研究者業績

矢口 貴志

ヤグチ タカシ  (Takashi Yaguchi)

基本情報

所属
千葉大学 真菌医学研究センター 准教授
学位
博士(工学)(早稲田大学)

J-GLOBAL ID
200901010374246864
researchmap会員ID
5000067659

論文

 264
  • Hidetaka Majima, Yuzaburo Inoue, Yuichiro Otsuka, Takashi Yaguchi, Akira Watanabe, Katsuhiko Kamei
    Medical mycology case reports 42 100609-100609 2023年12月  
    We hereby make the first report of a case of mycosis caused by Purpureocillium lilacinum in CARD9 deficiency. A 40-year-old woman complained of lymph node swellings in the left cervical area. She also had chronic mucocutaneous candidiasis (CMC), and was found to have CARD9 deficiency. Lymphadenitis by P. lilacinum was confirmed. The diagnosis was difficult, as culturing the biopsy specimen at a cautiously selected temperature (25 °C) and genetic analysis were both required. Oral administration of voriconazole improved her lymphadenopathy.
  • 井上 なつき, 伊藤 志昂, 矢口 貴志, 渡邉 哲, 亀井 克彦, 吉川 衛
    日本医真菌学会雑誌 64(Suppl.1) 98-98 2023年10月  
  • 井上 なつき, 伊藤 志昂, 矢口 貴志, 渡邉 哲, 亀井 克彦, 吉川 衛
    日本医真菌学会雑誌 64(Suppl.1) 98-98 2023年10月  
  • Isato Yoshioka, Yugo Mori, Ahmed Hassan Fahal, Emmanuel Edwar Siddig, Satoshi Kaneko, Takashi Yaguchi
    PLoS neglected tropical diseases 17(9) e0011644 2023年9月18日  
    BACKGROUND: Filamentous fungi of the genus Madurella are the primary causative agents of mycetoma, a disease observed in tropical and subtropical regions. Since early diagnostics based on a morphological approach are difficult and have many shortcomings, a molecular diagnostic method suitable for rural settings is required. In this study, we developed the loop-mediated isothermal amplification (LAMP) method to present a foundational technique of the diagnosis of Madurella spp. (M. mycetomatis, M. pseudomycetomatis, M. tropicana, and M. fahalii), the common causative organisms of eumycetoma. PRINCIPAL FINDINGS: We successfully designed a primer pair targeting the rDNAs of three Madurella spp. excluding M. fahalii, and detected up to 100 fg of genomic DNA extracted from isolates of M. mycetomatis and 1 pg of M. pseudomycetomatis and M. tropicana, within one hour. Second, a primer pair specific to M. mycetomatis, the most common causative species, or M. fahalii, a drug-resistant species, was constructed, and the detection limit of both primer pairs was 1 pg. The designed primers accurately distinguished 16 strains of the genus Madurella from various fungal species known to cause mycetomas. CONCLUSION: In summary, we established the first model of a LAMP detection method that rapidly and sensitively detects and identifies Madurella isolates for clinical diagnostics. Moreover, the combined designed primer sets could identify mycetoma-causing strains simultaneously.
  • Sara Higuchi, Hiromitsu Noguchi, Tadahiko Matsumoto, Takashi Yaguchi, Masahide Kubo, Kayo Kashiwada-Nakamura, Masataro Hiruma, Rui Kano, Takahiro Satoh, Satoshi Fukushima
    Mycopathologia 2023年7月26日  
  • Yuri Ogura, Takashi Yaguchi, Yu Kasamatsu, Yuta Nakagawa, Tomomi Yamada, Ayano Maruyama, Aya Miyagawa-Hayashino, Koichi Takayama, Kazutoshi Shibuya, Hiroshi Kakeya, Katsuhiko Kamei
    Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy 2023年6月5日  
    Blastomycosis is a fungal infectious disease that can occur in both immunocompromised and immunocompetent populations endemic in North America, with no previous reports in Japan. A 26-year-old Japanese female patient with no relevant medical history presented intermittent left back pain and an abnormal shadow in the left upper lung field eight months ago at a local clinic. She was referred to our hospital for further evaluation and treatment. The patient currently lives in Japan, but until two years ago had spent several years in New York, Vermont and California. Chest computed tomography revealed a 30 mm mass with a cavity in the left pulmonary apex. The specimens obtained by transbronchial biopsy showed periodic acid-Schiff stain (PAS)-positive and Grocott-positive yeast-like fungi scattered among the granulomas, with no malignant findings, and the initial pathology did not lead to a definitive diagnosis. She was empirically started on fluconazole because of onset of multiple subcutaneous abscesses and was referred to the Medical Mycology Research Center. Although antibody tests could not diagnose the disease, blastomycosis was suspected based on the pathology of the skin and lung tissue at the Medical Mycology Research Center, and Blastomyces dermatitidis was identified by ITS analysis of the rRNA region. Her symptoms and CT findings gradually improved with fluconazole. We reported the first Japanese case of blastomycosis with pulmonary and cutaneous involvement in Japan. As the number of overseas travelers is expected to continue increasing, we would like to emphasize the importance of travel history interviews and information of blastomycosis.
  • Isato Yoshioka, Hiroki Takahashi, Yoko Kusuya, Takashi Yaguchi, Akira Shibata, Kohtaro Kirimura
    Microbiology resource announcements e0109322 2023年1月4日  
    Aspergillus lacticoffeatus WU-2020 is a citric acid hyperproducer that is suitable for solid culture. Here, we present a high-quality draft of its genome sequence (35.9 Mb), which consists of 11 scaffolds and contains 11,490 genes. We also present the mitochondrial genome, which is 31.3 kb in length.
