著者
Takahiro Sanada Tomoko Honda Fumihiko Yasui Kenzaburo Yamaji Tsubasa Munakata Naoki Yamamoto Makoto Kurano Yusuke Matsumoto Risa Kohno Sakiko Toyama Yoshiro Kishi Takuro Horibe Yudai Kaneko Mayumi Kakegawa Kazushige Fukui Takeshi Kawamura Wang Daming Chungen Qian Fuzhen Xia Fan He Syudo Yamasaki Atsushi Nishida Takayuki Harada Masahiko Higa Yuko Tokunaga Asako Takagi Masanari Itokawa Tatsuhiko Kodama Michinori Kohara
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
pp.JE20210324, (Released:2021-11-13)
参考文献数
26
被引用文献数
18

Background: Tokyo, the capital of Japan, is a densely populated city of >13 million people and thus at high risk of epidemic severe acute respiratory coronavirus 2 (SARS-CoV-2) infection. A serologic survey of anti–SARS-CoV-2 IgG would provide valuable data for assessing the city’s SARS-CoV-2 infection status. This cross-sectional study therefore estimated the anti–SARS-CoV-2 IgG seroprevalence in Tokyo.Methods: Leftover serum of 23,234 hospital visitors was tested for antibodies against SARS-CoV-2 using an iFlash 3000 chemiluminescence immunoassay analyzer (Shenzhen YHLO Biotech) with an iFlash–SARS-CoV-2 IgG kit (YHLO) and iFlash–SARS-CoV-2 IgG-S1 kit (YHLO). Serum samples with a positive result (≥10 AU/mL) in either of these assays were considered seropositive for anti–SARS-CoV-2 IgG. Participants were randomly selected from patients visiting 14 Tokyo hospitals between September 1, 2020, and March 31, 2021. No participants were diagnosed with coronavirus disease 2019 (COVID-19), and none exhibited COVID-19–related symptoms at the time of blood collection.Results: The overall anti–SARS-CoV-2 IgG seroprevalence among all participants was 1.83% (95% confidence interval [CI]: 1.66%-2.01%). The seroprevalence in March 2021, the most recent month of this study, was 2.70% (95% CI: 2.16%-3.34%). After adjusting for population age, sex, and region, the estimated seroprevalence in Tokyo was 3.40%, indicating that 470,778 individuals had a history of SARS-CoV-2 infection.Conclusions: The estimated number of individuals in Tokyo with a history of SARS-CoV-2 infection was 3.9-fold higher than the number of confirmed cases. Our study enhances understanding of the SARS-CoV-2 epidemic in Tokyo.
著者
Kosuke SODA Yukiko TOMIOKA Tatsufumi USUI Hiroichi OZAKI Hiroshi ITO Yasuko NAGAI Naoki YAMAMOTO Masatoshi OKAMATSU Norikazu ISODA Masahiro KAJIHARA Yoshihiro SAKODA Ayato TAKADA Toshihiro ITO
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.23-0122, (Released:2023-07-26)
被引用文献数
3

In the winter of 2010–2011, Japan experienced a large outbreak of infections caused by clade 2.3.2.1 H5N1 high pathogenicity avian influenza viruses (HPAIVs) in wild birds. Interestingly, many tufted ducks (Aythya fuligula), which are migratory diving ducks, succumbed to the infection, whereas only one infection case was reported in migratory dabbling duck species, the major natural hosts of the influenza A virus, during the outbreak. To assess whether the susceptibility of each duck species to HPAIVs was correlated with the number of cases, tufted duck and dabbling duck species (Eurasian wigeon, Mareca penelope; mallard, Anas platyrhynchos; Northern pintail, Anas acuta) were intranasally inoculated with A/Mandarin duck/Miyazaki/22M807-1/2011 (H5N1), an index clade 2.3.2.1 virus previously used for experimental infection studies in various bird species. All ducks observed for 10 days post-inoculation (dpi) mostly shed the virus via the oral route and survived. The tufted ducks shed a higher titer of the virus than the other dabbling duck species, and one of them showed apparent neurological symptoms after 7 dpi, which were accompanied by eye lesions. No clinical symptoms were observed in the dabbling ducks, although systemic infection and viremia were observed in some of them sacrificed at 3 dpi. These results suggest that the susceptibility of clade 2.3.2.1 HPAIVs might differ by duck species.
著者
Yusuke Fukazawa Naoki Yamamoto Takashi Hamatani Keiichi Ochiai Akira Uchiyama Ken Ohta
出版者
Information Processing Society of Japan
雑誌
Journal of Information Processing (ISSN:18826652)
巻号頁・発行日
vol.28, pp.16-30, 2020 (Released:2020-01-15)
参考文献数
114
被引用文献数
6

