We aimed to explore saliva microbiome alterations in dental fluorosis population.The prevalence of dental fluorosis was examined in 957 college students. Dean’s fluorosis index was used to evaluate...

Streptococcus mutans is a major pathogen responsible for dental caries. Arginine is a promising potential caries preventive agent which can inhibit the growth of S. mutans. However, the mechanism w...

Streptococcus mutans (S. mutans) is one of the primary pathogens responsible for dental caries. Streptococcus gordonii (S. gordonii) is one of the early colonizers of dental plaque and can compete with S. mutans for growth. In the present analysis, we explored key target genes against S. gordonii in S. mutans using 80 S. mutans clinical isolates with varying capabilities against S. gordonii. A principal coordinate analysis revealed significant genetic diversity differences between antagonistic and non-antagonistic groups. Genomic comparisons revealed 33 and 61 genes that were, respectively, positively and negatively correlated with S. mutans against S. gordonii, with RNA-sequencing (RNA-seq) highlighting 11 and 43 genes that were, respectively, upregulated and downregulated in the antagonistic group. Through a combination of these results and antiSMASH analysis, we selected 16 genes for qRT-PCR validation in which the expression levels of SMU_137 (malate dehydrogenase, mleS), SMU_138 (malate permease, mleP), SMU_139 (oxalate decarboxylase, oxdC), and SMU_140 (glutathione reductase) were consistent with RNA-seq results. SMU_1315c-1317c (SMU_1315c transport-related gene) and SMU_1908c-1909c were, respectively, downregulated and upregulated in the antagonistic group. The expression patterns of adjacent genes were closely related, with correlation coefficient values greater than 0.9. These data reveal new targets (SMU_137–140, SMU_1315c-1317c, and SMU_1908c-1909c) for investigating the critical gene clusters against S. gordonii in S. mutans clinical isolates.

Streptococcus mutans is regarded as a major pathogen responsible for the onset of dental caries. S. mutans can transmit among people, especially within families. In this study, we established a new epidemiological approach to S. mutans classification. This approach can effectively differentiate among closely related isolates and offers superior reliability relative to that of the traditional MLST molecular typing method. As such, it has the potential to better support effective public health strategies centered around this bacterium that are aimed at preventing and treating dental caries.

Aim: To investigate the systemic immune-inflammation index and prognostic immune nutritional index in the prognostic evaluation of oral squamous cell carcinoma.Materials & methods: We analyzed retrospectively the relationship between systemic immune-inflammation index, prognostic immune nutritional index and clinicopathological variables and the overall survival of 262 patients who underwent radical surgery.Results: Multivariate analysis showed high systemic immune-inflammation index (Hazard ratio = 3.062, 95% CI: 1.021-8.251), low prognostic immune nutritional index (Hazard ratio = 0.297, 95% CI: 0.139-0.636), tumor node metastasis classification 3-4 (Hazard ratio = 9.862, 95% CI: 4.658-20.880) patients have worse overall survival.Conclusion: Preoperative systemic immune-inflammation index and prognostic immune nutritional index are independent risk factors for prognostic survival status in oral squamous cell carcinoma.