  • Sara Higuchi, Hiromitsu Noguchi, Tadahiko Matsumoto, Kayo Kashiwada-Nakamura, Masahide Kubo, Rui Kano, Takashi Yaguchi, Takahiro Satoh, Satoshi Fukushima
    The Journal of dermatology 50(5) e162-e163 2022年12月22日  
  • Takayuki Ishibashi, Chika Ichimura, Masahide Kubo, Hiromitsu Noguchi, Tadahiko Matsumoto, Rui Kano, Takashi Yaguchi, Satoshi Fukushima
    Mycopathologia 188(3) 259-262 2022年11月21日  
  • Hiromitsu Noguchi, Tadahiko Matsumoto, Masahide Kubo, Utako Kimura, Masataro Hiruma, Takashi Yaguchi, Tsuyoshi Yamada, Rui Kano
    The Journal of Dermatology 49(11) 2022年11月  
  • 渡辺 駿介, 宮本 菜夕利, 永野 雄二, 猪野 晋慶, 野瀬 和彦, 亀井 克彦, 矢口 貴志
    首都圏支部・関甲信支部医学検査学会プログラム・講演抄録集 58回 86-86 2022年10月  
  • Kayo Kashiwada-Nakamura, Hiromitsu Noguchi, Masataro Hiruma, Masaru Tanaka, Takashi Yaguchi, Yudo Kusaba, Azusa Miyashita, Hideyuki Hayashi, Satoshi Fukushima
    The Journal of dermatology 49(12) e449-e450 2022年8月19日  
  • Hiromitsu Noguchi, Tadahiko Matsumoto, Masahide Kubo, Utako Kimura, Masataro Hiruma, Masaru Tanaka, Takashi Yaguchi, Tsuyoshi Yamada, Rui Kano
    Mycopathologia 187(4) 421-422 2022年8月  
  • Yasumasa Hara, Keiichiro Watanabe, Akiko Takaya, Teruhisa Manome, Takashi Yaguchi, Masami Ishibashi
    Organic Letters 24(27) 4998-5002 2022年7月6日  
  • C. Bian, Y. Kusuya, F. Sklenář, E. D'hooge, T. Yaguchi, S. Ban, C.M. Visagie, J. Houbraken, H. Takahashi, V. Hubka
    Studies in Mycology 102(1) 95-132 2022年6月30日  
    The Aspergillus series Nigri contains biotechnologically and medically important species. They can produce hazardous mycotoxins, which is relevant due to the frequent occurrence of these species on foodstuffs and in the indoor environment. The taxonomy of the series has undergone numerous rearrangements, and currently, there are 14 species accepted in the series, most of which are considered cryptic. Species-level identifications are, however, problematic or impossible for many isolates even when using DNA sequencing or MALDI-TOF mass spectrometry, indicating a possible problem in the definition of species limits or the presence of undescribed species diversity. To re-examine the species boundaries, we collected DNA sequences from three phylogenetic markers (benA, CaM and RPB2) for 276 strains from series Nigri and generated 18 new whole-genome sequences. With the three- gene dataset, we employed phylogenetic methods based on the multispecies coalescence model, including four single-locus methods (GMYC, bGMYC, PTP and bPTP) and one multilocus method (STACEY). From a total of 15 methods and their various settings, 11 supported the recognition of only three species corresponding to the three main phylogenetic lineages: A. niger, A. tubingensis and A. brasiliensis. Similarly, recognition of these three species was supported by the GCPSR approach (Genealogical Concordance Phylogenetic Species Recognition) and analysis in DELINEATE software. We also showed that the phylogeny based on benA, CaM and RPB2 is suboptimal and displays significant differences from a phylogeny constructed using 5 752 single-copy orthologous proteins; therefore, the results of the delimitation methods may be subject to a higher than usual level of uncertainty. To overcome this, we randomly selected 200 genes from these genomes and performed ten independent STACEY analyses, each with 20 genes. All analyses supported the recognition of only one species in the A. niger and A. brasiliensis lineages, while one to four species were inconsistently delimited in the A. tubingensis lineage. After considering all of these results and their practical implications, we propose that the revised series Nigri includes six species: A. brasiliensis, A. eucalypticola, A. luchuensis (syn . A. piperis), A. niger (syn. A. vinaceus and A. welwitschiae), A. tubingensis (syn. A. chiangmaiensis, A. costaricensis, A. neoniger and A. pseudopiperis) and A. vadensis. We also showed that the intraspecific genetic variability in the redefined A. niger and A. tubingensis does not deviate from that commonly found in other aspergilli. We supplemented the study with a list of accepted species, synonyms and unresolved names, some of which may threaten the stability of the current taxonomy.
  • Yoshitsugu Inoue, Yuichi Ohashi, Yoshikazu Shimomura, Chie Sotozono, Hiroshi Hatano, Masahiko Fukuda, Hiroshi Eguchi, Kaoru Araki-Sasaki, Takashi Suzuki, Saichi Hoshi, Seishi Asari, Atsuko Sunada, Keigo Kimura, Takashi Yaguchi, Koichi Makimura
    Japanese journal of ophthalmology 66(3) 227-239 2022年5月  
    PURPOSE: To investigate the clinical characteristics and causative fungi in patients with fungal keratitis in Japan, and to determine factors related to the prognosis. STUDY DESIGN: Multicenter prospective observational study. METHODS: Eligible patients were enrolled from November 2011 to October 2013 at the 1st stage and from April 2015 to March 2016 at the 2nd stage. The corneal foci were scraped, and the scrapings were cultured in potato dextrose agar. The isolated fungi were identified by gene analyses. Data were collected from the clinical records and statistically analyzed by Cox and logistic regression analyses. RESULTS: Ninety-four fungal strains were isolated from 93 cases, including 42 yeast-like fungi and 52 filamentous fungi. The fungi affected the deep layers of the cornea in 23 cases (24.7%) and the peripheral cornea in 29 cases (31.2%). The incidences of lid swelling/redness, ciliary injection, anterior chamber cells/flare, anterior chamber fibrin, and hyphate ulcer in cases of filamentous fungi were significantly higher than in yeast-like fungi. No history of topical steroids, absence of a main lesion in the peripheral cornea, and best-corrected visual acuity (BCVA) of more than 0.04 at the first visit were related to a shorter healing time. No history of ocular surgery, absence of lesion at one-third deep stromal layer and BCVA of more than 0.04 at the first visit were correlated with BCVA at 3 months after the initial examination. CONCLUSION: Fungal keratitis is caused by various species of fungi and can become refractory due to poor prognosis factors.
  • Keigo Kimura, Yoshitsugu Inoue, Seishi Asari, Atsuko Sunada, Yuichi Ohashi, Yoshikazu Shimomura, Chie Sotozono, Hiroshi Hatano, Masahiko Fukuda, Hiroshi Eguchi, Kaoru Araki-Sasaki, Takashi Suzuki, Saichi Hoshi, Toru Tobe, Takashi Yaguchi, Koichi Makimura
    Japanese journal of ophthalmology 66(3) 240-253 2022年5月  
    PURPOSE: To determine the effects of a combination of two antifungal drugs against causative fungi of fungal keratitis in Japan. STUDY DESIGN: Multicenter prospective observational study. METHODS: Eighteen isolates of yeast-like fungi and 22 isolates of filamentous fungi collected by the Multicenter Prospective Observational Study of Fungal Keratitis in Japan were studied. Specially manufactured minimum inhibitory concentration (MIC) measurement plates were used to test the effectiveness of 10 combinations of two antifungal drugs against the isolates. The combinations were pimaricin (PMR) + voriconazole (VRCZ), PMR + fluconazole (FLCZ), PMR + miconazole (MCZ), PMR + micafungin (MCFG), VRCZ + FLCZ, VRCZ + MCZ, VRCZ + MCFG, VRCZ + amphotericin-B (AMPH-B), MCZ + FLCZ, and MCZ + MCFG. The checkerboard microdilution method was used, and the fractional inhibitory concentration (FIC) index was calculated based on the guidelines of The Clinical & Laboratory Standards Institute (CLSI). RESULTS: In yeast-like fungi, additive effects were observed between PMR and MCFG in 77.8% of the isolates, and they were also observed between the azoles. Synergistic effects were observed on 11.1% of the isolates for MCZ and FLCZ. On the other hand, antagonistic effects were present between PMR and azoles with 88.9% between PMR and VRCZ, 72.2% between PMR and FLCZ, and 94.4% between PMR and MCZ. In filamentous fungi, additive effects were observed between PMR and MCFG in 40.9% of the isolates, and between VRCZ and MCZ in 40.9% of the isolates. Antagonistic effects were observed for PMR and the azoles. CONCLUSIONS: The combination of drugs prescribed for fungal keratitis incurs a possibility of synergistic, additive, indifferent, or antagonistic effects, depending on drug combinations and fungal strains.
