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Frontiers in Cellular and Infection... 2023Previous research has posited a potential correlation between the gut microbiota and the onset of appendicitis; however, the precise causal connection between...
BACKGROUND
Previous research has posited a potential correlation between the gut microbiota and the onset of appendicitis; however, the precise causal connection between appendicitis and the gut microbiota remains an unresolved and contentious issue.
METHODS
In this investigation, we performed a Mendelian randomization (MR) analysis employing publicly accessible summary data extracted from genome-wide association studies (GWAS) to elucidate the potential causal nexus between the gut microbiota and the development of appendicitis. We initially identified instrumental variables (IVs) through a comprehensive array of screening methodologies, subsequently executing MR analyses using the Inverse Variance Weighted (IVW) technique as our primary approach, supplemented by several alternative methods such as MR Egger, weighted median, simple mode, and weighted mode. Additionally, we implemented a series of sensitivity analysis procedures, encompassing Cochran's Q test, MR-Egger intercept test, Mendelian Randomized Polymorphism Residual and Outlier (MR-PRESSO) test, and a leave-one-out test, to affirm the robustness and validity of our findings.
RESULTS
Our investigation indicates that an elevated prevalence of Deltaproteobacteria, Christensenellaceae, Desulfovibrionaceae, Eubacterium ruminantium group, Lachnospiraceae NK4A136 group, Methanobrevibacter, Desulfovibrionales, and Euryarchaeota is inversely associated with the risk of appendicitis. Conversely, we observed a positive correlation between an increased abundance of Family XIII, Howardella, and Veillonella and the susceptibility to appendicitis. Sensitivity analyses have corroborated the robustness of these findings, and Mendelian randomization analyses provided no indications of reverse causality.
CONCLUSION
Our Mendelian randomization (MR) analysis has unveiled potential advantageous or detrimental causal associations between the gut microbiota and the occurrence of appendicitis. This study offers novel theoretical and empirical insights into the understanding of appendicitis pathogenesis, along with its implications for preventive and therapeutic strategies.
Topics: Humans; Gastrointestinal Microbiome; Appendicitis; Genome-Wide Association Study; Mendelian Randomization Analysis; Causality; Clostridiales
PubMed: 38162578
DOI: 10.3389/fcimb.2023.1320992 -
Clinical and Experimental Dental... Dec 2022Diet is one of the main factors influencing the diversity and interactions of the oral microbiota. The purpose of this study is to determine the impact of sugar intake... (Review)
Review
OBJECTIVES
Diet is one of the main factors influencing the diversity and interactions of the oral microbiota. The purpose of this study is to determine the impact of sugar intake on the microbial diversity and bacteria that predominate under these conditions.
MATERIAL AND METHODS
A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guide, using the PubMed, Scopus, and Science Direct databases and combinations of the words "microbiota," "microbiology," "bacteria," "sugars," "dysbiosis," "caries," "microbiome," "oral microbial," and "oral microbiota profile pattern." The selection criteria included year, language, type of publication, comparison of microbiota during low and high sugar intake, and bacterial identification by molecular sequencing of the 16S subunit of ribosomal RNA.
RESULTS
Out of a total of 374 papers that came up after the initial search, 8 met the criteria for this review. The papers included research on populations comprising children, young adults, and adults, with most of the studies reporting selection criteria for the participants and using validated instruments to determine sugar intake. Apart from one study, all others reported for high sugar intake conditions a significant decrease in microbial diversity of the oral microbiome and the predominance of several bacterial genera or species, including Streptococcus, Scardovia, Veillonella, Rothia, Actinomyces, and Lactobacillus.
CONCLUSIONS
Sugar-rich diets have a significantly unfavorable effect on the diversity and balance of oral microbiota; however, further studies are required to determine the exact role of sugar in microbial interactions.
Topics: Child; Young Adult; Humans; Microbiota; Bacteria; Dental Caries; Dysbiosis; Sugars
PubMed: 35946056
DOI: 10.1002/cre2.640 -
ERJ Open Research Jul 2020The aim of this study was to investigate whether the compositionality of the lower airway microbiota predicts later exacerbation risk in persons with COPD in a cohort...
AIM
The aim of this study was to investigate whether the compositionality of the lower airway microbiota predicts later exacerbation risk in persons with COPD in a cohort study.
MATERIALS AND METHODS
We collected lower airways microbiota samples by bronchoalveolar lavage and protected specimen brushes, and oral wash samples from 122 participants with COPD. Bacterial DNA was extracted from all samples, before we sequenced the V3-V4 region of the 16S RNA gene. The frequency of moderate and severe COPD exacerbations was surveyed in telephone interviews and in a follow-up visit. Compositional taxonomy and α and β diversity were compared between participants with and without later exacerbations.
