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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 -
Frontiers in Microbiology 2023Despite the growing body of evidence, the link between the gut microbiota and different types of tumors, such as colorectal, gastric, and liver cancer, is becoming more...
INTRODUCTION
Despite the growing body of evidence, the link between the gut microbiota and different types of tumors, such as colorectal, gastric, and liver cancer, is becoming more apparent. The gut microbiota can be used as a reference for evaluating various diseases, including cancer, and can also act as risk factors or preventive factors. However, the specific connection between the gut microbiota and the advancement of esophageal cancer has yet to be investigated. Therefore, the aim of this research is to clarify the possible causal influence of intestinal microorganisms on the vulnerability to esophageal cancer through the utilization of Mendelian randomization (MR) studies.
METHODS
In this study, we employed a two-sample Mendelian randomization approach to evaluate the unbiased causal association between 150 different gut microbiota types and the occurrence of esophageal cancer. Following the selection from the IEU GWAS database and SNP filtration, we utilized various MR statistical techniques on the suitable instrumental variables. These included IVW methods, employing inverse variance weighting. Additionally, we performed a range of sensitivity analyses to confirm the heterogeneity and pleiotropy of the instrumental variables, thus ensuring the reliability of the outcomes.
RESULTS
The increased likelihood of developing esophageal cancer is linked to the genetically predicted high levels of , and . Conversely, a decreased risk of esophageal cancer is associated with the high abundance of , and . No heterogeneity and pleiotropy were detected in the sensitivity analysis.
DISCUSSION
We found that 11 types of gut microbial communities are associated with esophageal cancer, thereby confirming that the gut microbiota plays a significant role in the path.
PubMed: 38107856
DOI: 10.3389/fmicb.2023.1286598 -
Frontiers in Cellular and Infection... 2024The incidence of biliary system diseases has been continuously increasing in the past decade. Biliary system diseases bring a heavy burden to humanity and society....
INTRODUCTION
The incidence of biliary system diseases has been continuously increasing in the past decade. Biliary system diseases bring a heavy burden to humanity and society. However, the specific etiology and pathogenesis are still unknown. The biliary system, as a bridge between the liver and intestine, plays an indispensable role in maintaining the physiological metabolism of the body. Therefore, prevention and treatment of biliary diseases are crucial. It is worth noting that the microorganisms participate in the lipid metabolism of the bile duct, especially the largest proportion of intestinal bacteria.
METHODS
We systematically reviewed the intestinal microbiota in patients with gallstones (GS), non-calculous biliary inflammatory, and biliary tract cancer (BTC). And searched Pubmed, Embase and Web of science for research studies published up to November 2023.
RESULTS
We found that the abundance of Faecalibacterium genus is decreased in GS, primary sclerosing cholangitis (PSC), primary biliary cholangitis (PBC) and BTC. Veillonella, Lactobacillus, Streptococcus and Enterococcus genus were significantly increased in PSC, PBC and BTC. Interestingly, we found that the relative abundance of Clostridium was generally reduced in GS, PBC and BTC. However, Clostridium was generally increased in PSC.
DISCUSSION
The existing research mostly focuses on exploring the mechanisms of bacteria targeting a single disease. Lacking comparison of multiple diseases and changes in bacteria during the disease process. We hope to provide biomarkers forearly diagnosis of biliary system diseases and provide new directions for the mechanism of intestinal microbiota in biliary diseases.
Topics: Humans; Gastrointestinal Microbiome; Cholangitis, Sclerosing; Biliary Tract; Liver; Biomarkers; Bacteria
PubMed: 38558851
DOI: 10.3389/fcimb.2024.1362933 -
JDR Clinical and Translational Research Jul 2021To compare the oral microbiota of Sjögren's syndrome (SS) with that of healthy subjects (HS).
OBJECTIVE
To compare the oral microbiota of Sjögren's syndrome (SS) with that of healthy subjects (HS).
METHODS
Supragingival and subgingival biofilm samples were collected from the mesial-buccal tooth surfaces of SS patients (n = 57) and age- and sex-matched HS (n = 53). Unstimulated saliva and 8 oral tissue samples were taken using a buccal brush. Caries and periodontal measures were recorded. All supragingival samples and a subgroup of 24 SS and 28 HS subgingival samples, as well as 32 SS and 11 HS saliva and oral tissue samples, were analyzed for their content of 41 bacterial species using checkerboard DNA-DNA hybridization. Mean levels (×10 ± SEM) and percentage of DNA probe counts of each species were determined for each sample site and averaged within subjects in the 2 clinical groups. Kruskal-Wallis tests, adjusting for multiple comparisons and cluster analysis, were used for soft tissue and microbial analysis, and the Mann-Whitney test was used to compare caries and periodontal measures.
