AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: Cumulative dental pla...AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: Cumulative dental plaque specimens and gastric biopsies were submitted to histological exami-nation, rapid urease test and polymerase chain reac-tion (PCR) assays to detect the presence of cagA and vacA polymorphisms.RESULTS: Detection of H. pylori from dental plaque and gastric biopsy samples was greater by PCR com-pared to histological examination and the rapid ure-ase test. DNA from H. pylori was detected in 96% of gastric mucosa samples and in 72% of dental plaque samples. Sixty-three (89%) of 71 dental plaque sam-ples that were H. pylori-positive also exhibited identical vacA and cagA genotypes in gastric mucosa. The most common genotype was vacAs1bm1 and cagA positive, either in dental plaque or gastric mucosa. These viru-lent H. pylori isolates were involved in the severity of clinical outcome.CONCLUSION: These pathogenic strains were found simultaneously in dental plaque and gastric mucosa, which suggests that gastric infection is correlated with the presence of H. pylori in the mouth.展开更多
Helicobacter pylori (H. pylori) infection is one of the most common bacterial infections in humans. Although H. pylori may be detected in the stomach of approximately half of the world’s population, the me...Helicobacter pylori (H. pylori) infection is one of the most common bacterial infections in humans. Although H. pylori may be detected in the stomach of approximately half of the world’s population, the mechanisms of transmission of the microorganism from individual to individual are not yet clear. Transmission of H. pylori could occur through iatrogenic, fecal-oral, and oral-oral routes, and through food and water. The microorganism may be transmitted orally and has been detected in dental plaque and saliva. However, the role of the oral cavity in the transmission and recurrence of H. pylori infection has been the subject of debate. A large number of studies investigating the role of oral hygiene and periodontal disease in H. pylori infection have varied significantly in terms of their methodology and sample population, resulting in a wide variation in the reported results. Nevertheless, recent studies have not only shown that the microorganism can be detected fairly consistently from the oral cavity but also demonstrated that the chances of recurrence of H. pylori infection is more likely among patients who harbor the organism in the oral cavity. Furthermore, initial results from clinical trials have shown that H. pylori-positive dyspeptic patients may benefit from periodontal therapy. This paper attempts to review the current body of evidence regarding the role of dental plaque, saliva, and periodontal disease in H. pylori infection.展开更多
AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cr...AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens,CONCLUSION:Regard to high similarity in genotype of H.pylori isolates from saliva,stomach and stool,this study support the idea which fecal-oral is the main route of H.pylori transmission and oral cavity may serve as a reservoir for H.pylori,however,remarkable genotype diversity among stomach,saliva and stool samples showed that more than one H.pylori genotype may exist in a same patient.展开更多
<span style="font-family:""><span style="font-family:Verdana;">Oral bacteria (e.g. </span><i><span style="font-family:Verdana;">Porphyromonas gingivalis...<span style="font-family:""><span style="font-family:Verdana;">Oral bacteria (e.g. </span><i><span style="font-family:Verdana;">Porphyromonas gingivalis</span></i><span style="font-family:Verdana;">) are associated and potentially co-causative in several medical conditions including Alzheimer’s disease and increased cardiovascular risk. Naturally occurring polyphenols are a developing class of antimicrobial pharmaceutical agents. The use of plant-based</span><span style="color:red;"> </span><span style="font-family:Verdana;">polyphenol compounds is an attractive area of medical and dental research due to their high safety factor from their presence in vegetables and fruits. This preliminary study evaluated polyphenols found in berries to reduce bacterial dental plaque accumulation. The study was an </span><i><span style="font-family:Verdana;">in vivo</span></i><span style="font-family:Verdana;"> single blind randomized controlled trial of seven subjects with a novel tooth gel using validated measurements. Results showed a significant reduction in plaque accumulation (p</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.005) and a non-significant trend to reduce gingivitis (p</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.08). The bioactive gel showed no local or systemic adverse effects and was well tolerated by subjects.展开更多
