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Frontiers in Medicine 2023The etiology of preterm birth (PTB) is heterogeneous and not yet well known. Maternal periodontal disease has been investigated for decades and is a known risk factor...
BACKGROUND
The etiology of preterm birth (PTB) is heterogeneous and not yet well known. Maternal periodontal disease has been investigated for decades and is a known risk factor for adverse pregnancy outcomes. However, no particular bacterial species or higher taxonomic order has been found as causative of PTB, leading to studies of the whole oral microbiome. In order to determine if and how the composition of the oral microbiome is associated with PTB, we performed a large case-control study including women with term (TB) and PTB.
METHODS
We compared oral microbiomes in PTB to TB, to examine differences in the microbial richness, diversity, and differential abundance of specific taxa. We obtained oral swab samples from 152 Caucasian pregnant women who were classified as either PTB (≤36 6/7 weeks, = 61) or TB (≥38 0/7 weeks, = 91) in exclusion of any other major medical or obstetric conditions. The oral microbiomes of these women were characterized by 16S ribosomal RNA (rRNA) gene sequencing of the V3-V4 region on the MiSeq platform.
RESULTS
The dominant microorganisms at the phylum level in all pregnant women regardless of birth week outcomes as belonging to , and . The phyla and were relatively more abundant in women with a PTB than in women with a TB, while was less prevalent in women with a PTB. At the genus level, , , and were enriched in the PTB, and while many of the members of these genera could not be resolved to the species level, was shown to be increased in the PTB group.
CONCLUSION
We identified the genera , , and in the maternal oral microbiome as being associated with PTB independently of clinically apparent infection, uterine anomalies, and other pregnancy complications, including placenta previa, and placental abruption. The clarification of the role of those taxa in the etiology of PTB merits further research.
PubMed: 37608830
DOI: 10.3389/fmed.2023.1177990 -
Gut Mar 2020The significance of the liver-microbiome axis has been increasingly recognised as a major modulator of autoimmunity. The aim of this study was to take advantage of a...
OBJECTIVE
The significance of the liver-microbiome axis has been increasingly recognised as a major modulator of autoimmunity. The aim of this study was to take advantage of a large well-defined corticosteroids treatment-naïve group of patients with autoimmune hepatitis (AIH) to rigorously characterise gut dysbiosis compared with healthy controls.
DESIGN
We performed a cross-sectional study of individuals with AIH (n=91) and matched healthy controls (n=98) by 16S rRNA gene sequencing. An independent cohort of 28 patients and 34 controls was analysed to validate the results. All the patients were collected before corticosteroids therapy.
RESULTS
The gut microbiome of steroid treatment-naïve AIH was characterised with lower alpha-diversity (Shannon and observed operational taxonomic units, both p<0.01) and distinct overall microbial composition compared with healthy controls (p=0.002). Depletion of obligate anaerobes and expansion of potential pathobionts including were associated with disease status. Of note, , the most strongly disease-associated taxa (p=8.85E-8), positively correlated with serum level of aspartate aminotransferase and liver inflammation. Furthermore, the combination of four patients with AIH-associated genera distinguished AIH from controls with an area under curves of approximately 0.8 in both exploration and validation cohorts. In addition, multiple predicted functional modules were altered in the AIH gut microbiome, including lipopolysaccharide biosynthesis as well as metabolism of amino acids that can be processed by bacteria to produce immunomodulatory metabolites.
CONCLUSION
Our study establishes compositional and functional alterations of gut microbiome in AIH and suggests the potential for using gut microbiota as non-invasive biomarkers to assess disease activity.
Topics: Adolescent; Adult; Aged; Aspartate Aminotransferases; Case-Control Studies; Clostridiales; Cross-Sectional Studies; Dysbiosis; Female; Gastrointestinal Microbiome; Hepatitis, Autoimmune; Humans; Lactobacillus; Male; Middle Aged; Severity of Illness Index; Veillonella; Young Adult
PubMed: 31201284
DOI: 10.1136/gutjnl-2018-317836 -
Cancer Metastasis Reviews Jun 2022The identification of microbes enriched in the healthy lung has led to the compelling discovery that microbes may contribute to lung cancer pathogenesis. Here, we review... (Review)
Review
The identification of microbes enriched in the healthy lung has led to the compelling discovery that microbes may contribute to lung cancer pathogenesis. Here, we review the recent literature showing microbial associations with lung cancer as well as the functional features that have been identified in human and murine studies. Most biomarker data remain limited due to variable findings. However, multiple studies have found that lung tumors or ipsilateral airway samples have decreased α diversity compared to normal tissue. Specific genera, such as Veillonella and Streptococcus, were also found in association with lung tumors using multiple sampling methodologies. These microbes, which are generally found in the upper respiratory track, are associated with an IL-17 signature in the lung, potentially resulting in a pro-tumorigenic environment. Studies detailing these immune mechanisms are limited, and further investigation is necessary to delineate how these bacteria, their metabolites, and potentially tumor-associated neoantigens modulate the immune response in cancer.