Monitoring mental health has received considerable attention as a countermeasure against the increasing occurrence of mental illness worldwide. However, current monitoring services incur costs because users are required to attach wearable devices or answer questions. To reduce such costs, many studies have used smartphone-based passive sensing technology to capture a user's mental state. This paper reviews those studies from the perspective of machine learning and statistical analysis. Forty-four studies published since 2011 have been reviewed and summarized from three perspectives: designed features, machine learning algorithm, and evaluation method. The features considered include location and mobility, activity, speech, sleep, phone usage, and context features. Tasks are classified as correlation analysis, regression tasks, and classification tasks. The machine learning algorithm used for each task is summarized. Evaluation metrics and cross validation methods are also summarized. For those who are not necessarily machine learning experts, we aim to provide information on typical machine learning framework for smartphone-based mental state estimation. For experts in the field, we hope this review will be a helpful tool to check for potential omissions.
著者
Takahiro Sanada Tomoko Honda Fumihiko Yasui Kenzaburo Yamaji Tsubasa Munakata Naoki Yamamoto Makoto Kurano Yusuke Matsumoto Risa Kohno Sakiko Toyama Yoshiro Kishi Takuro Horibe Yudai Kaneko Mayumi Kakegawa Kazushige Fukui Takeshi Kawamura Wang Daming Chungen Qian Fuzhen Xia Fan He Syudo Yamasaki Atsushi Nishida Takayuki Harada Masahiko Higa Yuko Tokunaga Asako Takagi Masanari Itokawa Tatsuhiko Kodama Michinori Kohara
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.32, no.2, pp.105-111, 2022-02-05 (Released:2022-02-05)
参考文献数
26
被引用文献数
4 18

Background: Tokyo, the capital of Japan, is a densely populated city of >13 million people, so the population is at high risk of epidemic severe acute respiratory coronavirus 2 (SARS-CoV-2) infection. A serologic survey of anti–SARS-CoV-2 IgG would provide valuable data for assessing the city’s SARS-CoV-2 infection status. Therefore, this cross-sectional study estimated the anti–SARS-CoV-2 IgG seroprevalence in Tokyo.Methods: Leftover serum of 23,234 hospital visitors was tested for antibodies against SARS-CoV-2 using an iFlash 3000 chemiluminescence immunoassay analyzer (Shenzhen YHLO Biotech, Shenzhen, China) with an iFlash–SARS-CoV-2 IgG kit (YHLO) and iFlash–SARS-CoV-2 IgG-S1 kit (YHLO). Serum samples with a positive result (≥10 AU/mL) in either of these assays were considered seropositive for anti–SARS-CoV-2 IgG. Participants were randomly selected from patients visiting 14 Tokyo hospitals between September 1, 2020 and March 31, 2021. No participants were diagnosed with coronavirus disease 2019 (COVID-19), and none exhibited COVID-19-related symptoms at the time of blood collection.Results: The overall anti–SARS-CoV-2 IgG seroprevalence among all participants was 1.83% (95% confidence interval [CI], 1.66–2.01%). The seroprevalence in March 2021, the most recent month of this study, was 2.70% (95% CI, 2.16–3.34%). After adjusting for population age, sex, and region, the estimated seroprevalence in Tokyo was 3.40%, indicating that 470,778 individuals had a history of SARS-CoV-2 infection.Conclusions: The estimated number of individuals in Tokyo with a history of SARS-CoV-2 infection was 3.9-fold higher than the number of confirmed cases. Our study enhances understanding of the SARS-CoV-2 epidemic in Tokyo.
著者
Ko NAKASUMI Naoki YAMAMOTO Taro TAKAMI Harumichi ITOH Kazuhito ITAMOTO Hiro HORIKIRIZONO Toshie ISERI Munekazu NAKAICHI Yuki NEMOTO Hiroshi SUNAHARA Kenji TANI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.21-0396, (Released:2021-12-06)
被引用文献数
3