  • Kazuki Ishikawa, Masaki Ishii, Takashi Yaguchi, Toshiaki Katada, Koji Ichinose, Shinya Ohata
    Biochemical and biophysical research communications 596 104-110 2022年3月12日  
    Nuclear factor-kappa B (NF-κB) signaling is an intracellular signaling pathway involved in inflammatory responses and the pathogenesis of various cancers, including ependymoma, which is a rare and chemotherapy-resistant glioma. Several isoforms of fusion proteins that consist of a nuclear protein, zinc finger translocation associated (ZFTA), and RELA (ZFTA-RELA), an NF-κB-signaling effector transcription factor, cause excessive activation of the NF-κB signaling pathway and result in supratentorial ependymomas (ST-EPN-RELA). As inhibitors of NF-κB activity induced by ZFTA-RELA are expected to be therapeutic agents for ST-EPN-RELA, we established an NF-κB responsive luciferase reporter cell line that expresses the most common isoform of ZFTA-RELA in a doxycycline-dependent manner. Using this reporter cell line, we screened fungus extracts for compounds that inhibit the NF-κB activity induced by ZFTA-RELA expression and identified aszonalenin, an alkaloid from Aspergillus novofumigatus. We also purified analogs of aszonalenin, namely acetylaszonalenin and epi-aszonalenin B and C. In a luciferase assay using cells constitutively expressing luciferase (counter assay), acetylaszonalenin and epi-aszonalenin C showed non-specific inhibition of the luciferase activity. Aszonalenin and epi-aszonalenin B inhibited the NF-κB responsive luciferase activity by expressing ZFTA-RELA more strongly than the luciferase activity in the counter assay. The upregulation of endogenous NF-κB responsive genes, such as CCND1, ICAM1, and L1CAM, by ZFTA-RELA expression was inhibited by epi-aszonalenin B, but not by aszonalenin. This study suggests that epi-aszonalenin B may be a lead compound for the therapeutic development of ST-EPN-RELA.
  • Hiromitsu Noguchi, Tadahiko Matsumoto, Utako Kimura, Masataro Hiruma, Rui Kano, Takashi Yaguchi, Masahide Kubo, Kayo Kashiwada-Nakamura, Satoshi Fukushima
    The Journal of dermatology 49(5) 564-571 2022年2月25日  
    We encountered two cases of phaeohyphomycosis caused by Exophiala jeanselmei and E. oligosperma that were treated with fosravuconazole and terbinafine, respectively. Our cases were successfully treated with empiric therapy before the pathogen's species or antifungal sensitivity had been determined. We summarized 32 cases of cutaneous and subcutaneous phaeohyphomycosis caused by Exophiala species in Japan. The patients received antifungals, including itraconazole, terbinafine, voriconazole, and fosravuconazole, and the treatment success rates of these monotherapies were 77% (17/22), 67% (8/12), 100% (5/5), and 50% (1/2), respectively. Although the broad-spectrum azole antifungal itraconazole is the first choice for treatment, terbinafine at 125 mg/day might exert the same efficacy. Fosravuconazole is a novel broad-spectrum azole and a moderate inhibitor of Cyp3A4 that causes fewer drug interactions than itraconazole and voriconazole, indicating a promising drug for this disease.
  • Yikelamu Alimu, Sayaka Ban, Takashi Yaguchi
    Medical mycology journal 63(1) 1-9 2022年  
    In this study, we aimed to clarify the phylogenetic distribution of Exophiala dermatitidis in Japan and describe the characteristics of genotypes. We examined 67 clinical and environmental isolates that were morphologically identified and preserved as E. dermatitidis and we confirmed the identification on the basis of the ribosomal DNA internal transcribed spacer region. Genotype sequences were aligned and compared using maximum likelihood phylogenetic tree analyses of the ITS1 region. Additionally, the strains of each genotype were tested for mycological characteristics, such as growth temperature, growth rate, and drug sensitivity. The 67 strains examined were isolated from Japan, the United States, Brazil, Venezuela, and China. In accordance with the establishment of a phylogenetic tree for the ITS1 region, 45 of the 49 Japanese strains were classified as genotype A, two as genotype B, and two as genotype D (A2 according to the method of Matos et al. (2003)). Chinese strains were divided into genotypes A and D (A2), and South American strains were classified into genotypes A, B, B2, and C2, while all strains from the U.S. belonged to genotype A. New genotype groups B2 and C2 were identified in Brazilian and Venezuelan strains, respectively. There were no specific differences among the genotypes or isolated regions in the antifungal susceptibility test for all E. dermatitidis isolates. However, genotypes B2 and D (A2) exhibited growth at higher temperatures than the other genotypes.
  • Yikelamu Alimu, Yoko Kusuya, Takako Yamamoto, Kana Arita, Naofumi Shigemune, Hiroki Takahashi, Takashi Yaguchi
    Biocontrol science 27(3) 117-130 2022年  
    Purpureocillium lilacinum has been recently found to contaminate a 20% (200,000 μg/mL) aqueous solution of polyhexamethylene biguanide hydrochloride (PHMB) . We aimed to elucidate the mechanism underlying the resistance of P. lilacinum to PHMB. First, we induced the PHMB-resistant (IR) strains IFM 67050 (IR) and IFM 65838 (IR) from the type strain P. lilacinum CBS 284.36T via cultivation in a medium containing high concentrations of PHMB. We then analyzed the DNA sequences via Illumina sequencing to evaluate the presence of genetic mutations in IFM 65838 (IR) . Further, we established an IFM 65838 (IR) uridine/uracil auxotrophic strain, and using the orotidine-5'-decarboxylase gene, pyrG as a selection marker, we tried to knockout a mutant gene in IFM 65838 (IR) using the CRISPR-Cas9 genome-editing technique. The growth rates of IFM 67050 (IR) and IFM 65838 (IR) in medium containing PHMB increased, and the minimum inhibitory concentrations (MICs) against PHMB also increased. Based on the DNA sequence analysis, we found a nonsynonymous point mutation in the gene PLI-008146 (G779A) in IFM 67050 (IR) and IFM 65838 (IR) . This point mutation leads to site combinations of splicing changes that cause partial sequences deletion (p.Y251_G281del) in the ΔPLI-008146 locus of IFM 65838 (IR) , and deletion sequences include partial adenosine/AMP deaminase motif (PF00962) orthologous to adenosine deaminase (ADA) (GeneBank: OAQ82383.1) . Furthermore, the mutant gene ΔPLI-008146 was successfully knocked out from the resistanceinduced strain using a novel CRISPR-Cas9 gene transformation method. A considerable reduction in growth rate and MIC against PHMB was observed in the absence of the mutant gene. Therefore, ADA may represent an important resistance factor in PHMB-resistant P. lilacinum.
