Journal of Oral Microbiology最新文献

{"title":"Structural and antigenic characterization of a novel genotype of Mfa1 fimbriae in <i>Porphyromonas gingivalis</i>.","authors":"Miyuna Fujimoto,&nbsp;Yoshikazu Naiki,&nbsp;Kotaro Sakae,&nbsp;Tomohiko Iwase,&nbsp;Naoyoshi Miwa,&nbsp;Keiji Nagano,&nbsp;Hiroyuki Nawa,&nbsp;Yoshiaki Hasegawa","doi":"10.1080/20002297.2023.2215551","DOIUrl":"https://doi.org/10.1080/20002297.2023.2215551","url":null,"abstract":"<p><strong>Background: </strong>Mfa1 fimbriae of the periodontal pathogen Porphyromonas gingivalis are responsible for biofilm formation and comprise five proteins: Mfa1-5. Two major genotypes, mfa1⁷⁰ and mfa1⁵³, encode major fimbrillin. The mfa1⁷⁰ genotype is further divided into the mfa1^70A and mfa1^70B subtypes. The properties of the novel mfa1^70B remain unclear.</p><p><strong>Methods: </strong>Fimbriae were purified from P. gingivalis strains JI-1 (mfa1^70A), 1439 (mfa1^70B), and Ando (mfa1⁵³), and their components and their structures were analyzed. Protein expression and variability in the antigenic specificity of fimbrillins were compared using Coomassie staining and western blotting using polyclonal antibodies against Mfa1^70A, Mfa1^70B, and Mfa1⁵³ proteins. Cell surface expression levels of fimbriae were analyzed by filtration enzyme-linked immunosorbent assays.</p><p><strong>Results: </strong>The composition and structures of the purified Mfa1 fimbriae of 1439 was similar to that of JI-1. However, each Mfa1 protein of differential subtype/genotype was specifically detected by western blotting. Mfa1^70B fimbriae were expressed in several strains such as 1439, JKG9, B42, 1436, and Kyudai-3. Differential protein expression and antigenic heterogeneities were detected in Mfa2-5 between strains.</p><p><strong>Conclusion: </strong>Mfa1 fimbriae from the mfa170A and mfa170B genotypes indicated an antigenic difference suggesting the mfa170B, is to be utilized for the novel classification of P. gingivalis.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2215551"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10201998/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10563940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Profiles of oral microbiome associated with nasogastric tube feeding.","authors":"Ding-Han Wang,&nbsp;Fa-Tzu Tsai,&nbsp;Hsi-Feng Tu,&nbsp;Cheng-Chieh Yang,&nbsp;Ming-Lun Hsu,&nbsp;Lin-Jack Huang,&nbsp;Chiu-Tzu Lin,&nbsp;Wun-Eng Hsu,&nbsp;Yu-Cheng Lin","doi":"10.1080/20002297.2023.2200898","DOIUrl":"https://doi.org/10.1080/20002297.2023.2200898","url":null,"abstract":"<p><strong>Background: </strong>Dysbiosis of oral microbiome causes chronic diseases including dental caries and periodontitis, which frequently affect older patient populations. Severely disabled individuals with impaired swallowing functions may require nutritional supply via nasogastric (NG) tubes, further impacting their oral condition and possibly microbial composition. However, little is known about the effect of NG tube on oral microbes and its potential ramification.</p><p><strong>Methods: </strong>By using 16S rRNA amplicon sequencing, we characterized the tongue microbiome of 27 patients fed with NG tubes and 26 others fed orally.</p><p><strong>Results: </strong>The microbial compositions of NG-tube and oral-feeding patients were substantially different, with more Gram-negative aerobes enriched in the presence of NG tube. Specifically, NG-tube patients presented more opportunistic pathogens like <i>Pseudomonas</i> and <i>Corynebacterium</i> associated with pneumonia and lower levels of commensal <i>Streptococcus</i> and <i>Veillonella</i>. Co-occurrence analysis further showed an inverse relationship between commensal and pathogenic species.</p><p><strong>Conclusion: </strong>We present a systematic, high-throughput profiling of oral microbiome with regard to long-term NG tube feeding among the older patient population.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2200898"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/48/1e/ZJOM_15_2200898.PMC10101675.