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Frontiers in Oral Health 2024The study aimed to evaluate the impact of tobacco use on the composition and functions of the oral microbiome in healthy adult humans. (Review)
Review
OBJECTIVE
The study aimed to evaluate the impact of tobacco use on the composition and functions of the oral microbiome in healthy adult humans.
METHODS
We conducted a systematic search on PubMed, Web of Science, and Cinhal databases for literature published until 15 December 2023, to identify studies that have evaluated the oral microbiome with culture-independent next-generation techniques comparing the oral microbiome of tobacco users and non-users. The search followed the PECO format. The outcomes included changes in microbial diversity and abundance of microbial taxa. The quality assessment was performed using the Newcastle-Ottawa Scale (NOS) (PROSPERO ID CRD42022340151).
RESULTS
Out of 2,435 articles screened, 36 articles satisfied the eligibility criteria and were selected for full-text review. Despite differences in design, quality, and population characteristics, most studies reported an increase in bacterial diversity and richness in tobacco users. The most notable bacterial taxa enriched in users were and at the phylum level and , , and at the genus level. At the functional level, more similarities could be noted; and were increased in tobacco users compared to non-users. Most of the studies were of good quality on the NOS scale.
CONCLUSION
Tobacco smoking influences oral microbial community harmony, and it shows a definitive shift towards a proinflammatory milieu. Heterogeneities were detected due to sampling and other methodological differences, emphasizing the need for greater quality research using standardized methods and reporting.
SYSTEMATIC REVIEW REGISTRATION
CRD42022340151.
PubMed: 38445094
DOI: 10.3389/froh.2024.1310334 -
Heliyon Feb 2023The aim of this study was to summarize previously published data and assess the alterations in the composition of the oral microbiome in OSCC using a systematic review... (Review)
Review
OBJECTIVE
The aim of this study was to summarize previously published data and assess the alterations in the composition of the oral microbiome in OSCC using a systematic review and meta-analysis.
DESIGN
Electronic databases were systematically searched for studies on the oral microbiome in OSCC published before December 2021. Qualitative assessments of compositional variations at the phylum level were performed. The meta-analysis on abundance changes of bacteria genera was performed via a random-effects model.
RESULTS
A total of 18 studies involving 1056 participants were included. They consisted of two categories of studies: 1) case-control studies (n = 9); 2) nine studies that compared the oral microbiome between cancerous tissues and paired paracancerous tissues. At the phylum level, enrichment of Fusobacteria but depletion in Actinobacteria and Firmicutes in the oral microbiome was demonstrated in both categories of studies. At the genus level, showed an increased abundance in OSCC patients (SMD = 0.65, 95% CI: 0.43-0.87, Z = 5.809, = 0.000) and in cancerous tissues (SMD = 0.54, 95% CI: 0.36-0.72, Z = 5.785, = 0.000). The abundance of was decreased in OSCC (SMD = -0.46, 95% CI: -0.88-0.04, Z = -2.146, = 0.032) and in cancerous tissues (SMD = -0.45, 95% CI: -0.78-0.13, Z = -2.726, = 0.006).
CONCLUSIONS
Disturbances in the interactions between enriched and depleted may participate in or prompt the occurrence and development of OSCC and could be potential biomarkers for detection of OSCC.
PubMed: 36793959
DOI: 10.1016/j.heliyon.2023.e13198 -
International Journal of Environmental... Nov 2022The implementation of adjunctive antibiotics has been recommended for the therapy of peri-implantitis (PI). In this review, antibiotic resistance patterns in PI patients... (Review)
Review
The implementation of adjunctive antibiotics has been recommended for the therapy of peri-implantitis (PI). In this review, antibiotic resistance patterns in PI patients were assessed. A systematic scoping review of observational studies and trials was established in conjunction with the PRISMA extension for scoping reviews. The SCOPUS, PubMed/MEDLINE, EMBASE, SCIELO, Web of Science, and LILACS databases were reviewed along with the gray literature. The primary electronic examination produced 139 investigations. Finally, four observational studies met the selection criteria. These studies evaluated 214 implants in 168 patients. and mainly presented high resistance to tetracycline, metronidazole, and erythromycin in PI patients. Similarly, was also highly resistant to clindamycin and doxycycline. Other microorganisms such as , , and also presented significant levels of resistance to other antibiotics including amoxicillin, azithromycin, and moxifloxacin. However, most microorganisms did not show resistance to the combination amoxicillin metronidazole. Although the management of adjunctive antimicrobials in the therapy of PI is controversial, in this review, the resistance of relevant microorganisms to antibiotics used to treat PI, and usually prescribed in dentistry, was observed. Clinicians should consider the antibiotic resistance demonstrated in the treatment of PI patients and its public health consequences.