  • Hiromitsu Noguchi, Tadahiko Matsumoto, Utako Kimura, Masataro Hiruma, Rui Kano, Takashi Yaguchi, Kayo Kashiwada-Nakamura, Satoshi Fukushima
    The Journal of dermatology 49(1) e38-e39 2022年1月  
  • Rui Kano, Kazuo Satoh, Takashi Yaguchi, Michiaki Masuda, Koichi Makimura, G Sybren de Hoog
    Medical mycology journal 63(1) 17-20 2022年  
    The genus Prototheca consists of achlorophyllic algae that are ubiquitous in the environment and also occur in animal intestines; occasionally, infections in humans and animals are observed. In this study, we conducted tests of assimilative abilities and thermotolerance in comparison with morphological characteristics of six opportunistic species (Prototheca blaschkeae, Prototheca bovis, Prototheca ciferrii, Prototheca cutis, Prototheca miyajii, and Prototheca wickerhamii) along with Prototheca paracutis. Five of the seven species could be differentiated by physiological characteristics, but P. wickerhamii and P. cutis had identical profiles. Of the cattle-associated species, only P. bovis was able to grow at 42°C. Both type strains of P. cutis and P. miyajii were most susceptible to ravuconazole compared with the other azoles.
  • Sayoko Oiki, Takashi Yaguchi, Syun-Ichi Urayama, Daisuke Hagiwara
    PloS one 17(1) e0262521 2022年  
    Fludioxonil and iprodione are effective fungicides widely used for crop protection and are essential for controlling plant pathogenic fungi. The emergence of fungicide-resistant strains of targeted pathogens is regularly monitored, and several cases have been reported. Non-targeted fungi may also be exposed to the fungicide residues in agricultural fields. However, there are no comprehensive reports on fungicide-resistant strains of non-targeted fungi. Here, we surveyed 99 strains, representing 12 Penicillium species, that were isolated from a variety of environments, including foods, dead bodies, and clinical samples. Among the Penicillium strains, including non-pathogenic P. chrysogenum and P. camembertii, as well as postharvest pathogens P. expansum and P. digitatum, 14 and 20 showed resistance to fludioxonil and iprodione, respectively, and 6 showed multi-drug resistance to the fungicides. Sequence analyses revealed that some strains of P. chrysogenum and Penicillium oxalicum had mutations in NikA, a group III histidine kinase of the high-osmolarity glycerol pathway, which is the mode of action for fludioxonil and iprodione. The single nucleotide polymorphisms of G693D and T1318P in P. chrysogenum and T960S in P. oxalicum were only present in the fludioxonil- or iprodione-resistant strains. These strains also exhibited resistance to pyrrolnitrin, which is the lead compound in fludioxonil and is naturally produced by some Pseudomonas species. This study demonstrated that non-targeted Penicillium strains distributed throughout the environment possess fungicide resistance.
  • Yasumasa Hara, Masami Ishibashi, Daiki Tanimura, Teruhisa Manome, Midori A. Arai, Takashi Yaguchi
    HETEROCYCLES 104(1) 185-185 2022年  
  • Hazim O Khalifa, Vit Hubka, Akira Watanabe, Minoru Nagi, Yoshitsugu Miyazaki, Takashi Yaguchi, Katsuhiko Kamei
    Antimicrobial agents and chemotherapy 66(2) AAC0185621 2021年12月6日  
    This study was designed to evaluate the prevalence of antifungal resistance, genetic mechanisms associated with in vitro induction of azole and echinocandin resistance and genotyping of Candida krusei, which is intrinsically resistant to fluconazole and is recovered from clinical and non-clinical sources from different countries. Our results indicated that all the isolates were susceptible or had the wild phenotype (WT) to azoles, amphotericin B, and only 1.27% showed non-WT for flucytosine. Although 70.88% of the isolates were resistant to caspofungin, none of them were categorized as echinocandin-resistant as all were susceptible to micafungin and no FKS1 hotspot 1 (HS1) or HS2 mutations were detected. In vitro induction of azole and echinocandin resistance confirmed the rapid development of resistance at low concentrations of fluconazole (4 μg/ml), voriconazole (0.06 μg/ml) and micafungin (0.03 μg/ml), with no difference between clinical and non-clinical isolates in the resistance development. Overexpression of ABC1 gene and FKS1 HS1 mutations were the major mechanisms responsible for azole and echinocandin resistance, respectively. Genotyping of our 79 isolates coupled with 217 other isolates from different sources and geography confirmed that the isolates belong to two main subpopulations, with isolates from human clinical material and Asia being more predominant in cluster 1, and environmental and animals isolates and those from Europe in cluster 2. Our results are of critical concern, since realizing that the C. krusei resistance mechanisms and their genotyping are crucial for guiding specific therapy and for exploring the potential infection source.
  • Hiromitsu Noguchi, Tadahiko Matsumoto, Utako Kimura, Masataro Hiruma, Rui Kano, Takashi Yaguchi, Kayo Kashiwada-Nakamura, Satoshi Fukushima
    The Journal of dermatology 48(12) e608-e609 2021年12月  
  • 齊藤 匠吾, 三浦 采香, 倉田 一男, 亀井 克彦, 矢口 貴志, 四元 周
    日臨技北日本支部医学検査学会抄録集 9回 7-7 2021年11月  
  • 齊藤 匠吾, 三浦 采香, 倉田 一男, 亀井 克彦, 矢口 貴志, 四元 周
    日臨技北日本支部医学検査学会抄録集 9回 7-7 2021年11月  
  • Chie Watanabe, Yoshifumi Kimizuka, Yuji Fujikura, Takaaki Hamamoto, Akira Watanabe, Takashi Yaguchi, Tomoya Sano, Ryohei Suematsu, Yoshiki Kato, Jun Miyata, Susumu Matsukuma, Akihiko Kawana
    Internal medicine (Tokyo, Japan) 2021年10月26日  
    A 69-year-old woman who had undergone renal transplantation and was receiving sulfamethoxazole/trimethoprim (ST) developed pulmonary nocardiosis. To our knowledge, this is the first report of the identification of Nocardia elegans using nanopore sequencing, supported by 16S rDNA capillary sequencing findings. Chest computed tomography performed after ST initiation revealed significant improvement of the pulmonary shadows compared to previous findings. We herein report the value of nanopore sequencing for rapid identification of rare pathogens, such as Nocardia elegans. Furthermore, our findings suggest that Nocardia may infect even patients receiving ST, which is currently the most effective prophylactic drug.
