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PloS One 2018We investigated the association between bacterial microbiota in breast milk and the infant mouth. The influence of human papilloma virus (HPV) infection on infant oral...
OBJECTIVE
We investigated the association between bacterial microbiota in breast milk and the infant mouth. The influence of human papilloma virus (HPV) infection on infant oral microbiota was also assessed.
MATERIAL AND METHODS
Altogether 35 breast milk and 35 infant oral samples with known HPV status were selected from the Finnish Family HPV Study cohort. In total, there were 31 mother-infant pairs. The microbiota composition was characterized by 16S rRNA gene sequencing (V3-V4 region).
RESULTS
HPV DNA was present in 8.6% (3/35) of the breast milk and 40% (14/35) of the infant oral samples. Eight shared genera between breast milk and infant oral were found; these included Streptococcus, Staphylococcus, Unclassified Gemellaceae, Rothia, Veillonella, Haemophilus, Propionibacterium and Corynebacterium. HPV status was not associated with either microbiota richness or diversity in the infant mouth. However, the infant oral microbiota clustered in different groups according to HPV status. We detected higher abundance of Veillonella dispar (p = 0.048) at species level in HPV negative infant oral samples. We did not detect differences in the breast milk microbiota composition related to HPV infection due to only three HPV positive milk samples.
CONCLUSIONS
HPV infection is associated with distinct oral bacterial microbiota composition in infants. The direction of causality underlying the phenomenon remains unclear.
Topics: Bacteria; Biodiversity; Cohort Studies; Discriminant Analysis; Female; Finland; Genotype; Humans; Infant; Infant, Newborn; Microbiota; Milk, Human; Mouth Mucosa; Papillomaviridae; Papillomavirus Infections; Principal Component Analysis; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Veillonella
PubMed: 30395655
DOI: 10.1371/journal.pone.0207016 -
Scientific Reports Sep 2018Human intestinal microbes can mediate development of arthritis - Studies indicate that certain bacterial nucleic acids may exist in synovial fluid (SF) and could be...
Human intestinal microbes can mediate development of arthritis - Studies indicate that certain bacterial nucleic acids may exist in synovial fluid (SF) and could be involved in arthritis, although the underlying mechanism remains unclear. To characterize potential SF bacterial nucleic acids, we used 16S rRNA gene amplicon sequencing to assess bacterial nucleic acid communities in 15 synovial tissue (ST) and 110 SF samples from 125 patients with rheumatoid arthritis (RA) and 16 ST and 42 SF samples from 58 patients with osteoarthritis (OA). Our results showed an abundant diversity of bacterial nucleic acids in these clinical samples, including presence of Porphyromonas and Bacteroides in all 183 samples. Agrobacterium, Comamonas, Kocuria, Meiothermus, and Rhodoplanes were more abundant in synovial tissues of rheumatoid arthritis (STRA). Atopobium, Phascolarctobacterium, Rhodotorula mucilaginosa, Bacteroides uniformis, Rothia, Megasphaera, Turicibacter, Leptotrichia, Haemophilus parainfluenzae, Bacteroides fragilis, Porphyromonas, and Streptococcus were more abundant in synovial tissues of osteoarthritis (STOA). Veillonella dispar, Haemophilus parainfluenzae, Prevotella copri and Treponema amylovorum were more abundant in synovial fluid of rheumatoid arthritis (SFRA), while Bacteroides caccae was more abundant in the synovial fluid of osteoarthritis (SFOA). Overall, this study confirms existence of bacterial nucleic acids in SF and ST samples of RA and OA lesions and reveals potential correlations with degree of disease.
Topics: Adult; Algorithms; Arthritis, Rheumatoid; Bacteria; Cytokines; Discriminant Analysis; Humans; Microbiota; Nucleic Acids; Osteoarthritis; Principal Component Analysis; Synovial Fluid; Synovial Membrane
PubMed: 30250232
DOI: 10.1038/s41598-018-32675-w -
Frontiers in Microbiology 2018The purpose of this study was to investigate strain dependent differences of the cariogenic biofilm forming within both simple and complex communities. A mono-species...
