The Salivary Mycobiome Contains 2 Ecologically Distinct Mycotypes.

A broad range of fungi has been detected in molecular surveys of the oral mycobiome. However, knowledge is still lacking on interindividual variability of these communities and the ecologic and clinical significance of oral fungal commensals. In this cross-sectional study, we use internal transcribed spacer 1 amplicon sequencing to evaluate the salivary mycobiome in 59 subjects, 36 of whom were scheduled to receive cancer chemotherapy. Analysis of the broad population structure of fungal communities in the whole cohort identified 2 well-demarcated genus-level community types (mycotypes), with Candida and Malassezia as the main taxa driving cluster partitioning. The Candida mycotype had lower diversity than the Malassezia mycotype and was positively correlated with cancer and steroid use in these subjects, smoking, caries, utilizing a removable prosthesis, and plaque index. Mycotypes were also associated with metabolically distinct bacteria indicative of divergent oral environments, with aciduric species enriched in the Candida mycotype and inflammophilic bacteria increased in the Malassezia mycotype. Similar to their fungal counterparts, coexisting bacterial communities associated with the Candida mycotype showed lower diversity than those associated with the Malassezia mycotype, suggesting that common environmental pressures affected bacteria and fungi. Mycotypes were also seen in an independent cohort of 24 subjects, in which cultivation revealed Malassezia as viable oral mycobiome members, although the low-abundance Malassezia sympodialis was the only Malassezia species recovered. There was a high degree of concordance between the molecular detection and cultivability of Candida, while cultivation showed low sensitivity for detection of the Malassezia mycotype. Overall, our work provides insights into the oral mycobiome landscape, revealing 2 community classes with apparently distinct ecologic constraints and specific associations with coexisting bacteria and clinical parameters. The utility of mycotypes as biomarkers for oral diseases warrants further study.

Clinical, Immune, and Microbiome Traits of Gingivitis and Peri-implant Mucositis.

Tissues surrounding dental implants and teeth develop clinical inflammation in response to microbial stimuli. However, the literature suggests that differences exist in the microbial insult and inflammatory responses leading to gingivitis and peri-implant mucositis. In this pilot study, the authors use for the first time a systems biology approach to comprehensively evaluate clinical parameters, selected inflammatory markers, and the microbiome of subject-matched tooth and implant sites during native inflammation and in response to experimental plaque accumulation. Fifteen subjects with 2 posterior implants and corresponding contralateral teeth were examined at enrollment; at day 0, after reinstitution of gingival/mucosal health; at days 7, 14, and 21, during stent-mediated oral hygiene (OH) abstention; and at day 42, after resumption of OH. The subgingival microbiome was evaluated via 16S rRNA gene sequencing and 8 selected inflammatory markers measured in crevicular fluid. Comparison of teeth and implants via general linear models based on orthogonal polynomials showed similar responses in clinical parameters, inflammatory mediators, and proportions of individual microbial taxa during OH abstention. Implants, however, accumulated less plaque and underwent more heterogeneous shifts in microbiome structure. A multilevel, within-group, sparse partial least squares analysis of covariation of microbial, inflammatory, and clinical parameters throughout all study visits found inflammation around teeth and implants positively correlated with IL-1 alpha and IL-1 beta and with the proportions of Selenomonas, Prevotella, and 5 species-level phylotypes. Gingivitis, however, showed a stronger positive correlation with lactoferrin and IL-1ra and a stronger negative correlation with Rothia. Peri-implant mucositis, on the contrary, correlated positively with certain microbial taxa not associated with gingivitis by a previous study or the current one. In summary, differences existed between implants and tooth sites in microbiome evolution during OH abstention and in the correlation of specific inflammatory mediators and microbial taxa with clinical inflammation. Common biological features, however, were also identified for gingivitis and mucositis.

Effects of joint effusion on proprioception in patients with knee osteoarthritis: a single-blind, randomized controlled clinical trial.

OBJECTIVE: To assess the effects of joint effusion on proprioceptive status in patients with knee osteoarthritis (OA). DESIGN: A single-blind, randomized, controlled clinical trial in 40 female subjects aged 50 years and over with painful knee OA. All subjects were randomly assigned to either the control or experimental group. A volume of 20 mL of normal saline was injected into the knee joint cavity of subjects in the experimental group under ultrasonographic guidance. Proprioceptive acuity was assessed by active repositioning of the lower limb using an electrogoniometer to measure knee joint position sense (JPS) under both non-weight-bearing (NWB) and weight-bearing (WB) conditions twice, with a 20-min rest interval. The experimental group performed the task twice (Test 1 and Test 2) before and within 5 min after joint infusion. The control group also performed Test 1 and Test 2 without joint infusion. The outcome of interest was the absolute angular error (AAE), ignoring the direction of the error, between the randomized target angle and the patient's reproduced angle of JPS values. RESULTS: Compared with the control group, JPS was significantly compromised in the experimental group in the NWB test after joint infusion (P=0.025). However, no significant differences in the angular error were observed between Test 1 and Test 2 in the control group for the NWB or WB test or in the experimental group for the WB test after infusion (P>0.05). CONCLUSIONS: This study showed that joint effusion impairs proprioceptive function in osteoarthritic knee joints.