Topics: Humans; Peri-Implantitis; Aggregatibacter actinomycetemcomitans; Drug Resistance, Microbial; Fusobacterium nucleatum; Porphyromonas gingivalis; Amoxicillin; Metronidazole; Anti-Bacterial Agents
PubMed: 36497685
DOI: 10.3390/ijerph192315609 -
Current Nutrition Reports Sep 2022Cancers are a leading cause of death in humans and for many other species. Diet has often been associated with cancers, and the microbiome is an essential mediator... (Review)
Review
PURPOSE OF REVIEW
Cancers are a leading cause of death in humans and for many other species. Diet has often been associated with cancers, and the microbiome is an essential mediator between diet and cancers. Here, we review the work on cancer and the microbiome across species to search for broad patterns of susceptibility associated with different microbial species.
RECENT FINDINGS
Some microbes, such as Helicobacter bacteria, papillomaviruses, and the carnivore-associated Fusobacteria, consistently induce tumorigenesis in humans and other species. Other microbes, such as the milk-associated Lactobacillus, consistently inhibit tumorigenesis in humans and other species. We systematically reviewed over a thousand published articles and identified links between diet, microbes, and cancers in several species of mammals, birds, and flies. Future work should examine a larger variety of host species to discover new model organisms for human preclinical trials, to better understand the observed variance in cancer prevalence across species, and to discover which microbes and diets are associated with cancers across species. Ultimately, this could help identify microbial and dietary interventions to diagnose, prevent, and treat cancers in humans as well as other animals.
Topics: Animals; Carcinogenesis; Diet; Humans; Mammals; Microbiota; Neoplasms
PubMed: 35704266
DOI: 10.1007/s13668-022-00420-5 -
Frontiers in Cellular and Infection... 2022Recent data indicate the importance of gut-kidney axis in the pathogenesis of Immunoglobulin A nephropathy (IgAN). Growing evidence suggests the alterations of diversity... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Recent data indicate the importance of gut-kidney axis in the pathogenesis of Immunoglobulin A nephropathy (IgAN). Growing evidence suggests the alterations of diversity and composition of gut microbiome among patients with IgAN, however, the details are not yet fully understood.
METHODS
Eligible studies comparing the gut microbiome between patients with IgAN and non-IgAN individuals were systematically searched from PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, and . The primary outcomes were alpha- and beta-diversity, and the differences in gut microbiota composition between patients with IgAN and non-IgAN persons. Qualitative analysis and meta-analysis were performed according to available data.
RESULTS
Eleven cross-sectional studies, including 409 patients with IgAN and 243 healthy controls, were enrolled. No significant differences in the diversity and enrichment of gut bacteria were found between IgAN and healthy individuals, whereas the beta-diversity consistently showed significant microbial dissimilarities among the two groups. , and were the dominant phyla, however, no significant differences were found between IgAN patients and healthy controls at the phylum level. The genera, and showed a higher proportion in patients with IgAN compared to healthy individuals, whereas showed a lower abundance according to meta-analysis. Qualitative analyses suggested that might be increased in IgAN patients; the genera, ,and , members of and families, were likely to have decreased abundances in patients with IgAN compared to healthy individuals.
CONCLUSION
Gut microbiota dysbiosis was demonstrated in IgAN, which might be involved in the pathogenesis of IgAN. Further studies are needed to confirm the findings of this study, due to the substantial heterogeneity.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier PROSPERO (CRD42022304034).
Topics: Bacteroidetes; Clostridiales; Cross-Sectional Studies; Dysbiosis; Gastrointestinal Microbiome; Glomerulonephritis, IGA; Humans; Verrucomicrobia
PubMed: 35656030
DOI: 10.3389/fcimb.2022.904401 -
Frontiers in Oncology 2021Pelvic radiation therapy (RT) can impact the gut microbiome in patients with cancer and result in gastrointestinal (GI) toxicities. The purpose of this systematic review...
