掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/microorganisms14040760

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Staphylococcus aureus potentially causes systemic infections such as disseminated abscesses and bloodstream infections, leading to high mortality rates. We herein describe a case of disseminated muscle abscesses caused by sequence type (ST) 398 methicillin-sensitive S. aureus (MSSA), along with in vitro investigation results for potential pathogenic factors. A 67-year-old healthy woman was admitted to our hospital with complaints of systemic body pain. Blood cultures identified MSSA and contrast-enhanced computed tomography revealed multiple muscle abscesses extending from her neck to her soles. She received antibiotic treatment with intravenous cephazolin and underwent repeated surgical drainage, and was finally discharged. Notably, the MSSA strain exclusively affected her muscle tissues, prompting us to perform genetic analysis to uncover the underlying reason. Short-read genome analysis revealed the isolate to be ST398, harboring chp and scn genes known for immune evasion from human immunity. However, no other known pathogenic factors were identified despite rigorous assays for biofilm formation, surface and cell wall proteins, protease production, and hyaluronidase activity. ST398 S. aureus is commonly isolated from livestock, and her prior experience of being flooded could be related to the disease onset. The present case underscores the possibility of severe ST398 MSSA infections in humans, even in the absence of direct animal exposure.

DOI： 10.1016/j.jiac.2025.102845

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担当区分：筆頭著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Oxford University Press (OUP)  

Abstract

Aims

Edible insects, including crickets, represent a promising protein source, yet concerns over foodborne pathogens limit consumer acceptance. This study investigated whether gut microbiota modulates colonization by Salmonella enterica subsp. enterica serovar Enteritidis (SE) in the two-spotted cricket (Gryllus bimaculatus).

Methods and Results

Under standard conditions, SE was undetectable in crickets despite prolonged exposure; however, antibiotic-induced dysbiosis enabled stable SE colonization. Long-read 16S rRNA sequencing revealed significant microbiota shifts, notably a reduction in Lactococcus garvieae. In vitro assays showed strong inhibitory effects of L. garvieae against SE, and supplementation of dysbiotic crickets with L. garvieae reduced SE colonization by ∼1,000-fold.

Conclusions

The native cricket gut microbiota, especially L. garvieae, plays a protective role against SE colonization. Enhancing beneficial gut bacteria could mitigate pathogen risks and promote edible insects as a sustainable protein.

DOI： 10.1093/jambio/lxaf217

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Sarcopenia, characterized by skeletal muscle atrophy, was previously considered age-related; however, it is also associated with other diseases. Nonalcoholic fatty liver disease (NAFLD) is known to cause sarcopenia, and its complications have been reported to affect prognosis. The intestinal microbiota of patients with NAFLD or sarcopenia has been found to be altered compared to that of healthy individuals. However, the alterations that occur when both diseases coexist in humans or experimental animals remain unclear. Therefore, this study aimed to determine the intestinal microbiota changes associated with NAFLD with sarcopenia in SHRSP5/Dmcr rats at the time of concomitant disease. Fecal samples were collected from the rectum of SHRSP5/Dmcr rats fed a normal diet (non-NAFLD and non-Sarcopenia, n = 5) or a high-fat and high-cholesterol diet (NAFLD and Sarcopenia, n = 5) for 20 weeks, and subjected to 16S rRNA analysis. In the NAFLD and sarcopenia group, the diversity of the intestinal microbiota was reduced; further, the bacterial species reported in patients with NAFLD or sarcopenia were also changed. At the family level, the abundances of Akkermansiaceae, Bacteroidaceae, and Tannerellaceae were significantly higher whereas Ruminococcaceae and Lactobacillaceae were decreased in the NAFLD and sarcopenia group. At the genus level, the abundances of Akkermansia, Bacteroides, Ruminococcus, and Parabacteroides were significantly higher whereas the abundance of Lactobacillus was significantly decreased in the NAFLD and sarcopenia group. Overall, these findings help improve the existing understanding regarding the intestinal microbiota changes observed in conditions where NASH and sarcopenia co-occur.