  • Naoya Itoh, Nana Akazawa, Hiromi Murakami, Yuichi Ishibana, Yusuke Takahashi, Waki Hosoda, Takashi Yaguchi, Katsuhiko Kamei
    BMC infectious diseases 21(1) 1052-1052 2021年10月9日  
    BACKGROUND: Schizophyllum commune is a basidiomycete that lives in the environment and can cause infections, mainly those of the respiratory system. Although S. commune is increasingly reported as a cause of allergic bronchopulmonary mycosis and sinusitis, cases of fungal ball formation are extremely uncommon. Identification of S. commune is difficult using routine mycological diagnostic methods, and in clinically suspicious cases, internal transcribed spacer sequencing should be used for diagnosis. Here, we report a first case of lung cancer with a fungal ball formation of S. commune, confirmed by analyzing the internal transcribed spacer. CASE PRESENTATION: A 76-year-old man with diabetes and hypertension was admitted to the hospital with a chief complaint of hemosputum, which he had for about 19 months. A computed tomography image of the patient's chest showed a cavity and internal nodule in the left upper lobe of his lung. A left upper lobectomy was performed, and histopathological examination revealed squamous cell carcinoma of the lung and a fungal ball. The isolate from the surgical specimen was identified as S. commune by analyzing the internal transcribed spacer. The patient had no recurrence of the infection during 5 months of follow-up. CONCLUSIONS: Only three cases of lung fungal balls caused by S. commune have been previously reported, and this is the first case of lung cancer cavity with a fungal ball formation. In cases of fungal ball formation in the lung, S. commune should be considered a possible causative microorganism.
  • 馬嶋 秀考, 新居 鉄平, 楠屋 陽子, 高橋 弘喜, 渡邉 哲, 矢口 貴志, 宮崎 泰成, 亀井 克彦
    日本医真菌学会雑誌 62(Suppl.1) 100-100 2021年10月  
  • Hiromitsu Noguchi, Tadahiko Matsumoto, Masataro Hiruma, Utako Kimura, Kayo Kashiwada-Nakamura, Masahide Kubo, Takashi Yaguchi, Satoshi Fukushima, Rui Kano
    Acta dermato-venereologica 101(9) adv00563 2021年9月28日  
  • 中村 文香, 原 康雅, 高屋 明子, 矢口 貴志, 石橋 正己
    日本生薬学会年会講演要旨集 67回 239-239 2021年8月  
  • Yurie Kitauchi, Yoshiko Kumagai, Yoko Inoue-Masuda, Makoto Sugiura, Tomotaka Sato, Takashi Yaguchi, Tomoaki Yokoyama
    The Journal of dermatology 48(7) e329-e330 2021年7月  
  • Kayo Kashiwada-Nakamura, Hiromitsu Noguchi, Tadahiko Matsumoto, Takashi Yaguchi, Katsuhiko Kamei, Takahisa Suzuki, Takamitsu Makino, Ikko Kajihara, Satoshi Fukushima, Hironobu Ihn
    The Journal of dermatology 48(5) e234-e235 2021年5月  
  • Naoya Itoh, Hiromi Murakami, Yuichi Ishibana, Yuki Matsubara, Takashi Yaguchi, Katsuhiko Kamei
    Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy 2021年4月19日  
    BACKGROUND: Exophiala (Wangiella) dermatitidis is a clinically relevant black yeast. Although E. dermatitidis rarely causes human infection, it can cause superficial and deep-seated infections, and cutaneous and subcutaneous diseases. Cases of fungemia and central line-associated bloodstream infections due to E. dermatitidis are extremely uncommon, and their clinical manifestations and prognosis are still not well-known. Herein, we report a case of central line-associated bloodstream infections in a patient with cancer. These infections were caused by melanized yeast that was finally identified as E. dermatitidis via internal transcribed spacer sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. CASE PRESENTATION: A 75-year-old man with thoracic esophageal cancer and early gastric cancer presented with a 1-day history of fever during his hospitalization at our hospital. A central venous port was placed in the patient for total parenteral nutrition. Two E. dermatitidis isolates were recovered from two blood samples drawn at different times from a peripheral vein and this central venous port. The isolate was identified as E. dermatitidis by internal transcribed spacer sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The central venous port was removed, and the patient was administered micafungin and voriconazole. Although the minimum inhibitory concentrations of E. dermatitidis for voriconazole and minimum effective concentrations for micafungin were 2 μg/mL and 4 μg/m, respectively, the bacteremia was successfully treated. CONCLUSIONS: Although no clear treatment guidelines have been proposed for E. dermatitidis infections, immediate removal of central venous catheters is the key to improving central line-associated bloodstream infections.
  • Hiroki Takahashi, Maiko Umemura, Akihiro Ninomiya, Yoko Kusuya, Masaaki Shimizu, Syun-ichi Urayama, Akira Watanabe, Katsuhiko Kamei, Takashi Yaguchi, Daisuke Hagiwara
    Frontiers in Fungal Biology 2 2021年4月16日  
    Filamentous fungi produce various bioactive compounds that are biosynthesized by sets of proteins encoded in biosynthesis gene clusters (BGCs). For an unknown reason, many BGCs are transcriptionally silent in laboratory conditions, which has hampered the discovery of novel fungal compounds. The transcriptional reactiveness of fungal secondary metabolism is not fully understood. To gain the comprehensive view, we conducted comparative genomic and transcriptomic analyses of nine closely-related species of <italic>Aspergillus</italic> section <italic>Fumigati</italic> (<italic>A. fumigatus, A. fumigatiaffinis, A. novofumigatus, A. thermomutatus, A. viridinutans, A. pseudoviridinutans, A. lentulus, A. udagawae</italic>, and <italic>Neosartorya fischeri</italic>). For expanding our knowledge, we newly sequenced genomes of <italic>A. viridinutans</italic> and <italic>A. pseudoviridinutans</italic>, and reassembled and reannotated the previously released genomes of <italic>A. lentulus</italic> and <italic>A. udagawae</italic>. Between 34 and 84 secondary metabolite (SM) backbone genes were identified in the genomes of these nine respective species, with 8.7–51.2% being unique to the species. A total of 247 SM backbone gene types were identified in the nine fungi. Ten BGCs are shared by all nine species. Transcriptomic analysis using <italic>A. fumigatus, A. lentulus, A. udagawae, A. viridinutans</italic>, and <italic>N. fischeri</italic> was conducted to compare expression levels of all SM backbone genes in four different culture conditions; 32–83% of SM backbone genes in these species were not expressed in the tested conditions, which reconfirmed that large part of fungal SM genes are hard to be expressed. The species-unique SM genes of the five species were expressed with lower frequency (18.8% in total) than the SM genes that are conserved in all five species (56%). These results suggest that the expression tendency of BGCs is correlated with their interspecies distribution pattern. Our findings increase understanding of the evolutionary processes associated with the regulation of fungal secondary metabolism.
