Background: Given the escalating resistance of Candida albicans biofilms to conventional antifungal agents, in this research, we evaluated the potential of combination therapy comprising hinokitiol (HNK) and fluconazole (FLZ), as an alternative, for combating biofilm-associated infections. Methods: To assess their synergistic effects, the fractional inhibitory concentration index was calculated. The viability of biofilms and intracellular oxidative stress were quantified by XTT and reactive oxygen species assays. Structural integrity and viability were further investigated by fluorescence and scanning electron microscopy; gene expression levels were measured by real-time fluorescence analysis. Results: Treatment with HNK combined with FLZ led to noticeable disruptions in the biofilm architecture of Candida albicans and resulted in significant modulation of multiple biofilm-associated genes, such as ALS3 and HWP1. The observed increase in oxidative stress, together with a marked decline in biofilm viability, provided strong support for a synergistic effect between the two compounds. Conclusions: The findings in this study revealed a potential synergistic effect between HNK and FLZ, with influences on fungal biofilm architecture and modulation of genetic pathways associated with biofilm development.

Background: Given the escalating resistance of Candida albicans biofilms to conventional antifungal agents, in this research, we evaluated the potential of combination therapy comprising hinokitiol (HNK) and fluconazole (FLZ), as an alternative, for combating biofilm-associated infections. Methods: To assess their synergistic effects, the fractional inhibitory concentration index was calculated. The viability of biofilms and intracellular oxidative stress were quantified by XTT and reactive oxygen species assays. Structural integrity and viability were further investigated by fluorescence and scanning electron microscopy; gene expression levels were measured by real-time fluorescence analysis. Results: Treatment with HNK combined with FLZ led to noticeable disruptions in the biofilm architecture of Candida albicans and resulted in significant modulation of multiple biofilm-associated genes, such as ALS3 and HWP1. The observed increase in oxidative stress, together with a marked decline in biofilm viability, provided strong support for a synergistic effect between the two compounds. Conclusions: The findings in this study revealed a potential synergistic effect between HNK and FLZ, with influences on fungal biofilm architecture and modulation of genetic pathways associated with biofilm development.

This study aimed to determine whether intranasal hinokitiol modulates short-term sal-ivary secretory IgA (SIgA) secretion dynamics and IgA antibody-forming cell (AFC) ac-tivity in the submandibular glands of aged mice, a model of age-associated mucosal immune decline. Aged BALB/c mice received intranasal hinokitiol (50 μg) once weekly for 4 weeks. Saliva was collected on days 0, 7, 14, and 21 at baseline, 0.5 h, 1.5 h, 3 h, and 6 h after each administration. SIgA levels were measured using an enzyme-linked im-munosorbent assay. On Day 21, IgA AFCs were enumerated using an enzyme-linked immunosorbent spot assay, and their viability and proliferative activity were assessed using the MTT assay. Salivary SIgA rose transiently after each dose, peaking at 1.5 h and returning to baseline by 6 h. By Day 21, baseline SIgA secretion was significantly higher than at Day 0, indicating a cumulative effect. IgA AFCs were unchanged in number, but viability and proliferation increased at 0.5 and 1.5 h, coinciding with SIgA peaks. Flow cytometry revealed significant expansion of B220⁺CD38⁺ memory B-cells; B220⁺CD138⁺ plasma cells were unaffected. Intranasal hinokitiol transiently enhances salivary SIgA secretion in aged mice, likely through short-term modulation of salivary gland immune activity. This non-invasive approach may aid mucosal defense in aging populations.

Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic epithelial tumor that primarily affects the mandible. Due to its nonspecific clinical and radiographic features, preoperative diagnosis is often difficult. We report an asymptomatic case of CCOC in an elderly woman in her eighties, in whom a mandibular radiolucent lesion was incidentally detected during routine dental examination. Imaging revealed a well-defined radiolucent lesion with lingual cortical bone perforation. Incisional biopsy suggested CCOC or a salivary gland tumor. Marginal mandibulectomy was performed, and histopathological examination demonstrated infiltrative nests of clear and polygonal epithelial cells containing abundant diastase-sensitive PAS-positive intracytoplasmic glycogen granules. Immunohistochemical staining was positive for cytokeratin (AE1/AE3) and p63, supporting the diagnosis of CCOC. No recurrence or metastasis has occurred during 8 years of follow-up. CCOC should be included in the differential diagnosis of asymptomatic mandibular radiolucent lesions, and long-term follow-up is required.

Background/Objectives: Oral functional decline is associated not only with impaired oral conditions, such as poor oral hygiene, oral dryness, decreased occlusal force, reduced masticatory performance, low tongue pressure, impaired tongue–lip motor function, and dysphagia, but also with deterioration in overall systemic health. Saliva plays a crucial role in maintaining oral function. This study investigated the relationships between conditions related to oral functional decline and salivary biomarkers. Methods: Elderly people residing in the Kyotango area were evaluated using oral function assessments, including the oral hygiene status, salivary flow rate, occlusal force, masticatory performance, tongue pressure, tongue–lip motor function, and swallowing function. Salivary biomarkers were evaluated using an oral environment assessment system (SillHa, Arkray, Kyoto). The biomarkers tested included cariogenic bacteria, acidity, buffering capacity, leukocytes, protein, and ammonia. Statistical analyses were performed using SPSS version 30 (IBM, Armonk, NY, USA). Results: Significant differences and correlations were observed between salivary biomarkers and five of the seven assessment criteria for oral functional decline: a poor oral hygiene status, oral dryness, decreased occlusal force, impaired tongue–lip motor function, and decreased masticatory function. A poor oral hygiene status was associated with the bacterial count and cariogenic bacteria. Oral dryness was associated with the salivary flow rate, acidity, and buffering capacity. Decreased occlusal force was associated with the number of remaining teeth, cariogenic bacteria, acidity, leukocytes, and protein. Impaired tongue–lip motor function was associated with the /pa/, /ta/, and /ka/ sounds and leukocytes. Decreased masticatory function was associated with masticatory performance, cariogenic bacteria, leukocytes, and protein. Conclusions: The present results suggest the potential of salivary biomarker testing using this assessment system as a simple and practical screening tool for identifying oral functional decline. Furthermore, salivary biomarker testing may be useful in oral function assessments.