Cariogenicity of Candida albicans of distinct genotypes among 3-5-year-old Uygur children in Kashgar, China- a case-control study

Investigating the association between Candida albicans and early childhood dental caries: A comprehensive systematic review and meta-analysis

BACKGROUND

Early childhood caries (ECC) is a significant public health concern affecting children globally. Recent studies suggest a potential association between the presence of Candida albicans (C. albicans) in the oral cavity and the risk of ECC, but findings have been inconsistent. This systematic review and meta-analysis aimed to investigate the association between C. albicans and ECC.

METHODS

A comprehensive literature search was conducted across databases including PubMed, Web of Science, Cochrane Central Register of Controlled Trials, Embase, Google Scholar, and Scopus. Studies were included if they examined the presence of C. albicans and the occurrence or severity of dental caries in children. Data extraction and quality assessment were performed independently by two reviewers. Statistical analyses, including pooled odds ratios (OR) and 95% confidence intervals (CI), were conducted to synthesize the findings.

RESULTS

A total of 22 studies, involving 3301 participants, were included in the meta-analysis. The findings revealed a significant association between the presence of C. albicans and an increased likelihood of ECC, with a pooled odds ratio (OR) of 4.42 (95% CI: 3.14-6.24, p < 0.001). Subgroup analyses showed that factors such as geographic region, study design, and detection methods influenced the strength of this association. Studies conducted in Europe reported a stronger association (OR: 10.13, 95% CI: 6.01-17.09) compared to those in Asia (OR: 3.62, 95% CI: 2.53-5.20) and the Americas (OR: 3.98, 95% CI: 1.14-13.87). Case-control studies had a higher pooled OR (5.30, 95% CI: 1.72-16.31) compared to cross-sectional studies (4.30, 95% CI: 2.92-6.33). The odds of ECC in children with C. albicans were 4.08 (95% CI: 2.65-6.27) in dental plaque samples, 9.55 (95% CI: 2.17-42.01) in oral swab samples, and 4.70 (95% CI: 2.44-9.09) in saliva samples. No publication bias was observed based on Begg's test (P-value = 0.612) and Egger's test (P-value = 0.250).

CONCLUSIONS

The findings provide support for the hypothesis that C. albicans plays a role in the development of ECC. Moving forward, it is essential for future research to concentrate on comprehending the mechanisms that underlie this relationship and to develop specific strategies for prevention.

Whole-Exome Sequencing Implicates the USP34 rs777591A > G Intron Variant in Chronic Obstructive Pulmonary Disease in a Kashi Cohort

Genetic factors are important factors in chronic obstructive pulmonary disease (COPD) onset. Plenty of risk and new causative genes for COPD have been identified in patients of the Chinese Han population. In contrast, we know considerably little concerning the genetics in the Kashi COPD population (Uyghur). This study aims at clarifying the genetic maps regarding COPD susceptibility in Kashi (China). Whole-exome sequencing (WES) was used to analyze three Uyghur families with COPD in Kashi (eight patients and one healthy control). Sanger sequencing was also used to verify the WES results in 541 unrelated Uyghur COPD patients and 534 Uyghur healthy controls. WES showed 72 single nucleotide variants (SNVs), two deletions, and small insertions (InDels), 26 copy number variants (CNVs), and 34 structural variants (SVs), including g.71230620T > A (rs12449210T > A, NC_000,016.10) in the HYDIN axonemal central pair apparatus protein (HYDIN) gene and g.61190482A > G (rs777591A > G, NC_000002.12) in the ubiquitin-specific protease 34 (USP34) gene. After Sanger sequencing, we found that rs777591“AA” under different genetic models except for the dominant model (adjusted OR = 0.8559, 95%CI 0.6568–1.115, p > .05), could significantly reduce COPD risk, but rs12449210T > A was not related to COPD. In stratified analysis of smoking status, rs777591“AA” reduced COPD risk significantly among the nonsmoker group. Protein and mRNA expression of USP34 in cigarette smoke extract-treated BEAS-2b cells increased significantly compared with those in the control group. Our findings associate the USP34 rs777591“AA” genotype as a protector factor in COPD.