Topics: Animals; Bacteria; Biomarkers; Humans; Immunity; Lung Neoplasms; Mice; Microbiota
PubMed: 35588337
DOI: 10.1007/s10555-022-10036-4 -
Scientific Reports Jul 2023Primary liver cancer (PLC), which includes intrahepatic cholangiocarcinoma (iCCA) and hepatocellular carcinoma (HCC), has the highest incidence of all cancer types in...
Primary liver cancer (PLC), which includes intrahepatic cholangiocarcinoma (iCCA) and hepatocellular carcinoma (HCC), has the highest incidence of all cancer types in Thailand. Known etiological factors, such as viral hepatitis and chronic liver disease do not fully account for the country's unusually high incidence. However, the gut-liver axis, which contributes to carcinogenesis and disease progression, is influenced by the gut microbiome. To investigate this relationship, fecal matter from 44 Thai PLC patients and 76 healthy controls were subjected to whole-genome metagenomic shotgun sequencing and then analyzed by marker gene-based and assembly based methods. Results revealed greater gut microbiome heterogeneity in iCCA compared to HCC and healthy controls. Two Veillonella species were found to be more abundant in iCCA samples and could distinguish iCCA from HCC and healthy controls. Conversely, Ruminococcus gnavus was depleted in iCCA patients and could distinguish HCC from iCCA samples. High Veillonella genus counts in the iCCA group were associated with enriched amino acid biosynthesis and glycolysis pathways, while enriched phospholipid and thiamine metabolism pathways characterized the HCC group with high Blautia genus counts. These findings reveal distinct landscapes of gut dysbiosis among Thai iCCA and HCC patients and warrant further investigation as potential biomarkers.
Topics: Humans; Carcinoma, Hepatocellular; Liver Neoplasms; Dysbiosis; Southeast Asian People; Thailand; Bile Duct Neoplasms; Cholangiocarcinoma; Bile Ducts, Intrahepatic
PubMed: 37452065
DOI: 10.1038/s41598-023-38307-2 -
Microbiology Spectrum Feb 2023species are abundant members of the human oral microbiome with multiple interspecies commensal relationships. Examining the distribution patterns of species across the...
species are abundant members of the human oral microbiome with multiple interspecies commensal relationships. Examining the distribution patterns of species across the oral cavity is fundamental to understanding their oral ecology. In this study, we used a combination of pangenomic analysis and oral metagenomic information to clarify taxonomy and to test the site specialist hypothesis for the genus, which contends that most oral bacterial species are adapted to live at specific oral sites. Using isolate genome sequences combined with shotgun metagenomic sequence data, we showed that species have clear, differential site specificity: Veillonella parvula showed strong preference for supra- and subgingival plaque, while closely related V. dispar, as well as more distantly related V. atypica, preferred the tongue dorsum, tonsils, throat, and hard palate. In addition, the provisionally named sp. Human Microbial Taxon 780 showed strong site specificity for keratinized gingiva. Using comparative genomic analysis, we identified genes associated with thiamine biosynthesis and the reductive pentose phosphate cycle that may enable species to occupy their respective habitats. Understanding the microbial ecology of the mouth is fundamental for understanding human physiology. In this study, metapangenomics demonstrated that different species have clear ecological preferences in the oral cavity of healthy humans, validating the site specialist hypothesis. Furthermore, the gene pool of different species was found to be reflective of their ecology, illuminating the potential role of vitamins and carbohydrates in determining distribution patterns and interspecies interactions.
Topics: Humans; Veillonella; Mouth; Tongue; Palatine Tonsil; Microbiota
PubMed: 36695592
DOI: 10.1128/spectrum.04042-22 -
Frontiers in Oral Health 2021The genus comprises 16 characterized species, among which eight are commonly found in the human oral cavity. The high abundance of species in the microbiome of both... (Review)
Review
The genus comprises 16 characterized species, among which eight are commonly found in the human oral cavity. The high abundance of species in the microbiome of both supra- and sub-gingival biofilms, and their interdependent relationship with a multitude of other bacterial species, suggest veillonellae to play an important role in oral biofilm ecology. Development of oral biofilms relies on an incremental coaggregation process between early, bridging and later bacterial colonizers, ultimately forming multispecies communities. As early colonizer and bridging species, veillonellae are critical in guiding the development of multispecies communities in the human oral microenvironment. Their ability to establish mutualistic relationships with other members of the oral microbiome has emerged as a crucial factor that may contribute to health equilibrium. Here, we review the general characteristics, taxonomy, physiology, genomic and genetics of veillonellae, as well as their bridging role in the development of oral biofilms. We further discuss the role of spp. as potential "accessory pathogens" in the human oral cavity, capable of supporting colonization by other, more pathogenic species. The relationship between spp. and dental caries, periodontitis, and peri-implantitis is also recapitulated in this review. We finally highlight areas of future research required to better understand the intergeneric signaling employed by veillonellae during their bridging activities and interspecies mutualism. With the recent discoveries of large species and strain-specific variation within the genus in biological and virulence characteristics, the study of as an example of highly adaptive microorganisms that indirectly participates in dysbiosis holds great promise for broadening our understanding of polymicrobial disease pathogenesis.