The purpose of this study was to investigate strain dependent differences of the cariogenic biofilm forming within both simple and complex communities. A mono-species containing representative clinical isolates (caries and non-caries), and a multispecies caries biofilm model containing , , and , and either of two representative clinical isolates (caries and non-caries), was developed as a comparison model. Compositional analysis of total and live bacteria within biofilms, and transcriptional analysis of biofilm associated virulence factors were evaluated by live/dead PCR and quantitative PCR, respectively. Scanning electron microscopy (SEM) was used to analyze the architecture of biofilm. One-way analysis of variance and -tests were used to investigate significant differences between independent groups of data. Within a mono-species biofilm, different strains responded similarly to one another during biofilm formation in different carbohydrate sources, with sucrose showing the highest levels of biofilm biomass and galactose showing the lowest. Within the polymicrobial biofilm system, compositional analysis of the bacteria within the biofilm showed that derived from a caries-free patient was preferentially composed of both total and viable , whereas derived from a caries patient was dominated by both total and viable ( < 0.001). Normalized gene expression analysis of , , , , , and , showed a general upregulation within the dominant biofilm. We were able to demonstrate that individual strains derived from different patients exhibited altered biofilm characteristics, which were not obvious within a simple mono-species biofilm model. Influencing the environmental conditions changed the composition and functionality within the polymicrobial biofilm. The biofilm model described herein provides a novel and reproducible method of assessing the impact on the biofilm microbiome upon different environmental influences.
PubMed: 30083138
DOI: 10.3389/fmicb.2018.01498 -
Frontiers in Microbiology 2018Colorectal cancer (CRC) is the third most diagnosed cancer worldwide due to its high difficulty in early diagnosis, high mortality rate and short life span. Recent...
Colorectal cancer (CRC) is the third most diagnosed cancer worldwide due to its high difficulty in early diagnosis, high mortality rate and short life span. Recent publications have demonstrated the involvement of the commensal gut microbiota in the initiation, progression and chemoresistance of CRC. However, this microbial community has not been explored within CRC patients after anti-cancer treatments. To this end, we performed next generation sequencing-based metagenomic analysis to determine the composition of the microbiota in CRC patients after anti-cancer treatments. The microbial 16S rRNA genes were analyzed from a total of 69 fecal samples from four clinical groups, including healthy individuals, CRC patients, and CRC patients treated with surgery or chemotherapy. The findings suggested that surgery greatly reduced the bacterial diversity of the microbiota in CRC patients. Moreover, were shown to confer chemoresistance during CRC therapy, and certain bacterial strains or genera, such as the genus and species , were specifically associated with CRC patients who were treated with chemotherapeutic cocktails, suggesting their potential relationships with chemoresistance. These candidate bacterial genera or strains may have the ability to enhance the dosage response to conventional chemotherapeutic cocktails or reduce the side effects of these cocktails. A combination of common CRC risk factors, such as age, gender and BMI, identified in this study improved our understanding of the microbial community and its compositional variation during anti-cancer treatments. However, the underlying mechanisms of these microbial candidates remain to be investigated in animal models. Taken together, the findings of this study indicate that fecal microbiome-based approaches may provide additional methods for monitoring and optimizing anti-cancer treatments.