Transcatheter arterial embolization (TAE) and transcatheter arterial chemoembolization (TACE) are standard treatments for advanced hepatocellular carcinoma (HCC) and particularly for unresectable tumors or liver metastases in humans. However, reports on TACE used in veterinary medicine are few. This study aimed to evaluate the feasibility and safety of drug-eluting bead transarterial chemoembolization (DEB-TACE). We performed DEB-TACE in four clinically normal dogs and pharmacokinetically compared the results against hepatic arterial infusion (HAI) of cisplatin in two dogs. Drug-eluting beads (DEB) loaded with cisplatin were injected through a microcatheter for selective embolization of the left hepatic artery. After embolization, computed tomography (CT) images and histological examination findings were obtained during a 4-week observation period. Serum platinum concentrations were measured to evaluate cisplatin after each procedure. Biochemical analysis was performed during a 12-week observation period. Embolization was successful in all dogs, and there were no clinically apparent abnormalities. Embolization was confirmed up to 4 weeks after DEB-TACE in two of the four dogs and up to 1 week in the other two dogs using postoperative CT images. Cisplatin was not detected in peripheral veins in all dogs after DEB-TACE, but it was detected in trace amounts after HAI. DEB-TACE using cisplatin was safe and well tolerated by normal dogs. DEB-TACE may be useful in terms of determining systemic toxicity and drug concentration within tumors.
著者
Nanako Takeda-Hirokawa Lian-Pin Neoh Hiroaki Akimoto Hiroshi Kaneko Takashi Hishikawa Iwao Sekigawa Hiroshi Hashimoto Shun-ichi Hirose Tsutomu Murakami Naoki Yamamoto Tohru Mimura Yutaro Kaneko
出版者
Center For Academic Publications Japan
雑誌
MICROBIOLOGY and IMMUNOLOGY (ISSN:03855600)
巻号頁・発行日
vol.41, no.9, pp.741-745, 1997 (Released:2008-03-17)
参考文献数
25

To clarify the mechanism by which curdlan sulfate (CRDS) inhibits human immunodeficiency virus (HIV)-1 infection, we examined its influence on the binding of gp120 to CD4 molecules on T cells and macrophages, as well as on the production of TNF-α by gp120-stimulated macrophages (which promotes HIV-1 replication). CRDS treatment of cells not only inhibited the binding of HIV-1 gp120 to CD4+ cells, but also inhibited TNF-α production induced by gp120. Inhibition of HIV-1 infection by CRDS may be related to these two actions.
著者
Naoki Yamamoto Eri Chatani
出版者
The Biophysical Society of Japan
雑誌
Biophysics and Physicobiology (ISSN:21894779)
巻号頁・発行日
vol.19, pp.e190017, 2022 (Released:2022-06-01)
参考文献数
34
被引用文献数
1

It is crucial to understand the mechanism of amyloid fibril formation for the development of the therapeutic ways against amyloidoses and neurodegenerative diseases. Prefibrillar intermediates, which emerge prior to the fibril formation, seem to play a key role to the occurrence of nuclei of amyloid fibrils. We have focused on an insulin-derived peptide, B chain, to precisely clarify the mechanism of the fibril formation via prefibrillar intermediates. Various kinds of methods such as circular dichroism spectroscopy, dynamic light scattering, small-angle X-ray scattering, and atomic force microscopy were employed to track the structural changes in prefibrillar intermediates. The prefibrillar intermediates possessing rod-shaped structures elongated as a function of time, which led to fibril formation. We have also found that a blood clotting protein, fibrinogen, inhibits the amyloid fibril formation of B chain. This was caused by the stabilization of prefibrillar intermediates and thus the suppression of their elongation by fibrinogen. These findings have not only shed light on detailed mechanisms about how prefibrillar intermediates convert to the amyloid fibril, but also demonstrated that inhibiting the structural development of prefibrillar intermediates is an effective strategy to develop therapeutic ways against amyloid-related diseases. This review article is an extended version of the Japanese article, Observing Development of Amyloid Prefibrillar Intermediates and their Interaction with Chaperones for Inhibiting the Fibril Formation, published in SEIBUTSU BUTSURI Vol. 61, p. 236–239 (2021).
著者
Ko NAKASUMI Naoki YAMAMOTO Taro TAKAMI Harumichi ITOH Kazuhito ITAMOTO Hiro HORIKIRIZONO Toshie ISERI Munekazu NAKAICHI Yuki NEMOTO Hiroshi SUNAHARA Kenji TANI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.84, no.1, pp.114-120, 2022 (Released:2022-01-13)
参考文献数
34
被引用文献数
3

