 55, 1855 (2014). 9) M. Takeuchi, et al. : J. Appl. Microbiol., 120, 1282-1288 (2016). 10) M. Takeuchi, et al. : Biosci. Biotechnol. Biochem., 80, 2132-2137 (2016)

Masked Modeling Duo for Speech: Specializing General-Purpose Audio Representation to Speech using Denoising Distillation

Self-supervised learning general-purpose audio representations have demonstrated high performance in a variety of tasks. Although they can be optimized for application by fine-tuning, even higher performance can be expected if they can be specialized to pre-train for an application. This paper explores the challenges and solutions in specializing general-purpose audio representations for a specific application using speech, a highly demanding field, as an example. We enhance Masked Modeling Duo (M2D), a general-purpose model, to close the performance gap with state-of-the-art (SOTA) speech models. To do so, we propose a new task, denoising distillation, to learn from fine-grained clustered features, and M2D for Speech (M2D-S), which jointly learns the denoising distillation task and M2D masked prediction task. Experimental results show that M2D-S performs comparably to or outperforms SOTA speech models on the SUPERB benchmark, demonstrating that M2D can specialize in a demanding field. Our code is available at: https://github.com/nttcslab/m2d/tree/master/speechComment: Interspeech 2023; 5 pages, 2 figures, 6 tables, Code: https://github.com/nttcslab/m2d/tree/master/speec

<ORIGINAL ARTICLE>Localization of anti-monocyte/macrophage antibody-positive cells in periodontal tissue of rat maxillary molars after orthodontic tooth movement

To examine the localization of monoclonal anti-monocyte/macrophage (ED1) and macrophage (ED2) antibody-positive cells in periodontium, rat maxillary molar teeth were moved by insertion of band materials. The orthodontic tooth movement was elicited for 5 days, and paraffin-embedded maxillary teeth were stained by fluorescent immunocytochemistry and observed using a confocal laser scanning microscope. The localization of ED1-positive mononuclear cells in the experimental teeth was little different from that in the controls. While ED2-positive mononuclear cells were located throughout the periodontium on the distalside of controls, the number of positive cells decreased on the pressure side of the treated teeth. The present study suggested that most of the immunoreactive mononuclear cells on the distal side of controls are macrophages, while the positive cells on the pressure side of the experimental teeth are osteoclast precursors and a small number of macrophages

Detection of quantitative trait loci controlling pre-harvest sprouting resistance by using backcrossed populations of japonica rice cultivars

Backcrossed inbred lines (BILs) and a set of reciprocal chromosome segment substitution lines (CSSLs) derived from crosses between japonica rice cultivars Nipponbare and Koshihikari were used to detect quantitative trait loci (QTLs) for pre-harvest sprouting resistance. In the BILs, we detected one QTL on chromosome 3 and one QTL on chromosome 12. The QTL on the short arm of chromosome 3 accounted for 45.0% of the phenotypic variance and the Nipponbare allele of the QTL increased germination percentage by 21.3%. In the CSSLs, we detected seven QTLs, which were located on chromosomes 2, 3 (two), 5, 8 and 11 (two). All Nipponbare alleles of the QTLs were associated with an increased rate of germination. The major QTL for pre-harvest sprouting resistance on the short arm of chromosome 3 was localized to a 474-kbp region in the Nipponbare genome by the SSR markers RM14240 and RM14275 by using 11 substitution lines to replace the different short chromosome segments on chromosome 3. This QTL co-localized with the low-temperature germinability gene qLTG3-1. The level of germinability under low temperature strongly correlated with the level of pre-harvest sprouting resistance in the substitution lines. Sequence analyses revealed a novel functional allele of qLTG3-1 in Nipponbare and a loss-of-function allele in Koshihikari. The allelic difference in qLTG3-1 between Nipponbare and Koshihikari is likely to be associated with differences in both pre-harvest sprouting resistance and low-temperature germinability

Numerical and experimental investigations on thermal interaction between thermal plasma and solid polymer powders using induction thermal plasma technique

金沢大学大学院自然科学研究科電子科学The interaction between thermal plasma and polymer solid powders was investigated using the inductively coupled thermal plasma (ICTP) technique. Interaction between thermal plasmas and polymers is extremely important, for example, for design of down-sized circuit breakers, because it fundamentally affects the interruption capability of the circuit breakers. The ICTP technique was used in this work because it presents the advantages of no contamination and good repeatability. Polytetrafluoroethylene (PTFE), polymethylmethacrylate (PMMA), polyethylene (PE), and polyoxymethylene (POM) were treated as polymer materials. Numerical modelling for injection of polymer solid powders into Ar thermal plasma was also made including thermal interactions between thermal plasmas and polymer powders. Results showed that PMMA-ablated vapour has a higher plasma-quenching efficiency than others; the polymer solid properties affect the plasma-quenching ability indirectly. Comparison of the calculated results with experimental results showed good agreement from the viewpoints of the spatial distribution of ablated vapour concentration and the average solid particle velocity. © 2008 IOP Publishing Ltd

Spatial distribution of C2 spectra from induction thermal plasmas with polymer powder injection

金沢大学理工研究域電子情報学系The influence of polymer ablation on thermal plasmas was fundamentally investigated by using the induction thermal plasma technique. Polymer powders were directly subjected to Ar-induction thermal plasmas. A high-speed video camera, with a bandpass filter, was used to measure the spatial distribution of the spectral radiation intensity of C2 molecules included in the polymer-ablated vapor. Numerical prediction was also undertaken to obtain the C2 molecular fraction distribution. Results directly show the mixing aspects of polymer-ablated vapor with thermal plasmas. © 2008 IEEE

High efficacy of third generation EGFR inhibitor AZD9291 in a leptomeningeal carcinomatosis model with EGFR-mutant lung cancer cells

Leptomeningeal carcinomatosis (LMC) remarkably decreases the quality of life of EGFR-mutant lung cancer patients. In contrast to the lesions outside the central nervous system (CNS), molecular mechanisms of EGFR tyrosine kinase inhibitor (TKI) resistance in CNS lesions including LMC are largely unknown. In this study, we established an in vivo imaging model for LMC with EGFR mutant lung cancer cell lines harboring an exon 19 deletion in EGFR and evaluated the effect of first generation EGFR-TKIs, erlotinib, second generation afatinib, and third generation AZD9291. In PC-9/ffluc model, erlotinib treatment slowed the development of LMC. Importantly, treatment with afatinib or AZD9291 apparently delayed the development of LMC. Moreover, treatment with a higher dose of AZD9291, also associated with inhibited phosphorylation of EGFR downstream molecule S6, regressed LMC refractory to the aforementioned EGFR-TKI treatments. These observations suggest that the third generation EGFR-TKI AZD9291 may be an effective treatment for first or second generation EGFR-TKI resistant LMC caused by EGFR-mutant lung cancer