RESULTS
The four most abundant phyla were Firmicutes, Bacteroidetes, Proteobacteria and Fusobacteria in both groups, and the four most abundant genera were , , and . The relative abundances of different taxa showed a large variation between samples and individuals, and no statistically significant difference of either compositional taxonomy, or α or β diversity could be found between participants with and without COPD exacerbations within follow-up.
CONCLUSION
The findings from the current study indicate that individual differences in the lower airway microbiota in persons with COPD far outweigh group differences between frequent and nonfrequent COPD exacerbators, and that the compositionality of the microbiota is so complex as to present large challenges for use as a biomarker of later exacerbations.
PubMed: 32904583
DOI: 10.1183/23120541.00168-2020 -
IDCases 2019A 79-year-old woman with a history of total hysterectomy for cervical cancer with ureterocutaneostomy presented with high fever. She had tenderness and a hard lump...
A 79-year-old woman with a history of total hysterectomy for cervical cancer with ureterocutaneostomy presented with high fever. She had tenderness and a hard lump around the ureterocutaneostomy site. Computed tomography scan revealed 1.5 cm ureteral calculus in ureterocutaneous fistula (Fig. 1A) associated with bilateral hydronephrosis (Fig. 1B) and we performed a transureteral stent insertion. Blood culture grew methicillin-sensitive (MSSA), , species and and urine culture revealed , MSSA, and . The patient's clinical signs and symptoms gradually improved with ampicillin/sulbactam. Patients with urinary diversions including ureterocutaneostomy and iliac conduits are at increased risk of urolithiasis (1), which can cause sepsis, pyelonephritis, and renal insufficiency (2). Since most patients become colonized with a multitude of bacteria including and skin flora such as and spp., we should empirically treat with broad-spectrum antimicrobials until the culture results are available. Early diagnosis and urological intervention are required because it can be life-threatening with delayed treatment.
PubMed: 31720220
DOI: 10.1016/j.idcr.2019.e00624 -
Cancer Reports (Hoboken, N.J.) Nov 2023Gut microbiota dictates the fate of several diseases, including cancer. Most gastric cancers (GC) belong to gastric adenocarcinomas (GAC). Helicobacter pylori colonizes... (Review)
Review
Gut microbiota dictates the fate of several diseases, including cancer. Most gastric cancers (GC) belong to gastric adenocarcinomas (GAC). Helicobacter pylori colonizes the gastric epithelium and is the causative agent of 75% of all stomach malignancies globally. This bacterium has several virulence factors, including cytotoxin-associated gene A (CagA), vacuolating cytotoxin (VacA), and outer membrane proteins (OMPs), all of which have been linked to the development of gastric cancer. In addition, bacteria such as Escherichia coli, Streptococcus, Clostridium, Haemophilus, Veillonella, Staphylococcus, and Lactobacillus play an important role in the development of gastric cancer. Besides, lactic acid bacteria (LAB) such as Bifidobacterium, Lactobacillus, Lactococcus, and Streptococcus were found in greater abundance in GAC patients. To identify potential diagnostic and therapeutic interventions for GC, it is essential to understand the mechanistic role of H. pylori and other bacteria that contribute to gastric carcinogenesis. Furthermore, understanding bacteria-host interactions and bacteria-induced inflammatory pathways in the host is critical for developing treatment targets for gastric cancer.
Topics: Humans; Bacterial Proteins; Antigens, Bacterial; Stomach Neoplasms; Microbiota; Helicobacter pylori; Cytotoxins
PubMed: 37530125
DOI: 10.1002/cnr2.1878 -
Translational Psychiatry Dec 2023Schizophrenia (SZ) is a complex psychiatric neurodevelopmental disorder with uncertain etiology and pathogenesis. Increasing evidence has recognized the key role of the...