AIM
Pelvic radiation therapy (RT) can impact the gut microbiome in patients with cancer and result in gastrointestinal (GI) toxicities. The purpose of this systematic review was to describe the effects of RT on the gut microbiome and the associations between the gut microbiome and GI toxicities in patients treated with pelvic RT.
METHODS
PubMed, Embase, and Web of Science databases were searched from their earliest records to August 2020. The articles screening process adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The Mixed Method Assessment Tool was used to assess the methodological quality for each included study. All study findings were synthesized and presented in narrative format. Thirteen studies were included. The gut microbiome of fecal samples was analyzed using 16S rRNA sequencing approaches.
RESULTS
There were disparities in alpha and beta diversities that existed across the studies. Divergent results were found among various phyla, including , , and . Moreover, alteration in the gut microbiome diversity and abundance related to cancer treatment was associated with pelvic toxicities, specifically diarrhea. Following treatment, increases in the abundance of was associated with diarrhea and radiation enteritis.
CONCLUSIONS
Pelvic RT can disrupt the diversity and abundance of commensal gut microorganisms. A dysbiotic gut microbiome showed a promising association with radiation enteritis through alterations of the intestinal barrier function, innate immunity, and intestinal repair mechanisms; however, confounders, such as diet, were not thoroughly addressed.
PubMed: 34938654
DOI: 10.3389/fonc.2021.745262 -
Journal of Reproductive Immunology Feb 2022To assess the available scientific evidence regarding the placental microbial composition of a healthy pregnancy, the quality of this evidence, and the potential...
OBJECTIVE
To assess the available scientific evidence regarding the placental microbial composition of a healthy pregnancy, the quality of this evidence, and the potential relation between placental and oral microbiome.
MATERIALS AND METHODS
Data sources: MEDLINE and EMBASE up to August 1, 2019.
STUDY ELIGIBILITY CRITERIA
Human subjects; healthy women; term deliveries; healthy normal birth weight; assessment of microorganisms (bacteria) in placental tissue; full research papers in English. The quality of the included studies was assessed by a modified Joanna Briggs Institute checklist for analytical cross-sectional studies.
RESULTS
57 studies passed the inclusion criteria. Of these, 33 had a high risk of quality bias (e.g., insufficient infection control, lack of negative controls, poor description of the healthy cases). The remaining 24 studies had a low (N = 12) to moderate (N = 12) risk of bias and were selected for in-depth analysis. Of these 24 studies, 22 reported microorganisms in placental tissues, where Lactobacillus (11 studies), Ureaplasma (7), Fusobacterium (7), Staphylococcus (7), Prevotella (6) and Streptococcus (6) were among the most frequently identified genera. Methylobacterium (4), Propionibacterium (3), Pseudomonas (3) and Escherichia (2), among others, although frequently reported in placental samples, were often reported as contaminants in studies that used negative controls.
CONCLUSIONS
The results support the existence of a low biomass placental microbiota in healthy pregnancies. Some of the microbial taxa found in the placenta might have an oral origin. The high risk of quality bias for the majority of the included studies indicates that the results of individual papers should be interpreted with caution.
Topics: Adult; Animals; Female; Fusobacterium; Healthy Volunteers; Humans; Lactobacillus; Microbiota; Placenta; Pregnancy; RNA, Ribosomal, 16S; Ureaplasma
PubMed: 34883392
DOI: 10.1016/j.jri.2021.103455 -
Nutrients Aug 2021The human gut microbiota is defined as the microorganisms that collectively inhabit the intestinal tract. Its composition is relatively stable; however, an imbalance can...
BACKGROUND
The human gut microbiota is defined as the microorganisms that collectively inhabit the intestinal tract. Its composition is relatively stable; however, an imbalance can be precipitated by various factors and is known to be associated with various diseases. Humans are daily exposed to ionizing radiation from ambient and medical procedures, and gastrointestinal side effects are not rare.
METHODS
A systematic search of PubMed, EMBASE, and Cochrane Library databases was conducted. Primary outcomes were changes in composition, richness, and diversity of the gut microbiota after ionizing radiation exposure. Standard methodological procedures expected by Cochrane were used.
