Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

ABSTRACT

This study assessed the role of high mobility group box 1 (HMGB1) in pneumococcal pneumonia. Intratracheal challenge of mice with Streptococcus pneumoniae significantly increased HMGB1 levels in bronchoalveolar lavage fluid. Immunostaining of lung sections revealed HMGB1 localization in both alveolar epithelial and infiltrating polymorphonuclear cells in S. pneumoniae ‐infected mice. In vitro, pneumolysin, a pore‐forming pneumococcal toxin, causes HMGB1 release from neutrophils. Additionally, recombinant HMGB1 enhanced TNF‐α production in RAW264.7 macrophages, human neutrophils, and THP‐1 cells. These findings indicate that neutrophil‐derived HMGB1 serves as a pro‐inflammatory mediator and exacerbates of lung inflammation during pneumococcal infection.

DOI： 10.1111/1348-0421.70054

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/1348-0421.70054

Publishing type：Research paper (scientific journal)   Publisher：Bioscientifica  

Objective

Interactions between the dental biofilm and host are important to study infectious oral diseases such as dental caries and periodontitis. Previous studies have reported the reaction of a host gingival model cocultured with bacteria or biofilms. However, these studies only report results of a gingival model, and a biofilm cocultured with a gingival model has never been investigated, although the microbiome of dental biofilms is associated with the maintenance of health and the onset of infectious oral diseases. Therefore, we aimed to investigate the reaction of a gingival model and experimental biofilm. An in situ dental biofilm model, which enables biofilm formation in the oral cavity, was used to prepare experimental biofilms.

Methods

The in situ biofilm was cocultured with a reconstructed human gingival (RHG) model. We performed 16S rRNA sequence analysis, metagenomic function prediction analysis, total bacterial cell counts using quantitative polymerase chain reaction and confocal laser microscopy observation in addition to gene expression and histological investigation of RHG.

Results

We found a change in Veillonella abundance in the in situ biofilms cocultured with RHG. Metagenomic function prediction analysis revealed that the activity of certain pathways associated with amino acid production, lactic acid fermentation and the glycolysis system significantly increased in biofilms cocultured with RHG.

Conclusion

The microbiome and functions of dental biofilms can be affected by host gingival tissues. Our findings will contribute to the establishment of a host–biofilm interaction model to understand the pathophysiology of oral infectious diseases.

DOI： 10.1530/mah-24-0008

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Other Link： https://mah.bioscientifica.com/downloadpdf/journals/mah/3/1/MAH-24-0008.xml

Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

This study aimed to assess the antibiofilm effects of dentin desensitizers using a modified Robbins device flow cell system. The test desensitizers were Saforide, Caredyne Shield, and Clinpro White Varnish. Standardized dentin specimens were prepared from human single-rooted premolars, treated with one of the materials, and mounted on the modified Robbins device flow cell system. Streptococcus mutans biofilms were developed for 24 h at 37 °C under anaerobic conditions. Scanning electron microscopy, fluorescence confocal laser scanning microscopy, viable and total cell counts, acid production, and gene expression analyses were performed. A wavelength-dispersive X-ray spectroscopy electron probe microanalyzer was used to analyze the ion incorporations. Clinpro White Varnish showed the greatest inhibition, suggesting its suppression of bacterial adherence and transcription of genes related to biofilm formation. Saforide reduced only the number of viable bacteria, but other results showed no significant difference. The antibiofilm effects of Caredyne Shield were limited. The uptake of ions released from a material into dentin varies depending on the element. Clinpro White Varnish is effective for the short-term treatment of tooth sensitivity due to dentin demineralization. It prioritizes remineralization by supplying calcium and fluoride ions while resisting biofilm formation.

DOI： 10.3390/ijms251910703

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/antibiotics13080743

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jbc.2024.107384

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Language：Japanese  

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Language：Japanese  

J-GLOBAL

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Event date： 2025.9

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Event date： 2024.11

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2024.8

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Author：Other 

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