  • Midori A. Arai, Itsuki Ebihara, Yoshinori Makita, Yasumasa Hara, Takashi Yaguchi, Masami Ishibashi
    The Journal of Antibiotics 74(4) 255-259 2021年4月  
  • Tomohiro Suzuki, Tomotaka Sato, Akiko Kasuya, Takashi Yaguchi
    Medical mycology journal 62(1) 1-4 2021年  
    We present a 76-year-old Japanese male with tinea faciei, tinea corporis, and tinea unguium with dermatophytoma. We performed fungal culture and confirmed the causative fungus to be Trichophyton rubrum. We treated the patient using oral fosravuconazole l-lysine ethanolate (F-RVCZ). More than one year has passed since the end of treatment, but there has been no recurrence. This case suggests that F-RVCZ is effective for tinea other than tinea unguium.
  • Tomohiro Suzuki, Tomotaka Sato, Hiroto Horikawa, Akiko Kasuya, Takashi Yaguchi
    Medical mycology journal 62(4) 67-70 2021年  
    Tinea imbricata and tinea pseudoimbricata are variant types of tinea corporis characterized by annual-ring-shaped erythema. Although the skin lesions manifest similar symptoms, these two diseases are classified based on causative fungi. The former is caused by Trichophyton concentricum, an anthropophilic dermatophyte, and the latter is caused by dermatophytes other than T. concentricum, commonly zoophilic fungi such as Trichophyton mentagrophytes complex. Here, we report a 27-year-old Japanese male diagnosed with tinea pseudoimbricata attributed to Trichophyton tonsurans, an anthropophilic dermatophyte. We suspected that application of steroid ointment caused the annular pattern of his skin lesions. After three months use of topical luliconazole cream, treatment was finished. We also summarize the knowledge about tinea pseudoimbricata through previous reports with bibliographical consideration.
  • Tomotaka Sato, Akiko Kasuya, Hisashi Kobayashi, Yasuhiko Asahina, Tomohiro Suzuki, Kazuhiro Aoyama, Kazuto Yamazaki, Takashi Yaguchi
    Medical mycology journal 62(4) 89-92 2021年  
    A 57-year-old male patient with >10-year history of type 2 diabetes presented with a left big toenail deformity and pain. A physical examination revealed a white and yellow-to-brown patch on the nail as well as thickening and ingrowth of the nail plate. The nail plate was opened using nippers, and a fungal culture revealed Trichophyton interdigitale with yellow yeast. The yeast isolate was identified as Kocuria koreensis, a Gram-positive aerobic coccoid with keratinolytic properties that is part of the normal flora of the skin. We created an ex vivo onychomycosis model of T. interdigitale infection of the human nail by placing a sterilized normal nail on the cultured slant. K. koreensis initially spread over the normal nail, and T. interdigitale then penetrated the nail plate. After one year and six months, a spiral ingrown nail developed. A histopathological examination of the spiral revealed onychomycosis with superficial and deep abscesses of Gram-positive cocci infection. We performed PCR from paraffin-embedded material, and the sequences obtained were identical to those of T. interdigitale and K. koreensis. These results suggest that the development of onychomycosis by T. interdigitale is introduced and accelerated by K. koreensis, and the symbiosis of these microorganisms is suspected in the nail. This ex vivo model has a number of limitations. Therefore, further research on co-infected cases is needed to confirm this hypothesis.
  • Takako Yamamoto, Yikelamu Alimu, Hiroki Takahashi, Yoko Kusuya, Kouichi Hosoya, Naofumi Shigemune, Satoshi Nagai, Takashi Yaguchi
    Biocontrol science 26(3) 157-166 2021年  
    We isolated a fungus from a 20% (= 200,000 µg/mL) aqueous solution of polyhexamethylene biguanide hydrochloride (PHMB), a widely used antimicrobial and examined its morphology and drug resistance profile. Based on the sequence of the internal transcribed spacer region of ribosomal DNA, the fungus was identified as Purpureocillium lilacinum. Although the P. lilacinum type and resistant strains showed similar morphology, the latter had extremely low PHMB susceptibility and was able to grow in 20% aqueous solution of PHMB, which eliminated the type strain. The minimum inhibitory concentration (MIC) of PHMB for the resistant strain was significantly higher than that of the type strain and other pathogenic filamentous fungi and yeasts. The susceptibility to antimicrobial agents and antifungal agents other than PHMB was similar to that of the type strain, therefore the drug resistance of the isolate was specific to PHMB. Furthermore, we sequenced the genome of the isolate to predict PHMB resistance-related genes. Despite its high resistance to PHMB, no well-known genes homologous to fungal PHMB-resistant genes were detected in the genome of the resistant strain. In summary, P. lilacinum was found to be significantly more resistant to PHMB than previously reported, via an unidentified mechanism of drug resistance.
  • Yuto Chiba, Sayoko Oiki, Takashi Yaguchi, Syun-Ichi Urayama, Daisuke Hagiwara
    Virus evolution 7(1) veab027 2021年1月  
    [This corrects the article DOI: 10.1093/ve/veaa101.].
  • Yuto Chiba, Sayoko Oiki, Takashi Yaguchi, Syun-Ichi Urayama, Daisuke Hagiwara
    Virus evolution 7(1) veaa101 2021年1月  
    By identifying variations in viral RNA genomes, cutting-edge metagenome technology has potential to reshape current concepts about the evolution of RNA viruses. This technology, however, cannot process low-homology genomic regions properly, leaving the true diversity of RNA viruses unappreciated. To overcome this technological limitation, we applied an advanced method, Fragmented and Primer-Ligated Double-stranded (ds) RNA Sequencing (FLDS), to screen RNA viruses from 155 fungal isolates, which allowed us to obtain complete viral genomes in a homology-independent manner. We created a high-quality catalog of 19 RNA viruses (12 viral species) that infect Aspergillus isolates. Among them, nine viruses were not detectable by the conventional methodology involving agarose gel electrophoresis of dsRNA, a hallmark of RNA virus infections. Segmented genome structures were determined in 42 per cent of the viruses. Some RNA viruses had novel genome architectures; one contained a dual methyltransferase domain and another had a separated RNA-dependent RNA polymerase (RdRp) gene. A virus from a different fungal taxon (Pyricularia) had an RdRp sequence that was separated on different segments, suggesting that a divided RdRp is widely present among fungal viruses, despite the belief that all RNA viruses encode RdRp as a single gene. These findings illustrate the previously hidden diversity and evolution of RNA viruses, and prompt reconsideration of the structural plasticity of RdRp.