RESULTS
A total of 2929 nonduplicated records were identified, and based on the inclusion criteria, 11 studies were considered. Studies were heterogeneous, with differences in population and outcomes. Overall, we found evidence for an association between ionizing radiation exposure and dysbiosis: reduction in microbiota diversity and richness, increase in pathogenic bacteria abundance (Proteobacteria and Fusobacteria), and decrease in beneficial bacteria ( and .
CONCLUSIONS
This review highlights the importance of considering the influence of ionizing radiation exposure on gut microbiota, especially when considering the side effects of abdominal and pelvic radiotherapy. Better knowledge of these effects, with larger population studies, is needed.
Topics: Gastrointestinal Microbiome; Humans; Radiation Injuries; Radiation, Ionizing
PubMed: 34578902
DOI: 10.3390/nu13093025 -
International Journal of Environmental... Jul 2021The past decade has witnessed a surge in epidemiological studies that have explored the relationship between the oral microbiome and oral cancer. Owing to the diversity... (Review)
Review
The past decade has witnessed a surge in epidemiological studies that have explored the relationship between the oral microbiome and oral cancer. Owing to the diversity of the published data, a comprehensive systematic overview of the currently available evidence is critical. This review summarises the current evidence on the metagenomic studies on the oral microbiome in oral cancer. A systematic search was conducted in Medline and Embase databases to identify original studies examining the differences in the oral microbiome of oral cancer cases and controls. A total of twenty-six studies were identified that reported differences in microbial abundance between oral squamous cell carcinoma (OSCC) and controls. Although almost all the studies identified microbial dysbiosis to be associated with oral cancer, the detailed qualitative analysis did not reveal the presence/abundance of any individual bacteria or a consortium to be consistently enriched in OSCC samples across the studies. Interestingly, few studies reported a surge of periodontopathogenic taxa, especially , whereas others demonstrated a depletion of commensal taxa . Considerable heterogeneity could be identified in the parameters used for designing the studies as well as reporting the microbial data. If microbiome data needs to be translated in the future, to complement the clinical parameters for diagnosis and prognosis of oral cancer, further studies with the integration of clinical variables, adequate statistical power, reproducible methods, and models are required.
Topics: Carcinoma, Squamous Cell; Head and Neck Neoplasms; Humans; Metagenomics; Microbiota; Mouth Neoplasms; Squamous Cell Carcinoma of Head and Neck
PubMed: 34299675
DOI: 10.3390/ijerph18147224 -
Archives of Oral Biology Sep 2021To review published oral microbiome studies and create a comprehensive list of bacterial species found in saliva and dental plaque among healthy children and adults... (Review)
Review
OBJECTIVE
To review published oral microbiome studies and create a comprehensive list of bacterial species found in saliva and dental plaque among healthy children and adults associated with presence of carious lesions and caries-free state (oral health).
DESIGN
This review followed PRISMA-ScR guidelines. We searched published studies querying PUBMED and EMBASE using the following keywords: (plaque OR saliva) AND caries AND (next generation sequencing OR checkerboard OR 16s rRNA or qPCR). Studies were limited to human studies published in English between January 1, 2010 and June 24, 2020 that included > 10 caries-active and > 10 caries-free participants, and assessed the entire bacterial community.
RESULTS
Our search strategy identified 298 articles. After exclusion criteria, 22 articles remained; we considered 2 studies that examined saliva and plaque as separate studies, for a total of 24 studies. Species associated with caries or oral health varied widely among studies reviewed, with notable differences by age and biologic sample type. No bacterial species was associated with caries in all studies. Streptococcus mutans was found more frequently among those with caries (14/24 (58.3 %)) and Fusobacterium periodonticum was found more frequently among those that were caries-free (5/24 (20.8 %)).
CONCLUSION
No bacterial species was associated with caries or oral health across all studies supporting multiple pathways to cariogenesis. However, the variation may be due to sampling at different time points during caries development, varying methods of specimen sampling, storage, sequencing or analysis or differences in host factors such as age.
Topics: Adult; Child; Dental Caries; Fusobacterium; Humans; Mouth; Oral Health; RNA, Ribosomal, 16S; Saliva; Streptococcus mutans
PubMed: 34246103
DOI: 10.1016/j.archoralbio.2021.105204