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9685855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanisms of <i>Porphyromonas gingivalis</i> to translocate over the oral mucosa and other tissue barriers.","authors":"Caroline A de Jongh,&nbsp;Teun J de Vries,&nbsp;Floris J Bikker,&nbsp;Susan Gibbs,&nbsp;Bastiaan P Krom","doi":"10.1080/20002297.2023.2205291","DOIUrl":"https://doi.org/10.1080/20002297.2023.2205291","url":null,"abstract":"<p><strong>Introduction: </strong>The oral pathogen <i>Porphyromonas gingivalis</i> is not only associated with periodontitis but also with systemic diseases elsewhere in the body. The mechanisms by which <i>P. gingivalis</i> travels from the oral cavity to other organs in the body are largely unknown. This review describes the four putative mechanisms supported by experimental evidence, which enable translocation of <i>P. gingivalis</i> over the oral mucosa, endothelial barriers and subsequent dissemination into the bloodstream.</p><p><strong>Mechanisms: </strong>The first mechanism: proteolytic enzymes secreted by <i>P. gingivalis</i> degrade adhesion molecules between tissue cells, and the extracellular matrix. This weakens the structural integrity of the mucosa and allows <i>P</i>. <i>gingivalis</i> to penetrate the tissue. The second is transcytosis: bacteria actively enter tissue cells and transfer to the next layer or the extracellular space. By travelling from cell to cell, <i>P. gingivalis</i> reaches deeper structures. Thirdly, professional phagocytes take up <i>P. gingivalis</i> and travel to the bloodstream where <i>P. gingivalis</i> is released. Lastly, <i>P. gingivalis</i> can adhere to the hyphae forming Candida albicans. These hyphae can penetrate the mucosal tissue, which may allow <i>P. gingivalis</i> to reach deeper structures.</p><p><strong>Conclusion: </strong>More research could elucidate targets to inhibit <i>P. gingivalis</i> dissemination and prevent the onset of various systemic diseases.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2205291"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10134951/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9393397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exopolysaccharides metabolism and cariogenesis of <i>Streptococcus mutans</i> biofilm regulated by antisense <i>vicK</i> RNA.","authors":"Yuting Sun,&nbsp;Hong Chen,&nbsp;Mengmeng Xu,&nbsp;Liwen He,&nbsp;Hongchen Mao,&nbsp;Shiyao Yang,&nbsp;Xin Qiao,&nbsp;Deqin Yang","doi":"10.1080/20002297.2023.2204250","DOIUrl":"https://doi.org/10.1080/20002297.2023.2204250","url":null,"abstract":"<p><strong>Background: </strong><i>Streptococcus mutans</i> (<i>S.</i> <i>mutans</i>) is a pivotal cariogenic pathogen contributing to its multiple virulence factors, one of which is synthesizing exopolysaccharides (EPS). VicK, a sensor histidine kinase, plays a major role in regulating genes associated with EPS synthesis and adhesion. Here we first identified an antisense <i>vicK</i> RNA (AS<i>vicK</i>) bound with <i>vicK</i> into double-stranded RNA (dsRNA).</p><p><strong>Objective: </strong>This study aims to investigate the effect and mechanism of AS<i>vicK</i> in the EPS metabolism and cariogenesis of <i>S. mutans</i>.</p><p><strong>Methods: </strong>The phenotypes of biofilm were detected by scanning electron microscopy (SEM), gas chromatography-mass spectrometery (GC-MS) , gel permeation chromatography (GPC) , transcriptome analysis and Western blot. Co-immunoprecipitation (Co-ip) assay and enzyme activity experiment were adopted to investigate the mechanism of AS<i>vicK</i> regulation. Caries animal models were developed to study the relationship between AS<i>vicK</i> and cariogenicity of <i>S. mutans.</i></p><p><strong>Results: </strong>Overexpression of AS<i>vicK</i> can inhibit the growth of biofilm, reduce the production of EPS and alter genes and protein related to EPS metabolism. AS<i>vicK</i> can adsorb RNase III to regulate <i>vicK</i> and affect the cariogenicity of <i>S. mutans</i>.</p><p><strong>Conclusions: </strong>AS<i>vicK</i> regulates <i>vicK</i> at the transcriptional and post-transcriptional levels, effectively inhibits EPS synthesis and biofilm formation and reduces its cariogenicity <i>in</i> <i>vivo</i>.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2204250"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/f1/67/ZJOM_15_2204250.PMC10150615.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9416259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial oral lavage reduces the SARS-CoV-2 load in intubated patients: randomized clinical trial.","authors":"Letícia Mello Bezinelli,&nbsp;Luciana Corrêa,&nbsp;Stephany Beyerstedt,&nbsp;Érika Bevilaqua Rangel,&nbsp;Carlos Benitez,&nbsp;Nelson Hamerschlak,&nbsp;João Renato Rebello Pinho,&nbsp;Debora Heller,&nbsp;Fernanda de Paula Eduardo","doi":"10.1080/20002297.2022.2152179","DOIUrl":"https://doi.org/10.1080/20002297.2022.2152179","url":null,"abstract":"<p><strong>Background: </strong>The oral cavity can be a reservoir for SARS-CoV-2 and may play a crucial role in the viral transmission in the hospital environment.