PubMed: 30065719
DOI: 10.3389/fmicb.2018.01607 -
NPJ Biofilms and Microbiomes 2018is a Gram-negative organism, strongly associated with aggressive forms of periodontitis. An important virulence property of is its ability to form tenacious biofilms...
is a Gram-negative organism, strongly associated with aggressive forms of periodontitis. An important virulence property of is its ability to form tenacious biofilms that can attach to abiotic as well as biotic surfaces. The histone-like (H-NS) family of nucleoid-structuring proteins act as transcriptional silencers in many Gram-negative bacteria. To evaluate the role of H-NS in , mutant derivatives of serotype a strain D7S were generated. Characteristics of the mutant phenotype included shorter and fewer pili, and substantially lower monospecies biofilm formation relative to the wild type. Furthermore, the D7S mutant exhibited significantly reduced growth within a seven-species oral biofilm model. However, no apparent difference was observed regarding the numbers and proportions of the remaining six species regardless of being co-cultivated with D7S or its parental strain. Proteomics analysis of the strains grown in monocultures confirmed the role of H-NS as a repressor of gene expression in . Interestingly, proteomics analysis of the multispecies biofilms indicated that the wild type and mutant imposed different regulatory effects on the pattern of protein expression in the other species, i.e., mainly spp., , and . Gene ontology analysis revealed that a large portion of the differentially regulated proteins was related to translational activity. Taken together, our data suggest that, apart from being a negative regulator of protein expression in , H-NS promotes biofilm formation and may be an important factor for survival of this species within a multispecies biofilm.
PubMed: 29844920
DOI: 10.1038/s41522-018-0055-4 -
PloS One 2018Peri-implant infections are the most common cause of implant failure in modern dental implantology. These are caused by the formation of biofilms on the implant surface...
Peri-implant infections are the most common cause of implant failure in modern dental implantology. These are caused by the formation of biofilms on the implant surface and consist of oral commensal and pathogenic bacteria, which harm adjacent soft and hard tissues and may ultimately lead to implant loss. In order to improve the clinical situation, there has to be a better understanding of biofilm formation on abiotic surfaces. Therefore, we successfully developed a system to cultivate an oral multispecies biofilm model in a flow chamber system, optimized for the evaluation of biofilm formation on solid materials by direct microscopic investigation. The model contains four relevant oral bacterial species: Streptococcus oralis, Actinomyces naeslundii, Veillonella dispar and Porphyromonas gingivalis in ratios similar to the native situation. The reliability of the developed "Hanoverian Oral Multispecies Biofilm Implant Flow Chamber" (HOBIC) model was verified. Biofilm volume and live/dead distribution within biofilms were determined by fluorescence staining and confocal laser scanning microcopy (CLSM). The individual species distribution was analyzed using quantitative real time PCR with propidium monoazide pretreatment (PMA-qRT-PCR) and by urea-NaCl fluorescence in situ hybridization (urea-NaCl-FISH). This in vitro model may be used to analyze biofilm formation on dental implants in more detail and to develop future implant systems with improved material properties.
Topics: Bacteria; Bacterial Physiological Phenomena; Biofilms; Humans; Models, Biological; Mouth Mucosa
PubMed: 29771975
DOI: 10.1371/journal.pone.0196967 -
Free Radical Biology & Medicine May 2018Nitric oxide (NO) can be generated endogenously via NO synthases or via the diet following the action of symbiotic nitrate-reducing bacteria in the oral cavity. Given...
Nitric oxide (NO) can be generated endogenously via NO synthases or via the diet following the action of symbiotic nitrate-reducing bacteria in the oral cavity. Given the important role of NO in smooth muscle control there is an intriguing suggestion that cardiovascular homeostasis may be intertwined with the presence of these bacteria. Here, we measured the abundance of nitrate-reducing bacteria in the oral cavity of 25 healthy humans using 16S rRNA sequencing and observed, for 3.5 h, the physiological responses to dietary nitrate ingestion via measurement of blood pressure, and salivary and plasma NO metabolites. We identified 7 species of bacteria previously known to contribute to nitrate-reduction, the most prevalent of which were Prevotella melaninogenica and Veillonella dispar. Following dietary nitrate supplementation, blood pressure was reduced and salivary and plasma nitrate and nitrite increased substantially. We found that the abundance of nitrate-reducing bacteria was associated with the generation of salivary nitrite but not with any other measured variable. To examine the impact of bacterial abundance on pharmacokinetics we also categorised our participants into two groups; those with a higher abundance of nitrate reducing bacteria (> 50%), and those with a lower abundance (< 50%). Salivary nitrite production was lower in participants with lower abundance of bacteria and these individuals also exhibited slower salivary nitrite pharmacokinetics. We therefore show that the rate of nitrate to nitrite reduction in the oral cavity is associated with the abundance of nitrate-reducing bacteria. Nevertheless, higher abundance of these bacteria did not result in an exaggerated plasma nitrite response, the best known marker of NO bioavailability. These data from healthy young adults suggest that the abundance of oral nitrate-reducing bacteria does not influence the generation of NO through the diet, at least when the host has a functional minimum threshold of these microorganisms.
