High-performing cross-dataset machine learning reveals robust microbiota alteration in secondary apical periodontitis.

Multiple research groups have consistently underscored the intricate interplay between the microbiome and apical periodontitis. However, the presence of variability in experimental design and quantitative assessment have added a layer of complexity, making it challenging to comprehensively assess the relationship. Through an unbiased methodological refinement analysis, we re-analyzed 4 microbiota studies including 120 apical samples from infected teeth (with/without root canal treatment), healthy teeth, using meta-analysis and machine learning. With high-performing machine-learning models, we discover disease signatures of related species and enriched metabolic pathways, expanded understanding of apical periodontitis with potential therapeutic implications. Our approach employs uniform computational tools across datasets to leverage statistical power and define a reproducible signal potentially linked to the development of secondary apical periodontitis (SAP).

Metabolomics reveals high fructose-1,6-bisphosphate from fluoride-resistant Streptococcus mutans.

BACKGROUND: Fluoride-resistant Streptococcus mutans (S. mutans) strains have developed due to the wide use of fluoride in dental caries prevention. However, the metabolomics of fluoride-resistant S. mutans remains unclear. OBJECTIVE: This study aimed to identify metabolites that discriminate fluoride-resistant from wild-type S. mutans. MATERIALS AND METHODS: Cell supernatants from fluoride-resistant and wild-type S. mutans were collected and analyzed by liquid chromatography-mass spectrometry. Principal components analysis and partial least-squares discriminant analysis were performed for the statistical analysis by variable influence on projection (VIP > 2.0) and p value (Mann-Whitney test, p < 0.05). Metabolites were assessed qualitatively using the Human Metabolome Database version 2.0 ( http://www.hmdb.ca ), or Kyoto Encyclopedia of Genes and Genomes ( http://www.kegg.jp ), and Metaboanalyst 6.0 ( https://www.metaboanalyst.ca ). RESULTS: Fourteen metabolites differed significantly between fluoride-resistant and wild-type strains in the early log phase. Among these metabolites, 5 were identified. There were 32 differential metabolites between the two strains in the stationary phase, 13 of which were identified. The pyrimidine metabolism for S. mutans FR was matched with the metabolic pathway. CONCLUSIONS: The fructose-1,6-bisphosphate concentration increased in fluoride-resistant strains under acidic conditions, suggesting enhanced acidogenicity and acid tolerance. This metabolite may be a promising target for elucidating the cariogenic and fluoride resistant mechanisms of S. mutans.

Residents' KABP and Social Support Statuses Under Normalized COVID-19 Pandemic Prevention and Control: A Cross-Sectional Study.

OBJECTIVES: To investigate the status quo of residents' knowledge, attitude, belief, and practice (KABP) and social support and the correlation of KABP with social support under normalized coronavirus disease (COVID-19) pandemic prevention and control. METHODS: A questionnaire was designed based on the KABP model, and an online survey was conducted among residents in September 2022. SPSS software (version 25.0) was used to analyze the data. Two independent sample t-tests, one-way analysis of variance (ANOVA), multivariate linear regression analysis, and Pearson's correlation analysis were conducted. RESULTS: In total, 326 valid questionnaires were obtained. The scoring rates of residents' KABP and social support were 68.1%, 92.2%, 89.3%, 75.3%, and 62.6%, respectively. Main factors influencing residents' knowledge included gender, nationality, education level, practice, and social support; those influencing attitude were belief and practice; those influencing belief were place of residence, attitude, and practice; those influencing practice were knowledge, attitude, belief, and social support; and those influencing social support were marital status, place of residence, knowledge, and practice. Social support was positively correlated with knowledge and practice. CONCLUSIONS: This study provides a scientific foundation for the current normalized prevention and control of COVID-19 and is conducive to health managers to better carry out prevention and control related health education for specific groups.

Attitude and influencing factors to receive the COVID-19 vaccine among university students in Sichuan Province, China: A cross-sectional study.