  • Hikaru Kanegae, Nanako Tomino, Yuichi Nakamura, Tomoko Minakawa, Takashi Yaguchi, Takeshi Izawa, Ayako Sano, Eiko Nakagawa Itano, Keiichi Ueda
    Mycopathologia 185(6) 1021-1031 2020年12月  
    The prominence of seafood in Japan motivates close monitoring of its seas and marine lives for potentially pathogenic fungi. During the treatments of the male Pacific white-sided dolphin (Lagenorhynchus obliquidens) for paracoccidioidomycosis ceti (PCM-C), 5 white and floccose colonies showing identical genotype and morphological characteristics were isolated from two skin biopsy samples of cutaneous granulomatous lesions in 2018. The isolates were identified as Parengyodontium album known as one of fungal species having abilities to produce industrially important proteases, and to become a causative agent for emerging mycosis based on morphological and molecular biological characteristics. These lesions consisted of non-malignant pearl-like structures of hyperplastic keratinocytes. Interestingly, although the isolates could grow at 35 °C, their DNA sequences were phylogenetically located in a cluster consisting of environmental and clinical isolates lacking the ability to grow at 35 °C, based on previous reports. The opportunistic infection we observed in the dolphin might be caused by immune disorder due to PCM-C. Notably, although P. album is recognized as non-harmful, and has significant industrial importance and antitumor activity, it has potential to cause not only superficial but also systemic infection, and presents difficulties in treatment because of its high resistance to antifungal compounds.
  • Asuka Takeshige, Mie Nakano, Daisuke Kondoh, Yuma Tanaka, Akio Sekiya, Takashi Yaguchi, Hidefumi Furuoka, Takahito Toyotome
    Veterinary Research 51(1) 2020年12月  
    <title>Abstract</title> Lesions of adiaspiromycosis, a respiratory disease affecting wild animals, have been found mainly in dead mammals and free-living mammals captured for surveillance. No report has described an investigation of adiaspore formation progress in the lung. After establishing an experimental mouse model of intratracheal adiaspiromycosis infection with the causative agent <italic>Emmonsia crescens</italic>, we observed adiaspore development. The spores grew and reached a plateau of growth at 70 days post-infection. The median adiaspore diameter showed a plateau of around 40 μm. The characteristic three-layer cell-wall structure of adiaspores was observed in the lung at 70 days post-infection. We examined infection with a few spores, which revealed that adiaspores in the mouse lung progressed from intratracheal infection of at least 400 spores. Moreover, we developed adiaspores in vitro by culture in fetal bovine serum. Although most spores broke, some large spores were intact. They reached about 50 μm diameter. Thick cell walls and dense granules were found as common points between in vitro adiaspores and in vivo adiaspores. These models are expected to be useful for additional investigations of <italic>E. crescens</italic> adiaspores and adiaspiromycosis.
  • Isato Yoshioka, Hiroki Takahashi, Yoko Kusuya, Takashi Yaguchi, Kohtaro Kirimura
    Microbiology resource announcements 9(33) 2020年8月13日  
    Aspergillus tubingensis WU-2223L, belonging to the section Nigri, is a hyperproducer of citric acid. Here, we present the high-quality draft (35 Mb) and mitochondrial (32.4 kb) genome sequences of this strain, which consisted of 16 scaffolds in total. The draft and mitochondrial genome sequences comprised 11,493 and 15 genes, respectively.
  • Chiharu Iwahashi, Hiroshi Eguchi, Fumika Hotta, Mayu Uezumi, Miki Sawa, Masatomo Kimura, Takashi Yaguchi, Shunji Kusaka
    BMC infectious diseases 20(1) 566-566 2020年8月3日  
    BACKGROUND: Subtenon injection of triamcinolone acetonide (STTA) has been widely adopted in the clinical setting of ophthalmology and its infectious complications are rare. However, orbital abscess following STTA has been reported in seven cases. Furthermore, although eye infections due to Exophiala species are uncommon, there have been 19 cases to date. E. jeanselmei, E. phaeomuriformis, E. werneckii, and E. dermatitidis have been reported to cause human eye infections; however, to the best of our knowledge, orbital abscess caused by E. dermatitidis has not yet been reported. We describe the first documented case of fungal orbital abscess caused by E. dermatitidis following STTA. We also review the related literature of orbital abscess following STTA, as well as eye infections caused by the four Exophiala species. CASE PRESENTATION: The patient was a 69-year-old Japanese woman with diabetic mellitus. She had a macular oedema in her right eye, which occurred secondary to branch retinal vein occlusion. An orbital abscess caused by E. dermatitidis occurred 4 months after the second STTA for the macular oedema, which was successfully treated by a surgical debridement and systemic administration of voriconazole. CONCLUSIONS: Our findings in the patient and from our literature survey caution ophthalmologists to the fact that STTA can cause fungal orbital infections, especially in diabetic patients. Furthermore, surgical treatment is one of the most important risk factors.