</p><p><strong>Objective: </strong>To investigate whether an oral hygiene protocol with chlorhexidine (CHX) used alone and in combination with hydrogen peroxide (HP) in the intensive care unit was effective in reducing the SARS-CoV-2 viral load in the oral cavity.</p><p><strong>Methods: </strong>SARS-CoV-2 viral load was measured on oral fluid samples collected from patients undergoing orotracheal intubation. The study sample was randomly in: CHX group (n = 19) - oral rinse using only 0.12% CHX solution; HP+CHX group (n = 24) - oral rinse with 1.5% HP and 0.12% CHX. The samples were collected before the interventions (T0), immediately (T1), 30 minutes (T2) and 60 minutes (T3) after the procedure.</p><p><strong>Results: </strong>A significant viral load reduction was observed at T1 (mean ± SD:-0.57 ± 0.19 log10;-73.2%;p = 0.022) in the HP+CHX group. No statistically significant differences between any time points were observed in the CHX group.</p><p><strong>Conclusion: </strong>The HP+CHX oral rinses significantly reduced the SARS-CoV-2 viral load in the oral fluid immediately after the procedure. The CHX oral rinse alone did not result in any significant viral load reductions.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2152179"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10161956/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9799442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploration of the interplay between spatially distinct microbial habitats through comparative analysis.","authors":"Hyunji Kim,&nbsp;Jin-Sil Hong,&nbsp;Pil-Young Yun,&nbsp;Kyung-Gyun Hwang,&nbsp;Keun-Suh Kim,&nbsp;Hyo-Jung Lee,&nbsp;Kyoung Un Park","doi":"10.1080/20002297.2023.2229693","DOIUrl":"https://doi.org/10.1080/20002297.2023.2229693","url":null,"abstract":"<p><strong>Objectives: </strong>The oral microbiome is closely associated with systemic diseases, indicating the presence of bacteremia and inflammatory mediators in the systemic circulation. Our research aims to investigate the relationship between the oral microbiome and other microbial habitats.</p><p><strong>Methods: </strong>We analyzed 180 specimens from 36 patients, including saliva, buccal swab, plaque, stool, and blood samples from a healthy group (Non_PD, <i>n</i> = 18) and a periodontitis group (PD, <i>n</i> = 18). The final analysis included 147 specimens, with varying sample sizes for each group. Metagenomic analysis was performed using prokaryotic 16S rRNA on the MiSeq platform (Illumina).</p><p><strong>Results: </strong>PD saliva showed significant richness differences (P's < 0.05), similar to plaque. Buccal swabs had slight variations. Microbial network analysis revealed altered microbial interactions in the PD group, with decreased interactions in saliva and buccal swabs, and increased interactions in plaque. In our analysis of nine specimens where all paired habitat samples could be analyzed, microorganisms linked to oral periodontitis were found in sterile blood samples, resembling the oral cavity's composition.</p><p><strong>Conclusions: </strong>Microbiome differences should consider overall microbial-environment interactions, alongside diversity and richness. Our data cautiously suggest that disease-related changes in the salivary microbiome may be reflected in blood specimens through the oral-blood axis.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2229693"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/04/61/ZJOM_15_2229693.PMC10308874.