PubMed: 35048073
DOI: 10.3389/froh.2021.774115 -
Current Opinion in Microbiology Feb 2024The respiratory tract microbiome (RTM) is a microbial ecosystem inhabiting different niches throughout the airway. A critical role for the RTM in dictating lung... (Review)
Review
The respiratory tract microbiome (RTM) is a microbial ecosystem inhabiting different niches throughout the airway. A critical role for the RTM in dictating lung infection outcomes is underlined by recent efforts to identify community members benefiting respiratory tract health. Obligate anaerobes common in the oropharynx and lung such as Prevotella and Veillonella are associated with improved pneumonia outcomes and activate several immune defense pathways in the lower airway. Colonizers of the nasal cavity, including Corynebacterium and Dolosigranulum, directly impact the growth and virulence of lung pathogens, aligning with robust clinical correlations between their upper airway abundance and reduced respiratory tract infection risk. Here, we highlight recent work identifying respiratory tract bacteria that promote airway health and resilience against disease, with a focus on lung infections and the underlying mechanisms driving RTM-protective benefits.
Topics: Humans; Lung; Oropharynx; Respiratory Tract Infections; Pneumonia, Bacterial; Microbiota
PubMed: 38277901
DOI: 10.1016/j.mib.2024.102428 -
World Journal of Gastroenterology Dec 2020Microbiota profiles differ between patients with pancreatic cancer and healthy people, and understanding these differences may help in early detection of pancreatic...
BACKGROUND
Microbiota profiles differ between patients with pancreatic cancer and healthy people, and understanding these differences may help in early detection of pancreatic cancer. Saliva sampling is an easy and cost-effective way to determine microbiota profiles compared to fecal and tissue sample collection.
AIM
To investigate the saliva microbiome distribution in patients with pancreatic adenocarcinoma (PDAC) and the role of oral microbiota profiles in detection and risk prediction of pancreatic cancer.
METHODS
We conducted a prospective study of patients with pancreatic cancer ( = 41) and healthy individuals ( = 69). Bacterial taxa were identified by 16S ribosomal ribonucleic acid gene sequencing, and a linear discriminant analysis effect size algorithm was used to identify differences in taxa. Operational taxonomic unit values of all selected taxa were converted into a normalized Z-score, and logistic regressions were used to calculate risk prediction of pancreatic cancer.
RESULTS
Compared with the healthy control group, carriage of and (z-score) was associated with a higher risk of PDAC [odds ratio (OR) = 5.344, 95% confidence interval (CI): 1.282-22.282, = 0.021 and OR = 6.886, 95%CI: 1.423-33.337, = 0.016, respectively]. and (z-score) were considered a protective microbe that decreased the risk of PDAC (OR = 0.187, 95%CI: 0.055-0.631, = 0.007 and OR = 0.309, 95%CI: 0.100-0.952, = 0.041, respectively). Among the patients with PDAC, patients reporting bloating have a higher abundance of ( = 0.039), ( = 0.024), and ( = 0.041); while patients reporting jaundice had a higher amount of ( = 0.008); patients reporting dark brown urine had a higher amount of ( = 0.035). Patients reporting diarrhea had a lower amount of and ( = 0.024 and = 0.034), and patients reporting vomiting had decreased ( = 0.036).
CONCLUSION
Saliva microbiome was able to distinguish patients with pancreatic cancer and healthy individuals. may be specific for patients living in Sichuan Province, southwest China. Symptomatic patients had different bacteria profiles than asymptomatic patients. Combined symptom and microbiome evaluation may help in the early detection of pancreatic cancer.
Topics: Adenocarcinoma; China; Humans; Microbiota; Pancreatic Neoplasms; Prospective Studies; RNA, Ribosomal, 16S; Saliva
PubMed: 33505144
DOI: 10.3748/wjg.v26.i48.7679 -
Cureus Sep 2023A lung abscess is characterized as a clinical ailment arising from the localized suppurative necrosis of lung parenchyma. This condition primarily results from the...