Schizophrenia (SZ) is a complex psychiatric neurodevelopmental disorder with uncertain etiology and pathogenesis. Increasing evidence has recognized the key role of the gut microbiota in SZ. However, few studies have investigated the potential link between oral microbiota and SZ. We studied the tongue coating microbiota and inflammatory profiles of 118 elderly SZ patients and 97 age-matched healthy controls using Illumina MiSeq sequencing and multiplex immunoassays, respectively. Reduced α-diversity, along with a significant difference in β-diversity, were observed in patients with SZ. We have identified SZ-associated oral dysbiosis, characterized by increased Streptococcus and Fusobacterium, as well as decreased Prevotella and Veillonella. These differential genera could potentially serve as biomarkers for SZ, either alone or in combination. Additionally, an elevated Streptococcus/Prevotella ratio could indicate oral dysbiosis. These differential genera formed two distinct clusters: Streptococcus-dominated and Prevotella-dominated, which exhibited different correlations with the altered immunological profiles. Furthermore, we also observed disruptions in the inferred microbiota functions in SZ-associated microbiota, particularly in lipid and amino acid metabolism. Our study provides novel insights into the characteristics of tongue coating microbiota and its associations with immunological disturbances in elderly SZ patients, which offer new targets for the diagnosis and treatment of SZ in the elderly.
Topics: Humans; Aged; Cross-Sectional Studies; Dysbiosis; Schizophrenia; Microbiota; China
PubMed: 38071192
DOI: 10.1038/s41398-023-02682-1 -
Antibiotics (Basel, Switzerland) May 2023Anaerobic Gram-negative bacteria (AGNB) play a significant role as both pathogens and essential members of the human microbiota. Despite their clinical importance, there...
BACKGROUND
Anaerobic Gram-negative bacteria (AGNB) play a significant role as both pathogens and essential members of the human microbiota. Despite their clinical importance, there remains limited understanding regarding their antimicrobial resistance (AMR) patterns. This knowledge gap poses challenges in effectively managing AGNB-associated infections, as empirical treatment approaches may not adequately address the evolving resistance landscape. To bridge this research gap, we conducted a comprehensive study aimed at exploring the role of human AGNB as a reservoir of AMR. This can provide valuable insights for the prevention and management of anaerobic infections.
METHODS
We studied the prevalence of AMR and AMR determinants conferring resistance to metronidazole (), imipenem (), piperacillin-tazobactam (), cefoxitin (), clindamycin (), chloramphenicol () and mobile genetic elements (MGEs) such as and 1186 associated with the and gene expression. These parameters were studied in spp., spp., spp., spp., spp., and other clinical AGNB.
RESULTS
Resistance to metronidazole, clindamycin, imipenem, piperacillin-tazobactam, cefoxitin and chloramphenicol was 29%, 33.5%, 0.5%, 27.5%, 26.5% and 0%, respectively. The presence of resistance genes, viz., , , , , was detected in 24%, 33.5%, 10%, 9.5%, 21.5% isolates, respectively. None of the tested isolates showed the presence of a gene and MGEs, viz., and IS. The highest resistance to all antimicrobial agents was exhibited by spp. The association between resistant phenotypes and genotypes was complete in clindamycin, as all clindamycin-resistant isolates showed the presence of gene, and none of the susceptible strains harbored this gene; similarly, all isolates were chloramphenicol-susceptible and also lacked the gene, whereas the association was low among imipenem and piperacillin-tazobactam. Metronidazole and imipenem resistance was seen to be dependent on insertion sequences for the expression of AMR genes. A constrained co-existence of and gene in species was seen. Based on the absence and presence of the gene, we divided into two categories, Division I (72.6%) and Division II (27.3%), respectively.
CONCLUSION
AGNB acts as a reservoir of specific AMR genes, which may pose a threat to other anaerobes due to functional compatibility and acquisition of these genes. Thus, AST-complying standard guidelines must be performed periodically to monitor the local and institutional susceptibility trends, and rational therapeutic strategies must be adopted to direct empirical management.
PubMed: 37237845
DOI: 10.3390/antibiotics12050942 -
BMC Microbiology Jul 2020The possibility that smokeless tobacco may contribute to oral carcinogenesis by influencing the oral microbiome has not been explored. This preliminary cross-sectional...
BACKGROUND
The possibility that smokeless tobacco may contribute to oral carcinogenesis by influencing the oral microbiome has not been explored. This preliminary cross-sectional study sought to assess the effect of using shammah, a form of smokeless tobacco prevalent in Arabia, on the tongue microbiome. Tongue scarping samples were obtained from 29 shammah users (SU; 27.34 ± 6.9 years) and 23 shammah non-users (SNU; 27.7 ± 7.19 years) and analyzed with 16S rRNA gene sequencing (V1-V3). Species-level taxonomy assignment of the high-quality, merged reads was obtained using a previously described BLASTn-based algorithm. Downstream analyses were performed with QIIME, LEfSe, and R.