AIMS: To explore the university students' attitude and the potential influencing factors to receive the coronavirus disease 2019 (COVID-19) vaccine in Sichuan Province, China. DESIGN: A cross-sectional study. METHODS: The self-designed questionnaire was distributed among university students online in June 2021. SPSS software was used for statistical analysis of the data. Descriptive statistics, Chi-square, two independent samples t-tests, one-way analysis of variance (ANOVA), multivariate linear regression, and content analysis were performed. RESULTS: A total of 397 questionnaires were analysed, involving 316 (79.6%) respondents have received at least one dose of a COVID-19 vaccine and 81 (20.4%) have not taken the vaccine. The total mean score of university students' vaccination attitude was 25.97 (standard deviation [SD] = 3.720), and the total scoring rate was 74.2%. Main factors influencing students' attitude included education level, major, living style, with chronic disease or not, self-reported vaccination status, and number of medical units that can provide vaccination within 3 km of residence. Students were more willing to choose Chinese-manufactured vaccines (66.8%) and participate in collective vaccination programs organized by the school (71.3%). The desired vaccine protection period was 5-10 years (42.1%). The top three reasons for refusing the vaccine or vaccine hesitancy were as follows: concern about the side effects of vaccine (44.8%), lack of information about vaccine (31.0%), and concern about the efficacy of vaccine (29.3%). CONCLUSION: In general, most of the participants had relatively high level of positive attitude to receive the COVID-19 vaccine. Nevertheless, more attention should be paid to postgraduate students, non-medical students, those living alone, those with chronic disease, those have not received the COVID-19 vaccine, and those living far away from the vaccination medical units. Findings of this study can help educational institutions in developing effective interventions to improve the vaccination rate in the university student population.

Borate bioactive glass prevents zoledronate-induced osteonecrosis of the jaw by restoring osteogenesis and angiogenesis.

OBJECTIVES: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a severe complication of systemic nitrogen-containing bisphosphonate (N-BP) administration, which leads to osteonecrosis, pain, and infection. Despite much effort, effective remedies are yet to be established. This study aimed to investigate potential recovery effect of borate bioactive glass (BBG) in vitro and in vivo. METHODS: The effect of BBG on zoledronate-treated bone marrow mesenchymal cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) was explored by cell counting kit-8, EdU assay, flow cytometry, alkaline phosphatase staining, alizarin red staining, angiogenesis experiment, and real-time quantitative polymerase chain reaction. The preventive effect of BBG on zoledronate-induced osteonecrosis of the jaw in rat model was examined by micro-CT, HE staining, and immunohistochemistry. RESULTS: Exposure of BBG to BMSCs and HUVECs increased cell proliferation and restored their osteogenesis and angiogenesis potential in vitro. The BRONJ lesions were satisfactorily repaired and bone mineral density, bone volume/tissue volume, trabecula number, OCN-positive cells, and CD31-positive cells were increased in the BBG-treated groups compared with saline-treated groups. CONCLUSIONS: Exposure of BMSCs and HUVECs to BBG restores osteogenesis and angiogenesis inhibited by zoledronate. BBG successfully restores extraction socket healing of BRONJ in rat model.

[Effect of zoladronate on the proliferation and osteogenic differentiation of rat bone mesenchymal stem cells].

OBJECTIVE: To evaluate the effect of zoledronate acid (ZA) on the proliferation and osteogenic differentiation of rat mesenchymal stem cells (BMSCs). METHODS: The BMSCs isolated from the SD rats were cultured with different concentrations of ZA (1, 5, 10, and 20 µmol·L), and the contro1 group received the same volume of culture medium but without ZA. Cell counting kit-8 was used to detect proliferation activity in each group. Alkaline phosphatase (ALP) staining and alizarin red staining were used to detect the osteogenic differentiation ability in each group. The gene expression levels of ALP, bone morphogenetic protein-2 (BMP-2), typeⅠcollagenase (COL-Ⅰ), runt-related transcription factor-2 (Runx-2), zinc finger structure transcription factor (Osx), osteocalcin (OCN), and osteopontin (OPN) were evaluated by real-time quantitative polymerase chain reaction (qRT-PCR). RESULTS: Zoledronate at 1 µmol·L⁻¹ concentration had no effect on the proliferation and osteogenic differentiation of BMSCs. No significant difference was observed between this group and the control group (P>0.05). When the ZA concentration was more than 1 µmol·L⁻¹, ZA inhibited the proliferation and osteogenic differentiation of BMSCs, and the effect was concentration dependent. The difference between each group and the control group was statistically significant (P<0.05). At ZA concentration of 5 µmol·L⁻¹, ZA enhanced the expression of ALP, BMP-2, COL-Ⅰ, Runx-2, Osx, OCN, and OPN (P<0.05). However, at ZA concentration of more than 5 µmol·L⁻¹, the expression levels of osteogenicrelated genes in each group was lower than those of the control group (P<0.05). CONCLUSIONS: Low ZA concentration has no effect on the proliferation and osteogenic differentiation of BMSCs. ZA at 5 µmol·L⁻¹ concentration inhibits the proliferation but promotes the osteogenic differentiation of BMSCs. High ZA concentration inhibits the proliferation and osteogenic differentiation of BMSCs.