RESULTS
Mean (×10 ± SEM) total DNA probe counts in supragingival samples were significantly lower (P < 0.001) in the SS (13.3 ± .7) compared to the HS (44.1 ± 6.8) group. In supragingival samples, Veillonella parvula, Fusobacterium nucleatum ss vincenti, and Propionibacterium acnes were markedly elevated in the SS compared to the HS group in both mean (×10 ± SEM) and mean (± SEM) percentage DNA probe counts (P < 0.001). In subgingival samples of SS, V. parvula was significantly different compared to HS (P < 0.05). SS was characterized by high levels of purple and low levels of orange and red complexes. Cluster analysis of oral tissues and saliva demonstrated that the mean microbial profiles for SS patients and the HS group clustered separately. Active root caries (P < 0.003) and attachment loss were significantly higher (P < 0.029) in the SS group compared to the HS group.
CONCLUSION
These findings indicate that saliva is a major controlling factor of intraoral biofilm. V. parvula may be a unique microbial biomarker for Sjögren's syndrome.
KNOWLEDGE TRANSFER STATEMENT
The microbiome characterized for Sjögren's syndrome in salivary hypofunction is shown to be under stress and reduced. Veillonella parvula can be a possible identification of a biomarker for Sjögren's syndrome.
Topics: Colony Count, Microbial; DNA, Bacterial; Dental Plaque; Humans; Microbiota; Sjogren's Syndrome; Veillonella
PubMed: 32689841
DOI: 10.1177/2380084420940623 -
Frontiers in Cellular and Infection... 2023The present study aims to investigate the effect of (Hp) infection on gastric mucosal microbiota in patients with chronic gastritis.
OBJECTIVE
The present study aims to investigate the effect of (Hp) infection on gastric mucosal microbiota in patients with chronic gastritis.
METHODS
Here recruited a population of 193 patients with both chronic gastritis and positive rapid urease, including 124 patients with chronic atrophic gastritis (CAG) and 69 patients with chronic non-atrophic gastritis (nCAG). Immunoblotting was used to detect four serum Hp antibodies (UreA, UreB, VacA and CagA) to determine the types of virulent Hp-I and avirulent Hp-II infections. Gastric microbiota was profiled by 16S rRNA gene V3-V4 region, and R software was used to present the relationship between the microbial characteristics and the type of Hp infection.
RESULTS
In the stomach of patients with Hp-positive gastritis, the dominant gastric bacterial genera included (23.94%), (20.28%), (9.99%), (9.21%), (5.05%), and (4.75%). The proportion of Hp-I infection was significantly higher in CAG patients (91.1%) than in nCAG patients (71.0%) ( < 0.001). The gastric microbiota richness index (observed OTUs, Chao) was significantly lower in CAG patients than in nCAG patients (0.05). Compared with avirulent Hp-II infection, virulent Hp-I infection significantly decreased the Shannon index in CAG patients (0.05). In nCAG patients, Hp-I infected patients had lower abundances of several dominant gastric bacteria (, , , , ) than Hp-II infected patients. Meanwhile, in CAG patients, Hp-I infected patients occupied lower abundances of several dominant oral bacteria (, and ) than Hp-II infected patients. In addition, bile reflux significantly promoted the colonization of dominant oral microbiota (, and ) in the stomach of CAG patients. There was no significant symbiotic relationship between bacteria and non- bacteria in the stomach of nCAG patients, while bacteria distinctly linked with the non- bacteria (, , , and ) in CAG patients.
CONCLUSIONS
Virulent Hp infection alters the gastric microbiota, reduces microbial diversity, and enhances the symbiotic relationship between the bacteria and non- bacteria in patients with chronic gastritis. The data provides new evidence for treating Hp infection by improving the gastric microbiota.
Topics: Humans; Helicobacter pylori; Helicobacter Infections; RNA, Ribosomal, 16S; Gastritis
PubMed: 37662018
DOI: 10.3389/fcimb.2023.1221433 -
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