Phototherapy with blue light emitting diodes (LEDs) is gaining interest because of the efficient antimicrobial benefits reported in several studies in the last decade. The aim in this study was to investigate if a too...Phototherapy with blue light emitting diodes (LEDs) is gaining interest because of the efficient antimicrobial benefits reported in several studies in the last decade. The aim in this study was to investigate if a toothbrush with incorporated blue light used in daily oral care can reduce dental plaque and gingival inflammation. An 8-week single-blinded randomized controlled clinical study including 48 subjects compared effects of toothbrushes with/without 450 nm blue LED light emission, on clinical parameters (plaque index, gingival index, bleeding on probing), and on inflammatory markers in saliva and gingival crevicular fluid. Significant reductions in dental plaque and gingival inflammation (p < 0.001), and in some inflammatory markers (p ≤ 0.05), matrix metalloproteinase (MMP)-8, tissue inhibitor metalloproteinase inhibitor (TIMP)-1, interleukin (IL)-1β and interleukin (IL)-8, were detected within both groups from baseline to follow-up. For all subjects dental plaque was reduced with 57%, and a reduction in gingival inflammation was demonstrated by a decrease in gingival index (GI) with 46% and in bleeding on probing (BOP) with a decrease of 15%. No significant differences were found between the groups at a level of p = 0.05. However, the amount of plaque was reduced by 62% in the blue light group and 51% in the control group, a difference established at a level of p = 0.058. A toothbrush with a 450 nm LED did not show any statistical significant adjunctive effect of toothbrushing regarding reduction in measurements of dental plaque and gingival inflammation.展开更多
Purpose: In implant treatment, the abutments and superstructures form a transmucosal area. In addition to providing appropriate cleaning instructions to patients, its material properties must be carefully considered. ...Purpose: In implant treatment, the abutments and superstructures form a transmucosal area. In addition to providing appropriate cleaning instructions to patients, its material properties must be carefully considered. It is not clear how much plaque adhesion occurs at each site during treatment process, and the effect of materials on plaque adhesion. Methods: In this study, 33 patients, 13 maxillary cases and 20 mandibular cases, who had implants placed in the missing molars were evaluated for the plaque adhesion of provisional restorations made of acrylic resin and monolithic zirconia final restoration after a period of more than 4 weeks. In addition, oral hygiene instructions were thoroughly given for 12 cases at the time of staining after the provisional restorations, and re-evaluated in 4 weeks. Results: About 20% of the buccal-lingual area of the prosthetic device fabricated with acrylic resin showed plaque staining, whereas about 40% of the area of the mesial and distal. On the other hand, for the zirconia final restorations, the percentage of staining was about 5% for buccal and lingual surface and 10% for mesial and distal surface. The stained area ratio of the provisional restoration correlated with the zirconia superstructure area ratio. Even with careful oral hygiene, it became clear that the amount of plaque adhesion due to the difference in materials could not be overcome. Conclusion: The zirconia superstructure is extremely good from the viewpoint of plaque adhesion, but cases with a large stained area at the time of provisional restoration should be carefully followed up.展开更多
The objective of this study was to investigate the compositional profiles and microbial shifts of oral microbiota during head-and-neck radiotherapy.Bioinformatic analysis based on 16S rRNA gene pyrosequencing was perf...The objective of this study was to investigate the compositional profiles and microbial shifts of oral microbiota during head-and-neck radiotherapy.Bioinformatic analysis based on 16S rRNA gene pyrosequencing was performed to assess the diversity and variation of oral microbiota of irradiated patients.Eight patients with head and neck cancers were involved in this study.For each patient, supragingival plaque samples were collected at seven time points before and during radiotherapy.A total of 147 232 qualified sequences were obtained through pyrosequencing and bioinformatic analysis,representing 3 460 species level operational taxonomic units(OTUs) and 140 genus level taxa.Temporal variations were observed across different time points and supported by cluster analysis based on weighted UniFrac metrics.Moreover,the low evenness of oral microbial communities in relative abundance was revealed by Lorenz curves.This study contributed to a better understanding of the detailed characterization of oral bacterial diversity of irradiated patients.展开更多
Lactobacilli have been consistently associated with dental caries for decades;however, knowledge of this group of bacteria in the etiology of the disease is limited to quantitative elucidation. Nowadays, explicit iden...Lactobacilli have been consistently associated with dental caries for decades;however, knowledge of this group of bacteria in the etiology of the disease is limited to quantitative elucidation. Nowadays, explicit identification of oral Lactobacillus species is possible, despite their taxonomic complexity. Here we describe a combined approach involving both cultivation and genetic methods to ascertain and characterize the diversity and abundance of the Lactobacillus population in the oral cavities of children with severe early childhood caries (S-ECC). Eighty 3- to 6-year-old children (40 S-ECC and 40 caries free) who were seeking dental care at the Pediatric Dental Clinic of Bellevue Hospital in New York City were invited to participate in this study. Clinical data on sociodemographic information and oral health behavior were obtained from the primary caregiver. The data included a detailed dental examination, children’s medical history, and a questionnaire survey. Combined