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10196642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Targeting cariogenic pathogens and promoting competitiveness of commensal bacteria with a novel pH-responsive antimicrobial peptide.","authors":"Wentao Jiang,&nbsp;Zhuo Xie,&nbsp;Shuheng Huang,&nbsp;Qiting Huang,&nbsp;Lingling Chen,&nbsp;Xianling Gao,&nbsp;Zhengmei Lin","doi":"10.1080/20002297.2022.2159375","DOIUrl":"https://doi.org/10.1080/20002297.2022.2159375","url":null,"abstract":"<p><p>Novel ecological antimicrobial approaches to dental caries focus on inhibiting cariogenic pathogens while enhancing the growth of health-associated commensal communities or suppressing cariogenic virulence without affecting the diversity of oral microbiota, which emphasize the crucial role of establishing a healthy microbiome in caries prevention. Considering that the acidified cariogenic microenvironment leads to the dysbiosis of microecology and demineralization of enamel, exploiting the acidic pH as a bioresponsive trigger to help materials and medications target cariogenic pathogens is a promising strategy to develop novel anticaries approaches. In this study, a pH-responsive antimicrobial peptide, LH12, was designed utilizing the pH-sensitivity of histidine, which showed higher cationicity and stronger interactions with bacterial cytomembranes at acidic pH. <i>Streptococcus mutans</i> was used as the <i>in vitro</i> caries model to evaluate the inhibitory effects of LH12 on the cariogenic properties, such as biofilm formation, biofilm morphology, acidurance, acidogenicity, and exopolysaccharides synthesis. The dual-species model of <i>Streptococcus mutans</i> and <i>Streptococcus gordonii</i> was established <i>in vitro</i> to evaluate the regulation effects of LH12 on the mixed species microbial community containing both cariogenic bacteria and commensal bacteria. LH12 suppressed the cariogenic properties and regulated the bacterial composition to a healthier condition through a dual-functional mechanism. Firstly, LH12-targeted cariogenic pathogens in response to the acidified microenvironment and suppressed the cariogenic virulence by inhibiting the expression of multiple virulence genes and two-component signal transduction systems. Additionally, LH12 elevated H₂O₂ production of the commensal bacteria and subsequently improved the ecological competitiveness of the commensals. The dual-functional mechanism made LH12 a potential bioresponsive approach to caries management.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2159375"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9788686/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10440649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Orofacial clefts alter early life oral microbiome maturation towards higher levels of potentially pathogenic species: A prospective observational study.","authors":"Corinna L Seidel,&nbsp;Karin Strobel,&nbsp;Matthias Weider,&nbsp;Marco Tschaftari,&nbsp;Christoph Unertl,&nbsp;Ines Willershausen,&nbsp;Manuel Weber,&nbsp;André Hoerning,&nbsp;Patrick Morhart,&nbsp;Michael Schneider,&nbsp;Matthias W Beckmann,&nbsp;Christian Bogdan,&nbsp;Roman G Gerlach,&nbsp;Lina Gölz","doi":"10.1080/20002297.2022.2164147","DOIUrl":"https://doi.org/10.1080/20002297.2022.2164147","url":null,"abstract":"<p><p>Orofacial clefts (OFC) present different phenotypes with a postnatal challenge for oral microbiota development. In order to investigate the impact of OFC on oral microbiota, smear samples from 15 neonates with OFC and 17 neonates without OFC were collected from two oral niches (tongue, cheek) at two time points, i.e. after birth (T0: Ø3d OFC group; Ø2d control group) and 4-5 weeks later (T1: Ø32d OFC group; Ø31d control group). Subsequently, the samples were analyzed using next-generation sequencing. We detected a significant increase of alpha diversity and <i>anaerobic</i> and <i>Gram-negative species</i> from T0 to T1 in both groups. Further, we found that at T1 OFC neonates presented a significantly lower alpha diversity (lowest values for high cleft severity) and significantly higher levels of <i>Enterobacteriaceae (Citrobacter, Enterobacter, Escherichia-Shigella, Klebsiella), Enterococcus, Bifidobacterium, Corynebacterium, Lactocaseibacillus, Staphylococcus, Acinetobacter</i> and <i>Lawsonella</i> compared to controls. Notably, neonates with unilateral and bilateral cleft lip and palate (UCLP/BCLP) presented similarities in beta diversity and a mixture with skin microbiota. However, significant differences were seen in neonates with cleft palate only compared to UCLP/BCLP with higher levels of <i>anaerobic species</i>. Our findings revealed an influence of OFC as well as cleft phenotype and severity on postnatal oral microbiota maturation.