Profuse diversity and acidogenicity of the candida-biome of deep carious lesions of Severe Early Childhood Caries (S-ECC)

Introduction: The retentive niches of deep caries lesions have a distinct biome. Methods: We evaluated the site-specific (occlusal and proximal) Candida-biome of Severe-Early Childhood Caries (S-ECC) in 66- children (132 lesions). Asymptomatic primary molars fitting the definition of the International Caries Detection and Assessment-(ICDAS)-caries-code 5/6 were analyzed. Deep-dentinal sampling and simultaneous assessment of pH were performed. Clinical isolates were speciated using multiplex-PCR and evaluated for their acidogenic and aciduric potential.Results: Surprisingly, a high prevalence of Candida species (72.7%), either singly or in combination, was noted from both the proximal and occlusal cavities. C. tropicalis was the most prevalent species (47%; 34/72), followed by C. krusei (43.1%; 31/72) and C. albicans (40.3%; 29/72), with C. glabrata being the least (9.7%; 7/72). Over 45% low-pH niches (pH <7) of both sites yielded either dual or triple species of Candida. Genotyping revealed three distinct C. albicans genotypes (A, B, and C) with (14/29; 48.3%) of strains belonging to Genotype A. All four evaluated Candida species exhibited acidogenic and aciduric potential, C. tropicalis being the most potent.Conclusion: This, the first report of the high-density, multispecies, yeast colonization of deep-dentinal lesions in S-ECC, suggests that the Candida-biome plays a significant etiologic role in the condition, possibly due to their profound acidogenicity in milieus rich in dietary carbohydrates.

Oral candidal carriage and its association with dental carious lesions in asymptomatic adults: a cross-sectional study from the UAE

BACKGROUND

Candida's potential association with dental caries has previously been reported in children. This research aimed at investigating the associations between Candida species in whole saliva and dental and periodontal health indices in a sample of adult patients.

METHODS

A cross-sectional study involving 160 patients investigated the associations between Candida species collected by oral rinse technique, and Decayed, Missing, and Filled Surfaces (DMFS), and periodontal health indices. Chi-square and Independent Samples t-test were used to assess the associations between Candida carriage and confounding variables. Binary logistic regression was used to assess association strengths between Candida carriage and DMFS, adjusted for socio-demographic variables, diabetes mellitus and plaque index.

RESULTS

Candida colonies were identified in 49 (30.6%) patients with CFUs ranging from 10³ to 10⁵ colonies per mL. The quantity of Candida CFUs increased with age (r = 0.200; p < 0.05). Among all dental and periodontal health indices, only DMFS was significantly associated with higher values of Candida carriage (p = 0.034), and this association was independent from sex, age, smoking, diabetes mellitus and plaque index (OR: 1.014; 95% CI 1.0-1.03; p = 0.048).

CONCLUSION

The association between Candida species in whole saliva and DMFS reported here supports an etiological role of Candida in dental cariogenesis among adults.

Site-Specific Profiling of the Dental Mycobiome Reveals Strong Taxonomic Shifts during Progression of Early-Childhood Caries

Dental caries is one of the most common diseases worldwide. Bacteria and fungi are both commensals in the oral cavity; however, most research regarding caries has focused on bacterial impacts. The oral fungal mycobiome associated with caries is not well characterized, and its role in disease is unclear. ITS1 amplicon sequencing was used to generate taxonomic profiles from site-specific supragingival plaque samples (n = 82) obtained from 33 children with different caries status. Children were either caries free (CF), caries active with enamel lesions (CAE), or caries active with dentin lesions (CA). Plaque samples were collected from caries-free surfaces (PF) and from enamel (PE) and dentin (PD) lesions. Taxonomic profiles representing the different categorizations (CF-PF, CAE-PF, CAE-PE, CA-PF, CA-PE, and CA-PD) were used to characterize the mycobiome and its change through disease progression. A total of 139 fungal species were identified. Candida albicans was the most abundant species, followed by Candida dubliniensis We found that severely progressed plaque communities (CA-PD) were significantly different from healthy plaque communities (CF-PF). A total of 32 taxa were differentially abundant across the plaque categories. C. albicans, C. dubliniensis, Nigrospora oryzae, and an unclassified Microdochium sp. were correlated with caries, whereas 12 other taxa were correlated with health. C. dubliniensis increased steadily as caries progressed, suggesting that C. dubliniensis may play an important role in caries pathogenicity. In contrast, four health-associated fungal taxa have the potential to antagonize the cariogen Streptococcus mutans via xylitol production, suggesting a possible fungal mechanism that could contribute to maintenance of dental health.IMPORTANCE Early-childhood caries is one of the most prevalent diseases in children worldwide and, while preventable, remains a global public health concern. Untreated cavities are painful and expensive and can lead to tooth loss and a lower quality of life. Caries are driven by acid production via microbial fermentation of dietary carbohydrates, resulting in enamel erosion. While caries is a well-studied disease, most research has focused on bacterial impacts, even though fungi are commensal organisms living within the plaque biofilm. There is very little known about how fungi impact caries pathogenicity. The elucidation of fungal taxa involved in caries disease progression is necessary for a more holistic view of the human oral microbiome. Data from this study will improve our understanding of how the fungal community changes as disease progresses and provide insight into the complex etiology of dental caries, which is necessary for the development of treatment plans and preventative measures.