Transcatheter arterial embolization (TAE) and transcatheter arterial chemoembolization (TACE) are standard treatments for advanced hepatocellular carcinoma (HCC) and particularly for unresectable tumors or liver metastases in humans. However, reports on TACE used in veterinary medicine are few. This study aimed to evaluate the feasibility and safety of drug-eluting bead transarterial chemoembolization (DEB-TACE). We performed DEB-TACE in four clinically normal dogs and pharmacokinetically compared the results against hepatic arterial infusion (HAI) of cisplatin in two dogs. Drug-eluting beads (DEB) loaded with cisplatin were injected through a microcatheter for selective embolization of the left hepatic artery. After embolization, computed tomography (CT) images and histological examination findings were obtained during a 4-week observation period. Serum platinum concentrations were measured to evaluate cisplatin after each procedure. Biochemical analysis was performed during a 12-week observation period. Embolization was successful in all dogs, and there were no clinically apparent abnormalities. Embolization was confirmed up to 4 weeks after DEB-TACE in two of the four dogs and up to 1 week in the other two dogs using postoperative CT images. Cisplatin was not detected in peripheral veins in all dogs after DEB-TACE, but it was detected in trace amounts after HAI. DEB-TACE using cisplatin was safe and well tolerated by normal dogs. DEB-TACE may be useful in terms of determining systemic toxicity and drug concentration within tumors.
著者
Naoki YAMAMOTO Momoka SHOJI Hiroki HOSHIGAMI Kohei WATANABE Kohei WATANABE Tappei TAKATSUZU Shin YASUDA Keiji IGOSHI Hideki KINOSHITA
出版者
BMFH Press
雑誌
Bioscience of Microbiota, Food and Health (ISSN:21863342)
巻号頁・発行日
vol.38, no.3, pp.97-104, 2019 (Released:2019-07-27)
参考文献数
61
被引用文献数
7 33

Reactive oxygen species (ROS), such as hydroxyl and superoxide anion radicals, are highly reactive molecules derived from the metabolism of oxygen. ROS play positive roles in cell physiology, but they may also damage cell membranes and DNA, inducing oxidation that causes membrane lipid peroxidation and decreases membrane fluidity. Soymilk yogurt, which is soymilk fermented using lactic acid bacteria (LAB), is an excellent food item with numerous functional substances with antioxidant effects. In this study, the antioxidative activities of soymilk yogurt were investigated. Sixteen of the 26 tested LAB strains solidified soymilk. In antioxidant capacity tests for bacterial cells, Leuconostoc mesenteroides MYU 60 and Pediococcus pentosaceus MYU 759 showed the highest values in the oxygen radical antioxidant capacity (ORAC) and hydroxyl radical antioxidant capacity (HORAC) tests, respectively. The supernatant of soymilk yogurt made with Lactobacillus gasseri MYU 1 showed the highest ORAC and HORAC values. L. mesenteroides MYU 60, Lactobacillus plantarum MYU 74, Lactobacillus reuteri MYU 220, and P. pentosaceus MYU 759 showed significantly high N-acetylcysteine equivalent values compared with the control in a total ROS reducing assay (p<0.05). These strains were selected, and a comet assay was performed, which exhibited decreased values in all selected strains compared with the control, indicating DNA protection. An acidic exopolysaccharide produced by P. pentosaceus MYU 759 showed high antioxidant capacity. The antioxidant substances produced by LAB fermentation may be exopolysaccharides, antioxidant peptides, and isoflavone aglycones. Soymilk yogurt can be used as a functional food useful for various diseases related to oxidation.
著者
Naoki Yamamoto Hiroyuki Kajiura Shinya Takeno Nobuaki Suzuki Yoshihisa Nakazawa
出版者
Japanese Society for Plant Cell and Molecular Biology
雑誌
Plant Biotechnology (ISSN:13424580)
巻号頁・発行日
pp.14.0609b, (Released:2014-08-23)
参考文献数
33
被引用文献数
1 3

We established a DNA watermarking system for discriminating transgenic plants. The system contains an encryption algorithm based on a binary system, genetic transformation and a detection algorithm for encrypted DNA watermark sequences using a DNA dot plot. The encryption algorithm converted character strings into nucleic acid sequences through binary digits, and the sequence was designed to be resistant to transition mutations to decipher codes completely. Moreover, the encrypted sequences were capable of taking specific nucleotide sequences in using the algorithmic redundancy of the corresponding DNA. Genetic transformation enables labeling plant genomes with DNA watermarks. The detection algorithm allows finding traces of sequence changes in DNA watermarks, complementing the error protection function of the encryption algorithm. To validate the effectiveness of our DNA watermarking system, we introduced a DNA watermark to the tobacco genome and detected the DNA watermark in PCR products amplified from the genome. This indicates that DNA watermark technology is useful for introducing artificial genetic markers in plant organisms, in particular when several transgenic host plants and transgenes are used. The source codes of the Perl scripts are available in this report.