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2164147"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9828641/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10522719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SARS-CoV-2 RT-qPCR Ct values in saliva and nasopharyngeal swab samples for disease severity prediction.","authors":"Kristina Snipaitiene,&nbsp;Birute Zablockiene,&nbsp;Rasa Sabaliauskaite,&nbsp;Kristina Zukauskaite,&nbsp;Elzbieta Matulyte,&nbsp;Tautvile Smalinskaite,&nbsp;Mindaugas Paulauskas,&nbsp;Rolandas Zablockis,&nbsp;Mantvydas Lopeta,&nbsp;Julius Gagilas,&nbsp;Alina Puriene,&nbsp;Ligita Jancoriene,&nbsp;Sonata Jarmalaite","doi":"10.1080/20002297.2023.2213106","DOIUrl":"https://doi.org/10.1080/20002297.2023.2213106","url":null,"abstract":"<p><strong>Background: </strong>Comparison of clinical value of RT-qPCR-based SARS-CoV-2 tests performed on saliva samples (SSs) and nasopharyngeal swab samples (NPSs) for prediction of the COVID-19 disease severity.</p><p><strong>Methods: </strong>Three paired SSs and NPSs collected every 3 days from 100 hospitalised COVID-19 patients during 2020 Jul-2021 Jan were tested by RT-qPCR for the original SARS-CoV-2 virus and compared to 150 healthy controls. Cases were divided into mild+moderate (Cohort I, <i>N</i> = 47) and severe disease (Cohort II, <i>N</i> = 53) cohorts and compared.</p><p><strong>Results: </strong>SARS-CoV-2 was detected in 65% (91/140) vs. 53% (82/156) of NPSs and 49% (68/139) vs. 48% (75/157) of SSs collected from Cohort I and II, respectively, resulting in the total respective detection rates of 58% (173/296) vs. 48% (143/296) (<i>P</i> = 0.017). Ct values of SSs were lower than those of NPSs (mean Ct = 28.01 vs. 30.07, <i>P</i> = 0.002). Although Ct values of the first SSs were significantly lower in Cohort I than in Cohort II (<i>P</i> = 0.04), it became negative earlier (mean 11.7 vs. 14.8 days, <i>P</i> = 0.005). Multivariate Cox proportional hazards regression analysis showed that Ct value ≤30 from SSs was the independent predictor for severe COVID-19 (HR = 10.06, 95% CI: 1.84-55.14, <i>P</i> = 0.008).</p><p><strong>Conclusion: </strong>Salivary RT-qPCR testing is suitable for SARS-CoV-2 infection control, while simple measurement of Ct values can assist in prediction of COVID-19 severity.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2213106"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10193917/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10195632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulatory mechanisms of exopolysaccharide synthesis and biofilm formation in Streptococcus mutans.","authors":"Ting Zheng,&nbsp;Meiling Jing,&nbsp;Tao Gong,&nbsp;Jiangchuan Yan,&nbsp;Xiaowan Wang,&nbsp;Mai Xu,&nbsp;Xuedong Zhou,&nbsp;Jumei Zeng,&nbsp;Yuqing Li","doi":"10.1080/20002297.2023.2225257","DOIUrl":"https://doi.org/10.1080/20002297.2023.2225257","url":null,"abstract":"<p><strong>Background: </strong>Dental caries is a chronic, multifactorial and biofilm-mediated oral bacterial infection affecting almost every age group and every geographical region. <i>Streptococcus mutans</i> is considered an important pathogen responsible for the initiation and development of dental caries. It produces exopolysaccharides <i>in situ</i> to promote the colonization of cariogenic bacteria and coordinate dental biofilm development.</p><p><strong>Objective: </strong>The understanding of the regulatory mechanism of <i>S. mutans</i> biofilm formation can provide a theoretical basis for the prevention and treatment of caries.</p><p><strong>Design: </strong>At present, an increasing number of studies have identified many regulatory systems in <i>S. mutans</i> that regulate biofilm formation, including second messengers (e.g. c-di-AMP, Ap4A), transcription factors (e.g. EpsR, RcrR, StsR, AhrC, FruR), two-component systems (e.g. CovR, VicR), small RNA (including sRNA0426, srn92532, and srn133489), acetylation modifications (e.g. ActG), CRISPR-associated proteins (e.g. Cas3), PTS systems (e.g. EIIAB), quorum-sensing signaling system (e.g. LuxS), enzymes (including Dex, YidC, CopZ, EzrA, lmrB, SprV, RecA, PdxR, MurI) and small-molecule metabolites.</p><p><strong>Results: </strong>This review summarizes the recent progress in the molecular regulatory mechanisms of exopolysaccharides synthesis and biofilm formation in <i>S. mutans</i>.</p>","PeriodicalId":16598,"journal":{"name":"Journal of Oral Microbiology","volume":"15 1","pages":"2225257"},"PeriodicalIF":4.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10281425/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10545149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}