RESULTS
A total of 178 species, belonging to 62 genera and 8 phyla were identified. Genera Streptococcus, Leptotrichia, Actinomyces, Veillonella, Haemophilus, Prevotella and Neisseria accounted for more than 60% of the average microbiome. There were no differences between the two groups in species richness and alpha-diversity, but PCoA showed significant separation (P = 0.015, ANOSIM). LEfSe analysis identified 22 species to be differentially abundant between the SU and SNU. However, only 7 species maintained a false discovery rate of ≤0.2 and could cluster the two groups separately: Rothia mucilaginosa, Streptococcus sp. oral taxon 66, Actinomyces meyeri, Streptococcus vestibularis Streptococcus sanguinis and a potentially novel Veillonella species in association with SU, and Oribacterium asaccharolyticum with SNU.
CONCLUSION
These preliminary results indicate that shammah use induces tongue microbiome changes including enrichment of several species with high acetaldehyde production potential, which warrants further investigation.
Topics: Adult; Bacteria; Case-Control Studies; Cross-Sectional Studies; DNA, Bacterial; DNA, Ribosomal; Humans; Male; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Tobacco, Smokeless; Tongue; Young Adult
PubMed: 32640977
DOI: 10.1186/s12866-020-01883-8 -
Microbiological Research Aug 2022The human oral cavity harbours complex microbial communities with various commensal microorganisms that play pivotal roles in maintaining host health and immunity but...
The human oral cavity harbours complex microbial communities with various commensal microorganisms that play pivotal roles in maintaining host health and immunity but can elicit local and systemic diseases. The role of commensal microorganisms in SARS-CoV-2 infection and disease susceptibility and enrichment of opportunistic pathobionts in the oral cavity is poorly understood. The present study aims to understand the altered landscape of the oral microbiome and mycobiome in SARS-CoV-2 infected patients (n = 30) and its correlation with risk factors compared to non-infected individuals (n = 24) using targeted amplicon sequencing. Diminution of species richness, an elevated abundance of opportunistic pathogens (Veillonella, Acinetobacter, Klebsiella, Prevotella, Gemella, and Streptococcus) and impaired metabolic pathways were observed in the COVID-19 patients. Similarly, altered oral mycobiome with enrichment of known respiratory disease causing pathogenic fungi were observed in the infected individuals. The data further suggested that reduction in immunomodulatory microorganisms lowers the protection of individuals from SARS-CoV-2. Linear discriminant analysis identified several differentially abundant taxa associated with risk factors (ageing and co-morbidities). We also observed distinct bacterial and fungal community structures of elderly infected patients compared to the younger age group members making them highly vulnerable to SARS-CoV-2 infection and disease severity. Furthermore, we also assessed the dynamics of the oral microbiome and mycobiome in symptomatic and asymptomatic patients, host types, co-morbidities, and viral load in the augmentation of specific pathobionts. Overall, the present study demonstrates the microbiome and mycobiome profiling of the COVID-19 infected individuals, the data further suggests that the SARS-CoV-2 infection triggers the prevalence of specific pathobiont.
Topics: Aged; COVID-19; Dysbiosis; Fungi; Humans; Mycobiome; SARS-CoV-2
PubMed: 35597076
DOI: 10.1016/j.micres.2022.127055 -
Frontiers in Microbiology 2020The new coronavirus SARS-CoV-2, the cause of COVID-19, has become a public health emergency of global concern. Like the SARS and influenza pandemics, there have been a... (Review)
Review
The new coronavirus SARS-CoV-2, the cause of COVID-19, has become a public health emergency of global concern. Like the SARS and influenza pandemics, there have been a large number of cases coinfected with other viruses, fungi, and bacteria, some of which originate from the oral cavity. , , and other oral opportunistic pathogens were found in the BALF of the COVID-19 patients by mNGS. Risk factors such as poor oral hygiene, cough, increased inhalation under normal or abnormal conditions, and mechanical ventilation provide a pathway for oral microorganisms to enter the lower respiratory tract and thus cause respiratory disease. Lung hypoxia, typical symptoms of COVID-19, would favor the growth of anaerobes and facultative anaerobes originating from the oral microbiota. SARS-CoV-2 may aggravate lung disease by interacting with the lung or oral microbiota via mechanisms involving changes in cytokines, T cell responses, and the effects of host conditions such as aging and the oral microbiome changes due to systemic diseases. Because the oral microbiome is closely associated with SARS-CoV-2 co-infections in the lungs, effective oral health care measures are necessary to reduce these infections, especially in severe COVID-19 patients. We hope this review will draw attention from both the scientific and clinical communities on the role of the oral microbiome in the current global pandemic.
PubMed: 32849438
DOI: 10.3389/fmicb.2020.01840