  • Hiromitsu Noguchi, Tadahiko Matsumoto, Utako Kimura, Masataro Hiruma, Rui Kano, Takashi Yaguchi, Satoshi Fukushima, Hironobu Ihn
    The Journal of dermatology 47(7) e251-e253 2020年7月  査読有り

MISC

 93
  • 馬目照久, 中村文香, 原康雅, 原康雅, 高屋明子, 高屋明子, 高屋明子, 伴さやか, 高橋弘喜, 高橋弘喜, 矢口貴志, 石橋正己, 石橋正己
    日本薬学会年会要旨集(Web) 143rd 2023年  
  • 三宅真未, 原康雅, 原康雅, 渡邊圭一郎, 高屋明子, 高屋明子, 高屋明子, 矢口貴志, 石橋正己, 石橋正己
    日本薬学会年会要旨集(Web) 143rd 2023年  
  • 原康雅, 渡邊圭一郎, 高屋明子, 高屋明子, 馬目照久, 矢口貴志, 石橋正己
    日本生薬学会年会講演要旨集 68th 2022年  
  • 井上 幸次, 宮崎 大, 馬場 高志, 石倉 涼子, 松浦 一貴, 長谷川 晶子, 諸星 計, 小松 恵子, 小松 直樹, 唐下 千寿, 寺坂 祐樹, 富長 岳史, 三原 幸子, 宮野 佐智子, 佐々木 慎一, 川本 由紀美, 春木 智子, 井上 美智子, 大谷 史江, 稲田 耕大, 魚谷 竜, 清水 大輔, 三宅 瞳, 江原 二三枝, 郭 權慧, 矢倉 慶子, 清水 由美子, 大橋 裕一, 下村 嘉一, 臼井 正彦, 姚 玉峰, 外園 千恵, 井上 智之, 鈴木 崇, 加藤 四郎, 上田 重晴, 前田 一洋, 佐々木 裕美, 坂本 雅子, 山田 雅夫, 林 皓三郎, 塩田 洋, 綾塚 祐二, 佐々木 香る, 浅利 誠志, 砂田 淳子, 木村 圭吾, 福田 昌彦, 江口 洋, 秦野 寛, 細貝 真弓, 山上 聡, 海老原 伸行, 鈴木 弘, 星 最智, 横倉 俊二, 望月 清文, 槇村 浩一, 矢口 貴志, 錫谷 達夫, 小杉 伊三夫, 門田 遊, 子島 良平, 八木 彰子, 古川 敏仁
    日本眼科学会雑誌 124(3) 155-184 2020年3月  
    眼感染症と他の眼疾患の大きな違いは,他の眼疾患にはホストと環境の二つが関連しているが,眼感染症はホストと微生物と環境の三者が絡み合って疾患を形成してくることにある.それだけにより複雑であり,それを読み解き,解決を図っていくためには,さまざまな手法を駆使する必要がある.本論文では,我々が基礎から臨床までさまざまな方法で眼感染症に取り組んできたこと,取り組んでいることを紹介する.1.角膜ヘルペス Herpes simplex virus(HSV)による角膜炎はウイルスの増殖とウイルスに対する免疫反応との微妙なバランスで成り立っており,いまだ根本的な解決はなされておらず,臨床的な重要性は高い.そしてそれらの解決に向けて基礎研究の積み重ねが重要で,そこには最新の研究手法が応用できる.in vitroでは,角膜上皮細胞・角膜内皮細胞にHSVを感染させてmRNAをみるマイクロアレイで網羅的に発現遺伝子を解析し,その結果,重要性が判明した遺伝子の中で,interferon regulatory factor 7(IRF7)やindoleamine 2,3-dioxygenase 1(IDO1)のHSVに対する免疫反応への関与を解析してきた.in vivoではヘルペス制御に対するワクチンの試みやケモカイン受容体と角膜実質炎の関係,新しい抗ヘルペス薬アメナメビルの効果の可能性をマウスのHSV角膜炎モデルで検討してきた.臨床への研究手法の応用としてreal-time polymerase chain reaction(PCR)による診断を行ってきた.2.サイトメガロウイルス角膜内皮炎 2006年の小泉らの報告以来多くの研究・報告がなされているが,その病態はいまだ不明である.我々も臨床例における前房内のサイトメガロウイルス(CMV)-DNA量が種々の臨床的パラメーターと相関していること,CMVが角膜内皮細胞や線維柱帯細胞に実際に感染し,サイトカイン産生を含め,さまざまな反応を惹き起こしてくること,CMV感染角膜内皮細胞によるCD8陽性細胞傷害性T細胞誘導がCMV角膜内皮炎患者では低下していることなどを見出してきた.3.真菌性角膜炎多施設スタディ 日本眼感染症学会においてプロスペクティブな多施設観察研究として,起因真菌とその薬剤感受性・臨床所見や予後に関与する因子を検討した.多種多様な真菌が原因となっていることが,遺伝子解析で明らかとなり,in vitroの感受性検査では,ピマリシンとアゾール系の組み合わせで拮抗を示す株もあることが判明した.4.角膜感染症への人工知能応用の試み 現在多くの眼疾患への人工知能(AI)の応用が試みられており,今後日本眼科学会主導でAI研究が行われていくが,我々もImageNetデータベースの一般画像を用いて事前学習させた畳み込みニューラルネットワークというアルゴリズムに感染性角膜炎の細隙灯顕微鏡写真を学習させ,比較的良好な診断確度を得つつある.また,それと並行して細隙灯顕微鏡写真以外のデータ(培養・real-time PCR)を用いた診断モデルの構築もランダムフォレストなど別のアルゴリズムを用いて行っている.将来的にはこれを統合させることでAIによる診断が可能になると思われる.5.術後眼内炎予防 白内障術後眼内炎の予防についてはさまざまな試みが行われている.日本眼感染症学会主導の多施設スタディにおいて手術3日前からの抗菌点眼薬使用によって結膜嚢常在菌を減らすことができることを証明したが,その後ヨード製剤の術中使用や抗菌薬の前房内投与が行われるようになってきたこと,耐性菌対策が重要となってきたことなどから,術前抗菌点眼薬使用を見直す必要が出てきていると思われる.我々は術中ヨード製剤の使用によって,結膜嚢常在菌が減ること,また,術中ヨード製剤の使用が術前抗菌点眼薬使用に劣らない減菌効果を示すことをプロスペクティブスタディで証明した.これまで,眼感染症に関するさまざまな問題に対して研究が行われ,我々もそれに継続的に参画してきたが,今後も眼感染症は眼科臨床において重要な問題を提起し続けると思われ,最新の医学を貪欲に取り入れつつ,基礎から臨床にわたる幅広いアプローチでこの古くて新しい脅威に立ち向かっていく必要がある.(著者抄録)
  • 北原 博一, 稲本 伸子, 本田 治樹, 矢口 貴志, 佐藤 友隆
    臨床皮膚科 73(6) 435-439 2019年5月  
    <文献概要>77歳,男性.眉毛部の紅斑を主訴に受診.ステロイド外用にて治療開始したが,紅斑が増悪した.眉毛のKOH直接鏡検より菌糸を認め,顔面白癬と診断した.妻にMicrosporum canisによる顔面白癬で,テルビナフィン内服による加療歴があり,また敷地内に野良猫が複数おり容易に接触できる環境であったためM. canisによる顔面白癬を疑った.一方で患者の足趾爪甲に白濁病変があり,鏡検にて菌糸を認め爪白癬と診断した.顔面白癬の原因菌を同定するため,眉毛および爪から培養したところ,同様の集落を形成し,菌学的検査にて両者ともTrichophyton rubrumと確定した.顔面白癬の感染経路として,動物や柔道・レスリング選手同士などでの感染が報告される一方で,爪白癬などによる自家播種も考慮すべきであり,感染源特定に培養同定検査が有用であった1例を報告する.

共同研究・競争的資金等の研究課題

 10