著者
Ryo Nakabayashi Noriko Takeda-Kamiya Yutaka Yamada Tetsuya Mori Mai Uzaki Takashi Nirasawa Kiminori Toyooka Kazuki Saito
出版者
Japanese Society for Plant Biotechnology
雑誌
Plant Biotechnology (ISSN:13424580)
巻号頁・発行日
vol.38, no.3, pp.305-310, 2021-09-25 (Released:2021-09-25)
参考文献数
27
被引用文献数
7

Plants release specialized (secondary) metabolites from their roots to communicate with other organisms, including soil microorganisms. The spatial behavior of such metabolites around these roots can help us understand roles for the communication; however, currently, they are unclear because soil-based studies are complex. Here, we established a multimodal metabolomics approach using imaging mass spectrometry (IMS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to spatially assign metabolites under laboratory conditions using agar. In a case study using Catharanthus roseus, we showed that 58 nitrogen (N)-containing metabolites are released from the roots into the agar. For the metabolite assignment, we used 15N-labeled and non-labeled LC-MS/MS data, previously reported. Four metabolite ions were identified using authentic standard compounds as derived from monoterpene indole alkaloids (MIAs) such as ajmalicine, catharanthine, serpentine, and yohimbine. An alkaloid network analysis using dot products and spinglass methods characterized five clusters to which the 58 ions belong. The analysis clustered ions from the indolic skeleton-type MIAs to a cluster, suggesting that other communities may represent distinct metabolite groups. For future chemical assignments of the serpentine community, key fragmentation patterns were characterized using the 15N-labeled and non-labeled MS/MS spectra.
著者
Ryo Nakabayashi Noriko Takeda-Kamiya Yutaka Yamada Tetsuya Mori Mai Uzaki Takashi Nirasawa Kiminori Toyooka Kazuki Saito
出版者
Japanese Society for Plant Biotechnology
雑誌
Plant Biotechnology (ISSN:13424580)
巻号頁・発行日
pp.21.0504a, (Released:2021-06-24)
参考文献数
27
被引用文献数
7

Plants release specialized (secondary) metabolites from their roots to communicate with other organisms, including soil microorganisms. The spatial behavior of such metabolites around these roots can help us understand roles for the communication; however, currently, they are unclear because soil-based studies are complex. Here, we established a multimodal metabolomics approach using imaging mass spectrometry (IMS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to spatially assign metabolites under laboratory conditions using agar. In a case study using Catharanthus roseus, we showed that 58 nitrogen (N)-containing metabolites are released from the roots into the agar. For the metabolite assignment, we used 15N-labeled and non-labeled LC-MS/MS data, previously reported. Four metabolite ions were identified using authentic standard compounds as derived from monoterpene indole alkaloids (MIAs) such as ajmalicine, catharanthine, serpentine, and yohimbine. An alkaloid network analysis using dot products and spinglass methods characterized five clusters to which the 58 ions belong. The analysis clustered ions from the indolic skeleton-type MIAs to a cluster, suggesting that other communities may represent distinct metabolite groups. For future chemical assignments of the serpentine community, key fragmentation patterns were characterized using the 15N-labeled and non-labeled MS/MS spectra.
著者
Taro Noguchi Koh Shinohara Yasuhiro Tsuchido Satomi Yukawa Masaki Yamamoto Yasufumi Matsumura Michiko Hayashi Yutaka Yamada Akihiko Hayashi Tsunehiro Shimizu Miki Nagao
出版者
National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee
雑誌
Japanese Journal of Infectious Diseases (ISSN:13446304)
巻号頁・発行日
vol.75, no.2, pp.205-208, 2022-03-31 (Released:2022-03-24)
参考文献数
12

Transitioning from intravenous to oral antibiotic therapy for Escherichia coli bacteremia could reduce the length of hospital stay and drug costs without compromising efficacy. Despite the expansion of extended-spectrum β-lactamase (ESBL)-producing E. coli, limited data are available regarding the effectiveness of switching to oral antibiotic therapy in patients with bacteremia caused by this organism. To compare clinical outcomes between oral transition therapy and intravenous therapy in patients with bacteremia due to ESBL-producing E. coli with a urinary source, we conducted a retrospective cohort study at 3 Japanese hospitals. The effects were estimated by Cox hazard analysis using propensity scores. Among 996 patients with bacteremia due to E. coli, 73 were included in the study. In the adjusted analysis weighted by propensity scores including 26 patients in the oral switch group and 47 in the intravenous group, oral transition did not increase the risk of treatment failure within 60 days (adjusted hazard ratio 0.86, 95% confidence interval 0.18–4.10), whereas the length of hospital stay was shorter in the oral switch group than in the intravenous group (median, 12 days vs. 19 days, P = 0.04). Intravenous-to-oral transition may be an effective treatment option that shortens the hospital stay.