Multistability and hysteresis in states of oral microbiota: Is it impacting the dental clinical cohort studies?

INTRODUCTION: Microbiome from a "healthy cohort" is used as a reference for comparison to cases and intervention. However, the studies with cohort-based clinical research have not sufficiently accounted for the multistability in oral microbial community. The screening is limited to phenotypic features with marked variations in microbial genomic markers. Herein, we aimed to assess the stability of the oral microbiome across time from an intervention-free "healthy" cohort. METHODS: We obtained 33 supragingival samples of 11 healthy participants from the biobank. For each participant, we processed one sample as baseline (T0) and two samples spaced at 1-month (T1) and 3-month (T2) intervals for 16S ribosomal RNA gene sequencing analysis. RESULTS: We observed that taxonomic profiling had a similar pattern of dominant genera, namely, Rothia, Prevotella, and Hemophilus, at all time points. Shannon diversity revealed a significant increase from T0 (p < .05). Bray Curtis dissimilarity was significant (R = -.02, p < .01) within the cohort at each time point. Community stability had negative correlation to synchrony (r = -.739; p = .009) and variance (r = -.605; p = .048) of the species. Clustering revealed marked differences in the grouping patterns between the three time points. For all time points, the clusters presented a substantially dissimilar set of differentially abundant taxonomic and functional biomarkers. CONCLUSION: Our observations indicate towards the presence of multistable states within the oral microbiome in an intervention-free healthy cohort. For a conclusive and meaningful long-term reference, dental clinical research should account for multistability in the personalized therapy approach to improve the identification and classification of reliable markers.

Introducing the FATLIPS acronym for assessing the red flag clinical features of dental infection.

Introduction Dental infection can progress to life-threatening cervicofacial and deep space infections. Therefore, safe management requires early identification of serious infections in primary care with appropriate referral to secondary care. We have developed an acronym to aid assessment of the red flag clinical features for serious dental infection in primary care by general dental practitioners.Materials and methods Literature review and focus group discussions.Results We introduce the FATLIPS acronym for assessment of red flag features of dental infection: failed previous treatment(s), airway compromise, trismus, look (lower border mandible, orbit, oral, neck), immunosuppression, pyrexia, swallowing difficulties.Conclusion We propose the FATLIPS red flags acronym to help dentists assess the red flag features of dental infections in primary care.

Could we have prevented all this? A comparison of the British and South Korean primary dental care response to COVID-19.

To limit the spread of the novel coronavirus (COVID-19), Britain enforced a strict national lockdown, which is affecting the lives of millions, including dental professionals. As a result, all routine dental work has been suspended and general dental practitioners (GDPs) are inevitably faced with financial difficulties, as well as an impending strain on dental services once the lockdown is lifted. In contrast, South Korea (SK) has effectively managed to keep the virus at bay without a lockdown and continues to deliver routine dental care throughout this period. This article compares the current status of primary dental care in the UK and SK under COVID-19, in order to explore how the dental profession can better mitigate the repercussions of a future epidemic crisis.

Nesprin interchain associations control nuclear size.

Nesprins-1/-2/-3/-4 are nuclear envelope proteins, which connect nuclei to the cytoskeleton. The largest nesprin-1/-2 isoforms (termed giant) tether F-actin through their N-terminal actin binding domain (ABD). Nesprin-3, however, lacks an ABD and associates instead to plectin, which binds intermediate filaments. Nesprins are integrated into the outer nuclear membrane via their C-terminal KASH-domain. Here, we show that nesprin-1/-2 ABDs physically and functionally interact with nesprin-3. Thus, both ends of nesprin-1/-2 giant are integrated at the nuclear surface: via the C-terminal KASH-domain and the N-terminal ABD-nesprin-3 association. Interestingly, nesprin-2 ABD or KASH-domain overexpression leads to increased nuclear areas. Conversely, nesprin-2 mini (contains the ABD and KASH-domain but lacks the massive nesprin-2 giant rod segment) expression yields smaller nuclei. Nuclear shrinkage is further enhanced upon nesprin-3 co-expression or microfilament depolymerization. Our findings suggest that multivariate intermolecular nesprin interactions with the cytoskeleton form a lattice-like filamentous network covering the outer nuclear membrane, which determines nuclear size.