A lung abscess is characterized as a clinical ailment arising from the localized suppurative necrosis of lung parenchyma. This condition primarily results from the complications of aspiration pneumonia due to anaerobic microorganisms originating from the oral cavity. Clinically, patients typically manifest symptoms such as fever, malaise, and a productive cough persisting over several weeks. The majority of lung abscess cases acquired within the community stem from anaerobic bacterial infections, often exhibiting a polymicrobial nature. We present a 51-year-old female with intrapulmonary abscess and empyema, with isolation of species. She has a 25-pack-year smoking history. Two weeks prior to arrival at our facility, she experienced intermittent shortness of breath, fever, and subjective fever. Her primary care physician ordered an outpatient computed tomography (CT) which showed evidence of a large right-sided fluid collection. Initial chest X-ray at our facility revealed extensive opacification of the middle and right lower hemithorax, believed to be a large-sized pleural effusion with adjacent pneumonia or atelectasis. She was given a working diagnosis of right-sided empyema. Cardiothoracic surgery was consulted and video-assisted thoracoscopic surgery (VATS) was performed. A very large collection of grossly purulent material was evacuated and revealed a large intrapulmonary abscess. Over 400 cc of frank pus was collected and sent for microbiological analysis. Anaerobic culture demonstrated 3+ species and 3+ species. The genus consists of a small, strictly anaerobic, gram-negative cocci that lacks flagella, spores, and capsules. This genus obtains energy from the utilization of short-chain organic acids that are present in the oral cavity and intestinal tract. Oral is strongly associated with biofilms, causing human oral infectious diseases such as periodontitis and dental caries. Literature states that this organism has been isolated in a limited number of chronic pneumonitis cases. To date, the most common organism isolated from lung abscesses is in adult patients and in pediatric patients. We strive to elucidate the distinctive clinical presentation evident in this case, alongside a comprehensive understanding of the unusual pathogens identified in the disease's pathogenesis.
PubMed: 37842426
DOI: 10.7759/cureus.45210 -
Anaerobe Dec 2022Veillonella, known as early colonizers in oral biofilms, take part in some infections in human. Biofilm refers to complex, sessile communities of microbes, which...
INTRODUCTION
Veillonella, known as early colonizers in oral biofilms, take part in some infections in human. Biofilm refers to complex, sessile communities of microbes, which function as strong barriers for bacteria to survive. Biofilm matrixes surrounding bacteria enable them to withstand harsh conditions, protect against immune cells, etc., and also make them resistant to antimicrobial treatments. Thus, the knowledge of antibiotic susceptibility and biofilm formation of Veillonella will shed light on their resistance mechanism.
MATERIALS AND METHOD
Their morphology was observed by scanning electron microscopy (SEM). According to the performance standards for antibiotic susceptibility testing of the Clinical & Laboratory Standards Institute, the Agar dilution method was used to study the susceptibility of Veillonella strains to eight antibiotics (ampicillin, piperacillin-tazobactam, cefoxitin, tetracycline, moxifloxacin, clindamycin, metronidazole, and vancomycin). In addition, we applied the crystal violet staining method to reveal the processes of biofilm formation of these Veillonella strains.
RESULTS
V. rogosae, V. nakazawae, and V. parvula were isolated from oral cavities of healthy adults and V. ratti was isolated from dairy goat droppings. Observations by scanning electron microscopy showed that Veillonella were spherical and arranged in single or short chains. The diameter of a single cell was about 0.3-0.5 μm. The Minimum Inhibitory Concentrations (MICs) of the antibiotics were determined and the results showed that these four strains were all sensitive to cefoxitin, tetracycline, moxifloxacin, clindamycin and metronidazole. Among the four strains, V. ratti was resistant to piperacillin-tazobactam, and V. rogosae and V. nakazawae were resistant to ampicillin. The vancomycin susceptibility of the four Veillonella strains varied greatly. The MICs of vancomycin against V. rogosae and V. ratti were greater than 256 μg/mL but the MICs of vancomycin against V. nakazawae and V. parvula were less than 2 μg/mL. V. parvula had significantly higher biofilm-forming ability than the other three strains (p < 0.05) and V. nakazawae had the weakest biofilm-forming ability.
CONCLUSION
In this study, V. rogosae, V. nakazawae, V. parvula and V. ratti were isolated and identified. The four strains of Veillonella showed differences in MIC values for different antibiotics and biofilm-forming ability.
Topics: Humans; Veillonella; Vancomycin; Cefoxitin; Clindamycin; Moxifloxacin; Metronidazole; Biofilms; Microbial Sensitivity Tests; Anti-Bacterial Agents; Ampicillin; Tetracyclines; Piperacillin; Tazobactam
PubMed: 36288773
DOI: 10.1016/j.anaerobe.2022.102667