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Background: The mechanism of microbiota assembly is one of the main problems in microbiome research, which is also the primary theoretical basis for precise manipulation of microbial communities. Bacterial quorum sensing (QS), as the most common means for bacteria to exchange information and interactions, is characterized by universality, specificity, and regulatory power, which therefore may influence the assembly processes of human microbiota. However, the regulating role of QS in microbiota assembly is rarely reported. In this study, we developed an optimized in vitro oral biofilm microbiota assembling (OBMA) model to simulate the time-series assembly of oral biofilm microbiota (OBM), by which to excavate the QS network and its regulating power in the process., Results: By using the optimized OBMA model, we were able to restore the assembly process of OBM and generate time-series OBM metagenomes of each day. We discovered a total of 2291 QS protein homologues related to 21 QS pathways. Most of these pathways were newly reported and sequentially enriched during OBM assembling. These QS pathways formed a comprehensive longitudinal QS network that included successively enriched QS hubs, such as Streptococcus, Veillonella-Megasphaera group, and Prevotella-Fusobacteria group, for information delivery. Bidirectional cross-talk among the QS hubs was found to play critical role in the directional turnover of microbiota structure, which in turn, influenced the assembly process. Subsequent QS-interfering experiments accurately predicted and experimentally verified the directional shaping power of the longitudinal QS network in the assembly process. As a result, the QS-interfered OBM exhibited delayed and fragile maturity with prolonged membership of Streptococcus and impeded membership of Prevotella and Fusobacterium., Conclusion: Our results revealed an unprecedented longitudinal QS network during OBM assembly and experimentally verified its power in predicting and manipulating the assembling process. Our work provides a new perspective to uncover underlying mechanism in natural complex microbiota assembling and a theoretical basis for ultimately precisely manipulating human microbiota through intervention in the QS network. Video Abstract., (© 2023. The Author(s).)

Objective: To assess the clinical value of multi-detector computed tomography (MDCT) source image on detecting extracoronary abnormalities in a large cohort of patients with suspected coronary artery disease (CAD)., Method: MDCT source images from 3240 consecutive patients (mean 64.5 years) with suspected CAD were reviewed retrospectively by 2 readers.Extra-coronary findings were classified according to involved organ and level of clinical significance.Following organs were examined:lungs, upper abdomen, spine, chest wall, mediastinum and vascularatures. Clinical relevance of extracoronary findings was considered as either "significant" or "non-significant"."Significant" findings were subclassified as score 1:findings necessitating immediate therapeutic actions, or score 2:findings with uncertain clinical or prognostic relevance, requiring clinical awareness, follow-up or further investigations (non-urgent)."Non-significant" findings were assigned to score 3:findings without clinical implication. The irrelevant incidental findings (e.g. spinal degenerative changes, aortic calcification) were not analyzed., Results: Extracoronary findings was evidenced in 330 patients with 424 abnormalities, 20.3% (67/330) patients had multiple lesions, 16.5% lesions were located in the lungs, 13.2% lesions found in the upper abdomen, 56.8% (241/424) lesions evidenced in the mediastinum,0.9% (4/424) lesions seen in the spine and chest wall, 13.9% (53/424) lesions were related to other vascular disease. Pleural effusion accounts for 5.5% of the mediastinum lesions.Incidence of heart cavity enlargement, heart valve disease, pericardial effusion/calcification, atrial/ventricular perfusion defects, myocardial disease, congenital heart disease, ventricular aneurysm was 14.7% (56/380), 15.5% (59/380), 10.8% (41/380), 3.9% (15/380), 0.8% (3/380), 1.6% (6/380), and 1.8% (7/380) respectively. The clinical significance score 1-3 was 8.5% (36/424) , 81.1% (344/424) , and 10.4% (44/424) respectively.Incidence of detected extracoronary findings was the highest by bone window and the lowest by lung window.Incidence of extracoronary findings was not related to CAD (χ2 = 81.76, C = 0.155, P > 0.05).Inter-reader agreement on extracoronary findings was excellent (Kappa = 0.934, P > 0.05)., Conclusion: Our data show that it is of clinical value to observe and report extracoronary findings with source image of cardiac MDCT.