non-stimulated saliva and supragingival plaque samples were collected from each child and cultivated on selective media for quantitative measures of lactobacilli levels. The procedure for Lactobacillus species screening will include the random selection of 50 colonies per plate, ex- traction of DNA from each colony, and genotyping by arbitrarily primed polymerase chain reaction (AP-PCR). Each unique Lactobacillus AP-PCR genotype will be selected for taxonomic assessment by 16S rRNA gene sequencing analysis. Lactobacillus species will be identified by comparing the 16S rRNA sequences with the Ribosomal Database and the Human Oral Microbiome Database. Meanwhile, the same set of clinical samples will be independently subjected to genomic DNA isolation, 16S rRNA amplification with Lactobacillus genus-specific primers, sequencing, and taxonomic identification, both at genus and species levels with a customized pipeline. The distribution and phylogenetic differences of these Lactobacillus species will be compared between children with or without S-ECC. One of the main objectives of this study is to establish a study protocol for the identification and characterization of lactobacilli in the oral cavity. Future caries risk assessments can include lactobacilli counts (quantitative) and the presence/absence of specific cario- genic genetic signatures of a Lactobacillus species (qualitative) associated with S-ECC.展开更多
The oral microbiota plays an important role in the development of various diseases,whereas its association with gestational diabetes mellitus (GDM) remains largely unclear.The aim of this study is to identify biomarke...The oral microbiota plays an important role in the development of various diseases,whereas its association with gestational diabetes mellitus (GDM) remains largely unclear.The aim of this study is to identify biomarkers from the oral microbiota of GDM patients by analyzing the microbiome of the saliva and dental plaque samples of 111 pregnant women.We find that the microbiota of both types of oral samples in GDM patients exhibits differences and significantly varies from that of patients with periodontitis or dental caries.Using bacterial biomarkers from the oral microbiota,GDM classification models based on support vector machine and random forest algorithms are constructed.The area under curve (AUC) value of the classification model constructed by combination of Lautropia and Neisseria in dental plaque and Streptococcus in saliva reaches 0.83,and the value achieves a maximum value of 0.89 by adding clinical features.These findings suggest that certain bacteria in either saliva or dental plaque can effectively distinguish women with GDM from healthy pregnant women,which provides evidence of oral microbiome as an informative source for developing noninvasive biomarkers of GDM.展开更多
基金Supported by Coordenao de Aperfeioamento de Pessoal de Nível Superior and Federal University of Pará
文摘AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: Cumulative dental plaque specimens and gastric biopsies were submitted to histological exami-nation, rapid urease test and polymerase chain reac-tion (PCR) assays to detect the presence of cagA and vacA polymorphisms.RESULTS: Detection of H. pylori from dental plaque and gastric biopsy samples was greater by PCR com-pared to histological examination and the rapid ure-ase test. DNA from H. pylori was detected in 96% of gastric mucosa samples and in 72% of dental plaque samples. Sixty-three (89%) of 71 dental plaque sam-ples that were H. pylori-positive also exhibited identical vacA and cagA genotypes in gastric mucosa. The most common genotype was vacAs1bm1 and cagA positive, either in dental plaque or gastric mucosa. These viru-lent H. pylori isolates were involved in the severity of clinical outcome.CONCLUSION: These pathogenic strains were found simultaneously in dental plaque and gastric mucosa, which suggests that gastric infection is correlated with the presence of H. pylori in the mouth.
文摘Helicobacter pylori (H. pylori) infection is one of the most common bacterial infections in humans. Although H. pylori may be detected in the stomach of approximately half of the world’s population, the mechanisms of transmission of the microorganism from individual to individual are not yet clear. Transmission of H. pylori could occur through iatrogenic, fecal-oral, and oral-oral routes, and through food and water. The microorganism may be transmitted orally and has been detected in dental plaque and saliva. However, the role of the oral cavity in the transmission and recurrence of H. pylori infection has been the subject of debate. A large number of studies investigating the role of oral hygiene and periodontal disease in H. pylori infection have varied significantly in terms of their methodology and sample population, resulting in a wide variation in the reported results. Nevertheless, recent studies have not only shown that the microorganism can be detected fairly consistently from the oral cavity but also demonstrated that the chances of recurrence of H. pylori infection is more likely among patients who harbor the organism in the oral cavity. Furthermore, initial results from clinical trials have shown that H. pylori-positive dyspeptic patients may benefit from periodontal therapy. This paper attempts to review the current body of evidence regarding the role of dental plaque, saliva, and periodontal disease in H. pylori infection.