Topics: Adult; Bacteria; Cross-Sectional Studies; Female; Humans; Male; Microbiota; Mouth; Nitrates; Nitric Oxide; Nitrites; Saliva
PubMed: 29550328
DOI: 10.1016/j.freeradbiomed.2018.03.023 -
Archives of Oral Biology May 2018Fluoride is widely used as an anti-caries agent, e.g. in toothpastes and mouth rinses. However, the nature of the anti-caries action is not entirely clear. Mechanisms...
OBJECTIVE
Fluoride is widely used as an anti-caries agent, e.g. in toothpastes and mouth rinses. However, the nature of the anti-caries action is not entirely clear. Mechanisms suspected to explain the cariostatic effect include inhibitory effects on acid formation by bacteria, inhibition of extracellular polysaccharide (EPS) production, inhibition of enamel demineralization and enhancement of remineralizaton or combination thereof. The aim of this study was to examine with the supragingival Zurich in vitro biofilm model the effect of fluoride in NaF formulation, on the microbiota and on demineralization.
METHODS
Biofilms consisting of Actinomyces oris, Candida albicans, Fusobacterium nucleatum, Streptococcus oralis, Veillonella dispar and Streptococcus sobrinus, were grown anaerobically on sintered hydroxyapatite or bovine enamel disks, exposed to 200, 400, and 1400 ppm of NaF, or 0.1% chlorhexidine (positive control). The biofilms were harvested after 64 h and CFUs were assessed for total bacteria. Demineralization of enamel disks was measured by quantitative light-induced fluorescence.
RESULTS
NaF did not affect the bacterial numbers. No enamel mineral loss was observed at 1400 and 400 ppm of fluoride, whereas the pH of the surrounding medium was increased to 5.5 and 5.0, respectively, compared to the untreated control (pH 4.5 and mineral loss ΔF of -32%). At 1400 ppm NaF the biofilm's EPS volume was also significantly reduced.
CONCLUSIONS
Administration of NaF completely prevented demineralization without affecting biofilm composition and growth. This protective effect may be attributed to the observed decrease in acid production or EPS volume, or to a shift in the de/remineralization balance.
Topics: Animals; Anti-Infective Agents; Bacteria; Biofilms; Cariostatic Agents; Cattle; Chlorhexidine; Dental Caries; Dental Enamel; Dose-Response Relationship, Drug; Durapatite; Fluorides; Hydrogen-Ion Concentration; In Vitro Techniques; Microbiota; Mouth; Mouthwashes; Phosphates; Saliva; Sodium Fluoride; Tooth Calcification; Tooth Demineralization; Toothpastes
PubMed: 29482049
DOI: 10.1016/j.archoralbio.2018.02.010 -
Journal of Medical Microbiology Mar 2018Micro-organisms are important triggers of peri-implant inflammation and analysing their diversity is necessary for peri-implantitis treatment. This study aimed to...
PURPOSE
Micro-organisms are important triggers of peri-implant inflammation and analysing their diversity is necessary for peri-implantitis treatment. This study aimed to analyse and compare the microbiota associated with individuals with peri-implantitis, as well as clinically healthy implant sites.