DOI： 10.1007/s12223-025-01283-3

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記述言語：日本語   出版者・発行元：日本感染症学会・日本化学療法学会  

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/j.ijregi.2024.100511

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Society of Hematology  

The oral microbiota, second in abundance to the gut, is implicated in chronic systemic diseases, but its specific role in GVHD pathogenesis has been unclear. Our study finds that mucositis-induced oral dysbiosis in patients post-hematopoietic cell transplantation associated with increased chronic GVHD (cGVHD) even in patients receiving post-transplant cyclophosphamide. In murine HCT models, oral dysbiosis caused by bilateral molar ligatures exacerbated cGVHD and increased bacterial load in the oral cavity and gut with Enterococcaceae significantly increasing in both organs. In this model, the migration of Enterococcaceae to cervical lymph nodes (LNs) both pre- and post-transplantation activated antigen-presenting cells (APCs), thereby promoting the expansion of donor-derived inflammatory T cells. Based on these results, we hypothesize that pathogenic bacteria increased in the oral cavity might not only exacerbate local inflammation but also enhance systemic inflammation throughout the HCT course. Additionally, these bacteria translocated to the gut and formed ectopic colonies, further amplifying systemic inflammation. Furthermore, interventions targeting the oral microbiome mitigated murine cGVHD. Collectively, our findings highlight the importance of oral dysbiosis in cGVHD and suggest that modulation of the oral microbiome during transplantation may be an effective approach for preventing or treating cGVHD.

DOI： 10.1182/blood.2024024540

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

INTRODUCTION: Corynebacterium species potentially develop high-level daptomycin resistance (HLDR) shortly after daptomycin (DAP) administration. We aimed to investigate the clinical and microbiological characteristics of HLDR Corynebacterium infections. METHODS: We first presented a clinical case accompanied by the results of a comprehensive genetic analysis of the isolate, and then performed a systematic scoping review. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews, we searched for articles with related keywords, including "Corynebacterium", "Daptomycin", and "Resistance", in the MEDLINE and Web of Science databases from the database inception to October 25, 2024. Clinical case reports and research articles documenting the isolation of HLDR Corynebacterium species, defined by a minimum inhibitory concentration of DAP at ≥256 μg/mL, were deemed eligible for this review. RESULTS: Of 80 articles screened, seven case reports detailing eight cases of HLDR Corynebacterium infections, as well as five research articles, were included. C. striatum was the most common species (7/9 cases, 77.8%), and prosthetic device-associated infections accounted for 66.7% of the cases. Duration of DAP administration before the emergence of HLDR isolates ranged from 5 days to 3 months; three-quarters of the cases developed within 17 days. Three HLDR isolates were genetically confirmed to have an alteration in pgsA2. The majority of the patients were treated with either glycopeptides or linezolid, with favorable outcomes. In vitro experiments confirmed that C. striatum strains acquire the HLDR phenotype at higher rates (71% to 100%) within 24 hours of incubation, compared to other Corynebacterium strains CONCLUSION: DAP monotherapy, especially for prosthetic device-associated infections, can result in the development of HLDR Corynebacterium. Additional research is warranted to investigate the clinical implications of this potentially proliferating antimicrobial resistant pathogen.

DOI： 10.1016/j.jiac.2024.12.004

PubMed

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Spread of carbapenemase-producing Enterobacterales (CPE) is an ongoing public health issue worldwide, including in Japan. In this study, we investigated the phenotypic and genetic characteristics of CPE isolates at Okayama University Hospital over the 5 years (2013-2018) prior to the outbreak of the 2019 coronavirus pandemic. Of 24 carbapenem-resistant Enterobacterales isolated during the study period, we identified 8 CPE isolates harboring blaIMP-1 (5 isolates) and blaIMP-6 genes (3 isolates). Bacterial species and carbapenem susceptibility patterns exhibited diversity. Minimum inhibitory concentrations (MICs) of meropenem were generally higher than those of imipenem and biapenem. Results of pulsed-field gel electrophoresis demonstrated that neither clonal nor plasmid-mediated outbreaks of blaIMP-harboring CPE isolates have developed at our hospital. One Klebsiella oxytoca isolate showed a high MIC (128 μg/mL) of meropenem, which could be explained by the high plasmid copy number. Subsequent analysis of this isolate may elucidate the intricacies of carbapenem resistance profiles among CPE isolates. Collectively, our findings underscore the necessity for ongoing genetic surveillance of CPE, complemented by tailored approaches for infection prevention and control.

DOI： 10.18926/AMO/67657

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担当区分：筆頭著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/j.diagmicrobio.2024.116399

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Oxford University Press (OUP)  

We have isolated a blaNDM-1-harbouring ST147 Klebsiella pneumoniae strain from a Ukrainian immigrant hospitalized at a Japanese hospital, which was genetically corroborated to be highly identical to a Russian-derived isolate. This case highlights that the geopolitical risk potentially increases the global dissemination of antimicrobial resistance pathogens.

DOI： 10.1093/jtm/taae011

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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記述言語：日本語   出版者・発行元：(一社)日本臨床微生物学会  

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