基金Supported by The Islamic Azad University,Shahre Kord Branch-Iran grant 89/8761
文摘AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens,CONCLUSION:Regard to high similarity in genotype of H.pylori isolates from saliva,stomach and stool,this study support the idea which fecal-oral is the main route of H.pylori transmission and oral cavity may serve as a reservoir for H.pylori,however,remarkable genotype diversity among stomach,saliva and stool samples showed that more than one H.pylori genotype may exist in a same patient.
文摘<span style="font-family:""><span style="font-family:Verdana;">Oral bacteria (e.g. </span><i><span style="font-family:Verdana;">Porphyromonas gingivalis</span></i><span style="font-family:Verdana;">) are associated and potentially co-causative in several medical conditions including Alzheimer’s disease and increased cardiovascular risk. Naturally occurring polyphenols are a developing class of antimicrobial pharmaceutical agents. The use of plant-based</span><span style="color:red;"> </span><span style="font-family:Verdana;">polyphenol compounds is an attractive area of medical and dental research due to their high safety factor from their presence in vegetables and fruits. This preliminary study evaluated polyphenols found in berries to reduce bacterial dental plaque accumulation. The study was an </span><i><span style="font-family:Verdana;">in vivo</span></i><span style="font-family:Verdana;"> single blind randomized controlled trial of seven subjects with a novel tooth gel using validated measurements. Results showed a significant reduction in plaque accumulation (p</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.005) and a non-significant trend to reduce gingivitis (p</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.08). The bioactive gel showed no local or systemic adverse effects and was well tolerated by subjects.
基金The Swedish Research Council,Contract No K2014-70X-22533-01-3,Praktikertjanst AB,Karolinska Institutet,Huddinge,Sweden and Stockholm University,Stockholm,Sweden supported the study
文摘Phototherapy with blue light emitting diodes (LEDs) is gaining interest because of the efficient antimicrobial benefits reported in several studies in the last decade. The aim in this study was to investigate if a toothbrush with incorporated blue light used in daily oral care can reduce dental plaque and gingival inflammation. An 8-week single-blinded randomized controlled clinical study including 48 subjects compared effects of toothbrushes with/without 450 nm blue LED light emission, on clinical parameters (plaque index, gingival index, bleeding on probing), and on inflammatory markers in saliva and gingival crevicular fluid. Significant reductions in dental plaque and gingival inflammation (p < 0.001), and in some inflammatory markers (p ≤ 0.05), matrix metalloproteinase (MMP)-8, tissue inhibitor metalloproteinase inhibitor (TIMP)-1, interleukin (IL)-1β and interleukin (IL)-8, were detected within both groups from baseline to follow-up. For all subjects dental plaque was reduced with 57%, and a reduction in gingival inflammation was demonstrated by a decrease in gingival index (GI) with 46% and in bleeding on probing (BOP) with a decrease of 15%. No significant differences were found between the groups at a level of p = 0.05. However, the amount of plaque was reduced by 62% in the blue light group and 51% in the control group, a difference established at a level of p = 0.058. A toothbrush with a 450 nm LED did not show any statistical significant adjunctive effect of toothbrushing regarding reduction in measurements of dental plaque and gingival inflammation.
文摘Purpose: In implant treatment, the abutments and superstructures form a transmucosal area. In addition to providing appropriate cleaning instructions to patients, its material properties must be carefully considered. It is not clear how much plaque adhesion occurs at each site during treatment process, and the effect of materials on plaque adhesion. Methods: In this study, 33 patients, 13 maxillary cases and 20 mandibular cases, who had implants placed in the missing molars were evaluated for the plaque adhesion of provisional restorations made of acrylic resin and monolithic zirconia final restoration after a period of more than 4 weeks. In addition, oral hygiene instructions were thoroughly given for 12 cases at the time of staining after the provisional restorations, and re-evaluated in 4 weeks. Results: About 20% of the buccal-lingual area of the prosthetic device fabricated with acrylic resin showed plaque staining, whereas about 40% of the area of the mesial and distal. On the other hand, for the zirconia final restorations, the percentage of staining was about 5% for buccal and lingual surface and 10% for mesial and distal surface. The stained area ratio of the provisional restoration correlated with the zirconia superstructure area ratio. Even with careful oral hygiene, it became clear that the amount of plaque adhesion due to the difference in materials could not be overcome. Conclusion: The zirconia superstructure is extremely good from the viewpoint of plaque adhesion, but cases with a large stained area at the time of provisional restoration should be carefully followed up.