METHODOLOGY
Subgingival biofilm samples were taken from 10 individuals with peri-implantitis and from at least 1 clinically healthy implant. DNA was extracted and bacterial 16S rRNA genes were amplified using universal primers. After cloning the PCR-products, amplified inserts of positive clones were digested using restriction endonucleases, and the chosen clones were sequenced. The 16S rDNA-sequences were compared to those from the public sequence databases GenBank, EMBL and DDBJ to determine the corresponding taxa.
RESULTS
Differing distributions of taxa belonging to the phyla Firmicutes, Bacteroidetes, Fusobacteria, Actinobacteria, Proteobacteria, Synergistetes, Spirochaetae and TM 7 were detected in both the healthy implant (HI) and the peri-implantitis (PI) groups. A significantly higher relative abundance of phylum Bacteroidetes, as well as of the species Fusobacterium nucleatum, were found in the PI group (P<0.05). The putative periodontal red complex (Porphyromonas gingivalis, Tannerella forsythia) was also detected at significantly higher levels in the PI group (P<0.05), whereas the yellow group, as well as the species Veillonella dispar, tended to be associated with the HI group.
CONCLUSION
A shift in the healthy subgingival microbiota was shown in peri-implantitis-associated biofilm. Anaerobic Gram-negative periopathogens, including P. gingivalis and T. forsythia, seem to play an important role in peri-implantitis development and should be considered in treatment and prevention strategies.
Topics: Aged; Aged, 80 and over; Bacteria; Bacterial Load; Bacterial Physiological Phenomena; Bacteroides; Biofilms; Female; Fusobacterium nucleatum; Genes, rRNA; Gingiva; Humans; Male; Microbiota; Middle Aged; Peri-Implantitis; Porphyromonas gingivalis; Prevotella intermedia; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 29458668
DOI: 10.1099/jmm.0.000682 -
Molecular Oral Microbiology Jun 2018Bacteria residing in oral biofilms live in a state of dynamic equilibrium with one another. The intricate synergistic or antagonistic interactions between them are...
Bacteria residing in oral biofilms live in a state of dynamic equilibrium with one another. The intricate synergistic or antagonistic interactions between them are crucial for determining this balance. Using the six-species Zürich "supragingival" biofilm model, this study aimed to investigate interactions regarding growth and localization of the constituent species. As control, an inoculum containing all six strains was used, whereas in each of the further five inocula one of the bacterial species was alternately absent, and in the last, both streptococci were absent. Biofilms were grown anaerobically on hydroxyapatite disks, and after 64 h they were harvested and quantified by culture analyses. For visualization, fluorescence in situ hybridization and confocal laser scanning microscopy were used. Compared with the control, no statistically significant difference of total colony-forming units was observed in the absence of any of the biofilm species, except for Fusobacterium nucleatum, whose absence caused a significant decrease in total bacterial numbers. Absence of Streptococcus oralis resulted in a significant decrease in Actinomyces oris, and increase in Streptococcus mutans (P < .001). Absence of A. oris, Veillonella dispar or S. mutans did not cause any changes. The structure of the biofilm with regards to the localization of the species did not result in observable changes. In summary, the most striking observation of the present study was that absence of S. oralis resulted in limited growth of commensal A. oris and overgrowth of S. mutans. These data establish highlight S. oralis as commensal keeper of homeostasis in the biofilm by antagonizing S. mutans, so preventing a caries-favoring dysbiotic state.
Topics: Actinomyces; Biofilms; Colony Count, Microbial; Durapatite; Fusobacterium nucleatum; Homeostasis; In Situ Hybridization, Fluorescence; Microbial Consortia; Microbial Interactions; Microscopy, Confocal; Streptococcus mutans; Streptococcus oralis; Veillonella
PubMed: 29327482
DOI: 10.1111/omi.12216