基金supported by a grant from the National Natural Science Foundation(No.81070826/30872886) of Chinapartly sponsored by Shanghai Rising-Star Program(No.12QH1401400)funded by the Shanghai Jiao Tong University(Grant No.YG2011MS67)
文摘The objective of this study was to investigate the compositional profiles and microbial shifts of oral microbiota during head-and-neck radiotherapy.Bioinformatic analysis based on 16S rRNA gene pyrosequencing was performed to assess the diversity and variation of oral microbiota of irradiated patients.Eight patients with head and neck cancers were involved in this study.For each patient, supragingival plaque samples were collected at seven time points before and during radiotherapy.A total of 147 232 qualified sequences were obtained through pyrosequencing and bioinformatic analysis,representing 3 460 species level operational taxonomic units(OTUs) and 140 genus level taxa.Temporal variations were observed across different time points and supported by cluster analysis based on weighted UniFrac metrics.Moreover,the low evenness of oral microbial communities in relative abundance was revealed by Lorenz curves.This study contributed to a better understanding of the detailed characterization of oral bacterial diversity of irradiated patients.
基金supported by the National Institute of Dental and Craniofacial Research(R01DE019455).
文摘Lactobacilli have been consistently associated with dental caries for decades;however, knowledge of this group of bacteria in the etiology of the disease is limited to quantitative elucidation. Nowadays, explicit identification of oral Lactobacillus species is possible, despite their taxonomic complexity. Here we describe a combined approach involving both cultivation and genetic methods to ascertain and characterize the diversity and abundance of the Lactobacillus population in the oral cavities of children with severe early childhood caries (S-ECC). Eighty 3- to 6-year-old children (40 S-ECC and 40 caries free) who were seeking dental care at the Pediatric Dental Clinic of Bellevue Hospital in New York City were invited to participate in this study. Clinical data on sociodemographic information and oral health behavior were obtained from the primary caregiver. The data included a detailed dental examination, children’s medical history, and a questionnaire survey. Combined non-stimulated saliva and supragingival plaque samples were collected from each child and cultivated on selective media for quantitative measures of lactobacilli levels. The procedure for Lactobacillus species screening will include the random selection of 50 colonies per plate, ex- traction of DNA from each colony, and genotyping by arbitrarily primed polymerase chain reaction (AP-PCR). Each unique Lactobacillus AP-PCR genotype will be selected for taxonomic assessment by 16S rRNA gene sequencing analysis. Lactobacillus species will be identified by comparing the 16S rRNA sequences with the Ribosomal Database and the Human Oral Microbiome Database. Meanwhile, the same set of clinical samples will be independently subjected to genomic DNA isolation, 16S rRNA amplification with Lactobacillus genus-specific primers, sequencing, and taxonomic identification, both at genus and species levels with a customized pipeline. The distribution and phylogenetic differences of these Lactobacillus species will be compared between children with or without S-ECC. One of the main objectives of this study is to establish a study protocol for the identification and characterization of lactobacilli in the oral cavity. Future caries risk assessments can include lactobacilli counts (quantitative) and the presence/absence of specific cario- genic genetic signatures of a Lactobacillus species (qualitative) associated with S-ECC.
基金supported by the National Natural Science Foundation of China (31722031, 31670119, 31870107 and 32070122)the Key Research Program of the Chinese Academy of Sciences (KFZDSW-219)the Medical Health Science and Technology Project of Zhejiang Provincial (2019ZD048, 2018275012)。
文摘The oral microbiota plays an important role in the development of various diseases,whereas its association with gestational diabetes mellitus (GDM) remains largely unclear.The aim of this study is to identify biomarkers from the oral microbiota of GDM patients by analyzing the microbiome of the saliva and dental plaque samples of 111 pregnant women.We find that the microbiota of both types of oral samples in GDM patients exhibits differences and significantly varies from that of patients with periodontitis or dental caries.Using bacterial biomarkers from the oral microbiota,GDM classification models based on support vector machine and random forest algorithms are constructed.The area under curve (AUC) value of the classification model constructed by combination of Lautropia and Neisseria in dental plaque and Streptococcus in saliva reaches 0.83,and the value achieves a maximum value of 0.89 by adding clinical features.These findings suggest that certain bacteria in either saliva or dental plaque can effectively distinguish women with GDM from healthy pregnant women,which provides evidence of oral microbiome as an informative source for developing noninvasive biomarkers of GDM.
